title: Hydroxylated polychlorinated biphenyls (OH-PCBs) induce vitellogenin through estrogenic activity in primary-cultured hepatocytes of the Xenopus laevis.
abstract: Vitellogenin (VTG)-inducing activities of 21 kinds of hydroxylated polychlorinated biphenyls (OH-PCBs) were investigated by an assay system using the primary-cultured hepatocyte of the adult male Xenopus laevis. An enzyme-linked immunoabsorbent assay (ELISA) was able to detect VTG at a minimum detection limit of 0.2ngmL(-1). The levels of VTG production in hepatocytes of male X. laevis exposed to six kinds of OH-PCB isomers (2'-OH-CB30, 3'-OH-CB30, 4'-OH-CB30, 4'-OH-CB50, 4'-OH-CB61 4'-OH-CB65) were significantly higher as compared to the control group (p<0.05). The relative ranking of the OH-PCBs was E2 (100%), 4'-OH-CB30 (2.0%)>2'-OH-CB30 (0.15%)>4'-OH-CB61 (0.046%)>3'-OH-CB30 (0.013%)>4'-OH-CB50 (0.002%)>4'-OH-CB65 (0.0001%). Although there were some differences between the estrogenicity values by the VTG-inducing activities and yeast two-hybrid assay for human estrogen receptor alpha (ERalpha). The results from VTG-assays suggested that an important factor for determining estrogenicity is the positions of the hydroxyl group and chlorine with the highest activity resulting from a para-hydroxyl group. The OH-PCB structures of high rank order in the VTG-assay had no chlorine substituted phenolic ring. Moreover, the meta-chlorine substituted phenolic ring is an important factor in determining estrogenicity. The OH-PCBs with meta-chlorine substituted phenolic ring did not show estrogenicity during VTG-assay.
authors.affiliation: Prefectural University of Kumamoto, Tsukide, Japan.
authors.forename: Kei
authors.initials: K
authors.lastname: Nomiyama
authors.forename: Yuji
authors.initials: Y
authors.lastname: Nomura
authors.forename: Tohru
authors.initials: T
authors.lastname: Takahashi
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Uchiyama
authors.forename: Koji
authors.initials: K
authors.lastname: Arizono
authors.forename: Ryota
authors.initials: R
authors.lastname: Shinohara
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D002713:Chlorine / Q000737:chemistry; D052244:Endocrine Disruptors / Q000633:toxicity*; D004797:Enzyme-Linked Immunosorbent Assay; D047628:Estrogen Receptor alpha / Q000378:metabolism; D022781:Hepatocytes / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D006878:Hydroxides / Q000737:chemistry; D008297:Male; D011078:Polychlorinated Biphenyls / Q000737:chemistry / Q000633:toxicity*; D020798:Two-Hybrid System Techniques; D014819:Vitellogenins / Q000096:biosynthesis*; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000633:toxicity*; D014982:Xenopus laevis / Q000378:metabolism*
chemical_list: D052244:Endocrine Disruptors; D047628:Estrogen Receptor alpha; D006878:Hydroxides; D014819:Vitellogenins; D014874:Water Pollutants, Chemical; D002713:Chlorine; D011078:Polychlorinated Biphenyls