Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
Antiestrogenicity of beta-naphthoflavone and PAHs in cultured rainbow trout hepatocytes: evidence for a role of the arylhydrocarbon receptor
Autore:
Navas, JM; Segner, H;
Indirizzi:
Umweltforschungszentrum Leipzig Halle, Sekt Chem Okotoxikol, D-04318 Leipzig, Germany Umweltforschungszentrum Leipzig Halle Leipzig Germany D-04318g, Germany
Titolo Testata:
AQUATIC TOXICOLOGY
fascicolo: 1, volume: 51, anno: 2000,
pagine: 79 - 92
SICI:
0166-445X(200011)51:1<79:AOBAPI>2.0.ZU;2-Z
Fonte:
ISI
Lingua:
ENG
Soggetto:
HUMAN BREAST-CANCER; 17-BETA-ESTRADIOL-INDUCED VITELLOGENIN SYNTHESIS; NUCLEAR ESTROGEN-RECEPTOR; MYKISS LIVER-CELLS; ONCORHYNCHUS-MYKISS; ALPHA-NAPHTHOFLAVONE; AH-RECEPTOR; 2,3,7,8-TETRACHLORODIBENZO-P-DIOXIN TCDD; HEPA-1C1C7 CELLS; GENE-EXPRESSION;
Keywords:
antiestrogenicity; vitellogenin; hepatocytes; polynuclear aromatic hydrocarbons (PAHs); arylhydrocarbon receptor; cytochrome P450 1A;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Agriculture,Biology & Environmental Sciences
Citazioni:
47
Recensione:
Indirizzi per estratti:
Indirizzo: Segner, H Umweltforschungszentrum Leipzig Halle, Sekt Chem Okotoxikol, Permoserstr 15, D-04318 Leipzig, Germany Umweltforschungszentrum Leipzig HallePermoserstr 15 Leipzig Germany D-04318
Citazione:
J.M. Navas e H. Segner, "Antiestrogenicity of beta-naphthoflavone and PAHs in cultured rainbow trout hepatocytes: evidence for a role of the arylhydrocarbon receptor", AQUAT TOX, 51(1), 2000, pp. 79-92

Abstract

The aims of the present study were to assess, (1) if polyaromatic hydrocarbons (PAHs) are able to inhibit estradiol-regulated vitellogenin synthesis in fish; and (2) if this antiestrogenic activity is mediated through the binding of PAHs to the arylhydrocarbon receptor (AhR). Cultured liver cells of rainbow trout, Oncorhynchus mykiss, were co-exposed to PAHs and 17 beta-estradiol (E2), and the resulting effects on induction of AhR-regulated 7-ethoxyresorufin-O-deethylase (EROD) activity and on E2-regulated vitellogenesis were investigated. The following test compounds were compared: the PAH 3-methylcholanthrene (3MC), which is a strong EROD inducer, the PAH anthracene (ANT), which is not an inducer of EROD activity, and the model EROD inducer, beta-naphthoflavone (beta NF). 3MC and beta NF led to significant decreases of E2-triggered hepatocellular VTG synthesis, whereas ANT exerted no antiestrogenic activity. The rank order of the antiestrogenic activity of the test substances agreed with their EROD-inducing potency suggesting that their antiestrogenicity might be mediated through the AhR. Further evidencefor this assumption comes from the observation that inhibitors such as alpha-naphthoflavone which interferes with ligand-AhR binding, and 8-methoxypsoralen (8MP), which prevents binding of the occupied AhR to responsive DNA elements, clearly reduced the antiestrogenic effects of the xenobiotics. Furthermore, from the comparison of estradiol concentrations in media of liver cells exposed to the CYP 1A-inducing agents and in media of control cellsit is unlikely that the observed antiestrogenic effects were caused by an enhanced E2 catabolism. In conclusion, the results from this study indicatethat, (1) AhR-binding PAHs possess ail antiestrogenic activity; and (2) that the antiestrogenic activity is mediated through the AhR. (C) 2000 Elsevier Science B.V. All rights reserved.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 25/11/20 alle ore 06:45:00