The Role of L-ascorbate on Cell Death Induced by Ultraviolet A in Ciliary Body Epithelium

ABSTRACT

To evaluate the effect of ascorbate on cell death induced by ultraviolet A, cultured human ciliary body epithelial cells were exposed the UV-A at energy level of 10 and 30J/cm2. Before and after UV-A exposure the experimental group was treated with 250 microgram/ml L-ascorbate while the control group was not. Cell viability was 87.3% in the control group and 97.1% in the experimental group at energy level of 10J/cm2UV-A. Cell viability was decreased to 38.8% in the control group and 73.5% in the experimental group at energy level of 30J/cm2 UV-A. The cells in the experimental group were less affected. This phenomenon was also observed by light microscope. The degree of apoptosis was 4.68% in the control group and 4.11% in the experimental group at the level of 10J/cm2 UV-A. The apoptosis was increased to 11.01% in the control group and 4.16% in the experimental group at the level of 30J/cm2 UV-A. On electron microscope necrosis and apoptosis induced by UV-A were observed in both groups but the degree of cell death was much less in the experimental group. In conclusion, L-ascorbate has a role of decreasing cell death induced by UV-A in ciliary body epithelial cells.