The Role of Raptor in Temporal Lobe Eplieptogenesis

猛禽在颞叶表皮发生中的作用

• 批准号: 10299626
• 负责人: Christin Margaret Godale
• 金额: $ 3.94万
• 依托单位: CINCINNATI CHILDRENS HOSP MED CTR
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-12-01 至 2022-06-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10299626
• 关键词: Adaptor Signaling Protein; Advocate; Affect; Animal Model; Animals; Antiepileptic Agents; Antiepileptogenic; Axon; Brain; Cell physiology; Cells; Cellular Metabolic Process; Cellular Morphology; Complex; Development; Disease; Doctor of Philosophy; Electrodes; Epilepsy; Epileptogenesis; Exhibits; FRAP1 gene; Foundations; Frequencies; Genetic; Genetic Recombination; Growth; Hippocampus (Brain); Homeostasis; Hypertrophy; Implant; Incidence; Individual; Injections; Intractable Epilepsy; Lead; Measurable; Mediating; Medical; Mentors; Metabolic; Methodology; Modeling; Morphology; Mus; Neuronal Plasticity; Neurons; Newborn Infant; PTEN gene; Pathogenesis; Pathologic; Pathology; Pathway interactions; Patients; Persons; Pharmacology; Pilocarpine; Play; Positioning Attribute; Raptors; Recurrence; Research; Risk; Rodent; Role; Seizures; Severities; Signal Pathway; Signal Transduction; Sirolimus; Status Epilepticus; Temporal Lobe; Temporal Lobe Epilepsy; Testing; Training; Transgenic Animals; United States; Viral; Virus; antagonist; calmodulin-dependent protein kinase II; career; cellular targeting; dentate gyrus; effective therapy; entorhinal cortex; experience; granule cell; improved; inhibitor; innovation; internal control; molecular drug target; mossy fiber; nervous system disorder; neuronal cell body; neuronal growth; novel; prevent

Project Summary Despite availability of anti-epileptic drugs, one-third of the 3.4 million US patients with epilepsy have medically intractable epilepsy and still experience seizures despite treatment. There are no effective treatments to prevent the development of this debilitating condition (antiepileptogenic) in at-risk patients. The mechanistic target of rapamycin (mTOR) pathway, which regulates neuronal plasticity and growth, has emerged as a promising candidate for the development of anti-epileptogenic therapies. Pharmacological antagonists of the mTOR pathway have shown efficacy at preventing seizure occurrence in animal models of epilepsy, however, the cellular targets and signaling complexes mediating these effects are unclear. Hippocampal dentate granule cells (DGCs) may be prime targets of mTOR mediated pathological changes seen in temporal lobe epilepsy (TLE). mTOR signaling is increased among DGCs during the development of TLE, and treatment with rapamycin can block the formation of atypical DGC morphology. Our lab has shown that deletion of mTOR inhibitor, phosphatase and tensin homolog (PTEN) from newborn hippocampal dentate granule cells (DGCs) resulted in the mossy fiber sprouting and soma hypertrophy associated with epilepsy. These abnormalities exhibited in DGCs are thought to be associated with breakdown of the dentate gyrus’ ability to filter incoming information from the entorhinal cortex, creating hyper-excitable hippocampal circuits, resulting in spontaneous recurrent seizures. We hypothesize that rapamycin produces its diseasing modifying effects by blocking mTOR signaling in DGCs. To test this hypothesis, we will genetically delete the essential mTORC1 adaptor protein raptor from granule cells in a mouse TLE model and determine whether the treatment reduces seizure incidence and prevents dysmorphogenesis in DGCs (Aim 1). To assess the role of raptor in epileptogenesis, we have developed a viral strategy in which LoxP-flanked raptor can be deleted after pilocarpine-induced status epilepticus by injecting transgenic animals with AAV9.CamKII.HI.eGFP-Cre. Cre- mediated recombination in hippocampal neurons will lead to the deletion of raptor, preventing mTORC1 activity in these cells. (Aim 2) We predict that blocking hippocampal DGCs plays a role in the pathogenesis of TLE. Our proposal leverages collaborative, conceptual, and methodological innovation to make meaningful progress towards delineating the roles of mTORC1 and mTORC2 in the pathogenesis of epilepsy. The results, together with mentored training, will provide a foundation for working toward new solutions for epilepsy and other neurological disorders.

项目概要 尽管有抗癫痫药物可用，但在 340 万美国癫痫患者中，有三分之一仍需要接受药物治疗 顽固性癫痫，尽管接受治疗但仍会癫痫发作。目前还没有有效的治疗方法 防止高危患者出现这种使人衰弱的疾病（抗癫痫原）。 雷帕霉素 (mTOR) 通路的机制靶点调节神经元可塑性和生长， 成为开发抗癫痫疗法的有希望的候选者。药理作用 mTOR 通路拮抗剂已在动物模型中显示出预防癫痫发作的功效 然而，对于癫痫，介导这些效应的细胞靶点和信号复合物尚不清楚。 海马齿状颗粒细胞 (DGC) 可能是 mTOR 介导的病理变化的主要靶标 见于颞叶癫痫（TLE）。在 DGC 发育过程中，mTOR 信号传导增强 TLE 和雷帕霉素治疗可以阻止非典型 DGC 形态的形成。我们的实验室已经表明 新生儿海马齿状体中 mTOR 抑制剂、磷酸酶和张力蛋白同源物 (PTEN) 的缺失 颗粒细胞（DGC）导致与癫痫相关的苔藓纤维发芽和体细胞肥大。 DGC 中表现出的这些异常被认为与齿状回的故障有关 过滤来自内嗅皮层的传入信息的能力，创建超兴奋的海马回路， 导致自发性反复发作。我们假设雷帕霉素可以改善疾病 通过阻断 DGC 中的 mTOR 信号传导来发挥作用。为了检验这个假设，我们将从基因上删除必需的 来自小鼠 TLE 模型中颗粒细胞的 mTORC1 接头蛋白猛禽，并确定是否 治疗可降低 DGC 的癫痫发作发生率并预防畸形发生（目标 1）。评估的作用 猛禽在癫痫发生过程中，我们开发了一种病毒策略，其中 LoxP 侧翼的猛禽可以在癫痫发生后被删除。 通过给转基因动物注射 AAV9.CamKII.HI.eGFP-Cre 来诱导毛果芸香碱诱发癫痫持续状态。克里- 海马神经元介导的重组将导致 raptor 的缺失，从而阻止 mTORC1 活性 在这些细胞中。 （目标 2）我们预测阻断海马 DGC 在 TLE 的发病机制中发挥作用。 我们的提案利用协作、概念和方法创新来取得有意义的进展 旨在描述 mTORC1 和 mTORC2 在癫痫发病机制中的作用。结果，一起 通过指导培训，将为致力于癫痫和其他疾病的新解决方案奠定基础 神经系统疾病。