title: The endocrine effects of dietary brominated diphenyl ether-47 exposure, measured across multiple levels of biological organization, in breeding fathead minnows.
abstract: The goal of the present study was to evaluate the reproductive function of fathead minnows (Pimephales promelas) exposed to brominated diphenyl ether-47 (BDE-47) at doses lower than those used in previous studies. This was accomplished by evaluating the impacts of BDE-47 exposures across multiple levels of biological organization. Breeding pairs were exposed to BDE-47 via diet for 21 d, during which reproductive success was monitored. At the conclusion of the exposure, fish were euthanized to assess the effects of BDE-47 on sex steroid-related and thyroid-related transcripts, plasma androgen levels, gonadosomatic index (GSI), and secondary sexual characteristics. Several alterations in gene expression were noted including a >2.1-fold decrease in hepatic estrogen receptor α (erα) and a 2.9-fold decrease in ovarian aromatase (arom). In addition, BDE-47-exposed males experienced increases in deiodinase 2 (dio2) expression in brain tissue (∼1.5-fold) and decreases in hepatic transthyretin (ttr) expression (∼1.4-fold). Together, these gene expression alterations suggest the potential for BDE-47 to disrupt endocrine signaling. There were no significant differences in plasma hormone levels, GSI, secondary sexual characteristics, or reproductive success. Overall, the present study demonstrates that exposure to BDE-47 is capable of altering both sex steroid-related and thyroid-related transcripts but that these observed alterations do not necessarily manifest themselves at higher levels of biological organization for the endpoints selected. Environ Toxicol Chem 2016;35:2048-2057. © 2016 SETAC.
authors.affiliation: Department of Biology, Texas Christian University, Fort Worth, Texas, USA.
authors.forename: Leah M
authors.initials: LM
authors.lastname: Thornton
authors.affiliation: Department of Biology, Texas Christian University, Fort Worth, Texas, USA.
authors.forename: Elise M
authors.initials: EM
authors.lastname: Path
authors.affiliation: Department of Biological Sciences, University of North Texas, Denton, Texas, USA.
authors.forename: Barney J
authors.initials: BJ
authors.lastname: Venables
authors.affiliation: Department of Biology, Texas Christian University, Fort Worth, Texas, USA.
authors.forename: Marlo K
authors.initials: MK
authors.lastname: Sellin Jeffries
mesh_terms: D000821:Animal Feed; D000818:Animals; D001921:Brain / Q000187:drug effects / Q000378:metabolism; D001947:Breeding; D003530:Cyprinidae / Q000097:blood / Q000235:genetics / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D052244:Endocrine Disruptors / Q000633:toxicity*; D004784:Environmental Monitoring / Q000379:methods*; D005260:Female; D015870:Gene Expression / Q000187:drug effects; D012739:Gonadal Steroid Hormones / Q000378:metabolism; D055768:Halogenated Diphenyl Ethers / Q000633:toxicity*; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D008297:Male; D012098:Reproduction / Q000187:drug effects*; D013963:Thyroid Hormones / Q000235:genetics / Q000378:metabolism
chemical_list: D052244:Endocrine Disruptors; D012739:Gonadal Steroid Hormones; D055768:Halogenated Diphenyl Ethers; D013963:Thyroid Hormones; C511295:2,2',4,4'-tetrabromodiphenyl ether
keywords: Brominated diphenyl ether 47; Fathead minnow; Gene expression; Polybrominated diphenyl ether 47; Reproduction