Intravitreal injection of resveratrol inhibits laser-induced murine choroidal neovascularization.

Abstract

To determine the effects of intravitreal resveratrol (RSV) on murine laser-induced choroidal neovascularization (CNV). The toxicity of RSV to choroidal endothelial cell (CEC) was measured using thiazolyl blue tetrazolium bromide (MTT) assay. Effects of RSV on choroidal endothelial cell (CEC) migration were evaluated with a modified Boyden chamber assay, while tube formation was evaluated in a 2-D gel assay. CNV was induced by laser photocoagulation in mice. The effects of intravitreal injection of RSV on CNV development were evaluated by fluorescein angiography (FA), confocal analysis of isolectin B4 labeled choroidal flat mounts, and histologic examination of CNV membranes. Immunostaining was used to analyze the expression and phosphorylation of vascular endothelial growth factor receptor 2 (VEGFR2). No significant cell toxicity was observed in CEC if the concentration of RSV was less than 200 µmol/L (P>0.05). RSV inhibited vascular endothelial growth factor (VEGF)-induced CEC migration (P<0.05) and tube formation (P<0.05) in vitro. Furthermore, intravitreal injection of RSV significantly inhibited laser induced CNV formation in mice. The FA leakage, CNV volume and CNV area analysis revealed that there were 41%, 45%, and 58% reduction in RSV-treated eyes (1.691±0.1032, 178 163±78 623 µm3 and 6508±619.0 µm2, respectively) compared with those in control (2.724±0.08447, 379 676±98 382 µm3 and 16 576±2646 µm2, respectively; P<0.05). Phospho-VEGFR2 expression was much weaker in the sections of CNV lesions in RSV injected mice compared with that in control (P<0.05). Intravitreal injection of RSV exerts an inhibitory effect on CNV, which may through suppressing endothelial cell migration, tube formation and VEGFR2 phosphorylation.