Optimization of a Chemokine Receptor Antagonist Peptide as a Synapse Protecting Treatment for Neurodegeneration in Alzheimer's Disease

7.项目摘要AD 作为对PAS-19-319的回应，Creative Bio-Peptides，Inc.提出了一种新的治疗方法， 通过阻断促进突触的多种趋化因子受体来恢复阿尔茨海默病（AD）中的突触 失去并抑制其再生。AD中的功能损害由神经元棘的丧失和 树突，之前和独立的神经元死亡。Cofilin-肌动蛋白杆（杆）是肌动蛋白的1：1复合物， 其形成与细胞朊病毒蛋白（PrPC）和NADPH氧化酶（NOX）依赖性相关的cofilin 信号通路，并代表早期AD病理学。在高能条件下， 和氧化应激，如发生在神经炎症，并导致神经突远端萎缩。突触功能 与来自相同神经元和杆的无杆神经突相比， 在AD动物模型和人类AD脑中显著增加。相反， AD小鼠模型通过减少神经元中的cofilin杆而得到缓解。Cofilin在树突状细胞中起重要作用 棘动力学和受体运输以及cofilin进入杆的隔离对突触的形成是有害的。 功能我们的初步数据表明，新的口服，稳定和快速脑渗透肽类似物的 临床应用多趋化因子受体拮抗剂（mCRA）DAPTA（Dala 1-肽T-酰胺）抑制形成 Aβd/t（1 nM）诱导的cofilin-actin杆，具有神经保护作用。DAPTA减少了小胶质细胞的激活， 齿状回，防止NBM损伤的老年动物皮质神经元丢失，并促进稳健的发芽 轴突和突触再生的过程。在NIH对受试者进行的多项II期试验中， HIV相关的神经认知障碍（HAND），DAPTA使脑功能扫描正常化， 通过与预防cofilin杆相关的趋化因子受体阻断机制进行的2期试验中的认知缺陷 形成和保护突触。趋化因子阻断的突触和轴突延伸作用是 最近还显示，马拉韦罗在脑损伤中证实趋化因子受体作为翻译靶点， 药物开发DAPTA在600多人中是安全的，有些人长达十年，但并不稳定 作为鼻喷雾制剂。我们花了很多年的时间来创造新的稳定的DAPTA口服类似物， 现在提出优化用于突触保护和恢复的先导口服肽 通过测定四种口服肽抑制Aβd/t诱导的cofilin形成的EC 50值， 在原代小鼠海马神经元培养物中，与批准的CRA的maraviroc和AMD 3100相比， 我们将进一步优化肽在Aβd/t处理的神经元中的神经保护作用， 突触形态的形态和结构评估。一旦我们确定了优化的 肽，我们将确定安全性和毒代动力学特征，并确认脑进入作为未来IND的前奏， 赋能研究。

7. Project Summary AD In response to PAS-19-319, Creative Bio-Peptides, Inc. proposes a novel therapeutic approach to protect and restore synapses in Alzheimer’s Disease (AD) by blocking multiple chemokine receptors that promote synapse loss and inhibit their regeneration. Functional impairment in AD results from loss of neuronal spines and dendrites, preceding and independent of neuronal death. Cofilin-actin rods (rods) are a 1:1 complex of actin and cofilin whose formation is linked to a cellular prion protein (PrPC) and NADPH oxidase (NOX)-dependent signaling pathway and represents an early AD pathology. Rods form in neurites under conditions of energetic and oxidative stress, such as occur in neuroinflammation, and lead to neurite distal atrophy. Synapse function declines in neurites in which rods have formed compared neurites without rods from the same neuron and rods are significantly increased in animal models of AD and in human AD brain. Conversely, cognitive deficits in mouse models of AD are alleviated by decreasing cofilin rods in neurons. Cofilin plays important roles in dendritic spine dynamics and receptor trafficking and the sequestering of cofilin into rods is detrimental to synaptic function. Our preliminary data shows that new oral, stable and rapidly brain penetrant peptide analogs of the clinical use multi-chemokine receptor antagonist (mCRA) DAPTA (Dala1-peptide T-amide) inhibit the formation of Aβd/t (1 nM)-induced cofilin-actin rods and are neuroprotective. DAPTA reduced microglial activation in the dentate gyrus, prevented cortical neuronal loss in NBM-lesioned aged animals and promoted robust sprouting of axons and synapse regeneration in animals. In multiple phase 2 trials conducted by the NIH on subjects with HIV-associated neurocognitive disorders (HAND), DAPTA normalized functional brain scans and reversed cognitive deficits in phase 2 trials by chemokine receptor blocking mechanisms related to preventing cofilin rod formation and protecting synapses. The synapse and neurite extending effects of chemokine blockade were recently also shown for maraviroc in brain injuries confirming chemokine receptors as translational targets for drug development. DAPTA was safe in over 600 persons, some for as long as ten years however was not stable as a nasal spray formulation. It took us many years to create new stable oral analogs of DAPTA with better brain entry and long half-life and now propose to optimize a lead oral peptide for synapse protecting and restoring benefits in AD by determining the EC50 values for four oral peptides to inhibit formation of Aβd/t-induced cofilin rods compared to approved CRA’s maraviroc and AMD3100 in primary mouse hippocampal neuronal cultures. We will further optimize the neuroprotective effects of peptides in Aβd/t-treated neurons through quantifiable morphological and architectural assessments of synapse morphology. Once we have identified the optimized peptide, we will determine the safety and toxicokinetic profile and confirm brain entry as a prelude to future IND- enabling studies.