脂肪肝小鼠的肝脏脂质代谢相关基因表达特征分析

Characterization of lipid metabolism-related genes in mouse fatty liver

目的分析ob/ob肥胖小鼠脂肪肝中脂质代谢相关基因的表达特征。方法 18周龄雄性ob/ob及其同窝对照小鼠各4只,禁食16h后处死。检测小鼠体质量、肝脏湿质量/体质量、肝脏三酰甘油(TG)水平;用H-E和油红O染色观察肝脏的形态结构和脂质沉积情况;用实时荧光定量PCR方法检测肝脏脂质代谢相关基因的mRNA表达情况。结果 Ob/ob小鼠体质量、肝脏湿质量/体质量和肝脏组织TG水平均高于对照小鼠(P<0.05),H-E和油红O染色显示ob/ob小鼠发生肝脏脂质沉积;肝脏脂肪酸转位酶(CD36)、脂肪酸结合蛋白1(FABP1)、脂肪酸合酶(FASN)、乙酰辅酶A羧化酶1(ACC1)、极长链脂肪酸延长酶6(ELOVL6)和硬脂酰辅酶A去饱和酶1(SCD1)等mRNA表达水平在ob/ob小鼠肝脏均高于对照小鼠(P<0.05),而过氧化物酶体增殖剂激活受体α(PPARα)、软脂酸辅酶A氧化酶1(ACOX1)、载脂蛋白B(ApoB)和微粒体TG转移蛋白(MTP)mRNA在两组小鼠肝脏中的mRNA表达水平差异无统计学意义。结论 Ob/ob小鼠肝脏的脂肪酸摄取和从头合成相关基因的mRNA表达水平升高,而脂肪酸氧化及脂质向肝外转运的相关基因的mRNA表达水平无明显改变。

Objective To characterize the expression of lipid metabolism-related genes in the fatty liver of obese ob/ob mice.Methods Four 18-weeks old male ob/ob and 4 control mice were sacrificed after 16 h fasting.Their body mass,ratio of liver wet mass to body mass and liver triglyceride contents were examined.H-E staining and Oil red O staining were performed to observe the histological changes and lipid deposition of the liver.Real-time quantitative RT-PCR was used to detect mRNA expression of lipid metabolism-related genes in the liver.Results The body mass,ratio of liver wet mass to body mass and liver triglyceride contents were significantly higher in ob/ob mice than those in control mice（P〈0.05）.H-E staining and Oil red O staining showed severe hepatic steatosis in the ob/ob mice.The mRNA levels of fatty acid translocase（CD36）,fatty acid binding protein 1（FABP1）,fatty acid synthase（FASN）,acetyl-CoA carboxylase 1（ACC 1）,elongation of very long chain fatty acids family member 6（ELOVL6） and stearoyl-CoA desaturase 1（SCD1） were significantly higher in ob/ob mice than those in control mice（P〈0.05）;and there were no significant differences in the mRNA levels of peroxisome proliferator-activated receptor α（PPARα）, palmitoyl-CoA oxidase（ACOX1）, apoprotein B（ApoB） or microsomal triglyceride transfer protein（MTP） between the two groups（P〈0.05）.Conclusion The genes closely related to fatty acid uptake and de novo fatty acid synthesis are up-regulated in ob/ob liver,and those related to fatty acid oxidation and lipid transportation and VLDL secretion are not greatly affected at mRNA level.