Document Detail


C-reactive protein impairs hepatic insulin sensitivity and insulin signaling in rats: Role of mitogen-activated protein kinases.
MedLine Citation:
PMID:  20967757     Owner:  NLM     Status:  In-Data-Review    
Abstract/OtherAbstract:
Plasma C-reactive protein (CRP) concentration is increased in the metabolic syndrome, which consists of a cluster of cardiovascular disease risk factors, including insulin resistance. It is not known, however, whether CRP is merely a marker of accompanying inflammation or whether it contributes causally to insulin resistance. The objective of this study is to investigate the role that CRP may play in the development of insulin resistance. We examined the effect of single-dose intravenous administration of purified human (h)CRP on insulin sensitivity in Sprague-Dawley rats using the euglycemic, hyperinsulinemic clamp technique. hCRP was associated with impaired insulin suppression of endogenous glucose production with no reduction in peripheral tissue glucose uptake, suggesting that hCRP mediated insulin resistance in the liver but not extrahepatic tissues. We further assessed components of the insulin signaling pathway and mitogen-activated protein kinases (MAPKs) in the liver. Liver tissues derived from hCRP-treated rats showed reduced insulin-stimulated insulin receptor substrate (IRS) tyrosine phosphorylation, IRS/phosphatidylinositol 3-kinase (PI3K) association, and Akt phosphorylation, consistent with hCRP-induced impairment of hepatic insulin signaling. Furthermore, hCRP enhanced phosphorylation of extracellular signal-regulated kinase (ERK)1/2 and p38 MAPK as well as IRS-1 Ser(612) . Finally, we observed in primary cultured rat hepatocytes that U0126 (a selective inhibitor of MAPK/ERK kinase1/2) corrected hCRP-induced impairment of insulin signaling. Conclusions: hCRP plays an active role in inducing hepatic insulin resistance in the rat, at least in part by activating ERK1/2, with downstream impairment in the insulin signaling pathway. (HEPATOLOGY 2011).
Authors:
Liang Xi; Changting Xiao; Robert H J Bandsma; Mark Naples; Khosrow Adeli; Gary F Lewis
Related Documents :
15563957 - Effect of erythropoietin on endothelial cell apoptosis induced by high glucose.
1473267 - Effect of inhibitors and activators of tyrosine kinase on insulin imprinting in tetrahy...
2173567 - Tpa inhibits insulin stimulated pip hydrolysis in fat cell membranes: evidence for modu...
18798337 - Insulin induces calcium signals in the nucleus of rat hepatocytes.
8947867 - Serum fructosamine concentration as an index of glycemia in cats with diabetes mellitus...
11853367 - Mitochondrial 3243 bp mutation: a case report.
Publication Detail:
Type:  Journal Article     Date:  2010-10-21
Journal Detail:
Title:  Hepatology (Baltimore, Md.)     Volume:  53     ISSN:  1527-3350     ISO Abbreviation:  Hepatology     Publication Date:  2011 Jan 
Date Detail:
Created Date:  2011-01-21     Completed Date:  -     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  8302946     Medline TA:  Hepatology     Country:  United States    
Other Details:
Languages:  eng     Pagination:  127-35     Citation Subset:  IM    
Copyright Information:
Copyright © 2010 American Association for the Study of Liver Diseases.
Affiliation:
Department of Medicine and Physiology, University of Toronto, Toronto, Ontario, Canada.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:

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


Previous Document:  MicroRNA silencing of tumor suppressor DLC-1 promotes efficient hepatitis C virus replication in pri...
Next Document:  Adipose triglyceride lipase is a major hepatic lipase that regulates triacylglycerol turnover and fa...