Qin Liu, Haiqing Tang
Aging is a complex biological process governed by conserved genetic and metabolic pathways. Increasing evidence has identified the gut microbiota as a critical modulator of host aging and healthspan. The Caenorhabditis elegans model provides a powerful system to elucidate the molecular determinants of this cross-kingdom dialogue. Recent advances in this model organism reveal that gut microbes may regulate aging through two distinct yet convergent mechanisms: (i) the production of small-molecule metabolites that modulate conserved host longevity pathways, and (ii) the presentation of structural components that trigger hormetic defense responses via immune recognition. This review synthesizes these findings, offering a framework for understanding microbial contributions to aging and highlighting potential directions for future research aimed at extending healthspan in higher organisms.