Department of Geriatrics, Yantai Affiliated Hospital of Binzhou Medical University, Yantai, Shandong, China.
Department of Pharmacy, The Affiliated Yantai Yuhuangding Hospital of Qingdao University, Yantai, Shandong, China.
Neurochem Res. 2021 Mar;46(3):675-685. doi: 10.1007/s11064-021-03240-1. Epub 2021 Jan 20.
Alzheimer's disease (AD) is a neurodegenerative disorder disease, disturbing people's normal life. Syringin was mentioned to antagonize Amyloid-β (Aβ)-induced neurotoxicity. However, the action mechanism is still not fully elucidated. This study aimed to explore a molecular mechanism of syringin in defending Aβ-induced neurotoxicity. SK-N-SH and SK-N-BE cells were treated with amyloid β-protein fragment 25-35 (Aβ) to induce cell neurotoxicity. The injury effects were distinguished by assessing cell viability and cell apoptosis using cell counting kit-8 (CCK-8) assay and flow cytometry assay, respectively. The expression of Cleaved-caspase3 (Cleaved-casp3), B cell lymphoma/leukemia-2 (Bcl-2), Bcl-2 associated X protein (Bax) and BH3 interacting domain death agonist (BID) at the protein level was determined by western blot. The expression of miR-124-3p and BID was detected using quantitative real-time polymerase chain reaction (qRT-PCR). The interaction between miR-124-3p and BID was predicted by the online database starBase and confirmed by dual-luciferase reporter assay plus RNA pull-down assay. Aβ treatment inhibited cell viability and induced cell apoptosis, while the addition of syringin recovered cell viability and suppressed cell apoptosis. MiR-124-3p was significantly downregulated in Aβ-treated SK-N-SH and SK-N-BE cells, and BID was upregulated. Nevertheless, the addition of syringin reversed their expression. BID was a target of miR-124-3p, and its downregulation partly prevented Aβ-induced injuries. Syringin protected against Aβ-induced neurotoxicity by enhancing miR-124-3p expression and weakening BID expression, and syringin strengthened the expression of miR-124-3p to diminish BID level. Syringin ameliorated Aβ-induced neurotoxicity in SK-N-SH and SK-N-BE cells by regulating miR-124-3p/BID pathway, which could be a novel theoretical basis for syringin to treat AD.
阿尔茨海默病（AD）是一种神经退行性疾病，扰乱人们的正常生活。丁香苷被提到可拮抗淀粉样β（Aβ）诱导的神经毒性。然而，其作用机制尚不完全清楚。本研究旨在探讨丁香苷在防御 Aβ 诱导的神经毒性中的分子机制。用淀粉样β蛋白片段 25-35（Aβ）处理 SK-N-SH 和 SK-N-BE 细胞，以诱导细胞神经毒性。通过细胞计数试剂盒-8（CCK-8）测定和流式细胞术分别评估细胞活力和细胞凋亡，以区分损伤作用。用蛋白质印迹法测定Cleaved-caspase3（Cleaved-caspase3）、B 细胞淋巴瘤/白血病-2（Bcl-2）、Bcl-2 相关 X 蛋白（Bax）和 BH3 相互作用域死亡激动剂（BID）的蛋白表达水平。用实时定量聚合酶链反应（qRT-PCR）检测 miR-124-3p 和 BID 的表达。通过在线数据库 starBase 预测 miR-124-3p 和 BID 之间的相互作用，并通过双荧光素酶报告基因测定和 RNA 下拉测定进行验证。Aβ 处理抑制细胞活力并诱导细胞凋亡，而丁香苷的添加恢复了细胞活力并抑制了细胞凋亡。miR-124-3p 在 Aβ 处理的 SK-N-SH 和 SK-N-BE 细胞中显著下调，BID 上调。然而，添加丁香苷可逆转其表达。BID 是 miR-124-3p 的靶标，其下调部分阻止了 Aβ 诱导的损伤。丁香苷通过增强 miR-124-3p 的表达和减弱 BID 的表达来抵抗 Aβ 诱导的神经毒性，并且丁香苷增强了 miR-124-3p 的表达以降低 BID 水平。丁香苷通过调节 miR-124-3p/BID 通路改善 SK-N-SH 和 SK-N-BE 细胞中的 Aβ 诱导的神经毒性，这可能为丁香苷治疗 AD 提供新的理论依据。
