非酒精性脂肪性肝纤维化动物模型的改良和建立

The study to the mouse models of hepatic non-alcoholic steatofibrosis

目的:构建一种较为简便可靠的非酒精性脂肪性肝纤维化(NASF)小鼠模型。方法:选择C57BL/6J雄性小鼠,采用蛋氨酸-胆碱缺乏饲料(MCD)联合每周1次腹腔注射10%CCl4-橄榄油溶液(剂量为2 mL/kg),造模第4周、第6周末处死动物采血和肝组织,检测各组血清肝功能(ALT、AST、TBIL)水平,血清和肝脏甘油三酯(TG)含量,观察各组肝组织HE染色、油红O染色、Masson染色情况,采用免疫组织化学方法检测肝组织α-平滑肌肌动蛋白(α-SMA)表达情况。结果:相比对照组,模型组小鼠血清ALT、AST、TBIL活性明显升高(P<0.01);肝脏TG含量显著增加(P<0.01);模型组肝组织出现广泛炎症反应、脂肪变性、胶原沉积;半定量分析显示,脂滴面积、胶原染色面积及α-SMA蛋白阳性表达面积显著增加(P<0.01);其中6周模型组较4周模型组病理改变更为明显。结论:采用MCD联合反复低剂量腹腔注射CCl4可成功建立NASF小鼠模型。

Objective:To establish a hepatic non-alcoholic steatofibrosis(NASF)mouse model by the combination of methionine-choline-deficient diet(MCD)and repeated injection of carbon tetrachloride(CCl4).Methods:C57BL/6J mice were randomly divided into the control group and the model group.The model mice were fed with MCD,and intraperitoneally injected by 10%CCl4 once a week(2 mL/kg body weight),while the control group was fed with methionine-choline-supplemented diet(MCS)only.When all mice were killed at 4th and 6th weeksrespectively,the serum and the liver were collected.The histological analysis was conducted by HE staining,Oil Red O staining and Masson staining.The hepatic alpha smooth muscle ctin(α-SMA)protein expression was detected by immunohistochemistry.In addition,serum liver function and liver triglyceride levels were measured.Results:Compared with the control group,model group mice were significantly increased(P<0.01)in the activities of ALT,AST and TBIL in serum and the Triglyceride content in the liver.The liver tissue in model group mice showed obvious inflammation,steatosis and fibrosis.Theα-SMA protein expression markedly increased,compared with the control group.Moreover,the pathological changes in the 6-week were more serious than those in the 4-week model mice.Conclusion:The NASF animal model can be established successfully by the combination of MCD and repeated injection of CCl4.