太白银莲花皂苷B对胶质瘤细胞生长抑制的研究

目的:太白银莲花皂苷B(Anemone taipaiensis saponin B)是第一次从太白银莲花中经过系统化学分析和分离鉴定的皂苷之一,所以它的生物学效应目前仍然不清楚。在本研究中,我们首次体外研究太白银莲花皂苷B对胶质瘤细胞系的生物学效应,观察它对胶质瘤细胞增殖的的抑制作用。方法:采用四甲基偶氮唑蓝(MTT)法测定太白银莲花皂苷B对胶质瘤细胞生长曲线的影响,Hoechst 33342细胞核染色后荧光显微镜观察,采用光学显微镜观察细胞的形态学变化。结果:MTT实验结果显示太白银莲花皂苷B对胶质瘤细胞U87MG和U251MG有强烈的生长抑制作用,且具有剂量依赖性,应用SPSS18.0统计软件得出太白银莲花皂苷B对U87MG细胞72 h的抑制浓度为IC25=5.2μmol/L,IC50=6.7μmol/L and IC75=8.7μmol/L,U251细胞的抑制浓度为IC25=6.2μmol/L,IC50=7.9μmol/L and IC75=10.5μmol/L。Hoechst 33342细胞核染色荧光显微镜观察以及光学显微镜下细胞形态观察显示出典型的凋亡细胞形态学特征,经过皂苷B处理后,细胞皱缩成圆球形,细胞核碎裂或者致密浓染,向核膜边缘聚集,染色质浓缩为半月状、车轮状或者马蹄状,凋亡小体出现。这些特征在24 h时更明显。结论:体外实验初步显示,太白银莲花皂苷B对U87MG和U251MG细胞具有明显的增殖抑制作用,并具有促凋亡作用。

Saponin B,a Cytostatic Compound Purified from Anemone Taipaiensis,Inhibit Proliferation Obviously in Human Glioblastoma Cell Line

Objective： Anemone taipaiensis saponin B was first isolated from Anemone taipaiensis, a ferine plant of the Qinling mountains of southern Shaanxi province, China, that is distributed in the hill country of the fertile slopes or rocky grasslands at altitudes between 2900 and 3700 m. in this paper, we first investigated the impact of saponin B to the human glioblastoma cell, as an in vitro model to explore the effects of saponin B on GBM cell growth and apoptosis. Methods： the 3- （4, 5-dimethyl）-2, 5 diphenyl tetrazolium bromide （MTT） assay was used to evaluate the cell proliferation, apoptosis was analyzed after staining of the ceils with Hoechst 33342 （Sigma Aldrich） and follow fluorescence microscopy. Results： The results of MTT showed that saponin B significantly suppressed U87MG and U251MG cell Proliferation. For U87MG cells, the inhibitory concentrations of saponin B at 72 h were found to be IC25 = 5.2μmol/L, IC50 = 6.7μmol/L and IC75= 8.7 μmol/L. For U251MG cells, the inhibitory concentrations were IC25 = 6.2 μmol/L, IC50 = 7.9μol/L and IC75= 10.5μmol/L（SPSS 18.0）. Chromatin condensation and the apoptotic bodies observed by fluorescence microscopy, We determined the residual cell viability and number of apoptotic cells in glioma U87MG cells after treatment with saponin B at the concentrations ofIC25, IC50 and IC75 for 8 and 24 h. Typical of the induction of apoptosis were observed： （a） weak and irregularly shaped marginal chromatin condensation; （b） highly condensed nuclear chromatin that was inverted in one side; （c） relatively compact and irregularly shaped marginal chromatin condensation, under light microscopy, with increasing concentrations of saponin B, cells were increasingly found in rounded form. Conclusion： As pointed out by the experimental results, saponin B is an efficient cytostatic agent of glioblastoma cells, may be considered a novel compound can inhibit glioma cell growth and survival.