三种抗白血病植物活性成分及其对MDR的逆转机制研究

项目名称： 三种抗白血病植物活性成分及其对MDR的逆转机制研究

项目编号： No.20872148

项目类型： 面上项目

立项/批准年度： 2009

项目学科： 化学工业

项目作者： 王易芬

作者单位： 中国科学院昆明植物研究所

项目金额： 31万元

中文摘要： 从天然产物中寻找和发现先导化合物或候选化合物是研究抗白血病药物的关键，也是目前国内外研究天然药物活性成分的热点。本项目是在已发现有较好抗白血病活性植物- - 云南升麻、酸叶胶藤、滇黄精和钱线莲的基础上，继续开展化学成分分离鉴定与活性筛选，对较好活性单体进行细胞凋亡机制研究。利用多种分离材料进行层析分离与制备，从中共获得了107个单体成分，并通过波谱、光谱鉴定其结构，类型涉及三萜皂苷、甾体皂苷、黄酮、生物碱及木质素等。其中有新化合物14个。同时体外筛选了大部份化合物对不同肿瘤细胞株的细胞毒性（包括白血病细胞株），最强活性的化合物为三萜皂甙。因此制备了活性三萜皂苷类化合物各5克以上供细胞凋亡机制研究。初步探讨了三萜皂苷通过线粒体途径诱导乳腺癌细胞凋亡的作用机制。D rhamnose βederin抗乳腺癌干细胞 （TBCs）及联合用药研究结果表明该化合物不仅具有抗乳腺癌的作用，还显示了针对TBCs的特异性杀伤作用。通过三年积极开展研究工作以来，共发表研究论文7篇，其中4篇SCI收录论文，培养硕士研究生五名（两名毕业，三名在读）。由于研究论文发表有一定时间差，还有部份研究论文有待发表。

中文关键词： 白血病；细胞凋亡；中草药；活性成分

英文摘要： The key research of the drug development against human leukaemia is that candidate compounds are found from natural products. This is a hot research for active constituents from natural products over the world. Previous study on the constituents of five medical plants (Cimicifuga yunnanensis, Ecdysanthera rosea, Polygonatum kingianum and Clematis ganpiniana)showed that several compounds indicated significant inhibitory activities against humnan leukaemia cells CCRF-CEM. Totally 107 compounds were isolated and identified by various chromatographies over silica gel column, Sephadex LH-20, MCI CHP-20P, RP-8 and RP-18 si gel. Those compounds covered triterpenoids, steroids, flavanones, flavones, alkaloids and lignans. Among them, 14 were new ones. On the other hand, the cytotoxicity of all most compounds were tested in vitro against several tumor cell lines (including leukemia cell line) by MTT. Triterpenoids and steroids showed significant cytotoxicity and induced apoptosis through the mitochondrial pathway. Active triterpenoids (each 5 g) were prepared for the mechanism research. Two methods (fixed-concentration and combination index) were used to assay simultaneous drug combinations of D rhamnose βederin and docorubicin in vitro. In both ways, D rhamnose βederin enhanced cytotoxicity of doxorubicin. But the results also suggested that synergistic effect only existed in moderate cytotoxic range of concentration that below IC 50. On the contrary, an antagonistic effect appeared at a high level of growth inhibiton. In addition, apoptosis was observed increasing significantly when the two agents were combined at the moderate concentrations. Considering plasma concetration of drugs in vivo is relatively low and in the synergistic concentration range. D rhamnose b-hederin could be a promising candidate for combined chemotherapy with doxorubicin to breast cancer. A total of seven papers were published, of which 4 indexed by SCI.Five masters graduated training (two graduate and three in the reading).

英文关键词： Human leukaemia; apoptosis; herb medicine;active constituent