The Rat Pre-Formed Alpha-Synuclein Fibril Model of Parkinson's Disease

帕金森病大鼠预制α-突触核蛋白原纤维模型

基本信息

批准号：
9387180
负责人：
Caryl E Sortwell
金额：
$ 39.77万
依托单位：
MICHIGAN STATE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2017
资助国家：
美国
起止时间：
2017-08-15 至 2018-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9387180
关键词：
Amygdaloid structure Animal Model Area Behavior Bilateral Biological Models Blood Body Size Clinical Corpus striatum structure Data Denervation Development Diagnosis Disease Disease model Dopamine Drug Kinetics Endopeptidase K Exhibits Female Genetic Human Image Impairment Injectable Injection of therapeutic agent Intervention Ipsilateral Levodopa Lewy Bodies Light Measurable Memory impairment Modeling Monitor Motor Mus Nerve Degeneration Parkinson Disease Pathologic Pathology Patients Performance Peripheral Phase Positron-Emission Tomography Proteins Rattus Reporting Resistance Seeds Substantia nigra structure Synapses Testing Thioflavin S Time Tyrosine 3-Monooxygenase Ubiquitin Validation alpha synuclein brain size clinical predictors clinical translation dopamine transporter dopaminergic neuron gender difference in vivo in vivo imaging male motor deficit motor impairment motor symptom nerve supply non-drug novel pars compacta pharmacodynamic biomarker pre-clinical sample collection synucleinopathy treatment strategy validation studies vesicular monoamine transporter

项目摘要

Until recently, no animal model of Parkinson's disease (PD) has adequately incorporated both widespread alpha-synuclein (α-syn) pathology and protracted significant nigrostriatal degeneration. In 2012, Luk and colleagues described how intrastriatal injection of synthetic α-syn preformed fibrils (PFFs) into wildtype (WT) mice seeded endogenous accumulation of Lewy Body (LB)-like intracellular α-syn inclusions and ultimate nigrostriatal degeneration. In light of the fact that the rat model system offers distinct advantages over mice (fine motor behaviors, greater synaptic complexity, genetics and pharmacokinetics more similar to humans, larger brain and body size more amenable to neurosurgical interventions and sample collection), we recently characterized the results of unilateral injection of mouse α-syn PFFs into the striatum of rats. Similar to the mouse, we observed phosphorylated α-syn intraneuronal accumulations in several areas that innervate the striatum, most prominently the frontal and insular cortices, the amygdala, and the substantia nigra pars compacta (SNpc). α-Syn accumulations co-localized with ubiquitin, p62, and were thioflavin-S-positive and proteinase-k resistant. Although α-syn inclusions within the SNpc remained ipsilateral to striatal injection, we observed bilateral reductions in nigral dopamine neurons 6 months following α-syn PFF injection. Further, PFF injected rats exhibited reductions in striatal dopaminergic innervation as well as deficits in striatal dopamine and metabolites. This initial study demonstrates that α-syn PFFs are sufficient to seed the pathological conversion and propagation of endogenous α-syn to induce a progressive, neurodegenerative model of α-synucleinopathy in rats. In the present IGNITE application we seek to identify which α-syn species (human, mouse, rat) results in consistent loss of 60% nigral dopamine neurons over the course of 4 months after intrastriatal injection into rats (Aim 1). Once identified, we will conduct internal validation studies to systematically characterize the time course and magnitude of α-syn pathology, striatal dopamine and metabolite loss, levels of striatal dopaminergic innervation (tyrosine hydroxylase, vesicular monoamine transporter, and dopamine transporter) and deficits in motor behaviors (Aim 2). Lastly, we will conduct PD-relevant external validation studies including: 1) investigating whether PFF-induced motor deficits are reversible with levodopa and 2) conduct non-invasive longitudinal in vivo imaging of nigrostriatal DA synthesis, storage and turnover using positron emission tomography (PET) (Aim 3). We propose that optimization, internal validation and external validation studies in the progressive rat α-syn PFF PD model will allow for direct comparison to clinical metrics in PD patients and facilitate the development of novel disease modifying therapies.

直到最近，帕金森病 (PD) 的动物模型还没有充分纳入广泛的 α-突触核蛋白 (α-syn) 病理学和长期显着的黑质纹状体变性。2012 年，Luk 及其同事描述了纹状体注射合成 α-syn 是如何形成原纤维的。 PFFs）到野生型（WT）小鼠中接种路易体（LB）样细胞内α-syn内源性积累的内含物和最终鉴于大鼠模型系统比小鼠具有明显的优势（精细运动行为、突触复杂性更高、遗传学和药代动力学更类似于人类、更大的大脑和身体尺寸更适合神经外科干预和样本收集），我们最近表征了将小鼠 α-syn PFF 单侧注射到大鼠纹状体中的结果，与小鼠类似，我们在几个神经元内观察到磷酸化 α-syn 积聚。支配纹状体的区域，最显着的是额叶和岛叶皮质、杏仁核和黑质致密部 (SNpc)，α-Syn 积累与泛素、p62 共定位，并且是硫黄素-S 阳性和蛋白酶-k。尽管 SNpc 内的 α-syn 内含物仍保留在纹状体注射的同侧，但我们观察到双侧减少。注射 α-syn PFF 后 6 个月，黑质多巴胺神经元表现出纹状体多巴胺能神经支配的减少以及纹状体多巴胺和代谢物的缺陷。内源性 α-syn 的传播诱导大鼠进行性 α-突触核蛋白病神经退行性模型在目前的 IGNITE 应用中，我们寻求。确定哪些 α-syn 物种（人、小鼠、大鼠）会导致大鼠纹状体注射后 4 个月内持续损失 60% 的黑质多巴胺神经元（目标 1）。通常表征 α-syn 病理学的时间过程和程度、纹状体多巴胺和代谢物损失、纹状体多巴胺能神经支配水平（酪氨酸羟化酶、囊泡单胺）最后，我们将进行与 PD 相关的外部验证研究，包括：1) 调查 PFF 引起的运动缺陷是否可以用左旋多巴逆转；2) 进行非侵入性纵向研究。使用正电子发射断层扫描 (PET) 对黑质纹状体 DA 合成、储存和周转进行体内成像（目标 3）。 α-syn PFF PD 模型将允许与 PD 患者的临床指标进行直接比较，并促进新型疾病修饰疗法的开发。