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.

摘要 癫痫猝死是癫痫最常见的致死原因。没有 预报器和无药可治。先前的研究表明，呼吸异常会导致SUDEP，但 潜在的分子机制或涉及的大脑区域还不是很清楚。此外，也没有 以发病机制为基础的治疗。更好地了解分子、细胞和脑回路缺陷 这会导致癫痫患者的呼吸功能障碍，并可通过药物靶向预防或减少 因此，迫切需要SUDEP。 拟议的研究将结合两个PI在呼吸调节(CRONE)和 癫痫(Gross)验证前脑PI3K/mTOR信号改变导致异常的假设 杏仁核功能，直接通过杏仁核中PI3K/mTOR活性增加或间接通过改变 大脑回路，这会导致呼吸障碍，增加SUDEP的风险。这一假说得到了 初步数据显示，PI3K/mTOR的负调控因子PTEN缺失的小鼠模型 兴奋性前脑神经元存在明显的呼吸障碍，部分抑制PI3K 活动可降低这些小鼠的死亡率。为了进一步检验这一假设，这项拨款提案将利用 两个实验室在PI3K/mTOR信号方面的专业知识及其执行连续和 小鼠隔膜肌电/皮层脑电/视频同步记录提供了一种新的强有力的工具 在较长时间内同时评估呼吸和癫痫发作。目标一号将决定是否呼吸 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。症状前和有症状的患者将在几周内监测呼吸和脑电活动 以评估小鼠呼吸衰竭和癫痫发作的时间和发展。将使用病毒方法 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 在这个小鼠模型中出现异常和猝死。AIM 2还将使用病毒方法和连续 监测呼吸和脑电以测试是否局部增加兴奋性神经元中的PI3K/mTOR信号 杏仁核或海马体足以引起呼吸衰竭、癫痫发作和/或SUDEP。这项研究 将促进对癫痫中PI3K/mTOR信号缺陷的功能后果的了解， 这将有助于揭示导致SUDEP的呼吸缺陷所涉及的大脑电路和分子机制。 此外，它将为开发针对潜在疾病的SUDEP的新治疗策略铺平道路 机制。