Linked Life Data

9823018

Source:http://linkedlifedata.com/resource/pubmed/id/9823018

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-2
pubmed:dateCreated
1999-2-5
pubmed:abstractText
Regulation of intracellular Ca2+ ([Ca2+]i) plays a key role in obesity, insulin resistance and hypertension, and [Ca2+]i disorders may represent a fundamental factor linking these three conditions. We have shown insulin to be a direct vasodilator, attenuating voltage-gated Ca2+ influx and stimulating Ca(2+)-ATPase transcription via a glucose-6-phosphate response element. These result in a net decrease in [Ca2+]i and thereby decrease vascular resistance, while these effects are blunted in insulin resistance, leading to increased vascular resistance. Consistent with this concept, pharmacological amplification of peripheral insulin sensitivity results in reduced arterial pressure. While insulin regulates [Ca2+]i, Ca2+ also regulates insulin signaling, as increasing [Ca2+]i impairs insulin signaling in some systems, possibly due to Ca2+ inhibition of insulin-regulated dephosphorylation. Finally, in recent studies of the mouse agouti gene, we have also demonstrated increased [Ca2+]i to play a key role in adipocyte lipogenesis, as follows. We have found dominant agouti mutants to exhibit increased [Ca2+]i in most tissues, leading to increased vascular reactivity and insulin resistance in vascular smooth muscle and skeletal muscle cells, respectively. Further, we have found recombinant agouti protein to directly increase [Ca2+]i in a variety of cells, including murine and human adipocytes, and to stimulate both the expression and activity of adipocyte fatty acid synthase and increase triglyceride accumulation in a Ca(2+)-dependent manner. These effects can be mimicked by stimulation of Ca2+ influx and blocked by Ca2+ channel inhibition, while treatment of mice with a Ca2+ antagonist attenuates agouti-induced obesity. Since humans express agouti in adipose tissue, it may similarly exert paracrine effects on [Ca2+]i and thereby stimulate de novo lipogenesis and promote obesity. Thus, Ca2+ signaling represents a target for therapeutic intervention in obesity as well as hypertension and insulin resistance.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0300-8177
pubmed:author
pubmed:issnType
Print
pubmed:volume
188
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
129-36
pubmed:dateRevised
2005-11-16
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Nutritional and endocrine modulation of intracellular calcium: implications in obesity, insulin resistance and hypertension.
pubmed:affiliation
Department of Nutrition, University of Tennessee, Knoxville 37996-1900, USA.
pubmed:publicationType
Journal Article, Review