Tau Protein Aggregation Inhibitors for Tauopathies

描述（由申请人提供）：阿尔茨海默病（AD）的特征在于由不溶性β-淀粉样蛋白（A？）组成的脑淀粉样斑块，和含有聚集的tau蛋白的神经纤维缠结（NFT）。AD药物发现的努力主要集中在减少大脑A？水平，少得多的重点对tau导向的战略。ProteoTech Inc.已经开发了许多不同的体外筛选技术和细胞模型，鉴定了新的淀粉样变性的有效抑制剂。我们已经设计、合成并测试了一类新的化学实体（NCE），其由含有由连接体区域间隔的多羟基化芳环的小分子（200-400 MW）组成。来自我们的I期SBIR研究的结果已经鉴定了十（10）种具有在体外抑制/破坏tau蛋白原纤维形成的强效力的先导小分子化合物。这一发现得到了几个国家的证实。 这些方法包括硫磺素S荧光测定法、CD光谱法、电子显微镜法和基于细胞的测定法。我们假设，特定的铅多羟基化芳香族化合物也可以作为直接抑制剂的tau蛋白病的小鼠模型中的tau蛋白聚集/纤维形成。这些化合物被认为具有作为AD和相关tau蛋白病的新治疗剂的巨大潜力。我们的第二阶段SBIR项目的主要目标是在相关的tau蛋白病小鼠模型中鉴定能够减少tau蛋白相关病理学并改善tau蛋白诱导的行为缺陷的先导多羟基化芳香族化合物。在具体目标1中，我们将评估10种先导小分子化合物的可药性、血脑屏障渗透性、药代动力学（PK）特征和小鼠急性毒性。将选择在小鼠中具有最佳脑渗透性、外周PK、可药用性和耐受性的三种先导小分子化合物用于目的2中的动物研究。在具体目标2中，我们将测试三种最佳先导化合物（选自目标1）在表达人P301 S突变tau蛋白的转基因小鼠模型中的体内功效。我们将用三种化合物以两种给药途径之一（口服或s.c.根据目标1研究确定），每种化合物3个剂量，持续6个月（从3月龄开始）。这些化合物在减少tau聚集/NFT形成、改善tau相关记忆缺陷和改善CSF tau生物标志物谱中的有效性将使用染色和定量免疫组织化学、蛋白质印迹、ELISA和行为测试（包括Morris水迷宫测试）来确定。该II期SBIR项目将产生用于治疗AD和其他tau蛋白病中tau聚集的临床前候选药物（和备用药物）。

DESCRIPTION (provided by applicant): Alzheimer's disease (AD) is characterized by brain amyloid plaques consisting of insoluble beta-amyloid protein (A?), and neurofibrillary tangles (NFTs) containing aggregated tau protein. AD drug discovery efforts have been largely focused on reducing brain A? levels, with much less emphasis on tau-directed strategies. ProteoTech Inc. has developed a number of different in vitro screening technologies and cellular models that identified new potent inhibitors of amyloidoses. We have designed, synthesized and tested a class of new chemical entities (NCE) consisting of small molecules (200-400 MW) containing polyhydroxylated aromatic rings spaced by a linker region. Results from our Phase I SBIR studies have identified ten (10) lead small molecule compounds that possess strong potency to inhibit/disrupt tau protein fibril formation in vitro. This discovery has been confirmed by several independent methodologies, including Thioflavin S fluorometry, CD spectroscopy, electron microscopy and cell-based assays. We hypothesize that specific lead polyhydroxylated aromatic compounds can also serve as direct inhibitors of tau aggregation/fibrillogenesis in mouse models of tauopathies. These compounds are believed to possess great potential as new therapeutic agents for AD and related tauopathies. The major objective of our Phase II SBIR project is to identify lead polyhydroxylated aromatic compounds in a relevant mouse model of tauopathy that have the ability to reduce tau-related pathology and to improve tau-induced behavioral deficits. In Specific Aim 1, we will assess the 10 lead small molecule compounds for their drugability, blood-brain-barrier penetration, pharmacokinetic (PK) profiles, and acute toxicity in mice. Three lead small molecule compounds that possess the best brain penetration, peripheral PK, drugability and tolerance in mice will be selected for animal studies in Aim 2. In Specific Aim 2, we will test the three best lead compounds (selected from Aim 1) for their in vivo efficacy in a transgenic mouse model expressing the human P301S mutant tau protein. We will treat mice with three compounds with one of two administration routes (orally or s.c. to be determined from Aim 1 studies) at 3 doses for each compound for 6 months (starting at 3 months of age). The effectiveness of these compounds in reducing tau aggregation/NFT formation, improving tau-related memory deficits, and improving CSF tau biomarker profiles will be determined using staining and quantitative immunohistochemistry, western blotting, ELISAs and behavioral testing including the Morris water maze test. This Phase II SBIR project will lead to a pre-clinical candidate (and back-up) for the treatment of tau aggregation in AD and other tauopathies.