Abstract
Purpose: :
It is known that long term exposure to blue light induces apoptosis in human retinal pigment epithelial (RPE) cells. In this study we evaluated and correlated the effect of short term blue light exposure on apoptosis and vascular endothelial growth factor (VEGF) production in RPE cells.
Methods: :
Pure cultures of human fetal retinal pigment epithelial cells were isolated. Fourth to sixth passage RPE cells were used in the experiments. RPE cells were irradiated with blue light (430–450 nm) for up to 72 hours. The rate of apoptosis was analyzed with Annexin V staining and flow cytometry. The production of VEGF was assessed with ELISA.
Results: :
Blue light exposure decreased the production of VEGF by RPE cells at all time points (when compared to no light exposure). The blue light induced decrease of VEGF production was significant at 48 and 72 hours (P < 0.05). There was no significant increase in blue light induced apoptosis for up to 48 hours. Although there was an increase in blue light induced apoptosis at 72 hours (when compared to no light exposure), this increase was statistically not significant.
Conclusions: :
Blue light induced decrease in the production of VEGF in RPE cells is most likely not secondary to apoptosis. Our findings indicate that blue light exposure may play a role in age related macular degeneration.
Keywords: apoptosis/cell death • retinal pigment epithelium • cytokines/chemokines