Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2003-12-3
pubmed:abstractText
Stress hormones and pro-inflammatory cytokines are putative signals triggering increased energy expenditure or "hypermetabolism" commonly observed in inflammatory states. Cytokines also cause the release of reactive oxidants by immune cells resident in tissues in vivo. Therefore, we hypothesized that oxidative stress plays a role in the induction of hypermetabolism. We examined the effect of glucagon (1.0 nM), a catabolic stress hormone, and the oxidant H(2)O(2) (1.0 mM) on the metabolism of stable hepatocyte cultures for 4 days. Combined H(2)O(2) and glucagon treatment, but not H(2)O(2) or glucagon used alone, increased the hepatocyte oxygen uptake rate 25% above control untreated cells after a lag-time of 72 h. The same treatment also increased the expression of mitochondrial uncoupling protein-2 (UCP2). These effects were significantly inhibited by the antioxidant N-acetylcysteine (5mM) and the pentose phosphate pathway (PPP) inhibitor dehydroepianderosterone (200 microM). Glucagon alone induced urea synthesis and H(2)O(2) alone induced the PPP. These findings show, for the first time, that oxidative stress, in combination with glucagon, increases metabolic energy expenditure in cultured cells, and that this effect may be mediated by UCP-2. Furthermore, the results implicate the PPP in the induction of the hypermetabolic response.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
1096-7176
pubmed:author
pubmed:issnType
Print
pubmed:volume
5
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
221-9
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:14642350-Animals, pubmed-meshheading:14642350-Basal Metabolism, pubmed-meshheading:14642350-Cell Survival, pubmed-meshheading:14642350-Cells, Cultured, pubmed-meshheading:14642350-Dose-Response Relationship, Drug, pubmed-meshheading:14642350-Drug Combinations, pubmed-meshheading:14642350-Energy Metabolism, pubmed-meshheading:14642350-Female, pubmed-meshheading:14642350-Glucagon, pubmed-meshheading:14642350-Hepatocytes, pubmed-meshheading:14642350-Hydrogen Peroxide, pubmed-meshheading:14642350-Ion Channels, pubmed-meshheading:14642350-Membrane Transport Proteins, pubmed-meshheading:14642350-Mitochondrial Proteins, pubmed-meshheading:14642350-Oxidation-Reduction, pubmed-meshheading:14642350-Oxidative Stress, pubmed-meshheading:14642350-Oxygen Consumption, pubmed-meshheading:14642350-Pentose Phosphate Pathway, pubmed-meshheading:14642350-Rats, pubmed-meshheading:14642350-Rats, Inbred Lew
pubmed:year
2003
pubmed:articleTitle
Induction of a hypermetabolic state in cultured hepatocytes by glucagon and H2O2.
pubmed:affiliation
Center for Engineering in Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't