Microvesicles from Adipose-derived Stem Cells for Ischemic Heart Repair

 描述(由申请人提供)：尽管在医学、介入和外科治疗方面取得了重大进展，但全球范围内的缺血性心脏病的流行迫切需要创新的治疗方法。由于干细胞方法引起肿瘤的关注，一种基于微囊(MV)的治疗性血管生成正在出现，用于治疗缺血性疾病。MVS是从细胞中释放出来的亚微米颗粒，包含蛋白质、信使核糖核酸、微RNA和生物活性脂质。此外，MV最近被认为是细胞间通讯中的一种信号传递载体。在我们目前的试点资助期间，我们已经证明了来自脂肪来源的干细胞(ASCs)的MVs，特别是来自内皮分化介质(EDM)预适应的ASCs的MVs，在体外、体外和体内(Matrigel Plug)都能促进血管生成。促血管生成的一个潜在机制可能是通过MVS将microRNA-31从ASCs运送到血管内皮细胞，其中FIH1(抑制HIF-1的因子)是靶向和抑制的。在这一应用中，我们的中心假设I是移植ASC来源的MVS促进缺血性心肌梗死的血管生成。我们将用更广泛的努力来补充这一方法，继续为我们的假说驱动的机械论实验提供支持。目的1确定从EDM预适应ASCs中释放的MVS在促进缺血心脏血管生成中的作用。MVS将在严重联合免疫缺陷(NOD SCID)小鼠的心肌梗死(MI)后给予。随后将对心功能、细胞增殖和凋亡、fi面积和毛细血管密度进行评估。目的2是研究miR-31信号在MVS细胞间通讯中的作用。我们将探讨已被FIH1抑制的缺氧诱导因子-1(HIF-1)的活性，并将拓宽我们对miR-31/FIH1/HIF-1通路在MV移植缺血心肌中的作用的理解。目的3确定心肌梗死后ASC来源的MVS中miR-31在心脏修复中的作用。我们将研究不同剂量、不同给药时机和不同给药途径对心肌梗死后心脏修复的影响。为了增加我们研究的吞吐量，miR-31将被操纵在电火花预适应的MV供体ASCs中或直接在MVS中操作。在本研究方案的结论中，我们将表征miR-31/FIH1/HIF1通路在基于MV的缺血性心脏病治疗中的作用。通过MV传递血管生成的miRNAs来调节血管内皮细胞的miRNA组成，可能是治疗缺血性心脏病的一种创新策略。

 DESCRIPTION (provided by applicant): The worldwide epidemic of ischemic heart diseases urgently requires innovative treatments in spite of the significant advances in medical, interventional and surgical therapy for these diseases. A microvesicle (MV)-based therapeutic angiogenesis is emerging for ischemic diseases because of tumorigenic concern of the stem cell approach. MVs are submicron particles that are released from cells, and contain a package of protein, mRNA, microRNA and bioactive lipid. In addition, MV has recently been recognized as a signaling transferring vehicle in intercellular communication. In our current pilot funding period, we have demonstrated that MVs from adipose-derived stem cells (ASCs), particularly from endothelial differentiation medium (EDM)-preconditioned ASCs, promote angiogenesis in vitro, ex vivo and in vivo (matrigel plugs). An underlying mechanism of the proangiogenesis may be the delivery of microRNA-31 via MVs from ASCs to vascular endothelial cells in which FIH1 (factor inhibiting HIF-1) is targeted and suppressed. In this application, our central hypothesis i that the transplantation of ASC-derived MVs promotes angiogenesis in ischemic heart myocardial infarction. We will complement this approach with broader efforts to continue to feed our pipeline of hypothesis-driven mechanistic experiments. Aim 1 is to determine the role of MVs released from EDM-preconditioned ASCs in promoting angiogenesis in the ischemic heart. The MVs will be administered after myocardial infarction (MI) in severe combined immunodeficiency (NOD SCID) mice. The cardiac function, cell proliferation and apoptosis, fibrotic area, and capillary density will subsequently be evaluated. Aim 2 is to investigate the role of miR-31 signaling in intercellular communication through the MVs. We will explore the activity of hypoxia inducible factor-1 (HIF-1), which has been reported to be inhibited by FIH1, and will broaden our understanding of the role of miR-31/FIH1/HIF-1 pathway in MV-transplanted ischemic myocardium. Aim 3 is to determine the effect of miR-31 in ASC-derived MVs on cardiac repair after MI. The effects of different dosing, timing and delivery routes of administration of MVs on cardiac repair after MI will be investigated. To increase the throughput of our investigation, miR-31 will be manipulated in EDM-preconditioned MV-donor ASCs or in MVs directly. At the conclusion of this research proposal we will have characterized the role of miR-31/FIH1/HIF1 pathway in MV- based therapy for ischemic heart diseases. Modulation of miRNA composition in vascular endothelial cells by delivering angiogenic miRNAs via MV may be an innovative strategy for the treatment of ischemic heart diseases.