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.

总结 癫痫猝死（SUDEP）是癫痫患者最常见的死亡原因。没有 预测器和没有治愈。以前的研究表明，呼吸异常有助于SUDEP，但 涉及的潜在分子机制或大脑区域还没有很好地理解。此外，没有 基于疾病机制的治疗。更好地了解分子、细胞和脑回路缺陷 其导致癫痫中的呼吸缺陷，并且可以在药物上靶向预防或减少 因此，迫切需要加强可持续发展方案。 拟议的研究将联合收割机结合两个PI在呼吸调节（Crone）和 癫痫（Gross）来检验前脑中改变的PI 3 K/mTOR信号传导引起异常的 杏仁核功能，直接通过增加杏仁核中的PI 3 K/mTOR活性或间接通过改变杏仁核中的PI 3 K/mTOR活性， 大脑回路，导致呼吸缺陷，增加SUDEP的风险。这一假设得到了 初步数据显示，缺失PTEN（PI 3 K/mTOR的负调节因子）的小鼠模型 在兴奋性前脑神经元中，PI 3 K通路的部分抑制具有显著的呼吸缺陷， 活动降低了这些小鼠的死亡率。为了进一步验证这一假设，这项赠款提案将利用 这两个实验室在PI 3 K/mTOR信号传导方面的专业知识及其进行连续和 同步记录小鼠膈肌肌电/皮层脑电/视频，提供了一种新颖而强大的工具， 同时评估呼吸和癫痫发作的时间延长。目标1将决定呼吸 前脑特异性Pten基因敲除小鼠的异常依赖于杏仁核功能和/或癫痫发作 活动呼吸和EEG活动将在几周内监测， 小鼠，以评估呼吸缺陷和癫痫发作的时间和发展。将使用病毒方法 使杏仁核中的兴奋性神经元沉默或消融，以测试杏仁核的活动是否是呼吸所必需的。 异常和突然死亡。Aim 2还将使用病毒式方法， 监测呼吸和EEG，以测试是否局部增加中枢神经系统兴奋性神经元中的PI 3 K/mTOR信号传导。 杏仁核或海马体的损伤足以引起呼吸缺陷、癫痫发作和/或SUDEP。本研究 将推进关于癫痫中PI 3 K/mTOR信号缺陷的功能后果的知识， 并将有助于揭示涉及呼吸缺陷导致SUDEP的脑回路和分子机制。 此外，它将为开发针对潜在疾病的SUDEP新治疗策略铺平道路 机制等