Please use this identifier to cite or link to this item:
Type: Artigo
Title: Augmentation of insulin secretion by leucine supplementation in malnourished rats: possible involvement of the phosphatidylinositol 3-phosphate kinase/mammalian target protein of rapamycin pathway
Author: Filiputti, Eliane
Rafacho, Alex
Araujo, Eliana P.
Silveira, Leonardo R.
Trevisan, Amon
Batista, Thiago M.
Curi, Rui
Velloso, Licio A.
Quesada, Ivan
Boschero, Antonio C.
Carneiro, Everardo M.
Abstract: A regimen of low-protein diet induces a reduction of pancreatic islet function that is associated with development of metabolic disorders including diabetes and obesity afterward. In the present study, the influence of leucine supplementation on metabolic parameters, insulin secretion to glucose and to amino acids, as well as the levels of proteins that participate in the phosphatidylinositol 3-phosphate kinase (PI3K) pathway was investigated in malnourished rats. Four groups were fed with different diets for 12 weeks: a normal protein diet (17%) without (NP) or with leucine supplementation (NPL) or a low (6%)-protein diet without (LP) or with leucine supplementation (LPL). Leucine was given in the drinking water during the last 4 weeks. As indicated by the intraperitoneal glucose tolerance test, LPL rats exhibited increased glucose tolerance as compared with NPL group. Both NPL and LPL rats had higher circulating insulin levels than controls. The LPL rats also showed increased insulin secretion by pancreatic islets in response to glucose or arginine compared with those observed in islets from LP animals. Glucose oxidation was significantly reduced in NPL, LP, and LPL isolated islets as compared with NP; but no alteration was observed for leucine and glutamate oxidation among the 4 groups. Western blotting analysis demonstrated increased PI3K and mammalian target protein of rapamycin protein contents in LPL compared with LP islets. A significant increase in insulin-induced insulin receptor substrate I associated PI3K activation was also observed in LPL compared with LP islets. These findings indicate that leucine supplementation can augment islet function in malnourished rats and that activation of the PI3K/maminalian target protein of rapamycin pathway may play a role in this process
Subject: Leucina
Country: Estados Unidos
Editor: Elsevier
Rights: Fechado
Identifier DOI: 10.1016/j.metabol.2009.09.007
Date Issue: 2010
Appears in Collections:IB - Artigos e Outros Documentos
FCM - Artigos e Outros Documentos
FENF - Artigos e Outros Documentos

Files in This Item:
File Description SizeFormat 
000277103700004.pdf862.63 kBAdobe PDFView/Open

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.