FIGURE 8.

Capsaicin reduces the UVB-induced ROS generation in cultured fibroblasts. (A) The cultured fibroblasts were pre-treated with capsaicin (Cap, 1 µM) or N-acetyl-l-cysteine (NAC, 5 mg/ml) for 30 min, followed by exposure to UVB irradiation (300 mW/m² for 5 min). Cells were incubated with DCFH-DA (20 µM) and nucleus were stained with DAPI. Images were captured by confocal microscope. (B) The amount of ROS was quantified. (C) The culture fibroblasts were transfected with pARE-Luc constructs, as shown, and then treated with capsaicin (Cap, 1 and 5 µM) or NAC (5 mg/ml) with UVB irradiation (300 mW/m² for 5 min). The protein lysates were collected for luciferase assay. (D) The protein lysates of cells were collected for ELISA assay to measure COL1 content. Values are in percentage of change, or fold of change (X basal), against control, in mean ± SD, n = 5, each with triplicate samples. *, p < 0.05; **, p < 0.01 compared with control (vehicle only).