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.

项目摘要：我正在作为MD/PhD学生申请NRSA奖学金，其长期目标是成为成功身体科学家运行我自己的翻译神经科学研究实验室。这个项目旨在给我实现这一目标所需的培训和经验。该项目的目的是研究Dravet中癫痫和认知障碍的机制综合征。 Dravet综合征是一种严重的儿童时期神经发育障碍，由癫痫和自闭症目前尚无治愈或修改疾病的疗法。该综合征是由突变引起的 Gene SCN1A，编码为电压门控钠通道Alpha亚基NAV1.1。基于 Dravet综合征的小鼠模型，假设GABA能中间神经元 - 尤其是子集由白细胞蛋白（PV-INS）和生长抑素（SST-INS）的表达标记 - 有选择地受损兴奋性谷氨酸能神经元不受影响。中间神经元通常被认为是抑制性的，所以据认为，中间神经元中NAV1.1的损失会导致发育中的大脑抑制下降，从而导致认知障碍和癫痫病。然而，在基因表达方面，中间神经元的多样性非常多样化，形态，电生理特性和突触连通性。以表达为标志的中间神经元血管活性肠肽（VIP-INS）构成了中间神经元的第三个突出子集，形成不同通过主要针对其他神经元的主要抑制电路，从而调节认知处理，注意力和学习功能在Dravet综合征中受到损害。但是，以前没有研究研究了该模型中的VIP-INS是否受损。我显示了初步数据，表明VIP-INS确实 Express Nav1.1，并且在Dravet综合征的鼠标模型中受到了令人兴奋的损害。我假设这是导致感官处理和大脑状态调节基础的抑制性微电路功能障碍。在 AIM1，我使用切片电生理学，免疫组织化学和药理学表明VIP-INS实际上 Express NAV1.1并在Dravet综合征小鼠中功能受损。在AIM 2中，我将研究 VIP间神经元的功能障碍在使用Dravet综合征小鼠中特定的感觉运动电路活性光遗传学和突触生理学。最后，在AIM 3中，我将使用两光子钙成像研究皮质取决于在体内醒着的表现DS小鼠中VIP-IN活动的动力学。结果将隐含贵宾 Dravet综合征发病机理的功能障碍，并提出了治疗的新途径。