基于化学信息学技术从天然产物中发现并设计新型HIF-1α/pVHL蛋白-蛋白相互作用抑制剂

Increaseing HIF-1α concentration after ischemic stroke cells can protect damaged nerves, reduce disability mortality. HIF-1α is ubiquitinated and degradated by the von Hippel−Lindau protein (pVHL), the substrate recognition subunit of an E3 ligase. However, the strategy of finding HIF-1α/pVHL protein-protein interaction (PPI) inhibitors is ineffective resulting in few scaffolds. The reason is that, unlike the traditional kinase targets, PPI, with larger binding pockets, more complicated interaction forces and not to be screened by conventional means targeting to small molecules. The project will construct novel pharmacophore model based on multi-protein structures and cascade docking to reduce the high false-positive rate. To improve the source of the database’s quality, the project will build up natural product database and discover novel leads from it. To solve the problem of the PPI inhibitors with the source of low quality, the project will focus on the source of natural products to build up highly target adaptation of natural products database and find novel scaffolds. Then, we will use the chemical means of drug design and synthesis to define HIF-1α/pVHL PPI inhibitors with clear target activity. Multiple methods will be applied for the mechanism study. Under this new research platform, novel HIF-1α/pVHL PPI inhibitors will be discovered and designed.

提高HIF-1α在脑中风后缺血脑细胞中的蛋白浓度，可保护受损的神经、降低致残致死率。HIF-1α主要由pVHL调控代谢。目前HIF-1α/pVHL蛋白-蛋白相互作用的研究策略单一、抑制剂种类较少。这是因为蛋白-蛋白相互作用不同于传统的激酶等靶点，其具有口袋大、作用力复杂、无法采用常规筛选小分子的手段等特点。我们以化学信息学为指导，采用基于多晶体结构的新型药效团和级联对接等手段，解决常规筛选策略在有高度柔性的蛋白-蛋白相互作用中筛选易产生高假阳性率的问题。为解决蛋白-蛋白相互作用抑制剂来源质量不高问题，本项目以天然产物为来源，构建高度靶标适配性的天然产物数据库；发现新型骨架并运用药物化学手段设计合成有明确靶标活性的HIF-1α/pVHL蛋白-蛋白相互作用抑制剂。通过生物机制研究，确保研究结果合理、可靠，从而建立新型HIF-1α/pVHL蛋白-蛋白相互作用抑制剂研究体系。

泛素-蛋白酶体系统在体内发挥着非常重要的生理功能，而具备E3泛素连接酶功能的蛋白主要负责对底物蛋白进行翻译后泛素化修饰，从而降解目标蛋白。不同于普通药物靶点，E3连接酶通常与底物蛋白发生蛋白-蛋白相互作用。本项目针对蛋白-蛋白相互作用抑制剂研究的关键问题：1）蛋白-蛋白相互作用抑制剂的发现和设计策略单一；2）现有HIF-1α/pVHL蛋白-蛋白相互作用抑制剂种类较少，开展了如下研究：针对蛋白-蛋白相互作用口袋大、作用力复杂、无法采用常规筛选小分子的手段等特点，我们选取了两个典型的蛋白-蛋白相互作用靶点-- MDM2/P53和HIF-1α/pVHL为研究对象，采用基于多晶体的药效团、级联对接、配体效率和分子动力学等技术，降低了筛选蛋白-蛋白相互作用抑制剂时的假阳性率；构建了蛋白-蛋白相互作用靶标特异性的天然产物库，解决了抑制剂来源质量问题；分别发现了9个全新MDM2/P53抑制剂和6个全新HIF-1α/pVHL抑制剂，并完成了体外活性评价；其次，在新骨架上，设计合成了衍生物26个，完成了HIF-1α/pVHL的抑制活性评价。本项目建立了经证实可供广泛推广的蛋白-蛋白相互作用抑制剂筛选的策略；共发现或合成各类化合物42个；负责人以第一作者发表SCI论文2篇；申请国家发明专利一项。本项目为后续研究奠定良好的基础。