Targeting Myosin to Treat Polycystic Kidney Disease

靶向肌球蛋白治疗多囊肾

基本信息

批准号：
10699859
负责人：
Hongxia Fu
金额：
$ 29.83万
依托单位：
PLUREXA LLC
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-04-12 至 2025-03-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10699859
关键词：
ATP phosphohydrolase Affect Animal Model Animals Area Binding Biochemical Biological Assay Biological Availability Cells Chronic Kidney Failure Clinical Trials Cyst Cytoskeleton Data Disease Docking Dose Drug Targeting Epithelial Cells Epithelium Feasibility Studies Fibrosis Fluorescence Future Genetic Goals Human In Vitro Individual Inherited Investigational Drugs Kidney Kidney Failure Life Liquid substance Literature Liver Marketing Mendelian disorder Microfilaments Modeling Motor Mus Myosin ATPase Myosin Type II Nonmuscle Myosin Type IIA Organ Organ failure Organoids PKD2 protein Patients Persons Pharmaceutical Preparations Phase Phenotype Polycystic Kidney Diseases Preclinical Testing Proteins Renal Replacement Therapy Renal tubule structure Role Safety Shapes Specificity Structure Testing Therapeutic Tube Tubular formation Vasopressin Receptor Work analog antagonist blebbistatin blood pressure control cell motility cytotoxicity disease phenotype drug development experimental study human model in silico in vivo inhibitor invention lead optimization loss of function mutation non-muscle myosin novel novel therapeutic intervention pharmacophore polycystic kidney disease 1 protein reconstitution side effect simulation single molecule small molecule targeted agent therapy development tolvaptan

项目摘要

PROJECT SUMMARY The goal of this proposal is to advance a new therapeutic approach targeting myosin for polycystic kidney disease (PKD). PKD is a major life-threatening Mendelian disorder that affects 12,000,000 individuals, representing a market opportunity of ~$1 billion. In PKD, tiny tubules in the kidneys, liver, and other organs gradually expand into fluid-filled cysts, leading to organ failure. PKD is commonly inherited as a loss-of-function mutation in PKD1 or PKD2, encoding polycystin-1 (PC1) or polycystin-2 (PC2), respectively. General treatment involves managing complications of chronic kidney disease, controlling blood pressure, and preparing for renal replacement therapy. Tolvaptan, a vasopressin receptor antagonist, is approved for use in rapidly progressing cases, but its modest efficacy and occasionally severe side effects make it unsuitable for many PKD patients. How cysts form mechanistically remains incompletely understood, which has hampered drug development. Thus a compelling need and market exists for new treatments and targets to slow or reverse PKD. To better model human PKD and develop therapeutic strategies, we have invented PKD1-/- and PKD2-/- human kidney organoids, which undergo PKD-specific cyst formation from tubules, reconstituting the disease phenotype in a petri dish. Organoid studies reveal that PKD cyst formation is highly sensitive to the microenvironment, and that blebbistatin, a myosin II inhibitor, greatly increases cystogenesis. Non-muscle myosin II (NMII), a known target of blebbistatin that confers strength and shape to cells, is strongly expressed in tubular epithelia and redistributed in organoid cysts. Conversely, in preliminary studies, we have discovered a myosin II activator that reduces PKD cystogenesis, suggesting a novel therapeutic strategy. This compound has a well-established safety and bioavailability profile in large animal studies. Based on our preliminary data and the literature, we hypothesize that it directly activates NMII heavy chains to strengthen and stiffen the cytoskeleton of kidney tubules, thus limiting their tendency to deform into cysts. The major goal of this proposal is to demonstrate this mechanism of action as proof of concept for targeted drug development. This will be achieved in independent aims using purified NMII in vitro and in phenotypic human and animal models. Aim #1: Demonstrate that our hit compound activates NMII in assays suitable for drug optimization. Aim #2. Elucidate the targetable function of NMII during PKD cyst formation in organoids and in vivo. Completion of these two aims will connect the dots between our therapeutic hit compound, NMII, and PKD cyst formation from the single molecule to organoid scale, elucidating a novel mechanism of action for treating cystic disease. This will demonstrate proof of concept, further validate the therapeutic hit, and lay the groundwork for deeper drug development efforts in Phase II (lead optimization and pre-clinical testing).

项目概要该提案的目标是推进一种针对多囊肾的肌球蛋白的新治疗方法疾病（PKD）。多囊肾 (PKD) 是一种严重危及生命的孟德尔疾病，影响着 12,000,000 人，代表着约 10 亿美元的市场机会。在 PKD 中，肾脏、肝脏和其他器官中的小管逐渐扩大成充满液体的囊肿，导致器官衰竭。 PKD 通常作为功能丧失而遗传 PKD1 或 PKD2 突变，分别编码多囊蛋白-1 (PC1) 或多囊蛋白-2 (PC2)。一般治疗涉及管理慢性肾脏病的并发症、控制血压以及为肾病做好准备替代疗法。托伐普坦是一种加压素受体拮抗剂，被批准用于快速进展的但其疗效有限且偶尔会出现严重副作用，使其不适合许多 PKD 患者。囊肿的形成机制尚不完全清楚，这阻碍了药物的开发。因此对于减缓或逆转 PKD 的新疗法和目标存在着迫切的需求和市场。为了更好地模拟人类 PKD 并制定治疗策略，我们发明了 PKD1-/- 和 PKD2-/- 人类肾脏类器官，从肾小管中形成 PKD 特异性囊肿，重建疾病表型在培养皿中。类器官研究表明 PKD 囊肿的形成对微环境高度敏感，并且肌球蛋白 II 抑制剂 blebbistatin 可大大增加囊肿发生。非肌肉肌球蛋白 II (NMII)，一种已知的 blebbistatin 的靶标赋予细胞强度和形状，在肾小管上皮细胞中强烈表达，并且重新分布在类器官囊肿中。相反，在初步研究中，我们发现了一种肌球蛋白 II 激活剂减少 PKD 囊肿发生，提出了一种新的治疗策略。该化合物具有完善的大型动物研究中的安全性和生物利用度概况。根据我们的初步数据和文献，我们假设它直接激活 NMII 重链以强化和硬化肾脏的细胞骨架管，从而限制它们变形为囊肿的倾向。该提案的主要目标是证明这一点作用机制作为靶向药物开发的概念证明。这将通过独立实现目标是在体外以及表型人类和动物模型中使用纯化的 NMII。目标#1：证明我们的命中化合物在适合药物优化的测定中激活 NMII。目标#2。阐明 NMII 在类器官和体内 PKD 囊肿形成过程中的靶向功能。这两个目标的完成将把我们的治疗性命中化合物 NMII 和 PKD 囊肿联系起来从单分子到类器官规模的形成，阐明了治疗囊肿的新作用机制疾病。这将展示概念验证，进一步验证治疗效果，并为第二阶段更深入的药物开发工作（先导化合物优化和临床前测试）。