Distinct gut microbiota profiles may characterize amyloid beta pathology and mild cognitive impairment

Abstract

AbstractGut microbiome composition has been associated with early preclinical Alzheimer’s disease (AD), as reflected by cerebrospinal fluid (CSF) amyloid beta pathology, and with mild cognitive impairment (MCI). However, the presence of distinct microbiota across different disease stages has not been fully characterized. We profiled gut microbiota in 50 nondemented individuals by 16S ribosomal RNA sequencing and taxonomic profiles were compared between amyloid-based (amyloid-normal vs. amyloid-pathology) and clinically- based (cognitively normal vs. MCI) diagnosis groups using linear models (adjusted for sex, age and diet). Elastic net regression model was used to assess the discriminative performance of microbiota for amyloid-pathology and MCI. Microbial diversity measures did not differ across groups. We identified specific genera associated with amyloid-pathology and MCI such asOxalobacter, MarvinbryantiaandEscherichia-Shigella, mostly linked to inflammation. Distinct genera were found to be unique to amyloid-pathology and MCI. Microbiota was shown to have a fairly good discriminative performance. Overall, we suggest the presence of distinct microbiota in early preclinical stage of AD and MCI, which needs to be further explored.