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

OBJECTIVE: To study the effect of Astrangalus mongholicus (AM) on the expression of Connective Tissue Growth Factor (CTGF) in SD rats with Unilateral Ureteral Obstruction (UUO) and elucidate the mechanism underlying the renorotective effects of AM.

METHODS: 36 Sprague-Dawley rats were randomly divided into 3 groups: sham-operation group (Sham), UUO group (UUO) and UUO + AM group (AM). After administration of AM (10 g/kg x d) for 7 and 14 days, the dynamic histological changes of renal interstitial tissues were observed and renal damage including tubular impairment and interstitial fibrosis were quantified on HE and Masson stained tissue sections. The expressions of CTGF and alpha-smooth muscle actin (alpha-SMA) were measured by immunohistochemistry staining sections. The mRNA of CTGF and alpha-SMA were reversely transcribed and quantified to real-time PCR. The expression of CTGF protein was assessed by Western blot.

RESULTS: Renal damage was exacerbated and the expressions of alpha-SMA and CTGF significantly increased in UUO group compared with those of Sham group (P < 0.05) at each time point. Tubular impairment and interstitial fibrosis were alleviated, and up-regulations of expressions of CTGF and alpha-SMA were significantly depressed by AM treatment (P < 0.05).

CONCLUSIONS: AM can ameliorate renal interstitial fibrosis induced by UUO in rats. The mechanism of its antifibrotic effects may be related to the down-regulation of CTGF expression, following suppression of tubulo-epithelial mesenchymal transdifferentation in renal intersitial progress.