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Amin SA, Nandi S, Kashaw SK, Jha T, Gayen S. A critical analysis of urea transporter B inhibitors: molecular fingerprints, pharmacophore features for the development of next-generation diuretics. Mol Divers 2022; 26:2549-2559. [PMID: 34978011 DOI: 10.1007/s11030-021-10353-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Accepted: 11/12/2021] [Indexed: 10/19/2022]
Abstract
Urea transporter is a membrane transport protein. It is involved in the transferring of urea across the cell membrane in humans. Along with urea transporter A, urea transporter B (UT-B) is also responsible for the management of urea concentration and blood pressure of human. The inhibitors of urea transporters have already generated a huge attention to be developed as alternate safe class of diuretic. Unlike conventional diuretics, these inhibitors are suitable for long-term therapy without hampering the precious electrolyte imbalance in the human body. In this study, UT-B inhibitors were analysed by using multi-chemometric modelling approaches. The possible pharmacophore features along with favourable and unfavourable sub-structural fingerprints for UT-B inhibition are extracted. This information will guide the medicinal chemist to design potent UT-B inhibitors in future.
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Affiliation(s)
- Sk Abdul Amin
- Natural Science Laboratory, Division of Medicinal and Pharmaceutical Chemistry, Department of Pharmaceutical Technology, Jadavpur University, P. O. Box 17020, Kolkata, India
| | - Sudipta Nandi
- Department of Pharmaceutical Sciences, Dr. Harisingh Gour University, Sagar, Madhya Pradesh, India
- Laboratory of Drug Design and Discovery, Department of Pharmaceutical Technology, Jadavpur University, Kolkata, India
| | - Sushil Kumar Kashaw
- Department of Pharmaceutical Sciences, Dr. Harisingh Gour University, Sagar, Madhya Pradesh, India
| | - Tarun Jha
- Natural Science Laboratory, Division of Medicinal and Pharmaceutical Chemistry, Department of Pharmaceutical Technology, Jadavpur University, P. O. Box 17020, Kolkata, India.
| | - Shovanlal Gayen
- Laboratory of Drug Design and Discovery, Department of Pharmaceutical Technology, Jadavpur University, Kolkata, India.
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Hailemariam S, Zhao S, He Y, Wang J. Urea transport and hydrolysis in the rumen: A review. ANIMAL NUTRITION (ZHONGGUO XU MU SHOU YI XUE HUI) 2021; 7:989-996. [PMID: 34738029 PMCID: PMC8529027 DOI: 10.1016/j.aninu.2021.07.002] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 07/02/2021] [Accepted: 07/08/2021] [Indexed: 11/29/2022]
Abstract
Inefficient dietary nitrogen (N) conversion to microbial proteins, and the subsequent use by ruminants, is a major research focus across different fields. Excess bacterial ammonia (NH3) produced due to degradation or hydrolyses of N containing compounds, such as urea, leads to an inefficiency in a host's ability to utilize nitrogen. Urea is a non-protein N containing compound used by ruminants as an ammonia source, obtained from feed and endogenous sources. It is hydrolyzed by ureases from rumen bacteria to produce NH3 which is used for microbial protein synthesis. However, lack of information exists regarding urea hydrolysis in ruminal bacteria, and how urea gets to hydrolysis sites. Therefore, this review describes research on sites of urea hydrolysis, urea transport routes towards these sites, the role and structure of urea transporters in rumen epithelium and bacteria, the composition of ruminal ureolytic bacteria, mechanisms behind urea hydrolysis by bacterial ureases, and factors influencing urea hydrolysis. This review explores the current knowledge on the structure and physiological role of urea transport and ureolytic bacteria, for the regulation of urea hydrolysis and recycling in ruminants. Lastly, underlying mechanisms of urea transportation in rumen bacteria and their physiological importance are currently unknown, and therefore future research should be directed to this subject.
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Affiliation(s)
- Samson Hailemariam
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
- Dilla University, College of Agriculture and Natural Resource, Dilla P. O. Box 419, Ethiopia
| | - Shengguo Zhao
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Yue He
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Jiaqi Wang
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
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3
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Nandi S, Sanyal S, Amin SA, Kashaw SK, Jha T, Gayen S. Urea transporter and its specific and nonspecific inhibitors: State of the art and pharmacological perspective. Eur J Pharmacol 2021; 911:174508. [PMID: 34536365 DOI: 10.1016/j.ejphar.2021.174508] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 09/10/2021] [Accepted: 09/14/2021] [Indexed: 01/11/2023]
Abstract
Hypertension is a major concern for a wide array of patients. The traditional drugs are commonly referred as 'water pills' and these molecules have been successful in alleviating hypertension. However, this comes at the high expense of precious electrolytes in our body. To dissipate this major adverse effect, the urea transporter inhibitors play especially important roles in maintaining the fluid balance by maintaining the concentration of urea in the inner medullary collecting duct. The purpose of this communication is to provide insights into the structural feature of these target proteins and inhibition of both urea transporter types A (UT-A) and B (UT-B) selectively and non-selectively with a special focus on the UT-A inhibitors as they are the primary target for diuresis. It was observed that a wide class of drugs such as thiourea analogues, 2,7-disubstituted fluorenones can inhibit both the protein non-selectively whereas 8-hydroxyquinoline, aminothiazolone, 1,3,5-triazine, triazolothienopyrimidine, thienoquinoline, arylthiazole, γ-sultambenzosulfonamide and 1,2,4-triazoloquinoxaline classes of compounds inhibit UT-A. The goal of this study is to highlight the important aspects that may be useful to understanding the perspectives of urea transporter inhibitors in rational drug discovery.
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Affiliation(s)
- Sudipta Nandi
- Department of Pharmaceutical Sciences, Dr. Harisingh Gour University, Sagar, MP, India
| | - Saptarshi Sanyal
- School of Pharmaceutical Technology, Adamas University, Kolkata, India; Natural Science Laboratory, Division of Medicinal and Pharmaceutical Chemistry, Department of Pharmaceutical Technology, Jadavpur University, Kolkata, India
| | - Sk Abdul Amin
- Natural Science Laboratory, Division of Medicinal and Pharmaceutical Chemistry, Department of Pharmaceutical Technology, Jadavpur University, Kolkata, India
| | - Sushil Kumar Kashaw
- Department of Pharmaceutical Sciences, Dr. Harisingh Gour University, Sagar, MP, India
| | - Tarun Jha
- Natural Science Laboratory, Division of Medicinal and Pharmaceutical Chemistry, Department of Pharmaceutical Technology, Jadavpur University, Kolkata, India.
| | - Shovanlal Gayen
- Department of Pharmaceutical Sciences, Dr. Harisingh Gour University, Sagar, MP, India; Laboratory of Drug Design and Discovery, Department of Pharmaceutical Technology, Jadavpur University, Kolkata, India.
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Zhang S, Zhao Y, Wang S, Li M, Xu Y, Ran J, Geng X, He J, Meng J, Shao G, Zhou H, Ge Z, Chen G, Li R, Yang B. Discovery of novel diarylamides as orally active diuretics targeting urea transporters. Acta Pharm Sin B 2021; 11:181-202. [PMID: 33532188 PMCID: PMC7838058 DOI: 10.1016/j.apsb.2020.06.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 05/14/2020] [Accepted: 05/26/2020] [Indexed: 12/17/2022] Open
Abstract
Urea transporters (UT) play a vital role in the mechanism of urine concentration and are recognized as novel targets for the development of salt-sparing diuretics. Thus, UT inhibitors are promising for development as novel diuretics. In the present study, a novel UT inhibitor with a diarylamide scaffold was discovered by high-throughput screening. Optimization of the inhibitor led to the identification of a promising preclinical candidate, N-[4-(acetylamino)phenyl]-5-nitrofuran-2-carboxamide (1H), with excellent in vitro UT inhibitory activity at the submicromolar level. The half maximal inhibitory concentrations of 1H against UT-B in mouse, rat, and human erythrocyte were 1.60, 0.64, and 0.13 μmol/L, respectively. Further investigation suggested that 8 μmol/L 1H more powerfully inhibited UT-A1 at a rate of 86.8% than UT-B at a rate of 73.9% in MDCK cell models. Most interestingly, we found for the first time that oral administration of 1H at a dose of 100 mg/kg showed superior diuretic effect in vivo without causing electrolyte imbalance in rats. Additionally, 1H did not exhibit apparent toxicity in vivo and in vitro, and possessed favorable pharmacokinetic characteristics. 1H shows promise as a novel diuretic to treat hyponatremia accompanied with volume expansion and may cause few side effects.
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Key Words
- AQP1, aquaporin 1
- BCRP, breast cancer resistance protein
- CCK-8, cell counting kit-8
- CMC-Na, carboxymethylcellulose sodium
- DMF, N,N-dimethylformamide
- Diuretic
- Fa, fraction absorbance
- GFR, glomerular filtration rate
- HDL-C and LDL-C, high- and low-density lipoprotein
- IC50, half maximal inhibitory concentration
- IMCD, inner medulla collecting duct
- Oral administration
- P-gp, P-glycoprotein
- PBS, phosphate buffered saline
- Papp, apparent permeability
- Structure optimization
- THF, tetrahydrofuran
- UT, urea transporter
- Urea transporter inhibitor
- r.t., room temperature
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Titko T, Perekhoda L, Drapak I, Tsapko Y. Modern trends in diuretics development. Eur J Med Chem 2020; 208:112855. [PMID: 33007663 DOI: 10.1016/j.ejmech.2020.112855] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 09/06/2020] [Accepted: 09/15/2020] [Indexed: 01/02/2023]
Abstract
Diuretics are the first-line therapy for widespread cardiovascular and non-cardiovascular diseases. Traditional diuretics are commonly prescribed for treatment in patients with hypertension, edema and heart failure, as well as with a number of kidney problems. They are diseases with high mortality, and the number of patients suffering from heart and kidney diseases is increasing year by year. The use of several classes of diuretics currently available for clinical use exhibits an overall favorable risk/benefit balance. However, they are not devoid of side effects. Hence, pharmaceutical researchers have been making efforts to develop new drugs with a better pharmacological profile. High-throughput screening, progress in protein structure analysis and modern methods of chemical modification have opened good possibilities for identification of new promising agents for preclinical and clinical testing. In this review, we provide an overview of the medicinal chemistry approaches toward the development of small molecule compounds showing diuretic activity that have been discovered over the past decade and are interesting drug candidates. We have discussed promising natriuretics/aquaretics/osmotic diuretics from such classes as: vasopressin receptor antagonists, SGLT2 inhibitors, urea transporters inhibitors, aquaporin antagonists, adenosine receptor antagonists, natriuretic peptide receptor agonists, ROMK inhibitors, WNK-SPAK inhibitors, and pendrin inhibitors.
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Affiliation(s)
- Tetiana Titko
- Department of Medicinal Chemistry, National University of Pharmacy, 53 Pushkinska Str., 61002, Kharkiv, Ukraine.
| | - Lina Perekhoda
- Department of Medicinal Chemistry, National University of Pharmacy, 53 Pushkinska Str., 61002, Kharkiv, Ukraine.
| | - Iryna Drapak
- Department of General, Bioinorganic, Physical and Colloidal Chemistry, Danylo Halytsky Lviv National Medical University, 69 Pekarska Str., 79010, Lviv, Ukraine.
| | - Yevgen Tsapko
- Department of Inorganic Chemistry, National University of Pharmacy, 53 Pushkinska Str., 61002, Kharkiv, Ukraine.
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6
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Li M, Zhao Y, Zhang S, Xu Y, Wang SY, Li BW, Ran JH, Li RT, Yang BX. A thienopyridine, CB-20, exerts diuretic activity by inhibiting urea transporters. Acta Pharmacol Sin 2020; 41:65-72. [PMID: 31213671 PMCID: PMC7468274 DOI: 10.1038/s41401-019-0245-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Accepted: 04/28/2019] [Indexed: 01/08/2023] Open
Abstract
Urea transporters (UTs) are transmembrane proteins selectively permeable to urea and play an important role in urine concentration. UT-knockout mice exhibit the urea-selective urine-concentrating defect, without affecting electrolyte balance, suggesting that UT-B inhibitors have the potential to be developed as novel diuretics. In this study, we characterized a novel compound 5-ethyl-2-methyl-3-amino-6-methylthieno[2,3-b]pyridine-2,5-dicarboxylate (CB-20) with UT inhibitory activity as novel diuretics with excellent pharmacological properties. This compound was discovered based on high-throughput virtual screening combined with the erythrocyte osmotic lysis assay. Selectivity of UT inhibitors was assayed using transwell chambers. Diuretic activity of the compound was examined in rats and mice using metabolic cages. Pharmacokinetic parameters were detected in rats using LC-MS/MS. Molecular docking was employed to predict the potential binding modes for the CB-20 with human UT-B. This compound dose-dependently inhibited UT-facilitated urea transport with IC50 values at low micromolar levels. It exhibited nearly equal inhibitory activity on both UT-A1 and UT-B. After subcutaneous administration of CB-20, the animals showed polyuria, without electrolyte imbalance and abnormal metabolism. CB-20 possessed a good absorption and rapid clearance in rat plasma. Administration of CB-20 for 5 days did not cause significant morphological abnormality in kidney or liver tissues of rats. Molecular docking showed that CB-20 was positioned near several residues in human UT-B, including Leu364, Val367, and so on. This study provides proof of evidence for the prominent diuretic activity of CB-20 by specifically inhibiting UTs. CB-20 or thienopyridine analogs may be developed as novel diuretics.
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Affiliation(s)
- Min Li
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, 100191, China
| | - Yan Zhao
- State Key Laboratory of Natural and Biomimetic Drugs, School of pharmaceutical Sciences, Peking University, Beijing, 100191, China
- College of Pharmacy, Inner Mongolia Medical University, Hohhot, 010110, China
| | - Shun Zhang
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, 100191, China
| | - Yue Xu
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, 100191, China
| | - Shu-Yuan Wang
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, 100191, China
| | - Bo-Wen Li
- State Key Laboratory of Natural and Biomimetic Drugs, School of pharmaceutical Sciences, Peking University, Beijing, 100191, China
| | - Jian-Hua Ran
- Chongqing Medical University, Chongqing, 400016, China
| | - Run-Tao Li
- State Key Laboratory of Natural and Biomimetic Drugs, School of pharmaceutical Sciences, Peking University, Beijing, 100191, China.
| | - Bao-Xue Yang
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, 100191, China.
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Pharmacokinetics, Tissue Distribution and Excretion of a Novel Diuretic (PU-48) in Rats. Pharmaceutics 2018; 10:pharmaceutics10030124. [PMID: 30096833 PMCID: PMC6160999 DOI: 10.3390/pharmaceutics10030124] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Revised: 07/21/2018] [Accepted: 07/27/2018] [Indexed: 01/02/2023] Open
Abstract
Methyl 3-amino-6-methoxythieno [2,3-b] quinoline-2-carboxylate (PU-48) is a novel diuretic urea transporter inhibitor. The aim of this study is to investigate the profile of plasma pharmacokinetics, tissue distribution, and excretion by oral dosing of PU-48 in rats. Concentrations of PU-48 within biological samples are determined using a validated high performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) method. After oral administration of PU-48 (3, 6, and 12 mg/kg, respectively) in self-nanomicroemulsifying drug delivery system (SNEDDS) formulation, the peak plasma concentrations (Cmax), and the area under the curve (AUC0⁻∞) were increased by the dose-dependent and linear manner, but the marked different of plasma half-life (t1/2) were not observed. This suggests that the pharmacokinetic profile of PU-48 prototype was first-order elimination kinetic characteristics within the oral three doses range in rat plasma. Moreover, the prototype of PU-48 was rapidly and extensively distributed into thirteen tissues, especially higher concentrations were detected in stomach, intestine, liver, kidney, and bladder. The total accumulative excretion of PU-48 in the urine, feces, and bile was less than 2%. This research is the first report on disposition via oral administration of PU-48 in rats, and it provides important information for further development of PU-48 as a diuretic drug candidate.
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Lee S, Cil O, Diez-Cecilia E, Anderson MO, Verkman AS. Nanomolar-Potency 1,2,4-Triazoloquinoxaline Inhibitors of the Kidney Urea Transporter UT-A1. J Med Chem 2018; 61:3209-3217. [PMID: 29589443 PMCID: PMC5976253 DOI: 10.1021/acs.jmedchem.8b00343] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Urea transporter A (UT-A) isoforms encoded by the Slc14a2 gene are expressed in kidney tubule epithelial cells, where they facilitate urinary concentration. UT-A1 inhibition is predicted to produce a unique salt-sparing diuretic action in edema and hyponatremia. Here we report the discovery of 1,2,4-triazoloquinoxalines and the analysis of 37 synthesized analogues. The most potent compound, 8ay, containing 1,2,4-triazolo[4,3- a]quinoxaline-substituted benzenesulfonamide linked by an aryl ether, rapidly and reversibly inhibited UT-A1 urea transport by a noncompetitive mechanism with IC50 ≈ 150 nM; the IC50 was ∼2 μM for the related urea transporter UT-B encoded by the Slc14a1 gene. Molecular modeling suggested a putative binding site on the UT-A1 cytoplasmic domain. In vitro metabolism showing quinoxaline ring oxidation prompted the synthesis of metabolically stable 7,8-difluoroquinoxaline analogue 8bl, which when administered to rats produced marked diuresis and reduced urinary osmolality. 8bl has substantially improved UT-A1 inhibition potency and metabolic stability compared with prior compounds.
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Affiliation(s)
- Sujin Lee
- Departments of Medicine and Physiology, University of California, San Francisco, California 94143-0521, United States
| | - Onur Cil
- Departments of Medicine and Physiology, University of California, San Francisco, California 94143-0521, United States
- Department of Pediatrics, Division of Nephrology, University of California, San Francisco, California 94143-0521, United States
| | - Elena Diez-Cecilia
- Department of Chemistry and Biochemistry, San Francisco State University, San Francisco, California 94132-1722, United States
| | - Marc O. Anderson
- Departments of Medicine and Physiology, University of California, San Francisco, California 94143-0521, United States
- Department of Chemistry and Biochemistry, San Francisco State University, San Francisco, California 94132-1722, United States
| | - Alan S. Verkman
- Departments of Medicine and Physiology, University of California, San Francisco, California 94143-0521, United States
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9
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Zhang ZY, Wang X, Liu D, Zhang H, Zhang Q, Lu YY, Li P, Lou YQ, Yang BX, Lu C, Lou YX, Zhang GL. Development and validation of an LC-MS/MS method for the determination of a novel thienoquinolin urea transporter inhibitor PU-48 in rat plasma and its application to a pharmacokinetic study. Biomed Chromatogr 2018; 32. [PMID: 29193233 DOI: 10.1002/bmc.4157] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Revised: 10/05/2017] [Accepted: 11/20/2017] [Indexed: 01/25/2023]
Abstract
A specific, sensitive and stable high-performance liquid chromatographic-tandem mass spectrometry (LC-MS/MS) method was developed and validated for the quantitative determination of methyl 3-amino-6-methoxythieno [2,3-b]quinoline-2-carboxylate (PU-48), a novel diuretic thienoquinolin urea transporter inhibitor in rat plasma. In this method, the chromatographic separation of PU-48 was achieved with a reversed-phase C18 column (100 × 2.1 mm, 3 μm) at 35°C. The mobile phase consisted of acetonitrile and water with 0.05% formic acid added with a gradient elution at flow rate of 0.3 mL/min. Samples were detected with the triple-quadrupole tandem mass spectrometer with multiple reaction monitoring mode via electrospray ionization source in positive mode. The retention time were 6.2 min for PU-48 and 7.2 min for megestrol acetate (internal standard, IS). The monitored ion transitions were mass-to-charge ratio (m/z) 289.1 → 229.2 for PU-48 and m/z 385.3 → 267.1 for the internal standard. The calibration curve for PU-48 was linear over the concentration range of 0.1-1000 ng/mL (r2 > 0.99), and the lower limit of quantitation was 0.1 ng/mL. The precision, accuracy and stability of the method were validated adequately. The developed and validated method was successfully applied to the pharmacokinetic study of PU-48 in rats.
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Affiliation(s)
- Zhi-Yuan Zhang
- Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, China
| | - Xin Wang
- Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, China
| | - Dan Liu
- Proteomics Laboratory, Medical and Health Analysis Center, Peking University, Beijing, China
| | - Hua Zhang
- Department of Pharmaceutics, School of Pharmaceutical Sciences, Peking University, Beijing, China
| | - Qiang Zhang
- Department of Pharmaceutics, School of Pharmaceutical Sciences, Peking University, Beijing, China
| | - Ying-Yuan Lu
- Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, China
| | - Pu Li
- Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, China
| | - Ya-Qing Lou
- Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, China
| | - Bao-Xue Yang
- Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, China
| | - Chuang Lu
- Department of Drug Metabolism and Pharmacokinetics, Biogen, Cambridge, Massachusetts, USA
| | - Ya-Xin Lou
- Proteomics Laboratory, Medical and Health Analysis Center, Peking University, Beijing, China
| | - Guo-Liang Zhang
- Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, China
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10
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Abstract
PURPOSE OF REVIEW Urea is transported by urea transporter proteins in kidney, erythrocytes, and other tissues. Mice in which different urea transporters have been knocked out have urine-concentrating defects, which has led to the development and testing of urea transporters Slc14A2 (UT-A) and Slc14A1 (UT-B) inhibitors as urearetics. This review summarizes the knowledge gained during the past year on urea transporter regulation and investigations into the clinical potential of urearetics. RECENT FINDINGS UT-A1 undergoes several posttranslational modifications that increase its function by increasing UT-A1 accumulation in the apical plasma membrane. UT-A1 is phosphorylated by protein kinase A, exchange protein activated by cyclic AMP, protein kinase Cα, and AMP-activated protein kinase, all at different serine residues. UT-A1 is also regulated by 14-3-3, which contributes to UT-A1 removal from the membrane. UT-A1 is glycosylated with various glycan moieties in animal models of diabetes mellitus. Transgenic expression of UT-A1 into UT-A1/UT-A3 knockout mice restores urine-concentrating ability. UT-B is present in descending vasa recta and urinary bladder, and is linked to bladder cancer. Inhibitors of UT-A and UT-B have been developed that result in diuresis with fewer abnormalities in serum electrolytes than conventional diuretics. SUMMARY Urea transporters play critical roles in the urine-concentrating mechanism. Urea transport inhibitors are a promising new class of diuretic agent.
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Affiliation(s)
- Janet D Klein
- Renal Division, Department of Medicine, and Department of Physiology, Emory University School of Medicine, Atlanta, Georgia, USA
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11
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Phenylphthalazines as small-molecule inhibitors of urea transporter UT-B and their binding model. Acta Pharmacol Sin 2016; 37:973-83. [PMID: 27238209 DOI: 10.1038/aps.2016.4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Accepted: 01/19/2016] [Indexed: 12/22/2022] Open
Abstract
AIM Urea transporters (UT) are a family of transmembrane proteins that specifically transport urea. UT inhibitors exert diuretic activity without affecting electrolyte balance. The purpose of this study was to discover novel UT inhibitors and determine the inhibition mechanism. METHODS The primary screening urea transporter B (UT-B) inhibitory activity was conducted in a collection of 10 000 diverse small molecules using mouse erythrocyte lysis assay. After discovering a hit with a core structure of 1-phenylamino-4-phenylphthalazin, the UT-B inhibitory activity of 160 analogs were examined with a stopped-flow light scattering assay and their structure-activity relationship (SAR) was analyzed. The inhibition mechanism was further investigated using in silico assays. RESULTS A phenylphthalazine compound PU1424, chemically named 5-(4-((4-methoxyphenyl) amino) phthalazin-1-yl)-2-methylbenzene sulfonamide, showed potent UT-B inhibition activity, inhibited human and mouse UT-B-mediated urea transport with IC50 value of 0.02 and 0.69 μmol/L, respectively, and exerted 100% UT-B inhibition at higher concentrations. The compound PU1424 did not affect membrane urea transport in mouse erythrocytes lacking UT-B. Structure-activity analysis revealed that the analogs with methoxyl group at R4 and sulfonic amide at R2 position exhibited the highest potency inhibition activity on UT-B. Furthermore, in silico assays validated that the R4 and R2 positions of the analogs bound to the UT-B binding pocket and exerted inhibition activity on UT-B. CONCLUSION The compound PU1424 is a novel inhibitor of both human and mouse UT-B with IC50 at submicromolar ranges. Its binding site is located at the So site of the UT-B structure.
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12
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Reed GD, von Morze C, Verkman AS, Koelsch BL, Chaumeil MM, Lustig M, Ronen SM, Bok RA, Sands JM, Larson PEZ, Wang ZJ, Larsen JHA, Kurhanewicz J, Vigneron DB. Imaging Renal Urea Handling in Rats at Millimeter Resolution using Hyperpolarized Magnetic Resonance Relaxometry. Tomography 2016; 2:125-135. [PMID: 27570835 PMCID: PMC4996281 DOI: 10.18383/j.tom.2016.00127] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
In vivo spin spin relaxation time (T2) heterogeneity of hyperpolarized [13C,15N2]urea in the rat kidney was investigated. Selective quenching of the vascular hyperpolarized 13C signal with a macromolecular relaxation agent revealed that a long-T2 component of the [13C,15N2]urea signal originated from the renal extravascular space, thus allowing the vascular and renal filtrate contrast agent pools of the [13C,15N2]urea to be distinguished via multi-exponential analysis. The T2 response to induced diuresis and antidiuresis was performed with two imaging agents: hyperpolarized [13C,15N2]urea and a control agent hyperpolarized bis-1,1-(hydroxymethyl)-1-13C-cyclopropane-2H8. Large T2 increases in the inner-medullar and papilla were observed with the former agent and not the latter during antidiuresis. Therefore, [13C,15N2]urea relaxometry is sensitive to two steps of the renal urea handling process: glomerular filtration and the inner-medullary urea transporter (UT)-A1 and UT-A3 mediated urea concentrating process. Simple motion correction and subspace denoising algorithms are presented to aid in the multi exponential data analysis. Furthermore, a T2-edited, ultra long echo time sequence was developed for sub-2 mm3 resolution 3D encoding of urea by exploiting relaxation differences in the vascular and filtrate pools.
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Affiliation(s)
- Galen D Reed
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA; Graduate Group in Bioengineering University of California San Francisco, San Francisco, California, USA, and University of California Berkeley, Berkeley, California, USA
| | - Cornelius von Morze
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA
| | - Alan S Verkman
- Departments of Medicine and Physiology, University of California San Francisco, San Francisco, California, USA
| | - Bertram L Koelsch
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA; Graduate Group in Bioengineering University of California San Francisco, San Francisco, California, USA, and University of California Berkeley, Berkeley, California, USA
| | - Myriam M Chaumeil
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA
| | - Michael Lustig
- Graduate Group in Bioengineering University of California San Francisco, San Francisco, California, USA, and University of California Berkeley, Berkeley, California, USA; Department of Electrical Engineering and Computer Sciences, University of California Berkeley, Berkeley, California, USA
| | - Sabrina M Ronen
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA; Graduate Group in Bioengineering University of California San Francisco, San Francisco, California, USA, and University of California Berkeley, Berkeley, California, USA
| | - Robert A Bok
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA
| | - Jeff M Sands
- Department of Medicine, Renal Division, Emory University, Atlanta, Georgia, USA
| | - Peder E Z Larson
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA; Graduate Group in Bioengineering University of California San Francisco, San Francisco, California, USA, and University of California Berkeley, Berkeley, California, USA
| | - Zhen J Wang
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA
| | - Jan Henrik Ardenkjær Larsen
- GE Healthcare, Brøndby, Denmark; Department of Electrical Engineering, Technical University of Denmark, Kongens Lyngby, Denmark
| | - John Kurhanewicz
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA; Graduate Group in Bioengineering University of California San Francisco, San Francisco, California, USA, and University of California Berkeley, Berkeley, California, USA
| | - Daniel B Vigneron
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA; Graduate Group in Bioengineering University of California San Francisco, San Francisco, California, USA, and University of California Berkeley, Berkeley, California, USA
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13
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Reed GD, von Morze C, Verkman AS, Koelsch BL, Chaumeil MM, Lustig M, Ronen SM, Bok RA, Sands JM, Larson PEZ, Wang ZJ, Larsen JHA, Kurhanewicz J, Vigneron DB. Imaging Renal Urea Handling in Rats at Millimeter Resolution using Hyperpolarized Magnetic Resonance Relaxometry. Tomography 2016. [PMID: 27570835 DOI: 10.18383/j.tom2016.00127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/24/2023] Open
Abstract
In vivo spin spin relaxation time (T2) heterogeneity of hyperpolarized [13C,15N2]urea in the rat kidney was investigated. Selective quenching of the vascular hyperpolarized 13C signal with a macromolecular relaxation agent revealed that a long-T2 component of the [13C,15N2]urea signal originated from the renal extravascular space, thus allowing the vascular and renal filtrate contrast agent pools of the [13C,15N2]urea to be distinguished via multi-exponential analysis. The T2 response to induced diuresis and antidiuresis was performed with two imaging agents: hyperpolarized [13C,15N2]urea and a control agent hyperpolarized bis-1,1-(hydroxymethyl)-1-13C-cyclopropane-2H8. Large T2 increases in the inner-medullar and papilla were observed with the former agent and not the latter during antidiuresis. Therefore, [13C,15N2]urea relaxometry is sensitive to two steps of the renal urea handling process: glomerular filtration and the inner-medullary urea transporter (UT)-A1 and UT-A3 mediated urea concentrating process. Simple motion correction and subspace denoising algorithms are presented to aid in the multi exponential data analysis. Furthermore, a T2-edited, ultra long echo time sequence was developed for sub-2 mm3 resolution 3D encoding of urea by exploiting relaxation differences in the vascular and filtrate pools.
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Affiliation(s)
- Galen D Reed
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA; Graduate Group in Bioengineering University of California San Francisco, San Francisco, California, USA, and University of California Berkeley, Berkeley, California, USA
| | - Cornelius von Morze
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA
| | - Alan S Verkman
- Departments of Medicine and Physiology, University of California San Francisco, San Francisco, California, USA
| | - Bertram L Koelsch
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA; Graduate Group in Bioengineering University of California San Francisco, San Francisco, California, USA, and University of California Berkeley, Berkeley, California, USA
| | - Myriam M Chaumeil
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA
| | - Michael Lustig
- Graduate Group in Bioengineering University of California San Francisco, San Francisco, California, USA, and University of California Berkeley, Berkeley, California, USA; Department of Electrical Engineering and Computer Sciences, University of California Berkeley, Berkeley, California, USA
| | - Sabrina M Ronen
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA; Graduate Group in Bioengineering University of California San Francisco, San Francisco, California, USA, and University of California Berkeley, Berkeley, California, USA
| | - Robert A Bok
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA
| | - Jeff M Sands
- Department of Medicine, Renal Division, Emory University, Atlanta, Georgia, USA
| | - Peder E Z Larson
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA; Graduate Group in Bioengineering University of California San Francisco, San Francisco, California, USA, and University of California Berkeley, Berkeley, California, USA
| | - Zhen J Wang
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA
| | - Jan Henrik Ardenkjær Larsen
- GE Healthcare, Brøndby, Denmark; Department of Electrical Engineering, Technical University of Denmark, Kongens Lyngby, Denmark
| | - John Kurhanewicz
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA; Graduate Group in Bioengineering University of California San Francisco, San Francisco, California, USA, and University of California Berkeley, Berkeley, California, USA
| | - Daniel B Vigneron
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA; Graduate Group in Bioengineering University of California San Francisco, San Francisco, California, USA, and University of California Berkeley, Berkeley, California, USA
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14
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Ren H, Wang Y, Xing Y, Ran J, Liu M, Lei T, Zhou H, Li R, Sands JM, Yang B. Thienoquinolins exert diuresis by strongly inhibiting UT-A urea transporters. Am J Physiol Renal Physiol 2014; 307:F1363-72. [PMID: 25298523 DOI: 10.1152/ajprenal.00421.2014] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Urea transporters (UT) play an important role in the urine concentration mechanism by mediating intrarenal urea recycling, suggesting that UT inhibitors could have therapeutic use as a novel class of diuretic. Recently, we found a thienoquinolin UT inhibitor, PU-14, that exhibited diuretic activity. The purpose of this study was to identify more potent UT inhibitors that strongly inhibit UT-A isoforms in the inner medullary collecting duct (IMCD). Efficient thienoquinolin UT inhibitors were identified by structure-activity relationship analysis. Urea transport inhibition activity was assayed in perfused rat terminal IMCDs. Diuretic activity of the compound was determined in rats and mice using metabolic cages. The results show that the compound PU-48 exhibited potent UT-A inhibition activity. The inhibition was 69.5% with an IC50 of 0.32 μM. PU-48 significantly inhibited urea transport in perfused rat terminal IMCDs. PU-48 caused significant diuresis in UT-B null mice, which indicates that UT-A is the target of PU-48. The diuresis caused by PU-48 did not change blood Na(+), K(+), or Cl(-) levels or nonurea solute excretion in rats and mice. No toxicity was detected in cells or animals treated with PU-48. The results indicate that thienoquinolin UT inhibitors induce a diuresis by inhibiting UT-A in the IMCD. This suggests that they may have the potential to be developed as a novel class of diuretics with fewer side effects than classical diuretics.
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Affiliation(s)
- Huiwen Ren
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, China
| | - Yanhua Wang
- Renal Division, Departments of Medicine and Physiology, Emory University School of Medicine, Atlanta, Georgia
| | - Yongning Xing
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, China
| | - Jianhua Ran
- Department of Anatomy, Neuroscience Research Center, Basic Medical College, Chongqing Medical University, Chongqing, China; and
| | - Ming Liu
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, China
| | - Tianluo Lei
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, China
| | - Hong Zhou
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, China
| | - Runtao Li
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, China
| | - Jeff M Sands
- Renal Division, Departments of Medicine and Physiology, Emory University School of Medicine, Atlanta, Georgia
| | - Baoxue Yang
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, China; Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Beijing, China
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15
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Esteva-Font C, Cil O, Phuan PW, Su T, Lee S, Anderson MO, Verkman AS. Diuresis and reduced urinary osmolality in rats produced by small-molecule UT-A-selective urea transport inhibitors. FASEB J 2014; 28:3878-90. [PMID: 24843071 PMCID: PMC4139901 DOI: 10.1096/fj.14-253872] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Accepted: 05/05/2014] [Indexed: 11/11/2022]
Abstract
Urea transport (UT) proteins of the UT-A class are expressed in epithelial cells in kidney tubules, where they are required for the formation of a concentrated urine by countercurrent multiplication. Here, using a recently developed high-throughput assay to identify UT-A inhibitors, a screen of 50,000 synthetic small molecules identified UT-A inhibitors of aryl-thiazole, γ-sultambenzosulfonamide, aminocarbonitrile butene, and 4-isoxazolamide chemical classes. Structure-activity analysis identified compounds that inhibited UT-A selectively by a noncompetitive mechanism with IC50 down to ∼1 μM. Molecular modeling identified putative inhibitor binding sites on rat UT-A. To test compound efficacy in rats, formulations and administration procedures were established to give therapeutic inhibitor concentrations in blood and urine. We found that intravenous administration of an indole thiazole or a γ-sultambenzosulfonamide at 20 mg/kg increased urine output by 3-5-fold and reduced urine osmolality by ∼2-fold compared to vehicle control rats, even under conditions of maximum antidiuresis produced by 1-deamino-8-D-arginine vasopressin (DDAVP). The diuresis was reversible and showed urea > salt excretion. The results provide proof of concept for the diuretic action of UT-A-selective inhibitors. UT-A inhibitors are first in their class salt-sparing diuretics with potential clinical indications in volume-overload edemas and high-vasopressin-associated hyponatremias.
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Affiliation(s)
- Cristina Esteva-Font
- Department of Medicine and Department of Physiology, University of California, San Francisco, California, USA and
| | - Onur Cil
- Department of Medicine and Department of Physiology, University of California, San Francisco, California, USA and
| | - Puay-Wah Phuan
- Department of Medicine and Department of Physiology, University of California, San Francisco, California, USA and
| | - Tao Su
- Department of Medicine and Department of Physiology, University of California, San Francisco, California, USA and
| | - Sujin Lee
- Department of Medicine and Department of Physiology, University of California, San Francisco, California, USA and
| | - Marc O Anderson
- Department of Chemistry and Biochemistry, San Francisco State University, San Francisco, California, USA
| | - A S Verkman
- Department of Medicine and Department of Physiology, University of California, San Francisco, California, USA and
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16
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Li M, Tou WI, Zhou H, Li F, Ren H, Chen CYC, Yang B. Developing hypothetical inhibition mechanism of novel urea transporter B inhibitor. Sci Rep 2014; 4:5775. [PMID: 25047372 PMCID: PMC5376056 DOI: 10.1038/srep05775] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Accepted: 06/27/2014] [Indexed: 02/03/2023] Open
Abstract
Urea transporter B (UT-B) is a membrane channel protein that specifically transports urea. UT-B null mouse exhibited urea selective urine concentrating ability deficiency, which suggests the potential clinical applications of the UT-B inhibitors as novel diuretics. Primary high-throughput virtual screening (HTVS) of 50000 small-molecular drug-like compounds identified 2319 hit compounds. These 2319 compounds were screened by high-throughput screening using an erythrocyte osmotic lysis assay. Based on the pharmacological data, putative UT-B binding sites were identified by structure-based drug design and validated by ligand-based and QSAR model. Additionally, UT-B structural and functional characteristics under inhibitors treated and untreated conditions were simulated by molecular dynamics (MD). As the result, we identified four classes of compounds with UT-B inhibitory activity and predicted a human UT-B model, based on which computative binding sites were identified and validated. A novel potential mechanism of UT-B inhibitory activity was discovered by comparing UT-B from different species. Results suggest residue PHE198 in rat and mouse UT-B might block the inhibitor migration pathway. Inhibitory mechanisms of UT-B inhibitors and the functions of key residues in UT-B were proposed. The binding site analysis provides a structural basis for lead identification and optimization of UT-B inhibitors.
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Affiliation(s)
- Min Li
- The State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, 100191, China
- These authors contributed equally to this work
| | - Weng Ieong Tou
- School of Medicine, College of Medicine, China Medical University, Taichung, 40402, Taiwan
- These authors contributed equally to this work
| | - Hong Zhou
- The State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, 100191, China
| | - Fei Li
- The State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, 100191, China
- School of Pharmaceutical Sciences, Hubei University of Medicine, Shiyan, 442000, China
| | - Huiwen Ren
- The State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, 100191, China
| | - Calvin Yu-Chian Chen
- School of Medicine, College of Medicine, China Medical University, Taichung, 40402, Taiwan
- Human Genetic Center, Department of Medical Research, China Medical University Hospital, Taichung, Taiwan
- Department of Biomedical Informatics, Asia University, Taichung, 41354, Taiwan
- Research Center for Chinese Medicine & Acupuncture, China Medical University, Taichung 40402, Taiwan
| | - Baoxue Yang
- The State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, 100191, China
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17
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Abstract
UT-A and UT-B families of urea transporters consist of multiple isoforms that are subject to regulation of both acutely and by long-term measures. This chapter provides a brief overview of the expression of the urea transporter forms and their locations in the kidney. Rapid regulation of UT-A1 results from the combination of phosphorylation and membrane accumulation. Phosphorylation of UT-A1 has been linked to vasopressin and hyperosmolality, although through different kinases. Other acute influences on urea transporter activity are ubiquitination and glycosylation, both of which influence the membrane association of the urea transporter, again through different mechanisms. Long-term regulation of urea transport is most closely associated with the environment that the kidney experiences. Low-protein diets may influence the amount of urea transporter available. Conditions of osmotic diuresis, where urea concentrations are low, will prompt an increase in urea transporter abundance. Although adrenal steroids affect urea transporter abundance, conflicting reports make conclusions tenuous. Urea transporters are upregulated when P2Y2 purinergic receptors are decreased, suggesting a role for these receptors in UT regulation. Hypercalcemia and hypokalemia both cause urine concentration deficiencies. Urea transporter abundances are reduced in aging animals and animals with angiotensin-converting enzyme deficiencies. This chapter will provide information about both rapid and long-term regulation of urea transporters and provide an introduction into the literature.
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Affiliation(s)
- Janet D Klein
- Renal Division, Department of Medicine and Department of Physiology, Emory University School of Medicine, WMB Room 3319B, 1639 Pierce Drive, NE, Atlanta, GA, 30322, USA,
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