Linked Life Data

12957657

Source:http://linkedlifedata.com/resource/pubmed/id/12957657

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2003-9-5
pubmed:abstractText
Inhibition of Fas-mediated apoptosis in B cell lymphomas by thiol antioxidants (glutathione and N-acetylcysteine) supported previous studies, suggesting that Fas-stimulated ROS generation may play a role in Fas-mediated apoptosis. Thus, the goal of the current study was to determine if Fas stimulation could induce ROS generation and what role, if any, it played in apoptosis. Fas crosslinking induced rapid generation of ROS (within 15 min) well before the appearance of characteristic apoptotic changes. Overexpression of catalase or superoxide dismutase suggested that Fas induced production of both superoxide anion and hydrogen peroxide. ROS generation was only observed, however, in cells that were sensitive to apoptosis and not in B cells inherently resistant to anti-Fas or in those in which resistance was induced by B cell receptor crosslinking. The exogenous addition of 250 microM hydrogen peroxide could reverse the resistant phenotype and sensitize cells to Fas-induced apoptosis. In Fas-sensitive cells, depletion of endogenous antioxidant defenses with buthionine sulfoximine increased the sensitivity to Fas-induced apoptosis, while overexpression of antioxidant enzymes and antiapoptotic proteins suggested a role for Fas-induced production of hydrogen peroxide in apoptosis. Further analysis suggested a redox-sensitive step early in Fas signaling at the level of initiator caspase (caspase-8) activation. Thus, the data suggest that the level of oxidative stress, either from exogenous sources or generated endogenously upon receptor stimulation, regulates the sensitivity to Fas-mediated apoptosis.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0891-5849
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
35
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
648-61
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
Fas-stimulated generation of reactive oxygen species or exogenous oxidative stress sensitize cells to Fas-mediated apoptosis.
pubmed:affiliation
Immunology Department, American Red Cross Biomedical Research and Development, Rockville, MD 20855, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't