Astrocytic mechanisms in a new genetic model of migraine

偏头痛新遗传模型中的星形细胞机制

• 批准号: 9926929
• 负责人: Kevin Christopher Brennan
• 金额: $ 48.28万
• 依托单位: UNIVERSITY OF UTAH
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-07-01 至 2023-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9926929
• 关键词: Affect; Animals; Astrocytes; Auras; Behavior; Binding; Brain; Calcium Signaling; Cells; Characteristics; Classic Migraine; Communication; Complex; Connexin 43; Coupling; Data; Disease; Electrophysiology (science); Event; Family; Functional disorder; Gap Junctions; Genes; Genetic Models; Glutamates; Hemiplegia; Human; Image; Impairment; In Vitro; Inherited; Light; Link; Mediating; Migraine; Modeling; Mus; Mutant Strains Mice; Mutation; Neurons; Pain Disorder; Pathway interactions; Phenotype; Phosphorylation; Photophobia; Population; Potassium; Predisposition; Preparation; Property; Proteins; Resolution; Role; Sensory; Sensory Disorders; Spreading Cortical Depression; Stimulus; Techniques; Testing; Vibrissae; Visual Cortex; Whole-Cell Recordings; Work; awake; base; casein kinase I; cortex mapping; disability; experimental study; extracellular; habituation; in vivo; mouse genetics; mutation carrier; nervous system disorder; neuronal excitability; novel; overexpression; relating to nervous system; release of sequestered calcium ion into cytoplasm; response; reuptake; sensory cortex; sensory mechanism; spreading depression; tool; transmission process; two photon microscopy; uptake; virtual; virus genetics

Migraine affects 12% of the world population, and is one of the leading causes of disability worldwide. Yet surprisingly little is known about the basic features of this disease. We helped develop a new mouse genetic model of migraine, and we now propose to examine its mechanisms. The casein kinase 1 delta (CK1d) mouse expresses a mutation from a family with inherited migraine with aura. We found that CK1d mice had two key phenotypes relevant to migraine: an increased sensory network response to a migraine trigger, and an increased susceptibility to cortical spreading depression (CSD), which underlies the migraine aura. While our initial efforts focused on potential neuronal mechanisms underlying this network excitability, we have been able to rule those out, and now focus on increasing evidence that the CK1d mutation exerts its effects through astrocytes - specifically through impaired uptake of glutamate and potassium. Our first aim will directly examine glutamate and K+ reuptake on CK1d animals and wild type littermates, using a combination of in vivo two photon microscopy and whole cell electrophysiological recordings. Our hypothesis is that due to its effects on astrocyte syncitial function, the CK1d mutation slows glutamate and K+ reuptake. We will confirm this with CK1d inhibition and overexpression, and direct inhibition of the connexin43 protein (Cx43), a CK1d target. The second aim will take a similar approach while examining CSD, and the third aim will examine sensory network function. Our hypothesis is that impaired astrocytic uptake is the common mechanism that links both phenotypes. If successful we will be able to assess whether the CK1d mutation is necessary and sufficient for the migraine phenotype, and by what specific mechanism(s) it exerts its effects. This work could be important because it would add significantly to evidence that astrocytic reuptake, like neuronal excitability, is a viable path to migraine induction. A second important aspect is that, although the CK1d mutation is undoubtedly rare, it contrasts with all other monogenic migraine models in that mutation carriers have normal migraine attacks (as opposed to attacks associated with hemiplegia), and thus could be more relevant to the majority of migraine sufferers.

偏头痛影响着世界 12% 的人口，是全球残疾的主要原因之一。然而 令人惊讶的是，人们对这种疾病的基本特征知之甚少。我们帮助开发了一种新的小鼠基因 偏头痛模型，我们现在建议检查其机制。酪蛋白激酶 1 delta (CK1d) 小鼠 表达了来自患有先兆偏头痛的家族的突变。我们发现CK1d小鼠有两个关键 与偏头痛相关的表型：对偏头痛触发的感觉网络反应增加，以及 增加对皮质扩散性抑制（CSD）的易感性，这是偏头痛先兆的基础。虽然我们的 最初的努力集中在该网络兴奋性背后的潜在神经元机制，我们已经能够 排除这些可能性，现在重点关注越来越多的证据表明 CK1d 突变通过 星形胶质细胞 - 特别是通过谷氨酸和钾的摄取受损。我们的第一个目标是直接检查 使用体内两种方法的组合，对 CK1d 动物和野生型同窝动物进行谷氨酸和 K+ 再摄取 光子显微镜和全细胞电生理记录。我们的假设是，由于它的影响 星形胶质细胞合胞功能，CK1d 突变会减慢谷氨酸和 K+ 的再摄取。我们将通过以下方式确认这一点 CK1d 抑制和过度表达，以及直接抑制 CK1d 靶点连接蛋白 43 蛋白 (Cx43)。这 第二个目标将在检查 CSD 时采取类似的方法，第三个目标将检查感觉网络 功能。我们的假设是星形胶质细胞的摄取受损是连接两者的共同机制 表型。如果成功，我们将能够评估 CK1d 突变是否是必要且充分的 偏头痛表型，以及它通过什么具体机制发挥作用。这项工作可能很重要 因为它将显着增加星形胶质细胞再摄取（如神经元兴奋性）是一种可行的证据 诱发偏头痛的途径。第二个重要的方面是，尽管CK1d突变无疑是罕见的， 它与所有其他单基因偏头痛模型形成鲜明对比，因为突变携带者有正常的偏头痛发作 （相对于与偏瘫相关的发作），因此可能与大多数患者更相关 偏头痛患者。