Identification and confirmation of blood-brain barrier (BBB) permeability of chemical enhancers of nerve growth factor-dependent neurite outgrowth.

 描述(由申请人提供)：神经细胞死亡是一种与许多神经退行性疾病相关的肉眼神经病理特征。在阿尔茨海默病(AD)的病例中，轴突和树突建立的突触连接的恶化与AD影响的大脑中心失去神经营养支持有关。一些实验策略和发现方案被用作逆转对神经元结构的影响的手段，但许多都没有转化为成功的治疗方法。神经生长因子(NGF)的直接应用被证明可以促进退行性神经元的形态和功能的恢复，这表明一种增强神经营养因子功能的治疗方法可以阻止或逆转AD和其他神经退行性疾病的影响。我们的中心假设是，增强神经营养因子活性的小分子特别适合于研究类药物增强神经肽活性的基本机制，以确定潜在的靶点，从而开发出许多与年龄相关的神经退行性疾病的新疗法。因此，我们合成并测试了马鞭草的天然产物马鞭草酮(Vc)和几种在神经细胞模型中促进轴突生长(NOG)的衍生物。此外，我们利用VC的二氢查尔酮骨架作为计算模型中的模板，以确定具有NGF依赖的NOG促进活性和神经保护特性的小分子B355252。合成了毒性轮廓得到改善的小分子衍生物。然而，特区的研究并没有在复合效力方面有所改善。在这个项目中，我们建议鉴定具有不同于B355252的新型支架的化合物，这些支架与NGF协同作用，通过实施基于表型图像的屏幕来增强NOG。此外，我们将开发和验证体外血脑通透性分析，以测试来自屏幕的类似物和HIT的跨越血脑屏障的可能性，并启动对先导化合物信号机制的研究，作为未来体内化合物研究的前奏。

 DESCRIPTION (provided by applicant): Nerve cell death is a gross neuropathologic feature associated with many neurodegenerative diseases. In the case of Alzheimer's disease (AD), deterioration of synaptic connections made by axons and dendritic processes has been linked to the loss of neurotrophic support in the brain centers affected by AD. Several experimental strategies and discovery schemes have been employed as a means to reverse the effects on neuronal architecture but many have not translated into successful therapies. Direct application of nerve growth factor (NGF) has been shown to augment morphological and sometimes functional recovery of degenerating neurons suggesting that a therapeutic approach that enhances the function of neurotrophins could halt or reverse the effects of AD and other neurodegenerative diseases. Our central hypothesis is that small molecules that enhance the activities of neurotrophins are uniquely suited to study the fundamental mechanisms that underlie activity potentiation of neuropeptides by drug-like chemicals in order to identify potentil targets that could lead to development of novel therapeutics for many age-related neurodegenerative diseases. Consequently, we have synthesized and tested Verbenachalcone (VC), a natural product from Verbena litoralis, and several derivatives that promote neurite outgrowth (NOG) in neuronal cell models. In addition, we utilized the dihydrochalcone backbone of VC as a template in a computational model to identify a small molecule B355252 with NGF-dependent NOG promoting activity and neuroprotective properties. Derivatives of the small molecule with improved toxicity profile have been synthesized. However, the SAR studies have not yielded improvements in compound potency. In this project we propose to identify compounds with novel scaffolds different from that of B355252, which synergize with NGF to enhance NOG by implementing a phenotypic image-based screen. In addition, we will develop and validate an in vitro blood- brain permeability assay to test the analogs and hits from the screen for potential to cross the blood-brain barrier and initiate studies on the signaling mechanisms of lead compounds as a prelude for future in vivo compound studies.