A high-fat diet increases body fat mass and up-regulates expression of genes related to adipogenesis and inflammation in a genetically lean pig

• Published in: Journal of Zhejiang University. B. Science Vol. 19; no. 11; pp. 884 - 894
• Main Authors: Yang, Xue-fen, Qiu, Yue-qin, Wang, Li, Gao, Kai-guo, Jiang, Zong-yong
• Format: Journal Article
• Language: English
• Published: Hangzhou Zhejiang University Press 01.11.2018; Springer Nature B.V
• Subjects: Adipocytes - cytology; Adipogenesis; Adipogenesis - genetics; Adipose tissue; Adipose Tissue - metabolism; Adiposity; Animals; Biomedical and Life Sciences; Biomedicine; Body fat; Body Weight; Carnitine; Cholesterol; Cholesterol - blood; Cholesterol, HDL - blood; Cholesterol, LDL - blood; Density; Diacylglycerol O-acyltransferase; Diet; Diet, High-Fat; Diglycerides; Energy intake; Fatty acid-binding protein; Fatty acids; Fatty-acid synthase; Gene expression; Genes; High cholesterol diet; High density lipoprotein; High fat diet; Hogs; Immune response; Immune system; Inflammation - genetics; Insulin; Insulin - blood; Leptin; Leptin - blood; Lipid Metabolism; Lipids; Liver; Male; Metabolism; Obesity; Obesity - genetics; Oxidation; Peroxisome proliferator-activated receptors; Proteins; Random Allocation; Sterol regulatory element-binding protein; Swine; Tissues; Triglycerides - blood; 瘦肉型猪; 高脂膳食; Diet-induced obesity; High-fat diet; Genetically lean pig; Adiposity deposition; Inflammation; 脂肪沉积; S816; 膳食引起的肥胖; Microarray analysis; 基因芯片分析炎症; Genetically lean pig; Diet-induced obesity; High-fat diet; Adiposity deposition; Microarray analysis; Inflammation
• ISSN: 1673-1581; 1862-1783
• DOI: 10.1631/jzus.B1700507

Because of their physiological similarity to humans, pigs provide an excellent model for the study of obesity. This study evaluated diet-induced adiposity in genetically lean pigs and found that body weight and energy intake did not differ between controls and pigs fed the high-fat (HF) diet for three months. However, fat mass percentage, adipocyte size, concentrations of total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C), insulin, and leptin in plasma were significantly higher in HF pigs than in controls. The HF diet increased the expression in backfat tissue of genes responsible for cholesterol synthesis such as Insig-1 and Insig-2 . Lipid metabolism-related genes including sterol regulatory element binding protein 1c ( SREBP-1c ), fatty acid synthase 1 (FASN1), diacylglycerol O-acyltransferase 2 (DGAT2), and fatty acid binding protein 4 (FABP4) were significantly up-regulated in backfat tissue, while the expression of proliferator-activated receptor-α (PPAR-α) and carnitine palmitoyl transferase 2 (CPT2), both involved in fatty acid oxidation, was reduced. In liver tissue, HF feeding significantly elevated the expression of SREBP-1c , FASN1 , DGAT2 , and hepatocyte nuclear factor-4α ( HNF-4α ) mRNAs. Microarray analysis further showed that the HF diet had a significant effect on the expression of 576 genes. Among these, 108 genes were related to 21 pathways, with 20 genes involved in adiposity deposition and 26 related to immune response. Our results suggest that an HF diet can induce genetically lean pigs into obesity with body fat mass expansion and adipose-related inflammation.