贵州天名精中抑制肿瘤干细胞活性倍半萜内酯类成分的发现

Sesquiterpene lactones (SLs), potential anti-tumor lead compounds, have significant pharmaceutical effects on inhibiting the activity of acute myeloid leukemia stem cell. Our previous work has confirmed that the SLs isolated from the extracts of Carpesium faberi have anti-acute myeloid leukemia stem cell effect. Meanwhile, the low-content sesquiterpene lactones dimmer compounds (SLDs) were also detected. On the basis of previous work, a combination approaches of HPLC-ESI-MSn and nonspecific alkaloid false positive method were developed to rapidly detect the SLs, and finally isolate the the target SL compounds. Thus, SLs, with the novel structures and significant activities on inhibiting acute myeloid leukemia HL-60 stem cell, were tentatively purified from Carpesium faberi. Structure characterization of the SLs was realized by spectroscopic and physicochemical methods. Stereochemistry configuration of SLDs was confirmed by single crystal X-ray diffraction method, ECD computation, theory of exciton chirality and NOESY related techniques. According to the research on activities and structure-activities analysis, one and/or two anti-tumor lead compounds were tentatively selected by the structure novelties, activities and selectivity, which may help laying a foundation for innovative and independent intellectual property rights of new anti-tumor drugs.

倍半萜内酯类成分具有显著抑制急性髓系白血病干细胞的活性，是潜在的抗肿瘤先导化合物。前期研究基础已经证实贵州天名精提取物中存在具有抗白血病干细胞作用的倍半萜内酯活性成分，同时还发现存在微量的二聚体倍半萜内酯活性成分。本项目运用HPLC-ESI-MSn技术和非特异性生物碱假阳性反应快速识别倍半萜内酯类成分，跟踪指导并最终实现目标化合物的分离，从贵州天名精植物中分离纯化结构新颖、具有显著抑制急性髓系白血病细胞株HL-60干细胞活性的倍半萜内酯类单体成分。通过波谱及理化方法对它们进行结构鉴定，并采用X-射线单晶衍射方法、ECD计算、激子手性理论及NOESY相关技术确定二聚体倍半萜内酯的立体构型。通过活性研究和构效关系分析，优选出1至2个结构新颖、活性强、选择性好的抗肿瘤先导化合物，为创新自主知识产权的新型抗肿瘤药物奠定基础。

本课题中采用多种现代色谱手段系统分离了三种天名精属植物，包括贵州天名精、烟管头草和大花金挖耳全草及地上部分的化学成分，从中得到162个单体化合物，应用光谱学方法(1H-NMR, 13C-NMR, DEPT , 1H-1HCOSY, NOESY, HMQC, HMBC, ESI-MS, IR)鉴定其化学结构，并培养出了部分二聚体倍半萜内酯类化学成分的单晶，通过Cu-Kα X-ray单晶衍射确定了化合物中各手性碳的绝对构型。对分离鉴定的化合物，通过MTT法和抗炎活性筛选，选出24个细胞毒活性成分，SAR分析表明其活性主要归因于结构中的α-亚甲基-γ-内酯功能基。同时发现8个具有抗白血病肿瘤细胞的活性成分，选择其中1个单体化合物进行急性髓系白血病干细胞活性筛选，发现有良好的抗AML干细胞活性，可作为抗白血病肿瘤先导化合物。