益肾活血通络法对单侧输尿管梗阻大鼠肾脏缺氧诱导因子——血管内皮生长因子信号通路干预作用的实验研究

Regulation of HIF-VEGF signaling pathway by Yishen Huoxue herbs in a rat UUO model

目的 探讨缺氧诱导因子α(hypoxia-inducible factorα,HIF-α)诱导血管内皮生长因子(vascular endothelial growth factor,VEGF)表达的作用机制及微血管损伤发生的机制及"益肾活血通络法"干预效果,为中医药治疗肾间质纤维化提供新的依据。方法实验采用单侧输尿管梗阻(unilateral urethral obstruction,UUO)造成肾纤维化动物模型,并以益肾活血方、氯沙坦灌胃对其进行治疗性干预,分别在术后第7天、14天、21天采集肾脏标本,运用免疫组化法检测HIF-α、VEGF在肾脏中的分布、表达。结果 与假手术组比较,模型组、治疗组在各时间点HIF-α、VEGF表达均显著上调(P<0.01);在各时间点,益肾活血方组和氯沙坦组较模型组大鼠HIF-α、VEGF表达均下调(P<0.01)。随着干预时间的延长,模型组、治疗组HIF-α、VEGF表达都逐渐增强,但增强幅度明显下调;益肾活血方组较氯沙坦组大鼠HIF-α、VEGF下调明显,有统计学差异(P<0.05)。结论 益肾活血方能有效地降低HIF-α及VEGF表达,改善UUO大鼠内源性低氧状态,减轻微血管损伤,发挥抗肾纤维化的作用。

Objective To investigate the mechanism how hypoxia-inducible factor α （HIF-α）-in duced vascular endothelial growth factor （VEGF） leads to microvascular injury, and the efficacy of Yishen Huoxue herbs in treatment of renal interstitial fibrosis, so as to provide references for treatment of renal in terstitial fibrosis using traditional Chinese medicine. Methods Renal fibrosis model of rat was constructed by unilateral urethral obstruction （UUO） and was treated with oral Tongluo Huoxue herbs and losartan. Then kidney specimen was collected at 7, 14 and 21 days after surgery, and expression and distribution of HIF-α and VEGF in kidney were determined by immunohistochemistry. Results At each of the specified time points, HIF-α and VEGF expression levels significantly increased in both the model group and the treated group than in the sham group （ P 〈 O. 01 ）, but they were lower in the treated group than in the model group （P 〈 0. 01 ）. During this period, HIF-α and VEGF levels of both the model group and treated group showed a tendency of falling back to normal, and the decrease was significantly larger in the treated group than in the model group （ P 〈 0. 05 ）. Conclusion Yishen Huoxue herbs can effectively reduce HIF-α and VEGF expression in UUO rat model, thus alleviate the endogenous hypoxia status, reduce mi crovascular injury, and play an anti-renal fibrosis role.