Gen Comp Endocrinol 2019 Apr 16. Epub 2019 Apr 16.
Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai 201306, China; Centre for Research on Environmental Ecology and Fish Nutrition of Ministry of Agriculture and Rural Affairs, Shanghai Ocean University, Shanghai 201306, China; National Demonstration Centre for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai 201306, China. Electronic address:
Estradiol is an important sex steroid hormone that involved in regulation of animal lipid metabolism. However, the effect of estradiol on lipid metabolism in swimming crab (Portunus trituberculatus) is unclear. The present study investigated the effect of four concentrations of exogenous estradiol (0, 0.01, 0.1 and 1 μg g crab weight) on the expression levels of lipid metabolism-related genes, lipid composition and histology of hepatopancreas in the P. trituberculatus. The results showed that the mRNA levels of carnitine palmitoyltransferase I and II (CPT-I and CPT-II) increased significantly at the low concentrations (0.01 μg g and 0.1 μg g), while decreased significantly in the highest concentration (1 μg g). The mRNA levels of acyl-CoA oxidase (ACOX), fatty acid transport protein (FATP), fatty acid-binding protein (FABP), diacylglycerol acyltransferase 1 (DGAT1) and acetyl-CoA carboxylase (ACC) were significantly down-regulated. The transcripts of fatty acid synthase (FAS) and fatty acyl desaturase (FAD) decreased significantly only in 1 μg g treatment. All estradiol treatments (0.01, 0.1 and 1 μg g) had significantly higher percentages of 20:4n6, 20:5n3 and 22:6n3, but lower percentages of total monounsaturated fatty acids and polar lipids than the control treatment (0 μg g). Histological observations indicated the size of B cell became larger under estradiol treatment. The results indicated that estradiol promoted lipid catabolism in the hepatopancreas of P. trituberculatus.