The polybrominated diphenyl ether mixture DE-71 is mildly estrogenic.
Environ Health Perspect
; 116(5): 605-11, 2008 May.
Article
em En
| MEDLINE
| ID: mdl-18470304
ABSTRACT
BACKGROUND:
Polybrominated diphenyl ethers (PBDEs) are widely found in the environment, and they may act as endocrine disruptors.OBJECTIVE:
Our goal in this study was to test the PBDE mixture DE-71 for estrogenic activity.METHODS:
We used proliferation of cultured breast cancer cells (MCF-7) and trophic effects in the reproductive tracts of ovariectomized mice as estrogen bioassays. DE-71 was administered to mice by subcutaneous injection (sc) or oral gavage (po), alone or in combination with estradiol, for 3 or 34 days. Liver weights and cytochrome P450 enzyme activities were also measured.RESULTS:
DE-71 increased MCF-7 cell proliferation, and this was prevented by antiestrogen. DE-71 cotreatment reduced the effect of estradiol in MCF-7 cells. In the mouse 3-day assay, DE-71 administered alone had no effect on uterine weight, uterine epithelial height (UEH), or vaginal epithelial thickness (VET); however, when DE-71 was administered as a cotreatment, it potentiated estradiol's effect on uterine weight. DE-71 administered sc to BALB/c mice for 34 days slightly increased UEH and VET, and attenuated the estradiol-induced increase in UEH; these effects were not seen in BALB/c mice treated po or in C57BL/6 mice treated sc. DE-71 increased liver weight in BALB/c, C57BL/6, and estrogen receptor-alpha knockout mice. We also found an increase in liver cytochrome P450 1A (CYP1A) and CYP2B activities when DE-71 was administered po, but only CYP2B increased after sc treatment.CONCLUSION:
DE-71 behaves as a weak estrogen. In mice, the treatment route and duration determined if DE-71 was estrogenic. BALB/c mice are more susceptible to DE-71 effects in estrogen target tissues than C57BL/6 mice. DE-71 increased liver weight independently of estrogen receptor-alpha.Palavras-chave
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Base de dados:
MEDLINE
Assunto principal:
Éteres Fenílicos
/
Bifenil Polibromatos
/
Moduladores de Receptor Estrogênico
Limite:
Animals
Idioma:
En
Ano de publicação:
2008
Tipo de documento:
Article