潜在致命的致癌性氧化还原循环,涉及氧化 (IV) 和谷氨
Roberto Marin1, Yachna Ahuja, Rathindra N Bose
1Department of Biomedical Sciences, Ohio University, Athens, Ohio 45701, USA.
Journal of the American Chemical Society
|August 5, 2010
概括
(IV) 复合物触发了涉及谷和氧的循环氧还原过程,导致 (VI) 和 (IV) 的持续回收. 这一循环产生破坏DNA的中间体,导致致癌.
科学领域:
- 生物化学 生物化学
- 毒理学 毒理学 毒理学
- 无机化学 无机化学
背景情况:
- (VI) 是已知的致癌物质, (IV) 复合体与DNA损伤和变异性有关.
- 了解物种的氧化还原循环对于阐明引起的毒性机制至关重要.
研究的目的:
- 在中性pH下研究(IV) - 氧复合物与谷氨之间的反应机制.
- 描述在氧化还原循环中形成的中间体.
- 评估这些中间体对DNA的破坏潜力.
主要方法:
- 对水乙烯二胺二的反应动力学研究 (peroxo) (IV) 与谷.
- (V) 和 (IV) 介质的光谱表征.
- 使用单链断裂和DNA氧化试验评估DNA损伤.
主要成果:
- 观察到一个循环氧化还原过程,涉及到持续循环的Cr (IV) 和Cr (VI) 与Cr (V) 的中间体.
- 谷氨协调诱导了Cr(IV) 到Cr(VI的自氧化,然后通过Cr(V) 减少到Cr(IV).
- 描述的中间体包括单一和双重酸复合物,这些复合物诱导了DNA单链断裂和氧化.
结论:
- 反应产生了一个自我维持的氧化还原循环,由谷氨和分子氧气促进.
- 这种持续的循环产生了破坏DNA的物种,这表明了细胞环境中 (VI) 中介致癌的机制.
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