Treatment with Gutamate Uptake Enhancers

描述(由申请人提供)： 大量证据表明，谷氨酸毒性是肌萎缩侧索硬化症(ALS)运动神经元损伤的一个重要因素，无论是作为原发事件还是次要事件。兴奋性毒性在肌萎缩侧索硬化症中起重要作用，其机制是：(A)谷氨酸摄取减少导致谷氨酸水平升高，或(B)谷氨酸敏感性增加(如谷氨酸受体改变)。防止兴奋性毒性，例如通过增加细胞从突触间隙运输谷氨酸的能力，应该对ALS有利。我们已经开发了一种基于细胞的分析来筛选增加谷氨酸摄取的分子。使用这种测试，我们最近筛选了1,040种FDA批准的药物的定制集合，发现8种阳性结果在体外持续增加谷氨酸的摄取。我们现在建议在小鼠体内的二次筛选中验证这八种有效药物，并在ALS的小鼠模型上测试这些药物作为治疗该疾病的候选药物。这项研究将以下列目标展开： 1)表征正性HITS对体内谷氨酸转运系统的影响。 2)验证在测量突触体谷氨酸摄取的二级筛查中的阳性命中 由对照组小鼠慢性治疗后给予有效药物治疗。 3)在SOD1-G93A转基因ALS小鼠模型上进行谷氨酸摄取促进剂的试验。该项目的最终目标是在ALS患者的临床试验中测试在小鼠试验中有效的药物。

DESCRIPTION (provided by applicant): A considerable body of evidence implicates glutamate toxicity as a factor that contributes significantly to motor neuron injury, either as a primary or secondary event, in amyotrophic lateral sclerosis (ALS). Excitotoxicity has been suggested to be important in ALS, mediated by (a) increased glutamate levels that are a consequence of reduced glutamate uptake or (b) increased sensitivity to glutamate (e.g. altered glutamate receptors). Preventing excitotoxicity, for example by increasing the capacity of the cells to transport glutamate from the synaptic cleft, should be beneficial in ALS. We have developed a cell-based assay to screen for molecules that increase glutamate uptake. Using this assay, we recently screened a custom collection of 1,040 FDA-approved drugs and found eight positive hits that consistently augment glutamate uptake in vitro. We now propose to validate these eight effective drugs in a secondary screen in vivo in mice, and to test the hits in a mouse model of ALS as therapeutic candidates for the treatment of the disease. The study will be developed in the following aims: 1) Characterize the effect of the positive hits on the glutamate transport system in vivo. 2) Validate the positive hits in a secondary screen measuring glutamate uptake in synaptosomes from control mice after chronic treatment with the effective drugs. 3) Conduct a trial of the glutamate uptake enhancing compounds in SOD1-G93A transgenic mouse model of ALS. The ultimate goal of this project is to test the drugs effective in the mouse trail in a clinical trial for ALS patients.