人参皂甙Rg1对单侧输尿管梗阻后大鼠肾间质纤维化的作用研究

目的观察人参皂甙Rg1对单侧输尿管梗阻(UUO)大鼠肾间质纤维化的影响。方法将雄性SD大鼠80只随机分为4组:UUO组、人参皂甙Rg1组(Rg1)、氯沙坦组(ARB)和假手术组(SOR)。从术后24 h开始,Rg1组予人参皂甙Rg1溶液腹腔注射50 mg/(kg.d),其余3组予以同等体积生理盐水腹腔注射;ARB组予氯沙坦溶液20 mg/(kg.d)灌胃,其余3组予以同等体积生理盐水灌胃,连续14 d。术后第3 d、7 d、14 d处死各组大鼠,行HE、Masson和PAS染色,动态观察肾间质病理学改变。采用荧光定量PCR、Western蛋白印迹、免疫组织化学方法从mRNA和蛋白质水平观察各组肾脏组织转化生长因子-β1(TGF-β1)的表达情况。结果UUO组呈进行性肾间质纤维化改变,包括小管的萎缩、扩张、炎细胞浸润、肾间质胶原的沉积。Rg1组和ARB组上述肾脏病理损害明显减轻。UUO组肾脏组织TGF-β1的表达量较SOR组升高(P<0.05),尤以7~14 d明显。Rg1组和ARB组TGF-β1的表达量与UUO组比较有明显的下降(P<0.05)。结论人参皂甙Rg1对UUO所致的大鼠肾间质纤维化的形成有明显的抑制作用,其作用机制可能与降低TGF-β1的表达有关。

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.