CADDMR: a Cell-based Assay for Drug Discovery for Mental Retardation Disorders

CADDMR：一种基于细胞的精神发育迟滞药物发现检测方法

• 批准号: 7230318
• 负责人: LINDA L RESTIFO
• 金额: $ 16.49万
• 依托单位: UNIVERSITY OF ARIZONA
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-07-01 至 2009-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7230318
• 关键词: Animals; Biological Assay; Biological Markers; Biological Models; Brain; Brain Diseases; Brain region; Calculi; Cells; Chemical Agents; Cognitive; Cytoskeletal Proteins; Data Analyses; Defect; Development; Disease; Drosophila genus; Drosophila melanogaster; Gene Mutation; Genes; Genetic; Goals; Harvest; Human; In Vitro; Insecta; Java; Learning; Memory; Mental Retardation; Microscopy; Morphology; Mushroom Bodies; Mutation; Neurites; Neurons; Pathway interactions; Patients; Pharmaceutical Preparations; Phenotype; Preclinical Drug Evaluation; Primary Cell Cultures; Public Health; Screening procedure; Speed; Staging; Stereotyping; System; Testing; base; drug discovery; fascin; fly; in vivo; member; mutant; novel therapeutics; pre-clinical; research clinical testing; research study; sexual dimorphism; skills; steroid hormone; tool

DESCRIPTION (provided by applicant): Mental retardation (MR), for which few effective treatments are available, is a common manifestation of developmental brain disorders. This proposal is based on the hypothesis that pharmacological correction of neuronal defects of morphology or plasticity will enhance the acquisition of cognitive skills in MR patients. Mutations of many different genes can cause MR, and many MR genes are members of interconnected genetic pathways that are very highly conserved among animal species. Such conservation provides an opportunity to use genetic model systems to explore novel therapeutic strategies prior to clinical testing. We have developed a primary cell culture assay for identification of abnormal morphology or plasticity of brain neurons with MR-gene mutations, as well as for identification of compounds that normalize the defects. The neurons are from fruit fly (Drosophila melanogaster) mushroom bodies, the best-characterized insect brain region involved in learning and memory, harvested during a stage of peak steroid-hormone-dependent developmental plasticity. When wild-type neurons are cultured in vitro they elaborate an arbor with a highly stereotyped morphology. The assay has revealed normal sexual dimorphism, as well as phenotypes due to single-gene mutations. In some cases, the in vitro culture system is highly sensitive, unmasking defects whose in vivo manifestations are too subtle to be detected by conventional microscopy. To enhance the speed of screening, we are developing NeuronMorphometrics, a set of Java plug-ins for ImageJ that perform semi-automated data analysis. About 75% of human MR genes have a counterpart in Drosophila that is similar enough by sequence to plausibly perform similar functions in the brain. We will screen a subset of Drosophila MR genes which we believe are prime candidates for revealing neuronal morphology and plasticity defects in vitro. In parallel studies, we will focus on the "filagree" phenotype, an abnormal mode of neurite outgrowth in vitro due to genetic loss of a cytoskeletal protein, and screen for compounds that normalize this phenotype. Together, the screens for phenotypes and for corrective chemical agents should set the stage for use of this assay as a stepping stone for drug discovery and development for MR disorders. Public health relevance: Our long-term goal is to treat mental retardation disorders with drugs that fix the underlying abnormalities of brain development. The proposed experiments are an important step toward that goal.

描述（由申请人提供）：智力低下（MR），几乎没有有效的治疗方法是发育性脑部疾病的常见表现。该提议基于以下假设：形态或可塑性神经元缺陷的药理校正将增强MR患者认知技能的获取。许多不同基因的突变会引起MR，许多MR基因是相互联系的遗传途径的成员，在动物物种中非常保守。这种保护提供了使用遗传模型系统在临床测试之前探索新型治疗策略的机会。我们已经开发了一种原发性细胞培养测定法，用于鉴定具有MR-GENE突变的脑神经元异常形态或可塑性，以及鉴定出归一化缺陷的化合物。神经元来自果蝇（果蝇Melanogaster）蘑菇体，这是与学习和记忆相关的最典型的昆虫大脑区域，在类固醇激素依赖性的发育塑料量的阶段收获。当在体外培养野生型神经元时，它们会阐述具有高度定型形态的乔木。该测定法显示了正常的性二态性，以及由于单基因突变而引起的表型。在某些情况下，体外培养系统是高度敏感的，揭示了缺陷，其体内表现太微妙，无法通过常规显微镜检测到。为了提高筛选的速度，我们正在开发神经元化量表，这是一组用于ImageJ的Java插件，用于执行半自动数据分析。大约75％的人类MR基因在果蝇中具有对应物，逐序与在大脑中表现出相似的功能相似。我们将筛选果蝇MR基因的一部分，我们认为这是在体外揭示神经元形态和可塑性缺陷的主要候选者。在并行研究中，我们将重点关注“ Filagree”表型，这是由于细胞骨架蛋白的遗传丧失而在体外的神经突生长模式，并筛选出使该表型正常化的化合物。一起，表型和纠正化学剂的筛选应为将该测定法作为阶梯式阶段，以作为MR疾病的药物发现和发育的垫脚石。公共卫生相关性：我们的长期目标是用解决脑发育的潜在异常的药物来治疗智力低下的障碍。提出的实验是朝着该目标迈出的重要一步。