缺氧在大鼠肝纤维化形成中的作用机制  

The role of hypoxia in formation of hepatic fibrosis in rats

作　　者：邓毅恒[1] 窦科峰[1] 张色华 张福琴[1] 李俊杰[1] 

机构地区：[1]第四军医大学西京医院肝胆外科,陕西西安710032 [2]南海区桂城医院药剂科,广东佛山528200

出　　处：《西安交通大学学报（医学版）》2011年第2期215-219,共5页Journal of Xi’an Jiaotong University（Medical Sciences）

摘　　要：目的探讨缺氧在大鼠肝纤维化形成中的作用机制。方法建立胆管结扎(bile duct ligation,BDL)大鼠肝纤维化模型,术后1、3、7、14、21、28 d取材,观察肝脏组织学及超微结构的改变;逆转录PCR检测转化生长因子-β1(transforming growth factor-β1,TGF-β1)、Ⅰ型胶原(collagenⅠ,Coll-Ⅰ)mRNA的表达;蛋白免疫印迹检测缺氧诱导因子-1α(hypoxia-inducible factor-1 alpha,HIF-1α)、α-平滑肌肌动蛋白(α-smooth muscle actin,α-SMA)的表达;缺氧培养原代肝星状细胞(hepatic stellate cell,HSC),逆转录PCR检测HIF-1α、TGF-β1、Coll-I mRNA的表达,蛋白免疫印迹检测α-SMA的表达。缺氧/常氧下,加TGF-β1中和抗体、HIF-1α诱导剂氯化钴(cobalt chloride,CoCl2)或抑制剂2-甲氧雌二醇(2-methoxyestradiol,2 ME2),逆转录PCR检测Coll-I mRNA表达的变化。结果①电镜下显示大鼠肝脏术后出现缺氧的表现;②术后3 d时,HIF-1α的蛋白表达升高,7 d时,TGF-β1、Coll-I mRNA及α-SMA蛋白的表达升高;③缺氧诱导HSC表达HIF-1α、TGF-β1、Coll-I mRNA及α-SMA蛋白表达的升高;④常氧下CoCl2诱导Coll-I mRNA的表达,中和抗体及2 ME2抑制缺氧诱导Coll-I mRNA的表达。结论缺氧激活HSC,增加细胞外基质的沉积,促进大鼠肝纤维化的形成,其机制与TGF-β1和HIF-α的介导信号通路密切相关。Objective To study the role of hypoxia in formation of hepatic fibrosis in rats.Methods Hepatic fibrosis models in rats were established by bile duct ligation（BDL）,and the rats were sacrificed at postoperative day 1,3,7,14,21 and 28,respectively.Then the histopathological and ultrastructural changes were observed.Expressions of transforming growth factor-β1（TGF-β1） and collagen I（Coll-I） mRNA in the whole liver were assayed by RT-PCR;the HIF-1α and α-SMA protein expressions were assayed by Western blot.Upon hypoxia,the expressions of HIF-1α,TGF-β1 and Coll-I mRNA in rat hepatic stellate cells（HSCs） were assayed by RT-PCR,and the α-SMA protein expression was assayed by Western blot.Upon hypoxia or normoxia,the expression of Coll-I mRNA was assayed by RT-PCR after cell culture was supplemented with neutralizing anti-TGF-β1 antibody,cobalt chloride（CoCl2） or 2-methoxyestradiol（2ME2）.Results ① Electron microscopy showed that hypoxia and energy metabolism dysfunction appeared in the rat livers in the early stage after surgery.② HIF-1α protein expression was increased 3 days after surgery;TGF-β1,Coll-I mRNA and α-SMA protein expressions were increased 7 days after surgery.③ Hypoxia induced the elevation of HIF-1α,TGF-β1,Coll-I mRNA and α-SMA protein expressions in HSCs.④ In normoxia,CoCl2 could induce the expression of Coll-I mRNA;in contrast,neutralizing anti-TGF-β1 antibody and 2ME2 inhibited the expression of Coll-I mRNA upon hypoxia.Conclusion Hypoxia activates HSC and increases the production of Coll-I via TGF-β1-dependent and HIF-1α-dependent signaling pathway.Therefore,hypoxia may play an important role in the development of hepatic fibrosis.

关 键 词：肝纤维化 缺氧 缺氧诱导因子-1Α 转化生长因子-Β1 肝星状细胞 

分 类 号：R575.2[医药卫生—消化系统]