Thursday, June 23, 2011

Resveratrol retards progression of diabetic nephropathy

Resveratrol retards progression of diabetic nephropathy through modulations of oxidative stress, proinflammatory cytokines, and AMP-activated protein kinase

Chih-Chun Chang, Chieh-Yu Chang, Yang-Tzu Wu, Jiung-Pang Huang, Tzung-Hai Yen and Li-Man Hung

Journal of Biomedical Science 2011, 18:47 doi:10.1186/1423-0127-18-47
Published: 23 June 2011

Abstract (provisional)

Background

Diabetic nephropathy (DN) has been recognized as the leading cause of end-stage renal disease. Resveratrol (RSV), a polyphenolic compound, has been indicated to possess an insulin-like property in diabetes. In the present study, we aimed to investigate the renoprotective effects of RSV and delineate its underlying mechanism in early-stage DN.

Methods

The protective effects of RSV on DN were evaluated in streptozotocin (STZ)-induced diabetic rats.

Results

The plasma glucose, creatinine, and blood urea nitrogen were significantly elevated in STZ-induced diabetic rats. RSV treatment markedly ameliorated hyperglycemia and renal dysfunction in STZ-induced diabetic rats. The diabetes-induced superoxide anion and protein carbonyl levels were also significantly attenuated in RSV-treated diabetic kidney. The AMPK protein phosphorylation and expression levels were remarkably reduced in diabetic renal tissues. In contrast, RSV treatment significantly rescued the AMPK protein expression and phosphorylation compared to non-treated diabetic group. Additionally, hyperglycemia markedly enhanced renal production of proinflammatory cytokine IL-1beta. RSV reduced IL-1beta but increased TNF-alpha and IL-6 levels in the diabetic kidneys.

Conclusions

Our findings suggest that RSV protects against oxidative stress, exhibits concurrent proinflammation and anti-inflammation, and up-regulates AMPK expression and activation, which may contribute to its beneficial effects on the early stage of DN.