Essential Tremor: Gene expression profiling in cerebellar Purkinje cells

特发性震颤：小脑浦肯野细胞的基因表达谱

• 批准号: 8320096
• 负责人: PHYLLIS L FAUST
• 金额: $ 20万
• 依托单位: COLUMBIA UNIVERSITY HEALTH SCIENCES
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-01 至 2014-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8320096
• 关键词: Address; Adult; Affect; Age; Alzheimer' s Disease; Animal Model; Autopsy; Axon; Bioinformatics; Biology of Aging; Brain; Brain region; Cell model; Cell physiology; Cells; Cellular biology; Cerebellar cortex structure; Cerebellum; Collection; Complex; Data; Degenerative Disorder; Disease; Elderly; Essential Tremor; Evaluation; Event; Familial Tremors; Family; Freezing; Functional disorder; Funding Mechanisms; Future; Gene Expression; Gene Expression Profiling; Genes; Genetic; Genomics; Gliosis; Goals; Hereditary Disease; High Prevalence; Human; Hypertrophy; Individual; Investigation; Kinetics; Label; Lead; Methods; Metric; Modeling; Molecular; Movement; Myoepithelial cell; Nerve Degeneration; Neuroglia; Neurologic; Neurons; Output; Parkinson Disease; Pathogenesis; Pathologic; Pathology; Pathway interactions; Patients; Pattern; Prevalence; Process; Proteins; Purkinje Cells; RNA; Recurrence; Regulation; Research; Resources; Sampling; Screening procedure; Sum; Susceptibility Gene; Swelling; Time; Tissues; Torpedo; Transgenic Mice; Tremor; United States National Institutes of Health; arm; axon regeneration; base; cRNA Probes; improved; interest; laser capture microdissection; mind control; nervous system disorder; neuronal cell body; neuronal survival; prospective; receptor; repository

DESCRIPTION (provided by applicant): Essential tremor (ET) is among the most common neurological diseases, occurring in 4% of adults age 40 and older, and even more frequently in advanced age (i.e., 7-8% by age 70 and >20% by age 90+). Despite its high prevalence, the underlying pathogenesis of ET is poorly understood, and, as a consequence, current treatments are empiric and have poor efficacy. Human postmortem studies are currently the most robust avenue for advancing the study of the underlying pathophysiological mechanisms of ET, as genes have yet to be identified for ET, and no transgenic mice currently exist to provide an animal model. Our group has been conducting systematic postmortem studies, which have revealed identifiable structural changes in the brains of ET cases. We have demonstrated that neuropathologic findings in the vast majority of ET cases (>90%) localize to the cerebellum itself and, in particular, to the Purkinje cells (PC), which provide the entire neuronal output from cerebellar cortex. In ET brains, there is a 6- to 7-fold increase in damaged PC axons, identified as rounded swellings of the proximal portion of the PC axon (i.e., "torpedoes"). Strongly correlating with this PC axonal damage is an approximate 30-40% reduction in the number of PCs and an increase in the number of heterotopic (displaced) PCs. Our ongoing pathologic studies further indicates that the torpedo is likely only a marker of advanced PC axonal damage. Earlier changes are now becoming evident in ET brains, including a graded increase in small to intermediate-sized thickenings of the proximal PC axon (i.e., presumed precursor- torpedoes) and increases in PC recurrent axon collateral formation with increased sprouting along the intracortical segment of PC axons. These studies implicate PC degeneration as a core feature of the disease process in ET, associated with slowly progressive axonal damage and significant remodeling of intracortical cerebellar connectivity. While these postmortem studies have advanced our understanding of disease pathogenesis to a cellular level, it is time to now proceed to a molecular understanding. In this proposal, we will address whether molecular alterations can be identified in cerebellar PCs from ET patients vs. neurologically normal controls. We will perform gene expression analyses by microarray screening on RNA isolated from PCs of ET versus control autopsy brains. We will employ laser-capture microdissection to specifically target PCs, thereby facilitating a precise evaluation of cell-specific changes associated with ET. ET brains will be limited to those with an absence of other neurodegenerative pathologies at autopsy. Analysis of the resultant expression data will identify genes and/or molecular pathways that are differentially expressed and/or biologically grouped in ET versus control PCs. Changes in gene expression will be validated by quantitative real time PCR. This study will be the first to initiate a molecular expression approach in ET research, and will provide a basis for proposing molecular causal mechanisms for ET that will be the focus of future investigations.

描述（由申请人提供）：基本震颤（ET）是最常见的神经系统疾病之一，发生在40岁及40岁以上的4％的成年人中，甚至在高龄的年龄较高（即70岁到70岁，到90岁以上）。尽管患病率很高，但ET的潜在发病机理还是很少了解，因此，当前的治疗方法是经验性且功效不佳。人类验尸研究目前是推进ET基础生理生理机制的研究的最强大的途径，因为ET尚未确定基因，目前尚无转基因小鼠提供动物模型。我们的小组一直在进行系统性验尸研究，这些研究揭示了ET病例大脑的可识别结构变化。我们已经证明，在绝大多数ET病例（> 90％）中，神经病理学的发现位于小脑本身，尤其是Purkinje细胞（PC），该细胞（PC）提供了小脑皮质的整个神经元输出。在Et Brains中，受损的PC轴突增加了6至7倍，被确定为PC轴突近端部分的圆周肿胀（即“鱼雷”）。与此PC轴突损伤密切相关，PC数量减少了约30-40％，异位（移位）PC的数量增加。我们正在进行的病理研究进一步表明，鱼雷可能只是晚期PC轴突损伤的标志。现在，在ET脑中，早期的变化正在变得显而易见，包括近端PC轴突的小型至中型增厚（即推测的前体鱼雷）的分级增加，以及PC复发轴突侧壁形成的增加，并增加了沿PC轴突内部段的芽孢杆。这些研究暗示PC变性是ET中疾病过程的核心特征，与缓慢进行性轴突损伤和心脏内小脑连通性的重塑有关。尽管这些死后研究使我们对疾病发病机理的理解提高到了细胞水平，但现在是时候进行分子理解了。在此提案中，我们将解决在ET患者与神经系统正常对照的小脑PC中是否可以鉴定分子改变。我们将通过对从ET和对照尸检大脑的PCS分离的RNA进行微阵列筛选进行基因表达分析。我们将采用激光捕获显微减退来专门针对PC，从而促进对与ET相关的细胞特异性变化的精确评估。 Et Brains将仅限于尸检时没有其他神经退行性病理的患者。对所得表达数据的分析将鉴定在ET与对照PC中差异表达和/或生物学分组的基因和/或分子途径。基因表达的变化将通过定量实时PCR验证。这项研究将是第一个在ET研究中启动分子表达方法的研究，并将为ET提出分子因果机制提供基础，这将是未来研究的重点。