Effects of DGAT1 inhibition on hepatic lipid deposition, antioxidant capacity and inflammatory response in Larimichthys crocea

Abstract Inhibition of diacylglycerol acyltransferase 1 (DGAT1) is an alternative therapeutic strategy for treating fatty liver in mammals. However, the effects of DGAT1 inhibition in fish remain unclear. Here, we found that inhibition of DGAT1 significantly reduced triglyceride (TAG) levels and lipid droplet formation in hepatocytes of large yellow croaker (Larimichthys crocea). Meanwhile, there were no significant effects of DGAT1 specific inhibitors on the cell viability. In addition, inactivation of DGAT1 significantly suppressed the mRNA expression of sterol regulatory element binding protein 1 (srebp1) and fatty acid synthase (fas), and promoted carnitine palmitoyltransferase 1 α (cpt1α) mRNA expression in croaker hepatocytes. After treated with DGAT1 specific inhibitor, expression of catalase (cat) was significantly decreased in hepatocytes under the condition of lipid overload, while glutathione peroxidase (gpx) was significantly increased. However, inhibition of DGAT1 had no significant effects on genes expression related to inflammatory response in croaker hepatocytes. Finally, injection of DGAT1 specific inhibitor into large yellow croaker juveniles showed statistically significant decrease in hepatic TAG contents induced by high fat diet. These results showed that DGAT1 inhibition could significantly alleviate the abnormal deposition of TAG in liver induced by lipid overload in large yellow croaker, which may provide novel therapeutic target for improving the quality control of fish.