RRC ID 31790
Author Oka T, Mitsui-Watanabe N, Tatarazako N, Onishi Y, Katsu Y, Miyagawa S, Ogino Y, Yatsu R, Kohno S, Takase M, Kawashima Y, Ohta Y, Aoki Y, Guillette LJ Jr, Iguchi T.
Title Establishment of transactivation assay systems using fish, amphibian, reptilian and human thyroid hormone receptors.
Journal J Appl Toxicol
Abstract Thyroid hormones are essential for the regulation of a wide range of biological processes associated with normal development and metabolism in vertebrates. For the screening of chemicals with a potential thyroid hormone and anti-thyroid hormone activities, we have established transient transactivation assay systems using thyroid hormone receptors (TRα and TRβ) from three frog species (Xenopus laevis, Silurana tropicalis and Rana rugosa), a fish (Oryzias latipes), an alligator (Alligator mississippiensis) and a human (Homo sapiens). In all species examined, similar transcriptional activities were found for triiodothyronine (T3 : 10(-11) M in TRα and 10(-10) M in TRβ) and thyroxine (T4 : 10(-9) M in TRα and 10(-8) M in TRβ). Analogs of thyroid hormone (3,5,3',-triiodothyroacetic acid and 3,3',5,5'-tetraiodothyroacetic acid) exhibited weaker activity, requiring 10-fold higher concentrations for induction of activity when compared with T3 and T4 . These results provide support for the usefulness of in vitro screening assay systems as part of an approach to test chemicals for potential thyroid hormone receptor activity. In addition, we observed that T3 -stimulated transcriptional activity of the O. latipes TRα was inhibited by 10(-5) M tetrabromobisphenol A (TBBPA). In contrast, TR antagonist activities on TRα were not encountered in other species, even with TBBPA concentrations at 10(-5) M. In vitro transactivation assay systems using TRs from various species can be used for the screening of chemicals with thyroid-receptor agonist and antagonist activities. They also can be used for studies that examine evolutionary differences among species in the potency of TR activation.
Volume 33(9)
Pages 991-1000
Published 2013-9-1
DOI 10.1002/jat.2825
PMID 23112079
MeSH Alligators and Crocodiles / metabolism Animals HEK293 Cells Humans Oryzias / metabolism Phylogeny Polybrominated Biphenyls / toxicity Ranidae / metabolism Thyroid Hormone Receptors alpha / metabolism* Thyroid Hormone Receptors beta / metabolism* Thyroxine / metabolism Transcription, Genetic Transcriptional Activation* Triiodothyronine / analogs & derivatives Triiodothyronine / metabolism Xenopus laevis / metabolism
IF 2.997
Times Cited 11
Xenopus tropicalis Nigerian H line