Linked Life Data

10049734

Source:http://linkedlifedata.com/resource/pubmed/id/10049734

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1999-3-11
pubmed:abstractText
Recent studies have suggested that hydrogen peroxide (H2O2), a reactive compound formed endogenously in the breakdown of superoxide, may mediate the induction of apoptosis in various cell types in response to external stimuli. However, the role of H2O2 in the apoptotic pathway has not been clearly established. The purpose of this study was to determine if H2O2 treatment could induce apoptosis through the activation of caspases. Doses of H2O2 ranging from 10 microM to 100 microM, when added to HL-60 cells, resulted in the cleavage of poly(ADP-ribose) polymerase (PARP) from its native 113 Kd form to a processed 89 Kd fragment, indicative of cells undergoing apoptosis. PARP was predominantly in the fragmented form when doses of 20 microM and greater were used. A time course study of changes in PARP processing in H2O2-treated cells revealed that 10 and 50 microM H2O2 required 6 and 3 h, respectively, to specifically degrade PARP, suggesting that the H2O2-induced PARP cleavage is both time and concentration dependent. Since PARP is cleaved by CPP32 (caspase-3), we next determined if H2O2 was capable of effecting changes in CPP32 activity. The caspase activity was assayed using a colorimetric substrate, DEVD-pNa. Results of these experiments showed that H2O2 increased caspase activity at 3 h, corresponding to the time of appearance of fragmented PARP. Also, CPP32 activity and PARP processing were both significantly suppressed by caspase-3 inhibitors. Taken together, these results suggest that H2O2 mediates specific cleavage of PARP and possibly apoptosis by activating caspase 3.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0006-291X
pubmed:author
pubmed:copyrightInfo
Copyright 1999 Academic Press.
pubmed:issnType
Print
pubmed:day
16
pubmed:volume
255
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
477-82
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
Activation of caspase 3 in HL-60 cells exposed to hydrogen peroxide.
pubmed:affiliation
Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla 10595, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't