维生素E:不仅仅是一个单一的立体同位素
M Eggersdorfer1, K Schmidt2, S Péter3
1Department of Internal Medicine, University Medical Center Groningen, Groningen, the Netherlands.
Free radical biology & medicine
|February 24, 2024
概括
维生素E 维生素E 是一种维生素.
科学领域:
- 生物化学 生物化学
- 人体生理学 人体生理学
- 营养科学 营养科学
背景情况:
- 维生素E的定义是有争议的,有些人认为只有RRR-α-托科菲罗尔具有生理活性.
- 维生素E 缺乏症的性衰竭 (AVED) 是一种与维生素E 缺乏症相关的疾病,历史上用RRR-α-托科菲罗尔治疗.
研究的目的:
- 调查维生素E的生理定义.
- 为了评估不同维生素E形式的疗效和安全性,除了RRR-α-托科菲罗.
主要方法:
- 审查有关维生素E生物活动和机制的现有文献.
- 对α-托哥菲醇转移蛋白 (α-TTP) 与各种立体异构体的结合亲和力的分析.
- 检查关于使用不同形式的维生素E治疗AVED的临床数据.
主要成果:
- 证实,维生素E的生理活性仅限于特定的α-托哥菲罗尔形式.
- 所有α-托科菲罗尔的2R立体异构体,而不仅仅是RRR-α-托科菲罗尔,都有效地与α-TTP结合.
- 2R-形式被保留在人体血和组织中,与快速分泌的2S-立体异构体不同.
- AVED已经成功地用RRR-α-托科菲罗尔以外的维生素E形式治疗.
- 没有安全问题与维生素E的更广泛定义有关.
结论:
- 维生素E的生理学定义应该包括α-托科菲罗的所有2R-立体异构体,而不仅仅是RRR-α-托科菲罗.
- 维生素E的更广泛的定义得到了科学和监管方面的认可.
- 目前的证据支持这种包容性定义的安全性和有效性,用于治疗维生素E缺乏症.
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