Studies of Hirano Bodies in Living Cells

描述（由申请人提供）：Hirano小体是细胞质内含物，与衰老的细胞病理学和多种神经退行性疾病（包括阿尔茨海默病、帕金森病和肌萎缩性侧索硬化症）相关。由于以前对平野小体的研究是在保存的临床脑样本上进行的，因此没有关于平野小体对细胞生理学、衰老或神经退行性疾病的影响的直接信息。最近已经描述了在培养细胞中形成平野小体的模型。模型平野小体是从平野小体在病理学样本中的所有标准所描述的先前的超微结构和免疫组化研究平野小体难以区分。由于平野小体是与许多重大疾病相关的广泛类型的细胞质蛋白包涵体，因此确定其对神经元细胞生理学的影响是重要的。本项目的目的是测试以下3个备选假设：1）Hirano小体促进/反映细胞病理学和毒性; 2）Hirano小体是适应性结构，在已知导致神经退行性疾病的应激下促进神经元细胞的存活;或3）Hirano小体对生理应激下神经元细胞的存活没有影响。将确定Hirano小体对涉及神经变性疾病病理学的5种应激的神经毒性的影响。这5个重点是：1）氧化应激，破坏蛋白质、脂质和核酸; 2）谷氨酸兴奋性毒性，引发细胞内钙的长期升高; 3）缺血（ATP耗竭）最常与中风或缺氧相关; 4）Ab肽，引发阿尔茨海默病病理学的主要候选者;和5）淀粉样前体蛋白（AICD）的胞内胞质结构域，其可以启动程序性细胞死亡。这些结果将提供一个直接的测试的假设，平野小体影响神经细胞的生存挑战与生理应激，促进死亡或存活的神经元疾病。阐明平野小体在疾病中的潜在作用是可能开发动物模型、干预或治疗的先决条件。

DESCRIPTION (provided by applicant): Hirano bodies are cytoplasmic inclusions described in association with the cellular pathology of aging, and a variety of neurodegenerative diseases including Alzheimer's disease, Parkinson's disease, and Amyotrophic Lateral Sclerosis. Since previous studies of Hirano bodies have been performed on preserved clinical brain samples, there is no direct information on the effects of Hirano bodies on cell physiology, aging, or neurodegenerative disease. A model for formation of Hirano bodies in cultured cells has recently been described. The model Hirano bodies are indistinguishable from Hirano bodies in pathology samples in all criteria described by prior ultrastructural and immunohistochemical studies of Hirano bodies. Since Hirano bodies are a widespread type of cytoplasmic protein inclusion associated with numerous significant diseases, it is important to determine their effects on the physiology of neuronal cells. The aim of this project is to test the following 3 alternative hypotheses: 1) Hirano bodies promote/ reflect cellular pathology and toxicity; 2) Hirano bodies are adaptive structures that promote survival of neuronal cells under stresses that are known to contribute to neurodegenerative diseases; or 3) Hirano bodies have no effect on survival of neuronal cells under physiological stress. The effect of Hirano bodies on the neurotoxicity of 5 stresses implicated in the pathology of neurodegenerative disease will be determined. These 5 stresses are: 1) oxidative stress that damages protein, lipid, and nucleic acid; 2) glutamate excitotoxicity that initiates prolonged elevation of intracellular calcium; 3) ischemia (ATP depletion) most commonly associated with stroke or hypoxia; 4) Ab peptide, the leading candidate for initiation of the pathology of Alzheimer's disease; and 5) the intracellular cytoplasmic domain of the amyloid precursor protein (AICD) that can initiate programmed cell death. The results will provide a direct test of the hypothesis that Hirano bodies affect the survival of neuronal cells challenged with physiological stress by promoting either the death or the survival of neurons in disease. Elucidation of the potential roles of Hirano bodies in disease is prerequisite to possible development of animal models, interventions, or therapies.