Alzheimer’s disease (AD) is a chronic neurodegenerative disease in the central nervous system that has complex pathogenesis in the elderly. The current review focuses on the epigenetic mechanisms of AD, according to the latest findings. One of the best-characterized chromatin modifications in epigenetic mechanisms is DNA methylation. Highly replicable data shows that AD occurrence is often accompanied by methylation level changes of the AD-related gene. Homocysteine (Hcy) is not only an intermediate product of one-carbon metabolism but also an important independent risk factor of AD; it can affect the cognitive function of the brain by changing the one-carbon metabolism and interfering with the DNA methylation process, resulting in cerebrovascular disease. In general, Hcy may be an environmental factor that affects AD via the DNA methylation pathway with a series of changes in AD-related substance. This review will concentrate on the relation between DNA methylation and Hcy and try to figure out their rule in the pathophysiology of AD.

中文翻译：

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同型半胱氨酸代谢异常：从 DNA 甲基化洞察阿尔茨海默病。


阿尔茨海默病（AD）是一种中枢神经系统慢性神经退行性疾病，在老年人中发病机制复杂。根据最新发现，当前的综述重点关注 AD 的表观遗传机制。表观遗传机制中最典型的染色质修饰之一是 DNA 甲基化。高度可重复的数据表明，AD的发生往往伴随着AD相关基因甲基化水平的变化。同型半胱氨酸（Hcy）不仅是一碳代谢的中间产物，也是AD的重要独立危险因素；它可以通过改变一碳代谢、干扰DNA甲基化过程，影响大脑的认知功能，导致脑血管疾病。总的来说，Hcy可能是通过DNA甲基化途径影响AD的环境因素，引起AD相关物质的一系列变化。本文将重点探讨DNA甲基化与Hcy之间的关系，并试图探讨其在AD病理生理学中的规律。