miR-144-3p对大鼠脊髓损伤后巨噬细胞炎症反应和功能恢复的影响

Effect of miR-144-3p on the inflammatory response of macrophages and functional recovery after spinal cord injury in rats

目的 探究miR-144-3p对脊髓损伤大鼠的巨噬细胞炎症反应和运动功能恢复的影响。方法 分析脊髓损伤大鼠miRNA表达数据集GSE19890中miR-144的表达情况;在ENCORI网站中预测miR-144-3p的靶基因,并通过双荧光素酶报告基因实验验证miR-144-3p与靶基因的结合情况;构建脊髓损伤大鼠模型,采用RT-qPCR和Western blot实验验证损伤区域miR-144-3p和Notch1的变化情况;用miR-144-3p mimics或miR-144-3p NC转染LPS诱导的巨噬细胞或经鞘内注射脊髓损伤的大鼠,探究miR-144-3p对体内外巨噬细胞炎症反应和大鼠运动功能恢复的影响。结果 数据集GSE19890中miR-144在大鼠脊髓损伤7 d时明显下调。Notch1作为miR-144-3p的靶基因被其负调控。miR-144-3p在脊髓损伤大鼠模型损伤7 d时明显下调,而Notch1的表达则明显上调。miR-144-3p能够明显抑制LPS体外诱导的M1型巨噬细胞炎症反应和脊髓损伤导致的体内巨噬细胞炎症反应,并且促进脊髓损伤大鼠的运动功能恢复。结论 miR-144-3p靶向调控Notch1的表达,并且通过抑制巨噬细胞炎症反应来促进大鼠脊髓损伤后运动功能的恢复。

Objective To investigate the effect of miR-144-3p on macrophage inflammatory response and recovery of motor function in spinal cord injured rats.Methods Analysis of miR-144 expression was performed in the spinal cord injury rat miRNA expression dataset GSE19890.The ENCORI website was used to predict the target gene of miR-144-3p and dual luciferase reporter gene assay was conducted to validate the binding of miR-144-3p to the target gene.A rat model of spinal cord injury was constructed,and RT-qPCR and Western blot assays were used to verified the changes of miR-144-3p and Notch1 in the injured region.The miR-144-3p mimics or miR-144-3p NC were used to transfect LPS-induced macrophages or intrathecally inject rats with spinal cord injury to investigate the effect of miR-144-3p on the inflammatory response of macrophages and recovery of motor function in rats in vitro and in vivo.Results miR-144 was significantly downregulated in the GSE19890 dataset at 7 d of spinal cord injury in rats.Notch1 was negatively regulated by miR-144-3p as its target gene.miR-144-3p was significantly down-regulated at 7 d of injury in a rat model of spinal cord injury,whereas Notch1 expression was significantly up-regulated.miR-144-3p significantly inhibited the M1-type macrophage inflammatory response induced by LPS in vitro and macrophage inflammatory response in vivo due to spinal cord injury,and promoted the recovery of motor function in rats with spinal cord injury.Conclusion miR-144-3p targets and regulates Notch1 expression and promotes recovery of motor function after spinal cord injury in rats by inhibiting macrophage inflammatory responses.