Stimulation by odor generated by the Maillard reaction promotes longevity through HSF-1 in <i>Caenorhabditis elegans</i>

Olfaction is closely associated with aging, whereas the impact of repeated olfactory stimulation on aging process remains unclear. Therefore, we attempt to examine the anti-aging effects of the odors generated by the Maillard reaction (MR) in C elegans. Chemotaxis assays revealed that nematodes were attracted to MR odors, which was abolished in the odr-3 loss-of-function mutant. These results indicated that the attraction to MR odor is caused by the olfactory system. Among the potent volatile compounds, 2,5-dimethyl-4-hydroxy-3(2H)-furanone attracted the most, which was mediated by AWC neurons. Furthermore, exposure to MR odors extended lifespan, improved motility, and enhanced stress resilience. MR odor upregulated mRNA expressions of ctl-1, ctl-3, hsf-1, hsp-16.2, and hsp-70 in C. elegans. This upregulation was not observed in hsf-1 mutants, suggesting that the longevity-promoting effect depended on HSF-1. Our findings demonstrated that inhalation of odors generated by the MR promotes longevity via olfactory stimulation in C. elegans.