Influence of APOE Genotype on Whole-Brain Functional Networks in Cognitively Normal Elderly
نویسندگان
چکیده
This study aimed to investigate the influence of apolipoprotein E (APOE) ε4 allele on whole-brain functional networks in cognitively normal (CN) elderly by applying graph theoretical analysis to brain glucose metabolism. Eighty-six CN elderly [28 APOE ε4 carriers (ε4+) and 58 non-carriers (ε4-)] underwent clinical evaluation and resting [(18)F] fluorodeoxyglucose positron emission tomography scan. Whole-brain functional networks were constructed from correlations of the 90 regions of interest using the automated anatomical labeling template, and analyzed using graph theoretical approaches. The overall small-world property seen in ε4- was preserved in ε4+. However, both local clustering and path length were lower in ε4+ compared to ε4-. In terms of the hubs of functional networks, ε4+ showed decreased centrality of the right hippocampus but increased centrality of several brain regions associated with the default mode network compared to ε4-. Our results indicate that genetic vulnerability to Alzheimer's disease may alter whole-brain functional networks even before clinical symptoms appear.
منابع مشابه
Multimodal Investigations in Cognitively Normal Elderly with Different Types of Apolipoprotein E (apoE) Genotype Polymorphism: Brain Volume, Diffusion Anisotropy, and Cerebral Blood Flow MRI Study
Introduction: The apolipoprotein E (apoE) epsilon 4 allele increases a risk of Alzheimer’s disease (AD) [1]. All apoE isoforms inhibit amyloid beta protein aggregation, but apoE4 is less effectively than apoE2 or 3. Numerous studies reported that there was relationship between apoE4 allele load and regionally specific brain cortical atrophy in AD [2-3]. However, there was no study in investigat...
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