Reversal of P-glycoprotein expressed in Escherichia coli leaky mutant by ascorbic acid
Reversal of P-glycoprotein expressed in Escherichia coli leaky mutant by ascorbic acid
复制标题
DOI：
10.1016/s0024-3205(03)00376-x
复制
发表时间：
2003-07-11
期刊：
影响因子：
6.1
通讯作者：
Abou-Donia, MB
中科院分区：
文献类型：
--
作者：
El-Masry, EM;Abou-Donia, MB
据报道，多药耐药蛋白p -糖蛋白（P-gp）在大肠杆菌中的功能表达可用于筛选P-gp底物和抑制剂。本研究利用亚硝基胍和紫外诱变技术构建了28个大肠杆菌UT5600的泄漏突变体。这些突变体对已知P-gp底物和亲脂性癌症药物的毒性作用非常敏感。小鼠mdr1在最具渗透性的大肠杆菌突变体（UTP17）中功能性表达。该突变体中P-gp的表达使其对丝裂霉素C、替加富、柔红霉素、罗丹明6G、四苯基溴化磷和环丙沙星具有交叉抗性。为了研究P-gp在这个异源系统中表达的逆转，将表达小鼠mdr1或lac渗透酶的UTP17细胞作为阴性对照，用不同浓度的丝裂霉素C（含或不含抗坏血酸）处理。我们发现抗坏血酸消除了P-gp介导的多药耐药，提示抗坏血酸可能与抗癌药物联合使用以减少多药耐药的出现。我们还证明了番茄凝集素拮抗坏血酸的抑制作用。本研究提供了一种在大肠杆菌泄漏突变体中表达mdr1的异源系统，该系统可作为筛选P-gp诱导剂和抑制剂的系统，具有快速和简单的优点。(C) 2003爱思唯尔科学有限公司版权所有。
It has been reported that functional expression of the multidrug resistance protein P-glycoprotein (P-gp) in E. coli is useful for screening P-gp substrates and inhibitors. In the present study, we have constructed by nitrosoguanidine and UV mutagenesis 28 leaky mutants of E. coli UT5600. These mutants are significantly susceptible to the toxic effect of known P-gp substrates and lipophilic cancer drugs. Mouse mdr1 was functionally expressed in the most permeable E. coli mutant (UTP17). Expression of P-gp in this mutant confers cross-resistance to mitomycin C, tegafur, daunorubicin, rhodamine 6G, tetraphenylphosphonium bromide and ciprofloxacin. To examine the reversal of P-gp expressed in this heterologous system, UTP17 cells expressing mouse mdr1 or lac permease as negative control were treated with various concentrations of mitomycin C with or without ascorbic acid. We found that ascorbic acid abrogated P-gp mediated multidrug resistance, suggesting that ascorbic acid might be used in combination with anticancer drugs to reduce emergence of multidrug resistance. We also demonstrated that tomato lectin antagonized the inhibitory action of ascorbic acid. This study provide a heterologous system for mdr1 expression in E. coli leaky mutant that can be used as a system for the screening of P-gp inducers and inhibitors, since it is quick and simple. (C) 2003 Elsevier Science Inc. All rights reserved.