Document Detail

Reversible accumulation of cholesteryl esters in macrophages incubated with acetylated lipoproteins.
Jump to Full Text
MedLine Citation:
PMID:  229107     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Mouse peritoneal macrophages accumulate large amounts of cholesteryl ester when incubated with human low-density lipoprotein that has been modified by chemical acetylation (acetyl-LDL). This accumulation is related to a high-affinity cell surface binding site that mediates the uptake of acetyl-LDL by adsorptive endocytosis and its delivery to lysosomes. The current studies demonstrate that the cholesteryl ester accumulation can be considered in terms of a two-compartment model: (a) the incoming cholesteryl esters of acetyl-LDL are hydrolyzed in lysosomes, and (b) the resultant free cholesterol is re-esterified in the cytosol where the newly formed esters are stored as lipid droplets. The following biochemical and morphologic evidence supports the hydrolysis-re-esterification mechanism: (a) Incubation of macrophages with acetyl-LDL markedly increased the rate of cholesteryl ester synthesis from [14C]oleate, and this was accompanied by an increase in the acyl-CoA:cholesteryl acyltransferase activity of cell-free extracts. (b) When macrophages were incubated with reconstituted acetyl-LDL in which the endogenous cholesterol was replaced with [3H]-cholesteryl linoleate, the [3H]cholesteryl linoleate was hydrolyzed, and at least one-half of the resultant [3H]cholesterol was re-esterified to form [3H]cholesteryl oleate, which accumulated within the cell. The lysosomal enzyme inhibitor chloroquine inhibited the hydrolysis of the [3H]cholesteryl linoleate, thus preventing the formation of [3H]cholesteryl oleate and leading to the accumulation of unhydrolyzed [3H]cholesteryl linoleate within the cells. (c) In the electron microscope, macrophages incubated with acetyl-LDL had numerous cytoplasmic lipid droplets that were not surrounded by a limiting membrane. The time course of droplet accumulation was similar to the time course of cholesteryl ester accumulation as measured biochemically. (d) When acetyl-LDL was removed from the incubation medium, biochemical and morphological studies showed that cytoplasmic cholesteryl esters were rapidly hydrolyzed and that the resultant free cholesterol was excreted from the cell.
Authors:
M S Brown; J L Goldstein; M Krieger; Y K Ho; R G Anderson
Related Documents :
11895447 - Differential effects of ergosterol and cholesterol on cdk1 activation and sre-driven tr...
9300777 - Overexpression of hormone-sensitive lipase in chinese hamster ovary cells leads to abno...
22850537 - Spot identification and quality control in cell-based microarrays.
11530237 - Degeneration of neurons and glia in the niemann-pick c mouse is unrelated to the low-de...
23510487 - Hydrothermally grown upright-standing nanoporous nanosheets of iodine-doped zno (zno:i)...
22718197 - Rapid image-based cytometry for comparison of fluorescent viability staining methods.
Publication Detail:
Type:  Journal Article; Research Support, U.S. Gov't, P.H.S.    
Journal Detail:
Title:  The Journal of cell biology     Volume:  82     ISSN:  0021-9525     ISO Abbreviation:  J. Cell Biol.     Publication Date:  1979 Sep 
Date Detail:
Created Date:  1980-02-28     Completed Date:  1980-02-28     Revised Date:  2014-06-27    
Medline Journal Info:
Nlm Unique ID:  0375356     Medline TA:  J Cell Biol     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  597-613     Citation Subset:  IM    
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Acetylation
Animals
Ascitic Fluid / cytology
Cholesterol Esters / metabolism*
Culture Techniques
Female
Humans
Hydrolysis
Inclusion Bodies / ultrastructure
Lipids
Lipoproteins, LDL / metabolism*
Lysosomes / metabolism
Macrophages / metabolism*,  ultrastructure
Mice
Grant Support
ID/Acronym/Agency:
P01 HL020948/HL/NHLBI NIH HHS
Chemical
Reg. No./Substance:
0/Cholesterol Esters; 0/Lipids; 0/Lipoproteins, LDL
Comments/Corrections

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

Full Text
Journal Information
Journal ID (nlm-ta): J Cell Biol
ISSN: 0021-9525
ISSN: 1540-8140
Publisher: The Rockefeller University Press
Article Information
Download PDF

Print publication date: Day: 1 Month: 9 Year: 1979
Volume: 82 Issue: 3
First Page: 597 Last Page: 613
ID: 2110476
Publisher Id: 80072214
PubMed Id: 229107

Reversible accumulation of cholesteryl esters in macrophages incubated with acetylated lipoproteins


Article Categories:
  • Articles


Previous Document:  Induction of new-bone formation in the host bed by human bone-tumor transplants in athymic nude mice...
Next Document:  Isolation of human platelet plasma membranes with polylysine beads.