Linked Life Data

16230783

Source:http://linkedlifedata.com/resource/pubmed/id/16230783

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2005-10-18
pubmed:abstractText
Theca-interstitial (T-I) cells synthesize androgens that are converted to estrogen by the granulosa cells. In rat ovary, T-I cells primarily utilize HDL-derived cholesteryl esters (CE) as a precursor for androgen synthesis. The HDL-CE is delivered to steroidogenic cells by a process termed "selective" uptake in which CE is internalized without the simultaneous uptake of apolipoprotein(s). This process is mediated by an HDL receptor, scavenger receptor class B, type I (SR-BI) and is stimulated by trophic hormone (LH/hCG), which also activates the cAMP cascade. In this study, we tested whether the adenoviral (Ad)-mediated introduction of a dominant-negative analog of cyclic AMP response element binding protein (A-CREB) inhibits the stimulatory effect of LH/hCG on the selective uptake of high-density lipoprotein (HDL)-cholesterol and androgen production in primary cultures of rat T-I cells. Androstenedione production by cultured T-I cells was stimulated by hCG and by the adenoviral overexpression of wtCREB. Additionally, the stimulatory effect observed with hCG was amplified in the presence of HDL. Androgen synthesis was increased 17-fold in the presence of HDL and hCG but the stimulatory effect of hCG was inhibited by Ad A-CREB by approx 70%. In the selective up-take studies, cell-surface association of the labeled HDL was significantly enhanced by hCG treatment, and this effect was inhibited by Ad A-CREB. The selective uptake of HDL-cholesterol was also enhanced by hCG but exposure to Ad A-CREB also abrogated this effect. It is concluded that CREB plays an intermediary role in the stimulatory action of LH/hCG on androgen synthesis and the selective uptake of HDL-cholesterol in T-I cells.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
1355-008X
pubmed:author
pubmed:issnType
Print
pubmed:volume
27
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
269-77
pubmed:dateRevised
2010-6-24
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
LH/hCG-stimulated androgen production and selective HDL-cholesterol transport are inhibited by a dominant-negative CREB construct in primary cultures of rat theca-interstitial cells.
pubmed:affiliation
Department of Obstetrics and Gynecology, University of Michigan Medical School, Ann Arbor, MI 48109, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S., Research Support, N.I.H., Extramural