缬沙坦对肝纤维化大鼠脂联素及脂联素受体2表达的影响

Effects of valsartan on expression of adiponectin and adiponectin receptor 2 in rats with hepatic fibrosis

目的探讨血管紧张素Ⅱ1型受体拮抗剂缬沙坦对肝纤维化大鼠脂联素(ADN)及ADN受体2(AND-R2)表达的影响。方法选36只雄性Wistar大鼠分为对照组、模型组、药物组,用四氯化碳(CCl4)背部皮下注射法制备大鼠肝纤维化模型,药物组于造模开始每只大鼠缬沙坦灌胃(30 mg·kg-1·d-1),8周末处死。肝组织苏木素-伊红(HE)染色和Masson染色,进行肝纤维化分期。酶联免疫吸附测定法(ELISA)测定血清ADN、肿瘤坏死因子(TNF)-α、转化生长因子-β1(TGF-β1)的浓度,逆转录聚合酶链式反应(RT-PCR)检测肝组织中ADNm RNA(ADN-R2)m RNA水平,蛋白印迹法检测肝脏ADN、ADN-R2、Ⅰ型胶原表达水平。结果 (1)模型组大鼠造模成功,药物组肝组织纤维化程度较模型组明显减轻;(2)模型组较对照组血清脂联素水平降低,TNF-α、TGF-β1水平增高(P<0.01),药物组较模型组ADN增高(P<0.01)、TNF-α和TGF-β1水平下降(P<0.01或<0.05);(3)肝脏ADN和ADN-R2m RNA水平模型组较对照组明显下降(P<0.01),药物组较模型组增高(P<0.05);(4)模型组较对照组ADN、ADN-R2蛋白表达减少,Ⅰ型胶原蛋白增高(P<0.01),药物组较模型组ADN蛋白表达增高(P<0.01),ADNR2蛋白表达增高(P<0.05),Ⅰ型胶原蛋白下降(P<0.05)。结论血管紧张素受体拮抗剂缬沙坦可能通过增高大鼠ADN、ADN-R2的表达,减少TNF-α、TGF-β1水平,减轻肝脏炎症,发挥抗肝纤维化作用。

Objective To investigate the effects of angiotensin Ⅱtype 1 receptor antagonist valsartan on the expression of adiponectin （ADN） and ADN receptor 2 （ADN-R2） in rats with hepatic fibrosis. Methods Thirty-six male Wistar rats were divided into the control group, model group and drug group. The rat model with liver fibrosis was prepared by subcutaneous injection of CCl4 at the back. Each rat in the drug group was given valsartan （30 mg·kg-1·d-1） by intragastric administration at the beginning of modeling, and was sacrificed at the end of eight weeks. HE staining and Masson staining in the liver tissues were performed for the staging of hepatic fibrosis. The concentra-tion of serum ADN, tumor necrosis factor-α （TNF-α） and transform growth factor-β1 （TGF-β1） were determined by ELISA. The mRNA levels of ADN and ADN-R2 in the liver tissues were determined by reverse transcription poly-merase chain reaction （RT-PCR）. The expression levels of ADN, ADN-R2 and collagen Ⅰin the liver tissues were examined by Western blot. Results ①The model group was successfully modeled, and the degree of hepatic fibrosis in the drug group significantly decreased compared with that in the model group. ②The serum level of ADN de-creased in the model group compared with that in the control group, whereas the levels of TNF-α and TGF-β1 in-creased （P〈0.01）. The serum level of ADN increased in the model group compared with that in the control group （ P〈0.01）, whereas the levels of TNF-αand TGF-β1 decreased （P〈0.01 or〈0.05）. ③The mRNA levels of ADN and ADN-R2 in the liver tissues significantly decreased in the model group compared with that in the control group, whereas the levels of TNF-α and TGF-β1 increased （P〈0.01）. ④The protein expression of ADN and ADN-R2 decreased in the model group compared with that in the control group, whereas the protein expression of collagenⅠincreased （P〈0.01）. The protein expression of ADN increased in the drug group compared with that in the model group （ P〈0.01）, whereas the protein expression of ADN-R2 increased （P〈0.01）, and the protein expression of collagenⅠincreased （P〈0.05）. Conclusion Angiotensin receptor antagonist valsartan may increase the expression of ADN and ADN-R2 in rats, de-crease the levels of TNF-αand TGF-β1, reduce the liver inflammation, and show effect of anti-hepatic fibrosis.