%0 Journal Article %J J Alzheimers Dis %D 2018 %T Predicting and Tracking Short Term Disease Progression in Amnestic Mild Cognitive Impairment Patients with Prodromal Alzheimer's Disease: Structural Brain Biomarkers. %A Marizzoni, Moira %A Ferrari, Clarissa %A Jovicich, Jorge %A Albani, Diego %A Babiloni, Claudio %A Cavaliere, Libera %A Didic, Mira %A Forloni, Gianluigi %A Galluzzi, Samantha %A Hoffmann, Karl-Titus %A Molinuevo, José Luis %A Nobili, Flavio %A Parnetti, Lucilla %A Payoux, Pierre %A Ribaldi, Federica %A Rossini, Paolo Maria %A Schönknecht, Peter %A Soricelli, Andrea %A Hensch, Tilman %A Tsolaki, Magda %A Visser, Pieter Jelle %A Wiltfang, Jens %A Richardson, Jill C %A Bordet, Régis %A Blin, Olivier %A Frisoni, Giovanni B %X

BACKGROUND: Early Alzheimer's disease (AD) detection using cerebrospinal fluid (CSF) biomarkers has been recommended as enrichment strategy for trials involving mild cognitive impairment (MCI) patients.

OBJECTIVE: To model a prodromal AD trial for identifying MRI structural biomarkers to improve subject selection and to be used as surrogate outcomes of disease progression.

METHODS: APOE ɛ4 specific CSF Aβ42/P-tau cut-offs were used to identify MCI with prodromal AD (Aβ42/P-tau positive) in the WP5-PharmaCog (E-ADNI) cohort. Linear mixed models were performed 1) with baseline structural biomarker, time, and biomarker×time interaction as factors to predict longitudinal changes in ADAS-cog13, 2) with Aβ42/P-tau status, time, and Aβ42/P-tau status×time interaction as factors to explain the longitudinal changes in MRI measures, and 3) to compute sample size estimation for a trial implemented with the selected biomarkers.

RESULTS: Only baseline lateral ventricle volume was able to identify a subgroup of prodromal AD patients who declined faster (interaction, p = 0.003). Lateral ventricle volume and medial temporal lobe measures were the biomarkers most sensitive to disease progression (interaction, p≤0.042). Enrichment through ventricular volume reduced the sample size that a clinical trial would require from 13 to 76%, depending on structural outcome variable. The biomarker needing the lowest sample size was the hippocampal subfield GC-ML-DG (granule cells of molecular layer of the dentate gyrus) (n = 82 per arm to demonstrate a 20% atrophy reduction).

CONCLUSION: MRI structural biomarkers can enrich prodromal AD with fast progressors and significantly decrease group size in clinical trials of disease modifying drugs.

%B J Alzheimers Dis %8 2018 Jun 09 %G eng %R 10.3233/JAD-180152 %0 Journal Article %J J Alzheimers Dis %D 2016 %T CHRNA7 Gene and Response to Cholinesterase Inhibitors in an Italian Cohort of Alzheimer's Disease Patients. %A Clarelli, Ferdinando %A Mascia, Elisabetta %A Santangelo, Roberto %A Mazzeo, Salvatore %A Giacalone, Giacomo %A Galimberti, Daniela %A Fusco, Federica %A Zuffi, Marta %A Fenoglio, Chiara %A Franceschi, Massimo %A Scarpini, Elio %A Forloni, Gianluigi %A Magnani, Giuseppe %A Comi, Giancarlo %A Albani, Diego %A Martinelli Boneschi, Filippo %X

Previous studies suggest that genetic variants in CHRNA7, which encodes for the major subunit of the acetylcholine receptor (α7-nAChR), are associated with the clinical response to cholinesterase inhibitors (ChEI) in Alzheimer's disease (AD) patients. We sought to replicate the association of two SNPs in the CHRNA7 gene, rs6494223 and rs8024987, with response to ChEI treatment in an Italian cohort of 169 AD patients, further extending the study to gene-level analysis. None of the tested variants was associated with clinical response. However, rs6494223 showed a consistent effect direction (OR = 1.4; p = 0.17), which after meta-analysis with previous study yielded a significant result (OR = 1.57, p = 0.02, I2 = 0%).

%B J Alzheimers Dis %V 52 %P 1203-8 %8 2016 Apr 16 %G eng %N 4 %1 http://www.ncbi.nlm.nih.gov/pubmed/27104904?dopt=Abstract %R 10.3233/JAD-160074 %0 Journal Article %J J Alzheimers Dis %D 2016 %T Sirtuin 2 Inhibition Improves Cognitive Performance and Acts on Amyloid-β Protein Precursor Processing in Two Alzheimer's Disease Mouse Models. %A Biella, Gloria %A Fusco, Federica %A Nardo, Emanuele %A Bernocchi, Ottavia %A Colombo, Alessio %A Lichtenthaler, Stefan F %A Forloni, Gianluigi %A Albani, Diego %X

The neuropathological hallmarks of Alzheimer's disease (AD) are extracellular plaques built up by the accumulation of the amyloid-β protein precursor (AβPP)-derived peptide β (Aβ), and intracellular tangles of hyperphosphorylated tau protein. Sirtuin 2 (SIRT2) is a member of the sirtuin family, featuring conserved enzymes with deacetylase activity and involved in several cell molecular pathways. We investigated the importance of SIRT2 inhibition in AD. We inhibited SIRT2 by small molecules (AGK-2, AK-7) and examined AβPP metabolism in H4-SW neuroglioma cells overexpressing AβPP and two AD transgenic mouse models (3xTg-AD and APP23). The in vitro studies suggested that the inhibition of SIRT2 reduced Aβ production; in vivo data showed an improvement of cognitive performance in the novel object recognition test, and an effect on AβPP proteolytic processing leading to a reduction of soluble β-AβPP and an increase of soluble α-AβPP protein. In 3xTg-AD mice, we noticed that total tau protein level rose. Overall, our pre-clinical data support a role for SIRT2 inhibition in the improvement of cognitive performance and the modulation of molecular mechanisms relevant for AD, thus deserving attention as possible therapeutic strategy.

%B J Alzheimers Dis %V 53 %P 1193-207 %8 2016 Jun 30 %G eng %N 3 %1 http://www.ncbi.nlm.nih.gov/pubmed/27372638?dopt=Abstract %R 10.3233/JAD-151135