Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2010-4-22
pubmed:abstractText
Glucocorticoids increase pyruvate dehydrogenase kinase-4 (PDK4) mRNA and protein expression, which phosphorylates pyruvate dehydrogenase, thereby preventing the formed pyruvate from undergoing mitochondrial oxidation. This increase in PDK4 expression is mediated by the mandatory presence of Forkhead box other factors (FoxOs) in the nucleus. In the current study, we examined the importance of the nongenomic effects of dexamethasone (Dx) in determining the compartmentalization of FoxO and hence its transcriptional activity. Rat cardiomyocytes exposed to Dx produced a robust decrease in glucose oxidation. Measurement of FoxO compartmentalization demonstrated increase in nuclear but resultant decrease in cytosolic content of FoxO1 with no change in the total content. The increase in nuclear content of FoxO1 correlated to an increase in nuclear phospho-p38 MAPK together with a robust association between this transcription factor and kinase. Dx also promoted nuclear retention of FoxO1 through a decrease in phosphorylation of Akt, an effect mediated by heat shock proteins binding to Akt. Measurement of the nuclear and total expression of sirtuin-1 protein showed no change after Dx. Instead, Dx increased the association of sirtuin-1 with FoxO1, thereby causing a decrease in FoxO acetylation. Manipulation of FoxO1 through agents that interfere with its nuclear shuttling or acetylation were effective in reducing Dx-induced increase in PDK4 protein expression. Our data suggest that FoxO1 has a major PDK4-regulating function. In addition, given the recent suggestions that altering glucose use can set the stage for heart failure, manipulating FoxO could assist in devising new therapeutic strategies to optimize cardiac metabolism and prevent PDK4 induced cardiac complications.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Dexamethasone, http://linkedlifedata.com/resource/pubmed/chemical/Forkhead Transcription Factors, http://linkedlifedata.com/resource/pubmed/chemical/Foxo1 protein, rat, http://linkedlifedata.com/resource/pubmed/chemical/Glucocorticoids, http://linkedlifedata.com/resource/pubmed/chemical/Glucose, http://linkedlifedata.com/resource/pubmed/chemical/Hypoglycemic Agents, http://linkedlifedata.com/resource/pubmed/chemical/Insulin, http://linkedlifedata.com/resource/pubmed/chemical/Nerve Tissue Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Protein Kinases, http://linkedlifedata.com/resource/pubmed/chemical/Proto-Oncogene Proteins c-akt, http://linkedlifedata.com/resource/pubmed/chemical/p38 Mitogen-Activated Protein..., http://linkedlifedata.com/resource/pubmed/chemical/pyruvate dehydrogenase kinase 4
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
1945-7170
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
151
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2306-18
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed-meshheading:20181797-Active Transport, Cell Nucleus, pubmed-meshheading:20181797-Animals, pubmed-meshheading:20181797-Blotting, Western, pubmed-meshheading:20181797-Cell Nucleus, pubmed-meshheading:20181797-Cells, Cultured, pubmed-meshheading:20181797-Dexamethasone, pubmed-meshheading:20181797-Dose-Response Relationship, Drug, pubmed-meshheading:20181797-Forkhead Transcription Factors, pubmed-meshheading:20181797-Gene Expression Regulation, Enzymologic, pubmed-meshheading:20181797-Glucocorticoids, pubmed-meshheading:20181797-Glucose, pubmed-meshheading:20181797-Hypoglycemic Agents, pubmed-meshheading:20181797-Insulin, pubmed-meshheading:20181797-Myocytes, Cardiac, pubmed-meshheading:20181797-Nerve Tissue Proteins, pubmed-meshheading:20181797-Oxidation-Reduction, pubmed-meshheading:20181797-Phosphorylation, pubmed-meshheading:20181797-Protein Kinases, pubmed-meshheading:20181797-Proto-Oncogene Proteins c-akt, pubmed-meshheading:20181797-Rats, pubmed-meshheading:20181797-Reverse Transcriptase Polymerase Chain Reaction, pubmed-meshheading:20181797-Signal Transduction, pubmed-meshheading:20181797-Time Factors, pubmed-meshheading:20181797-p38 Mitogen-Activated Protein Kinases
pubmed:year
2010
pubmed:articleTitle
The increase in cardiac pyruvate dehydrogenase kinase-4 after short-term dexamethasone is controlled by an Akt-p38-forkhead box other factor-1 signaling axis.
pubmed:affiliation
Division of Pharmacology and Toxicology, Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, British Columbia, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't