OBJECTIVETo study the effect and mechanism of Kangxianling (KXL, a TCM herbal compound) on renal interstitial fibrosis induced by unilateral ureteral obstruction (UUO).

METHODSEighteen male SD rats were randomly divided into 3 groups, 6 in each group, the sham operated group, the model group, and the KXL group. Renal interstitial fibrosis model was established in rats by UUO. After rats were raised for additional 14 days, their body weight, serum levels of creatinine (SCr) and blood urea nitrogen (BUN) were analyzed. Then rats were sacrificed, their renal pathology examined by HE staining and PASM staining; expressions of transforming growth factor-beta1 (TGF-beta1), hepatocyte growth factor (HGF) mRNA, and a-smooth muscle actin (alpha-SMA), TGF-beta1 receptor I (TbetaR I), TGF-beta1 receptor II (TbetaR II) and hepatocyte growth factor receptor (C-Met) protein in kidney tissue were determined by RT-PCR and Western blotting respectively.

RESULTSSCr and BUN in the model group were significantly higher than those in the sham operated group (P <0.05). Expressions of TGF-beta1 mRNA and a-SMA, TbetaR I , TbetaR II and C-Met protein in kidney tissue in the model group significantly up-regulated and mRNA expression of HGF significantly down-regulated, and obvious hyperplasia of the base member of glomeruli was seen. After intervention with KXL, BUN content significantly lowered, alpha-SMA, TbetaR I and TbetaR II protein expression decreased and HGF mRNA expression up-regulated significantly in the treated group, with slight pathological changes only shown as mild hyperplasia of the base member of glomeruli and renal tubules.

CONCLUSIONKXL could inhibit the protein expressions of a-SMA, TbetaR I , TbetaR II and increase the mRNA expression of HGF, which is a protective factor against renal fibrosis. Therefore, it is effective in alleviating the renal interstitial fibrosis and improving the renal function in UUO rats.