title: Congener-specific action of PBDEs on steroid secretion, CYP17, 17β-HSD and CYP19 activity and protein expression in porcine ovarian follicles.
abstract: The available data on reproductive toxicity of PBDEs are limited. In the present study we evaluated the direct effects of BDE-47, -99 and -100 on porcine ovarian follicular steroid secretions and the activity and expression of enzymes involved in its synthesis. Follicles were exposed to BDE-47 (0.5, 25 and 50 ng/ml), BDE-99 (0.25, 10 and 17.5 ng/ml), or BDE-100 (0.1, 4 and 12.5 ng/ml) for 24h. Progesterone (P4), androstenedione (A4), testosterone (T) and estradiol (E2) levels in the media were determined by EIA. CYP17, 17β-hydroxysteroid dehydrogenase (17β-HSD) and CYP19 activity was measured by conversion of P4>A4, A4>T and T to E2, respectively. Protein expression of CYP17, 17β-HSD and CYP19 was measured by western blot. All of the congeners explored in this study increase testosterone secretion. However, in the case of BDE-47 due to activation of 17 β-HSD and BDE-100 due to activation of CYP17, a corresponding failure to activate CYP19 expression and inhibition of CYP19 activity was seen. The lack of an effect of BDE-99 on the expression and activity of all of the investigated enzymes indicates action on enzymes before progesterone secretion, i.e., STAR or 3β-HSD activity.
authors.affiliation: Department of Physiology and Toxicology of Reproduction, Institute of Zoology, Jagiellonian University, Gronostajowa 9, 30-387 Krakow, Poland.
authors.forename: A
authors.initials: A
authors.lastname: Karpeta
authors.forename: A
authors.initials: A
authors.lastname: Rak-Mardyła
authors.forename: J
authors.initials: J
authors.lastname: Jerzak
authors.forename: E L
authors.initials: EL
authors.lastname: Gregoraszczuk
mesh_terms: D015067:17-Hydroxysteroid Dehydrogenases / Q000378:metabolism*; D000818:Animals; D001141:Aromatase / Q000378:metabolism*; D005260:Female; D012739:Gonadal Steroid Hormones / Q000378:metabolism*; D055768:Halogenated Diphenyl Ethers / Q000633:toxicity*; D011075:Polybrominated Biphenyls / Q000633:toxicity; D013254:Steroid 17-alpha-Hydroxylase / Q000378:metabolism*; D013552:Swine
chemical_list: C477694:2,2',4,4',5-brominated diphenyl ether; D012739:Gonadal Steroid Hormones; D055768:Halogenated Diphenyl Ethers; D011075:Polybrominated Biphenyls; C517827:pentabrominated diphenyl ether 100; C511295:2,2',4,4'-tetrabromodiphenyl ether; D015067:17-Hydroxysteroid Dehydrogenases; C044256:3 (or 17)-beta-hydroxysteroid dehydrogenase; D001141:Aromatase; D013254:Steroid 17-alpha-Hydroxylase