PTPRD phosphatase inhibitors for stimulant use disorders

项目摘要/摘要 阿尔茨海默病(AD)的致病因素来自遗传学和环境因素。 影响因素包括饮食中黄酮醇和黄酮类的摄入量[4-8]。富含高密度脂蛋白的神经原纤维缠结(NFT) 磷酸化tau蛋白[10]是AD神经病理的显著特征。NFT密度与 阿尔茨海默病的程度[15][18]，并受载脂蛋白E和PTPRD基因变异的影响[3]。 改变tau/NFT病理生理学的一种方法是减少激活Tau/NFT的蛋白激酶的活性。 磷酸化tau。糖原合成酶α和β是重要的tau磷酸化因子 [19]。已知gsk3α和gsk3β通过自身酪氨酸(pY279和pY216)的磷酸化而激活 酪氨酸激酶[20][21，22]。提高酪氨酸磷酸酶(S)的活性，使其脱磷和还原 因此，脑内Gsk3α和Gsk3β的活性为减轻AD的tau病理提供了一条新的途径。 证据(在我们之前的NIA补充支持中得到了很大的发展)现在支持以下作用：a)受体 蛋白酪氨酸磷酸酶是磷酸(Py)GSK3α的关键生理磷酸酶 和Gsk3β和一个减少病理性AD tau过度磷酸化的新靶点，b)黄酮醇为先导 复合PTPRD阳性变构调节剂(PAM)，可增加所需的PTPRD活性和c) 天然产物和新的黄酮醇类似物的结构活性关系支持以下可能性 进一步的改进将提供新的候选药物。我们将加强这一证据，并朝着 通过测试a)8位取代和其他黄酮醇类似物将显示的假设进行翻译 增强Gsk3β/Gsk3αpTPrD去磷酸化的正变构调节 将显示与相关磷酸酶活性有关的特异性c)最佳类似物将显示改进 硅胶和活体中的类药物特性。这些属性中的每一个都将允许我们开发和选择改进的、 特定的PTPRD PAM，可以减少衰老过程中AD缺陷的进展。 我们将验证这些假设，并通过以下几种方式支持PTPRD PAM的开发和翻译：1) 我们将合成和测试新的黄酮醇类似物作为改进的PTPRD PAM，在体外测试这些结构， 提炼我们的硅胶模型并基于这些结果提名/合成/测试新结构， 检测目前与其他PTPRD底物磷酸肽和非靶点作用位点的特异性 市场上销售的药品。我们将在体内测试最有希望的PTPRD PAM的大体、组织学或行为学 毒性、生物分布(包括大脑)和靶子接触的证据。我们将开始测试最好的 PTPRD表达降低或不降低的3xTg-AD小鼠的候选研究。这项工作将推动我们的 了解AD的病理生理学，验证PTPRD正变构调节和 为制定可预防和/或治疗AD的关键方面的干预措施提供基础。

Project Summary/Abstract Alzheimer’s disease (AD) receives pathogenic contributions from genetics [1, 2] and from environmental influences that include dietary intake of flavonols > flavones [4-8]. Neurofibrillary tangles (NFTs) rich in hyper- phosphorylated tau protein [10] are prominent features of AD neuropathology. NFT densities correlate well with the degree of AD dementia [15] [18] and are influenced by variation in the ApoE and PTPRD genes [3]. One approach to altering tau/NFT pathophysiology is to reduce activities of the kinases that hyper- phosphorylate tau. The glycogen synthase kinases GSK3α and GSK3β are prominent tau phosphorylators [19]. GSK3α and GSK3β are activated by phosphorylation of their own tyrosines (pY279 and pY216) by known tyrosine kinases [20] [21, 22]. Increasing activity of tyrosine phosphatase(s) that dephosphorylate and reduce activities of brain GSK3α and GSK3β thus provides a novel approach to reducing tau pathology in AD. Evidence (much developed during our prior NIA supplement support) now supports roles for: a) the receptor type protein tyrosine phosphatase PTPRD as both a key physiological phosphatase for phospho (pY) GSK3α and GSK3β and a novel target for decreasing pathological AD tau hyperphosphorylation, b) flavonols as lead compound PTPRD positive allosteric modulators (PAMs) that increase this desired PTPRD activity and c) structure activity relationships for natural product and novel flavonol analogs that supports the likelihood that further modifications will provide novel drug candidates. We will enhance this evidence and move toward translation by testing hypotheses that a) 8- position-substituted and other flavonol analogs will display enhanced positive allosteric modulation of PTPRD dephosphorylation of GSK3β/GSK3α b) this enhancement will display specificity with respect to activities at related phosphatases c) optimal analogs will display improved drug-like properties in silico and in vivo. Each of these attributes will allow us to develop and select improved, specific PTPRD PAMs that can reduce progression to AD deficits during aging. We will test these hypothesis and support development and translation of PTPRD PAMs in several ways: 1) We will synthesize and test novel flavonol analogs as improved PTPRD PAMs, testing these structures in vitro, refining our in silico models and nominating/synthesizing/testing new structures on the basis of these results, testing specificities vs other PTPRD substrate phosphopeptides and off-target sites of action of currently marketed drugs. We will test the most promising PTPRD PAMs in vivo for gross, histological or behavioral toxicities, biodistribution (including brain) and evidence for target engagement. We will begin testing of the best candidates in aging 3xTg-AD mice with or without reduced PTPRD expression. This work will advance our understanding of AD pathophysiology, validate novel approaches to PTPRD positive allosteric modulation and provide a basis for development of interventions that can prevent and/or treat key aspects of AD.