Fish oil enriched 6)-3 fatty acids ameliorates protein synthesis/degradation imbalance, inflammation, and wasting in muscles of diet-induced obese rats

Abstract

We investigated the effects of long-term supplementation of omega-3 fatty acids-enriched fish oil (FO) on preserving muscle mass. We found that dietary supplementation with 5% FO has a direct impact on preventing obesity and skeletal muscle loss in rats fed a high-fat diet for 16 weeks. The increased protein expression for ubiquitin ligases atrogin-1 and muscle RING-finger protein 1 (MuRF1) and the autophagy-related protein, PTENinduced putative kinase 1 (PINK1) in muscles were both abrogated by FO. The AKT and mammalian target of rapamycin (mTOR) phosphorylation and the AMP-activated protein kinase (AMPK)/peroxisome proliferatoractivated receptor gamma coactivator 1 alpha (PGC-1 alpha) signaling activation in muscles were up-regulated by FO. FO supplementation effectively reversed the increased plasma TNF-alpha levels and NF-Kappa B activation in muscles. These results suggest that FO supplementation prevents skeletal muscle wasting under obesity through activating AKT/ mTOR and AMPK/PGC-1 alpha signals and blocking NF-Kappa B-mediated inflammatory pathway to improve the balance between protein synthesis and degradation.