非酒精性脂肪肝病与肝细胞癌关系的研究

Relationship between non-alcoholic fatty liver disease and hepatocellular carcinoma

目的 :研究非酒精性脂肪肝病(non-alcoholic fatty liver disease,NAFLD)与肝细胞癌(hepatocellular carcinoma,HCC)的关系,并探讨核因子κB(nuclear factor-κB,NF-κB)以及白细胞介素6(interleukin-6,IL-6)在致病机制中的作用。方法:将小鼠分为空白对照组、常规饮食组及高脂饮食组,从第16周起至36周对高脂饮食组及常规饮食组小鼠予以二乙基亚硝胺(diethylnitrosamine,DEN)45 mg/kg每周1次腹腔注射,诱导小鼠形成HCC,空白对照组不予任何药物干预;于第15、20、25和30周在常规饮食组及高脂饮食组中各取5只小鼠,空白对照组取3只小鼠,收集血清及肝组织;第36周处死所有小鼠,同样收集小鼠血清及肝组织,并行HE染色分析肝组织形态学的变化,比较各组小鼠癌变率的差异,动态监测各组小鼠不同时期血清谷丙转氨酶(alanine aminotransferase,ALT)、谷草转氨酶(aspartate aminotransferase,AST)、甘油三酯(triglyceride,TG)和总胆固醇(total cholesterol,TC)的表达情况;ELISA法检测血清中NF-κB和IL-6的含量。结果 :喂养15周后高脂饮食组小鼠成功建立NAFLD模型,空白对照组小鼠至第36周无自发成癌现象出现。常规饮食组小鼠诱癌成功率为40.0%(8/20),高脂饮食组小鼠诱癌成功率为83.3%(13/18)。各时期小鼠血清NF-κB和IL-6在高脂饮食组小鼠中的表达水平均明显高于常规饮食组(P值均<0.01)。结论 :NAFLD能促进DEN对肝脏的致癌作用。炎性反应因子NF-κB和IL-6作为促癌因子,其异常表达在NAFLD向HCC的进展过程中发挥着重要的作用。

Objective：To investigate the relationship between non-alcoholic fatty liver disease（NAFLD） and hepatocellular carcinoma（HCC）,and to explore the role of nuclear factor-kappa B（NF-κB） and interleukin-6（IL-6） in mechanism of hepatocarcinogenesis.Methods：Mice were divided into vacuity contrast group,normal diet group and high fat diet group.After feeding for 15 weeks,diethylnitrosamine（DEN,45mg/kg） was weekly administrated by intraperitoneal injection into mice in both normal diet and high fat diet groups to gradually establish a model of HCC.The mice in blank control group were not treated with any drugs through the whole experiment.Livers and serum were individually collected from five mice in normal diet and high fat diet groups,respectively,and three mice in the blank control group in week 1 5,20,25 and 30.All the remaining mice were executed in week 36,and serum and liver pathologic gross were collected.The pathological changes of liver tissues were observed with HE staining.The differences in hepatocarcinogenesis among three groups were also analyzed.The levels of serum triglyceride（TC）,cholesterol（TC）,alanine aminotransferase（ALT） and aspartate aminotransferase（AST） were detected.The levels of serum NF-kB and IL-6 were assayed by ELISA.Results：Animal models of NAFLD were successfully established after 15 weeks of high-fat diet feeding.In the week 36,no mice in the blank control group developed HCC.Eight of 20（40.0%）mice in normal diet group developed HCC.Thirteen of 18（83.3%） mice in high fat diet group developed HCC.The levels of serum NF-kB and IL-6 in high fat diet group were significantly higher than those in the normal diet group in each period during study（all P〈0.01）.Conclusion：The results suggest that NAFLD can promote hepatocarcinogenesis in the presence of DEN.The abnormal levels of NF-kB and IL-6 play important roles during the development of HCC.