Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
8
pubmed:dateCreated
2005-4-1
pubmed:abstractText
Endothelial cells normally form a dynamically regulated barrier at the blood-tissue interface, and breakdown of this barrier is a key pathogenic factor in inflammatory disorders such as sepsis. Pro-inflammatory signaling by the blood coagulation protease thrombin through protease activated receptor-1 (PAR1) can disrupt endothelial barrier integrity, whereas the bioactive lipid sphingosine 1-phosphate (S1P) recently has been demonstrated to have potent barrier protective effects. Activated protein C (APC) inhibits thrombin generation and has potent anti-inflammatory effects. Here, we show that APC enhanced endothelial barrier integrity in a dual-chamber system dependent on binding to endothelial protein C receptor, activation of PAR1, and activity of cellular sphingosine kinase. Small interfering RNA that targets sphingosine kinase-1 or S1P receptor-1 blocked this protective signaling by APC. Incubation of cells with PAR1 agonist peptide or low concentrations of thrombin (approximately 40 pM) had a similar barrier-enhancing effect. These results demonstrate that PAR1 activation on endothelial cells can have opposite biologic effects, reveal a role for cross-communication between the prototypical barrier-protective S1P and barrier-disruptive PAR1 pathway, and suggest that S1P receptor-1 mediates protective effects of APC in systemic inflammation.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0006-4971
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
105
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3178-84
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Endothelial barrier protection by activated protein C through PAR1-dependent sphingosine 1-phosphate receptor-1 crossactivation.
pubmed:affiliation
Department of Immunology, The Scripps Research Institute, La Jolla, CA 92037, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't