Please use this identifier to cite or link to this item: http://repositorio.unicamp.br/jspui/handle/REPOSIP/194604
Type: Artigo de periódico
Title: Regulation Of Cardiac Jak-2 In Animal Models Of Insulin Resistance.
Author: Rojas, F A
Carvalho, C R
Paez-Espinosa, V
Saad, M J
Abstract: Insulin induces phosphorylation and activation of JAK2 tyrosine, as well as its association with STAT1 and SHP2 in insulin-sensitive tissues of intact rats, thus demonstrating a new pathway in transduction of insulin signals. We investigated this pathway in hearts of rats in three situations of insulin resistance: 72 h of fasting, chronic treatment with dexamethasone, and acute treatment with epinephrine. The acute treatment with epinephrine showed no difference in insulin-induced JAK2 tyrosine phosphorylation or JAK2/STAT1 and JAK2/SHP2 association in comparison with the control. In fasted rats the JAK2 protein concentration decreased, accompanied by a decrease in the stoichiometry of the phosphorylation to 70%, an increase in association of JAK2/STAT1 to 160%, and a decrease in JAK2/SHP2 association to 85%. In the dexamethasone-treated group, the JAK2 protein concentrations increased but the stoichiometry of its phosphorylation decreased to 20%, whereas the JAK2/STAT1 and JAK2/SHP2 associations changed by 70% and 170%, respectively. In fasting and dexamethasone-treated rats, therefore, insulin-induced JAK2 tyrosine phosphorylation decreases, and the JAK2 protein expression is differentially regulated such that the insulin-induced JAK2 association with SHP2 and STAT1 shows opposite interactions with the kinase.
Subject: Animals
Dna-binding Proteins
Dexamethasone
Enzyme Activation
Epinephrine
Fasting
Insulin Resistance
Intracellular Signaling Peptides And Proteins
Janus Kinase 2
Male
Myocardium
Phosphorylation
Protein Tyrosine Phosphatase, Non-receptor Type 11
Protein Tyrosine Phosphatase, Non-receptor Type 6
Protein Tyrosine Phosphatases
Protein-tyrosine Kinases
Proto-oncogene Proteins
Rats
Rats, Wistar
Stat1 Transcription Factor
Signal Transduction
Trans-activators
Tyrosine
Rights: fechado
Identifier DOI: 10.1080/15216540050167043
Address: http://www.ncbi.nlm.nih.gov/pubmed/11032244
Date Issue: 2000
Appears in Collections:Artigos e Materiais de Revistas Científicas - Unicamp

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