Molecular Signatures of Amyotrophic Lateral Sclerosis in Skeletal Muscle

描述(申请人提供)：肌萎缩侧索硬化症(ALS)是一种运动神经元退行性疾病，不可抗拒地导致进行性虚弱和死亡。这种疾病没有特定的生物标志物，由于临床和电生理检查在早期阶段往往不确定，因此诊断往往被推迟。此外，一旦确诊，目前跟踪患者的工具对于及时检测疾病的改善或恶化是不敏感的。一种可以促进诊断、跟踪疾病进展或两者兼而有之的生物标记物，将填补ALS治疗方面的一大临床空白，并加快新疗法的临床试验。这项应用的长期目标是识别分子 肌萎缩侧索硬化症患者肌肉中可作为疾病生物标志物的信号。在肌萎缩侧索硬化症中，骨骼肌在运动神经元死亡和临床发作之前就会发生变化，如神经肌肉连接的结构变化，肌肉限制性线粒体功能障碍和纤维萎缩。肌肉是肌萎缩侧索硬化症退变过程中受其影响的“末梢器官”，也是分子研究中最容易接触到的。在这里，我们假设ALS患者肌肉中的基因表达模式包含可以作为疾病生物标记物的分子签名。这一假设是基于我们对临床特征良好的ALS患者的肌肉样本进行下一代深度测序获得的初步数据。使用非肌萎缩侧索硬化症和正常对照样本，我们在肌萎缩侧索硬化症样本中确定了300多个独特的靶点，包括异构体变异，这将作为这一应用研究的基础。我们非常适合进行这项研究，因为包括肌萎缩侧索硬化症和肌萎缩侧索硬化症模拟患者在内的大量神经肌肉患者，以及我们对电诊断和肌肉组织学实验室的监督。在这里，我们将以以下两个具体目标进一步研究我们的分子靶点：具体目标：1.通过对大量ALS和非ALS肌肉样本进行PCR分析，验证通过深度测序确定的ALS特异性靶点和同工型差异。2：评估ALS患者肌肉组织中有效靶点的蛋白表达，并将其与G93A SOD1ALS小鼠的肌肉样本相关联。

DESCRIPTION (provided by applicant): Amyotrophic lateral sclerosis (ALS) is a degenerative disease of motor neurons that inexorably leads to progressive weakness and death. There is no specific biomarker for this disease, and the diagnosis is often delayed as clinical and electrophysiological examinations are often inconclusive in the early stages. Furthermore, once a diagnosis is established, the current tools to track patients are insensitive for the timely detection of disease improvement or worsening. A biomarker that can facilitate diagnosis, track disease progression, or both, would fill a large clinical gap in ALS management, and expedite clinical trials of novel therapies. The long term goal of this application is to identify molecular signatures in muscle of ALS patients that can serve as disease biomarkers. In ALS, changes occur in skeletal muscle prior to motor neuron death and clinical onset, such as structural changes in the neuromuscular junction, muscle restricted mitochondrial dysfunction, and fiber atrophy. Muscle is the "end organ" affected by the degenerative process of ALS and is the most accessible for molecular study. Here we hypothesize that gene expression patterns in muscle from patients with ALS contain molecular signatures that can serve as biomarkers of the disease. This hypothesis is based on preliminary data we obtained using next generation deep sequencing on muscle samples of clinically well characterized ALS patients. Using non-ALS disease- and normal control samples, we identified over 300 unique targets in ALS samples, including isoform variances, that will serve as the basis of study for this application. We are wel positioned to carry out this study because of the large neuromuscular patient population, including ALS and ALS mimics, and our oversight of the electrodiagnostic and muscle histology laboratories. Here, we will further investigate our molecular targets with the following two specific aims: Specific Aims: 1. To validate ALS-specific targets and isoform variances identified by deep sequencing by performing PCR analysis of a large cohort of ALS and non-ALS muscle samples. 2: To assess protein expression of validated targets in muscle tissues from ALS patients and correlate targets with muscle samples from the G93A SOD1 ALS mouse.