Resveratrol blocks diabetes‐induced early vascular lesions and vascular endothelial growth factor induction in mouse retinas

Abstract

Vessel leakage and loss of pericytes are early signs of diabetic retinopathy (DR), which leads to vision loss. Upregulation of the vascular endothelial growth factor (VEGF) during diabetes plays a key role in mediating these vascular lesions. The aim of this study is to investigate the effects of resveratrol, a natural plant-derived phytoalexin, on vascular damage and VEGF induction in mouse retinas of early diabetes. Diabetes was induced in C57BL/6 mice by five consecutive-intraperitoneal injections of 55 mg/kg of streptozotocin (STZ). Animals injected with buffer only were used as controls. Beginning 1 month after the fifth injection of STZ or buffer, 20 mg/kg of resveratrol was administered by oral gavage daily for 4 weeks to diabetic and control mice, and all mice were killed 2 months after the injections. We assessed vessel leakage, pericyte loss and VEGF protein expression in mouse retinas of 2-month diabetes compared with controls with or without resveratrol treatment. Diabetes led to increase vessel leakage, pericyte loss and VEGF protein level in the mouse retinas compared with controls; however, these changes were effectively blocked by resveratrol treatment. Our data suggest that resveratrol is effective to decrease vascular lesions and VEGF induction in mouse retinas of early diabetes.