Identifying a Role for Vasoactive Intestinal Peptide Expressing Interneurons in a Mouse Model of Dravet Syndrome

鉴定血管活性肠肽表达中间神经元在 Dravet 综合征小鼠模型中的作用

基本信息

批准号：
9907136
负责人：
Kevin Goff
金额：
$ 5万
依托单位：
UNIVERSITY OF PENNSYLVANIA
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-12-01 至 2021-11-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9907136
关键词：
Achievement Action Potentials Acute Affect Age Attention Axon Behavior Brain Calcium Cells Childhood Clinical Code Cognitive Complex Confocal Microscopy Data Development Disease Disease model Disinhibition Electrophysiology (science)Epilepsy ErbB4 gene Exhibits Experimental Models Fellowship Foundations Functional disorder Future Gene Expression Generations Genes Genetic Glutamates Goals Human Image Imaging Techniques Immunohistochemistry Impaired cognition Impairment In Vitro Individual Intellectual functioning disability Interneurons Intractable Epilepsy Ion Channel Ions Learning Link Locomotion Measures Mediating Methods Modeling Molecular Biology Morphology Motor Cortex Mus Mutation National Research Service Awards Neurodevelopmental Disorder Neurologic Neurons Neurosciences Research Parvalbumins Pathogenesis Pharmacology Phenocopy Phenotype Physicians Physiology Positioning Attribute Property Pyramidal Cells Research Role Running Schizophrenia Scientist Seizures Sensory Slice Sodium Sodium Channel Somatosensory Cortex Somatostatin Sudden Death Synapses Syndrome Temperature Testing Therapeutic Therapeutic Intervention Training Translating Vasoactive Intestinal Peptide Wakefulness Whole-Cell Recordings Work autism spectrum disorder autistic awake barrel cortex base career cholinergic design doctoral student dravet syndrome effective therapy experience experimental study functional disability in vivo in vivo calcium imaging in vivo imaging loss of function mutation mouse model neuroregulation novel optogenetics outcome forecast pre-clinical recruit sensory integration synaptogenesis targeted treatment translational neuroscience two-photon voltage

项目摘要

PROJECT SUMMARY: I am applying for this NRSA fellowship as an MD/PhD student with the long-term goal of becoming a successful physician scientist running my own translational neuroscience research lab. This project is designed to give me the training and experience required towards achievement of this goal. The goal of the project is to investigate the mechanisms of epilepsy and cognitive impairment in Dravet syndrome. Dravet syndrome is a severe neurodevelopmental disorder of childhood defined by epilepsy and autism that is currently without cure or disease-modifying therapy. This syndrome is caused by mutations in the gene SCN1A, which codes for the voltage gated sodium channel alpha subunit Nav1.1. Based on work in a mouse model of Dravet Syndrome, it is hypothesized that GABAergic interneurons – particularly the subsets marked by expression of parvalbumin (PV-INs) and somatostatin (SST-INs) – are selectively impaired, while excitatory glutamatergic neurons are not affected. Interneurons are classically considered to be inhibitory, so loss of Nav1.1 in interneurons is thought to cause decreased inhibition in the developing brain with resulting cognitive impairment and epilepsy. However, interneurons are incredibly diverse in terms of gene expression, morphology, electrophysiological properties, and synaptic connectivity. Interneurons marked by expression of vasoactive intestinal peptide (VIP-INs) constitute a third prominent subset of interneurons that form distinct disinhibitory circuits by primarily targeting other interneurons, and thereby regulate cognitive processing, attention, and learning, functions which are impaired in Dravet Syndrome. However, no previous study has investigated whether VIP-INs are impaired in this model. I show preliminary data indicating that VIP-INs do express Nav1.1 and have impaired excitability in a mouse model of Dravet Syndrome. I hypothesize that this leads to dysfunction of disinhibitory microcircuits that underlie sensory processing and brain state modulation. In Aim1, I use slice electrophysiology, immunohistochemistry, and pharmacology to show that VIP-INs in fact express Nav1.1 and are functionally impaired in Dravet syndrome mice. In Aim 2, I will investigate the effect of VIP interneuron dysfunction on the activity of a specific sensorimotor circuit in Dravet Syndrome mice using optogenetics and synaptic physiology. Finally, in Aim 3, I will use two-photon calcium imaging to study cortical dynamics that depend on VIP-IN activity in awake behaving DS mice in vivo. Results will implicate VIP-IN dysfunction in the pathogenesis of Dravet syndrome and suggest novel avenues for therapy.

项目概要：我正在以医学博士/博士生的身份申请 NRSA 奖学金，其长期目标是成为一名成功的人经营我自己的转化神经科学研究实验室的医师科学家该项目旨在为我提供帮助。实现这一目标所需的培训和经验。该项目的目标是研究 Dravet 癫痫和认知障碍的机制 Dravet 综合征是一种严重的儿童神经发育障碍，定义为癫痫和目前尚无治愈或疾病缓解疗法的自闭症，这种综合症是由基因突变引起的。基因 SCN1A，编码电压门控钠通道 α 亚基 Nav1.1。 Dravet 综合征小鼠模型，重新认识到 GABA 能中间神经元 – 特别是子集以小清蛋白 (PV-IN) 和生长抑素 (SST-IN) 的表达为标志 - 选择性受损，而兴奋性谷氨酸能神经元不受影响，因此中间神经元通常被认为是抑制性的。中间神经元中 Nav1.1 的缺失被认为会导致发育中大脑的抑制作用降低，从而导致然而，中间神经元在基因表达方面极其多样化。形态、电生理学特性和突触连接通过表达来标记。血管活性肠肽（VIP-IN）构成中间神经元的第三个重要子集，形成独特的中间神经元主要针对其他中间神经元来抑制电路，并由此调节认知处理， Dravet 综合症患者的注意力和学习功能会受到损害，但之前还没有研究表明。调查了 VIP-IN 在此模型中是否受到损害，我展示了表明 VIP-IN 确实受到损害的初步数据。在 Dravet 综合征小鼠模型中表达 Nav1.1 且兴奋性受损。导致感觉处理和大脑状态调节基础的去抑制微电路功能障碍。 Aim1，我使用切片电生理学、免疫组织化学和药理学来证明 VIP-IN 实际上在 Dravet 综合征小鼠中表达 Nav1.1 且功能受损。在目标 2 中，我将研究 Nav1.1 的影响。 VIP 中间神经元功能障碍对 Dravet 综合征小鼠特定感觉运动回路活性的影响最后，在目标 3 中，我将使用双光子钙成像来研究皮质。依赖于 DS 小鼠体内清醒行为的 VIP-IN 活性的动态结果将暗示 VIP-IN。 Dravet 综合征发病机制中的功能障碍并提出了新的治疗途径。