Experiment Of Angelica Angelica Polysaccharide On Apoptosis Of Leukemic Cell Line K562

Objective:Angelica polysaccharide is a natural product extracted and purified from Gansu Province by Zhongnan Hospital of our uiversity ,which exerts significant antitumor activity in vitro,the barget is the microtubules in cells.Our research was carried out to investigate the effect of angelica polysaccharide on K562 leukemia cell lines,and explored its mechanism of apoptosis in vitro.Methods: (1) Inhibition of proliferation was observed on K.562 cell lines by angelica polysaccharide.After K562 cell treated with angelica polysaccharide at 250-1000ug/ml,effects to cell proliferation were evaluated firstly with trypan blue exclusive assay. (2) Apoptotic phenomena were explored as the mechanism of angelica polysaccharide.The morphologic of apoptosis cells were determined by inverted microscope and electronic microscope.(3) To gain more information cellular DNA was extracted ,dialyzed and electrophoresed in agarose gel.(4) Quantitative detection of apoptotic cells and analysis of cell cycle distribution were determined by flow cytometry.Results: (1)The cell lines were significantly inhibited by angelica polysaccharide in dose-dependent and time-dependent manners.(2) After cells exposed to angelica polysaccharide for 3 days , four types of cell morphology were visualized,including the live and dead cell with normal chromatin, the early and later apoptotic cells with condensed and fragmentized chromatin.Furthermore,the apoptotic phenomena characterized by cell volume reduction,cytoplasm shrinkage,condensation and fragmentation of chromatin, apoptotic bodies were observed with electronic microscopy.(3) Neuclear DNA fragmentation did not exhibit the typical "ladder" pattern.(4) According to the results, the sub-G1 peak represented the presence of apoptotic cells, and the apoptotic rate to K562 cells by 1000ug/ml was 3.9%( 3d).It was also demonstrated that the cell cycle of the cell lines was arrested in S phase.Conclusions: (1) It shows potent inhibitory activity on the growth and proliferation K562 cell. (2) The antitumor activity may mainly contribute the cell apoptosis induced by angelica polysaccharide.