五味子提取物对脑胶质瘤神经球细胞增殖的抑制作用

Inhibitory effect of Schisandra chinensis extract on proliferation of neurospheres of glioma

目的:探讨五味子提取物对脑胶质瘤神经球细胞生长的作用,并初步探讨其可能的机制。方法:培养脑胶质瘤SHG-44细胞,将其置入干细胞培养液[神经培养基加入B27添加物、表皮生长因子(EGF)和碱性成纤维细胞生长因子(bFGF)]中进行培养,3代以后用于实验。将脑胶质瘤SHG-44细胞分为对照组,50、100和200mg·L-1五味子提取物组,MTT法检测各组神经球细胞的增殖抑制率,酶联免疫吸附实验检测五味子提取物作用后神经球培养上清中Bcl-2、Bax和caspase-3蛋白表达水平。结果:MTT法检测,与对照组比较,50、100和200mg·L-1五味子提取物组SHG-44神经球细胞24、48和72h时增殖抑制率均升高(P<0.01);酶联免疫吸附实验,不同浓度五味子提取物作用神经球48h后,培养上清中Bcl-2和Bax蛋白表达水平均下降,以Bcl-2蛋白表达水平下降更为明显,与对照组比较,100和200mg·L-1五味子提取物组Bcl-2蛋白表达水平明显下降(P<0.05或P<0.01);与对照组比较,不同浓度五味子提取物组Bax/Bcl-2值均升高(P<0.05或P<0.01),50mg·L-1五味子提取物组培养上清中caspase-3蛋白水平较对照组明显升高(P<0.01)。结论:五味子提取物可能是通过上调Bax/Bcl-2值后促凋亡因素占优势,使神经球细胞凋亡而抑制胶质瘤神经球细胞的生长。

Objective To explore the effect of Schisandra chinensis extract on neurospheres of glioma and to study the possible mechanism of inhibition.Methods Glioma SHG-44cells were cultured in stem cells media（containing neurobasal media supplemented with B27,EGF and bFGF）and the neuroshperes were used in this experiment after 3passages.Neurospheres were cultured and divided into control,50,100and 200mg·L-1 Schisandra chinensis extract groups.The influence of Schisandra chinensis extract in proliferation of neuroshperes was measured by MTT assay.The levels of Bcl-2,Bax and caspase-3proteins were measured by ELISA.Results Compared with control group,the inhibitory rates of proliferation of neurospheres in 50,100and 200 mg·L-1 Schisandra chinensis extract groups were significantly decreased after treated for 24,48and 72h（P0.01）.The ELISA results showed that compared with control group,the secretion of Bcl-2 and Bax protein was decreased,especially the levels of Bcl-2protein in 100and 200mg·L-1 Schisandra chinensis extract groups（P0.05or P0.01）;compared with control group,the ratios of Bax/Bcl-2in 50,100and 200mg·L-1 Schisandra chinensis extract groups were increased（P0.01）.Compared with respective control group,the expression of caspase-3protein in 50mg·L-1 group was significantly increased（P0.01）.Conclusion Schisandra chinensis extracts might upregulate the ratio of Bax/Bcl-2and promote the secretion of apoptosis factors to induce the apoptosis and inhibit the growth of glioma neuroshperes.