Linked Life Data

21354648

Source:http://linkedlifedata.com/resource/pubmed/id/21354648

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2011-3-11
pubmed:abstractText
The epithelial Na+ channel (ENaC) plays a crucial role in electrogenic Na(+) absorption in the distal colon. ENaC induction via the mineralocorticoid receptor (MR) and the glucocorticoid receptor (GR) is differentially regulated by modulatory components. As most existing epithelial cell lines including colonic epithelial cell lines miss the co-expression of functional GR and MR, signaling on ENaC is only poorly characterized regarding the interplay of glucocorticoids and mineralocorticoids. In the present study, we show that GR expression and activity are indispensable for MR-dependent induction of ENaC-mediated Na(+) transport. Cooperativity of the two receptors has been studied in the highly differentiated, epithelial colonic cell line HT-29/B6-GR/MR which is equipped with the complete receptor repertoire of both GR and MR due to stable transfection. In contrast to HT-29/B6 cells solely expressing the MR, this cell line displays a physiological response to aldosterone regarding ENaC induction. To achieve this, a pre-incubation step with the GR agonist dexamethasone was required to allow for the subsequent stimulation of ENaC by aldosterone. As a result of cooperative effects between the activated GR and the MR, MR protein levels were elevated and MR-dependent transcription of ENaC subunits ? and ? was increased. As an additional mechanism involved, transcription of SGK-1 (serum- and glucocorticoid-induced kinase 1) and GILZ (glucocorticoid-induced leucin zipper)--both essential for the insertion of ENaC into the apical enterocyte membrane--were also augmented by the activated MR.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
1618-1298
pubmed:author
pubmed:copyrightInfo
Copyright © 2011 Elsevier GmbH. All rights reserved.
pubmed:issnType
Electronic
pubmed:volume
90
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
432-9
pubmed:meshHeading
pubmed:year
2011
pubmed:articleTitle
Glucocorticoid receptor is indispensable for physiological responses to aldosterone in epithelial Na+ channel induction via the mineralocorticoid receptor in a human colonic cell line.
pubmed:affiliation
Department of General Medicine, Charité, Campus Benjamin Franklin, Hindenburgdamm 30, 12203 Berlin, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't