| Very low and low density lipoprotein synthesis and secretion by the human hepatoma cell line Hep-G2: effects of free fatty acid. | |
| | |
MedLine Citation:
|
PMID: 3021884 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
The liver is a major source of the plasma lipoproteins; however, direct studies of the regulation of lipoprotein synthesis and secretion by human liver are lacking. Dense monolayers of Hep-G2 cells incorporated radiolabeled precursors into protein ([35S]methionine), cholesterol ([3H]mevalonate and [14C]acetate), triacylglycerol, and phospholipid ([3H]glycerol), and secreted them as lipoproteins. In the absence of free fatty acid in the media, the principal lipoprotein secretory product that accumulated had a density maximum of 1.039 g/ml, similar to serum low density lipoprotein (LDL). ApoB-100 represented greater than 95% of the radiolabeled apoprotein of these particles, with only traces of apoproteins A and E present. Inclusion of 0.8 mM oleic acid in the media resulted in a 54% reduction in radiolabeled triacylglycerol in the LDL fraction and a 324% increase in triacylglycerol in the very low density lipoprotein (VLDL) fraction. Similar changes occurred in the secretion of newly synthesized apoB-100. The VLDL contained apoB-100 as well as apoE. In the absence of exogenous free fatty acid, the radiolabeled cholesterol was recovered in both the LDL and the high density lipoprotein (HDL) regions. Oleic acid caused a 50% decrease in HDL radiolabeled cholesterol and increases of radiolabeled cholesterol in VLDL and LDL. In general, less than 15% of the radiolabeled cholesterol was esterified, despite the presence of cholesteryl ester in the cell. Incubation with oleic acid did not cause an increase in the total amount of radiolabeled lipid or protein secreted. We conclude that human liver-derived cells can secrete distinct VLDL and LDL-like particles, and the relative amounts of these lipoproteins are determined, at least in part, by the availability of free fatty acid. |
| | |
Authors:
|
J L Ellsworth; S K Erickson; A D Cooper |
Related Documents
:
|
1992034 - Metabolic imaging with gallium-68- and indium-111-labeled low-density lipoprotein. 325934 - Induction of lymphocyte proliferation and membrane changes by lipopeptide derivatives o... 3037234 - Comparison of the clearances of serum chylomicron triglycerides enriched with eicosapen... 8902984 - Triglyceride dependence of factor vii coagulant activity in deep venous thrombosis. 19236044 - Synthesis and applications of polyamine amino acid residues: improving the bioactivity ... 6162454 - High affinity of alpha-foetoprotein for arachidonate and other fatty acids. |
Publication Detail:
|
Type: Journal Article; Research Support, U.S. Gov't, P.H.S. |
Journal Detail:
|
Title: Journal of lipid research Volume: 27 ISSN: 0022-2275 ISO Abbreviation: J. Lipid Res. Publication Date: 1986 Aug |
Date Detail:
|
Created Date: 1986-12-17 Completed Date: 1986-12-17 Revised Date: 2007-11-14 |
Medline Journal Info:
|
Nlm Unique ID: 0376606 Medline TA: J Lipid Res Country: UNITED STATES |
Other Details:
|
Languages: eng Pagination: 858-74 Citation Subset: IM |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
Acetates
/
metabolism Apolipoproteins B / biosynthesis Carcinoma, Hepatocellular / metabolism*, secretion Cell Line Humans Kinetics Lipoproteins, LDL / biosynthesis*, secretion Lipoproteins, VLDL / biosynthesis*, secretion Liver / metabolism Liver Neoplasms / metabolism*, secretion Methionine / metabolism Mevalonic Acid / metabolism Oleic Acid Oleic Acids / metabolism Phospholipids / metabolism Serum Albumin, Bovine Triglycerides / metabolism |
| Grant Support | |
ID/Acronym/Agency:
|
AM 18774/AM/NIADDK NIH HHS; AM07294/AM/NIADDK NIH HHS; HL 05360/HL/NHLBI NIH HHS |
| Chemical | |
Reg. No./Substance:
|
0/Acetates; 0/Apolipoproteins B; 0/Lipoproteins, LDL; 0/Lipoproteins, VLDL; 0/Oleic Acids; 0/Phospholipids; 0/Serum Albumin, Bovine; 0/Triglycerides; 112-80-1/Oleic Acid; 150-97-0/Mevalonic Acid; 63-68-3/Methionine |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Transient catecholamine modulation of neutrophil activation: kinetic and intracellular aspects of is...
Next Document: Parameters of cholesterol metabolism in the human hepatoma cell line, Hep-G2.