靶向谷氨酸脱氢酶NADP+结合口袋的小分子抑制剂及其作用机制研究

异常活跃的谷氨酰胺代谢为肿瘤细胞的快速增殖提供能量和物质补偿，谷氨酸脱氢酶(GDH1)是该通路下游的关键酶，在许多恶性肿瘤中异常高表达。现有的GDH1抑制剂局限于高通量筛选得到的多酚类化合物，针对GDH1的合理药物设计尚未见文献报道。我们的前期研究发现辅酶NADP+与GDH1具有高亲和力(Kd=77nM)，比底物和其他辅酶的亲和力高1000倍以上，因此我们推断“NADP+竞争性抑制剂可能阻断NADP+与GDH1的结合，从而增加化合物对GDH1的抑制作用和抗肿瘤活性”。据此本项目拟以非酚类化合物依布硒啉为先导，基于GDH1的晶体结构设计并合成一系列靶向GDH1-NADP+结合口袋的竞争性抑制剂。通过多重活性评价得到1-2个活性先导化合物，并重点研究其与GDH1的结合模式和细胞水平的靶向性。本项目的研究将为GDH1抑制剂的合理设计奠定良好的实验基础，为GDH1抑制剂的深入研究和应用提供理论依据

Highly active glutaminolysis provides tumor cells with energy and material compensation to fuel their rapid proliferation. Glutamate dehydrogenase (GDH1) is a key enzyme in downstream of glutaminolysis, which is abnormally high expressed in many malignant tumors. The known GDH1 inhibitors are limited to polyphenols obtained by high-throughput screening, while rationally designed GDH1 inhibitors has not been reported. Our recent work showed that NADP+ had high affinity (Kd of 77 nM) for GDH1, which is 1000-fold higher affinity than its substrate and other coenzymes. Therefore, we concluded that NADP+ competitive inhibitors may block the binding of NADP+ to GDH1, thereby increasing the inhibitory effect and anti-tumor activity of GDH1 inhibitors. Given all this, this project intends to design and synthesize a series of competitive inhibitors targeting GDH1 at the NADP+ binding site based on its crystal structure with the non-phenolic compound ebselen as lead compound. After that, we will select 1-2 active lead compounds through multiple activity evaluation, and then focus on the study of their binding mode and cell-level targeting. So this project will lay a good experimental foundation for the reasonable design of GDH1 inhibitors, and provide a theoretical basis for the in-depth research and application of GDH1 inhibitors.