通过IDH1减少谷氨胺代谢,在缺氧下调解脂质生成
Christian M Metallo1, Paulo A Gameiro, Eric L Bell
1Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Nature
|November 22, 2011
概括
人类细胞通过α-谷氨酸的还原代谢产生乙-CoA (AcCoA) 用于脂质合成. 缺氧状况和VHL缺乏细胞严重依赖这种谷氨酸衍生途径进行新型脂质生成.
科学领域:
- 细胞代谢的细胞代谢.
- 生物化学 生物化学
- 癌症生物学 癌症生物学
背景情况:
- 乙-CoA (AcCoA) 对于脂肪酸合成和蛋白质乙化至关重要.
- 传统的从葡萄糖生成AcCoA在低毒性或高甘油性细胞中受损.
- 谷氨胺代谢在低氧细胞中的作用尚不清楚.
研究的目的:
- 研究哺乳动物细胞中其他AcCoA合成途径,特别是在低氧状态下.
- 阐明谷氨胺代谢在支持特定细胞条件下的脂质生成中的作用.
主要方法:
- 在不同氧气条件下利用人类细胞系 (正常氧和缺氧).
- 通过还原性炭化途径研究的代谢流量.
- 评估了异酸盐脱酶-1 (IDH1) 活性的影响.
- 检查了脂质合成速率和对谷氨胺的依赖.
主要成果:
- 通过α-谷氨酸的还原代谢确定了依赖于异酸脱酶-1 (IDH1) 的途径,用于通过α-谷氨酸的还原代谢来合成AcCoA.
- 缺氧细胞主要使用由谷氨胺衍生的α-谷氨酸的降低性碳氧化,以进行新型脂质生成.
- 在VON Hippel-Lindau (VHL) 瘤抑制剂缺乏的细胞系中,即使在正常的氧气水平下,也表现出降解性谷氨胺代谢对脂质合成的偏好.
结论:
- 氧气水平关键调节碳流向AcCoA生产和脂质合成.
- 减少性谷氨胺代谢是AcCoA生成和低氧和VHL缺乏细胞中的脂质生成的关键途径.
- 这一途径突出显示了细胞代谢对氧气供应和瘤信号的显著适应.
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