Anti-obesity effects of DHA and EPA in high fat-induced insulin resistant mice.

Docosahexaenoic acid (DHA, 22:6) and eicosapentaenoic acid (EPA, 20:5) have been reported to improve metabolic disorders, but their differential effects on anti-obesity under insulin resistance (IR) are still unclear. We fed IR mice with high-fat diet with added 1%, 2%, 4% (w/w) DHA or EPA for 12 weeks. Changes in weight, food intake, white adipose tissue (WAT), liver and blood lipids were assessed. GPR120 and PPARγ of WAT were evaluated to explore the related molecular mechanisms of DHA and EPA for anti-obesity in IR mice. 1%DHA and 1%EPA inhibit adipogenesis by down-regulating GPR120; 4%DHA stimulates browning of WAT and improves IR and inflammatory infiltration by up-regulating PPARγ; 4%EPA exerts its anti-obesity effect by mechanisms independent of PPARγ and GPR120 signaling.