title: Bisphenol A affects gene expression of gonadotropin-releasing hormones and type I GnRH receptors in brains of adult rare minnow Gobiocypris rarus.
abstract: Recent studies support the notion that endocrine disrupting chemicals (EDCs) could affect the reproductive regulations of the neuroendocrine system. The objectives of the present study were to determine whether the weak estrogenic chemical, bisphenol A (BPA), disrupts gonadotropin-releasing hormone (GnRH) system by altering the transcription of GnRHs and GnRH receptor (GnRHR) genes in adult rare minnow Gobiocypris rarus. In the present study, the histological examination of the ovary after 35-day BPA exposure at 15 μg/L demonstrated the perturbing effects of environmentally relevant BPA on the ovarian development in G. rarus. In addition mRNA expression of ovarian P450 aromatase in both ovaries and testes were significantly down-regulated by 15 μg/L BPA. GnRH2, GnRH3, GnRHR1A and GnRHR1B gene were identified in G. rarus. The expression patterns of GnRHs and GnRHR1s were analyzed in various tissues of G. rarus by quantitative real-time PCR. GnRHs and GnRHR1s were all predominantly expressed in the brains. Both GnRH3 and GnRHR1A were significantly upregulated in the brains of female exposed to 15 μg/L BPA for 35 days. It would suggest a potential negative feedback in the GnRH system in response to the disturbance of downstream of the brain-pituitary-gonadal axis. Collectively, the present findings suggest that the transcripts of some key genes in the neuroendocrine system can be used as critical biomarkers in endocrine disruption assays of teleost fish.
authors.affiliation: College of Animal Science and Technology, Northwest A&F University, Shaanxi Key Laboratory of Molecular Biology for Agriculture, Yangling, Shaanxi 712100 China.
authors.forename: Fang
authors.initials: F
authors.lastname: Qin
authors.forename: Lihong
authors.initials: L
authors.lastname: Wang
authors.forename: Xueqin
authors.initials: X
authors.lastname: Wang
authors.forename: Shaozhen
authors.initials: S
authors.lastname: Liu
authors.forename: Peng
authors.initials: P
authors.lastname: Xu
authors.forename: Houpeng
authors.initials: H
authors.lastname: Wang
authors.forename: Tingting
authors.initials: T
authors.lastname: Wu
authors.forename: Yingying
authors.initials: Y
authors.lastname: Zhang
authors.forename: Yao
authors.initials: Y
authors.lastname: Zheng
authors.forename: Meng
authors.initials: M
authors.lastname: Li
authors.forename: Xia
authors.initials: X
authors.lastname: Zhang
authors.forename: Cong
authors.initials: C
authors.lastname: Yuan
authors.forename: Guojun
authors.initials: G
authors.lastname: Hu
authors.forename: Zaizhao
authors.initials: Z
authors.lastname: Wang
mesh_terms: D000818:Animals; D001141:Aromatase / Q000235:genetics; D001559:Benzhydryl Compounds / Q000633:toxicity*; D001921:Brain / Q000187:drug effects* / Q000378:metabolism; D003530:Cyprinidae / Q000235:genetics*; D004968:Estrogens, Non-Steroidal / Q000633:toxicity; D005260:Female; D029941:Fish Proteins / Q000145:classification / Q000235:genetics; D015870:Gene Expression / Q000187:drug effects*; D020869:Gene Expression Profiling; D007987:Gonadotropin-Releasing Hormone / Q000145:classification / Q000235:genetics*; D008297:Male; D010053:Ovary / Q000187:drug effects / Q000378:metabolism; D010636:Phenols / Q000633:toxicity*; D010802:Phylogeny; D020033:Protein Isoforms / Q000145:classification / Q000235:genetics; D011966:Receptors, LHRH / Q000145:classification / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013737:Testis / Q000187:drug effects / Q000378:metabolism; D013997:Time Factors; D000098826:Bisphenol A Compounds
chemical_list: D001141:Aromatase; D001559:Benzhydryl Compounds; D004968:Estrogens, Non-Steroidal; D029941:Fish Proteins; D007987:Gonadotropin-Releasing Hormone; D010636:Phenols; D020033:Protein Isoforms; D011966:Receptors, LHRH; C006780:bisphenol A; D000098826:Bisphenol A Compounds