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

• 批准号: 9751424
• 负责人: Caryl E Sortwell
• 金额: $ 36.24万
• 依托单位: MICHIGAN STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-08-01 至 2022-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9751424
• 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; Impairment; Injections; 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

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，帕金森氏病（PD）的动物模型还充分纳入了宽度 α-突触核蛋白（α-Syn）病理学和持久的明显的黑质性变性。在2012年卢克和 同事描述了纹状体内注射合成α-Syn的原纤维（PFF）如何进入野生型（WT） 小鼠在Lewy体（LB）类似细胞内α-Syn夹杂物和最终的内源性内源性积累 黑质性变性。鉴于大鼠模型系统比小鼠具有不同的优势 （精细运动行为，更大的突触复杂性，遗传学和药代动力学与人类更相似， 更大的大脑和体型更适合神经外科干预和样本收集），我们最近 表征了小鼠α-Syn PFF在大鼠纹状体中的单侧注射的结果。类似于 小鼠，我们观察到磷酸化的α-syn神经内神经元积累，在几个区域中 纹状体，最突出的额叶和岛状皮质，杏仁核和黑质Nigra pars comcacta（SNPC）。 α-Syn积累与泛素，p62共定位，是硫代黄酮-S阳性的， 蛋白酶-K耐药。尽管SNPC内的α-Syn夹杂物仍然是纹状体注射的同侧，但我们 在注射α-Syn PFF后6个月，观察到的双侧多巴胺神经元的双侧减少。此外，PFF 注入的大鼠暴露了纹状体多巴胺能神经的减少以及纹状体多巴胺的缺陷 和代谢物。这项最初的研究表明，α-syn PFF足以播种病理学 内源性α-Syn的转化和传播诱导α-进行的进行性神经退行性模型 大鼠的肌肌病。在当前的点火应用中，我们试图确定哪些α-syn物种（人类， 小鼠，大鼠）在4个月后的4个月内，导致持续损失60％的ni骨多巴胺神经元 纹状体内注射到大鼠中（AIM 1）。一旦确定，我们将进行内部验证研究 系统地表征了α-Syn病理学，纹状体多巴胺和 代谢物损失，纹状体多巴胺能神经的水平（酪氨酸羟化酶，囊泡单胺 转运蛋白和多巴胺转运蛋白）并在运动行为中定义（AIM 2）。最后，我们将进行PD与PD相关 外部验证研究，包括：1）研究PFF诱导的电机是否定义 左旋多巴可逆，2）在骨纹状体DA合成中进行非侵入性纵向成像， 使用极性发射断层扫描（PET）的存储和周转（AIM 3）。我们提出了优化， 进行性大鼠α-Syn PFF PD模型中的内部验证和外部验证研究将允许 与PD患者的临床指标直接比较，并促进了新型疾病的发展 疗法。