双依他尼酸乙醇胺对谷胱甘肽S-转硫酶mu的选择性抑制作用  

Characterization of Aminoethanol Di-ethacrynic Acid as a Selective Divalent Potent Inhibitor of Glutathione S-transferase mu

作　　者：同婷婷 段昌园 李欣蓬 廖飞 杨晓兰[1] Tong Tingting;Duan Changyuan;Li Xinpeng;Liao Fei;Yang Xiaolan(Key Laboratory of Medical Laboratory Diagnostics of the Ministry of Education of China,College of Laboratory Medicine,Chongqing Medical University,Chongqing,400016;School of Pharmacy and Bioengineering,Chongqing University of Technology,Chongqing,400054)

机构地区：[1]重庆医科大学检验医学院,临床检验诊断学教育部重点实验室,重庆400016 [2]重庆理工大学药学与生物工程学院,重庆400054

出　　处：《基因组学与应用生物学》2021年第1期406-413,共8页Genomics and Applied Biology

基　　金：国家自然科学基金项目(31570862,81773625)资助。

摘　　要：谷胱甘肽S-转移酶(GST)的同工酶mu (GSTM)高表达与卵巢癌顺铂耐药有关。以GST非选择性抑制剂依他尼酸设计二价潜抑制剂双依他尼酸乙醇胺(aminoethanol di-ethacrynic acid, ADEA),测定ADEA及其与还原型谷胱甘肽(glutathione, GSH)加合物对GST同工酶亚型A1、P1、M2的半抑制浓度(IC50)、抑制类型、结合比和结合动力学。ADEA本身对GSTM2的IC50比GSTA1低300倍,比GSTP1低3 000倍;ADEA与GSH在酶催化下反应10 min所得产物,对上述3种同工酶的IC50分别降低5、57、200倍。ADEA本身和产物对GSTM2相对于底物CDNB是反竞争性抑制剂,ADEA本身对GSTM2相对于底物GSH是混合性抑制剂,ADEA与GSH产物对GSTM2相对于底物GSH是反竞争性抑制剂。分析ADEA对GSTM2荧光静态淬灭表明ADEA及其产物是二价结合;分析荧光和酶活性随时间变化表明酶与ADEA本身结合速度比其产物CDNB慢10倍。ADEA是有效的GSTM2选择性二价潜抑制剂。The over-expression of glutathione s-transferase mu(GSTM) is associated with drug resistance in ovarian cancer. To design potent inhibitors specific for GSTM2, a bivalent pro-inhibitor referred to aminoethanol di-ethacrynic acid(ADEA) was prepared and characterized. Against recombinant isozymes GSTA1, GSTP1 and GSTM2, the half inhibition concentrations(IC50), inhibitory types, binding ratios and binding kinetics of ADEA and its GSH conjugate were compared. The IC50 of ADEA on GSTM2 was 300-fold lower than that on GSTA1 and 3000-fold lower than that on GSTP1. After pre-incubation with GSH in excess and a GST isozyme for 10 min, IC50 values of the GSH conjugate on GSTM2, GSTA1 and GSTP1 decreased by 5, 57 and 200 times, respectively.ADEA itself and the GSH conjugate were uncompetitive inhibitors of GSTM2 against CDNB, ADEA itself was a mixed inhibitor of GSTM2 relative to GSH, and its GSH conjugate was an uncompetitive inhibitor of GSTM2 relative to GSH. According to the static quenching of protein fluorescence of GSTM2, ADEA and its product were bound to GSTM2 in the bivalence state. The fluorometric titration and enzyme initial activity gave the binding rates of ADEA to GSTM2 ten-fold lower than those of the product. ADEA is thus a potent divalent pro-inhibitor to GSTM2.

关 键 词：双依他尼酸乙醇胺 谷胱甘肽转S-转硫酶mu 二价潜抑制剂 依他尼酸 

分 类 号：R96[医药卫生—药理学]