Please use this identifier to cite or link to this item: http://repositorio.unicamp.br/jspui/handle/REPOSIP/78926
Type: Artigo de periódico
Title: Cold-induced PGC-1 alpha expression modulates muscle glucose uptake through an insulin receptor/Akt-independent, AMPK-dependent pathway
Author: Oliveira, RLGS
Ueno, M
de Souza, CT
Pereira-da-Silva, M
Gasparetti, AL
Bezzera, RMN
Alberici, LC
Vercesi, AE
Saad, MJA
Velloso, LA
Abstract: Peroxisome proliferator-activated receptor-gamma coactivator-1alpha (PGC-1alpha) participates in control of expression of genes involved in adaptive thermogenesis, muscle fiber type differentiation, and fuel homeostasis. The objective of the present study was to evaluate the participation of cold-induced PGC-1alpha expression in muscle fiber type-specific activity of proteins that belong to the insulin-signaling pathway. Rats were exposed to 4degreesC for 4 days and acutely treated with insulin in the presence or absence of an antisense oligonucleotide to PGC-1alpha. Cold exposure promoted a significant increase of PGC-1alpha and uncoupling protein-3 protein expression in type I and type II fibers of gastrocnemius muscle. In addition, cold exposure led to higher glucose uptake during a hyperinsulinemic clamp, which was accompanied by higher expression and membrane localization of GLUT4 in both muscle fiber types. Cold exposure promoted significantly lower insulin-induced tyrosine phosphorylation of the insulin receptor (IR) and Ser(473) phosphorylation of acute transforming retrovirus thymoma (Akt) and an insulin-independent increase of Thr(172) phosphorylation of adenosine 5'-monophosphate-activated protein kinase (AMPK). Inhibition of PGC-1alpha expression in cold-exposed rats by antisense oligonucleotide treatment diminished glucose clearance rates during a hyperinsulinemic clamp and reduced expression and membrane localization of GLUT4. Reduction of PGC-1alpha expression resulted in no modification of insulin-induced tyrosine phosphorylation of the IR and Ser(473) phosphorylation of Akt. Finally, reduction of PGC-1alpha resulted in lower Thr(172) phosphorylation of AMPK. Thus cold-induced hyperexpression of PGC-1alpha participates in control of skeletal muscle glucose uptake through a mechanism that controls GLUT4 expression and subcellular localization independent of the IR and Akt activities but dependent on AMPK.
Subject: acute transforming retrovirus thymoma
adenosine 5 '-monophosphate-activated protein kinase
cold exposure
Country: EUA
Editor: Amer Physiological Soc
Rights: embargo
Identifier DOI: 10.1152/ajpendo.00103.2004
Date Issue: 2004
Appears in Collections:Unicamp - Artigos e Outros Documentos

Files in This Item:
File Description SizeFormat 
WOS000223791400013.pdf474.85 kBAdobe PDFView/Open


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