%0 Journal Article %J J Alzheimers Dis %D 2016 %T Decreased Inter-Hemispheric Functional Connectivity in Cognitively Intact Elderly APOE ɛ4 Carriers: A Preliminary Study. %A Luo, Xiao %A Qiu, Tiantian %A Xu, Xiaojun %A Huang, Peiyu %A Gu, Quanquan %A Shen, Zhujing %A Yu, Xinfeng %A Jia, YunLu %A Guan, Xiaojun %A Song, Ruirui %A Zhang, Minming %K Aged %K Aging %K Apolipoprotein E4 %K Brain %K Brain Mapping %K Female %K Functional Laterality %K Genotyping Techniques %K Heterozygote %K Humans %K Magnetic Resonance Imaging %K Male %K Memory %K Neuropsychological Tests %K Rest %X

The apolipoprotein E (APOE) ɛ4 allele is the best-known genetic risk factor for developing sporadic Alzheimer's disease (AD). According to neuroimaging studies, the APOE ɛ4 allele is associated with localized altered brain function. However, in long-range circuitry, APOE ɛ4 allele-related alterations in functional communication between hemispheres have rarely been directly investigated. We examined the alteration of resting-state functional connectivity (RSFC) between inter-hemispheric homotopic regions in cognitively intact, elderly APOE ɛ4 carriers. The voxel-mirrored homotopic connectivity method was used to assess the inter-hemispheric RSFC. The current study included 13 cognitively intact, elderly APOE ɛ4 carriers (with at least one copy of APOE ɛ4 allele) and 22 well-matched ɛ3 homozygotes. Comparisons between the two groups were conducted, and subsequently, the correlation between the differential inter-hemispheric RSFC and cognitive ability was analyzed. Compared with ɛ3 homozygotes, APOE ɛ4 carriers showed decreased inter-hemispheric RSFC in the bilateral medial temporal lobe (MTL) and orbital frontal cortex (OFC). Moreover, in APOE ɛ4 carriers, the inter-hemispheric RSFC of the MTL correlated with the Wechsler Memory Scale-Logical Memory (WMS-LM) (immediate and delayed performance, r = 0.64, p <  0.05; r = 0.65, p <  0.05, respectively), and the inter-hemispheric RSFC of the OFC correlated with the WMS-LM delayed performance (r = 0.71, p <  0.05). In our study, the presence of the APOE ɛ4 allele was linked with decreased inter-hemispheric RSFC, which was attributed to memory performance in carriers.

%B J Alzheimers Dis %V 50 %P 1137-48 %8 2016 %G eng %N 4 %1 http://www.ncbi.nlm.nih.gov/pubmed/26836191?dopt=Abstract %R 10.3233/JAD-150989