Screening of OATP1B1/3 and OCT1 inhibitors in cryopreserved hepatocytes in suspension

• Published in: European journal of pharmaceutical sciences 2010-07, Vol.40 (4), p.282-288
• Main Authors: Badolo, Lassina, Rasmussen, Louise Munk, Hansen, Helle Rüsz, Sveigaard, Christina
• Format: Article
• Language: English
• Subjects: 1-Methyl-4-phenylpyridinium - pharmacokinetics; Animals; Bepridil - pharmacology; Biological and medical sciences; Biological Transport - drug effects; Capsaicin - analogs & derivatives; Capsaicin - pharmacology; Cryopreservation; Cyproheptadine - pharmacology; Dantrolene - pharmacology; Drug Evaluation, Preclinical; Drug Interactions; Enzyme Inhibitors - pharmacology; Estradiol - analogs & derivatives; Estradiol - pharmacokinetics; General pharmacology; Hepatocytes; Hepatocytes - drug effects; Hepatocytes - enzymology; Hepatocytes - metabolism; Humans; Inhibition; Isoenzymes - antagonists & inhibitors; Medical sciences; OATP; OCT1; Organic Anion Transporters - antagonists & inhibitors; Organic Anion Transporters, Sodium-Independent - antagonists & inhibitors; Pharmaceutical technology. Pharmaceutical industry; Pharmacology. Drug treatments; Rats; Screening; Solute Carrier Organic Anion Transporter Family Member 1b1; Solute Carrier Organic Anion Transporter Family Member 1B3; Species Specificity; Structure-Activity Relationship; Transporters
• ISSN: 0928-0987; 1879-0720
• DOI: 10.1016/j.ejps.2010.03.023

Drug–drug interactions involving hepatic drug transporters may have clinical consequences and jeopardize development of promising drug candidates. Organic anion transporting polypeptides (OATP/Oatp) and the organic cation transporters (OCT/Oct) are among the most important transporters involved in xenobiotic uptake in the liver. In the present study, 179 molecules have been tested as inhibitors of the uptake of estradiol-17βD-glucuronide (E 217βG), substrate of OATP1B1/3 (rOatp), or 1-methyl-4-phenylpyridinium (MPP+), substrate of OCT1 (rOct1), into suspended cryopreserved hepatocytes from humans and rats. Uptake was assessed in 96-well plates by measuring intracellular accumulation of radioactive substrate in hepatocytes in presence or absence of inhibitor. In rat hepatocytes 140 compounds were identified as inhibitors (inhibition at 20 μM ≥ 30%) of E 217βG uptake and 77 compounds inhibitors of MPP+ uptake. The most potent inhibitors of rOatp and rOct1 were dantrolene sodium ( K i = 2 ± 9 μM) and bepridil ( K i = 14 ± 2 μM), respectively. In human hepatocytes, the most potent inhibitors of E 217βG and MPP+ uptake were capsazepine ( K i = 14 ± 5 μM) and cyproheptadine ( K i = 19 ± 3 μM), respectively. Structure–activity relationship (SAR) analysis of all tested compounds suggested that lipophilicity, polarity, p K a and the number of hydrogen bond donors and acceptors play a role in their interaction with the transporters investigated. The method used here is a simple tool to screen large number of compounds as inhibitors of the uptake of substrates into suspended hepatocytes.