A drug-based approach for integrin-mediated alleviation of muscular dystrophy

描述（由申请人提供）：杜氏肌营养不良症（DMD）是一种导致过早死亡的严重肌肉萎缩疾病。目前，这种毁灭性的神经肌肉疾病还没有治愈或有效的治疗方法。17整合素在DMD患者和mdx小鼠模型肌肉中的表达增加。同时缺乏肌营养不良蛋白和17整合素的小鼠表现出严重的肌肉萎缩，并在4周龄前死亡。最近，我们证明了增强骨骼肌中17整合素的转基因表达可以提高营养不良小鼠的生存能力。综上所述，这些研究表明17整合素是DMD患者和mdx小鼠肌肉中的主要遗传修饰因子，并提示上调17整合素基因表达的化合物可能作为DMD的潜在治疗方法。在这项研究中，我们将启动一个小分子发现项目，以确定靶向17整合素基因表达的化合物。我们将使用从转基因小鼠中分离的克隆肌细胞系来开发整合素基因表达的荧光检测系统。该系统将允许在其正常细胞和基因组背景下评估17个整合素启动子的活性。这个以细胞为基础的系统将用已知能增加17个整合素基因表达的化合物进行测试。经过验证的基于细胞的分析将应用于自动化的高通量药物筛选，以鉴定在培养的小鼠肌肉细胞中增加17个整合素基因表达的化合物。阳性化合物将在培养的小鼠和人类肌肉细胞中进行测试，以确定药物的功效、毒性和转化为人类肌肉细胞的能力。总之，这些目标将使我们能够验证小化合物可以增加小鼠和人类肌肉细胞中整合素基因表达的假设。鉴定增加17个整合素基因表达的小化合物将构成未来研究的基础，这将把我们的基础生物医学研究转化为未来人类临床试验的药物开发。项目的叙述

DESCRIPTION (provided by applicant): Duchenne Muscular Dystrophy (DMD) is a severe muscle wasting disease that leads to premature death. Currently, there is no cure or effective treatment for this devastating neuromuscular disease. Expression of the 17 integrin is increased in the muscle of DMD patients and the mdx mouse model. Mice lacking both dystrophin and the 17 integrin exhibit severe muscular dystrophy and die before 4 weeks of age. Recently we demonstrated that enhanced transgenic expression of the 17 integrin in skeletal muscle can increase the viability of dystrophic mice. Together these studies show that the 17 integrin is a major genetic modifier in the muscle of DMD patients and mdx mice and suggest that compounds that up-regulate 17 integrin gene expression may serve as a potential therapy for DMD. In this study we will initiate a small-molecule discovery program to identify compounds that target 17 integrin gene expression. We will use a clonal muscle cell line isolated from transgenic mice to develop a fluorescent assay system for integrin gene expression. This system will allow an assessment of 17 integrin promoter activity in its normal cellular and genomic context. This cell-based system will be tested with compounds known to increase 17 integrin gene expression. The validated cell-based assay will then be applied to an automated high throughput drug screen to identify compounds that increase 17 integrin gene expression in cultured mouse muscle cells. Positive compounds will be tested in cultured murine and human muscle cells to determine drug efficacy, toxicity and ability to translate to human muscle cells. Together these aims will allow us to test the hypothesis that small compounds can increase 17 integrin gene expression in murine and human muscle cells. The identification of small compounds that increase 17 integrin gene expression will form the basis of future studies which will translate our basic biomedical research studies to the development of drugs for future human clinical trails.Project Narrative Duchenne Muscular Dystrophy is a devastating muscle disease that affects nearly 50,000 children in the United States. Increased expression of 17 integrin has been shown to be enormously beneficial to mouse models for this disease. This study aims to identify drugs that increase 17 integrin gene expression which may prove to be of therapeutic value to patients that suffer from DMD.