Quercetin inhibits choroidal and retinal angiogenesis in vitro

Background Quercetin is a natural substance found abundantly in grapes, red wine and other food products. In this study, we examined the effect of quercetin on choroidal and retinal angiogenesis in vitro using rhesus choroids-retina endothelial cell line (RF/6A). Methods RF/6A cells were cultured in Dulbecco's Modified Eagle's Medium (DMEM) containing 10% fetal bovine serum. Then cells were treated with different concentrations (from 0 to 100 mu M) of quercetin. The cell proliferation was assessed using choromogenic methylthiazol tetrazolium bromide (MTT) dye after 24, 48 and 72 hours. Cell migration after 24-hour incubation with quercetin was investigated by wound assay. Following exposure to the various concentrations of quercetin for 24 hours, tube formation on matrigel by endothelial cells was also analyzed. Apoptosis was measured by flow cytometry using annexin V-FITC and propidium iodide staining. Results Quercetin inhibits endothelial cell proliferation in a dose-dependent fashion; 10.1%, 42.6% and 65.2% inhibition on treating with 10, 50 and 100 mu M Quercetin respectively. The migration and tube formation of RA/6A cells were also significantly inhibited by quercetin in a dose-dependent manner. Flow cytometric analysis showed that the percentages of apoptotic cells were slightly increased only in 100 mu M quercetin-treated cells. Conclusions Our results show that quercetin inhibits choroidal and retinal angiogenesis in vitro. Further studies are ongoing to evaluate this drug as a potential candidate for the treatment of choroidal or retinal neovascularization.