[The effects of VEGF-R inhibitor on podocytopathy of rats with type I diabetic nephropathy]

Abstract

Aim: To explore the effect of VEGF inhibitor SU5416 on podocytopathy of rats with type I diabetic nephropathy.

Methods: Thirty male SD rats were randomly divided into three groups: normal control group(NC), diabetic nephropathy group(DN) and diabetic nephropathy treated with SU5416 group(SU5416). Rats with DN were induced by STZ. At the end of 8 weeks after SU5416 treatment, body weight (BW), kidney weight (KW), 24 h urine albuminuria excretion rate(24 h UAER), plasma glucose and creatinine were detected respectively. Renal morphology were stained with periodic acid-Schiff (PAS). And the expression of podocyte-specific genes nephrin and podocin were detected by immunofluorescence. The mRNA levels of genes and VEGF were assessed by real time-PCR respectively.

Results: Compared with NC group, DN rats'BW were decreased but the KW were increased, and the levels of blood glucose, creatinine, 24 h UAER and kidney cortex VEGF mRNA were significantly higher. The expression of nephrin and podocin were decreased(P<0.05), and GBM thickening and mesangial matrix expansion were developed. Treatment with SU5416 leads to a marked decrease of KW and the level of 24 h UAER. Concurrently, the expressions of nephrin and podocin were revert partly in response to SU5416(P<0.05), and pathological changes were successfully ameliorated. However, the KW, glucose, creatinine and the level of VEGF mRNA were not significantly affected by SU5416 treatment(P>0.05).

Conclusion: VEGF-R inhibitor SU5416 can obviously ameliorate albuminuria and histologic changes, and restore the expression of podocyte-specific genes nephrin and podocin in DN rats, suggesting that VEGF-R inhibitor is beneficial for the repair of podocytes in DN, which might be an important adjunct for podocytopathy therapy.