Department of Traditional Chinese Medicine, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, No. 600 Yi Shan Road, Xuhui District, Shanghai, 200233, China.
Department of Encephalopathy, Shanghai Municipal Hospital of Traditional Chinese Medicine, Shanghai City, China.
Neurochem Res. 2022 Jun;47(6):1707-1720. doi: 10.1007/s11064-022-03563-7. Epub 2022 Mar 1.
The development of Alzheimer's disease (AD) is implicated with the dysregulation of numerous circular RNAs (circRNAs). However, the function of several circRNAs remains unclear. The aim of this study was to investigate the role of circular AXL receptor tyrosine kinase (circAXL) in AD. Cell models of AD were constructed by treating SK-N-SH cells with amyloid-β (Aβ). The expression of circAXL, miR-1306-5p and phosphodiesterase 4A (PDE4A) mRNA was detected by quantitative real-time PCR (qPCR). Cell viability was checked by CCK-8 assay. The production of inflammatory factors was monitored by ELISA. Cell apoptosis was checked by flow cytometry assay. Oxidative stress was assessed by ROS level, MDA level and SOD activity using commercial kits. Endoplasmic reticulum (ER) stress was assessed by ER-related protein markers using western blotting. The relationship between miR-1306-5p and circAXL or PDE4A was validated by RIP assay and dual-luciferase reporter assay. Serum exosomes were isolated by centrifugation to assess the diagnostic value of exosomal circAXL, miR-1306-5p and PDE4A. CircAXL was overexpressed in Aβ-treated SK-N-SH cells. CircAXL knockdown alleviated Aβ-induced cell cytotoxicity, cell apoptosis, inflammation, oxidative stress and endoplasmic reticulum (ER) stress in SK-N-SH cells. MiR-1306-5p was screened as a target of circAXL, and miR-1306-5p inhibition abolished the effects of circAXL knockdown. MiR-1306-5p inhibited the expression of PDE4A, and circAXL regulated PDE4A expression by targeting miR-1306-5p. MiR-1306-5p restoration also alleviated Aβ-induced cell injuries, while PDE4A reintroduction abolished the effects of miR-1306-5p restoration. Exosomal circAXL and exosomal miR-1306-5p had diagnostic values for AD. CircAXL knockdown alleviates Aβ-induced neurotoxicity in AD pathology via repressing PDE4A by releasing miR-1306-5p.
阿尔茨海默病（AD）的发展与许多环状 RNA（circRNA）的失调有关。然而，一些 circRNA 的功能仍然不清楚。本研究旨在探讨环状 AXL 受体酪氨酸激酶（circAXL）在 AD 中的作用。通过用淀粉样β（Aβ）处理 SK-N-SH 细胞构建 AD 细胞模型。通过实时定量 PCR（qPCR）检测 circAXL、miR-1306-5p 和磷酸二酯酶 4A（PDE4A）mRNA 的表达。通过 CCK-8 测定法检查细胞活力。通过 ELISA 监测炎症因子的产生。通过流式细胞术测定法检查细胞凋亡。使用商业试剂盒通过 ROS 水平、MDA 水平和 SOD 活性评估氧化应激。通过 Western 印迹法使用 ER 相关蛋白标志物评估内质网（ER）应激。通过 RIP 测定法和双荧光素酶报告基因测定法验证 miR-1306-5p 与 circAXL 或 PDE4A 的关系。通过离心分离血清外泌体来评估外泌体 circAXL、miR-1306-5p 和 PDE4A 的诊断价值。在 Aβ 处理的 SK-N-SH 细胞中过表达 circAXL。circAXL 敲低减轻了 Aβ 诱导的 SK-N-SH 细胞的细胞毒性、细胞凋亡、炎症、氧化应激和内质网（ER）应激。筛选出 miR-1306-5p 作为 circAXL 的靶标，并且 miR-1306-5p 抑制消除了 circAXL 敲低的作用。miR-1306-5p 抑制 PDE4A 的表达，并且 circAXL 通过靶向 miR-1306-5p 调节 PDE4A 的表达。miR-1306-5p 的恢复也减轻了 Aβ 诱导的细胞损伤，而 PDE4A 的再引入消除了 miR-1306-5p 恢复的作用。外泌体 circAXL 和外泌体 miR-1306-5p 对 AD 具有诊断价值。circAXL 敲低通过释放 miR-1306-5p 抑制 PDE4A 从而减轻 AD 病理中 Aβ 诱导的神经毒性。
