Investigating the role of brainstem neuroinflammation in cardiorespiratory control in a rat model of recurrent epilepsy

研究脑干神经炎症在复发性癫痫大鼠模型心肺控制中的作用

• 批准号: 10462194
• 负责人: Wasif A Osmani
• 金额: $ 4.88万
• 依托单位: MEDICAL COLLEGE OF WISCONSIN
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-07-01 至 2025-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10462194
• 关键词: Address; Affect; Animal Model; Antiepileptic Agents; Apnea; Astrocytes; BLR1 gene; Baroreflex; Bioinformatics; Biological Assay; Brain; Brain Stem; Brain region; Breathing; CCL2 gene; CXCL13 gene; Cause of Death; Cell Nucleus; Cells; Cessation of life; Chemoreceptors; Chronic; Complex; DNA Sequence Alteration; Data; Epilepsy; Event; Exons; Exposure to; Failure; Fellowship; Female; Functional disorder; Gene Expression; Gene Expression Profile; Generations; Genes; Glial Fibrillary Acidic Protein; Goals; Health; Heart Arrest; Heart Rate; Hippocampus (Brain); Human; Impairment; Individual; Inflammatory; Interleukin-1; Interleukin-1 beta; Intervention; Intractable Epilepsy; Knock-out; Knowledge; Lead; Life; Ligands; Mediating; Mediator of activation protein; Medical; Microglia; Modeling; Molecular; Monitor; Morphology; Nerve Degeneration; Neurologic; Neuronal Dysfunction; Neurons; Nuclear RNA; Nucleus solitarius; PTGS2 gene; Pathologic; Pathway Analysis; Pathway interactions; Patients; Pattern; Peptide Hydrolases; Persons; Pharmacology; Play; Potassium Channel; Prevention; Proteins; Protocols documentation; Publishing; Rattus; Recurrence; Respiratory physiology; Risk; Rodent Model; Role; Seizures; Serotonin; Signal Pathway; Signal Transduction; Small Nuclear RNA; System; Testing; Tissue-Specific Gene Expression; Tissues; Tonic - clonic seizures; audiogenic seizure; base; cell type; chemokine; chemokine receptor; cytokine; experience; experimental study; high risk; human data; inward rectifier potassium channel; male; mortality; neural circuit; neural network; neuroinflammation; new therapeutic target; novel; patient population; prevent; raphe nuclei; respiratory; sound; sudden unexpected death in epilepsy; transcriptome sequencing; transcriptomics; zinc finger nuclease

Abstract: Epilepsy is one of the most common neurological conditions in the world. Treatment with anti-epileptic drugs (AEDs) prevent recurrent seizures in ~70% of patients with epilepsy, but the remaining 30% of patients with refractory epilepsies continue to experience uncontrolled seizures. The negative consequences of repeated seizures include post-ictal cardiorespiratory suppression putting these patients at high risk of Sudden Unexpected Death in Epilepsy (SUDEP). Fundamental knowledge gaps exist in our understanding of how repeated seizures disrupt the vital cardiorespiratory control systems in the brain. A factor commonly identified in many neurological conditions including epilepsy is neuroinflammation, which supports beneficial functions in health but is dysregulated in epilepsy patients and animal models of seizure disorder. Key cells within the CNS mediating pathological neuroinflammation are resident microglia and astrocytes, which have also been shown to be dysfunctional in human epilepsy. However, it is not known what mechanistic role the glial-derived neuroinflammation plays in the impairment of cardiorespiratory control or increased SUDEP risk. Here, I hypothesize that repeated seizures lead to activation of neuroinflammation mediated by microglia within key brainstem regions controlling cardiorespiratory function causing a progressive decline in these vital functions. Published and preliminary data in our novel rat model with genetic mutations in a gene (kcnj16) encoding an inwardly-rectifying potassium ion channel (Kir5.1; SSkcnj16-/- rats) show that repeated sound-induced seizures (1/day for up to 10 days) lead to progressively more severe post-ictal cardiorespiratory suppression and unexpected mortality particularly in male rats. Through snRNA sequencing and bioinformatic pathway analyses of transcriptomic changes specifically within microglial cells in the medullary raphe (key breathing control region) identified significant predicted activation of IL-1ß signaling following repeated seizures, consistent with immunofluorescent brainstem tissue analyses. Here I propose two Specific Aims which: 1) characterize cell- specific transcriptomic shifts in gene expression within key cardiorespiratory control regions to identify key cells types and pathways mediating local neuroinflammation leading to neuronal dysfunction, and 2) functionally test the roles of microglia and IL-1 signaling in the brain in mediating the progressive cardiorespiratory suppression and/or unexpected seizure-induced mortality. Identifying neuroinflammatory signals/pathways induced by repeated seizures within distinct neural circuits in our novel rat model will enhance our understanding of the pathophysiological consequences of uncontrolled seizures in patients with refractory epilepsy, and hold the potential for identifying new therapeutic targets aimed at preventing seizure-induced cardiorespiratory dysfunction function and reduce SUDEP risk.

翻译后摘要：癫痫是世界上最常见的神经系统疾病之一。抗癫痫治疗 抗癫痫药物（AEDs）可预防约70%的癫痫患者复发，但其余30%的患者 难治性癫痫患者继续经历不受控制的癫痫发作。重复的负面影响 癫痫发作包括发作后心肺抑制，使这些患者处于突发性高风险中。 癫痫意外死亡（SUDEP）在我们对如何理解的理解中存在着基本的知识差距 反复发作会破坏大脑中至关重要的心肺控制系统。一个常见的因素， 包括癫痫在内的许多神经系统疾病都是神经炎症，它支持神经系统的有益功能， 健康，但在癫痫患者和癫痫发作障碍的动物模型中失调。CNS内的关键细胞 介导病理性神经炎症的是常驻的小胶质细胞和星形胶质细胞， 在人类癫痫中是功能失调的。然而，目前尚不清楚胶质源性神经胶质细胞的作用机制。 神经炎症在心肺控制受损或SUDEP风险增加中起作用。这里我 假设反复癫痫发作导致内小胶质细胞介导的神经炎症激活， 控制心肺功能的关键脑干区域导致这些重要的 功能协调发展的在我们的新的大鼠模型与基因突变（kcnj 16）发表和初步数据 编码内向整流钾离子通道（Kir5.1; SSkcnj 16-/-大鼠）显示，重复的声音诱导 癫痫发作（1次/天，持续10天）导致发作后心肺抑制逐渐加重， 意外死亡，尤其是雄性大鼠。通过snRNA测序和生物信息学途径分析 转录组学的变化，特别是在小胶质细胞在延髓缝（关键呼吸控制区） 确定了反复癫痫发作后IL-1 β信号传导的显著预测激活，与 免疫荧光脑干组织分析。在这里，我提出了两个具体的目标，其中：1）表征细胞- 关键心肺控制区域内基因表达的特异性转录组变化，以识别关键细胞 类型和途径介导局部神经炎症导致神经元功能障碍，和2）功能测试 脑内小胶质细胞和IL-1信号在介导进行性心肺抑制中的作用 和/或意外的死亡率。识别由以下物质诱导的神经炎症信号/通路 在我们的新型大鼠模型中，不同神经回路内的反复癫痫发作将增强我们对癫痫的理解。 难治性癫痫患者不受控制的癫痫发作的病理生理学后果，并保持 确定新的治疗靶点以预防糖尿病诱导的心肺功能障碍的可能性 降低SUDEP风险。