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Chen W, Liu J, Zheng C, Bai Q, Gao Q, Zhang Y, Dong K, Lu T. Research Progress on Improving the Efficiency of CDT by Exacerbating Tumor Acidification. Int J Nanomedicine 2022; 17:2611-2628. [PMID: 35712639 PMCID: PMC9196673 DOI: 10.2147/ijn.s366187] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2022] [Accepted: 05/16/2022] [Indexed: 12/21/2022] Open
Abstract
In recent years, chemodynamic therapy (CDT) has received extensive attention as a novel means of cancer treatment. The CDT agents can exert Fenton and Fenton-like reactions in the acidic tumor microenvironment (TME), converting hydrogen peroxide (H2O2) into highly toxic hydroxyl radicals (·OH). However, the pH of TME, as an essential factor in the Fenton reaction, does not catalyze the reaction effectively, hindering its efficiency, which poses a significant challenge for the future clinical application of CDT. Therefore, this paper reviews various strategies to enhance the antitumor properties of nanomaterials by modulating tumor acidity. Ultimately, the performance of CDT can be further improved by inducing strong oxidative stress to produce sufficient ·OH. In this paper, the various acidification pathways and proton pumps with potential acidification functions are mainly discussed, such as catalytic enzymes, exogenous acids, CAIX, MCT, NHE, NBCn1, etc. The problems, opportunities, and challenges of CDT in the cancer field are also discussed, thereby providing new insights for the design of nanomaterials and laying the foundation for their future clinical applications.
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Affiliation(s)
- Wenting Chen
- Key Laboratory for Space Biosciences and Biotechnology, School of Life Sciences, Northwestern Polytechnical University, Xi'an, 710072, People's Republic of China
| | - Jinxi Liu
- Key Laboratory for Space Biosciences and Biotechnology, School of Life Sciences, Northwestern Polytechnical University, Xi'an, 710072, People's Republic of China
| | - Caiyun Zheng
- Key Laboratory for Space Biosciences and Biotechnology, School of Life Sciences, Northwestern Polytechnical University, Xi'an, 710072, People's Republic of China
| | - Que Bai
- Key Laboratory for Space Biosciences and Biotechnology, School of Life Sciences, Northwestern Polytechnical University, Xi'an, 710072, People's Republic of China
| | - Qian Gao
- Key Laboratory for Space Biosciences and Biotechnology, School of Life Sciences, Northwestern Polytechnical University, Xi'an, 710072, People's Republic of China
| | - Yanni Zhang
- Key Laboratory for Space Biosciences and Biotechnology, School of Life Sciences, Northwestern Polytechnical University, Xi'an, 710072, People's Republic of China
| | - Kai Dong
- School of Pharmacy, Xi'an Jiaotong University, Xi'an, 710072, People's Republic of China
| | - Tingli Lu
- Key Laboratory for Space Biosciences and Biotechnology, School of Life Sciences, Northwestern Polytechnical University, Xi'an, 710072, People's Republic of China
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2
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Wang SB, Liu H, Li GY, Lei K, Li XJ, Quan ZS, Wang XK. Synthesis and Evaluation of Anticonvulsant Activities of 4-Phenylpiperidin- 2-one Derivatives. LETT DRUG DES DISCOV 2020. [DOI: 10.2174/1570180816666190710142848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Background:
Although Antiepileptic Drugs (AEDs) acting on various targets have been
applied in the clinic, the efficacy and tolerance of AEDs in the treatment of epilepsy have not
significantly improved. Therefore, there is an urgent need to develop some novel chemical moieties
with a better safety profile and greater efficacy. We designed and synthesized twenty-seven 4-
phenylpiperidin-2-one derivatives. This study aimed to investigate the potential use of a series of 4-
phenylpiperidin-2-one derivatives as anticonvulsant drugs.
Methods:
Two experimental methods, Maximal Electroshock (MES) and subcutaneous
pentylenetetrazole (scPTZ), were used to evaluate the anticonvulsant activity of the target
compounds. Moreover, neurotoxicity (NT) was tested using the rotarod test.
Results:
Compound 7-[4-(trifluoromethyl)phenyl]-6,7-dihydrothieno[3,2-b]pyridin-5-(4H)-one (11;
MES, ED50 = 23.7 mg/kg, PI > 33.7; PTZ, ED50 = 78.1 mg/kg, PI > 10.0) showed the best
anticonvulsant activity. The results of in vivo γ-aminobutyric Acid (GABA) estimation showed that
compound 11 may have an effect on the GABA system. Compound 11 showed significant
interactions with residues at the benzodiazepine (BZD)-binding site on GABAA receptors. Most
target compounds have favorable blood brain barrier (BBB) permeability and oral bioavailability in
predictions using silico molecular properties.
Conclusion:
According to the in vivo and in silico studies, compound 11 stand out as potential
anticonvulsant agents for further studies.
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Affiliation(s)
- Shi-Ben Wang
- College of Pharmacy, Liaocheng University, Liaocheng, Shandong 252059, China
| | - Hui Liu
- College of life sciences, Liaocheng University, Liaocheng, Shandong 252059, China
| | - Guang-Yong Li
- College of Pharmacy, Liaocheng University, Liaocheng, Shandong 252059, China
| | - Kang Lei
- College of Pharmacy, Liaocheng University, Liaocheng, Shandong 252059, China
| | - Xiao-Jing Li
- College of Pharmacy, Liaocheng University, Liaocheng, Shandong 252059, China
| | - Zhe-Shan Quan
- College of Pharmacy, Yanbian University, Yanji, Jilin 133002, China
| | - Xue-Kun Wang
- College of Pharmacy, Liaocheng University, Liaocheng, Shandong 252059, China
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3
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Niederberger P, Farine E, Raillard M, Dornbierer M, Freed DH, Large SR, Chew HC, MacDonald PS, Messer SJ, White CW, Carrel TP, Tevaearai Stahel HT, Longnus SL. Heart Transplantation With Donation After Circulatory Death. Circ Heart Fail 2020; 12:e005517. [PMID: 30998395 DOI: 10.1161/circheartfailure.118.005517] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Heart transplantation remains the preferred option for improving quality of life and survival for patients suffering from end-stage heart failure. Unfortunately, insufficient supply of cardiac grafts has become an obstacle. Increasing organ availability with donation after circulatory death (DCD) may be a promising option to overcome the organ shortage. Unlike conventional donation after brain death, DCD organs undergo a period of warm, global ischemia between circulatory arrest and graft procurement, which raises concerns for graft quality. Nonetheless, the potential of DCD heart transplantation is being reconsidered, after reports of more than 70 cases in Australia and the United Kingdom over the past 3 years. Ensuring optimal patient outcomes and generalized adoption of DCD in heart transplantation, however, requires further development of clinical protocols, which in turn require a better understanding of cardiac ischemia-reperfusion injury and the various possibilities to limit its adverse effects. Thus, we aim to provide an overview of the knowledge obtained with preclinical studies in animal models of DCD heart transplantation, to facilitate and promote the most effective and efficient advancement in preclinical research. A literature search of the PubMed database was performed to identify all relevant preclinical studies in DCD heart transplantation. Specific aspects relevant for DCD heart transplantation were analyzed, including animal models, graft procurement and storage conditions, cardioprotective approaches, and graft evaluation strategies. Several potential therapeutic strategies for optimizing graft quality are identified, and recommendations for further preclinical research are provided.
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Affiliation(s)
- Petra Niederberger
- Department of Cardiovascular Surgery, Inselspital, Bern University Hospital and Department for BioMedical Research, University of Bern, Switzerland (P.N., E.F., M.D., T.P.C., H.T.T.S., S.L.L.)
| | - Emilie Farine
- Department of Cardiovascular Surgery, Inselspital, Bern University Hospital and Department for BioMedical Research, University of Bern, Switzerland (P.N., E.F., M.D., T.P.C., H.T.T.S., S.L.L.)
| | - Mathieu Raillard
- Experimental Surgery Unit (ESI), Experimental Surgery Unit, Department for BioMedical Research and Vetsuisse Faculty, Department of Clinical Veterinary Medicine, Institute of Anaesthesiology and Pain Therapy, University of Bern, Switzerland (M.R.)
| | - Monika Dornbierer
- Department of Cardiovascular Surgery, Inselspital, Bern University Hospital and Department for BioMedical Research, University of Bern, Switzerland (P.N., E.F., M.D., T.P.C., H.T.T.S., S.L.L.)
| | - Darren H Freed
- Cardiac Surgery, University of Alberta, Edmonton, Canada (D.H.F., C.W.W.)
| | - Stephen R Large
- Department of Transplantation, Royal Papworth Hospital, Papworth Everard, Cambridge, United Kingdom (S.R.L., S.J.M.)
| | - Hong C Chew
- St Vincent's Hospital, University of New South Wales, Victor Chang Cardiac Research Institute, Sydney, Australia (H.C.C., P.S.M.)
| | - Peter S MacDonald
- St Vincent's Hospital, University of New South Wales, Victor Chang Cardiac Research Institute, Sydney, Australia (H.C.C., P.S.M.)
| | - Simon J Messer
- Department of Transplantation, Royal Papworth Hospital, Papworth Everard, Cambridge, United Kingdom (S.R.L., S.J.M.)
| | | | - Thierry P Carrel
- Department of Cardiovascular Surgery, Inselspital, Bern University Hospital and Department for BioMedical Research, University of Bern, Switzerland (P.N., E.F., M.D., T.P.C., H.T.T.S., S.L.L.)
| | - Hendrik T Tevaearai Stahel
- Department of Cardiovascular Surgery, Inselspital, Bern University Hospital and Department for BioMedical Research, University of Bern, Switzerland (P.N., E.F., M.D., T.P.C., H.T.T.S., S.L.L.)
| | - Sarah L Longnus
- Department of Cardiovascular Surgery, Inselspital, Bern University Hospital and Department for BioMedical Research, University of Bern, Switzerland (P.N., E.F., M.D., T.P.C., H.T.T.S., S.L.L.)
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4
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Baark F, Shaughnessy F, Pell VR, Clark JE, Eykyn TR, Blower P, Southworth R. Tissue acidosis does not mediate the hypoxia selectivity of [ 64Cu][Cu(ATSM)] in the isolated perfused rat heart. Sci Rep 2019; 9:499. [PMID: 30679497 PMCID: PMC6346098 DOI: 10.1038/s41598-018-36145-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Accepted: 11/15/2018] [Indexed: 01/16/2023] Open
Abstract
Copper-64-Diacetyl-bis(N4-methylthiosemicarbazone) [64Cu][Cu(ATSM)] is a hypoxia-targeting PET tracer with applications in oncology and cardiology. Upon entering a hypoxic cell, [64Cu][Cu(II)(ATSM)] is reduced to a putative [64Cu][Cu(I)(ATSM)]- species which dissociates to deposit radiocopper, thereby providing hypoxic contrast. This process may be dependent upon protonation arising from intracellular acidosis. Since acidosis is a hallmark of ischemic tissue and tumors, the hypoxia specificity of [64Cu][Cu(ATSM)] may be confounded by changes in intracellular pH. We have therefore determined the influence of intracellular pH on [64Cu][Cu(ATSM)] pharmacokinetics. Using isolated perfused rat hearts, acidosis was induced using an ammonium pre-pulse method, with and without hypoxic buffer perfusion. Cardiac [64Cu][Cu(ATSM)] pharmacokinetics were determined using NaI detectors, with intracellular pH and cardiac energetics monitored in parallel by 31P NMR. To distinguish direct acidotic effects on tracer pharmacokinetics from acidosis-induced hypocontractility, parallel studies used lidocaine perfusion to abolish cardiac contraction. Hypoxic myocardium trapped [64Cu][Cu(ATSM)] despite no evidence of it being acidotic when characterised by 31P NMR. Independent induction of tissue acidosis had no direct effect on [64Cu][Cu(ATSM)] pharmacokinetics in either normoxic or hypoxic hearts, beyond decreasing cardiac oxygen consumption to alleviate hypoxia and decrease tracer retention, leading us to conclude that tissue acidosis does not mediate the hypoxia selectivity of [64Cu][Cu(ATSM)].
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Affiliation(s)
- Friedrich Baark
- School of Biomedical Engineering & Imaging Sciences, King's College London, London, UK
- School of Cardiovascular Medicine and Sciences, BHF Centre, King's College London, London, UK
| | - Fiona Shaughnessy
- School of Biomedical Engineering & Imaging Sciences, King's College London, London, UK
| | - Victoria R Pell
- School of Biomedical Engineering & Imaging Sciences, King's College London, London, UK
- School of Cardiovascular Medicine and Sciences, BHF Centre, King's College London, London, UK
| | - James E Clark
- School of Cardiovascular Medicine and Sciences, BHF Centre, King's College London, London, UK
| | - Thomas R Eykyn
- School of Biomedical Engineering & Imaging Sciences, King's College London, London, UK
| | - Philip Blower
- School of Biomedical Engineering & Imaging Sciences, King's College London, London, UK
| | - Richard Southworth
- School of Biomedical Engineering & Imaging Sciences, King's College London, London, UK.
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5
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White CW, Messer SJ, Large SR, Conway J, Kim DH, Kutsogiannis DJ, Nagendran J, Freed DH. Transplantation of Hearts Donated after Circulatory Death. Front Cardiovasc Med 2018; 5:8. [PMID: 29487855 PMCID: PMC5816942 DOI: 10.3389/fcvm.2018.00008] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Accepted: 01/19/2018] [Indexed: 12/17/2022] Open
Abstract
Cardiac transplantation has become limited by a critical shortage of suitable organs from brain-dead donors. Reports describing the successful clinical transplantation of hearts donated after circulatory death (DCD) have recently emerged. Hearts from DCD donors suffer significant ischemic injury prior to organ procurement; therefore, the traditional approach to the transplantation of hearts from brain-dead donors is not applicable to the DCD context. Advances in our understanding of ischemic post-conditioning have facilitated the development of DCD heart resuscitation strategies that can be used to minimize ischemia-reperfusion injury at the time of organ procurement. The availability of a clinically approved ex situ heart perfusion device now allows DCD heart preservation in a normothermic beating state and minimizes exposure to incremental cold ischemia. This technology also facilitates assessments of organ viability to be undertaken prior to transplantation, thereby minimizing the risk of primary graft dysfunction. The application of a tailored approach to DCD heart transplantation that focuses on organ resuscitation at the time of procurement, ex situ preservation, and pre-transplant assessments of organ viability has facilitated the successful clinical application of DCD heart transplantation. The transplantation of hearts from DCD donors is now a clinical reality. Investigating ways to optimize the resuscitation, preservation, evaluation, and long-term outcomes is vital to ensure a broader application of DCD heart transplantation in the future.
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Affiliation(s)
| | - Simon J Messer
- Papworth Hospital NHS Foundation Trust, Cambridge, United Kingdom
| | - Stephen R Large
- Papworth Hospital NHS Foundation Trust, Cambridge, United Kingdom
| | | | - Daniel H Kim
- Cardiology, University of Alberta, Edmonton, AB, Canada
| | | | - Jayan Nagendran
- Cardiac Surgery, University of Alberta, Edmonton, AB, Canada
| | - Darren H Freed
- Cardiac Surgery, University of Alberta, Edmonton, AB, Canada.,Department of Physiology, University of Alberta, Edmonton, AB, Canada.,Department of Biomedical Engineering, University of Alberta, Edmonton, AB, Canada
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6
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Larrazabal CS, Carretta MD, Hidalgo MA, Burgos RA. Amiloride interferes with platelet- activating factor-induced respiratory burst and MMP-9 release in bovine neutrophils independent of Na +/H + exchanger 1. Vet Immunol Immunopathol 2017; 191:68-73. [PMID: 28895869 DOI: 10.1016/j.vetimm.2017.08.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Revised: 08/10/2017] [Accepted: 08/22/2017] [Indexed: 01/15/2023]
Abstract
Cytoplasmic pH homeostasis is required for an appropriate response in polymorphonuclear neutrophils (PMNs). In these cells, chemotaxis and reactive oxygen species (ROS) production are reduced by the use of Na+/H+ exchanger (NHE-1) inhibitors, but these results are mainly obtained using amiloride, a non-selective NHE-1 inhibitor. In bovine PMNs, the role of NHE-1 in functional responses has not been confirmed yet. The aim of this study was to determine the role of NHE-1 using amiloride and zoniporide in pH regulation, ROS production, matrix metalloproteinase 9 (MMP-9) release and calcium flux in bovine PMNs induced by the platelet activation factor (PAF), additionally we evaluated the presence of NHE-1 and NHE-2 mRNA Our data show the presence only of NHE-1 but not NHE-2 in bovine PMNs. Amiloride or zoniporide inhibited the intracellular alkalization induced by PAF without affecting calcium flux. Amiloride diminished ROS production and MMP-9 release, while zoniporide enhanced ROS production without change the MMP-9 release induced by PAF. Our work led us to conclude that changes in intracellular pH induced by PAF are regulated by NHE-1 in bovine neutrophils, but the effects of amiloride on ROS production and MMP-9 release induced by PAF are not NHE-1 dependent.
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Affiliation(s)
- C S Larrazabal
- Laboratory of Molecular Pharmacology, Institute of Pharmacology and Morphophysiology, Faculty of Veterinary Science, Universidad Austral de Chile, PO Box 567, Valdivia, Chile
| | - M D Carretta
- Laboratory of Molecular Pharmacology, Institute of Pharmacology and Morphophysiology, Faculty of Veterinary Science, Universidad Austral de Chile, PO Box 567, Valdivia, Chile
| | - M A Hidalgo
- Laboratory of Molecular Pharmacology, Institute of Pharmacology and Morphophysiology, Faculty of Veterinary Science, Universidad Austral de Chile, PO Box 567, Valdivia, Chile
| | - R A Burgos
- Laboratory of Molecular Pharmacology, Institute of Pharmacology and Morphophysiology, Faculty of Veterinary Science, Universidad Austral de Chile, PO Box 567, Valdivia, Chile.
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7
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Pradhan S, De PB, Punniyamurthy T. Copper(II)-Mediated Chelation-Assisted Regioselective N-Naphthylation of Indoles, Pyrazoles and Pyrrole through Dehydrogenative Cross-Coupling. J Org Chem 2017; 82:4883-4890. [DOI: 10.1021/acs.joc.7b00615] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Sourav Pradhan
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati-781039, India
| | - Pinaki Bhusan De
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati-781039, India
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8
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Sepúlveda C, Palomo I, Fuentes E. Antiplatelet activity of drugs used in hypertension, dyslipidemia and diabetes: Additional benefit in cardiovascular diseases prevention. Vascul Pharmacol 2017; 91:10-17. [DOI: 10.1016/j.vph.2017.03.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 02/03/2017] [Accepted: 03/21/2017] [Indexed: 02/02/2023]
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9
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Sanhueza C, Araos J, Naranjo L, Toledo F, Beltrán AR, Ramírez MA, Gutiérrez J, Pardo F, Leiva A, Sobrevia L. Sodium/proton exchanger isoform 1 regulates intracellular pH and cell proliferation in human ovarian cancer. Biochim Biophys Acta Mol Basis Dis 2017; 1863:81-91. [DOI: 10.1016/j.bbadis.2016.10.013] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Revised: 10/05/2016] [Accepted: 10/18/2016] [Indexed: 12/12/2022]
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10
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Lamoureux L, Radhakrishnan J, Mason TG, Kraut JA, Gazmuri RJ. Adverse postresuscitation myocardial effects elicited by buffer-induced alkalemia ameliorated by NHE-1 inhibition in a rat model of ventricular fibrillation. J Appl Physiol (1985) 2016; 121:1160-1168. [PMID: 27633736 DOI: 10.1152/japplphysiol.00336.2016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Accepted: 09/12/2016] [Indexed: 11/22/2022] Open
Abstract
Major myocardial abnormalities occur during cardiac arrest and resuscitation including intracellular acidosis-partly caused by CO2 accumulation-and activation of the Na+-H+ exchanger isoform-1 (NHE-1). We hypothesized that a favorable interaction may result from NHE-1 inhibition during cardiac resuscitation followed by administration of a CO2-consuming buffer upon return of spontaneous circulation (ROSC). Ventricular fibrillation was electrically induced in 24 male rats and left untreated for 8 min followed by defibrillation after 8 min of cardiopulmonary resuscitation (CPR). Rats were randomized 1:1:1 to the NHE-1 inhibitor zoniporide or vehicle during CPR and disodium carbonate/sodium bicarbonate buffer or normal saline (30 ml/kg) after ROSC. Survival at 240 min declined from 100% with Zoniporide/Saline to 50% with Zoniporide/Buffer and 25% with Vehicle/Buffer (P = 0.004), explained by worsening postresuscitation myocardial dysfunction. Marked alkalemia occurred after buffer administration along with lactatemia that was maximal after Vehicle/Buffer, attenuated by Zoniporide/Buffer, and minimal with Zoniporide/Saline [13.3 ± 4.8 (SD), 9.2 ± 4.6, and 2.7 ± 1.0 mmol/l; P ≤ 0.001]. We attributed the intense postresuscitation lactatemia to enhanced glycolysis consequent to severe buffer-induced alkalemia transmitted intracellularly by an active NHE-1. We attributed the worsened postresuscitation myocardial dysfunction also to severe alkalemia intensifying Na+ entry via NHE-1 with consequent Ca2+ overload injuring mitochondria, evidenced by increased plasma cytochrome c Both buffer-induced effects were ameliorated by zoniporide. Accordingly, buffer-induced alkalemia after ROSC worsened myocardial function and survival, likely through enhancing NHE-1 activity. Zoniporide attenuated these effects and uncovered a complex postresuscitation acid-base physiology whereby blood pH drives NHE-1 activity and compromises mitochondrial function and integrity along with myocardial function and survival.
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Affiliation(s)
- Lorissa Lamoureux
- Resuscitation Institute at Rosalind Franklin University of Medicine and Science, North Chicago, Illinois
| | - Jeejabai Radhakrishnan
- Resuscitation Institute at Rosalind Franklin University of Medicine and Science, North Chicago, Illinois
| | - Thomas G Mason
- Department of Chemistry, University of California, Los Angeles, Los Angeles, California
| | - Jeffrey A Kraut
- Medical and Research Services, Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, California.,Membrane Biology Laboratory, University of California, Los Angeles, Los Angeles, California; and.,Division of Nephrology, Veterans Affairs Greater Los Angeles Healthcare System and David Geffen School of Medicine, Los Angeles, California
| | - Raúl J Gazmuri
- Resuscitation Institute at Rosalind Franklin University of Medicine and Science, North Chicago, Illinois; .,Section of Critical Care Medicine, Captain James A. Lovell Federal Health Care Center, North Chicago, Illinois
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11
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Muscella A, Vetrugno C, Calabriso N, Cossa LG, De Pascali SA, Fanizzi FP, Marsigliante S. [Pt(O,O'-acac)(γ-acac)(DMS)] alters SH-SY5Y cell migration and invasion by the inhibition of Na+/H+ exchanger isoform 1 occurring through a PKC-ε/ERK/mTOR Pathway. PLoS One 2014; 9:e112186. [PMID: 25372487 PMCID: PMC4221608 DOI: 10.1371/journal.pone.0112186] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Accepted: 10/13/2014] [Indexed: 11/19/2022] Open
Abstract
We previously showed that [Pt(O,O'-acac)(γ-acac)(DMS)] ([Pt(acac)2(DMS)]) exerted substantial cytotoxic effects in SH-SY5Y neuroblastoma cells, and decreased metalloproteases (MMPs) production and cells migration in MCF-7 breast cancer cells. The ubiquitously distributed sodium-hydrogen antiporter 1 (NHE1) is involved in motility and invasion of many solid tumours. The present study focuses on the effects of [Pt(acac)2(DMS)] in SH-SY5Y cell migration and also on the possibility that NHE1 may be involved in such effect. After sublethal [Pt(acac)2(DMS)] treatment cell migration was examined by wounding assay and cell invasion by transwell assay. NHE1 activity was measured in BCECF-loaded SH-SY5Y as the rate of Na+-dependent intracellular pH recovery in response to an acute acid pulse. Gelatin zymography for MMP-2/9 activities, Western blottings of MMPs, MAPKs, mTOR, S6 and PKCs and small interfering RNAs to PKC-ε/-δ mRNA were performed. Sublethal concentrations of [Pt(acac)2(DMS)] decreases NHE1 activity, inhibits cell migration and invasion and decreases expression and activity of MMP-2 and -9. [Pt(acac)2(DMS)] administered to SH-SY5Y cells provokes the increment of ROS, generated by NADPH oxidase, responsible for the PKC-ε and PKC-δ activation. Whilst PKC-δ activates p38/MAPK, responsible for the inhibition of MMP-2 and -9 secretion, PKC-ε activates a pathway made of ERK1/2, mTOR and S6K responsible for the inhibition of NHE1 activity and cell migration. In conclusion, we have shown a drastic impairment in tumour cell metastatization in response to inhibition of NHE1 and MMPs activities by [Pt(acac)2(DMS)] occurring through a novel mechanism mediated by PKC-δ/-ε activation.
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Affiliation(s)
- Antonella Muscella
- Cell Pathology Lab, Dipartimento di Scienze e Tecnologie Biologiche e Ambientali (Di.S.Te.B.A.), Salento University, Lecce, Italy
| | - Carla Vetrugno
- Neuropathology Unit, Istituto di Neurologia sperimentale e Divisione di Neuroscienze, Istituto Scientifico IRCCS San Raffaele (sezione di Lecce), Milano, Italy
| | - Nadia Calabriso
- Cell Physiology Lab, Dipartimento di Scienze e Tecnologie Biologiche e Ambientali (Di.S.Te.B.A.), Salento University, Lecce, Italy
| | - Luca Giulio Cossa
- Cell Physiology Lab, Dipartimento di Scienze e Tecnologie Biologiche e Ambientali (Di.S.Te.B.A.), Salento University, Lecce, Italy
| | - Sandra Angelica De Pascali
- General and Inorganic Chemistry Lab, Dipartimento di Scienze e Tecnologie Biologiche e Ambientali (Di.S.Te.B.A.), Salento University, Lecce, Italy
| | - Francesco Paolo Fanizzi
- General and Inorganic Chemistry Lab, Dipartimento di Scienze e Tecnologie Biologiche e Ambientali (Di.S.Te.B.A.), Salento University, Lecce, Italy
| | - Santo Marsigliante
- Cell Physiology Lab, Dipartimento di Scienze e Tecnologie Biologiche e Ambientali (Di.S.Te.B.A.), Salento University, Lecce, Italy
- * E-mail:
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12
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Quansah H, N'Gouemo P. Amiloride and SN-6 suppress audiogenic seizure susceptibility in genetically epilepsy-prone rats. CNS Neurosci Ther 2014; 20:860-6. [PMID: 24948133 DOI: 10.1111/cns.12296] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Revised: 05/12/2014] [Accepted: 05/13/2014] [Indexed: 01/27/2023] Open
Abstract
AIMS We have recently reported that amiloride, a potent and nonselective blocker of acid-sensing ion channels, prevents the development of pilocarpine-induced seizures and status epilepticus. Amiloride is also known to suppress the activity of Na(+) /Ca(2+) and Na(+) /H(+) exchangers that have been implicated in the pathophysiology of seizures. Here, we evaluated the effects of amiloride, SN-6 (a potent blocker of Na(+) /Ca(2+) exchangers) and zoniporide (a potent blocker of Na(+) /H(+) exchangers) on acoustically evoked seizures (audiogenic seizures, AGS) in genetically epilepsy-prone rats (GEPR-3s), a model of inherited generalized epilepsy. METHODS Male, six-week-old GEPR-3s were used. The GEPR-3s were tested for AGS susceptibility before and after treatment with various doses of amiloride, SN-6, and zoniporide (1, 3, 10, and 30 mg/kg; per os). RESULTS We found that pretreatment with amiloride and SN-6 markedly reduced the incidence and severity of AGS in the GEPR-3s. In contrast, administration of zoniporide only minimally reduced the incidence and severity of AGS in the GEPR-3s. A combination of noneffective doses of SN-6 and zoniporide also suppressed AGS susceptibility in the GEPR-3s. CONCLUSIONS These findings suggest acid-sensing ion channels and the Na(+) /Ca(2+) exchanger may play an important role in the pathophysiology of inherited AGS susceptibility in the GEPR-3s.
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Affiliation(s)
- Hillary Quansah
- Department of Pediatrics, Georgetown University Medical Center, Washington, DC, USA
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13
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AMPA receptor pHluorin-GluA2 reports NMDA receptor-induced intracellular acidification in hippocampal neurons. Proc Natl Acad Sci U S A 2013; 110:14426-31. [PMID: 23940334 DOI: 10.1073/pnas.1312982110] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
NMDA receptor activation promotes endocytosis of AMPA receptors, which is an important mechanism underlying long-term synaptic depression. The pH-sensitive GFP variant pHluorin fused to the N terminus of GluA2 (pH-GluA2) has been used to assay NMDA-mediated AMPA receptor endocytosis and recycling. Here, we demonstrate that in somatic and dendritic regions of hippocampal neurons a large fraction of the fluorescent signal originates from intracellular pH-GluA2, and that the decline in fluorescence in response to NMDA and AMPA primarily describes an intracellular acidification, which quenches the pHluorin signal from intracellular receptor pools. Neurons expressing an endoplasmic reticulum-retained mutant of GluA2 (pH-GluA2 ΔC49) displayed a larger response to NMDA than neurons expressing wild-type pH-GluA2. A similar NMDA-elicited decline in pHluorin signal was observed by expressing cytosolic pHluorin alone without fusion to GluA2 (cyto-pHluorin). Intracellular acidification in response to NMDA was further confirmed by using the ratiometric pH indicator carboxy-SNARF-1. The NMDA-induced decline was followed by rapid recovery of the fluorescent signal from both cyto-pHluorin and pH-GluA2. The recovery was sodium-dependent and sensitive to Na(+)/H(+)-exchanger (NHE) inhibitors. Moreover, recovery was more rapid after shRNA-mediated knockdown of the GluA2 binding PDZ domain-containing protein interacting with C kinase 1 (PICK1). Interestingly, the accelerating effect of PICK1 knockdown on the fluorescence recovery was eliminated in the presence of the NHE1 inhibitor zoniporide. Our results indicate that the pH-GluA2 recycling assay is an unreliable assay for studying AMPA receptor trafficking and also suggest a role for PICK1 in regulating intracellular pH via modulation of NHE activity.
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14
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Babich V, Vadnagara K, Di Sole F. The biophysical and molecular basis of intracellular pH sensing by Na+/H+ exchanger-3. FASEB J 2013; 27:4646-58. [PMID: 23934281 DOI: 10.1096/fj.12-225466] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Epithelial Na(+)/H(+) exchanger-3 (NHE3) transport is fundamental for renal and intestinal sodium reabsorption. Cytoplasmic protons are thought to serve as allosteric modifiers of the exchanger and to trigger its transport through protein conformational change. This effect presupposes an intracellular pH (pHi) dependence of NHE3 activity, although the biophysical and molecular basis of NHE3 pHi sensitivity have not been defined. NHE3, when complexed with the calcineurin homologous protein-1 (CHP1), had a shift in pHi sensitivity (0.4 units) toward the acidic side in comparison with NHE3 alone, as measured by oscillating pH electrodes combined with whole-cell patch clamping. Indeed, CHP1 interaction with NHE3 inhibited NHE3 transport in a pHi -dependent manner. CHP1 binding to NHE3 also affected its acute regulation. Intracellular perfusion of peptide from the CHP1 binding region (or pHi modification to reduce the CHP1 amount bound to NHE3) was permissive and cooperative for dopamine inhibition of NHE3 but reversed that of adenosine. Thus, CHP1 interaction with NHE3 apparently establishes the exchanger set point for pHi, and modification in this set point is effective in the hormonal stimuli-mediated regulation of NHE3. CHP1 may serve as a regulatory cofactor for NHE3 conformational change, dependent on intracellular protonation.
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Affiliation(s)
- Victor Babich
- 1Department of Medicine, University of Maryland School of Medicine, 20 Penn Street, HSFII, Suite S005, Baltimore, MD 21201, USA.
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15
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Roginiel AC, Kohut DL, Kaur S, Saleh AMA, Weber T, Geibel P, Singh H, Geibel JP. Effect of NSAIDs on Na⁺/H⁺ exchanger activity in rat colonic crypts. Am J Physiol Cell Physiol 2013; 305:C512-8. [PMID: 23739181 DOI: 10.1152/ajpcell.00303.2012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Nonsteroidal anti-inflammatory drugs (NSAIDs; 1) are widely recommended for several acute and chronic conditions. For example, both indomethacin and aspirin are taken for pain relief. Aspirin is also used for prevention of myocardial infarction, and indomethacin can be administered orally or as a suppository for patients with rheumatoid disease and other chronic inflammatory states. However, use of NSAIDs can cause damage to the mucosal barrier surrounding the gastrointestinal (GI) tract, increasing the risk of ulcer formation. While microencapsulation of NSAIDs has been shown to reduce upper GI injury, sustained release in the lower GI tract and colon may cause epithelial erosion due to increased acidification. The use of suppositories has also been linked to rectal and lower GI bleeding. In this study, we investigated the role of NSAIDs aspirin and indomethacin on Na⁺/H⁺ exchanger (NHE) activity in rat colonic crypts. By comparing average rates of pH recovery between control and NSAID perfusion runs, we were able to determine that both aspirin and indomethacin increase hydrogen extrusion into the colonic lumen. Through treatment with 5-ethylisopropyl amiloride (EIPA), amiloride, and zoniporide dihydrochloride, we further demonstrated that indomethacin specifically enhances proton excretion through regulation of apical NHE-3 and NHE-2 and to a lesser extent on basolateral NHE-1 and NHE-4. Our results suggest that clinical exposure to NSAIDs may affect colonic tissue at the site of selected NHE isoforms, resulting in modulation of transport and barrier function.
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Affiliation(s)
- Aliya C Roginiel
- Department of Surgery, Yale University School of Medicine, New Haven, Connecticut, USA
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16
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Provost JJ, Wallert MA. Inside out: targeting NHE1 as an intracellular and extracellular regulator of cancer progression. Chem Biol Drug Des 2013; 81:85-101. [PMID: 23253131 DOI: 10.1111/cbdd.12035] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The sodium hydrogen exchanger isoform one is a critical regulator of intracellular pH, serves as an anchor for the formation of cytoplasmic signaling complexes, and modulates cytoskeletal organization. There is a growing interest in the potential for sodium hydrogen exchanger isoform one as a therapeutic target against cancer. Sodium hydrogen exchanger isoform one transport drives formation of membrane protrusions essential for cell migration and contributes to the establishment of a tumor microenvironment that leads to the rearrangement of the extracellular matrix further supporting tumor progression. Here, we focus on the potential impact that an inexpensive, $100 genome would have in identifying prospective therapeutic targets to treat tumors based upon changes in gene expression and variation of sodium hydrogen exchanger isoform one regulators. In particular, we will focus on the ezrin, radixin, moesin family proteins, calcineurin B homologous proteins, Ras/Raf/MEK/ERK signaling, and phosphoinositide signaling as they relate to the regulation of sodium hydrogen exchanger isoform one in cancer progression.
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Affiliation(s)
- Joseph J Provost
- Center for Biopharmaceutical Research and Production, North Dakota State University, Fargo, ND 58102, USA.
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17
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Tai KK, Truong DD. Amiloride but not memantine reduces neurodegeneration, seizures and myoclonic jerks in rats with cardiac arrest-induced global cerebral hypoxia and reperfusion. PLoS One 2013; 8:e60309. [PMID: 23593189 PMCID: PMC3620224 DOI: 10.1371/journal.pone.0060309] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2012] [Accepted: 02/26/2013] [Indexed: 01/02/2023] Open
Abstract
It has been reported that both activation of N-methyl-D-aspartate receptors and acid-sensing ion channels during cerebral ischemic insult contributed to brain injury. But which of these two molecular targets plays a more pivotal role in hypoxia-induced brain injury during ischemia is not known. In this study, the neuroprotective effects of an acid-sensing cation channel blocker and an N-methyl-D-aspartate receptor blocker were evaluated in a rat model of cardiac arrest-induced cerebral hypoxia. We found that intracisternal injection of amiloride, an acid-sensing ion channel blocker, dose-dependently reduced cerebral hypoxia-induced neurodegeneration, seizures, and audiogenic myoclonic jerks. In contrast, intracisternal injection of memantine, a selective uncompetitive N-methyl-D-aspartate receptor blocker, had no significant effect on cerebral hypoxia-induced neurodegeneration, seizure and audiogenic myoclonic jerks. Intracisternal injection of zoniporide, a specific sodium-hydrogen exchanger inhibitor, before cardiac arrest-induced cerebral hypoxia, also did not reduce cerebral hypoxia-induced neurodegeneration, seizures and myoclonic jerks. These results suggest that acid-sensing ion channels play a more pivotal role than N-methyl-D-aspartate receptors in mediating cerebral hypoxia-induced brain injury during ischemic insult.
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Affiliation(s)
- Kwok Keung Tai
- The Parkinson's and Movement Disorder Research Laboratory, Long Beach Memorial Medical Center, Long Beach, California, United States of America.
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18
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Dalvie D, Xiang C, Kang P, Zhou S. Interspecies variation in the metabolism of zoniporide by aldehyde oxidase. Xenobiotica 2012; 43:399-408. [DOI: 10.3109/00498254.2012.727499] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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19
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Blockade of peripheral and spinal Na+/H+ exchanger increases formalin-induced long-lasting mechanical allodynia and hyperalgesia in rats. Brain Res 2012; 1475:19-30. [DOI: 10.1016/j.brainres.2012.08.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2012] [Revised: 07/31/2012] [Accepted: 08/01/2012] [Indexed: 12/14/2022]
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20
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Zhou Y, Gong G, Yang W, Wang Y, Xu J, Xu Y. The cardioprotective effect of TG-6, a newly synthesized compound, on ischemia-reperfusion injury in rats. Eur J Pharmacol 2012; 683:190-6. [PMID: 22425651 DOI: 10.1016/j.ejphar.2012.01.047] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2011] [Revised: 01/22/2012] [Accepted: 01/28/2012] [Indexed: 10/28/2022]
Abstract
We tested 3-nitro-4-((4-(2,3,4-trimethoxybenzyl)piperazin-1-yl)methyl) benzoylguanidine tartrate (TG-6) which is combinated of two known cardioprotective agents cariporide and trimetazidine, whether additively to reduce ischemia-reperfusion injury in rats. Using models of in vitro perfusion (Langendorff system) and in vivo open chest left anterior descending coronary artery ligation causing ischemia-reperfusion injury. We also used Fura-2 to measure the cytosolic Ca²⁺ concentrations ([Ca²⁺]i) in cardiomyocytes, western blot analysis the protein expression of Kv1.4, Kv4.2, Kv4.3 in myocardial ischemia-reperfusion rats. TG-6 improved the cardiac function in both in vivo and in vitro models, lowered Lactate Dehydrogenase (LDH), Creatine Kinase (CK), Malodialdehyed (MDA) activity while enhanced Superoxide Dismutase (SOD) activity. High dose of TG-6 improved the hypoxia injury of cardiomyocytes induced by sodium dithionite (Na₂S₂O₄), enhanced the viability and decreased the [Ca²⁺]i. It also down-regulated the expression of Kv1.4 and increased the expression of Kv4.2 and Kv4.3, so it might through regulating the expression of the transient outward potassium current (Ito) to improve the cardiac function.
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Affiliation(s)
- Yi Zhou
- Department of Pharmacology, China Pharmaceutical University, Nanjing, China
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21
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Santos-Torres J, Ślimak MA, Auer S, Ibañez-Tallon I. Cross-reactivity of acid-sensing ion channel and Na⁺-H⁺ exchanger antagonists with nicotinic acetylcholine receptors. J Physiol 2011; 589:5109-23. [PMID: 21911609 DOI: 10.1113/jphysiol.2011.213272] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Nicotinic acetylcholine receptors (nAChRs) are widely distributed throughout the mammalian central and peripheral nervous systems, where they contribute to neuronal excitability and synaptic communication. It has been reported that nAChRs are modulated by BK channels and that BK channels, in turn, are inhibited by acid-sensing ion channels (ASICs). Here we investigate the possible functional interaction between these channels in medial habenula (MHb) neurones. We report that selective antagonists of large-conductance calcium-activated potassium channels and ASIC1a channels, paxilline and psalmotoxin 1, respectively, did not induce detectable changes in nicotine-evoked currents. In contrast, the non-selective ASIC and Na(+)-H(+) exchanger (NHE1) antagonists, amiloride and its analogues, suppressed nicotine-evoked responses in MHb neurones of wild-type and ASIC2 null mice, excluding a possible involvement of ASIC2 in the nAChR inhibition by amiloride. Zoniporide, a more selective inhibitor of NHE1, reversibly inhibited α3β4-, α7- and α4-containing (*) nAChRs in Xenopus oocytes and in brain slices, as well as in PS120 cells deficient in NHE1 and virally transduced with nAChRs, suggesting a generalized effect of zoniporide in most neuronal nAChR subtypes. Independently from nAChR antagonism, zoniporide profoundly blocked synaptic transmission onto MHb neurones without affecting glutamatergic and GABA receptors. Taken together, these results indicate that amiloride and zoniporide, which are clinically used to treat hypertension and cardiovascular disease, have an inhibitory effect on neuronal nAChRs when used experimentally at high doses. The possible cross-reactivity of these compounds with nAChRs in vivo will require further investigation.
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Affiliation(s)
- Julio Santos-Torres
- Molecular Neurobiology Group, Department of Neuroscience, Max-Delbrück-Centrum, Berlin, Germany
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22
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Role of the spinal Na+/H+ exchanger in formalin-induced nociception. Neurosci Lett 2011; 501:4-9. [DOI: 10.1016/j.neulet.2011.06.048] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2011] [Revised: 06/24/2011] [Accepted: 06/26/2011] [Indexed: 11/18/2022]
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23
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Gao L, Tsun J, Sun L, Kwan J, Watson A, Macdonald PS, Hicks M. Critical role of the STAT3 pathway in the cardioprotective efficacy of zoniporide in a model of myocardial preservation - the rat isolated working heart. Br J Pharmacol 2011; 162:633-47. [PMID: 20942815 PMCID: PMC3041253 DOI: 10.1111/j.1476-5381.2010.01071.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2010] [Revised: 08/23/2010] [Accepted: 09/21/2010] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND AND PURPOSE Ischemia-reperfusion injury plays an important role in the development of primary allograft failure after heart transplantation. Inhibition of the Na+/H+ exchanger is one of the most promising therapeutic strategies for treating ischemia-reperfusion injury. Here we have characterized the cardioprotective efficacy of zoniporide and the underlying mechanisms in a model of myocardial preservation using rat isolated working hearts. EXPERIMENTAL APPROACH Rat isolated hearts subjected to 6 h hypothermic (1-4°C) storage followed by 45 min reperfusion at 37°C were treated with zoniporide at different concentrations and timing. Recovery of cardiac function, levels of total and phosphorylated protein kinase B, extracellular signal-regulated kinase 1/2, glycogen synthase kinase-3β and STAT3 as well as cleaved caspase 3 were measured at the end of reperfusion. Lactate dehydrogenase release into coronary effluent before and post-storage was also measured. KEY RESULTS Zoniporide concentration-dependently improved recovery of cardiac function after reperfusion. The functional recovery induced by zoniporide was accompanied by up-regulation of p-extracellular signal-regulated kinase 1/2 and p-STAT3, and by reduction in lactate dehydrogenase release and cleaved caspase 3. There were no significant differences in any of the above indices when zoniporide was administered before, during or after ischemia. The STAT3 inhibitor, stattic, abolished zoniporide-induced improvements in functional recovery and up-regulation of p-STAT3 after reperfusion. CONCLUSIONS AND IMPLICATIONS Zoniporide is a potent cardioprotective agent and activation of STAT3 plays a critical role in the cardioprotective action of zoniporide. This agent shows promise as a supplement to storage solutions to improve preservation of donor hearts.
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Affiliation(s)
- L Gao
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW, Australia
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24
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Jung IS, Lee SH, Yang MK, Park JW, Yi KY, Yoo SE, Kwon SH, Chung HJ, Choi WS, Shin HS. Cardioprotective effects of the novel Na+/H+ exchanger-1 inhibitor KR-32560 in a perfused rat heart model of global ischemia and reperfusion: Involvement of the Akt-GSK-3β cell survival pathway and antioxidant enzyme. Arch Pharm Res 2010; 33:1241-51. [DOI: 10.1007/s12272-010-0815-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2010] [Revised: 06/12/2010] [Accepted: 06/14/2010] [Indexed: 11/29/2022]
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25
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Dalvie D, Zhang C, Chen W, Smolarek T, Obach RS, Loi CM. Cross-Species Comparison of the Metabolism and Excretion of Zoniporide: Contribution of Aldehyde Oxidase to Interspecies Differences. Drug Metab Dispos 2009; 38:641-54. [DOI: 10.1124/dmd.109.030783] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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26
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Murphy E, Allen DG. Why did the NHE inhibitor clinical trials fail? J Mol Cell Cardiol 2009; 46:137-41. [PMID: 19027021 PMCID: PMC2661870 DOI: 10.1016/j.yjmcc.2008.09.715] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2008] [Revised: 09/16/2008] [Accepted: 09/18/2008] [Indexed: 11/25/2022]
Affiliation(s)
- Elizabeth Murphy
- National Heart, Lung and Blood Institute, NIH, Bethesda, MD 20892, USA.
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27
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Pettersen JC, Chouinard L, Kerlin RL, Groom SN, Botts S, Arezzo JC, Boucher MA, Frazier DE, Buchholz AR. Neurotoxic Effects of Zoniporide: A Selective Inhibitor of the Na+/H+ Exchanger Isoform 1. Toxicol Pathol 2008; 36:608-19. [DOI: 10.1177/0192623308318215] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Zoniporide, an inhibitor of the Na+-H+ exchanger-1, was administered by continuous intravenous infusion to rats and dogs for up to 1 month. In 1-month studies, histological and functional changes were observed in select portions of the peripheral nervous system; however, these findings were not detected in 2-week studies at similar or higher doses. In the 1-month rat study, there was dose-dependent, minimal, focal, or multifocal nerve fiber (axonal) degeneration in the spinal cord and/or sciatic nerve. In a follow-up rat study, findings included slowing of caudal nerve conduction velocity and axonal degeneration in the spinal cord (dorsal funiculus), dorsal roots, dorsal root ganglia (DRG), radial, sciatic, and tibial nerves. In the 1-month dog study, there was impairment of the patellar reflex and associated postural reaction changes, minimal to marked proximal nerve fiber degeneration in the DRG, and minimal nerve fiber degeneration in the dorsal roots and funiculi of the spinal cord. Minimal nerve fiber degeneration of equivocal significance was noted in various peripheral nerves. Taken together, these findings were consistent with a specific effect on peripheral sensory nerve fibers. These studies demonstrated that zoniporide produces clinical, electrophysiologic, and microscopic evidence of peripheral sensory axonopathy and establishes the importance of careful preclinical evaluation of neurological function.
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Affiliation(s)
- John C. Pettersen
- Pfizer Global Research and Development, Groton/New London Laboratories, Pfizer Inc., Groton, Connecticut, USA
| | - Luc Chouinard
- Charles River Laboratories, Preclinical Services, Montréal, Quebec, Canada
| | - Roy L. Kerlin
- Pfizer Global Research and Development, Groton/New London Laboratories, Pfizer Inc., Groton, Connecticut, USA
| | - Simon N. Groom
- Charles River Laboratories, Preclinical Services, Montréal, Quebec, Canada
| | - Suzanne Botts
- GlaxoSmithKline, Safety Assessment, Research Triangle Park, North Carolina, USA
| | - Joseph C. Arezzo
- Albert Einstein College of Medicine, Departments of Neuroscience and Neurology, Bronx, New York, USA
| | - Mary A. Boucher
- Pfizer Global Research and Development, Groton/New London Laboratories, Pfizer Inc., Groton, Connecticut, USA
| | | | - Allan R. Buchholz
- Pfizer Global Research and Development, Groton/New London Laboratories, Pfizer Inc., Groton, Connecticut, USA
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28
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Liu CN, Somps CJ. Na+/H+ Exchanger-1 Inhibitors Reduce Neuronal Excitability and Alter Na+ Channel Inactivation Properties in Rat Primary Sensory Neurons. Toxicol Sci 2008; 103:346-53. [DOI: 10.1093/toxsci/kfn045] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
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29
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Williams IA, Xiao XH, Ju YK, Allen DG. The rise of [Na+]i during ischemia and reperfusion in the rat heart—underlying mechanisms. Pflugers Arch 2007; 454:903-12. [PMID: 17356886 DOI: 10.1007/s00424-007-0241-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2007] [Accepted: 02/18/2007] [Indexed: 10/23/2022]
Abstract
Intracellular Na(+) concentration ([Na(+)](i)) rises in the heart during ischemia, and on reperfusion, there is a transient rise followed by a return toward control. These changes in [Na(+)](i) contribute to ischemic and reperfusion damage through their effects on Ca(2+) overload. Part of the rise of [Na(+)](i) during ischemia may be caused by increased activity of the cardiac Na(+)/H(+) exchanger (NHE1), activated by the ischemic rise in [H(+)](i). In support of this view, NHE1 inhibitors reduce the [Na(+)](i) rise during ischemia. Another possibility is that the rise of [Na(+)](i) during ischemia is caused by Na(+) influx through channels. We have reexamined these issues by use of two different NHE1 inhibitors, amiloride, and zoniporide, in addition to tetrodotoxin (TTX), which blocks voltage-sensitive Na(+) channels. All three drugs produced cardioprotection after ischemia, but amiloride (100 microM) and TTX (300 nM) prevented the rise in [Na(+)](i) during ischemia, whereas zoniporide (100 nM) did not. Both amiloride and zoniporide prevented the rise of [Na(+)](i) on reperfusion, whereas TTX was without effect. In an attempt to explain these differences, we measured the ability of the three drugs to block Na(+) currents. At the concentrations used, TTX reduced the transient Na(+) current (I (Na)) by 11 +/- 2% while amiloride and zoniporide were without effect. In contrast, TTX largely eliminated the persistent Na(+) current (I (Na,P)) and amiloride was equally effective, whereas zoniporide had a substantially smaller effect reducing I (Na,P) to 41 +/- 8%. These results suggest that part of the effect of NHE1 inhibitors on the [Na(+)](i) during ischemia is by blockade of I (Na,P). The fact that a low concentration of TTX eliminated the rise of [Na(+)](i) during ischemia suggests that I (Na,P) is a major source of Na(+) influx in this model of ischemia.
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Affiliation(s)
- Iwan A Williams
- Bosch Institute and School of Medical Sciences, University of Sydney, F13 Sydney, NSW 2006, Australia
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30
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Suen YF, Hope H, Nantz MH, Haddadin MJ, Kurth AMJ. Transannular Anti-Michael Addition: Formation of 4H-Pyrazolo[5,1-c]thiazines. Tetrahedron Lett 2006; 47:7893-7896. [PMID: 21904417 DOI: 10.1016/j.tetlet.2006.09.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The reaction of 2-(diphenylmethylene)thietan-3-one (2) with 1,2,4,5-tetrazines (3a-c) in KOH/MeOH/THF gives 4H-pyrazolo[5,1-c]thiazines (7a-c). This no vel condensation reaction proceeds via the intermediacy of an 8-(diphenylmethylene)-2H-1,4,5-thiadiazocin-7(8H)-one (5), which undergoes a multi-step rearrangement including a rare anti-Michael addition.
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Affiliation(s)
- Yat Fan Suen
- Department of Chemistry, University of California, Davis, CA 95616, USA
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31
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Lee KS, Park JW, Jin YR, Jung IS, Cho MR, Yi KY, Yoo SE, Chung HJ, Yun YP, Park TK, Shin HS. Antiplatelet activity of [5-(2-methoxy-5-chlorophenyl)furan-2-ylcarbonyl]guanidine (KR-32570), a novel sodium/hydrogen exchanger-1 and its mechanism of action. Arch Pharm Res 2006; 29:375-83. [PMID: 16756082 DOI: 10.1007/bf02968587] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
The antiplatelet effects of a novel guanidine derivative, KR-32570 ([5-(2-methoxy-5-chlorophenyl) furan-2-ylcarbonyl]guanidine), were investigated with an emphasis on the mechanisms underlying its inhibition of collagen-induced platelet aggregation. KR-32570 significantly inhibited the aggregation of washed rabbit platelets induced by collagen (10 microg/mL), thrombin (0.05 U/mL), arachidonic acid (100 microM), a thromboxane (TX) A2 mimetic agent U46619 (9,11-dideoxy-9,11-methanoepoxy-prostaglandin F2, 1 microM) and a Ca2+ ATPase inhibitor thapsigargin (0.5 microM) (IC50 values: 13.8 +/- 1.8, 26.3 +/- 1.2, 8.5 +/- 0.9, 4.3 +/- 1.7 and 49.8 +/- 1.4 microM, respectively). KR-32570 inhibited the collagen-induced liberation of [3H]arachidonic acid from the platelets in a concentration dependent manner with complete inhibition being observed at 50 microM. The TXA2 synthase assay showed that KR-32570 also inhibited the conversion of the substrate PGH2 to TXB2 at all concentrations. Furthermore, KR-32570 significantly inhibited the [Ca2+]i mobilization induced by collagen at 50 microM, which is the concentration that completely inhibits platelet aggregation. KR-32570 also decreased the level of collagen (10 microg/mL)-induced secretion of serotonin from the dense-granule contents of platelets, and inhibited the NHE-1-mediated rabbit platelet swelling induced by intracellular acidification. These results suggest that the antiplatelet activity of KR-32570 against collagen-induced platelet aggregation is mediated mainly by inhibiting the release of arachidonic acid, TXA2 synthase, the mobilization of cytosolic Ca2+ and NHE-1.
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Affiliation(s)
- Kyung-Sup Lee
- College of Pharmacy, Chungbuk National University, Cheongju 361-763, Korea
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Park JW, Roh HY, Jung IS, Yun YP, Yi KY, Yoo SE, Kwon SH, Chung HJ, Shin HS. Effects of [5-(2-methoxy-5-fluorophenyl)furan-2-ylcarbonyl]guanidine (KR-32560), a novel sodium/hydrogen exchanger-1 inhibitor, on myocardial infarct size and ventricular arrhythmias in a rat model of ischemia/reperfusion heart injury. J Pharmacol Sci 2005; 98:439-49. [PMID: 16082174 DOI: 10.1254/jphs.fp0050078] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
The cardioprotective effects of the novel sodium/hydrogen exchanger-1 (NHE-1) inhibitor KR-32560 {[5-(2-methoxy-5-fluorophenyl)furan-2-ylcarbonyl]guanidine} were studied in an anesthetized rat model of 30-min ischemia / 2.5-h reperfusion heart injury. KR-32560 (0.01 - 1 microM) dose-dependently inhibited NHE-1-mediated rabbit platelet swelling induced by intracellular acidification. KR-32560 at 0.1 and 1.0 mg/kg (i.v. bolus, given 10 min before ischemia) reduced infarct size from 65.9% (control) to 49.7% and 32.7%, respectively, while reducing the extension of myocardial injury (mm(3)/g of left heart weight) from 405.1 (control) to 302.9 and 185.4, respectively (all P<0.05 vs control). KR-32560 dose-dependently reduced the total number of ventricular premature beats (VPBs) during ischemia from 510.2 (control) to 353.8 and 134.2 beats (all P<0.05, n = 6), while reducing ventricular tachycardia (VT) incidence from 49.3 (control) to 26.8 and 4.3 and VT duration from 249.2 s (control) to 150.5 and 26.7 s (all P<0.05, n = 6). KR-32560 dose-dependently reduced ventricular fibrillation (VF) incidence from 19.0 (control) to 9.2 and 1.2 and VF duration from 88.0 s to 34.5 and 2.8 s (all P<0.05, n = 6). KR-32560 also exerted similar effects on reperfusion arrhythmias, except for VPBs. These results indicate that KR-32560 may exert significant cardioprotective effects in ischemia/reperfusion heart injury.
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Affiliation(s)
- Jung-Woo Park
- Department of Applied Biochemistry, Division of Life Science, College of Biomedical and Health Science, Konkuk University, Chungju 380-701, Korea
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Roh HY, Jung IS, Park JW, Yun YP, Yi KY, Yoo SE, Kwon SH, Chung HJ, Shin HS. Cardioprotective effects of [5-(2-methyl-5-fluorophenyl)furan-2-ylcarbonyl]guanidine (KR-32568) in an anesthetized rat model of ischemia and reperfusion heart injury. Pharmacology 2005; 75:37-44. [PMID: 15942274 DOI: 10.1159/000086192] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2005] [Accepted: 04/11/2005] [Indexed: 11/19/2022]
Abstract
The effects of a novel sodium/hydrogen exchanger-1 (NHE-1) inhibitor, KR-32568, were studied in an anesthetized rat model of 30 min ischemia/2.5 h reperfusion heart injury. KR-32568 dose-dependently inhibited NHE-1-mediated rabbit platelet swelling induced by intracellular acidification. In our anesthetized rat model, KR-32568 reduced infarct size from 67 (control) to 43 and 24% at 0.1 and 1.0 mg/kg (i.v. bolus, given 10 min before ischemia), respectively. KR-32568 at the same doses also significantly reduced the total number of ventricular premature beats during ischemia/reperfusion from 530 (control) to 266 and 115 beats, ventricular tachycardia (VT) incidence from 51 (control) to 21 and 8, VT duration from 238 s (control) to 63 and 33 s, ventricular fibrillation (VF) incidence from 17 (control) to 8 and 0, and VF duration from 85 s to 18 and 1 s. These results indicate that KR-32568 may exert potent cardioprotective effects in rats via inhibition of sodium/hydrogen exchanger-1.
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Affiliation(s)
- Hui-Yul Roh
- Department of Applied Biochemistry, Division of Life Science, College of Biomedical and Health Science, Konkuk University, Chungju, Korea
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Clements-Jewery H, Sutherland FJ, Allen MC, Tracey WR, Avkiran M. Cardioprotective efficacy of zoniporide, a potent and selective inhibitor of Na+/H+ exchanger isoform 1, in an experimental model of cardiopulmonary bypass. Br J Pharmacol 2004; 142:57-66. [PMID: 15037516 PMCID: PMC1574931 DOI: 10.1038/sj.bjp.0705749] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
1. We determined (1) the inhibitory potency of zoniporide against the native Na(+)/H(+) exchanger isoform 1 (NHE1) that is expressed in adult rat ventricular myocytes and platelets, and (2) the cardioprotective efficacy of zoniporide in isolated, blood-perfused adult rat hearts subjected to cardioplegic arrest, hypothermic ischaemia (150 min at 25 degrees C) and normothermic reperfusion (60 min at 37 degrees C). 2. In isolated myocytes, in which NHE1 activity was determined directly by measurement of H(+) efflux rate following intracellular acidification, zoniporide produced a dose-dependent inhibition of such activity (IC(50) 73 nm at 25 degrees C). A comparable NHE1-inhibitory potency was retained at 37 degrees C. 3. In platelets, in which the rate of cell swelling was used as a surrogate index of NHE1 activity, this was again inhibited by zoniporide (IC(50) 67 nm at 25 degrees C). 4. In the isolated heart model, administration of zoniporide (loading bolus of 1 mg kg(-1) i.v. plus continuous infusion at 1.98 mg kg(-1) h(-1) i.v.) to the support animal achieved a free plasma drug concentration of >/=1 microm. At this dose, zoniporide afforded significant cardioprotective benefit relative to vehicle treatment, with improved preservation of left ventricular end-diastolic and developed pressures and coronary perfusion pressure during reperfusion. Myocardial myeloperoxidase activity was also attenuated by zoniporide treatment, indicating reduced neutrophil accumulation. 5. These data show that zoniporide (1) is a potent inhibitor of native NHE1 activity in ventricular myocytes and platelets, and (2) affords significant cardioprotective benefit during ischaemia and reperfusion in an experimental model that mimics several distinctive features of human cardioplegic arrest with cardiopulmonary bypass.
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Affiliation(s)
- Hugh Clements-Jewery
- Centre for Cardiovascular Biology and Medicine, King's College London, The Rayne Institute, St Thomas' Hospital, London
| | - Fiona J Sutherland
- Centre for Cardiovascular Biology and Medicine, King's College London, The Rayne Institute, St Thomas' Hospital, London
| | - Mary C Allen
- Pfizer Global Research and Development, Groton, CT, U.S.A
| | - W Ross Tracey
- Pfizer Global Research and Development, Groton, CT, U.S.A
| | - Metin Avkiran
- Centre for Cardiovascular Biology and Medicine, King's College London, The Rayne Institute, St Thomas' Hospital, London
- Author for correspondence:
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Tracey WR, Allen MC, Frazier DE, Fossa AA, Johnson CG, Marala RB, Knight DR, Guzman-Perez A. Zoniporide: a potent and selective inhibitor of the human sodium-hydrogen exchanger isoform 1 (NHE-1). CARDIOVASCULAR DRUG REVIEWS 2003; 21:17-32. [PMID: 12595915 DOI: 10.1111/j.1527-3466.2003.tb00103.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The sodium-hydrogen exchanger isoform-1 (NHE-1) plays an important role in the myocardial response to ischemia-reperfusion; inhibition of this exchanger protects against ischemic injury, including reduction in infarct size. Herein we describe a novel, potent, and highly selective NHE-1 inhibitor, zoniporide (CP-597,396; [1-(quinolin-5-yl)-5-cyclopropyl-1H-pyrazole-4-carbonyl] guanidine). Zoniporide inhibits human NHE-1 with an IC(50) of 14 nM, has >150-fold selectivity vs. other NHE isoforms, and potently inhibits ex vivo NHE-1-dependent swelling of human platelets. This compound is well tolerated in preclinical animal models, exhibits moderate plasma protein binding, has a t(1/2) of 1.5 h in monkeys, and has one major active metabolite. In both in vitro and in vivo rabbit models of myocardial ischemia-reperfusion injury, zoniporide markedly reduced infarct size without adversely affecting hemodynamics or cardiac function. In the isolated heart (Langendorff), zoniporide elicited a concentration-dependent reduction in infarct size (EC(50) = 0.25 nM). At 50 nM it reduced infarct size by 83%. This compound was 2.5-20-fold more potent than either eniporide or cariporide (EC(50)s of 0.69 and 5.11 nM, respectively), and reduced infarct size to a greater extent than eniporide. In open chest, anesthetized rabbits, zoniporide also elicited a dose-dependent reduction in infarct size (ED(50) = 0.45 mg/kg/h) and inhibited NHE-1-mediated platelet swelling (93% inhibition at 4 mg/kg/h). Furthermore, zoniporide attenuated postischemic cardiac contractile dysfunction in conscious primates, and reduced both the incidence and duration of ischemia-reperfusion-induced ventricular fibrillation in rats. Zoniporide represents a novel class of potent and selective human NHE-1 inhibitors with potential utility for providing cardioprotection in a clinical setting.
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Affiliation(s)
- W Ross Tracey
- Pfizer Global Research and Development, Groton, CT 06340, USA.
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Doggrell SA, Hancox JC. Is timing everything? Therapeutic potential of modulators of cardiac Na(+) transporters. Expert Opin Investig Drugs 2003; 12:1123-42. [PMID: 12831348 DOI: 10.1517/13543784.12.7.1123] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Sodium ion (Na(+)) transporters have roles in the modulation of cardiomyocyte pH and Na(+) and Ca(2+) handling. Activation of the cardiac Na(+)-H(+) exchanger 1 (NHE1) during ischaemia induces arrhythmias, myocardial stunning and irreversible cell injury. As the benefits of NHE1 inhibitors (e.g., amiloride, cariporide) in models of myocardial infarction are usually much greater when used as pretreatment, rather than during or after ischaemia, it is probably not surprising that clinical trials with cariporide in ischaemia have shown little shortterm benefit. NHE1 inhibitors have been shown to be beneficial in animal models of ventricular fibrillation and resuscitation, cardioplegia, hypertrophy and heart failure, and their therapeutic potential in these conditions should be further developed. The Na(+)-HCO(3)(-) cotransporter (NBC) is also stimulated by intracellular acidification, and part of the benefit of angiotensin-converting enzyme inhibitors after myocardial infarction may be due to inhibition of the NBC. Selective inhibitors of the NBC are required to determine the therapeutic potential of this mechanism. The Na(+)-Ca(2+) exchanger (NCX) has a major role in cardiac Na(+) and Ca(2+) homeostasis and influences cardiac electrical activity. The NCX also has a role in ischaemia/infarction, arrhythmias, hypertrophy and heart failure. NCX inhibitors may have beneficial effects in animal models of ischaemia and reperfusion injury and the therapeutic benefit of these should be further studied in animal models.
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Affiliation(s)
- Sheila A Doggrell
- School of Biomedical Sciences, The University of Queensland, QLD 4072, Australia.
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