Linked Life Data

21683692

Source:http://linkedlifedata.com/resource/pubmed/id/21683692

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2011-8-8
pubmed:abstractText
Ellipticine is a pro-drug, whose activation is dependent on its oxidation by cytochromes P450 (CYP) and peroxidases. Cytochrome b(5) alters the ratio of ellipticine metabolites formed by isolated reconstituted CYP1A1 and 1A2, favoring formation of 12-hydroxy- and 13-hydroxyellipticine metabolites implicated in ellipticine-DNA adduct formation, at the expense of 9-hydroxy- and 7-hydroxyellipticine that are detoxication products. Cytochrome b(5) enhances the production of 12-hydroxy and 13-hydroxyellipticine. The change in metabolite ratio results in an increased formation of covalent ellipticine-DNA adducts, one of the DNA-damaging mechanisms of ellipticine antitumor action. This finding explains previous apparent discrepancies found with isolated enzymes and in vivo, where CYP1A enzymatic activation correlated with ellipticine-DNA-adduct levels while isolated CYP1A1 or 1A2 in reconstituted systems were much less effective than CYP3A4. The effect of cytochrome b(5) might be even more pronounced in vivo, since, as we show here, ellipticine increases levels of cytochrome b(5) in rat liver. Our results demonstrate that both the native 3D structure of cytochrome b(5) and the presence of the heme as an electron transfer agent in this protein enable a shift in ellipticine metabolites formed by CYP1A1/2.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
1873-2968
pubmed:author
pubmed:copyrightInfo
Copyright © 2011 Elsevier Inc. All rights reserved.
pubmed:issnType
Electronic
pubmed:day
15
pubmed:volume
82
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
669-80
pubmed:meshHeading
pubmed:year
2011
pubmed:articleTitle
Cytochrome b(5) shifts oxidation of the anticancer drug ellipticine by cytochromes P450 1A1 and 1A2 from its detoxication to activation, thereby modulating its pharmacological efficacy.
pubmed:affiliation
Department of Biochemistry, Faculty of Science, Charles University, Albertov 2030, 128 40 Prague 2, Czech Republic.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't