Development of Ryanodine Receptor 2 Selective Probes

项目摘要 Ryanodine受体2（RyR 2）突变导致RyR 2介导的失调 钙释放与多种心血管疾病有关。结果，几个 小分子探针已经用于心脏疾病的研究和治疗， RyR钙通道的靶向。氟卡尼丁卡因和丹曲林， 常见的这些小分子探针，不是没有问题。例如，氟卡尼是 结构性心脏缺陷或心力衰竭患者禁用。此外，选择性 特异性RyR同种型（RyR 1、RyR 2或RyR 3）是罕见的，迄今为止， 不存在.选择性调节RyR 2的新探针将非常有用， 治疗和作为工具，以更好地了解RyR 2的功能和机制， 细胞内钙流 该提案的重点是开发一类新的抗肿瘤剂， 在约翰斯顿实验室发现的热门化合物， 天然产物（-）-轮枝环内酯。这种环状寡聚缩肽是一种有效的和选择性的 在哺乳动物中RyR 2介导的钙释放的抑制剂，而天然的轮枝环内酯是无活性的。 我们的目标是使用基于结构的设计方法，以帮助澄清的互动， 轮枝酸与RyR 2。这种方法可能会在我们寻找有效的， 用于治疗心脏病的RyR 2的选择性调节剂。我们的放映将是 首先基于定义明确的RyR 2介导的自发钙释放测定。我们的目标 为了包括环大小同系物和“非天然”对映异构体的离散集合， 在基于天然产物的治疗开发中， 目标（RyR 2），可能导致新的探针。我们还建议使用ent-verticilide在 药理学研究，以确定ADME，同时推进对 作用机制和RyR 2功能。我们的方法非常适合于最终 我们的目标是开发一种有效的、选择性的RyR 2抑制剂， 明确了恩替维他利特治疗心律失常的作用机制。

PROJECT SUMMARY Ryanodine Receptor 2 (RyR2) mutations that result in dysregulated RyR2-mediated calcium release are associated with a variety of cardiovascular diseases. As a result, several small molecule probes have been used in the study and treatment of cardiac diseases through the targeting of RyR calcium channels. Flecainide, tetracaine, and dantrolene, the most common of these small molecule probes, are not without problems. Flecainide, for example, is contra-indicated in patients with structural heart defects or heart failure. Furthermore, selectivity of specific RyR isoforms (RyR1, RyR2, or RyR3) is rare, and to date, an RyR2-selective probe does not exist. New probes to selectively modulate RyR2 would be of great use both therapeutically and as tools to better understand the function of RyR2 and the mechanism of intracellular calcium flux. This proposal focuses on the development of a new class of antiarrhythmic agents using the hit compound discovered in the Johnston lab, ent-verticilide – the non-natural enantiomer of the natural product (–)-verticilide. This cyclic oligomeric depsipeptide is a potent and selective inhibitor of RyR2-mediated calcium release in mammals while the natural verticilide is inactive. We aim to use a structure-based design approach to help clarify the interaction of ent- verticilide with RyR2. This approach may lead to new findings in our search for potent, selective modulators of RyR2 for the treatment of cardiac disease. Our screening will be grounded first in the well-defined RyR2-mediated spontaneous calcium release assay. We aim to include both discrete collections of ring-size congeners and ‘unnatural’ enantiomers, two underexplored variables in natural-product based therapeutic development, to screen against the target (RyR2), potentially leading to new probes. We also propose to use ent-verticilide in pharmacological studies to determine ADME, while advancing the understanding of the mechanism of action and RyR2 function. Our approach is well suited towards the ultimate goals of both developing a potent, selective inhibitor of RyR2 as well as working towards defining the mechanism of action of ent-verticilide to treat cardiac arrythmias.