Linked Life Data

10385701

Source:http://linkedlifedata.com/resource/pubmed/id/10385701

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1999-7-22
pubmed:abstractText
Mammalian lipoxygenases have been implicated in inflammation and atherosclerosis and, thus, lipoxygenase inhibitors may be of pharmacological interest. In cells, lipoxygenases occur in a catalytically silent ground state that requires activation to become active. We found that the seleno-organic drug ebselen [2-phenyl-1, 2-benzisoselenazol-3(2H)-one], which exhibits anti-inflammatory properties, irreversibly inhibited pure rabbit 15-lipoxygenase, with an IC50 in the nM range when preincubated with the enzyme in the absence of fatty acid substrates. Subsequent dialysis, gel filtration, or substrate addition did not restore the enzyme activity, and experiments with [14C]ebselen indicated a covalent linkage of the drug. The presence of sulfhydryl compounds in the incubation mixture prevented both enzyme labeling and inactivation, but we did not see any reactivation when sulfhydryl compounds were added afterward. X-ray absorption studies indicated that ebselen did alter the geometry of the iron ligand sphere, and the data are consistent with an iron complexation by the drug. When fatty acid substrate was present during lipoxygenase-ebselen interaction, the inhibitory potency was strongly reduced and a competitive mode of action was observed. These data suggest that ebselen inactivated the catalytically silent ground-state lipoxygenase irreversibly by covalent linkage and alteration of the iron ligand sphere. In contrast, it functions as a competitive inhibitor of the catalytically active enzyme species. The pharmacological relevance of ebselen as a potential in vivo lipoxygenase inhibitor will be discussed.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0026-895X
pubmed:author
pubmed:issnType
Print
pubmed:volume
56
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
196-203
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
The inhibition of mammalian 15-lipoxygenases by the anti-inflammatory drug ebselen: dual-type mechanism involving covalent linkage and alteration of the iron ligand sphere.
pubmed:affiliation
Institute of Biochemistry, University Clinics Charité, Humboldt University, Berlin, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't