Exosomes from miR-primed endothelial progenitor cells for treating ischemic stroke

项目摘要 缺血性中风（IS），由于脑血管闭塞导致的脑血流损失，仍然是脑血管病的主要病因之一。 最严重的健康问题。目前用于中风的治疗，例如溶栓剂、PTAS， 和神经保护药物已被证明是有帮助的;然而，它们也受到治疗时间狭窄的限制。 窗口期、再卒中风险和低有效性。寻找一种理想的治疗策略， 促进急性损伤的血管新生和神经发生，对于神经功能的恢复，因而势在必行 needed.内皮祖细胞（EPC）具有分化为成熟内皮细胞（EC）的能力， 已知参与血管生成和神经发生。EPC移植已显示出有希望的结果 用于IS治疗。新出现的证据表明，干细胞释放的EX可用于治疗IS。EXs是 内体起源的小膜囊泡通过转移miRNA（miR）介导细胞-细胞通讯。 干细胞EX比干细胞具有优势，因为它缺乏自我增殖，并且更容易储存， 传递比细胞。在这个项目中，我们的目标是使用EPC释放的EX（EPC-EX）作为IS治疗的新途径 因为它们选择性地携带富集的miR-126。我们发现EPC-EX可以保护EC免受 缺氧/复氧（H/R）诱导损伤和功能障碍主要通过其携带的miR-126; EPC-EXs可保护缺血后脑血流量，减少梗死体积。有趣的是，反- 已经发现在中风患者中细胞凋亡/抗氧化应激miR-210降低。我们发现 miR-210致敏的EPC-EX（EPC-EXsmiR 210）在保护EC免受H/R损伤方面比EPC-EX更有效。 诱导损伤。总之，通过结合EPCs（干细胞）的有益作用，EX（ 脑微环境）和miR（多信号通路靶点），我们认为EPC-EXsmiR 210可以 作为IS的一种新的治疗途径。设计了三个目的来验证我们的假设，即EPC-EXsmiR 210 通过保护脑细胞免受急性缺血性损伤和促进缺血性脑损伤， 通过EPC-EXs、miR-126和miR-210促进神经功能恢复的血管生成/神经发生 下游通路，VEGF/VEGFR 2/PI 3 K/Akt，PIK 3R 2/PI 3 K/Caspase和BDNF/TrkB/PI 3 K/Akt。目标1： 确定EPC-EXsmiR 210是否对保护EC和神经元免受H/R诱导的损伤具有增强的作用。 通过靶向多个通路来治疗损伤/功能障碍。目的2：确定EPC-EXsmiR 210是否发挥增强的 通过靶向多个通路保护脑免受IS诱导的急性损伤。目标3：确定 EPC-EXsmiR 210是否对促进神经血管发生和功能恢复发挥增强作用， 是通过针对多个途径。 .

Project Summary Ischemic stroke (IS), loss of cerebral blood flow due to occlusion of cerebral blood vessels, remains one of the most severe health problems in the world. Current treatments for stroke, such as thrombolytic agents, PTAS, and neuroprotective drugs have shown to be helpful; however, they are also limited by a narrow therapeutic time window, risk of re-stroke and low effectives. Looking for an ideal therapeutic strategy that protect brain from acute injury and promote angiogenesis and neurogenesis for neurological functional recovery, is thus imperative needed. Endothelial progenitor cells (EPCs) with the ability to differentiate into mature endothelial cells (ECs), are known to participate in angiogenesis and neurogenesis. EPC transplantation has shown promising results for IS therapy. Emerging evidence suggests that stem cell released EXs could be used for treating IS. EXs are endosomal origin small-membrane vesicles mediating cell-cell communication by transferring miRNAs (miRs). Stem cell EXs hold advantages over stem cells because of lacking self-proliferation and are easier to store and deliver than cells. In this project, we aim to use EPC-released EXs (EPC-EXs) as a novel avenue for IS therapy as they selectively carry enriched miR-126. We have found that EPC-EXs protect ECs from hypoxia/reoxygenation (H/R)-induced injury and dysfunction mainly through their carried miR-126; transfusion of EPC-EXs could preserve cerebral blood flow (CBF) and decrease infarct volume after IS. Of interest, the anti- apoptosis/anti-oxidative stress miR-210 has been found to be decreased in the stroke patients. We discovered that miR-210 primed EPC-EXs (EPC-EXsmiR210) are more effective than EPC-EXs in protecting ECs from H/R- induced injury. Taken together, by combining the beneficial effects of EPCs (stem cells), EXs (novel player of brain microenvironment), and miRs (multiple signaling pathway targets), we believe that EPC-EXsmiR210 could serve as a novel therapeutic avenue for IS. Three aims are designed to test our hypothesis that EPC-EXsmiR210 have enhanced therapeutic effects on IS by protecting brain cells from acute ischemic injury and promoting angiogenesis/neurogenesis for neurological functional recovery through EPC-EXs, miR-126 and miR-210 downstream pathways, VEGF/VEGFR2/PI3K/Akt, PIK3R2/PI3K/Caspase and BDNF/TrkB/PI3K/Akt. Aim 1: Determine whether EPC-EXsmiR210 have enhanced effects on protecting ECs and neurons from H/R-induced injury/dysfunction by targeting multiple pathways. Aim 2: Determine whether EPC-EXsmiR210 exert enhanced effects on protecting brain from IS-induced acute damage by targeting multiple pathways. Aim 3: Determine whether EPC-EXsmiR210 exert enhanced effects on promoting neurovascular genesis and functional recovery after IS by targeting multiple pathways. .