Puerarin enhances superoxide dismutase activity and inhibits RAGE and VEGF expression in retinas of STZ-induced early diabetic rats.

OBJECTIVE

To investigate the effects of puerarin on the activity of superoxide dismutase (SOD), and expressions of advanced glycation end-product (AGE) receptor (RAGE) and vascular endothelial growth factor (VEGF) in retinas of streptozotocin (STZ)-induced early diabetic rats.

METHODS

Diabetic rat models were established by inducing diabetes via intra-peritoneal injection of STZ. Rats were randomly divided into normal (control), diabetic (DM), and DM+ puerarin groups. After intra-gastric administration of puerarin (500 mg/kg/day for 4 weeks), levels of SOD and malondialdehyde (MDA) were determined in serum and retina. mRNA and protein expression levels of RAGE and VEGF in retinas were determined by real-time polymerase chain reaction (RT-PCR) (mRNA) and Western blot analysis (protein levels).

RESULTS

There was significantly lower SOD activity and significantly higher MDA in serum and retinas of the DM group compared with the two other groups (P<0.05). After treatment with puerarin, SOD activity increased and MDA content decreased in this group (P<0.05). mRNA and protein expression levels of RAGE and VEGF in the DM group were significantly higher than those of the other groups (P<0.05), and decreased after puerarin treatment (P<0.05).

CONCLUSIONS

Puerarin is able to enhance SOD activity, and inhibit RAGE and VEGF expressions in retinas of STZ-induced early diabetic rats.