碱蓬多糖SSP1-1的分离纯化及其抗肿瘤活性

目的:本实验对水溶性碱蓬(Suaeda salsa)多糖SSP1-1进行分离纯化并对其抗肿瘤活性进行初步研究。方法:采用水提醇沉法提取碱蓬粗多糖,通过DEAE-52纤维素柱和Sephadex G-75葡聚糖凝胶柱分离纯化碱蓬粗多糖,得到单一碱蓬多糖SSP1-1,利用高效凝胶渗透色谱法(HPGPC)对其纯度及分子量进行分析,利用MTT、Hoechst 33342染色,Western blot方法对碱蓬多糖SSP1-1的抗肿瘤活性进行研究。结果:SSP1-1分子量为60.32 kDa;SSP1-1具有时间-剂量依赖性抑制肿瘤细胞增殖作用,当SSP1-1浓度为500 μg/mL时,HepG2细胞在24和48 h的细胞活力分别为52.8%和50.2%,Hoechst 33342染色实验观察到SSP1-1可引起HepG2细胞核出现典型的细胞凋亡特征;Western blot证明SSP1-1可以降低Bcl-2的蛋白表达,提高Bax和Caspase-3的蛋白表达,各组蛋白含量与对照组相比均具有显著性(P<0.05)。结论:SSP1-1为均一组分多糖,并对肿瘤细胞具有显著的抑制作用,为进一步开发利用碱蓬多糖奠定了基础。

Separation and Purification of Polysaccharide SSP1-1 from Suaeda salsa and Its Antitumor Activity

Objective:The purpose of this experiment was to purify the water-soluble polysaccharide SSP1-1 from Suaeda salsa and study its antitumor activity. Method:The crude polysaccharide from Suaeda salsa plant was extracted by water extraction and alcohol precipitation. The polysaccharide was further separated and purified by DEAE-52 cellulose column and Sephadex G-75 gel column. The molecular weight(M_W)and purity were analyzed by high performance gel permeation chromatography(HPGPC)and the antitumor activity of SSP1-1 was studied by MTT,hoechst 33342 and western blot. Result:The molecular weight of SSP1-1 was 60.32 kDa,SSP1-1 had a time-dose-dependent inhibition of tumor cell proliferation. When the concentration of SSP1-1 was 500 μg/mL,the cell viability of HepG2 cells was 52.8% and 50.2% at 24 and 48 h,respectively. It was observed that SSP1-1 could cause typical apoptosis characteristics of HepG2 nuclei in Hoechst 33342 staining test. Western blot proved that SSP1-1 could reduce the protein expression of Bcl-2,increase the protein expression of Bax and Caspase-3,and the protein content of each group was significant compared with the control group(P<0.05). Conclusion:SSP1-1 was a homogeneous polysaccharide and had a significant inhibitory effect on HepG2 cells,which laid a foundation for development and utilization of Suaeda salsa polysaccharide.