Unsaturated fatty acids from flaxseed oil and exercise modulate GPR120 but not GPR40 in the liver of obese mice: a new anti-inflammatory approach

摘要

GPR120 and GPR40 were recently reported as omega-3 (omega 3) receptors with anti-inflammatory properties. Physical exercise could increase the expression of these receptors in the liver, improving hepatic metabolism in obesity and type 2 diabetes. Our aim was to investigate GPR120/40 in the liver of lean and obese mice after acute or chronic physical exercise, with or without the supplementation of omega 3 rich flaxseed oil (FS), as well as assess the impact of exercise and FS on insulin signaling and inflammation. Mice were fed a high-fat diet (HF) for 4 weeks to induce obesity and subsequently subjected to exercise with or without FS, or FS alone. Insulin signaling, inflammatory markers and GPR120/40 and related cascades were measured. Chronic, but not acute, exercise and FS increased GPR120, but not GPR40, activating beta-arrestin-2 and decreasing the inflammatory response, as well as reducing fat depots in liver and adipose tissue. Exercise or a source of omega 3 led to a higher tolerance to fatigue and an increased running distance and speed. The combination of physical exercise and omega 3 food sources could provide a new strategy against obesity through the modulation of hepatic GPR120 and an increase in exercise performance. (C) 2018 Elsevier Inc. All rights reserved.