螺旋藻提取物对DNA拓扑异构酶活性的抑制及对DNA的直接影响  

Inhibition of DNA topoisomerases and direct DNA breakage by extract of spirulina plantensis geitl

作　　者：蒙凌华[1] 蒋超 刘兆乾[2] 齐清 丁健[1] 

机构地区：[1]中国科学院上海药物研究所,上海200031 [2]北京大学生命科学学院,上海200031 [3]北京柯瑞生物技术有限公司,北京100871

出　　处：《癌症》2000年第8期768-771,共4页Chinese Journal of Cancer

摘　　要：探讨螺旋藻提取物对DNA拓扑异构酶活性的影响以及对DNA的直接作用。方法 :TOPOI介导的负超螺旋 pBR322解旋反应检测对TOPOI酶活力的影响 ;TOPOII介导的kDNA去连环作用检测对TOPOII活力的影响 ;采用负超螺旋pBR322和kDNA检测对DNA的直接作用。结果 :螺旋藻提取物的水溶性成分和DMSO可溶性成分在浓度分别为3 2μg/ml和80μg/ml时,能完全抑制TOPOI介导的负超螺旋 pBR322解旋反应;两者对TOPOII介导的kDNA去连环作用完全抑制的浓度分别为16μg/ml和2000μg/ml。此外 ,螺旋藻提取物水溶性成分在高浓度时可直接引起DNA的双链断裂。结论 :TOPO酶 ,主要是TOPOI 。Objectives: To explore the effects of zaofukang on enzymatic activities of DNA topoisomerases (TOPO)and its direct effect on DNA Methods: The activity of TOPO I was measured by TOPO I mediated supercoiled pBR322 relaxation The activity of TOPO II was evaluated by TOPO II mediated kDNA decatenation Direct DNA breakages were determined by supercoiled pBR322 and kDNA Results: The TOPO I mediated DNA relaxations were completely inhibited by the water soluble component and the DMSO soluble component of zaofukang at the concentrations of 3 2 μg/ml and 80 μg/ml respectively The two components completely inhibited TOPO II mediated kDNA decatenation at the concentrations of 16 μg/ml and 2000 μg/ml respectively Furthermore, the water soluble component induced DNA breakage directly at a high concentration of 10 mg/ml Conclusion: These results suggest that topoisomerases, mainly TOPO I, would be one of thecellular targets of zaofukang

关 键 词：螺旋藻提取物 DNA拓扑异构酶 DNA断裂 

分 类 号：R730.53[医药卫生—肿瘤] R979.1[医药卫生—临床医学]