Untargeted Metabolomic Characteristics of Skeletal Muscle Dysfunction in Rabbits Induced by a High Fat Diet

Abstract

Background: Type 2 diabetes and metabolic syndrome caused by a high fat diet (HFD) have become public health problems around the world. These diseases are characterized by disrupted mitochondrial oxidation and insulin resistance in skeletal muscle, but the mechanism is not clear. Therefore, this study aims to reveal how a high-fat diet induces skeletal muscle metabolism disorder.Methods：Sixteen weaned rabbits were randomly divided into two groups, one fed with a standard normal diet (SND) and another one fed a HFD for five weeks. Skeletal muscle tissue samples were extracted from each rabbit at the end of the 5-week trial. An untargeted metabolomics profiling was performed using ultraperformance liquid chromatography combined with mass spectrometry (UHPLC-MS/MS).Results: The HFD significantly altered the expression levels of phospholipids, LCACs, histidine, carnosine and tetrahydrocorticosterone in skeletal muscle. Principal component analysis (PCA) and least square discriminant analysis (PLS-DA) indicated that rabbit skeletal muscle metabolism in the HFD group was significantly up-regulated compared with that of the SND group. Among the 43 skeletal muscle metabolites in the HFD group, phospholipids, LCACs, histidine, carnosine and tetrahydrocorticosterone were identified as biomarkers for skeletal muscle metabolic diseases, and may also serve as potential physiological targets for related diseases in the future.Conclusion: The untargeted metabolomics analysis revealed that a HFD altered the rabbit skeletal muscle metabolism of phospholipids, carnitine, amino acids, and steroids. Notably, phospholipids, LCACs, histidine, carnosine and tetrahydrocorticosterone blocked the oxidative ability of mitochondria, and disturbed the oxidative ability of glucose and the fatty acid-glucose cycle in rabbit skeletal muscle.