甘草次酸18位差向异构体对P-gp底物罗丹明123在Caco-2细胞上跨膜转运的影响  

Effect of Glycyrrhetinic Acid C-18 Epimerides on Membrane Transport of P-gp Substrate Rhodamine 123 in Caco-2 Cell Monolayers

作　　者：颜苗[1,2] 方平飞[1,2] 李焕德[1,2] 徐萍[1,2] 郑媚[3] 张金娇 

机构地区：[1]中南大学湘雅二医院药学部,长沙410011 [2]中南大学临床药学研究所,长沙410011 [3]广西医科大学第一附属人民医院,南宁530021 [4]广西梧州制药股份有限公司,广西梧州543002

出　　处：《中国药学杂志》2012年第19期1552-1558,共7页Chinese Pharmaceutical Journal

基　　金：国家自然科学基金资助项目(30873114);湖南省自然科学基金重点项目(11JJ2052);中央高校基本科研业务费专项基金资助项目(2012QNET151)

摘　　要：目的研究甘草次酸18位差向异构体即18α-甘草次酸(α-GA)、18β-甘草次酸(β-GA)对P-糖蛋白(P-gp)底物罗丹明123在Caco-2细胞上跨膜转运的影响。方法采用MTT法检测不同摩尔浓度的18α-甘草次酸、18β-甘草次酸及维拉帕米对Caco-2细胞生长抑制作用;建立Caco-2单层细胞模型,以P-糖蛋白底物罗丹明123(Rho-123)为荧光探针,评价甘草次酸18位差向异构体和P-糖蛋白抑制剂维拉帕米对罗丹明123在Caco-2细胞上跨膜转运的影响。罗丹明123浓度采用酶标仪检测。结果高浓度(10μmol.L-1)18α-甘草次酸瞬时作用于Caco-2细胞单层模型,或者干预单层模型72 h后,均使罗丹明123单位面积BL-AP侧累积转运量(transport B-A)增加,外排率(ER)增大,诱导P-糖蛋白底物罗丹明123外向转运;高浓度(10μmol.L-1)18β-甘草次酸瞬时作用于Caco-2细胞单层模型没有表现出诱导作用,但在干预Caco-2单层模型72 h后,表现出对罗丹明123外向转运的诱导;各实验药物均没有对罗丹明123 AP-BL侧转运产生影响。结论跨膜转运实验结果表明,18α-甘草次酸、18β-甘草次酸能诱导P-糖蛋白的外向转运,加速P-糖蛋白底物的外排,可能是甘草酸制剂增强肝脏解毒的机制之一。OBJECTIVE To study the effects of C-18 epimers of glycyrrhetinic acid, 18α-glycyrrhetinic acid （α-GA） and 18β- glycyrrhetinic acid（β-GA）, on membrane transport of P-gp substrate rhodamine 123 in Caco-2 cell monolayers. METHODS MTF assay was applied to determine the maximum non-cytotoxic dose of α-GA,β-GA and verapamil to ensure the activity of the cells during the test and to consult the maximum test concentration of each drug; appropriate Caco-2 monolayers were established in TranswellTM plates. ELISA Reader was applied to detect the concentration of Rho-123 in transfer fluid. The bi-directional transport of Rho-123 after being treated by instantaneous action and incubation with α-GA and β-GA for 72 h was studied. RESULTS High concentration （ 10μmol· L-1） of α-GA induced the efflux of Rho-123 both in the instantaneous action test and the incubation test. High concentration （ 10β-mol· L-1 ） ofβ-GA induced the efflux of Rho-123 only in the incubation test. The transport from AP to BL was not affected by any test drugs. CONCLUSION The results of the transport experiments of P-gp substrates in Caco-2 monolayers indicated that α-GA and α-GA can induce the efflux function of P-gp and accelerate the excretion of P-gp substrates. It may be one of the mechanisms of that glycyrrhizin preparation enhances liver detoxification.

关 键 词：18α-甘草次酸 18Β-甘草次酸 差向异构体 P-糖蛋白 罗丹明123 跨膜转运 

分 类 号：R965[医药卫生—药理学]