In order to investigate the effects of metallic nanoparticles (NPs) on the performance of in vitro bioassay, zinc oxide NP (ZnO NP), aluminum oxide NP (Al₂O₃ NP), bare silver NP (Ag NP), and Ag NP capped with citrate (Ag^cit NP) were evaluated with yeast (Saccharomyces cerevisiae Y190) two-hybrid system (YES assay), carrying Japanese medaka estrogen receptors (mERs) in the presence of 17β-estradiol (E2, 10⁻⁶ M), a reference chemical for estrogenic activity. The distribution of NPs in the yeast was also examined by field-emission transmission electron microscopy (FE-TEM). The results show that TEM analysis revealed that NPs were present inside the yeast and accumulated deep inside the cell organelles, suggesting that cell death was caused by NPs. However, despite no significant change of mortality, the E2 estrogenic activities in yeast exposed to ZnO NP and Al₂O₃ NP were dose-dependently reduced. For Ag NP and Ag^cit NP, such phenomenon observed in the exposure of ZnO NP and Al₂O₃ NP did not occur. From the observations, we found that ZnO NP and Al₂O₃ NP in the environmental media could result in underestimated estrogenicity of endocrine-disrupting compounds when evaluated by YES assay.

中文翻译：

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暴露于非致命水平的金属纳米颗粒抑制酵母筛选试验的雌激素反应。

为了研究金属纳米颗粒（NPs）对体外生物测定性能的影响，使用氧化锌NP（ZnO NP），氧化铝NP（Al ₂ O ₃ NP），裸银NP（Ag NP）和Ag NP用柠檬酸（AG封端^CIT NP）与酵母（评价酿酒酵母Y190）双杂交系统（YES测定），在17β雌二醇的存在下实施雌激素受体（MERS）日本青鳉（E2，10 ^-6M），雌激素活性的参考化学品。还通过场发射透射电子显微镜（FE-TEM）检查了酵母中NPs的分布。结果表明，TEM分析表明，NPs存在于酵母中，并在细胞器内部深入积累，表明细胞死亡是由NPs引起的。然而，尽管死亡率没有显着变化，但是暴露于ZnO NP和Al ₂ O ₃ NP的酵母中的E2雌激素活性却呈剂量依赖性降低。对于Ag NP和Ag ^cit NP，在ZnO NP和Al ₂ O ₃ NP的暴露中未观察到这种现象。通过观察，我们发现ZnO NP和Al ₂ O ₃ 通过YES分析评估时，环境介质中的NP可能导致低估内分泌干扰物的雌激素性。