High-fat diets containing different amounts of n3 and n6 polyunsaturated fatty acids modulate inflammatory cytokine production in mice

Dysregulation of adipokines is a hallmark of obesity. Polyunsaturated fatty acids in fish oil may exert anti-inflammatory effects on adipose tissue mitigating the dysregulation of adipokines thereby preventing obesity. This study investigated the effects of high-fat diets containing different amounts of n3 polyunsaturated fatty acids (PUFA) on adiposity and adipokine production in mice. Mice were fed a low-fat or a high-fat diet with 16 or 45 % of energy from corn oil (low n3 PUFA) in comparison with a high-fat diet containing soybean or high-oleic sunflower oil (adequate n3 PUFA) or flaxseed or fish oil (high n3 PUFA) for 11 weeks. High-fat diets, regardless of types of oils, significantly increased body fat mass and body weights compared to the low-fat diet. Adipose fatty acid composition and contents reflected dietary fatty acid profiles. The high-fat fish oil diet significantly increased adiponectin and reduced leptin concentrations in both plasma and adipose tissue; it did not elevate plasma insulin concentration compared to the high-fat corn oil diet. All high-fat diets elevated concentrations of plasminogen activator inhibitor-1 (PAI-1) and monocyte chemoattractant protein-1 (MCP-1) but lowered resistin concentrations in both plasma and adipose tissue. In conclusion, fish oil may be beneficial in improving insulin sensitivity by upregulation of adiponectin and downregulation of leptin production; n3 and n6 PUFA do not play a role at the dietary levels tested in reducing adiposity and production of pro-inflammatory cytokines (leptin, PAI-1, MCP-1 and resistin) and anti-inflammatory cytokine adiponectin.