Fish collagen peptides supplementation ameliorates skeletal muscle injury in high-fat diet mice associated with thyroid function recovery

This study aims to explore the effects of fish collagen peptides (FCP) supplementation on skeletal muscle injury in high-fat (HF) diet mice and their possible mechanisms. Experimental mice were fed a normal diet (4 % fat), HF diet (20 % fat), or FCP diet (20 % fat and 1 % FCPs) for 22 consecutive weeks. Results show that FCP supplementation improves skeletal muscle motor function and histomorphology, and lipid levels; promotes protein synthesis, and inhibits protein degradation in skeletal muscle. Moreover, FCP supplementation also improves mitochondrial biogenesis, promotes energy metabolism and ATP production. Furthermore, FCP supplementation increases antioxidant defenses in the thyroid and skeletal muscle, improves thyroid morphological structure, promotes the synthesis and secretion of thyroid hormones, and enhances the actions of thyroid hormones on its receptor organ skeletal muscle. Cumulatively, these findings indicate that FCP supplementation can alleviate skeletal muscle injury induced by an HF diet associated with thyroid function recovery.