Skin aging is a complex process and involves extrinsic and intrinsic processes with distinct characteristics. Understanding skin aging requires knowledge of the senescence of human dermal fibroblasts (HDFs) and the
biological mechanisms involved in this process. However, the molecular mechanism responsible for the aging of HDFs is still not clear. Therefore, we investigated mechanisms of autophagy,
inflammation, and cellular senescence by Western blotting, immunofluorescence, real-time PCR, and senescence-associated β-
galactosidase (SA-β-gal) staining in senescent HDFs. We found
SRT1720 inhibited the inductions of inflammatory
cytokines and cellular senescence by deacetylating acetyl-NF-κB levels and enhancing levels of autophagy-associated
proteins and
SIRT1 in senescent HDFs. However, the NF-κB activator
prostratin attenuated signals associated with autophagy, such as those of LC3-II and
Beclin-1, but increased inflammatory
cytokine levels and cellular senescence. Notably, the expression levels of
SIRT1 and autophagy-associated
proteins were higher in aged mice administered
SRT1720 than in old mice, and
SRT1720 also decreased levels of acetyl-NF-κB, inflammatory
cytokines, and senescence markers, which was in accord with in vitro results. These findings support that
SRT1720 acts as an anti-aging agent and inhibits the inductions of inflammatory
cytokines and senescence by regulating the
SIRT1/acetyl-NF-κB signaling pathway and activating autophagy in senescent HDFs.