二十碳五烯酸对白色脂肪细胞线粒体功能和氧化还原状态的影响

EFFECTS OF EICOSAPENTAENIOC ACID ON MITOCHONDRIAL FUNCTION AND REDOX STATUS IN SUBCUTANEOUS ADIPOCYTES

目的探讨二十碳五烯酸(eicosapentaenoic acid,EPA)对白色脂肪细胞(white adipocyte,WAC)线粒体功能和氧化还原状态的影响。方法从C57BL/6J小鼠腹股沟脂肪组织中分离出原代前脂肪细胞,诱导其分化成熟。同时给予不同剂量EPA全程干预,观察细胞脂滴及解耦联蛋白1(uncouplingprotein1,UCP1)表达改变;选用最适剂量,进一步观察线粒体形态与数目及其功能,细胞内氧化还原状态等。结果EPA干预后WAC细胞内脂滴变小,UCP1表达增加,50μmol/L为最适剂量;线粒体拷贝数增多,氧化呼吸功能增强(P<0.01);脂质分解(HSL、ATGL)和脂肪酸氧化(CPT1、Acox1)的关键酶mRNA表达水平增高,线粒体脂肪酸β氧化增多(P<0.05);同时线粒体产生活性氧(reactiveoxygenspecies,ROS)增加,抗氧化调控基因(SIRT1、Nrf2、HO-1)mRNA表达增加,抗氧化酶(SOD、GPx)活性增强,细胞内总ROS水平降低(P<0.05)。结论EPA可提高WAC线粒体氧化能力,减少脂质积聚,同时维持氧化还原平衡,避免氧化应激。

Objective To investigate the effects of eicosapentaenoic acid(EPA)on mitochondrial function and redox status of white adipocytes(WAC).Methods The primary adipocytes were isolated from the inguinal adipose tissue of C57 BL/6 J mice and induced to differentiate into mature adipocytes.Meanwhile,different doses of EPA were given to observe the changes of cell lipid droplets and the expression of uncoupling protein 1(UCP1).The optimal concentration was selected to further observe the mitochondrial morphology,number and function as well as the intracellular redox status.Results EPA intervention reduced lipid droplets in WAC,increased UCP1 expression,and 50 mol/L was the optimal concentration.It increased mitochondrial DNA copy number and enhanced oxidative respiratory function(P<0.01).Meanwhile,mRNA expression levels of key enzymes in lipidolysis(HSL,ATGL)and fatty acid oxidation(CPT1,Acox1)were increased,and oxidative oxygen consumption of mitochondrial fatty acid oxidation was increased(P<0.05).At the same time,the ROS production of mitochondria increased,the mRNA expression of antioxidant regulatory genes(SIRT1,Nrf2,HO-1)increased,the activity of antioxidant enzymes(SOD,GPx)increased,and the total intracellular ROS level decreased(P<0.05).Conclusion EPA improved oxidative capacity of WAC,reduced lipid accumulation,maintained redox balance and prevented oxidative stress.