Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
38
pubmed:dateCreated
1997-10-16
pubmed:abstractText
Adriamycin (or doxorubicin) is an active and broad spectrum chemotherapeutic agent. Unfortunately, its clinical use is severely restricted by a dose-limiting cardiotoxicity which has been linked to the formation of superoxide. Enzymatic one-electron reduction of adriamycin forms adriamycin semiquinone radical, which rapidly reacts with oxygen to form superoxide and adriamycin. In this way, adriamycin provides a kinetic mechanism for the one-electron reduction of oxygen by flavoenzymes such as NADPH-cytochrome P450 reductase and mitochondrial NADH dehydrogenase. We demonstrate here that the endothelial isoform of nitric oxide synthase (eNOS) reduces adriamycin to the semiquinone radical. As a consequence, superoxide formation is enhanced and nitric oxide production is decreased. Adriamycin binds to eNOS with a Km of approximately 5 microM, as calculated from both eNOS-dependent NADPH consumption and superoxide generation. Adriamycin stimulated superoxide formation is not affected by calcium/calmodulin and is abolished by the flavoenzyme inhibitor, diphenyleneiodonium. This strongly suggests that adriamycin undergoes reduction at the reductase domain of eNOS. A consequence of eNOS-mediated reductive activation of adriamycin is the disruption of the balance between nitric oxide and superoxide. This may lead eNOS to generate peroxynitrite and hydrogen peroxide, potent oxidants implicated in several vascular pathologies.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
23
pubmed:volume
36
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
11293-7
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Endothelial nitric oxide synthase-dependent superoxide generation from adriamycin.
pubmed:affiliation
Biophysics Research Institute and Department of Pathology, Caridiovascular Research Center, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't