Accumulation and Biotransformation of BDE-47 by Zebrafish Larvae and Teratogenicity and Expression of Genes along the Hypothalamus-Pituitary-Thyroid Axis
- Authors
- Zheng, X., Zhu, Y., Liu, C., Liu, H., Giesy, J.P., Hecker, M., Lam, M.H., and Yu, H.
- ID
- ZDB-PUB-121120-16
- Date
- 2012
- Source
- Environmental science & technology 46(23): 12943-12951 (Journal)
- Registered Authors
- Keywords
- none
- MeSH Terms
-
- Animals
- Embryo, Nonmammalian/abnormalities
- Embryo, Nonmammalian/drug effects
- Embryo, Nonmammalian/metabolism
- Halogenated Diphenyl Ethers
- Hypothalamus/drug effects
- Hypothalamus/metabolism
- Larva/drug effects
- Larva/genetics
- Larva/metabolism
- Pituitary Gland/drug effects
- Pituitary Gland/metabolism
- Polybrominated Biphenyls/chemistry
- Polybrominated Biphenyls/metabolism*
- Thyroid Gland/drug effects
- Thyroid Gland/metabolism
- Transcriptome/drug effects
- Water Pollutants, Chemical/chemistry
- Water Pollutants, Chemical/metabolism*
- Zebrafish/embryology
- Zebrafish/genetics*
- Zebrafish/metabolism*
- PubMed
- 23110413 Full text @ Env. Sci. Tech.
- CTD
- 23110413
Accumulation and effects of BDE-47 and two analogues, 6-OH-BDE-47 and 6-MeO-BDE-47, on ontogeny and profiles of transcription of genes along the hypothalamus–pituitary–thyroid (HPT) axis of zebrafish (Danio rerio) embryos exposed from 4 h post fertilization (hpf) to 120 hpf were investigated. The 96 h-LC50 of the most toxic compound, based on teratogenicity, was 330 µg of 6-OH-BDE-47/L. 6-OH-BDE-47 significantly down-regulated expression of mRNA of thyroid stimulating hormone receptor (TSHR), thyroid hormone receptors (TRs, including TRα and TRβ), sodium/iodide symporter (NIS), and transthyretin (TTR) while up-regulating expression of thyroglobulin (TG) and thyrotropin-releasing hormone (TRH). Spontaneous movement was affected by 1 mg of 6-OH-BDE-47/L or 5 mg of 6-MeO-BDE-47/L. BDE-47 did not alter activity of larvae at any concentration tested. 6-MeO-BDE-47 significantly up-regulated expression of mRNA of TRH, TRα, TRβ and NIS. Both 6-OH-BDE-47 and 6-MeO-BDE-47 affected the thyroid hormone pathway. BDE-47 and 6-MeO-BDE-47 were accumulated more than 6-OH-BDE-47. 6-MeO-BDE-47 was transformed into 6-OH-BDE-47, but BDE-47 was not transformed into it. In summary, the synthetic brominated flame retardant, BDE-47, did not elicit the adverse effects caused by the other two analogues and appeared to have less toxicological relevance than the two natural product analogues 6-OH- and 6-MeO-BDE-47.