Molecular Tweezers: Potential Tools and Therapy for Amyotrophic Lateral Sclerosis

描述(申请人提供)：肌萎缩侧索硬化症(ALS)是一种不可治愈的神经退行性疾病，特征是进行性运动神经元丢失，以散发性和家族性形式发生，并在症状出现后2-5年内导致瘫痪和最终死亡。目前，还没有治疗肌萎缩侧索硬化症的有效方法。尽管ALS的潜在致病机制尚不清楚，但蛋白质聚集被认为是运动神经元死亡和随后疾病进展的主要贡献者。在这种背景下，最具代表性的系统是将铜/锌超氧化物歧化酶1(SOD1)组装成神经毒性低聚物和聚集体。这项拟议的研究将调查新发现的被称为“分子镊子”(MTS)的化合物在细胞培养和表达ALS相关突变体SOD1-G93A的转基因小鼠模型中的作用。预期的结果既是加强对蛋白质聚集在ALS中作用的理解，也是为新的MTS建立结构-活性关系(SAR)，从而开发这些化合物用于ALS的疾病修改治疗。MTS是由Bitan实验室开发的，作为淀粉样蛋白自组装和毒性的广谱、“过程特异性”抑制剂。初步的体外数据显示，一种名为CLR01的先导MT抑制了野生型和突变型SOD1的聚集，并解离了预先形成的SOD1纤维。在与Bitan小组的合作中，Wiedau-Pazos实验室发现CLR01可以减轻表达SOD1-G93A变体的神经细胞系中的细胞死亡。这些初步数据表明，MTS可能通过抑制SOD1的异常聚集而对ALS的运动神经元死亡具有保护作用。基于这些数据，我建议在体外和细胞培养中检测新的MT衍生物，以建立关键离子基团的SAR，并通过在表达SOD1-G93A的小鼠模型中评估其对寿命、肌肉力量和神经病理的影响来测试最有希望的衍生物的疾病修改潜力。

DESCRIPTION (provided by applicant): Amyotrophic lateral sclerosis (ALS) is an incurable, neurodegenerative disease characterized by progressive motor neuron loss, occurring in both sporadic and familial forms and leading to paralysis and ultimately death within 2-5 years after symptom onset. Currently, there are no effective treatments for ALS. Although the underlying pathogenic mechanisms of ALS remain unclear, protein aggregation is believed to be a major contributor to motor neuron death and subsequent disease progression. In this context, the most well- characterized system has been the assembly of Cu/Zn-superoxide dismutase 1 (SOD1) into neurotoxic oligomers and aggregates. The proposed study will investigate the effect of novel, recently-identified compounds called "molecular tweezers" (MTs) in cell culture and in a transgenic mouse model expressing the ALS-associated mutant, SOD1-G93A.The expected outcome is both enhanced understanding of the role of protein aggregation in ALS and establishing structure-activity relationships (SAR) for new MTs towards development of these compounds for disease-modifying therapy for ALS. MTs have been developed by the Bitan Laboratory as broad-spectrum, "process-specific" inhibitors of amyloidogenic proteins' self-assembly and toxicity. Initial in vitro data show that a lead MT called CLR01 inhibits both wild type and mutant SOD1 aggregation and dissociates pre-formed SOD1 fibrils. In collaboration with the Bitan group, the Wiedau-Pazos Laboratory found that CLR01 attenuates cell death in a neuronal cell line expressing the SOD1-G93A variant. These initial data suggest that MTs may be protective against motor neuron death in ALS via inhibition of aberrant aggregation of SOD1. Based on these data, I propose to examine novel MT derivatives in vitro and in cell culture to establish SAR of the key ionic groups and test the disease-modifying potential of the most promising derivative by evaluating its effect on life span, muscle strength, and neuropathology in a mouse model expressing SOD1-G93A.