Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2002-8-23
pubmed:abstractText
Inflammatory mediators such as TNF and bacterial LPS do not cause significant apoptosis of endothelial cells unless the expression of cytoprotective genes is blocked. In the case of TNF, the transcription factor NF-kappaB conveys an important survival signal. In contrast, even though LPS can also activate NF-kappaB, this signal is dispensable for LPS-inducible cytoprotective activity. LPS intracellular signals are transmitted through a member of the Toll-like receptor family, TLR4. This family of receptors transduces signals through a downstream molecule, TNFR-associated factor 6 (TRAF6). In this study, we demonstrate that the C-terminal fragment of TRAF6 (TRAF6-C) inhibits LPS-induced NF-kappaB nuclear translocation and c-Jun NH(2)-terminal kinase (JNK) activation in endothelial cells. In contrast, LPS activation of p38 kinase is not inhibited by TRAF6-C. TRAF6-C also inhibits LPS-initiated endothelial apoptosis, but potentiates TNF-induced apoptosis. LPS-induced loss of mitochondrial transmembrane potential, cytochrome c release, and caspase activation are all blocked by TRAF6-C. We demonstrate that TRAF6 signals apoptosis via JNK activation, since inhibition of JNK activation using a dominant-negative mutant also inhibits apoptosis. JNK inhibition blocks caspase activation, but the reverse is not true. Hence, JNK activation lies upstream of caspase activation in response to LPS stimulation.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0022-1767
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
169
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2611-8
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed-meshheading:12193732-Animals, pubmed-meshheading:12193732-Apoptosis, pubmed-meshheading:12193732-Cattle, pubmed-meshheading:12193732-Cell Line, pubmed-meshheading:12193732-Endothelium, Vascular, pubmed-meshheading:12193732-Enzyme Activation, pubmed-meshheading:12193732-Enzyme Inhibitors, pubmed-meshheading:12193732-Humans, pubmed-meshheading:12193732-JNK Mitogen-Activated Protein Kinases, pubmed-meshheading:12193732-Lipopolysaccharides, pubmed-meshheading:12193732-Mitogen-Activated Protein Kinases, pubmed-meshheading:12193732-NF-kappa B, pubmed-meshheading:12193732-Peptide Fragments, pubmed-meshheading:12193732-Protein Biosynthesis, pubmed-meshheading:12193732-Proteins, pubmed-meshheading:12193732-Receptors, Tumor Necrosis Factor, pubmed-meshheading:12193732-Signal Transduction, pubmed-meshheading:12193732-TNF Receptor-Associated Factor 6
pubmed:year
2002
pubmed:articleTitle
Lipopolysaccharide signals an endothelial apoptosis pathway through TNF receptor-associated factor 6-mediated activation of c-Jun NH2-terminal kinase.
pubmed:affiliation
Department of Pathology and Laboratory Medicine, British Columbia Cancer Agency, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't