Assessing the contribution of altered PI3K signaling to breathing abnormalities and sudden death in epilepsy

评估 PI3K 信号传导改变对癫痫呼吸异常和猝死的影响

• 批准号: 10458153
• 负责人: STEVEN ALLEN CRONE
• 金额: $ 19.88万
• 依托单位: CINCINNATI CHILDRENS HOSP MED CTR
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-02-15 至 2024-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10458153
• 关键词: Acute; Affect; Amygdaloid structure; Animals; Apnea; Applications Grants; Area; Brain; Brain Stem; Brain region; Breathing; Cardiovascular system; Cells; Chronic; Cortical Malformation; Data; Defect; Development; Disease; Electroencephalography; Epilepsy; FRAP1 gene; Family; Functional disorder; Future; Germ-Line Mutation; Goals; Hippocampus (Brain); Human; Incidence; Individual; Knock-out; Knockout Mice; Knowledge; Laboratories; Lesion; Measures; Mediating; Medical; Methods; Modeling; Molecular; Monitor; Mus; Neurons; PTEN gene; Pathway interactions; Persons; Pharmacologic Substance; Phosphatidylinositols; Phosphotransferases; Play; Prosencephalon; Public Health; Publishing; Recurrence; Regulation; Research; Respiratory Diaphragm; Risk; Role; Seizures; Severities; Signal Pathway; Signal Transduction; Somatic Mutation; Sudden Death; Testing; Time; United States; Video Recording; Viral; Work; base; brain circuitry; dentate gyrus; designer receptors exclusively activated by designer drugs; diphtheria toxin receptor; excitatory neuron; high risk; human model; mortality; mouse model; novel; prevent; respiratory; sudden unexpected death in epilepsy; tool; treatment strategy

SUMMARY Sudden unexpected death in epilepsy (SUDEP) is the most frequent cause of mortality in epilepsy. There are no predictors and no cures. Previous research suggests that breathing abnormalities contribute to SUDEP, but the underlying molecular mechanisms or brain areas involved are not well understood. Moreover, there are no disease mechanism-based treatments. A better knowledge of the molecular, cellular and brain circuit defects that contribute to respiratory deficits in epilepsy and that could be pharmaceutically targeted to prevent or reduce SUDEP is therefore urgently needed. The proposed research will combine the synergistic expertise of two PIs in respiratory regulation (Crone) and epilepsy (Gross) to test the hypothesis that altered PI3K/mTOR signaling in the forebrain causes aberrant amygdala function, either directly through increased PI3K/mTOR activity in the amygdala or indirectly via altered brain circuits, which leads to breathing deficits that increase the risk for SUDEP. The hypothesis is supported by preliminary data showing that a mouse model with a deletion of PTEN, a negative regulator of the PI3K/mTOR pathway, in excitatory forebrain neurons has prominent breathing deficits, and that partial inhibition of PI3K activity reduces mortality in these mice. To further test this hypothesis, this grant proposal will take advantage of the two laboratories’ expertise in PI3K/mTOR signaling and their capability to perform continuous and synchronized diaphragm EMG/cortical EEG/video recording in mice, which provides a novel and powerful tool to simultaneously assess breathing and seizures for extended periods of time. Aim 1 will determine if breathing abnormalities in forebrain-specific Pten knockout mice are dependent on amygdala function and/or seizure activity. Breathing and EEG activity will be monitored over several weeks in presymptomatic and symptomatic mice to evaluate the timing and development of respiratory deficits and seizures. Viral approaches will be used to silence or ablate excitatory neurons in the amygdala to test if amygdala activity is necessary for breathing abnormalities and sudden death in this mouse model. Aim 2 will also use viral approaches and continuous monitoring of breathing and EEG to test if locally increasing PI3K/mTOR signaling in excitatiory neurons of the amygdala or the hippocampus is sufficient to cause respiratory deficits, seizures and/or SUDEP. This research will advance the knowledge about the functional consequences of defective PI3K/mTOR signaling in epilepsy, and will help reveal the brain circuits and molecular mechanisms involved in respiratory deficits causing SUDEP. Further, it will pave the way to develop novel treatment strategies for SUDEP targeting the underlying disease mechanisms.

概括 癫痫猝死（SUDEP）是癫痫最常见的死亡原因。 先前的研究表明呼吸异常会导致 SUDEP，但 此外，人们对潜在的分子机制或所涉及的大脑区域还没有很好的了解。 基于疾病机制的治疗方法。更好地了解分子、细胞和脑回路缺陷。 导致癫痫的呼吸缺陷，并且可以通过药物靶向来预防或减少 因此，迫切需要 SUDEP。 拟议的研究将结合两位 PI 在呼吸调节 (Crone) 和 癫痫 (Gross) 检验前脑 PI3K/mTOR 信号传导改变导致异常的假设 杏仁核功能，直接通过增加杏仁核中的 PI3K/mTOR 活性或间接通过 大脑回路，导致呼吸缺陷，增加 SUDEP 的风险。 初步数据显示，缺失 PTEN（PI3K/mTOR 的负调节因子）的小鼠模型 途径，在兴奋性前脑神经元中具有显着的呼吸缺陷，并且部分抑制 PI3K 为了进一步检验这一假设，本拨款提案将利用这些小鼠的活动死亡率降低。 两个实验室在 PI3K/mTOR 信号传导方面的专业知识及其连续和执行的能力 小鼠同步隔膜肌电图/皮质脑电图/视频记录，提供了一种新颖而强大的工具 同时评估长时间的呼吸和癫痫发作，目标 1 将确定是否呼吸。 前脑特异性 Pten 敲除小鼠的异常取决于杏仁核功能和/或癫痫发作 将在症状前和症状期间监测呼吸和脑电图活动。 将使用病毒方法来评估小鼠呼吸缺陷和癫痫发作的时间和发展。 沉默或消融杏仁核中的兴奋性神经元，以测试杏仁核活动是否是呼吸所必需的 该小鼠模型的异常和猝死也将使用病毒方法和连续治疗。 监测呼吸和脑电图，以测试大脑兴奋性神经元中的 PI3K/mTOR 信号是否局部增加 杏仁核或海马体足以引起呼吸缺陷、癫痫发作和/或 SUDEP。 将增进对癫痫中 PI3K/mTOR 信号传导缺陷的功能后果的了解， 并将有助于揭示导致 SUDEP 的呼吸缺陷所涉及的大脑回路和分子机制。 此外，它将为开发针对潜在疾病的 SUDEP 新型治疗策略铺平道路 机制。