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Chen Y, Zelnick LR, Wang K, Katz R, Hoofnagle AN, Becker JO, Hsu CY, Go AS, Feldman HI, Mehta RC, Lash JP, Waikar SS, Hamm L, Chen J, Shafi T, Kestenbaum BR. Association of tubular solute clearances with the glomerular filtration rate and complications of chronic kidney disease: the Chronic Renal Insufficiency Cohort study. Nephrol Dial Transplant 2020; 36:gfaa057. [PMID: 33330914 PMCID: PMC8237987 DOI: 10.1093/ndt/gfaa057] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Accepted: 02/25/2020] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND The secretion of organic solutes by the proximal tubules is an essential intrinsic kidney function. The degree to which secretory solute clearance corresponds with the glomerular filtration rate (GFR) and potential metabolic implications of net secretory clearance are largely unknown. METHODS We evaluated 1240 participants with chronic kidney disease (CKD) from the multicenter Chronic Renal Insufficiency Cohort (CRIC) Study. We used targeted mass-spectrometry to quantify candidate secretory solutes in paired 24-h urine and plasma samples. CRIC study personnel measured GFR using 125I-iothalamate clearance (iGFR). We used correlation and linear regression to determine cross-sectional associations of secretory clearances with iGFR and common metabolic complications of CKD. RESULTS Correlations between iGFR and secretory solute clearances ranged from ρ = +0.30 for hippurate to ρ = +0.58 for kynurenic acid. Lower net clearances of most secretory solutes were associated with higher serum concentrations of parathyroid hormone (PTH), triglycerides and uric acid. Each 50% lower kynurenic acid clearance was associated with a 21% higher serum PTH concentration [95% confidence interval (CI) 15-26%] and a 10% higher serum triglyceride concentration (95% CI 5-16%) after adjustment for iGFR, albuminuria and other potential confounders. Secretory solute clearances were not associated with statistically or clinically meaningful differences in serum calcium, phosphate, hemoglobin or bicarbonate concentrations. CONCLUSIONS Tubular secretory clearances are modestly correlated with measured GFR among adult patients with CKD. Lower net secretory clearances are associated with selected metabolic complications independent of GFR and albuminuria, suggesting potential clinical and biological relevance.
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Affiliation(s)
- Yan Chen
- Department of Epidemiology, University of Washington, Seattle, WA, USA
- Kidney Research Institute, Seattle, WA, USA
| | - Leila R Zelnick
- Kidney Research Institute, Seattle, WA, USA
- Department of Medicine, Division of Nephrology, University of Washington, Seattle, WA, USA
| | - Ke Wang
- Kidney Research Institute, Seattle, WA, USA
- Department of Medicine, Division of Nephrology, University of Washington, Seattle, WA, USA
| | - Ronit Katz
- Kidney Research Institute, Seattle, WA, USA
- Department of Medicine, Division of Nephrology, University of Washington, Seattle, WA, USA
| | - Andrew N Hoofnagle
- Kidney Research Institute, Seattle, WA, USA
- Department of Laboratory Medicine, University of Washington, Seattle, WA, USA
| | - Jessica O Becker
- Department of Laboratory Medicine, University of Washington, Seattle, WA, USA
| | - Chi-Yuan Hsu
- Department of Medicine, Division of Nephrology, University of California San Francisco, San Francisco, CA, USA
| | - Alan S Go
- Division of Research, Kaiser Permanente Northern California, Oakland, CA, USA
| | - Harold I Feldman
- Department of Biostatistics, Epidemiology and Informatics, University of Pennsylvania, Philadelphia, PA, USA
- Center for Clinical Epidemiology and Biostatistics, University of Pennsylvania, Philadelphia, PA, USA
| | - Rupal C Mehta
- Department of Medicine, Division of Nephrology and Hypertension, Jesse Brown Veterans Administration Medical Center & Northwestern University, Chicago, IL, USA
| | - James P Lash
- Department of Medicine, Division of Nephrology, University of Illinois at Chicago, Chicago, IL, USA
| | | | - L Hamm
- Division of Nephrology and Hypertension, Tulane University Department of Medicine, New Orleans, LA, USA
| | - Jing Chen
- Division of Nephrology and Hypertension, Tulane University Department of Medicine, New Orleans, LA, USA
| | - Tariq Shafi
- Department of Medicine, Division of Nephrology, University of Mississippi Medical Center, Jackson, MS, USA
| | - Bryan R Kestenbaum
- Kidney Research Institute, Seattle, WA, USA
- Department of Medicine, Division of Nephrology, University of Washington, Seattle, WA, USA
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Usabiaga I, Camiruaga A, Calabrese C, Veloso A, D'mello VC, Wategaonkar S, Fernández JA. Exploration of the theobromine-water dimer: comparison with DNA microhydration. Phys Chem Chem Phys 2020; 22:15759-15768. [PMID: 32627788 DOI: 10.1039/d0cp02397c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Understanding the molecular basis of the appearance of life on Earth is an exciting research field. Many factors may have influenced the election of the molecules used by living beings and evolution may have modified those original compounds. In an attempt to understand the role played by intermolecular interactions in the election of CGAT as the alphabet of life, we present here a thorough experimental and computational study on the interaction of theobromine with water. Theobromine is a xanthine derivative, structurally related to the nucleobases, and also present in many living beings. The experimental results demonstrate that the most stable isomer of theobromine-water was formed and detected in supersonic expansions. This isomer very well resembles the structure of the dimers between nucleobases and water, offering similar values of binding energy. A comparison between the results obtained for theobromine-water with those reported in the literature for monohydrates of nucleobases is also offered.
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Affiliation(s)
- Imanol Usabiaga
- Departamento de Química Física, Facultad de Ciencia y Tecnología, Universidad del País Vasco (UPV/EHU), 48940, Leioa, Spain.
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Mihaila SM, Faria J, Stefens MFJ, Stamatialis D, Verhaar MC, Gerritsen KGF, Masereeuw R. Drugs Commonly Applied to Kidney Patients May Compromise Renal Tubular Uremic Toxins Excretion. Toxins (Basel) 2020; 12:toxins12060391. [PMID: 32545617 PMCID: PMC7354492 DOI: 10.3390/toxins12060391] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2020] [Revised: 06/05/2020] [Accepted: 06/09/2020] [Indexed: 02/07/2023] Open
Abstract
In chronic kidney disease (CKD), the secretion of uremic toxins is compromised leading to their accumulation in blood, which contributes to uremic complications, in particular cardiovascular disease. Organic anion transporters (OATs) are involved in the tubular secretion of protein-bound uremic toxins (PBUTs). However, OATs also handle a wide range of drugs, including those used for treatment of cardiovascular complications and their interaction with PBUTs is unknown. The aim of this study was to investigate the interaction between commonly prescribed drugs in CKD and endogenous PBUTs with respect to OAT1-mediated uptake. We exposed a unique conditionally immortalized proximal tubule cell line (ciPTEC) equipped with OAT1 to a panel of selected drugs, including angiotensin-converting enzyme inhibitors (ACEIs: captopril, enalaprilate, lisinopril), angiotensin receptor blockers (ARBs: losartan and valsartan), furosemide and statins (pravastatin and simvastatin), and evaluated the drug-interactions using an OAT1-mediated fluorescein assay. We show that selected ARBs and furosemide significantly reduced fluorescein uptake, with the highest potency for ARBs. This was exaggerated in presence of some PBUTs. Selected ACEIs and statins had either no or a slight effect at supratherapeutic concentrations on OAT1-mediated fluorescein uptake. In conclusion, we demonstrate that PBUTs may compete with co-administrated drugs commonly used in CKD management for renal OAT1 mediated secretion, thus potentially compromising the residual renal function.
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Affiliation(s)
- Silvia M. Mihaila
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, 3854 CG Utrecht, The Netherlands; (S.M.M.); (M.C.V.); (K.G.F.G.)
- Department of Nephrology and Hypertension, University Medical Center Utrecht, 3582 CX Utrecht, The Netherlands; (J.F.); (M.F.J.S.)
| | - João Faria
- Department of Nephrology and Hypertension, University Medical Center Utrecht, 3582 CX Utrecht, The Netherlands; (J.F.); (M.F.J.S.)
| | - Maurice F. J. Stefens
- Department of Nephrology and Hypertension, University Medical Center Utrecht, 3582 CX Utrecht, The Netherlands; (J.F.); (M.F.J.S.)
| | - Dimitrios Stamatialis
- (Bio)artificial Organs, Department of Biomaterials Science and Technology, University of Twente, 7522 LW Enschede, The Netherlands;
| | - Marianne C. Verhaar
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, 3854 CG Utrecht, The Netherlands; (S.M.M.); (M.C.V.); (K.G.F.G.)
| | - Karin G. F. Gerritsen
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, 3854 CG Utrecht, The Netherlands; (S.M.M.); (M.C.V.); (K.G.F.G.)
| | - Rosalinde Masereeuw
- Department of Nephrology and Hypertension, University Medical Center Utrecht, 3582 CX Utrecht, The Netherlands; (J.F.); (M.F.J.S.)
- Correspondence:
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Chen Y, Zelnick LR, Wang K, Hoofnagle AN, Becker JO, Hsu CY, Feldman HI, Mehta RC, Lash JP, Waikar SS, Shafi T, Seliger SL, Shlipak MG, Rahman M, Kestenbaum BR. Kidney Clearance of Secretory Solutes Is Associated with Progression of CKD: The CRIC Study. J Am Soc Nephrol 2020; 31:817-827. [PMID: 32205410 PMCID: PMC7191931 DOI: 10.1681/asn.2019080811] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Accepted: 01/02/2020] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND The secretion of organic solutes by the proximal tubules is an essential intrinsic kidney function. However, the clinical significance of the kidney's clearance of tubular secretory solutes is uncertain. METHODS In this prospective cohort study, we evaluated 3416 participants with CKD from the Chronic Renal Insufficiency Cohort (CRIC) study. We measured plasma and 24-hour urine concentrations of endogenous candidate secretory solutes at baseline, using targeted liquid chromatography-tandem mass spectrometry. The study defined CKD progression by a ≥50% decline in the eGFR, initiation of maintenance dialysis, or kidney transplantation. We used Cox proportional hazards regression to test associations of secretory-solute clearances with CKD progression and mortality, adjusting for eGFR, albuminuria, and other confounding characteristics. RESULTS Participants in this ancillary study had a mean age of 58 years and 41% were black; the median eGFR was 43 ml/min per 1.73 m2. After adjustment, lower kidney clearances of six solutes-kynurenic acid, pyridoxic acid, indoxyl sulfate, xanthosine, isovalerylglycine, and cinnamoylglycine-were associated with significantly greater risks of CKD progression, with clearance of kynurenic acid, a highly protein-bound solute, having the strongest association. Lower clearances of isovalerylglycine, tiglylglycine, hippurate, and trimethyluric acid were significantly associated with all-cause mortality after adjustment. CONCLUSIONS We found lower kidney clearances of endogenous secretory solutes to be associated with CKD progression and all-cause mortality, independent of eGFR and albuminuria. This suggests that tubular clearance of secretory solutes provides additional information about kidney health beyond measurements of glomerular function alone.
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Affiliation(s)
- Yan Chen
- Department of Epidemiology, University of Washington, Seattle, Washington
- Kidney Research Institute, Seattle, Washington
| | - Leila R Zelnick
- Kidney Research Institute, Seattle, Washington
- Division of Nephrology, Department of Medicine, University of Washington, Seattle, Washington
| | - Ke Wang
- Kidney Research Institute, Seattle, Washington
- Division of Nephrology, Department of Medicine, University of Washington, Seattle, Washington
| | - Andrew N Hoofnagle
- Kidney Research Institute, Seattle, Washington
- Department of Laboratory Medicine, University of Washington, Seattle, Washington
| | - Jessica O Becker
- Department of Laboratory Medicine, University of Washington, Seattle, Washington
| | - Chi-Yuan Hsu
- Division of Nephrology, Department of Medicine, University of California San Francisco, San Francisco, California
| | - Harold I Feldman
- Department of Biostatistics, Epidemiology and Informatics, University of Pennsylvania, Philadelphia, Pennsylvania
- Center for Clinical Epidemiology and Biostatistics, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Rupal C Mehta
- Division of Nephrology and Hypertension, Department of Medicine, Jesse Brown Veterans Administration Medical Center and Northwestern University, Chicago, Illinois
| | - James P Lash
- Division of Nephrology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Sushrut S Waikar
- Brigham and Women's Hospital, Renal Division, Boston, Massachusetts
| | - Tariq Shafi
- Division of Nephrology, Department of Medicine, University of Mississippi Medical Center, Jackson, Mississippi
| | - Stephen L Seliger
- Division of Nephrology, School of Medicine, University of Maryland, Baltimore, Maryland
| | - Michael G Shlipak
- Division of Nephrology, Department of Medicine, San Francisco Veterans Affairs Medical Center, San Francisco, California
| | - Mahboob Rahman
- Division of Nephrology and Hypertension, Department of Medicine, Case Western Reserve University, Cleveland, Ohio; and
- Louis Stokes Cleveland Veterans Affairs Medical Center, University Hospitals Cleveland Medical Center, Cleveland, Ohio
| | - Bryan R Kestenbaum
- Kidney Research Institute, Seattle, Washington;
- Division of Nephrology, Department of Medicine, University of Washington, Seattle, Washington
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Monteiro J, Alves MG, Oliveira PF, Silva BM. Pharmacological potential of methylxanthines: Retrospective analysis and future expectations. Crit Rev Food Sci Nutr 2018; 59:2597-2625. [PMID: 29624433 DOI: 10.1080/10408398.2018.1461607] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Methylated xanthines (methylxanthines) are available from a significant number of different botanical species. They are ordinarily included in daily diet, in many extremely common beverages and foods. Caffeine, theophylline and theobromine are the main methylxanthines available from natural sources. The supposedly relatively low toxicity of methylxanthines, combined with the many beneficial effects that have been attributed to these compounds through time, generated a justified attention and a very prolific ground for dedicated scientific reports. Methylxanthines have been widely used as therapeutical tools, in an intriguing range of medicinal scopes. In fact, methylxanthines have been/were medically used as Central Nervous System stimulants, bronchodilators, coronary dilators, diuretics and anti-cancer adjuvant treatments. Other than these applications, methylxanthines have also been hinted to hold other beneficial health effects, namely regarding neurodegenerative diseases, cardioprotection, diabetes and fertility. However, it seems now consensual that toxicity concerns related to methylxanthine consumption and/or therapeutic use should not be dismissed. Taking all the knowledge and expectations on the potential of methylxanthines into account, we propose a systematic look at the past and future of methylxanthine pharmacologic applications, discussing all the promise and anticipating possible constraints. Anyways, methylxanthines will still substantiate considerable meaningful research and discussion for years to come.
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Affiliation(s)
- João Monteiro
- Mass Spectrometry Centre, Department of Chemistry & CESAM, University of Aveiro, Campus Universitário de Santiago , Aveiro , Portugal
| | - Marco G Alves
- Department of Microscopy, Laboratory of Cell Biology, Unit for Multidisciplinary Research in Biomedicine (UMIB), Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto , Porto , Portugal
| | - Pedro F Oliveira
- Department of Microscopy, Laboratory of Cell Biology, Unit for Multidisciplinary Research in Biomedicine (UMIB), Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto , Porto , Portugal.,Institute of Health Research an Innovation (i3S), University of Porto , Porto , Portugal
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6
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Abstract
Transporters in proximal renal tubules contribute to the disposition of numerous drugs. Furthermore, the molecular mechanisms of tubular secretion have been progressively elucidated during the past decades. Organic anions tend to be secreted by the transport proteins OAT1, OAT3 and OATP4C1 on the basolateral side of tubular cells, and multidrug resistance protein (MRP) 2, MRP4, OATP1A2 and breast cancer resistance protein (BCRP) on the apical side. Organic cations are secreted by organic cation transporter (OCT) 2 on the basolateral side, and multidrug and toxic compound extrusion (MATE) proteins MATE1, MATE2/2-K, P-glycoprotein, organic cation and carnitine transporter (OCTN) 1 and OCTN2 on the apical side. Significant drug-drug interactions (DDIs) may affect any of these transporters, altering the clearance and, consequently, the efficacy and/or toxicity of substrate drugs. Interactions at the level of basolateral transporters typically decrease the clearance of the victim drug, causing higher systemic exposure. Interactions at the apical level can also lower drug clearance, but may be associated with higher renal toxicity, due to intracellular accumulation. Whereas the importance of glomerular filtration in drug disposition is largely appreciated among clinicians, DDIs involving renal transporters are less well recognized. This review summarizes current knowledge on the roles, quantitative importance and clinical relevance of these transporters in drug therapy. It proposes an approach based on substrate-inhibitor associations for predicting potential tubular-based DDIs and preventing their adverse consequences. We provide a comprehensive list of known drug interactions with renally-expressed transporters. While many of these interactions have limited clinical consequences, some involving high-risk drugs (e.g. methotrexate) definitely deserve the attention of prescribers.
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Affiliation(s)
- Anton Ivanyuk
- Division of Clinical Pharmacology, Lausanne University Hospital (CHUV), Bugnon 17, 1011, Lausanne, Switzerland.
| | - Françoise Livio
- Division of Clinical Pharmacology, Lausanne University Hospital (CHUV), Bugnon 17, 1011, Lausanne, Switzerland
| | - Jérôme Biollaz
- Division of Clinical Pharmacology, Lausanne University Hospital (CHUV), Bugnon 17, 1011, Lausanne, Switzerland
| | - Thierry Buclin
- Division of Clinical Pharmacology, Lausanne University Hospital (CHUV), Bugnon 17, 1011, Lausanne, Switzerland
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7
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Feng Y, Wang C, Liu Q, Meng Q, Huo X, Liu Z, Sun P, Yang X, Sun H, Qin J, Liu K. Bezafibrate–mizoribine interaction: Involvement of organic anion transporters OAT1 and OAT3 in rats. Eur J Pharm Sci 2016; 81:119-28. [DOI: 10.1016/j.ejps.2015.10.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Revised: 09/19/2015] [Accepted: 10/10/2015] [Indexed: 01/11/2023]
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8
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Kell DB. The transporter-mediated cellular uptake of pharmaceutical drugs is based on their metabolite-likeness and not on their bulk biophysical properties: Towards a systems pharmacology. ACTA ACUST UNITED AC 2015. [DOI: 10.1016/j.pisc.2015.06.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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9
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Khaokhajorn P, Samipak S, Nithithanasilp S, Tanticharoen M, Amnuaykanjanasin A. Production and secretion of naphthoquinones is mediated by the MFS transporter MFS1 in the entomopathogenic fungus Ophiocordyceps sp. BCC1869. World J Microbiol Biotechnol 2015; 31:1543-54. [DOI: 10.1007/s11274-015-1903-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Accepted: 07/14/2015] [Indexed: 11/30/2022]
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10
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DuBois B, Louey S, Giraud GD, Cherala G, Jonker SS. Theophylline Pharmacokinetics in Foetal Sheep: Maternal Metabolic Capacity is the Principal Driver. Basic Clin Pharmacol Toxicol 2015; 117:226-33. [PMID: 25728792 DOI: 10.1111/bcpt.12395] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Accepted: 02/20/2015] [Indexed: 11/29/2022]
Abstract
Understanding theophylline pharmacokinetics (PK) in the foetus is essential to prevent in utero toxicity and optimize prophylactic therapies. Previous studies in pregnancy have been obfuscated by maternal dosing and inadequate sampling in the foetus; both render modelling of foetal PK difficult. Six ewes carrying singleton foetuses received theophylline (60 mg) into the foetal jugular vein. Blood samples were drawn from the foetus and ewe over 36 hr. Serum concentrations were measured. Maternal and foetal pharmacokinetic parameters were estimated. Foetal non-compartmental pharmacokinetic parameters were as follows: half-life 7.37 ± 1.22 hr; volume of distribution 44.62 ± 11.45 L; area under the curve 14.82 ± 2.71 hr/(μg/mL); and clearance 4.15 ± 0.70 L/hr. Rapid theophylline distribution across the placenta was observed. Maternal non-compartmental pharmacokinetic parameters were as follows: half-life 6.54 ± 2.44 hr; volume of distribution 32.48 ± 9.99 L; area under the curve 16.28 ± 4.53 hr/(μg/mL); and clearance 3.69 ± 1.47 L/hr. Foetal and ewe serum concentration-time profiles were fit together into a 3-compartment population pharmacokinetic model, and parameters were as follows: central volume 1.38 ± 0.11 L; 2nd peripheral compartment volume 3.11 ± 0.29 L; 3rd peripheral compartment volume 60.14 ± 6.02 L; elimination clearance 9.89 ± 0.90 L/hr; distribution clearance between central and 2nd compartment 30.87 ± 2.31 L/hr; and distribution clearance between 2nd and 3rd compartments 13.89 ± 1.11 L/hr. Cytochrome P4501A expression was robust in maternal liver; negligible activities were observed in placenta, foetal liver and foetal kidney. In vitro protein binding of theophylline was 30% lower in foetal serum compared to maternal serum (29.7 ± 4.4 versus 42.0 ± 3.6%-bound). Free concentrations were lower in the foetus than in the ewe, suggesting active transport across placenta. In summary, foetal clearance of theophylline is attributable to rapid distribution into the maternal circulation across the placenta followed by greater maternal protein binding and metabolic activity.
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Affiliation(s)
- Barent DuBois
- Department of Pharmacy Practice, College of Pharmacy, Oregon State University, Corvallis, OR, USA.,Oregon Health & Science University, Portland, OR, USA
| | - Samantha Louey
- Knight Cardiovascular Institute, Oregon Health & Science University, Portland, OR, USA
| | - George D Giraud
- Knight Cardiovascular Institute, Oregon Health & Science University, Portland, OR, USA.,VA Portland Health Care System, Portland, OR, USA
| | - Ganesh Cherala
- Department of Pharmacy Practice, College of Pharmacy, Oregon State University, Corvallis, OR, USA.,Oregon Health & Science University, Portland, OR, USA.,Knight Cardiovascular Institute, Oregon Health & Science University, Portland, OR, USA
| | - Sonnet S Jonker
- Knight Cardiovascular Institute, Oregon Health & Science University, Portland, OR, USA
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11
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Nigam SK, Bush KT, Martovetsky G, Ahn SY, Liu HC, Richard E, Bhatnagar V, Wu W. The organic anion transporter (OAT) family: a systems biology perspective. Physiol Rev 2015; 95:83-123. [PMID: 25540139 PMCID: PMC4281586 DOI: 10.1152/physrev.00025.2013] [Citation(s) in RCA: 301] [Impact Index Per Article: 33.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The organic anion transporter (OAT) subfamily, which constitutes roughly half of the SLC22 (solute carrier 22) transporter family, has received a great deal of attention because of its role in handling of common drugs (antibiotics, antivirals, diuretics, nonsteroidal anti-inflammatory drugs), toxins (mercury, aristolochic acid), and nutrients (vitamins, flavonoids). Oats are expressed in many tissues, including kidney, liver, choroid plexus, olfactory mucosa, brain, retina, and placenta. Recent metabolomics and microarray data from Oat1 [Slc22a6, originally identified as NKT (novel kidney transporter)] and Oat3 (Slc22a8) knockouts, as well as systems biology studies, indicate that this pathway plays a central role in the metabolism and handling of gut microbiome metabolites as well as putative uremic toxins of kidney disease. Nuclear receptors and other transcription factors, such as Hnf4α and Hnf1α, appear to regulate the expression of certain Oats in conjunction with phase I and phase II drug metabolizing enzymes. Some Oats have a strong selectivity for particular signaling molecules, including cyclic nucleotides, conjugated sex steroids, odorants, uric acid, and prostaglandins and/or their metabolites. According to the "Remote Sensing and Signaling Hypothesis," which is elaborated in detail here, Oats may function in remote interorgan communication by regulating levels of signaling molecules and key metabolites in tissues and body fluids. Oats may also play a major role in interorganismal communication (via movement of small molecules across the intestine, placental barrier, into breast milk, and volatile odorants into the urine). The role of various Oat isoforms in systems physiology appears quite complex, and their ramifications are discussed in the context of remote sensing and signaling.
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Affiliation(s)
- Sanjay K Nigam
- Departments of Pediatrics, Medicine, Cellular and Molecular Medicine, Bioengineering, and Family and Preventative Medicine, University of California, San Diego, La Jolla, California
| | - Kevin T Bush
- Departments of Pediatrics, Medicine, Cellular and Molecular Medicine, Bioengineering, and Family and Preventative Medicine, University of California, San Diego, La Jolla, California
| | - Gleb Martovetsky
- Departments of Pediatrics, Medicine, Cellular and Molecular Medicine, Bioengineering, and Family and Preventative Medicine, University of California, San Diego, La Jolla, California
| | - Sun-Young Ahn
- Departments of Pediatrics, Medicine, Cellular and Molecular Medicine, Bioengineering, and Family and Preventative Medicine, University of California, San Diego, La Jolla, California
| | - Henry C Liu
- Departments of Pediatrics, Medicine, Cellular and Molecular Medicine, Bioengineering, and Family and Preventative Medicine, University of California, San Diego, La Jolla, California
| | - Erin Richard
- Departments of Pediatrics, Medicine, Cellular and Molecular Medicine, Bioengineering, and Family and Preventative Medicine, University of California, San Diego, La Jolla, California
| | - Vibha Bhatnagar
- Departments of Pediatrics, Medicine, Cellular and Molecular Medicine, Bioengineering, and Family and Preventative Medicine, University of California, San Diego, La Jolla, California
| | - Wei Wu
- Departments of Pediatrics, Medicine, Cellular and Molecular Medicine, Bioengineering, and Family and Preventative Medicine, University of California, San Diego, La Jolla, California
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12
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He W, Dou H, Li Z, Wang X, Wang L, Wang R, Chang J. Investigation of the interaction between five alkaloids and human hemoglobin by fluorescence spectroscopy and molecular modeling. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2014; 123:176-186. [PMID: 24394533 DOI: 10.1016/j.saa.2013.12.059] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2013] [Revised: 11/17/2013] [Accepted: 12/05/2013] [Indexed: 06/03/2023]
Abstract
This work studied the interaction of human hemoglobin (HHb) with aminophylline, acefylline, caffeine, theophylline and diprophylline systematically by UV-vis absorption spectroscopy and fluorescence spectroscopy in combination with molecular modeling. Five alkaloids caused the fluorescence quenching of HHb by the formation of alkaloids-HHb complex. The binding constants and thermodynamic parameters were obtained. The hydrophobic and electrostatic interactions were the predominant intermolecular forces to stabilize these complexes. Results of thermodynamic analysis and molecular modeling showed that aminophylline was the strongest quencher and diprophylline was the weakest quencher.
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Affiliation(s)
- Wu He
- College of Chemistry and Molecular Engineering, Zhengzhou University, 100 Science Avenue, Zhengzhou 450001, PR China
| | - Huanjing Dou
- College of Chemistry and Molecular Engineering, Zhengzhou University, 100 Science Avenue, Zhengzhou 450001, PR China
| | - Zhigang Li
- College of Chemistry and Molecular Engineering, Zhengzhou University, 100 Science Avenue, Zhengzhou 450001, PR China
| | - Xiaogai Wang
- College of Chemistry and Molecular Engineering, Zhengzhou University, 100 Science Avenue, Zhengzhou 450001, PR China
| | - Lvjing Wang
- College of Chemistry and Molecular Engineering, Zhengzhou University, 100 Science Avenue, Zhengzhou 450001, PR China
| | - Ruiyong Wang
- College of Chemistry and Molecular Engineering, Zhengzhou University, 100 Science Avenue, Zhengzhou 450001, PR China.
| | - Junbiao Chang
- College of Chemistry and Molecular Engineering, Zhengzhou University, 100 Science Avenue, Zhengzhou 450001, PR China.
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14
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Mandíková J, Volková M, Pávek P, Česnek M, Janeba Z, Kubíček V, Trejtnar F. Interactions with selected drug renal transporters and transporter-mediated cytotoxicity in antiviral agents from the group of acyclic nucleoside phosphonates. Toxicology 2013; 311:135-46. [PMID: 23856525 DOI: 10.1016/j.tox.2013.07.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2013] [Revised: 07/01/2013] [Accepted: 07/03/2013] [Indexed: 01/09/2023]
Abstract
Members of acyclic nucleoside phosphonates (ANPs) possess antiviral and antiproliferative activities. However, several clinically important ANPs may cause renal injury, most likely due to their active accumulation in the renal tubular cells. The goal of this study was to investigate in vitro relationships between the affinity of several structurally related potent ANPs to selected human transporters and their cytotoxicity. SLC (solute carrier family) transporters (hOAT1, hOCT2, hCNT2, hCNT3) and ABC (ATP-binding cassette) transporters (MDR1, BCRP), which are typically expressed in the kidney, were included in the study. The transport and toxic parameters of the tested compounds were compared to those of two clinically approved ANPs, adefovir and tenofovir. Transport studies with transiently transfected cells were used as the main method in the experiments. Most of the ANPs studied showed the potency to interact with hOAT1. GS-9191, a double prodrug of PMEG, displayed an affinity for hOAT1 comparable with that of adefovir and tenofovir. No significant interaction of the tested ANPs with hOCT2, hCNT2 and hCNT3 was observed. Only GS-9191 was found to be a strong inhibitor for both MDR1 and BCRP. PMEO-DAPy showed the potency to interact with MDR1. Most of the tested substances caused a significant decrease in cellular viability in the cells transfected with hOAT1. Only with the exclusion of GS-9191, a relatively lipophilic compound, did the in vitro cytotoxicity of the ANPs closely correspond to their potential to interact with hOAT1. The increased cytotoxicity of the studied ANPs found in OAT1 transfected cells was effectively reduced by OAT inhibitors probenecid and quercetin. The higher cytotoxicity of the compounds with affinity to hOAT1 proved in the inhibitory experiments evidences that ANPs are not only inhibitors but also substrates of hOAT1. Any clear relationship between the potency of ANPs to inhibit the studied efflux transporters and their cytotoxicity was not demonstrated. In conclusion, the study documented that among the studied transporters hOAT1 seems to be the decisive determinant for renal handling in most of the tested ANPs. This transporter may also play an important role in the mechanism of their potential cytotoxic effects. These facts are in good accordance with previous findings in the clinically used ANPs.
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Affiliation(s)
- Jana Mandíková
- Faculty of Pharmacy in Hradec Králové, Charles University in Prague, Heyrovského 1203, Hradec Králové 500 05, Czech Republic
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15
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Numerous protein-bound solutes are cleared by the kidney with high efficiency. Kidney Int 2013; 84:585-90. [PMID: 23636170 PMCID: PMC3758437 DOI: 10.1038/ki.2013.154] [Citation(s) in RCA: 101] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2012] [Revised: 02/18/2013] [Accepted: 02/21/2013] [Indexed: 11/21/2022]
Abstract
The kidney clears numerous solutes from the plasma; however, retention of these solutes
causes uremic illness when the kidneys fail. We know remarkably little about which retained solutes
are toxic and this limits our ability to improve dialysis therapies. To explore this we employed
untargeted mass spectrometry to identify solutes that are efficiently cleared by the kidney. High
resolution mass spectrometry detected 1808 features in the urine and plasma ultrafiltrate of 5
individuals with normal renal function. The estimated clearance rates of 1082 peaks were greater
than the creatinine clearance indicating tubular secretion. Further analysis identified 90 features
representing solutes with estimated clearance rates greater than the renal plasma flow. Quantitative
mass spectrometry with stable isotope dilution confirmed that efficient clearance of these solutes
is made possible by the combination of binding to plasma proteins and tubular secretion. Tandem mass
spectrometry established the chemical identity of 13 solutes including hippuric acid, indoxyl
sulfate, and p-cresol sulfate. These 13 efficiently cleared solutes were found to accumulate in the
plasma of hemodialysis patients, with free levels rising to more than 20-fold normal for all but two
of them. Thus, further analysis of solutes efficiently cleared by secretion in the native kidney may
provide a potential route to the identification of uremic toxins.
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16
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Wang R, Xie Y, Zhang Y, Kang X, Wang X, Ge B, Chang J. Comparative study of the binding of pepsin to four alkaloids by spectrofluorimetry. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2013; 108:62-74. [PMID: 23454846 DOI: 10.1016/j.saa.2013.01.077] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2013] [Revised: 01/27/2013] [Accepted: 01/31/2013] [Indexed: 06/01/2023]
Abstract
The interactions between pepsin and four alkaloids, including caffeine (Caf), aminophylline (Ami), acefylline (Ace), diprophylline (Dip), were investigated by fluorescence, UV-visible absorption, resonance light scattering, synchronous fluorescence spectroscopy and 3D spectroscopy under mimic physiological conditions. The results revealed that Caf (Ami/Ace/Dip) caused the fluorescence quenching of pepsin by the formation of Caf (Ami/Ace/Dip)-pepsin complex. The binding constants and thermodynamic parameters at three different temperatures, the binding locality and the binding power were obtained. The hydrophobic and electrostatic interactions were the predominant intermolecular forces to stabilize the complex. Results showed that aminophylline was the stronger quencher and bound to pepsin with higher affinity than other three alkaloids.
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Affiliation(s)
- Ruiyong Wang
- Department of Chemistry, Zhengzhou University, Zhengzhou 450001, China.
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17
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Burckhardt G. Drug transport by Organic Anion Transporters (OATs). Pharmacol Ther 2012; 136:106-30. [PMID: 22841915 DOI: 10.1016/j.pharmthera.2012.07.010] [Citation(s) in RCA: 243] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Accepted: 07/10/2012] [Indexed: 02/08/2023]
Abstract
Common to all so far functionally characterized Organic Anion Transporters (OATs) is their broad substrate specificity and their ability to exchange extracellular against intracellular organic anions. Many OATs occur in renal proximal tubules, the site of active drug secretion. Exceptions are murine Oat6 (nasal epithelium), human OAT7 (liver), and rat Oat8 (renal collecting ducts). In human kidneys, OAT1, OAT2, and OAT3 are localized in the basolateral membrane, and OAT4, OAT10, and URAT1 in the apical cell membrane of proximal tubule cells, respectively. In rats and mice, Oat1 and Oat3 are located basolaterally, and Oat2, Oat5, Oat9, Oat10, and Urat1 apically. Several classes of drugs interact with human OAT1-3, including ACE inhibitors, angiotensin II receptor antagonists, diuretics, HMG CoA reductase inhibitors, β-lactam antibiotics, antineoplastic and antiviral drugs, and uricosuric drugs. For most drugs, interaction was demonstrated in vitro by inhibition of OAT-mediated transport of model substrates; for some drugs, transport by OATs was directly proven. Based on IC₅₀ values reported in the literature, OAT1 and OAT3 show comparable affinities for diuretics, cephalosporins, and nonsteroidal anti-inflammatory drugs whereas OAT2 has a lower affinity to most of these compounds. Drug-drug interactions at OAT1 and OAT3 may retard renal drug secretion and cause untoward effects. OAT4, OAT10, and URAT1 in the apical membrane contribute to proximal tubular urate absorption, and OAT10 to nicotinate absorption. OAT4 is in addition able to release drugs, e.g. diuretics, into the tubule lumen.
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Affiliation(s)
- Gerhard Burckhardt
- Abteilung Vegetative Physiologie und Pathophysiologie, Zentrum Physiologie und Pathophysiologie, Universitätsmedizin Göttingen, Humboldtallee 23, 37073 Göttingen, Germany.
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18
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19
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Emami Riedmaier A, Nies AT, Schaeffeler E, Schwab M. Organic Anion Transporters and Their Implications in Pharmacotherapy. Pharmacol Rev 2012; 64:421-49. [DOI: 10.1124/pr.111.004614] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
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20
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Burckhardt G, Burckhardt BC. In vitro and in vivo evidence of the importance of organic anion transporters (OATs) in drug therapy. Handb Exp Pharmacol 2011:29-104. [PMID: 21103968 DOI: 10.1007/978-3-642-14541-4_2] [Citation(s) in RCA: 136] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Organic anion transporters 1-10 (OAT1-10) and the urate transporter 1 (URAT1) belong to the SLC22A gene family and accept a huge variety of chemically unrelated endogenous and exogenous organic anions including many frequently described drugs. OAT1 and OAT3 are located in the basolateral membrane of renal proximal tubule cells and are responsible for drug uptake from the blood into the cells. OAT4 in the apical membrane of human proximal tubule cells is related to drug exit into the lumen and to uptake of estrone sulfate and urate from the lumen into the cell. URAT1 is the major urate-absorbing transporter in the apical membrane and is a target for uricosuric drugs. OAT10, also located in the luminal membrane, transports nicotinate with high affinity and interacts with drugs. Major extrarenal locations of OATs include the blood-brain barrier for OAT3, the placenta for OAT4, the nasal epithelium for OAT6, and the liver for OAT2 and OAT7. For all transporters we provide information on cloning, tissue distribution, factors influencing OAT abundance, interaction with endogenous compounds and different drug classes, drug/drug interactions and, if known, single nucleotide polymorphisms.
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Affiliation(s)
- Gerhard Burckhardt
- Abteilung Vegetative Physiologie und Pathophysiologie, Zentrum Physiologie und Pathophysiologie, Göttingen, Germany.
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21
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VanWert AL, Gionfriddo MR, Sweet DH. Organic anion transporters: discovery, pharmacology, regulation and roles in pathophysiology. Biopharm Drug Dispos 2010; 31:1-71. [PMID: 19953504 DOI: 10.1002/bdd.693] [Citation(s) in RCA: 113] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Our understanding of the mechanisms behind inter- and intra-patient variability in drug response is inadequate. Advances in the cytochrome P450 drug metabolizing enzyme field have been remarkable, but those in the drug transporter field have trailed behind. Currently, however, interest in carrier-mediated disposition of pharmacotherapeutics is on a substantial uprise. This is exemplified by the 2006 FDA guidance statement directed to the pharmaceutical industry. The guidance recommended that industry ascertain whether novel drug entities interact with transporters. This suggestion likely stems from the observation that several novel cloned transporters contribute significantly to the disposition of various approved drugs. Many drugs bear anionic functional groups, and thus interact with organic anion transporters (OATs). Collectively, these transporters are nearly ubiquitously expressed in barrier epithelia. Moreover, several reports indicate that OATs are subject to diverse forms of regulation, much like drug metabolizing enzymes and receptors. Thus, critical to furthering our understanding of patient- and condition-specific responses to pharmacotherapy is the complete characterization of OAT interactions with drugs and regulatory factors. This review provides the reader with a comprehensive account of the function and substrate profile of cloned OATs. In addition, a major focus of this review is on the regulation of OATs including the impact of transcriptional and epigenetic factors, phosphorylation, hormones and gender.
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Affiliation(s)
- Adam L VanWert
- Department of Pharmaceutical Sciences, Wilkes University, Wilkes-Barre, PA 18766, USA
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22
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Zhang HM, Tang BP, Wang YQ. The interaction of lysozyme with caffeine, theophylline and theobromine in solution. Mol Biol Rep 2009; 37:3127-36. [DOI: 10.1007/s11033-009-9891-x] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2009] [Accepted: 10/02/2009] [Indexed: 11/30/2022]
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23
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Mechanisms of renal anionic drug transport. Eur J Pharmacol 2008; 585:245-55. [DOI: 10.1016/j.ejphar.2008.02.085] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2007] [Revised: 02/08/2008] [Accepted: 02/20/2008] [Indexed: 01/11/2023]
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24
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Nadai M, Kato M, Yoshizumi H, Kimura M, Kurono S, Abe F, Saito H, Hasegawa T. Possible involvement of organic anion and cation transporters in renal excretion of xanthine derivatives, 3-methylxanthine and enprofylline. Life Sci 2007; 81:1175-82. [PMID: 17897683 DOI: 10.1016/j.lfs.2007.07.032] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2007] [Revised: 07/23/2007] [Accepted: 07/24/2007] [Indexed: 11/28/2022]
Abstract
Whether organic anion and cation transporters are involved in the renal excretion of xanthine derivatives, 3-methylxanthie and enprofylline, remains unclear. In this study, we have investigated the effects of typically predominant substrates for organic anion and cation transporters on the tubular secretion of 3-methylxanthine and enprofylline in rats. In the renal clearance experiments using typical substrates for organic anion transporters, probenecid and p-aminohippurate, probenecid (20 mg/kg), but not p-aminohippurate (100 mg/kg), significantly decreased the renal clearance and clearance ratio of 3-methylxanthine and enprofylline. The typical substrates for organic cation transport systems, tetraethylammonium (30.6 mg/kg) and cimetidine (50 or 100 mg/kg), significantly decreased the renal clearance and clearance ratio of 3-methylxanthine and enprofylline. These results suggest that the renal secretory transport of 3-methylxanthine and enprofylline are mediated by probenecid-, cimetidine- and tetraethylammonium-sensitive transport systems. Uric acid, an organic anion, significantly inhibited the renal secretion of 3-methylxanthine, but not enprofylline, suggesting that the renal tubular transport of 3-methylxanthine is also mediated via uric acid-sensitive transport system. These findings suggest the possibility that both organic anion and cation transporters are, at least, involved in the renal tubular transport of 3-methylxanthine and enprofylline in rats.
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Affiliation(s)
- Masayuki Nadai
- Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tenpaku-ku, Nagoya, 468-8503, Japan
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25
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Kuwayama K, Inoue H, Kanamori T, Tsujikawa K, Miyaguchi H, Iwata Y, Miyauchi S, Kamo N, Kishi T. Interactions between 3,4-methylenedioxymethamphetamine, methamphetamine, ketamine, and caffeine in human intestinal Caco-2 cells and in oral administration to rats. Forensic Sci Int 2007; 170:183-8. [DOI: 10.1016/j.forsciint.2007.02.034] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2006] [Revised: 02/14/2007] [Accepted: 02/15/2007] [Indexed: 11/25/2022]
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26
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Bakhiya N, Batke M, Laake J, Monien BH, Frank H, Seidel A, Engst W, Glatt H. Directing Role of Organic Anion Transporters in the Excretion of Mercapturic Acids of Alkylated Polycyclic Aromatic Hydrocarbons. Drug Metab Dispos 2007; 35:1824-31. [PMID: 17639024 DOI: 10.1124/dmd.107.016964] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Excretion of mercapturic acids of a xenobiotic is a good indicator for the formation of electrophilic intermediates. However, the route of excretion, urine or feces, is important for usage of a given mercapturic acid as a biomarker in humans. In the present study we investigated the excretion routes of 1-methylpyrenyl mercapturic acid (MPMA) and 1,8-dimethylpyrenyl mercapturic acid (DMPMA) formed from the corresponding benzylic alcohols in rats. Whereas MPMA was primarily excreted in urine (72% of the total urinary and fecal level), DMPMA clearly preferred the fecal route (88%). We then examined interactions of these mercapturic acids with renal basolateral organic anion transporters (OATs) using HEK293 cells stably expressing human OAT1 and OAT3. The uptake rates of MPMA by OAT1- and OAT3-expressing cells were 2.8- and 1.7-fold, respectively, higher than that by control cells. MPMA was a competitive inhibitor of p-aminohippurate uptake by OAT1 and estrone sulfate uptake by OAT3 with K(i) values of 14.5 microM and 1.5 microM, respectively. In contrast, DMPMA was not transported by OAT1 and only modestly transported by OAT3 (1.25-fold over control). Thus, we suspect that the substrate specificities, alone or together with other factors, played a directing role in the excretion of MPMA and DMPMA. Although the mechanistic link requires verification, our results clearly show that a minute structural difference (the presence or absence of an additional methyl group in an alkylated four-ring polycyclic hydrocarbon) can strongly affect the interaction with transporter proteins and direct the excretion route of mercapturic acids.
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Affiliation(s)
- Nadiya Bakhiya
- German Institute of Human Nutrition Potsdam-Rehbrücke, Arthur-Scheunert-Allee 114-116, 14558 Nuthetal, Germany
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27
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Rizwan AN, Burckhardt G. Organic anion transporters of the SLC22 family: biopharmaceutical, physiological, and pathological roles. Pharm Res 2007; 24:450-70. [PMID: 17245646 DOI: 10.1007/s11095-006-9181-4] [Citation(s) in RCA: 195] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2006] [Accepted: 10/19/2006] [Indexed: 02/08/2023]
Abstract
The human organic anion transporters OAT1, OAT2, OAT3, OAT4 and URAT1 belong to a family of poly-specific transporters mainly located in kidneys. Selected OATs occur also in liver, placenta, and brain. OATs interact with endogenous metabolic end products such as urate and acidic neutrotransmitter metabolites, as well as with a multitude of widely used drugs, including antibiotics, antihypertensives, antivirals, anti-inflammatory drugs, diuretics and uricosurics. Thereby, OATs play an important role in renal drug elimination and have an impact on pharmacokinetics. In this review we focus on the interaction of human OATs with drugs. We report the affinities of human OATs for drug classes and compare the putative importance of individual OATs for renal drug excretion. The role of OATs as sites of drug-drug interaction and mediators cell toxicity, their gender-dependent regulation in health and diseased states, and the possible impact of single nucleotide polymorphisms are also dealt with.
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Affiliation(s)
- Ahsan N Rizwan
- Abteilung Vegetative Physiologie und Pathophysiologie, Bereich Humanmedizin, Georg-August-Universität Göttingen, Humboldtallee 23, 37073, Göttingen, Germany
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28
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Abstract
Organic anion transporters (OATs) play an essential role in the elimination of numerous endogenous and exogenous organic anions from the body. The renal OATs contribute to the excretion of many drugs and their metabolites that are important in clinical medicine. Several families of multispecific organic anion and cation transporters, including OAT family transporters, have recently been identified by molecular cloning. The OAT family consists of six isoforms (OAT1 - 4, URAT1, and rodent Oat5) and they are all expressed in the kidney, while some are also expressed in the liver, brain, and placenta. The OAT family represents mainly the renal secretory and reabsorptive pathway for organic anions and is also involved in the distribution of organic anions in the body, drug-drug interactions, and toxicity of anionic substances such as nephrotoxic drugs and uremic toxins. In this review, current knowledge of and recent progress in the understanding of several aspects of OAT family members are discussed.
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Affiliation(s)
- Naohiko Anzai
- Department of Pharmacology and Toxicology, Kyorin University School of Medicine, Tokyo, Japan
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