Tribbles相关蛋白及CCAAT/增强子结合蛋白同源蛋白在非酒精性脂肪肝中的表达变化

Changes of TRB3 and CHOP expression in nonalcoholic fatty liver disease in rats

目的:对Tribbles相关蛋白3(Tribbles related protein 3,TRB3)及CCAAT/增强子结合蛋白同源蛋白(CCAAT/enhancer-binding protein homologous protein,CHOP)在高脂高糖饮食诱导的大鼠非酒精性脂肪肝(nonalcoholic fatty liver disease,NAFLD)中的表达变化进行研究并探讨他们在NAFLD中的作用.方法:将30只Wistar大鼠随机分为正常组和NAFLD模型组,每组各15只.模型组大鼠采用高脂高糖饮食诱导NAFLD,正常组大鼠则给予普通饲料喂养,造模时间总计为16 wk.血清中总胆固醇(total cholesterol,TC)、甘油三酯(triglyceride,TG)、高密度脂蛋白(highdensity lipoprotein,HDL)和低密度脂蛋白(lowdensity lipoprotein,LDL)的含量采用全自动生化分析仪进行检测;应用PCR技术对肝脏中TRB3及CHOP m RNA水平的改变进行检测;应用免疫组织化学技术对肝脏中TRB3及CHOP蛋白水平的改变进行检测;采用流式细胞仪检测细胞凋亡改变.结果:模型组大鼠血清中TC、TG和LDL含量较正常组大鼠显著升高(P<0.05),而HDL则明显低于正常组(P<0.05);与正常组相比,模型组大鼠肝脏中TRB3及CHOP m RNA水平均显著增加(P<0.05或P<0.01);免疫组织化学结果显示模型组大鼠肝脏中TRB3及CHOP蛋白表达水平较正常组大鼠显著升高(P<0.01);此外流式细胞仪对大鼠肝细胞凋亡进行检测发现,模型组大鼠肝细胞凋亡与正常组相比明显增多.结论:TRB3和CHOP在基因及蛋白水平表达上调可能与高脂高糖诱导的NAFLD的发生发展有关.

AIM： To investigate the changes of Tribbles related protein 3（TRB3） and CCAAT/enhancer-binding protein homologous protein（CHOP） expression in nonalcoholic fatty liver disease（NAFLD） in rats. METHODS： Thirty Wistar rats were randomly divided into a normal control group and an NAFLD group. The rats of the NAFLD group were given a high-fat, high-glucose diet for 16 weeks to induce NAFLD, while the normal control group was given an ordinary diet. The levels of total cholesterol（TC）, triglyceride（TG）, low-density lipoprotein（LDL） and highdensity lipoprotein（HDL） were detected with an automatic biochemical analyzer. The expression of TRB3 and CHOP m RNAs in the liver was detected by real-time quantitative PCR. The expression of TRB3 and CHOP proteins in liver tissue was detected by immunohistochemistry. Cell apoptosis was detected by fl ow cytometry. RESULTS： The levels of TC, TG, and LDL in the NAFLD group were significantly higher than those in the normal control group（P〈0.05）, while the level of HDL was lower than that in the normal control group（P〈0.05）. Compared with the normal group, levels of TRB3 and CHOP m RNAs and proteins in the NAFLD group were significantly increased（m RNA： P〈0.05 or P〈0.01; protein： P〈0.01）. Flow cytometry analysis showed that the apoptosis in the NAFLD group was higher than that in the normal control group. CONCLUSION： The changes of TRB3 and CHOP expression may play important roles in the development of NAFLD.