Influence of a Dietary Vegetable Oil Blend on Serum Lipid Profiles in Large Yellow Croaker ( Larimichthys crocea).

Serum lipid metabolic responses are associated with certain metabolic disorders induced by dietary habits in mammals. However, such associations have not been reported in fish. Lipidomic analyses were performed to investigate fish lipid metabolic responses to a dietary vegetable oil (VO) blend and to elucidate the mechanism of how the dietary VO blend affects serum lipid profiles. Results showed that the dietary VO blend strongly affects serum lipid profiles, especially the ratio of triglyceride/phosphatidylcholine (TAG/PC), via inhibiting hepatic PC biosynthesis and facilitating hepatic and intestinal lipoprotein assembly. Studies in vitro suggested that changes of serum TAG/PC ratio may be partially attributed to altered fatty acid composition in diets. Additionally, the reduction of 16:0/18:1-PC induced by the dietary VO blend may play a role in abnormal lipid deposition through inhibiting PPARA-mediated activation of β-oxidation. These findings suggested that the serum TAG/PC ratio might be a predictive parameter for abnormal lipid metabolism induced by dietary nutrition in fish.