Investigating the RhoA/ROCK pathway for the treatment of Alzheimer's disease

研究治疗阿尔茨海默病的 RhoA/ROCK 通路

• 批准号: 8425721
• 负责人: Jeremy H. Herskowitz
• 金额: $ 8.88万
• 依托单位: EMORY UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-09-30 至 2014-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8425721
• 关键词: Address; Affect; Alzheimer disease prevention; Alzheimer' s Disease; American; Amino Acid Substitution; Amyloid; Amyloid deposition; Autopsy; Award; Basic Science; Binding; Biological; Biological Models; Brain; Cells; Cellular biology; Clinical; Cognition; Coupled; Data; Dementia; Dendritic Spines; Dependovirus; Development; Disease; Disease Progression; Drug Delivery Systems; Education; Ethics; Event; Experimental Models; Faculty; Family member; Fostering; Functional disorder; Future; Generations; Goals; Hippocampus (Brain); Human; Impaired cognition; Injection of therapeutic agent; International; Intervention; Knowledge; Laboratories; Lead; Leadership; Learning; Marines; Measures; Mediating; Mentors; Methodology; Microscopy; Modeling; Molecular; Morphology; Mus; Nerve Degeneration; Neurites; Neurodegenerative Disorders; Neurology; Neurons; Neurosciences; Onset of illness; Pathogenesis; Pathology; Pathway interactions; Phase; Phosphotransferases; Postdoctoral Fellow; Production; Protein Isoforms; Protein Kinase; Proteins; ROCK1 gene; Research; Resistance; Rodent; Scientist; Signal Transduction; Societies; Staging; Students; Symptoms; Synaptic plasticity; Techniques; Testing; Therapeutic; Time; Training; Translating; Universities; Wood material; Work; aging brain; base; behavior test; brain tissue; career; cognitive function; cognitive reserve; cost; design; end stage disease; extracellular; improved; in vivo; innovation; insight; light microscopy; meetings; member; mouse model; mutant; nervous system disorder; neuropathology; prevent; programs; rho; rho GTP-Binding Proteins; skills; small hairpin RNA; symposium

DESCRIPTION (provided by applicant): My career goal is to be a successful, independent academic research scientist with a laboratory that contributes important insights into Alzheimer's disease (AD) as well as other neurodegenerative diseases and fosters the training of students and fellows. My long-term research goals are to translate basic science discoveries about the mechanisms of neurodegeneration and AD pathogenesis into rational therapies. The K99/R00 Pathway to Independence award will facilitate important career training that will provide a path to establish my own independent research group and initiate new avenues of AD research. Training: Dr. James Lah will be my primary mentor and Dr. Allan Levey will be my co-mentor for the K99 phase of this application, and working together we have developed a plan to provide the necessary career training that will allow for the execution of the proposed research and my transition to independence. In addition to my mentors, a committee of faculty members, including Drs. Gary Bassell, David Weinshenker, Marla Gearing, Ranjita Betarbet, and Richard Kahn, will provide intellectual guidance and technical support during the K99 phase. Dr. Bassell will share his expertise with state-of-the-art microscopy techniques, while Dr. Weinshenker will provide training for rodent behavioral testing. Drs. Gearing and Betarbet will assist with immunohistochemical studies of postmortem human brain tissues and stereotaxic injection of mice, respectively, and Dr. Kahn will offer wisdom and career guidance to facilitate my transition to independence. In the first year of the K99 phase, I will attend a Cold Springs Harbor Laboratory training course in Molecular Neurology and Neuropathology and the Analytical & Quantitative Light Microscopy course at the Marine Biological Laboratory in Woods Hole. In year two, I will attend the University of Pittsburgh Course in Scientific Management and Leadership which is an interactive learning forum designed to equip senior postdoctoral fellows with the knowledge and professional competencies to lead innovative and productive research programs. As a postdoctoral fellow, I have presented my research every year at the annual Society for Neuroscience meeting, and I will continue this tradition through the K99 and R00 phases. I also will present my findings at the International Conference on Alzheimer's disease in 2013. I will attend weekly seminars in the Dept. of Neurology and Cell Biology and participate in a training course on scientific ethics sponsored by the Emory University Office of Postdoctoral Education. Research: Cognitive decline is a clinical hallmark of progression from healthy brain aging to Alzheimer's disease (AD), while increased production and accumulation of amyloid-¿ (A¿) is a pathological hallmark of AD. There is strong evidence that the observed cognitive impairment in AD is in part due to A¿'s negative impact on synaptic plasticity. Therefore, designing therapeutics that simultaneously boost cognitive reserve and function as well as decrease A¿ production may prevent AD onset and treat end-stage disease. RhoA, a Rho GTPase family member, is a well-studied regulator of neuronal outgrowth and synaptic plasticity. The principle downstream effectors of RhoA are the Rho-associated coiled-coil containing protein kinases (ROCK), ROCK1 and ROCK2. Active RhoA promotes antagonistic effects on synaptic plasticity, and extracellular A¿ induces RhoA activity. Furthermore, there is an accordant relationship between RhoA activity and A¿ generation. Development of AD pathology likely begins many years prior to clinical symptom onset, and during this time, we propose that A¿ accumulation activates the RhoA/ROCK pathway which thereby negatively impacts synaptic plasticity and fuels production of A¿. The RhoA/ROCK pathway is an exciting target for pharmacologic intervention, but progress is hampered by the ambiguity of which downstream RhoA signaling events are attributable to ROCK1 or ROCK2 in brain. Importantly, the proposed studies will be the first to evaluate targeted disruption of ROCK1 or ROCK2 in the same experimental model system in vivo. We hypothesize that RhoA/ROCK activity increases as AD progresses and that inhibition of the RhoA-ROCK2 pathway will improve cognitive function in AD. To test this postulate, we will determine if RhoA/ROCK activity is amplified in asymptomatic AD (early stages of disease) and symptomatic AD (end-stage disease) cases by measuring RhoA, ROCK1, and ROCK2 activity in control, asymptomatic AD, and symptomatic AD brains. Next, we will determine how targeted knockdown of ROCK1 or ROCK2 affects cognition dysfunction and A¿ deposition in an AD mouse model by delivering adeno-associated virus expressing ROCK isoform specific shRNA to the hippocampus. Finally, we will test the model that activation or inhibition of RhoA reflects ROCK2-mediated effects in brain by measuring changes in dendritic spine morphology as well as A¿ production following pharmacological modulation of RhoA activity coupled with targeted shRNA reduction of ROCK1 or ROCK2. Results from these studies will facilitate future development of drugs targeted against the RhoA/ROCK pathway for the treatment and prevention of AD. In addition, the intellectual and technical skills I acquire over the K99 training period will allow me to establish an independent research program to investigate the functional importance of specific ROCK isoforms in AD as well as other models of neurological disorders. PUBLIC HEALTH RELEVANCE: There are no known therapies for the underlying disease-causing mechanisms of Alzheimer's disease, the leading cause of dementia. The RhoA/ROCK pathway influences critical aspects of Alzheimer's disease pathogenesis, including cognitive decline and amyloid accumulation. Studying the RhoA/ROCK pathway will facilitate the development of drugs targeted against this pathway for the treatment and prevention of Alzheimer's disease.

描述（由申请人提供）：我的职业目标是成为一名成功的，独立的学术研究科学家，拥有一个实验室，为阿尔茨海默病（AD）以及其他神经退行性疾病提供重要见解，并促进学生和研究员的培训。我的长期研究目标是将有关神经变性和AD发病机制的基础科学发现转化为合理的治疗方法。K99/R00独立之路奖将促进重要的职业培训，这将为我建立自己的独立研究小组和开创AD研究的新途径提供途径。培训：James Lah博士将是我的主要导师，Allan Levey博士将是我在K99阶段的联合导师，我们一起制定了一个计划，提供必要的职业培训，使我能够执行拟议的研究并过渡到独立。除了我的导师之外，一个由教员组成的委员会，包括dr。Gary Bassell、David Weinshenker、Marla Gearing、Ranjita Betarbet和Richard Kahn将在K99阶段提供智力指导和技术支持。Bassell博士将分享他在最先进的显微镜技术方面的专业知识，而Weinshenker博士将提供啮齿动物行为测试方面的培训。Drs。Gearing和Betarbet将分别协助进行死后人类脑组织的免疫组织化学研究和小鼠立体定向注射，Kahn博士将提供智慧和职业指导，以促进我向独立过渡。在K99阶段的第一年，我将参加冷泉港实验室的分子神经病学和神经病理学培训课程，以及伍兹霍尔海洋生物实验室的分析与定量光显微镜课程。在第二年，我将参加匹兹堡大学的科学管理和领导力课程，这是一个互动式学习论坛，旨在为高级博士后提供知识和专业能力，以领导创新和富有成效的研究项目。作为一名博士后，我每年都在神经科学学会的年度会议上展示我的研究，我将在K99和R00阶段继续这一传统。我还将在2013年的阿尔茨海默病国际会议上展示我的发现。我将参加神经病学和细胞生物学系每周一次的研讨会，参加由埃默里大学博士后教育办公室主办的科学伦理培训课程。研究：认知能力下降是从健康大脑老化到阿尔茨海默病（AD）进展的临床标志，而淀粉样蛋白-¿（a¿）的产生和积累增加是AD的病理标志。有强有力的证据表明，在AD中观察到的认知障碍部分是由于A¿对突触可塑性的负面影响。因此，设计同时增强认知储备和功能以及减少A¿产生的治疗方法可能会预防AD的发作并治疗终末期疾病。RhoA是Rho GTPase家族的成员，是一个被广泛研究的神经元生长和突触可塑性的调节剂。RhoA的主要下游效应物是RhoA相关的含蛋白激酶（ROCK）、ROCK1和ROCK2。活跃的RhoA促进突触可塑性的拮抗作用，细胞外A¿诱导RhoA活性。此外，RhoA活性与A¿生成之间存在一致的关系。阿尔茨海默病的病理发展可能在临床症状出现前很多年就开始了，在这段时间里，我们认为A¿积累激活了RhoA/ROCK通路，从而对突触可塑性产生负面影响，并促进A¿的产生。RhoA/ROCK通路是一个令人兴奋的药物干预靶点，但由于下游RhoA信号事件在大脑中是由ROCK1还是ROCK2引起的模糊，进展受到阻碍。重要的是，拟议的研究将首次在体内同一实验模型系统中评估ROCK1或ROCK2的靶向破坏。我们假设RhoA/ROCK活性随着AD的进展而增加，抑制RhoA- rock2途径将改善AD的认知功能。为了验证这一假设，我们将通过测量对照组、无症状AD和症状AD大脑中的RhoA、ROCK1和ROCK2活性，来确定RhoA/ROCK活性是否在无症状AD（疾病早期）和有症状AD（终末期疾病）病例中被放大。接下来，我们将通过将表达ROCK异构体特异性shRNA的腺相关病毒传递到海马，确定ROCK1或ROCK2的靶向敲除如何影响AD小鼠模型中的认知功能障碍和A¿沉积。最后，我们将通过测量树突棘形态的变化以及RhoA活性的药理学调节加上靶向shRNA减少ROCK1或ROCK2后A¿的产生，来测试RhoA的激活或抑制反映ROCK2在大脑中的介导作用的模型。这些研究的结果将有助于未来开发针对RhoA/ROCK通路的药物来治疗和预防AD。此外，我在K99培训期间获得的智力和技术技能将使我能够建立