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

doi:10.13560/j.cnki.biotech.bull.1985.2016.02.029

Abstract

Abstract: 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/mL 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 mRNA 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 lepR, 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 mRNA expression of related genes.The expression levels of gene lepR, 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.

Key words: subcutaneous preadipocyte, leptin, AMPK, signal pathway

HUANG Ying, YANG Ming-hua, KONG Ling-fu, HAO Mei-lin, GAO Shi-zheng, LI Yong-neng, ZHAO Su-mei. The Regulation of Leptin-mediated AMPK Signal Pathway on Lipid Metabolism in Porcine Subcutaneous Preadipocyte[J]. Biotechnology Bulletin, 2016, 32(2): 211-218.

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