Abstract：
BACKGROUND: Cerebral ischemia (CI) induces a profound neuroinflammatory response, but the underlying molecular mechanism remains unclear. Exosomes from adipose-derived stem cells (ADSC-exos) have been found to play a crucial role in cell communication by transferring molecules including microRNAs (miRNAs), which have been shown to modulate the inflammatory response after CI and are viable molecular targets for altering brain function. The current study aimed to explore the contribution of ADSC-exosomal miR-21-5p to the neuroinflammation after CI.
METHODS: The differentially expressed miR-21-5p in CI was screened based on literature search. The target mRNAs of miR-21-5p were predicted using online databases and verified by luciferase reporter assay. Then, BV2 cells were treated with hemin to simulate the inflammatory response after CI, and its animal model was induced using the MCAO method. Ischemia was evaluated in rats using 2, 3, 5-triphenyl tetrazolium chloride (TTC) staining. ADSCs-exos were further isolated and identified by western blot analysis and transmission electron microscope.
RESULTS: MiR-21-5p was significantly down-regulated in CI and alleviated neuropathic damage after CI by the PIK3R1/PI3K/AKT signaling axis. And miR-21-5p derived from ADSCs-exos alleviated neuroinflammation after CI via promoting microglial M2 polarization.
CONCLUSIONS: We demonstrated that ADSC-exosomal miR-21-5p mitigated post-CI inflammatory response through the PIK3R1/PI3K/AKT signaling axis and could offer neuroprotection after CI through promoting polarization of M2 microglia.
METHODS: The differentially expressed miR-21-5p in CI was screened based on literature search. The target mRNAs of miR-21-5p were predicted using online databases and verified by luciferase reporter assay. Then, BV2 cells were treated with hemin to simulate the inflammatory response after CI, and its animal model was induced using the MCAO method. Ischemia was evaluated in rats using 2, 3, 5-triphenyl tetrazolium chloride (TTC) staining. ADSCs-exos were further isolated and identified by western blot analysis and transmission electron microscope.
RESULTS: MiR-21-5p was significantly down-regulated in CI and alleviated neuropathic damage after CI by the PIK3R1/PI3K/AKT signaling axis. And miR-21-5p derived from ADSCs-exos alleviated neuroinflammation after CI via promoting microglial M2 polarization.
CONCLUSIONS: We demonstrated that ADSC-exosomal miR-21-5p mitigated post-CI inflammatory response through the PIK3R1/PI3K/AKT signaling axis and could offer neuroprotection after CI through promoting polarization of M2 microglia.
摘要：
背景：脑缺血（CI）诱导深度神经炎症反应，但潜在的分子机制仍不清楚。已经发现来自脂肪干细胞的外泌体（ADSC-exos）通过转移包括microRNAs（miRNA）在内的分子在细胞通讯中起着至关重要的作用。已被证明可以调节CI后的炎症反应，并且是改变脑功能的可行分子靶标。本研究旨在探讨ADSC-外泌体miR-21-5p在CI后神经炎症中的作用。
方法：在文献检索的基础上筛选出差异表达的miR-21-5p在CI中的表达。使用在线数据库预测miR-21-5p的靶mRNA，并通过荧光素酶报告基因测定进行验证。然后，用血红素处理BV2细胞以模拟CI后的炎症反应，并使用MCAO方法诱导其动物模型。使用2,3,5-三苯基氯化四唑（TTC）染色评估大鼠的缺血。通过蛋白质印迹分析和透射电子显微镜进一步分离和鉴定ADSCs-exos。
结果：MiR-21-5p在CI中显著下调，并通过PIK3R1/PI3K/AKT信号轴减轻CI后的神经病性损伤。来自ADSCs-exos的miR-21-5p通过促进小胶质细胞M2极化减轻CI后的神经炎症。
结论：我们证明ADSC-外泌体miR-21-5p通过PIK3R1/PI3K/AKT信号轴减轻CI后的炎症反应，并通过促进M2小胶质细胞的极化提供CI后的神经保护。
方法：在文献检索的基础上筛选出差异表达的miR-21-5p在CI中的表达。使用在线数据库预测miR-21-5p的靶mRNA，并通过荧光素酶报告基因测定进行验证。然后，用血红素处理BV2细胞以模拟CI后的炎症反应，并使用MCAO方法诱导其动物模型。使用2,3,5-三苯基氯化四唑（TTC）染色评估大鼠的缺血。通过蛋白质印迹分析和透射电子显微镜进一步分离和鉴定ADSCs-exos。
结果：MiR-21-5p在CI中显著下调，并通过PIK3R1/PI3K/AKT信号轴减轻CI后的神经病性损伤。来自ADSCs-exos的miR-21-5p通过促进小胶质细胞M2极化减轻CI后的神经炎症。
结论：我们证明ADSC-外泌体miR-21-5p通过PIK3R1/PI3K/AKT信号轴减轻CI后的炎症反应，并通过促进M2小胶质细胞的极化提供CI后的神经保护。
