Linked Life Data

9619450

Source:http://linkedlifedata.com/resource/pubmed/id/9619450

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
1998-6-25
pubmed:abstractText
The mRNA expressions of UCP2 and UCP3, two newly described genes with high sequence homology to the uncoupling protein UCP1 in brown adipose tissue (BAT), were examined in two skeletal muscles (gastrocnemius and soleus) as well as in interscapular BAT (IBAT) of the rat in response to food deprivation and controlled refeeding. In IBAT (a tissue highly dependent on lipids for thermogenesis), the pattern of mRNA expression of UCP2 and UCP3 closely follows that of UCP1: it was markedly down-regulated during food deprivation (when this tissue's thermogenesis and lipid fuel requirements are decreased) and restored to control levels by day 5 of refeeding. By contrast, in the gastrocnemius muscle (a mixed fiber type muscle with a high capacity to shift between glucose and lipids as fuel substrate), mRNA expression of both UCP2 and UCP3 mRNA was found to be markedly up-regulated during food deprivation (when this tissue's thermogenesis is also decreased but its lipid fuel utilization is increased). The expressions were subsequently found to be markedly down-regulated upon transition to refeeding, with mRNA levels remaining below control levels on days 3, 5, and 10 of refeeding (period of enhanced efficiency of body fat deposition). In the soleus muscle (an oxidative type muscle with higher dependency on lipids than the gastrocnemius, and hence with a lower capacity to shift between lipids and glucose as fuel substrate), UCP homologues were also found to be up-regulated during food deprivation, but changes in their mRNA expression contrast with those in the gastrocnemius muscle both in their much lower magnitude of response to food deprivation and in their more rapid restoration to control levels during refeeding. Up-regulation of UCP2 and UCP3 gene expressions in skeletal muscle during food deprivation was found to persist at thermoneutrality (i.e., under conditions of reduced thermoregulatory thermogenesis). Together, these tissue-dependent differential mRNA expressions of the UCP homologues in IBAT, gastrocnemius, and soleus muscles during food deprivation and refeeding are much more consistent with a role for UCP2 and UCP3 in the regulation of lipids as fuel substrate rather than as mediators of regulatory thermogenesis.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0892-6638
pubmed:author
pubmed:issnType
Print
pubmed:volume
12
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
715-24
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:9619450-Adipose Tissue, Brown, pubmed-meshheading:9619450-Animals, pubmed-meshheading:9619450-Body Composition, pubmed-meshheading:9619450-Body Temperature Regulation, pubmed-meshheading:9619450-Carrier Proteins, pubmed-meshheading:9619450-Energy Metabolism, pubmed-meshheading:9619450-Food Deprivation, pubmed-meshheading:9619450-Gene Expression Regulation, pubmed-meshheading:9619450-Ion Channels, pubmed-meshheading:9619450-Lipid Metabolism, pubmed-meshheading:9619450-Male, pubmed-meshheading:9619450-Membrane Transport Proteins, pubmed-meshheading:9619450-Mitochondrial Proteins, pubmed-meshheading:9619450-Muscle, Skeletal, pubmed-meshheading:9619450-Proteins, pubmed-meshheading:9619450-RNA, Messenger, pubmed-meshheading:9619450-Rats, pubmed-meshheading:9619450-Rats, Sprague-Dawley, pubmed-meshheading:9619450-Sequence Homology, Amino Acid, pubmed-meshheading:9619450-Uncoupling Agents
pubmed:year
1998
pubmed:articleTitle
Role of UCP homologues in skeletal muscles and brown adipose tissue: mediators of thermogenesis or regulators of lipids as fuel substrate?
pubmed:affiliation
Department of Physiology, Faculty of Medicine, University of Geneva, Switzerland.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't