Can longer lifespan be associated with gut microbiota involvement in lipid metabolism?

Biological aging is linked to altered body composition and reduced neuroactive steroid hormones like dehydroepiandrosterone sulfate (DHEAS), which can stimulate the GABA signaling pathway via gut microbiota. Our study examined the association of gut microbiota with lifespan in mice through comprehensive analysis of its composition and functional involvement in cholesterol sulfate, a precursor of DHEAS, metabolism. We used 16S rRNA and metagenomic sequencing, followed by metabolic pathway prediction and thin layer chromatography and MALDI-TOF cholesterol sulfate identification. Significant increases in bacteria such as Bacteroides, typical for long-lived and Odoribacter and Colidextribacter, specific for short-lived mice were detected. Furthermore, for males (Rikenella and Alloprevotella) and females (Lactobacillus and Bacteroides), specific bacterial groups emerged as predictors (AUC = 1), highlighting sex-specific patterns. Long-lived mice showed a strong correlation of Bacteroides (0.918) with lipid and steroid hormone metabolism, while a negative correlation of GABAergic synapse with body weight (-0.589). We found that several Bacteroides species harboring the sulfotransferase gene and gene cluster for sulfonate donor synthesis are involved in converting cholesterol to cholesterol sulfate, significantly higher in the feces of long-lived individuals. Overall, we suggest that increased involvement of gut bacteria, mainly Bacteroides spp., in cholesterol sulfate synthesis could ameliorate aging through lipid metabolism.