Huangqi Decoction Ameliorates Streptozotocin-Induced Rat Diabetic Nephropathy through Antioxidant and Regulation of the TGF-β/MAPK/PPAR-γ Signaling.

Background/Aims: Huangqi Decoction (HQD) has been traditionally used to treat diabetes mellitus in China. The present study was carried out to assess the protective effect of HQD on diabetic nephropathy (DN) using the streptozotocin-induced (STZ) diabetic rats. Methods: Diabetes was induced by a single intraperitoneal injection of STZ (60 mg/kg) in male Wistar rats. 40 diabetic rats were divided into 5 groups: vehicle-treated (DN group), 0.45, 0.15, 0.05 g/kg HQD-treated diabetic group (HQD group) and 1 mg/kg rosiglitazone-treated diabetic group (RGZ group). 16 normal rats were randomly divided into 2 groups: vehicle-treated normal control group (NC) and 0.45 g/kg HQD-treated normal control group (NC+0.45 g/kg HQD). At the end of 8-week experiment, we measured changes of renal pathological morphology, function, antioxidant enzyme levels and the activation of TGF-β/PPAR-γ/MAPK signaling pathway. Results: After hQd treatment, renal function, including blood urea nitrogen (BUN), 24-h albuminuria and blood glucose level were improved significantly; meanwhile, impaired kidney redox balance was diminished in diabetic rats. The activation of TGF-β, phospho-JNK, phospho-p44/42, p47 and p42 phox was blocked and the decrease in PPAR-y in diabetic rats was attenuated by treatment with HQD in a dose-dependent manner. Conclusion: These results suggest that HQD shows therapeutic efficacy in DN characterized by renal dysfunction and pathological changes through hypoglycemic and antioxidant effects. [ABSTRACT FROM AUTHOR]