Altered Gut Microbiome Composition and Tryptic Activity of the 5xFAD Alzheimer's Mouse Model. - Brandscheid, Carolin; Schuck, Florian; Reinhardt, Sven; Schäfer, Karl-Herbert; Pietrzik, Claus U; Grimm, Marcus; Hartmann, Tobias; Schwiertz, Andreas; Endres, Kristina (J Alzheimers Dis, 2017)
The regulation of physiological gut functions such as peristalsis or secretion of digestive enzymes by the central nervous system via the Nervus vagus is well known. Recent investigations highlight that pathological conditions of neurological or psychiatric disorders might directly interfere with the autonomous neuronal network of the gut - the enteric nervous system, or even derive from there. By using a murine Alzheimer's disease model, we investigated a potential influence of disease-associated changes on gastrointestinal properties. 5xFAD mice at three different ages were compared to wild type littermates in regard to metabolic parameters and enzymes of the gut by fluorimetric enzyme assay and western blotting. Overexpression of human amyloid-β protein precursor (AβPP) within the gut was assessed by qPCR and IHC; fecal microbiome analysis was conducted by 16SrRNA quantitation of selected phyla and species. While general composition of fecal samples, locomotion, and food consumption of male 5xFAD animals were not changed, we observed a reduced body weight occurring at early pathological stages. Human AβPP was not only expressed within the brain of these mice but also in gut tissue. Analysis of fecal proteins revealed a reduced trypsin amount in the 5xFAD model mice as compared to the wild type. In addition, we observed changes in fecal microbiota composition along with age. We therefore suggest that the presence of the mutated transgenes (AβPP and PS1), which are per se the basis for the genetic form of Alzheimer's disease in humans, directly interferes with gut function as shown here for the disease model mice.

Altered Gut Microbiota in a Mouse Model of Alzheimer's Disease. - Zhang, Ling; Wang, Ying; Xiayu, Xia; Shi, Changhua; Chen, Wei; Song, Nan; Fu, Xinjing; Zhou, Rui; Xu, Yan-Feng; Huang, Lan; Zhu, Hua; Han, Yunlin; et al. (J Alzheimers Dis, 2017)
The topic of gut microbiota is currently attracting considerable interest as a potential factor in Alzheimer's disease (AD). However, the extent and time course of alterations in the gut microbiota, and their effects on AD pathology remain uncertain. Herein, we compared the fecal microbiomes and fecal short chain fatty acid composition (SCFAs) between wild-type and AD model mice at different ages under strictly controlled specific pathogen free conditions, and also conducted microscopic investigations of intestinal structures. Our results showed that the microbiota composition and diversity were perturbed and the level of SCFAs was reduced in AD mice, predicting alterations in more than 30 metabolic pathways, which may be associated with amyloid deposition and ultrastructural abnormalities in AD mouse intestine. These findings indicate that AD pathology might not only affect brain function directly, but also exacerbate cognitive deficits through reducing the level of SCFAs via alterations of gut microbiota induced by intestinal amyloid deposition. Our data may support a role of gut microbiota, and suggest a novel route for therapeutic intervention in AD.

Altered Sphingolipid Balance in Capillary Cerebral Amyloid Angiopathy. - de Wit, Nienke M; Snkhchyan, Hripsime; den Hoedt, Sandra; Wattimena, Darcos; de Vos, Rob; Mulder, Monique T; Walter, Jochen; Martinez-Martinez, Pilar; Hoozemans, Jeroen J; Rozemuller, Annemieke J; De Vries, Helga E (J Alzheimers Dis, 2017)
BACKGROUND: The majority of patients with Alzheimer's disease (AD) exhibit amyloid-β (Aβ) deposits at the brain vasculature, a process referred to as cerebral amyloid angiopathy (CAA). In over 51% of AD cases, Aβ also accumulates in cortical capillaries, which is termed capillary CAA (capCAA). It has been postulated that the presence of capCAA in AD is a specific subtype of AD, although underlying mechanisms are not yet fully understood. Sphingolipids (SLs) are implicated in neurodegenerative disorders, including AD. However, to date it remains unknown whether alterations in the SL pathway are involved in capCAA pathogenesis and if these differ from AD. OBJECTIVE: To determine whether AD cases with capCAA have an altered SL profile compared to AD cases without capCAA. METHODS: Immunohistochemistry was performed to assess the expression and localization of ceramide, acid sphingomyelinase (ASM), and sphingosine-1-phosphate receptors (S1P1, S1P3). In addition, we determined the concentrations of S1P as well as different chain-lengths of ceramides using HPLC-MS/MS. RESULTS: Immunohistochemical analysis revealed an altered expression of ceramide, ASM, and S1P receptors by reactive astrocytes and microglial cells specifically associated with capCAA. Moreover, a shift in the balance of ceramides with different chain-lengths and S1P content is observed in capCAA. CONCLUSION: Here we provide evidence of a deregulated SL balance in capCAA. The increased levels of ASM and ceramide in activated glia cells suggest that the SL pathway is involved in the neuroinflammatory response in capCAA pathogenesis. Future research is needed to elucidate the role of S1P in capCAA.

Alzheimer's Disease Biomarkers and Future Decline in Cognitive Normal Older Adults. - Dumurgier, Julien; Hanseeuw, Bernard J; Hatling, Frances B; Judge, Kelly A; Schultz, Aaron P; Chhatwal, Jasmeer P; Blacker, Deborah; Sperling, Reisa A; Johnson, Keith A; Hyman, Bradley T; Gómez-Isla, Teresa (J Alzheimers Dis, 2017)
BACKGROUND: Identifying older adults at risk of cognitive decline represents a challenge as Alzheimer's disease (AD) modifying therapies move toward preclinical stages. OBJECTIVE: To investigate the relationship between AD biomarkers and subsequent change in cognition in a cohort of cognitively intact older adults. METHODS: 84 cognitively normal subjects (mean age 72.0 years, 59% women) were recruited through the Massachusetts Alzheimer's Disease Research Center and the Harvard Aging Brain Study and followed over 3 years. Measurements of amyloid-β 1-42 (Aβ42), total Tau (t-Tau), and Tau phosphorylated at threonine 181 (p-Tau181) in the cerebrospinal fluid (CSF) at study entry were available in all cases. Baseline brain MRI, FDG-PET, and PiB-PET data were available in the majority of participants. Relationship between baseline AD biomarkers and longitudinal change in cognition was assessed using Cox proportional hazard regression and linear mixed models. RESULTS: 14% participants increased their global Clinical Dementia Rating (CDR) score from 0 to 0.5 during follow-up. A CDR score increase was associated with higher baseline CSF t-Tau and p-Tau181, higher global cortical PiB retention, and lower hippocampal volume. The combination of high CSF t-Tau and low Aβ42 or low hippocampal volume was more strongly related to cognitive outcome than each single biomarker. Higher CSF t-Tau was the only biomarker associated with subsequent decline in MMSE score. CONCLUSIONS: Baseline CSF t-Tau and p-Tau181, in vivo amyloid load, and hippocampal volume were all independently associated with future decline in cognition. The discriminatory ability of these biomarkers to predict risk of cognitive decline, however, was only modest.

Alzheimer's Disease: Characterization of the Brain Sites of the Initial Tau Cytoskeletal Pathology Will Improve the Success of Novel Immunological Anti-Tau Treatment Approaches. - Rüb, Udo; Stratmann, Katharina; Heinsen, Helmut; Seidel, Kay; Bouzrou, Mohamed; Korf, Horst-Werner (J Alzheimers Dis, 2017)
Alzheimer's disease (AD) represents the most frequent neurodegenerative disease of the human brain worldwide. Currently practiced treatment strategies for AD only include some less effective symptomatic therapeutic interventions, which unable to counteract the disease course of AD. New therapeutic attempts aimed to prevent, reduce, or remove the extracellular depositions of the amyloid-β protein did not elicit beneficial effects on cognitive deficits or functional decline of AD. In view of the failure of these amyloid-β-based therapeutic trials and the close correlation between the brain pathology of the cytoskeletal tau protein and clinical AD symptoms, therapeutic attention has since shifted to the tau cytoskeletal protein as a novel drug target. The abnormal hyperphosphorylation and intraneuronal aggregation of this protein are early events in the evolution of the AD-related neurofibrillary pathology, and the brain spread of the AD-related tau aggregation pathology may possibly follow a corruptive protein templating and seeding-like mechanism according to the prion hypothesis. Accordingly, immunotherapeutic targeting of the tau aggregation pathology during the very early pre-tangle phase is currently considered to represent an effective and promising therapeutic approach for AD. Recent studies have shown that the initial immunoreactive tau aggregation pathology already prevails in several subcortical regions in the absence of any cytoskeletal changes in the cerebral cortex. Thus, it may be hypothesized that the subcortical brain regions represent the "port of entry" for the pathogenetic agent from which the disease ascends anterogradely as an "interconnectivity pathology".
Keywords: Alzheimer Disease; Amyloid beta-Peptides; Animals; Brain; Humans; Immunotherapy; tau Proteins

Alzheimer's Disease Diagnosis Relies on a Twofold Clinical-Biological Algorithm: Three Memory Clinic Case Reports. - Levy Nogueira, Marcel; Samri, Dalila; Epelbaum, Stéphane; Lista, Simone; Suppa, Per; Spies, Lothar; Hampel, Harald; Dubois, Bruno; Teichmann, Marc (J Alzheimers Dis, 2017)
The International Working Group recently provided revised criteria of Alzheimer's disease (AD) proposing that the diagnosis of typical amnesic AD should be established by a clinical-biological signature, defined by the phenotype of an "amnesic syndrome of the hippocampal type" (ASHT) combined with positive in vivo evidence of AD pathophysiology in the cerebrospinal fluid (CSF) or on amyloid PET imaging. The application and clinical value of this refined diagnostic algorithm, initially intended for research purposes, is explored in three memory clinic cases presenting with different cognitive profiles including an ASHT, hippocampal atrophy, and CSF AD-biomarker data. The case reports highlight that the isolated occurrence of one of the two proposed AD criteria, ASHT or positive pathophysiological markers, does not provide a reliable diagnosis of typical AD. It is proposed that the twofold diagnostic IWG algorithm can be applied and operationalized in memory clinic settings to improve the diagnostic accuracy of typical amnesic AD in clinical practice.

Alzheimer's Disease Genetics and ABCA7 Splicing. - Vasquez, Jared B; Simpson, James F; Harpole, Ryan; Estus, Steven (J Alzheimers Dis, 2017)
Both common and rare polymorphisms within ABCA7 have been associated with Alzheimer's disease (AD). In particular, the rare AD associated polymorphism rs200538373 was associated with altered ABCA7 exon 41 splicing and an AD risk odds ratio of ∼1.9. To probe the role of this polymorphism in ABCA7 splicing, we used minigene studies and qPCR of human brain RNA. We report aberrant ABCA7 exon 41 splicing in the brain of a carrier of the rs200538373 minor C allele. Moreover, minigene studies show that rs200538373 acts as a robust functional variant in vitro. Lastly, although the ABCA7 isoform with an extended exon 41 is predicted to undergo nonsense mediated RNA decay, this was not supported by qPCR analyses, which showed relatively normal ABCA7 mRNA levels in the carrier of the rs200538373 minor C allele. In summary, rs200538373 is a functional polymorphism that alters ABCA7 exon 41 splicing without grossly altering the level of ABCA7 mRNA.

Alzheimer's Disease-Related Polymorphisms in Shunt-Responsive Idiopathic Normal Pressure Hydrocephalus. - Huovinen, Joel; Helisalmi, Seppo; Paananen, Jussi; Laiterä, Tiina; Kojoukhova, Maria; Sutela, Anna; Vanninen, Ritva; Laitinen, Marjo; Rauramaa, Tuomas; Koivisto, Anne M; Remes, Anne M; Soininen, Hilkka; et al. (J Alzheimers Dis, 2017)
BACKGROUND: Idiopathic normal pressure hydrocephalus (iNPH) is a late onset, surgically treated progressive brain disease caused by impaired cerebrospinal fluid dynamics and subsequent ventriculomegaly. Comorbid Alzheimer's disease (AD) seems to be frequent in iNPH. OBJECTIVE: We aim to evaluate the role of AD-related polymorphisms in iNPH. METHODS: Overall 188 shunt-operated iNPH patients and 688 controls without diagnosed neurodegenerative disease were included into analysis. Twenty-three single-nucleotide polymorphisms (SNPs FRMD4A [rs7081208_A, rs2446581_A, rs17314229_T], CR1, BIN, CD2AP, CLU, MS4A6A, MS4A4E, PICALM, ABCA7, CD33, INPP5D, HLA_DRB5, EPHA1, PTK2B, CELF1, SORL1, FERMT2, SLC24A, DSG2, CASS4, and NME8) adjusted to APOE were analyzed between groups by using binary logistic regression analysis. Neuroradiological characteristics and AD-related changes in the right frontal cortical brain biopsies were available for further analysis. RESULTS: Logistic regression analysis adjusted to age, gender, and other SNPs indicated allelic variation of NME8 between iNPH patients and non-demented controls (p = 0.014). The allelic variation of NME8 was not related to the neuropathological changes in the brain biopsies of iNPH patients. However, periventricular white matter changes (p = 0.017) were more frequent in the iNPH patients with the AA-genotype, an identified risk factor of AD. CONCLUSIONS: Our findings increase the evidence that iNPH is characterized by genetic and pathophysiological mechanisms independent from AD. Considering that NME8 plays a role in the ciliary function and displays SNP-related diversity in white matter changes, the mechanisms of NME8 in iNPH and other neurodegenerative processes are worth further study.

Amyloid-Related Imaging Abnormalities in an Aged Squirrel Monkey with Cerebral Amyloid Angiopathy. - Heuer, Eric; Jacobs, Jessica; Du, Rebecca; Wang, Silun; Keifer, Orion P; Cintron, Amarallys F; Dooyema, Jeromy; Meng, Yuguang; Zhang, Xiaodong; Walker, Lary C (J Alzheimers Dis, 2017)
Amyloid-related imaging abnormalities (ARIA) in magnetic resonance imaging scans have emerged as indicators of potentially serious side effects in clinical trials of therapeutics for Alzheimer's disease. These anomalies include an edematous type (ARIA-E) that appears as hyperintense (bright) regions by T2-weighted MRI, and a type characterized by the deposition of hemosiderin (ARIA-H) that elicits a hypointense signal, especially in T2* susceptibility weighted images. ARIA in general has been linked to the presence of amyloid-β (Aβ)-type cerebral amyloid angiopathy, an accumulation of misfolded Aβ protein in the vascular wall that impairs the integrity of brain blood vessels. However, the pathobiology of ARIA remains poorly understood, in part due to the absence of an animal model of the disorder that would enable a contemporaneous analysis of tissue integrity in the affected region. Here we describe both ARIA-E and ARIA-H in an aged squirrel monkey (Saimiri sciureus), a nonhuman primate model of naturally occurring cerebral amyloid angiopathy. Histopathologic examination of the anomalous region revealed reactive astrocytosis and microgliosis, infiltration of systemic inflammatory/immune cells, damage to axons and myelin, and hemosiderin deposition. The disruption of axons in particular suggests that ARIA-E could have functional consequences for affected regions. The squirrel monkey model can be useful for studying the pathogenesis and long-term effects of ARIA, and for testing the safety and efficacy of emerging therapies for Alzheimer's disease.

Amyloid-β Deposition and Long-Term Progression in Mild Cognitive Impairment due to Alzheimer's Disease Defined with Amyloid PET Imaging. - Hatashita, Shizuo; Wakebe, Daichi (J Alzheimers Dis, 2017)
The aim was to evaluate brain amyloid-β (Aβ) deposition in patients with mild cognitive impairment (MCI) due to Alzheimer's disease (AD) using amyloid PET imaging and clarify the relationship between the annual change in Aβ deposition and disease progression. Forty-eight MCI patients underwent neuropsychological assessment and amyloid PET imaging using [11C]-PIB over a follow-up of 5.7±1.5 years. Thirty-nine MCI patients who had an amyloid-positive scan were defined as MCI due to AD, and 9 MCI patients who had an amyloid-negative scan were included. Regions of interest were defined on co-registered MRI, and the PIB standardized uptake value ratio (SUVR) on the same regions was used over follow-up. Annual change in PIB SUVR was calculated. Patients with MCI due to AD had higher baseline PIB SUVR (1.81±0.32, n = 39, p < 0.01) and a greater annual rate of change in PIB SUVR (0.044±0.027, n = 39, p < 0.01) compared to amyloid-negative MCI patients. Twenty-eight (71.8%) progressed to AD. In patients who progressed during a short duration of 1.7±0.8 years, the annual rate of increase in PIB SUVR was 0.101±0.094 (n = 16, p < 0.05), which was greater compared to patients with long conversion or stable patients. There was a negative correlation between the annual rate of increase in PIB SUVR and duration of progression to AD among individual MCI converters (r = -0.47, n = 28, p < 0.05). The patients defined as MCI due to AD could progress to AD with a shorter period if they have a greater increased annual rate in brain Aβ deposition.
Keywords: Aged; Aged, 80 and over; Alzheimer Disease; Amyloid; Aniline Compounds; Cognitive Dysfunction; Disease Progression; Female; Follow-Up Studies; Humans; Image Processing, Computer-Assisted; Magnetic Resonance Imaging; Male; Mental Status Schedule; Middle Aged; Positron-Emission Tomography; Thiazoles

Analytical Strategy to Prioritize Alzheimer's Disease Candidate Genes in Gene Regulatory Networks Using Public Expression Data. - Kawalia, Shweta Bagewadi; Raschka, Tamara; Naz, Mufassra; de Matos Simoes, Ricardo; Senger, Philipp; Hofmann-Apitius, Martin (J Alzheimers Dis, 2017)
Alzheimer's disease (AD) progressively destroys cognitive abilities in the aging population with tremendous effects on memory. Despite recent progress in understanding the underlying mechanisms, high drug attrition rates have put a question mark behind our knowledge about its etiology. Re-evaluation of past studies could help us to elucidate molecular-level details of this disease. Several methods to infer such networks exist, but most of them do not elaborate on context specificity and completeness of the generated networks, missing out on lesser-known candidates. In this study, we present a novel strategy that corroborates common mechanistic patterns across large scale AD gene expression studies and further prioritizes potential biomarker candidates. To infer gene regulatory networks (GRNs), we applied an optimized version of the BC3Net algorithm, named BC3Net10, capable of deriving robust and coherent patterns. In principle, this approach initially leverages the power of literature knowledge to extract AD specific genes for generating viable networks. Our findings suggest that AD GRNs show significant enrichment for key signaling mechanisms involved in neurotransmission. Among the prioritized genes, well-known AD genes were prominent in synaptic transmission, implicated in cognitive deficits. Moreover, less intensive studied AD candidates (STX2, HLA-F, HLA-C, RAB11FIP4, ARAP3, AP2A2, ATP2B4, ITPR2, and ATP2A3) are also involved in neurotransmission, providing new insights into the underlying mechanism. To our knowledge, this is the first study to generate knowledge-instructed GRNs that demonstrates an effective way of combining literature-based knowledge and data-driven analysis to identify lesser known candidates embedded in stable and robust functional patterns across disparate datasets.

Angiotensin-III is Increased in Alzheimer's Disease in Association with Amyloid-β and Tau Pathology. - Kehoe, Patrick Gavin; Hibbs, Elliott; Palmer, Laura E; Miners, J Scott (J Alzheimers Dis, 2017)
Hyperactivity of the renin-angiotensin system (RAS) is associated with the pathogenesis of Alzheimer's disease (AD) believed to be mediated by angiotensin-II (Ang-II) activation of the angiotensin type 1 receptor (AT1R). We previously showed that angiotensin-converting enzyme-1 (ACE-1) activity, the rate-limiting enzyme in the production of Ang-II, is increased in human postmortem brain tissue in AD. Angiotensin-III (Ang-III) activates the AT1R and angiotensin type-2 receptor (AT2R), but its potential role in the pathophysiology of AD remains unexplored. We measured Ang-II and Ang-III levels by ELISA, and the levels and activities of aminopeptidase-A (AP-A) and aminopeptidase-N (AP-N) (responsible for the production and metabolism of Ang-III, respectively) in human postmortem brain tissue in the mid-frontal cortex (Brodmann area 9) in a cohort of AD (n = 90) and age-matched non-demented controls (n = 59), for which we had previous measurements of ACE-1 activity, Aβ level, and tau pathology (also in the mid-frontal cortex). We found that both Ang-II and Ang-III levels were significantly higher in AD compared to age-matched controls and that Ang-III, rather than Ang-II, was strongly associated with Aβ load and tau load. Levels of AP-A were significantly reduced in AD but AP-A enzyme activity was unchanged whereas AP-N activity was reduced in AD but AP-N protein level was unchanged. Together, these data indicate that the APA/Ang-III/APN/Ang-IV/AT4R pathway is dysregulated and that elevated Ang-III could contribute to the pathogenesis of AD.

The Anti-Amyloid-β and Neuroprotective Properties of a Novel Tricyclic Pyrone Molecule. - Maezawa, Izumi; Zou, Bende; Di Lucente, Jacopo; Cao, William S; Pascual, Conrado; Weerasekara, Sahani; Zhang, Man; Xie, Xinmin Simon; Hua, Duy H; Jin, Lee-Way (J Alzheimers Dis, 2017)
There is an urgent unmet need for new therapeutics for Alzheimer's disease (AD), the most common cause of dementia in the elderly. Therapeutic approaches targeting amyloid-β (Aβ) and its downstream toxicities have become major strategies in AD drug development. We have taken a rational design approach and synthesized a class of tricyclic pyrone (TP) compounds that show anti-Aβ and other neuroprotective actions. The in vivo efficacy of a lead TP named CP2 to ameliorate AD-like pathologies has been shown in mouse models. Here we report the selection and initial characterization of a new lead TP70, which exhibited an anti-Aβ therapeutic index even higher than CP2. Moreover, TP70 was able to reduce oxidative stress, inhibit acyl-coenzyme A:cholesterol acyltransferase (ACAT), and upregulate the expression of ATP-binding cassette subfamily A, member 1 (ABCA1), actions considered neuroprotective in AD. TP70 further showed excellent pharmacokinetic properties, including brain penetration and oral availability. When administered to 5xFAD mice via intraperitoneal or oral route, TP70 enhanced the overall solubility and decreased the level of cerebral Aβ, including both fibrillary and soluble Aβ species. Interestingly, TP70 enhanced N-methyl-D-aspartate (NMDA) receptor-mediated excitatory post-synaptic potential (EPSP) in the hippocampal CA1 area, increased the magnitude of NMDA-dependent hippocampal long-term potentiation (LTP), a cellular model of learning and memory, and prevented the Aβ oligomer-impaired LTP. Significantly, a single dose of TP70 administered to aged 5xFAD mice was effective in mitigating the impaired LTP induction, recorded at 24 h after administration. Our results support a potential of TP70 in clinical development for AD in view of its synergistic neuroprotective actions, ability to positively modulate NMDA receptor-mediated hippocampal plasticity, and favorable pharmacokinetic properties in rodents.

Antibodies to Signaling Molecules and Receptors in Alzheimer's Disease are Associated with Psychomotor Slowing, Depression, and Poor Visuospatial Function. - Giil, Lasse M; Vedeler, Christian A; Kristoffersen, Einar K; Nordrehaug, Jan Erik; Heidecke, Harald; Dechend, Ralf; Schulze-Forster, Kai; Muller, Dominik N; von Goetze, Victoria S; Cabral-Marques, Otavio; Riemekasten, Gabriela; Vogelsang, Petra; et al. (J Alzheimers Dis, 2017)
BACKGROUND: Alzheimer's disease (AD) is associated with several antibodies as well as signaling molecules and receptors. These may be detrimental in the presence of a disrupted blood-brain barrier (BBB). OBJECTIVE: To investigate whether the levels of antibodies toward 33 signaling molecules involved in neurotransmitter, vascular, and immune functions were associated with AD and, within the AD group; cognitive function and mood. METHODS: Antibodies in sera from patients with mild AD [(n = 91) defined as a Mini-Mental State Examination ≥ 20 or a Clinical Dementia Rating Scale≤1] and healthy controls (n = 102) were measured with enzyme-linked immunosorbent assays. Levels in AD and controls were compared by Mann-Whitney test. In the AD group, associations between antibodies and psychometric test scores were analyzed by robust regression. The false discovery threshold was set to 0.05. RESULTS: Antibodies to serotonin receptors [5-HT2AR (effect size (r) = 0.21, p = 0.004), 5-HT2CR (r = 0.25, p = 0.0005) and 5-HT7R (r = 0.21, p = 0.003)], vascular endothelial growth factor receptor 1 [VEGFR1 (r = 0.29, p < 0.001)] and immune-receptors (Stabilin-1 (r = 0.23, p = 0.001) and C5aR1 (r = 0.21, p = 0.004) were higher in AD. Psychomotor speed was associated with D1R-abs (β 0.49, p < 0.001), depression with ETAR-abs (β 0.31, p < 0.001), and visuospatial function with 5-HT1AR-abs (β 0.27, p = 0.004) despite similar antibody levels compared to controls. CONCLUSIONS: Antibody levels to VEGFR1, serotonergic receptors, and receptors in the immune system were increased in AD. Antibodies at similar levels as in controls were associated cognitive dysfunction and depression in AD.

Anticholinergic Exposure and Risk of Pneumonia in Persons with Alzheimer's Disease: A Nested Case-Control Study. - Lampela, Pasi; Tolppanen, Anna-Maija; Tanskanen, Antti; Tiihonen, Jari; Hartikainen, Sirpa; Taipale, Heidi (J Alzheimers Dis, 2017)
BACKGROUND: Risk of pneumonia is increased in persons with Alzheimer's disease (AD). In some studies, anticholinergic drugs (AC) have been associated with an increased pneumonia risk. OBJECTIVE: We analyzed the risk of pneumonia associated with ACs in persons with AD. METHODS: We performed a nested case-control study using register-based data from a Finnish nationwide MEDALZ cohort including all community-dwelling persons diagnosed with AD during 2005-2011. Cases were identified based on pneumonia diagnoses (n = 12,442) from hospital discharge and causes of death registers. Up to two controls without pneumonia were matched based on time since AD diagnoses, age, and gender for each case; AC use was measured using Anticholinergic Drug Scale. RESULTS: Use of AC was associated with an increased risk of pneumonia (adjusted odds ratio (OR) 1.36, 95% confidence interval (CI) 1.29-1.43). However, there was no increased pneumonia risk in persons using level 3 ACs. Incident use was associated with higher risk of pneumonia (OR 2.68, 95% CI 2.15-3.34) than prevalent use (OR 1.48, 95% CI 1.40-1.57). Among persons using cholinesterase inhibitors (AChEIs), risk of pneumonia was increased in persons using also ACs (OR 1.53, 95% CI 1.41-1.66). CONCLUSION: ACs were associated with an increased risk of pneumonia in persons with AD, especially at the time of initiation of these drugs. AC use was associated with increased pneumonia risk also in persons using AChEIs. This risk should be carefully considered when treating AD patients.

Aortic Valve Calcification and the Risk of dementia: A Population-Based Study. - Wolters, Frank J; Bos, Daniel; Vernooij, Meike W; Franco, Oscar H; Hofman, Albert; Koudstaal, Peter J; van der Lugt, Aad; Ikram, M Arfan (J Alzheimers Dis, 2017)
The association of aortic valve calcification (AVC) with dementia remains unknown. In 2,428 non-demented participants from the population-based Rotterdam Study, we investigated the association of CT-assessed AVC with risk of dementia and cognitive decline. AVC was present in 33.1% of the population. During a median follow-up of 9.3 years, 160 participants developed dementia. We found no association between presence of AVC and risk of all-cause dementia [hazard ratio (HR): 0.89 (95% confidence interval (CI):0.63;1.26)]. Presence of AVC was not associated with cognitive decline on any of the cognitive tests, nor with a measure of global cognition.

APOEɛ4 Genotype, Amyloid, and Clinical Disease Progression in Cognitively Normal Older Adults. - Hollands, Simone; Lim, Yen Ying; Laws, Simon M; Villemagne, Victor L; Pietrzak, Robert H; Harrington, Karra; Porter, Tenielle; Snyder, Peter; Ames, David; Fowler, Christopher; Rainey-Smith, Stephanie R; Martins, Ralph N; et al. (J Alzheimers Dis, 2017)
BACKGROUND: In cognitively normal (CN) older adults, carriage of the apolipoprotein E (APOE) ɛ4 allele is associated with increased risk for dementia of the Alzheimer type (AD-dementia). It is unclear whether this occurs solely through APOEɛ4 increasing amyloid-β (Aβ) accumulation or through processes independent of Aβ. OBJECTIVE: To determine the extent and nature to which APOEɛ4 increases risk for clinical disease progression in CN older adults. METHODS: Data from the total (n = 765) and Aβ-imaged (n = 423) CN cohort in the Australian Imaging, Biomarker and Lifestyle (AIBL) Study of Ageing was analyzed using Cox proportional hazard models to estimate ɛ4 risk for clinical disease progression over a 72-month follow-up. RESULTS: With Aβ status unknown and risk from demographic characteristics controlled, ɛ4 carriage increased risk for clinical disease progression over 72 months by 2.66 times compared to risk of non-ɛ4 carriage. Re-analysis with Aβ status included showed that abnormally high Aβ increased risk for clinical disease progression over 72 months by 2.11 times compared to risk of low Aβ. However, with Aβ level known, ɛ4 carriage was no longer predictive of clinical disease progression. CONCLUSION: In CN older adults, the risk of ɛ4 for clinical disease progression occurs through the effect of ɛ4 increasing Aβ levels.

APP Mutations in Cerebral Amyloid Angiopathy with or without Cortical Calcifications: Report of Three Families and a Literature Review. - Sellal, François; Wallon, David; Martinez-Almoyna, Laurent; Marelli, Cecilia; Dhar, Abhinav; Oesterlé, Héléne; Rovelet-Lecrux, Anne; Rousseau, Stéphane; Kourkoulis, Christina E; Rosand, Jon; DiPucchio, Zora Y; Frosch, Matthew; et al. (J Alzheimers Dis, 2017)
BACKGROUND: Specific APP mutations cause cerebral amyloid angiopathy (CAA) with or without Alzheimer's disease (AD). OBJECTIVE: We aimed at reporting APP mutations associated with CAA, describe the clinical, cerebrospinal fluid AD biomarkers, and neuroimaging features, and compare them with the data from the literature. METHODS: We performed a retrospective study in two French genetics laboratories by gathering all clinical and neuroimaging data from patients referred for a genetic diagnosis of CAA with an age of onset before 66 years and fulfilling the other Boston revised criteria. We studied the segregation of mutations in families and performed a comprehensive literature review of all cases reported with the same APP mutation. RESULTS: We screened APP in 61 unrelated French patients. Three mutations, located in the Aβ coding region, were detected in five patients from three families: p.Ala692Gly (Flemish), p.Glu693Lys (Italian), and p.Asp694Asn (Iowa). Patients exhibited CAA and progressive cognitive impairment associated with cortical calcifications in the Iowa and Italian mutation carriers, but not the patient carrying the Flemish mutation. CONCLUSIONS: This is the first evidence of cortical calcification in patients with an APP mutation other than the Iowa mutation. We discuss the radiological, cerebrospinal fluid, and clinical phenotype of patients carrying these mutations in the literature.

Association Between Later Life Lifestyle Factors and Alzheimer's Disease Biomarkers in Non-Demented Individuals: A Longitudinal Descriptive Cohort Study. - Reijs, Babette L R; Vos, Stephanie J B; Soininen, Hilkka; Lötjönen, Jyrki; Koikkalainen, Juha; Pikkarainen, Maria; Hall, Anette; Vanninen, Ritva; Liu, Yawu; Herukka, Sanna-Kaisa; Freund-Levi, Yvonne; Frisoni, Giovanni B; et al. (J Alzheimers Dis, 2017)
BACKGROUND: Lifestyle factors have been associated with the risk of dementia, but the association with Alzheimer's disease (AD) remains unclear. OBJECTIVE: To examine the association between later life lifestyle factors and AD biomarkers (i.e., amyloid-β 1-42 (Aβ42) and tau in cerebrospinal fluid (CSF), and hippocampal volume) in individuals with subjective cognitive decline (SCD) and mild cognitive impairment (MCI). In addition, to examine the effect of later life lifestyle factors on developing AD-type dementia in individuals with MCI. METHODS: We selected individuals with SCD (n = 111) and MCI (n = 353) from the DESCRIPA and Kuopio Longitudinal MCI studies. CSF Aβ42 and tau concentrations were assessed with ELISA assay and hippocampal volume with multi-atlas segmentation. Lifestyle was assessed by clinical interview at baseline for: social activity, physical activity, cognitive activity, smoking, alcohol consumption, and sleep. We performed logistic and Cox regression analyses adjusted for study site, age, gender, education, and diagnosis. Prediction for AD-type dementia was performed in individuals with MCI only. RESULTS: Later life lifestyle factors were not associated with AD biomarkers or with conversion to AD-type dementia. AD biomarkers were strongly associated with conversion to AD-type dementia, but these relations were not modulated by lifestyle factors. Apolipoprotein E (APOE) genotype did not influence the results. CONCLUSIONS: Later life lifestyle factors had no impact on key AD biomarkers in individuals with SCD and MCI or on conversion to AD-type dementia in MCI.

The Association between Montreal Cognitive Assessment Memory Scores and Hippocampal Volume in a Neurodegenerative Disease Sample. - Ritter, Aaron; Hawley, Nanako; Banks, Sarah J; Miller, Justin B (J Alzheimers Dis, 2017)
Despite widespread use, there have been few investigations into the neuroanatomical correlates of the Montreal Cognitive Assessment (MoCA). In a sample of 138 consecutive patients presenting with cognitive complaints, we report significant correlations between lower MoCA memory scores and smaller hippocampal volumes (r = 0.36-0.41, p < 0.001). We also report that the newly devised memory index score, designed to better capture encoding deficits than the standard delayed recall score, was not significantly better for predicting hippocampal volume. These initial results suggest that poor performance on the MoCA's memory section should prompt further evaluation for hippocampal atrophy.

Association of Central Arterial Stiffness and Pressure Pulsatility with Mild Cognitive Impairment and Dementia: The Atherosclerosis Risk in Communities Study-Neurocognitive Study (ARIC-NCS). - Meyer, Michelle L; Palta, Priya; Tanaka, Hirofumi; Deal, Jennifer A; Wright, Jacqueline; Knopman, David S; Griswold, Michael E; Mosley, Thomas H; Heiss, Gerardo (J Alzheimers Dis, 2017)
BACKGROUND: The association of central arterial stiffness and pressure pulsatility with mild cognitive impairment (MCI) and dementia is not well characterized in the population-based setting. OBJECTIVE: The aim of this study was to quantify the cross-sectional association of arterial stiffness and pressure pulsatility with MCI and dementia among 4,461 older white and black adults from the population-based Atherosclerosis Risk in Communities Study-Neurocognitive Study. METHODS: We used race-stratified multinomial logistic regression to evaluate associations of percentile cut points of carotid-femoral pulse wave velocity, central systolic blood pressure, central pulse pressure, and pulse pressure amplification with MCI and dementia versus no cognitive impairment. RESULTS: Among whites, those with carotid-femoral pulse wave velocity or central systolic blood pressure ≥75th percentile had a higher prevalence of MCI compared to participants <75th percentile (conditional odds ratio (OR); 95% confidence interval (CI): 1.27 (1.02, 1.56) and 1.28 (1.04, 1.57), respectively) and those with central pulse pressure ≥75th percentile had a higher prevalence of MCI (OR 1.27 (95% CI: 1.03, 1.58)) and dementia (OR 1.76 (95% CI: 1.06, 2.92) compared to participants <75th percentile. Also among whites, those with pulse pressure amplification ≤25th percentile had a higher prevalence of dementia compared to participants >25th percentile (OR 1.65; (95% CI: 1.01, 2.70). Weaker associations were seen among black participants. CONCLUSION: Higher arterial stiffness and pulsatility were associated with MCI and dementia in white participants. Longitudinal characterization of the observed associations is warranted to assess whether arterial stiffness and pressure pulsatility predict MCI and dementia among older adults.

Associations of CAIDE Dementia Risk Score with MRI, PIB-PET measures, and cognition. - Stephen, Ruth; Liu, Yawu; Ngandu, Tiia; Rinne, Juha O; Kemppainen, Nina; Parkkola, Riitta; Laatikainen, Tiina; Paajanen, Teemu; Hänninen, Tuomo; Strandberg, Timo; Antikainen, Riitta; Tuomilehto, Jaakko; et al. (J Alzheimers Dis, 2017)
BACKGROUND: CAIDE Dementia Risk Score is the first validated tool for estimating dementia risk based on a midlife risk profile. OBJECTIVES: This observational study investigated longitudinal associations of CAIDE Dementia Risk Score with brain MRI, amyloid burden evaluated with PIB-PET, and detailed cognition measures. METHODS: FINGER participants were at-risk elderly without dementia. CAIDE Risk Score was calculated using data from previous national surveys (mean age 52.4 years). In connection to baseline FINGER visit (on average 17.6 years later, mean age 70.1 years), 132 participants underwent MRI scans, and 48 underwent PIB-PET scans. All 1,260 participants were cognitively assessed (Neuropsychological Test Battery, NTB). Neuroimaging assessments included brain cortical thickness and volumes (Freesurfer 5.0.3), visually rated medial temporal atrophy (MTA), white matter lesions (WML), and amyloid accumulation. RESULTS: Higher CAIDE Dementia Risk Score was related to more pronounced deep WML (OR 1.22, 95% CI 1.05-1.43), lower total gray matter (β-coefficient -0.29, p = 0.001) and hippocampal volume (β-coefficient -0.28, p = 0.003), lower cortical thickness (β-coefficient -0.19, p = 0.042), and poorer cognition (β-coefficients -0.31 for total NTB score, -0.25 for executive functioning, -0.33 for processing speed, and -0.20 for memory, all p < 0.001). Higher CAIDE Dementia Risk Score including APOE genotype was additionally related to more pronounced MTA (OR 1.15, 95% CI 1.00-1.30). No associations were found with periventricular WML or amyloid accumulation. CONCLUSIONS: The CAIDE Dementia Risk Score was related to indicators of cerebrovascular changes and neurodegeneration on MRI, and cognition. The lack of association with brain amyloid accumulation needs to be verified in studies with larger sample sizes.

Atrial Fibrillation is Independently Associated with Cognitive Impairment after Ischemic Stroke. - Chander, Russell Jude; Lim, Levinia; Handa, Sagarika; Hiu, Shaun; Choong, Angeline; Lin, Xuling; Singh, Rajinder; Oh, Daniel; Kandiah, Nagaendran (J Alzheimers Dis, 2017)
BACKGROUND: While atrial fibrillation (AF) is an important risk factor for ischemic strokes and mild cognitive impairment (MCI) in Alzheimer's disease, the association between AF and post-stroke cognitive impairment (PSCI), and the factors mediating this association, is unclear. OBJECTIVE: To investigate the role of AF in PSCI, especially in relation to other markers of cerebrovascular disease. METHODS: 445 subjects with mild ischemic stroke without pre-stroke cognitive decline were assessed 3-6 months post-stroke for cognitive deficits. MRIs were reviewed by trained raters for acute infarct characteristics, global cortical atrophy, white matter hyperintensities, cerebral microbleeds, and intracranial stenosis. Logistic regression analysis was used to identify factors independently associated with PSCI. Subjects were also categorized according to paroxysmal (pAF) or persistent/chronic AF (p/cAF), and presence or absence of AF or large cortical infarcts (LCI) to study cognitive trends. RESULTS: 80 (18.0%) subjects had AF. 76.3% of AF subjects and 42.7% of subjects without AF had PSCI. The odds ratio (OR) of AF in developing PSCI was 2.31 (95% CI: 1.12-4.75; p = 0.035), after correcting for other risk factors. pAF subjects and AF subjects with LCIs had higher ORs for PSCI. AF subjects performed worse in neuropsychological tasks associated with global cognition, episodic memory, and executive function. CONCLUSION: AF is a significant risk factor for PSCI, even after correcting for AF-related infarcts. Other mechanisms, such as hypoperfusion, microhemorrhages, and neuroinflammation, may be at play. All stroke patients with AF, regardless of the type of infarction, should be closely monitored for PSCI.

Attitudes toward Potential Participant Registries. - Grill, Joshua D; Holbrook, Andrew; Pierce, Aimee; Hoang, Dan; Gillen, Daniel L (J Alzheimers Dis, 2017)
Difficult participant recruitment is a consistent barrier to successful medical research. Potential participant registries represent an increasingly common intervention to overcome this barrier. A variety of models for registries exist, but few data are available to instruct their design and implementation. To provide such data, we surveyed 110 cognitively normal research participants enrolled in a longitudinal study of aging and dementia. Seventy-four (67%) individuals participated in the study. Most (78%, CI: 0.67, 0.87) participants were likely to enroll in a registry. Willingness to participate was reduced for registries that required enrollment through the Internet using a password (26%, CI: 0.16, 0.36) or through email (38%, CI: 0.27, 0.49). Respondents acknowledged their expectations that researchers share information about their health and risk for disease and their concerns that their data could be shared with for-profit companies. We found no difference in respondent preferences for registries that shared contact information with researchers, compared to honest broker models that take extra precautions to protect registrant confidentiality (28% versus 30%; p = 0.46). Compared to those preferring a shared information model, respondents who preferred the honest broker model or who lacked model preference voiced increased concerns about sharing registrant data, especially with for-profit organizations. These results suggest that the design of potential participant registries may impact the population enrolled, and hence the population that will eventually be enrolled in clinical studies. Investigators operating registries may need to offer particular assurances about data security to maximize registry enrollment but also must carefully manage participant expectations.

Autonomic Nervous System Dysfunctions as a Basis for a Predictive Model of Risk of Neurological Disorders in Subjects with Prior History of Traumatic Brain Injury: Implications in Alzheimer's Disease. - Ho, Lap; Legere, Marc; Li, Tongbin; Levine, Samara; Hao, Ke; Valcarcel, Breanna; Pasinetti, Giulio M (J Alzheimers Dis, 2017)
Autonomic dysfunction is very common in patients with dementia, and its presence might also help in differential diagnosis among dementia subtypes. Various central nervous system structures affected in Alzheimer's disease (AD) are also implicated in the central autonomic nervous system (ANS) regulation. For example, deficits in central cholinergic function in AD could likely lead to autonomic dysfunction. We recently developed a simple, readily applicable evaluation for monitoring ANS disturbances in response to traumatic brain injury (TBI). This ability to monitor TBI allows for the possible detection and targeted prevention of long-term, detrimental brain responses caused by TBI that lead to neurodegenerative diseases such as AD. We randomly selected and extracted de-identified medical record information from subjects who have been assessed using the ANS evaluation protocol. Using machine learning strategies in the analysis of information from individual as well as a combination of ANS evaluation protocol components, we identified a novel prediction model that is effective in correctly segregating between cases with or without a documented history of TBI exposure. Results from our study support the hypothesis that trauma-induced ANS dysfunctions may contribute to clinical TBI features. Because autonomic dysfunction is very common in AD patients it is possible that TBI may also contribute to AD and/or other forms of dementia through these novel mechanisms. This study provides a novel prediction model to physiologically assess the likelihood of subjects with prior history of TBI to develop clinical TBI complications, such as AD.

Autophagy-ERK1/2-Involved Disinhibition of Hippocampal Neurons Contributes to the Pre-Synaptic Toxicity Induced by Aβ42 Exposure. - Yin, Yanling; Zhao, Yuanyuan; Han, Song; Zhang, Nan; Chen, Hanyu; Wang, Xiaomin (J Alzheimers Dis, 2017)
Alzheimer's disease (AD) is a progressive neurodegenerative disease and the most frequent cause of progressive cognitive decline in the elderly population. To date, there is still no effective treatment for AD, requiring more underlying mechanisms. In the present study, we investigated the effects of Aβ42 on the inhibitory synaptic transmission in the cultured hippocampal neurons, and explored the possible mechanism. The frequency, but not amplitude, of miniature inhibitory post-synaptic currents was significantly suppressed by Aβ42, indicating that Aβ42 played its role in inhibitory transmitter release at the pre-synaptic sites. Aβ42 had no effect on miniature excitatory post-synaptic currents, suggesting GABAergic synapses are more susceptible to Aβ42 exposure. However, the number of GABAergic neurons or synapses was not influenced, suggesting the corresponding stage may be a preclinical one. The effect of Aβ42 can be mimicked by PD98059 (an inhibitor of ERK1/2) and blocked by curcumin (an activator of MEK), which reveals Aβ-involved influence is via the decreased phosphorylation of MAPK-ERK1/2. In addition, synaptophysin is confirmed to be a downstream protein of MAPK-ERK1/2 at the pre-synaptic site. At the same time, suppressed autophagy was observed after Aβ42 exposure, and the activation of autophagy increased pERK1/2 level and salvaged the disinhibition of hippocampal neurons. These data suggest that diminished GABAergic tone likely starts from the preclinical stage of AD, so some GABAergic stress test may be effective for identifying cognitively normal elder adults. Strategies against the dysfunction of autophagy should be adopted in the early stage of AD because of its initial effects.

AZD3293: Pharmacokinetic and Pharmacodynamic Effects in Healthy Subjects and Patients with Alzheimer's Disease. - Cebers, Gvido; Alexander, Robert C; Haeberlein, Samantha Budd; Han, David; Goldwater, Ronald; Ereshefsky, Larry; Olsson, Tina; Ye, Naidong; Rosen, Laura; Russell, Muir; Maltby, Justine; Eketjäll, Susanna; et al. (J Alzheimers Dis, 2017)
AZD3293 (LY3314814) is a promising new potentially disease-modifying BACE1 (β-secretase) inhibitor in Phase III clinical development for the treatment of Alzheimer's disease. Reported here are the first two Phase I studies: (1) a single ascending dose study evaluating doses of 1-750 mg with a food-effect component (n = 72), and (2) a 2-week multiple ascending dose study evaluating doses of 15 or 50 mg once daily (QD) or 70 mg once weekly (QW) in elderly subjects (Part 1, n = 31), and 15, 50, or 150 mg QD in patients with mild to moderate Alzheimer's disease (Part 2, n = 16). AZD3293 was generally well tolerated up to the highest doses given. No notable food effects were observed. PK following multiple doses (Part 2) were tmax of 1 to 3 h and mean t1/2 of 16 to 21 h across the 15 to 150 mg dose range. For single doses of ≥5 mg, a ≥70% reduction was observed in mean plasma Aβ40 and Aβ42 concentrations, with prolonged suppression for up to 3 weeks at the highest dose level studied. Following multiple doses, robust reductions in plasma (≥64% at 15 mg and ≥78% at ≥50 mg) and cerebrospinal fluid (≥51% at 15 mg and ≥76% at ≥50 mg) Aβ peptides were seen, including prolonged suppression even with a QW dosing regimen. AZD3293 is the only BACE1 inhibitor for which prolonged suppression of plasma Aβ with a QW dosing schedule has been reported. Two Phase III studies of AZD3293 (AMARANTH, NCT02245737; and DAYBREAK-ALZ, NCT02783573) are now ongoing.

Baseline Telomere Length and Effects of a Multidomain Lifestyle Intervention on Cognition: The FINGER Randomized Controlled Trial. - Sindi, Shireen; Ngandu, Tiia; Hovatta, Iiris; Kåreholt, Ingemar; Antikainen, Riitta; Hänninen, Tuomo; Levälahti, Esko; Laatikainen, Tiina; Lindström, Jaana; Paajanen, Teemu; Peltonen, Markku; Khalsa, Dharma Singh; et al. (J Alzheimers Dis, 2017)
Leukocyte telomere length (LTL) is a biomarker of aging, and it is associated with lifestyle. It is currently unknown whether LTL is associated with the response to lifestyle interventions. The goal is to assess whether baseline LTL modified the cognitive benefits of a 2-year multidomain lifestyle intervention (exploratory analyses). The Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability (FINGER) was a 2-year randomized controlled trial including 1,260 people at risk of cognitive decline, aged 60-77 years identified from the general population. Participants were randomly assigned to the lifestyle intervention (diet, exercise, cognitive training, and vascular risk management) and control (general health advice) groups. Primary outcome was change in cognition (comprehensive neuropsychological test battery). Secondary outcomes were changes in cognitive domains: memory, executive functioning, and processing speed. 775 participants (392 control, 383 intervention) had baseline LTL (peripheral blood DNA). Mixed effects regression models with maximum likelihood estimation were used to analyze change in cognition as a function of randomization group, time, baseline LTL, and their interaction. Intervention and control groups did not significantly differ at baseline. Shorter LTL was related to less healthy baseline lifestyle. Intervention benefits on executive functioning were more pronounced among those with shorter baseline LTL (p-value for interaction was 0.010 adjusted for age and sex, and 0.007 additionally adjusted for baseline lifestyle factors). The FINGER intervention cognitive benefits were more pronounced with shorter baseline LTL, particularly for executive functioning, indicating that the multidomain lifestyle intervention was especially beneficial among higher-risk individuals.

BDNF Responses in Healthy Older Persons to 35 Minutes of Physical Exercise, Cognitive Training, and Mindfulness: Associations with Working Memory Function. - Håkansson, Krister; Ledreux, Aurélie; Daffner, Kirk; Terjestam, Yvonne; Bergman, Patrick; Carlsson, Roger; Kivipelto, Miia; Winblad, Bengt; Granholm, Ann-Charlotte; Mohammed, Abdul Kadir H (J Alzheimers Dis, 2017)
Brain-derived neurotrophic factor (BDNF) has a central role in brain plasticity by mediating changes in cortical thickness and synaptic density in response to physical activity and environmental enrichment. Previous studies suggest that physical exercise can augment BDNF levels, both in serum and the brain, but no other study has examined how different types of activities compare with physical exercise in their ability to affect BDNF levels. By using a balanced cross over experimental design, we exposed nineteen healthy older adults to 35-minute sessions of physical exercise, cognitive training, and mindfulness practice, and compared the resulting changes in mature BDNF levels between the three activities. We show that a single bout of physical exercise has significantly larger impact on serum BDNF levels than either cognitive training or mindfulness practice in the same persons. This is the first study on immediate BDNF effects of physical activity in older healthy humans and also the first study to demonstrate an association between serum BDNF responsivity to acute physical exercise and working memory function. We conclude that the BDNF increase we found after physical exercise more probably has a peripheral than a central origin, but that the association between post-intervention BDNF levels and cognitive function could have implications for BDNF responsivity in serum as a potential marker of cognitive health.

Benefits of Occupational Therapy in Dementia Patients: Findings from a Real-World Observational Study. - Pimouguet, Clément; Le Goff, Mélanie; Wittwer, Jérôme; Dartigues, Jean-François; Helmer, Catherine (J Alzheimers Dis, 2017)
BACKGROUND: There is a growing interest in developing non-pharmacological approaches in dementia. Clinical efficacy of occupational therapy (OT) under routine care conditions has not been investigated yet. OBJECTIVE: To analyze the short-term effects of OT in patients with dementia; and to identify factors related to greater benefit. METHODS: Patients referred to OT were evaluated before starting a 3-month intervention and at 3 and 6 months later. Measures included: Mini-Mental State Examination (MMSE), Disability Assessment in Dementia (DAD), Neuropsychiatric Inventory (NPI) Questionnaire, patients' quality of life (EQ 5D-VAS), caregivers' burden (Zarit scale), and amount of informal care. Linear mixed models were used to analyze trajectories of outcomes. Logistic regressions with stepwise descending selection were used to study factors associated with benefits. RESULTS: 421 dementia patients benefited from OT (mean MMSE = 17.3). Patients remained cognitively stable over time. Functional performances also remained stable at 3 months and significantly decreased at 6 months (crude reduction of 2.8 points, p < 0.01). Behavioral troubles were significantly reduced over the intervention period and remained stable after (p < 0.01). Patients' quality of life increased over the 3-month intervention (p = 0.16) and significantly decreased thereafter. Caregivers' burden and informal care significantly decreased over the 3-month intervention and remained stable thereafter. Patients who benefited from OT with regard to function were less educated and had higher cognitive level. CONCLUSION: OT may be an effective intervention to maintain cognition and functionality and to reduce psychiatric symptoms in dementia patients. Mild stages of dementia could gain more benefits from OT with regard to functional decline.

Brain Regions Involved in Arousal and Reward Processing are Associated with Apathy in Alzheimer's Disease and Frontotemporal Dementia. - Huey, Edward D; Lee, Seonjoo; Cheran, Gayathri; Grafman, Jordan; Devanand, Davangere P (J Alzheimers Dis, 2017)
BACKGROUND: Apathy is a common and problematic symptom of several neurodegenerative illnesses, but its neuroanatomical bases are not understood. OBJECTIVE: To determine the regions associated with apathy in subjects with mild Alzheimer's disease (AD) using a method that accounts for the significant co-linearity of regional atrophy and neuropsychiatric symptoms. METHODS: We identified 57 subjects with mild AD (CDR = 1) and neuropsychiatric symptoms in the Alzheimer's Disease Neuroimaging Initiative (ADNI) database. We performed a multivariate multiple regression with LASSO regularization on all symptom subscales of the Neuropsychiatric Inventory and the whole-brain ROI volumes calculated from their baseline MRIs with FreeSurfer. We compared our results to those from a previous study using the same method in patients with frontotemporal dementia (FTD) and corticobasal syndrome (CBS). RESULTS: Of neuropsychiatric symptoms, apathy showed the most robust neuroanatomical associations in the AD subjects. Atrophy of the following regions were independently associated with apathy: the ventromedial prefrontal cortex; ventrolateral prefrontal cortex; posterior cingulate cortex and adjacent lateral cortex; and the bank of the superior temporal sulcus. These results replicate previous studies using FTD and CBS patients, mostly agree with the previous literature on apathy in AD, and correspond to the Medial and Orbital Prefrontal Cortex networks identified in non-human primates. CONCLUSION: The current study, previous studies from our laboratory, and the previous literature suggest that impairment of the same brain networks involved in arousal, threat response, and reward processing are associated with apathy in AD and FTD.

Can Better Management of Periodontal Disease Delay the Onset and Progression of Alzheimer's Disease? - Harding, Alice; Robinson, Sarita; Crean, StJohn; Singhrao, Sim K (J Alzheimers Dis, 2017)
A risk factor relationship exists between periodontal disease and Alzheimer's disease (AD) via tooth loss, and improved memory following dental intervention. This links the microbial contribution from indigenous oral periodontal pathogens to the manifestation of chronic conditions, such as AD. Here, we use Porphyromonas gingivalis infection to illustrate its effect on mental health. P. gingivalis infection, in its primary sub-gingival niche, can cause polymicrobial synergy and dysbiosis. Dysbiosis describes the residency of select commensals from the oral cavity following co-aggregation around the dominant keystone pathogen, such as P. gingivalis, to gain greater virulence. The initial process involves P. gingivalis disturbing neutrophil mediated innate immune responses in the healthy gingivae and then downregulating adaptive immune cell differentiation and development to invade, and subsequently, establish new dysbiotic bacterial communities. Immune responses affect the host in general and functionally via dietary adjustments caused by tooth loss. Studies from animals orally infected with P. gingivalis confirm this bacterium can transmigrate to distant organ sites (the brain) and contribute toward peripheral and intracerebral inflammation, and compromise vascular and microvascular integrity. In another study, P. gingivalis infection caused sleep pattern disturbances by altering glial cell light/dark molecular clock activity, and this, in turn, can affect the clearance of danger associated molecular patterns, such as amyloid-β, via the glymphatic system. Since P. gingivalis can transmigrate to the brain and modulate organ-specific inflammatory innate and adaptive immune responses, this paper explores whether better management of indigenous periodontal bacteria could delay/prevent the onset and/or progression of dementia.

Can Musical or Painting Interventions Improve Chronic Pain, Mood, Quality of Life, and Cognition in Patients with Mild Alzheimer's Disease? Evidence from a Randomized Controlled Trial. - Pongan, Elodie; Tillmann, Barbara; Leveque, Yohana; Trombert, Béatrice; Getenet, Jean Claude; Auguste, Nicolas; Dauphinot, Virginie; El Haouari, Hanane; Navez, Malou; Dorey, Jean-Michel; Krolak-Salmon, Pierre; Laurent, Bernard; et al. (J Alzheimers Dis, 2017)
BACKGROUND: Among non-pharmacological therapies, musical intervention is often used for patients with Alzheimer's disease (AD) and patients presenting chronic pain. However, their efficacy is still under debate. OBJECTIVE: Our aim was to determine the efficacy of choral singing versus painting sessions on chronic pain, mood, quality of life, and cognition in AD patients. METHODS: In this multicenter randomized controlled trial, 59 mild AD patients were randomized to a 12-week singing (SG; n = 31) or painting group (PG; n = 28). Chronic pain, anxiety, depression, and quality of life were assessed before, after, and 1 month after the sessions. Cognitive abilities were assessed before and after interventions. The evolution of these different measures was assessed with mixed linear models. The primary data analysis was by intention-to-treat, and completed by a 'per protocol' approach. RESULTS: Both singing and painting interventions led to significant pain reduction (Time effect: F = 4.71; p = 0.01), reduced anxiety (Time effect: F = 10.74; p < 0.0001), improved Quality of Life (Time effect: F = 6.79; p = 0.002), improved digit span (F = 12.93; p = 0.001), and inhibitory processes (Time effect: F = 4.93; p = 0.03). Depression was reduced over time in PG only (Time x Group effect: F = 4.53; p = 0.01). Verbal Memory performance remained stable over time in SG, but decreased in PG (Time x group effect: F = 9.29; p = 0.004). CONCLUSION: Findings suggest that singing and painting interventions may reduce pain and improve mood, quality of life, and cognition in patients with mild AD, with differential effects of painting for depression and singing for memory performance.

Capsaicin Attenuates Amyloid-β-Induced Synapse Loss and Cognitive Impairments in Mice. - Chen, Long; Huang, Zhilin; Du, Yehong; Fu, Min; Han, Huili; Wang, Yutian; Dong, Zhifang (J Alzheimers Dis, 2017)
Alzheimer's disease (AD) is the most common cause of progressive cognitive impairment in the aged. The aggregation of the amyloid β-protein (Aβ) is a hallmark of AD and is linked to synapse loss and cognitive impairment. Capsaicin, a specific agonist of the transient receptor potential vanilloid 1 (TRPV1), has been proven to ameliorate stress-induced AD-like pathological and cognitive impairments, but it is unclear whether TRPV1 activation can affect cognitive and synaptic functions in Aβ-induced mouse model of AD. In this study, we investigated the effects of TRPV1 activation on spatial memory and synaptic plasticity in mice treated with Aβ. To induce AD-like pathological and cognitive impairments, adult C57Bl/6 mice were microinjected with Aβ42 (100 μM, 2.5 μl/mouse, i.c.v.). Two weeks after Aβ42 microinjection, spatial learning and memory as well as hippocampal long-term potentiation (LTP) were examined. The results showed that Aβ42 microinjection significantly impaired spatial learning and memory in the Morris water maze and novel object recognition tests compared with controls. These behavioral changes were accompanied by synapse loss and impaired LTP in the CA1 area of hippocampus. More importantly, daily capsaicin (1 mg/kg, i.p.) treatment throughout the experiment dramatically improved spatial learning and memory and synaptic function, as reflected by enhanced hippocampal LTP and reduced synapse loss, whereas the TRPV1 antagonist capsazepine (1 mg/kg, i.p.) treatment had no effects on cognitive and synaptic function in Aβ42-treated mice. These results indicate that TRPV1 activation by capsaicin rescues cognitive deficit in the Aβ42-induced mouse model of AD both structurely and functionally.

Cerebral Amyloid Angiopathy-Related Microbleeds and Cerebrospinal Fluid Biomarkers in Alzheimer's Disease. - Noguchi-Shinohara, Moeko; Komatsu, Junji; Samuraki, Miharu; Matsunari, Ichiro; Ikeda, Tokuhei; Sakai, Kenji; Hamaguchi, Tsuyoshi; Ono, Kenjiro; Nakamura, Hiroyuki; Yamada, Masahito (J Alzheimers Dis, 2017)
BACKGROUND: Alzheimer's disease (AD) commonly accompanies cerebral amyloid angiopathy (CAA). OBJECTIVE: We aimed to reveal associations between CAA-related brain microbleeds and cerebrospinal fluid (CSF) markers in AD patients. METHODS: Patients with probable AD (n = 88) from consecutive patients in our memory clinic were evaluated for patient demographics, vascular risk factors, neuropsychological tests, apolipoprotein E phenotype, MRI including T2*-weighted image and fluid attenuated inversion recovery sequence, and CSF amyloid and tau markers. RESULTS: The 88 patients with AD included 15 with microbleeds only in cortical/subcortical regions (cortical microbleeds) that could be CAA-related, 16 with microbleeds only in deep locations (deep microbleeds), 3 with microbleeds in both cortical and deep locations (mixed microbleeds), and 54 without microbleeds. The CSF levels of amyloid β-protein 1-40 (Aβ40) and amyloid β-protein 1-42 (Aβ42) were significantly lower in patients with cortical microbleeds than in those without microbleeds (p = 0.001 and p = 0.027, respectively). The result remained unchanged after adjustment for age, sex, apolipoprotein E E4 presence, and leukoaraiosis. CONCLUSIONS: CAA-related cortical microbleeds would be associated with lower CSF levels of Aβ40 and Aβ42 in AD, reflecting the deposition of both Aβ40 and Aβ42 in the cerebrovasculature.

Cerebral Hemodynamics in Mild Cognitive Impairment: A Systematic Review. - Beishon, Lucy; Haunton, Victoria J; Panerai, Ronney B; Robinson, Thompson G (J Alzheimers Dis, 2017)
BACKGROUND: The incidence of dementia is projected to rise over the coming decades, but with no sensitive diagnostic tests available. Vascular pathology precedes the deposition of amyloid and is an attractive early target. OBJECTIVE: The aim of this review was to investigate the use of cerebral hemodynamics and oxygenation as a novel biomarker for mild cognitive impairment (MCI), focusing on transcranial Doppler ultrasonography (TCD) and near-infrared spectroscopy (NIRS). METHODS: 2,698 articles were identified from Medline, Embase, PsychINFO, and Web of Science databases. 306 articles were screened and quality assessed independently by two reviewers; 26 met the inclusion criteria. Meta-analyses were performed for each marker with two or more studies and limited heterogeneity. RESULTS: Eleven studies were TCD, 8 NIRS, 5 magnetic resonance imaging, and 2 positron/single photon emission tomography. Meta-analyses showed reduced tissue oxygenation index, cerebral blood flow and velocity, with higher pulsatility index, phase and cerebrovascular resistance in MCI compared to controls. The majority of studies found reduced CO2 reactivity in MCI, with mixed findings in neuroactivation studies. CONCLUSION: Despite small sample sizes and heterogeneity, meta-analyses demonstrate clear abnormalities in cerebral hemodynamic and oxygenation parameters, even at an early stage of cognitive decline. Further work is required to investigate the use of cerebral hemodynamic and oxygenation parameters as a sensitive biomarker for dementia.

Cerebral Oxidative Stress and Microvasculature Defects in TNF-α Expressing Transgenic and Porphyromonas gingivalis-Infected ApoE-/- Mice. - Rokad, Farheen; Moseley, Ryan; Hardy, Rowan S; Chukkapalli, Sasanka; Crean, StJohn; Kesavalu, Lakshmyya; Singhrao, Sim K (J Alzheimers Dis, 2017)
The polymicrobial dysbiotic subgingival biofilm microbes associated with periodontal disease appear to contribute to developing pathologies in distal body sites, including the brain. This study examined oxidative stress, in the form of increased protein carbonylation and oxidative protein damage, in the tumor necrosis factor-α (TNF-α) transgenic mouse that models inflammatory TNF-α excess during bacterial infection; and in the apolipoprotein knockout (ApoE-/-) mouse brains, following Porphyromonas gingivalis gingival monoinfection. Following 2,4-dinitrophenylhydrazine derivatization, carbonyl groups were detected in frontal lobe brain tissue lysates by immunoblotting and immunohistochemical analysis of fixed tissue sections from the frontotemporal lobe and the hippocampus. Immunoblot analysis confirmed the presence of variable carbonyl content and oxidative protein damage in all lysates, with TNF-α transgenic blots exhibiting increased protein carbonyl content, with consistently prominent bands at 25 kDa (p = 0.0001), 43 kDa, and 68 kDa, over wild-type mice. Compared to sham-infected ApoE-/- mouse blots, P. gingivalis-infected brain tissue blots demonstrated the greatest detectable protein carbonyl content overall, with numerous prominent bands at 25 kDa (p = 0.001) and 43 kDa (p = 0.0001) and an exclusive band to this group between 30-43 kDa* (p = 0.0001). In addition, marked immunostaining was detected exclusively in the microvasculature in P. gingivalis-infected hippocampal tissue sections, compared to sham-infected, wild-type, and TNF-α transgenic mice. This study revealed that the hippocampal microvascular structure of P. gingivalis-infected ApoE-/- mice possesses elevated oxidative stress levels, resulting in the associated tight junction proteins being susceptible to increased oxidative/proteolytic degradation, leading to a loss of functional integrity.

Cerebrospinal Fluid Biomarkers and Clinical Progression in Patients with Subjective Cognitive Decline and Mild Cognitive Impairment. - Wolfsgruber, Steffen; Polcher, Alexandra; Koppara, Alexander; Kleineidam, Luca; Frölich, Lutz; Peters, Oliver; Hüll, Michael; Rüther, Eckart; Wiltfang, Jens; Maier, Wolfgang; Kornhuber, Johannes; Lewczuk, Piotr; et al. (J Alzheimers Dis, 2017)
BACKGROUND: There is very limited data on the prevalence of abnormal cerebrospinal fluid (CSF) biomarkers of Alzheimer's disease (AD) and their predictive value for clinical progression in memory clinic patients with subjective cognitive decline (SCD). OBJECTIVE: To assess the frequency of abnormal CSF biomarkers of AD and their predictive value for clinical progression in memory clinic patients with SCD in comparison to patients with mild cognitive impairment (MCI) from the same cohort. METHODS: We analyzed prospective data from memory clinic patients of the German Competence Network Dementia cohort with a baseline diagnosis of SCD (n = 82) or MCI (n = 134), distinguished by actuarial neuropsychological MCI criteria ("Jak-Bondi criteria"). Risk of clinical progression during 3-year follow-up was evaluated with Cox-Proportional-Hazard models. RESULTS: Prevalence of abnormal values in CSF markers of tau-mediated neurodegeneration (67.8% versus 46.3%) but not of amyloid deposition (40.3% versus 35.4%) was significantly higher in MCI compared to SCD. The rate of incident AD dementia (26.1% versus 12.2%) was also significantly higher in MCI. In SCD, additional 22% progressed to MCI during follow-up. Combined amyloid/tau abnormality was the strongest predictor of clinical progression in both groups. CONCLUSION: High prevalence of biomarker abnormality and clinical progression, together with the predictive value of CSF biomarkers, in memory clinic patients with SCD support the validity and usefulness of this condition as a "pre-MCI" at risk stage of AD.

Cerebrospinal Fluid Biomarkers for Alzheimer's Disease: A View of the Regulatory Science Qualification Landscape from the Coalition Against Major Diseases CSF Biomarker Team. - Arnerić, Stephen P; Batrla-Utermann, Richard; Beckett, Laurel; Bittner, Tobias; Blennow, Kaj; Carter, Leslie; Dean, Robert; Engelborghs, Sebastiaan; Genius, Just; Gordon, Mark Forrest; Hitchcock, Janice; Kaplow, June; et al. (J Alzheimers Dis, 2017)
Alzheimer's disease (AD) drug development is burdened with the current requirement to conduct large, lengthy, and costly trials to overcome uncertainty in patient progression and effect size on treatment outcome measures. There is an urgent need for the discovery, development, and implementation of novel, objectively measured biomarkers for AD that would aid selection of the appropriate subpopulation of patients in clinical trials, and presumably, improve the likelihood of successfully evaluating innovative treatment options. Amyloid deposition and tau in the brain, which are most commonly assessed either in cerebrospinal fluid (CSF) or by molecular imaging, are consistently and widely accepted. Nonetheless, a clear gap still exists in the accurate identification of subjects that truly have the hallmarks of AD. The Coalition Against Major Diseases (CAMD), one of 12 consortia of the Critical Path Institute (C-Path), aims to streamline drug development for AD and related dementias by advancing regulatory approved drug development tools for clinical trials through precompetitive data sharing and adoption of consensus clinical data standards. This report focuses on the regulatory process for biomarker qualification, briefly comments on how it contrasts with approval or clearance of companion diagnostics, details the qualifications currently available to the field of AD, and highlights the current challenges facing the landscape of CSF biomarkers qualified as hallmarks of AD. Finally, it recommends actions to accelerate regulatory qualification of CSF biomarkers that would, in turn, improve the efficiency of AD therapeutic development.

Cerebrospinal Fluid Neurogranin as a Biomarker of Neurodegenerative Diseases: A Cross-Sectional Study. - Lista, Simone; Toschi, Nicola; Baldacci, Filippo; Zetterberg, Henrik; Blennow, Kaj; Kilimann, Ingo; Teipel, Stefan J; Cavedo, Enrica; Dos Santos, Antonio Melo; Epelbaum, Stéphane; Lamari, Foudil; Dubois, Bruno; et al. (J Alzheimers Dis, 2017)
We investigated cerebrospinal fluid (CSF) concentrations of the postsynaptic biomarker neurogranin at baseline in cognitively healthy controls (HC) compared to individuals with mild cognitive impairment (MCI), patients with Alzheimer's disease (AD) dementia, and patients with frontotemporal dementia (FTD). CSF neurogranin was quantified using an in-house immunoassay in a cross-sectional multicenter study of 108 participants [AD dementia (n = 35), FTD (n = 9), MCI (n = 41), cognitively HC (n = 23)]. CSF neurogranin concentrations were significantly higher in AD patients compared with both HC subjects and FTD patients, suggesting that increased CSF neurogranin concentrations may indicate AD-related pathophysiology. CSF neurogranin was independently associated with both total tau and hyperphosphorylated tau proteins, whereas a non-significant correlation with the 42-amino acid-long amyloid-β peptide was evident. CSF neurogranin, however, was not superior to core AD biomarkers in differentiating HC from the three diagnostic groups, and it did not improve their diagnostic accuracy. We conclude that further classification and longitudinal studies are required to shed more light into the potential role of neurogranin as a pathophysiological biomarker of neurodegenerative diseases.

Challenges and Considerations Related to Studying Dementia in Blacks/African Americans. - Ighodaro, Eseosa T; Nelson, Peter T; Kukull, Walter A; Schmitt, Frederick A; Abner, Erin L; Caban-Holt, Allison; Bardach, Shoshana H; Hord, Derrick C; Glover, Crystal M; Jicha, Gregory A; Van Eldik, Linda J; Byrd, Alexander X; et al. (J Alzheimers Dis, 2017)
Blacks/African Americans have been reported to be ∼2-4 times more likely to develop clinical Alzheimer's disease (AD) compared to Whites. Unfortunately, study design challenges (e.g., recruitment bias), racism, mistrust of healthcare providers and biomedical researchers, confounders related to socioeconomic status, and other sources of bias are often ignored when interpreting differences in human subjects categorized by race. Failure to account for these factors can lead to misinterpretation of results, reification of race as biology, discrimination, and missed or delayed diagnoses. Here we provide a selected historical background, discuss challenges, present opportunities, and suggest considerations for studying health outcomes among racial/ethnic groups. We encourage neuroscientists to consider shifting away from using biologic determination to interpret data, and work instead toward a paradigm of incorporating both biological and socio-environmental factors known to affect health outcomes with the goal of understanding and improving dementia treatments for Blacks/African Americans and other underserved populations.

Change in Odor Identification Impairment is Associated with Improvement with Cholinesterase Inhibitor Treatment in Mild Cognitive Impairment. - Devanand, D P; Lentz, Cody; Chunga, Richard E; Ciarleglio, Adam; Scodes, Jennifer M; Andrews, Howard; Schofield, Peter W; Stern, Yaakov; Huey, Edward D; Bell, Karen; Pelton, Gregory H (J Alzheimers Dis, 2017)
BACKGROUND: Anticholinergic challenge can induce odor identification impairment that indicates Alzheimer's disease pathology. OBJECTIVE: To determine if decline in odor identification ability with anticholinergic challenge can predict improvement with donepezil, a cholinesterase inhibitor (ChEI), in patients with mild cognitive impairment (MCI). METHODS: At baseline, the University of Pennsylvania Smell identification Test (UPSIT) was administered before and after an anticholinergic atropine nasal spray challenge. Donepezil was started at 5 mg daily, increased to 10 mg daily if tolerated, and then the dose was kept constant for 52 weeks. Main outcomes were change in Selective Reminding Test (SRT) total immediate recall and ADAS-Cog total score from baseline to 26 and 52 weeks. RESULTS: In 37 participants, mean age 70.4 (SD 9.8) y, greater atropine-induced decrease in UPSIT score at baseline was associated with greater improvement in SRT total recall score from baseline to 26 and 52 weeks (p < 0.03). This effect remained after adjusting for time, age, education, gender, APOE ɛ4 status, and baseline cognitive score (p < 0.05). Decrease in UPSIT score was associated with global improvement (CIBIC-plus) over 52 weeks (p < 0.02). After excluding patients with congential anosmia, increase in UPSIT score from 0 to 8 weeks showed a trend-level association with improvement on the ADAS-Cog (p = 0.07). CONCLUSIONS: Anticholinergic challenge-induced odor identification decline was associated with cognitive improvement, and short-term improvement in odor identification tended to predict longer term cognitive improvement. These simple inexpensive strategies have the potential to improve selection of patients with MCI for ChEI treatment.

Chinese Calligraphy Writing for Augmenting Attentional Control and Working Memory of Older Adults at Risk of Mild Cognitive Impairment: A Randomized Controlled Trial. - Chan, Sam C C; Chan, Chetwyn C H; Derbie, Abiot Y; Hui, Irene; Tan, Davynn G H; Pang, Marco Y C; Lau, Stephen C L; Fong, Kenneth N K (J Alzheimers Dis, 2017)
BACKGROUND: Nonpharmacological intervention for individuals with mild cognitive impairment (MCI) needs further investigation. OBJECTIVE: Test efficacy of an eight-week Chinese calligraphy writing training course in improving attentional control and working memory. METHODS: Ninety-nine participants with MCI were randomized into the eight-week calligraphy writing (n = 48) or control (tablet computer) training (n = 51). Outcomes of the interventions were attentional control, working memory, visual scan and processing speed. They were measured at baseline, post-training, and six-month follow-up. RESULTS: Calligraphy writing, when compared with control, significantly improved working memory as reflected from DST-Backward sequence (p = 0.009) and span scores (p = 0.002), and divided attention as reflected from CTT2 (p < 0.001), and at the post-training. The unique improvement in working memory (span: p < 0.001; sequence: p = 0.008) of the intervention group was also found at follow-up when comparing with those at baseline. Changes in the other outcome measures were not statistically significant. CONCLUSION: The findings provide support that Chinese calligraphy writing training for eight weeks using a cognitive approach would improve working memory and to a lesser extent attentional control functions of patients with early MCI. They also demonstrate the usefulness of using mind-and-body practice for improving specific cognitive functions.

Cholinergic Modification of Neurogenesis and Gliosis Improves the Memory of AβPPswe/PSEN1dE9 Alzheimer's Disease Model Mice Fed a High-Fat Diet. - Matsuda, Takeshi; Hisatsune, Tatsuhiro (J Alzheimers Dis, 2017)
We previously reported that neuroinflammation contributes to the amnesia of AβPPswe/PSEN1dE9 Alzheimer's disease model mice fed a high-fat diet to induce type-2 diabetes (T2DM-AD mice), but the underlying mechanism for the memory decline remained unclear. Recent studies have suggested that cholinergic modulation is involved in neuroinflammatory cellular reactions including neurogenesis and gliosis, and in memory improvement. In this study, we administered a broad-spectrum cholinesterase inhibitor, rivastigmine (2 mg/kg/day, s.c.), into T2DM-AD mice for 6 weeks, and evaluated their memory performance, neurogenesis, and neuroinflammatory reactions. By two hippocampal-dependent memory tests, the Morris water maze and contextual fear conditioning, rivastigmine improved the memory deterioration of the T2DM-AD mice (n = 8, p < 0.01). The number of newborn neurons in the hippocampal dentate gyrus was 1138±324 (Ave±SEM) in wild-type littermates, 2573±442 in T2DM-AD-Vehicle, and 2165±300 in T2DM-AD-Rivastigmine mice, indicating that neurogenesis was accelerated in the two T2DM-AD groups (n = 5, p < 0.05). The dendritic maturation of new neurons in T2DM-AD-Vehicle mice was severely abrogated, and rivastigmine treatment reversed this retarded maturation. In addition, the hippocampus of T2DM-AD-Vehicle mice showed increased proinflammatory cytokines IL-1β and TNF-α and gliosis, and rivastigmine treatment blocked these inflammatory reactions. Rivastigmine did not change the insulin abnormality or amyloid pathology in these mice. Thus, cholinergic modulation by rivastigmine treatment led to enhanced neurogenesis and the suppression of gliosis, which together ameliorated the memory decline in T2DM-AD model mice.

Chromatin-Bound Oxidized α-Synuclein Causes Strand Breaks in Neuronal Genomes in in vitro Models of Parkinson's Disease. - Vasquez, Velmarini; Mitra, Joy; Hegde, Pavana M; Pandey, Arvind; Sengupta, Shiladitya; Mitra, Sankar; Rao, K S; Hegde, Muralidhar L (J Alzheimers Dis, 2017)
Alpha-synuclein (α-Syn) overexpression and misfolding/aggregation in degenerating dopaminergic neurons have long been implicated in Parkinson's disease (PD). The neurotoxicity of α-Syn is enhanced by iron (Fe) and other pro-oxidant metals, leading to generation of reactive oxygen species in PD brain. Although α-Syn is predominantly localized in presynaptic nerve terminals, a small fraction exists in neuronal nuclei. However, the functional and/or pathological role of nuclear α-Syn is unclear. Following up on our earlier report that α-Syn directly binds DNA in vitro, here we confirm the nuclear localization and chromatin association of α-Syn in neurons using proximity ligation and chromatin immunoprecipitation analysis. Moderate (∼2-fold) increase in α-Syn expression in neural lineage progenitor cells (NPC) derived from induced pluripotent human stem cells (iPSCs) or differentiated SHSY-5Y cells caused DNA strand breaks in the nuclear genome, which was further enhanced synergistically by Fe salts. Furthermore, α-Syn required nuclear localization for inducing genome damage as revealed by the effect of nucleus versus cytosol-specific mutants. Enhanced DNA damage by oxidized and misfolded/oligomeric α-Syn suggests that DNA nicking activity is mediated by the chemical nuclease activity of an oxidized peptide segment in the misfolded α-Syn. Consistent with this finding, a marked increase in Fe-dependent DNA breaks was observed in NPCs from a PD patient-derived iPSC line harboring triplication of the SNCA gene. Finally, α-Syn combined with Fe significantly promoted neuronal cell death. Together, these findings provide a novel molecular insight into the direct role of α-Syn in inducing neuronal genome damage, which could possibly contribute to neurodegeneration in PD.

Chronic Neurodegenerative Illnesses and Epilepsy in Danish Adventists and Baptists: A Nationwide Cohort Study. - Thygesen, Lau Caspar; Gimsing, Louise NØrreslet; Bautz, Andrea; Hvidt, Niels Christian; Johansen, Christoffer (J Alzheimers Dis, 2017)
BACKGROUND: Limited knowledge of the influence of lifestyle risk factors and religious living on chronic neurological diseases exist. Seventh-day Adventists (SDA) do not consume tobacco, alcohol, or pork, and many adhere to lacto-ovo-vegetarian diet, and Baptists discourage excessive use of alcohol and tobacco. OBJECTIVE: We investigated whether the incidence of four common chronic neurological illnesses: dementia, Alzheimer's disease, Parkinson's disease, and epilepsy in a large cohort of Danish Adventists and Baptists was different compared to the general Danish population. Three of the illnesses are neurodegenerative, whereas epilepsy can occur at any age. METHODS: We compared hospital admission rates for some major neurological diseases among members of the Danish Religious Societies Health Study comprising 6,532 SDA and 3,720 Baptists with the general Danish population. Standardized incidence rates (SIR) stratified by sex, age, and calendar time were calculated. RESULTS: SIR of dementia or Alzheimer's disease was significantly decreased for members of both communities (SDA, 0.78; 95% CI, 0.67-#x2013;0.90 and Baptists, 0.59; 0.47-#x2013;0.73). The SIRs of Parkinson's disease and epilepsy were not significantly different compared to the general population. CONCLUSIONS: We observe reduced incidence for dementia or Alzheimer's disease in a large cohort of members of two religious communities characterized by lifestyle recommendations. More studies are needed to disentangle the interaction between such lifestyle and other components of the religious belief system.

Chronic Verubecestat Treatment Suppresses Amyloid Accumulation in Advanced Aged Tg2576-AβPPswe Mice Without Inducing Microhemorrhage. - Villarreal, Stephanie; Zhao, Fuqiang; Hyde, Lynn A; Holder, Daniel; Forest, Thomas; Sondey, Marie; Chen, Xia; Sur, Cyrille; Parker, Eric M; Kennedy, Matthew E (J Alzheimers Dis, 2017)
Verubecestat is a potent BACE1 enzyme inhibitor currently being investigated in Phase III trials for the treatment of mild-to-moderate and prodromal Alzheimer's disease. Multiple anti-amyloid immunotherapies have been dose-limited by adverse amyloid related imaging abnormalities such as vasogenic edema (ARIA-E) and microhemorrhage (ARIA-H) observed in human trials and mice. Verubecestat was tested in a 12-week nonclinical study for the potential to exacerbate microhemorrhage (ARIA-H) profiles in 18-22-month-old post-plaque Tg2576-AβPPswe mice. Animals were treated with verubecestat or controls including the anti-Aβ antibody analog of bapineuzumab (3D6) as a positive control for ARIA induction. ARIA-H was measured using in-life longitudinal T2*-MRI and Prussian blue histochemistry at study end. Verubecestat reduced plasma and cerebrospinal fluid Aβ40 and Aβ42 by >90% and 62% to 68%, respectively. The ARIA-H profile of verubecestat-treated mice was not significantly different than controls. Anti-Aβ treatment significantly increased ARIA-H detected by Prussian blue staining; however, anti-Aβ antibody treatment did not impact plaque status. Verubecestat treatment significantly suppressed the accumulation of total levels of brain Aβ40 and Aβ42 and Thioflavin S positive plaque load. Stereological analysis of cortex and hippocampus plaque load similarly revealed significantly reduced area of Aβ immunoreactivity and reduced plaque number in verubecestat-treated animals compared to controls. The absence of elevated ARIA events in verubecestat-treated mice was associated with a significant reduction in the level of accumulated CNS amyloid pathology and brain Aβ peptides; effects consistent with the desired therapeutic mechanism of verubecestat in AD patients. These data will be compared with longitudinal MRI profiles from ongoing clinical trials.

Chronotropic Response and Cognitive Function in a Cohort at Risk for Alzheimer's Disease. - Law, Lena L; Schultz, Stephanie A; Boots, Elizabeth A; Einerson, Jean A; Dougherty, Ryan J; Oh, Jennifer M; Korcarz, Claudia E; Edwards, Dorothy F; Koscik, Rebecca L; Dowling, N Maritza; Gallagher, Catherine L; Bendlin, Barbara B; et al. (J Alzheimers Dis, 2017)
The objective of this study was to examine the association of chronotropic response (CR) and heart rate (HR) recovery- two indices of cardiovascular function within the context of a graded exercise test- with cognitive performance in a cognitively healthy, late-middle-aged cohort at risk for Alzheimer's disease (AD). Ninety participants (age = 63.52±5.86 years; 65.6% female) from the Wisconsin Registry for Alzheimer's Prevention participated in this study. They underwent graded exercise testing and a comprehensive neuropsychological assessment that assessed the following four cognitive domains: Immediate Memory, Verbal & Learning Memory, Working Memory, and Speed & Flexibility. Regression analyses, adjusted for age, sex, and education, were used to examine the association between CR, HR recovery, and cognition. We found significant associations between CR and cognitive performance in the domains of Immediate Memory, Verbal Learning & Memory, and Speed & Flexibility. In contrast, HR recovery was not significantly associated with cognitive function. The association between CR and cognition persisted even after controlling for HR recovery. Together, these findings indicatethat, in a cognitively normal, late-middle-aged cohort, CR is a stronger correlate of cognitive performance than HR recovery. Overall, this study reinforces the idea that cardiovascular health plays an important role in cognitive function, specifically in a cohort at risk for AD; and that interventions that promote vascular health may be a viable pathway to preventing or slowing cognitive decline due to AD.

Cognitive and Neuroanatomical Correlates in Early Versus Late Onset Parkinson's Disease Dementia. - Kim, Younggwang; Lee, Dongkyun; Cho, Kyoo Ho; Lee, Jae Jung; Ham, Jee Hyun; Ye, Byoung Seok; Lee, Seung-Koo; Lee, Jong-Min; Sohn, Young H; Lee, Phil Hyu (J Alzheimers Dis, 2017)
BACKGROUND: Aging is the most important risk factor of development of dementia in Parkinson's disease (PD), but there are no data on clinical and radiological heterogeneity of PD dementia (PDD) depending on age at onset. OBJECTIVES: The goal of this study was to examine whether patients with PDD are clinically and radiologically heterogeneous depending on age at onset. METHODS: A total of 116 patients with PD dementia and 121 age- and sex-matched normal controls were enrolled. The subjects were divided into early-onset (EOPDD; n = 39) and late-onset (LOPDD; n = 77) PDD with the respective age-matched control group based on a cutoff value of 70 years. The effects of diagnosis, age, and their interaction on neuropsychological tests, cortical thickness, and substantia innominata volume were assessed using analysis of covariance. RESULTS: EOPDD patients had a poorer cognitive performance on digit backward, forward span test (p = 0.011 and 0.05), and visual recognition memory function (p = 0.012) compared with LOPDD patients. Additionally, EOPDD patients exhibited cortical thinning in the left anterior cingulate gyrus and the right inferior temporal gyrus, with significantly decreased normalized substantia innominata volume (p = 0.044). CONCLUSIONS: Our data demonstrated that EOPDD patients exhibit poorer cognitive performance and more severe atrophy in the cortex and substantia innominata, implying that EOPDD may be a distinct phenotype different from LOPDD.

Cognitive Change in Rehabilitation Patients with Dementia: Prevalence and Association with Rehabilitation Success. - Dutzi, Ilona; Schwenk, Michael; Kirchner, Marietta; Bauer, Jürgen M; Hauer, Klaus (J Alzheimers Dis, 2017)
BACKGROUND: Dementia is a frequent diagnosis in geriatric rehabilitation. Studies in patients with dementia on the development of their cognitive status during rehabilitation and its relation to functional outcomes have been scarce. OBJECTIVES: To describe the changes in cognitive status in patients with dementia during inpatient rehabilitation and to determine its association with patient characteristics and rehabilitation outcome. METHODS: Cohort study in a geriatric rehabilitation center with data collection at admission and discharge. Outcome measures were change in global and domain-related cognitive functioning and its association with activities of daily living (ADL) and discharge home. RESULTS: 154 patients (mean age 83.7 years) diagnosed with mild to moderate dementia were included. Cognitive performance significantly improved from admission to discharge for all cognitive variables tested (p < 0.001 to 0.03). Change in global cognitive functioning, executive functions, and episodic memory were positively associated with ADL recovery. Change in global cognitive functioning predicted ADL improvements (β= 0.32; p = 0.006). Only 7.8% of patients, characterized by worse ADL and motor abilities as well as higher frailty scores at admission, deteriorated in global cognitive scores. In comparison to patients with stable or improved cognition, these patients showed least improvements in ADL-scores (4.1 versus 12.5) and a trend for higher institutionalization (50% versus 26.5%). CONCLUSIONS: The findings highlight the potential of patients with dementia to recover cognitive functioning during rehabilitation. Cognitive change represents an independent rehabilitation outcome and a prognostic factor for successful rehabilitation suggesting that specific interventions are indicated to maintain and enhance cognitive functioning in these highly vulnerable patients.

Cognitive Composites Domain Scores Related to Neuroimaging Biomarkers within Probable-Amnestic Mild Cognitive Impairment-Storage Subtype. - Espinosa, Ana; Alegret, Montserrat; Pesini, Pedro; Valero, Sergi; Lafuente, Asunción; Buendia, Mar; San José, Itziar; Ibarria, Marta; Tejero, Miguel A; Giménez, Joan; Ruiz, Susana; Hernandez, Isabel; et al. (J Alzheimers Dis, 2017)
The probable-amnestic (Pr-a) mild cognitive impairment (MCI)-storage subtype is a phenotype with 8.5 times more risk of conversion to dementia, mainly Alzheimer's disease (AD), than the possible non-amnestic (Pss-na) MCI. The aim of this study was to find the optimized cognitive composites (CCs) domain scores most related to neuroimaging biomarkers within Pr-aMCI-storage subtype patients. The Fundació ACE (ACE) study with 20 Pr-aMCI-storage subtype subjects (MCI) were analyzed. All subjects underwent a neuropsychological assessment, a structural MRI, FDG-PET, and PIB-PET. The adjusted hippocampal volume (aHV) on MRI, the standard uptake value ratio (SUVR) on FDG-PET and PIB-PET SUVR measures were analyzed. The construction of the CCs domain scores, and the aHV on MRI and FDG-PET SUVR measures, were replicated in the parental AB255 study database (n = 133 MCI). Partial correlations adjusted by age, gender, and education were calculated with the associated p-value among every CC domain score and the neuroimaging biomarkers. The results were replicated in the "MCI due to AD" with memory storage impairments from ADNI. Delayed Recall CC domain score was significantly correlated with PIB-PET SUVR (β= -0.61, p = 0.003) in the ACE study and also with aHV on MRI (β= 0.27, p = 0.01) and FDG-PET SUVR (β= 0.27, p = 0.01) in the AB255 study. After a median survival time of 20.6 months, 85% from the ACE MCI converted to AD. The replication of our results in the ADNI dataset also confirmed our findings. Delayed Recall is the CC domain score best correlated with neuroimaging biomarkers associated with prodromal AD diagnosis.

Cognitive Status, Gray Matter Atrophy, and Lower Orthostatic Blood Pressure in Older Adults. - O'Hare, Celia; Kenny, Rose-Anne; Aizenstein, Howard; Boudreau, Robert; Newman, Anne; Launer, Lenore; Satterfield, Suzanne; Yaffe, Kristine; Rosano, Caterina (J Alzheimers Dis, 2017)
BACKGROUND: Associations between orthostatic blood pressure and cognitive status (CS) have been described with conflicting results. OBJECTIVE: We hypothesize that long-term exposure to lower orthostatic blood pressure is related to having worse CS later in life and that atrophy of regions involved in central regulation of autonomic function mediate these associations. METHODS: Three-to-four measures of orthostatic blood pressure were obtained from 1997-2003 in a longitudinal cohort of aging, and average systolic orthostatic blood pressure response (ASOBPR) was computed as % change in systolic blood pressure from sit-to-stand measured at one minute post stand. CS was determined in 2010-2012 by clinician-adjudication (n = 240; age = 87.1±2.6; 59% women; 37% black) with a subsample also undergoing concurrent structural neuroimaging (n = 129). Gray matter volume of regions related to autonomic function was measured. Multinomial regression was used to compare ASOBPR in those who were cognitively intact versus those with a diagnosis of mild cognitive impairment or dementia, controlling for demographics, trajectories of seated blood pressure, incident cardiovascular risk/events and medications measured from 1997 to 2012. Models were repeated in the subsample with neuroimaging, before and after adjustment for regional gray matter volume. RESULTS: There was an inverse association between ASOBPR and probability of dementia diagnosis (9% lower probability for each % point higher ASOBPR: OR 0.91, CI95%  = 0.85-0.98; p = 0.01). Associations were similar in the subgroup with neuroimaging before and after adjustment for regional gray matter volume. CONCLUSION: ASOBPR may be an early marker of risk of dementia in older adults living in the community.

Cognitive Training Interventions for Patients with Alzheimer's Disease: A Systematic Review. - Kallio, Eeva-Liisa; Öhman, Hanna; Kautiainen, Hannu; Hietanen, Marja; Pitkälä, Kaisu (J Alzheimers Dis, 2017)
BACKGROUND: Cognitive training (CT) refers to guided cognitive exercises designed to improve specific cognitive functions, as well as enhance performance in untrained cognitive tasks. Positive effects of CT on cognitive functions in healthy elderly people and persons with mild cognitive impairment have been reported, but data regarding the effects of CT in patients with dementia is unclear. OBJECTIVE: We systematically reviewed the current evidence from randomized controlled trials (RCTs) to find out if CT improves or stabilizes cognition and/or everyday functioning in patients with mild and moderate Alzheimer's disease. RESULTS: Altogether, 31 RCTs with CT as either the primary intervention or part of a broader cognitive or multi-component intervention were found. A positive effect was reported in 24 trials, mainly on global cognition and training-specific tasks, particularly when more intensive or more specific CT programs were used. Little evidence of improved everyday functioning was found. CONCLUSIONS: Despite some positive findings, the inaccurate definitions of CT, inadequate sample sizes, unclear randomization methods, incomplete datasets at follow-up and multiple testing may have inflated the results in many trials. Future high quality RCTs with appropriate classification and specification of cognitive interventions are necessary to confirm CT as an effective treatment option in Alzheimer's disease.

Colivelin Ameliorates Impairments in Cognitive Behaviors and Synaptic Plasticity in APP/PS1 Transgenic Mice. - Wu, Meina; Shi, Hui; He, Yexin; Yuan, Li; Qu, Xuesong; Zhang, Jun; Wang, Zhaojun; Cai, Hongyan; Qi, Jinshun (J Alzheimers Dis, 2017)
Alzheimer's disease (AD) is the most common cause of dementia, and effective therapeutics are lacking. Colivelin (CLN), a novel, strong humanin derivative, is effective in vitro in preventing cell death induced by AD-causative genes and amyloid-β protein (Aβ) even at a low concentration. We recently demonstrated that intrahippocampal injection of CLN prevents Aβ25-35-induced deficits in spatial memory and synaptic plasticity in normal rats. Here, we further observed the effects of chronically intranasally (i.n.) administered CLN on cognitive behaviors and pathological hallmarks in 9-month-old APPswe/PS1dE9 (APP/PS1) AD mice using multiple behavioral tests and immunochemistry. The electrophysiological mechanism of CLN neuroprotection was also investigated by recording in vivo hippocampal long-term potentiation (LTP). CLN pretreatment effectively prevented impairments in new object recognition, working memory, and long-term spatial memory and reversed the depression of in vivo hippocampal LTP in APP/PS1 mice. Additionally, chronic application of CLN obviously reduced Aβ deposition in the hippocampus in APP/PS1 mice. These results indicate that CLN has strong neuroprotective effects on learning and memory behaviors in APP/PS1 mice and that this behavioral improvement is closely associated with the reduction of Aβ deposition and alleviation of LTP suppression in the hippocampus, supporting the potential of CLN for the prevention and treatment of AD.

Combined Dual-Task Gait Training and Aerobic Exercise to Improve Cognition, Mobility, and Vascular Health in Community-Dwelling Older Adults at Risk for Future Cognitive Decline1. - Gregory, Michael A; Boa Sorte Silva, Narlon C; Gill, Dawn P; McGowan, Cheri L; Liu-Ambrose, Teresa; Shoemaker, J Kevin; Hachinski, Vladimir; Holmes, Jeff; Petrella, Robert J (J Alzheimers Dis, 2017)
This 6-month experimental case series study investigated the effects of a dual-task gait training and aerobic exercise intervention on cognition, mobility, and cardiovascular health in community-dwelling older adults without dementia. Participants exercised 40 min/day, 3 days/week for 26 weeks on a Biodex GaitTrainer2 treadmill. Participants were assessed at baseline (V0), interim (V1: 12-weeks), intervention endpoint (V2: 26-weeks), and study endpoint (V3: 52-weeks). The study outcomes included: cognition [executive function (EF), processing speed, verbal fluency, and memory]; mobility: usual & dual-task gait (speed, step length, and stride time variability); and vascular health: ambulatory blood pressure, carotid arterial compliance, and intima-media thickness (cIMT). Fifty-six participants [age: 70(6) years; 61% female] were included in this study. Significant improvements following the exercise program (V2) were observed in cognition: EF (p = 0.002), processing speed (p < 0.001), verbal fluency [digit symbol coding (p < 0.001), phonemic verbal fluency (p < 0.001)], and memory [immediate recall (p < 0.001) and delayed recall (p < 0.001)]; mobility: usual & dual-task gait speed (p = 0.002 and p < 0.001, respectively) and step length (p = 0.001 and p = 0.003, respectively); and vascular health: cIMT (p = 0.002). No changes were seen in the remaining outcomes. In conclusion, 26 weeks of dual-task gait training and aerobic exercise improved performance on a number of cognitive outcomes, while increasing usual & dual-task gait speed and step length in a sample of older adults without dementia.
Keywords: Aged; Aged, 80 and over; Analysis of Variance; Blood Pressure; Blood Pressure Monitoring, Ambulatory; Carotid Intima-Media Thickness; Cognition Disorders; Exercise; Exercise Therapy; Female; Follow-Up Studies; Gait; Humans; Independent Living; Male; Middle Aged; Neuropsychological Tests

A Common Variant of IL-6R is Associated with Elevated IL-6 Pathway Activity in Alzheimer's Disease Brains. - Haddick, Patrick C G; Larson, Jessica L; Rathore, Nisha; Bhangale, Tushar R; Phung, Qui T; Srinivasan, Karpagam; Hansen, David V; Lill, Jennie R; Pericak-Vance, Margaret A; Haines, Jonathan; Farrer, Lindsay A; Kauwe, John S; et al. (J Alzheimers Dis, 2017)
The common p.D358A variant (rs2228145) in IL-6R is associated with risk for multiple diseases and with increased levels of soluble IL-6R in the periphery and central nervous system (CNS). Here, we show that the p.D358A allele leads to increased proteolysis of membrane bound IL-6R and demonstrate that IL-6R peptides with A358 are more susceptible to cleavage by ADAM10 and ADAM17. IL-6 responsive genes were identified in primary astrocytes and microglia and an IL-6 gene signature was increased in the CNS of late onset Alzheimer's disease subjects in an IL6R allele dependent manner. We conducted a screen to identify variants associated with the age of onset of Alzheimer's disease in APOE ɛ4 carriers. Across five datasets, p.D358A had a meta P = 3 ×10-4 and an odds ratio = 1.3, 95% confidence interval 1.12 -1.48. Our study suggests that a common coding region variant of the IL-6 receptor results in neuroinflammatory changes that may influence the age of onset of Alzheimer's disease in APOE ɛ4 carriers.

Comorbidity Analysis between Alzheimer's Disease and Type 2 Diabetes Mellitus (T2DM) Based on Shared Pathways and the Role of T2DM Drugs. - Karki, Reagon; Kodamullil, Alpha Tom; Hofmann-Apitius, Martin (J Alzheimers Dis, 2017)
BACKGROUND: Various studies suggest a comorbid association between Alzheimer's disease (AD) and type 2 diabetes mellitus (T2DM) indicating that there could be shared underlying pathophysiological mechanisms. OBJECTIVE: This study aims to systematically model relevant knowledge at the molecular level to find a mechanistic rationale explaining the existing comorbid association between AD and T2DM. METHOD: We have used a knowledge-based modeling approach to build two network models for AD and T2DM using Biological Expression Language (BEL), which is capable of capturing and representing causal and correlative relationships at both molecular and clinical levels from various knowledge resources. RESULTS: Using comparative analysis, we have identified several putative "shared pathways". We demonstrate, at a mechanistic level, how the insulin signaling pathway is related to other significant AD pathways such as the neurotrophin signaling pathway, PI3K/AKT signaling, MTOR signaling, and MAPK signaling and how these pathways do cross-talk with each other both in AD and T2DM. In addition, we present a mechanistic hypothesis that explains both favorable and adverse effects of the anti-diabetic drug metformin in AD. CONCLUSION: The two computable models introduced here provide a powerful framework to identify plausible mechanistic links shared between AD and T2DM and thereby identify targeted pathways for new therapeutics. Our approach can also be used to provide mechanistic answers to the question of why some T2DM treatments seem to increase the risk of AD.

Comparative Analysis of Cortical Microinfarcts and Microbleeds using 3.0-Tesla Postmortem Magnetic Resonance Images and Histopathology. - Niwa, Atsushi; Ii, Yuichiro; Shindo, Akihiro; Matsuo, Ko; Ishikawa, Hidehiro; Taniguchi, Akira; Takase, Shinichi; Maeda, Masayuki; Sakuma, Hajime; Akatsu, Hiroyasu; Hashizume, Yoshio; Tomimoto, Hidekazu (J Alzheimers Dis, 2017)
Microvascular lesions including cortical microinfarctions (CMIs) and cerebral lobar microbleeds (CMBs) are usually caused by cerebral amyloid angiopathy (CAA) in the elderly and are correlated with cognitive decline. However, their radiological-histopathological coincidence has not been revealed systematically with widely used 3-Tesla (3T) magnetic resonance imaging (MRI). The purpose of the present study is to delineate the histopathological background corresponding to MR images of these lesions. We examined formalin-fixed 10-mm thick coronal brain blocks from 10 CAA patients (five were also diagnosed with Alzheimer's disease, three with dementia with Lewy bodies, and two with CAA only) with dementia and six non CAA patients with neurodegenerative disease. Using 3T MRI, both 3D-fluid attenuated inversion recovery (FLAIR) and 3D-double inversion recovery (DIR) were examined to identify CMIs, and T2* and susceptibility-weighted images (SWI) were examined to identify CMBs. These blocks were subsequently examined histologically and immunohistochemically. In CAA patients, 48 CMIs and 6 lobar CMBs were invariably observed in close proximity to degenerated Aβ-positive blood vessels. Moreover, 16 CMIs (33%) of 48 were detected with postmortem MRI, but none were seen when the lesion size was smaller than 1 mm. In contrast, only 1 undeniable CMI was founded with MRI and histopathology in 6 non CAA patients. Small, cortical high-intensity lesions seen on 3D-FLAIR and 3D-DIR images likely represent CMIs, and low-intensity lesions in T2* and SWI correspond to CMBs with in vivo MRI. Furthermore, a close association between amyloid-laden vessels and these microvascular lesions indicated the contribution of CAA to their pathogenesis.

Comparison of Gait Parameters for Predicting Cognitive Decline: The Mayo Clinic Study of Aging. - Savica, Rodolfo; Wennberg, Alexandra M V; Hagen, Clinton; Edwards, Kelly; Roberts, Rosebud O; Hollman, John H; Knopman, David S; Boeve, Bradley F; Machulda, Mary M; Petersen, Ronald C; Mielke, Michelle M (J Alzheimers Dis, 2017)
BACKGROUND: Previous studies reported that slower gait speed might predict cognitive impairment and dementing illnesses, supporting the role of gait speed as a possible subclinical marker of cognitive impairment. However, the predictive value of other gait parameters for cognitive decline is unclear. OBJECTIVE: To investigate and compare the association with, and prediction of, specific gait parameters for cognition in a population-based sample. METHODS: The analysis included 3,426 cognitively normal participants enrolled in the Mayo Clinic Study of Aging. At baseline and every 15 months (mean follow-up = 1.93 years), participants had a study coordinator evaluation, neurological examination, and a neuropsychological assessment using nine tests that covered four domains. Gait parameters were assessed with the GAITRite® instrument. General linear mixed effects models were used to compute the annualized rate of change in cognitive domain z-scores, controlling for age, sex, education, depression, comorbidities, body mass index, APOE ɛ4 allele, and visit number, and excluding individuals with a history of stroke, alcoholism, Parkinson's disease, subdural hematoma, and normal pressure hydrocephalus. RESULTS: Spatial (stride length), temporal (ambulatory time, gait speed, step count, cadence, double support time), and spatiotemporal (cadence) gait parameters, and greater intraindividual variability in stride length, swing time, and stance time were associated with a significant decline in global cognition and in specific domains including memory, executive function, visuospatial, and language. CONCLUSIONS: Spatial, temporal, and spatiotemporal measures of gait and greater variability of gait parameters were associated with and predictive of both global- and domain-specific cognitive decline.

Comprehensive Quantitative Profiling of Tau and Phosphorylated Tau Peptides in Cerebrospinal Fluid by Mass Spectrometry Provides New Biomarker Candidates. - Russell, Claire L; Mitra, Vikram; Hansson, Karl; Blennow, Kaj; Gobom, Johan; Zetterberg, Henrik; Hiltunen, Mikko; Ward, Malcolm; Pike, Ian (J Alzheimers Dis, 2017)
Aberrant tau phosphorylation is a hallmark in Alzheimer's disease (AD), believed to promote formation of paired helical filaments, the main constituent of neurofibrillary tangles in the brain. While cerebrospinal fluid (CSF) levels of total tau and tau phosphorylated at threonine residue 181 (pThr181) are established core biomarkers for AD, the value of alternative phosphorylation sites, which may have more direct relevance to pathology, for early diagnosis is not yet known, largely due to their low levels in CSF and lack of standardized detection methods. To overcome sensitivity limitations for analysis of phosphorylated tau in CSF, we have applied an innovative mass spectrometry (MS) workflow, TMTcalibratortrademark, to enrich and enhance the detection of phosphoproteome components of AD brain tissue in CSF, and enable the quantitation of these analytes. We aimed to identify which tau species present in the AD brain are also detectable in CSF and which, if any, are differentially regulated with disease. Over 75% coverage of full-length (2N4R) tau was detected in the CSF with 47 phosphopeptides covering 31 different phosphorylation sites. Of these, 11 phosphopeptides were upregulated by at least 40%, along with an overall increase in tau levels in the CSF of AD patients relative to controls. Use of the TMTcalibratortrademark workflow dramatically improved our ability to detect tau-derived peptides that are directly related to human AD pathology. Further validation of regulated tau peptides as early biomarkers of AD is warranted and is currently being undertaken.

Consecutive Analysis of BACE1 Function on Developing and Developed Neuronal Cells. - Kamikubo, Yuji; Takasugi, Nobumasa; Niisato, Kazue; Hashimoto, Yoshie; Sakurai, Takashi (J Alzheimers Dis, 2017)
The amyloid-β protein precursor (AβPP) is cleaved by a transmembrane protease termed β-site AβPP cleavage enzyme (BACE1), which is being explored as a target for therapy and prevention of Alzheimer's disease (AD). Although genetic deletion of BACE1 results in abolished amyloid pathology in AD model mice, it also results in neurodevelopmental phenotypes such as hypomyelination and synaptic loss, observed in schizophrenia and autism-like phenotype. These lines of evidence indicate that the inhibition of BACE1 causes adverse side effects during the neurodevelopmental stage. However, the effects of the inhibition of BACE1 activity on already developed neurons remain unclear. Here, we utilized hippocampal slice cultures as an ex vivo model that enabled continuous and long-term analysis for the effect of BACE1 inhibition on neuronal circuits and synapses. Temporal changes in synaptic proteins in hippocampal slices indicated acute synaptic loss, followed by synapse formation and maintenance phases. Long-term BACE1 inhibition in the neurodevelopmental stage caused the loss of synaptic proteins but failed to alter synaptic proteins in the already developed maintenance stage. These data indicate that BACE1 function on synapses is dependent on synaptic developmental stages, and our study provides a useful model to observe the long-term effect of BACE1 activity in the brain, and to evaluate adverse effects of BACE inhibitors.

Cortical Thickness and Microstructural White Matter Changes Detect Amnestic Mild Cognitive Impairment. - Wang, Zan; Dai, Zhengjia; Shu, Hao; Liu, Duan; Guo, Qihao; He, Yong; Zhang, Zhijun (J Alzheimers Dis, 2017)
Both the apolipoprotein E (APOE) ɛ4 allele and amnestic mild cognitive impairment (aMCI) are considered to be risk factors for Alzheimer's disease (AD). The primary aim of this study was to determine whether the aMCI-related abnormality in gray matter (GM) cortical thickness and white matter (WM) tracts integrity would be modified by the APOE genotype. A total of 146 older adults, including 64 aMCI patients (28 ɛ4 carriers and 36 non-carriers) and 82 healthy controls (39 ɛ4 carriers and 43 non-carriers), underwent a standardized clinical interview, neuropsychological battery assessment, and multi-modal brain magnetic resonance imaging scans. Compared with control subjects, the patients with aMCI showed significantly reduced cortical thickness bilaterally in the parahippocampal gyrus and disrupted WM integrity in the limbic tracts (e.g., increased mean diffusivity in the right parahippocampal cingulum and bilateral uncinate fasciculus). However, no significant main effects of the APOE genotype and diagnosis-by-genotype interaction on GM thickness and WM integrity were observed. Further, diffusivity measures of the limbic WM tracts were significantly correlated with the parahippocampal atrophy in aMCI. Importantly, the parahippocampal thickness and diffusivity measures of the limbic WM tracts were significantly correlated with the cognitive performance (i.e., episodic memory Z score) in patients with aMCI. These results demonstrate that WM microstructural disruptions in the limbic tracts are present at the early stage of AD in an APOE-independent manner; and this degeneration may occur progressively, in parallel with parahippocampal atrophy, and may specifically contribute to early initial impairment in episodic memory.

Cost-Utility of Using Alzheimer's Disease Biomarkers in Cerebrospinal Fluid to Predict Progression from Mild Cognitive Impairment to Dementia. - Handels, Ron L H; Wimo, Anders; Dodel, Richard; Kramberger, Milica G; Visser, Pieter Jelle; Molinuevo, José Luis; Verhey, Frans R J; Winblad, Bengt (J Alzheimers Dis, 2017)
BACKGROUND: Diagnostic research criteria for Alzheimer's disease support the use of biomarkers in the cerebrospinal fluid (CSF) to improve the accuracy of the prognosis regarding progression to dementia for people with mild cognitive impairment (MCI). OBJECTIVE: The aim of this study was to estimate the potential incremental cost-effectiveness ratio of adding CSF biomarker testing to the standard diagnostic workup to determine the prognosis for patients with MCI. METHODS: In an early technology assessment, a mathematical simulation model was built, using available evidence on added prognostic value as well as expert opinion to estimate the incremental costs and quality-adjusted life years (QALYs) of 20,000 virtual MCI patients with (intervention strategy) and without (control strategy) relying on CSF, from a health-care sector perspective and with a 5-year time horizon. RESULTS: Adding the CSF test improved the accuracy of prognosis by 11%. This resulted in an average QALY gain of 0.046 and € 432 additional costs per patient, representing an incremental cost-effectiveness ratio of € 9,416. CONCLUSION: The results show the potential of CSF biomarkers in current practice from a health-economics perspective. This result was, however, marked by a high degree of uncertainty, and empirical research is required into the impact of a prognosis on worrying, false-positive/negative prognosis, and stigmatization.

Decreased Expression of hsa-miR-4274 in Cerebrospinal Fluid of Normal Pressure Hydrocephalus Mimics with Parkinsonian Syndromes. - Jurjević, Ivana; Miyajima, Masakazu; Ogino, Ikuko; Akiba, Chihiro; Nakajima, Madoka; Kondo, Akihide; Kikkawa, Mika; Kanai, Mitsuyasu; Hattori, Nobutaka; Arai, Hajime (J Alzheimers Dis, 2017)
BACKGROUND: Patients presenting with the classical idiopathic normal pressure hydrocephalus (iNPH) triad often show additional parkinsonian spectrum signs. Accurate differential diagnosis strongly influences the long-term outcome of cerebrospinal fluid (CSF) shunting. OBJECTIVE: The aim of this study was to find potential CSF microRNA (miRNA) biomarkers for NPH mimics with parkinsonian syndromes that can reliably distinguish them from iNPH patients. METHODS: Two cohorts of 81 patients (cohort 1, n = 55; cohort 2, n = 26) with possible iNPH who were treated in two centers between January 2011 and May 2014 were studied. In both cohorts, CSF samples were obtained from patients clinically diagnosed with iNPH (n = 21 and n = 10, respectively), possible iNPH with parkinsonian spectrum (PS) (n = 18, n = 10, respectively), possible iNPH with Alzheimer's disease (AD) (n = 16), and non-affected elderly individuals (NC) (n = 6). A three-step qRT-PCR analysis of the CSF samples was performed to detect miRNAs that were differentially expressed in the groups. RESULTS: The expression of hsa-miR-4274 in CSF was decreased in both cohorts of PS group patients (cohort 1: p < 0.0001, cohort 2: p < 0.0001), and was able to distinguish PS from iNPH with high accuracy (area under the curve = 0.908). The CSF concentration of hsa-miR-4274 also correlated with the specific binding ratio of ioflupane (123I) dopamine transporter scan (r = -0.494, p = 0.044). By contrast, the level of hsa-miR-4274 was significantly increased in the PS group after CSF diversion. CONCLUSION: Levels of CSF hsa-miR-4274 can differentiate PS from patients with iNPH, AD, and NC. This may be clinically useful for diagnostic purposes and predicting shunt treatment responses.

Decreased Glucose Metabolism in Medial Prefrontal Areas is Associated with Nutritional Status in Patients with Prodromal and Early Alzheimer's Disease. - Sugimoto, Taiki; Nakamura, Akinori; Kato, Takashi; Iwata, Kaori; Saji, Naoki; Arahata, Yutaka; Hattori, Hideyuki; Bundo, Masahiko; Ito, Kengo; Niida, Shumpei; Sakurai, Takashi (J Alzheimers Dis, 2017)
BACKGROUND: Weight loss is frequently observed in patients with Alzheimer's disease (AD); however, the underlying mechanisms are not well understood. OBJECTS: To clarify the associations between nutritional status and AD-related brain changes using Pittsburgh Compound-B (PiB)-PET, fluorodeoxyglucose (FDG)-PET, and structural MRI. METHODS: The subjects were 34 amyloid-β (Aβ)-positive individuals with mild cognitive impairment or early AD (prodromal/early AD), and 55 Aβ-negative cognitively normal (CN) subjects who attended the Multimodal Neuroimaging for AD Diagnosis (MULNIAD) study. Nutritional status of the subjects was assessed by body mass index and waist to height ratio (waist circumference/height). The associations between nutritional status and brain changes were examined by multiple regression analysis using statistical parametric mapping. RESULTS: In the prodromal/early AD group, nutritional status was significantly positively correlated with regional cerebral glucose metabolism (rCGM) in the medial prefrontal cortices, while different topographical associations were seen in the CN group, suggesting these changes were AD-specific. Aβ deposition and gray matter volume were not significantly associated with nutritional status. Sub-analysis in the prodromal/early AD group demonstrated that fat mass index, but not fat-free mass index, was positively correlated with rCGM in the medial prefrontal areas. CONCLUSION: This present study provides preliminary results suggesting that hypometabolism in the medial prefrontal areas is specifically associated with AD-related weight loss, and decrease in fat mass may have a key role.

Delayed Recall and Working Memory MMSE Domains Predict Delirium following Cardiac Surgery. - Price, Catherine C; Garvan, Cynthia; Hizel, Loren P; Lopez, Marcos G; Billings, Frederic T (J Alzheimers Dis, 2017)
BACKGROUND: Reduced preoperative cognition is a risk factor for postoperative delirium. The significance for type of preoperative cognitive deficit, however, has yet to be explored and could provide important insights into mechanisms and prediction of delirium. OBJECTIVE: Our goal was to determine if certain cognitive domains from the general cognitive screener, the Mini-Mental State Exam (MMSE), predict delirium after cardiac surgery. METHODS: Patients completed a preoperative MMSE prior to undergoing elective cardiac surgery. Following surgery, delirium was assessed throughout ICU stay using the Confusion Assessment Method for ICU delirium and the Richmond Agitation and Sedation Scale. RESULTS: Cardiac surgery patients who developed delirium (n = 137) had lower total MMSE scores than patients who did not develop delirium (n = 457). In particular, orientation to place, working memory, delayed recall, and language domain scores were lower. Of these, only the working memory and delayed recall domains predicted delirium in a regression model adjusting for history of chronic obstructive pulmonary disease, age, sex, and duration of cardiopulmonary bypass. For each word not recalled on the three-word delayed recall assessment, the odds of delirium increased by 50%. For each item missed on the working memory index, the odds of delirium increased by 36%. Of the patients who developed delirium, 47% had a primary impairment in memory, 21% in working memory, and 33% in both domains. The area under the receiver operating characteristics curve using only the working memory and delayed recall domains was 0.75, compared to 0.76 for total MMSE score. CONCLUSION: Delirium risk is greater for individuals with reduced MMSE scores on the delayed recall and working memory domains. Research should address why patients with memory and executive vulnerabilities are more prone to postoperative delirium than those with other cognitive limitations.

Detecting At-Risk Alzheimer's Disease Cases. - Fladby, Tormod; Pålhaugen, Lene; Selnes, Per; Waterloo, Knut; Bråthen, Geir; Hessen, Erik; Almdahl, Ina Selseth; Arntzen, Kjell-Arne; Auning, Eirik; Eliassen, Carl Fredrik; Espenes, Ragna; Grambaite, Ramune; et al. (J Alzheimers Dis, 2017)
While APOEɛ4 is the major genetic risk factor for Alzheimer's disease (AD), amyloid dysmetabolism is an initial or early event predicting clinical disease and is an important focus for secondary intervention trials. To improve identification of cases with increased AD risk, we evaluated recruitment procedures using pathological CSF concentrations of Aβ42 (pAβ) and APOEɛ4 as risk markers in a multi-center study in Norway. In total, 490 subjects aged 40-80 y were included after response to advertisements and media coverage or memory clinics referrals. Controls (n = 164) were classified as normal controls without first-degree relatives with dementia (NC), normal controls with first-degree relatives with dementia (NCFD), or controls scoring below norms on cognitive screening. Patients (n = 301) were classified as subjective cognitive decline or mild cognitive impairment. Subjects underwent a clinical and cognitive examination and MRI according to standardized protocols. Core biomarkers in CSF from 411 and APOE genotype from 445 subjects were obtained. Cases (both self-referrals (n = 180) and memory clinics referrals (n = 87)) had increased fractions of pAβ and APOEɛ4 frequency compared to NC. Also, NCFD had higher APOEɛ4 frequencies without increased fraction of pAβ compared to NC, and cases recruited from memory clinics had higher fractions of pAβ and APOEɛ4 frequency than self-referred. This study shows that memory clinic referrals are pAβ enriched, whereas self-referred and NCFD cases more frequently are pAβ negative but at risk (APOEɛ4 positive), suitable for primary intervention.

Development of a Late-Life Dementia Prediction Index with Supervised Machine Learning in the Population-Based CAIDE Study. - Pekkala, Timo; Hall, Anette; Lötjönen, Jyrki; Mattila, Jussi; Soininen, Hilkka; Ngandu, Tiia; Laatikainen, Tiina; Kivipelto, Miia; Solomon, Alina (J Alzheimers Dis, 2017)
BACKGROUND AND OBJECTIVE: This study aimed to develop a late-life dementia prediction model using a novel validated supervised machine learning method, the Disease State Index (DSI), in the Finnish population-based CAIDE study. METHODS: The CAIDE study was based on previous population-based midlife surveys. CAIDE participants were re-examined twice in late-life, and the first late-life re-examination was used as baseline for the present study. The main study population included 709 cognitively normal subjects at first re-examination who returned to the second re-examination up to 10 years later (incident dementia n = 39). An extended population (n = 1009, incident dementia 151) included non-participants/non-survivors (national registers data). DSI was used to develop a dementia index based on first re-examination assessments. Performance in predicting dementia was assessed as area under the ROC curve (AUC). RESULTS: AUCs for DSI were 0.79 and 0.75 for main and extended populations. Included predictors were cognition, vascular factors, age, subjective memory complaints, and APOE genotype. CONCLUSION: The supervised machine learning method performed well in identifying comprehensive profiles for predicting dementia development up to 10 years later. DSI could thus be useful for identifying individuals who are most at risk and may benefit from dementia prevention interventions.

Development of Nasal Lipid Nanocarriers Containing Curcumin for Brain Targeting. - Vaz, Gustavo Richter; Hädrich, Gabriela; Bidone, Juliana; Rodrigues, Jamile Lima; Falkembach, Mariana Corrêa; Putaux, Jean-Luc; Hort, Mariana Appel; Monserrat, José Maria; Varela Junior, Antônio Sergio; Teixeira, Helder Ferreira; Muccillo-Baisch, Ana Luiza; Horn, Ana Paula; et al. (J Alzheimers Dis, 2017)
BACKGROUND: Curcumin (CUR) has properties that can be useful for the treatment of Alzheimer's disease. Such properties are the inhibition of amyloid-β-protein (Aβ) aggregation, Aβ-induced inflammation, and activities of β-secretase and acetylcholinesterase. However, previous studies have revealed that CUR exhibited low bioavailability and difficulties in reaching the brain. OBJECTIVE: To overcome such drawbacks, this study aims at developing nasal lipid nanocarriers loaded with CUR to effectively target the brain. METHODS: The lipid nanocarriers (NE) were prepared using the hot solvent diffusion associated with the phase inversion temperature methods. Physico-chemical and morphological characterizations and in vitro drug release of the nanocarriers were carried out. The CUR permeation/retention was analyzed in Franz-type diffusion cell using porcine nasal mucosa. Confocal laser scan and histopathological studies were also performed. RESULTS: The results showed that the NE sizes ranged between 18 nm and 44 nm with negative zeta potential. The CUR content ranged from 0.24 to 1.50 mg/mL with an encapsulation efficiency of 99%. The profiles of CUR release indicated a biphasic kinetics. CUR-NE permeation across the porcine nasal mucosa was higher when compared to free CUR. These results have also been validated through an analysis on a confocal microscopy. In addition, no toxicity on the nasal mucosa has been observed in a histopathological analysis. CONCLUSION: These results suggest that it is possible to develop NEs with a high content of CUR and small particle size. Such an encapsulation increases the potential of CUR permeation across the porcine nasal mucosa.

The Diagnostic and Prognostic Value of Neuropsychological Assessment in Memory Clinic Patients. - Jansen, Willemijn J; Handels, Ron L H; Visser, Pieter Jelle; Aalten, Pauline; Bouwman, Femke; Claassen, Jurgen; van Domburg, Peter; Hoff, Erik; Hoogmoed, Jan; Leentjens, Albert F G; Rikkert, Marcel Olde; Oleksik, Ania M; et al. (J Alzheimers Dis, 2017)
BACKGROUND: Neuropsychological testing has long been embedded in daily clinical practice at memory clinics but the added value of a complete neuropsychological assessment (NPA) to standard clinical evaluation is unknown. OBJECTIVE: To evaluate the added diagnostic and prognostic value of NPA to clinical evaluation only in memory clinic patients. METHODS: In 221 memory clinic patients of a prospective cohort study, clinical experts diagnosed clinical syndrome (subjective cognitive impairment (SCI), mild cognitive impairment (MCI), or dementia) and etiology (Alzheimer's disease (AD) or no AD), and provided a prognosis of disease course (decline or no decline) before and after results of NPA were made available. The reference standard was a panel consensus based on all clinical information at baseline and up to 2 follow-up assessments. RESULTS: With NPA data available, clinicians changed their initial syndromal diagnosis in 22% of patients, and the etiological diagnosis as well as the prognosis in 15%. This led to an increase in correctly classified cases of 18% for syndromal diagnosis, 5% for etiological diagnosis, and 1% for prognosis. NPA data resulted in the largest improvement in patients initially classified as SCI (syndrome: 93.3% (n = 14) correctly reclassified, etiology: net reclassification improvement [NRI] = 0.61, prognosis: NRI = 0.13) or MCI (syndrome: 89.3% (n = 23) correctly reclassified, etiology: NRI = 0.17, prognosis: NRI = 0.14), while there was no improvement in patients with dementia (syndrome: 100% (n = 1) correctly reclassified, etiology: NRI = -0.05, prognosis: NRI = -0.06). Overall, inclusion of NPA in the diagnostic process increased confidence in all diagnoses with 6-7%. CONCLUSION: Administration of a complete NPA after standard clinical evaluation has added value for diagnosing cognitive syndrome and its underlying etiology in patients regarded as non-demented based on the first clinical impression.

Diagnostic Biomarkers of Alzheimer's Disease as Identified in Saliva using 1H NMR-Based Metabolomics. - Yilmaz, Ali; Geddes, Tim; Han, BeomSoo; Bahado-Singh, Ray O; Wilson, George; Imam, Khaled; Maddens, Michael; Graham, Stewart F (J Alzheimers Dis, 2017)
Using 1H NMR metabolomics, we biochemically profiled saliva samples collected from healthy-controls (n = 12), mild cognitive impairment (MCI) sufferers (n = 8), and Alzheimer's disease (AD) patients (n = 9). We accurately identified significant concentration changes in 22 metabolites in the saliva of MCI and AD patients compared to controls. This pilot study demonstrates the potential for using metabolomics and saliva for the early diagnosis of AD. Given the ease and convenience of collecting saliva, the development of accurate and sensitive salivary biomarkers would be ideal for screening those at greatest risk of developing AD.

Diagnostic Value of a Tablet-Based Drawing Task for Discrimination of Patients in the Early Course of Alzheimer's Disease from Healthy Individuals. - Müller, Stephan; Preische, Oliver; Heymann, Petra; Elbing, Ulrich; Laske, Christoph (J Alzheimers Dis, 2017)
There is a considerable delay in the diagnosis of dementia, which may reduce the effectiveness of available treatments. Thus, it is of great interest to develop fast and easy to perform, non-invasive and non-expensive diagnostic measures for the early detection of cognitive impairment and dementia. Here we investigate movement kinematics between 20 patients with early dementia due to Alzheimer's disease (eDAT), 30 patients with amnestic mild cognitive impairment (aMCI), and 20 cognitively healthy control (HC) individuals while copying a three-dimensional house using a digitizing tablet. Receiver-operating characteristic (ROC) curves and logistic regression analyzes have been conducted to explore whether alterations in movement kinematics could be used to discriminate patients with aMCI and eDAT from healthy individuals. Time-in-air (i.e., transitioning from one stroke to the next without touching the surface) differed significantly between patients with aMCI, eDAT, and HCs demonstrating an excellent sensitivity and a moderate specificity to discriminate aMCI subjects from normal elderly and an excellent sensitivity and specificity to discriminate patients affected by mild Alzheimer's disease from healthy individuals. Time-on-surface (i.e., time while stylus is touching the surface) differed only between HCs and patients with eDAT but not between HCs and patients with aMCI. Furthermore, total-time (i.e., time-in-air plus time-on-surface) did not differ between patients with aMCI and early dementia due to AD. Modern digitizing devices offer the opportunity to measure a broad range of visuoconstructive abilities that may be used as a fast and easy to perform screening instrument for the early detection of cognitive impairment and dementia in primary care.

Dietary Lycopene Supplementation Improves Cognitive Performances in Tau Transgenic Mice Expressing P301L Mutation via Inhibiting Oxidative Stress and Tau Hyperphosphorylation. - Yu, Lixia; Wang, Weiguang; Pang, Wei; Xiao, Zhonghai; Jiang, Yugang; Hong, Yan (J Alzheimers Dis, 2017)
BACKGROUND: Oxidative stress is implicated in the pathogenesis of Alzheimer's disease (AD) and other tauopathies and participates in their development by promoting hyperphosphorylation of microtubule-associated protein tau. Lycopene, as an effective antioxidant, combined with vitamin E seemed to be additive against oxidative stress. OBJECTIVE: The present study was undertaken to examine whether lycopene or lycopene/vitamin E could exert protective effects on memory deficit and oxidative stress in tau transgenic mice expressing P301L mutation. MATERIALS AND METHODS: P301L transgenic mice were assigned to three groups: P301L group (P301L), P301L+lycopene (Lyc), and P301L+lycopene/vitamin E (Lyc+VE). Age-matched C57BL/6J mice as wild type controls (Con) were used in the present study. Spatial memory was assessed by radial arm while passive memories were evaluated by step-down and step-through tests. Levels of tau phosphorylation were detected by western blot. Oxidative stress biomarkers were measured in the serum using biochemical assay kits. RESULTS: Compared with the control group, P301L mice displayed significant spatial and passive memory impairments, elevated malondialdehyde (MDA) levels and decreased glutathione peroxidase (GSH-Px) activities in serum, and increased tau phosphorylation at Thr231/Ser235, Ser262, and Ser396 in brain. Supplementations of lycopene or lycopene/vitamin E could significantly ameliorate the memory deficits, observably decreased MDA concentrations and increased GSH-Px activities, and markedly attenuated tau hyperphosphorylation at multiple AD-related sites. CONCLUSIONS: Our findings indicated that the combination of lycopene and vitamin E antioxidants acted in a synergistic fashion to bring significant effects against oxidative stress in tauopathies.

Differential Hemispheric Predilection of Microstructural White Matter and Functional Connectivity Abnormalities between Respectively Semantic and Behavioral Variant Frontotemporal Dementia. - Meijboom, Rozanna; Steketee, Rebecca M E; Ham, Leontine S; van der Lugt, Aad; van Swieten, John C; Smits, Marion (J Alzheimers Dis, 2017)
Semantic dementia (SD) and behavioral variant frontotemporal dementia (bvFTD), subtypes of frontotemporal dementia, are characterized by distinct clinical symptoms and neuroimaging features, with predominant left temporal grey matter (GM) atrophy in SD and bilateral or right frontal GM atrophy in bvFTD. Such differential hemispheric predilection may also be reflected by other neuroimaging features, such as brain connectivity. This study investigated white matter (WM) microstructure and functional connectivity differences between SD and bvFTD, focusing on the hemispheric predilection of these differences. Eight SD and 12 bvFTD patients, and 17 controls underwent diffusion tensor imaging and resting state functional MRI at 3T. Whole-brain WM microstructure was assessed to determine distinct WM tracts affected in SD and bvFTD. For these tracts, diffusivity measures and lateralization indices were calculated. Functional connectivity was established for GM regions affected in early stage SD or bvFTD. Results of a direct comparison between SD and bvFTD are reported. Whole-brain WM microstructure abnormalities were more pronounced in the left hemisphere in SD and bilaterally- with a slight predilection for the right- in bvFTD. Lateralization of tract-specific abnormalities was seen in SD only, toward the left hemisphere. Functional connectivity of disease-specific regions was mainly decreased bilaterally in SD and in the right hemisphere in bvFTD. SD and bvFTD show WM microstructure and functional connectivity abnormalities in different regions, that are respectively more pronounced in the left hemisphere in SD and in the right hemisphere in bvFTD. This indicates differential hemispheric predilection of brain connectivity abnormalities between SD and bvFTD.

Dissociable Effects of Aging and Mild Cognitive Impairment on Bottom-Up Audiovisual Integration. - Festa, Elena K; Katz, Andrew P; Ott, Brian R; Tremont, Geoffrey; Heindel, William C (J Alzheimers Dis, 2017)
Effective audiovisual sensory integration involves dynamic changes in functional connectivity between superior temporal sulcus and primary sensory areas. This study examined whether disrupted connectivity in early Alzheimer's disease (AD) produces impaired audiovisual integration under conditions requiring greater corticocortical interactions. Audiovisual speech integration was examined in healthy young adult controls (YC), healthy elderly controls (EC), and patients with amnestic mild cognitive impairment (MCI) using McGurk-type stimuli (providing either congruent or incongruent audiovisual speech information) under conditions differing in the strength of bottom-up support and the degree of top-down lexical asymmetry. All groups accurately identified auditory speech under congruent audiovisual conditions, and displayed high levels of visual bias under strong bottom-up incongruent conditions. Under weak bottom-up incongruent conditions, however, EC and amnestic MCI groups displayed opposite patterns of performance, with enhanced visual bias in the EC group and reduced visual bias in the MCI group relative to the YC group. Moreover, there was no overlap between the EC and MCI groups in individual visual bias scores reflecting the change in audiovisual integration from the strong to the weak stimulus conditions. Top-down lexicality influences on visual biasing were observed only in the MCI patients under weaker bottom-up conditions. Results support a deficit in bottom-up audiovisual integration in early AD attributable to disruptions in corticocortical connectivity. Given that this deficit is not simply an exacerbation of changes associated with healthy aging, tests of audiovisual speech integration may serve as sensitive and specific markers of the earliest cognitive change associated with AD.

Does Functional Connectivity Provide a Marker for Cognitive Rehabilitation Effects in Alzheimer's Disease? An Interventional Study. - Ochmann, Sina; Dyrba, Martin; Grothe, Michel J; Kasper, Elisabeth; Webel, Steffi; Hauenstein, Karlheinz; Teipel, Stefan J (J Alzheimers Dis, 2017)
BACKGROUND: Cognitive rehabilitation (CR) is a cognitive intervention for patients with Alzheimer's disease (AD) that aims to maintain everyday competences. The analysis of functional connectivity (FC) in resting-state functional MRI has been used to investigate the effects of cognitive interventions. OBJECTIVES: We evaluated the effect of CR on the default mode network FC in a group of patients with mild AD, compared to an active control group. METHODS: We performed a three-month interventional study including 16 patients with a diagnosis of AD. The intervention group (IG) consisted of eight patients, performing twelve sessions of CR. The active control group (CG) performed a standardized cognitive training. We used a seed region placed in the posterior cingulate cortex (PCC) for FC analysis, comparing scans acquired before and after the intervention. Effects were thresholded at a significance of p < 0.001 (uncorrected) and a minimal cluster size of 50 voxels. RESULTS: The interaction of group by time showed a higher increase of PCC connectivity in IG compared to CG in the bilateral cerebellar cortex. CG revealed widespread, smaller clusters of higher FC increase compared with IG. Across all participants, an increase in quality of life was associated with connectivity increase over time in the bilateral precuneus. CONCLUSIONS: CR showed an effect on the FC of the DMN in the IG. These effects need further study in larger samples to confirm if FC analysis may suit as a surrogate marker for the effect of cognitive interventions in AD.

Down Syndrome, Partial Trisomy 21, and Absence of Alzheimer's Disease: The Role of APP. - Doran, Eric; Keator, David; Head, Elizabeth; Phelan, Michael J; Kim, Ron; Totoiu, Minodora; Barrio, Jorge R; Small, Gary W; Potkin, Steven G; Lott, Ira T (J Alzheimers Dis, 2017)
Overexpression of the amyloid precursor protein (APP) gene on chromosome 21 in Down syndrome (DS) has been linked to increased brain amyloid levels and early-onset Alzheimer's disease (AD). An elderly man with phenotypic DS and partial trisomy of chromosome 21 (PT21) lacked triplication of APP affording an opportunity to study the role of this gene in the pathogenesis of dementia. Multidisciplinary studies between ages 66-72 years comprised neuropsychological testing, independent neurological exams, amyloid PET imaging with 11C-Pittsburgh compound-B (PiB), plasma amyloid-β (Aβ) measurements, and a brain autopsy examination. The clinical phenotype was typical for DS and his intellectual disability was mild in severity. His serial neuropsychological test scores showed less than a 3% decline as compared to high functioning individuals with DS who developed dementia wherein the scores declined 17-28% per year. No dementia was detected on neurological examinations. On both PiB-PET scans, the patient with PT21 had lower PiB standard uptake values than controls with typical DS or sporadic AD. Plasma Aβ42 was lower than values for demented or non-demented adults with DS. Neuropathological findings showed only a single neuritic plaque and neurofibrillary degeneration consistent with normal aging but not AD. Taken together the findings in this rare patient with PT21 confirm the obligatory role of APP in the clinical, biochemical, and neuropathological findings of AD in DS.

The Effect of Escitalopram on Mood and Cognition in Depressive Alzheimer's Disease Subjects. - An, Hoyoung; Choi, Booyeol; Park, Kun-Woo; Kim, Do-Hoon; Yang, Dong-Won; Hong, Chang Hyung; Kim, Seong Yoon; Han, Seol-Heui (J Alzheimers Dis, 2017)
BACKGROUND: Effective treatments to alleviate depression in Alzheimer's disease (AD) have been scarce. OBJECTIVE: To investigate the efficacy and tolerability of escitalopram in the treatment of depression in AD. METHODS: In this 12-week randomized, double-blind, placebo-controlled trial with open-label, 12-week extension, AD subjects over 50 years of age, with depression defined by Olin's provisional diagnostic criteria, were enrolled. The Cornell Scale for Depression in Dementia (CSDD), and other measures of depression and cognition were repeated. RESULTS: 91 subjects were screened, and 84 were randomized into either the study group or placebo group (n = 42 for both groups). Twenty-four subjects (29%) were unable to finish the study, yielding a per protocol population of 60 subjects (study group: n = 27; placebo group: n = 33). At week 12, differences in measures of depression and cognition between the two groups were not statistically significant. However, exploratory analysis suggested that further research on a subset of subjects with 'definite major depression' (baseline CSDD score ≥18) is needed. The number of treatment-related adverse-events (AE) did not differ between groups (p = 0.83) and no serious treatment-related AE were observed. CONCLUSION: The use of escitalopram was well tolerated in depressive dementia patients. Future studies focusing on subjects with more severe levels of depression, and with more statistical power, will be needed.

Effect of Spinal Manometers on Cerebrospinal Fluid Amyloid-β Concentration. - Toombs, Jamie; Foiani, Martha S; Paterson, Ross W; Heslegrave, Amanda; Wray, Selina; Schott, Jonathan M; Fox, Nick C; Lunn, Michael P; Blennow, Kaj; Zetterberg, Henrik (J Alzheimers Dis, 2017)
The effect of spinal manometers on cerebrospinal fluid (CSF) amyloid-β (Aβ) concentration was investigated. Pooled human CSF samples were divided in two, one half passed through a manometer into a collection tube, the other transferred directly to a collection tube. CSF was analyzed for Aβ38/40/42 using an electrochemiluminescence immunoassay. Relative to control, use of a manometer decreased Aβ38/40/42 concentration by 5.6% (±1.5SE), 4.4% (±1.7SE), and 4.3% (±2.4SE), respectively. The ratios of Aβ42 :40, Aβ42 :38, and Aβ40 :38 were not affected by manometer treatment. Factors which artificially lower CSF Aβ concentrations are relevant to clinical diagnosis for AD and study design.

Effect Size Analyses of Souvenaid in Patients with Alzheimer's Disease. - Cummings, Jeffrey; Scheltens, Philip; McKeith, Ian; Blesa, Rafael; Harrison, John E; Bertolucci, Paulo H F; Rockwood, Kenneth; Wilkinson, David; Wijker, Wouter; Bennett, David A; Shah, Raj C (J Alzheimers Dis, 2017)
BACKGROUND: Souvenaid® (uridine monophosphate, docosahexaenoic acid, eicosapentaenoic acid, choline, phospholipids, folic acid, vitamins B12, B6, C, and E, and selenium), was developed to support the formation and function of neuronal membranes. OBJECTIVE: To determine effect sizes observed in clinical trials of Souvenaid and to calculate the number needed to treat to show benefit or harm. METHODS: Data from all three reported randomized controlled trials of Souvenaid in Alzheimer's disease (AD) dementia (Souvenir I, Souvenir II, and S-Connect) and an open-label extension study were included in analyses of effect size for cognitive, functional, and behavioral outcomes. Effect size was determined by calculating Cohen's d statistic (or Cramér's V method for nominal data), number needed to treat and number needed to harm. Statistical calculations were performed for the intent-to-treat populations. RESULTS: In patients with mild AD, effect sizes were 0.21 (95% confidence intervals: -0.06, 0.49) for the primary outcome in Souvenir II (neuropsychological test battery memory z-score) and 0.20 (0.10, 0.34) for the co-primary outcome of Souvenir I (Wechsler memory scale delayed recall). No effect was shown on cognition in patients with mild-to-moderate AD (S-Connect). The number needed to treat (6 and 21 for Souvenir I and II, respectively) and high number needed to harm values indicate a favorable harm:benefit ratio for Souvenaid versus control in patients with mild AD. CONCLUSIONS: The favorable safety profile and impact on outcome measures converge to corroborate the putative mode of action and demonstrate that Souvenaid can achieve clinically detectable effects in patients with early AD.

Effects of a DJ-1-Binding Compound on Spatial Learning and Memory Impairment in a Mouse Model of Alzheimer's Disease. - Kitamura, Yoshihisa; Inden, Masatoshi; Kimoto, Yasuto; Takata, Kazuyuki; Yanagisawa, Daijiro; Hijioka, Masanori; Ashihara, Eishi; Tooyama, Ikuo; Shimohama, Shun; Ariga, Hiroyoshi (J Alzheimers Dis, 2017)
Previously, DJ-1 modulator UCP0054278/comp-B was identified by virtual screening, where comp-B interacts with DJ-1 to produce antioxidant and neuroprotective responses in Parkinson's disease models. However, the effect of comp-B in an in vivo Alzheimer's disease (AD) model is yet undetermined. Thus, we examined the effect of comp-B on spatial learning, memory, and amyloid-β (Aβ) clearance in a transgenic mouse model of AD. We found that comp-B resolved the cognitive deficits, reduced insoluble Aβ42 levels, and prevented the degeneration of synaptic functions, thereby suggesting that comp-B may become a major compound for AD treatment.

Effects of Alzheimer's Disease-Associated Risk Loci on Amyloid-β Accumulation in the Brain of Idiopathic Normal Pressure Hydrocephalus Patients. - Laiterä, Tiina; Paananen, Jussi; Helisalmi, Seppo; Sarajärvi, Timo; Huovinen, Joel; Laitinen, Marjo; Rauramaa, Tuomas; Alafuzoff, Irina; Remes, Anne M; Soininen, Hilkka; Haapasalo, Annakaisa; Jääskeläinen, Juha E; et al. (J Alzheimers Dis, 2017)
BACKGROUND: Idiopathic normal pressure hydrocephalus (iNPH) is a dementing condition featuring characteristic symptoms, ventriculomegaly, and normal or slightly elevated cerebrospinal fluid pressure. In Alzheimer's disease (AD) patients, diffuse aggregates of amyloid-β (Aβ) and neurofibrillary hyperphosphorylated tau are detected in the neocortex of the brain, while similar accumulation of Aβ is also detected in iNPH. Recent genome-wide association studies have identified several novel risk loci for AD, potentially affecting Aβ-related cellular processes. Apart from the apolipoprotein E ɛ4 allele (APOE4), the risk effect of single loci is low, emphasizing the importance of the polygenic risk score approach when assessing the combined effects. OBJECTIVE: To study the effects of AD-associated individual and polygenic risk score of single nucleotide polymorphisms (SNPs) on the accumulation of Aβ in the brain samples of iNPH patients. METHODS: A sample set of frontal cortex biopsies from 188 iNPH patients were divided into two groups according to the Aβ pathology. After the genotyping of the AD-associated risk loci, polygenic risk score was calculated for each iNPH patient and subsequently analyzed in relation to Aβ deposition. RESULTS: Apart from the APOE4, none of the SNPs revealed a statistically significant effect on the accumulation of Aβ in iNPH. Also, the non-APOE4 polygenic risk score did not associate with Aβ deposition. CONCLUSION: Novel AD-associated risk genes have no significant effect on Aβ accumulation in the brain of iNPH patients. However, APOE4 affects the Aβ deposition in the brain of iNPH and AD patients in a similar manner.

Effects of Exercise on Cognitive Function in Older People with Dementia: A Randomized Controlled Trial. - Toots, Annika; Littbrand, Håkan; Boström, Gustaf; Hörnsten, Carl; Holmberg, Henrik; Lundin-Olsson, Lillemor; Lindelöf, Nina; Nordström, Peter; Gustafson, Yngve; Rosendahl, Erik (J Alzheimers Dis, 2017)
BACKGROUND: Although physical exercise has been suggested to influence cognitive function, previous exercise studies show inconsistent results in people with dementia. OBJECTIVES: To investigate effects of exercise on cognitive function in people with dementia. METHOD: The Umeå Dementia and Exercise (UMDEX) study, a cluster-randomized controlled trial, was set in 16 nursing homes in Umeå, Sweden. One hundred-and-forty-one women and 45 men with dementia; mean age of 85 y and mean Mini-Mental State Examination (MMSE) score of 15, were randomized to a High-Intensity Functional Exercise program or a seated attention control activity. Blinded assessors measured global cognitive function using the MMSE and the Alzheimer's disease Assessment Scale - Cognitive subscale (ADAS-Cog), and executive function using Verbal fluency (VF) at baseline and 4 months (directly after intervention completion), and MMSE and VF at 7 months. RESULTS: Linear mixed models showed no between-group effects in mean difference from baseline (95% confidence intervals, CI) at 4 months in MMSE (-0.27; 95% CI -1.4 to 0.87, p = 0.644), ADAS-Cog (-1.04, 95% CI -4 to 1.92, p = 0.491), or VF (-0.53, 95% CI -1.42 to 0.35, p = 0.241) or at 7 months in MMSE (-1.15, 95% CI -2.32 to 0.03, p = 0.056) or VF (-0.18, 95% CI -1.09 to 0.74, p = 0.707). CONCLUSION: A 4-month, high-intensity functional exercise program had no superior effects on global cognition or executive function in people with dementia living in nursing homes when compared with an attention control activity.

Effects of Multiple Genetic Loci on Age at Onset in Frontotemporal Dementia. - Ferrari, Raffaele; Grassi, Mario; Graziano, Francesca; Palluzzi, Fernando; Archetti, Silvana; Bonomi, Elisa; Bruni, Amalia C; Maletta, Raffaele G; Bernardi, Livia; Cupidi, Chiara; Colao, Rosanna; Rainero, Innocenzo; et al. (J Alzheimers Dis, 2017)
In frontotemporal dementia (FTD), age at disease onset (AAO) is unpredictable in both early and late-onset cases; AAO variability is found even in autosomal dominant FTD. The present study was aimed at identifying genetic modifiers modulating AAO in a large cohort of Italian FTD patients. We conducted an association analysis on 411 FTD patients, belonging to 7 Italian Centers, and for whom AAO was available. Population structure was evaluated by principal component analysis to infer continuous axes of genetic variation, and single linear regression models were applied. A genetic score (GS) was calculated on the basis of suggestive single nucleotide polymorphisms (SNPs) found by association analyses. GS showed genome-wide significant slope decrease by -3.86 (95% CI: -4.64 to -3.07, p < 2×10-16) per standard deviation of the GS for 6 SNPs mapping to genes involved in neuronal development and signaling, axonal myelinization, and glutamatergic/GABA neurotransmission. An increase of the GS was associated with a decrease of the AAO. Our data indicate that there is indeed a genetic component that underpins and modulates up to 14.5% of variability of AAO in Italian FTD. Future studies on genetic modifiers in FTD are warranted.

Effects of Regular and Long-Acting Insulin on Cognition and Alzheimer's Disease Biomarkers: A Pilot Clinical Trial. - Craft, Suzanne; Claxton, Amy; Baker, Laura D; Hanson, Angela J; Cholerton, Brenna; Trittschuh, Emily H; Dahl, Deborah; Caulder, Erin; Neth, Bryan; Montine, Thomas J; Jung, Youngkyoo; Maldjian, Joseph; et al. (J Alzheimers Dis, 2017)
BACKGROUND: Long acting insulin detemir administered intranasally for three weeks enhanced memory for adults with Alzheimer's disease dementia (AD) or amnestic mild cognitive impairment (MCI). The investigation of longer-term administration is necessary to determine whether benefits persist, whether they are similar to benefits provided by regular insulin, and whether either form of insulin therapy affects AD biomarkers. OBJECTIVE: The present study aimed to determine whether four months of treatment with intranasal insulin detemir or regular insulin improves cognition, daily functioning, and AD biomarkers for adults with MCI or AD. METHODS: This randomized, double-blind, placebo-controlled trial included an intent-to-treat sample consisting of 36 adults diagnosed with MCI or mild to moderate AD. Participants received placebo (n = 12), 40 IU of insulin detemir (n = 12), or 40 IU of regular insulin (n = 12) daily for four months, administered with a nasal delivery device. A cognitive battery was administered at baseline and after two and four months of treatment. MRI was administered for all participants and lumbar puncture for a subset (n = 20) at baseline and four months. The primary outcome was change from baseline to four months on a memory composite (sum of Z scores for delayed list and story recall). Secondary outcomes included: global cognition (Alzheimer's Disease Assessment Scale-Cognition), daily functioning (Dementia Severity Rating Scale), MRI volume changes in AD-related regions of interest, and cerebrospinal fluid AD markers. RESULTS: The regular insulin treated group had better memory after two and four months compared with placebo (p < 0.03). No significant effects were observed for the detemir-assigned group compared with the placebo group, or for daily functioning for either group. Regular insulin treatment was associated with preserved volume on MRI. Regular insulin treatment was also associated with reduction in the tau-P181/Aβ42 ratio. CONCLUSION: Future research is warranted to examine the mechanistic basis of treatment differences, and to further assess the efficacy and safety of intranasal insulin.

Effects of Short-Term Exercise Interventions on Behavioral and Psychological Symptoms in Patients with Dementia: A Systematic Review. - Fleiner, Tim; Leucht, Stefan; Förstl, Hans; Zijlstra, Wiebren; Haussermann, Peter (J Alzheimers Dis, 2017)
Observational and interventional studies indicate a direct link between the patients' physical activity and the extent of behavioral and psychological symptoms of dementia (BPSD). At present, there are no evidence-based recommendations for physical exercise in the acute dementia care settings. Hence, this systematic review investigates the effects of short-term exercise trials on BPSD. Trials with a length up to three months investigating the effects of structured exercise interventions on BPSD in acute dementia care settings were included. Five trials, referring to a total of N = 206 patients, met the inclusion criteria. The trial durations ranged from three up to twelve weeks. All trials conducted three sessions per week of 30 to 45 minutes. Three trials reported significant reductions of BPSD and differences in comparison to the pre-test and control groups. Out of the three trials investigating the effects of exercise interventions on depressive symptoms, one reported significant reduction and two reported no differences in pre-post analysis. Exercise represents a potentially worthwhile approach for the treatment of patients suffering from BPSD. Given the scarcity of available studies, more randomized controlled short-term exercise trials in acute dementia care settings are needed to define appropriate exercise recommendations for clinicians treating these patients.

Efficacy and Safety of Plasma Exchange with 5% Albumin to Modify Cerebrospinal Fluid and Plasma Amyloid-β Concentrations and Cognition Outcomes in Alzheimer's Disease Patients: A Multicenter, Randomized, Controlled Clinical Trial. - Boada, Merce; Anaya, Fernando; Ortiz, Pilar; Olazarán, Javier; Shua-Haim, Joshua R; Obisesan, Thomas O; Hernandez, Isabel; Muñoz, Joan; Buendia, Mar; Alegret, Montserrat; Lafuente, Asunción; Tárraga, Lluís; et al. (J Alzheimers Dis, 2017)
BACKGROUND: Studies conducted in animal models and humans suggest the presence of a dynamic equilibrium of amyloid-β (Aβ) peptide between cerebrospinal fluid (CSF) and plasma compartments. OBJECTIVE: To determine whether plasma exchange (PE) with albumin replacement was able to modify Aβ concentrations in CSF and plasma as well as to improve cognition in patients with mild-moderate Alzheimer's disease (AD). METHODS: In a multicenter, randomized, patient- and rater-blind, controlled, parallel-group, phase II study, 42 AD patients were assigned (1 : 1) to PE treatment or control (sham) groups. Treated patients received a maximum of 18 PE with 5% albumin (Albutein®, Grifols) with three different schedules: two PE/weekly (three weeks), one PE/weekly (six weeks), and one PE/bi- weekly (12 weeks), plus a six-month follow-up period. Plasma and CSF Aβ1-40 and Aβ1-42 levels, as well as cognitive, functional, and behavioral measures were determined. RESULTS: CSF Aβ1-42 levels after the last PE compared to baseline were marginally higher in PE-treated group versus controls (adjusted means of variation: 75.3 versus -45.5 pg/mL; 95% CI: -19.8, 170.5 versus 135.1, 44.2; p = 0.072). Plasma Aβ1-42 levels were lower in the PE-treated group after each treatment period (p < 0.05). Plasma Aβ1-40 levels showed a saw-tooth pattern variation associated with PE. PE-treated patients scored better in the Boston Naming Test and Semantic Verbal Fluency (p < 0.05) throughout the study. Neuropsychiatric Inventory scores were higher in controls during the PE phase (p < 0.05). CONCLUSION: PE with human albumin modified CSF and plasma Aβ1-42 levels. Patients treated with PE showed improvement in memory and language functions, which persisted after PE was discontinued.

Efficacy of Antidepressants for Depression in Alzheimer's Disease: Systematic Review and Meta-Analysis. - Orgeta, Vasiliki; Tabet, Naji; Nilforooshan, Ramin; Howard, Robert (J Alzheimers Dis, 2017)
BACKGROUND: Depression is common in people with Alzheimer's disease (AD) affecting overall outcomes and decreasing quality of life. Although depression in AD is primarily treated with antidepressants, there are few randomized controlled trials (RCTs) assessing efficacy and results have been conflicting. OBJECTIVES: To systematically review evidence on efficacy of antidepressant treatments for depression in AD. METHODS: Systematic review and meta-analysis of double blind RCTs comparing antidepressants versus placebo for depression in AD. We searched MEDLINE, CINAHL, EMBASE, PsycINFO, the Cochrane Controlled Trials Register and on line national and international registers. Primary outcomes were treatment response and depressive symptoms. Secondary outcomes were cognition, acceptability, and tolerability. Risk of bias was also assessed. RESULTS: Seven studies met inclusion criteria. Three compared sertraline with placebo; one compared both sertraline and mirtazapine to placebo; imipramine, fluoxetine, and clomipramine were evaluated in one study each. In terms of response to treatment (6 studies, 297 patients treated with antidepressants and 223 with placebo), no statistically significant difference between antidepressants and placebo was found (odds ratio (OR) 1.95, 95% CI 0.97-3.92). We found no significant drug-placebo difference for depressive symptoms (5 studies, 311 patients, SMD -0.13; 95% CI -0.49 to 0.24). Overall quality of the evidence was moderate because of methodological limitations in studies and the small number of trials. CONCLUSION: Despite the importance of depression in people with AD, few RCTs are available on efficacy of antidepressants, limiting clear conclusions of their potential role. There is a need for further high quality RCTs.

Egocentric versus Allocentric Spatial Memory in Behavioral Variant Frontotemporal Dementia and Alzheimer's Disease. - Tu, Sicong; Spiers, Hugo J; Hodges, John R; Piguet, Olivier; Hornberger, Michael (J Alzheimers Dis, 2017)
BACKGROUND: Diagnosis of behavioral variant frontotemporal dementia (bvFTD) can be challenging, in particular when patients present with significant memory problems, which can increase the chance of a misdiagnosis of Alzheimer's disease (AD). Growing evidence suggests spatial orientation is a reliable cognitive marker able to differentiate these two clinical syndromes. OBJECTIVE: Assess the integrity of egocentric and allocentric heading orientation and memory in bvFTD and AD, and their clinical implications. METHOD: A cohort of 22 patients with dementia (11 bvFTD; 11 AD) and 14 healthy controls were assessed on the virtual supermarket task of spatial orientation and a battery of standardized neuropsychological measures of visual and verbal memory performance. RESULTS: Judgements of egocentric and allocentric heading direction were differentially impaired in bvFTD and AD, with AD performing significantly worse on egocentric heading judgements than bvFTD. Both patient cohorts, however, showed similar degree of impaired allocentric spatial representation, and associated hippocampal pathology. CONCLUSIONS: The findings suggest egocentric heading judgements offer a more sensitive discriminant of bvFTD and AD than allocentric map-based measures of spatial memory.

Factors Underpinning Caregiver Burden in Frontotemporal Dementia Differ in Spouses and their Children. - Kaizik, Cassandra; Caga, Jashelle; Camino, Julieta; O'Connor, Claire M; McKinnon, Colleen; Oyebode, Jan R; Piguet, Olivier; Hodges, John R; Mioshi, Eneida (J Alzheimers Dis, 2017)
The objectives of this observational study were to (1) compare spousal and child caregiver burden; (2) compare co-resident and live-out child caregiver burden; and (3) investigate factors influencing spousal and child caregiver burden. Data was collected from 90 caregivers of people with frontotemporal degeneration (FTD) recruited from the Frontotemporal Dementia Research Group (Frontier) at Neuroscience Research, Australia. Of this caregiver group, 43 were spousal caregivers and 47 were child caregivers. Caregiver burden and emotional state were evaluated using the short Zarit Burden Interview and the short version of the Depression, Anxiety and Stress Scale-21. The Social Network Index was applied to ascertain the social network of the caregiver, while the Intimate Bond Measure was used to evaluate the current quality of the relationship between the caregiver and the person with dementia. The Frontotemporal Dementia Rating Scale was used to assess severity of dementia. Spousal and child caregivers experienced similar levels of burden, depression, anxiety, and stress, regardless of disease severity. Co-resident child caregivers had smaller social networks and greater burden than live-out caregivers. Dementia severity was key in spousal caregiver burden, whereas caregiver depression was most important in child caregiver burden. Child and spousal caregivers of individuals with FTD share similar levels of burden, influenced by different factors. Future interventions need to account for these differences.

Family History of Alzheimer's Disease is Associated with Impaired Perceptual Discrimination of Novel Objects. - Mason, Emily J; Hussey, Erin P; Molitor, Robert J; Ko, Philip C; Donahue, Manus J; Ally, Brandon A (J Alzheimers Dis, 2017)
Early detection may be the key to developing therapies that will combat Alzheimer's disease (AD). It has been consistently demonstrated that one of the main pathologies of AD, tau, is present in the brain decades before a clinical diagnosis. Tau pathology follows a stereotypical route through the medial temporal lobe beginning in the entorhinal and perirhinal cortices. If early pathology leads to very subtle changes in behavior, it may be possible to detect these changes in subjects years before a clinical diagnosis can currently be made. We aimed to discover if cognitively normal middle-aged adults (40-60 years old) at increased risk for AD due to family history would have impaired performance on a cognitive task known to challenge the perirhinal cortex. Using an oddity detection task, we found that subjects with a family history of AD had lowered accuracy without demonstrating differences in rate of acquisition. There were no differences between subjects' medial temporal lobe volume or cortical thickness, indicating that the changes in behavior were not due to significant atrophy. These results demonstrate that subtle changes in perceptual processing are detectable years before a typical diagnosis even when there are no differences detectable in structural imaging data. Anatomically-targeted cognitive testing may be useful in identifying subjects in the earliest stages of AD.
Keywords: Adult; Alzheimer Disease; Cerebral Cortex; Discrimination (Psychology); Family Health; Female; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Neuropsychological Tests; Perceptual Disorders; Photic Stimulation; Recognition (Psychology); Signal Detection, Psychological

Frequency-Dependent Changes in the Amplitude of Low-Frequency Fluctuations in Mild Cognitive Impairment with Mild Depression. - Li, Yuxia; Jing, Bin; Liu, Han; Li, Yifan; Gao, Xuan; Li, Yongqiu; Mu, Bin; Yu, Haikuo; Cheng, Jinbo; Barker, Peter B; Wang, Hongxing; Han, Ying (J Alzheimers Dis, 2017)
BACKGROUND: Depression is a potential marker of preclinical Alzheimer's disease (AD). However, little is known about the abnormal characteristics revealed by resting-state functional magnetic resonance imaging (rs-fMRI) in mild cognitive impairment (MCI) subjects with depressive symptoms (MCI-d). OBJECTIVE: The study was to examine whether abnormalities in amplitudes of low-frequency oscillation occurred in MCI-d and tried to find the possible spectrum showed higher recognition ability to the diagnosis by utilizing functional MRI (fMRI). METHODS: The amplitude of low-frequency fluctuation (ALFF) and fractional ALFF (fALFF) within full frequency (0.01-0.1 Hz), slow-5 (0.01-0.027 Hz), and slow-4 (0.027-0.073 Hz) were computed using resting-state fMRI data of 27 MCI without depressive symptoms, 19 MCI-d, and 32 well-matched healthy controls (HC). Analysis of covariance was performed on ALFF and fALFF among MCI, MCI-d, and HC groups. RESULTS: Several brain regions showed significant differences in ALFF and fALFF within full frequency, slow-5, and slow-4 bands among three groups. Importantly, receiver operating characteristic analysis revealed that the ALFF values in the full frequency band in the left parahippocampal gyrus and the left precuneus, Slow 5 value in ALFF in the left inferior frontal gyrus, and Slow 4 value in ALFF in the left precuneus could effectively differentiate MCI-d from MCI patients. CONCLUSION: In this study, we found that several changes in special brain regions are associated with MCI and MCI-d patients. And the differences depend on the studied frequency bands of rs-fMRI data. The affective network and the default-mode network might be damaged simultaneously in MCI-d patients.

Fully Automatic MRI-Based Hippocampus Volumetry Using FSL-FIRST: Intra-Scanner Test-Retest Stability, Inter-Field Strength Variability, and Performance as Enrichment Biomarker for Clinical Trials Using Prodromal Target Populations at Risk for Alzheimer's - Cavedo, Enrica; Suppa, Per; Lange, Catharina; Opfer, Roland; Lista, Simone; Galluzzi, Samantha; Schwarz, Adam J; Spies, Lothar; Buchert, Ralph; Hampel, Harald (J Alzheimers Dis, 2017)
BACKGROUND: MRI-based hippocampus volume is a core clinical biomarker for identification of Alzheimer's disease (AD). OBJECTIVE: To assess robustness of automatic hippocampus volumetry with the freely available FSL-FIRST software with respect to short-term repeat and across field strength imaging. FSL-FIRST hippocampus volume (FIRST-HV) was also evaluated as enrichment biomarker for mild cognitive impairment (MCI) trials. METHODS: Robustness of FIRST-HV was assessed in 51 healthy controls (HC), 74 MCI subjects, and 28 patients with AD dementia from ADNI1, each with two pairs of back-to-back scans, one at 1.5T one at 3T. Enrichment performance was tested in a second sample of 287 ADNI MCI subjects. RESULTS: FSL-FIRST worked properly in all four scans in 147 out of 153 subjects of the first sample (49 HC, 72 MCI, 26 AD). In these subjects, FIRST-HV did not differ between the first and the second scan within an imaging session, neither at 1.5T nor at 3T (p≥0.302). FIRST-HV was on average 0.78% larger at 3T compared to 1.5T (p = 0.012). The variance of the FIRST-HV difference was larger in the inter-field strength setting than in the intra-scanner settings (p < 0.0005). Computer simulations suggested that the additional variability encountered in the inter-field strength scenario does not cause a relevant degradation of FIRST-HV's prognostic performance in MCI. FIRST-HV based enrichment resulted in considerably increased effect size of the 2-years change of cognitive measures. CONCLUSION: The impact of intra-scanner test-retest and inter-field strength variability of FIRST-HV on clinical tasks is negligible. In addition, FIRST-HV is useful for enrichment in clinical MCI trials.

Functional Connectivity in the Default Mode Network is Reduced in Association with Nocturnal Awakening in Mild Cognitive Impairment. - McKinnon, Andrew C; Duffy, Shantel L; Cross, Nathan E; Terpening, Zoe; Grunstein, Ron R; Lagopoulos, Jim; Batchelor, Jennifer; Hickie, Ian B; Lewis, Simon J G; Shine, James M; Naismith, Sharon L (J Alzheimers Dis, 2017)
BACKGROUND: Sleep disturbance is prevalent in MCI, and is a risk factor for cognitive deterioration. OBJECTIVE: To identify functional connectivity deficits in the default mode network (DMN) in patients with mild cognitive impairment (MCI) and sleep disturbance, relative to MCIs with intact sleep. METHODS: Participants comprised 47 adults aged 55 years and over, recruited from the Healthy Brain Ageing Clinic at the Brain and Mind Centre, Sydney, Australia. This sample contained 15 controls and 32 participants meeting criteria for MCI. Participants underwent resting-state fMRI and actigraphy, along with comprehensive neuropsychological, medical and psychiatric assessment. MCIs were split into two groups according to average wake after sleep onset (WASO) per night. WASO equal to or greater than 1 standard deviation (SD) above the control mean was deemed to reflect disturbed sleep. There were 11 patients in the MCI sleep-disturbed group, and 21 in the MCI sleep-intact group. RESULTS: Relative to controls, MCIs demonstrated significant connectivity reductions between parietal and temporoparietal regions, and between temporal regions. Relative to MCIs with intact sleep, MCIs with sleep disturbance demonstrated reductions in functional connectivity between temporal and parietal regions, and between temporal and temporoparietal regions. CONCLUSIONS: MCIs with nocturnal awakenings demonstrate reductions in DMN connectivity. These reductions comprise brain regions that are crucially involved in sleep and memory processes. These results strengthen our previous findings, which found reduced connectivity in MCIs with self-reported sleep disturbances. Future studies may build on these findings through incorporating complementary neuroimaging techniques and experimental manipulations of sleep.

Galantamine Response Associates with Agitation and the Prefrontal Cortex in Patients with Alzheimer's Disease. - Nakayama, Sachiko; Suda, Akimitsu; Nakanishi, Atsushi; Motoi, Yumiko; Hattori, Nobutaka (J Alzheimers Dis, 2017)
Behavioral and psychological symptoms of dementia (BPSD) occur in up to 80% of AD patients and represent one of the largest factors contributing to caregiver burden. To analyze the effect of galantamine on BPSD and caregiver burden, we treated a total of 50 patients with mild AD for 12 weeks and evaluated them using the Neuropsychiatric Inventory (NPI) and Japanese version of the Zarit Caregiver Burden Interview (ZBI). We also performed regional cerebral blood flow single photon emission computed tomography (rCBF SPECT) at baseline using three-dimensional sterotatic surface projections. Total NPI and ZBI scores did not significantly change after 12-week galantamine treatment. To identify the characteristics of patients who showed improvement after galantamine treatment, we divided patients into two groups, those with and those without sub-items on the NPI. Patients with aggression showed improvement in ZBI scores (p < 0.05). A comparison of rCBF SPECT between these two groups indicated that patients with aggression exhibited increased rCBF in the right prefrontal cortex compared with those without aggression. In a patient with aggression, 20-month treatment with galantamine inhibited increases in the rCBF area in the right prefrontal lobe. These results suggest that galantamine response may be related to aggression and dysfunction of the prefrontal cortex.

Gender-Specific Degeneration of Dementia-Related Subcortical Structures Throughout the Lifespan. - Nemeth, Viola Luca; Must, Anita; Horvath, Szatmar; Király, Andras; Kincses, Zsigmond Tamas; Vecsei, Laszlo (J Alzheimers Dis, 2017)
Age-related changes in brain structure are a question of interest to a broad field of research. Structural decline has been consistently, but not unambiguously, linked to functional consequences, including cognitive impairment and dementia. One of the areas considered of crucial importance throughout this process is the medial temporal lobe, and primarily the hippocampal region. Gender also has a considerable effect on volume deterioration of subcortical grey matter (GM) structures, such as the hippocampus. The influence of age×gender interaction on disproportionate GM volume changes might be mediated by hormonal effects on the brain. Hippocampal volume loss appears to become accelerated in the postmenopausal period. This decline might have significant influences on neuroplasticity in the CA1 region of the hippocampus highly vulnerable to pathological influences. Additionally, menopause has been associated with critical pathobiochemical changes involved in neurodegeneration. The micro- and macrostructural alterations and consequent functional deterioration of critical hippocampal regions might result in clinical cognitive impairment-especially if there already is a decline in the cognitive reserve capacity. Several lines of potential vulnerability factors appear to interact in the menopausal period eventually leading to cognitive decline, mild cognitive impairment, or Alzheimer's disease. This focused review aims to delineate the influence of unmodifiable risk factors of neurodegenerative processes, i.e., age and gender, on critical subcortical GM structures in the light of brain derived estrogen effects. The menopausal period appears to be of key importance for the risk of cognitive decline representing a time of special vulnerability for molecular, structural, and functional influences and offering only a narrow window for potential protective effects.

Generation and Partial Characterization of Rabbit Monoclonal Antibody to Amyloid-β Peptide 1-37 (Aβ37). - Mehta, Pankaj D; Blain, Jean-Francois; Freeman, Emily A; Patrick, Bruce A; Barshatzky, Marc; Hrdlicka, Lori A; Mehta, Sangita P; Frackowiak, Janusz; Mazur-Kolecka, Bozena; Wegiel, Jerzy; Patzke, Holger; Miller, David L (J Alzheimers Dis, 2017)
Secreted soluble amyloid-β 1-37 (Aβ37) peptide is one of the prominent Aβ forms next to Aβ40, and is found in cerebrospinal fluid (CSF) and blood. Recent studies have shown the importance of quantitation of CSF Aβ37 levels in combination with Aβ38, Aβ40, and Aβ42 to support the diagnosis of patients with probable Alzheimer's disease (AD), and the value of antibody to Aβ37 to facilitate drug discovery studies. However, the availability of reliable and specific monoclonal antibody to Aβ37 is very limited. Our aims were: 1) to generate and partially characterize rabbit monoclonal antibody (RabmAb) to Aβ37, and 2) to determine whether the antibody detects changes in Aβ37 levels produced by a γ-secretase modulator (GSM). Our generated RabmAb to Aβ37 was found to be specific to Aβ37, since it did not react with Aβ36, Aβ38, Aβ39, Aβ40, and Aβ42 in an ELISA or immunoblotting. The epitope of the antibody was contained in the seven C-terminal residues of Aβ37. The antibody was sensitive enough to measure CSF and plasma Aβ37 levels in ELISA. Immunohistological studies showed the presence of Aβ37-positive deposits in the brain of AD, and Down syndrome persons diagnosed with AD. Our studies also showed that the antibody detected Aβ37 increases in CSF and brains of rodents following treatment with a GSM. Thus, our antibody can be widely applied to AD research, and in a panel based approach it may have potential to support the diagnosis of probable AD, and in testing the effect of GSMs to target AD.

Genetic Stratification to Identify Risk Groups for Alzheimer's Disease. - Marioni, Riccardo E; Campbell, Archie; Hagenaars, Saskia P; Nagy, Reka; Amador, Carmen; Hayward, Caroline; Porteous, David J; Visscher, Peter M; Deary, Ian J (J Alzheimers Dis, 2017)
Stratification by genetic risk factors for Alzheimer's disease (AD) may help identify groups with the greatest disease risk. Biological changes that cause late-onset AD are likely to occur years, if not decades prior to diagnosis. Here, we select a subset of the Generation Scotland: Scottish Family Health Study cohort in a likely preclinical age-range of 60-70 years (subset n = 3,495 with cognitive and genetic data). We test for cognitive differences by polygenic risk scores for AD. The polygenic scores are constructed using all available SNPs, excluding those within a 500 kb distance of the APOE locus. Additive and multiplicative effects of APOE status on these associations are investigated. Small memory decrements were observed in those with high polygenic risk scores for AD (standardized beta -0.04, p = 0.020). These associations were independent of APOE status. There was no difference in AD polygenic scores across APOE haplotypes (p = 0.72). Individuals with high compared to low polygenic risk scores for AD (top and bottom 5% of the distribution) show cognitive decrements, albeit much smaller than for APOE ɛ4ɛ4 compared to ɛ3ɛ3 individuals (2.3 versus 3.5 fewer points on the processing speed test, and 1.8 versus 2.8 fewer points on the memory test). Polygenic risk scores for AD may help identify older individuals at greatest risk of cognitive decline and preclinical AD.

Google Calendar Enhances Prospective Memory in Alzheimer's Disease: A Case Report. - El Haj, Mohamad; Gallouj, Karim; Antoine, Pascal (J Alzheimers Dis, 2017)
We investigated whether an external memory aid (i.e., Google Calendar) would alleviate prospective memory compromise in a patient with mild Alzheimer's disease. The patient was asked in the baseline phase to perform three prospective targeted events (e.g., attending her weekly bridge game at the community club) and three prospective control events (e.g., buying her weekly magazine). The same six prospective events were assessed in the intervention phase but the targeted-events were cued by Google Calendar while the control-events were not. Results showed less omission of the targeted events in the training phase than in the baseline phase, suggesting a positive effect of Google Calendar. This case report offers a unique view into how smartphone calendars may alleviate prospective memory compromise in patients with mild Alzheimer's disease.

The Gut Microbiota and Alzheimer's Disease. - Jiang, Chunmei; Li, Guangning; Huang, Pengru; Liu, Zhou; Zhao, Bin (J Alzheimers Dis, 2017)
The gut microbiota comprises a complex community of microorganism species that resides in our gastrointestinal ecosystem and whose alterations influence not only various gut disorders but also central nervous system disorders such as Alzheimer's disease (AD). AD, the most common form of dementia, is a neurodegenerative disorder associated with impaired cognition and cerebral accumulation of amyloid-β peptides (Aβ). Most notably, the microbiota-gut-brain axis is a bidirectional communication system that is not fully understood, but includes neural, immune, endocrine, and metabolic pathways. Studies in germ-free animals and in animals exposed to pathogenic microbial infections, antibiotics, probiotics, or fecal microbiota transplantation suggest a role for the gut microbiota in host cognition or AD-related pathogenesis. The increased permeability of the gut and blood-brain barrier induced by microbiota dysbiosis may mediate or affect AD pathogenesis and other neurodegenerative disorders, especially those associated with aging. In addition, bacteria populating the gut microbiota can secrete large amounts of amyloids and lipopolysaccharides, which might contribute to the modulation of signaling pathways and the production of proinflammatory cytokines associated with the pathogenesis of AD. Moreover, imbalances in the gut microbiota can induce inflammation that is associated with the pathogenesis of obesity, type 2 diabetes mellitus, and AD. The purpose of this review is to summarize and discuss the current findings that may elucidate the role of the gut microbiota in the development of AD. Understanding the underlying mechanisms may provide new insights into novel therapeutic strategies for AD.

Higher Peripheral TREM2 mRNA Levels Relate to Cognitive Deficits and Hippocampal Atrophy in Alzheimer's Disease and Amnestic Mild Cognitive Impairment. - Tan, Yi Jayne; Ng, Adeline S L; Vipin, Ashwati; Lim, Joseph K W; Chander, Russell J; Ji, Fang; Qiu, Yingwei; Ting, Simon K S; Hameed, Shahul; Lee, Tih-Shih; Zeng, Li; Kandiah, Nagaendran; et al. (J Alzheimers Dis, 2017)
BACKGROUND: Variants in triggering receptor expressed on myeloid cells 2 (TREM2) are associated with increased Alzheimer's disease (AD) risk. Recent studies have reported inconsistent peripheral TREM2 mRNA expression levels and relationship with cognitive scores in AD and mild cognitive impairment (MCI). Additionally, no study has examined the association of peripheral TREM2 levels with neuroimaging measures in AD and MCI. OBJECTIVE: To determine peripheral TREM2 mRNA levels in AD, amnestic MCI (aMCI) and healthy controls, and the association with cognitive performance and brain structural changes. METHODS: We measured peripheral TREM2 mRNA levels in 80 AD, 30 aMCI, and 86 healthy controls using real time polymerase chain reaction. TREM2 levels were correlated with various cognitive performance and brain volumes, correcting for APOE4 status. RESULTS: TREM2 mRNA levels were significantly higher in AD compared to controls and aMCI. Levels did not differ between aMCI and controls. Corrected for APOE4, higher TREM2 levels correlated with lower Mini-Mental State Examination, Montreal Cognitive Assessment (MoCA) and episodic memory scores, and lower total grey matter and right hippocampal volumes. Whole-brain voxel-based morphometry analysis found negative association between TREM2 mRNA levels and grey matter volumes in temporal, parietal and frontal regions. AD subjects with MoCA scores ≤20 had higher TREM2 levels correlating with smaller total grey matter, left hippocampal and right hippocampal volumes. CONCLUSION: Peripheral TREM2 mRNA levels are higher in AD and are associated with AD-related cognitive deficits and hippocampal atrophy. Our findings suggest that TREM2 may be a potential non-invasive peripheral biomarker for AD diagnosis.

Hippocampus and Basal Forebrain Volumetry for Dementia and Mild Cognitive Impairment Diagnosis: Could It Be Useful in Primary Care? - Teipel, Stefan J; Keller, Felix; Thyrian, Jochen R; Strohmaier, Urs; Altiner, Attila; Hoffmann, Wolfgang; Kilimann, Ingo (J Alzheimers Dis, 2017)
BACKGROUND: Once a patient or a knowledgeable informant has noticed decline in memory or other cognitive functions, initiation of early dementia assessment is recommended. Hippocampus and cholinergic basal forebrain (BF) volumetry supports the detection of prodromal and early stages of Alzheimer's disease (AD) dementia in highly selected patient populations. OBJECTIVE: To compare effect size and diagnostic accuracy of hippocampus and BF volumetry between patients recruited in highly specialized versus primary care and to assess the effect of white matter lesions as a proxy for cerebrovascular comorbidity on diagnostic accuracy. METHODS: We determined hippocampus and BF volumes and white matter lesion load from MRI scans of 71 participants included in a primary care intervention trial (clinicaltrials.gov identifier: NCT01401582) and matched 71 participants stemming from a memory clinic. Samples included healthy controls and people with mild cognitive impairment (MCI), AD dementia, mixed dementia, and non-AD related dementias. RESULTS: Volumetric measures reached similar effect sizes and cross-validated levels of accuracy in the primary care and the memory clinic samples for the discrimination of AD and mixed dementia cases from healthy controls. In the primary care MCI cases, volumetric measures reached only random guessing levels of accuracy. White matter lesions had only a modest effect on effect size and diagnostic accuracy. CONCLUSIONS: Hippocampus and BF volumetry may usefully be employed for the identification of AD and mixed dementia, but the detection of MCI does not benefit from the use of these volumetric markers in a primary care setting.

Homocysteine and Real-Space Navigation Performance among Non-Demented Older Adults. - Pařízková, Martina; Andel, Ross; Lerch, Ondřej; Marková, Hana; Gažová, Ivana; Vyhnálek, Martin; Hort, Jakub; Laczó, Jan (J Alzheimers Dis, 2017)
BACKGROUND: High plasma homocysteine (Hcy) level is related to higher risk of Alzheimer's disease (AD) and lower cognitive performance in older adults. OBJECTIVE: To assess the association between plasma Hcy level and real-space navigation performance and the role of vascular risk and protective factors, APOE status, and white matter lesions (WML) on this association. METHODS: Ninety-two non-demented older adults (29 with amnestic mild cognitive impairment, 46 with subjective cognitive decline, and 17 cognitively normal older adults) underwent spatial navigation testing of egocentric, allocentric, and mixed navigation in a real-space analogue of the Morris water maze, neuropsychological examination, blood collection, and MRI brain scan with evaluation of WML. RESULTS: In the regression analyses controlling for age, gender, education, and depressive symptoms, higher plasma Hcy level was related to worse mixed and egocentric (β= 0.31; p = 0.003 and β= 0.23; p = 0.017) but not allocentric (p > 0.05) navigation performance. Additional controlling for vascular risk and protective factors, WML, and APOE status did not modify the results. High total cholesterol and low vitamin B12 and folate levels increased the adverse effect of Hcy on egocentric and mixed navigation. WML did not explain the association between plasma Hcy level and navigation performance. CONCLUSION: Elevated plasma Hcy level may affect real-space navigation performance above and beyond vascular brain changes. This association may be magnified in the presence of high total cholesterol and low folate or vitamin B12 levels. Attention to the level of plasma Hcy may be a viable intervention strategy to prevent decline in spatial navigation in non-demented older adults.

How Different are Quality of Life Ratings for People with Dementia Reported by Their Family Caregivers from Those Reported by the Patients Themselves? - Jacob, Louis; Han, Ji Won; Kim, Tae Hui; Park, Joon Hyuk; Lee, Seok Bum; Lee, Jung Jae; Ryu, Seung-Ho; Kim, Shin-Kyeom; Yoon, Jong Chul; Jhoo, Jin Hyeong; Kim, Jeong Lan; Kwak, Kyung Phil; et al. (J Alzheimers Dis, 2017)
BACKGROUND: Measurements of patient quality of life (QoL) play a major role in the management of dementia. OBJECTIVE: We investigated the self-proxy discrepancy of QoL ratings in the elderly and the impact of dementia severity on the discrepancy. METHODS: QoL of 718 patients with dementia and 651 non-demented elderly were rated by themselves and their caregivers (CG) using the Quality of Life-Alzheimer's Disease (QoL-AD). The impact of the rater on the total and item scores of QoL-AD was analyzed using repeated measures ANOVA and differential response patterns between self and proxy were analyzed using differential item functioning (DIF) analysis. RESULTS: Self-rated scores were higher than CG-rated scores in all diagnostic groups. The interaction between rater and diagnostic group was significant in total QoL-AD score and 5 item scores ('memory', 'marriage', 'chores around the house', 'do things for fun', and 'life as a whole'). The strength of the DIF increased with advancing dementia in these items. CONCLUSION: Self-proxy rating discrepancy of QoL was influenced by the presence and severity of dementia only in five items.

How Does Exercise Reduce the Rate of Age-Associated Cognitive Decline? A Review of Potential Mechanisms. - Kennedy, Greg; Hardman, Roy J; Macpherson, Helen; Scholey, Andrew B; Pipingas, Andrew (J Alzheimers Dis, 2017)
The rate of age-associated cognitive decline varies considerably between individuals. It is important, both on a societal and individual level, to investigate factors that underlie these differences in order to identify those which might realistically slow cognitive decline. Physical activity is one such factor with substantial support in the literature. Regular exercise can positively influence cognitive ability, reduce the rate of cognitive aging, and even reduce the risk of Alzheimer's disease (AD) and other dementias. However, while there is substantial evidence in the extant literature for the effect of exercise on cognition, the processes that mediate this relationship are less clear. This review examines cardiovascular health, production of brain derived neurotrophic factor (BDNF), insulin sensitivity, stress, and inflammation as potential pathways, via which exercise may maintain or improve cognitive functioning, and may be particularly pertinent in the context of the aging brain. A greater understanding of these mechanisms and their potential relationships with exercise and cognition will be invaluable in providing biomarkers for investigating the efficacy of differing exercise regimes on cognitive outcomes.

Humans with Type-2 Diabetes Show Abnormal Long-Term Potentiation-Like Cortical Plasticity Associated with Verbal Learning Deficits. - Fried, Peter J; Schilberg, Lukas; Brem, Anna-Katharine; Saxena, Sadhvi; Wong, Bonnie; Cypess, Aaron M; Horton, Edward S; Pascual-Leone, Alvaro (J Alzheimers Dis, 2017)
BACKGROUND: Type-2 diabetes mellitus (T2DM) accelerates cognitive aging and increases risk of Alzheimer's disease. Rodent models of T2DM show altered synaptic plasticity associated with reduced learning and memory. Humans with T2DM also show cognitive deficits, including reduced learning and memory, but the relationship of these impairments to the efficacy of neuroplastic mechanisms has never been assessed. OBJECTIVE: Our primary objective was to compare mechanisms of cortical plasticity in humans with and without T2DM. Our secondary objective was to relate plasticity measures to standard measures of cognition. METHODS: A prospective cross-sectional cohort study was conducted on 21 adults with T2DM and 15 demographically-similar non-diabetic controls. Long-term potentiation-like plasticity was assessed in primary motor cortex by comparing the amplitude of motor evoked potentials (MEPs) from single-pulse transcranial magnetic stimulation before and after intermittent theta-burst stimulation (iTBS). Plasticity measures were compared between groups and related to neuropsychological scores. RESULTS: In T2DM, iTBS-induced modulation of MEPs was significantly less than controls, even after controlling for potential confounds. Furthermore, in T2DM, modulation of MEPs 10-min post-iTBS was significantly correlated with Rey Auditory Verbal Learning Task (RAVLT) performance. CONCLUSION: Humans with T2DM show abnormal cortico-motor plasticity that is correlated with reduced verbal learning. Since iTBS after-effects and the RAVLT are both NMDA receptor-dependent measures, their relationship in T2DM may reflect brain-wide alterations in the efficacy of NMDA receptors. These findings offer novel mechanistic insights into the brain consequences of T2DM and provide a reliable means to monitor brain health and evaluate the efficacy of clinical interventions.

Identification of Circulating miR-125b as a Potential Biomarker of Alzheimer's Disease in APP/PS1 Transgenic Mouse. - Hong, Honghai; Li, Yang; Su, Baochang (J Alzheimers Dis, 2017)
Alzheimer's disease (AD) is the most common form of dementia, characterized by progressive decline in cognitive abilities of the affected individuals. Biological markers are essential to identify individuals at early stages of the disease for timely therapeutic intervention. Currently, pathological biomarkers are detected either through cerebrospinal fluid analysis or brain imaging, or postmortem, all of which are expensive, invasive, or time consuming. Recently, some studies have shown that circulating miR-125b, miR-181c, miR-9, miR-191-5p, miR-26b-3p, and miR-28-3p may be biomarkers of AD. However, those potential biomarkers are not validated in an AD mouse model. In the current study, we found that circulating miR-125b, miR-9, and miR-191-5p are downregulated, and miR-28-3p is upregulated in an APP/PS1 transgenic mouse model of AD. Furthermore, the correlation analysis shows a positive correlation between the expression of miR-125b and cognitive function of the APP/PS1 transgenic mouse. Moreover, we also determined that the level of serum miR-125b, miR-9, and miR-191-5p were reversed in EGCG-treated APP/PS1 transgenic mouse models. Finally, the expression of miR-125b was significantly downregulated in EGCG-treated SH-SY5Y cells.

Impact of Recruitment Methods in Subjective Cognitive Decline. - Abdelnour, Carla; Rodríguez-Gómez, Octavio; Alegret, Montserrat; Valero, Sergi; Moreno-Grau, Sonia; Sanabria, Ángela; Hernandez, Isabel; Rosende-Roca, Maitee; Vargas, Liliana; Mauleón, Ana; Sánchez, Domingo; Espinosa, Ana; et al. (J Alzheimers Dis, 2017)
BACKGROUND: Recruitment methods can determine sample characteristics in mild cognitive impairment and Alzheimer's disease dementia, but little is known about its influence in subjective cognitive decline (SCD). OBJECTIVE: To determine the influence of two types of recruitment methods in the characteristics of individuals with SCD. METHODS: We select and compare clinical and neuropsychological features, and frequency of APOE ɛ4 allele of 326 subjects with SCD from two cohorts: Open House Initiative (OHI) versus Memory Unit (MU). A logistic regression analysis (LRA), using gender and years of education as covariates, was used to examine the neuropsychological variables. RESULTS: The OHI sample were mostly women (75.9% versus 64.5%, p < 0.05), with higher educational level (12.15 [3.71] versus 10.70 [3.80] years, p = 0.001), and more family history of dementia (138 [62.7%] versus 44 [41.5%], p < 0.001) than the MU sample. Also, the OHI sample showed better overall neuropsychological performance than the MU sample, and after a LRA, this trend continued in automatic response inhibition capacity, abstract reasoning, and recognition memory. We did not find differences in age, depression history, and/or APOE ɛ4 allele frequency. CONCLUSION: SCD subjects showed different demographic and neuropsychological characteristics depending on the recruitment method, which should be taken into account in the design of research studies with this target population.

Implication of the APP Gene in Intellectual Abilities. - Myrum, Craig; Nikolaienko, Oleksii; Bramham, Clive R; Haavik, Jan; Zayats, Tetyana (J Alzheimers Dis, 2017)
BACKGROUND: Cognitive functions are highly heritable and polygenic, though the source of this genetic influence is unclear. On the neurobiological level, these functions rely on effective neuroplasticity, in which the activity-regulated cytoskeleton associated protein (ARC) plays an essential role. OBJECTIVES: To examine whether the ARC gene complex may contribute to the genetic components of intellectual function given the crucial role of ARC in brain plasticity and memory formation. METHODS: The ARC complex was tested for association with intelligence (IQ) in children from the Avon Longitudinal Study of Parents and Children (ALSPAC, N = 5,165). As Alzheimer's disease (AD) shares genetics with cognitive functioning, the association was followed up in an AD sample (17,008 cases, 37,154 controls). RESULTS: The ARC complex revealed association with verbal and total IQ (empirical p = 0.027 and 0.041, respectively) in the ALSPAC. The strongest single variant signal (rs2830077; empirical p = 0.018), within the APP gene, was confirmed in the AD sample (p = 2.76E-03). Functional analyses of this variant showed its preferential binding to the transcription factor CP2. DISCUSSION: This study implicates APP in childhood IQ. While follow-up studies are needed, this observation could help elucidate the etiology of disorders associated with cognitive dysfunction, such as AD.

Improved Cerebrospinal Fluid-Based Discrimination between Alzheimer's Disease Patients and Controls after Correction for Ventricular Volumes. - van Waalwijk van Doorn, Linda J C; Gispert, Juan D; Kuiperij, H Bea; Claassen, Jurgen A H R; Arighi, Andrea; Baldeiras, Ines; Blennow, Kaj; Bozzali, Marco; Castelo-Branco, Miguel; Cavedo, Enrica; Emek-Savaş, Derya D; Eren, Erden; et al. (J Alzheimers Dis, 2017)
Cerebrospinal fluid (CSF) biomarkers may support the diagnosis of Alzheimer's disease (AD). We studied if the diagnostic power of AD CSF biomarker concentrations, i.e., Aβ42, total tau (t-tau), and phosphorylated tau (p-tau), is affected by differences in lateral ventricular volume (VV), using CSF biomarker data and magnetic resonance imaging (MRI) scans of 730 subjects, from 13 European Memory Clinics. We developed a Matlab-algorithm for standardized automated segmentation analysis of T1 weighted MRI scans in SPM8 for determining VV, and computed its ratio with total intracranial volume (TIV) as proxy for total CSF volume. The diagnostic power of CSF biomarkers (and their combination), either corrected for VV/TIV ratio or not, was determined by ROC analysis. CSF Aβ42 levels inversely correlated to VV/TIV in the whole study population (Aβ42: r = -0.28; p < 0.0001). For CSF t-tau and p-tau, this association only reached statistical significance in the combined MCI and AD group (t-tau: r = -0.15; p-tau: r = -0.13; both p < 0.01). Correction for differences in VV/TIV improved the differentiation of AD versus controls based on CSF Aβ42 alone (AUC: 0.75 versus 0.81) or in combination with t-tau (AUC: 0.81 versus 0.91). In conclusion, differences in VV may be an important confounder in interpreting CSF Aβ42 levels.

An Improved Drugs Screening System Reveals that Baicalein Ameliorates the Aβ/AMPA/NMDA-Induced Depolarization of Neurons. - Lin, Tian-Syuan; Tsai, Han-Jung; Lee, Chih-Han; Song, Yan-Qing; Huang, Rih-Sheng; Hsieh-Li, Hsiu-Mei; Liang, Mei-Chih; Lin, Yenshou (J Alzheimers Dis, 2017)
The presence of amyloid-β (Aβ) plaque and tau protein hyperphosphorylation in brain tissue is the pathological hallmark of Alzheimer's disease (AD). At least some Aβ neurotoxicity is caused by the presence of excess glutamate that has been induced by Aβ accumulation. Memantine is currently the only NMDA receptor inhibitor approved for treating moderate-to-severe AD patients. We utilized primary cortical neurons and DiBAC4(3), a slow-response voltage sensitive fluorescence dye, to create a novel system for screening herbal medicines that allows the identification of pure compounds able to ameliorate Aβ-induced abnormal depolarization. The intensity of DiBAC4(3) fluorescence was increased when primary neurons were stimulated by Aβ; furthermore, pre-treatment with memantine abolished this change. Using this system, we identified six crude extracts made from herbal medicines that effectively alleviated this Aβ-induced abnormal depolarization. Among these herbal medicines, one pure compound, baicalein, which was known to be present in Scutellaria baricalensis and is known to improve memory using an AD mouse model, was identified by our assay. However, the compound's molecular mechanism remained unknown. We found that baicalein, in addition to inhibiting Aβ-induced depolarization, possibly functions as an antagonist of AMPA and NMDA receptors. Taken together, we have established a system/platform to identify herbal medicines that ameliorate Aβ-induced depolarization of neurons. Equally important, baicalein is a candidate drug with great potential for the treatment of AD patients.

In vivo Patterns of Tau Pathology, Amyloid-β Burden, and Neuronal Dysfunction in Clinical Variants of Alzheimer's Disease. - Dronse, Julian; Fliessbach, Klaus; Bischof, Gérard N; von Reutern, Boris; Faber, Jennifer; Hammes, Jochen; Kuhnert, Georg; Neumaier, Bernd; Onur, Oezguer A; Kukolja, Juraj; van Eimeren, Thilo; Jessen, Frank; et al. (J Alzheimers Dis, 2017)
The clinical heterogeneity of Alzheimer's disease is not reflected in the rather diffuse cortical deposition of amyloid-β. We assessed the relationship between clinical symptoms, in vivo tau pathology, amyloid distribution, and hypometabolism in variants of Alzheimer's disease using novel multimodal PET imaging techniques. Tau pathology was primarily observed in brain regions related to clinical symptoms and overlapped with areas of hypometabolism. In contrast, amyloid-β deposition was diffusely distributed over the entire cortex. Tau PET imaging may thus serve as a valuable biomarker for the localization of neuronal injury in vivo and may help to validate atypical subtypes of Alzheimer's disease.

Increased Carbohydrate Intake is Associated with Poorer Performance in Verbal Memory and Attention in an APOE Genotype-Dependent Manner. - Gardener, Samantha L; Rainey-Smith, Stephanie R; Sohrabi, Hamid R; Weinborn, Michael; Verdile, Giuseppe; Fernando, W M A D Binosha; Lim, Yen Ying; Harrington, Karra; Burnham, Samantha; Taddei, Kevin; Masters, Colin L; Macaulay, Stuart L; et al. (J Alzheimers Dis, 2017)
Evidence suggests that a diet low in carbohydrates can impact on cognitive performance among those with Alzheimer's disease (AD). However, there is a lack of data assessing this relationship among cognitively normal (CN) older adults at increased future risk of developing AD due to carriage of the apolipoprotein E (APOE) ɛ4 allele. We assessed the cross-sectional association between carbohydrate intake, cognitive performance, and cerebral amyloid-β (Aβ) load in CN older adults, genotyped for APOEɛ4 allele carrier status. Greater carbohydrate intake was associated with poorer performance in verbal memory in APOEɛ4 allele non-carriers, and poorer performance in attention in APOEɛ4 allele carriers. There were no associations between carbohydrate intake and cerebral Aβ load. These results provide support to the idea that decreasing carbohydrate intake may offer neurocognitive benefits, with specific cognitive domains affected in an APOE genotype-dependent manner. These findings warrant further investigation utilizing a longitudinal study design.

Increased Plasma Homocysteine Level is Associated with Executive Dysfunction in Type 2 Diabetic Patients with Mild Cognitive Impairment. - Tian, Sai; Han, Jing; Huang, Rong; Sun, Jie; Cai, Rongrong; Shen, Yanjue; Wang, Shaohua (J Alzheimers Dis, 2017)
BACKGROUND: Homocysteine (Hcy) is involved in the pathogenesis of type 2 diabetes mellitus (T2DM) and Alzheimer's disease. OBJECTIVE: We aimed to investigate the role of Hcy in T2DM patients with mild cognitive impairment (MCI), and to determine whether methylene tetrahydrofolate reductase (MTHFR) C677T or cystathionine beta-synthase (CBS) 844ins68 polymorphism is related to T2DM-associated MCI. METHODS: We recruited 285 T2DM patients and divided them into two groups, 140 patients with MCI, and 145 healthy-cognition controls, on the basis of Montreal Cognitive Assessment (MoCA) scores. Demographic characteristics, clinical parameters, and neuropsychological tests were assessed. MTHFR C677T and CBS 844ins68 polymorphisms were analyzed. RESULTS: The MCI group exhibited significantly higher plasma total Hcy (tHcy) levels than control group (p < 0.001). Plasma tHcy level was negatively correlated with MoCA scores (p = 0.002), but positively associated with Trail Making Test A and B scores (p = 0.044; p = 0.005, respectively). Multivariable logistic regression model showed that high tHcy level was an independent factor for MCI in T2DM patients. No significant difference was observed in the genotype or allele distributions of MTHFR and CBS between MCI and control groups. We did not find significant MCI risks in MTHFR T allele compared with C allele, and in CBS I allele compared with D allele (OR = 1.361, p = 0.067; OR = 1.048, p = 0.909, respectively). CONCLUSION: Increased plasma tHcy level was significantly related to T2DM-associated MCI, especially executive dysfunction. Further investigation with a large population size should be conducted to confirm these findings.

Increased Transforming Growth Factor β2 in the Neocortex of Alzheimer's Disease and Dementia with Lewy Bodies is Correlated with Disease Severity and Soluble Aβ42 Load. - Chong, Joyce R; Chai, Yuek Ling; Lee, Jasinda H; Howlett, David; Attems, Johannes; Ballard, Clive G; Aarsland, Dag; Francis, Paul T; Chen, Christopher P; Lai, Mitchell K P (J Alzheimers Dis, 2017)
BACKGROUND: Of the three transforming growth factor (TGF)-β isoforms known, TGFβ1 deficits have been widely reported in Alzheimer's disease (AD) and studied as a potential therapeutic target. In contrast, the status of TGFβ2, which has been shown to mediate amyloid-β (Aβ)-mediated neuronal death, are unclear both in AD and in Lewy body dementias (LBD) with differential neuritic plaque and neurofibrillary tangle burden. OBJECTIVE: To measure neocortical TGFβ2 levels and their correlations with neuropathological and clinical markers of disease severity in a well-characterized cohort of AD as well as two clinical subtypes of LBD, dementia with Lewy bodies (DLB) and Parkinson's disease dementia (PDD), known to manifest relatively high and low Aβ plaque burden, respectively. METHODS: Postmortem samples from temporal cortex (BA21) were measured for TGFβ2 using a Luminex-based platform, and correlated with scores for neuritic plaques, neurofibrillary tangles, α-synuclein pathology, dementia severity (as measured by annual decline of Mini-Mental State Examination scores) as well as soluble and total fractions of brain Aβ42. RESULTS: TGFβ2 was significantly increased in AD and DLB, but not in PDD. TGFβ2 also correlated with scores for neurofibrillary tangles, Lewy bodies (within the LBD group), dementia severity, and soluble Aβ42 concentration, but not with neuritic plaque scores, total Aβ42, or monomeric α-synuclein immunoreactivity. CONCLUSIONS: TGFβ2 is increased in the temporal cortex of AD and DLB, and its correlations with neuropathological and clinical markers of disease severity as well as with soluble Aβ42 load suggest a potential pathogenic role in mediating the neurotoxicity of non-fibrillar Aβ. Our study also indicates the potential utility of targeting TGFβ2 in pharmacotherapeutic approaches to AD and DLB.

Intracerebroventricular Streptozotocin Induces Obesity and Dementia in Lewis Rats. - Bloch, Konstantin; Gil-Ad, Irit; Vanichkin, Alexey; Hornfeld, Shay Henry; Koroukhov, Nickolay; Taler, Michal; Vardi, Pnina; Weizman, Abraham (J Alzheimers Dis, 2017)
BACKGROUND: Animal models of dementia associated with metabolic abnormalities play an important role in understanding the bidirectional relationships between these pathologies. Rodent strains develop cognitive dysfunctions without alteration of peripheral metabolism following intracerebroventricular administration of streptozotocin (icv-STZ). OBJECTIVE: We aimed to estimate the effect of icv-STZ on cognitive functions and peripheral metabolism in Lewis rats, which are rarely used for the induction of cognitive abnormalities. METHODS: Inbred adult Lewis rats were treated with single icv-STZ (3 mg/kg). Cognitive functions were assessed using Morris water maze (MWM) test and locomotion by the Open Field test. Metabolic alterations were studied using histological and biochemical analysis of brain and peripheral tissues. RESULTS: The icv-STZ induced rapid weight decline during the first two weeks. Thereafter, the rats showed an accelerated weight gain. Three months after the icv-STZ treatment, the rats were severely obese and revealed fatty liver, pancreatic islet hypertrophy, significantly elevated levels of blood insulin, leptin, and adiponectin, but intact peripheral glucose homeostasis. The icv-STZ rats expressed amyloid-β deposits in blood vessels of leptomeningeal area, microgliosis, astrogliosis, and spongiosis in fimbria-fornix area of hippocampus. Locomotor activities of icv-STZ treated and sham-operated rats were similar. In the MWM test, the icv-STZ treated rats demonstrated severely impaired spatial learning during both acquisition and reversal phases. CONCLUSIONS: Icv-STZ treated Lewis rats develop severe dementia associated with obesity and peripheral metabolic abnormalities. This animal model may be useful for exploring the pathophysiological relationship between obesity and dementia and provides a new tool for development of effective therapy.

Intranasal Insulin Transport is Preserved in Aged SAMP8 Mice and is Altered by Albumin and Insulin Receptor Inhibition. - Rhea, Elizabeth M; Humann, Samantha R; Nirkhe, Surabhi; Farr, Susan A; Morley, John E; Banks, William A (J Alzheimers Dis, 2017)
Insulin delivered to the level of the cribriform plate (intranasal insulin) is being investigated for its ability to enhance memory in people with Alzheimer's disease (AD). Recent work has shown intranasal insulin can be detected in young CD-1 mice within 5 min and is still present 60 min after injection. The current study determined whether intranasal insulin transport and the subsequent brain distribution of insulin varies in young, healthy mice (CD-1) compared to those with an AD-like phenotype (aged SAMP8) or those pre-disposed to develop such a phenotype (young SAMP8). We showed transport does not vary among these three mouse cohorts, suggesting that intranasal uptake and brain pharmacokinetics do not differ with AD-like signs or the genetic predisposition to developing them. We found that co-administration with bovine serum albumin increased levels of insulin in most brain regions. In addition, the insulin receptor inhibitor, S961, decreases the amount of insulin transported throughout the brain after intranasal injection. These results show insulin delivery to the brain by intranasal administration can be modified with agents such as albumin, may be dependent on the insulin receptor, and is not affected by an AD-like phenotype as presented by the SAMP8 mouse.

Investigating Simulated Driving Errors in Amnestic Single- and Multiple-Domain Mild Cognitive Impairment. - Hird, Megan A; Vesely, Kristin A; Fischer, Corinne E; Graham, Simon J; Naglie, Gary; Schweizer, Tom A (J Alzheimers Dis, 2017)
The areas of driving impairment characteristic of mild cognitive impairment (MCI) remain unclear. This study compared the simulated driving performance of 24 individuals with MCI, including amnestic single-domain (sd-MCI, n = 11) and amnestic multiple-domain MCI (md-MCI, n = 13), and 20 age-matched controls. Individuals with MCI committed over twice as many driving errors (20.0 versus 9.9), demonstrated difficulty with lane maintenance, and committed more errors during left turns with traffic compared to healthy controls. Specifically, individuals with md-MCI demonstrated greater driving difficulty compared to healthy controls, relative to those with sd-MCI. Differentiating between different subtypes of MCI may be important when evaluating driving safety.

Iron Concentration in Deep Gray Matter Structures is Associated with Worse Visual Memory Performance in Healthy Young Adults. - Darnai, Gergely; Nagy, Szilvia Anett; Horváth, Réka; Ács, Péter; Perlaki, Gábor; Orsi, Gergely; Kovács, Norbert; Altbäcker, Anna; Plózer, Enikő; Tényi, Dalma; Weintraut, Rita; Schwarcz, Attila; et al. (J Alzheimers Dis, 2017)
Abnormally high deposition of iron can contribute to neurodegenerative disorders with cognitive impairment. Since previous studies investigating cognition-brain iron accumulation relationships focused on elderly people, our aim was to explore the association between iron concentration in subcortical nuclei and two types of memory performances in a healthy young population. Gender difference was found only in the globus pallidus. Our results showed that iron load characterized by R2* value on the MRI in the caudate and putamen was related to visual memory, while verbal memory was unrelated to iron concentration.

Left Frontal Hub Connectivity during Memory Performance Supports Reserve in Aging and Mild Cognitive Impairment. - Franzmeier, Nicolai; Hartmann, Julia C; Taylor, Alexander N W; Araque Caballero, Miguel Á; Simon-Vermot, Lee; Buerger, Katharina; Kambeitz-Ilankovic, Lana M; Ertl-Wagner, Birgit; Mueller, Claudia; Catak, Cihan; Janowitz, Daniel; Stahl, Robert; et al. (J Alzheimers Dis, 2017)
Reserve in aging and Alzheimer's disease (AD) is defined as maintaining cognition at a relatively high level in the presence of neurodegeneration, an ability often associated with higher education among other life factors. Recent evidence suggests that higher resting-state functional connectivity within the frontoparietal control network, specifically the left frontal cortex (LFC) hub, contributes to higher reserve. Following up these previous resting-state fMRI findings, we probed memory-task related functional connectivity of the LFC hub as a neural substrate of reserve. In elderly controls (CN, n = 37) and patients with mild cognitive impairment (MCI, n = 17), we assessed global connectivity of the LFC hub during successful face-name association learning, using generalized psychophysiological interaction analyses. Reserve was quantified as residualized memory performance, accounted for gender and proxies of neurodegeneration (age, hippocampus atrophy, and APOE genotype). We found that greater education was associated with higher LFC-connectivity in both CN and MCI during successful memory. Furthermore, higher LFC-connectivity predicted higher residualized memory (i.e., reserve). These results suggest that higher LFC-connectivity contributes to reserve in both healthy and pathological aging.

Levetiracetam Alters Oscillatory Connectivity in Alzheimer's Disease. - Musaeus, Christian S; Shafi, Mouhsin M; Santarnecchi, Emiliano; Herman, Susan T; Press, Daniel Z (J Alzheimers Dis, 2017)
Seizures occur at a higher frequency in people with Alzheimer's disease (AD) but overt, clinically obvious events are infrequent. Evidence from animal models and studies in mild cognitive impairment suggest that subclinical epileptic discharges may play a role in the clinical and pathophysiological manifestations of AD. In this feasibility study, the neurophysiological and cognitive effects of acute administration of levetiracetam (LEV) are measured in patients with mild AD to test whether it could have a therapeutic benefit. AD participants were administered low dose LEV (2.5 mg/kg), higher dose LEV (7.5 mg/kg), or placebo in a double-blind, within-subject repeated measures study with EEG recorded at rest before and after administration. After administration of higher dose of LEV, we found significant decreases in coherence in the delta band (1-3.99 Hz) and increases in the low beta (13-17.99 Hz) and the high beta band (24-29.99 Hz). Furthermore, we found trends toward increased power in the frontal and central regions in the high beta band (24-29.99 Hz). However, there were no significant changes in cognitive performance after this single dose administration. The pattern of decreased coherence in the lower frequency bands and increased coherence in the higher frequency bands suggests a beneficial effect of LEV for patients with AD. Larger longitudinal studies and studies with healthy age-matched controls are needed to determine whether this represents a relative normalization of EEG patterns, whether it is unique to AD as compared to normal aging, and whether longer term administration is associated with a beneficial clinical effect.

Lipid Peroxidation Markers in Coronary Artery Disease Patients with Possible Vascular Mild Cognitive Impairment. - Suridjan, Ivonne; Herrmann, Nathan; Adibfar, Alex; Saleem, Mahwesh; Andreazza, Ana; Oh, Paul I; Lanctôt, Krista L (J Alzheimers Dis, 2017)
This study examined associations between lipid peroxidation markers and cognition, and associations between these markers and cognitive response to an exercise intervention program, in adults with coronary artery disease at risk of dementia. Lipid peroxidation products were measured in serum in 118 patients (29 possible vascular mild cognitive impairment and 89 controls). Ratios of early- (lipid hydroperoxides, LPH) to late-stage (8-isoprostane, 8-ISO; 4-hydroxy-2-nonenal, 4-HNE) lipid peroxidation products were calculated. Cognitive performance was assessed before and at completion of a 24-week exercise intervention program. A global effect of group on lipid peroxidation markers was observed, adjusting for sex, years of education, and cardiopulmonary fitness (main effect of group F (3,102) = 2.957, p = 0.036). Lower lipid peroxidation at baseline, as determined by lower 8-ISO concentration, was associated with greater improvement in verbal memory (F (1, 64) = 4.738, p = 0.03) and executive function (F (1, 64) = 5.219, p = 0.026) performance. Similarly, higher ratios of 8-ISO/LPH (F (1, 65) = 6.592, p = 0.013) and (8-ISO+4-HNE) to LPH (F (1, 65) = 3.857, p = 0.054), were associated with less improvement in executive function performance over a 24-week exercise intervention. Lipid peroxidation may be a biomarker of early vascular cognitive impairment, and elevated lipid peroxidation might limit the cognitive benefits of exercise in this high-risk population.

Lipidomic Profiles in Diabetes and Dementia. - Huynh, Kevin; Martins, Ralph N; Meikle, Peter J (J Alzheimers Dis, 2017)
Lipids are a diverse class of hydrophobic and amphiphilic molecules which make up the bulk of most biological systems and are essential for human life. The role of lipids in health and disease has been recognized for many decades, as evidenced by the early identification of cholesterol as an important risk factor of heart disease and the development and introduction of statins as a one of the most successful therapeutic interventions to date. While several studies have demonstrated an increased risk of dementia, including Alzheimer's disease (AD), in those with diabetes mellitus, the nature of this risk is not well understood. Recent developments in the field of lipidomics, driven primarily by technological advances in high pressure liquid chromatography and particularly mass spectrometry, have enabled the detailed characterization of the many hundreds of individual lipid species in mammalian systems and their association with disease states. Diabetes mellitus and AD have received particular attention due to their prominence in Western societies as a result of the ongoing obesity epidemic and the aging populations. In this review, we examine how these lipidomic studies are informing on the relationship between lipid metabolism with diabetes and AD and how this may inform on the common pathological pathways that link diabetes risk with dementia.

A Lipidomics Approach to Assess the Association Between Plasma Sphingolipids and Verbal Memory Performance in Coronary Artery Disease Patients Undertaking Cardiac Rehabilitation: A C18:0 Signature for Cognitive Response to Exercise. - Saleem, Mahwesh; Herrmann, Nathan; Dinoff, Adam; Mielke, Michelle M; Oh, Paul I; Shammi, Prathiba; Cao, Xingshan; Venkata, Swarajya Lakshmi Vattem; Haughey, Norman J; Lanctôt, Krista L (J Alzheimers Dis, 2017)
BACKGROUND: Early subtle deficits in verbal memory, which may indicate early neural risk, are common in patients with coronary artery disease (CAD). While exercise can improve cognition, cognitive response to exercise is heterogeneous. Sphingolipids have been associated with the development and progression of CAD, and impairments in sphingolipid metabolism may play roles in neurodegeneration and in the neural adaptation response to exercise. OBJECTIVE: In this study, change in plasma concentrations of sphingolipids was assessed in relation to change in verbal memory performance and in other cognitive domains among CAD subjects undertaking a 6-month cardiac rehabilitation (CR) program. METHODS: Patients with CAD (n = 120, mean age = 64±6 y, 84% male, years of education = 16±3) underwent CR with neuropsychological assessments and blood collected at baseline, 3-, and 6-months. Z-scores based on age, gender, and education were combined for verbal memory, visuospatial memory, processing speed, executive function, and global cognition tasks to calculate cognitive domain Z-scores. Plasma sphingolipid concentrations were measured from fasting blood samples using high performance liquid chromatography coupled electrospray ionization tandem mass spectrometry (LC/MS/MS). Mixed models were used to identify sphingolipids significantly associated with performance in verbal memory and other cognitive domains, adjusting for potential confounders. RESULTS: A decrease in ceramide C18:0 concentration was significantly associated with improvement in verbal memory performance (b[SE] = -0.51 [0.25], p = 0.04), visuospatial memory (b[SE] = -0.44 [0.22], p = 0.05), processing speed (b[SE] = -0.89 [0.32], p = 0.007), and global cognition (b[SE] = -1.47 [0.59], p = 0.01) over 6 months of CR. CONCLUSIONS: Plasma ceramide C18:0 concentrations may be a sensitive marker of cognitive response to exercise in patients with CAD.

A Longitudinal Study on Resting State Functional Connectivity in Behavioral Variant Frontotemporal Dementia and Alzheimer's Disease. - Hafkemeijer, Anne; Möller, Christiane; Dopper, Elise G P; Jiskoot, Lize C; van den Berg-Huysmans, Annette A; van Swieten, John C; van der Flier, Wiesje M; Vrenken, Hugo; Pijnenburg, Yolande A L; Barkhof, Frederik; Scheltens, Philip; van der Grond, Jeroen; et al. (J Alzheimers Dis, 2017)
BACKGROUND/OBJECTIVE: Alzheimer's disease (AD) and behavioral variant frontotemporal dementia (bvFTD) are the most common types of early-onset dementia. We applied longitudinal resting state functional magnetic resonance imaging (fMRI) to delineate functional brain connections relevant for disease progression and diagnostic accuracy. METHODS: We used two-center resting state fMRI data of 20 AD patients (65.1±8.0 years), 12 bvFTD patients (64.7±5.4 years), and 22 control subjects (63.8±5.0 years) at baseline and 1.8-year follow-up. We used whole-network and voxel-based network-to-region analyses to study group differences in functional connectivity at baseline and follow-up, and longitudinal changes in connectivity within and between groups. RESULTS: At baseline, connectivity between paracingulate gyrus and executive control network, between cuneal cortex and medial visual network, and between paracingulate gyrus and salience network was higher in AD compared with controls. These differences were also present after 1.8 years. At follow-up, connectivity between angular gyrus and right frontoparietal network, and between paracingulate gyrus and default mode network was lower in bvFTD compared with controls, and lower compared with AD between anterior cingulate gyrus and executive control network, and between lateral occipital cortex and medial visual network. Over time, connectivity decreased in AD between precuneus and right frontoparietal network and in bvFTD between inferior frontal gyrus and left frontoparietal network. Longitudinal changes in connectivity between supramarginal gyrus and right frontoparietal network differ between both patient groups and controls. CONCLUSION: We found disease-specific brain regions with longitudinal connectivity changes. This suggests the potential of longitudinal resting state fMRI to delineate regions relevant for disease progression and for diagnostic accuracy, although no group differences in longitudinal changes in the direct comparison of AD and bvFTD were found.

Long-Term Maintenance of Executive-Related Oculomotor Improvements in Older Adults with Self-Reported Cognitive Complaints Following a 24-Week Multiple Modality Exercise Program. - Shellington, Erin M; Heath, Matthew; Gill, Dawn P; Petrella, Robert J (J Alzheimers Dis, 2017)
Adults (≥55 years) with self-reported cognitive complaints (sCC) were randomized to: multiple-modality exercise (M2), or multiple-modality plus mind-motor exercise (M4), for 24-weeks. Participants (n = 58) were assessed on antisaccade reaction time (RT) to examine executive-related oculomotor control and self-reported physical activity (PA) at pre-intervention (V0), post-intervention (V1), and 52-weeks follow-up (V2). We previously reported significant improvements in antisaccade RT of 23 ms at V1, in both groups. We now report maintenance of antisaccade RT improvement from V1 to V2, t(57) = 0.8, p = 0.45, and improved PA from V1 to V2, t(56) = -2.4, p = 0.02. Improvements in executive-related oculomotor control attained at V1 were maintained at V2.

Low Arousal Positive Emotional Stimuli Attenuate Aberrant Working Memory Processing in Persons with Mild Cognitive Impairment. - Broster, Lucas S; Jenkins, Shonna L; Holmes, Sarah D; Jicha, Gregory A; Jiang, Yang (J Alzheimers Dis, 2017)
Emotional enhancement effects on memory have been reported to mitigate the pathophysiology of Alzheimer's disease (AD). However, relative to their manifestation in persons without pathologic aging, these effects may be reduced in magnitude or even deleterious, especially in tasks that more closely model ecologic memory performance. Based upon a synthesis of such reports, we hypothesized that in persons with AD low arousal positive stimuli would evoke relatively intact emotional enhancement effects, but that high arousal negative stimuli would evoke disordered emotional enhancement effects. To assess this, participants with and without mild cognitive impairment (MCI) presumed to be due to AD performed an emotionally-valenced short-term memory task while encephalography was recorded. Results indicated that for persons with MCI, high arousal negative stimuli led to working memory processing patterns previously associated with MCI presumed due to AD and dementia of the Alzheimer-type. In contrast, low arousal positive stimuli evoked a processing pattern similar to MCI participants' unaffected spouses. Our current findings suggest that low arousal positive stimuli attenuate working memory deficits of MCI due to AD.

Low Cognitive Awareness, but Not Complaint, is a Good Marker of Preclinical Alzheimer's Disease. - Cacciamani, Federica; Tandetnik, Caroline; Gagliardi, Geoffroy; Bertin, Hugo; Habert, Marie-Odile; Hampel, Harald; Boukadida, Laurie; Révillon, Marie; Epelbaum, Stéphane; Dubois, Bruno (J Alzheimers Dis, 2017)
BACKGROUND: Subjective cognitive decline (SCD) may result from many conditions, including Alzheimer's disease (AD). OBJECTIVE: In this study, we searched for a specific pattern of SCD in asymptomatic individuals at risk for AD. METHODS: Cognitively normal older adults (N = 318) reporting SCD and their informants were enrolled in the INSIGHT-PreAD cohort. We examined the relationship between six SCD measures and both cognitive scores and AD neuroimaging markers (amyloid burden, hippocampal atrophy and brain hypometabolism). An awareness of cognitive decline index (ACDI) has been introduced based on the subject-informant discrepancy in a questionnaire of SCD and participants with low versus high awareness were compared. RESULTS: Scores in the INSIGHT-PreAD SCD questionnaires did not correlate with AD neuroimaging markers. As well, no correlation has been found between SCD measures and cognitive scores. Comparing subjects with a low (n = 19) and high (n = 86) level of awareness, no significant difference in terms of demography, neuropsychiatric symptoms, autonomy, quality of life, cognition, and hippocampal volume was found. However, the "low awareness" group showed greater amyloid burden and lower cortical metabolism, compared to the "high awareness" group. CONCLUSION: This study provided additional evidence that reporting SCD by itself is not a specific symptom of preclinical AD. Conversely, a low cognitive awareness (namely, when subjects report fewer difficulties than their relatives do) may represent a very early form of anosognosia and serve as a specific indicator of preclinical AD. This finding is of key importance as an enrichment factor to consider in both clinical practice and research trials.

Low Prevalence and Clinical Effect of Vascular Risk Factors in Early-Onset Alzheimer's Disease. - Chen, Yaohua; Sillaire, Adeline Rollin; Dallongeville, Jean; Skrobala, Emilie; Wallon, David; Dubois, Bruno; Hannequin, Didier; Pasquier, Florence (J Alzheimers Dis, 2017)
BACKGROUND: Determinants of early-onset Alzheimer's disease (EOAD) are not well known. In late-onset AD, vascular risk factors (VRFs) are associated with earlier clinical manifestation. OBJECTIVE: The objective of this study was to assess the putative association between VRFs and EOAD. METHODS: We studied participants with dementia meeting criteria for EOAD (recruited into the French CoMAJ prospective cohort study from 1 June 2009 to 28 February 2014) and age-, gender-matched controls (ratio 1:3, drawn randomly from the French MONA-LISA population-based survey between 2005 and 2007). Demographic data, VRFs, comorbidities, treatments, and APOE genotypes were compared in multivariable logistic regression analyses. RESULTS: We studied 102 participants with dementia (mean±standard deviation age: 59.5±3.8; women: 59.8%) and 306 controls. Compared with controls, EOAD participants had spent less time in formal education (9.9±2.9 versus 11.7±3.8 y; p < 0.0001), were less likely to be regular alcohol consumers (p < 0.0001), had a lower body mass index (-2 kg/m2; p < 0.0004), and a lower mean systolic blood pressure (-6.2 mmHg; p = 0.0036). The prevalence of APOE ɛ4 allele was higher in participants with dementia than in controls (50% versus 29.4%; p = 0.0002), as was the prevalence of depression (48% versus 32%; p < 0.001). Similar results were observed in multivariable analysis. Compared with EOAD participants lacking VRFs, EOAD participants with at least one VRF had a higher prevalence of depression (29.6% versus 53.3%, respectively; p = 0.03). CONCLUSION: The prevalence of VRFs is not elevated in EOAD patients (in contrast to older AD patients). Extensive genetic testing should be considered more frequently in the context of EOAD.

Macrophage Migration Inhibitory Factor is Associated with Biomarkers of Alzheimer's Disease Pathology and Predicts Cognitive Decline in Mild Cognitive Impairment and Mild Dementia. - Oikonomidi, Aikaterini; Tautvydaitė, Domilė; Gholamrezaee, Mehdi M; Henry, Hugues; Bacher, Michael; Popp, Julius (J Alzheimers Dis, 2017)
BACKGROUND: Macrophage migration inhibitory factor (MIF) is a pro-inflammatory protein playing a regulatory role in the immune response. First evidence from in vitro and animal studies suggests that MIF may be involved in the development of Alzheimer's disease (AD) pathology. OBJECTIVE: To address in older subjects (i) the relationships between AD pathology and MIF plasma and cerebrospinal fluid (CSF) levels; and (ii) to investigate whether increased MIF-related systemic and CNS inflammation is associated with clinical disease progression. METHODS: CSF and plasma concentrations of MIF as well as biomarkers of amyloid, neuronal injury, and tau hyperphosphorylation (CSF Aβ1-42, tau, and ptau, respectively) were assessed in 97 subjects with MCI or mild dementia (cognitive impairment, CI) and 52 healthy volunteers with normal cognition. Clinical and neuropsychological evaluations were performed at inclusion and at follow up visits. RESULTS: CSF MIF levels were higher in participants with CI with an AD CSF biomarker profile, but not in CI with a non-AD profile, compared to the healthy controls. Higher MIF CSF levels were associated with higher CSF tau and ptau and lower CSF Aβ1-42 after adjusting for potential confounders. In CI, MIF CSF independently predicted cognitive decline at a follow-up visit after controlling for potential confounders including CSF Aβ1-42 and tau levels. CONCLUSION: Our study provides evidence that MIF-related inflammation is related to amyloid pathology, tau hyperphosphorylation, and neuronal injury at the early clinical stages of AD. Higher MIF CSF levels are associated with accelerated cognitive decline in MCI and mild dementia.

Memory Correlates of Alzheimer's Disease Cerebrospinal Fluid Markers: A Longitudinal Cohort Study. - Reijs, Babette L R; Ramakers, Inez H G B; Köhler, Sebastian; Teunissen, Charlotte E; Koel-Simmelink, Marleen; Nathan, Pradeep J; Tsolaki, Magda; Wahlund, Lars-Olof; Waldemar, Gunhild; Hausner, Lucrezia; Vandenberghe, Rik; Johannsen, Peter; et al. (J Alzheimers Dis, 2017)
BACKGROUND: Performance on episodic, semantic, and working memory tests is impaired in Alzheimer's disease (AD)-type dementia, but it is unclear which type of memory test is most strongly associated with early AD biomarkers in cerebrospinal fluid (CSF), and most useful for monitoring disease progression. OBJECTIVE: To examine the association between amyloid-β 1-42 (Aβ42) and tau in CSF with performance on different memory domains at baseline, and how these CSF markers are related with memory decline. METHODS: We included 263 individuals with normal cognition, mild cognitive impairment, AD-type dementia, and non-AD dementia from the European EDAR study. Assessment included CSF Aβ42 and t-tau analyses with INNO-BIA AlzBio3 Luminex assay, the CERAD wordlist learning and delayed recall, animal fluency test, and the CANTAB Paired Associates Learning (PAL) and Spatial Working Memory tasks. Follow-up assessments were performed within 3 years after baseline. RESULTS: At baseline, decreased CSF Aβ42 correlated most strongly with the PAL total errors adjusted and the wordlist delayed recall and increased CSF t-tau with the wordlist delayed recall. Over time, decreased CSF Aβ42 was associated with decline on the wordlist learning, whereas increased CSF t-tau were associated with decline in scores on the wordlist learning, wordlist delayed recall, and animal fluency. Associations were independent of baseline diagnosis. CONCLUSION: Tests assessing episodic verbal and visuospatial memory are most useful for detection of AD pathology. Tests for episodic verbal memory and semantic memory are most useful for tracking memory decline.

Meta-Analysis of Parkinson's Disease and Alzheimer's Disease Revealed Commonly Impaired Pathways and Dysregulation of NRF2-Dependent Genes. - Wang, Qian; Li, Wen-Xing; Dai, Shao-Xing; Guo, Yi-Cheng; Han, Fei-Fei; Zheng, Jun-Juan; Li, Gong-Hua; Huang, Jing-Fei (J Alzheimers Dis, 2017)
Many lines of evidence suggest that Parkinson's disease (PD) and Alzheimer's disease (AD) have common characteristics, such as mitochondrial dysfunction and oxidative stress. As the underlying molecular mechanisms are unclear, we perform a meta-analysis with 9 microarray datasets of PD studies and 7 of AD studies to explore it. Functional enrichment analysis revealed that PD and AD both showed dysfunction in the synaptic vesicle cycle, GABAergic synapses, phagosomes, oxidative phosphorylation, and TCA cycle pathways, and AD had more enriched genes. Comparing the differentially expressed genes between AD and PD, we identified 54 common genes shared by more than six tissues. Among them, 31 downregulated genes contained the antioxidant response element (ARE) consensus sequence bound by NRF2. NRF2 is a transcription factor, which protects cells against oxidative stress through coordinated upregulation of ARE-driven genes. To our surprise, although NRF2 was upregulated, its target genes were all downregulated. Further exploration found that MAFF was upregulated in all tissues and significantly negatively correlated with the 31 NRF2-dependent genes in diseased conditions. Previous studies have demonstrated over-expressed small MAFs can form homodimers and act as transcriptional repressors. Therefore, MAFF might play an important role in dysfunction of NRF2 regulatory network in PD and AD.

Metabolic and Growth Rate Alterations in Lymphoblastic Cell Lines Discriminate Between Down Syndrome and Alzheimer's Disease. - Coskun, Pinar; Helguera, Pablo; Nemati, Zahra; Bohannan, Ryan C; Thomas, Jean; Samuel, Schriner E; Argueta, Jocelyn; Doran, Eric; Wallace, Douglas C; Lott, Ira T; Busciglio, Jorge (J Alzheimers Dis, 2017)
BACKGROUND: Deficits in mitochondrial function and oxidative stress play pivotal roles in Down syndrome (DS) and Alzheimer's disease (AD) and these alterations in mitochondria occur systemically in both conditions. OBJECTIVE: We hypothesized that peripheral cells of elder subjects with DS exhibit disease-specific and dementia-specific metabolic features. To test this, we performed a comprehensive analysis of energy metabolism in lymphoblastic-cell-lines (LCLs) derived from subjects belonging to four groups: DS-with-dementia (DSAD), DS-without-dementia (DS), sporadic AD, and age-matched controls. METHODS: LCLs were studied under regular or minimal feeding regimes with galactose or glucose as primary carbohydrate sources. We assessed metabolism under glycolysis or oxidative phosphorylation by quantifying cell viability, oxidative stress, ATP levels, mitochondrial membrane potential (MMP), mitochondrial calcium uptake, and autophagy. RESULTS: DS and DSAD LCLs showed slower growth rates under minimal feeding. DS LCLs mainly dependent on mitochondrial respiration exhibited significantly slower growth and higher levels of oxidative stress compared to other groups. While ATP levels (under mitochondrial inhibitors) and mitochondrial calcium uptake were significantly reduced in DSAD and AD cells, MMP was decreased in DS, DSAD, and AD LCLs. Finally, DS LCLs showed markedly reduced levels of the autophagy marker LC3-II, underscoring the close association between metabolic dysfunction and impaired autophagy in DS. CONCLUSION: There are significant mitochondrial functional changes in LCLs derived from DS, DSAD, and AD patients. Several parameters analyzed were consistently different between DS, DSAD, and AD lines suggesting that metabolic indicators between LCL groups may be utilized as biomarkers of disease progression and/or treatment outcomes.

A Metal-Free Method for Producing MRI Contrast at Amyloid-β. - Hilt, Silvia; Tang, Tang; Walton, Jeffrey H; Budamagunta, Madhu; Maezawa, Izumi; Kálai, Tamás; Hideg, Kálmán; Singh, Vikrant; Wulff, Heike; Gong, Qizhi; Jin, Lee-Way; Louie, Angelique; et al. (J Alzheimers Dis, 2017)
Alzheimer's disease (AD) is characterized by depositions of the amyloid-β (Aβ) peptide in the brain. The disease process develops over decades, with substantial neurological loss occurring before a clinical diagnosis of dementia can be rendered. It is therefore imperative to develop methods that permit early detection and monitoring of disease progression. In addition, the multifactorial pathogenesis of AD has identified several potential avenues for AD intervention. Thus, evaluation of therapeutic candidates over lengthy trial periods also demands a practical, noninvasive method for measuring Aβ in the brain. Magnetic resonance imaging (MRI) is the obvious choice for such measurements, but contrast enhancement for Aβ has only been achieved using Gd(III)-based agents. There is great interest in gadolinium-free methods to image the brain. In this study, we provide the first demonstration that a nitroxide-based small-molecule produces MRI contrast in brain specimens with elevated levels of Aβ. The molecule is comprised of a  fluorene (a molecule with high affinity for Aβ) and a nitroxide spin label (a paramagnetic MRI contrast species). Labeling of brain specimens with the spin-labeled fluorene produces negative contrast in samples from AD model mice whereas no negative contrast is seen in specimens harvested from wild-type mice. Injection of spin-labeled fluorene into live mice resulted in good brain penetration, with the compound able to generate contrast 24-h post injection. These results provide a proof of concept method that can be used for early, noninvasive, gadolinium-free detection of amyloid plaques by MRI.

Methionine Sulfoxide Reductase-B3 (MsrB3) Protein Associates with Synaptic Vesicles and its Expression Changes in the Hippocampi of Alzheimer's Disease Patients. - Adams, Stephanie L; Benayoun, Laurent; Tilton, Kathy; Chavez, Olivia R; Himali, Jayandra J; Blusztajn, Jan Krzysztof; Seshadri, Sudha; Delalle, Ivana (J Alzheimers Dis, 2017)
Genome-wide association studies (GWAS) identified susceptibility loci associated with decreased hippocampal volume, and found hippocampal subfield-specific effects at MSRB3 (methionine sulfoxide reductase-B3). The MSRB3 locus was also linked to increased risk for late onset Alzheimer's disease (AD). In this study, we uncovered novel sites of MsrB3 expression in CA pyramidal layer and arteriolar walls by using automated immunohistochemistry on hippocampal sections from 23 individuals accompanied by neuropathology reports and clinical dementia rating scores. Controls, cognitively intact subjects with no hippocampal neurofibrillary tangles, exhibited MsrB3 signal as distinct but rare puncta in CA1 pyramidal neuronal somata. In CA3, however, MsrB3-immunoreactivity was strongest in the neuropil of the pyramidal layer. These patterns were replicated in rodent hippocampi where ultrastructural and immunohistofluorescence analysis revealed MsrB3 signal associated with synaptic vesicles and colocalized with mossy fiber terminals. In AD subjects, the number of CA1 pyramidal neurons with frequent, rather than rare, MsrB3-immunoreactive somatic puncta increased in comparison to controls. This change in CA1 phenotype correlated with the occurrence of AD pathological hallmarks. Moreover, the intensity of MsrB3 signal in the neuropil of CA3 pyramidal layer correlated with the signal pattern in neurons of CA1 pyramidal layer that was characteristic of cognitively intact individuals. Finally, MsrB3 signal in the arteriolar walls in the hippocampal white matter decreased in AD patients. This characterization of GWAS-implicated MSRB3 protein expression in human hippocampus suggests that patterns of neuronal and vascular MsrB3 protein expression reflect or underlie pathology associated with AD.

Methylene Blue (Tetramethylthionine Chloride) Influences the Mobility of Adult Neural Stem Cells: A Potentially Novel Therapeutic Mechanism of a Therapeutic Approach in the Treatment of Alzheimer's Disease. - van der Ven, Amelie T; Pape, Julius C; Hermann, Dirk; Schloesser, Robert; Genius, Just; Fischer, Nadine; Mößner, Rainald; Scherbaum, Norbert; Wiltfang, Jens; Rujescu, Dan; Benninghoff, Jens (J Alzheimers Dis, 2017)
An interest in neurogenesis in the adult human brain as a relevant and targetable process has emerged as a potential treatment option for Alzheimer's disease and other neurodegenerative conditions. The aim of this study was to investigate the effects of tetramethylthionine chloride (methylene blue, MB) on properties of adult murine neural stem cells. Based on recent clinical studies, MB has increasingly been discussed as a potential treatment for Alzheimer's disease. While no differences in the proliferative capacity were identified, a general potential of MB in modulating the migratory capacity of adult neural stem cells was indicated in a cell mobility assay. To our knowledge, this is the first time that MB could be associated with neural mobility. The results of this study add insight to the spectrum of features of MB within the central nervous system and may be helpful for understanding the molecular mechanisms underlying a potential therapeutic effect of MB.

MicroRNAs in Human Cerebrospinal Fluid as Biomarkers for Alzheimer's Disease. - Lusardi, Theresa A; Phillips, Jay I; Wiedrick, Jack T; Harrington, Christina A; Lind, Babett; Lapidus, Jodi A; Quinn, Joseph F; Saugstad, Julie A (J Alzheimers Dis, 2017)
BACKGROUND: Currently available biomarkers of Alzheimer's disease (AD) include cerebrospinal fluid (CSF) protein analysis and amyloid PET imaging, each of which has limitations. The discovery of extracellular microRNAs (miRNAs) in CSF raises the possibility that miRNA may serve as novel biomarkers of AD. OBJECTIVE: Investigate miRNAs in CSF obtained from living donors as biomarkers for AD. METHODS: We profiled miRNAs in CSF from 50 AD patients and 49 controls using TaqMan® arrays. Replicate studies performed on a subset of 32 of the original CSF samples verified 20 high confidence miRNAs. Stringent data analysis using a four-step statistical selection process including log-rank and receiver operating characteristic (ROC) tests, followed by random forest tests, identified 16 additional miRNAs that discriminate AD from controls. Multimarker modeling evaluated linear combinations of these miRNAs via best-subsets logistic regression, and computed area under the ROC (AUC) curve ascertained classification performance. The influence of ApoE genotype on miRNA biomarker performance was also evaluated. RESULTS: We discovered 36 miRNAs that discriminate AD from control CSF. 20 of these retested in replicate studies verified differential expression between AD and controls. Stringent statistical analysis also identified these 20 miRNAs, and 16 additional miRNA candidates. Top-performing linear combinations of 3 and 4 miRNAs have AUC of 0.80-0.82. Addition of ApoE genotype to the model improved performance, i.e., AUC of 3 miRNA plus ApoE4 improves to 0.84. CONCLUSIONS: CSF miRNAs can discriminate AD from controls. Combining miRNAs improves sensitivity and specificity of biomarker performance, and adding ApoE genotype improves classification.

The Mild Behavioral Impairment Checklist (MBI-C): A Rating Scale for Neuropsychiatric Symptoms in Pre-Dementia Populations. - Ismail, Zahinoor; Agüera-Ortiz, Luis; Brodaty, Henry; Cieslak, Alicja; Cummings, Jeffrey; Fischer, Corinne E; Gauthier, Serge; Geda, Yonas E; Herrmann, Nathan; Kanji, Jamila; Lanctôt, Krista L; Miller, David S; et al. (J Alzheimers Dis, 2017)
BACKGROUND: Mild behavioral impairment (MBI) is a construct that describes the emergence at ≥50 years of age of sustained and impactful neuropsychiatric symptoms (NPS), as a precursor to cognitive decline and dementia. MBI describes NPS of any severity, which are not captured by traditional psychiatric nosology, persist for at least 6 months, and occur in advance of or in concert with mild cognitive impairment. While the detection and description of MBI has been operationalized in the International Society to Advance Alzheimer's Research and Treatment - Alzheimer's Association (ISTAART-AA) research diagnostic criteria, there is no instrument that accurately reflects MBI as described. OBJECTIVE: To develop an instrument based on ISTAART-AA MBI criteria. METHODS: Eighteen subject matter experts participated in development using a modified Delphi process. An iterative process ensured items reflected the five MBI domains of 1) decreased motivation; 2) emotional dysregulation; 3) impulse dyscontrol; 4) social inappropriateness; and 5) abnormal perception or thought content. Instrument language was developed a priori to pertain to non-demented functionally independent older adults. RESULTS: We present the Mild Behavioral Impairment Checklist (MBI-C), a 34-item instrument, which can easily be completed by a patient, close informant, or clinician. CONCLUSION: The MBI-C provides the first measure specifically developed to assess the MBI construct as explicitly described in the criteria. Its utility lies in MBI case detection, and monitoring the emergence of MBI symptoms and domains over time. Studies are required to determine the prognostic value of MBI for dementia development, and for predicting different dementia subtypes.

Mitochondrial Repair Effects of Oxygen Treatment on Alzheimer's Disease Model Mice Revealed by Quantitative Proteomics. - Wang, Hao; Hong, Xiaoyu; Wang, Yong (J Alzheimers Dis, 2017)
Mitochondrial dysfunction plays a pivotal role in Alzheimer's disease (AD), even before signs of AD pathology are evident. Our previous research has shown that oxygen treatment can improve cognitive function in AD model mice. To address whether oxygen treatment is beneficial to mitochondrial biology, we analyzed differential expressions of hippocampal mitochondrial proteins in AD model mice given supplementary oxygen. Numerous respiratory chain, Kreb's cycle, and glycolysis proteins were upregulated significantly after oxygen treatment, suggesting that oxygen therapy can alleviate mitochondrial damage. Furthermore, the treatment was associated with decreased expressions of some AD biomarkers, suggesting oxygen treatment to be a potential therapy for AD.

Moderate Physical Activity is Associated with Cerebral Glucose Metabolism in Adults at Risk for Alzheimer's Disease. - Dougherty, Ryan J; Schultz, Stephanie A; Kirby, Taylor K; Boots, Elizabeth A; Oh, Jennifer M; Edwards, Dorothy; Gallagher, Catherine L; Carlsson, Cynthia M; Bendlin, Barbara B; Asthana, Sanjay; Sager, Mark A; Hermann, Bruce P; et al. (J Alzheimers Dis, 2017)
The objective of this study was to investigate the relationship between accelerometer-measured physical activity (PA) and glucose metabolism in asymptomatic late-middle-aged adults. Ninety-three cognitively healthy late-middle-aged adults from the Wisconsin Registry for Alzheimer's Prevention participated in this cross-sectional study. They underwent 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) imaging and wore an accelerometer (ActiGraph GT3X+) to measure free-living PA. Accelerometer data yielded measures of light (LPA), moderate (MPA), and vigorous (VPA) intensity PA. FDG-PET images were scaled to the cerebellum and pons, and cerebral glucose metabolic rate was extracted from specific regions of interest (ROIs) known to be hypometabolic in AD, i.e., hippocampus, posterior cingulate, inferior temporal cortex, and angular gyrus. Regression analyses were utilized to examine the association between PA and glucose metabolism, while adjusting for potential confounds. There were associations between MPA and glucose metabolism in all ROIs examined. In contrast, LPA was not associated with glucose uptake in any ROI and VPA was only associated with hippocampal FDG uptake. Secondary analyses did not reveal associations between sedentary time and glucose metabolism in any of the ROIs. Exploratory voxel-wise analysis identified additional regions where MPA was significantly associated with glucose metabolism including the precuneus, supramarginal gyrus, amygdala, and middle frontal gyrus. These findings suggest that the intensity of PA is an important contributor to neuronal function in a late-middle-aged cohort, with MPA being the most salient. Prospective studies are necessary for fully elucidating the link between midlife engagement in PA and later life development of AD.

Modifiable Risk Factors for Prevention of Dementia in Midlife, Late Life and the Oldest-Old: Validation of the LIBRA Index. - Vos, Stephanie J B; van Boxtel, Martin P J; Schiepers, Olga J G; Deckers, Kay; de Vugt, Marjolein; Carrière, Isabelle; Dartigues, Jean-François; Pérès, Karine; Artero, Sylvaine; Ritchie, Karen; Galluzzo, Lucia; Scafato, Emanuele; et al. (J Alzheimers Dis, 2017)
BACKGROUND: Recently, the LIfestyle for BRAin health (LIBRA) index was developed to assess an individual's prevention potential for dementia. OBJECTIVE: We investigated the predictive validity of the LIBRA index for incident dementia in midlife, late life, and the oldest-old. METHODS: 9,387 non-demented individuals were recruited from the European population-based DESCRIPA study. An individual's LIBRA index was calculated solely based on modifiable risk factors: depression, diabetes, physical activity, hypertension, obesity, smoking, hypercholesterolemia, coronary heart disease, and mild/moderate alcohol use. Cox regression was used to test the predictive validity of LIBRA for dementia at follow-up (mean 7.2 y, range 1-16). RESULTS: In midlife (55-69 y, n = 3,256) and late life (70-79 y, n = 4,320), the risk for dementia increased with higher LIBRA scores. Individuals in the intermediate- and high-risk groups had a higher risk of dementia than those in the low-risk group. In the oldest-old (80-97 y, n = 1,811), higher LIBRA scores did not increase the risk for dementia. CONCLUSION: LIBRA might be a useful tool to identify individuals for primary prevention interventions of dementia in midlife, and maybe in late life, but not in the oldest-old.

The Modified Frontal Behavioral Inventory (FBI-mod) for Patients with Frontotemporal Lobar Degeneration, Alzheimer's Disease, and Mild Cognitive Impairment. - Suhonen, Noora-Maria; Hallikainen, Ilona; Hänninen, Tuomo; Jokelainen, Jari; Krüger, Johanna; Hall, Anette; Pikkarainen, Maria; Soininen, Hilkka; Remes, Anne M (J Alzheimers Dis, 2017)
While behavioral symptoms are both early and prevalent features of behavioral variant frontotemporal dementia (bvFTD), they can be present in other types of dementia as well, including Alzheimer's disease (AD) and even mild cognitive impairment (MCI). The Frontal Behavioral Inventory (FBI) was specifically developed to capture the behavioral and personality changes in bvFTD; it has also been modified into a self-administered caregiver questionnaire (FBI-mod). We examined the utility of the FBI-mod in differentiating bvFTD (n = 26), primary progressive aphasia (PPA) (n = 7), AD (n = 53), and MCI (n = 50) patients, and investigated how the FBI-mod may be associated with neuropsychological measures. The bvFTD patients scored significantly higher as compared to all other patient groups on the FBI-mod Total (p < 0.005), Negative (p < 0.005), and Positive (p < 0.01) scores. The cut-off point for the FBI-mod Total score that best discriminated the bvFTD and AD patients in our sample was 16, thus substantially lower than reported for the original FBI. For the bvFTD group, only mild correlations emerged between the FBI-mod and the cognitive measures. However, significant correlations between the FBI-mod and depressive symptoms as measured by the BDI-II were found for bvFTD. This suggests that while behavioral symptoms appear independent from cognitive deficits in bvFTD, they may nevertheless be interrelated with depressive symptoms. We conclude that the FBI-mod is an easily administered behavioral scale that can aid in differential diagnosis of bvFTD and should be used in clinical practice. The FBI-mod may further be considered as an outcome measure in clinical trials.

Modulating the Balance of Synaptic and Extrasynaptic NMDA Receptors Shows Positive Effects against Amyloid-β-Induced Neurotoxicity. - Huang, Yan; Shen, Wei; Su, Jie; Cheng, Bin; Li, Dong; Liu, Gang; Zhou, Wen-Xia; Zhang, Yong-Xiang (J Alzheimers Dis, 2017)
Alzheimer's disease (AD) patients suffer a disturbance in the balance between synaptic (GluN2A, mediating the protective pathway) and extrasynaptic NMDA receptors (NMDARs) (GluN2B, mediating the excitotoxic pathway), and, therefore, restoring the balance of GluN2A and GluN2B should be beneficial for AD. In this study, the GluN2B-selective antagonist, ifenprodil, and the non-selective NMDAR agonist, NMDA, had little effect on amyloid-β (Aβ)-induced long-term potentiation deficits. Enhancing the activity of GluN2A had a protective effect against Aβ, and specific activation of GluN2A and inhibition of GluN2B showed a better protective effect. In Aβ ICV-injected animals, the combination of ifenprodil and D-cycloserine (a co-activator of NMDRs similar to D-serine) led to greater improvement in behavior tests (nest building, novel object recognition, and Morris water maze) than ifenprodil (Morris water maze) or D-cycloserine (nest building) alone. Signal pathway analysis showed that Aβ disturbed the GluN2A/GluN2B-related pathway. The ratio of GluN2A to GluN2B decreased in Aβ-treated animals, and TORC dephosphorylation and ERK1/2 activation, which could be initiated by GluN2A, also decreased in the hippocampal tissues of Aβ-treated animals. As a result, the activation of CREB and the content of brain-derived BDNF decreased. The combination of ifenprodil and D-cycloserine reversed the signal pathway more significantly than ifenprodil or D-cycloserine alone, indicating that Aβ-induced toxicology was mediated both by functionally inhibiting GluN2A and enhancing GluN2B. These results indicate that enhancing synaptic NMDARs and inhibiting extrasynaptic NMDARs concurrently showed protective effects against Aβ-induced neurotoxicity, suggesting that modulation of the balance between GluN2A and GluN2B could be a potential strategy for AD drug development and therapy.
Keywords: Amyloid beta-Peptides; Animals; Antimetabolites; Cycloserine; Disease Models, Animal; Excitatory Amino Acid Antagonists; Excitatory Postsynaptic Potentials; Hippocampus; Locomotion; Male; Maze Learning; N-Methylaspartate; Nesting Behavior; Neurotoxicity Syndromes; Peptide Fragments; Piperidines; Rats; Rats, Wistar; Receptors, N-Methyl-D-Aspartate; Recognition (Psychology); Signal Transduction; Synapses

Modulation of AβPP and GSK3β by Endoplasmic Reticulum Stress and Involvement in Alzheimer's Disease. - Liu, Xin-Jun; Wei, Jun; Shang, Ying-Hui; Huang, Han-Chang; Lao, Feng-Xue (J Alzheimers Dis, 2017)
Alzheimer's disease (AD) is a dementia disease with neuronal loss and synaptic impairment. This impairment is caused, at least partly, by the generation of two main AD hallmarks, namely the hyperphosphorylated tau protein comprising neurofibrillary tangles and senile plaques containing amyloid-β (Aβ) peptides. The amyloid-β protein precursor (AβPP) and glycogen synthase kinase-3β (GSK3β) are two main proteins associated with AD and are closely correlated with these hallmarks. Recently, both of the proteins were reported to be modulated by endoplasmic reticulum stress (ERS) and are involved in the pathogenesis of AD. The mechanism of ERS plus the modulation of AβPP processing and GSK3β activity by ERS in AD are summarized and explored in this review.

Mortality Risk after Diagnosis of Early-Onset Alzheimer's Disease versus Late-Onset Alzheimer's Disease: A Propensity Score Matching Analysis. - Chang, Ki Jung; Hong, Chang Hyung; Lee, Kang Soo; Kang, Dae Ryong; Lee, Jeong Dong; Choi, Seong Hye; Kim, Seong Yoon; Na, Duk L; Seo, Sang Won; Kim, Do-Kwan; Lee, Yunhwan; Chung, Young Ki; et al. (J Alzheimers Dis, 2017)
BACKGROUND/OBJECTIVE: We aimed to compare the risk of mortality in patients with early-onset Alzheimer's disease (EOAD) versus those with late-onset AD (LOAD) using a large number of study subjects. We applied propensity score matching (PSM) to minimize confounding biases in the comparison between EOAD and LOAD. METHODS: We obtained data from elderly Korean subjects with AD (n = 3,611) at baseline from the CREDOS cohort study, which was conducted from November 2005 to July 2013. We conducted PSM to reduce the bias due to confounding variables related to survival in patients with AD. The risks of mortality associated with EOAD and LOAD were evaluated by Cox proportional hazard analyses, controlling for relevant covariates. RESULTS: After propensity score matching, 312 subjects with EOAD and 624 subjects with LOAD were selected for further analysis. The Cox proportional hazard analysis showed that patients with EOAD are at a greater risk for mortality compared to those with LOAD (Hazard Ratio: 2.01, 95% CI: 1.01-4.00, p-value: 0.04) when controlling for the direct effect of aging on mortality. The results did not change after adjusting for age at diagnosis, general cognitive function, nutritional factor related to body mass index, and physical disability using activities of daily living. The results support the assumption that EOAD takes a more malignant course than LOAD. CONCLUSIONS: Our results provide support for the idea that EOAD takes a clinical course that is distinct from that of LOAD, especially as pertains to the risk of mortality.

Motor Phenotype in Neurodegenerative Disorders: Gait and Balance Platform Study Design Protocol for the Ontario Neurodegenerative Research Initiative (ONDRI). - Montero-Odasso, Manuel; Pieruccini-Faria, Frederico; Bartha, Robert; Black, Sandra E; Finger, Elizabeth; Freedman, Morris; Greenberg, Barry; Grimes, David A; Hegele, Robert A; Hudson, Christopher; Kleinstiver, Peter W; Lang, Anthony E; et al. (J Alzheimers Dis, 2017)
BACKGROUND: The association of cognitive and motor impairments in Alzheimer's disease and other neurodegenerative diseases is thought to be related to damage in the common brain networks shared by cognitive and cortical motor control processes. These common brain networks play a pivotal role in selecting movements and postural synergies that meet an individual's needs. Pathology in this "highest level" of motor control produces abnormalities of gait and posture referred to as highest-level gait disorders. Impairments in cognition and mobility, including falls, are present in almost all neurodegenerative diseases, suggesting common mechanisms that still need to be unraveled. OBJECTIVE: To identify motor-cognitive profiles across neurodegenerative diseases in a large cohort of patients. METHODS: Cohort study that includes up to 500 participants, followed every year for three years, across five neurodegenerative disease groups: Alzheimer's disease/mild cognitive impairment, frontotemporal degeneration, vascular cognitive impairment, amyotrophic lateral sclerosis, and Parkinson's disease. Gait and balance will be assessed using accelerometers and electronic walkways, evaluated at different levels of cognitive and sensory complexity, using the dual-task paradigm. RESULTS: Comparison of cognitive and motor performances across neurodegenerative groups will allow the identification of motor-cognitive phenotypes through the standardized evaluation of gait and balance characteristics. CONCLUSIONS: As part of the Ontario Neurodegenerative Research Initiative (ONDRI), the gait and balance platform aims to identify motor-cognitive profiles across neurodegenerative diseases. Gait assessment, particularly while dual-tasking, will help dissect the cognitive and motor contribution in mobility and cognitive decline, progression to dementia syndromes, and future adverse outcomes including falls and mortality.

mTORC2 (Rictor) in Alzheimer's Disease and Reversal of Amyloid-β Expression-Induced Insulin Resistance and Toxicity in Rat Primary Cortical Neurons. - Lee, Han-Kyu; Kwon, Bumsup; Lemere, Cynthia A; de la Monte, Suzanne; Itamura, Kyohei; Ha, Austin Y; Querfurth, Henry W (J Alzheimers Dis, 2017)
Mammalian target of rapamycin complex 1 (mTORC1), a nutrient sensor and central controller of cell growth and proliferation, is altered in various models of Alzheimer's disease (AD). Even less studied or understood in AD is mammalian target of rapamycin complex 2 (mTORC2) that influences cellular metabolism, in part through the regulations of Akt/PKB and SGK. Dysregulation of insulin/PI3K/Akt signaling is another important feature of AD pathogenesis. We found that both total mTORC1 and C2 protein levels and individual C1 and C2 enzymatic activities were decreased in human AD brain samples. In two rodent AD models, mTORC1 and C2 activities were also decreased. In a neuronal culture model of AD characterized by accumulation of cellular amyloid-β (Aβ)42, mTORC1 activity was reduced. Autophagic vesicles and markers were correspondingly increased and new protein synthesis was inhibited, consistent with mTORC1 hypofunction. Interestingly, mTORC2 activity in neural culture seemed resistant to the effects of intracellular amyloid. In various cell lines, Aβ expression provoked insulin resistance, characterized by inhibition of stimulated Akt phosphorylation, and an increase in negative mTORC1 regular, p-AMPK, itself a nutrient sensor. Rapamycin decreased phospho-mTOR and to lesser degree p-Rictor. This further suppression of mTORC1 activity protected cells from Aβ-induced toxicity and insulin resistance. More striking, Rictor over-expression fully reversed the Aβ-effects on primary neuronal cultures. Finally, using in vitro assay, Rictor protein addition completely overcame oligomeric Aβ-induced inhibition of the PDK-Akt activation step. We conclude that striking a new balance by restoring mTORC2 abundance and/or inhibition of mTORC1 has therapeutic potential in AD.

A Multi-Cohort Study of ApoE ɛ4 and Amyloid-β Effects on the Hippocampus in Alzheimer's Disease. - Khan, Wasim; Giampietro, Vincent; Banaschewski, Tobias; Barker, Gareth J; Bokde, Arun L W; Büchel, Christian; Conrod, Patricia; Flor, Herta; Frouin, Vincent; Garavan, Hugh; Gowland, Penny; Heinz, Anreas; et al. (J Alzheimers Dis, 2017)
The apolipoprotein E (APOE) gene has been consistently shown to modulate the risk of Alzheimer's disease (AD). Here, using an AD and normal aging dataset primarily consisting of three AD multi-center studies (n = 1,781), we compared the effect of APOE and amyloid-β (Aβ) on baseline hippocampal volumes in AD patients, mild cognitive impairment (MCI) subjects, and healthy controls. A large sample of healthy adolescents (n = 1,387) was also used to compared hippocampal volumes between APOE groups. Subjects had undergone a magnetic resonance imaging (MRI) scan and APOE genotyping. Hippocampal volumes were processed using FreeSurfer. In the AD and normal aging dataset, hippocampal comparisons were performed in each APOE group and in ɛ4 carriers with positron emission tomography Aβ who were dichotomized (Aβ+/Aβ-) using previous cut-offs. We found a linear reduction in hippocampal volumes with ɛ4 carriers possessing the smallest volumes, ɛ3 carriers possessing intermediate volumes, and ɛ2 carriers possessing the largest volumes. Moreover, AD and MCI ɛ4 carriers possessed the smallest hippocampal volumes and control ɛ2 carriers possessed the largest hippocampal volumes. Subjects with both APOE ɛ4 and Aβ+ had the lowest hippocampal volumes when compared to Aβ- ɛ4 carriers, suggesting a synergistic relationship between APOE ɛ4 and Aβ. However, we found no hippocampal volume differences between APOE groups in healthy 14-year-old adolescents. Our findings suggest that the strongest neuroanatomic effect of APOE ɛ4 on the hippocampus is observed in AD and groups most at risk of developing the disease, whereas hippocampi of old and young healthy individuals remain unaffected.

Multimodal Cognitive Enhancement Therapy for Patients with Mild Cognitive Impairment and Mild Dementia: A Multi- Center, Randomized, Controlled, Double-Blind, Crossover Trial. - Han, Ji Won; Lee, Hyeonggon; Hong, Jong Woo; Kim, Kayoung; Kim, Taehyun; Byun, Hye Jin; Ko, Ji Won; Youn, Jong Chul; Ryu, Seung-Ho; Lee, Nam-Jin; Pae, Chi-Un; Kim, Ki Woong (J Alzheimers Dis, 2017)
We developed and evaluated the effect of Multimodal Cognitive Enhancement Therapy (MCET) consisting of cognitive training, cognitive stimulations, reality orientation, physical therapy, reminiscence therapy, and music therapy in combination in older people with mild cognitive impairment (MCI) or mild dementia. This study was a multi-center, double-blind, randomized, placebo-controlled, two-period cross-over study (two 8-week treatment phases separated by a 4-week wash-out period). Sixty-four participants with MCI or dementia whose Clinical Dementia Rating was 0.5 or 1 were randomized to the MCET group or the mock-therapy (placebo) group. Outcomes were measured at baseline, week 9, and week 21. Fifty-five patients completed the study. Mini-Mental State Examination (effect size = 0.47, p = 0.013) and Alzheimer's Disease Assessment Scale-Cognitive Subscale (effect size = 0.35, p = 0.045) scores were significantly improved in the MCET compared with mock-therapy group. Revised Memory and Behavior Problems Checklist frequency (effect size = 0.38, p = 0.046) and self-rated Quality of Life - Alzheimer's Disease (effect size = 0.39, p = 0.047) scores were significantly improved in the MCET compared with mock-therapy. MCET improved cognition, behavior, and quality of life in people with MCI or mild dementia more effectively than conventional cognitive enhancing activities did.

Neuroimaging Feature Terminology: A Controlled Terminology for the Annotation of Brain Imaging Features. - Iyappan, Anandhi; Younesi, Erfan; Redolfi, Alberto; Vrooman, Henri; Khanna, Shashank; Frisoni, Giovanni B; Hofmann-Apitius, Martin (J Alzheimers Dis, 2017)
Ontologies and terminologies are used for interoperability of knowledge and data in a standard manner among interdisciplinary research groups. Existing imaging ontologies capture general aspects of the imaging domain as a whole such as methodological concepts or calibrations of imaging instruments. However, none of the existing ontologies covers the diagnostic features measured by imaging technologies in the context of neurodegenerative diseases. Therefore, the Neuro-Imaging Feature Terminology (NIFT) was developed to organize the knowledge domain of measured brain features in association with neurodegenerative diseases by imaging technologies. The purpose is to identify quantitative imaging biomarkers that can be extracted from multi-modal brain imaging data. This terminology attempts to cover measured features and parameters in brain scans relevant to disease progression. In this paper, we demonstrate the systematic retrieval of measured indices from literature and how the extracted knowledge can be further used for disease modeling that integrates neuroimaging features with molecular processes.

Neuroprotective Effect of TREM-2 in Aging and Alzheimer's Disease Model. - Raha, Animesh Alexander; Henderson, James W; Stott, Simon R W; Vuono, Romina; Foscarin, Simona; Friedland, Robert P; Zaman, Shahid H; Raha-Chowdhury, Ruma (J Alzheimers Dis, 2017)
Neuroinflammation and activation of innate immunity are early events in neurodegenerative diseases including Alzheimer's disease (AD). Recently, a rare mutation in the gene Triggering receptor expressed on myeloid cells 2 (TREM2) has been associated with a substantial increase in the risk of developing late onset AD. To uncover the molecular mechanisms underlying this association, we investigated the RNA and protein expression of TREM2 in APP/PS1 transgenic mice. Our findings suggest that TREM2 not only plays a critical role in inflammation, but is also involved in neuronal cell survival and in neurogenesis. We have shown that TREM2 is a soluble protein transported by macrophages through ventricle walls and choroid plexus, and then enters the brain parenchyma via radial glial cells. TREM2 protein is essential for neuroplasticity and myelination. During the late stages of life, a lack of TREM2 protein may accelerate aging processes and neuronal cell loss and reduce microglial activity, ultimately leading to neuroinflammation. As inflammation plays a major role in neurodegenerative diseases, a lack of TREM2 could be a missing link between immunomodulation and neuroprotection.

Neuropsychiatric Symptoms and Alzheimer's Disease Biomarkers Predict Driving Decline: Brief Report. - Babulal, Ganesh M; Stout, Sarah H; Head, Denise; Holtzman, David M; Fagan, Anne M; Morris, John C; Roe, Catherine M (J Alzheimers Dis, 2017)
We examined whether neuropsychiatric symptoms (NPS) interact with cerebrospinal fluid (CSF) biomarkers (amyloid-β42 [Aβ42], tau, phosphorylated tau181 [ptau181], tau/Aβ42, and ptau181/Aβ42) of Alzheimer's disease pathology to predict driving decline among cognitively-normal older adults (N = 116) aged ≥65. Cox proportional hazards models examined time to receiving a rating of marginal or fail on the driving test. Age, education, and gender were adjusted in the models. Participants with more abnormal CSF (Aβ42, tau/Aβ42, ptau181/Aβ42) and NPS were faster to receive a marginal/fail on the road test compared to those without NPS. NPS interact with abnormal CSF biomarkers to impact driving performance among cognitively-normal older adults.

Neuropsychological Profile in the C9ORF72 Associated Behavioral Variant Frontotemporal Dementia. - Suhonen, Noora-Maria; Haanpää, Ramona M; Korhonen, Ville; Jokelainen, Jari; Pitkäniemi, Anni; Heikkinen, Anna-Leena; Krüger, Johanna; Hartikainen, Päivi; Helisalmi, Seppo; Hiltunen, Mikko; Hänninen, Tuomo; Remes, Anne M (J Alzheimers Dis, 2017)
While the C9ORF72 expansion is a major cause of behavioral variant frontotemporal dementia (bvFTD), little is known of the resultant cognitive profile. Our aim was to characterize the neuropsychological profile of the C9ORF72 associated bvFTD. We contrasted structured neuropsychological assessments of the C9ORF72 expansion carrier bvFTD patients (n = 26) with non-carrier bvFTD patients (n = 47) and those with Alzheimer's disease (AD) (n = 47). As compared to the non-carrier bvFTD patients, the C9ORF72 expansion carriers performed at a higher level in an immediate verbal memory test while showing poorer phonemic verbal fluency. Additionally, the expansion carriers committed more errors in the Stroop test and the Alternating S task relative to the non-carriers. Finally, while the AD patients outperformed both bvFTD patient groups in working memory, their performance was more impaired in episodic memory tasks relative to the bvFTD groups. We conclude that bvFTD patients carrying the C9ORF72 expansion may display more pronounced executive deficits together with less severe verbal memory impairment as compared to their non-carrier bvFTD counterparts. Knowledge of the specific neuropsychological features associated with the C9ORF72 related bvFTD may aid in the early diagnosis of the disease as well as in targeting genetic testing.

Neuropsychological Symptoms in Sporadic Creutzfeldt-Jakob Disease Patients in Germany. - Krasnianski, Anna; Bohling, Geeske T; Heinemann, Uta; Varges, Daniela; Meissner, Bettina; Schulz-Schaeffer, Walter J; Reif, Andreas; Zerr, Inga (J Alzheimers Dis, 2017)
BACKGROUND: The polymorphism at codon 129 of the prion protein gene (PRNP) and the PrPSc types 1 and 2 belong to a molecular classification of sporadic Creutzfeldt-Jakob disease (sCJD) that correlates well with the clinical and neuropathological phenotype of sCJD. OBJECTIVE: The aim of the study was to perform the first detailed evaluation of neuropsychological deficits in a large group of definite sCJD patients with known molecular subtype. METHODS: We analyzed neuropsychological symptoms in a cohort of 248 sCJD patients with known M129 V polymorphism of PRNP and prion protein type. RESULTS: Neuropsychological symptoms were very frequent in our patients (96%) and occurred as early as in the first third of the disease course. Besides amnesia and impaired attention (89% each), frontal lobe syndrome (75%), aphasia (63%), and apraxia (57%) were the most common neuropsychological deficits. There was no statistically significant difference with regard to frequency of neuropsychological symptoms between the subtypes. In MV2 and VV2 patients, the onset of neuropsychological symptoms was significantly later than in all other subtypes. CONCLUSION: We provide the first detailed analysis of neuropsychological symptoms in a large group of sCJD patients with known M129 V genotype and prion protein type. We suggest that the rate of progression of neuropsychological symptoms is subtype-specific. These data may improve the diagnosis in atypical sCJD subtypes.

Neurovascular Specifications in the Alzheimer-Like Brain of Mice Affected by Focal Cerebral Ischemia: Implications for Future Therapies. - Michalski, Dominik; Hofmann, Sarah; Pitsch, Roman; Grosche, Jens; Härtig, Wolfgang (J Alzheimers Dis, 2017)
Alzheimer's disease (AD), the most frequent type of dementia, is a prototypical neurodegenerative disease, but shares with stroke certain common risk factors. Consequently, how vascular pathology may modulate AD pathogenesis has gained scientific attention. Therefore, aside from typical features of AD (e.g., amyloid-β, tau hyperphosphorylation, and cholinergic dysfunction), changes within the 'neurovascular unit' (NVU) are of particular interest. This study focused on cholinergic, choline acetyltransferase (ChAT)-immunopositive, and tyrosine hydroxylase (TH)-containing neurons in association with the vasculature to explore the neurovascular complex of the AD brain affected by stroke. Wild-type and triple-transgenic (3xTg) mice of different ages underwent unilateral permanent focal cerebral ischemia. Histochemical analyses comprised diverse neuronal and vascular NVU components, and markers of AD. Immunofluorescence labeling confirmed the existence of Aβ deposits and phospho-tau together with glial reactions and morphologically altered endothelia, visualized by Solanum tuberosum lectin. Twenty-four hours after ischemia induction, immunoreactivities for ChAT and TH declined in the ischemia-affected striatum and, at least in part, in the ischemic border zone and ipsilateral neocortex. Correlation analyses indicated simultaneous degeneration of neuronal and vascular components. A trend for more severe affection of ChAT was observed in younger as compared with older mice. The present findings suggest complex interactions within the NVU of the AD-like brain affected by ischemia, comprising alterations of the cholinergic system in conjunction with vascular pathology. Hence, it may be worthwhile to explore the impact of a cellular stabilization approach on vascular and glial elements in AD in terms of a potential disease-alleviating strategy.

No Genetic Overlap Between Circulating Iron Levels and Alzheimer's Disease. - Lupton, Michelle K; Benyamin, Beben; Proitsi, Petroula; Nyholt, Dale R; Ferreira, Manuel A; Montgomery, Grant W; Heath, Andrew C; Madden, Pamela A; Medland, Sarah E; Gordon, Scott D; Lovestone, Simon; Tsolaki, Magda; et al. (J Alzheimers Dis, 2017)
Iron deposition in the brain is a prominent feature of Alzheimer's disease (AD). Recently, peripheral iron measures have also been shown to be associated with AD status. However, it is not known whether these associations are causal: do elevated or depleted iron levels throughout life have an effect on AD risk? We evaluate the effects of peripheral iron on AD risk using a genetic profile score approach by testing whether variants affecting iron, transferrin, or ferritin levels selected from GWAS meta-analysis of approximately 24,000 individuals are also associated with AD risk in an independent case-control cohort (n∼10,000). Conversely, we test whether AD risk variants from a GWAS meta-analysis of approximately 54,000 account for any variance in iron measures (n∼9,000). We do not identify a genetic relationship, suggesting that peripheral iron is not causal in the initiation of AD pathology.

Non-Phosphorylated Tau as a Potential Biomarker of Alzheimer's Disease: Analytical and Diagnostic Characterization. - Lewczuk, Piotr; Lelental, Natalia; Lachmann, Ingolf; Holzer, Max; Flach, Katharina; Brandner, Sebastian; Engelborghs, Sebastiaan; Teunissen, Charlotte E; Zetterberg, Henrik; Molinuevo, José Luis; Mroczko, Barbara; Blennow, Kaj; et al. (J Alzheimers Dis, 2017)
BACKGROUND: Virtually nothing is known about a potential diagnostic role of non-phospho-epitopes of Tau (Non-P-Tau) in cerebrospinal fluid (CSF). OBJECTIVE: To establish and analytically and clinically characterize the first assay capable to measure concentrations of Non-P-Tau in human CSF. METHODS: An antibody (1G2) was developed that selectively binds to the Tau molecule non-phosphorylated at the positions T175 and T181, and was used in establishing a sandwich ELISA capable to measure Non-P-Tau in human CSF, following analytical and clinical validation of the method. RESULTS: The 1G2 antibody shows decreasing reactivity to tau peptides containing phosphorylation mainly at positions T175 and T181. Detection limit of the assay is 25 pg/ml; the coefficients of variation (CVs) of the optical densities of the repeated standard curves were between 3.6-15.9%. Median intra-assay imprecision of double measurements was 4.8%; inter-assay imprecision was in the range of 11.2% - 15.3%. Non-P-Tau concentrations are stable in the CSF samples sent to distinct laboratories under ambient temperature; inter-laboratory variation was approximately 30%. The Non-P-Tau CSF concentrations were highly significantly increased in patients with Alzheimer's disease in stage of mild cognitive impairment or dementia (AD/MCI, n = 58, 109.2±32.0 pg/mL) compared to the non-demented Controls (n = 42, 62.1±9.3 pg/mL, p < 0.001). At the cut-off of 78.3 pg/mL, the sensitivity and the specificity were 94.8% and 97.6%, respectively. CONCLUSION: For the first time, an assay is reported to reliably measure concentrations of non-phosphorylated Tau in human CSF.

Novel Blood-Based Biomarkers of Cognition, Stress, and Physical or Cognitive Training in Older Adults at Risk of Dementia: Preliminary Evidence for a Role of BDNF, Irisin, and the Kynurenine Pathway. - Küster, Olivia C; Laptinskaya, Daria; Fissler, Patrick; Schnack, Cathrin; Zügel, Martina; Nold, Verena; Thurm, Franka; Pleiner, Sina; Karabatsiakis, Alexander; von Einem, Björn; Weydt, Patrick; Liesener, André; et al. (J Alzheimers Dis, 2017)
Psychosocial stress and physical, cognitive, and social activity predict the risk of cognitive decline and dementia. The aim of this study was to elucidate brain-derived neurotrophic factor (BDNF), irisin, and the kynurenine pathway (KP) as potential underlying biological correlates. We evaluated associations of irisin and the KP with BDNF in serum and with cognition, stress, and activities. Furthermore, changes in serum concentrations of BDNF, irisin, and KP metabolites were investigated after physical or cognitive training. Forty-seven older adults at risk of dementia were assigned to 10 weeks of physical training, cognitive training, or a wait-list control condition. Previous physical, cognitive, and social activities and stressful life events were recorded; global cognition, episodic memory, and executive functions were assessed. Serum levels of L-kynurenine, kynurenic acid, 3-hydroxykynurenine (3-HK), and quinolinic acid (QUIN) were determined by validated assays based on liquid chromatography coupled to tandem mass spectrometry. BDNF and irisin serum levels were determined with enzyme-linked immunosorbent assays. BDNF and irisin correlated positively with global cognition and episodic memory, while the neurotoxic metabolite QUIN correlated negatively with executive functions. Stressful life events were associated with reduced BDNF and increased 3-HK. 3-HK decreased after cognitive training, while BDNF tended to increase after physical training. This suggests that psychosocial stress as well as cognitive and physical training may impact BDNF serum levels and the KP. Irisin and QUIN may constitute novel serum biomarkers of cognitive impairment, in addition to BDNF. Larger scale trials are needed to replicate and extend these novel findings.

A Novel Method for Direct Assessment of Everyday Competence Among Older Adults. - Czaja, Sara J; Loewenstein, David A; Sabbag, Samir A; Curiel, Rosie E; Crocco, Elizabeth; Harvey, Philip D (J Alzheimers Dis, 2017)
BACKGROUND: Recent findings indicate that impairments in functional performance do occur among individuals diagnosed with mild cognitive impairment (MCI). Most assessment strategies for everyday competence are associated with challenges with reliability, are typically in paper and pencil format, or require in-person administration by a trained professional. OBJECTIVE: This paper reports on a novel technology-based assessment battery of everyday competence that includes ecologically valid simulations of daily activities important to independence. METHODS: The sample included 85 non-cognitively impaired older adults aged 65+ and 62 older adults diagnosed with amnestic MCI (aMCI). Participants completed standard measures of cognitive abilities and the computerized battery of everyday tasks, which included simulations of a doctor's visit; and medication and financial management tasks. RESULTS: The older adults with aMCI performed significantly poorer on all three tasks in the everyday task battery. Performance on these measures were also moderately correlated with standard measures of cognitive abilities and showed good test-retest reliability. CONCLUSIONS: The results show that it is feasible to use a technology-based assessment battery of everyday tasks with both non-cognitively impaired older adults and older adults with MCI. The use of this type of battery can overcome many of the logistic constraints associated with current functional assessment protocols.

Novel Phospho-Tau Monoclonal Antibody Generated Using a Liposomal Vaccine, with Enhanced Recognition of a Conformational Tauopathy Epitope. - Theunis, Clara; Adolfsson, Oskar; Crespo-Biel, Natalia; Piorkowska, Kasia; Pihlgren, Maria; Hickman, David T; Gafner, Valerie; Borghgraef, Peter; Devijver, Herman; Pfeifer, Andrea; Van Leuven, Fred; Muhs, Andreas (J Alzheimers Dis, 2017)
The microtubule-associated protein Tau is an intrinsically unfolded, very soluble neuronal protein. Under still unknown circumstances, Tau protein forms soluble oligomers and insoluble aggregates that are closely linked to the cause and progression of various brain pathologies, including Alzheimer's disease. Previously we reported the development of liposome-based vaccines and their efficacy and safety in preclinical mouse models for tauopathy. Here we report the use of a liposomal vaccine for the generation of a monoclonal antibody with particular characteristics that makes it a valuable tool for fundamental studies as well as a candidate antibody for diagnostic and therapeutic applications. The specificity and affinity of antibody ACI-5400 were characterized by a panel of methods: (i) measuring the selectivity for a specific phospho-Tau epitope known to be associated with tauopathy, (ii) performing a combination of peptide and protein binding assays, (iii) staining of brain sections from mouse preclinical tauopathy models and from human subjects representing six different tauopathies, and (iv) evaluating the selective binding to pathological epitopes on extracts from tauopathy brains in non-denaturing sandwich assays. We conclude that the ACI-5400 antibody binds to protein Tau phosphorylated at S396 and favors a conformation that is typically present in the brain of tauopathy patients, including Alzheimer's disease.

Occupational Attainment as Risk Factor for Progression from Mild Cognitive Impairment to Alzheimer's Disease: A CREDOS Study. - Myung, Woojae; Lee, Chunsoo; Park, Jin Hong; Woo, Sook-Young; Kim, Seonwoo; Kim, Sangha; Chung, Jae Won; Kang, Hyo Shin; Lim, Shinn-Won; Choi, Junbae; Na, Duk L; Kim, Seong Yoon; et al. (J Alzheimers Dis, 2017)
High occupational attainment has been known as a marker of cognitive reserve. Previous studies in the general population have shown that high occupational attainment is associated with reduced risk of Alzheimer's disease (AD). However, few studies have assessed the effect of occupational attainment on the clinical course of mild cognitive impairment (MCI). In this study, we evaluated whether individuals with high occupational attainment show more frequent progression from MCI to AD. Participants (n = 961) with MCI were recruited from a nationwide, hospital-based multi-center cohort, and were followed for up to 60 months (median: 17.64, interquartile range [12.36, 29.28]). We used Cox regression for competing risks to analyze the effect of occupational attainment on development of AD, treating dementia other than AD as a competing risk. Among the 961 individuals with MCI, a total of 280 (29.1%) converted to dementia during the follow-up period. The risk of progression to AD was higher in the individuals with high occupational attainment after controlling for potential confounders (hazard ratio = 1.83, 95% confidence interval = 1.25-2.69, p = 0.002). High occupational attainment in individuals with MCI is an independent risk factor for higher progression rate of MCI to AD. This result suggests that the protective effect of high occupational attainment against cognitive decline disappears in the MCI stage, and that careful assessment of occupational history can yield important clinical information for prognosis in individuals with MCI.

Of Mice and Men: Comparative Analysis of Neuro-Inflammatory Mechanisms in Human and Mouse Using Cause-and-Effect Models. - Kodamullil, Alpha Tom; Iyappan, Anandhi; Karki, Reagon; Madan, Sumit; Younesi, Erfan; Hofmann-Apitius, Martin (J Alzheimers Dis, 2017)
Perturbance in inflammatory pathways have been identified as one of the major factors which leads to neurodegenerative diseases (NDD). Owing to the limited access of human brain tissues and the immense complexity of the brain, animal models, specifically mouse models, play a key role in advancing the NDD field. However, many of these mouse models fail to reproduce the clinical manifestations and end points of the disease. NDD drugs, which passed the efficacy test in mice, were repeatedly not successful in clinical trials. There are numerous studies which are supporting and opposing the applicability of mouse models in neuroinflammation and NDD. In this paper, we assessed to what extend a mouse can mimic the cellular and molecular interactions in humans at a mechanism level. Based on our mechanistic modeling approach, we investigate the failure of a neuroinflammation targeted drug in the late phases of clinical trials based on the comparative analyses between the two species.

Optical Coherence Tomography Reveals Retinal Neuroaxonal Thinning in Frontotemporal Dementia as in Alzheimer's Disease. - Ferrari, Laura; Huang, Su-Chun; Magnani, Giuseppe; Ambrosi, Alessandro; Comi, Giancarlo; Leocani, Letizia (J Alzheimers Dis, 2017)
BACKGROUND: Alzheimer's disease (AD) and frontotemporal dementia (FTD) are leading causes of cognitive decline. Optical coherence tomography (OCT) allows the measurement of thickness of retinal neuroaxonal layers. While in AD and mild cognitive impairment (MCI), retinal nerve fiber layer (RNFL) thinning is frequently reported, less information is available on ganglion cell layer-inner plexiform layer (GCL-IPL). Data on FTD are lacking. OBJECTIVE: To obtain cross-sectional information on RNFL and GCL-IPL thickness among MCI, AD, FTD, and healthy controls (HC), and their correlations with dementia severity. METHODS: Peripapillary OCT scans were obtained in 27 MCI, 39 AD, 17 FTD, 49 HC using high-definition Heidelberg Spectral-domain OCT, with RNFL and GCL-IPL thickness measurement. Statistical analysis tested group effects and correlation with gender, disease duration and severity (Mini-Mental State Examination, MMSE). RESULTS: RNFL showed a significant group effect [F(4,132) = 3.786, p = 0.006], being reduced versus controls in MCI (p = 0.033), moderate AD (p = 0.025), and FTD (p < 0.001), and versus mild AD in FTD (p = 0.042). GCL-IPL showed a significant group effect as well [F(4,121) = 5.104, p < 0.001], with reduction in moderate AD versus HC (p < 0.001), MCI (p = 0.037), and mild AD (p = 0.009); in FTD versus HC (p = 0.002) and mild AD (p = 0.038). In AD, GCL-IPL correlated with MMSE (r = 0.487, p = 0.003), without significant effects of age, gender, or disease duration. CONCLUSION: Retinal neuroaxonal thinning occurs in MCI/AD consistently with previous reports, as well as in FTD. Correlation with disease severity in AD suggests that retinal and brain neurodegeneration may occur in parallel to some extent, and prompts larger studies aimed at providing surrogate endpoints for clinical trials in AD.

Overexpression of Kinesin Superfamily Motor Proteins in Alzheimer's Disease. - Hares, Kelly; Miners, James Scott; Cook, Amelia Jane; Rice, Claire; Scolding, Neil; Love, Seth; Wilkins, Alastair (J Alzheimers Dis, 2017)
Defects in motor protein-mediated neuronal transport mechanisms have been implicated in a number of neurodegenerative disorders but remain relatively little studied in Alzheimer's disease (AD). Our aim in the present study was to assess the expression of the anterograde kinesin superfamily motor proteins KIF5A, KIF1B, and KIF21B, and to examine their relationship to levels of hyperphosphorylated tau, amyloid-β protein precursor (AβPP), and amyloid-β (Aβ) in human brain tissue. We used a combination of qPCR, immunoblotting, and ELISA to perform these analyses in midfrontal cortex from 49 AD and 46 control brains. Expression of KIF5A, KIF1B, and KIF21B at gene and protein level was significantly increased in AD. KIF5A protein expression correlated inversely with the levels of AβPP and soluble Aβ in AD brains. Upregulation of KIFs may be an adaptive response to impaired axonal transport in AD.

Oxygen and Glucose Deprivation Alter Synaptic Distribution of Tau Protein: The Role of Phosphorylation. - Mavroeidi, Panagiota; Mavrofrydi, Olga; Pappa, Elpiniki; Panopoulou, Myrto; Papazafiri, Panagiota; Haralambous, Sylva; Efthimiopoulos, Spiros (J Alzheimers Dis, 2017)
Alterations in tau synaptic distribution are considered to underlie synaptic dysfunction observed in Alzheimer's disease (AD). In the present study, brain blood hypoperfusion was simulated in mouse brain slices, and tau levels and phosphorylation were investigated in total extracts, as well as in postsynaptic density fractions (PSDs) and non-PSDs obtained through differential extraction and centrifugation. Oxygen deprivation (OD) resulted in tau dephosphorylation at several AD-related residues and activation of GSK3β and phosphatase PP2A. On the contrary, glucose deprivation (GD) did not affect total levels of cellular tau or its phosphorylation despite inactivation of GSK3β. However, tau distribution in PSD and non-PSD fractions and the pattern of tau phosphorylation in these compartments is highly complex. In PSDs, tau was increased under GD conditions and decreased under OD conditions. GD resulted in tau dephosphorylation at Ser199, Ser262, and Ser396 while OD resulted in tau hyperphosphorylation at Ser199 and Ser404. In the non-PSD fraction, GD or OD resulted in lower levels of tau, but the phosphorylation status of tau was differentially affected. In GD conditions, tau was found dephosphorylated at Ser199, Thr205, and Ser404 and hyperphosphorylated at Ser262. However, in OD conditions tau was found hyperphosphorylated at Thr205, SerSer356, Ser396, and Ser404. Combined OD and GD resulted in degradation of cellular tau and dephosphorylation of PSD tau at Ser396 and Ser404. These results indicate that oxygen deprivation causes dephosphorylation of tau, while GD and OD differentially affect distribution of total tau and tau phosphorylation variants in neuronal compartments by activating different mechanisms.

Pain Assessment in Dementia: Evaluation of a Point-of-Care Technological Solution. - Atee, Mustafa; Hoti, Kreshnik; Parsons, Richard; Hughes, Jeffery D (J Alzheimers Dis, 2017)
Pain is common among people with moderate to severe dementia, but inability of patients to self-report means it often goes undetected and untreated. We developed the electronic Pain Assessment Tool (ePAT) to address this issue. A point-of-care App, it utilizes facial recognition technology to detect facial micro-expressions indicative of pain. ePAT also records the presence of pain-related behaviors under five additional domains (Voice, Movement, Behavior, Activity, and Body). In this observational study, we assessed the psychometric properties of ePAT compared to the Abbey Pain Scale (APS). Forty aged care residents (70% females) over the age of 60 years, with moderate to severe dementia and a history of pain-related condition(s) were recruited into the study. Three hundred and fifty-three paired pain assessments (either at rest or post-movement) were recorded and analyzed. The ePAT demonstrated excellent concurrent validity (r = 0.882, 95% CI: 0.857-0.903) and good discriminant validity. Inter-rater reliability score was good overall (weighted κ= 0.74, 95% CI: 0.68-0.80) while internal consistency was excellent. ePAT has psychometric properties which make it suitable for use in non-communicative patients with dementia. ePAT also has the advantage of automated facial expression assessment which provides objective and reproducible evidence of the presence of pain.

Pathway-Specific Polygenic Risk Scores as Predictors of Amyloid-β Deposition and Cognitive Function in a Sample at Increased Risk for Alzheimer's Disease. - Darst, Burcu F; Koscik, Rebecca L; Racine, Annie M; Oh, Jennifer M; Krause, Rachel A; Carlsson, Cynthia M; Zetterberg, Henrik; Blennow, Kaj; Christian, Bradley T; Bendlin, Barbara B; Okonkwo, Ozioma C; Hogan, Kirk J; et al. (J Alzheimers Dis, 2017)
Polygenic risk scores (PRSs) have been used to combine the effects of variants with small effects identified by genome-wide association studies. We explore the potential for using pathway-specific PRSs as predictors of early changes in Alzheimer's disease (AD)-related biomarkers and cognitive function. Participants were from the Wisconsin Registry for Alzheimer's Prevention, a longitudinal study of adults who were cognitively asymptomatic at enrollment and enriched for a parental history of AD. Using genes associated with AD in the International Genomics of Alzheimer's Project's meta-analysis, we identified clusters of genes that grouped into pathways involved in amyloid-β (Aβ) deposition and neurodegeneration: Aβ clearance, cholesterol metabolism, and immune response. Weighted pathway-specific and overall PRSs were developed and compared to APOE alone. Mixed models were used to assess whether each PRS was associated with cognition in 1,200 individuals, cerebral Aβ deposition measured using amyloid ligand (Pittsburgh compound B) positron emission imaging in 168 individuals, and cerebrospinal fluid Aβ deposition, neurodegeneration, and tau pathology in 111 individuals, with replication performed in an independent sample. We found that PRSs including APOE appeared to be driven by the inclusion of APOE, suggesting that the pathway-specific PRSs used here were not more predictive than an overall PRS or APOE alone. However, pathway-specific PRSs could prove to be useful as more knowledge is gained on the genetic variants involved in specific biological pathways of AD.

Pazopanib Reduces Phosphorylated Tau Levels and Alters Astrocytes in a Mouse Model of Tauopathy. - Javidnia, Monica; Hebron, Michaeline L; Xin, Yue; Kinney, Nikolas G; Moussa, Charbel E-H (J Alzheimers Dis, 2017)
Hyperphosphorylation and aggregation of tau protein is a critical factor in many neurodegenerative diseases. These diseases are increasing in prevalence, and there are currently no cures. Previous work from our group and others has shown that tyrosine kinase inhibitors (TKIs) can stimulate autophagy, decrease pathological proteins, and improve symptoms in models of neurodegeneration. Here we examined the role of pazopanib in mouse models that express either human mutant P301L tau (TauP301L) or triple mutant amyloid precursor protein (3x-AβPP). The TauP301L mouse expresses P301L tau under the control of a prion promoter in both neurons and astrocytes, reminiscent of some human tauopathies. Pazopanib crosses the blood-brain barrier with no detectable peripheral off-side effects, and decreases p-tau in TauP301L mice. Pazopanib reaches a brain concentration sufficient for inhibition of several tyrosine kinases, including vascular endothelial growth factor receptors (VEGFRs). Further, pazopanib does not affect microglia but reduces astrocyte levels toward nontransgenic controls in TauP301L mice. Pazopanib does not alter amyloid beta levels or astrocytes in 3x-AβPP mice but modulates a number of inflammatory markers (IP-10, MIP-1α, MIP-1β, and RANTES). These data suggest that pazopanib may be involved in p-tau clearance and modulation of astrocytic activity in models of tauopathies.

PCSK9 Promotes oxLDL-Induced PC12 Cell Apoptosis Through the Bcl-2/Bax-Caspase 9/3 Signaling Pathway. - Liu, Lu-Shan; Bai, Xue-Qin; Gao, Ya; Wu, Qi; Ren, Zhong; Li, Qing; Pan, Li-Hong; He, Ni-Ya; Peng, Juan; Tang, Zhi-Han (J Alzheimers Dis, 2017)
BACKGROUND: Hyperlipidemia is a risk factor for neurodegenerative diseases. Proprotein convertase subtilisin / Kexin type 9 (PCSK9) degrades hepatic low-density lipoprotein receptor (LDLR) to regulate lipid metabolism. It is unclear if PCSK9 plays a role in neurodegenerative diseases. OBJECTIVE: This study was designed to determine whether PCSK9 is crucial between hyperlipidemia and Alzheimer's disease. The interrelationship between PCSK9 and neuronal apoptosis was explored in PC12 cells in response to treatment with oxidized low-density lipoprotein (oxLDL). METHODS: Cultured PC12 cells were serum-starved and incubated with different concentrations of oxLDL for 24 h. Intracytoplasmic lipid droplets were observed by oil red O staining. Morphological assessment of apoptotic cells was performed using Hoechst 33258 staining and flow cytometry analysis. The expression of mRNA and protein was detected by reverse-transcription polymerase chain reaction (RT-PCR) and western blot analyses, respectively. Transfection of small interfering RNA (siRNA) into PC12 cells was conducted using HiperFect Transfection Reagent. Concentrations of Aβ40 and Aβ42 were detected by enzyme-linked immunosorbent assay (ELISA) kit. RESULTS: Intracellular lipid content, the number of apoptotic cells, and PCSK9 expression were increased in PC12 cells after oxLDL treatment. Transfection with PCSK9 siRNA reduced the oxLDL-induced apoptosis of PC12 cells. We further confirmed the involvement of Bcl-2/Bax-Caspase (9, 3) signaling pathway in the regulation of PC12 cells apoptosis.β-Secretase 1, another target gene of PCSK9, was downregulated in PC12 cells in response to oxLDL treatment. Aβ40 and Aβ42 contents were also decreased. CONCLUSION: PCSK9 promotes oxLDL-induced PC12 cell apoptosis through the Bcl-2/Bax-Caspase 9/3 signaling pathway.
Keywords: Amyloid beta-Peptides; Analysis of Variance; Animals; Apoptosis; bcl-2-Associated X Protein; Caspases; Culture Media, Serum-Free; Dose-Response Relationship, Drug; Flow Cytometry; Lipid Metabolism; Lipoproteins, LDL; PC12 Cells; Peptide Fragments; Proprotein Convertase 9; Proto-Oncogene Proteins c-bcl-2; Rats; RNA, Messenger; RNA, Small Interfering; Signal Transduction; Transfection

PE859, A Novel Curcumin Derivative, Inhibits Amyloid-β and Tau Aggregation, and Ameliorates Cognitive Dysfunction in Senescence-Accelerated Mouse Prone 8. - Okuda, Michiaki; Fujita, Yuki; Hijikuro, Ichiro; Wada, Mei; Uemura, Takuya; Kobayashi, Yukako; Waku, Tomonori; Tanaka, Naoki; Nishimoto, Takaaki; Izumi, Yasuhiko; Kume, Toshiaki; Akaike, Akinori; et al. (J Alzheimers Dis, 2017)
Aggregation of amyloid-β (Aβ) and tau plays a crucial role in the onset and progression of Alzheimer's disease (AD). Therefore, the inhibition of Aβ and tau aggregation may represent a potential therapeutic target for AD. Herein, we designed and synthesized both Aβ and tau dual aggregation inhibitors based on the structure of curcumin and developed the novel curcumin derivative PE859. In this study, we investigated the inhibitory activity of PE859 on Aβ aggregationin vitro and the therapeutic effects of PE859 on cognitive dysfunction via dual inhibition of Aβ and tau aggregation in vivo. PE859 inhibited Aβ aggregation in vitro and protected cultured cells from Aβ-induced cytotoxicity. Furthermore, PE859 ameliorated cognitive dysfunction and reduced the amount of aggregated Aβ and tau in brains of senescence-accelerated mouse prone 8 (SAMP8). These results warrant consideration of PE859 as a candidate drug for AD.

Pen-2 and Presenilin are Sufficient to Catalyze Notch Processing. - Hu, Chen; Xu, Junjie; Zeng, Linlin; Li, Ting; Cui, Mei-Zhen; Xu, Xuemin (J Alzheimers Dis, 2017)
Presenilin-1 (PS1) or presenilin-2 (PS2), nicastrin (NCT), anterior pharynx-defective 1 (Aph-1), and presenilin enhancer-2 (Pen-2) have been considered the minimal essential subunits required to form an active γ-secretase complex. Besides PS, which has been widely believed to function as the catalytic subunit of the complex, the functional roles of the other subunits in the γ-secretase complex remain debatable. In the current study, we set out to determine the role of Pen-2 in γ-secretase activity. To this end, using knockout cells in combination with siRNA and immunoprecipitation approaches, our results revealed that Pen-2 together with presenilin are sufficient to form a functionally active enzyme to process Notch. Specifically, our data demonstrated that Pen-2 plays a crucial role in substrate binding, a mechanism by which Pen-2 contributes directly to the catalytic mechanism of γ-secretase activity. Our data also suggested that there may be different requirements for components to process AβPP and Notch. This information would be important for therapeutic strategy aimed at inhibition or modulation of γ-secretase activity.

People with Dementia Can Learn Compensatory Movement Maneuvers for the Sit-to-Stand Task: A Randomized Controlled Trial. - Werner, Christian; Wiloth, Stefanie; Lemke, Nele Christin; Kronbach, Florian; Jansen, Carl-Philipp; Oster, Peter; Bauer, Jürgen M; Hauer, Klaus (J Alzheimers Dis, 2017)
BACKGROUND: A complex motor skill highly relevant to mobility in everyday life (e.g., sit-to-stand [STS] transfer) has not yet been addressed in studies on motor learning in people with dementia (PwD). OBJECTIVE: To determine whether a dementia-specific motor learning exercise program enables PwD to learn compensatory STS maneuvers commonly taught in geriatric rehabilitation therapy to enhance patients' STS ability. METHODS: Ninety-seven patients with mild-to-moderate dementia (Mini-Mental State Examination: 21.9±2.9 points) participated in a double-blinded, randomized, placebo-controlled trial with 10-week intervention and 3-month follow-up period. The intervention group (IG, n = 51) underwent a motor learning exercise program on compensatory STS maneuvers specifically designed for PwD. The control group (CG, n = 46) performed a low-intensity motor placebo activity. Primary outcomes were scores of the Assessment of Compensatory Sit-to-stand Maneuvers in People with Dementia (ACSID), which covers the number of recalled and initiated, and of effectively performed compensatory STS maneuvers. Secondary outcomes included temporal and kinematic STS characteristics measured by a body-fixed motion sensor (BFS, DynaPort® Hybrid). RESULTS: The IG significantly improved in all ACSID scores compared to the CG (p < 0.001). Secondary analysis confirmed learning effects for all BFS-based outcomes (p < 0.001-0.006). Learning gains were sustained during follow-up for most outcomes. CONCLUSION: People with mild-to-moderate dementia can learn and retain compensatory STS maneuvers in response to a dementia-specific motor learning exercise program. This is the first study that demonstrated preserved motor learning abilities in PwD by using a motor skill highly relevant to everyday life.

PET Tau and Amyloid-β Burden in Mild Alzheimer's Disease: Divergent Relationship with Age, Cognition, and Cerebrospinal Fluid Biomarkers. - Koychev, Ivan; Gunn, Roger N; Firouzian, Azadeh; Lawson, Jennifer; Zamboni, Giovanna; Ridha, Basil; Sahakian, Barbara J; Rowe, James B; Thomas, Alan; Rochester, Lynn; Ffytche, Dominic; Howard, Robert; et al. (J Alzheimers Dis, 2017)
BACKGROUND: Combining PET amyloid-β (Aβ) and tau imaging may be critical for tracking disease progression in Alzheimer's disease (AD). OBJECTIVE: We sought to characterize the relationship between Aβ and tau ligands as well as with other measures of pathology. METHODS: We conducted a multi-center observational study in early AD (MMSE >20) participants aged 50 to 85 y. The schedule included cognitive assessments (ADAS-Cog) and CSF measurement of Aβ and tau at baseline and 6 months; PET-CT imaging with Aβ ([18F]AV45) and tau ([18F]AV1451) ligands at baseline. RESULTS: 22 participants took part in the study with 20 completing its 6-month duration and 12 having both tau and amyloid PET. The PET biomarker analysis revealed a strong negative correlation between age and tau in multiple regions. Entorhinal cortex tau and age interacted significantly in terms of cognitive change over 6 months which may have been to older participants deteriorating faster despite lower levels of cortical tau. Cortical Aβ associated with entorhinal cortex tau while CSF tau/Aβ ratio correlated strongly with cortical tau but not Aβ. CONCLUSION: The negative relationship between age and cortical tau whereby younger patients with mild AD had relatively greater tau burden is potentially important. It suggests that younger-age onset AD may be primarily driven by tau pathology while AD developing later may depend on a multitude of pathological mechanisms. These data also suggest that PET-tau performs better than PET-amyloid in predicting the best validated AD diagnostic marker- the CSF total tau/Aβ ratio.

Phospho-Tau Accumulation and Structural Alterations of the Golgi Apparatus of Cortical Pyramidal Neurons in the P301S Tauopathy Mouse Model. - Antón-Fernández, Alejandro; Merchán-Rubira, Jesús; Avila, Jesús; Hernández, Félix; DeFelipe, Javier; Muñoz, Alberto (J Alzheimers Dis, 2017)
The Golgi apparatus (GA) is a highly dynamic organelle involved in the processing and sorting of cellular proteins. In Alzheimer's disease (AD), it has been shown to decrease in size and become fragmented in neocortical and hippocampal neuronal subpopulations. This fragmentation and decrease in size of the GA in AD has been related to the accumulation of hyperphosphorylated tau. However, the involvement of other pathological factors associated with the course of the disease, such as the extracellular accumulation of amyloid-β (Aβ) aggregates, cannot be ruled out, since both pathologies are present in AD patients. Here we use the P301S tauopathy mouse model to examine possible alterations of the GA in neurons that overexpress human tau (P301S mutated gene) in neocortical and hippocampal neurons, using double immunofluorescence techniques and confocal microscopy. Quantitative analysis revealed that neurofibrillary tangle (NFT)-bearing neurons had important morphological alterations and reductions in the surface area and volume of the GA compared with NFT-free neurons. Since in this mouse model there are no Aβ aggregates typical of AD, the present findings support the idea that the progressive accumulation of phospho-tau is associated with structural alterations of the GA, and that these changes may occur in the absence of Aβ pathology.

Physical Exercise Moderates the Relationship of Apolipoprotein E (APOE) Genotype and Dementia Risk: A Population-Based Study. - Fenesi, Barbara; Fang, Hanna; Kovacevic, Ana; Oremus, Mark; Raina, Parminder; Heisz, Jennifer J (J Alzheimers Dis, 2017)
Genetics and lifestyle independently determine dementia risk, but the interaction is unclear. We assessed the interactive relationship of apolipoprotein E (APOE) genotype and physical exercise on dementia risk over a 5-year period in 1,646 older adults from the Canadian Study of Health and Aging who were dementia-free at baseline. Physical exercise moderated the relationship between genotype and dementia (p < 0.01). Specifically, for APOE ɛ4 non-carriers, the odds of developing dementia were higher in non-exercisers than exercisers (OR = 1.98, 95% CI = 1.44, 2.71, p < 0.001), whereas, for APOE ɛ4 carriers, the odds of developing dementia were not significantly different between non-exercisers and exercisers (OR = 0.71, 95% CI = 0.46, 1.31, p = 0.34). Given that most individuals are not at genetic risk, physical exercise may be an effective strategy for preventing dementia.

Plasma Amyloid-β Levels, Cerebral Small Vessel Disease, and Cognition: The Rotterdam Study. - Hilal, Saima; Akoudad, Saloua; van Duijn, Cornelia M; Niessen, Wiro J; Verbeek, Marcel M; Vanderstichele, Hugo; Stoops, Erik; Ikram, M Arfan; Vernooij, Meike W (J Alzheimers Dis, 2017)
BACKGROUND: Plasma amyloid-β (Aβ) levels are increasingly studied as a potential, accessible marker of cognitive impairment and dementia. The most common plasma Aβ isoforms, i.e., Aβ1-40 and Aβ1-42 have been linked with risk of Alzheimer's disease. However, it remains under-explored whether plasma Aβ levels including novel Aβ1-38 relate to vascular brain disease and cognition in a preclinical-phase of dementiaObjective:To examine the association of plasma Aβ levels (i.e., Aβ1-38, Aβ1-40, and Aβ1-42) with markers of cerebral small vessel disease (SVD) and cognition in a large population-based setting. METHODS: We analyzed plasma Aβ1 levels in 1201 subjects from two independent cohorts of the Rotterdam Study. Markers of SVD [lacunes, white matter hyperintensity (WMH) volume] were assessed on brain MRI (1.5T). Cognition was assessed by a detailed neuropsychological battery. In each cohort, the association of Aβ levels with SVD and cognition was performed using regression models. Estimates were then pooled across cohorts using inverse variance meta-analysis with fixed effects. RESULTS: Higher levels of plasma Aβ1-38, Aβ1-40, Aβ1-42, and Aβ1-40/ Aβ1-42 ratio were associated with increasing lacunar and microbleeds counts. Moreover, higher levels of Aβ1-40 and Aβ1-40/ Aβ1-42 were significantly associated with larger WMH volumes. With regard to cognition, a higher level of Aβ1-38 Aβ1-40 and Aβ1-40/ Aβ1-42 was related to worse performance on cognitive test specifically in memory domain. CONCLUSION: Higher plasma levels of Aβ levels are associated with subclinical markers of vascular disease and poorer memory. Plasma Aβ levels thus mark the presence of vascular brain pathology.

Plasma Proteomic Profiles of Cerebrospinal Fluid-Defined Alzheimer's Disease Pathology in Older Adults. - Dayon, Loïc; Wojcik, Jérôme; Núñez Galindo, Antonio; Corthésy, John; Cominetti, Ornella; Oikonomidi, Aikaterini; Henry, Hugues; Migliavacca, Eugenia; Bowman, Gene L; Popp, Julius (J Alzheimers Dis, 2017)
BACKGROUND: Cerebrospinal fluid (CSF) biomarkers of the beta-amyloid and microtubule associated protein tau metabolism have proven the capacity to improve classification of subjects developing Alzheimer's disease (AD). The blood plasma proteome was characterized to further elaborate upon the mechanisms involved and identify proteins that may improve classification of older adults developing an AD dementia. OBJECTIVE: Identify and describe plasma protein expressions that best classify subjects with CSF-defined presence of AD pathology and cerebral amyloidosis. METHODS: We performed a cross-sectional analysis of samples collected from community-dwelling elderly with (n = 72) or without (n = 48) cognitive impairment. CSF Aβ1-42, tau, and phosphorylated tau (P-tau181) were measured using ELISA, and mass spectrometry quantified the plasma proteomes. Presence of AD pathology was defined as CSF P-tau181/Aβ1-42 > 0.0779, and presence of amyloidosis was defined as CSF Aβ1-42 < 724 pg/mL. RESULTS: Two hundred and forty-eight plasma proteins were quantified. Plasma proteins did not improve classification of the AD CSF biomarker profile in the whole sample. When the analysis was separately performed in the cognitively impaired individuals, the diagnosis accuracy of AD CSF profile was 88.9% with 19 plasma proteins included. Within the full cohort, there were 16 plasma proteins that improved diagnostic accuracy of cerebral amyloidosis to 92.4%. CONCLUSION: Plasma proteins improved classification accuracy of AD pathology in cognitively-impaired older adults and appeared representative of amyloid pathology. If confirmed, those candidates could serve as valuable blood biomarkers of the preclinical stages of AD or risk of developing AD.

Pleiotropic Effect of Human ApoE4 on Cerebral Ceramide and Saturated Fatty Acid Levels. - den Hoedt, Sandra; Janssen, Carola I F; Astarita, Giuseppe; Piomelli, Daniele; Leijten, Frank P J; Crivelli, Simone M; Verhoeven, Adrie J M; De Vries, Helga E; Walter, Jochen; Martinez-Martinez, Pilar; Sijbrands, Eric J G; Kiliaan, Amanda J; et al. (J Alzheimers Dis, 2017)
BACKGROUND: Apolipoprotein E (ApoE) is known for its role in lipid trafficking and the ɛ4 allele is a risk factor for late onset Alzheimer's disease (AD). Recently, aberrant ceramide and fatty acid (FA) levels have been implicated in AD. OBJECTIVE: To determine the specific effects of human ApoE4 (hE4) on cerebral ceramide and FA content during chow or a high fat/high cholesterol (HFHC) diet. METHODS: Cerebral ceramide and FA profiles were determined by LC-MSMS in 15-month-old female wild-type (WT), ApoE-knockout (E0), and hE4-knockin mice fed chow or a HFHC diet for 3 months. mRNA levels of genes involved in ceramide and FA metabolism were determined by qPCR. RESULTS: Similar to E0, hE4 mice displayed lower cerebral total ceramide, Cer16 : 0, and Cer24 : 1 levels than WT mice on both diets. Akin to WT mice, hE4 mice had lower total and saturated FA levels on chow than E0 mice. The HFHC diet significantly increased total and saturated FA levels in hE4 mice. Chow-fed hE4 mice showed lower mRNA levels of ceramide synthase (CerS) 6, acid sphingomyelinase, and of most ceramide and FA transporters than WT and E0 mice. The HFHC diet downregulated the expression of CerSs in hE4 and WT mice, and of ceramide and FA transporters in WT mice, but not in E0 mice. CONCLUSION: hE4 reduced cerebral ceramide levels to levels observed in E0 mice independent of diet. The HFHC diet increased cerebral FA levels in hE4 mice. This was associated with alterations in the expression of ceramide and FA transporters specifically in hE4 mice.

Potentially Inappropriate Medication in Community-Dwelling Primary Care Patients who were Screened Positive for Dementia. - Wucherer, Diana; Eichler, Tilly; Hertel, Johannes; Kilimann, Ingo; Richter, Steffen; Michalowsky, Bernhard; Thyrian, Jochen René; Teipel, Stefan; Hoffmann, Wolfgang (J Alzheimers Dis, 2017)
BACKGROUND: Potentially inappropriate medication (PIM) in older people is a risk factor for adverse drug effects. This risk is even higher in older people with dementia (PWD). OBJECTIVE: Our study aimed to determine (1) the prevalence of PIM among primary care patients who were screened positive for dementia and (2) the sociodemographic and clinical variables associated with the use of PIM. METHODS: DelpHi-MV (Dementia: life- and person-centered help in Mecklenburg-Western Pomerania) is a general practitioner-based, cluster-randomized, controlled intervention study to implement and evaluate an innovative concept of collaborative dementia care management in Germany. The comprehensive baseline assessment includes a home medication review. The present analyses are based on the data from 448 study participants (age 70+, DemTect <9). PIMs were identified using the list of Potentially Inappropriate Medications in the Elderly (Priscus). RESULTS: (1) A total of 99 study participants (22%) received at least one PIM. The highest prevalence was found for antidepressants, benzodiazepines, and analgetics. The most frequently prescribed PIMs were amitriptyline, etoricoxib, and doxazosin. (2) Use of a PIM was significantly associated with a diagnosis of a mental or behavioral disorder. CONCLUSIONS: The prescription rate of PIMs for community-dwelling PWD was comparable with the rates found for the general population of older people in Germany (20-29%). Antidepressants with anticholinergic properties and long-acting benzodiazepines were the most prescribed PIMs, despite having an unfavorable benefit-risk ratio. This high prevalence of PIM prescriptions in a vulnerable population of PWD indicates that standard care for dementia should include careful medication review and management.

Preclinical Amyloid-β and Axonal Degeneration Pathology in Delirium. - Idland, Ane-Victoria; Wyller, Torgeir Bruun; Støen, Randi; Eri, Lars Magne; Frihagen, Frede; Ræder, Johan; Chaudhry, Farrukh Abbas; Hansson, Oskar; Zetterberg, Henrik; Blennow, Kaj; Bogdanovic, Nenad; Brækhus, Anne; et al. (J Alzheimers Dis, 2017)
BACKGROUND: The clinical relevance of brain β-amyloidosis in older adults without dementia is not established. As delirium and dementia are strongly related, studies on patients with delirium may give pathophysiological clues. OBJECTIVE: To determine whether the Alzheimer's disease (AD) cerebrospinal fluid (CSF) biomarkers amyloid-β 1-42 (Aβ42), total tau (T-tau), and phosphorylated tau (P-tau) are associated with delirium in hip fracture patients with and without dementia. METHODS: CSF was collected in conjunction to spinal anesthesia in 129 patients. Delirium was assessed using the Confusion Assessment Method once daily in all patients, both pre- and postoperatively. The diagnosis of dementia at admission was based upon clinical consensus. CSF levels of Aβ42, T-tau, and P-tau were analyzed. RESULTS: In patients without dementia, we found lower CSF Aβ42 levels (median, 310 ng/L versus 489 ng/L, p = 0.006), higher T-tau levels (median, 505 ng/L versus 351 ng/L, p = 0.02), but no change in P-tau in patients who developed delirium (n = 16) compared to those who remained lucid (n = 49). Delirious patients also had lower ratios of Aβ42 to T-tau (p < 0.001) and P-tau (p = 0.001) relative to those without delirium. CSF Aβ42 and T-tau remained significantly associated with delirium status in adjusted analyses. In patients with dementia, CSF biomarker levels did not differ between those with (n = 54) and without delirium (n = 10). CONCLUSION: The reduction in CSF Aβ42, indicating β-amyloidosis, and increase in T-tau, indicating neurodegeneration, in hip fracture patients without dementia developing delirium indicates that preclinical AD brain pathology is clinically relevant and possibly plays a role in delirium pathophysiology.

Precuneus Failures in Subjects of the PSEN1 E280A Family at Risk of Developing Alzheimer's Disease Detected Using Quantitative Electroencephalography. - Ochoa, John Fredy; Alonso, Joan Francesc; Duque, Jon Edinson; Tobón, Carlos Andrés; Baena, Ana; Lopera, Francisco; Mañanas, Miguel Angel; Hernández, Alher Mauricio (J Alzheimers Dis, 2017)
BACKGROUND: Presenilin-1 (PSEN1) mutations are the most common cause of familial early onset Alzheimer's disease (AD). The PSEN1 E280A (E280A) mutation has an autosomal dominant inheritance and is involved in the production of amyloid-β. The largest family group of carriers with E280A mutation is found in Antioquia, Colombia. The study of mutation carriers provides a unique opportunity to identify brain changes in stages previous to AD. Electroencephalography (EEG) is a low cost and minimally invasiveness technique that enables the following of brain changes in AD. OBJECTIVE: To examine how previous reported differences in EEG for Theta and Alpha-2 rhythms in E280A subjects are related to specific regions in cortex and could be tracked across different ages. METHODS: EEG signals were acquired during resting state from non-carriers and carriers, asymptomatic and symptomatic subjects from E280A kindred from Antioquia, Colombia. Independent component analysis (ICA) and inverse solution methods were used to locate brain regions related to differences in Theta and Alpha-2 bands. RESULTS: ICA identified two components, mainly related to the Precuneus, where the differences in Theta and Alpha-2 exist simultaneously at asymptomatic and symptomatic stages. When the ratio between Theta and Alpha-2 is used, significant correlations exist with age and a composite cognitive scale. CONCLUSION: Theta and Alpha-2 rhythms are altered in E280A subjects. The alterations are possible to track at Precuneus regions using EEG, ICA, and inverse solution methods.

Predicting Development of Amyotrophic Lateral Sclerosis in Frontotemporal Dementia. - Van Langenhove, Tim; Piguet, Olivier; Burrell, James R; Leyton, Cristian; Foxe, David; Abela, Melissa; Bartley, Lauren; Kim, Woojin S; Jary, Eve; Huang, Yue; Dobson-Stone, Carol; Kwok, John B; et al. (J Alzheimers Dis, 2017)
BACKGROUND: A proportion of patients with frontotemporal dementia (FTD) also develop amyotrophic lateral sclerosis (ALS). OBJECTIVE: We aimed to establish the risk of developing ALS in patients presenting with FTD and to identify the relevant clinical variables associated with progression from FTD to FTD-ALS. METHODS: Of 218 consecutive patients with FTD, 10.1% had a dual FTD-ALS diagnosis at presentation. The remaining 152 FTD patients with follow-up of at least 12 months were included in the present study. We calculated the rate of progression to FTD-ALS and compared the baseline characteristics of FTD patients who developed ALS to those who did not develop ALS. RESULTS: Five percent of FTD patients developed ALS. The incidence rate of ALS was 6.7/100 patient-years in patients with FTD symptoms since 1 year, which declined with duration of FTD symptoms. No FTD patients developed ALS after 5 years. Five out of 8 FTD patients who developed ALS had presented with a mixed behavioral variant FTD and progressive non-fluent aphasia (bvFTD+PNFA) phenotype, 2 with bvFTD, and 1 with PNFA. Progression to FTD-ALS was significantly more frequent in patients with bvFTD+PNFA compared to those without this phenotype (p < 0.0001, OR 38.3, 95% CI: 7.3 to 199.2), and in FTD patients who carried the C9orf72 repeat expansion compared to those without the repeat expansion (p = 0.02, OR 8.0, 95% CI: 1.7 to 38.6). CONCLUSIONS: FTD patients with a mixed bvFTD+PNFA phenotype and with a C9orf72 repeat expansion should be closely monitored for the possible development of ALS. The risk of developing ALS in FTD appears to decline with the duration of FTD symptoms.

Prediction Model of Conversion to Dementia Risk in Subjects with Amnestic Mild Cognitive Impairment: A Longitudinal, Multi-Center Clinic-Based Study. - Jang, Hyemin; Ye, Byoung Seok; Woo, Sookyoung; Kim, Sun Woo; Chin, Juhee; Choi, Seong Hye; Jeong, Jee Hyang; Yoon, Soo Jin; Yoon, Bora; Park, Kyung Won; Hong, Yun Jeong; Kim, Hee Jin; et al. (J Alzheimers Dis, 2017)
BACKGROUND: Patients with amnestic mild cognitive impairment (aMCI) have an increased risk of dementia. However, conversion rate varies. Therefore, predicting the dementia conversion in these patients is important. OBJECTIVE: We aimed to develop a nomogram to predict dementia conversion in aMCI subjects using neuropsychological profiles. METHODS: A total of 338 aMCI patients from two hospital-based cohorts were used in analysis. All patients were classified into 1) verbal, visual, or both, 2) early or late, and 3) single or multiple-domain aMCI according to the modality, severity of memory dysfunction, and multiplicity of involved cognitive domains, respectively. Patients were followed up, and conversion to dementia within 3 years was defined as the primary outcome. Our patients were divided into a training data set and a validation data set. The associations of potential covariates with outcome were tested, and nomogram was constructed by logistic regression model. We also developed another model with APOE data, which included 242 patients. RESULTS: In logistic regression models, both modalities compared with visual only (OR 4.44, 95% CI 1.83-10.75, p = 0.001), late compared to early (OR 2.59, 95% CI 1.17-5.72, p = 0.019), and multiple compared to single domain (OR 3.51, 95% CI 1.62-7.60, p = 0.002) aMCI were significantly associated with dementia conversion within 3 years. A nomogram incorporating these clinical variables was constructed on the training data set and validated on the validation data set. Both nomograms with and without APOE data showed good prediction performance (c-statistics ≥ 0.75). CONCLUSIONS: This study showed that several neuropsychological profiles of aMCI are significantly associated with imminent dementia conversion, and a nomogram incorporating these clinical subtypes is simple and useful to help to predict disease progression.

Prevalence, Risk Factors, and Complaints Screening Tool Exploration of Subjective Cognitive Decline in a Large Cohort of the Chinese Population. - Hao, Lixiao; Wang, Xiaoni; Zhang, Ling; Xing, Yue; Guo, Qihao; Hu, Xiaochen; Mu, Bin; Chen, Yili; Chen, Guanqun; Cao, Jing; Zhi, Xiaodong; Liu, Jiaojiao; et al. (J Alzheimers Dis, 2017)
BACKGROUND: Substantial studies have reported the prevalence and the affecting factors of subjective cognitive decline (SCD). The complaints screening scale has also been used for probing. However, little is known in China. OBJECTIVE: To investigate the prevalence and risk factors of SCD, and explore an SCD complaints screening scale in China. METHODS: Stratified cluster random sampling was conducted. 2,689 residents aged 60-80 years completed questionnaire 1. 814 residents were included for clinical and neuropsychological evaluations. Two standards were used to make the diagnosis of mild cognitive impairment (MCI) and SCD, and a preliminary screening rate comparison was carried out. Finally, we assessed the risk factors of SCD and the correlation between the SCD-questionnaire 9 (SCD-Q9) and the Auditory Verbal Learning Test-Long Delay Free Recall (AVLT-LR). RESULTS: 1) Standard 1 (ADNI2): the prevalence of SCD was 18.8% (95% CI = 14.7-22.9%) and zero conformed to six criteria (SCD plus). 2) Standard 2 (Jak/Bondi): the prevalence of SCD was 14.4% (95% CI = 10.7-18.1%). 3) Standard 1 had a relatively higher "false" positive rate, whereas Standard 2 had higher "false" negative rate. 4) Age, low education, fewer close friends, and daily drinking were independent risk factors for SCD progressing to MCI. 5) Total points of SCD-Q9 were negatively correlated to the value of AVLT-LR. CONCLUSIONS: The prevalence of SCD is high in the ShunYi District in Beijing, China. Age, low education, less social support, and daily drinking are independent risk factors. The brief SCD-Q9 can be used as a reference.

Protein Phosphorylation is a Key Mechanism in Alzheimer's Disease. - Oliveira, Joana; Costa, Márcio; de Almeida, Maria Soares Cachide; da Cruz E Silva, Odete A B; Henriques, Ana Gabriela (J Alzheimers Dis, 2017)
Altered protein phosphorylation states of several proteins are closely associated with Alzheimer's disease (AD). Among these are the amyloid-β protein precursor (AβPP) and the tau protein. In fact, altered protein phosphorylation states already provide strong biomarkers for AD diagnosis, as is the case with hyperphosphorylated tau. It follows that modulating signaling cascades provides an attractive avenue for exploring novel therapeutic strategies. This review focuses on some of the major protein kinases and protein phosphatases relevant to AD. Of particular relevance, posttranslational modifications dynamically regulate protein activity, subcellular localization, and stability. Protein phosphorylation states can mediate complex formation as well as regulate protein function, and this is important for cellular physiology but can likewise contribute to the development of neuropathological conditions. Furthermore, applying a system approach provides a more comprehensive understanding of the signaling events associated with AD and highlights possible convergence points that may contribute to the different AD pathological hallmarks.

Psychotropic Polypharmacy in Patients with Dementia: Prevalence and Predictors. - Nørgaard, Ane; Jensen-Dahm, Christina; Gasse, Christiane; Hansen, Elsebet Steno; Waldemar, Gunhild (J Alzheimers Dis, 2017)
BACKGROUND: Antipsychotics and other psychotropics are frequently used to treat neuropsychiatric symptoms in patients with dementia, even though the evidence for effect is limited. Concerns have been raised about the safety of antipsychotics, but concomitant use of multiple psychotropic drug classes (psychotropic polypharmacy) may also pose a risk for patients. OBJECTIVE: To investigate the prevalence and predictors associated with use of psychotropic polypharmacy in patients with dementia. METHODS: A population-based study using nationwide registers. Patients with dementia were identified among all Danish residents ≥65 years on January 1, 2012. Data on prescriptions and comorbidity was included in the analysis. Overlapping prescriptions for different psychotropic drug classes were used to determine psychotropic polypharmacy. A multivariable logistic regression analysis was conducted to evaluate factors independently associated with the prescription of other psychotropic drug classes among patients already using antipsychotics. RESULTS: Among all patients registered with dementia (34,553), 25.3% (8,728) used ≥2 psychotropic drugs. Among patients treated with antipsychotics 75.8% (5,403) used at least one other psychotropic drug during the antipsychotic treatment period. Nursing home residency, number of non-psychotropic medications used in 2011, and prior psychiatric diagnosis were associated with psychotropic polypharmacy among antipsychotic drug users. The most frequent combination of psychotropic drugs was antipsychotics and antidepressants. CONCLUSION: Concomitant use of psychotropic drugs was frequent in dementia patients. Patients living in nursing homes had the highest risk of receiving a combination of antipsychotics and other psychotropic drugs. Concomitant use of psychotropics may cause adverse events, and potential consequences for patients' safety call for further investigation.

Pupillary Responses as a Biomarker of Early Risk for Alzheimer's Disease. - Granholm, Eric L; Panizzon, Matthew S; Elman, Jeremy A; Jak, Amy J; Hauger, Richard L; Bondi, Mark W; Lyons, Michael J; Franz, Carol E; Kremen, William S (J Alzheimers Dis, 2017)
Task-evoked pupillary responses may be a psychophysiological biomarker of early risk for mild cognitive impairment (MCI) and Alzheimer's disease (AD). Pupil dilation during cognitive tasks reflects cognitive effort until compensatory capacity is surpassed and performance declines are manifest, and reflects activation in the locus coeruleus, where degenerative changes have been found in the earliest stages of AD. We recorded pupillary responses during digit span recall in 918 participants ages 56-66. Despite normal performance, amnestic single-domain MCI (S-MCI) participants showed greater pupil dilation than non-amnestic S-MCI and cognitively normal (CN) participants at lower cognitive loads. Multi-domain MCI (M-MCI) participants failed to modulate effort across cognitive loads and showed poorer performance. Pupillary responses differentiated MCI and CN groups. Amnestic S-MCI participants required compensatory effort to maintain performance, consistent with increased risk for decline. Greater effort in CN individuals might indicate risk for MCI. Results are consistent with dysfunction in locus coeruleus-linked brain systems. This brief task shows promise as a biomarker for early MCI and AD risk prediction.

Quantitative Comparison of Dense-Core Amyloid Plaque Accumulation in Amyloid-β Protein Precursor Transgenic Mice. - Liu, Peng; Reichl, John H; Rao, Eshaan R; McNellis, Brittany M; Huang, Eric S; Hemmy, Laura S; Forster, Colleen L; Kuskowski, Michael A; Borchelt, David R; Vassar, Robert; Ashe, Karen H; Zahs, Kathleen R (J Alzheimers Dis, 2017)
There exist several dozen lines of transgenic mice that express human amyloid-β protein precursor (AβPP) with Alzheimer's disease (AD)-linked mutations. AβPP transgenic mouse lines differ in the types and amounts of Aβ that they generate and in their spatiotemporal patterns of expression of Aβ assemblies, providing a toolkit to study Aβ amyloidosis and the influence of Aβ aggregation on brain function. More complete quantitative descriptions of the types of Aβ assemblies present in transgenic mice and in humans during disease progression should add to our understanding of how Aβ toxicity in mice relates to the pathogenesis of AD. Here, we provide a direct quantitative comparison of amyloid plaque burdens and plaque sizes in four lines of AβPP transgenic mice. We measured the fraction of cortex and hippocampus occupied by dense-core plaques, visualized by staining with Thioflavin S, in mice from young adulthood through advanced age. We found that the plaque burdens among the transgenic lines varied by an order of magnitude: at 15 months of age, the oldest age studied, the median cortical plaque burden in 5XFAD mice was already ∼4.5 times that of 21-month-old Tg2576 mice and ∼15 times that of 21-24-month-old rTg9191 mice. Plaque-size distributions changed across the lifespan in a line- and region-dependent manner. We also compared the dense-core plaque burdens in the mice to those measured in a set of pathologically-confirmed AD cases from the Nun Study. Cortical plaque burdens in Tg2576, APPSwePS1ΔE9, and 5XFAD mice eventually far exceeded those measured in the human cohort.

Quantitative Erythrocyte Omega-3 EPA Plus DHA Levels are Related to Higher Regional Cerebral Blood Flow on Brain SPECT. - Amen, Daniel G; Harris, William S; Kidd, Parris M; Meysami, Somayeh; Raji, Cyrus A (J Alzheimers Dis, 2017)
BACKGROUND: The interrelationships between omega-3 fatty acids status, brain perfusion, and cognition are not well understood. OBJECTIVE: To evaluate if SPECT brain imaging of cerebral perfusion and cognition varies as a function of omega-3 fatty acid levels. METHODS: A random sample of 166 study participants was drawn from a psychiatric referral clinical for which erythrocyte quantification of omega-3 eicosapentaenoic acid (EPA) plus docosahexaenoic acid (DHA) (the Omega-3 Index) was available. Quantitative brain SPECT was done on 128 regions based on a standard anatomical Atlas Persons with erythrocyte EPA+DHA concentrations were dichotomized based on membership in top 50th percentile versus bottom 50th percentile categories. Two-sample t-tests were done to identify statistically significant differences in perfusion between the percentile groups. Partial correlations were modeled between EPA+DHA concentration and SPECT regions. Neurocognitive status was assessed using computerized testing (WebNeuro) and was separately correlated to cerebral perfusion on brain SPECT imaging and omega-3 EPA+DHA levels. RESULTS: Partial correlation analyses showed statistically significant relationships between higher omega-3 levels and cerebral perfusion were in the right parahippocampal gyrus (r = 0.20, p = 0.03), right precuneus (r = 0.20, p = 0.03), and vermis subregion 6 (p = 0.21, p = 0.03). Omega-3 Index levels separately correlated to the feeling subsection of the WebNeuro (r = 0.25, p = 0.01). CONCLUSION: Quantitative omega-3 EPA+DHA erythrocyte concentrations are independently correlated with brain perfusion on SPECT imaging and neurocognitive tests. These results have implications for the role of omega-3 fatty acids toward contributing to cognitive reserve.

Raman Spectrometric Detection Methods for Early and Non-Invasive Diagnosis of Alzheimer's Disease. - Huang, Chia-Chi; Isidoro, Ciro (J Alzheimers Dis, 2017)
The continuous increasing rate of patients suffering of Alzheimer's disease (AD) worldwide requires the adoption of novel techniques for non-invasive early diagnosis and monitoring of the disease. Here we review the various Raman spectroscopic techniques, including Fourier Transform-Raman spectroscopy, surface-enhanced Raman scattering spectroscopy, coherent anti-Stokes Raman scattering spectroscopy, and confocal Raman microspectroscopy, that could be used for the diagnosis of AD. These techniques have shown the potential to detect AD biomarkers, such as the amyloid-β peptide and the tau protein, or the neurotransmitters involved in the disease (e.g., Glutamate and γ-Aminobutyric acid), or the typical structural alterations in specific brain areas. The possibility to detect the specific biomarkers in liquid biopsies and to obtain high resolution 3D microscope images of the affected area make the Raman spectroscopy a valuable ally in the early diagnosis and monitoring of AD.

Rare Genetic Variant in SORL1 May Increase Penetrance of Alzheimer's Disease in a Family with Several Generations of APOE-ɛ4 Homozygosity. - Louwersheimer, Eva; Cohn-Hokke, Petra E; Pijnenburg, Yolande A L; Weiss, Marjan M; Sistermans, Erik A; Rozemuller, Annemieke J; Hulsman, Marc; van Swieten, John C; van Duijn, Cock M; Barkhof, Frederik; Koene, Teddy; Scheltens, Philip; et al. (J Alzheimers Dis, 2017)
BACKGROUND: The major genetic risk factor for late onset Alzheimer's disease (AD) is the APOE-ɛ4 allele. However, APOE-ɛ4 homozygosity is not fully penetrant, suggesting co-occurrence of additional genetic variants. OBJECTIVE: To identify genetic factors that, next to APOE-ɛ4 homozygosity, contribute to the development of AD. METHODS: We identified a family with nine AD patients spanning four generations, with an inheritance pattern suggestive of autosomal dominant AD, with no variants in PSEN1, PSEN2, or APP. We collected DNA from four affected and seven unaffected family members and performed exome sequencing on DNA from three affected and one unaffected family members. RESULTS: All affected family members were homozygous for the APOE-ɛ4 allele. Statistical analysis revealed that AD onset in this family was significantly earlier than could be expected based on APOE genotype and gender. Next to APOE-ɛ4 homozygosity, we found that all four affected family members carried a rare variant in the VPS10 domain of the SORL1 gene, associated with AβPP processing and AD risk. Furthermore, three of four affected family members carried a rare variant in the TSHZ3 gene, also associated with AβPP processing. Affected family members presented between 61 and 74 years, with variable presence of microbleeds/cerebral amyloid angiopathy and electroencephalographic abnormalities. CONCLUSION: We hypothesize that next to APOE-ɛ4 homozygosity, impaired SORL1 protein function, and possibly impaired TSHZ3 function, further disturbed Aβ processing. The convergence of these genetic factors over several generations might clarify the increased AD penetrance and the autosomal dominant-like inheritance pattern of AD as observed in this family.

Recent Increases in Hippocampal Tau Pathology in the Aging Japanese Population: The Hisayama Study. - Hamasaki, Hideomi; Honda, Hiroyuki; Okamoto, Tsuyoshi; Koyama, Sachiko; Suzuki, Satoshi O; Ohara, Tomoyuki; Ninomiya, Toshiharu; Kiyohara, Yutaka; Iwaki, Toru (J Alzheimers Dis, 2017)
BACKGROUND: The Hisayama study is a prospective cohort study of lifestyle-related diseases that commenced in 1961. Through it, a significant increasing trend in the prevalence of Alzheimer's disease has been observed over the past 18 years. OBJECTIVES: We sought to investigate the increases in brain pathology related to Alzheimer's disease using automated MATLAB morphometric analyses for quantifying tau pathology. METHODS: We examined a series of autopsied cases from Hisayama residents obtained between 1998 and 2003 (group A: 203 cases), and between 2009 and 2014 (group B: 232 cases). We developed custom software in MATLAB to analyze abnormal tau deposits quantitatively. Specimens were immunostained with both anti-amyloid-β-protein and anti-phosphorylated tau antibodies. RESULTS: Both the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) criteria for senile plaques and Braak stage for NFT were higher in group B. Morphometric analyses of the hippocampi also revealed a trend toward increased tau pathology in both men and women over 80 years of age in group B. The increases were also significant when the subjects were examined independently according to high or low CERAD scores and in all levels of AD neuropathologic change according to the National Institute on Aging-Alzheimer's Association guidelines (2012). CONCLUSION: We revealed a recent trend of increased tauopathy in the older people, which is partly independent of amyloid-β pathology.

Recent Progress in Alzheimer's Disease Research, Part 1: Pathology. - Hane, Francis T; Lee, Brenda Y; Leonenko, Zoya (J Alzheimers Dis, 2017)
The field of Alzheimer's disease (AD) research has grown exponentially over the past few decades, especially since the isolation and identification of amyloid-β from postmortem examination of the brains of AD patients. Recently, the Journal of Alzheimer's Disease (JAD) put forth approximately 300 research reports which were deemed to be the most influential research reports in the field of AD since 2010. JAD readers were asked to vote on these most influential reports. In this 3-part review, we review the results of the 300 most influential AD research reports to provide JAD readers with a readily accessible, yet comprehensive review of the state of contemporary research. Notably, this multi-part review identifies the "hottest" fields of AD research providing guidance for both senior investigators as well as investigators new to the field on what is the most pressing fields within AD research. Part 1 of this review covers pathogenesis, both on a molecular and macro scale. Part 2 review genetics and epidemiology, and part 3 covers diagnosis and treatment. This part of the review, pathology, reviews amyloid-β, tau, prions, brain structure, and functional changes with AD and the neuroimmune response of AD.

Recent Progress in Alzheimer's Disease Research, Part 2: Genetics and Epidemiology. - Robinson, Morgan; Lee, Brenda Y; Hane, Francis T (J Alzheimers Dis, 2017)
This is the second part of a three-part review series reviewing the most important advances in Alzheimer's disease (AD) research since 2010. This review covers the latest research on genetics and epidemiology. Epidemiological and genetic studies are revealing important insights into the etiology of, and factors that contribute to AD, as well as areas of priority for research into mechanisms and interventions. The widespread adoption of genome wide association studies has provided compelling evidence of the genetic complexity of AD with genes associated with such diverse physiological function as immunity and lipid metabolism being implicated in AD pathogenesis.

Recent Progress in Alzheimer's Disease Research, Part 3: Diagnosis and Treatment. - Hane, Francis T; Robinson, Morgan; Lee, Brenda Y; Bai, Owen; Leonenko, Zoya; Albert, Mitchell S (J Alzheimers Dis, 2017)
The field of Alzheimer's disease (AD) research has grown exponentially over the past few decades, especially since the isolation and identification of amyloid-β from postmortem examination of the brains of AD patients. Recently, the Journal of Alzheimer's Disease (JAD) put forth approximately 300 research reports which were deemed to be the most influential research reports in the field of AD since 2010. JAD readers were asked to vote on these most influential reports. In this 3-part review, we review the results of the 300 most influential AD research reports to provide JAD readers with a readily accessible, yet comprehensive review of the state of contemporary research. Notably, this multi-part review identifies the "hottest" fields of AD research providing guidance for both senior investigators as well as investigators new to the field on what is the most pressing fields within AD research. Part 1 of this review covers pathogenesis, both on a molecular and macro scale. Part 2 review genetics and epidemiology, and part 3 covers diagnosis and treatment. This part of the review, diagnosis and treatment, reviews the latest diagnostic criteria, biomarkers, imaging, and treatments in AD.
Keywords: Alzheimer Disease; Biomarkers; Biomedical Research; Humans; Neuroimaging

Reduction of RPT6/S8 (a Proteasome Component) and Proteasome Activity in the Cortex is associated with Cognitive Impairment in Lewy Body Dementia. - Alghamdi, Amani; Vallortigara, Julie; Howlett, David R; Broadstock, Martin; Hortobágyi, Tibor; Ballard, Clive; Thomas, Alan J; O'Brien, John T; Aarsland, Dag; Attems, Johannes; Francis, Paul T; Whitfield, David R (J Alzheimers Dis, 2017)
Lewy body dementia is the second most common neurodegenerative dementia and is pathologically characterized by α-synuclein positive cytoplasmic inclusions, with varying amounts of amyloid-β (Aβ) and hyperphosphorylated tau (tau) aggregates in addition to synaptic loss. A dysfunctional ubiquitin proteasome system (UPS), the major proteolytic pathway responsible for the clearance of short lived proteins, may be a mediating factor of disease progression and of the development of α-synuclein aggregates. In the present study, protein expression of a key component of the UPS, the RPT6 subunit of the 19S regulatory complex was determined. Furthermore, the main proteolytic-like (chymotrypsin- and PGPH-) activities have also been analyzed. The middle frontal (Brodmann, BA9), inferior parietal (BA40), and anterior cingulate (BA24) gyrus' cortex were selected as regions of interest from Parkinson's disease dementia (PDD, n = 31), dementia with Lewy bodies (DLB, n = 44), Alzheimer's disease (AD, n = 16), and control (n = 24) brains. Clinical and pathological data available included the MMSE score. DLB, PDD, and AD were characterized by significant reductions of RPT6 (one-way ANOVA, p < 0.001; Bonferroni post hoc test) in prefrontal cortex and parietal cortex compared with controls. Strong associations were observed between RPT6 levels in prefrontal, parietal cortex, and anterior cingulate gyrus and cognitive impairment (p = 0.001, p = 0.001, and p = 0.008, respectively). These findings highlight the involvement of the UPS in Lewy body dementia and indicate that targeting the UPS may have the potential to slow down or reduce the progression of cognitive impairment in DLB and PDD.

Relation of Odor Identification with Alzheimer's Disease Markers in Cerebrospinal Fluid and Cognition. - Reijs, Babette L R; Ramakers, Inez H G B; Elias-Sonnenschein, Lyzel; Teunissen, Charlotte E; Koel-Simmelink, Marleen; Tsolaki, Magda; Wahlund, Lars-Olof; Waldemar, Gunhild; Hausner, Lucrezia; Johannsen, Peter; Vanderstichele, Hugo; Verhey, Frans; et al. (J Alzheimers Dis, 2017)
BACKGROUND: Impaired olfactory function is an early characteristic of Alzheimer's disease (AD), but it remains unclear if odor identification also relates to early markers of AD in cerebrospinal fluid (CSF). OBJECTIVE: To investigate the association between odor identification and amyloid-β 1-42 (Aβ42) and total tau (t-tau) concentrations in CSF. In addition, to examine the relation between odor identification and cognitive function at baseline and at follow-up, and whether these associations are moderated by CSF Aβ42 and t-tau and apolipoprotein E (APOE) genotype. METHODS: We included 160 individuals (40 with normal cognition, 45 with mild cognitive impairment (MCI), 42 with AD-type dementia, and 26 individuals with non-AD dementia) from the EDAR study. Individuals were recruited from six memory clinics across Europe. Odor identification was tested with the brief University of Pennsylvania Smell Identification Test. CSF Aβ42 and t-tau were assessed with INNO-BIA AlzBio3 Luminex assay. Neuropsychological assessment included tests for verbal memory, verbal fluency, attention, executive function, and visuoconstruction. Follow-up was performed within 3 years after baseline. RESULTS: Lower odor identification scores correlated with increased CSF t-tau concentrations and with lower scores on all cognitive measures at baseline independent of diagnostic group. Lower odor identification scores predicted decline on the MMSE in the total group, and decline on wordlist learning and delayed recall in APOE ɛ4 carriers and in individuals with abnormal Aβ42. CONCLUSION: Odor identification impairment may be an indicator of neuronal injury rather than amyloid pathology.

The Relationships Between Components of Metabolic Syndrome and Mild Cognitive Impairment Subtypes: A Cross-Sectional Study of Japanese Older Adults. - Bae, Seongryu; Shimada, Hiroyuki; Lee, Sangyoon; Makizako, Hyuma; Lee, Sungchul; Harada, Kazuhiro; Doi, Takehiko; Tsutsumimoto, Kota; Hotta, Ryo; Nakakubo, Sho; Park, Hyuntae; Suzuki, Takao (J Alzheimers Dis, 2017)
BACKGROUND: The associations between components of metabolic syndrome (MetS) and mild cognitive impairment (MCI) subtypes remain unclear. OBJECTIVE: The study aim was to identify the prevalence of MetS for MCI subtypes and to investigate sex differences in the association between MetS and MCI subtypes in older Japanese adults. METHODS: The study analyzed data from 3,312 men and women aged 70 years or more. MetS was diagnosed according to International Diabetes Federation criteria. Participants completed cognitive tests and were categorized into normal cognition, amnestic MCI (aMCI), and non-amnestic MCI (naMCI). The associations between MetS and its components and MCI subtypes were analyzed using multiple logistic regression. RESULTS: MetS prevalence was greater in participants with naMCI (men: p = 0.030; women: p = 0.040). Participants with naMCI showed higher odds ratios (OR) of MetS (men: 2.45, 95% confidence intervals (CI): 1.13-5.32; women: OR: 1.94, 95% CI: 1.12-3.39) compared with participants with normal cognition. MetS was not associated with aMCI. Analysis of MetS components showed that raised glucose (OR: 1.62, 95% CI: 1.19-2.22) and reduced high-density lipoprotein cholesterol (OR: 1.97, 95% CI: 1.25-3.12) were associated with naMCI in men. In women, raised blood pressure (OR: 1.42, 95% CI: 1.03-1.94) and raised glucose (OR: 1.32, 95% CI: 1.02-1.71) were associated with naMCI. CONCLUSION: MetS was associated only with naMCI regardless of sex, which suggests etiologic differences in MCI subtypes. We also found sex differences in the relationship between naMCI risk and MetS and its components.

Risk of Mortality Associated with Antipsychotic Monotherapy and Polypharmacy Among Community-Dwelling Persons with Alzheimer's Disease. - Koponen, Marjaana; Taipale, Heidi; Lavikainen, Piia; Tanskanen, Antti; Tiihonen, Jari; Tolppanen, Anna-Maija; Ahonen, Riitta; Hartikainen, Sirpa (J Alzheimers Dis, 2017)
We aimed to analyze the risk of non-cancer mortality according to duration of antipsychotic use and to compare the risk associated with polypharmacy and monotherapy among community-dwellers with Alzheimer's disease (AD). The risk of mortality between most frequently used antipsychotic drugs was compared. Data from a nationwide register-based MEDALZ study that included all 70,718 community-dwellers newly diagnosed with AD during 2005-2011 in Finland was utilized. Death, excluding cancer as direct cause of death, was extracted from Causes of Death Register. Incident antipsychotic use was compared with time without antipsychotics with Cox proportional hazard models. Antipsychotic use was associated with an increased risk of mortality (adjusted hazard ratio [aHR] 1.61; 95% Confidence Interval [CI] 1.53-1.70). The absolute difference in mortality rate was 4.58 (95% CI 4.53-4.63) deaths per 100 person-years. The risk of mortality was increased from the first days of use and attenuated gradually but remained increased even after two years of use (aHR 1.30; 95% CI 1.16-1.46). Compared with nonuse, antipsychotic polypharmacy (aHR 2.88; 95% CI 2.38-3.49) was associated with an increased risk of mortality than monotherapy (aHR 1.57; 95% CI 1.49-1.66). Haloperidol was associated with higher risk of mortality (aHR 1.52; 95% CI 1.14-2.02) and quetiapine with lower risk (aHR 0.84; 95% CI 0.75-0.94) compared with risperidone. In conclusion, the findings support current treatment guidelines on having a high threshold for antipsychotic initiation among persons with AD. Antipsychotic polypharmacy and long-term use should be avoided and drug choice should be weighed against risk/benefit evidence.

Role of Suppressor of Cytokine Signaling 3 (SOCS3) in Altering Activated Microglia Phenotype in APPswe/PS1dE9 Mice. - Iwahara, Naotoshi; Hisahara, Shin; Kawamata, Jun; Matsumura, Akihiro; Yokokawa, Kazuki; Saito, Taro; Fujikura, Mai; Manabe, Tatsuo; Suzuki, Hiromi; Matsushita, Takashi; Suzuki, Syuuichirou; Shimohama, Shun (J Alzheimers Dis, 2017)
In response to changes of the central nervous system environment, microglia are capable of acquiring diverse phenotypes for cytotoxic or immune regulation and resolution of injury. Alzheimer's disease (AD) pathology also induces several microglial activations, resulting in production of pro-inflammatory cytokines and reactive oxygen species or clearance of amyloid-β (Aβ) through phagocytosis. We previously demonstrated that microglial activation and increase in oxidative stress started from the middle age in APPswe/PS1dE9 mice, and hypothesized that M1 activation occurs in middle-aged AD mice by Aβ stimulation. In the present study, we analyzed in vivo expressions of pro-inflammatory cytokines (M1 microglial markers), M2 microglial markers, and suppressor of cytokine signaling (SOCS) family, and examined the microglial phenotypic profile in APPswe/PS1dE9 mice. Then we compared the in vitro gene expression patterns of Aβ- and lipopolysaccharide (LPS)-stimulated primary-cultured microglia. Microglia in APPswe/PS1dE9 mice exhibited an M1-like phenotype, expressing tumor necrosis factor α (TNFα) but not interleukin 6 (IL6). Aβ-stimulated primary-cultured microglia also expressed TNFα but not IL6, whereas LPS-stimulated primary-cultured microglia expressed both pro-inflammatory cytokines. Furthermore, both microglia in APPswe/PS1dE9 mice and Aβ-stimulated primary-cultured microglia expressed SOCS3. Reduction of SOCS3 expression in Aβ-challenged primary-cultured microglia resulted in upregulation of IL6 expression. Our findings indicate that SOCS3 suppresses complete polarization to M1 phenotype through blocking IL6 production, and Aβ-challenged primary-cultured microglia replicate the in vivo gene expression pattern of microglia in APPswe/PS1dE9 mice. Aβ may induce the M1-like phenotype through blocking of IL6 by SOCS3.
Keywords: Alzheimer Disease; Amyloid beta-Peptides; Amyloid beta-Protein Precursor; Animals; Brain; Cells, Cultured; Disease Models, Animal; Female; Humans; Interleukin-6; Lipopolysaccharides; Male; Mice, Inbred C57BL; Mice, Transgenic; Microglia; Neurons; Presenilin-1; Suppressor of Cytokine Signaling 3 Protein; Tumor Necrosis Factor-alpha