Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2005-4-20
pubmed:abstractText
Prostacyclin (PGI(2)) has beneficial cytoprotective properties, is a potent inhibitor of platelet aggregation and has been reported to improve microcirculatory blood flow during sepsis. The formation of PGI(2) in response to proinflammatory cytokines is catalysed by the inducible cyclooxygenase (COX) isoform COX-2. Recombinant human activated protein C (rhAPC, drotrecogin alfa (activated)) was shown to have multiple biological activities in vitro and to promote resolution of organ dysfunction in septic patients. Whether rhAPC exerts its beneficial effects by modulating prostanoid generation is unknown up to now. It was therefore the aim of the study to examine the in vitro effect of rhAPC on COX-2-mRNA-expression and PGI(2) release from human umbilical vein endothelial cells (HUVEC). We found that rhAPC, at supra-therapeutical concentrations (500 ng/ml-20 microg/ml), upregulated the amount of COX-2-mRNA in HUVEC at t=3-9 h and caused a time- and dose-dependent release of 6-keto PGF(1 alpha), the stable hydrolysis product of prostacyclin. RhAPC further increased the stimulating effect of tumor necrosis factor-alpha (TNF-alpha) and thrombin on COX-2-mRNA-levels. Transcript levels of cyclooxygenase-1 (COX-1) and prostaglandin 12 synthase, however, were unaffected by the stimulation with rhAPC or thrombin. The upregulatory effect on COX2-mRNA levels was specific for rhAPC since the zymogen protein C in equimolar concentrations had no effect on COX-2-mRNA-levels or 6-keto PGF(1 alpha)-release. Western Blot analysis revealed an increase of COX-2-protein content in HUVEC after treatment with rhAPC. As shown by experiments using monoclonal antibodies against the thrombin receptor PAR-1 (mAb=ATAP2) and against the endothelial protein C receptor (EPCR; mAb=RCR-252), the effect of rhAPC on COX-2-mRNA upregulation was mediated by binding to the EPCR-receptor and signaling via PAR-1. These results demonstrate that induction of COX-2-expression is an important response of HUVEC to stimulation with rhAPC and may represent a new molecular mechanism, by which rhAPC promotes upregulation of prostanoid production in human endothelium.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Blood Coagulation Factors, http://linkedlifedata.com/resource/pubmed/chemical/Cyclooxygenase 2, http://linkedlifedata.com/resource/pubmed/chemical/Epoprostenol, http://linkedlifedata.com/resource/pubmed/chemical/Membrane Proteins, http://linkedlifedata.com/resource/pubmed/chemical/PTGS2 protein, human, http://linkedlifedata.com/resource/pubmed/chemical/Prostaglandin-Endoperoxide Synthases, http://linkedlifedata.com/resource/pubmed/chemical/Prostaglandins, http://linkedlifedata.com/resource/pubmed/chemical/Protein C, http://linkedlifedata.com/resource/pubmed/chemical/RNA, Messenger, http://linkedlifedata.com/resource/pubmed/chemical/Receptor, PAR-1, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Cell Surface, http://linkedlifedata.com/resource/pubmed/chemical/Recombinant Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Thrombin, http://linkedlifedata.com/resource/pubmed/chemical/Tumor Necrosis Factor-alpha, http://linkedlifedata.com/resource/pubmed/chemical/activated protein C receptor
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0340-6245
pubmed:author
pubmed:issnType
Print
pubmed:volume
93
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
743-50
pubmed:dateRevised
2005-11-17
pubmed:meshHeading
pubmed-meshheading:15841323-Blood Coagulation Factors, pubmed-meshheading:15841323-Cells, Cultured, pubmed-meshheading:15841323-Cyclooxygenase 2, pubmed-meshheading:15841323-Endothelium, Vascular, pubmed-meshheading:15841323-Epoprostenol, pubmed-meshheading:15841323-Humans, pubmed-meshheading:15841323-Membrane Proteins, pubmed-meshheading:15841323-Prostaglandin-Endoperoxide Synthases, pubmed-meshheading:15841323-Prostaglandins, pubmed-meshheading:15841323-Protein Binding, pubmed-meshheading:15841323-Protein C, pubmed-meshheading:15841323-RNA, Messenger, pubmed-meshheading:15841323-Receptor, PAR-1, pubmed-meshheading:15841323-Receptors, Cell Surface, pubmed-meshheading:15841323-Recombinant Proteins, pubmed-meshheading:15841323-Thrombin, pubmed-meshheading:15841323-Tumor Necrosis Factor-alpha, pubmed-meshheading:15841323-Up-Regulation
pubmed:year
2005
pubmed:articleTitle
Recombinant human activated protein C upregulates cyclooxygenase-2 expression in endothelial cells via binding to endothelial cell protein C receptor and activation of protease-activated receptor-1.
pubmed:affiliation
1st Department of Medicine, Faculty of Clinical Medicine Mannheim, University of Heidelberg, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim, Germany. martina.brueckmann@med.ma.uni-heidelberg.de
pubmed:publicationType
Journal Article