[The effect of ginsenoside Rg1 on the renal interstitial fibrosis of UUO rat].

OBJECTIVE: To study the effect of ginsenoside Rg1 on the renal interstitial fibrosis caused by unilateral ureteral obstruction (UUO) of rats.

METHODS: 80 healthy Sprague-Dawley rats were randomly divided into 4 groups: the UUO group (UUO), sham-operation group (SOR), ginsenoside Rg1 group (Rg1) and losartan group (ARB). From the first day after initial UUO, ARB group was intragastrically administrated with losartan 20 mg/(kg x d). UUO, Rg1 and SOR groups were intragastrically administrated with identical volume of normal saline. Rg1 group was intraperitoneally injected with ginsenoside Rg1 50 mg/(kg x d). UUO, ARB and SOR groups were intraperitoneally injected with identical volume of normal saline. At day 3, 7, 14 after UUO, 6 rats selected randomly from each group were killed. The dynamic histological changes of renal interstitial tissues were observed by HE, Masson and PAS staining. The mRNA of transforming growth factor-beta1 (TGF-beta1) was quantified by real-time PCR. The protein levels of TGF-beta1 expression were assessed by Western blot and immunohistochemical method respectively.

RESULTS: In UUO kidneys, the interstitial fibrosis including tubular atrophy, loss and dilation, inflammatory cell infiltration and interstitial matrix deposition was prominent. However, these morphological changes were notably reduced in Rg1 and ARB groups, and there was no significant difference between the two groups (P > 0.05). TGF-beta1 mRNA and protein expression were increased dramatically for UUO group at postoperative day 7 and 14 (P < 0.05). TGF-beta1 expression in Rg1 and ARB groups were significantly lower than that in UUO group (P < 0.05).

CONCLUSION: Ginsenoside Rg1 can evidently inhibit UUO-induced renal interstitial fibrosis in rat, which may be related to the down regulation of TGF-beta1 expression.