title: Waterborne exposure to fluorotelomer alcohol 6:2 FTOH alters plasma sex hormone and gene transcription in the hypothalamic-pituitary-gonadal (HPG) axis of zebrafish.
abstract: Fluorotelomer alcohols (FTOHs) have shown estrogenic activity in vitro and in vivo, but the mechanism of this activity is not known. In this study, 18-week-old zebrafish (Danio rerio) were exposed to 0, 0.03, 0.3 and 3.0mg/l 1H,1H,2H,2H-perfluorooctan-1-ol (6:2 FTOH) for 7 days, and the effects on plasma sex hormone levels were measured followed by use of real-time PCR to examine selected gene expression in hypothalamic-pituitary-gonadal (HPG) axis and liver. Exposure to 6:2 FTOH significantly increased plasma estradiol (E2) and testosterone (T) levels in both males and females. Furthermore, the ratio of T/E2 was reduced in females while increased in males. In females, the increase of E2 was accompanied by up-regulated hepatic estrogenic receptor alpha (ERalpha) and vitellogenin (VTG1 and VTG3) expression. In males, the elevation of the T level is consistent with the up-regulation of cytochrome P450 c17alpha-hydroxylase, 17, 20-lase (CYP17) and the down-regulation of cytochrome P450 aromatase A (CYP19A). The present study demonstrated that waterborne exposure to 6:2 FTOH alter plasma sex hormone levels and the ratio of T/E2, as well as the transcriptional profiles of some genes in the HPG axis and liver. The results suggested that FTOHs may disturb fish reproduction through endocrine disrupted activity.
authors.affiliation: Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China.
authors.forename: Chunsheng
authors.initials: C
authors.lastname: Liu
authors.forename: Liqin
authors.initials: L
authors.lastname: Yu
authors.forename: Jun
authors.initials: J
authors.lastname: Deng
authors.forename: Paul K S
authors.initials: PK
authors.lastname: Lam
authors.forename: Rudolf S S
authors.initials: RS
authors.lastname: Wu
authors.forename: Bingsheng
authors.initials: B
authors.lastname: Zhou
mesh_terms: D000818:Animals; D052244:Endocrine Disruptors / Q000633:toxicity*; D004781:Environmental Exposure; D004958:Estradiol / Q000097:blood; D004967:Estrogens / Q000633:toxicity*; D005260:Female; D005466:Fluorocarbons / Q000633:toxicity*; D015870:Gene Expression / Q000187:drug effects; D012739:Gonadal Steroid Hormones / Q000097:blood*; D007030:Hypothalamo-Hypophyseal System / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008297:Male; D013739:Testosterone / Q000097:blood; D014158:Transcription, Genetic / Q000187:drug effects*; D014874:Water Pollutants, Chemical / Q000633:toxicity*; D015027:Zebrafish / Q000097:blood / Q000235:genetics / Q000378:metabolism*
chemical_list: D052244:Endocrine Disruptors; D004967:Estrogens; D005466:Fluorocarbons; D012739:Gonadal Steroid Hormones; D014874:Water Pollutants, Chemical; C033729:fluorotelomer alcohols; D013739:Testosterone; D004958:Estradiol