title: Effects of steroid hormones on reproduction- and detoxification-related gene expression in adult male mosquitofish, Gambusia affinis.
abstract: The molecular mechanisms that mediate fish reproduction and detoxification in response to steroid hormones were studied by using adult male western mosquitofish (Gambusia affinis) as sentinel species. The expression patterns of three vitellogenins (VtgA, VtgB and VtgC), two estrogen receptors (ERα and ERβ), two androgen receptors (ARα and ARβ), metallothionein (MT) and cytochrome P450 1A (CYP1A) in the liver and testis of adult male mosquitofish were assessed through exposure treatments with progesterone (P), testosterone (T) and 17β-estradiol (E2), alone and in combination for eight days. The results showed that expression patterns of Vtg subtype, ER subtype, AR subtype, MT and CYP1A genes in male mosquitofish varied according to tissue and specific hormone stress. Vtg subtype mRNA expression was induced in the liver in E2-added treatments, and an up-regulation of ERα mRNA expression was also observed. In addition, hormone treatments increased three Vtg subtype mRNA expression levels in the testis, at least to some extent. All hormone treatments significantly inhibited ERα, ERβ and ARβ mRNA expression in the testis. Some of hormone treatments could affect MT and CYP1A gene expression in mosquitofish. In general, multiple hormone treatments showed different effects on target gene expression compared with corresponding hormone alone. The results from the present study provided valuable information on the toxicological effects of steroid hormones in mosquitofish.
authors.affiliation: State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China. huang_gyh@sina.com
authors.forename: Guo-Yong
authors.initials: GY
authors.lastname: Huang
authors.forename: Guang-Guo
authors.initials: GG
authors.lastname: Ying
authors.forename: Yan-Qiu
authors.initials: YQ
authors.lastname: Liang
authors.forename: You-Sheng
authors.initials: YS
authors.lastname: Liu
authors.forename: Shuang-Shuang
authors.initials: SS
authors.lastname: Liu
mesh_terms: D000818:Animals; D003532:Cyprinodontiformes / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics; D004958:Estradiol / Q000494:pharmacology / Q000633:toxicity*; D015870:Gene Expression / Q000187:drug effects* / Q000235:genetics; D008658:Inactivation, Metabolic; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D008297:Male; D008668:Metallothionein / Q000096:biosynthesis / Q000235:genetics; D011374:Progesterone / Q000494:pharmacology / Q000633:toxicity*; D012333:RNA, Messenger / Q000235:genetics; D011944:Receptors, Androgen / Q000096:biosynthesis / Q000235:genetics; D011960:Receptors, Estrogen / Q000096:biosynthesis / Q000235:genetics; D012098:Reproduction / Q000187:drug effects* / Q000235:genetics; D013737:Testis / Q000187:drug effects / Q000378:metabolism; D013739:Testosterone / Q000494:pharmacology / Q000633:toxicity*; D015854:Up-Regulation / Q000187:drug effects; D014819:Vitellogenins / Q000096:biosynthesis / Q000235:genetics
chemical_list: D012333:RNA, Messenger; D011944:Receptors, Androgen; D011960:Receptors, Estrogen; D014819:Vitellogenins; D013739:Testosterone; D011374:Progesterone; D004958:Estradiol; D003577:Cytochrome P-450 Enzyme System; D008668:Metallothionein