Ellagic acid alleviates paraquat-induced oxidative stress and metabolic disturbances in the muscle of piglets

Oxidative stress disrupts nutrient metabolism and may impair muscle development in piglets. This study investigated whether dietary ellagic acid (EA) supplementation alleviates paraquat (PQ)-induced oxidative stress and metabolic disturbances in the longissimus dorsi muscle of piglets. Piglets were assigned to a control group, a PQ-challenged group, and a PQ-challenged group supplemented with 0.01% EA. PQ challenge did not significantly affect final body weight or average daily gain but impaired antioxidant status, as evidenced by decreased serum total antioxidant capacity and glutathione peroxidase activity and reduced superoxide dismutase and glutathione levels in the longissimus dorsi muscle. EA supplementation significantly increased these four antioxidant indices relative to PQ alone. PQ also decreased the expression of several muscle development-related genes, including MYOD, MYOG, DESMIN, and CAV3 , whereas EA significantly increased CAV3, FOXO1, P21 , and MCP-1 expression relative to PQ alone without significantly altering MYOD, MYOG , or DESMIN . Furthermore, PQ markedly altered the amino acid profile of the longissimus dorsi muscle and reduced the expression of amino acid transporters, including SLC1A1 and SLC6A6 . EA supplementation increased muscle Tau, Glu, Ile, Leu, Phe, and Pro concentrations, increased SLC1A1 and SLC6A6 expression, and decreased PRODH, OAT , and ODC expression relative to PQ alone. PQ challenge also disrupted the long-chain fatty acid profile and suppressed genes involved in fatty acid handling, whereas EA increased FABP3, CD36, and PLIN3 expression and increased C18:3N-3 and C22:1N-9 relative to PQ alone. Overall, these findings suggest that EA may alleviate selected PQ-associated biochemical and metabolic disturbances by improving antioxidant status and modulating muscle amino acid and lipid metabolism.