Protective effect of puerarin on diabetic retinopathy in rats.

Puerarin is a major active ingredient extracted from the traditional Chinese medicine Ge-gen. The purpose of this study is to investigate the protective effect of puerarin on diabetic retinopathy (DR) and its mechanisms in rats. Seventy-two male Wistar rats were selected and divided at random into three main groups: control group, streptozotocin (STZ) group and puerarin + STZ group. Retinal histopathological observation and electron microscopic examination were performed; retinal vascular endothelial growth factor (VEGF) and hypoxia inducible factor 1 (HIF-1alpha) gene expressions were examined by Reverse transcription-polymerase chain reaction (RT-PCR) analysis. Results showed that the DR induced by STZ was significantly reduced by the treatment of puerarin as judged by the reduction of morphological changes of inner nuclear layer and outer nuclear layer at any time-point. Puerarin regulates expressions of VEGF and HIF-1alpha stimulated by STZ. It was concluded that puerarin exerts significant protective effects against DR in rats, likely regulating angiogenesis factors expressions, and thus may be an effective and promising medicine for treatment of DR.