靶向XBP1新结构激动剂筛选及抗溃疡性结肠炎作用机制研究

Ulcerative colitis (UC) is a chronic disease with refractory character, and occasionally convert to malignant intestinal disorder. At present, the effective clinical treatment is lacking for UC. X box binding protein 1 (XBP1) is the key nuclear transcription factor in the intestinal epithelial cells related with endoplasmic reticulum stress. Recently, evidences from clinical genetics and laboratory research were found that XBP1 down-expression or deletion can promote the occurrence and development of UC. Moreover, higher expression of XBP1 can be against the intestinal epithelial cell apoptosis induced by uncontrolled endoplasmic reticulum stress. However, there were no reports about XBP1 as a drug target in the research and development of UC therapeutic medicine. This project has established high-throughput drug screening model targeting XBP1 in vitro and acute or chronic UC experimental animal models in vivo, and started to screen series of new structure compounds which were presumed to have potential anti-inflammatory activity. The primary study showed that a class of compounds has significant XBP1 transcriptional activated effect, wherein ZZH-128 has higher anti-inflammatory activity dose-dependently in vitro and vivo. This study try to find more XBP1 agonists by screening, and to explore the detailed molecular mechanism of the compounds which have powerful activity, so as to laid the foundation of researching anti-UC drug targeting XBP1 molecularly.

溃疡性结肠炎(Ulcerative colitis，UC)是一种迁延发作、难于根治、易伴发恶变的肠道疾病，目前临床上缺乏有效的治疗药物及方法。X box binding protein 1 (XBP1)是肠上皮细胞内与内质网应激相关的关键性核转录因子。新近临床遗传学到实验室研究证据均表明：XBP1的表达下调或缺失会促进UC的发生及发展。但目前国内外有关UC药物研发中以XBP1作为靶标的药物尚无报道。本项目前期已建立靶向XBP1体外高通量药物筛选模型和体内急、慢性UC实验动物模型，并对推测具有抗肠道炎症的系列新结构化合物展开初筛。初步发现一类新结构化合物具有显著的XBP1转录激活效应，其中化合物ZZH-128体内活性较好，并呈现良好的量效关系。本研究拟进一步进行XBP1激动剂的筛选，并对体内外均具有较高活性的化合物进行详尽的分子作用机制研究，从而为创制分子靶向XBP1的抗UC药物研究奠定基础

溃疡性结肠炎(Ulcerative colitis，UC)是一种迁延发作、难于根治、易伴发恶变的炎性肠道疾病，目前临床缺乏有效治疗药物。因此寻找和发现特异性高、治疗效果佳和副作用少的抗UC新结构单体化合物，具有显著必要性。X box binding protein 1 (XBP1)是肠上皮细胞中重要的核转录因子。近五年从临床流行病学、遗传学到实验室研究结果均表明：XBP1表达的下调、异常或缺失会促进并加重UC发生及发展，且XBP1与肠上皮细胞和巨噬细胞中NF-κB的表达也密切相关。但目前国内、外有关UC药物研发中以XBP1作为靶标的研究尚无报道。. 本课题目前已顺利结题，基本阐明并解决以下几个问题：（1）首次在体外IEC-6肠上皮细胞中建立 “靶向激动XBP1双荧光素酶报告基因筛选模型”。该体系具有稳定性强、重复性好、特异性高、操作简便、成本适宜、周期较短等特点，可对定向及非定向合成的化合物展开高通量筛选；（2）从近百个定向合成的黄连碱类似物中，筛选到具有较好激动效应的单体化合物十余个。其中化合物2的EC50值为2.25nM，体内动物实验结果也显示出较好的抗UC活性，明显优于临床常用药SASP；（3）体内、外机制研究表明：①化合物2可以在不同层面激活xbp1基因转录及XBP1蛋白表达，具有一定的时效性和量效性；②在细胞及动物水平，化合物2可以有效抑制炎症状态下肠上皮细胞及肠组织中与UC发病密切相关细胞黏附分子、细胞因子的产生；③化合物2通过上调XBP1表达，进一步量效依赖性地抑制UC相关活性分子产生；④化合物2还可通过影响与肠上皮细胞经典及非经典NF-κB信号通路的某些关键节点，起到抗炎作用。其中活性化合物2通过调控“XBP1-NFκB”信号轴而在UC发病机制中的作用，为本研究首次发现并证明。. 本项目在国自然青年基金（项目号：81202546）资助下，通过建立并优化体外高通量抗UC筛选模型，对定向合成的单体化合物展开筛选；结合化合物2体内、外抗UC作用机制研究结果，初步明确了该活性化合物可能的作用新靶点（XBP1）及新信号通路（XBP1-NFκB），为下一步抗UC活性药物多靶点、多环节、多效应的治疗提供了可靠的、客观的试验基础和理论依据。目前已发表文章4篇，SCI收录3篇，单篇最高影响因子5.447，培养博士硕士研究生共2名。