DataSheet5_Cytotoxic and pro-apoptotic effects of botanical drugs derived from the indigenous cultivated medicinal plant Paris polyphylla var. yunnanensis.PDF

Background: Cancer is one of the top two leading causes of death worldwide. Ethnobotanical research, it is one of methods, which is able to discover effective anticancer drugs based on “prototype” of indigenous people’s historical experiences and practices. The rhizomes of Paris polyphylla var. yunnanensis (Franch.) Hand.-Mazz. have been used as botanical drugs to treat cancer by Yi, Bai, Dai, and Naxi ethnic groups in Yunnan, China, where this species is widely cultivated in a large scale in Yunnan.
Materials and methods: To identify the substances of anticancer activities based on indigenous medicine knowledge, chromatography was performed to separate saponins from the rhizomes of P. polyphylla var. yunnanensis, followed by spectroscopy to determine the structure of six isolated saponins. The cytotoxicity of five extracts and six pure compounds were evaluated by MTS method. Quantitative determination of total saponins of P. polyphylla var. yunnanensis was analyzed by HPLC. Cell cycle assay, apoptosis assay, and mitochondrial membrane potential were used to evaluate the pro-apoptotic activity in vitro.
Results: Five extracts and six pure saponins showed significant inhibitory cytotoxic activities of three human liver cancer cell lines (SMMC-7721, HepG2, and SK-HEP-1) and one non-small-cell lung cancer cell line (A549). The contents of Paris saponins I, II, and VII were 6.96% in the rhizomes of P. polyphylla var. yunnanensis, much higher than Chinese Pharmacopoeia standards (0.6%). Six saponins induced significant apoptosis and cell cycle arrest in three human cancer cell lines (A549, SMMC-7721, and HepG2), which was associated with the loss of mitochondrial membrane potential.
Conclusion: The result of this study support that cultivated P. polyphylla var. yunnanensis could be a substitute for wild resource as an anticancer medicine based on indigenous medicine knowledge.

研究背景：癌症是全球范围内位居前两位的致死病因之一。民族植物学研究是发掘有效抗癌药物的重要手段之一，可依托原住民的历史经验与实践“原型”，从中发现具有抗癌活性的药物成分。在中国云南的彝族、白族、傣族与纳西族族群中，滇重楼（Paris polyphylla var. yunnanensis (Franch.) Hand.-Mazz.）的根茎被作为植物药用于癌症治疗，且该物种在云南已得到广泛的规模化种植。
材料与方法：为基于民族医药知识鉴定具有抗癌活性的物质，本研究通过色谱法从滇重楼根茎中分离得到皂苷类成分，随后借助光谱法解析6种分离得到的皂苷的化学结构。采用MTS法评估5种提取物与6种纯化合物的细胞毒性。通过高效液相色谱法（High Performance Liquid Chromatography，HPLC）对滇重楼根茎中的总皂苷含量进行定量测定。此外，采用细胞周期实验、细胞凋亡实验以及线粒体膜电位检测，体外评价其促凋亡活性。
研究结果：5种提取物与6种纯皂苷对3种人肝癌细胞系（SMMC-7721、HepG2及SK-HEP-1）与1种非小细胞肺癌细胞系（A549）均表现出显著的细胞毒性抑制活性。滇重楼根茎中重楼皂苷I、II与VII的含量为6.96%，远高于《中国药典》规定的0.6%标准。6种皂苷可在A549、SMMC-7721及HepG2这3种人癌细胞系中诱导显著的细胞凋亡与细胞周期阻滞，该作用与线粒体膜电位丧失相关。
研究结论：本研究结果证实，基于民族医药知识，规模化种植的滇重楼可替代野生资源作为抗癌药物来源。