Protective Effects of Epigallocatechin Gallate after UV Irradiation in Cultured Human Retinal Pigment Epithelial Cells

Purpose: To evaluate the protective effects of Epigallocatechin gallate (EGCG) against UV irradiation in cultured human retinal pigment epithelial (RPE) cells. Methods: UV irradiation was produced by a UV lamp for 30 seconds with an irradiance of 3.3 mW/cm2. After 5 minutes and 1 hour, we administered different concentrations of EGCG (0, 5, 10, 15, 25, 50, 100 uM). The cell count was determined under a microscope using a counting chamber and the cell activity was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Results: The cell count of cultured human RPE cells after UV irradiation was markedly increased in the EGCG administration group, compared with the non-administrated group. The cell activity of the cultured human RPE cells after UV irradiation was markedly increased in the EGCG administration group and was increased in a dose-dependent way as determined by the MTT assay. Conclusions: The administration of EGCG increased the cell count and the cell activity after UV irradiation in cultured human retinal pigment epithelial cells; this suggests that EGCG provided protection against UV damage in cultured human retinal pigmented epithelial cells.