Alzheimer's disease (AD) is a very common cause of dementia in the elderly. It is characterized by progressive amnesia and accretions of neurofibrillary tangles (NFTs) of neurons and senile plaques in the neuropil. After aging, the inheritance of the apolipoprotein E (ApoE) epsilon 4 (ε4) allele is the greatest risk factor for late-onset AD. The ApoE protein is the translated product of the ApoE gene. This protein undergoes proteolysis, and the resulting fragments colocalize with neurofibrillary tangles and amyloid plaques, and for that matter may be involved in AD onset and/or progression. Previous studies have reported the pathogenic potential of various ApoE fragments in AD pathophysiology. However, the pathways activated by the fragments are not fully understood. In this review, ApoE fragments obtained from post-mortem brains and body fluids, cerebrospinal fluid (CSF) and plasma, are discussed. Additionally, current knowledge about the process of fragmentation is summarized. Finally, the mechanisms by which these fragments are involved in AD pathogenesis and pathophysiology are discussed.

中文翻译：

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脑载脂蛋白 E (ApoE) 的片段化及其与阿尔茨海默病的相关性。

阿尔茨海默病 (AD) 是老年人痴呆症的常见原因。它的特点是渐进性健忘症和神经元的神经原纤维缠结 (NFT) 和神经纤维网中的老年斑的增生。衰老后，载脂蛋白 E (ApoE) epsilon 4 (ε4) 等位基因的遗传是晚发性 AD 的最大风险因素。ApoE 蛋白是 ApoE 基因的翻译产物。这种蛋白质经历蛋白水解，产生的片段与神经原纤维缠结和淀粉样斑块共定位，因此可能参与 AD 的发病和/或进展。以前的研究报道了各种 ApoE 片段在 AD 病理生理学中的致病潜力。然而，由片段激活的途径尚不完全清楚。在这次审查中，讨论了从死后大脑和体液、脑脊液 (CSF) 和血浆中获得的 ApoE 片段。此外，还总结了有关碎片化过程的当前知识。最后，讨论了这些片段参与 AD 发病机制和病理生理学的机制。