Document Detail


Chronic ethanol consumption-induced pancreatic {beta}-cell dysfunction and apoptosis through glucokinase nitration and its down-regulation.
MedLine Citation:
PMID:  20855893     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Chronic ethanol consumption is known as an independent risk factor for type 2 diabetes, which is characterized by impaired glucose homeostasis and insulin resistance; however, there is a great deal of controversy concerning the relationships between alcohol consumption and the development of type 2 diabetes. We investigated the effects of chronic ethanol consumption on pancreatic β-cell dysfunction and whether generated peroxynitrite participates in the impaired glucose homeostasis. Here we show that chronic ethanol feeding decreases the ability of pancreatic β-cells to mediate insulin secretion and ATP production in coordination with the decrease of glucokinase, Glut2, and insulin expression. Specific blockade of ATF3 using siRNA or C-terminally deleted ATF3(ΔC) attenuated ethanol-induced pancreatic β-cell apoptosis or dysfunction and restored the down-regulation of glucokinase (GCK), insulin, and pancreatic duodenal homeobox-1 induced by ethanol. GCK inactivation and down-regulation were predominantly mediated by ethanol metabolism-generated peroxynitrite, which were suppressed by the peroxynitrite scavengers N(γ)-monomethyl-L-arginine, uric acid, and deferoxamine but not by the S-nitrosylation inhibitor DTT, indicating that tyrosine nitration is the predominant modification associated with GCK down-regulation and inactivation rather than S-nitrosylation of cysteine. Tyrosine nitration of GCK prevented its association with pBad, and GCK translocation into the mitochondria results in subsequent proteasomal degradation of GCK following ubiquitination. This study identified a novel and efficient pathway by which chronic ethanol consumption may induce GCK down-regulation and inactivation by inducing tyrosine nitration of GCK, resulting in pancreatic β-cell apoptosis and dysfunction. Peroxynitrite-induced ATF3 may also serve as a potent upstream regulator of GCK down-regulation and β-cell apoptosis.
Authors:
Ji Yeon Kim; Eun Hyun Song; Hyun Jung Lee; Yeo Kyoung Oh; Yoon Shin Park; Joo-Won Park; Bong Jo Kim; Dae Jin Kim; Inkyu Lee; Jihyun Song; Won-Ho Kim
Related Documents :
20351753 - A low-risk znt-8 allele (w325) for post-transplantation diabetes mellitus is protective...
17709883 - Chronic oxidative stress as a mechanism for glucose toxicity of the beta cell in type 2...
11347743 - Unchanged incidence of lower-limb amputations in a german city, 1990-1998.
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't     Date:  2010-09-20
Journal Detail:
Title:  The Journal of biological chemistry     Volume:  285     ISSN:  1083-351X     ISO Abbreviation:  J. Biol. Chem.     Publication Date:  2010 Nov 
Date Detail:
Created Date:  2010-11-24     Completed Date:  2010-12-30     Revised Date:  2011-12-21    
Medline Journal Info:
Nlm Unique ID:  2985121R     Medline TA:  J Biol Chem     Country:  United States    
Other Details:
Languages:  eng     Pagination:  37251-62     Citation Subset:  IM    
Affiliation:
Divisions of Metabolic Diseases, National Institutes of Health, Eunpyeong-gu, Seoul 122-701, Korea.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Alcoholism / enzymology*,  genetics,  metabolism,  physiopathology
Animals
Apoptosis*
Cell Line
Disease Models, Animal
Down-Regulation*
Ethanol / adverse effects,  metabolism*
Glucokinase / genetics,  metabolism*
Glucose Transporter Type 2 / genetics,  metabolism
Humans
Insulin-Secreting Cells / cytology*,  enzymology,  metabolism
Male
Mice
Mice, Inbred C57BL
Nitrites / metabolism*
Peroxynitrous Acid / metabolism*
Protein Processing, Post-Translational
Chemical
Reg. No./Substance:
0/Glucose Transporter Type 2; 0/Nitrites; 0/Slc2a2 protein, mouse; 14691-52-2/Peroxynitrous Acid; 64-17-5/Ethanol; EC 2.7.1.2/Glucokinase

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Whole body deletion of AMP-activated protein kinase {beta}2 reduces muscle AMPK activity and exercis...
Next Document:  Potentiation of ligand binding through cooperative effects in monoamine oxidase B.