title: Evaluation of chemicals with endocrine modulating activity in a yeast-based steroid hormone receptor gene transcription assay.
abstract: There is a concern that chemicals in our environment are affecting human health by disrupting normal endocrine function. Much of the concern has focused on chemicals that can interact directly with steroid hormone receptors. We have used a yeast-based assay to assess chemical interactions with the estrogen, androgen, and progesterone receptors. The yeast transformants used in this study contained the human estrogen, androgen, or progesterone receptor along with the appropriate steroid responsive elements upstream of the beta-galactosidase reporter gene. Chemicals were added to yeast cultures in doses ranging from 10(-12) to 10(-4) M and following incubation, the yeasts were then lysed and assayed for beta-galactosidase activity. Diethylstilbesterol and 17-beta estradiol were most active in the estrogen receptor assay, followed by the phytoestrogen, coumestrol. p-Nonylphenol and bisphenol A were approximately 5000- and 15,000-fold less active, respectively, than estradiol. Methoxychlor, DDT and its metabolites, o,p'-DDD, and o,p'-DDE ranged in potency from 5 to 24 X 10(6) less potent than estradiol. Testosterone and dihydrotestosterone were most potent in the androgen receptor assay, followed by estradiol and progesterone. p,p'-DDE was approximately 10(6)-fold less potent than testosterone. None of the industrial chemicals tested interacted with the progesterone receptor. These data demonstrate the utility of using yeast-based receptor assays for detecting chemical interaction with steroid receptors and these assays should serve as a useful component of an in vitro-in vivo strategy to assess the effects of chemicals on endocrine function.
authors.affiliation: Chemical Industry Institute of Toxicology, Research Triangle Park, North Carolina 27709, USA. gaido@ciit.org
authors.forename: K W
authors.initials: KW
authors.lastname: Gaido
authors.forename: L S
authors.initials: LS
authors.lastname: Leonard
authors.forename: S
authors.initials: S
authors.lastname: Lovell
authors.forename: J C
authors.initials: JC
authors.lastname: Gould
authors.forename: D
authors.initials: D
authors.lastname: Babaï
authors.forename: C J
authors.initials: CJ
authors.lastname: Portier
authors.forename: D P
authors.initials: DP
authors.lastname: McDonnell
mesh_terms: D003634:DDT / Q000633:toxicity; D004305:Dose-Response Relationship, Drug; D004702:Endocrine Glands / Q000503:physiopathology*; D004785:Environmental Pollutants / Q000633:toxicity*; D005485:Flutamide / Q000031:analogs & derivatives / Q000494:pharmacology; D006728:Hormones / Q000494:pharmacology; D006801:Humans; D066298:In Vitro Techniques; D007306:Insecticides / Q000633:toxicity*; D008731:Methoxychlor / Q000633:toxicity; D011944:Receptors, Androgen / Q000187:drug effects*; D011960:Receptors, Estrogen / Q000187:drug effects*; D011980:Receptors, Progesterone / Q000187:drug effects*; D015203:Reproducibility of Results; D012441:Saccharomyces cerevisiae / Q000187:drug effects* / Q000235:genetics; D012680:Sensitivity and Specificity; D014158:Transcription, Genetic
chemical_list: D004785:Environmental Pollutants; D006728:Hormones; D007306:Insecticides; D011944:Receptors, Androgen; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; C014290:hydroxyflutamide; D005485:Flutamide; D003634:DDT; D008731:Methoxychlor