Terao Junji
Institute of Health Biosciences, University of Tokushima Graduate School, Tokushima, 770-8503, Japan,
Subcell Biochem. 2014;77:83-91. doi: 10.1007/978-94-007-7920-4_7.
Cholesterol is one of the oxidizable lipids constituting biomembranes and plasma lipoproteins. Cholesterol hydroperoxides (Chol-OOH) are the primary products if cholesterol is subjected to attack by reactive oxygen species. In particular, singlet molecular oxygen reacts with cholesterol to yield cholesterol 5α-hydroperoxide as the major hydroperoxide species. Chol-OOH may accumulate in biological systems because of its resistance to glutathione-dependent enzymatic detoxification reactions. Their degradation products (including hydroxycholesterol and 7-ketocholesterol) participate in the pathophysiological functions of oxysterols. Highly reactive cholesterol 5,6-secosterol present in atherosclerotic lesions can be derived from the degradation of cholesterol 5α-hydroperoxide. Chol-OOH themselves may affect the lipid rafts of biomembranes, thereby leading to the modification of signal transduction pathways.
胆固醇是构成生物膜和血浆脂蛋白的可氧化脂质之一。如果胆固醇受到活性氧的攻击，胆固醇氢过氧化物（Chol-OOH）是主要产物。特别是，单线态分子氧与胆固醇反应生成胆固醇5α-氢过氧化物作为主要的氢过氧化物种类。Chol-OOH可能因其对谷胱甘肽依赖性酶解毒反应的抗性而在生物系统中积累。它们的降解产物（包括羟基胆固醇和7-酮胆固醇）参与氧化甾醇的病理生理功能。存在于动脉粥样硬化病变中的高反应性胆固醇5,6-断胆甾醇可源自胆固醇5α-氢过氧化物的降解。Chol-OOH本身可能会影响生物膜的脂筏，从而导致信号转导途径的改变。
