乙烯基碳化合物受体依赖的毒性需要代谢能力
Christian I Rude1, Lindsay B Wilson1, Jane La Du1
1Environmental and Molecular Toxicology Department, Oregon State University, Corvallis, OR 97333, United States.
概括
斑马鱼中的雷丁毒性是由其代谢物中介的,而不是母化合物,突出了生物转化在多环芳 (PAH) 发育毒性的作用. 这项研究揭示了细胞染色体P450 1A (CYP1A) 对视网膜诱导的毒性至关重要.
科学领域:
- 环境毒理学环境毒理学
- 发展生物学 发展生物学
- 代谢学 代谢学 代谢学
背景情况:
- 多环芳 (PAH) 是具有多种毒性的环境污染物,通常通过基碳化合物受体 (AHR) 激活.
- 雷是一种特定的PAH,在斑马鱼中引起了Ahr2-依赖的产性,但没有观察到直接的AHR激活,这表明代谢物有作用.
- 了解影响PAH毒性的代谢途径和遗传因素对于风险评估至关重要.
研究的目的:
- 调查新陈代谢的作用,特别是细胞P450酶 (CYPs) 和微生物群,在斑马鱼的视网膜诱导的发育毒性.
- 为了确定斑马鱼胚胎中雷丁的临界暴露窗口和药理动力学特征.
- 阐明雷或其代谢物诱导毒性的机制.
主要方法:
- 通过使用CRISPR-Cas9.9生成Cyp1a-null和Cyp1b1-null斑马鱼.
- 在不同发育阶段 (受精后24-48小时) 评估了网膜毒性.
- 在斑马鱼胚胎中使用体内试验量化的网膜蛋白吸收,损失和代谢物形成.
主要成果:
- Cyp1a-null斑马鱼对网膜毒性的敏感性增加,而Cyp1b1-null鱼的敏感性较小.
- 在受精后24至48小时内暴露于雷对毒性诱导至关重要.
- 在斑马鱼胚胎中检测到保留代谢物,在毒性开始之前,表明代谢激活.
结论:
- 斑马鱼中雷诱导的发育毒性主要由其代谢产物介导,而不是母化合物.
- 细胞染色体P450 1A (CYP1A) 在网膜蛋白的代谢激活中起着重要作用,有助于其毒性.
- 这项研究强调了在PAHs的机械和预测毒理学研究中考虑生物转化的重要性.
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