Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2002-6-17
pubmed:abstractText
Reduction of plasma low density lipoprotein (LDL) levels is associated with a reduced risk of myocardial infarction, stroke, and death. Some of this clinical benefit may be derived from an improvement in endothelium-dependent vasodilation. In the present study, we examined the effects of LDL reduction on cyclooxygenase (COX) activity and prostacyclin (PGI2) production. Human umbilical vein endothelial cells exposed to reduced concentrations of LDL demonstrated increased PGI2 production in a dose-dependent manner (from 0.75+/-0.2 to 2.6+/-0.2 ng/mL, P<0.0001). This alteration in PGI2 production did not result from LDL-induced changes in PGI2 synthase expression. However, selective inhibition of COX-2, but not COX-1, blocked PGI2 production under low cholesterol conditions. Addition of exogenous cholesterol induces dose-dependent reductions in endothelial COX-2 expression as measured by reverse transcription-polymerase chain reaction and by Western blotting. Pretreatment of cells with actinomycin D, a transcription inhibitor, reduced COX-2-derived PGI2 production by 45.9% (from 0.55+/-0.09 to 0.25+/-0.08 ng/mL). Taken together, these observations indicate that endothelial PGI2 production is regulated by cholesterol at the transcriptional level and that cholesterol-sensitive transcriptional pathways that regulate COX-2 expression are present in vascular tissue.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Aspirin, http://linkedlifedata.com/resource/pubmed/chemical/Cholesterol, http://linkedlifedata.com/resource/pubmed/chemical/Cholesterol, LDL, http://linkedlifedata.com/resource/pubmed/chemical/Cyclooxygenase 1, http://linkedlifedata.com/resource/pubmed/chemical/Cyclooxygenase 2, http://linkedlifedata.com/resource/pubmed/chemical/Enzyme Inhibitors, http://linkedlifedata.com/resource/pubmed/chemical/Epoprostenol, http://linkedlifedata.com/resource/pubmed/chemical/Isoenzymes, http://linkedlifedata.com/resource/pubmed/chemical/Membrane Proteins, http://linkedlifedata.com/resource/pubmed/chemical/PTGS1 protein, human, http://linkedlifedata.com/resource/pubmed/chemical/PTGS2 protein, human, http://linkedlifedata.com/resource/pubmed/chemical/Prostaglandin-Endoperoxide Synthases, http://linkedlifedata.com/resource/pubmed/chemical/RNA, Messenger
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
1524-4636
pubmed:author
pubmed:issnType
Electronic
pubmed:day
1
pubmed:volume
22
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
983-8
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
Cyclooxygenase-2-dependent prostacyclin formation is regulated by low density lipoprotein cholesterol in vitro.
pubmed:affiliation
Department of Pharmacology, Vanderbilt University Medical Center, Nashville, Tenn 37232, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't