Barilli Amelia, Visigalli Rossana, Ferrari Francesca, Di Lascia Maria, Riccardi Benedetta, Puccini Paola, Dall'Asta Valeria, Rotoli Bianca Maria
Laboratory of General Pathology, Department of Medicine and Surgery, University of Parma, 43125 Parma, Italy.
Preclinical Pharmacokinetics, Biochemistry & Metabolism Department, Chiesi Farmaceutici, 43122 Parma, Italy.
Biomedicines. 2020 May 19;8(5):127. doi: 10.3390/biomedicines8050127.
Organic cation transporters (OCTs) and novel organic cation transporters (OCTNs) are responsible for drug delivery in the intestine and kidney; in the lung, OCTs mediate inhaled drugs' transport, although their physiological role in airways remains poorly understood. The studies addressing OCTs/OCTNs in human airways were mostly performed in immortal or transformed cell lines; here, we studied OCTs in EpiAirway™, a recently developed in vitro model of normal bronchial epithelium. Calu-3 monolayers were used for comparison. The activity of OCTs was evaluated by measuring the uptake of 1-methyl-4-phenylpyridinium (MPP) at the apical and basolateral side of monolayers and protein expression through Western Blot analysis. OCTs and OCTNs expression, along with that of Amino acid Transporter B (ATB)transporter, was determined by measuring the number of mRNA molecules through quantitative Polymerase Chain Reaction (qPCR). The interaction of the transporters with bronchodilators was also assessed. Results highlight significant differences between Calu-3 cells and EpiAirway™, since, in the latter, OCTs are active only on the basolateral membrane where they interact with the bronchodilator ipratropium. No activity of OCTs is detectable at the apical side; there, the most abundant carrier is, instead, /ATB, that can thus be potentially listed among organic cation transporters responsible for drug delivery in the lung.
有机阳离子转运体（OCTs）和新型有机阳离子转运体（OCTNs）负责药物在肠道和肾脏中的转运；在肺部，OCTs介导吸入药物的转运，尽管它们在气道中的生理作用仍知之甚少。针对人类气道中OCTs/OCTNs的研究大多在永生化或转化细胞系中进行；在此，我们在EpiAirway™（一种最近开发的正常支气管上皮体外模型）中研究了OCTs。使用Calu-3单层细胞进行比较。通过测量单层细胞顶端和基底外侧1-甲基-4-苯基吡啶鎓（MPP）的摄取以及通过蛋白质印迹分析评估蛋白质表达来评价OCTs的活性。通过定量聚合酶链反应（qPCR）测量mRNA分子数量来确定OCTs、OCTNs以及氨基酸转运体B（ATB）转运体的表达。还评估了转运体与支气管扩张剂的相互作用。结果突出了Calu-3细胞和EpiAirway™之间的显著差异，因为在后者中，OCTs仅在基底外侧膜上具有活性，在那里它们与支气管扩张剂异丙托溴铵相互作用。在顶端侧未检测到OCTs的活性；相反，那里最丰富的载体是/ATB，因此它可能被列为负责肺部药物转运的有机阳离子转运体之一。
