Dietary nicotinic acid promotes the growth and tryptophan metabolome of Chinese mitten crab (Eriocheir sinensis) through ACMSD and NADs

Abstract

This paper did research on the effect of dietary nicotinic acid (NA) on lipid metabolism and tryptophan metabolome of Chinese mitten crab (Eriocheir sinensis) to promote its growth. Three diets to administer to E. sinensis (37.25 ± 0.5 g), respectively, for 10 weeks were designed to contain 0% NA (control), 0.02% NA, and 0.10% NA. According to the results, when feeding crabs with 0.02% NA diet, the specific growth rate (SGR) increased markedly while the feed conversion ratio (FCR) was the opposite compared with 0% NA group. The content of total cholesterol (T-CHO) and low-density lipoprotein cholesterol (LDL) in hemolymph decreased significantly when feeding crabs with 0.02% NA diet while the content of high-density lipoprotein cholesterol (HDL) was the opposite. In addition, the relative expression level of microsomal triglyceride transfer protein (mttp) and kynureninase (KFase) decreased significantly in 0.10% NA group while the relative expression level of sterol regulatory element-binding protein 1 (srebp-1) and nicotinamide adenine dinucleotide synthetase (NADs) increased significantly in 0.02% NA group. Meanwhile, the protein expression of 2-amino-3-carboxymuconic semialdehyde decarboxylase (ACMSD) in 0.02% NA group had a very significant increase compared with the other two groups. The result of tryptophan metabolome in hepatopancreas indicates that 0.02% NA in the diet could inhibit the downstream metabolic pathway of tryptophan. According to the results of this research, 0.02% NA in the diet can improve the growth and tryptophan metabolome through ACMSD and NADs, and lipid metabolism is also improved in this group, while 0.10% NA in the diet has no effect on crabs in growth performance.

Keywords

• Nicotinic acid
• Eriocheir sinensis
• Growth performance
• Lipid metabolism
• Tryptophan metabolome