Altered network and rescue of human neurons derived from individuals with early-onset genetic epilepsy.

Early-onset epileptic encephalopathies are severe disorders often associated with specific genetic mutations. In this context, the CDKL5 deficiency disorder (CDD) is a neurodevelopmental condition characterized by early-onset seizures, intellectual delay, and motor dysfunction. Although crucial for proper brain development, the precise targets of CDKL5 and its relation to patients’ symptoms are still unknown. Here, induced pluripotent stem cells derived from individuals deficient in CDKL5 protein were used to generate neural cells. Proteomic and phosphoproteomic approaches revealed disruption of several pathways, including microtubule-based processes and cytoskeleton organization. While CDD-derived neural progenitor cells have proliferation defects, neurons showed morphological alterations and compromised glutamatergic synaptogenesis. Moreover, the electrical activity of CDD cortical neurons revealed hyperexcitability during development, leading to an overly synchronized network. Many parameters of this hyperactive network were rescued by lead compounds selected from a human high-throughput drug screening platform. Our results enlighten cellular, molecular, and neural network mechanisms of genetic epilepsy that could ultimately promote novel therapeutic opportunities for patients.

早发性癫痫性脑病是严重的疾病，常与特定基因突变相关。在此背景下，细胞周期蛋白依赖性激酶样5（CDKL5）缺乏症（CDD）是一种神经发育疾病，其特征为早发性癫痫发作、智力发育迟缓以及运动功能障碍。尽管CDKL5对大脑的正常发育至关重要，但其精确作用靶点以及与患者症状的关系仍然未知。在此，利用从CDKL5蛋白缺乏个体中获取的诱导多能干细胞来生成神经细胞。蛋白质组学和磷酸化蛋白质组学方法揭示了包括基于微管的过程和细胞骨架组织在内的若干通路受到破坏。虽然CDD来源的神经祖细胞存在增殖缺陷，但神经元表现出形态学改变以及谷氨酸能突触发生受损。此外，CDD皮质神经元的电活动显示在发育过程中过度兴奋，导致网络过度同步。通过从人类高通量药物筛选平台中选取的先导化合物，这种过度活跃网络的许多参数得到了改善。我们的研究结果阐明了遗传性癫痫的细胞、分子和神经网络机制，最终可能为患者带来新的治疗机会。