Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2004-8-31
pubmed:abstractText
Aryl hydrocarbon receptor (AhR) ligands and heavy metals are environmental co-contaminants and their molecular interaction may disrupt the coordinated regulation of AhR-dependent phase I and II drug metabolizing enzymes. To determine the effect of heavy metals on the AhR-regulated genes: cytochrome P4501A1 (Cyp1a1), NAD(P)H: quinone oxidoreductase (QOR) and glutathione S-transferase Ya (GST Ya), murine hepatoma Hepa 1c1c7 cells were treated with increasing concentrations of As3+ (1-10 microM), Cd2+ (1-25 microM) and Cr6+ (1-25 microM) with or without the AhR ligands: 2,3,7,8-tetrachlorodibenzo-p-dioxin (0.1 nM), 3-methylcholanthrene (0.25 microM), beta-naphthoflavone (10 uM), or benzo[a]pyrene (1 microM). Our results show that AhR ligands alone and As3+ or Cd2+ alone increased the catalytic activities and mRNA levels of all AhR-regulated genes. When metals were co-administered with an AhR ligand, all three metals inhibited the induction of Cyp1a1 activity by the AhR ligands but potentiated its mRNA and protein expression. In addition, all metals enhanced QOR and GST Ya at the activity and mRNA levels but modulated their induction by AhR ligands in a concentration, metal, and AhR ligand-dependent manner. Generally, Cr6+ inhibited while As3+ and Cd2+ potentiated the induction of QOR and GST Ya activities and mRNA levels. The three metals enhanced the expression of heme oxygenase-1, which coincided with the changes in the phase I and phase II enzyme activities. These results show that the ability of metals to alter the capacity of AhR ligands to induce the bioactivating phase I and the detoxifying phase II enzymes will influence the carcinogenicity and mutagenicity of the AhR ligands.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Arsenic, http://linkedlifedata.com/resource/pubmed/chemical/Cadmium, http://linkedlifedata.com/resource/pubmed/chemical/Carcinogens, http://linkedlifedata.com/resource/pubmed/chemical/Chromium, http://linkedlifedata.com/resource/pubmed/chemical/Cytochrome P-450 Enzyme System, http://linkedlifedata.com/resource/pubmed/chemical/Drug Combinations, http://linkedlifedata.com/resource/pubmed/chemical/Heme Oxygenase (Decyclizing), http://linkedlifedata.com/resource/pubmed/chemical/Heme Oxygenase-1, http://linkedlifedata.com/resource/pubmed/chemical/Ligands, http://linkedlifedata.com/resource/pubmed/chemical/Mutagens, http://linkedlifedata.com/resource/pubmed/chemical/RNA, Messenger, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Aryl Hydrocarbon
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0300-483X
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
202
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
249-69
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:15337587-Animals, pubmed-meshheading:15337587-Arsenic, pubmed-meshheading:15337587-Cadmium, pubmed-meshheading:15337587-Carcinogens, pubmed-meshheading:15337587-Carcinoma, Hepatocellular, pubmed-meshheading:15337587-Chromium, pubmed-meshheading:15337587-Cytochrome P-450 Enzyme System, pubmed-meshheading:15337587-Dose-Response Relationship, Drug, pubmed-meshheading:15337587-Drug Combinations, pubmed-meshheading:15337587-Gene Expression Regulation, Neoplastic, pubmed-meshheading:15337587-Heme Oxygenase (Decyclizing), pubmed-meshheading:15337587-Heme Oxygenase-1, pubmed-meshheading:15337587-Ligands, pubmed-meshheading:15337587-Mutagens, pubmed-meshheading:15337587-RNA, Messenger, pubmed-meshheading:15337587-Receptors, Aryl Hydrocarbon, pubmed-meshheading:15337587-Tumor Cells, Cultured
pubmed:year
2004
pubmed:articleTitle
Modulation of aryl hydrocarbon receptor-regulated gene expression by arsenite, cadmium, and chromium.
pubmed:affiliation
Faculty of Pharmacy and Pharmaceutical Sciences, 3118 Dentistry/Pharmacy Centre, University of Alberta, Edmonton, Alta., T6G 2N8, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't