Understanding the Etiology of CASK Associated Epileptic Encephalopathy

了解 CASK 相关癫痫性脑病的病因

基本信息

批准号：
10533820
负责人：
Sarika Srivastava
金额：
$ 40.04万
依托单位：
VIRGINIA POLYTECHNIC INST AND ST UNIV
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-04-01 至 2025-12-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10533820
关键词：
APBA1 gene ATP phosphohydrolase Acetates Acute Adult Affect Affinity Chromatography Age Age of Onset American Animal Model Apoptosis Behavioral Biogenesis Biological Assay Biological Markers Brain Brain Diseases CDK6-associated protein p18 Calcium Cells Cessation of life Childhood Clinical Cognitive DNA Sequence Alteration DNA cassette Disease Dopamine Early Infantile Epileptic Encephalopathy Electroencephalography Electrophysiology (science)Endoplasmic Reticulum Energy Metabolism Epilepsy Equilibrium Etiology Exhibits Face Functional disorder Gene Expression General Population Genes Glucose Glutamate Receptor Glutamates Glutaminase Glutamine Goals Growth Hydroxybutyrates Impaired cognition Impairment In Situ Nick-End Labeling Infantile spasms Inhibitory Synapse Intervention Isotopes Ketone Bodies Knockout Mice Label Life Link Literature Mammals Mass Spectrum Analysis Measures Membrane Messenger RNA Metabolic Metabolic Pathway Metabolism Methods Mitochondria Mitochondrial Proteins Modeling Multienzyme Complexes Mus Mutation Myoclonus NADH NMR Spectroscopy Neomycin Neonatal Neuroglia Neurons Neurotransmitters Nicotinamide Mononucleotide Outer Mitochondrial Membrane Oxidative Phosphorylation Pathogenicity Pathway interactions Patients Persons Phenotype Physiology Prognosis Protein Interaction Mapping Proteins Pyruvate Reactive Oxygen Species Recurrence Reflex action Residual state Role SIRT1 gene Scanning Electron Microscopy Sirtuins Slice Spasm Structural defect Structure Synapses Testing Therapeutic Tissues Tracer X-linked intellectual disability behavioral impairment early onset effective therapy epileptic encephalopathies experimental study gamma-Aminobutyric Acid human disease improved in vivo infancy inhibitory neuron innovation male mitochondrial dysfunction mitochondrial membrane mortality mouse model neonatal mice neuron loss neuronal excitability neurophysiology novel novel therapeutic intervention oxidation oxidative damage patch clamp pharmacologic postnatal postsynaptic receptor success synaptic function therapeutic evaluation

项目摘要

PROJECT ABSTRACT Epileptic encephalopathies (EEs) are severe brain disorders of early infantile and childhood age onset characterized by epileptic seizures, abnormal electroencephalogram (EEG), severe cognitive and behavioral impairments that might lead to early death. It is estimated that ~2.9 million Americans live with epilepsy and the mortality rate in people with epilepsy is ~2-3 times higher than the general population. Several genetic mutations associate with EEs including mutations in the X-linked intellectual disability gene CASK that are found in patients with Ohtahara syndrome (OS) and West Syndrome (WS). Constitutive CASK deletion in mammals is incompatible with life and the prognosis of CASK hemizygous male patients remains extremely grim. The precise function of CASK and the potential mechanisms by which CASK mutation produces EE remains obscure. Because the constitutive CASK-/- knockout mice exhibited neonatal lethality, we recently generated a novel mouse model of EE by deleting CASK specifically from the neurons (CASKNKO). We found that CASKNKO mice display severe growth retardation, recurrent tonic spasms, EEG anomalies, and myoclonus beginning postnatal day 17 that leads to death by postnatal day 25. Multiple studies have shown that CASK protein is localized at the mitochondrial membranes. Recently, CASK gene expression was found to be regulated in an NAD+/Sirtuin1 dependent manner in mouse neurons. Moreover, we found that mammalian CASK interacts and co-localizes with mitochondrial proteins, and significantly modulates mitochondrial function and number. Based on the evidences from literature and our findings we hypothesize that CASK plays a role in brain mitochondrial function and metabolism, and is critical for optimum neuronal excitability in vivo. To test this hypothesis, we will examine the brain mitochondrial, metabolic, and electrophysiological functional changes as well as synaptic excitatory/inhibitory balance in the CASKNKO mice. We will further identify the specific domain/s of CASK that interacts with mitochondrial proteins, and determine if SIRT1-dependent mitochondrial biogenesis pathway is dysregulated in the brain of CASKNKO mice. Experiments will be performed before and after the onset of myoclonus to distinguish between a potential cause and consequence relation with the disease. We will also test if pharmacological activation of NAD+/SIRT1 pathway can stimulate mitochondrial biogenesis in the brain and CASK expression in glial cells to rescue EE phenotype in the CASKNKO mice. Success in the proposed project will uncover how loss of neuronal CASK alters mitochondrial and synaptic functions to produce EE. The long-term goal of our project is to use the novel CASKNKO EE mouse model to identify potential disease biomarkers and test therapeutic strategies for clinical intervention.

项目摘要癫痫性脑病（EES）是婴儿早期和儿童年龄发作的严重脑疾病具有癫痫发作，异常脑电图（EEG）的特征，严重的认知和行为可能导致早期死亡的障碍。据估计，约有290万美国人患有癫痫和癫痫患者的死亡率比一般人群高约2-3倍。几个遗传与EES相关的突变，包括X连锁智障基因CASK中的突变在Ohtahara综合征（OS）和West综合征（WS）的患者中发现。构成桶删除哺乳动物与生命不兼容，桶半合为男性患者的预后仍然极为严峻。桶的精确功能以及桶突变产生EE的潜在机制仍然晦涩难懂。因为本构桶桶 - / - 敲除小鼠表现出新生儿致死性，我们最近通过从神经元（Casknko）中删除木桶来生成一种新型EE的小鼠模型。我们发现 Casknko小鼠表现出严重的生长迟钝，复发性曲折，脑电图异常和 Myoclonus开始产后第17天，导致产后第25天死亡。多项研究表明该桶蛋白位于线粒体膜上。最近，发现了桶基因表达在小鼠神经元中以NAD+/sirtuin1的方式调节。而且，我们发现哺乳动物桶相互作用并与线粒体蛋白共定位，并显着调节线粒体功能和数字。根据文学的证据和我们的发现，我们假设桶装在脑线粒体功能和代谢中起作用，对于最佳神经元至关重要体内兴奋性。为了检验这一假设，我们将检查大脑线粒体，代谢和 Casknko小鼠的电生理功能变化以及突触兴奋/抑制平衡。我们将进一步确定与线粒体蛋白相互作用的桶的特定域/s，并确定如果SIRT1依赖性线粒体生物发生途径在Casknko小鼠的大脑中失调。实验将在Myoclonus发作之前和之后进行，以区分电势原因和后果与疾病的关系。我们还将测试药理学是否激活 NAD+/SIRT1途径可以刺激大脑中的线粒体生物发生，而胶质细胞中的cask表达在Casknko小鼠中营救EE表型。拟议项目中的成功将揭示如何损失神经元桶改变线粒体和突触功能以产生EE。我们项目的长期目标是使用新型的Casknko EE小鼠模型来识别潜在的疾病生物标志物和测试治疗临床干预策略。