title: In vitro assessment of potential mechanism-specific effects of polybrominated diphenyl ethers.
abstract: This study examined the ability of environmentally relevant concentrations of 10 different polybrominated diphenyl ethers (PBDEs) to induce aryl hydrocarbon receptor (AhR)- and estrogen receptor (ER)-mediated gene expression in vitro. It also examined the ability of PBDEs to displace steroid hormones from serum proteins in vitro. At concentrations ranging up to 880 ng/ ml, none of the PBDEs significantly displaced tritiated 17beta-estradiol (E2) or testosterone from hormone-stripped carp serum. At concentrations ranging up to 500 ng/ml, 9 of 10 PBDEs tested failed to induce ER- or AhR-mediated gene expression in MVLN and H4IIE-luc cells, respectively. One congener, 3,3',4,4',5-pentabromodiphenylether (BDE 126), induced significant AhR-mediated gene expression at 500 ng/ml, but the magnitude of induction was only 13% of that caused by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Overall, the PBDEs tested were found to be at least 200,000 times less potent than TCDD and 50,000 times less potent than E2 for inducing AhR- and ER-mediated gene expression, respectively.
authors.affiliation: National Food Safety and Toxicology Center, Department of Zoology and Institute for Environmental Toxicology, Michigan State University, East Lansing 48824-1311, USA. villene1@msu.edu
authors.forename: Daniel L
authors.initials: DL
authors.lastname: Villeneuve
authors.forename: Kurunthachalam
authors.initials: K
authors.lastname: Kannan
authors.forename: Benjamin T
authors.initials: BT
authors.lastname: Priest
authors.forename: John P
authors.initials: JP
authors.lastname: Giesy
mesh_terms: D000818:Animals; D001681:Biological Assay; D001798:Blood Proteins / Q000378:metabolism; D002347:Carps; D004785:Environmental Pollutants / Q000633:toxicity*; D004958:Estradiol / Q000378:metabolism*; D005260:Female; D005411:Flame Retardants / Q000633:toxicity*; D015870:Gene Expression; D006801:Humans; D010647:Phenyl Ethers; D011075:Polybrominated Biphenyls / Q000633:toxicity*; D051381:Rats; D018336:Receptors, Aryl Hydrocarbon / Q000096:biosynthesis* / Q000235:genetics; D011960:Receptors, Estrogen / Q000096:biosynthesis* / Q000235:genetics; D013329:Structure-Activity Relationship; D013739:Testosterone / Q000378:metabolism*; D014407:Tumor Cells, Cultured
chemical_list: D001798:Blood Proteins; D004785:Environmental Pollutants; D005411:Flame Retardants; D010647:Phenyl Ethers; D011075:Polybrominated Biphenyls; D018336:Receptors, Aryl Hydrocarbon; D011960:Receptors, Estrogen; D013739:Testosterone; D004958:Estradiol