Regulation of autophagy in dopaminergic cell death

多巴胺能细胞死亡中自噬的调节

• 批准号: 7470602
• 负责人: Charleen T Chu
• 金额: $ 29.83万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-08-01 至 2012-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7470602
• 关键词: 1-Methyl-4-phenylpyridinium; 3-methyladenine; Abbreviations; Acute; Adam11 gene; Address; Antioxidants; Autophagocytosis; Biochemical; Brain Diseases; CCL22 gene; Cardiolipins; Cell Death; Cell Line; Cells; Chronic; Complex; Condition; Development; Dominant-Negative Mutation; Dopamine; Dopaminergic Cell; Dose; Equilibrium; Extracellular Signal Regulated Kinases; Future; Genes; Green Fluorescent Proteins; Impairment; In Vitro; Injury; Lead; Lecithin; Lewy Body Disease; Life; Light; Localized; MAP Kinase Gene; MAP1 Microtubule-Associated Protein; Mediating; Membrane; Metabolic; Metabolic Diseases; Midbrain structure; Mitochondria; Mitogen-Activated Protein Kinases; Modeling; Molecular; Morphology; Mus; N-terminal; Nerve Degeneration; Neurites; Neurodegenerative Disorders; Neuronal Injury; Neurons; Neurotoxins; Nutrient; Organelles; Oxidants; Oxidation-Reduction; Oxidative Stress; Oxidopamine; Parkinson Disease; Pathologic; Phosphatidylethanolamine; Phosphatidylinositols; Phosphatidylserines; Phospholipid Signaling Pathway; Phospholipids; Phosphotransferases; Physiological; Play; Process; Protein Isoforms; Protein Kinase; Proteins; RNA Interference; Reactive Oxygen Species; Reagent; Regulation; Research; Research Personnel; Role; Signal Transduction; Small Interfering RNA; Starvation; Stress; Substantia nigra structure; Superoxide Dismutase; System; Testing; Toxic effect; Toxin; Transgenic Organisms; Tyrosine 3-Monooxygenase; Vacuole; age related; cellular imaging; chlorambucil/dactinomycin/methotrexate protocol; deprivation; design; dopaminergic neuron; extracellular; in vivo; in vivo Model; inhibitor/antagonist; injured; inorganic phosphate; insight; kinase inhibitor; mitochondrial autophagy; monodansylcadaverine; neurotoxic; novel; oxidation; phosphatidylethanolamine; programs; response; wortmannin

DESCRIPTION (provided by applicant): Dopaminergic (DA) neurons are sensitive to oxidative insults and degenerate in age-related neurodegenerative diseases. A morphologic form of regulated cell death characterized by prominent autophagic vacuoles (AVs) has been identified in neurons. Autophagy is normally a highly regulated process sequestering cytoplasmic components for lysosomal degradation. However, dysregulated or excessive autophagy can be harmful to cells, producing a condition that can be conceptualized as "autophagic stress." Although AVs are observed in degenerating DA neurons in Parkinson disease and its in vitro and in vivo models, the role of autophagy in DA neuronal injury remains to be elucidated. Our studies indicate that oxidative neurotoxins elicit increased mitochondrial autophagy in DA neurons. Moreover, the regulation of this injury-induced autophagy is different from that of nutrient-deprivation systems. This proposal investigates the hypotheses that: autophagy contributes to neurite retraction and cell death in injured DA neurons, and that reactive oxygen species and MARK signals regulate injury-induced autophagy. We will use the complex I inhibitor MPP+ to produce mitochondria-targeted injury, and the redox cycling 6- hydroxydopamine to model generalized oxidative stress, comparing acute and chronic treatments. A combination of molecular, biochemical, live cell imaging and transgenic approaches will be applied to DA cell lines, primary midbrain cultures and mice to determine the role of autophagy in DA neurite retraction and cell death, and to study MAPK and oxidative phospholipid signals involved in its regulation. Completion of these studies will yield important insights into mechanisms by which autophagic responses regulate DA neurite degeneration and cell death during oxidative neuronal injuries. Relevance: Mitchondrial impairment and autophagic stress are prominent features of Parkinson/Lewy body disease. In contrast to physiologic conditions, inducing autophagy in the presence of dysregulating pathologic forces may promote cell death. A better understanding of mechanisms that contribute to autophagic stress will help focus future research efforts to restore balance to the system. Thus, studying the role and regulation of autophagic responses in oxidatively-injured neurons may enhance development of novel therapies applicable to age-related neurodegenerative diseases and other brain disorders involving oxidative stress.

描述（由申请人提供）：多巴胺能（DA）神经元对氧化损伤敏感，并且与年龄相关的神经退行性疾病变性。在神经元中已经鉴定出以显着自噬液泡（AV）为特征的调节细胞死亡的形态形式。自噬通常是高度调节的过程，用于隔离溶酶体降解的细胞质成分。但是，失调或过度自噬可能对细胞有害，产生可以被概念化为“自噬应力”的疾病。尽管在帕金森氏病及其体外和体内模型的DA神经元中观察到AV，但自噬在DA神经元损伤中的作用仍有待阐明。我们的研究表明，氧化神经毒素会引起DA神经元中线粒体自噬的增加。此外，这种损伤引起的自噬的调节与营养剥夺系统的调节不同。该提案调查了以下假设：自噬有助于受伤的DA神经元的神经突收缩和细胞死亡，而活性氧和标记信号调节了损伤引起的自噬。我们将使用复合物I抑制剂MPP+产生靶向线粒体的损​​伤，以及氧化还原循环6-羟基多巴胺以比较急性和慢性治疗。分子，生化，活细胞成像和转基因方法的结合将应用于DA细胞系，原代中脑培养物和小鼠，以确定自噬在DA神经突收缩和细胞死亡中的作用，并研究MAPK和MAPK和氧化磷脂信号所涉及的磷脂信号。这些研究的完成将产生对自噬反应在氧化神经元损伤过程中调节DA神经突变性和细胞死亡的机制的重要见解。相关性：米氏障碍和自噬应激是帕金森氏症/路易人身体疾病的突出特征。与生理条件相反，在存在失调的病理力量的情况下诱导自噬可能促进细胞死亡。对有助于自噬压力的机制有更好的理解将有助于将未来的研究工作集中在恢复系统之间。因此，研究自噬反应在氧化造成的神经元中的作用和调节可能会增强适用于与年龄相关的神经退行性疾病和其他涉及氧化应激的脑疾病的新型疗法的发展。