Reproductive and Genetic Center of National Research Institute for Family Planning, Beijing, 100081, China.
Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 3 Nanyitiao, Zhongguancun, Beijing, 100080, China.
Stem Cell Res Ther. 2019 Dec 18;10(1):400. doi: 10.1186/s13287-019-1487-3.
Emerging evidence suggests that miR-124 performs important biological functions in neural stem cells (NSCs); it regulates NSC behavior and promotes the differentiation of NSCs into neurons, but the exact molecular mechanism remains unknown. And also, the role of miR-124 during spinal cord injury regeneration is unclear.
In order to explore the function of miR-124 in neural differentiation, the molecular markers (Tuj1, Map2, and GFAP) correlated with the differentiation of NSCs were detected by immunofluorescence staining both in cultured mouse spinal cord progenitor cells (SC-NPCs) and in spinal cord injury (SCI) animal models. The migration ability and apoptosis of cultured SC-NPCs were also evaluated by Transwell migration assay and TUNEL assay. In addition, the relative expression of lnRNA Neat1- and Wnt/β-catenin signaling-related genes were detected by quantitative real-time PCR.
In this study, we revealed that lncRNA Neat1 is involved in regulating Wnt/β-catenin signaling that is activated by miR-124 in SC-NPCs. LncRNA Neat1 was also found to play an important role in regulating neuronal differentiation, apoptosis, and migration of SC-NPCs. Furthermore, we demonstrated that overexpression of miR-124 resulted in elevated Neat1 expression, accompanied with the functional recovery of locomotion in a mouse model of spinal cord injury.
Our results confirm the therapeutic effectiveness of miR-124 on the functional recovery of injured spinal cord, supporting the rationale and feasibility of miR-124 for spinal cord injury treatment in future clinical therapy. Furthermore, we concluded that the miR-124-Neat1-Wnt/β-catenin signaling axis is involved in regulating the cell function of SC-NPCs, and this may offer novel therapeutic avenues for future treatment of SCI.
新出现的证据表明,miR-124 在神经干细胞(NSC)中发挥重要的生物学功能;它调节 NSC 行为并促进 NSC 分化为神经元,但确切的分子机制尚不清楚。此外,miR-124 在脊髓损伤再生中的作用尚不清楚。
为了探索 miR-124 在神经分化中的功能,通过免疫荧光染色检测与 NSCs 分化相关的分子标记物(Tuj1、Map2 和 GFAP),分别在培养的小鼠脊髓祖细胞(SC-NPCs)和脊髓损伤(SCI)动物模型中进行。通过 Transwell 迁移实验和 TUNEL 实验评估培养的 SC-NPCs 的迁移能力和凋亡情况。此外,通过定量实时 PCR 检测 lncRNA Neat1 和 Wnt/β-catenin 信号相关基因的相对表达。
在这项研究中,我们揭示了 lncRNA Neat1 参与调节 Wnt/β-catenin 信号,而 miR-124 可激活该信号在 SC-NPCs 中的作用。还发现 lncRNA Neat1 在调节 SC-NPCs 的神经元分化、凋亡和迁移中起着重要作用。此外,我们证明过表达 miR-124 导致 Neat1 表达升高,并伴有脊髓损伤小鼠模型运动功能的恢复。
我们的研究结果证实了 miR-124 对损伤脊髓功能恢复的治疗效果,为未来临床治疗中 miR-124 治疗脊髓损伤提供了理论依据和可行性。此外,我们得出结论,miR-124-Neat1-Wnt/β-catenin 信号轴参与调节 SC-NPCs 的细胞功能,这可能为未来 SCI 的治疗提供新的治疗途径。