miR-130a在猪皮下脂肪细胞分化中的调节作用

Effects of miR-130a on Porcine Adipocyte Differentiation

为研究miR-130a对猪皮下脂肪细胞分化的影响及可能机制,本试验分离猪皮下脂肪前体细胞,诱导分化为成熟脂肪细胞,检测脂肪细胞分化过程中脂滴变化及miR-130a及其可能靶基因TNF-α和PPARγ的表达模式.同时合成miR-130a mimics及inhibitor对细胞进行转染,并以乱序序列作为阴性对照(NC).细胞转染24 h后进行诱导分化,连续诱导8 d,检测各处理细胞的聚脂情况及甘油三酯含量变化,荧光定量PCR检测脂肪细胞分化相关基因的表达变化.结果显示,猪皮下脂肪前体细胞分化过程中脂滴逐渐变大增多,miR-130a、TNF-α和PPARγ的表达模式具有一定的相似性.转染结果显示,相对于对照组,miR-130a mimics转染组细胞脂滴减少变小,甘油三酯含量降低(P<0.05),脂肪细胞分化相关基因LPL、PPARγ、adiponectin、FASN和葡萄糖转运相关基因GLUT1,GLUT4以及JNK通路上的PDE3B的表达均比对照组显著下调(P<0.01);而miR-130a inhibitor转染组细胞则脂滴增多,甘油三酯含量提高(P<0.05),但大部分分化相关基因的表达与对照组无显著差异,提示miR-130a可能不只通过单一的靶基因影响脂肪细胞分化.其结果为后续深入研究miR-130a调节猪脂肪细胞分化的通路及机制奠定基础.

To investigate the regulatory effects and mechanism of miR-130a in the differentiation of porcine adipocyte, porcine pre-adipocyte were separated and treated with insulin, dexamethasone, oleic acid and octanoic acid for eight days. The accumulation of lipid droplets and the expression profile of miR-130a and its potential target TNF-α and PPARγ were examined. The mimics or inhibitor of miR-130a were transfected at 24 hours prior to the eight-day induction. The lipid droplets and the amount of triglycerides （TG） were detected by oil red 0 and TG assays. The expressions of fatty synthesis associated genes were quantified by real-time peR. The result showed similarity expression profiles of miR-130a, TNF-α and PPARγ. during adipocyte differentiation as the lipid droplets growing larger. Overexpression of miR-130a attenuated the accumulation of lipid droplets with the decrease of the triglycerides （P 〈 0. 05 ） and the expression of fatty differentiation associated genes LPL （lipoprotein lipase）, PPARγ （proliferator-activated receptor-γ ） , adiponectin, FASN （fatty acid synthase）, PDE3B （ phospho- diesterase 3B）, GLUT （ glucose transporter） 1, and GLUT4 （ P 〈 0.01 ）. Inhibitor of miR-130a suppressed lipid droplets accumulation and increased the triglyceride levels（P 〈 0.05 ）, however, most tested genes had no significantly change over the control group, suggesting that miR-130a was not the only effector for adipocyte differentiation.