Latifolin inhibits oxidative stress-induced senescence via upregulation of SIRT1 in human dermal fibroblasts.

Latifolin, a natural flavonoid found in Dalbergia odorifera T. Chen, has been reported to exhibit anti-inflammatory and anticarcinogenic activities in vitro. However, the anti-aging effects of latifolin are unknown. In this study, we selected a model in vitro system, hydrogen peroxide (H₂O₂)-induced senescence in human dermal fibroblasts (HDFs), to examine the protective effects of latifolin against senescence and the detailed molecular mechanisms involved. Latifolin reversed the senescence-like phenotypes of the oxidant-challenged model, including senescence-associated β-galactosidase (SA-β-gal) staining, cell proliferation, and the expression of senescence-related proteins, such as caveolin-1, ac-p53, p21^Cip1/WAF1, p16^Ink4α, pRb, and cyclinD1. We also found that latifolin induced the expression of silent information regulator 1 (SIRT1) in a concentration- and time-dependent manner, and the anti-senescence effect of latifolin was abrogated by SIRT1 inhibition. Latifolin also suppressed the activation of Akt and S6K1 and attenuated the increase in SA-β-gal activity after H₂O₂ exposure. Our results indicate that latifolin exerts protective effects against senescence in HDFs and that induction of SIRT1 and inhibition of the mTOR pathway are key mediators of its anti-aging effects.