Linked Life Data

11116060

Source:http://linkedlifedata.com/resource/pubmed/id/11116060

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
12
pubmed:dateCreated
2000-12-20
pubmed:abstractText
The apoE knockout (E0) mouse is one of the most widely used animal models of atherosclerosis, and there may be similarities to chylomicron remnant-induced atherosclerosis in humans. Although the lesions of these mice contain large numbers of cholesteryl ester (CE)-laden macrophages (foam cells), E0 plasma lipoproteins are relatively weak inducers of cholesterol esterification in macrophages. Previous in vivo work has suggested that arterial wall sphingomyelinase (SMase) may promote atherogenesis in the E0 mouse, perhaps by inducing subendothelial lipoprotein aggregation and subsequent foam cell formation. The goal of the present study was to test the hypothesis that the modification of E0 lipoproteins by SMase converts these lipoproteins into potent inducers of macrophage foam cell formation. When d<1.063 E0 lipoproteins were pretreated with SMase and then incubated with E0 macrophages, cellular CE mass and stimulation of the cholesterol esterification pathway were increased approximately 5-fold compared with untreated lipoproteins. SMase-treated E0 lipoproteins were more potent stimulators of cholesterol esterification than either E0 lipoproteins in the presence of lipoprotein lipases or oxidized E0 lipoproteins. The uptake and degradation of SMase-treated E0 lipoproteins by macrophages were saturable and specific and substantially inhibited by partial proteolysis of cell-surface proteins. Uptake and degradation were diminished by an anti-apoB antibody and by competition with human S(f) 100-400 hypertriglyceridemic VLDL, raising the possibility that a receptor that recognizes apoB-48 might be involved. In conclusion, SMase-modification of E0 lipoproteins, a process previously shown to occur in lesions, may be an important mechanism for foam cell formation in this widely studied model of atherosclerosis. Moreover, the findings in this report may provide important clues regarding the atherogenicity of chylomicron remnants in humans.
pubmed:grant
pubmed:commentsCorrections
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
1524-4636
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
20
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2607-13
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Sphingomyelinase converts lipoproteins from apolipoprotein E knockout mice into potent inducers of macrophage foam cell formation.
pubmed:affiliation
Department of Medicine, Columbia University, New York, NY 10032, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't