Linked Life Data

9266502

Source:http://linkedlifedata.com/resource/pubmed/id/9266502

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:dateCreated
1997-11-14
pubmed:abstractText
The experiments reported here were undertaken to test the hypothesis that the antioxidative, reduced form of hydrophobic phase coenzyme Q (CoQ) may be generated and maintained by the two-electron quinone reductase, DT-diaphorase [NAD(P)H:(quinone-acceptor) oxidoreductase, EC 1.6.99.2] by catalyzing formation of the hydroquinone form of CoQ. This enzyme was isolated and purified from rat liver cytosol and its reduction of several CoQ homologs incorporated into large unilamellar vesicles (LUVETs) was demonstrated. The addition of NADH and DT-diaphorase to LUVETs and to multilamellar vesicles (MLVs) containing CoQ homologs, including CoQ9 and CoQ10, resulted in essentially complete reduction of the CoQ. Incorporation of either CoQ9H2 or CoQ10H2 and the lipophylic radical generator 2,2'-azobis(2,4-dimethylvaleronitrile) (AMVN) into MLVs in the presence of DT-diaphorase and NADH maintained the reduced state of CoQ and inhibited lipid peroxidation. The reaction between DT-diaphorase and CoQ was also demonstrated in isolated rat liver hepatocytes in which incorporation of CoQ10 provided protection from adriamycin (adr)-induced mitochondrial membrane damage. The role of DT-diaphorase in the antioxidant activity of CoQ was demonstrated by the co-incorporation of dicoumarol (dic), a potent inhibitor of DT-diaphorase, resulting in a loss of protection by incorporated CoQ10. These results support the antioxidant function of DT-diaphorase in both artificial and natural membrane systems by acting as a two-electron CoQ reductase which forms and maintains CoQ in the reduced state.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0098-2997
pubmed:author
pubmed:issnType
Print
pubmed:volume
18 Suppl
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
S15-23
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
The two-electron quinone reductase DT-diaphorase generates and maintains the antioxidant (reduced) form of coenzyme Q in membranes.
pubmed:affiliation
Department of Biology, University of Michigan, Ann Arbor 48105-1737, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't