藏药抗肝癌活性研究

In vitro anticancer screening of Tibetan medicines

本实验采用快速溶剂萃取法制备收集100种常用藏药的环己烷、乙酸乙酯和甲醇提取物,并运用MTT法对两个肝癌细胞株HepG2和SMMC-7721进行各提取物的抗肝癌活性测试,同时选用L-02细胞来评价其体外毒性.抗肝癌活性结果显示100种常用藏药中17种藏药材有良好的抗肝癌活性,其IC_(50)值均小于150μg/mL,其中马兜铃、蓝翠雀花、甘青青兰、掌叶橐吾的乙酸乙酯提取物显示出显著的抗肝癌活性,其IC_(50)值均小于50μg/mL,但马兜铃乙酸乙酯提取物对正常肝细胞L-02显示出一定的毒性.在进一步的抗HepG2肝癌活性验证中,结果显示蓝翠雀花乙酸乙酯提取物和甘青青兰乙酸乙酯提取物具有显著的抗肝癌活性,两者在抗HepG2肝癌细胞株活性中皆显示出显著的时效和量效关系.运用倒置显微镜以及Hoechst 33258荧光染色法对经过蓝翠雀花乙酸乙酯提取物或甘青青兰乙酸乙酯提取物作用的HepG2细胞形态进行观察,结果提示蓝翠雀花和甘青青兰乙酸乙酯提取物可能是通过诱导HepG2细胞凋亡而显示抗癌活性.

The extraction of cyclohexane, ethyl acetate and methanol from 100 commonly used Tibetan medicines was prepared by the accelerated solvent extraction method. The MTT method was used to test antitumor activity of these 100 tibetan medicines against two hepatocellular carcinoma cell lines HepG2 and SMMC-7721, while preliminary toxicity towards normal human cells was investigated using a human liver cell line L-02. The antitumor screening results showed that 17 tibetan medicines exhibited antitumor activities against HepG2 and SMMC-7721 with IC50 values less than 150 μg/mL. Among them, the ethyl acetate extracts of Aristolochia impresinervis, Delphinium caeruleum , Dracocephalum tanguticum and Ligularia przewalskii showed significant antitumor activity against HepG2 and SMMC-7721 with IC50 values less than 50 μg/mL, but tthat of Aristolochia impresinervis showed certain toxicity against L-02 up to 200 μg/mL. In the further validation of anti-HepG2 liver cancer activity, the results signi- fied that the ethyl acetate extracts of Delphinium caeruleum and Dracocephalum tanguticum had significant anti-hepatocarcinoma activities, both of which presented significant time and dose dependent relationships against HepG2 hepatocarcinoma cell lines. The morphological changes of HepG2 cells treated with the ethyl acetate extracts of Del phinium caeruleum or Dracocephalum tanguticum were investigated by inverted microscope and Hoechst 33258 fluorescent staining method. The results demonstrated that apoptosis were induced by the ethyl acetate extracts of Delphinium caeruleum and Dracocephalum tanguticum anti-cancer in HepG2 cells.