Department of Pharmacy, University of Pisa, Via Bonanno 6, 56126 Pisa, Italy.
NEST, Istituto di Nanoscienze, Consiglio Nazionale delle Ricerche, Scuola Normale Superiore, Piazza San Silvestro 12, 56127 Pisa, Italy.
Oxid Med Cell Longev. 2021 Jan 2;2021:8869849. doi: 10.1155/2021/8869849. eCollection 2021.
Alzheimer's disease (AD) is characterized by proteasome activity impairment, oxidative stress, and epigenetic changes, resulting in -amyloid (A) production/degradation imbalance. Apolipoprotein E (ApoE) is implicated in A clearance, and particularly, the ApoE 4 isoform predisposes to AD development. Regular physical activity is known to reduce AD progression. However, the impact of ApoE polymorphism and physical exercise on A production and proteasome system activity has never been investigated in human peripheral blood cells, particularly in erythrocytes, an emerging peripheral model used to study biochemical alteration. Therefore, the influence of ApoE polymorphism on the antioxidant defences, amyloid accumulation, and proteasome activity was here evaluated in human peripheral blood cells depending on physical activity, to assess putative peripheral biomarkers for AD and candidate targets that could be modulated by lifestyle. Healthy subjects were enrolled and classified based on the ApoE polymorphism (by the restriction fragment length polymorphism technique) and physical activity level (Borg scale) and grouped into ApoE 4/non-4 carriers and active/non-active subjects. The plasma antioxidant capability (AOC), the erythrocyte A production/accumulation, and the nuclear factor erythroid 2-related factor 2 (Nrf2) mediated proteasome functionality were evaluated in all groups by the chromatographic and immunoenzymatic assay, respectively. Moreover, epigenetic mechanisms were investigated considering the expression of histone deacetylase 6, employing a competitive ELISA, and the modulation of two key miRNAs (miR-153-3p and miR-195-5p), through the miRNeasy Serum/Plasma Mini Kit. ApoE 4 subjects showed a reduction in plasma AOC and an increase in the Nrf2 blocker, miR-153-3p, contributing to an enhancement of the erythrocyte concentration of A. Physical exercise increased plasma AOC and reduced the amount of A and its precursor, involving a reduced miR-153-3p expression and a miR-195-5p enhancement. Our data highlight the impact of the ApoE genotype on the amyloidogenic pathway and the proteasome system, suggesting the positive impact of physical exercise, also through epigenetic mechanisms.
阿尔茨海默病（AD）的特征是蛋白酶体活性受损、氧化应激和表观遗传改变，导致β淀粉样蛋白（A）的产生/降解失衡。载脂蛋白 E（ApoE）参与 A 的清除，特别是 ApoE4 同工型易患 AD 发展。有规律的体育锻炼已知可减缓 AD 的进展。然而，ApoE 多态性和体育锻炼对人外周血红细胞中 A 的产生和蛋白酶体系统活性的影响从未被研究过，红细胞是一种新兴的外周模型，用于研究生化改变。因此，在这里根据身体活动评估了 ApoE 多态性对人外周血细胞中抗氧化防御、淀粉样蛋白积累和蛋白酶体活性的影响，以评估 AD 的潜在外周生物标志物和可能通过生活方式调节的候选靶点。根据 ApoE 多态性（通过限制性片段长度多态性技术）和身体活动水平（Borg 量表）招募并分类健康受试者，并将其分为 ApoE4/非 4 携带者和活跃/非活跃受试者。通过色谱和免疫酶测定分别评估所有组的血浆抗氧化能力（AOC）、红细胞 A 的产生/积累和核因子红细胞 2 相关因子 2（Nrf2）介导的蛋白酶体功能。此外，通过竞争性 ELISA 研究了组蛋白去乙酰化酶 6 的表达，通过 miRNeasy 血清/血浆 Mini Kit 研究了两个关键 miRNA（miR-153-3p 和 miR-195-5p）的调节，考虑了表观遗传机制。ApoE4 受试者的血浆 AOC 降低，Nrf2 阻滞剂 miR-153-3p 增加，导致红细胞 A 浓度增加。体育锻炼增加了血浆 AOC，减少了 A 和其前体的量，涉及 miR-153-3p 表达减少和 miR-195-5p 增强。我们的数据强调了 ApoE 基因型对淀粉样蛋白途径和蛋白酶体系统的影响，表明体育锻炼的积极影响，也通过表观遗传机制。
