Effects of Vitamin E Supplementation on Growth Performance, Antioxidant Capacity, and Hepatic Lipid Metabolism in Juvenile Chinese Sturgeon (Acipenser sinensis)

This study investigated the effects of vitamin E supplementation on growth performance, antioxidant capacity, and hepatic lipid metabolism in one-year-old juvenile Chinese sturgeon (Acipenser sinensis). A total of 270 fish (initial weight 1.37 ± 0.04 kg) were allocated into 9 fiberglass tanks and fed isonitrogenous and isolipidic diets with graded concentrations of vitamin E (DL-α-tocopherol acetate) including, 0, 1000, and 2000 mg/kg, respectively, for 2 months. Results showed that 1000 mg/kg vitamin E significantly improved growth performance and decreased hepatosomatic index. Dietary vitamin E supplementation significantly reduced the hepatic crude protein and crude lipid levels, withnot significantly affecting moisture and crude ash. Dietary vitamin E led to significant increases in plasma high-density lipoprotein cholesterol and vitamin E levels, while decreasing plasma low-density lipoprotein cholesterol. Additionally, it raised liver vitamin E content and reduced hepatic triglycerides, total cholesterol, crude protein, and crude lipid levels. Vitamin E also significantly downregulated mRNA levels of lipogenesis-related genes (ACC1, acetyl-CoA carboxylase 1; FASN, fatty acid synthase; and PPARγ, peroxisome proliferator activated receptor γ) and inhibited the enzyme activities of ACC1 and FASN, while upregulating lipolysis-related genes (HSL, hormone-sensitive lipase; CPT1, carnitine palmitoyltransferase 1α, and PPARα, peroxisome proliferator activated receptor α) and enhancing the activities of HSL and CPT1α. Furthermore, vitamin E supplementation significantly improved plasma reduced glutathione and superoxide dismutase activities, lowered plasma reactive oxygen species, malondialdehyde levels, and hepatic malondialdehyde contents, and upregulated mRNA levels of hepatic Nrf2 (nuclear factor-erythroid 2 related factor 2), Keap1 (Kelch-like epichlorohydrin associating protein 1), and CuZnSOD (copper/zinc superoxide dismutase). In conclusion, dietary 1000 mg/kg vitamin E supplementation could improve growth performance, enhance antioxidant capacity, and reduce liver fat deposition, indicating its potential as a beneficial dietary additive for promoting health and lipid regulation in juvenile Chinese sturgeon.