胆固醇在细胞膜中比脂类林诺酸盐更容易氧化,产生胆固醇氧化物
Yoshiro Saito1, Noriko Noguchi2, Etsuo Niki3
1Laboratory of Molecular Biology and Metabolism, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan; The Systems Life Sciences Laboratory, Department of Medical Life Systems, Faculty of Life and Medical Sciences, Doshisha University, Kyotanabe, Japan.
Free radical biology & medicine
|December 15, 2023
概括
胆固醇比以前认为的更容易在细胞膜中自氧化,这挑战了多不和脂肪酸 (PUFA) 更容易氧化的教条. 这是因为胆固醇和PUFA被分离在细胞膜内,限制了抗氧化剂的保护.
科学领域:
- 生物化学 生物化学
- 细胞生物学 细胞生物学
- 氧化压力是一种氧化压力.
背景情况:
- 胆固醇对于细胞膜和激素合成至关重要.
- 胆固醇和其氧化产物的升高是健康风险.
- 众所周知,多不和脂肪酸 (PUFA) 容易氧化.
研究的目的:
- 挑战关于胆固醇抗氧化能力的既定观点.
- 调查胆固醇和PUFAs对自身氧化的不同敏感性.
- 为了解释人类中所观察到的胆固醇和酸氧化产物的水平.
主要方法:
- 基于现有观察和化学反应原理的假设论文.
- 血中的胆固醇和PUFA氧化率与细胞膜的比较.
- 在人体样本中分析胆固醇和酸氧化产品水平.
主要成果:
- 在血中,胆固醇的氧化速度比PUFA慢.
- 与化学反应相反,胆固醇在细胞膜中的自氧化速度比烯酸更快.
- 观察到的人类氧化产品水平支持胆固醇增加的膜敏感性.
结论:
- 胆固醇在细胞膜中的自氧化比过氧基反应性预测的要快.
- 胆固醇和PUFAs的膜域分离会影响它们的氧化.
- 维生素E的分布限制了它的抗氧化作用在领域的胆固醇.
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