Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1991-7-24
pubmed:abstractText
A systematic study of the effects of the synthetic glucocorticoid, methylprednisolone (MP), on respiration and energy coupling in tightly-coupled mitochondria isolated from rat tissues has been initiated. In intact rat skeletal muscle, liver and heart mitochondria, incubation, in vitro, with greater than or equal to 0.1 mM MP caused inhibition of the state 3 respiratory rates with succinate and NAD-linked substrates. In skeletal muscle and heart mitochondria, the oxidation of succinate was significantly more sensitive to MP than was that of the NAD-linked substrates. No effects were seen at low concentrations (less than 0.02 mM) of MP. In all three tissues, these data together with analysis of the partial reactions of the electron transport chain and steady-state kinetic analysis of cytochrome reduction indicated that in isolated mitochondria high concentrations of MP: (a) inhibit the oxidation of NAD-linked substrates at the level of the respiratory chain between the primary NADH dehydrogenase flavoprotein and coenzyme Q, most likely at the iron-sulfur centers or coenzyme Q-binding proteins of complex I; and (b) inhibit succinate oxidation in intact (but not disrupted) mitochondria, not by inhibiting electron transfer along the respiratory chain, but possibly at the level of succinate transport into the mitochondria. The results of these studies suggest that the therapeutic effects of MP in mitochondrial disease result from indirect effects rather than direct effects on the mitochondrial membrane. More importantly, the absence of an effect at low MP concentrations provides the baseline information needed for further studies to be carried out in vivo.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0006-3002
pubmed:author
pubmed:issnType
Print
pubmed:day
17
pubmed:volume
1058
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
152-60
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1991
pubmed:articleTitle
In vitro effects of glucocorticoid on mitochondrial energy metabolism.
pubmed:affiliation
Department of Neurology, Wayne State University School of Medicine, Detroit, MI.
pubmed:publicationType
Journal Article, In Vitro, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't