CHO/hPEPT1 cells overexpressing the human peptide transporter (hPEPT1) as an alternative in vitro model for peptidomimetic drugs.
CHO/hPEPT1 cells overexpressing the human peptide transporter (hPEPT1) as an alternative in vitro model for peptidomimetic drugs.
复制标题
过表达人肽转运蛋白 (hPEPT1) 的 CHO/hPEPT1 细胞作为拟肽药物的替代体外模型。
DOI：
10.1021/js980132e
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发表时间：
1999
影响因子：
3.8
通讯作者：
Amidon,GL
中科院分区：
文献类型：
--
作者：
Han,HK;Rhie,JK;Oh,DM;Saito,G;Hsu,CP;Stewart,BH;Amidon,GL
本研究的特点是中国仓鼠卵巢细胞过表达的人肠肽转运蛋白，CHO/hPEPT 1细胞，作为拟肽药物的体外模型。在未转染CHO细胞（CHO-K1）、转染CHO细胞（CHO/hPEPT 1）和Caco-2细胞三种不同的细胞培养体系中测定了Gly-Sar的摄取动力学参数，Vmaxin CHO/hPEPT 1细胞的摄取动力学参数约为Caco-2细胞和CHO-K1细胞的3倍，而Km值在所有情况下相似。CHO/hPEPT 1细胞对β-内酰胺类抗生素的摄取量是CHO-K1细胞的3 ~ 12倍，表明CHO/hPEPT 1细胞显著增强了肽转运活性。然而，由于氨基酸转运蛋白的高背景水平，氨基酸药物在CHO-K1和CHO/hPEPT 1细胞中也表现出高细胞摄取。因此，CHO/hPEPT 1细胞中的细胞摄取研究不足以区分肽基药物和氨基酸药物。CHO/hPEPT 1细胞作为拟肽药物体外模型的潜力也通过对Gly-Sar摄取的抑制研究进行了检查。拟肽药物如β-内酰胺类抗生素和依那普利显著抑制Gly-Sar摄取，而非肽基化合物l-多巴和α-甲基多巴在治疗浓度内不与Gly-Sar竞争细胞摄取。总之，本研究证明了CHO/hPEPT 1细胞作为摄取模型以及抑制研究的进一步表征，并表明其可用作靶向hPEPT 1转运蛋白的候选药物的替代体外模型。
The present study characterized Chinese hamster ovary cells overexpressing a human intestinal peptide transporter, CHO/hPEPT1 cells, as an in vitro model for peptidomimetic drugs. The kinetic parameters of Gly-Sar uptake were determined in three different cell culture systems such as untransfected CHO cells (CHO–K1), transfected CHO cells (CHO/hPEPT1) and Caco-2 cells.Vmaxin CHO/hPEPT1 cells was approximately 3-fold higher than those in Caco-2 cells and CHO–K1 cells, whileKmvalues were similar in all cases. The uptake ofβ-lactam antibiotics in CHO/hPEPT1 cells was three to twelve fold higher than that in CHO–K1 cells, indicating that CHO/hPEPT1 cells significantly enhanced the peptide transport activity. However, amino acid drugs also exhibited high cellular uptake in both CHO–K1 and CHO/hPEPT1 cells due to the high background level of amino acid transporters. Thus, cellular uptake study in CHO/hPEPT1 cells is not sensitive enough to distinguish the peptidyl drugs from amino acid drugs. The potential of CHO/hPEPT1 cells as an in vitro model for peptidomimetic drugs was also examined through the inhibition study on Gly-Sar uptake. Peptidomimetic drugs such asβ-lactam antibiotics and enalapril significantly inhibited Gly-Sar uptake whereas the nonpeptidyl compounds,l-dopa andα-methyldopa, did not compete with Gly-Sar for cellular uptake within the therapeutic concentrations. In conclusion, the present study demonstrates the further characterization of CHO/hPEPT1 cells as an uptake model as well as inhibition study and suggests their utility as an alternative in vitro model for drug candidates targeting the hPEPT1 transporter.