Inhibition of Methotrexate Uptake via Organic Anion Transporters OAT1 and OAT3 by Glucuronides of Nonsteroidal Anti-inflammatory Drugs

Risk factors associated with high-dose methotrexate induced toxicities

INTRODUCTION

High-dose methotrexate (HDMTX) therapy poses challenges in various neoplasms due to individualized pharmacokinetics and associated adverse effects. Our purpose is to identify early risk factors associated with HDMTX-induced toxicities, paving the way for personalized treatment.

AREAS COVERED

A systematic review of PubMed and Cochrane databases was conducted for articles from inception to July 2023. Eligible studies included reviews, clinical trials, and real-world analyses. Irrelevant studies were excluded, and manual searches and citation reviews were performed. Factors such as MTX exposure, drug interactions, demographics, serum albumin, urine pH, serum calcium, and genetic polymorphisms affecting MTX transport (e.g. SLCO1B1), intracellular folate metabolism (MTHFR), cell development (ARID5B), metabolic pathways (UGT1A1, PNPLA3), as well as epigenetics were identified.

EXPERT OPINION

This comprehensive review aids researchers and clinicians in early identification of HDMTX toxicity risk factors. By understanding the multifaceted risk factors associated with hematologic malignancies, personalized treatment approaches can be tailored to optimize therapeutic outcomes.

Drug-drug interaction assessment based on a large-scale spontaneous reporting system for hepato- and renal-toxicity, and thrombocytopenia with concomitant low-dose methotrexate and analgesics use

BACKGROUND

Methotrexate (MTX) is the cornerstone of rheumatoid arthritis (RA) treatment and is highly effective with low-dose intermittent administration. MTX is occasionally used in combination with non-steroidal anti-inflammatory drugs (NSAIDs) and acetaminophen (APAP)/paracetamol for pain or inflammation control. With MTX treatment, the side effects, such as hepatotoxicity, renal failure, and myelosuppression should be considered. These are also seen with analgesics treatment.

METHODS

We used a large spontaneously reported adverse event database (FAERS [JAPIC AERS]) to analyze whether the reporting of adverse events increased upon MTX and analgesic therapy in patients with RA.

RESULTS

After identifying RA cases, the crude reporting odds ratios (cRORs) for hepatotoxicity, renal failure, and thrombocytopenia associated with the use of MTX, APAP, or NSAIDs were calculated by disproportionality analysis, which revealed significantly higher cRORs for these events. No analgesics showed consistent positive signals for drug-drug interaction (DDI) with concomitant low-dose MTX analyzed using four algorithms for DDI interaction (the Ω shrinkage measure, additive or multiplicative, and combination risk ratio models). However, in renal failure and thrombocytopenia, loxoprofen (Ω025 = 0.08) and piroxicam (Ω025 = 0.46), and ibuprofen (Ω025 = 0.74) and ketorolac (Ω025 = 3.52), respectively, showed positive signals in the Ω shrinkage measure model, and no consistency was found among adverse events or NSAIDs.

CONCLUSIONS

Studies using spontaneous reporting systems have limitations such as reporting bias or lack of patient background; however, the results of our comprehensive analysis support the results of previous clinical or epidemiological studies. This study also demonstrated the usefulness of FAERS for DDI assessment.

Amino acid derivative of probenecid potentiates apoptosis-inducing effects of vinblastine by increasing oxidative stress in a cancer cell-specific manner

Many chemotherapeutic drugs suffer from multidrug resistance (MDR). Efflux transporters, namely ATP-binding cassettes (ABCs), that pump the drugs out of the cancer cells comprise one major reason behind MDR. Therefore, ABC inhibitors have been under development for ages, but unfortunately, without clinical success. In the present study, an l-type amino acid transporter 1 (LAT1)-utilizing derivative of probenecid (PRB) was developed as a cancer cell-targeted efflux inhibitor for P-glycoprotein (P-gp), breast cancer resistant protein (BCRP) and/or several multidrug resistant proteins (MRPs), and its ability to increase vinblastine (VBL) cellular accumulation and apoptosis-inducing effects were explored. The novel amino acid derivative of PRB (2) increased the VBL exposure in triple-negative human breast cancer cells (MDA-MB-231) and human glioma cells (U-87MG) by 10-68 -times and 2-5-times, respectively, but not in estrogen receptor-positive human breast cancer cells (MCF-7). However, the combination therapy had greater cytotoxic effects in MCF-7 compared to MDA-MB-231 cells due to the increased oxidative stress recorded in MCF-7 cells. The metabolomic study also revealed that compound 2, together with VBL, decreased the transport of those amino acids essential for the biosynthesis of endogenous anti-oxidant glutathione (GSH). Moreover, the metabolic differences between the outcomes of the studied breast cancer cell lines were explained by the distinct expression profiles of solute carriers (SLCs) that can be concomitantly inhibited. Therefore, attacking several SLCs simultaneously to change the nutrient environment of cancer cells can serve as an adjuvant therapy to other chemotherapeutics, offering an alternative to ABC inhibitors.

Potential Involvement of Organic Anion Transporters in Drug Interactions with Shuganning Injection, a Traditional Chinese Patent Medicine

Traditional Chinese medicine injections have been widely used in China for the treatment of various diseases. Transporter-mediated drug-drug interactions are a major contributor to adverse drug reactions. However, the research on transporter-mediated Traditional Chinese medicine injection-drug interactions is limited. Shuganning injection is a widely used Traditional Chinese medicine injection for treating various liver diseases. In this study, we investigated the inhibitory effect of Shuganning injection and its four main ingredients (baicalin, geniposide, chlorogenic acid, and oroxylin A) on 9 drug transporters. Shuganning injection strongly inhibited organic anion transporter 1 and organic anion transporter 3 with IC50 values < 0.1% (v/v), and moderately inhibited organic anion transporter 2, organic anion transporting-polypeptide 1B1, and organic anion transporting-polypeptide 1B3 with IC50 values < 1.0%. Baicalin, the most abundant bioactive ingredient in the Shuganning injection, was identified as both an inhibitor and substrate of organic anion transporter 1, organic anion transporter 3, and organic anion transporting-polypeptide 1B3. Oroxylin A had the potential to act as both an inhibitor and substrate of organic anion transporting-polypeptide 1B1 and organic anion transporting-polypeptide 1B3. In contrast, geniposide and chlorogenic acid had no significant inhibitory effect on drug transporters. Notably, Shuganning injection markedly altered the pharmacokinetics of furosemide and atorvastatin in rats. Using Shuganning injection as an example, our findings support the implementation of transporter-mediated Traditional Chinese medicine injection-drug interactions in the development of Traditional Chinese medicine injection standards.

Recent Advances in Synthetic Drugs and Natural Actives Interacting with OAT3

Organic anion transporter 3 (OAT3) is predominantly expressed in the kidney and plays a vital role in drug clearance. Consequently, co-ingestion of two OAT3 substrates may alter the pharmacokinetics of the substrate. This review summarizes drug-drug interactions (DDIs) and herbal-drug interactions (HDIs) mediated by OAT3, and inhibitors of OAT3 in natural active compounds in the past decade. This provides a valuable reference for the combined use of substrate drugs/herbs for OAT3 in clinical practice in the future and for the screening of OAT3 inhibitors to avoid harmful interactions.

A critical review of methotrexate clinical interactions: role of transporters

INTRODUCTION

Methotrexate (MTX) is an anti-folate and immunosuppressive drug prescribed for various malignancies and immune diseases. However, delayed elimination of MTX associated with concomitant use of some medications can lead to severe and life-threatening adverse effects.

AREAS COVERED

This paper investigated drug-MTX interactions that lead to elevated MTX levels and related adverse effects due to the role of transporters. Methotrexate toxicity occurs at both low and high doses administrations. According to the studies we reviewed in this paper, most interaction records with methotrexate occurred with co-administration of indomethacin, ketoprofen, omeprazole, piperacillin/tazobactam, ciprofloxacin, co-trimoxazole, probenecid, and imatinib, mainly due to the role of transporters. However, most studies were performed as case reports or series, and confirming the exact drug-methotrexate interaction still needs further clinical investigations.

EXPERT OPINION

Our findings showed no firm evidence of interactions of proton pump inhibitors (PPIs), levetiracetam, and NSAIDS with MTX. Moreover, patients' risk factors, hypoalbuminemia, renal failure, third space fluid retention, the elderly, polypharmacy, and transport inhibition are the most critical factors for MTX toxicity. If substitution or temporary discontinuation is not possible, healthcare providers should be aware of interactions, especially in patients with risk factors for MTX toxicity.

Kidney Drug Transporters in Pharmacotherapy

The kidney functions not only as a metabolite elimination organ but also plays an important role in pharmacotherapy. The kidney tubule epithelia cells express membrane carriers and transporters, which play an important role in drug elimination, and can determine drug nephrotoxicity and drug-drug interactions, as well as constituting direct drug targets. The above aspects of kidney transport proteins are discussed in the review.

The Role of Solute Carrier Transporters in Efficient Anticancer Drug Delivery and Therapy

Transporter-mediated drug resistance is a major obstacle in anticancer drug delivery and a key reason for cancer drug therapy failure. Membrane solute carrier (SLC) transporters play a crucial role in the cellular uptake of drugs. The expression and function of the SLC transporters can be down-regulated in cancer cells, which limits the uptake of drugs into the tumor cells, resulting in the inefficiency of the drug therapy. In this review, we summarize the current understanding of low-SLC-transporter-expression-mediated drug resistance in different types of cancers. Recent advances in SLC-transporter-targeting strategies include the development of transporter-utilizing prodrugs and nanocarriers and the modulation of SLC transporter expression in cancer cells. These strategies will play an important role in the future development of anticancer drug therapies by enabling the efficient delivery of drugs into cancer cells.

CP-25 enhances OAT1-mediated absorption of methotrexate in synoviocytes of collagen-induced arthritis rats

Organic anion transporter 1 (OAT1) plays a major role in mediating the absorption, distribution and excretion of drugs and other xenobiotics in the human body. In this study we explored the OAT1 status in rheumatoid arthritis (RA) patients and arthritic animals and its role in regulating the anti-arthritic activity of methotrexate (MTX). We showed that OAT1 expression was significantly downregulated in synovial tissues from RA patients compared with that in the control patients. In collagen-induced arthritis (CIA) rats, synovial OAT1 expression was significantly decreased compared with the control rats. In synoviocytes isolated from CIA rats, PGE2 (0.003-1.75 μM) dose-dependently downregulated OAT1 expression, resulting in decreased absorption of MTX. Silencing OAT1 in synoviocytes caused a 43.7% reduction in the uptake of MTX. Furthermore, knockdown of OAT1 impaired MTX-induced inhibitory effects on the viability and migration of synoviocytes isolated from CIA rats. Moreover, injection of OAT1-shRNA into articular cavity of CIA rats significantly decreased synovial OAT1 expression and impaired the anti-arthritic action of MTX, while injection of lentivirus containing OAT1 sequences led to the opposite results. Interestingly, we found that paeoniflorin-6'-O-benzene sulfonate (CP-25) upregulated OAT1 expression both in vitro and in vivo and promoted MTX uptake by synoviocytes via regulating OAT1 expression and function. Taken together, OAT1 plays a major role in regulating MTX uptake by synoviocytes and the anti-arthritic activity of MTX. OAT1 is downregulated in RA and CIA rats, which can be improved by CP-25.

The Interplay between Uremic Toxins and Albumin, Membrane Transporters and Drug Interaction

Uremic toxins are a heterogeneous group of molecules that accumulate in the body due to the progression of chronic kidney disease (CKD). These toxins are associated with kidney dysfunction and the development of comorbidities in patients with CKD, being only partially eliminated by dialysis therapies. Importantly, drugs used in clinical treatments may affect the levels of uremic toxins, their tissue disposition, and even their elimination through the interaction of both with proteins such as albumin and cell membrane transporters. In this context, protein-bound uremic toxins (PBUTs) are highlighted for their high affinity for albumin, the most abundant serum protein with multiple binding sites and an ability to interact with drugs. Membrane transporters mediate the cellular influx and efflux of various uremic toxins, which may also compete with drugs as substrates, and both may alter transporter activity or expression. Therefore, this review explores the interaction mechanisms between uremic toxins and albumin, as well as membrane transporters, considering their potential relationship with drugs used in clinical practice.

The Role of Uptake and Efflux Transporters in the Disposition of Glucuronide and Sulfate Conjugates

Glucuronidation and sulfation are the most typical phase II metabolic reactions of drugs. The resulting glucuronide and sulfate conjugates are generally considered inactive and safe. They may, however, be the most prominent drug-related material in the circulation and excreta of humans. The glucuronide and sulfate metabolites of drugs typically have limited cell membrane permeability and subsequently, their distribution and excretion from the human body requires transport proteins. Uptake transporters, such as organic anion transporters (OATs and OATPs), mediate the uptake of conjugates into the liver and kidney, while efflux transporters, such as multidrug resistance proteins (MRPs) and breast cancer resistance protein (BCRP), mediate expulsion of conjugates into bile, urine and the intestinal lumen. Understanding the active transport of conjugated drug metabolites is important for predicting the fate of a drug in the body and its safety and efficacy. The aim of this review is to compile the understanding of transporter-mediated disposition of phase II conjugates. We review the literature on hepatic, intestinal and renal uptake transporters participating in the transport of glucuronide and sulfate metabolites of drugs, other xenobiotics and endobiotics. In addition, we provide an update on the involvement of efflux transporters in the disposition of glucuronide and sulfate metabolites. Finally, we discuss the interplay between uptake and efflux transport in the intestine, liver and kidneys as well as the role of transporters in glucuronide and sulfate conjugate toxicity, drug interactions, pharmacogenetics and species differences.

Investigation of the arcane inhibition of human organic anion transporter 3 by benzofuran antiarrhythmic agents

The combination of antiarrhythmic agents, amiodarone or dronedarone, with the anticoagulant rivaroxaban is used clinically in the management of atrial fibrillation for rhythm control and secondary stroke prevention respectively. Renal drug-drug interactions (DDIs) between amiodarone or dronedarone and rivaroxaban were previously ascribed to inhibition of rivaroxaban secretion by P-glycoprotein at the apical membrane of renal proximal tubular epithelial cells. Benzbromarone, a known inhibitor of organic anion transporter 3 (OAT3), shares a benzofuran scaffold with amiodarone and dronedarone. However, inhibitory activity of amiodarone and dronedarone against OAT3 remains arcane. Here, we conducted in vitro transporter inhibition assays in OAT3-transfected HEK293 cells which revealed amiodarone, dronedarone and their respective major pharmacologically-active metabolites N-desethylamiodarone and N-desbutyldronedarone possess inhibitory activity against OAT3, with corrected K_i values of 0.042, 0.019, 0.028 and 0.0046 μM respectively. Protein binding effects and probe substrate dependency were accounted for in our assays. Static modelling predicted 1.29-, 1.01-, 1.29- and 1.16-fold increase in rivaroxaban exposure, culminating in a predicted 1.29-, 1.01-, 1.28- and 1.15-fold increase in major bleeding risk respectively, suggesting potential OAT3-mediated DDI between amiodarone and rivaroxaban. Future work involving physiologically-based pharmacokinetic modelling is crucial in holistically predicting the complex DDIs between the benzofuran antiarrhythmic agents and rivaroxaban.

Inhibitory effect of sixteen pharmaceutical excipients on six major organic cation and anion uptake transporters

To date, relatively little is known about the interactions of pharmaceutical excipients with hepatic and renal drug uptake transporters. The present study was designed to systematically evaluate the effects of 16 commonly consumed excipients on human organic cation transporter 1 and 2 (hOCT1 and hOCT2), human organic anion transporter 1 and 3 (hOAT1 and hOAT3) and human organic anion transporting polypeptide 1B1 and 1B3 (hOATP1B1 and hOATP1B3). The inhibitory effects and mechanisms of excipients on transporters were investigated using in vitro uptake studies, cell viability assays, concentration-dependent studies, and the Lineweaver-Burk plot method. Triton X-100 is a non-competitive inhibitor for all six transporters. Tween 20 inhibits hOCT2, hOAT1, hOAT3, and hOATP1B3 in a mixed way, whereas it competitively inhibits hOATP1B1. The inhibition of Tween 80 is competitive for hOCT2, non-competitive for hOATP1B1 and hOATP1B3, and mixed for hOAT1 and hOAT3. Concentration-dependent studies identify Triton X-100 as a strong inhibitor of hOCT1 and hOCT2 with IC₅₀ values of 20.1 and 4.54 μg/mL, respectively. Additionally, Triton X-100, Tween 20, and Tween 80 strongly inhibit hOAT3 with IC₅₀ values ≤31.0 μg/mL. The present study is significant in understanding the excipient-drug interactions and provides valuable information for excipient selection in drug development.

Drug Metabolites Potently Inhibit Renal Organic Anion Transporters, OAT1 and OAT3

Human OAT1 and OAT3 play major roles in renal drug elimination and drug-drug interactions. However, there is little information on the interactions of drug metabolites with transporters. The goal of this study was to characterize the interactions of drug metabolites with OAT1 and OAT3 and compare their potencies of inhibition with those of their corresponding parent drugs. Using HEK293 cells stably transfected with OAT1 and OAT3, 25 drug metabolites and their corresponding parent drugs were screened for inhibitory effects on OAT1-and OAT3-mediated 6-carboxyfluorescein uptake at a screening concentration of 200 μM for all but 3 compounds. 20 and 24 drug metabolites were identified as inhibitors (inhibition > 50%) of OAT1 and OAT3, respectively. Seven drug metabolites were potent inhibitors of either or both OAT1 and OAT3 with K_i values less than 1 μM. 22 metabolites were more potent inhibitors of OAT3 than OAT1. Importantly, one drug and four metabolites were predicted to inhibit OAT3 at unbound plasma concentrations achieved clinically (C_max,u/K_i values ≥ 0.1). In conclusion, our study highlights the potential interactions of drug metabolites with OAT1 and OAT3 at clinically relevant concentrations, suggesting that drug metabolites may modulate therapeutic and adverse drug response by inhibiting renal drug transporters.

The impact of anticancer drugs on the ocular surface

Cancer is a global health problem and is one of the leading causes of death worldwide. Pleasingly, the rate of survival has improved and continues in an upward trend mainly due to better diagnosis and treatment modalities. In particular, the development of anticancer drugs including cytotoxic chemotherapy, hormonal agents and targeted therapies have provided the most effective treatment options in combatting cancerous cells. However, the antineoplastic mechanisms of these drugs can also lead to undesirable systemic and ocular side effects resulting from cytotoxicity, inflammation and neurotoxicity. While survival rates are projected to increase with time, the number of patients presenting with these side effects that can substantially impact quality of life will also rise. The current paper reviews the ocular surface and adnexal side effects of anticancer drugs, the appropriate management and possible interactions between drugs for ocular surface pathology treatment and the anticancer drugs.

Transporter-Mediated Drug-Drug Interactions and Their Significance

Drug transporters are considered to be determinants of drug disposition and effects/toxicities by affecting the absorption, distribution, and excretion of drugs. Drug transporters are generally divided into solute carrier (SLC) family and ATP binding cassette (ABC) family. Widely studied ABC family transporters include P-glycoprotein (P-GP), breast cancer resistance protein (BCRP), and multidrug resistance proteins (MRPs). SLC family transporters related to drug transport mainly include organic anion-transporting polypeptides (OATPs), organic anion transporters (OATs), organic cation transporters (OCTs), organic cation/carnitine transporters (OCTNs), peptide transporters (PEPTs), and multidrug/toxin extrusions (MATEs). These transporters are often expressed in tissues related to drug disposition, such as the small intestine, liver, and kidney, implicating intestinal absorption of drugs, uptake of drugs into hepatocytes, and renal/bile excretion of drugs. Most of therapeutic drugs are their substrates or inhibitors. When they are comedicated, serious drug-drug interactions (DDIs) may occur due to alterations in intestinal absorption, hepatic uptake, or renal/bile secretion of drugs, leading to enhancement of their activities or toxicities or therapeutic failure. This chapter will illustrate transporter-mediated DDIs (including food drug interaction) in human and their clinical significances.

Targeted efflux transporter inhibitors - A solution to improve poor cellular accumulation of anti-cancer agents

Efflux transporters function as vacuum cleaners of xenobiotics and therefore they hinder drugs to reach their targets at effective enough concentrations. Efflux pump inhibitors can be used to improve the cell accumulation of drugs, however all the current inhibitors lack selectivity towards cancer cells. l-Type amino acid transporter 1 (LAT1), which is expressed in many types of cancer cells can be utilized to target inhibitors of efflux transporters to these cells by converting the inhibitors into LAT1-utilizing prodrugs. In this study, we prepared 5 LAT1-utilizing prodrugs of an efflux pump inhibitor, probenecid (PRB). All novel compounds were transported into human breast cancer cells (MCF-7) mainly via LAT1. The compounds also interacted with either multiresistant proteins (MRPs), P-glycoprotein (P-gp) or breast cancer resistant protein (BCRP) and increased significantly (3-4-fold) the cellular accumulation of anti-cancer agent vinblastine (VBL). Consequently, this improved the anti-proliferative efficacy of VBL by decreasing the cell growth after 72 h from 100% (VBL treatment alone) to 48-75% (combination treatment). However, the same phenomenon was not seen with other chemotherapeutic, methotrexate (MTX). Therefore, the chemotherapeutics need to be selected carefully based on their uptake mechanism to the combinations with LAT1-utilizing prodrugs of efflux pump inhibitors to defeat effectively the multidrug resistance (MDR) of chemotherapy.

Genetic Heterogeneity of SLC22 Family of Transporters in Drug Disposition. J Pers Med. 2018;8. [PMID: 29659532 PMCID: PMC6023491 DOI: 10.3390/jpm8020014]

An important aspect of modern medicine is its orientation to achieve more personalized pharmacological treatments. In this context, transporters involved in drug disposition have gained well-justified attention. Owing to its broad spectrum of substrate specificity, including endogenous compounds and xenobiotics, and its strategical expression in organs accounting for drug disposition, such as intestine, liver and kidney, the SLC22 family of transporters plays an important role in physiology, pharmacology and toxicology. Among these carriers are plasma membrane transporters for organic cations (OCTs) and anions (OATs) with a marked overlap in substrate specificity. These two major clades of SLC22 proteins share a similar membrane topology but differ in their degree of genetic variability. Members of the OCT subfamily are highly polymorphic, whereas OATs have a lower number of genetic variants. Regarding drug disposition, changes in the activity of these variants affect intestinal absorption and target tissue uptake, but more frequently they modify plasma levels due to enhanced or reduced clearance by the liver and secretion by the kidney. The consequences of these changes in transport-associated function markedly affect the effectiveness and toxicity of the treatment in patients carrying the mutation. In solid tumors, changes in the expression of these transporters and the existence of genetic variants substantially determine the response to anticancer drugs. Moreover, chemoresistance usually evolves in response to pharmacological and radiological treatment. Future personalized medicine will require monitoring these changes in a dynamic way to adapt the treatment to the weaknesses shown by each tumor at each stage in each patient.

Endogenous Metabolites-Mediated Communication Between OAT1/OAT3 and OATP1B1 May Explain the Association Between SLCO1B1 SNPs and Methotrexate Toxicity

Although OATP1B1 is not expressed in the kidney, polymorphisms in SLCO1B1 have been associated with methotrexate clearance or toxicity. This unexpected pharmacogenetic association may reflect remote communication between liver and kidney transporters. This study confirms the pharmacogenetic association with methotrexate toxicity in adult patients with hematological malignancies. Using a targeted urinary metabolomics approach, we identified 38 and 34 metabolites which were differentially excreted between wildtype and carriers of the c.388A>G or c.521T>C variant alleles, respectively, half of them being associated with methotrexate toxicity. These metabolites mainly consisted of fatty acid derivatives and microbiota catabolites, including glycine conjugates and other uremic toxins, all known OATs substrates. These results suggest that dysfunction of a transporter affects the excretion profile of endogenous or exogenous substrates, possibly through metabolite-mediated interactions involving other transport systems, even in distant organs. This opens the way for better comprehension of complex pharmacokinetics and transporter-mediated drug-drug or nutrient-drug interactions.