Role of insulin and IGF-I on the regulation of glucose metabolism in European sea bass (Dicentrarchus labrax) fed with different dietary carbohydrate levels

• Type: Article in International Scientific Journal
• Date: 2010

Authors

Enes, P (Author) FCUP; Sanchez Gurmaches, J (Author) Other; Navarro, I (Author) Other; Gutierrez, J (Author) Other; Oliva Teles, A (Author) FCUP

Journal

Title: Comparative biochemistry and physiology. Part A, Molecular & integrative physiology

Vol. 157

Pages: 346-353

ISSN: 1095-6433

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 53 Citations

Scopus - 61 Citations

Scientific classification

FOS: Medical and Health sciences > Basic medicine

Other information

Authenticus ID: P-003-0D6

DOI: 10.1016/j.cbpa.2010.08.006

Abstract (EN): The roles of insulin and insulin-like growth factor-I (IGF-I) in the regulation of glucose metabolism were assessed in European sea bass juveniles fed with distinct dietary carbohydrate levels. Three isonitrogenous diets were formulated to contain 10% (10%PGS) or 30% (30%PGS) pregelatinized starch or no starch (control). The highest plasma glucose and insulin levels were observed 6 h after feeding in fish receiving the 30%PGS diet. Although plasma IGF-I was higher at 6 h than at 24 h after feeding, no effect of dietary carbohydrate level was noticed within each sampling time Increasing dietary carbohydrate level resulted in an increase of liver but not of muscle glycogen content. Hepatic glucokinase (GK) and glucose-6-phosphate dehydrogenase (G6PD) activities increased with the dietary carbohydrate content, whereas pyruvate kinase (PK) activity was higher in fish fed the carbohydrate containing diets than the carbohydrate-free diet. GK activity was higher 6 h than 24 h after feeding, whereas the opposite was observed for G6PD activity. Data suggest that under the nutritional conditions assayed plasma glucose is an insulin secretagogue. Furthermore, insulin appears to have a more important role than IGF-I in stimulating hepatic glucose uptake, thus enhancing GK activity and leading to an increase in liver glycogen content to maintain glucose homeostasis.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 8