甲基组在叶酸和胆路径之间的穿
1Human Nutrition and Health, Balchem Corporation, 5 Paragon Drive, Montvale, NJ 07645, USA.
Nutrients
|August 14, 2025
概括
基本营养素叶酸和胆对于甲基平衡至关重要. 胆,特别是通过贝他因,在单碳代谢中起着关键作用,影响同型半氨酸水平.
科学领域:
- 生物化学 生物化学
- 营养科学 营养科学
- 代谢途径 代谢途径
背景情况:
- 甲基组是通过单碳 (C1-) 代谢从饮食或内源性生产中获取的,形成S-adenosylmethionine (SAM).
- 叶酸和胆 (通过贝他因) 是C1代谢中密切相关的必需营养素.
- 胆或叶酸的缺陷会破坏肝脏叶酸,SAM水平和血同类,影响甲基平衡.
研究的目的:
- 审查一碳代谢中叶酸和胆之间的代谢相互作用.
- 突出胆在维持甲基平衡和SAM生产中的重要作用.
- 讨论叶酸和胆对同型半氨酸水平和甲基化状态的影响.
主要方法:
- 对大鼠甲基供体缺乏饮食的实验研究的综述.
- 分析胆,贝他因和叶酸补充剂对代谢标记物的影响.
- 在禁食和甲氨酸后负载条件下检测血类型半氨酸水平.
主要成果:
- 胆缺乏症显著降低肝脏叶酸,肝脏SAM,并增加血类固醇.
- 叶酸缺乏导致肝脏胆的减少.
- 贝他因补充剂可以恢复血中的贝他因和叶酸水平.
- 叶酸状况主要影响禁食类固醇,而胆/β类固醇通过BHMT途径显著影响后甲氨酸负载类固醇.
结论:
- 足够的叶酸和胆 (或贝他因) 摄入对于维持身体的甲基平衡至关重要.
- 胆是C1代谢的重要参与者,通过BHMT途径对SAM的产生作出重大贡献.
- 与禁食水平相比,评估后 metionin 负载的同型半氨酸更好地反映了胆对细胞甲基化贡献.
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