Immunization with Leptin Promotes Fat Accumulation and Up-regulates mRNA Expression of PPARγand SREBP-1

doi:10.3969/j.issn.1674-5817.2019.04.006

Abstract

Abstract: Objectives To assess the effects of intramuscular injection of exogenous leptin on fat deposition and mRNA expression of fat metabolism related genes in subcutaneous, hypothalamus and liver of rat. Methods Thirty female SD rats were injected thrice with leptin intramuscularly. At the end point of this study, the rats were sacrificed, then the body weight, abdomen fat weight and liver weight were measured. The serum were collected and the total cholesterol, high density lipoprotein, low density lipoprotein and triglycerides were detected. Subcutaneous and abdominal fat were blocked,made into paraffin slices and stained with HE. Livers were blocked, made into frozen slices and stained with Oil Red O. Pathological analysis of fat distribution in the subcutaneous, abdominal and liver. The mRNA expression levels of abdominal fat Leptin, hypothalamus peroxisome proliferator-activatedreceptor-gamma (PPARγ) and liver sterol regulatory element binding protein-1(SREBP-1) were qualified by fluorescence quantitative PCR. Results SD rats administered with leptin immunogen displayed significantly increased body weight, total cholesterol, low density lipoprotein, triglycerides and fat deposition in subcutaneous, abdominal and liver. Conclusions Intramuscular injection of exogenous leptin promotes fat accumulation in subcutaneous, abdominal and liver of rat by up-regulating of Leptin, PPARγ and SREBP-1.

Key words: Leptin, Fat metabolism, Hyperlipidemia, Non-alcoholic fatty liver, Peroxisome proliferator- activatedreceptor-gamma (PPARγ), Sterol regulatory element binding protein-1 (SREBP-1)

CLC Number:

Q95-33

WU Li-hong, LI Hong-tao, Guan Hong-bing, GU Wei-wang, Huang Li-wen. Immunization with Leptin Promotes Fat Accumulation and Up-regulates mRNA Expression of PPARγand SREBP-1[J]. Laboratory Animal and Comparative Medicine, 2019, 39(4): 287-293.

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