Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark.
Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark.
Int J Pharm. 2019 Jun 30;565:306-315. doi: 10.1016/j.ijpharm.2019.05.023. Epub 2019 May 11.
The aim of the present study was to investigate the ability of non-ionic surfactants to inhibit MRP2-mediated transport in vitro in MDCKII MRP2 cells. Transport studies across MDCKII MRP2 cell monolayers were performed using H-etoposide and H-digoxin. 19 different non-ionic surfactants, including several polysorbates (PS), cremophor EL, vitamin E-TPGS, and n-nonyl β-D-glucopyranoside (NG), were investigated. Barrier function of the cells was investigated measuring TEER and transport of C-glycine. The amount of isotope was quantified using liquid scintillation counting. In MDCKII MRP2 cells a polarized transport of etoposide and digoxin in the secretory (basolateral to apical) direction with efflux ratios of 5.5 ± 0.7 and 18.5 ± 4.2, respectively, was measured. P-gp inhibitors such as valspodar and zosuquidar did not affect etoposide transport, and furthermore PS20 decreased secretory transport of digoxin, but not of etoposide. Transport of etoposide was therefore mainly MRP2-mediated and used as a probe to investigate pharmaceutical excipients. Non-ionic surfactants did not modulate etoposide transport across intact cell monolayers of MRP2 overexpressing MDCKII cells, although preliminary studies suggest that most were able to alter MRP2-mediated efflux of the fluorescent 5-chloromethylfluorescein (CMF). In conclusion, etoposide transport across MDCKII MRP2 cells was modulated by cyclosporin A, an inhibitor of MRP2 and P-gp, but not by specific P-gp inhibitors (valspodar and zosuquidar), which suggests that etoposide transport is primarily influenced by MRP2. In addition, commonly used non-ionic surfactants did not decrease MRP2-mediated etoposide transport in MDCKII MRP2 cells. These results suggest that etoposide transport in MDCKII MRP2 cells is a model system to investigate MRP2 interactions, and that surfactants may not have a large potential for increasing oral bioavailability of drugs through inhibition of MRP2 transport activity.
本研究旨在探讨非离子型表面活性剂在体外对 MRP2 介导的转运的抑制能力。采用 H-依托泊苷和 H-地高辛在 MDCKII MRP2 细胞单层上进行转运研究。研究了 19 种不同的非离子型表面活性剂，包括几种聚山梨酯（PS）、吐温 80、维生素 E-TPGS 和正壬基-β-D-吡喃葡萄糖苷（NG）。通过测量跨上皮电阻（TEER）和 C-甘氨酸的转运来研究细胞的屏障功能。使用液体闪烁计数定量同位素的量。在 MDCKII MRP2 细胞中，测量到依托泊苷和地高辛在分泌（基底外侧至顶端）方向的极化转运，其外排比分别为 5.5±0.7 和 18.5±4.2。P-糖蛋白抑制剂如 valspodar 和 zosuquidar 不影响依托泊苷的转运，此外 PS20 降低了地高辛的分泌转运，但不影响依托泊苷。因此，依托泊苷的转运主要是由 MRP2 介导的，并被用作研究药物赋形剂的探针。尽管初步研究表明，大多数非离子型表面活性剂能够改变荧光 5-氯甲基荧光素（CMF）的 MRP2 介导的外排，但非离子型表面活性剂并未调节 MRP2 过表达的 MDCKII 细胞完整细胞单层上的依托泊苷转运。结论：环孢素 A（MRP2 和 P-糖蛋白的抑制剂）可调节依托泊苷在 MDCKII MRP2 细胞中的转运，但特异性 P-糖蛋白抑制剂（valspodar 和 zosuquidar）不能调节，这表明依托泊苷的转运主要受 MRP2 影响。此外，常用的非离子型表面活性剂不会降低 MDCKII MRP2 细胞中 MRP2 介导的依托泊苷转运。这些结果表明，MDCKII MRP2 细胞中的依托泊苷转运是研究 MRP2 相互作用的模型系统，并且表面活性剂通过抑制 MRP2 转运活性增加药物口服生物利用度的潜力可能不大。
