Vitellogenin-inducing activities of natural, synthetic, and environmental estrogens in primary cultured Xenopus laevis hepatocytes.
Vitellogenin (VTG)-inducing activities of natural estrogens (E1: estrone, E2:17beta-estradiol, E3: estriol, alpha-E2: 17alpha-estradiol), synthetic estrogens (EE2: 17alpha-ethynyl estradiol, DES: diethylstilbestrol,), phytoestrogen (GEN: genistein), and xeno-estrogens (BPA: bisphenol A, NP: nonylphenol, OP: octylphenol) were investigated by an assay system using primary-cultured hepatocytes of Xenopus laevis. An enzyme-linked immunoabsorbent assay (ELISA) was able to detect VTG at a minimum detection limit of 0.06 ng/mL. Relative estrogenic activities of the compounds were determined from their dose-response curves. The activities relative to E2 activity were 138% for DES, 121% for EE2, 6.1% for E3, 0.33% for E1, 0.29% for alpha-E2, 0.037% for GEN, 0.008% for BPA, 0.005% for NP, and 0.002% for OP. Comparison with data reported for other bioassay systems revealed that there were significant interspecies-and cell-type-differences in the activities of DES, E3, E1 and alpha-E2. BPA was found to have a substantial antagonistic activity (approximately 0.8% of tamoxifen activity) under the influence of physiological concentrations of E2. Complex-effects of endocrine disrupters on aquatic animals will be discussed.
Mitsui
Naoko
N
Biotechnology Research Laboratory, Towa Environment Science Co., Ltd., Hiroshima 730-0841, Japan.
Tooi
Osamu
O
Kawahara
Akira
A
D000818:Animals; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D052244:Endocrine Disruptors / Q000145:classification / Q000494:pharmacology*; D004785:Environmental Pollutants / Q000494:pharmacology; D004797:Enzyme-Linked Immunosorbent Assay; D045166:Estradiol Congeners / Q000145:classification / Q000494:pharmacology*; D022781:Hepatocytes / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D048789:Phytoestrogens / Q000145:classification / Q000494:pharmacology*; D014818:Vitellogenesis / Q000187:drug effects / Q000502:physiology; D014819:Vitellogenins / Q000378:metabolism*; D014982:Xenopus laevis / Q000502:physiology*
D052244:Endocrine Disruptors; D004785:Environmental Pollutants; D045166:Estradiol Congeners; D048789:Phytoestrogens; D014819:Vitellogenins