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.
Antioxidants/*pharmacology ; Catechin/*analogs & derivatives/pharmacology ; Cell Count ; Cells, Cultured ; Dose-Response Relationship, Radiation ; Humans ; Pigment Epithelium of Eye/cytology/*drug effects/radiation effects ; Radiation Injuries/pathology/*prevention & control ; Radiation-Protective Agents ; Spectrophotometry ; *Ultraviolet Rays