Development of Novel Neuroprotective Agents for Parkinson?s Disease

帕金森病新型神经保护剂的开发

• 批准号: 7533637
• 负责人: Vellareddy Anantharam
• 金额: $ 15.34万
• 依托单位: PK BIOSCIENCES CORPORATION
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-08-15 至 2010-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7533637
• 关键词: 1-Methyl-4-phenylpyridinium; Address; Animal Model; Apoptosis; Apoptotic; Attenuated; Behavioral; Biochemical; Biological Assay; Bradykinesia; Brain region; Caspase; Catalytic Domain; Cell Death; Cell Line; Cell model; Cells; Chemicals; Clinical Management; Complex; Corpus striatum structure; Cultured Cells; DNA Fragmentation; Development; Disease Progression; Disease model; Dominant-Negative Mutation; Dopaminergic Cell; Dose; Effectiveness; Family; Fluorescence Resonance Energy Transfer; Future; Generations; Genetic; Goals; Inhibitory Concentration 50; Knowledge; Lead; Legal patent; Link; Mediating; Modeling; Motor; Muscle Rigidity; Nerve Degeneration; Neurodegenerative Disorders; Neurologic; Neurons; Neuroprotective Agents; Numbers; Oxidative Stress; Oxidative Stress Pathway; Oxidopamine; Parkinson Disease; Parkinsonian Disorders; Pathway interactions; Phase; Phosphotransferases; Play; Process; Property; Protein Isoforms; Protein Kinase; Protein Kinase C; Protein Overexpression; Public Health; Quinones; Range; Recombinant Proteins; Relative (related person); Research; Research Design; Resistance; Role; Screening procedure; Series; Signal Pathway; Signal Transduction; Site; Skeleton; Small Business Funding Mechanisms; Small Business Innovation Research Grant; Small Interfering RNA; Structure; Substantia nigra structure; Symptoms; System; Testing; Therapeutic; Therapeutic Index; Toxin; Treatment Protocols; Tremor; Tyrosine 3-Monooxygenase; Validation; analog; attenuation; base; benzoquinone; caspase-3; cell type; cellular targeting; computerized data processing; cytotoxic; cytotoxicity test; design; dopaminergic neuron; improved; inhibitor/antagonist; kinase inhibitor; member; mutant; neurochemistry; neuron apoptosis; neuron loss; novel; novel strategies; novel therapeutics; pre-clinical; prevent; protective effect; quinone methide; rottlerin; small molecule; therapeutic target

DESCRIPTION (provided by applicant): Parkinson's disease (PD) is a debilitating neurodegenerative disorder characterized by progressive and substantial loss of dopaminergic neurons in the substantia nigra compacta (SNc), resulting in severe neurological signs including tremors, bradykinesia, and rigidity. The existing approaches to PD treatment are mainly focused on alleviating the motor symptoms by compensating for neurochemical deficits, but they fail to halt the progression of the neurodegenerative process. The lack of effective neuroprotective drugs for PD is primarily attributed to a limited understanding of the complex mechanisms involved in the degenerative processes of the nigral dopaminergic system. However, recent elucidation of apoptotic pathways and oxidative stress signaling has offered some important clues that boost hope for development of novel neuroprotective strategies for PD. In this regard, we uncovered a key apoptotic cell death pathway during oxidative insult in PD models involving the proteolytic activation of a novel PKC isoform, PKC4, by caspase-3 to promote apoptosis in dopaminergic neurons. Suppression of proteolytic activation of PKC4 using dominant negative mutants, a caspase-cleavage site resistant mutant, or siRNAs completely rescued dopaminergic neurons from Parkinsonian toxins MPP+ and 6-OHDA- induced apoptotic cell death. Interestingly, we also found that PKC4 is highly expressed in nigral dopaminergic neurons as compared to other cells. Collectively, these findings indicate that PKC4 is a key downstream proapoptotic kinase in dopaminergic cells and may be a promising therapeutic target for PD. Importantly, treatment with the PKC4 inhibitor rottlerin offered excellent protection against behavioral deficits, neurochemical depletion, and nigral dopaminergic neuronal damage in the classic MPTP-induced animal model of PD, confirming that PKC4 is a viable target for development of neuroprotective agents for PD. As a next logical step, this SBIR phase-I application proposes to develop a series of new PKC4 small molecule inhibitors and optimize them to identify lead compounds with a high therapeutic index. The specific objectives of the proposal are: i) To design and synthesize a series of novel PKC4 inhibitor analogs, ii) To profile the selectivity and inhibitory potency of PKC4 inhibitors using a high throughput kinase profiling system, iii) To determine the potential neuroprotective effects of the PKC4 inhibitors in cell culture models of PD. The combination of a validated therapeutic target, integrative study design, and excellent expertise will help us accomplish these important goals. We anticipate identifying a set of lead compounds for testing in PD animal models for future Phase-II application. The overall approach is expected to lead to development of a mechanism- based neuroprotective agent for treatment of PD. PUBLIC HEALTH RELEVANCE: Parkinson's disease is a major progressive neurodegenerative disorder characterized by the cardinal motor symptoms of rigidity, bradykinesia, tremors, and postural instability. The existing therapeutic approach for Parkinson's disease only treats the symptoms and fails to prevent the progression of the neurodegenerative process. Recently, we identified that PKC4 is a novel therapeutic target for development of neuroprotective agents because the kinase plays a key role in apoptotic cell death of nigral dopaminergic neurons. The proposed studies will develop a series of small molecule PKC4 inhibitors and evaluate their neuroprotective properties in Parkinson's disease models. Overall, the knowledge gained from this proposal will lead to development of an effective neuroprotective drug for treatment of Parkinson's disease.

描述（由申请人提供）：帕金森病（PD）是一种衰弱性神经退行性疾病，其特征为黑质（SNc）中多巴胺能神经元的进行性和实质性损失，导致严重的神经系统体征，包括震颤、运动迟缓和僵硬。现有的PD治疗方法主要集中在通过补偿神经化学缺陷来缓解运动症状，但它们未能阻止神经退行性过程的进展。PD缺乏有效的神经保护药物主要是由于对黑质多巴胺能系统退行性过程中所涉及的复杂机制的理解有限。然而，最近阐明的凋亡途径和氧化应激信号提供了一些重要的线索，提高了希望的发展新的神经保护策略的PD。在这方面，我们发现了一个关键的凋亡细胞死亡途径在氧化损伤的PD模型涉及蛋白水解激活的一种新的PKC亚型，PKC 4，caspase-3，以促进多巴胺能神经元的凋亡。使用显性失活突变体、半胱天冬酶切割位点抗性突变体或siRNA抑制PKC 4的蛋白水解活化完全拯救多巴胺能神经元免于帕金森毒素MPP+和6-OHDA诱导的凋亡性细胞死亡。有趣的是，我们还发现，与其他细胞相比，PKC 4在黑质多巴胺能神经元中高度表达。总的来说，这些研究结果表明，PKC 4是多巴胺能细胞中的关键下游促凋亡激酶，可能是PD的一个有前途的治疗靶点。重要的是，在经典的MPTP诱导的PD动物模型中，用PKC 4抑制剂rottlerin治疗提供了针对行为缺陷、神经化学物质消耗和黑质多巴胺能神经元损伤的极好保护，证实了PKC 4是开发PD神经保护剂的可行靶点。作为下一个合乎逻辑的步骤，SBIR第一阶段申请提出开发一系列新的PKC 4小分子抑制剂，并对其进行优化，以确定具有高治疗指数的先导化合物。本研究的具体目标是：i）设计和合成一系列新型PKC 4抑制剂类似物，ii）使用高通量激酶谱分析系统来分析PKC 4抑制剂的选择性和抑制效力，iii）确定PKC 4抑制剂在PD细胞培养模型中的潜在神经保护作用。一个有效的治疗目标，综合研究设计和优秀的专业知识的结合将帮助我们实现这些重要的目标。我们预计将确定一组先导化合物，用于在PD动物模型中进行测试，用于未来的II期应用。总体方法预期将导致开发用于治疗PD的基于机制的神经保护剂。公共卫生相关性：帕金森病是一种主要的进行性神经退行性疾病，其特征在于强直、运动迟缓、震颤和姿势不稳定的主要运动症状。帕金森病的现有治疗方法仅治疗症状，无法防止神经退行性过程的进展。最近，我们发现，PKC 4是一个新的治疗靶点，为发展的神经保护剂，因为激酶在黑质多巴胺能神经元的细胞凋亡中起着关键作用。拟议的研究将开发一系列小分子PKC 4抑制剂，并评估其在帕金森病模型中的神经保护特性。总的来说，从这个建议中获得的知识将导致开发一种有效的神经保护药物来治疗帕金森病。