Institute of Environmental Ecology, IDEA Consultants, Inc., Yaizu, Japan.
Department of Science and Technology for Biological Resources and Environment, Graduate School of Agriculture, Ehime University, Matsuyama, Japan.
J Appl Toxicol. 2021 Aug;41(8):1200-1221. doi: 10.1002/jat.4104. Epub 2021 Jan 24.
Under the Organisation for Economic Co-operation and Development (OECD), the Ministry of the Environment of Japan (MOE) added Japanese medaka (Oryzias latipes) to the test guideline fish short-term reproduction assay (FSTRA) developed by the United States Environmental Protection Agency (US EPA) using fathead minnow (Pimephales promelas). The FSTRA was designed to detect endocrine disrupting effects of chemicals interacting with the hypothalamic-pituitary-gonadal axis (HPG axis) such as agonists or antagonists on the estrogen receptor (Esr) and/or the androgen receptor (AR) and steroidogenesis inhibitors. We conducted the FSTRA with Japanese medaka, in accordance with OECD test guideline number 229 (TG229), for 16 chemicals including four Esr agonists, two Esr antagonists, three AR agonists, two AR antagonists, two steroidogenesis inhibitors, two progesterone receptor agonists, and a negative substance, and evaluated the usability and the validity of the FSTRA (TG229) protocol. In addition, in vitro reporter gene assays (RGAs) using Esr1 and ARβ of Japanese medaka were performed for the 16 chemicals, to support the interpretation of the in vivo effects observed in the FSTRA. In the present study, all the test chemicals, except an antiandrogenic chemical and a weak Esr agonist, significantly reduced the reproductive status of the test fish, that is, fecundity or fertility, at concentrations where no overt toxicity was observed. Moreover, vitellogenin (VTG) induction in males and formation of secondary sex characteristics (SSC), papillary processes on the anal fin, in females was sensitive endpoints to Esr and AR agonistic effects, respectively, and might be indicators of the effect concentrations in long-term exposure. Overall, it is suggested that the in vivo FSTRA supported by in vitro RGA data can adequately detect effects on the test fish, O. latipes, and probably identify the mode of action (MOA) of the chemicals tested.
在经济合作与发展组织（OECD）的框架下，日本环境省（MOE）采用美国环保署（US EPA）开发的使用黑头呆鱼（Pimephales promelas）的测试指南鱼类短期繁殖试验（FSTRA），将日本青鳉（Oryzias latipes）添加到该指南中。FSTRA 旨在检测与下丘脑-垂体-性腺轴（HPG 轴）相互作用的化学物质的内分泌干扰效应，例如雌激素受体（Esr）和/或雄激素受体（AR）的激动剂或拮抗剂，以及甾体生成抑制剂。我们根据 OECD 测试指南第 229 号（TG229），用日本青鳉进行了 16 种化学物质的 FSTRA，包括 4 种 Esr 激动剂、2 种 Esr 拮抗剂、3 种 AR 激动剂、2 种 AR 拮抗剂、2 种甾体生成抑制剂、2 种孕激素受体激动剂和 1 种阴性物质，并评估了 FSTRA（TG229）方案的可用性和有效性。此外，还针对 16 种化学物质进行了使用日本青鳉 Esr1 和 ARβ的体外报告基因试验（RGA），以支持对 FSTRA 中观察到的体内效应的解释。在本研究中，除了一种抗雄激素化学物质和一种弱 Esr 激动剂外，所有测试化学物质在没有明显毒性的浓度下，均显著降低了试验鱼的繁殖状况，即繁殖力或生育力。此外，雄鱼的卵黄蛋白原（VTG）诱导和雌鱼的第二性征（SSC）形成，即肛鳍上的乳头状突起，分别是 Esr 和 AR 激动效应的敏感终点，并且可能是长期暴露的效应浓度的指示物。总的来说，有证据表明，体外 RGA 数据支持的体内 FSTRA 能够充分检测对试验鱼（日本青鳉）的影响，并可能确定测试化学物质的作用模式（MOA）。
