Therapeutics targeting TDP-43 to treat Alzheimer's disease and related disorders

TDP-43是阿尔茨海默病（AD）中的一种混合蛋白病，AD-TDP，基于大量流行病学研究， AD患者中TDP-43内含物与认知下降相关的数据。TDP-43相关AD已被 被称为边缘优势年龄相关TDP-43脑病（LATE）以及其它首字母缩写， 这是TDP-43在AD（AD-TDP）中新认识到的重要性的基础。AD是最常见的原因 中晚期认知障碍和痴呆症，困扰着全球约3000万人。 广泛回顾临床和病理学研究，TDP-43蛋白质病与遗忘有关， 老年痴呆综合症。归因风险的统计分析表明，TDP-43 相关AD是一个主要的公共卫生问题，占临床诊断AD病例的20 痴呆这种TDP-43蛋白病是一种不同于其他TDP-43蛋白病的临床和病理实体 也可以用TDP-43靶向治疗治疗的相关疾病，如肌萎缩侧索硬化症， 硬化症（ALS）和某些形式的额颞叶变性（FTLD-TDP）。因此，成功 该项目的完成有可能确定基于TDP-43的治疗方法，用于治疗其他 TDP-43起主要和致病作用的疾病。我们发现了一些小分子， 以抑制RNA与TDP-43结合并防止TDP-43聚集的方式，具有活性 提示在三种模型中的治疗效果：（1）人野生型和突变型TDP-43，其表达于 果蝇，（2）来自C9orf 72患者来源的iPSC的诱导运动神经元（iMN），和（3）表达C9orf 72的小鼠。 人TDP-43（Thy1启动子）。来自2-D NMR研究和计算对接分析的证据 表明这些抑制剂与核糖核苷酸识别基序RRM2结合，该基序含有一种 参与与RRM1的关键和功能相关的盐桥的氨基酸。最近的PET成像研究 描述了一种代谢标志物，可根据FDG比率选择AD-TDP患者进行临床试验 在大脑的不同区域成像。在这个项目中，我们寻求发现，验证和开发新的小- 与TDP-43结合的核酸分子抑制剂和TDP-43聚集抑制剂以治疗AD-TDP。目的 1是新型TDP-43配体的体外效力和药物样性质的优化，包括渗透 以及可接受的半衰期和安全性措施，使用一套全面的药物组合， 行业标准分析和标准。目的2涉及使用转染的hTDP-43的靶接合研究。 HEK293T细胞，来自iPSC的患者来源的诱导运动神经元，动态光散射分析 聚集和结合到TDP-43中的配体的X射线晶体学。目的3是在动物模型中进行评价， TDP-43病理学，最初使用Thy1启动子，随后使用基于hTDP-43的小鼠模型， 在没有运动缺陷的情况下表现出认知障碍。目标4包括国家自主研发能力研究， 放大合成、多物种PK和啮齿动物毒性。

TDP-43 is a mixed proteinopapthy in Alzheimer’s disease (AD), AD-TDP, based on substantial epidemiological data correlating TDP-43 inclusions with cognitive decline in AD patients. TDP-43 associated AD has been termed as limbic-predominant age-related TDP-43 encephalopathy (LATE) as well as other acronyms, underlying the newly-recognized importance of TDP-43 in AD (AD-TDP). AD is the most common cause of mid- to late-life cognitive impairment and dementia, afflicting ~30 million people worldwide Based on an extensive review of clinical and pathological studies, TDP-43 proteinopathy is associated with an amnestic dementia syndrome that occurs in older adults. A statistical analysis of attributable risk suggests that TDP-43 associated AD is a major public health issue accounting for up to 20% of cases of clinically diagnosed AD dementia. This TDP-43 proteinopathy is a distinct clinical and pathological entity from other TDP-43 associated diseases that may also be treatable with a TDP-43 targeted therapy, such as amyotrophic lateral sclerosis (ALS) and certain forms of frontotemporal lobar degeneration (FTLD-TDP). Therefore, successful completion of this project has the potential to identify TDP-43-based therapeutics for the treatment of other diseases where TDP-43 plays a major and causative role. We have discovered small molecules that bind to TDP-43 in such a way as to inhibit binding of RNA to TDP-43 and prevent TDP-43 aggregation, with activity suggestive of a therapeutic effect in three models: (1) human wild-type and mutant TDP-43 expressed in Drosophila, (2) induced motor neurons (iMNs) from C9orf72 patient-derived iPSCs, and (3) mice expressing human TDP-43 (Thy1 promotor). Evidence from 2-D NMR studies and computational docking analysis suggests that these inhibitors are binding to ribonucleotide recognition motif RRM2 which contains one of the amino acids involved in a critical and functionally-relevant salt bridge with RRM1. A recent PET imaging study describes a metabolic marker to potentially select AD-TDP patients for clinical trials based on ratios of FDG imaging in different regions of the brain. In this project we seek to discover, validate and develop new small- molecule inhibitors of nucleic acid binding to TDP-43 and TDP-43 aggregation inhibitors to treat AD-TDP. Aim 1 is the optimization of in vitro potency and drug-like properties of novel TDP-43 ligands including penetration into the brain and acceptable half-life and safety measures using a comprehensive battery of pharmaceutical industry-standard assays and criteria. Aim 2 involves target engagement studies using hTDP-43 transfected in HEK293T cells, patient-derived induced motor neurons from iPSCs, dynamic light scattering analysis of aggregation, and X-ray crystallography of ligands bound into TDP-43. Aim 3 is evaluation in animal models of TDP-43 pathology, initially using a Thy1 promoter followed by a hTDP-43 based mouse model that demonstrates cognitive impairment in the absence of locomotor deficits. Aim 4 includes IND-enabling studies, scale-up synthesis, multi-species PK and rodent toxicity.