基于配体结合区的TRPM2 特异性抑制剂的设计、合成与生物活性研究

Transient receptor potential melastatin 2 channel (TRPM2) forms a non-selective cation channel that is activated by oxidative stress, which is mainly expressed in immune system and nervous system. Accumulative evidence has indicated TRPM2 play an important role in many pathological processes, such as inflammation and neurodegeneration diseases. To discover the effective specific TRPM2 inhibitors will bring great benefits to understanding the mechanism of TRPM2 mediated diseases and its drug therapy. In our previous work, by homology modeling, docking and virtual screening, we have found that two compounds inhibit TRPM2 activity by targeting to its ligand binding sites. In this project, these two structures will be used as lead compounds for chemical optimization, and biological activity evaluation with patch clamp and calcium imaging will be applied on the derivatives to get the information of structure-activity relationship and determine their specificity. The pharmacological functions of optimizing compounds will be evaluated both in vitro and in vivo. Then we will further determine whether the compounds can block the TRPM2 mediated neuronal death induced by global ischemia. Finally, the specific TRPM2 inhibitor discovered in this project will be not only used to investigate the gating mechanism of TRPM2 channel, but also a new potential clinical therapeutic drug for TRPM2 related diseases in future.

Transient receptor potential melastatin 2（TRPM2）是一种氧化应激损伤激活的非选择性阳离子通道，在免疫炎症发生及神经退行性疾病等病理过程中发挥重要作用，开发高效的TRPM2 特异性抑制剂对于揭示相关疾病机制和药物治疗具有重要意义。尽管目前已发现一些TRPM2抑制剂，但并不具有特异性。申请人前期通过同源模建、分子对接、虚拟筛选及活性评价，已发现两个作用于TRPM2配体结合区的小分子抑制剂。本项目拟以这两个活性分子为先导结构进行修饰，钙成像和电生理手段评价生物活性，优化构效关系，明确化合物作用的特异性；在离体和在体水平系统评价目标化合物的药理学功能，并明确其是否能抑制TRPM2介导的神经元死亡。本项目所发现的TRPM2 特异性抑制剂不仅能作为TRPM2通道门控机制研究的药理学工具，还将为今后治疗TRPM2介导的相关疾病提供潜在临床治疗药物。

TRPM2是一种氧化应激损伤激活的非选择性阳离子通道，在免疫炎症发生及神经退行性疾病等病理过程中发挥重要作用，开发高效的TRPM2 特异性抑制剂对于揭示相关疾病机制和药物治疗具有重要意义。本项目首先使用计算机辅助设计的方法利用已知结构的其他TRP家族蛋白对TRPM2通道的内源性配体结合区NUDT9-H进行了同源模建，进而通过分子对接及动力学模拟的方法解析了TRPM2内源性配体ADPR在该区域的结合位点，并使用点突变及电生理的方法对ADPR在这些位点的结合进行了验证；随后，以这些结合位点为基础，通过虚拟筛选获得了两类TRPM2抑制剂的先导结构，经初步化学官能团修饰及活性检测确定活性结构,并进行了一系列进一步的化学优化改造，进而总结出了该类化合物作为TRPM2抑制剂的构效关系；最后，以其中活性最强的化合物进行了抑制活性的特异性测试，同时在在体水平对该化合物对全脑缺血引发海马神经元死亡的保护作用进行了确认。综合以上，通过该项目的研究，我们初步获得了一个活性较强的TRPM2通道的特异性抑制剂，并证明了其对于全脑缺血引发的海马神经元死亡具有保护作用，未来该分子将不仅可以作为TRPM2通道门控机制研究的药理学工具，还将为今后治疗TRPM2介导的相关疾病提供潜在临床治疗药物。