Linked Life Data

16135775

Source:http://linkedlifedata.com/resource/pubmed/id/16135775

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
10
pubmed:dateCreated
2005-9-26
pubmed:abstractText
Hypoxia evokes a common mechanism of oxygen sensing mediated by hypoxia-inducible transcription factors (HIF) in many mammalian cells. This study investigated the effect of hypoxia on group-IIA secretory phospholipase A(2) (sPLA(2)-IIA) expression in renal mesangial cells. Stimulation of cells with IL-1beta under normoxic conditions (21% O(2)) is known to induce expression and secretion of the group sPLA(2)-IIA. This induction is further enhanced by constantly reducing the O(2) concentration to 1% O(2), and is accompanied by increased sPLA(2) activity. To see whether hypoxia potentiates IL-1beta-induced sPLA(2)-IIA gene expression, a 2.67-kb fragment of the rat sPLA(2)-IIA promoter was fused to a luciferase reporter construct and used to transfect mesangial cells. Hypoxia alone is not able to activate the sPLA(2) promoter, whereas it significantly enhances IL-1beta-stimulated promoter activity. A deletion mutant of the promoter that lacks the two putative hypoxia responsive elements (HRE) is devoid of the potentiating effect of hypoxia. Moreover, site-directed mutagenesis of either of the two HRE is sufficient to abolish the potentiating effect of hypoxia. Electrophoretic mobility shift assays show that HIF-2alpha, which is the only HIF subtype expressed in mesangial cells, binds to both HRE in the sPLA(2)-IIA promoter. In summary, the data show that in an inflammatory setting hypoxia is able to potentiate sPLA(2)-IIA expression and activity in renal mesangial cells, and thereby may critically contribute to enhanced formation of inflammatory lipid mediators seen in a diverse range of kidney diseases.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
1046-6673
pubmed:author
pubmed:issnType
Print
pubmed:volume
16
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2897-905
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Hypoxia increases group IIA phospholipase A(2) expression under inflammatory conditions in rat renal mesangial cells.
pubmed:affiliation
Pharmazentrum Frankfurt, Klinikum der Johann Wolfgang Goethe-Universität, Theodor-Stern-Kai 7, D-60590 Frankfurt am Main, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't