Targeting Abnormal Calcium Cycling Using Novel Gene Therapy Vectors

使用新型基因治疗载体靶向异常钙循环

基本信息

批准号：
8653366
负责人：
FADI GABRIEL AKAR
金额：
$ 73.38万
依托单位：
ICAHN SCHOOL OF MEDICINE AT MOUNT SINAI
依托单位国家：
美国
项目类别：
财政年份：
2014
资助国家：
美国
起止时间：
2014-01-02 至 2017-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8653366
关键词：
Accounting Acute Address Amiodarone Animal Model Anti-Arrhythmia Agents Antibodies Arrhythmia Biological Markers Ca(2+)-Transporting ATPase Calcium Cardiac Cause of Death Chronic Clinical Clinical Trials Coronary Coronary Arteriosclerosis Coronary artery Coupled Development Disease Dominant-Negative Mutation Effectiveness Etiology Exhibits FKBP1B gene Family suidae Functional disorder Gene Delivery Gene Transduction Agent Gene Transfer Gene Transfer Techniques Health Heart Heart failure Hour Human Hybrids Incidence Individual Injury International Investigation Ion Channel Protein Left Ventricular Dysfunction Macromolecular Complexes Mechanics Mediating Modeling Molecular Molecular Target Myocardial Infarction Myocardial Ischemia Myocardium Nature Outcome Patients Pharmaceutical Preparations Pharmacotherapy Phase Phosphorylation Post-Translational Protein Processing Pre-Clinical Model Prevention Prevention strategy Property Protein-Serine-Threonine Kinases Proteins Pump Randomized Clinical Trials Recombinants Regulation Reperfusion Therapy Reporting Research Design Risk Risk Factors Ryanodine Receptor Calcium Release Channel SERCA2a Sarcoplasmic Reticulum Serotyping Small Interfering RNA Testing Therapeutic Time Translations Tropism United States Up-Regulation Ventricular Arrhythmia adeno-associated viral vector base clinically relevant constriction design gene delivery system gene therapy hemodynamics high risk improved inhibitor/antagonist innovation man mortality neutralizing antibody novel overexpression patient population phospholamban preclinical study sudden cardiac death treatment strategy uptake vector

项目摘要

DESCRIPTION (provided by applicant): Most sudden cardiac deaths occur in patients with coronary artery disease and associated left ventricular dysfunction. Epicardial coronary artery abnormalities resulting in acute or chronic ischemic insults account for up to 80% of clinical arrhythmias. Randomized trials and clinical electrophysiological studies have demonstrated the ineffectiveness of anti-arrhythmic drug therapy in reducing mortality in this high-risk patient population. Paradoxically, conventional pharmacotherapies targeting ion channel proteins are often associated with increased rather than decreased mortality, possibly due to a potent pro-arrhythmic effect of these drugs. Numerous studies have established the importance of abnormal intracellular calcium (Ca2+) cycling in mechano-electrical dysfunction. Defective sequestration of Ca2+ by the sarcoplasmic reticulum (SR) Ca2+ ATPase (SERCA2a), coupled with increased diastolic SR Ca2+ leak via the ryanodine receptor (RYR2), result in cytosolic Ca2+ overload and associated dysfunction in ischemic heart disease. Key molecular targets that modulate SR Ca2+uptake and release include: 1) SERCA2a and its newly discovered post-translational modification by SUMO1, 2) Phospholamban (PLB), an endogenous inhibitor of SERCA2a, 3) FKBP12.6, a key component of the RYR2 macromolecular complex which stabilizes RYR2 activity, and 4) CAMKIIδc, a serine/threonine protein kinase which regulates intracellular Ca2+ cycling, including SR Ca2+ leak through RYR2 phosphorylation. The development of novel gene-based therapies that target these central components of intracellular Ca2+ cycling requires the investigation of their electrophysiological consequences, including pro- arrhythmic risk, in clinically relevant large animal models that closely mimic human ischemic heart disease. A major obstacle that has hindered the translation of these potentially effective molecular therapies has been the availability of adequate vectors for long-term gene transfer. Although AAV vectors were found to be safe in multiple clinical trials, their widespread use for gene delivery is limited by: 1) non-specificity to the heart and 2) pre-existing neutralizig antibodies to conventional AAV serotypes in <50% of candidates. A major innovation of the current application is the proposed use of chimeric AAV based bionanoparticles that exhibit superior cardiac tropism while escaping inherent immunological limitations in patients. We will take advantage of clinically relevant porcine models and gene delivery systems to test the central hypothesis that: a) SUMO1 ± SERCA2a overexpression, b) PLB silencing, c) FKBP12.6 overexpression, and d) CAMKIIδc inhibition are associated with distinct electrophysiological consequences in preclinical models of CAD. These studies will reveal the electrophysiological benefits and potential pitfalls associated with novel (e.g. SERCA2a + SUMO1) molecular therapies for CAD.

描述（由适用提供）：大多数心脏死亡发生在冠状动脉疾病和左心室功能障碍的患者中。心外膜冠状动脉异常导致急性或慢性缺血性损伤占临床心律不齐的80％。随机试验和临床电生理研究表明，抗心律失常药物治疗在降低这一高危患者人群死亡率方面的效果无效。矛盾的是，靶向离子通道蛋白的常规药物治疗通常与这些药物的潜在促进性心律失常作用相关，而不是死亡率的增加而不是死亡率降低。大量研究确定了机械电气功能障碍中异常细胞内钙（CA2+）循环的重要性。肌浆网（SR）Ca2+ ATPase（SERCA2A）对Ca2+的有缺陷，并通过ryanodine受体（RYR2）与舒张期SR Ca2+泄漏增加，导致细胞溶质性CA2+胞质CA2+过负载和相关的缺陷性心脏病中的功能障碍。调节SR Ca2+摄取和释放的关键分子靶标包括：1）SERCA2A及其新发现的sumo1，2）磷团（PLB）（PLB）（serca2a的抑制剂，3）Fkbp12.6，phospholamban（PLB），它是ryr2 macromoleculians and a camkbp12.6稳定ryr2 camkimole2 ryr2 ryr2 ryr2 ryyr 2丝氨酸/苏氨酸蛋白激酶，调节细胞内Ca2+循环，包括通过RYR2磷酸化的SR Ca2+泄漏。针对细胞内Ca2+循环的这些中心成分的新型基于基因的疗法的发展需要研究其电生理后果，包括临床相关的大型动物模型，这些模型紧密模仿人类缺血性心脏病。阻碍这些潜在有效分子疗法的翻译的主要障碍是为长期基因转移的足够媒介提供了。尽管在多个临床试验中发现AAV载体是安全的，但它们用于基因输送的宽度被限制为：1）对心脏的非特异性和2）在<50％的候选者中对常规AAV血清型的预先存在的中和抗体。当前应用的主要创新是提议使用基于嵌合AAV的Biionanoparticles，该粒子暴露了高级心脏的最大性，同时逃避了患者固有的免疫学限制。我们将利用临床相关的猪模型和基因输送系统来检验以下中心假设：a）SUMO1±SERCA2A过表达，b）PLB沉默，c）FKBP12.6过表达，d）CAMKIIΔC抑制与CAD的预先细胞模型中的不同电学后果有关。这些研究将揭示与CAD的新型（例如SERCA2A + SUMO1）分子疗法相关的电生理益处和潜在陷阱。