METHODS: Human umbilical cord MSCs (HucMSCs) were cultured to isolate the corresponding exosomes (HucMSCs-Exos), which were confirmed by their morphology, size distribution, and expression of markers. In vivo, 2,4,6-trinitrobenzenesulfonic acid solution (TNBS) and dextran sodium sulfate (DSS) -induced mouse colitis models were used to detect the therapeutic effects of HucMSCs-Exos. ELISA, qRT-PCR, western blotting, and immunofluorescence determined the expression of key molecules. Luciferase reporter assay was used to confirm the relationship between miR-21-5p and SPRY2.
RESULTS: Exosomes treatment through mesenteric injection demonstrated therapeutic effects on mesenteric inflammation and colitis. These therapeutic benefits were contingent on macrophages, significantly facilitating the M2 polarization of mesenteric macrophages. The expression data from GSE159814 and GSE211008 revealed that exosomal miR-21-5p was enriched in HucMSCs-Exos and could be delivered to macrophages. Additionally, the results indicated that miR-21-5p could directly target the 3\'UTR of SPRY2 and activate the phosphorylation of ERK to modify macrophage phenotypes. Mechanistically, exosomal miR-21-5p derived from HucMSCs could promote macrophage M2 polarization via the SPRY2/ERK axis.
CONCLUSIONS: Mesenteric injection of HucMSCs-Exos significantly alleviates mesenteric inflammation and colitis by promoting mesenteric macrophage M2 polarization, making it a promising approach to treat colitis and suggesting therapeutic potential role of exosomal miR-21-5p in CD.
方法:培养人脐带间充质干细胞(HucMSCs)以分离相应的外泌体(HucMSCs-Exos),它们的形态证实了这一点,大小分布,和标记的表达。在体内,使用2,4,6-三硝基苯磺酸溶液(TNBS)和葡聚糖硫酸钠(DSS)诱导的小鼠结肠炎模型来检测HucMSCs-Exos的治疗效果。ELISA,qRT-PCR,西方印迹,和免疫荧光确定关键分子的表达。荧光素酶报告基因测定用于确认miR-21-5p和SPRY2之间的关系。
结果:通过肠系膜注射的外泌体治疗证明了对肠系膜炎症和结肠炎的治疗效果。这些治疗益处取决于巨噬细胞,显著促进肠系膜巨噬细胞的M2极化。来自GSE159814和GSE211008的表达数据揭示了外泌体miR-21-5p在HucMSC-Exos中富集并且可以递送至巨噬细胞。此外,结果表明,miR-21-5p可以直接靶向SPRY2的3'UTR,并激活ERK的磷酸化以修饰巨噬细胞表型。机械上,来自HucMSCs的外泌体miR-21-5p可以通过SPRY2/ERK轴促进巨噬细胞M2极化。
结论:肠系膜注射HucMSCs-Exos通过促进肠系膜巨噬细胞M2极化显著减轻肠系膜炎症和结肠炎,使其成为治疗结肠炎的有希望的方法,并提示外泌体miR-21-5p在CD中的潜在治疗作用。