Zhang Jing, Liu Chao, Huang Ri-Zhen, Chen Hui-Feng, Liao Zhi-Xin, Sun Jin-Yue, Xia Xue-Kui, Wang Feng-Xiang
Department of Pharmaceutical Engineering, School of Chemistry and Chemical Engineering, Southeast University, Nanjing, P. R. China.
Institute of Agro-Food Science and Technology/Key Laboratory of Agro-Products Processing Technology of Shandong Province, Shandong Academy of Agricultural Sciences, Jinan, P. R. China.
PLoS One. 2017 Apr 7;12(4):e0175502. doi: 10.1371/journal.pone.0175502. eCollection 2017.
Three new lupane-triterpenoids (1-3) along with six known compounds (4-9) were isolated from the ethanolic extract of whole plant of Potentilla discolor Bunge. The structures of Compounds 1-3 were established by extensive 1D and 2D NMR together with other spectrum analysis, indicating that their C-27 positions were highly oxygenated, which were rarely found in nature. Their in vitro anti-proliferative activities against HepG-2, MCF-7 and T-84 cell lines were evaluated by Cell Counting Kit-8 (CCK-8) assay, and the results showed different activities for three cell lines with IC50 values ranging from 17.84 to 40.64 μM. In addition, the results from Hoechst 33258 and AO/EB staining as well as annexinV-FITC assays exhibited Compound 1 caused a markedly increased HepG-2 cellular apoptosis in a dose-dependent manner. The further mechanisms of Compound 1-induced cellular apoptosis were confirmed that 1 induced the production of ROS and the alteration of pro- and anti-apoptotic proteins, which led to the dysfunction of mitochondria and activation of caspase-9 and caspase-3 and finally caused cellular apoptosis. These results would be useful in search for new potential antitumor agents and for developing semisynthetic lupane-triterpenoid derivatives with high antitumor activity.
从翻白草全株乙醇提取物中分离得到3个新的羽扇豆烷型三萜（1-3）和6个已知化合物（4-9）。通过广泛的一维和二维核磁共振以及其他光谱分析确定了化合物1-3的结构，表明它们的C-27位具有高度氧化，这在自然界中很少见。采用细胞计数试剂盒-8（CCK-8）法评估了它们对HepG-2、MCF-7和T-84细胞系的体外抗增殖活性，结果显示对三种细胞系具有不同活性，IC50值在17.84至40.64μM之间。此外，Hoechst 33258和AO/EB染色以及膜联蛋白V-FITC检测结果表明，化合物1以剂量依赖性方式显著增加HepG-2细胞凋亡。化合物1诱导细胞凋亡的进一步机制得到证实，即1诱导活性氧生成以及促凋亡和抗凋亡蛋白的改变，导致线粒体功能障碍以及半胱天冬酶-9和半胱天冬酶-3激活，最终导致细胞凋亡。这些结果将有助于寻找新的潜在抗肿瘤药物以及开发具有高抗肿瘤活性的半合成羽扇豆烷型三萜衍生物。
