Photoprotective Effects of Ice Plant (Mesembryanthemum crystallinum) Callus Extract on Gene Expression of Human Dermal Fibroblast Against UV Exposure

UV exposure is the principal cause of extrinsic photoaging. Antioxidant-related genes (SOD2 and CAT) and collagen-related genes (COL1A1 and TIMP1) were selected for analysis of the mRNA expression in human dermal fibroblasts (CCD-966SK) using qPCR. In this study, UVA-exposed (15 J/cm(2) cells showed decrease in SOD2 , CAT (p < 0 001) and COL1A1 (p < 0 05) gene expression, indicating the decline of antioxidant ability and collagen formation. However, treatment with ice plant callus extract (2 mg/mL, 24 h) before UVA exposure significantly up-regulated SOD2 , CAT , COL1A1 and TIMP1 genes (p < 0 01) by 9.5, 2.7, 1.7 and 3.8 times, respectively, compared with those of the control group, and by 10.2, 4.3 (p < 0 001), 2.1 and 3.8 times, respectively, compared with those of the UVA (only) group. These results demonstrated that ice plant extracts affect both antioxidant- and collagen-related gene expressions, and show positive effects on endogenous antioxidant activity and skin collagen preservation.