Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
2001-3-12
pubmed:abstractText
The nuclear orphan receptor CAR (constitutively active receptor or constitutive androstane receptor) can be activated in response to xenochemical exposure, such as activation by phenobarbital of a response element called NR1 found in the CYP2B gene. Here various steroids were screened for potential endogenous chemicals that may activate CAR, using the NR1 enhancer and Cyp2b10 induction in transfected HepG2 cell and/or in mouse primary hepatocytes as the experimental criteria. 17beta-Estradiol and estrone activated NR1, whereas estriol, estetrol, estradiol sulfate, and the synthetic estrogen diethylstilbestrol did not. On the other hand, progesterone and androgens repressed NR1 activity in HepG2 cells, and the repressed NR1 activity was fully restored by estradiol. Moreover, estrogen treatment elicited nuclear accumulation of CAR in the mouse livers, as well as primary hepatocytes, and induced the endogenous Cyp2b10 gene. Ovariectomy did not affect either the basal or induced level of CAR in the nucleus of the female livers, while castration slightly increased the basal and greatly increased the induced levels in the liver nucleus of male mice. Thus, endogenous estrogen appears not to regulate CAR in female mice, whereas endogenous androgen may be the repressive factor in male mice. Estrogen at pharmacological levels is an effective activator of CAR in both female and male mice, suggesting a biological and/or toxicological role of this receptor in estrogen metabolism. In addition to mouse CAR, estrogens activated rat CAR, whereas human CAR did not respond well to the estrogens under the experimental conditions.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Androgens, http://linkedlifedata.com/resource/pubmed/chemical/Aryl Hydrocarbon Hydroxylases, http://linkedlifedata.com/resource/pubmed/chemical/Cyp2b10 protein, mouse, http://linkedlifedata.com/resource/pubmed/chemical/Cytochrome P-450 Enzyme System, http://linkedlifedata.com/resource/pubmed/chemical/Estrogens, http://linkedlifedata.com/resource/pubmed/chemical/Progesterone, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Cytoplasmic and Nuclear, http://linkedlifedata.com/resource/pubmed/chemical/Steroid Hydroxylases, http://linkedlifedata.com/resource/pubmed/chemical/Steroids, http://linkedlifedata.com/resource/pubmed/chemical/Transcription Factors, http://linkedlifedata.com/resource/pubmed/chemical/constitutive androstane receptor
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0888-8809
pubmed:author
pubmed:issnType
Print
pubmed:volume
14
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1897-905
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed-meshheading:11075820-Androgens, pubmed-meshheading:11075820-Animals, pubmed-meshheading:11075820-Aryl Hydrocarbon Hydroxylases, pubmed-meshheading:11075820-Cytochrome P-450 Enzyme System, pubmed-meshheading:11075820-Enhancer Elements, Genetic, pubmed-meshheading:11075820-Estrogens, pubmed-meshheading:11075820-Female, pubmed-meshheading:11075820-Hepatocytes, pubmed-meshheading:11075820-Humans, pubmed-meshheading:11075820-Liver, pubmed-meshheading:11075820-Male, pubmed-meshheading:11075820-Mice, pubmed-meshheading:11075820-Mice, Inbred ICR, pubmed-meshheading:11075820-Ovariectomy, pubmed-meshheading:11075820-Progesterone, pubmed-meshheading:11075820-Rats, pubmed-meshheading:11075820-Receptors, Cytoplasmic and Nuclear, pubmed-meshheading:11075820-Species Specificity, pubmed-meshheading:11075820-Steroid Hydroxylases, pubmed-meshheading:11075820-Steroids, pubmed-meshheading:11075820-Transcription Factors, pubmed-meshheading:11075820-Transfection
pubmed:year
2000
pubmed:articleTitle
Estrogen activation of the nuclear orphan receptor CAR (constitutive active receptor) in induction of the mouse Cyp2b10 gene.
pubmed:affiliation
Pharmacogenetics Section, Laboratory of Reproductive and Developmental Toxicology, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina 27709, USA.
pubmed:publicationType
Journal Article