Adipose tissue remodeling in a novel domestic porcine model of diet-induced obesity

OBJECTIVE: To establish and characterize a novel domestic porcine model of obesity. DESIGN AND METHODS: Fourteen domestic pigs were fed normal (lean, n=7) or high-fat/high-fructose diet (obese, n=7) for 16 weeks. Subcutaneous abdominal adipose tissue biopsies were obtained after 8, 12 and 16 weeks of diet, and pericardial adipose tissue after 16 weeks, for assessments of adipocyte size, fibrosis, and inflammation. Adipose tissue volume and cardiac function were studied with multi-detector computed-tomography, and oxygenation with magnetic resonance imaging. Plasma lipids profiles, insulin resistance, and markers of inflammation were evaluated. RESULTS: Compared with lean, obese pigs had elevated cholesterol and triglycerides levels, blood pressure, and insulin resistance. Both abdominal and pericardial fat volume increased after 16 weeks of obese. In abdominal subcutaneous adipose tissue, adipocyte size and both tumor necrosis factor (TNF)-α expression progressively increased. Macrophage infiltration showed in both abdominal and pericardial adipose tissues. Circulating TNF-α increased in obese only at 16 weeks. Compared with Lean, obese pigs had similar global cardiac function, but myocardial perfusion and oxygenation were significantly impaired. CONCLUSION: A high-fat/high-fructose diet induces in domestic pigs many characteristics of metabolic syndrome, which is useful to investigate the effects of the obesity.