Adv Exp Med Biol. 2020;1292:157-169. doi: 10.1007/5584_2020_525.
Medicinal plants have been used for disease treatment throughout history, especially in Asia. Vietnam is a tropical country which possesses forests with a diversity of plants; among the plants, many have been historically used as alternative therapies for various disease treatments. In this study we aimed to evaluate the selective cytotoxicity of some plant extracts (collected from Vietnamese forests) against hepatocellular carcinoma cells HepG2, compared to adipose tissue-derived mesenchymal stem cells (ADSCs).
In this study, we collected nine plants and produced nine extracts from them; these included whole stem of Buchanania lucida, whole stem of Dipterocarpus turbinatus, Hopea recopei, whole stem of Shorea thorelii, bark of Shorea thorelii stem, bark of Dipterocarpus turbinatus stem, whole stem of Dipterocarpus costatus, bark of Dipterocarpus costatus stem, and rhizome of Boesenbergia pandurata. The cytotoxicity of these extracts on hepatocellular carcinoma cells and mesenchymal stem cells were determined based on IC values calculated using Alamar Blue assay. Based on these IC values, the side effect index (SEI) of extracts was determined. Only the extracts with low SEI were used in further assays to determine the apoptotic status of both hepatocellular carcinoma cells and mesenchymal stem cells via caspase 3/7 induction assay, nuclei disintegration (using Hoechst 33342 staining), and Annexin V staining assay.
The results showed that B. pandurata extract had strong cytotoxicity toward HepG2 cells with lowest side index on mesenchymal stem cells (IC on HepG2 of 222 ± 27.82 (μg/ml) but IC on ADSCs of 382 ± 16.19 (μg/ml)). Nuclear staining showed that B. pandurata extract could induce disintegration of cell nuclei at the concentration of 400 μg/ml. After 3 h of incubation with B. pandurata extract at the concentration of 200 μg/ml, the BP extract induced caspase 3/7 activation in HepG2 cells, but not in mesenchymal stem cells. Annexin V staining showed that the BP extract induced apoptosis in HepG2 cells in a dose-dependent manner.
This study revealed that selective cytotoxicity of some extracts on cancer cells could be determined based on their IC values on cancer cells and on mesenchymal stem cells. B. pandurata extract displayed the lowest side effect index on mesenchymal stem cells and successfully induced apoptosis in hepatocellular carcinoma cells HepG2 via activation of caspase 3/7.
药用植物在历史上一直被用于治疗疾病，尤其是在亚洲。越南是一个拥有多样化植物的热带国家，其中许多植物曾被历史上用于治疗各种疾病。在这项研究中，我们旨在评估一些植物提取物（从越南森林中采集）对肝癌细胞 HepG2 的选择性细胞毒性，与脂肪组织来源的间充质干细胞（ADSCs）进行比较。
在这项研究中，我们收集了 9 种植物，并从它们中制备了 9 种提取物；这些提取物包括 Buchanania lucida 的整株茎、Dipterocarpus turbinatus 的整株茎、Hopea recopei、Shorea thorelii 的整株茎、Shorea thorelii 茎的树皮、Dipterocarpus turbinatus 茎的树皮、Dipterocarpus costatus 的整株茎、Dipterocarpus costatus 茎的树皮和 Boesenbergia pandurata 的根茎。通过使用 Alamar Blue 测定法计算 IC 值，确定这些提取物对肝癌细胞和间充质干细胞的细胞毒性。根据这些 IC 值，确定提取物的副作用指数（SEI）。只有 SEI 较低的提取物被用于进一步的测定，以通过 caspase 3/7 诱导测定、核崩解（使用 Hoechst 33342 染色）和 Annexin V 染色测定来确定两种肝癌细胞和间充质干细胞的凋亡状态。
结果表明，B. pandurata 提取物对 HepG2 细胞具有很强的细胞毒性，对间充质干细胞的副作用指数最低（对 HepG2 的 IC 为 222±27.82（μg/ml），而对 ADSCs 的 IC 为 382±16.19（μg/ml））。核染色显示，B. pandurata 提取物可在 400μg/ml 的浓度下诱导细胞核崩解。在浓度为 200μg/ml 的 B. pandurata 提取物孵育 3 小时后，BP 提取物可在 HepG2 细胞中诱导 caspase 3/7 活化，但不在间充质干细胞中诱导。Annexin V 染色显示，BP 提取物以剂量依赖的方式诱导 HepG2 细胞凋亡。
本研究表明，可以根据提取物对癌细胞和间充质干细胞的 IC 值来确定某些提取物对癌细胞的选择性细胞毒性。B. pandurata 提取物对间充质干细胞的副作用指数最低，并通过激活 caspase 3/7 成功诱导肝癌细胞 HepG2 凋亡。
