Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2003-8-12
pubmed:abstractText
Mitochondrial production of reactive oxygen species (ROS) at Complex I of the electron transport chain is implicated in the etiology of neural cell death in acute and chronic neurodegenerative disorders. However, little is known regarding the regulation of mitochondrial ROS production by NADH-linked respiratory substrates under physiologically realistic conditions in the absence of respiratory chain inhibitors. This study used Amplex Red fluorescence measurements of H2O2 to test the hypothesis that ROS production by isolated brain mitochondria is regulated by membrane potential (DeltaPsi) and NAD(P)H redox state. DeltaPsi was monitored by following the medium concentration of the lipophilic cation tetraphenylphosphonium with a selective electrode. NAD(P)H autofluorescence was used to monitor NAD(P)H redox state. While the rate of H2O2 production was closely related to DeltaPsi and the level of NAD(P)H reduction at high values of DeltaPsi, 30% of the maximal rate of H2O2 formation was still observed in the presence of uncoupler (p-trifluoromethoxycarbonylcyanide phenylhydrazone) concentrations that provided for maximum depolarization of DeltaPsi and oxidation of NAD(P)H. Our findings indicate that ROS production by mitochondria oxidizing physiological NADH-dependent substrates is regulated by DeltaPsi and by the NAD(P)H redox state over ranges consistent with those that exist at different levels of cellular energy demand.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0022-3042
pubmed:author
pubmed:issnType
Print
pubmed:volume
86
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1101-7
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
Regulation of brain mitochondrial H2O2 production by membrane potential and NAD(P)H redox state.
pubmed:affiliation
Department of Anesthesiology, University of Maryland School of Medicine, 685 W. Baltimore Street, Baltimore, MD 21201, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.