Sugano_2006_J.Neurochem_98_20

Reference

Title : Enhancement of insulin-induced PI3K\/Akt\/GSK-3beta and ERK signaling by neuronal nicotinic receptor\/PKC-alpha\/ERK pathway: up-regulation of IRS-1\/-2 mRNA and protein in adrenal chromaffin cells - Sugano_2006_J.Neurochem_98_20
Author(s) : Sugano T , Yanagita T , Yokoo H , Satoh S , Kobayashi H , Wada A
Ref : Journal of Neurochemistry , 98 :20 , 2006
Abstract :

In cultured bovine adrenal chromaffin cells treated with nicotine (10 microm for 24 h), phosphorylation of Akt, glycogen synthase kinase-3beta (GSK-3beta) and extracellular signal-regulated kinase (ERK)1/2 induced by insulin (100 nm for 10 min) was enhanced by approximately 62%, without altering levels of these protein kinases. Nicotine produced time (> 12 h)- and concentration (EC(50) 3.6 and 13 microm)-dependent increases in insulin receptor substrate (IRS)-1 and IRS-2 levels by approximately 125 and 105%, without altering cell surface density of insulin receptors. In these cells, insulin-induced tyrosine phosphorylation of IRS-1/IRS-2 and recruitment of phosphoinositide 3-kinase (PI3K) to IRS-1/IRS-2 were augmented by approximately 63%. The increase in IRS-1/IRS-2 levels induced by nicotine was prevented by nicotinic acetylcholine receptor (nAChR) antagonists, the Ca(2+) chelator 1,2-bis(2-aminophenoxy)-ethane-N,N,N',N'-tetra-acetic acid tetrakis-acetoxymethyl ester, cycloheximide or actinomycin D. Nicotine increased IRS-1 and IRS-2 mRNA levels by approximately 57 and approximately 50%, and this was prevented by conventional protein kinase C (cPKC) inhibitor Go6976, or ERK kinase inhibitors PD98059 and U0126. Nicotine phosphorylated cPKC-alpha, thereby increasing phosphorylation of ERK1/ERK2, as demonstrated by using Go6976, PD98059 or U0126. Selective activation of cPKC-alpha by thymeleatoxin mimicked these effects of nicotine. Thus, stimulation of nAChRs up-regulated expression of IRS-1/IRS-2 via Ca(2+)-dependent sequential activation of cPKC-alpha and ERK, and enhanced insulin-induced PI3K/Akt/GSK-3beta and ERK signaling pathways.

PubMedSearch : Sugano_2006_J.Neurochem_98_20
PubMedID: 16805793

Related information

Citations formats

Sugano T, Yanagita T, Yokoo H, Satoh S, Kobayashi H, Wada A (2006)
Enhancement of insulin-induced PI3K\/Akt\/GSK-3beta and ERK signaling by neuronal nicotinic receptor\/PKC-alpha\/ERK pathway: up-regulation of IRS-1\/-2 mRNA and protein in adrenal chromaffin cells
Journal of Neurochemistry 98 :20

Sugano T, Yanagita T, Yokoo H, Satoh S, Kobayashi H, Wada A (2006)
Journal of Neurochemistry 98 :20