Effect of Long‐Term Dietary Selenium Deprivation and Aging on Gut Microbiota in Short Telomere Mice

Abstract

Gut microbiota represent an important bridge between dietary intake and host metabolism. Selenium (Se) is implicated in aging and age-related degenerations, but the role of gut microbiota in such linkage is not understood. Feces were collected from male Terc-/- premature aging mice at 18 and 24 months of age after being fed a Se-deficient diet or the diet supplemented with Se (0.15 ppm as selenate) since weanling. Metagenomic analyses of PCR-amplified V3-V4 regions of the 16S rRNA gene were performed through a MiSeq platform. Results from a classic multidimensional scaling graph plotted on the basis of Pearson covariance distance matrix demonstrated that the taxonomic composition of gut microbiota changed with age and dietary Se deprivation.The relative abundance of phyla Bacteroidetes was increased while Firmicutes, Actinobacteria and Proteobacteria were decreased as a result of dietary Se deficiency or aging. Analyses of aggregate microbiotic composition at species level based on Shannon diversity index demonstrated that the total microbial diversity was increased while the probiotic Bifidobacterium quantity was decreased by Se deprivation or aging. Taken together, nutritional Se may prevent age-dependent compositional changes of gut microbiota.