Evaluating the efficacy of a miR-10 therapy after myocardial infarction

冠状动脉粥样硬化血栓闭塞引起的心肌梗死（MI）导致的心肌丢失是全球缺血后心力衰竭和心源性猝死的主要危险因素。虽然在治疗急性心肌梗死方面已经取得了重大进展，包括基于导管的干预和新的预防性药物治疗，但由于缺血后心力衰竭，长期死亡率和住院率增加。目前有效的改善心肌梗死预后的治疗方法主要是抑制血小板和神经内分泌激活。新的分子治疗选择通过诱导和增强新的毛细血管和侧支动脉血管形成来增加冠状动脉血流量。虽然几种引入经典的单一促血管生成生长因子的基因治疗方法在临床试验中未能证明有效性，但基于miRNA的基因治疗的最新进展在大型动物试验中具有很大的前景和证明的效力。在我们和其他人之前的工作中，miR-10被确定为斑马鱼、小鼠和人内皮细胞中血管生成的有效正调节剂。值得注意的是，miR-10 s促血管生成功能特别是通过旁分泌机制介导的。除了其促血管生成功能之外，其他几个研究表明，细胞中miR-10的强制表达积极阻断细胞凋亡，并且miR-10也以旁分泌方式能够有益地调节组织炎症以促进愈合。本项目提案遵循以下假设，即miR-10代表一种有吸引力的、多事实作用的新靶点，其部分通过积极调节血管生成、改善心肌细胞存活和控制炎症过程来有益地改变MI后的结果。所提出的实验旨在评估MI后心脏miR-10过表达的治疗潜力。在第一个具体目标I）中，我们将评估对照动物体内miR-10过表达的影响，以评估miR-10治疗的潜在不良反应，我们将收集有关参数的初始数据，包括药效学、药代动力学和毒理学。在第二个具体目标II）中，我们将确定MI后体内AAV 9-miR-10介导的过表达的有益影响。因此，我们将评估心脏功能和心肌血管化的变化、坏死瘢痕组织分布以及正常条件下和MI后的细胞死亡和炎症细胞积聚。本研究的概念设计遵循非临床环境中的概念验证方法，以系统地评估miR-10疗法治疗缺血性心脏病的潜力。

Myocardial loss due to myocardial infarction (MI) triggered by atherothrombotic occlusion of coronary vessels is the major risk factor for post-ischemic heart failure and sudden cardiac death world wide. While major advances have been made in treating acute myocardial infarction including catheter based interventions and novel adjunctive medical treatments, long-term mortality and hospitalization rates increased due to post-ischemic heart failure. Todays potent therapeutic approaches to improve the outcome after MI aim at inhibiting platelet and neuroendocrine activation. Novel molecular therapy options target at increasing coronary blood flow by inducing and enhancing new capillary and collateral arterial vessel formation. While several gene therapy approaches introducing classical single proangiogenic growth factors failed to demonstrate effectiveness in clinical trials, recent progress in miRNA based gene therapies hold great promise and proved potency in large animal trials. In previous work by us and others, miR-10 was established as a potent positive modulator of angiogenesis in zebrafish, mouse and human endothelial cells. Noticeably, miR-10s pro-angiogenic function is particularly mediated through paracrine mechanisms. Besides it pro-angiogenic function, it was shown by several others that forced expression of miR-10 in a cell actively blocked apoptosis and that miR-10, also in a paracrine fashion, is able to beneficially modulate tissue inflammation to promote healing. The present project proposal follows the hypothesis, that miR-10 represents an attractive, multifactual acting, new target to beneficially change the outcome post-MI in part by positively modulate angiogenesis, improving cardiomyocyte cell survival and controlling inflammatory processes. The proposed experiments aim at evaluating the therapeutic potential of cardiac miR-10 overexpression after MI. In the first specific aim I) we will evaluate the effects of miR-10 overexpression in vivo in control animals to assess potential adverse effects of a miR-10 therapy and we will collect initial data on parameters, including pharmacodynamics, pharmacokinetics and toxicology. In a second specific aim II) we will determine the beneficial impact of AAV9-miR-10 mediated overexpression in vivo post-MI. Therefor, we will assess changes in heart function and myocardial vascularization, in necrotic scar tissue distribution as well as cell death and accumulation of inflammatory cells under normal conditions and after MI. The conceptual design of this study follows a proof of concept approach in a non-clinical setting to systematically evaluate the potential of miR-10 therapy to treat ischemic heart disease.