Linked Life Data

15105424

Source:http://linkedlifedata.com/resource/pubmed/id/15105424

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
26
pubmed:dateCreated
2004-6-21
pubmed:abstractText
Cholesteryl esters are selectively removed from high density lipoproteins by hepatocytes and steroidogenic cells through a process mediated by scavenger receptor BI. In the liver this cholesterol is secreted into bile, primarily as free cholesterol. Previous work showed that carboxyl ester lipase enhanced selective uptake of cholesteryl ether from high density lipoprotein by an unknown mechanism. Experiments were performed to determine whether carboxyl ester lipase plays a role in scavenger receptor BI-mediated selective uptake. When added to cultures of HepG2 cells, carboxyl ester lipase cofractionated with scavenger receptor BI and [(3)H]cholesteryl ether-labeled high density lipoprotein in lipid raft fractions of cell homogenates. Confocal microscopy of immunostained carboxyl ester lipase and scavenger receptor BI showed a close association of these proteins in HepG2 cells. The enzyme and receptor also cofractionated from homogenates of mouse liver using two different fractionation methods. Antibodies that block scavenger receptor BI function prevented carboxyl ester lipase stimulation of selective uptake in primary hepatocytes from carboxyl ester lipase knockout mice. Heparin blockage of cell-surface proteoglycans also prevented carboxyl ester lipase stimulation of cholesteryl ester uptake by HepG2 cells. Inhibition of carboxyl ester lipase activity in HepG2 cells reduced hydrolysis of high density lipoprotein-cholesteryl esters approximately 40%. In vivo, hydrolysis was similarly reduced in lipid rafts from the livers of carboxyl ester lipase-null mice compared with control animals. Primary hepatocytes from these mice yielded similar results. The data suggest that carboxyl ester lipase plays a physiological role in hepatic selective uptake and metabolism of high density lipoprotein cholesteryl esters by direct and indirect interactions with the scavenger receptor BI pathway.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
25
pubmed:volume
279
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
27599-606
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:15105424-Animals, pubmed-meshheading:15105424-Carboxylesterase, pubmed-meshheading:15105424-Cell Line, Tumor, pubmed-meshheading:15105424-Cell Membrane, pubmed-meshheading:15105424-Chemical Fractionation, pubmed-meshheading:15105424-Cholesterol Esters, pubmed-meshheading:15105424-Endosomes, pubmed-meshheading:15105424-Heparin, pubmed-meshheading:15105424-Hepatocytes, pubmed-meshheading:15105424-Humans, pubmed-meshheading:15105424-Hydrolysis, pubmed-meshheading:15105424-Lipoproteins, HDL, pubmed-meshheading:15105424-Liver, pubmed-meshheading:15105424-Membrane Microdomains, pubmed-meshheading:15105424-Mice, pubmed-meshheading:15105424-Mice, Knockout, pubmed-meshheading:15105424-Receptors, Immunologic, pubmed-meshheading:15105424-Receptors, Scavenger, pubmed-meshheading:15105424-Taurocholic Acid, pubmed-meshheading:15105424-Taurodeoxycholic Acid
pubmed:year
2004
pubmed:articleTitle
Carboxyl ester lipase cofractionates with scavenger receptor BI in hepatocyte lipid rafts and enhances selective uptake and hydrolysis of cholesteryl esters from HDL3.
pubmed:affiliation
Department of Pathology North, University of Cincinnati College of Medicine, Cincinnati, Ohio 45237, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't