Influence of dietary carbohydrate level on endocrine status and hepatic carbohydrate metabolism in the marine fish Sparus sarba
Publication in refereed journal


摘要Silver sea bream, Sparus sarba, were fed two diets of different carbohydrate levels (2 and 20% dextrin) for 4 weeks, and the effects on organ indices, liver composition, serum metabolite and hormone levels and gene expression profile of key enzymes of carbohydrate metabolism in the liver were investigated. By using real-time PCR, mRNA expression levels of carbohydrate metabolic enzymes including glucokinase (GK, glycolysis), glucose-6-phosphatase (G6Pase, gluconeogenesis), glycogen synthase (GS, glycogenesis), glycogen phosphorylase (GP, glycogenolysis) and glucose-6-phosphate dehydrogenase (G6PDH, pentose phosphate pathway) in liver of sea bream have been examined, and it was found that high dietary carbohydrate level increased mRNA level of GK but decreased mRNA levels of G6Pase and GP. However, mRNA levels of GS and G6PDH were not significantly influenced by dietary carbohydrate. Silver sea bream fed high dietary carbohydrate had higher hepatosomatic index (HSI), liver glycogen and protein, but there were no significant changes in gonadosomatic index (GSI), serum glucose and protein level, as well as liver lipid and moisture level. Pituitary growth hormone (GH) and hepatic insulin-like growth factor I (IGF-I) transcript abundance were assayed by real-time PCR, and it was found that both parameters remained unchanged in fish fed different dietary carbohydrate levels. Serum triiodothyronine (T-3) and thyroxine (T-4) were not significantly affected by dietary carbohydrate levels, but lower serum cortisol level was found in fish fed high dietary carbohydrate level. These results suggest that silver sea bream is able to adapt to a diet with high carbohydrate content (up to 20% dextrin), the consumption of which would lead to fundamental reorganization of carbohydrate metabolism resulting in hepatic glycogen deposition.
著者Leung LY, Woo NYS
期刊名稱Fish Physiology and Biochemistry
頁次543 - 554
關鍵詞Carbohydrate metabolic enzymes; Dietary carbohydrate; Gene expression; Hormones
Web of Science 學科類別Biochemistry & Molecular Biology; BIOCHEMISTRY & MOLECULAR BIOLOGY; Fisheries; FISHERIES; Physiology; PHYSIOLOGY

上次更新時間 2021-11-10 於 00:06