摘要
为了研究黄体酮对水生生物的生态毒理效应,以斑马鱼为试验材料,研究黄体酮对斑马鱼早期胚胎发育阶段下丘脑-垂体-生长轴相关基因转录表达的影响。将斑马鱼胚胎分别暴露在含0、6、45和90 ng/L的黄体酮水环境中144 hpf(hours post fertilization,受精后)。结果显示:黄体酮在不同暴露时间点可以调节生长激素释放激素(ghrh)基因的转录表达,可以诱导生长激素(gh)和胰岛素生长因子1受体a(igf1ra)基因的转录表达,但抑制了胰岛素生长因子2(igf2a、igf2b)和胰岛素生长因子1受体b(igf1rb)基因的转录表达。此外,黄体酮暴露对生长激素受体(ghra、ghrb)和胰岛素生长因子1(igf1)基因的转录表达没有显著影响。试验表明黄体酮能够改变斑马鱼早期胚胎发育阶段下丘脑-垂体-生长轴相关基因的转录表达水平,进而对斑马鱼的生长发育具有潜在的危险。
Progesterone is widely present in surface waters and wastewaters from farms. In order to assess the adverse effects of progesterone on aquatic organisms, zebrafish(Danio rerio) embryos as experimental organism were exposed to 0, 6, 45 and 90 ng/L progesterone for 144 hpf(hours post fertilization) to conduct the gene transcriptional alterations along the hypothalamic-pituitary-growth axis. The results showed that progesterone could mediate mRNA expression of growth hormone-releasing hormone(ghrh) gene at different exposure time points. Progesterone exposure led to a significant up-regulation of growth hormone(gh) and insulin-like growth factor 1 receptor alpha(igf1 ra) genes. However, transcriptional expression of insulin-like growth factor 2(igf2 a, igf2 b) and insulin-like growth factor 1 receptor beta(igf1 rb) genes were inhibited by progesterone. In addition, progesterone treatment had no significant effects on the transcriptional profiles of target genes associated with growth hormone receptor(ghra, ghrb) and insulin-like growth factor 1(igf1) genes.Taken together, the overall results demonstrated that progesterone could significantly affect transcriptional expression levels of genes related to hypothalamic-pituitary-growth axis, which may pose potential adverse effects to the growth of zebrafish.
引文
[1]Kloas W,Urbatzka R,Opitz R,et al.Endocrine disruption in aquatic vertebrates[R].In Vaudry H,Roubos EW,Coast GM,Vallarino M,eds,Trends in Comparative Endocrinology and Neurobiology.Vol1163-Annals of the New York Academy of Sciences,2009,187-200.
[2]Oshima Y,Kang I J,Kobayashi M,et al.Suppression of sexual behavior in male Japanese medaka(Oryzias latipes)exposed to17β-estradiol[J].Chemosphere,2003,50(3):429-436.
[3]Schulz R W,Bogerd J,Male R,et al.Estrogen-induced alterations in amh and dmrt1 expression signal for disruption in male sexual development in the zebrafish[J].Environmental Science&Technology,2007,41(17):6305-6310.
[4]Fent K.Progestins as endocrine disrupters in aquatic ecosystems:Concentrations,effects and risk assessment[J].Environment International,2015,84:115-130.
[5]Kumar V,Johnson AC,Trubiroha A,et al.The challenge presented by progestins in ecotoxicological research:a critical review[J].Environ Sci Technol,2015,49(5):2625-2638.
[6]Liu S,Ying G-G,Zhang R-Q,et al.Fate and occurrence of steroids in swine and dairy cattle farms with different farming scales and wastes disposal systems[J].Environmental Pollution,2012 170:190-201.
[7]Liu S,Ying G G,Zhou L J,et al.Steroids in a typical swine farm and their release into the environment[J].Water Research,2012,46(12):3754-3768.
[8]DeQuattro ZA,Peissig EJ,Antkiewicz DS,et al.Effects of progesterone on reproduction and embryonic development in the fathead minnow(Pimephales promelas)[J].Environmental Toxicology and Chemistry,2012,31:851-856.
[9]Murack P J,Parrish J,Barry T P.Effects of progesterone on sperm motility in fathead minnow(Pimephales promelas)[J].Aquatic Toxicology,2011,104:121-125.
[10]Zucchi S,Castiglioni S,Fent K.Progestins and antiprogestins affect gene expression in early development in zebrafish(Danio rerio)at environmental concentrations[J].Environmental Science&Technology,2012,46:5183-5192.
[11]Zucchi S,Castiglioni S,Fent K.Progesterone alters global transcription profiles at environmental concentrations in brain and ovary of female zebrafish(Danio rerio)[J].Environmental Science&Technology,2013,47(21):12548-12556.
[12]Zucchi S,Mirbahai L,Castiglioni S,et al.Transcriptional and physiological responses induced by binary mixtures of drospirenone and progesterone in zebrafish(Danio rerio)[J].Environmental Science&Technology,2014,48(6):3523-3531.
[13]Liang Y Q,Huang G Y,Liu S S,et al.Long-term exposure to environmentally relevant concentrations of progesterone and norgestrel affects sex differentiation in zebrafish(Danio rerio)[J].Aquatic Toxicology,2015,160:172-179.
[14]Liang Y Q,Huang G Y,Ying G G,et al.Progesterone and norgestrel alter transcriptional expression of genes along the hypothalamicpituitary-thyroid axis in zebrafish embryos-larvae[J].Comparative Biochemistry and Physiology Part C:Toxicology&Pharmacology,2015,167:101-107.
[15]Liang Y Q,Huang G Y,Ying G G,et al.The effects of progesterone on transcriptional expression profiles of genes associated with hypothalamicpituitary-gonadal and hypothalamic-pituitary-adrenal axes during the early development of zebrafish(Danio rerio)[J].Chemosphere,2015,128:199-206.
[16]Livak K J,Schmittgen T D.Analysis of relative gene expression data using real-time quantitative PCR and the 2-ΔΔCt method[J].Methods,2001,25(4):402-408.