Chen Qin, Huang Xiaoyan, Li Renjie
Department of Geriatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and TechnologyWuhan 430030, People's Republic of China.
Department of Emergency Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and TechnologyWuhan 430030, People's Republic of China.
Am J Transl Res. 2018 Feb 15;10(2):563-572. eCollection 2018.
Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), as a long chain non-coding RNA (lncRNA), has been reported to be upregulated in Parkinson's disease (PD). However, the mechanisms underlying this process remain unknown. Hence, to investigate the role of MALAT1 in PD, N-methyl-4-phenylpyridinium (MPP) was used to induce PD in the MN9D dopaminergic neuronal cell line and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) was used to induce PD in C57BL/6 mice. Quantitative Real-Time PCR (qRT-PCR) and western blot assay showed that the expression levels of MALAT1 and leucine-rich repeat kinase (LRRK2) were increased, and that of miR-205-5p was decreased in the midbrains of mice in which PD was induced by MPTP. MALAT1 suppressed the expression of miR-205-5p in MN9D cells. The results of luciferase reporter assay indicated that LRRK2 was a direct target of miR-205-5p. Transfection with the miR-205-5p mimics decreased, whereas transfection with miR-205-5p inhibitor increased the expression levels of LRRK2 mRNA and protein. The cell counting kit-8 (CCK-8) and flow cytometry assays showed that overexpression of LRRK2 reduced the viability and promoted apoptosis in MN9D cells treated with MPP. MALAT1 knockdown exerted a protective effect on the viability and apoptosis of MN9D cells treated with MPP, which was abrogated by LRRK2 overexpression and miR-205-5p inhibition. Our study demonstrates that the MALAT1/miR-205-5p axis regulates MPP-induced apoptosis in MN9D cells by targeting LRRK2, thereby improving our understanding of the molecular pathogenesis of PD.
转移相关的肺腺癌转录本1（MALAT1）作为一种长链非编码RNA（lncRNA），据报道在帕金森病（PD）中表达上调。然而，这一过程背后的机制仍不清楚。因此，为了研究MALAT1在PD中的作用，使用N-甲基-4-苯基吡啶鎓（MPP）在MN9D多巴胺能神经元细胞系中诱导PD，并使用1-甲基-4-苯基-1,2,3,6-四氢吡啶（MPTP）在C57BL/6小鼠中诱导PD。定量实时聚合酶链反应（qRT-PCR）和蛋白质印迹分析表明，在经MPTP诱导PD的小鼠中脑内，MALAT1和富含亮氨酸重复激酶（LRRK2）的表达水平升高，而miR-205-5p的表达水平降低。MALAT1抑制MN9D细胞中miR-205-5p的表达。荧光素酶报告基因检测结果表明，LRRK2是miR-205-5p的直接靶点。转染miR-205-5p模拟物可降低LRRK2 mRNA和蛋白的表达水平，而转染miR-205-5p抑制剂则可增加其表达水平。细胞计数试剂盒-8（CCK-8）和流式细胞术检测表明，LRRK2的过表达降低了用MPP处理的MN9D细胞的活力并促进了细胞凋亡。敲低MALAT1对用MPP处理的MN9D细胞的活力和凋亡具有保护作用，而LRRK2的过表达和miR-205-5p的抑制可消除这种保护作用。我们的研究表明，MALAT1/miR-205-5p轴通过靶向LRRK2调节MPP诱导的MN9D细胞凋亡，从而增进了我们对PD分子发病机制的理解。
