摘要
目的:探讨慢性酒精摄入对肝组织病理学改变的影响及上皮-间充质转化对肝纤维化形成的作用。方法:将30只雄性C57BL/6小鼠随机分为3组:对照组灌胃给予与酒精组等体积的蒸馏水,低剂量和高剂量酒精组分别灌胃给予2.0 g·kg-1·d-1和4.0 g·kg-1·d-1酒精5个月。肝组织病理学改变和纤维化分别用HE和Masson三染色观察;荧光标记的TUNEL法检测肝组织细胞凋亡;自动生化分析仪检测血清丙氨酸氨基转移酶(ALT)和天冬氨酸氨基转移酶(AST)的活性;肝组织成纤维细胞特异性蛋白1(FSP-1)、α-平滑肌肌动蛋白(α-SMA)和E-钙黏素表达采用免疫荧光观察;E-钙黏素、α-SMA、FSP-1、转化生长因子β1(TGF-β1)和缺氧诱导因子1α(HIF-1α)蛋白表达水平用Western blotting检测。结果:与对照组相比,小鼠酒精灌胃5个月后,血清ALT和AST活性升高;肝组织细胞凋亡增加;低剂量酒精组呈现肝脂肪变性和轻度的肝纤维化,高剂量酒精组呈现出严重的肝纤维化;肝组织丙二醛(MDA)含量升高,超氧化物歧化酶(SOD)和过氧化氢酶(CAT)下降;肝细胞E-钙黏素表达下降,α-SMA表达增加;低剂量酒精组肝细胞内白蛋白和FSP-1共定位,而高剂量酒精组肝细胞内只表达FSP-1;Western blotting检测结果显示,E-钙黏素表达下降,而α-SMA、FSP-1、TGF-β1和HIF-1α蛋白表达水平升高,但是HIF-1α蛋白表达水平在高、低酒精组之间无差别。结论:慢性酒精摄入可诱导肝纤维化,部分成纤维细胞来源于肝细胞上皮-间充质转化,其机制可能与肝细胞氧化状态、TGF-β1及HIF-1α升高有关。
AIM ： To evaluate the effect of chronic alcohol intake on the histopathological changes of the liver and to determine the contribution of epithelial-mesenchymal transition （EMT） to hepatic fibrogenesis. METItODS： Thirty male C57BL/6 mice were randomly divided into 3 groups as following： the mice in control group was given （ig） water; the mice in low-dose alcohol group （2.0 g ~ kg-~ ~ d-1） and high-dose alcohol group （4.0 g ~ kg-1 ~ d-1） were given （ig） alcohol for 5 months. Alcohol-induced histopathological changes of the liver or development of hepatic fibrosis were evalua- ted using the histological methods with HE and Masson trichrome staining. The apoptosis of the liver was detected by TUNEL fluorometric staining （counterstained with DAPI）. The activity of serum alanine aminotransferase （ALT） and as- partate aminotransferase （AST） was measured by an automated biochemical analyzer. The expression of fibroblast-specific protein 1 （FSP-1）, a-smooth muscle actin （ot-SMA） and E-cadherin in the hepatic tissues was detected by immunofluo- rescence examination. The protein levels of E-cadherin, ot-SMA, FSP-1, transforming growth factor 131 （TGF＇I31） and hy-poxia-inducible factor let （HIF-let） were analyzed by Western blotting. RESULTS： Compared with control, the activity of serum ALT and AST, and apoptotic index of liver tissues were increased in the mice treated with alcohol for 5 months. The histopathological changes of the livers in the mice of low-dose alcohol group included steatosis and mild liver fibrosis, while severe liver fibrosis was observed in the high-dose alcohol-treated mice. Chronic alcohol consumption induced the increase in malondialdehyde （MDA） level, and the decreases in the activity of superoxide dismutase （SOD） and catalase （CAT） in the livers. It also reduced E-cadherin expression and increased et-SMA expression. FSP-1 immunostaining and albumn immunostaining positive cells were co-localized in the hepatocytes of low-dose alcohol group, but only FSP-1 positive hepa- tocytes were observed in high-dose alcohol group. Chronic alcohol consumption decreased E-cadherin expression and in- creased et-SMA, FSP-1, TGF-~I and HIF-let expression in a dose-dependent manner, but the HIF-let expression was not altered between the 2 alcohol-treated groups. CONCLUSION： Chronic alcohol intake induces the progression of hepatic fibrosis. Some fibroblasts derive from hepatocytes in liver fibrosis via EMT. The underlying mechanism is associated with the changes of the redox state, and increased TGF-~I generation and HIF-I~ expression.
出处
《中国病理生理杂志》
CAS
CSCD
北大核心
2014年第1期77-84,共8页
Chinese Journal of Pathophysiology
基金
国家重大环保公益项目专项(No.200809115)
省部共建河南大学科研项目(No.SBGJ090702)
