title: A time-course transcriptional kinetics of the hypothalamic-pituitary-gonadal and hypothalamic-pituitary-adrenal axes in zebrafish eleutheroembryos after exposure to norgestrel.
abstract: The objective of the present study was to investigate the effects of norgestrel on the hypothalamic-pituitary-gonadal (HPG) and hypothalamic-pituitary-adrenal (HPA) axes in zebrafish eleutheroembryos. Zebrafish embryos were exposed to different concentrations of norgestrel (0 ng L(-1) , 5 ng L(-1) , 50 ng L(-1) , and 100 ng L(-1) ) for 144 h post fertilization (hpf), and the transcriptional profiles of the HPG and HPA axes were examined every day. Norgestrel modulated the expression of Pgr and Vtg1 messenger (m)RNAs mainly at 96 hpf for all treatment groups. In addition, norgestrel strongly altered the expression of Cyp11a1 mRNA above 5 ng L(-1) (significant upregulation from 48 hpf to 120 hpf and significant downregulation for 144 hpf). Norgestrel treatment could significantly induce expression of Cyp19a1a, Cyp11b, Gnrh2, Gnrh3, and Lhb mRNAs but inhibit transcripts of Hsd11b2 and Crh genes above 5 ng L(-1) at different time points. The transcriptional expression levels of Esr1, Ar, Star, Hsd17b3, Fshb, and Pomc were also mediated by 5 ng L(-1) norgestrel or higher during different exposure periods. Taken together, the overall results imply that the transcriptional changes in zebrafish eleutheroembryos may pose a potential effect on embryonic development, in particular in the brain and gonadogenesis.
authors.affiliation: State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, People's Republic of China.
authors.forename: Yan-Qiu
authors.initials: YQ
authors.lastname: Liang
authors.forename: Guo-Yong
authors.initials: GY
authors.lastname: Huang
authors.forename: Guang-Guo
authors.initials: GG
authors.lastname: Ying
authors.forename: Shuang-Shuang
authors.initials: SS
authors.lastname: Liu
authors.forename: Yu-Xia
authors.initials: YX
authors.lastname: Jiang
authors.forename: Shan
authors.initials: S
authors.lastname: Liu
authors.forename: Feng-Jiao
authors.initials: FJ
authors.lastname: Peng
mesh_terms: D000818:Animals; D006066:Gonads / Q000196:embryology / Q000502:physiology*; D007030:Hypothalamo-Hypophyseal System / Q000196:embryology / Q000502:physiology*; D009644:Norgestrel / Q000493:pharmacokinetics*; D010913:Pituitary-Adrenal System / Q000187:drug effects* / Q000196:embryology / Q000502:physiology; D011372:Progestins / Q000493:pharmacokinetics*; D015398:Signal Transduction; D014158:Transcription, Genetic; D015027:Zebrafish / Q000196:embryology / Q000235:genetics / Q000378:metabolism*
chemical_list: D011372:Progestins; D009644:Norgestrel
keywords: Gene transcription; Hypothalamic-pituitary-adrenal axis; Hypothalamic-pituitary-gonadal axis; Norgestrel; Zebrafish