title: Steroid secretion following exposure of ovarian follicular cells to three different natural mixtures of persistent organic pollutants (POPs).
abstract: This study investigated in vitro endocrine disrupting effects of three mixtures of POPs: 'Marine mix' extracted from Atlantic cod liver, and two mixtures extracted from burbot liver, 'Mjøsa mix' and 'Losna mix'. The POP mixtures were chemically characterized. Co-culture of theca and granulosa cells, were exposed for 48h with different doses of 'Marine mix', 'Mjøsa mix' or 'Losna mix'. As an end point cell viability was determinated by LDH test, steroid analysis by EIA and caspase-3 by colorimetric substrate. Chemical characterization of the mixtures demonstrated that the 'Marine mix' contained high levels of DDTs and PCBs. In the 'Mjøsa mix', the dominant pollutants were BDEs and HBCD. The concentrations of POPs measured in the 'Losna mix' were considerably lower. All mixtures used in the present study had a stimulatory effect on testosterone and estradiol secretion with 'Marine mix'>'Mjøsa mix'>'Losna mix'. These results show that even a mixture containing background concentrations of POPs significantly affected steroid secretion. A higher steroidogenic response in low dose ranges, compared with high dose ranges indicated xenobiotic-conditioning hormesis. This could complicate predictions of effects in risk assessments.
authors.affiliation: Department of Physiology and Toxicology of Reproduction, Institute of Zoology, Jagiellonian University, Ingardena 6, 30-060 Kraków, Poland. greg@zuk.iz.uj.edu.pl
authors.forename: Ewa L
authors.initials: EL
authors.lastname: Gregoraszczuk
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Milczarek
authors.forename: Anna K
authors.initials: AK
authors.lastname: Wójtowicz
authors.forename: Vidar
authors.initials: V
authors.lastname: Berg
authors.forename: Janneche U
authors.initials: JU
authors.lastname: Skaare
authors.forename: Erik
authors.initials: E
authors.lastname: Ropstad
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D053148:Caspase 3 / Q000378:metabolism; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D018920:Coculture Techniques; D003060:Cod Liver Oil / Q000737:chemistry / Q000633:toxicity; D004305:Dose-Response Relationship, Drug; D052244:Endocrine Disruptors / Q000737:chemistry* / Q000302:isolation & purification; D004958:Estradiol / Q000378:metabolism; D005260:Female; D029941:Fish Proteins / Q000378:metabolism; D048388:Gadiformes; D048389:Gadus morhua; D012739:Gonadal Steroid Hormones / Q000378:metabolism*; D006107:Granulosa Cells / Q000187:drug effects* / Q000378:metabolism; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D009664:Norway; D011374:Progesterone / Q000378:metabolism; D018570:Risk Assessment; D013552:Swine; D013799:Theca Cells / Q000187:drug effects* / Q000378:metabolism; D013997:Time Factors; D014874:Water Pollutants, Chemical / Q000302:isolation & purification / Q000633:toxicity*
chemical_list: D052244:Endocrine Disruptors; D029941:Fish Proteins; D012739:Gonadal Steroid Hormones; D014874:Water Pollutants, Chemical; D011374:Progesterone; D004958:Estradiol; D003060:Cod Liver Oil; D007770:L-Lactate Dehydrogenase; D053148:Caspase 3