The microbiome is associated with obesity-related metabolome signature in the process of aging

The roles of specific microbial metabolites in aging remains understudied. Here we examine the microbiome’s contribution to the metabolic profile in aged mice. Fecal samples were collected from 8-week-old (young) and 18-month-old (aged) female Swiss-Webster mice raised conventionally (Conv) or germ free (GF). Bacterial DNA was sequenced and microbiome analysis predormed using QIIME2. Liquid chromatography mass spectrometry was used for untargeted metabolomics on Conv and GF samples.
Significant differences were observed in bacterial composition and predicted functional pathways between young and aged mice. Age-related metabolome variance was greater in Conv than GF mice, highlighting microbial contribution. Moreover, microbiome-associated metabolites, predominantly lipids, were higher in aged mice, with linoleic acid metabolism enriched in this group. Our study underscores a microbiome-dependent component to age-related metabolic changes, particularly in lipid-associated pathways. These findings contribute to the growing body of literature linking gut microbiota with host metabolism in aging.