protective effects of lindera coreana on uvb-induced oxidative stress in human hacat keratinocytes

the present study was designed to investigate the protective effect of ethanol extracts from lindera coreana leaves (lce) on uvb-induced oxidative stress in hacat keratinocytes. the hacat cells were pretreated with lce for 24 h and then exposed to uvb (20 mj/cm2) for 2 h. uvb significantly decreased the cell viability (p<0.05). lce did not exhibit significantly cytotoxic effects and increased the viability of the hacat cells in a concentration-dependent manner. to further investigate the protective effects of lce on uvb-induced oxidative stress in hacat cells, the cellular levels of reactive oxygen species (ros), lipid peroxidation and endogenous antioxidant enzymes, including catalase (cat), superoxide dismutase (sod) and glutathione peroxidase (gsh-px), were analyzed. lce decreased the intracellular levels of ros and lipid peroxidation and increased the activity of antioxidant enzymes. these results suggest that lce exerted cytoprotective activity against uvb-induced oxidative stress in hacat cells through the inhibition of lipid peroxidation, reduction of ros levels and stimulation of antioxidant enzymes activities. in addition, lce also decreased the tnf-α, il-1β and il-6 levels in uvb-irradiated hacat cells.