Abstract
Abstract: :
Purpose: Blue light induces apoptosis in human retinal pigment epithelial (RPE) cells. The mechanism of apoptosis is thought to be mediated by A2E. In this study we examined whether blue light can induce apoptosis in human RPE cells in the absence of A2E (RPE cells isolated from fetal eyes). Methods: Pure cultures of human fetal retinal pigment epithelial cells were isolated and cultured. After reaching confluency, cells were exposed to blue light (wave length 430–450 nm) for 3, 5, 7, and 10 days. The rate of RPE cell apoptosis was assessed with Annexin V staining and flow cytometry. Non–exposed (in dark) fetal RPE cells served as control. Results: Blue light induced a significant amount of apoptosis in human fetal RPE cells when compared to the cells in the dark. The amount of apoptosis was significant at all exposure times (3, 5, 7, and 10 days). The rate of apoptosis increased with the increase of blue light exposure. Conclusions: These results indicate that blue light induces apoptosis in human fetal RPE cells. Our findings suggest that other pathways (in addition to A2E) may be involved in blue light induced apoptosis in RPE cells.
Keywords: retinal pigment epithelium • apoptosis/cell death • age-related macular degeneration