title: Short-term treatment of adult male zebrafish (Danio Rerio) with 17α-ethinyl estradiol affects the transcription of genes involved in development and male sex differentiation.
abstract: The synthetic estrogen 17α-ethinyl estradiol (EE2) disturbs reproduction and causes gonadal malformation in fish. Effects on the transcription of genes involved in gonad development and function that could serve as sensitive biomarkers of reproductive effects in the field is, however, not well known. We have studied mRNA expression in testes and liver of adult zebrafish (Danio rerio) males treated with 0, 5 or 25 ng/L EE2for 14 days. qPCR analysis showed that the mRNA expression of four genes linked to zebrafish male sex determination and differentiation, Anti-Mullerian Hormone, Double sex and mab-related protein, Sry-related HMG box-9a and Nuclear receptor subfamily 5 group number 1b were significantly decreased by 25 ng/L, but not 5 ng/L EE2 compared with the levels in untreated fish. The decreased transcription was correlated with a previously shown spawning failure in these males (Reyhanian et al., 2011. Aquat Toxicol 105, 41-48), suggesting that decreased mRNA expression of genes regulating male sexual function could be involved in the functional sterility. The mRNA level of Cytochrome P-45019a, involved in female reproductive development, was unaffected by hormone treatment. The transcription of the female-specific Vitellogenin was significantly induced in testes. While testicular Androgen Receptor and the Estrogen Receptor-alpha mRNA levels were unchanged, Estrogen receptor-beta was significantly decreased by 25 ng/L EE2. Hepatic Estrogen Receptor-alpha mRNA was significantly increased by both exposure concentrations, while Estrogen Receptor-beta transcription was unaltered. The decreased transcription of male-predominant genes supports a demasculinization of testes by EE2 and might reflect reproductive disturbances in the environment.
authors.affiliation: School of Natural Sciences, Technology and Environmental Studies, Södertörn University, SE-141 89 Huddinge, Sweden; Örebro Life Science Center, School of Science and Technology, Örebro University, SE-701 82 Örebro, Sweden. Electronic address: nasim.caspillo@sh.se.
authors.forename: Nasim
authors.initials: N
authors.lastname: Reyhanian Caspillo
authors.affiliation: School of Natural Sciences, Technology and Environmental Studies, Södertörn University, SE-141 89 Huddinge, Sweden; Örebro Life Science Center, School of Science and Technology, Örebro University, SE-701 82 Örebro, Sweden.
authors.forename: Kristina
authors.initials: K
authors.lastname: Volkova
authors.affiliation: School of Natural Sciences, Technology and Environmental Studies, Södertörn University, SE-141 89 Huddinge, Sweden.
authors.forename: Stefan
authors.initials: S
authors.lastname: Hallgren
authors.affiliation: Örebro Life Science Center, School of Science and Technology, Örebro University, SE-701 82 Örebro, Sweden.
authors.forename: Per-Erik
authors.initials: PE
authors.lastname: Olsson
authors.affiliation: School of Natural Sciences, Technology and Environmental Studies, Södertörn University, SE-141 89 Huddinge, Sweden.
authors.forename: Inger
authors.initials: I
authors.lastname: Porsch-Hällström
mesh_terms: D000818:Animals; D054304:Anti-Mullerian Hormone / Q000235:genetics; D001141:Aromatase / Q000235:genetics; D004781:Environmental Exposure; D047629:Estrogen Receptor beta / Q000235:genetics; D004997:Ethinyl Estradiol / Q000633:toxicity*; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects*; D008099:Liver / Q000187:drug effects / Q000502:physiology; D008297:Male; D055758:SOX9 Transcription Factor / Q000235:genetics; D012733:Sex Differentiation / Q000187:drug effects; D054339:Steroidogenic Factor 1 / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics; D014819:Vitellogenins / Q000235:genetics; D014874:Water Pollutants, Chemical / Q000633:toxicity; D015027:Zebrafish / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D029961:Zebrafish Proteins / Q000235:genetics
chemical_list: C110547:DMRT1 protein; D047629:Estrogen Receptor beta; D055758:SOX9 Transcription Factor; C504918:Sox9a protein, zebrafish; D054339:Steroidogenic Factor 1; D014157:Transcription Factors; D014819:Vitellogenins; D014874:Water Pollutants, Chemical; D029961:Zebrafish Proteins; D004997:Ethinyl Estradiol; D054304:Anti-Mullerian Hormone; D001141:Aromatase; C440729:Cyp19a1a protein, zebrafish
keywords: 17α-Ethinyl estradiol; Biomarker; Endocrine disruptors; Gene regulation; Gonads; Sex differentiation; Zebrafish