This study explored the metabolic effects of branched-chain amino acids (BCAAs) on the hepatocytes of spotted seabass (Lateolabrax maculatus) under high-glucose (HG) or high-fat (HF) conditions. Hepatocytes were cultured under five different conditions: control, high glucose (HG), HG + BCAAs (Leu 0.8 mM, Ile 0.4 mM, Val 0.8 mM), high fat (HF), and HF + BCAAs (Leu 0.8 mM, Ile 0.8 mM, Val 0.8 mM). After 72 h of culture, cells and cell supernatants were collected to measure relevant indicators. The results revealed that BCAAs supplementation significantly reduced glycogen and lipid accumulation in hepatocytes exposed to HG or HF conditions (p < 0.05). Additionally, alanine aminotransferase and aspartate aminotransferase activities in the supernatant were significantly decreased, indicating that BCAAs supplementation alleviated hepatocyte damage induced by these conditions. Furthermore, BCAAs addition markedly enhanced antioxidant defense by increasing superoxide dismutase and catalase activities, improving total antioxidant capacity, and reducing malondialdehyde levels. Metabolic enzyme activity analysis revealed that BCAAs significantly increased the activities of citrate synthase (CS), alpha-ketoglutarate dehydrogenase complex (α-KGDHC), succinate dehydrogenase (SDH), phosphoenolpyruvate carboxykinase (PEPCK), and liver pyruvate kinase (LPS), while significantly decreasing fatty acid synthase (FAS) activity. Gene expression analysis further demonstrated that BCAAs supplementation downregulated the expression of lipogenic genes (fas and srebp-1c) and upregulated the expression of lipolytic genes (ppaα and atgl) and glucose metabolism-related genes (g6pd, hk, pfk, pk, fbp, and g6pase). Under HG or HF conditions, hepatocytes exhibited decreased adenosine triphosphate (ATP) content, increased reactive oxygen species (ROS) levels, and reduced mitochondrial membrane potential. These adverse effects were mitigated by BCAAs supplementation. In conclusion, BCAAs supplementation alleviated hepatocyte damage caused by HG or HF conditions, enhanced antioxidant defenses, and protected mitochondrial activity and function by promoting glucose and lipid metabolism.

This study explored the metabolic effects of branched-chain amino acids (BCAAs) on the hepatocytes of spotted seabass (Lateolabrax maculatus) under high-glucose (HG) or high-fat (HF) conditions. Hepatocytes were cultured under five different conditions: control, high glucose (HG), HG + BCAAs (Leu 0.8 mM, Ile 0.4 mM, Val 0.8 mM), high fat (HF), and HF + BCAAs (Leu 0.8 mM, Ile 0.8 mM, Val 0.8 mM). After 72 hours of culture, cells and cell supernatants were collected to measure relevant indicators. The results revealed that BCAAs supplementation significantly reduced glycogen and lipid accumulation in hepatocytes exposed to high-glucose or high-fat conditions (P<0.05). Additionally, alanine aminotransferase and aspartate aminotransferase activities in the supernatant were significantly decreased, indicating that BCAAs alleviated hepatocyte damage induced by these conditions. Furthermore, BCAAs addition markedly enhanced antioxidant activity by increasing superoxide dismutase and catalase activity, improving total antioxidant capacity, and reducing malondialdehyde levels. These findings suggest that BCAAs improve antioxidant defenses in hepatocytes under high-glucose or high-fat loads. Metabolic enzyme activity analysis revealed that BCAAs significantly increased the activities of citrate synthase (CS), alpha-ketoglutarate dehydrogenase complex (α-KGDHC), succinate dehydrogenase (SDH), phosphoenolpyruvate carboxykinase (PEPCK) and liver pyruvate kinase (LPS), while significantly decreasing fatty acid synthase (FAS) activity. Gene expression analysis further demonstrated that BCAAs supplementation downregulated the expression of lipogenic genes (fas and srebp-1c), and upregulating the expression of lipolytic genes (ppaα and atgl) as well as glucose metabolism-related genes (g6pd, hk, pfk, pk, fbp, and g6pase). Under high-glucose or high-fat conditions, hepatocytes exhibited decreased adenosine triphosphate (ATP) content, increased reactive oxygen species (ROS) levels, and reduced mitochondrial membrane potential. These adverse effects were mitigated by BCAAs supplementation. In conclusion, BCAAs supplementation alleviated hepatocyte damage caused by high-glucose or high-fat conditions, enhanced antioxidant defenses, and protected mitochondrial activity and function by promoting glucose and lipid metabolism.