IRCCS Centro Neurolesi "Bonino-Pulejo", Via Provinciale Palermo, Contrada Casazza, 98124 Messina, Italy.
Int J Mol Sci. 2017 Nov 23;18(12):2504. doi: 10.3390/ijms18122504.
Alzheimer's disease (AD) is a neurodegenerative disorder representing the major cause of dementia. It is characterized by memory loss, and cognitive and behavioral decline. In particular, the hallmarks of the pathology are amyloid-β (Aβ) plaques and neurofibrillary tangles (NFTs), formed by aggregated hyperphosphorylated tau protein. Oxidative stress plays a main role in AD, and it is involved in initiation and progression of AD. It is well known that Aβ induced oxidative stress, promoting reactive oxygen species (ROS) production and consequently lipid peroxidation, protein oxidation, tau hyperphosphorylation, results in toxic effects on synapses and neurons. In turn, oxidative stress can increase Aβ production. For these reasons, the administration of an antioxidant therapy in AD patients was suggested. The term vitamin E includes different fat-soluble compounds, divided into tocopherols and tocotrienols, that possess antioxidant action. α-Tocopherol is the most studied, but some studies suggested that tocotrienols may have different health promoting capacities. In this review, we focused our attention on the effects of vitamin E supplementation in AD animal models and AD patients or older population. Experimental models showed that vitamin E supplementation, by decreasing oxidative stress, may be a good strategy to improve cognitive and memory deficits. Furthermore, the combination of vitamin E with other antioxidant or anti-inflammatory compounds may increase its efficacy. However, even if some trials have evidenced some benefits, the effects of vitamin E in AD patients are still under debate.
阿尔茨海默病（AD）是一种神经退行性疾病，是痴呆的主要病因。其特征是记忆力减退、认知和行为能力下降。特别是，淀粉样蛋白-β（Aβ）斑块和神经原纤维缠结（NFTs）是病理学的特征，由聚集的过度磷酸化 tau 蛋白形成。氧化应激在 AD 中起主要作用，参与 AD 的起始和进展。众所周知，Aβ诱导氧化应激，促进活性氧（ROS）的产生，进而导致脂质过氧化、蛋白质氧化、tau 过度磷酸化，对突触和神经元产生毒性作用。反过来，氧化应激可以增加 Aβ的产生。基于这些原因，建议在 AD 患者中进行抗氧化治疗。维生素 E 一词包括不同的脂溶性化合物，分为生育酚和三烯生育酚，具有抗氧化作用。α-生育酚是研究最多的，但一些研究表明，三烯生育酚可能具有不同的促进健康的能力。在这篇综述中，我们将注意力集中在维生素 E 补充剂在 AD 动物模型和 AD 患者或老年人群中的作用上。实验模型表明，维生素 E 补充剂通过降低氧化应激，可能是改善认知和记忆缺陷的一种很好的策略。此外，维生素 E 与其他抗氧化剂或抗炎化合物的联合使用可能会增加其疗效。然而，尽管一些试验已经证明了一些益处，但维生素 E 在 AD 患者中的效果仍存在争议。
