Restless Legs Syndrome: Pathophysiology using Btbd9 Conditional Knockout Mice

不宁腿综合症：使用 Btbd9 条件性基因敲除小鼠进行病理生理学研究

基本信息

批准号：
8807951
负责人：
YUQING LI
金额：
$ 33.87万
依托单位：
UNIVERSITY OF FLORIDA
依托单位国家：
美国
项目类别：
财政年份：
2014
资助国家：
美国
起止时间：
2014-04-01 至 2019-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8807951
关键词：
Adult Affect Agonist Amphetamines Animal Model Basal Ganglia Behavior Behavioral Binding Biochemical Biological Assay Body Regions Brain Brain region Cerebellum Cerebral cortex Characteristics Chronic Corpus striatum structure Development Disease Dopamine Dopamine Agonists Dopamine D2 Receptor Dopamine Receptor Dystonia Effectiveness Environment Esthesia Etiology Extrapyramidal Disorder Family Study Functional disorder Funding Genes Genetic Genetic Polymorphism Goals Health High Pressure Liquid Chromatography Hippocampus (Brain)Homeostasis Hyperactive behavior Iron Knock-out Knockout Mice Knowledge Lead Leg Lesion Link Measures Mediating Modeling Molecular Molecular Genetics Motor Movement Disorders Mus Mutant Strains Mice Mutation Nerve Degeneration Neuraxis Neurologic Neuronal Plasticity Other Genetics Oxidopamine Pain Parkinson Disease Pathogenesis Pathway interactions Patients Phenotype Population Proteins Publishing Reporting Research Research Personnel Research Project Grants Restless Legs Syndrome Rodent Role Sensory Skeletal Muscle Sleep Spinal Cord Symptoms Synaptic plasticity System Techniques Testing Thalamic structure Therapeutic Tissues Twin Studies Ubiquitination United States National Institutes of Health Western Blotting Work behavioral response brain tract dopamine D5 receptor dopamine transporter dopaminergic neuron genome wide association study improved in vivo interdisciplinary approach iron deficiency iron metabolism molecular phenotype motor disorder mouse model nervous system disorder neurophysiology novel therapeutics radioligand receptor therapeutic development

项目摘要

DESCRIPTION (provided by applicant): Restless legs syndrome (RLS) is a chronic sleep motor disorder characterized by unpleasant sensations in the legs and an uncontrollable urge to move them for relief. Past pathophysiological studies have associated RLS to the disorder of the central dopaminergic system and iron metabolism. Family and twin studies strongly support a genetic contribution to the pathogenesis of RLS. Tremendous progress has been made recently of uncovering genes linked to RLS. Three independent studies published in the last two years all pointed to the role of BTBD9 in RLS. The function of BTBD9 protein is not known. Current animal models include 6-hydroxydopamine-lesioned rodents, iron deficiency mice, and dopamine receptor 3 knockout mice. The identification of the RLS genes paves the way for making genotypic model of RLS that will be more relevant in elucidating the pathophysiology of RLS and developing therapeutic treatments. The broad, long- term objective of our research is to use both complete and targeted conditional knockout mice to determine: 1) the function of the BTBD9 protein in vivo, and 2) how mutations in the BTBD9 protein can lead to RLS. The specific goal of this application is to generate conditional Btbd9 knockout mice and to use our previously generated complete Btbd9 knockout mice to answer these questions. We hypothesize that that different body regions contribute differently to the pathophysiology and symptomology of RLS. We further hypothesize that mutations in BTBD9 lead to alterations in the central dopaminergic system, in particular the striatal D2 receptor mediated indirect pathway. In turn these striatal alterations will affect plasticity in the basal ganglia, in particuar the striatum and, through intrinsic and downstream effects, other regions such as the spinal cord, leading to unpleasant sensations, an urge to move, and other RLS-like phenotypes. We plan to test our hypothesis with the following Specific Aims. 1) To test the hypothesis that functional alterations in the central nervous system underlie the pathophysiology of RLS, we will generate conditional knockout mice of Btbd9 and analyze for RLS-like behavioral and molecular phenotypes. 2) To test the hypothesis that loss of Btbd9 disrupts the dopaminergic system, we will use Btbd9 complete knockout mice and mice with Btbd9 conditionally knocked out in dopaminergic neurons only, and conduct an extensive and thorough analysis of the dopaminergic system in the striatum and spinal cord. 3) To test the hypothesis that loss of Btbd9 alters neural plasticity in basal ganglia circuitry and the spinal cord, we will perform electrophysiological recordings of the corticostriatal tract of the brain and lumbar section of the spinal cord. The successful completion of the above Specific Aims will help us to determine the function of BTBD9 protein in vivo and how the mutation of BTBD9 causes RLS. The results should significantly increase our understanding of the pathophysiology of RLS, which can ultimately aid the development of therapeutic treatments for RLS patients.

描述（由申请人提供）：不宁腿综合症（RLS）是一种慢性睡眠运动障碍，其特征是腿部感觉不舒服以及无法控制地想要移动腿部以缓解压力。过去的病理生理学研究已将 RLS 与中枢多巴胺能系统和铁代谢紊乱相关。家庭和双胞胎研究强烈支持遗传因素对不宁腿综合征的发病机制的影响。最近在发现与不宁腿综合症相关的基因方面取得了巨大进展。过去两年发表的三项独立研究都指出了 BTBD9 在 RLS 中的作用。 BTBD9 蛋白的功能尚不清楚。目前的动物模型包括6-羟基多巴胺损伤的啮齿动物、缺铁小鼠和多巴胺受体3敲除小鼠。 RLS 基因的鉴定为建立 RLS 基因型模型铺平了道路，该模型将在阐明 RLS 的病理生理学和开发治疗方法方面更加相关。我们研究的广泛、长期目标是使用完全和靶向条件敲除小鼠来确定：1) BTBD9 蛋白的体内功能，以及 2) BTBD9 蛋白的突变如何导致不宁腿综合征。本申请的具体目标是生成条件性 Btbd9 敲除小鼠，并使用我们之前生成的完全 Btbd9 敲除小鼠来回答这些问题。我们假设不同的身体区域对 RLS 的病理生理学和症状学有不同的影响。我们进一步假设 BTBD9 的突变导致中枢多巴胺能系统的改变，特别是纹状体 D2 受体介导的间接途径。反过来，这些纹状体的改变将影响基底神经节的可塑性，特别是纹状体，并通过内在和下游效应影响脊髓等其他区域，导致不愉快的感觉、移动的冲动和其他类似不宁腿综合症的表型。我们计划通过以下具体目标来检验我们的假设。 1) 为了检验中枢神经系统功能改变是 RLS 病理生理学基础的假设，我们将生成 Btbd9 的条件敲除小鼠，并分析 RLS 样行为和分子表型。 2）为了检验Btbd9缺失会破坏多巴胺能系统的假设，我们将使用Btbd9完全敲除小鼠和仅在多巴胺能神经元中条件性敲除Btbd9的小鼠，并对纹状体和脊髓中的多巴胺能系统进行广泛而彻底的分析绳索。 3）为了检验 Btbd9 的缺失会改变基底神经节回路和脊髓的神经可塑性的假设，我们将对大脑的皮质纹状体束和腰部的腰部进行电生理记录脊髓。上述具体目标的顺利完成将有助于我们确定BTBD9蛋白在体内的功能以及BTBD9的突变如何引起RLS。这些结果将显着增加我们对 RLS 病理生理学的理解，最终有助于开发针对 RLS 患者的治疗方法。