Evaluation of para -Aminosalicylic Acid as a Substrate of Multiple Solute Carrier Uptake Transporters and Possible Drug Interactions with Nonsteroidal Anti-inflammatory Drugs In Vitro

Abstract

para-Aminosalicylic acid (PAS) is a second-line antituberculosis drug that has been used to treat multidrug-resistant and extensively drug-resistant tuberculosis for more than 60 years. Renal secretion and glomerular filtration are the major pathways for the elimination of PAS. We comprehensively studied PAS transport by using cell lines that overexpressed various transporters and found that PAS acts as a novel substrate of an organic anionic polypeptide (OATP1B1), organic cationic transporters (OCT1 and OCT2), and organic anion transporters (OAT1 and OAT3) but is not a substrate of any ATP-binding cassette (ABC) transporters. Net PAS uptake was measured, and the transport affinities (K m values) for OATP1B1, OCT1, OCT2, OAT1, and OAT3 were found to be 50.0, 20.3, 28.7, 78.1, and 100.1 M, respectively. The net uptake rates suggested that renal OAT1 and OAT3 play relatively major roles in PAS elimination. The representative inhibitors rifampin for OATP1B1, probenecid for OAT1 and OAT3, and verapamil for OCT1 and OCT2 greatly inhibited PAS uptake, suggesting that PAS is dependent on multiple transporters for uptake. We also evaluated nonsteroidal anti-inflammatory drugs (NSAIDs), proton pump inhibitors (PPIs), and metformin for the inhibition of PAS uptake via these transporters. Half-maximal (50%) inhibitory concentrations (IC 50 s) were kinetically determined and used to predict the drug-drug interactions (DDIs) affecting these transporters' activity toward PAS. We found that rifampin, probenecid, ibuprofen, naproxen, cimetidine, and quinidine each exhibited a significant potential for in vivo DDIs with PAS. In this study, PAS was found to be a novel substrate of several transporters, and drugs that inhibit these transporters can reduce PAS elimination.

Comprehensive Substrate Characterization of 22 Antituberculosis Drugs for Multiple Solute Carrier (SLC) Uptake Transporters In Vitro

“…Namely, ethambutol, amoxicillin, isoniazid, and prothionamide were the most key findings for multiple SLC uptake transporters ( Table 1). The transport characteristics of these drugs were found to be close to similar to those we recently reported for PAS (33). Interestingly, ethambutol uptake was mediated by multiple cation transporters, such as OCT1, OCT2, OCTN1, and OCTN2 (Fig.…”

“…Isoniazid-induced anion gap acidosis has been well reported, indicating the capability of isoniazid to interact with anion transporters to accumulate anion (38). We recently reported the substrate potential of PAS, including potential DDIs with nonsteroidal anti-inflammatory drugs and proton pump inhibitors (33). With the exception of PAS, ethambutol, isoniazid, prothionamide, and amoxicillin, the anti-TB drugs were found to have negligible uptake into transporter-overexpressing cells, indicating that they were not substrates for the tested SLC membrane transporters ( Fig.…”

The pharmacokinetics of para‐aminosalicylic acid and its relationship to efficacy and intolerance

“…21,23 A recent in vitro study reported PAS to be a substrate of multiple organic and cation transporters. 64 In this study, nonsteroidal anti-inflammatory drugs such as diclofenac and indomethacin, and proton pump inhibitors such omeprazole inhibit PAS uptake through OAT1 and OAT3 inhibition. 64 Similarly, in vitro study showed metformin inhibits OCT1 and OCT2 the failure of PAS in combination with either SM or INH to protect these companion drugs against resistance emergence at low PAS concentrations of 10 μg/mL, but that PAS concentrations of 100 μg/mL were effective in preventing emergence of resistant organisms.…”

Development of a Physiologically Based Pharmacokinetic Model of Ethionamide in the Pediatric Population by Integrating Flavin‐Containing Monooxygenase 3 Maturational Changes Over Time

“…Transport experiments were conducted in accordance with our previously published method . Briefly, porcine kidney‐derived cell line (LLC‐PK1)‐P‐gp, Madin‐Darby canine kidney II (MDCKII)‐MRP1, and MDCKII‐MRP2 were seeded at a density of 2.5 × 10 5 cells per well in 24‐well plates and cultured for 5 days to reach sufficient confluency.…”

“…Transport experiments were conducted in accordance with our previously published method. 21 Briefly, porcine kidney-derived cell line (LLC-PK1)-P-gp, Madin-Darby canine kidney II (MDCKII)-MRP1, and MDCKII-MRP2 were seeded at a density of 2.5 × 10 5 cells per well in 24-well plates and cultured for 5 days to reach sufficient confluency. The kinetic parameters K m and V max were calculated using a concentration-dependent bidirectional transport assay for LLC-PK1-P-gp, MDCKII-MRP1, and MDCKII-MRP2, as summarized in Table 2.…”