Dystrophin and Heart Disease

肌营养不良蛋白和心脏病

• 批准号: 9367436
• 负责人: JOSEPH Mark METZGER
• 金额: $ 38.08万
• 依托单位: UNIVERSITY OF MINNESOTA
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-07-01 至 2021-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9367436
• 关键词: Animal Model; Attention; Benchmarking; Biochemical; Cardiac; Cardiac health; Cardiomyopathies; Cause of Death; Clinical; Clinical Trials; Complex; Cytoskeletal Proteins; Cytoskeleton; Data; Disease; Dissection; Duchenne muscular dystrophy; Dystrophin; Effectiveness; Exons; Extracellular Matrix; Future; Genes; Genetic; Glycoproteins; Half-Life; Health; Heart; Heart Diseases; Heart failure; Inherited; Knowledge; Lead; Length; Link; LoxP-flanked allele; Membrane; Methods; Mission; Muscle; Myocardium; Patients; Peptides; Performance; Physiological; Proteins; Role; Somatic Cell; Stress; Striated Muscles; Structure; Structure-Activity Relationship; Technology; Testing; Therapeutic; Time; Titrations; Transgenic Mice; Translating; United States National Institutes of Health; Work; base; clinical efficacy; clinically relevant; comparative; design; effective therapy; exon skipping; gene therapy; genetic technology; heart function; in vivo; micro-dystrophin; mortality; protein complex; public health relevance; spatiotemporal; success

Abstract Significant health relevance of this application is evident in our mechanistic dissection of the role of the cytoskeletal protein dystrophin in heart health and disease. Numerous inherited and acquired cardiac diseases are caused by deficits in dystrophin, including, notably, Duchenne muscular dystrophy (DMD), in which there is the complete loss of the dystrophin protein. Dystrophin is a 427 kDa cytoskeletal protein and is a vital link between the cytoskeleton, the muscle membrane and the extracellular matrix. Heart disease accounts for a significant mortality in DMD, for which there is no cure or long-term effective treatment. Recent advances in genetic technologies have fueled enthusiasm for gene-based therapeutic restitution of truncated dystrophins as a treatment for DMD. For DMD patients, several exon skipping clinical trial studies are ongoing and proof-of- concept somatic cell gene editing studies provide evidence of effectiveness in animal models. To date, none of these efforts have successfully translated to clinical efficacy in DMD patients. We posit reduced in vivo stability of internally truncated dystrophins is a significant barrier to ultimate clinical efficacy. We provide preliminary evidence that truncated dystrophins can be highly unstable in vivo, with markedly faster turnover rates than full length dystrophin. Reduced stability of a truncated dystrophin is expected to have significant implications for long-term clinical success by negatively impacting duration of therapeutic action in vivo. Further, the therapeutic expression threshold to confer significant cardio-protection with truncated dystrophin molecules is not known and truncated dystrophin proteins can confer only partial physiological restitution in dystrophin-deficient hearts in vivo. We have established a proof-of-concept approach to directly determine the stability and physiological expression threshold for truncated dystrophins in the heart in vivo. Guiding hypothesis: Clinically-designed gene therapy, gene-edited or exon skipped truncated dystrophin molecules will have significantly shorter half-lives in the heart in vivo, compared to intact full length dystrophin, compromising duration of action effects. The Specific Aims are to establish the in vivo stability/half-life of clinically relevant truncated dystrophins in the dystrophic heart. This knowledge is essential for the success of gene-based clinical trials for DMD. These studies will have a lasting impact on the field by illuminating the key dystrophin structure-function benchmarks required for long- term effectiveness of current and future gene-based therapies for DMD patients.

摘要 这种应用的显著健康相关性在我们对药物的作用的机械解剖中是显而易见的。 细胞骨架蛋白抗肌萎缩蛋白在心脏健康和疾病中的作用。许多遗传性和获得性心脏病 是由肌营养不良蛋白的缺陷引起的，特别是包括杜氏肌营养不良症（DMD），其中存在 肌营养不良蛋白质的完全丧失。Dystrophin是一种分子量为427 kDa的细胞骨架蛋白， 在细胞骨架、肌膜和细胞外基质之间。心脏病占 DMD的死亡率很高，没有治愈或长期有效的治疗方法。的最新进展 遗传技术已经激发了对截短的肌营养不良蛋白的基于基因的治疗恢复的热情， DMD的治疗方法对于DMD患者，几项外显子跳跃临床试验研究正在进行中， 概念体细胞基因编辑研究提供了在动物模型中有效性的证据。迄今为止， 这些努力已经成功地转化为对DMD患者的临床疗效。我们发现体内稳定性降低 内部截短的肌营养不良蛋白的存在是最终临床疗效的显著障碍。我们提供初步的 有证据表明截短的抗肌萎缩蛋白在体内是高度不稳定的，其周转率明显快于完整的抗肌萎缩蛋白。 长度肌营养不良蛋白。预期截短的抗肌萎缩蛋白的稳定性降低对以下方面具有重要意义： 通过对体内治疗作用持续时间产生负面影响而影响长期临床成功。此外，治疗剂 用截短的抗肌萎缩蛋白分子赋予显著的心脏保护作用的表达阈值尚不清楚 截短的抗肌萎缩蛋白只能使抗肌萎缩蛋白缺陷的心脏部分恢复生理功能 in vivo.我们已经建立了一种概念验证方法，以直接确定稳定性和生理 体内心脏中截短的肌营养不良蛋白的表达阈值。指导假设：临床设计的基因 因此，基因编辑的或外显子跳过的截短的抗肌萎缩蛋白分子在治疗中将具有显著更短的半衰期。 与完整的全长抗肌萎缩蛋白相比，在体内心脏中，损害了作用效果的持续时间。具体 目的是建立临床相关的截短的肌营养不良蛋白在营养不良性巨噬细胞中的体内稳定性/半衰期。 心这些知识对于DMD基因临床试验的成功至关重要。这些研究将 对该领域的持久影响，阐明了长期- 目前和未来DMD患者基因治疗的长期有效性。