Lipid Droplet Formation in the Pre-adipocytes of Leptin-overexpressed Pig

doi:10.13560/j.cnki.biotech.bull.1985.2020-0072

Abstract

Abstract: This work aims to investigate the effect of endogenous leptin overexpression on lipid droplet formation in pig adipocytes and to provide a theoretical basis for studying the molecular mechanism of Leptin regulating lipid metabolism. The subcutaneous adipocytes of leptin-overexpressed and wild-type pig were isolated and cultured under aseptic condition. Then these cells were induced to be differentiated to produce lipid droplets（LDs）. The area of a lipid droplet and the content of the lipid were observed by microscope after Oil Red O and Bodipy staining. Then the expression levels of lipid droplet formation-related genes were determined by Q-PCR. The cells differentiated to form LDs after 4 d of induction. The results from the Oil Red O and Bodipy staining showed that the number of lipid droplets and lipid contents in the leptin-overexpressed porcine adipocytes were significantly lower than those in the wild type（P<0.05）. Furthermore,the expression levels of lipogenesis-related genes PPAR γ,SCAP,SREPB1 and PLIN2 in the leptin-overexpressed porcine adipocytes were significantly lower compared to the wild type（P<0.01）. Leptin overexpression inhibited the formation of LDs by down-regulating PPARγ,SREPB1,SCAP and PLIN2 genes expression in porcine pre-adipocytes.

Key words: leptin, porcine adipocytes, lipid droplets, lipogenesis and metabolism-related genes

HU Bin-yue, HU Yang, CHENG Wen-min, ZHAO Su-mei, ZHAO Hong-Ye, WEI Hong-Jiang. Lipid Droplet Formation in the Pre-adipocytes of Leptin-overexpressed Pig[J]. Biotechnology Bulletin, 2020, 36(8): 111-119.

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