[Effect of Astragalus mongholicus on expression of hepatocyte growth factor in SD rats with unilateral ureteral obstruction].

OBJECTIVE: To study the effect of Astragalus mongholicus (AM) on the expression of hepatocyte growth factor (HGF) in SD rats with unilateral ureteral obstruction (UUO) and to elucidate the mechanisms underlying the renoprotective effects of AM.

METHODS: Fifty four Sprague-Dawley rats were randomly divided into 3 groups: sham-operation group (SOR), UUO group (UUO) and UUO + AM group (AM). After administration of AM[10 g/ (kg x d)] for 3, 7 and 14 days,the histological changes of renal interstitial tissues were observed dynamically, and renal damage including tubular impairment and interstitial fibrosis were quantified on HE and Masson stained tissue sections. The protein expression of HGF and alpha-smooth muscle actin (alpha-SMA) was measured by immunohistochemistry. The mRNA expression of HGF and alpha-SMA were determined by real-time PCR. The expression of HGF and its receptor (C-met) were assessed by Western blot.

RESULTS: Renal damage was exacerbated and the expression of alpha-SMA was significantly increased in UUO group compared with those of SOR group (P < 0.05) at each time point. HGF and C-met expression peaked at the 7th day after UUO and then decreased greatly. After AM intervention, tubular impairment and interstitial fibrosis were alleviated, up-regulations of alpha-SMA expressions was significantly suppressed, whileas the expression of HGF and C-met were significantly increased when compared with UUO group (P < 0. 05) at each time point.

CONCLUSION: AM can ameliorate renal interstitial fibrosis induced by UUO in rats. The mechanisms of its antifibrotic effects may be related with the up-regulation of HGF and C-met expression, and the suppression of tubulo-epithelial mesenchymal transdifferentiation in renal intersitial progress.