ShRNA-Based Targeting of mAKAPβ in Heart Failure

病理性心脏重塑是疾病中心力衰竭的常见途径。尽管目前 减轻重塑的药物治疗和其他进展，心力衰竭的死亡率仍然存在 很高。越来越多的患者迫切需要新的、更有效的治疗方案 改善心力衰竭患者或易患心力衰竭患者的生存和生活质量。肌动蛋白A-激酶 锚定蛋白β(mAKAPβ)是在诱导过程中起关键作用的多分子信号复合体的组织者 以及病理性心脏重塑的进展。通过结合一系列不同的信号分子，mAKAPβ 动态协调多个信号模块，转导cAMP，丝裂原激活的蛋白激酶 (MAPK)、钙离子、肌醇磷脂和低氧应激信号。相应地，心肌细胞特异性的mAKAPβ 小鼠基因敲除抑制多种心血管模型的重塑和心力衰竭的发生 疾病。CRI是一家开发用于预防和/或治疗的新型专利保护疗法的公司。 心力衰竭的症状。在这个快速通道SBIR中，CRI将测试一种新的基因治疗载体，该载体旨在抑制mAKAPβ 利用RNA干扰技术在心肌细胞中选择性表达。AAV9sc.shmAKAP生物是一种自我 表达mAKAP特异性的补充性、嗜心性、血清9型腺相关病毒(AAV9) 心肌细胞特异性启动子控制下的小发夹RNA(ShRNA)。在此应用程序中，CRI将 在临床相关的心肌梗死(MI)后心力衰竭的大型动物模型中测试新的生物学。 第一阶段-特定目标：我们将对约克郡猪的生物学行为进行剂量反应曲线，以确定 在心脏中持续抑制mAKAPβ表达所需的最小剂量。第二阶段--具体目标 1：mAKAP RNAi对大型动物模型心力衰竭的疗效。这个项目的核心是测试 MAKAPβRNA干扰是否能减轻心肌梗死后猪的病理重塑，预防心力衰竭。 用猪进行缺血再灌流诱导心肌梗死或假手术，然后用 AAV9sc.shmAKAP生物制剂在即刻或1个月后按所确定的剂量经冠状动脉内注射 在第一阶段中，将对猪进行连续超声心动图检查，并在心梗后3个月结束时进行研究。 导管术测定左心室压力-容量环血流动力学。这一目标的目标是 MAKAP RNAi将在心肌梗死大动物模型中保存心脏结构和功能的证明 疾病。特异性靶点2：AAV9sc.shmAKAP介导的分子和细胞病理学抑制 与心力衰竭有关。利用从目标1中使用的相同动物收集的组织， MAKAP RNAi在猪中的好处将通过重量、组织学和分子分析来证明 纤维化和其他心脏重塑和心力衰竭的标志。此外，最初的毒理学筛查将是 这样做是为了保障生物的安全。该项目将显示mAKAPβ靶向是一种可行的治疗策略。 用于治疗心肌梗塞后的心力衰竭，并证明了一项首个人类心力衰竭临床试验的合理性。

Pathological cardiac remodeling constitutes a common pathway to heart failure in disease. Despite current pharmacologic therapy and other advances that attenuate remodeling, mortality due to heart failure remains high. New, more effective therapeutic options are desperately needed in an increasing patient population to improve both the survival and quality of life for patients with or susceptible to heart failure. Muscle A-kinase anchoring protein β (mAKAPβ) is the organizer of multimolecular signaling complexes critical for the induction and progression of pathological cardiac remodeling. By binding a diverse set of signaling molecules, mAKAPβ dynamically orchestrates multiple signaling modules that transduce cAMP, mitogen-activated protein kinase (MAPK), Ca2+, phosphoinositide, and hypoxic stress signals. Accordingly, cardiomyocyte-specific mAKAPβ knock-out in mice inhibited remodeling and the development heart failure in multiple models of cardiovascular disease. CRI is a company developing novel, patent protected therapeutics for the prevention and/or treatment of heart failure. In this Fast-Tract SBIR, CRI will test a new gene therapy vector designed to inhibit mAKAPβ expression selectively in the cardiac myocyte by RNA interference. The AAV9sc.shmAKAP biologic is a self- complementary, cardiotropic, serotype 9 adeno-associated virus (AAV9) that expresses an mAKAP-specific small hairpin RNA (shRNA) under the control of a cardiac myocyte-specific promoter. In this application, CRI will test the new biologic in a clinically relevant large animal model for post-myocardial infarction (MI) heart failure. Phase I - Specific Aim: We will perform a dose response curve for the biologic in Yorkshire swine to determine the minimum dose required for consistent inhibition of mAKAPβ expression in the heart. Phase II - Specific Aim 1: Efficacy of mAKAP RNAi for heart failure in a large animal model. The core of this project is to test whether mAKAPβ RNAi will mitigate pathological remodeling induced by MI in swine, preventing heart failure. Swine will be subjected to ischemia-reperfusion to induce MI or sham procedure and then treated with the AAV9sc.shmAKAP biologic by intracoronary infusion immediately after or 1 month later at the dose determined in Phase I. The pigs will be followed by serial echocardiography and studied at endpoint 3 months post-MI by catheterization for left ventricular pressure-volume loop hemodynamics. The goal for this Aim is the demonstration that mAKAP RNAi will preserve cardiac structure and function in a large animal model of MI disease. Specific Aim 2: AAV9sc.shmAKAP-mediated inhibition of the molecular and cellular pathology associated with heart failure. Taking advantage of tissue collected from the same animals used in Aim 1, the benefits of mAKAP RNAi in swine will be demonstrated by gravimetric, histological, and molecular analyses for fibrosis and other markers of cardiac remodeling and heart failure. In addition, initial toxicology screens will be done to support the biologic’s safety. This project will show that mAKAPβ targeting is a viable therapeutic strategy for heart failure post-MI and justify a first-in-human clinical trial for heart failure.