To identify candidate bacteria associated with aging, we performed fecal microbiota sequencing in young, middle-aged and older adults, and found lower Bifidobacterium adolescentis abundance in older individuals aged ≥60 years. Dietary supplementation of B. adolescentis improved osteoporosis and neurodegeneration in a mouse model of premature aging (Terc−/−) and increased healthspan and lifespan in Drosophila melanogaster and Caenorhabditis elegans. B. adolescentis supplementation increased the activity of the catalase (CAT) enzyme in skeletal muscle and brain tissue from Terc−/− mice, and suppressed cellular senescence in mouse embryonic fibroblasts. Transgenic deletion of catalase (ctl-2) in C. elegans abolished the effects of B. adolescentis on the lifespan and healthspan. B. adolescentis feeding also led to changes in oxidative stress-associated metabolites in Terc−/− mouse feces. These results suggest a role for B. adolescentis in improving the healthspan and lifespan through the regulation of CAT activity and host metabolism.
This study shows that dietary supplementation with B. adolescentis increases the activity of the catalase enzyme and improves the healthspan and lifespan in multiple animal models. Deletion of the catalase enzyme in worms abolished the beneficial effects of the bacterium.