miR-340 通过靶向 BACE1（β-淀粉样前体蛋白裂解酶 1）减少阿尔茨海默病中淀粉样β的积累。

MiR-340 Reduces the Accumulation of Amyloid-β Through Targeting BACE1 (β-site Amyloid Precursor Protein Cleaving Enzyme 1) in Alzheimer's Disease.

机构信息

Department of Neurology, Jingzhou First People's Hospital, The First Affiliated Hospital of Yangtze University, Jingzhou City, Hubei Province, 434000, China.

出版信息

Curr Neurovasc Res. 2020;17(1):86-92. doi: 10.2174/1567202617666200117103931.

DOI:10.2174/1567202617666200117103931

PMID:31957613

Abstract

BACKGROUND

Alzheimer's disease (AD) is the most common neurodegenerative disease, and the accumulation of amyloid-β is the initial process in AD. MicroRNAs (miRNAs) are widely known as key regulators of the accumulation of amyloid-β in AD. This study analyzed the potential effects and possible internal mechanisms of miR-340 on AD.

METHODS

The expression of miR-340 in senescence-accelerated mouse prone-8 (SAMP8) mouse and senescence-accelerated mice/resistant-1 (SAMR1) mouse was evaluated by qRT-PCR (quantitative real-time polymerase chain reaction). The expression of β-site amyloid precursor protein cleaving enzyme 1 (BACE1) was determined by qRT-PCR and western blot. The binding ability between miR-340 and BACE1 was verified by dual-luciferase reporter assay. In vitro cell model of AD was established in human neuroblastoma SH-SY5Y cells transfected with Swedish mutant form of amyloid precursor protein (APPswe). The effect of miR-340 on the accumulation of amyloid- β was investigated by western blot analysis. Flow cytometry was conducted to detect cell apoptosis.

RESULTS

MiR-340 was down-regulated in the hippocampus of AD model SAMP8 mouse compared to SAMR1 mouse, while BACE1 was up-regulated in SAMP8, suggesting a negative correlation between miR-340 and BACE1 in SAMP8 mouse. MiR-340 could directly bind with BACE1, and over-expression of miR-340 decreased expression of BACE1 in SH-SY5Y/APPswe cells. MiR- 340 reduced the accumulation of amyloid-β and suppressed cell apoptosis through targeting BACE1 in SH-SY5Y/APPswe cells.

CONCLUSION

MiR-340 was downregulated in AD and reduced the accumulation of amyloid-β through targeting BACE1, suggesting a potential therapeutic target for AD.

摘要

背景

阿尔茨海默病（AD）是最常见的神经退行性疾病，淀粉样β的积累是 AD 的初始过程。 microRNAs（miRNAs）被广泛认为是 AD 中淀粉样β积累的关键调节因子。本研究分析了 miR-340 对 AD 的潜在影响和可能的内在机制。

方法

通过 qRT-PCR（实时定量聚合酶链反应）评估 miR-340 在快速老化小鼠品系 8（SAMP8）和快速老化小鼠/抗性 1（SAMR1）小鼠中的表达。通过 qRT-PCR 和 Western blot 测定 β-位点淀粉样前体蛋白裂解酶 1（BACE1）的表达。通过双荧光素酶报告基因实验验证 miR-340 与 BACE1 的结合能力。通过转染瑞典突变型淀粉样前体蛋白（APPswe）的人神经母细胞瘤 SH-SY5Y 细胞建立 AD 的体外细胞模型。通过 Western blot 分析研究 miR-340 对淀粉样β积累的影响。通过流式细胞术检测细胞凋亡。

结果

与 SAMR1 小鼠相比，AD 模型 SAMP8 小鼠海马中的 miR-340 下调，而 BACE1 上调，提示 SAMP8 小鼠中 miR-340 与 BACE1 呈负相关。miR-340 可直接与 BACE1 结合，过表达 miR-340 可降低 SH-SY5Y/APPswe 细胞中 BACE1 的表达。miR-340 通过靶向 BACE1 减少 SH-SY5Y/APPswe 细胞中淀粉样β的积累并抑制细胞凋亡。