Sesamol modulates ultraviolet-B-induced apoptotic and inflammatory signaling in human skin dermal fibroblasts

Abstract

Aim: Sesamol (SM), a dietary phenolic phytochemical, has been shown to reduce ultraviolet-B (UVB) mediated oxidative damage. The aim of the present study was to investigate the protective mechanism of SM against UVB-induced photoaging, inflammatory and apoptotic signaling in human skin dermal fibroblasts, adult (HDFa) in vitro . Materials and Methods: In this study, we examined the effect of SM on UVB radiation-induced loss of mitochondrial membrane potential (ΔΨm), DNA fragmentation, cell cycle modulation, inflammatory markers [tumor necrosis factor (TNF)-α and nuclear factor (NF)-κB] expression, pro-apoptotic (p53, Bax and caspase-3), and anti-apoptotic marker (Bcl-2) expression in HDFa. We also investigated the effect of SM and/or UVB radiation on matrix metalloproteinase (MMP-2 and MMP-9) activation by gelatin zymograpy in HDFa. Results and Conclusion: SM pretreatment prevented UVB-induced ΔΨm alteration, DNA fragmentation and down-regulated the expressions of apoptotic (p53, Bax and caspase-3) and inflammatory markers (TNF-α and NF-κB) in HDFa. SM also prevented the activation of MMP-2 and MMP-9 in a concentration-dependent manner. Our data indicated the ability of SM to block UVB-induced inflammatory and apoptotic signaling in HDFa. However, further detailed mechanistic approach warrants before claiming this compound for photoprotection.