Sulindac and Its Metabolites Inhibit Multiple Transport Proteins in Rat and Human Hepatocytes

Abstract

Sulindac is a commonly used nonsteroidal anti-inflammatory drug. This study tested the hypothesis that sulindac-mediated drug-drug interactions and/or hepatotoxicity may be caused, in part, by inhibition of proteins responsible for the hepatic transport of drugs and/or bile acids by sulindac and/or sulindac metabolites [sulindac sulfone (S-sulfone) and sulindac sulfide (S-sulfide)]. The uptake and excretion of model substrates, [3 H]estradiol 17-␤-glucuronide (E217G), and nitrofurantoin (NF), were investigated in rat and human suspended and sandwich-cultured hepatocytes (SCH). In suspended rat hepatocytes, S-sulfone and S-sulfide inhibited Na ϩ -dependent TC initial uptake (IC 50 of 24.9 Ϯ 6.4 and 12.5 Ϯ 1.8 M, respectively) and Na ϩ -independent E217G initial uptake (IC 50 of 12.1 Ϯ 1.6 and 6.3 Ϯ 0.3 M, respectively). In rat SCH, sulindac metabolites (100 M) decreased the in vitro biliary clearance (Cl biliary ) of TC, E217G, and NF by 38 to 83%, 81 to 97%, and 33 to 57%, respectively; S-sulfone and S-sulfide also decreased the TC and NF biliary excretion index by 39 to 55%. In suspended human hepatocytes, S-sulfone and S-sulfide inhibited Na ϩ -dependent TC initial uptake (IC 50 of 42.2 and 3.1 M, respectively); S-sulfide also inhibited the TC Cl biliary in human SCH. Sulindac/metabolites markedly inhibited hepatic uptake and biliary excretion of E217G by 51 to 100% in human SCH. In conclusion, sulindac and metabolites are potent inhibitors of the uptake and biliary clearance of bile acids in rat and human hepatocytes and also inhibit substrates of rat breast cancer resistance protein, rat and human organic anion-transporting polypeptides, and human multidrug resistance-associated protein 2. Inhibition of multiple hepatic transport proteins by sulindac/metabolites may play an important role in clinically significant sulindac-mediated drug-drug interactions and/or liver injury.

Influence of Non-Steroidal Anti-Inflammatory Drugs on Organic Anion Transporting Polypeptide (OATP) 1B1- and OATP1B3-Mediated Drug Transport

“…To date, knowledge about the uptake of NSAIDs from blood into hepatocytes is limited. It has been demonstrated in rats that the uptake transporter Oat2 (Slc22a7) is involved in the hepatic uptake of ketoprofen (Morita et al, 2005), and recently it has been shown that sulindac and its metabolites inhibited multiple transport proteins in primary rat and human hepatocytes as tested with model substrates, e.g., taurocholate and estradiol-17␤-glucuronide (Lee et al, 2010). To date, the molecular mechanisms of NSAID uptake into hepatocytes are largely unknown.…”

Identification of modulated mRNAs and proteins in human primary hepatocytes treated with non-steroidal anti-inflammatory drugs

“…ABCB1 is found in the canalicular surface of hepatocytes when they excrete drugs directly into the bile 15 . a previous study has reported that multiple hepatic transport proteins including aTP-binding cassette, sub-family C, member 2 (ABCC2) are inhibited by sulindac/metabolites, therefore impairing hepatic transport of bile acid by sulindac/metabolites and disturbing bile acid homeostasis, resulting in sulindac-mediated liver injury 10 . in our experiment, ABCC2 was one of the 29 differentially expressed genes between the sulindacdiclofenac group and other nSaiD groups.…”

“…The transcriptional increases of these genes might reflect disturbance in hepatic transport. The expression of 'transport'-related genes might be caused by inhibition of proteins responsible for hepatic transport of drugs and/or bile acid by sulindac 10 . Both sulindac and diclofenac could regulate lipid metabolism-related genes as other hepatotoxicants.…”

Strategies for Minimisation of the Cholestatic Liver Injury Liability Posed by Drug-Induced Bile Salt Export Pump (BSEP) Inhibition

“…Many of the tested drugs exhibit high plasma protein binding; therefore, the true in vitro IC 50 values are likely to be much lower than the apparent values that were calculated. Furthermore, many drugs accumulate within hepatocytes at concentrations that are much higher than extracellular concentrations [95] and for some drugs it has been found that their metabolites (which are not produced in the membrane vesicle assay model) are more potent BSEP inhibitors than the parent compounds (e.g., troglitazone [89], sulindac [96]) and/or that BSEP inhibition requires co-expression of MRP2 (which is not present in insect cells transfected with BSEP) [32]. In addition, the fraction of transport inhibition required to cause functional alterations in bile flow in vivo that contribute to DILI progression following long-term dosing with drugs is unknown and could be much lower than the observed IC 50 values (e.g., IC 10 values).…”