脂联素对犊牛肝细胞脂氧化关键酶表达的影响

Effects of adiponectin on the expression of key enzyme genes involved in fatty acid oxidation in bovine hepatocytes cultured in vitro

体外原代培养犊牛肝细胞,添加0、16、64和128μg/L脂联素(adiponectin,ADPN),分别培养4、8h后,提取细胞总RNA。应用实时荧光定量PCR方法,检测脂氧化关键酶脂酰辅酶A氧化酶(ACO)、肝脏脂肪酸结合蛋白(L-FABP)、肉碱脂酰转移酶-Ⅰ(CPTⅠ)、肉碱脂酰转移酶-Ⅱ(CPTⅡ)mRNA表达变化。结果显示,在ADPN作用4h后,ACO、L-FABP、CPTⅠ、CPTⅡ基因mRNA水平均随ADPN浓度的增加而增加,且均显著高于对照组,呈剂量依赖关系;作用8h时,ACO表达也增加,但差异不显著,L-FABP在中高剂量组显著高于对照组,CPTⅠ和CPTⅡ在各ADPN处理组均显著高于对照组。结果表明,ADPN可显著促进脂氧化关键酶的表达,增强肝脏脂氧化作用,减少肝脂储存。

The objective of this study was to investigate the effects of adiponectin（ADPN）on the transcription levels of key enzymes involved in fatty acid oxidation in bovine hepatocytes cultured in vitro.The total RNA was isolated from hepatocytes,which were treated with different concentrations of ADPN for 4 h and 8 h,respectively.The mRNA expression levels of the key lipid oxidative genes,including acyl-CoA oxidase（ACO）,liver fatty acid binding protein（L-FABP）,carnitine palmityltransferase-Ⅰ（CPTⅠ）,and carnitine palmityltransferase-Ⅱ（CPTⅡ）,were determined using fluorescent quantitative real time PCR.The results showed that the mRNA expression levels of ACO,L-FABP,CPTⅠand CPTⅡ increased in a dose-dependent manner after 4 h of ADPN-treated,and were significantly higher in ADPN-treated groups than in control group.In addition,after 8 h of ADPN-treated,the mRNA expression levels of ACO were higher in ADPN-treated groups than in control group,but there was no statistical significance.The mRNA expression levels of FABP were significantly higher in middle and high-dose groups than in control group.And CPTⅠand CPTⅡ were higher in all ADPN-treated groups than in control group.In summary,the results of this study indicate that ADPN promotes lipid oxidation of hepatocytes by up-regulating the mRNA expression levels of the key genes involved in lipid oxidation,thereby enhancing the hepatic lipid oxidation and reducing hepatic lipidosis.