有关不良结果途径的综合测试,以识别通过氧化DNA损伤引起基因毒性的化学物质:对4-尼托基诺林-1-氧化物的案例研究
Elizabeth Huliganga1,2, Eunnara Cho2, Carol D Swartz3
1Department of Biology, University of Ottawa, Ottawa, Canada.
Environmental and molecular mutagenesis
|May 9, 2025
概括
这项研究表明,在人类细胞中使用4-尼托基诺林-1-氧化物 (4NQO) 的不良结果途径 (AOP) 告知测试策略. 综合方法成功量化化学诱导的DNA损伤,突变和染色体异常随着时间的推移.
科学领域:
- 毒理学和分子生物学
- 基因毒性和风险评估
- 负面结果路径 (AOPs)
背景情况:
- 负面结果途径 (AOP) 为理解化学毒性和解释新测试方法数据提供了一个框架.
- AOP #296将氧化DNA损伤与突变和染色体异常联系起来,这对于监管决策至关重要.
- 通过已建立的AOP来评估化学品可以提高风险评估的可靠性.
研究的目的:
- 开发和验证一个综合测试策略,根据AOP #296.6的信息.
- 通过基于AOP的方法评估4-尼托基诺-1-氧化物 (4NQO) 的基因毒性潜力.
- 量化描述4NQO对DNA损伤和突变的时间和度相关影响.
主要方法:
- 人类TK6细胞在一个时间序列实验中暴露于4NQO.
- 氧化性DNA损伤和链断裂使用CometChip测定与没有formamidopyrimidine DNA glycosylase (Fpg) 测量.
- 微核 (MN) 频率通过流动细胞计分析,并使用双重测序 (DS) 评估突变.
主要成果:
- 4NQO诱导的氧化DNA损伤,链断裂,MN频率和突变频率的度和时间依赖性增加.
- 氧化性DNA损伤是早期检测到的,而突变出现在较晚的时间点 (48小时).
- 双重测序确定了与氧化DNA病变相一致的C > A转变,并揭示了氧化损伤的修复与持久的链断裂.
结论:
- 该研究提供了一种经过验证的AOP-informed测试策略,用于通过AOP #296.6评估化学品.
- 综合方法有效量化4NQO诱导的基因毒性,并阐明路径的动态.
- 双重测序被证实是AOP框架内对突变性评估的有价值工具.
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