Effects of phosphatidylserine supplementation on growth performance, lipid metabolism, antioxidant capacity, and inflammatory response of juvenile large yellow croaker (Larimichthys crocea) fed with high soybean oil diets.

An 8-week experiment was conducted to evaluate the effects of dietary phosphatidylserine (PS) supplementation on juvenile large yellow croaker (Larimichthys crocea) fed high soybean oil (SO) diets. A fish oil control, an SO control, and four SO-based diets supplemented with 0.002%, 0.006%, 0.018%, or 0.054% PS were formulated. Results showed that weight gain exhibited quadratic responses to increasing PS levels. PS supplementation alleviated hepatic lipid deposition and reduced serum and hepatic lipid concentrations. At the molecular level, PS downregulated hepatic lipogenic gene expression including sterol regulatory element-binding protein 1 (srebp1), fatty acid synthase (fas), stearoyl-CoA desaturase 1 (scd1), and acetyl-CoA carboxylase 1 (acc1). Conversely, it upregulated hepatic lipid catabolism genes: peroxisome proliferator-activated receptor a (ppara), lipoprotein lipase (lpl), carnitine palmitoyltransferase 1 (cpt1), and diacylglycerol O-acyltransferase 1 (dgat1). Additionally, PS restored antioxidant enzyme activities and the expression of superoxide dismutase (sod1, sod3), glutathione peroxidase (gpx), and catalase (cat) in the liver. Furthermore, PS reduced hepatic pro-inflammatory cytokine mRNA levels: tumor necrosis factor α(tnf-α), cyclooxygenase 2 (cox-2), and interleukins (il-6, il-1β). In conclusion, dietary inclusion of 0.006%-0.018% PS effectively enhanced growth and antioxidant capacity, altered lipid handling, and affected transcriptional inflammatory responses.