1-磷酸鞘氨醇受体1促进心肌梗死后单核/巨噬细胞在梗死心肌组织中浸润和聚集

目的探讨心肌梗死后S1PR1对单核/巨噬细胞功能的影响及作用机制。方法构建急性心肌梗死模型;实验分为实验组(S1PR1激动剂SEW2871处理组)、阴性对照组(DMSO处理组),各组小鼠分别在药物处理后0、5、28 d三个时间点进行对比研究;流式细胞术检测心肌组织、肝脏、肾脏及外周血等组织中单核/巨噬细胞的数量;荧光显微镜下观察心肌组织单核/巨噬细胞荧光表达情况;构建小鼠pCMV.DR8和pMD2.G慢病毒载体并感染小鼠RAW264.7巨噬细胞,筛选最适感染复数(MOI);实验分为S1PR1基因沉默组、过表达组、U0126(ERK信号通路阻断剂)处理组及空白对照组;采用Transwell小室分析细胞迁移情况;通过RAW264.7与HUVECSs共培养检测细胞粘附功能。结果 (1)实验组小鼠心肌组织中单核/巨噬细胞数量明显多于对照组(P 0.05);(2)体外试验显示,SEW2871促进RAW264.7巨噬细胞的粘附和迁移,S1PR1基因敲减后,上述作用明显降低;(3) U0126预处理后,SEW2871的促进细胞粘附和迁移作用显著减弱。结论 S1PR1通过ERK信号通路促进单核/巨噬细胞的粘附和迁移作用。

S1PR1 promotes the infiltration and aggregation of Monocytes/Macrophages in the Myocardial tissue after Myocardial Infarction

Objective: To investigate the effects and mechanisms of S1PR1 on monocyte/macrophage function after myocardial infarction. Methods: Acute myocardial infarction model was constructed by ligating the proximal portion of the left anterior descending artery. The experimental mice were divided into treatment group (treatment with SEW2871) and negative control group (treatment with DMSO), the mice of each group were studied at three points on day 0, day 5 and day 28 after pretreatment. Flow cytometry was used to detect the number of monocytes/macrophages in myocardium, liver, kidney and peripheral blood. The number of monocytes/macrophages in myocardial tissue was observed under inverted fluorescence microscope. The lentiviral vector of pcmv.dr8 and pmd2.g were constructed and transfected into mouse RAW264.7. The cells were divided into S1PR1 gene silencing group, S1PR1 overexpression group, U0126 inhibition group and negative control group. Cell migration was analyzed by transwell chamber assay. The adhesion ability of RAW264.7 was detected by co-culture of RAW264.7 and HUVECSs. Results: The results of FACS and immune-fluorescent staining confirmed that SEW2871 promoted the aggregation of monocytes/macrophages in the infarcted myocardial tissue. In vitro assays, SEW2871 promoted the adhesion and migration of RAW264.7, and the above effects were significantly reduced after S1PR1 gene knockout. Furthermore, the effect of SEW2871 on promoting cell adhesion and migration was blocked after pretreatment with U0126. Conclusion: S1PR1 promotes the ability of adhesion and migration of monocytes/macrophages through the ERK signaling pathway.