Please use this identifier to cite or link to this item: http://repositorio.unicamp.br/jspui/handle/REPOSIP/198792
Type: Artigo de periódico
Title: Central Leptin Action Improves Skeletal Muscle Akt, Ampk, And Pgc1 Alpha Activation By Hypothalamic Pi3k-dependent Mechanism.
Author: Roman, Erika A F R
Reis, Daniel
Romanatto, Talita
Maimoni, Denis
Ferreira, Eduardo A
Santos, Gustavo A
Torsoni, Adriana S
Velloso, Licio A
Torsoni, Marcio A
Abstract: Central leptin action requires PI3K activity to modulate glucose homeostasis and peripheral metabolism. However, the mechanism behind this phenomenon is not clearly understood. We hypothesize that hypothalamic PI3K activity is important for the modulation of the AMP-activated protein kinase (AMPK)/acetyl-CoA carboxylase (ACC) pathway, PGC1 alpha, and AKT in skeletal muscle (SM). To address this issue, we injected leptin into the lateral ventricle of rats. Hypothalamic JAK2 and AKT were activated by intracerebroventricular (ICV) injection of leptin in a time-dependent manner. Central leptin improved tolerance to glucose (GTT), increased PGC1 alpha expression, and AKT, AMPK, ACC and JAK2 phosphorylation in the soleus muscle. Previous ICV administration of either LY294002 or propranolol (IP) blocked these effects. We concluded that the activation of the hypothalamic PI3K pathway is important for leptin-induced AKT phosphorylation, as well as for active catabolic pathway through AMPK and PGC1 alpha in SM. Thus, a defective leptin signalling PI3K pathway in the hypothalamus may contribute to peripheral resistance to insulin associated to diet-induced obesity.
Subject: Amp-activated Protein Kinases
Adrenergic Beta-antagonists
Animals
Chromones
Energy Metabolism
Glucose
Homeostasis
Hypothalamus
Insulin
Janus Kinase 2
Leptin
Male
Morpholines
Muscle, Skeletal
Phosphatidylinositol 3-kinases
Propranolol
Proto-oncogene Proteins C-akt
Rna-binding Proteins
Rats
Rats, Wistar
Signal Transduction
Transcription Factors
Rights: fechado
Identifier DOI: 10.1016/j.mce.2009.08.007
Address: http://www.ncbi.nlm.nih.gov/pubmed/19698760
Date Issue: 2010
Appears in Collections:Unicamp - Artigos e Outros Documentos

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