Leptin介导AMPK信号通路对猪皮下前脂肪细胞脂类代谢调控的研究

The Regulation of Leptin-mediated AMPK Signal Pathway on Lipid Metabolism in Porcine Subcutaneous Preadipocyte

以体外培养的猪原代皮下脂肪细胞为研究材料,检测Leptin介导AMPK信号通路中基因表达水平,旨在阐明Leptin介导AMPK信号通路对脂肪代谢调控的分子机制。用0和100 ng/m L Leptin分别处理脂肪细胞48 h,油红O染色鉴定脂肪细胞,试剂盒测定细胞中甘油三酯和游离脂肪酸含量,Real-time PCR方法检测皮下前脂肪细胞中AMPK信号通路中基因表达水平。研究结果表明,皮下前脂肪细胞中,Leptin组甘油三酯含量均显著低于对照组(P<0.05),表明Leptin可以降低细胞中甘油三酯和游离脂肪酸含量。Leptin组中AMPK信号通路中的基因lep R、AMPK、CPT-1基因的表达量均显著高于对照组(P<0.05),ACC基因表达量显著低于对照组(P<0.05),表明Leptin通过调控AMPK信号通路中基因表达,启动AMPK信号通路的信号传递。皮下前脂肪细胞中,lep R、AMPK和CPT-1基因表达量均与甘油三酯和游离脂肪酸含量呈显著负相关(P<0.05);ACC基因表达量与甘油三酯和游离脂肪酸含量呈显著正相关(P<0.05)。结果表明,Leptin通过激活AMPK信号通路,降低ACC基因的表达量,提高CPT-1基因表达水平,促进甘油三酯分解及脂肪酸的氧化,降低细胞中甘油三酯和游离脂肪酸的含量。

Using in vitro cultured porcine subcutaneous preadipocytes as the study material, the expression levels of related genes were measured for investigating the molecular regulation mechanism of leptin-mediated AMPK signal pathway on lipid metabolism. The subcutaneous adipocytes were treated with 0 and 100 ng/m L leptin for 48 h, and the adipocytes were identified by oil red O dyeing, and the contents of triglyceride and free fatty acids in the cells were measured by kit, and the m RNA expression levels of related genes in the AMPK signal pathway of subcutaneous preadipocytes were detected using Real-time PCR technology. The results showed that in leptin group, the content of the triglyceride of the subcutaneous preadipocytes was significantly lower（P〈0.05）compared with the control group, indicating that the leptin reduced the contents of triglyceride and free fatty acids in the cells. The expression levels of gene lep R, AMPK, CPT-1 in AMPK signal pathway were significantly higher in leptin group than control group（P〈0.05）, while the expression level of gene ACC in leptin group was significantly lower than control group（P〈0.05）, implying that leptin initiated the signal transmission in the AMPK signal pathway by regulating the m RNA expression of related genes. The expression levels of gene lep R, AMPK, and CPT-1 were significantly negatively correlated with the content of triglyceride and free fatty acid（P〈0.05）;however, the expression level of gene ACC was significantly positively correlated with the content of triglyceride and free fatty acid（P〈0.05）. In conclusion, the results suggested that leptin activated AMPK signal pathway, reduced the expression of ACC, and increased the expression of CPT-1, which therefore promoted the decomposition of triglyceride and oxidation of fatty acid, and finally decreased the contents of the triglycerides and free fatty acid in the cells.