Efficacy of Danggui Buxue decoction on diabetic nephropathy-induced renal fibrosis in rats and possible mechanism.

OBJECTIVE To observe the efficacy of Danggui Buxue decoction (, DBD) on diabetic nephropathy-induced renal fibrosis in rats, and to study the possible mechanism. METHODS Sixty male Goto Kakizaki (GK) rats were randomly assigned to the model group, gliquidone group, astragaloside IV group, and high-, medium- and low-doses DBD groups. After 8 weeks, changes in body weight, blood glucose, serum creatinine, serum urea nitrogen, and total cholesterol were observed. Changes in transforming growth factor-β1 (TGF-β1), Smad3, and Smad5 pathways and the expression of the fibrosis-related proteins collagen IV (col IV), α-smooth muscle actin (α-SMA), and vimentin were assessed. The degree of renal fibrosis was observed by immunohistochemistry and Mason staining. The expression of interleukin 6 (IL-6), interleukin 10 (IL-10), tumor necrosis factor (TNF-α), and C-reactive protein (CRP) in the kidneys was assessed using enzyme linked immunosorbent assay. RESULTS Our experiments showed that DBD effectively reduced blood glucose, blood urea nitrogen, and creatinine levels after 8 weeks of administration, improved renal function in diabetic rats, alleviated renal fibrosis, and reduced the renal tissue levels of IL-6, IL-10, TNF-α, and CRP. Furthermore, DBD decreased the expression of TGF-β1, Smad3, col IV, α-SMA, and vimentin in renal tissues and increased the expression of Smad5. CONCLUSIONS DBD ameliorates diabetic renal interstitial fibrosis by modulating the TGF-β1/Smads pathway.