缺氧时I复合物的活性:对代谢的影响
1Department of Biochemistry, Semmelweis University, Budapest 1094, Hungary.
Biochemical Society transactions
|March 25, 2024
概括
低毒性癌细胞利用剩余的复杂I活性来再生NAD+,为谷氨酸溶解提供能量. 这表明,复杂I抑制剂甚至在氧化酸化受损 (OXPHOS) 的情况下也可以治疗癌症.
科学领域:
- 生物化学 生物化学
- 癌症新陈代谢 癌症新陈代谢
- 在瘤学瘤学.
背景情况:
- 固体瘤通常含有缺氧区域,癌细胞无法进行氧化酸化 (OXPHOS).
- 尽管缺氧,但这些细胞保持了依赖NAD+的代谢活动.
- 剩余复合物I活动,独立于氧气,在NAD+再生中起着至关重要的作用.
研究的目的:
- 为了研究持续的复合I活动在低氧癌细胞中的作用.
- 阐明依赖NAD+的代谢途径,支持在缺氧下癌细胞存活.
- 探索针对OXPHOS缺乏癌症的复合I的治疗潜力.
主要方法:
- 在低氧条件下对生化途径和酶活动的审查.
- 分析NAD+/NADH氧化还原平衡及其对代谢流量的影响.
- 检查谷氨酸溶解和相关的代谢途径.
主要成果:
- 剩余复合物I即使没有氧气,也会将NADH氧化为NADH+.
- 再生后的NAD+在谷氨酸溶解中为α-甲酸脱酶复合体提供燃料.
- 通过 succinyl-CoA结合酶的基质水平酸化产生高能酸盐,部分补偿OXPHOS缺乏.
结论:
- 低毒性癌细胞依赖于复杂I介导的NAD+再生来维持谷氨酸分解.
- 这种代谢适应允许部分能量补偿,尽管OXPHOS受损.
- 向复合物I可能是治疗OXPHOS受损癌症的可行策略.
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