Document Detail


Acute suppression of apo B secretion by insulin occurs independently of MTP.
MedLine Citation:
PMID:  21316344     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Secretion of apolipoprotein (apo) B-containing lipoproteins by the liver depends mainly upon apo B availability and microsomal triglyceride transfer protein (MTP) activity and is subject to insulin regulation. Hepatic MTP mRNA expression is negatively regulated by insulin which correlates with inhibition of apo B secretion suggesting that insulin might suppress apo B secretion through an MTP-dependent mechanism. To investigate this possibility, we examined the acute effect of insulin on hepatic MTP expression and activity levels in vivo utilizing apobec-1(-/-) mice. Insulin did not significantly alter hepatic MTP mRNA levels or lipid transfer activity 2h following injection, but suppressed expression of genes important in gluconeogenesis. To study the specific role of MTP, we expressed human MTP (hMTP) in primary rat hepatocytes using adenoviral gene transfer. Increased expression of hMTP resulted in a 47.6±17.9% increase in total apo B secreted. Incubation of hepatocytes with insulin suppressed apo B secretion by 50.1±10.8% in cells over-expressing hMTP and by 53.0±12.4% in control transfected hepatocytes. Results indicate that even under conditions of increased hepatic apo B secretion mediated by MTP, responsiveness of hepatocytes to insulin to suppress apo B secretion is maintained.
Authors:
Janet D Sparks; Jeffrey M Chamberlain; Colleen O'Dell; Irani Khatun; M Mahmood Hussain; Charles E Sparks
Related Documents :
25343274 - Increased adrenergic signaling is responsible for decreased glucose-stimulated insulin ...
2479064 - The perfused porcine pancreas as a model for testing organ protective solutions.
6993264 - Plasma c-peptide and serum insulin antibodies in diabetic patients receiving pancreatic...
22377714 - Impact of common type 2 diabetes risk gene variants on future type 2 diabetes in the no...
6231704 - The effect of streptozotocin and streptozotocin-induced diabetes on the kidney.
6342324 - Relation between plasma insulin and blood glucose in a cross-sectional population study...
Publication Detail:
Type:  Journal Article; Research Support, N.I.H., Extramural; Research Support, Non-U.S. Gov't     Date:  2011-02-18
Journal Detail:
Title:  Biochemical and biophysical research communications     Volume:  406     ISSN:  1090-2104     ISO Abbreviation:  Biochem. Biophys. Res. Commun.     Publication Date:  2011 Mar 
Date Detail:
Created Date:  2011-03-14     Completed Date:  2011-05-05     Revised Date:  2014-09-14    
Medline Journal Info:
Nlm Unique ID:  0372516     Medline TA:  Biochem Biophys Res Commun     Country:  United States    
Other Details:
Languages:  eng     Pagination:  252-6     Citation Subset:  IM    
Copyright Information:
Copyright © 2011 Elsevier Inc. All rights reserved.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Adenoviridae
Animals
Apolipoproteins B / metabolism*
Carrier Proteins / genetics,  metabolism*
Cells, Cultured
Humans
Insulin / pharmacology,  physiology*
Lipoproteins, VLDL / metabolism*
Liver / drug effects,  metabolism*
Male
Mice
Mice, Mutant Strains
RNA, Messenger / metabolism
Rats
Rats, Sprague-Dawley
Transfection
Grant Support
ID/Acronym/Agency:
DK078131/DK/NIDDK NIH HHS; DK46900/DK/NIDDK NIH HHS; R01 DK078131/DK/NIDDK NIH HHS; R01 DK078131-02S1/DK/NIDDK NIH HHS; R01 DK078131-03/DK/NIDDK NIH HHS
Chemical
Reg. No./Substance:
0/Apolipoproteins B; 0/Carrier Proteins; 0/Insulin; 0/Lipoproteins, VLDL; 0/RNA, Messenger; 0/microsomal triglyceride transfer protein
Comments/Corrections

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


Previous Document:  Sindbis virus replication, is insensitive to rapamycin and torin1, and suppresses Akt/mTOR pathway l...
Next Document:  Involvement of Rac GTPase activation in phosphatidylcholine hydroperoxide-induced THP-1 cell adhesio...