三氧化二砷、人参皂甙和 β榄香烯对K5 62细胞株端粒-端粒酶系统作用机制的研究

Effects of Arsenic Trioxide,Ginseng Saponin and β-Elemene on Telomere-Telomerase System in K562 Cell Line

本研究目的是探索三氧化二砷、人参皂甙及 β榄香烯等几种药物在不同浓度作用时对K5 6 2细胞株端粒长度和端粒酶活性的调节及抑制作用 ,并研究上述药物抗白血病的作用机制 ,为寻求治疗急性白血病的新方法奠定基础。用 3组不同浓度的三氧化二砷、人参皂甙及 β榄香烯与人类红白血病细胞株K5 6 2共培养 ,采用PCR ELISA法检测端粒酶活性 ,Southernblot法检测端粒长度。观察上述药物对K5 6 2细胞端粒酶活性及端粒长度的影响。结果表明 :①经人参皂甙、三氧化二砷及 β榄香烯作用后 ,K5 6 2细胞株端粒酶活性下降 ,下降程度呈浓度、时间依赖性 ,在一定浓度及作用时间后端粒酶呈阴性。②三氧化二砷、人参皂甙、β 榄香烯作用后K5 6 2细胞的存活率下降 ,且抑制作用呈浓度、时间依赖性。③三氧化二砷、人参皂甙及 β 榄香烯作用于K5 6 2细胞 72小时后 ,端粒长度略有延长。结论 :①三氧化二砷、人参皂甙及 β 榄香烯均能抑制K5 6 2细胞的端粒酶活性 ,抑制作用呈浓度、时间依赖性。抑制端粒酶活性可能是其抗肿瘤作用的机制之一。②三氧化二砷、人参皂甙及 β 榄香烯均能抑制K5 6 2细胞的生长 ,抑制作用呈浓度、时间依赖性。③抑制端粒酶活性后 ,K5 6 2细胞的端粒长度略有延长。本研究结果提示除了端粒酶以外 ,白血?

The aim was to explore the modulating and inhibiting effects of arsenic trioxide,ginseng saponin and β-elemene on telomere length and telomerase activity in K562 cell line,and to study their anti-tumor mechanism and seek new method of therapy for acute leukemia. Human erythroleukemia cell line K562 was co-cultured with arsenic trioxide,ginseng saponin,β-elemene separately,cells were collected after 24, 48 and 72 hours for further detecting. Telomere length and telomerase activity were detected by the methods of Southern-blot and PCR-ELISA respectively. The effects of these drugs on telomere length and telomerase activity were observed at different concentrations and length of time. The results showed that (1) telomerase activity of K562 cells decreased after co-cultured with arsenic trioxide,ginseng saponin and β-elemene. The inhibiting effects depended on drug concentrations and length of time. When co-cultured at proper concentration and period of time,telomerase activity could be inhibited;(2) viability of K562 cells decreased after co-cultured with arsenic trioxide,ginseng saponin and β-elemene,the inhibiting effect depends on drug concentrations and length of time;(3) after co-cultured with arsenic trioxide,ginseng saponin,and β-elemene for 72 hours,telomere length of K562 cell line prolonged a little. It is concluded that (1) arsenic trioxide,ginseng saponin and β-elemene can inhibit telomerase activity in K562 cell line,the supression of telomerase activity may be one of the mechanisms of anti-tumor effect;(2) arsenic trioxide,ginseng saponin and β-elemene can inhibit the growth of K562 cell line,the inhibiting effect depends on concentration and time;(3) when telomerase activity was supressed,the telomere length prolonged a little,indicating that in K562 cell line may exist another mechanism to regulate telomere length,except telomerase activation.