Protective Effect of Rutin against Ultraviolet B-induced Cyclooxygenase-2 Expression in Mouse Epidermal Cells

Cyclooxygenase-2 (COX-2) is a major mediator of inflammation and increases carcinogenesis, and it has been reported to play a pivotal role in UVB-mediated skin carcinogenesis. Rutin (3-rhamnosyl-glucosyl quercetin) is found in numerous fruits and vegetables, especially buckwheat. Previous studies indicated that rutin has antioxidant, anti-inflammatory, and anti-carcinogenic activities both in vitro and in vivo. However, the molecular mechanisms underlying these effects of rutin remain unknown. Here, we identified that rutin suppressed UVB-induced COX-2 expression at both the protein and transcriptional levels in JB6 P+ mouse epidermal cells. The activation of nuclear factor (NF)-kappa B and activator protein-1 induced by UVB was dose dependently inhibited by rutin treatment. Western blot data revealed that rutin attenuated UVB-induced phosphorylation of ERK, MKK4, JNK, MKK3, and p38, but not MEK. Overall, these results indicated that rutin may be an effective anti-inflammatory agent in the skin.