Microbiome and Antiaging Medicine: Gut Bacterial Metabolites and Antiaging

With aging, there is a decrease in basal metabolic rate and immune function, and changes in diet, among other factors, have been reported to reduce the diversity of gut bacteria in the elderly compared to younger individuals and to alter the composition of bacterial species. Furthermore, with the recent advancements in omics analysis, attention is now being focused on gut bacterial metabolites as substantial molecular entities, in addition to the identification of individual species related to host aging control. In fact, from cohort studies and animal experiments, it has become clear that some gut bacterial metabolites fluctuate with aging. For example, it is suggested that the decrease in typical gut bacterial metabolites such as short-chain fatty acids, polyamines, and secondary bile acids with aging is involved in age-related diseases [1]. On the other hand, interesting findings have been reported that these gut bacterial metabolites are at the same level in centenarians as in younger individuals. It is suggested that gut bacterial metabolites are closely related to host aging and age-related diseases, and the control of the production of gut bacterial metabolites is expected to be an important target for the realization of antiaging (Fig. 57.1).