Na Channel beta4 as a Gene Therapy Target for Epilepsy

描述(由申请人提供)：局灶性发作的癫痫，如颞叶癫痫(TLE)，是一组影响全球数百万人的衰弱疾病。尽管这个问题很大，但TLE的药物治疗在大多数情况下都失败了。40多年来，这些患者剩下的唯一选择就是手术切除颞叶。因此，能够预防局灶性癫痫发作的新型治疗方法的发展将对许多癫痫患者的生活质量产生重大影响。指导这项R21授权的假设是，沉默内嗅皮层(EC)中的过度活跃神经元将防止癫痫发作。在动物模型和人类患者中都有大量证据表明EC神经元在TLE癫痫发作中的作用。初步数据显示，在TLE啮齿动物模型中，由于后去极化电流的增加和Na通道亚单位的表达，EC神经元的放电增加。假说是，使用短发夹状RNA(ShRNA)下调Na通道β-4亚单位的表达将减少癫痫发作。重组腺相关病毒(RAAV)已成为人类基因治疗的首选。一个重要的安全特征是能够规范基因治疗。这将使用新开发的四环素调节盒来完成，该盒控制shRNA的表达并需要药物来激活(多西环素-ON)。总体目标是开发一种可用于临床的shRNA递送系统，并在TLE动物模型中测试其疗效。

DESCRIPTION (provided by applicant): Seizures with a focal onset, such as temporal lobe epilepsy (TLE), are a set of debilitating disorders that affect millions of people worldwide. Despite the size of this problem, medical treatment of TLE fails in most cases. For over 40 years, the only option left for these patients has been surgery to remove the temporal lobe. Therefore, the development of novel treatments that can prevent focal seizures will have a significant impact on the quality of life of many epilepsy patients. The hypothesis guiding this R21 grant is that silencing hyperactive neurons in the Entorhinal Cortex (EC) will prevent seizures. Substantial evidence in both animal models and human patients incriminate the role of EC neurons in TLE seizures. Preliminary data show that in rodent models of TLE, EC neurons have increased firing due to increased after-depolarizing currents and increased expression of Na channel subunits. The hypothesis is that knocking down the expression of the Na channel beta-4 subunit using short-hairpinned RNA (shRNA) will reduce seizures. Recombinant adeno-associated virus (rAAV) has emerged as the top choice for human gene therapy. An important safety feature is the ability to regulate gene therapy. This will be accomplished using a newly developed tetracycline regulator cassette that controls expression of the shRNA and requires drug for activation (doxycycline-ON). The overall goal is to develop a delivery system for the shRNA that can be used in the clinic and to test its efficacy in animal models of TLE.