The endocrine effects of dietary brominated diphenyl ether-47 exposure, measured across multiple levels of biological organization, in breeding fathead minnows

Autor: Elise M. Path, Leah M. Thornton, Barney J. Venables, Marlo K. Sellin Jeffries
Rok vydání: 2016
Předmět:
Zdroj: Environmental Toxicology and Chemistry. 35:2048-2057
ISSN: 0730-7268
DOI: 10.1002/etc.3351
Popis: 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.
Databáze: OpenAIRE