scholarly journals Trospium Chloride Transport by Mouse Drug Carriers of the Slc22 and Slc47 Families

2020 ◽  
Vol 22 (1) ◽  
pp. 22
Author(s):  
Matthias Gorecki ◽  
Simon F. Müller ◽  
Regina Leidolf ◽  
Joachim Geyer
Keyword(s):  
Knockout Mouse ◽  
Organic Cation ◽  
Chloride Transport ◽  
Drug Carriers ◽  
Hek293 Cells ◽  
Low Permeability ◽  
Organic Cation Transporters ◽  
Trospium Chloride ◽  
Individual Role ◽  
Positively Charged

Background: The muscarinic receptor antagonist trospium chloride (TCl) is used for pharmacotherapy of the overactive bladder syndrome. TCl is a hydrophilic positively charged drug. Therefore, it has low permeability through biomembranes and requires drug transporters for distribution and excretion. In humans, the organic cation transporters OCT1 and OCT2 and the multidrug and toxin extrusion MATE1 and MATE2-K carriers showed TCl transport. However, their individual role for distribution and excretion of TCl is unclear. Knockout mouse models lacking mOct1/mOct2 or mMate1 might help to clarify their role for the overall pharmacokinetics of TCl. Method: In preparation of such experiments, TCl transport was analyzed in HEK293 cells stably transfected with the mouse carriers mOct1, mOct2, mMate1, and mMate2, respectively. Results: Mouse mOct1, mOct2, and mMate1 showed significant TCl transport with Km values of 58.7, 78.5, and 29.3 µM, respectively. In contrast, mMate2 did not transport TCl but showed MPP+ transport with Km of 60.0 µM that was inhibited by the drugs topotecan, acyclovir, and levofloxacin. Conclusion: TCl transport behavior as well as expression pattern were quite similar for the mouse carriers mOct1, mOct2, and mMate1 compared to their human counterparts.

Abstract 14035: Renal Tubular Secretion and Cardiac Distribution of Dofetilide is Dependent on MATE1 Function

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Muhammad Erfan Uddin ◽  
Yan Jin ◽  
Alice A Gibson ◽  
Ingrid M Bonilla ◽  
Cynthia A Carnes ◽  
...  
Keyword(s):  
Organic Cation ◽  
Tubular Secretion ◽  
Hek293 Cells ◽  
Delayed Rectifier ◽  
Organic Cation Transporters ◽  
Wild Type ◽  
Renal Tubular Secretion ◽  
Cation Transporters ◽  
Renal Tubular

Introduction: Dofetilide is a delayed rectifier potassium channel inhibitor used to treat patients with atrial fibrillation and flutter, and its use is associated with a risk of QT prolongation and Torsades de Pointes . The mechanisms involved in dofetilide’s renal tubular secretion and its uptake into cardiomyocytes remain unknown. Previously reported drug-drug interaction (DDI) studies suggest the involvement of organic cation transporters. Here, we investigated the contribution of organic cation transporters (OCT2 and MATE1) to the pharmacokinetics of dofetilide to gain insight into its DDI potential. Hypothesis: Based on known DDIs with dofetilide, we hypothesize that OCT2 and/or MATE1 play a key role in the inter-individual variability in pharmacokinetics and pharmacodynamics of dofetilide. Methods: In vitro and ex vivo transport kinetics of dofetilide were determined in HEK293 cells stably transfected with OCT2 or MATE1, and in isolated cardiomyocytes, respectively. In vivo studies were performed in wild-type, OCT2-, and MATE1-deficient mice (n=5) receiving dofetilide (5 mg/kg, p.o., 2.5 mg/kg, i.v.), with or without several contraindicated drugs. Dofetilide concentrations in plasma and urine were determined by UPLC-MS/MS. Results: In vitro studies demonstrated that dofetilide is a good substrate of MATE1 but not OCT2. Deficiency of MATE1 was associated with increased plasma concentrations of dofetilide and with a significantly reduced urinary excretion (3-fold in females and 5-fold in males, respectively). Dofetilide accumulation in cardiomyocytes was increased by 2-fold in MATE1-deficient females, and pre-incubation with the MATE1 inhibitor cimetidine significantly reduced dofetilide uptake in wild-type cardiomyocytes. Several contraindicated drugs listed in the dofetilide prescribing information, including cimetidine, ketoconazole, increased dofetilide plasma exposure in wild-type mice by >2.8-fold. Conclusion: Renal secretion of dofetilide is mediated by MATE1 and is highly sensitive to inhibition by many widely used prescription drugs that can cause clinically relevant DDIs. Deficiency of MATE1 also increases accumulation in the heart which may contribute to individual variation in response to dofetilide.

scholarly journals Interaction Profiles of Central Nervous System Active Drugs at Human Organic Cation Transporters 1–3 and Human Plasma Membrane Monoamine Transporter

2021 ◽  
Vol 22 (23) ◽  
pp. 12995
Author(s):  
Thomas J. F. Angenoorth ◽  
Stevan Stankovic ◽  
Marco Niello ◽  
Marion Holy ◽  
Simon D. Brandt ◽  
...  
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Plasma Membrane ◽  
Human Plasma ◽  
Organic Cation ◽  
Hek293 Cells ◽  
Monoamine Transporters ◽  
Organic Cation Transporters ◽  
Monoamine Transporter ◽  
Cation Transporters

Many psychoactive compounds have been shown to primarily interact with high-affinity and low-capacity solute carrier 6 (SLC6) monoamine transporters for norepinephrine (NET; norepinephrine transporter), dopamine (DAT; dopamine transporter) and serotonin (SERT; serotonin transporter). Previous studies indicate an overlap between the inhibitory capacities of substances at SLC6 and SLC22 human organic cation transporters (SLC22A1–3; hOCT1–3) and the human plasma membrane monoamine transporter (SLC29A4; hPMAT), which can be classified as high-capacity, low-affinity monoamine transporters. However, interactions between central nervous system active substances, the OCTs, and the functionally-related PMAT have largely been understudied. Herein, we report data from 17 psychoactive substances interacting with the SLC6 monoamine transporters, concerning their potential to interact with the human OCT isoforms and hPMAT by utilizing radiotracer-based in vitro uptake inhibition assays at stably expressing human embryonic kidney 293 cells (HEK293) cells. Many compounds inhibit substrate uptake by hOCT1 and hOCT2 in the low micromolar range, whereas only a few substances interact with hOCT3 and hPMAT. Interestingly, methylphenidate and ketamine selectively interact with hOCT1 or hOCT2, respectively. Additionally, 3,4-methylenedioxymethamphetamine (MDMA) is a potent inhibitor of hOCT1 and 2 and hPMAT. Enantiospecific differences of R- and S-α-pyrrolidinovalerophenone (R- and S-α-PVP) and R- and S-citalopram and the effects of aromatic substituents are explored. Our results highlight the significance of investigating drug interactions with hOCTs and hPMAT, due to their role in regulating monoamine concentrations and xenobiotic clearance.

scholarly journals Overlap and Specificity in the Substrate Spectra of Human Monoamine Transporters and Organic Cation Transporters 1, 2, and 3

2021 ◽  
Vol 22 (23) ◽  
pp. 12816
Author(s):  
Lukas Gebauer ◽  
Ole Jensen ◽  
Maria Neif ◽  
Jürgen Brockmöller ◽  
Christof Dücker
Keyword(s):  
Organic Cation ◽  
Signal Transmission ◽  
Cell Uptake ◽  
Hek293 Cells ◽  
Monoamine Transporters ◽  
Organic Cation Transporters ◽  
Structural Determinants ◽  
Renal Drug Elimination ◽  
The Central Nervous System ◽  
Cation Transporters

Human monoamine transporters (MATs) are cation transporters critically involved in neuronal signal transmission. While inhibitors of MATs have been intensively studied, their substrate spectra have received far less attention. Polyspecific organic cation transporters (OCTs), predominantly known for their role in hepatic and renal drug elimination, are also expressed in the central nervous system and might modulate monoaminergic signaling. Using HEK293 cells overexpressing MATs or OCTs, we compared uptake of 48 compounds, mainly phenethylamine and tryptamine derivatives including matched molecular pairs, across noradrenaline, dopamine and serotonin transporters and OCTs (1, 2, and 3). Generally, MATs showed surprisingly high transport activities for numerous analogs of neurotransmitters, but their substrate spectra were limited by molar mass. Human OCT2 showed the broadest substrate spectrum, and also the highest overlap with MATs substrates. Comparative kinetic analyses revealed that the radiotracer meta-iodobenzylguanidine had the most balanced uptake across all six transporters. Matched molecular pair analyses comparing MAT and OCT uptake using the same methodology could provide a better understanding of structural determinants for high cell uptake by MATs or OCTs. The data may result in a better understanding of pharmacokinetics and toxicokinetics of small molecular organic cations and, possibly, in the development of more specific radiotracers for MATs.

Organic cation transporters OCT1, 2, and 3 mediate high-affinity transport of the mutagenic vital dye ethidium in the kidney proximal tubule

2009 ◽  
Vol 296 (6) ◽  
pp. F1504-F1513 ◽  
Author(s):  
Wing-Kee Lee ◽  
Markus Reichold ◽  
Bayram Edemir ◽  
Giuliano Ciarimboli ◽  
Richard Warth ◽  
...  
Keyword(s):  
Organic Cation ◽  
Fluorescent Dyes ◽  
Mouse Kidney ◽  
Proximal Tubules ◽  
Facilitated Diffusion ◽  
Organic Cation Transporters ◽  
High Affinity ◽  
Cation Transporters ◽  
Safety Guidelines ◽  
Positively Charged

The positively charged fluorescent dyes ethidium (Et+) and propidium (Pr2+) are widely used as DNA and necrosis markers. Et+is cytotoxic and mutagenic. The polyspecific organic cation transporters OCT1 (SLC22A1), OCT2 (SLC22A2), and OCT3 (SLC22A3) mediate electrogenic facilitated diffusion of small (≤500 Da) organic cations with broad specificities. In humans, OCT2 mediates basolateral uptake by kidney proximal tubules (PT), whereas in rodents OCT1/2 are involved. In mouse kidney, perfused Et+accumulated predominantly in the S2/S3 segments of the PT, but not Pr2+. In cells stably overexpressing human OCTs (hOCTs), Et+uptake was observed with Kmvalues of 0.8 ± 0.2 μM (hOCT1), 1.7 ± 0.5 μM (hOCT2), and 2.0 ± 0.5 μM (hOCT3), whereas Pr2+was not transported. Accumulation of Et+was inhibited by OCT substrates quinine, 3-methyl-4-phenylpyridinium (MPP+), cimetidine, and tetraethylammonium (TEA+). For hOCT1 and hOCT2, the IC50values for MPP+, TEA+, and cimetidine were higher than for inhibition of previously tested transported substrates. For hOCT2, the inhibition of Et+uptake by MPP+and cimetidine was shown to be competitive. Et+also inhibited transport of 0.1 μM [3H]MPP+by all hOCT isoforms with IC50values between 0.4 and 1.3 μM, and the inhibition of hOCT1-mediated uptake of MPP+by Et+was competitive. In Oct1/2−/−mice, Et+uptake in the PT was almost abolished. The data demonstrate that Et+is taken up avidly by the PT, which is mediated by OCT1 and/or OCT2. Considering the high affinity of OCTs for Et+and their strong expression in various organs, strict safety guidelines for Et+handling should be reinforced.

scholarly journals MOXIFLOXACIN IS A POTENTIN VITROINHIBITOR OF OCT- AND MATE-MEDIATED TRANSPORT OF METFORMIN AND ETHAMBUTOL

2016 ◽  
pp. AAC.01471-16 ◽  
Author(s):  
Lindsey H. M. te Brake ◽  
Jeroen J. M. W. van den Heuvel ◽  
Aaron Ohene Buaben ◽  
Reinout van Crevel ◽  
Albert Bilos ◽  
...  
Keyword(s):  
Organic Cation ◽  
Potent Inhibitor ◽  
Drug Uptake ◽  
Hek293 Cells ◽  
Organic Cation Transporters ◽  
Interaction Study ◽  
Inhibitory Effects ◽  
Mechanistic Basis

Introduction:It is largely unknown if simultaneous administration of tuberculosis (TB) drugs and metformin leads to drug-drug interactions (DDIs). Disposition of metformin is determined by organic cation transporters (OCTs) and multidrug and toxin extrusion proteins (MATEs). Thus any DDIs would primarily be mediated via these transporters. This study aimed to assess thein vitroinhibitory effects of TB drugs (rifampicin, isoniazid, pyrazinamide, ethambutol, amikacin, moxifloxacin and linezolid) on metformin transport, and whether TB drugs are also substrates themselves of OCTs and MATEs.Methods:HEK293 cells overexpressing OCT1, OCT2, OCT3, MATE1 and MATE2K were used to study TB drug-mediated inhibition of [14C]metformin uptake and to test if TB drugs are transporter substrates. Metformin uptake was determined by quantifying [14C]metformin radioactivity and TB drug uptake was analysed using LC-MS/MS. DDI-indices were calculated (plasma Cmax/IC50), and based on literature a cut-off of >0.1 was assumed to warrant furtherin vivoinvestigation.Results:Moxifloxacin was the only TB drug identified as a potent inhibitor (DDI-index>0.1) of MATE1- and MATE2K-mediated metformin transport (IC50of 12 μM (95% CI 5.1-29 μM) and 7.6 μM (95% CI 0.2-242 μM), respectively). Of all TB drugs, only ethambutol appeared to be a substrate of OCT1, OCT2, OCT3, MATE1 and MATE2K. MATE1-mediated ethambutol uptake was inhibited strongly (DDI-index >0.1) by moxifloxacin (IC5012 μM (95% CI 3.4-43 μM)).Conclusions:Our findings provide a mechanistic basis for DDI-predictions concerning ethambutol. According to international guidelines, anin vivointeraction study is warranted for the observedin vitrointeraction between ethambutol and moxifloxacin.

Tropane alkaloids as substrates and inhibitors of human organic cation transporters of the SLC22 (OCT) and the SLC47 (MATE) families

2017 ◽  
Vol 398 (2) ◽  
pp. 237-249 ◽  
Author(s):  
Jiayin Chen ◽  
Jürgen Brockmöller ◽  
Tina Seitz ◽  
Jörg König ◽  
Mladen V. Tzvetkov ◽  
...  
Keyword(s):  
Therapeutic Range ◽  
Organic Cation ◽  
Tropane Alkaloids ◽  
Hek293 Cells ◽  
Renal Elimination ◽  
Anticholinergic Drugs ◽  
Organic Cation Transporters ◽  
Quaternary Amine ◽  
Narrow Therapeutic Range ◽  
Cation Transporters

Abstract Tropane alkaloids and their derivatives are anticholinergic drugs with narrow therapeutic range. Here we characterize the organic cation transporters from the SLC22 (OCT1, OCT2, and OCT3) and the SLC47 families (MATE1 and MATE2-K) as potential mediators of the renal and extra-renal excretion, the two major roads of elimination of these substances. All analyzed compounds inhibited and the quaternary amine derivatives ipratropium and trospium were strongly transported by OCTs and MATEs. Overexpression of OCTs or MATEs in HEK293 cells resulted in an up to 63-fold increase in the uptake of ipratropium (Km of 0.32 μm to OCT2 and Vmax of 3.34 nmol×mg protein−1×min−1 to MATE1). The transcellular transport of ipratropium was 16-fold higher in OCT2-MATE1 and 10-fold higher in OCT1-MATE1 overexpressing compared to control MDCKII cells. Genetic polymorphisms in OCT1 and OCT2 affected ipratropium uptake and clinically relevant concentration of ondansetron and pyrithiamine inhibited ipratropium uptake via MATEs by more than 90%. This study suggests that OCT1, OCT2 and MATEs may be strongly involved in the renal and extra-renal elimination of ipratropium and other quaternary amine alkaloids. These substances have a notoriously narrow therapeutic range and the drug-drug interactions suggested here should be further critically evaluated in humans.

Transport of Dicationic Drugs Pentamidine and Furamidine by Human Organic Cation Transporters

2008 ◽  
Vol 37 (2) ◽  
pp. 424-430 ◽  
Author(s):  
Xin Ming ◽  
Wujian Ju ◽  
Huali Wu ◽  
Richard R. Tidwell ◽  
James E. Hall ◽  
...  
Keyword(s):  
Organic Cation ◽  
Organic Cation Transporters ◽  
Cation Transporters
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