Novel Disease-modifying Small Molecules for Treatment of Alzheimer's Disease”

项目总结 阿尔茨海默病(AD)是退伍军人事务部(VA)中最常见的痴呆症类型 医疗系统。目前还没有可用的治疗方法来减缓或阻止AD的神经退变过程。 我的研究计划有一个持续的兴趣，即开发支持IND的AD新治疗策略。 我们重点研究了一种新的改善认知功能的靶点，称为突触素1(Synj1)和几条线 来自我的研究小组以及其他研究小组的数据表明，Synj1减少对AD的有益影响。Synj1是 大脑和突触中的主要的二磷酸肌醇(PIP2)降解酶。增加了synj1 阿尔茨海默病的表达和活动与认知功能下降和病理过程有关，如 早期内小体增大和载脂蛋白E4导致的认知障碍。已鉴定的synj1基因多态 早发和晚发家族性AD受试者与发病年龄和synj1表达增加相关 与认知缺陷和局部细胞功能障碍相关。此外，不溶性Synj1增加并 聚集在阿尔茨海默病患者大脑中斑块相关的营养不良神经突起和神经原纤维缠结周围， 尤其是在APOE4+AD的大脑中。基因敲除synj1可减轻AD相关的病理改变和 行为缺陷。具体地说，下调synj1与升高的PIP2水平可以保护免受寡聚体Ab. 诱导对突触完整性的毒性效应，并通过内切酶途径促进Aβ的清除。 部分敲除synj1逆转载脂蛋白E4诱导的溶酶体缺陷并改善载脂蛋白E4的行为缺陷 敲入鼠模型，以及家族性阿尔茨海默病(FAD)和唐氏综合征的多种动物模型。向下- Synj1的调节也挽救了轻度创伤性脑损伤(MTBI)诱导的PIP2调节失调，并防止 Tau蛋白过度磷酸化的研究进展。最近，我们收集的数据表明synj1减少的作用 在调节阿尔茨海默病的小胶质细胞功能和神经炎症方面发挥重要作用。总而言之，这些研究支持有益的 Synj1减少在AD中的作用。我们一直在开发具有降低synj1的新型小分子支架。 并确定了一种美国食品和药物管理局批准的药物(尼莫地平)，它可以降低血管内皮细胞中Synj1蛋白和Aβ水平 体外和体内。它还在短期治疗中改善了AD模型小鼠的认知功能。然而， 长期服用尼莫地平未能降低脑Aβ42水平(特别是不溶性部分)，或 改善认知功能。然后，我们利用药物化学开发了尼莫地平结构类似物。 增强其降低synj1效应(靶上效应)和降低其钙通道活性(OFF-TRANSE)的方法 靶向副作用)。两个尼莫地平衍生物：SynaptoCpd#9和CPD#6从点击到领先中选择 筛选和先导优化，显示出改善的口服生物利用度和增加的长期体内疗效 在家族性和散发性AD小鼠模型中与其母化合物尼莫地平进行比较 (退伍军人事务部提交的PCT/US2018/062020)。这些发现在以下层面奠定了基础 使用Synj1降低剂治疗AD的概念验证(PoC)。该项目的目标是执行 两种先导化合物在IND应用和I期临床试验准备中的IND使能研究 学习。我们将：1)进行SynaptoCpd#9和CPD#6的体外ADME和体内DMPK研究(目标1)； 随后进行2)药效学研究(急性给药范围研究和慢性疗效研究)以及 探索性毒性研究(目标2)；3)开发SynaptoCpd的靶结合和替代生物标记物 #9和CPD#6(目标3)使用先前存储的SynaptoCpd#9和CPD治疗小鼠的血浆样本 #6(预防和治疗范例)，以及从DMPK研究中收集的新样本 (目标1)和钯/毒性研究(目标2)。本应用程序的目标是促进下一步IND应用程序 最终目标是过渡到临床研究和我们的新型AD疗法的商业化。

PROJECT SUMMARY Alzheimer's disease (AD) is the most frequently diagnosed type of dementia within the Veterans Affairs (VA) Medical System. Currently no treatment is available to slow down or stop neurodegenerative processes of AD. My research program has an ongoing interest of developing IND-enabling novel therapeutic strategies for AD. We focus on studying a novel target to improve cognitive function, called synaptojanin 1 (synj1) and several lines of data from my research group as well as others suggest beneficial effects of synj1 reduction in AD. Synj1 is the main phosphoinositol bisphosphate (PIP2) degrading enzyme in the brain and synapses. Increased synj1 expression and activities have been associated with cognitive decline and pathological processes of AD, such as enlargement of early endosomes and ApoE4-induced cognitive deficits. The synj1 polymorphisms identified in early- and late-onset familial AD subjects are associated with age of onset, and increased synj1 expression correlates with cognitive deficits and place cell dysfunction. In addition, insoluble synj1 is increased and accumulated around plaque-associated dystrophic neurites and neurofibrillary tangles in AD human brains, particularly in APOE4+ AD brains. Genetic knockdown of synj1 attenuates AD-related pathological changes and behavioral deficits. Specifically, down-regulation of synj1 with elevated PIP2 levels protect against oligomer Ab- induced toxic effects on synaptic integrity and promotes Aβ clearance through the endo-lysosomal pathway. Partial knockdown of synj1 reverses ApoE4-induced lysosomal defects and improves behavior deficits in ApoE4 knock-in mouse models, as well as multiple animal models of familial AD (FAD) and Down syndrome. Down- regulation of synj1 also rescues mild traumatic brain injury (mTBI)-induced PIP2 dysregulation and prevents development of tau hyper-phosphorylation. Recently, we have gathered data suggesting a role of synj1 reduction in modulating microglial function and neuro-inflammation in AD. Together, these studies support beneficial effects of synj1 reduction in AD. We have been developing scaffolds of novel small molecules with synj1-lowering capabilities and identified an FDA-approved drug (nimodipine) that reduces synj1 protein and Aβ levels both in vitro and in vivo. It also improved cognitive function in AD mouse models in short-term treatment. However, chronic administration of nimodipine failed to reduce brain Aβ42 levels (particularly insoluble fractions), or to improve cognitive function. We then developed nimodipine structural analogs using medicinal chemistry approaches to potentiate its synj1-lowering effects (on-target effects) and reduce its calcium channel activity (off- target side effects). Two nimodipine derivatives: SynaptoCpd #9 and Cpd #6 were selected from hit-to-lead screening and lead optimization, exhibiting improved oral bioavailability and increased long-term in vivo efficacy when compared to their parent compound nimodipine using both familial and sporadic AD mouse models (PCT/US2018/062020 filed by the VA Tech Transfer). These findings establish the foundation at the level of Proof-of-Concept (PoC) to treat AD with synj1-lowering agents. The objectives of the project are to perform the IND-enabling studies of two lead compounds in preparation of the IND application and phase I clinical trial studies. We will: 1) perform in vitro ADME and in vivo DMPK studies of SynaptoCpd #9 and Cpd #6 (Aim 1); followed by 2) pharmacodynamic studies (acute dosing range finding and chronic efficacy studies) as well as exploratory toxicity studies (Aim 2); 3) develop target engagement and surrogate biomarkers for SynaptoCpd #9 and Cpd #6 (Aim 3) using previously stored plasma samples from mice treated with SynaptoCpd #9 and Cpd #6 (preventive and therapeutic treatment paradigms), as well as new samples collected from DMPK studies (Aim 1) and PD/toxicity studies (Aim 2). The goals of this application aim to facilitate next step IND application with ultimate goals of transitioning into clinical studies and the commercialization of our novel AD therapies.