Transporter Studies with the 3-O-Sulfate Conjugate of 17α-Ethinylestradiol: Assessment of Human Liver Drug Transporters
Transporter Studies with the 3-O-Sulfate Conjugate of 17α-Ethinylestradiol: Assessment of Human Liver Drug Transporters
复制标题
DOI：
10.1124/dmd.109.031518
复制
发表时间：
2010-07-01
影响因子：
3.9
通讯作者：
Rodrigues, A. David
中科院分区：
文献类型：
--
作者：
Han, Yong-Hae;Busler, Dennis;Rodrigues, A. David
17α-乙基雌二醇(EE2)是口服避孕药的一种成分，已知在肠道和肝脏中经历了相当大的首过3-O-硫化反应。一旦形成，3-O-硫酸盐结合物(EE2-Sul)在循环中被检测到可察觉的水平(与母体EE2相比)，并存在于胆汁中。因此，用冷冻保存的人原代肝细胞悬液来评估肝脏对EE2-Sul的摄取。在这种情况下，有证据表明存在活跃的(依赖于温度的)吸收，可用两个K-m(米氏常数)模型描述(K-m1=220海里米；K-m2=15.5微米)。四乙基铵或对氨基马尿酸盐不能抑制摄取(与90%类似)。EE2-Su1是重组有机阴离子转运肽(OATP1B1和OATP2B1)和Na+/牛磺胆酸共转运肽(NTCP)的底物，分别在人胚胎肾(HEK)293细胞中表达。OATP1B1的转运由两个K-m值(87 nM和141mM)描述，而OATP2B1和NTCP介导的HEK-293细胞摄取符合单一的K-m动力学(分别为10.7和2.6mM)。EE2Sul也被评估为外排转运体底物，使用表达胆盐输出泵、乳腺癌耐药蛋白(BCRP)和个别形式的多药耐药相关蛋白(MRP1、MRP2和MRP3)的膜小泡。运输研究也是用一种表达Pgp的细胞系进行的。只有含有BCRP的囊泡表现出对EE2-Su1的ATP依赖摄取(K-m1=2.9，K-m2=307µM)。总之，这些数据表明，肝脏对EE2-Sul的摄取可以通过三种转运体(OATP1B1、OATP2B1和NTCP)来介导，而胆汁中EE2-Sul的排泄可能涉及BCRP。
17 alpha-Ethinylestradiol (EE2), a component of oral contraceptives, is known to undergo considerable first-pass 3-O-sulfation in the intestine and liver. Once formed, the 3-O-sulfate conjugate (EE2-Sul) is detected in circulation at appreciable levels (versus parent EE2) and is present in bile. Therefore, hepatic uptake of EE2-Sul was assessed with suspensions of cryopreserved human primary hepatocytes. In this instance, there was evidence for active (temperature-dependent) uptake, which was described by a two-K-m (Michaelis constant) model (K-m1 = 220 nM; K-m2 = 15.5 mu M). Uptake was inhibited (similar to 90%) by bromosulfophthalein but not by tetraethylammonium or p-aminohippurate. In agreement, EE2-Sul was shown to be a substrate of recombinant organic anion transporter peptides (OATP1B1 and OATP2B1), and Na+/taurocholate-cotransporting polypeptide (NTCP), expressed individually in human embryonic kidney (HEK) 293 cells. Transport by OATP1B1 was described by two K-m values (87 nM and 141 mu M), whereas OATP2B1- and NTCP-mediated uptake into HEK-293 cells conformed to single K-m kinetics (10.7 and 2.6 mu M, respectively). EE2Sul was also assessed as an efflux transporter substrate using membrane vesicles expressing bile salt export pump, breast cancer resistance protein (BCRP), and individual forms of multidrug resistance-associated protein (MRP1, MRP2, and MRP3). Transport studies were also conducted with a cell line expression Pglycoprotein. Only vesicles that contained BCRP exhibited ATPdependent uptake of EE2-Sul (K-m1 = 2.9 and K-m2 = 307 mu M). Collectively, the data show that hepatic uptake of EE2-Sul can be mediated by three transporters (OATP1B1, OATP2B1, and NTCP), whereas biliary excretion of EE2-Sul into bile likely involves BCRP.