PSIV-B-35 Late-Breaking: Integrating target metabolomic and global proteomic analyses reveals a selenium shift energy metabolism by regulating the redox state in skeletal muscle of pigs

Abstract

Abstract Selenium (Se) is involved in the synthesis of 25 mammal selenoproteins, most of which are oxidation enzymes. Energy metabolism is a major mechanism of power reduction needed to maintain the redox state. Whether energy metabolism in pig skeletal muscle is shifted by the Se-mediated redox state remains unclear. In this study, integrated target metabolomic and global proteomic analyses were used to study how skeletal muscle energy metabolism shifts in response to dietary Se. Twenty-four Yorkshire male pigs (12.50 ± 1.32 kg) were fed a basal diet (Se deficiency, Se-D, 0.007 mg Se/kg) or a basal diet supplemented with selenomethionine (Se adequate, Se-A, 0.3 mg Se/kg) for 16 weeks. Animals were then scarified and their longissimus dorsi were sampled for meat quality, Se content, redox state, selenotranscriptome, global proteomics, and energy-targeted metabolomic profile analysis. Longissimus dorsi water holding capacity in the Se-D group was significantly decreased (P < 0.001). Se content in the Se-D group (0.02 ± 0.003 mg Se/kg) was significantly lower (P < 0.001) than that in the Se-A group (0.48 ± 0.03 mg Se/kg). A total of 15 selenoprotein mRNA levels were significantly affected (P < 0.05), in which 13 were downregulated and two were upregulated in the Se-D group. Compared to those in the Se-A group, the glutathione peroxidase and thioredoxin reductase activity, as well as the total antioxidant capacity were significantly decreased (P < 0.05), while the MDA levels were significantly increased (P < 0.001) in the Se-D group. The metabolomic and proteomic analyses showed significantly increased (P < 0.05) levels of glucose-6-phosphate, phosphoenolpyruvate, pyruvic acid, lactic acid, phosphoglucomutase-1, glucose-6-phosphate isomerase, glyceraldehyde-3-phosphate dehydrogenase, and lactic dehydrogenase in the Se-D group compared to those in the Se-A group. These results indicated that Se can regulate glycolysis by modulating the redox state in skeletal muscle of pigs.