PKC Modulators for the Treatment of Alzheimer's disease

描述(申请人提供)：越来越多的人达成共识，认为阿尔茨海默病(AD)病理生理学中的关键事件是淀粉样β蛋白(Abeta)的过度产生。如果这一提法是正确的，那么有三种主要的策略可以阻断病理性的级联反应：抑制β-分泌酶、抑制伽马-分泌酶或增强α-分泌酶。直觉上，如果Abeta是罪魁祸首，减少多肽的生成是最有希望的方法。β-分泌酶和伽马-分泌酶都是产生完整的Abeta所必需的，而α-分泌酶在Abeta结构域内裂解，阻止其完整释放。制药业在开发β-和伽马分泌酶抑制剂方面投入了大量资金，尽管目前还没有一种药物在人体试验中成功。我们提出了一种基于第三种方法的策略，即增强α-分泌酶活性。我们增强α-分泌酶活性的方法包括调节蛋白激酶C(PKC)，这已被确凿地与许多实验室的α-分泌酶调节联系在一起。在这方面，我们最近已经证明了结构新颖的PKC激活剂8-(1-Decynyl)-苯内酰胺能够逆转K+通道缺陷，并增强AD细胞中α-分泌酶产物sAPPalpha的产生。更重要的是，在体内测试时，这种苯唑内酰胺显著增加了APP[V7171]转基因小鼠大脑中sAPPalpha的数量，降低了Abeta40的含量。鉴于8-(1-癸基)-苯唑内酰胺取得了良好的动物实验数据，以及我们在苯内酰胺(BL)的SAR方面的长期经验，我们建议进行一项高度集中的研究，旨在确定可以作为治疗AD的临床候选药物的最佳苯唑内坦类似物。为实现这一目标，我们的目标如下： 1.使用分子模拟工具进行化合物设计和新型BLS的化学合成，目的是优化对α-分泌酶活性的影响，同时减少任何可能的促肿瘤活性；这项工作的大部分将集中在改变侧链附件的性质； 2.开展体外研究，确定新类似物的生物活性。筛选所有化合物作为PKC激活剂的活性。测试选定的有效PKC激活剂(EC50至少50 NM)对sAPPalpha和Abeta 1-40和1-42水平的影响。测试有效促进sAPPalpha产生的化合物以促进肿瘤的作用； 3.对于来自Aim 2的最佳化合物，在三重转基因小鼠中进行研究，以确定对体内Abeta和sAPPalpha水平和斑块形成的影响。

DESCRIPTION (provided by applicant): There is a growing consensus that the pivotal event in the pathophysiology of Alzheimer's disease (AD) is overproduction of amyloid beta peptide (Abeta). If this formulation is correct, then there are three primary strategies for interrupting the pathologic cascade: inhibiting beta-secretase, inhibiting gamma-secretase, or augmenting alpha-secretase. Intuitively, if Abeta is the culprit, reducing the generation of the peptide is the most promising approach. Both beta- and gamma-secretase are necessary for generation of intact Abeta, while alpha-secretase cleaves within the Abeta domain, preventing its release intact. The pharmaceutical industry has invested heavily in the development of beta- and gamma-secretase inhibitors, though none has yet succeeded in human trials. We propose a strategy based on the third approach, augmenting alpha-secretase activity. Our approach to augmenting alpha-secretase activity involves modulating protein kinase C (PKC), which has conclusively been linked to regulation of alpha-secretase in a number of laboratories. In this regard, we have shown recently that the structurally novel PKC activator, 8-(1-decynyl)-benzolactam, is able to reverse K+ channels defects and to enhance the production of the alpha-secretase product sAPPalpha in AD cells. More importantly, when tested in vivo, this benzolactam significantly increased the amount of sAPPalpha and reduced Abeta40 in the brains of APP[V7171] transgenic mice. Given the promising animal data achieved with the 8-(1-decynyl)-benzolactam and our long experience in the SAR of the benzolactams (BL), we propose to conduct a highly focused study aimed at defining the best benzolactam analog that can serve as a clinical candidate for the treatment of AD. To achieve this goal, our aims become the following: 1. Conduct both compound design using molecular modeling tools and the chemical synthesis of novel BLs with the aim to optimize effects on alpha-secretase activity while diminishing any possible tumor promoting activity; Much of this work will focus on altering the nature of the side chain appendages; 2. Carry out in vitro studies to define the biological activity of new analogs. Screen all compounds for activity as PKC activators. Test selected potent PKC activators (EC50 at least 50 nM) on levels of sAPPalpha and Abeta 1-40 and 1-42. Test compounds effective in enhancing sAPPalpha production for tumor promoting effects; 3. For the best compounds from Aim 2, perform studies in triple transgenic mice to ascertain effects on Abeta and sAPPalpha levels and plaque formation in vivo.