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Grandits T, Augustin CM, Haase G, Jost N, Mirams GR, Niederer SA, Plank G, Varró A, Virág L, Jung A. Neural network emulation of the human ventricular cardiomyocyte action potential for more efficient computations in pharmacological studies. eLife 2024; 12:RP91911. [PMID: 38598284 PMCID: PMC11006416 DOI: 10.7554/elife.91911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/11/2024] Open
Abstract
Computer models of the human ventricular cardiomyocyte action potential (AP) have reached a level of detail and maturity that has led to an increasing number of applications in the pharmaceutical sector. However, interfacing the models with experimental data can become a significant computational burden. To mitigate the computational burden, the present study introduces a neural network (NN) that emulates the AP for given maximum conductances of selected ion channels, pumps, and exchangers. Its applicability in pharmacological studies was tested on synthetic and experimental data. The NN emulator potentially enables massive speed-ups compared to regular simulations and the forward problem (find drugged AP for pharmacological parameters defined as scaling factors of control maximum conductances) on synthetic data could be solved with average root-mean-square errors (RMSE) of 0.47 mV in normal APs and of 14.5 mV in abnormal APs exhibiting early afterdepolarizations (72.5% of the emulated APs were alining with the abnormality, and the substantial majority of the remaining APs demonstrated pronounced proximity). This demonstrates not only very fast and mostly very accurate AP emulations but also the capability of accounting for discontinuities, a major advantage over existing emulation strategies. Furthermore, the inverse problem (find pharmacological parameters for control and drugged APs through optimization) on synthetic data could be solved with high accuracy shown by a maximum RMSE of 0.22 in the estimated pharmacological parameters. However, notable mismatches were observed between pharmacological parameters estimated from experimental data and distributions obtained from the Comprehensive in vitro Proarrhythmia Assay initiative. This reveals larger inaccuracies which can be attributed particularly to the fact that small tissue preparations were studied while the emulator was trained on single cardiomyocyte data. Overall, our study highlights the potential of NN emulators as powerful tool for an increased efficiency in future quantitative systems pharmacology studies.
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Affiliation(s)
- Thomas Grandits
- Department of Mathematics and Scientific Computing, University of GrazGrazAustria
- NAWI Graz, University of GrazGrazAustria
| | - Christoph M Augustin
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging - Division of Medical Physics and Biophysics, Medical University of GrazGrazAustria
- BioTechMed-GrazGrazAustria
| | - Gundolf Haase
- Department of Mathematics and Scientific Computing, University of GrazGrazAustria
| | - Norbert Jost
- Department of Pharmacology and Pharmacotherapy, University of SzegedSzegedHungary
- HUN-REN-TKI, Research Group of PharmacologyBudapestHungary
| | - Gary R Mirams
- Centre for Mathematical Medicine & Biology, School of Mathematical Sciences, University of NottinghamNottinghamUnited Kingdom
| | - Steven A Niederer
- Division of Imaging Sciences & Biomedical Engineering, King’s College LondonLondonUnited Kingdom
| | - Gernot Plank
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging - Division of Medical Physics and Biophysics, Medical University of GrazGrazAustria
- BioTechMed-GrazGrazAustria
| | - András Varró
- Department of Pharmacology and Pharmacotherapy, University of SzegedSzegedHungary
- HUN-REN-TKI, Research Group of PharmacologyBudapestHungary
| | - László Virág
- Department of Pharmacology and Pharmacotherapy, University of SzegedSzegedHungary
| | - Alexander Jung
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging - Division of Medical Physics and Biophysics, Medical University of GrazGrazAustria
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Mohammed ASA, Mohácsi G, Naveed M, Prorok J, Jost N, Virág L, Baczkó I, Topal L, Varró A. Cellular electrophysiological effects of the citrus flavonoid hesperetin in dog and rabbit cardiac ventricular preparations. Sci Rep 2024; 14:7237. [PMID: 38538818 PMCID: PMC10973458 DOI: 10.1038/s41598-024-57828-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Accepted: 03/21/2024] [Indexed: 05/01/2024] Open
Abstract
Recent experimental data shows that hesperetin, a citrus flavonoid, affects potassium channels and can prolong the QTc interval in humans. Therefore, in the present study we investigated the effects of hesperetin on various transmembrane ionic currents and on ventricular action potentials. Transmembrane current measurements and action potential recordings were performed by patch-clamp and the conventional microelectrode techniques in dog and rabbit ventricular preparations. At 10 µM concentration hesperetin did not, however, at 30 µM significantly decreased the amplitude of the IK1, Ito, IKr potassium currents. Hesperetin at 3-30 µM significantly and in a concentration-dependent manner reduced the amplitude of the IKs current. The drug significantly decreased the amplitudes of the INaL and ICaL currents at 30 µM. Hesperetin (10 and 30 µM) did not change the action potential duration in normal preparations, however, in preparations where the repolarization reserve had been previously attenuated by 100 nM dofetilide and 1 µg/ml veratrine, caused a moderate but significant prolongation of repolarization. These results suggest that hesperetin at close to relevant concentrations inhibits the IKs outward potassium current and thereby reduces repolarization reserve. This effect in certain specific situations may prolong the QT interval and consequently may enhance proarrhythmic risk.
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Affiliation(s)
- Aiman Saleh A Mohammed
- Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi School of Medicine, University of Szeged, Szeged, Hungary
| | - Gábor Mohácsi
- Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi School of Medicine, University of Szeged, Szeged, Hungary
| | - Muhammad Naveed
- Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi School of Medicine, University of Szeged, Szeged, Hungary
| | - János Prorok
- Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi School of Medicine, University of Szeged, Szeged, Hungary
- HUN-REN-SZTE Research Group for Cardiovascular Pharmacology, Hungarian Research Network, Szeged, Hungary
| | - Norbert Jost
- Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi School of Medicine, University of Szeged, Szeged, Hungary
- HUN-REN-SZTE Research Group for Cardiovascular Pharmacology, Hungarian Research Network, Szeged, Hungary
| | - László Virág
- Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi School of Medicine, University of Szeged, Szeged, Hungary
| | - István Baczkó
- Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi School of Medicine, University of Szeged, Szeged, Hungary.
- HUN-REN-SZTE Research Group for Cardiovascular Pharmacology, Hungarian Research Network, Szeged, Hungary.
| | - Leila Topal
- Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi School of Medicine, University of Szeged, Szeged, Hungary
| | - András Varró
- Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi School of Medicine, University of Szeged, Szeged, Hungary.
- HUN-REN-SZTE Research Group for Cardiovascular Pharmacology, Hungarian Research Network, Szeged, Hungary.
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3
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Grandits T, Augustin CM, Haase G, Jost N, Mirams GR, Niederer SA, Plank G, Varró A, Virág L, Jung A. Neural network emulation of the human ventricular cardiomyocyte action potential: a tool for more efficient computation in pharmacological studies. bioRxiv 2023:2023.08.16.553497. [PMID: 38234850 PMCID: PMC10793461 DOI: 10.1101/2023.08.16.553497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2024]
Abstract
Computer models of the human ventricular cardiomyocyte action potential (AP) have reached a level of detail and maturity that has led to an increasing number of applications in the pharmaceutical sector. However, interfacing the models with experimental data can become a significant computational burden. To mitigate the computational burden, the present study introduces a neural network (NN) that emulates the AP for given maximum conductances of selected ion channels, pumps, and exchangers. Its applicability in pharmacological studies was tested on synthetic and experimental data. The NN emulator potentially enables massive speed-ups compared to regular simulations and the forward problem (find drugged AP for pharmacological parameters defined as scaling factors of control maximum conductances) on synthetic data could be solved with average root-mean-square errors (RMSE) of 0.47mV in normal APs and of 14.5mV in abnormal APs exhibiting early afterdepolarizations (72.5% of the emulated APs were alining with the abnormality, and the substantial majority of the remaining APs demonstrated pronounced proximity). This demonstrates not only very fast and mostly very accurate AP emulations but also the capability of accounting for discontinuities, a major advantage over existing emulation strategies. Furthermore, the inverse problem (find pharmacological parameters for control and drugged APs through optimization) on synthetic data could be solved with high accuracy shown by a maximum RMSE of 0.21 in the estimated pharmacological parameters. However, notable mismatches were observed between pharmacological parameters estimated from experimental data and distributions obtained from the Comprehensive in vitro Proarrhythmia Assay initiative. This reveals larger inaccuracies which can be attributed particularly to the fact that small tissue preparations were studied while the emulator was trained on single cardiomyocyte data. Overall, our study highlights the potential of NN emulators as powerful tool for an increased efficiency in future quantitative systems pharmacology studies.
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Affiliation(s)
- Thomas Grandits
- Department of Mathematics and Scientific Computing, University of Graz
- NAWI Graz, University of Graz
| | - Christoph M Augustin
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging - Division of Medical Physics and Biophysics, Medical University of Graz
- BioTechMed-Graz
| | - Gundolf Haase
- Department of Mathematics and Scientific Computing, University of Graz
| | - Norbert Jost
- Department of Pharmacology and Pharmacotherapy, University of Szeged
- HUN-REN-TKI, Research Group of Pharmacology
| | - Gary R Mirams
- Centre for Mathematical Medicine & Biology, School of Mathematical Sciences, University of Nottingham
| | - Steven A Niederer
- Division of Imaging Sciences & Biomedical Engineering, King's College London
| | - Gernot Plank
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging - Division of Medical Physics and Biophysics, Medical University of Graz
- BioTechMed-Graz
| | - András Varró
- Department of Pharmacology and Pharmacotherapy, University of Szeged
- HUN-REN-TKI, Research Group of Pharmacology
| | - László Virág
- Department of Pharmacology and Pharmacotherapy, University of Szeged
| | - Alexander Jung
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging - Division of Medical Physics and Biophysics, Medical University of Graz
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Naveed M, Mohammed ASA, Topal L, Kovács ZM, Dienes C, Ovári J, Szentandrássy N, Magyar J, Bányász T, Prorok J, Jost N, Virág L, Baczkó I, Varró A, Nánási PP, Horváth B. Selective Inhibition of Cardiac Late Na + Current Is Based on Fast Offset Kinetics of the Inhibitor. Biomedicines 2023; 11:2383. [PMID: 37760824 PMCID: PMC10525890 DOI: 10.3390/biomedicines11092383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2023] [Revised: 08/11/2023] [Accepted: 08/22/2023] [Indexed: 09/29/2023] Open
Abstract
The present study was designed to test the hypothesis that the selectivity of blocking the late Na+ current (INaL) over the peak Na+ current (INaP) is related to the fast offset kinetics of the Na+ channel inhibitor. Therefore, the effects of 1 µM GS967 (INaL inhibitor), 20 µM mexiletine (I/B antiarrhythmic) and 10 µM quinidine (I/A antiarrhythmic) on INaL and INaP were compared in canine ventricular myocardium. INaP was estimated as the maximum velocity of action potential upstroke (V+max). Equal amounts of INaL were dissected by the applied drug concentrations under APVC conditions. The inhibition of INaL by mexiletine and quinidine was comparable under a conventional voltage clamp, while both were smaller than the inhibitory effect of GS967. Under steady-state conditions, the V+max block at the physiological cycle length of 700 ms was 2.3% for GS967, 11.4% for mexiletine and 26.2% for quinidine. The respective offset time constants were 110 ± 6 ms, 456 ± 284 ms and 7.2 ± 0.9 s. These results reveal an inverse relationship between the offset time constant and the selectivity of INaL over INaP inhibition without any influence of the onset rate constant. It is concluded that the selective inhibition of INaL over INaP is related to the fast offset kinetics of the Na+ channel inhibitor.
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Affiliation(s)
- Muhammad Naveed
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, H-6720 Szeged, Hungary; (M.N.); (A.S.A.M.); (L.T.); (N.J.); (L.V.); (I.B.); (A.V.)
| | - Aiman Saleh A. Mohammed
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, H-6720 Szeged, Hungary; (M.N.); (A.S.A.M.); (L.T.); (N.J.); (L.V.); (I.B.); (A.V.)
| | - Leila Topal
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, H-6720 Szeged, Hungary; (M.N.); (A.S.A.M.); (L.T.); (N.J.); (L.V.); (I.B.); (A.V.)
| | - Zsigmond Máté Kovács
- Department of Physiology, Faculty of Medicine, University of Debrecen, H-6720 Debrecen, Hungary; (Z.M.K.); (C.D.); (J.O.); (N.S.); (J.M.); (T.B.); (B.H.)
| | - Csaba Dienes
- Department of Physiology, Faculty of Medicine, University of Debrecen, H-6720 Debrecen, Hungary; (Z.M.K.); (C.D.); (J.O.); (N.S.); (J.M.); (T.B.); (B.H.)
| | - József Ovári
- Department of Physiology, Faculty of Medicine, University of Debrecen, H-6720 Debrecen, Hungary; (Z.M.K.); (C.D.); (J.O.); (N.S.); (J.M.); (T.B.); (B.H.)
| | - Norbert Szentandrássy
- Department of Physiology, Faculty of Medicine, University of Debrecen, H-6720 Debrecen, Hungary; (Z.M.K.); (C.D.); (J.O.); (N.S.); (J.M.); (T.B.); (B.H.)
- Department of Basic Medical Sciences, Faculty of Dentistry, University of Debrecen, H-6720 Debrecen, Hungary
| | - János Magyar
- Department of Physiology, Faculty of Medicine, University of Debrecen, H-6720 Debrecen, Hungary; (Z.M.K.); (C.D.); (J.O.); (N.S.); (J.M.); (T.B.); (B.H.)
- Division of Sport Physiology, Department of Physiology, Faculty of Medicine, University of Debrecen, H-6720 Debrecen, Hungary
| | - Tamás Bányász
- Department of Physiology, Faculty of Medicine, University of Debrecen, H-6720 Debrecen, Hungary; (Z.M.K.); (C.D.); (J.O.); (N.S.); (J.M.); (T.B.); (B.H.)
| | - János Prorok
- ELKH-SZTE Research Group for Cardiovascular Pharmacology, Loránd Eötvös Research Network, 1097 Szeged, Hungary;
| | - Norbert Jost
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, H-6720 Szeged, Hungary; (M.N.); (A.S.A.M.); (L.T.); (N.J.); (L.V.); (I.B.); (A.V.)
- ELKH-SZTE Research Group for Cardiovascular Pharmacology, Loránd Eötvös Research Network, 1097 Szeged, Hungary;
| | - László Virág
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, H-6720 Szeged, Hungary; (M.N.); (A.S.A.M.); (L.T.); (N.J.); (L.V.); (I.B.); (A.V.)
| | - István Baczkó
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, H-6720 Szeged, Hungary; (M.N.); (A.S.A.M.); (L.T.); (N.J.); (L.V.); (I.B.); (A.V.)
| | - András Varró
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, H-6720 Szeged, Hungary; (M.N.); (A.S.A.M.); (L.T.); (N.J.); (L.V.); (I.B.); (A.V.)
- ELKH-SZTE Research Group for Cardiovascular Pharmacology, Loránd Eötvös Research Network, 1097 Szeged, Hungary;
| | - Péter P. Nánási
- Department of Physiology, Faculty of Medicine, University of Debrecen, H-6720 Debrecen, Hungary; (Z.M.K.); (C.D.); (J.O.); (N.S.); (J.M.); (T.B.); (B.H.)
- Division of Dental Physiology and Pharmacology, Faculty of Dentistry, University of Debrecen, H-6720 Debrecen, Hungary
| | - Balázs Horváth
- Department of Physiology, Faculty of Medicine, University of Debrecen, H-6720 Debrecen, Hungary; (Z.M.K.); (C.D.); (J.O.); (N.S.); (J.M.); (T.B.); (B.H.)
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Horváth B, Kovács ZM, Dienes C, Óvári J, Szentandrássy N, Magyar J, Bányász T, Varró A, Nánási PP. Conductance Changes of Na + Channels during the Late Na + Current Flowing under Action Potential Voltage Clamp Conditions in Canine, Rabbit, and Guinea Pig Ventricular Myocytes. Pharmaceuticals (Basel) 2023; 16:ph16040560. [PMID: 37111317 PMCID: PMC10143054 DOI: 10.3390/ph16040560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 03/22/2023] [Accepted: 03/28/2023] [Indexed: 04/29/2023] Open
Abstract
Late sodium current (INa,late) is an important inward current contributing to the plateau phase of the action potential (AP) in the mammalian heart. Although INa,late is considered as a possible target for antiarrhythmic agents, several aspects of this current remained hidden. In this work, the profile of INa,late, together with the respective conductance changes (GNa,late), were studied and compared in rabbit, canine, and guinea pig ventricular myocytes using the action potential voltage clamp (APVC) technique. In canine and rabbit myocytes, the density of INa,late was relatively stable during the plateau and decreased only along terminal repolarization of the AP, while GNa,late decreased monotonically. In contrast, INa,late increased monotonically, while GNa,late remained largely unchanged during the AP in guinea pig. The estimated slow inactivation of Na+ channels was much slower in guinea pig than in canine or rabbit myocytes. The characteristics of canine INa,late and GNa,late were not altered by using command APs recorded from rabbit or guinea pig myocytes, indicating that the different shapes of the current profiles are related to genuine interspecies differences in the gating of INa,late. Both INa,late and GNa,late decreased in canine myocytes when the intracellular Ca2+ concentration was reduced either by the extracellular application of 1 µM nisoldipine or by the intracellular application of BAPTA. Finally, a comparison of the INa,late and GNa,late profiles induced by the toxin of Anemonia sulcata (ATX-II) in canine and guinea pig myocytes revealed profound differences between the two species: in dog, the ATX-II induced INa,late and GNa,late showed kinetics similar to those observed with the native current, while in guinea pig, the ATX-II induced GNa,late increased during the AP. Our results show that there are notable interspecies differences in the gating kinetics of INa,late that cannot be explained by differences in AP morphology. These differences must be considered when interpreting the INa,late results obtained in guinea pig.
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Affiliation(s)
- Balázs Horváth
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
| | - Zsigmond M Kovács
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
| | - Csaba Dienes
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
| | - József Óvári
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
| | - Norbert Szentandrássy
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
- Department of Basic Medical Sciences, Faculty of Dentistry, University of Debrecen, 4032 Debrecen, Hungary
| | - János Magyar
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
- Division of Sport Physiology, Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
| | - Tamás Bányász
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
| | - András Varró
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, 6720 Szeged, Hungary
| | - Péter P Nánási
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
- Department of Dental Physiology and Pharmacology, Faculty of Dentistry, University of Debrecen, 4032 Debrecen, Hungary
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Polyák A, Topal L, Zombori-Tóth N, Tóth N, Prorok J, Kohajda Z, Déri S, Demeter-Haludka V, Hegyi P, Venglovecz V, Ágoston G, Husti Z, Gazdag P, Szlovák J, Árpádffy-Lovas T, Naveed M, Sarusi A, Jost N, Virág L, Nagy N, Baczkó I, Farkas AS, Varró A. Cardiac electrophysiological remodeling associated with enhanced arrhythmia susceptibility in a canine model of elite exercise. eLife 2023; 12:80710. [PMID: 36815557 PMCID: PMC10014074 DOI: 10.7554/elife.80710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 02/16/2023] [Indexed: 02/24/2023] Open
Abstract
The health benefits of regular physical exercise are well known. Even so, there is increasing evidence that the exercise regimes of elite athletes can evoke cardiac arrhythmias including ventricular fibrillation and even sudden cardiac death (SCD). The mechanism of exercise-induced arrhythmia and SCD is poorly understood. Here, we show that chronic training in a canine model (12 sedentary and 12 trained dogs) that mimics the regime of elite athletes induces electrophysiological remodeling (measured by ECG, patch-clamp, and immunocytochemical techniques) resulting in increases of both the trigger and the substrate for ventricular arrhythmias. Thus, 4 months sustained training lengthened ventricular repolarization (QTc: 237.1±3.4 ms vs. 213.6±2.8 ms, n=12; APD90: 472.8±29.6 ms vs. 370.1±32.7 ms, n=29 vs. 25), decreased transient outward potassium current (6.4±0.5 pA/pF vs. 8.8±0.9 pA/pF at 50 mV, n=54 vs. 42), and increased the short-term variability of repolarization (29.5±3.8 ms vs. 17.5±4.0 ms, n=27 vs. 18). Left ventricular fibrosis and HCN4 protein expression were also enhanced. These changes were associated with enhanced ectopic activity (number of escape beats from 0/hr to 29.7±20.3/hr) in vivo and arrhythmia susceptibility (elicited ventricular fibrillation: 3 of 10 sedentary dogs vs. 6 of 10 trained dogs). Our findings provide in vivo, cellular electrophysiological and molecular biological evidence for the enhanced susceptibility to ventricular arrhythmia in an experimental large animal model of endurance training.
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Affiliation(s)
- Alexandra Polyák
- Department of Pharmacology and Pharmacotherapy, University of SzegedSzegedHungary
| | - Leila Topal
- Department of Pharmacology and Pharmacotherapy, University of SzegedSzegedHungary
| | - Noémi Zombori-Tóth
- Department of Pharmacology and Pharmacotherapy, University of SzegedSzegedHungary
| | - Noémi Tóth
- Department of Pharmacology and Pharmacotherapy, University of SzegedSzegedHungary
| | - János Prorok
- Department of Pharmacology and Pharmacotherapy, University of SzegedSzegedHungary
- ELKH-SZTE Research Group for Cardiovascular Pharmacology, Eötvös Loránd Research NetworkSzegedHungary
| | - Zsófia Kohajda
- ELKH-SZTE Research Group for Cardiovascular Pharmacology, Eötvös Loránd Research NetworkSzegedHungary
| | - Szilvia Déri
- Department of Pharmacology and Pharmacotherapy, University of SzegedSzegedHungary
| | | | - Péter Hegyi
- Centre for Translational Medicine and Institute of Pancreatic Diseases, Semmelweis UniversityBudapestHungary
- Institute for Translational Medicine, Medical School, University of PécsPécsHungary
- Translational Pancreatology Research Group, Interdisciplinary Centre of Excellence for Research Development and Innovation, University of SzegedSzegedHungary
| | - Viktória Venglovecz
- Department of Pharmacology and Pharmacotherapy, University of SzegedSzegedHungary
| | - Gergely Ágoston
- Institute of Family Medicine, University of SzegedSzegedHungary
| | - Zoltán Husti
- Department of Pharmacology and Pharmacotherapy, University of SzegedSzegedHungary
| | - Péter Gazdag
- Department of Pharmacology and Pharmacotherapy, University of SzegedSzegedHungary
| | - Jozefina Szlovák
- Department of Pharmacology and Pharmacotherapy, University of SzegedSzegedHungary
| | - Tamás Árpádffy-Lovas
- Department of Pharmacology and Pharmacotherapy, University of SzegedSzegedHungary
| | - Muhammad Naveed
- Department of Pharmacology and Pharmacotherapy, University of SzegedSzegedHungary
| | - Annamária Sarusi
- Department of Pharmacology and Pharmacotherapy, University of SzegedSzegedHungary
| | - Norbert Jost
- Department of Pharmacology and Pharmacotherapy, University of SzegedSzegedHungary
- ELKH-SZTE Research Group for Cardiovascular Pharmacology, Eötvös Loránd Research NetworkSzegedHungary
- Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of SzegedSzegedHungary
| | - László Virág
- Department of Pharmacology and Pharmacotherapy, University of SzegedSzegedHungary
- Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of SzegedSzegedHungary
| | - Norbert Nagy
- Department of Pharmacology and Pharmacotherapy, University of SzegedSzegedHungary
- ELKH-SZTE Research Group for Cardiovascular Pharmacology, Eötvös Loránd Research NetworkSzegedHungary
| | - István Baczkó
- Department of Pharmacology and Pharmacotherapy, University of SzegedSzegedHungary
- Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of SzegedSzegedHungary
| | - Attila S Farkas
- Department of Internal Medicine, Cardiology ward, University of SzegedSzegedHungary
| | - András Varró
- Department of Pharmacology and Pharmacotherapy, University of SzegedSzegedHungary
- ELKH-SZTE Research Group for Cardiovascular Pharmacology, Eötvös Loránd Research NetworkSzegedHungary
- Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of SzegedSzegedHungary
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7
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Tóth N, Loewe A, Szlovák J, Kohajda Z, Bitay G, Levijoki J, Papp JG, Varró A, Nagy N. The reverse mode of the Na +/Ca 2+ exchanger contributes to the pacemaker mechanism in rabbit sinus node cells. Sci Rep 2022; 12:21830. [PMID: 36528651 PMCID: PMC9759562 DOI: 10.1038/s41598-022-25574-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Accepted: 12/01/2022] [Indexed: 12/23/2022] Open
Abstract
Sinus node (SN) pacemaking is based on a coupling between surface membrane ion-channels and intracellular Ca2+-handling. The fundamental role of the inward Na+/Ca2+ exchanger (NCX) is firmly established. However, little is known about the reverse mode exchange. A simulation study attributed important role to reverse NCX activity, however experimental evidence is still missing. Whole-cell and perforated patch-clamp experiments were performed on rabbit SN cells supplemented with fluorescent Ca2+-tracking. We established 2 and 8 mM pipette NaCl groups to suppress and enable reverse NCX. NCX was assessed by specific block with 1 μM ORM-10962. Mechanistic simulations were performed by Maltsev-Lakatta minimal computational SN model. Active reverse NCX resulted in larger Ca2+-transient amplitude with larger SR Ca2+-content. Spontaneous action potential (AP) frequency increased with 8 mM NaCl. When reverse NCX was facilitated by 1 μM strophantin the Ca2+i and spontaneous rate increased. ORM-10962 applied prior to strophantin prevented Ca2+i and AP cycle change. Computational simulations indicated gradually increasing reverse NCX current, Ca2+i and heart rate with increasing Na+i. Our results provide further evidence for the role of reverse NCX in SN pacemaking. The reverse NCX activity may provide additional Ca2+-influx that could increase SR Ca2+-content, which consequently leads to enhanced pacemaking activity.
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Affiliation(s)
- Noémi Tóth
- grid.9008.10000 0001 1016 9625Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi Medical School, University of Szeged, Dóm tér 12, P.O. Box 427, Szeged, 6720 Hungary
| | - Axel Loewe
- grid.7892.40000 0001 0075 5874Institute of Biomedical Engineering, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
| | - Jozefina Szlovák
- grid.9008.10000 0001 1016 9625Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi Medical School, University of Szeged, Dóm tér 12, P.O. Box 427, Szeged, 6720 Hungary
| | - Zsófia Kohajda
- ELKH-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary
| | - Gergő Bitay
- grid.9008.10000 0001 1016 9625Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi Medical School, University of Szeged, Dóm tér 12, P.O. Box 427, Szeged, 6720 Hungary
| | - Jouko Levijoki
- grid.419951.10000 0004 0400 1289Orion Pharma, Espoo, Finland
| | - Julius Gy. Papp
- grid.9008.10000 0001 1016 9625Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi Medical School, University of Szeged, Dóm tér 12, P.O. Box 427, Szeged, 6720 Hungary ,ELKH-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary
| | - András Varró
- grid.9008.10000 0001 1016 9625Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi Medical School, University of Szeged, Dóm tér 12, P.O. Box 427, Szeged, 6720 Hungary ,ELKH-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary
| | - Norbert Nagy
- grid.9008.10000 0001 1016 9625Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi Medical School, University of Szeged, Dóm tér 12, P.O. Box 427, Szeged, 6720 Hungary ,ELKH-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary
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8
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Déri S, Hartai T, Virág L, Jost N, Labro AJ, Varró A, Baczkó I, Nattel S, Ördög B. MiRP2 rescues long QT syndrome type 5. J Mol Cell Cardiol 2022. [DOI: 10.1016/j.yjmcc.2022.08.175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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9
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Topal L, Polyák A, Tóth N, Ágoston G, Bencsik P, Kohajda Z, Prorok J, Déri S, Nagy N, Jost N, Virág L, Farkas AS, Varró A, Baczkó I. Endurance training-induced cardiac remodeling in a guinea pig athlete's heart model. Can J Physiol Pharmacol 2022; 100:993-1004. [PMID: 35834825 DOI: 10.1139/cjpp-2022-0073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Besides the health benefits of regular exercise, high-level training-above an optimal level-may have adverse effects. In this study, we investigated the effects of long-term vigorous training and its potentially detrimental structural-functional changes in a small animal athlete's heart model. Thirty-eight 4-month-old male guinea pigs were randomized into sedentary and exercised groups. The latter underwent a 15-week-long endurance-training program. To investigate the effects of the intense long-term exercise, in vivo (echocardiography, electrocardiography), ex vivo, and in vitro (histopathology, patch-clamp) measurements were performed. Following the training protocol, the exercised animals exhibited structural left ventricular enlargement and a significantly higher degree of myocardial fibrosis. Furthermore, resting bradycardia accompanied by elevated heart rate variability occurred, representing increased parasympathetic activity in the exercised hearts. The observed prolonged QTc intervals and increased repolarization variability parameters may raise the risk of electrical instability in exercised animals. Complex arrhythmias did not occur in either group, and there were no differences between the groups in ex vivo or cellular electrophysiological experiments. Accordingly, the high parasympathetic activity may promote impaired repolarization in conscious exercised animals. The detected structural-functional changes share similarities with the human athlete's heart; therefore, this model might be useful for investigations on cardiac remodeling.
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Affiliation(s)
- L Topal
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, 6720, Hungary
| | - A Polyák
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, 6720, Hungary
- Department of Pediatrics and Pediatric Health Center, University of Szeged, Szeged, 6725, Hungary
| | - N Tóth
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, 6720, Hungary
| | - G Ágoston
- Institute of Family Medicine, University of Szeged, Szeged, 6720, Hungary
| | - P Bencsik
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, 6720, Hungary
| | - Zs Kohajda
- ELKH-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary
| | - J Prorok
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, 6720, Hungary
- ELKH-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary
| | - Sz Déri
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, 6720, Hungary
| | - N Nagy
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, 6720, Hungary
- ELKH-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary
| | - N Jost
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, 6720, Hungary
- ELKH-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary
- Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged, 6720, Hungary
| | - L Virág
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, 6720, Hungary
- Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged, 6720, Hungary
| | - A S Farkas
- Department of Internal Medicine, Cardiology, University of Szeged, Szeged, 6725, Hungary
| | - A Varró
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, 6720, Hungary
- ELKH-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary
- Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged, 6720, Hungary
| | - I Baczkó
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, 6720, Hungary
- Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged, 6720, Hungary
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10
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Árpádffy-Lovas T, Naveed M, Mohammed ASA, Virág L, Baczkó I, Varró A. Species dependent cardiac electrophysiological effects elicited by various potassium channel blocking drugs. J Gen Physiol 2022. [PMID: 34766973 DOI: 10.1085/jgp.2021ecc2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Rodents are commonly used as models in electrophysiology. However, distinct differences exist between large animals and rodents in terms of their ion channel expression and action potential shapes, possibly limiting the translational value of findings obtained in rodents. We aimed for a direct comparison of the possible impact of selective inhibition of ion channels on the cardiac repolarization in preparations from human hearts and from model species. We applied the standard microelectrode technique at 37°C on cardiac ventricular preparations (papillary muscles and trabecules) from human (n = 63), dog (n = 47), guinea pig (n = 53), rat (n = 43), and rabbit (n = 16) hearts, paced at 1 Hz. To selectively block the IKur current, 1 µM XEN-D101; IK1 current, 10 µM barium chloride; IKr current, 50 nM dofetilide; IKs current, 500 nM HMR-1556; and Ito current, 100 µM chromanol-293B were applied directly to the tissue bath. The block of IKur and IK1 elicited significantly more prominent prolongation of APD in rats (35.6% and 67.9%, respectively) when compared with the other species, including that of human (1.0% and 2.6%, respectively). On the other hand, IKr block did not affect APD in rat preparations (1.6%), whereas it elicited marked prolongation in other species (9.0-47.7%), especially being pronounced in human preparations (60.3%). IKs inhibition elicited similar but minor APD prolongation (0.3-11.4%) in all species. Inhibition of Ito moderately lengthened APD in dog (22.3%) and rabbit (17.5%) preparations but elicited no change of APD in human preparations. In contrast, block of Ito caused marked APD prolongation in rat preparations (33.2%). Our findings suggest that the specific inhibition of various ion channels elicits fundamentally different effects in rodent ventricular action potential when compared with those of other species, including human. Therefore, from a translational standpoint, rodent models in cardiac electrophysiological and arrhythmia research should be used with great caution.
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Affiliation(s)
- Tamás Árpádffy-Lovas
- Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi Medical School, University of Szeged, Szeged, Hungary
| | - Muhammad Naveed
- Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi Medical School, University of Szeged, Szeged, Hungary
| | - Aiman Saleh A Mohammed
- Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi Medical School, University of Szeged, Szeged, Hungary
| | - László Virág
- Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi Medical School, University of Szeged, Szeged, Hungary
| | - István Baczkó
- Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi Medical School, University of Szeged, Szeged, Hungary
| | - András Varró
- Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi Medical School, University of Szeged, Szeged, Hungary.,ELKH-SZTE Research Group of Cardiovascular Pharmacology, University of Szeged, Szeged, Hungary
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11
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Árpádffy-Lovas T, Mohammed ASA, Naveed M, Koncz I, Baláti B, Bitay M, Jost N, Nagy N, Baczkó I, Virág L, Varró A. Species dependent differences in the inhibition of various potassium currents and in their effects on repolarization in cardiac ventricular muscle. Can J Physiol Pharmacol 2022; 100:880-889. [PMID: 35442802 DOI: 10.1139/cjpp-2022-0028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Even though rodents are accessible model animals, their electrophysiological properties are deeply different from that of human, making the translation of rat studies to human rather difficult. We compared the mechanisms of ventricular repolarization in various animal models to those of human by measuring cardiac ventricular action potentials from ventricular papillary muscle preparations using conventional microelectrodes, and applying selective inhibitors of various potassium transmembrane ion currents. Inhibition of the IK1 current (10 µM barium chloride) significantly prolonged rat ventricular repolarization, but only slightly prolonged it in dog, and did not affect it in human. On the contrary, IKr inhibition (50 nM dofetilide) significantly prolonged repolarization in human, rabbit, and dog, but not in rat. Inhibition of the IKur current (1 µM XEN-D0101) only prolonged rat ventricular repolarization, and had no effect in human or dog. Inhibition of the IKs (500 nM HMR-1556) and Ito currents (100 µM chromanol-293B) elicited similar effects in all investigated species. We conclude that dog ventricular preparations have the strongest, and rat ventricular preparations have the weakest translational value in cardiac electrophysiological experiments.
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Affiliation(s)
- Tamás Árpádffy-Lovas
- University of Szeged Albert Szent-Györgyi Faculty of Medicine, 37443, Department of Pharmacology and Pharmacotherapy, Szeged, Csongrád, Hungary;
| | - Aiman Saleh A Mohammed
- University of Szeged Albert Szent-Györgyi Faculty of Medicine, 37443, Department of Pharmacology and Pharmacotherapy, Szeged, Csongrád, Hungary;
| | - Muhammad Naveed
- University of Szeged Albert Szent-Györgyi Faculty of Medicine, 37443, Department of Pharmacology and Pharmacotherapy, Szeged, Csongrád, Hungary;
| | - István Koncz
- University of Szeged Albert Szent-Györgyi Faculty of Medicine, 37443, Department of Pharmacology and Pharmacotherapy, Szeged, Csongrád, Hungary;
| | - Beáta Baláti
- University of Szeged Albert Szent-Györgyi Faculty of Medicine, 37443, Department of Pharmacology and Pharmacotherapy, Szeged, Csongrád, Hungary;
| | - Miklós Bitay
- University of Szeged Albert Szent-Györgyi Faculty of Medicine, 37443, Department of Cardiac Surgery, Second Department of Internal Medicine and Cardiology Center, Szeged, Csongrád, Hungary;
| | - Norbert Jost
- University of Szeged Albert Szent-Györgyi Faculty of Medicine, 37443, Department of Pharmacology and Pharmacotherapy, Szeged, Csongrád, Hungary.,Eötvös Loránd Research Network, 579839, ELKH-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary, Budapest, Hungary;
| | - Norbert Nagy
- University of Szeged Albert Szent-Györgyi Faculty of Medicine, 37443, Department of Pharmacology and Pharamacotherapy, Szeged, Csongrád, Hungary.,Eötvös Loránd Research Network, 579839, ELKH-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary, Budapest, Hungary;
| | - István Baczkó
- University of Szeged Albert Szent-Györgyi Faculty of Medicine, 37443, Department of Pharmacology and Pharmacotherapy, Szeged, Csongrád, Hungary;
| | - László Virág
- University of Szeged Albert Szent-Györgyi Faculty of Medicine, 37443, Department of Pharmacology and Pharmacotherapy, Szeged, Csongrád, Hungary;
| | - András Varró
- University of Szeged Albert Szent-Györgyi Faculty of Medicine, 37443, Department of Pharmacology and Pharmacotherapy, Szeged, Csongrád, Hungary.,Eötvös Loránd Research Network, 579839, ELKH-SZTE Research Group of Cardiovascular Pharmacology, Budapest, Hungary;
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12
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Kui P, Polyák A, Morvay N, Tiszlavicz L, Nagy N, Ördög B, Takács H, Leprán I, Farkas A, Papp JG, Jost N, Varró A, Baczkó I, Farkas AS. Long-Term Endurance Exercise Training Alters Repolarization in a New Rabbit Athlete’s Heart Model. Front Physiol 2022; 12:741317. [PMID: 35237176 PMCID: PMC8882986 DOI: 10.3389/fphys.2021.741317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Accepted: 10/22/2021] [Indexed: 11/13/2022] Open
Abstract
In the present study, the effect of long-term exercise training was investigated on myocardial morphological and functional remodeling and on proarrhythmic sensitivity in a rabbit athlete’s heart model. New-Zealand white rabbits were trained during a 12-week long treadmill running protocol and compared with their sedentary controls. At the end of the training protocol, echocardiography, in vivo and in vitro ECG recordings, proarrhythmic sensitivity with dofetilide (nM) were performed in isolated hearts, and action potential duration (APD) measurements at different potassium concentrations (4.5 and 2 mM) were made in the isolated papillary muscles. Expression levels of the slow component of delayed rectifier potassium current and fibrosis synthesis and degradation biomarkers were quantified. Echocardiography showed a significantly dilated left ventricle in the running rabbits. ECG PQ and RR intervals were significantly longer in the exercised group (79 ± 2 vs. 69 ± 2 ms and 325 ± 11 vs. 265 ± 6 ms, p < 0.05, respectively). The in vivo heart rate variability (HRV) (SD of root mean square: 5.2 ± 1.4 ms vs. 1.4 ± 0.2 ms, p < 0.05) and Tpeak-Tend variability were higher in the running rabbits. Bradycardia disappeared in the exercised group in vitro. Dofetilide tended to increase the QTc interval in a greater extent, and significantly increased the number of arrhythmic beats in the trained animals in vitro. APD was longer in the exercised group at a low potassium level. Real-time quantitative PCR (RT-qPCR) showed significantly greater messenger RNA expression of fibrotic biomarkers in the exercised group. Increased repolarization variability and higher arrhythmia incidences, lengthened APD at a low potassium level, increased fibrotic biomarker gene expressions may indicate higher sensitivity of the rabbit “athlete’s heart” to life-threatening arrhythmias.
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Affiliation(s)
- Péter Kui
- Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi Medical School, University of Szeged, Szeged, Hungary
| | - Alexandra Polyák
- Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi Medical School, University of Szeged, Szeged, Hungary
- Department of Internal Medicine, Albert Szent-Györgyi Medical School, University of Szeged, Szeged, Hungary
- ELKH-SZTE Working Group of Cardiovascular Pharmacology, Szeged, Hungary
| | - Nikolett Morvay
- Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi Medical School, University of Szeged, Szeged, Hungary
| | - László Tiszlavicz
- Department of Pathology, Albert Szent-Györgyi Medical School, University of Szeged, Szeged, Hungary
| | - Norbert Nagy
- Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi Medical School, University of Szeged, Szeged, Hungary
- ELKH-SZTE Working Group of Cardiovascular Pharmacology, Szeged, Hungary
| | - Balázs Ördög
- Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi Medical School, University of Szeged, Szeged, Hungary
| | - Hedvig Takács
- Department of Internal Medicine, Albert Szent-Györgyi Medical School, University of Szeged, Szeged, Hungary
| | - István Leprán
- Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi Medical School, University of Szeged, Szeged, Hungary
| | - András Farkas
- Department of Internal Medicine, Albert Szent-Györgyi Medical School, University of Szeged, Szeged, Hungary
| | - Julius Gy. Papp
- Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi Medical School, University of Szeged, Szeged, Hungary
- ELKH-SZTE Working Group of Cardiovascular Pharmacology, Szeged, Hungary
| | - Norbert Jost
- Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi Medical School, University of Szeged, Szeged, Hungary
- ELKH-SZTE Working Group of Cardiovascular Pharmacology, Szeged, Hungary
| | - András Varró
- Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi Medical School, University of Szeged, Szeged, Hungary
- ELKH-SZTE Working Group of Cardiovascular Pharmacology, Szeged, Hungary
- Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, Albert Szent-Györgyi Medical School, University of Szeged, Szeged, Hungary
- *Correspondence: András Varró,
| | - István Baczkó
- Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi Medical School, University of Szeged, Szeged, Hungary
- Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, Albert Szent-Györgyi Medical School, University of Szeged, Szeged, Hungary
| | - Attila S. Farkas
- Department of Internal Medicine, Albert Szent-Györgyi Medical School, University of Szeged, Szeged, Hungary
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13
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Kohajda Z, Virág L, Hornyik T, Husti Z, Sztojkov-Ivanov A, Nagy N, Horváth A, Varga R, Prorok J, Szlovák J, Tóth N, Gazdag P, Topal L, Naveed M, Árpádffy-Lovas T, Pászti B, Magyar T, Koncz I, Déri S, Demeter-Haludka V, Aigner Z, Ördög B, Patfalusi M, Tálosi L, Tiszlavicz L, Földesi I, Jost N, Baczkó I, Varró A. In vivo and cellular antiarrhythmic and cardiac electrophysiological effects of desethylamiodarone in dog cardiac preparations. Br J Pharmacol 2022; 179:3382-3402. [PMID: 35106755 DOI: 10.1111/bph.15812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 01/13/2022] [Accepted: 01/17/2022] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND AND PURPOSE The aim of the present study was to study the antiarrhythmic effects and cellular mechanisms of desethylamiodarone (DEA), the main metabolite of amiodarone (AMIO), following acute and chronic 4-week oral treatments (25-50 mg·kg-1 ·day-1 ). EXPERIMENTAL APPROACH The antiarrhythmic effects of acute iv. (10 mg·kg-1 ) and chronic oral (4 weeks, 25 mg·kg-1 ·day-1 ) administration of DEA were assessed in carbachol and tachypacing-induced dog atrial fibrillation models. Action potentials were recorded from atrial and right ventricular tissue following acute (10 μM) and chronic (p.o. 4 weeks, 50 mg·kg-1 ·day-1 ) DEA application using the conventional microelectrode technique. Ionic currents were measured by the whole cell configuration of the patch clamp technique in isolated left ventricular myocytes. Pharmacokinetic studies were performed following a single intravenous dose (25 mg·kg-1 ) of AMIO and DEA intravenously and orally. In chronic (91-day) toxicological investigations, DEA and AMIO were administered in the oral dose of 25 mg·kg-1 ·day-1 ). KEY RESULTS DEA exerted marked antiarrhythmic effects in both canine atrial fibrillation models. Both acute and chronic DEA administration prolonged action potential duration in atrial and ventricular muscle without any changes detected in Purkinje fibres. DEA decreased the amplitude of several outward potassium currents such as IKr , IKs , IK1 , Ito , and IKACh , while the ICaL and late INa inward currents were also significantly depressed. Better drug bioavailability and higher volume of distribution for DEA were observed compared to AMIO. No neutropenia and less severe pulmonary fibrosis was found following DEA compared to that of AMIO administration. CONCLUSION AND IMPLICATIONS Chronic DEA treatment in animal experiments has marked antiarrhythmic and electrophysiological effects with better pharmacokinetics and lower toxicity than its parent compound. These results suggest that the active metabolite, DEA, should be considered for clinical trials as a possible new, more favourable option for the treatment of cardiac arrhythmias including atrial fibrillation.
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Affiliation(s)
- Zsófia Kohajda
- ELKH-SZTE Research Group for Cardiovascular Pharmacology, Eötvös Loránd Research Network, Szeged, Hungary
| | - László Virág
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged, Hungary
| | - Tibor Hornyik
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - Zoltán Husti
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - Anita Sztojkov-Ivanov
- Department of Pharmacodynamics and Biopharmacy, University of Szeged, Szeged, Hungary
| | - Norbert Nagy
- ELKH-SZTE Research Group for Cardiovascular Pharmacology, Eötvös Loránd Research Network, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - András Horváth
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - Richárd Varga
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - János Prorok
- ELKH-SZTE Research Group for Cardiovascular Pharmacology, Eötvös Loránd Research Network, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - Jozefina Szlovák
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - Noémi Tóth
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - Péter Gazdag
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - Leila Topal
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - Muhammad Naveed
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - Tamás Árpádffy-Lovas
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - Bence Pászti
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - Tibor Magyar
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - István Koncz
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - Szilvia Déri
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| | | | - Zoltán Aigner
- Institute of Pharmaceutical Technology and Regulatory Affairs, University of Szeged, Szeged, Hungary
| | - Balázs Ördög
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - Márta Patfalusi
- Department of Toxicology, ATRC Aurigon Toxicological Research Center Ltd., Dunakeszi, Hungary
| | - László Tálosi
- Department of Pharmacognosy, Faculty of Pharmacy, University of Szeged, Szeged, Hungary
| | - László Tiszlavicz
- Department of Pathology, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Imre Földesi
- Department of Laboratory Medicine, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Norbert Jost
- ELKH-SZTE Research Group for Cardiovascular Pharmacology, Eötvös Loránd Research Network, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged, Hungary
| | - István Baczkó
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged, Hungary
| | - András Varró
- ELKH-SZTE Research Group for Cardiovascular Pharmacology, Eötvös Loránd Research Network, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged, Hungary
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14
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Abstract
Chronic heart failure is a clinical syndrome with multiple etiologies, associated with significant morbidity and mortality. Cardiac arrhythmias, including ventricular tachyarrhythmias and atrial fibrillation, are common in heart failure. A number of cardiac diseases including heart failure alter the expression and regulation of ion channels and transporters leading to arrhythmogenic electrical remodeling. Myocardial hypertrophy, fibrosis and scar formation are key elements of arrhythmogenic structural remodeling in heart failure. In this article, the mechanisms responsible for increased arrhythmia susceptibility as well as the underlying changes in ion channel, transporter expression and function as well as alterations in calcium handling in heart failure are discussed. Understanding the mechanisms of arrhythmogenic remodeling is key to improving arrhythmia management and the prevention of sudden cardiac death in patients with heart failure.
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Affiliation(s)
- Zoltán Husti
- Department of Pharmacology and Pharmacotherapy, University of Szeged, 6720 Szeged, Hungary; (Z.H.); (A.V.)
- Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, 6720 Szeged, Hungary
| | - András Varró
- Department of Pharmacology and Pharmacotherapy, University of Szeged, 6720 Szeged, Hungary; (Z.H.); (A.V.)
- Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, 6720 Szeged, Hungary
- ELKH-SZTE Research Group for Cardiovascular Pharmacology, Eötvös Loránd Research Network, 6720 Szeged, Hungary
| | - István Baczkó
- Department of Pharmacology and Pharmacotherapy, University of Szeged, 6720 Szeged, Hungary; (Z.H.); (A.V.)
- Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, 6720 Szeged, Hungary
- Correspondence:
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15
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Kiss D, Horváth B, Hézső T, Dienes C, Kovács Z, Topal L, Szentandrássy N, Almássy J, Prorok J, Virág L, Bányász T, Varró A, Nánási PP, Magyar J. Late Na + Current Is [Ca 2+] i-Dependent in Canine Ventricular Myocytes. Pharmaceuticals (Basel) 2021; 14:ph14111142. [PMID: 34832924 PMCID: PMC8623624 DOI: 10.3390/ph14111142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 10/27/2021] [Accepted: 11/02/2021] [Indexed: 11/16/2022] Open
Abstract
Enhancement of the late sodium current (INaL) increases arrhythmia propensity in the heart, whereas suppression of the current is antiarrhythmic. In the present study, we investigated INaL in canine ventricular cardiomyocytes under action potential voltage-clamp conditions using the selective Na+ channel inhibitors GS967 and tetrodotoxin. Both 1 µM GS967 and 10 µM tetrodotoxin dissected largely similar inward currents. The amplitude and integral of the GS967-sensitive current was significantly smaller after the reduction of intracellular Ca2+ concentration ([Ca2+]i) either by superfusion of the cells with 1 µM nisoldipine or by intracellular application of 10 mM BAPTA. Inhibiting calcium/calmodulin-dependent protein kinase II (CaMKII) by KN-93 or the autocamtide-2-related inhibitor peptide similarly reduced the amplitude and integral of INaL. Action potential duration was shortened in a reverse rate-dependent manner and the plateau potential was depressed by GS967. This GS967-induced depression of plateau was reduced by pretreatment of the cells with BAPTA-AM. We conclude that (1) INaL depends on the magnitude of [Ca2+]i in canine ventricular cells, (2) this [Ca2+]i-dependence of INaL is mediated by the Ca2+-dependent activation of CaMKII, and (3) INaL is augmented by the baseline CaMKII activity.
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Affiliation(s)
- Dénes Kiss
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (D.K.); (B.H.); (T.H.); (C.D.); (Z.K.); (N.S.); (J.A.); (T.B.); (J.M.)
| | - Balázs Horváth
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (D.K.); (B.H.); (T.H.); (C.D.); (Z.K.); (N.S.); (J.A.); (T.B.); (J.M.)
- Faculty of Pharmacy, University of Debrecen, 4032 Debrecen, Hungary
| | - Tamás Hézső
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (D.K.); (B.H.); (T.H.); (C.D.); (Z.K.); (N.S.); (J.A.); (T.B.); (J.M.)
| | - Csaba Dienes
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (D.K.); (B.H.); (T.H.); (C.D.); (Z.K.); (N.S.); (J.A.); (T.B.); (J.M.)
| | - Zsigmond Kovács
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (D.K.); (B.H.); (T.H.); (C.D.); (Z.K.); (N.S.); (J.A.); (T.B.); (J.M.)
| | - Leila Topal
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, 6725 Szeged, Hungary; (L.T.); (J.P.); (L.V.); (A.V.)
| | - Norbert Szentandrássy
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (D.K.); (B.H.); (T.H.); (C.D.); (Z.K.); (N.S.); (J.A.); (T.B.); (J.M.)
- Department of Basic Medical Sciences, Faculty of Dentistry, University of Debrecen, 4032 Debrecen, Hungary
| | - János Almássy
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (D.K.); (B.H.); (T.H.); (C.D.); (Z.K.); (N.S.); (J.A.); (T.B.); (J.M.)
| | - János Prorok
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, 6725 Szeged, Hungary; (L.T.); (J.P.); (L.V.); (A.V.)
- ELKH-SZTE Research Group for Cardiovascular Pharmacology, Eötvös Loránd Research Network, 6725 Szeged, Hungary
| | - László Virág
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, 6725 Szeged, Hungary; (L.T.); (J.P.); (L.V.); (A.V.)
- Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, 6725 Szeged, Hungary
| | - Tamás Bányász
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (D.K.); (B.H.); (T.H.); (C.D.); (Z.K.); (N.S.); (J.A.); (T.B.); (J.M.)
| | - András Varró
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, 6725 Szeged, Hungary; (L.T.); (J.P.); (L.V.); (A.V.)
- ELKH-SZTE Research Group for Cardiovascular Pharmacology, Eötvös Loránd Research Network, 6725 Szeged, Hungary
- Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, 6725 Szeged, Hungary
| | - Péter P. Nánási
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (D.K.); (B.H.); (T.H.); (C.D.); (Z.K.); (N.S.); (J.A.); (T.B.); (J.M.)
- Department of Dental Physiology and Pharmacology, Faculty of Dentistry, University of Debrecen, 4032 Debrecen, Hungary
- Correspondence: ; Tel.: +36-52255575; Fax: +36-52255116
| | - János Magyar
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (D.K.); (B.H.); (T.H.); (C.D.); (Z.K.); (N.S.); (J.A.); (T.B.); (J.M.)
- Division of Sport Physiology, Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
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16
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Tóth N, Soós A, Váradi A, Hegyi P, Tinusz B, Vágvölgyi A, Orosz A, Solymár M, Polyák A, Varró A, Farkas AS, Nagy N. Effect of ivabradine in heart failure: a meta-analysis of heart failure patients with reduced versus preserved ejection fraction. Can J Physiol Pharmacol 2021; 99:1159-1174. [PMID: 34636643 DOI: 10.1139/cjpp-2020-0700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In clinical trials of heart failure reduced ejection fraction (HFrEF), ivabradine seemed to be an effective heart rate lowering agent associated with lower risk of cardiovascular death. In contrast, ivabradine failed to improve cardiovascular outcomes in heart failure preserved ejection fraction (HFpEF) despite the significant effect on heart rate. This meta-analysis is the first to compare the effects of ivabradine on heart rate and mortality parameters in HFpEF versus HFrEF. We screened three databases: PubMed, Embase, and Cochrane Library. The outcomes of these studies were mortality, reduction in heart rate, and left ventricular function improvement. We compared the efficacy of ivabradine treatment in HFpEF versus HFrEF. Heart rate analysis of pooled data showed decrease in both HFrEF (-17.646 beats/min) and HFpEF (-11.434 beats/min), and a tendency to have stronger bradycardic effect in HFrEF (p = 0.094) in randomized clinical trials. Left ventricular ejection fraction analysis revealed significant improvement in HFrEF (5.936, 95% CI: [4.199-7.672], p < 0.001) when compared with placebo (p < 0.001). We found that ivabradine significantly improves left ventricular performance in HFrEF, at the same time it exerts a tendency to have improved bradycardic effect in HFrEF. These disparate effects of ivabradine and the higher prevalence of non-cardiac comorbidities in HFpEF may explain the observed beneficial effects in HFrEF and the unchanged outcomes in HFpEF patients after ivabradine treatment.
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Affiliation(s)
- Noémi Tóth
- Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi Medical School University of Szeged, Dóm Square 12, Szeged 6720, Hungary
| | - Alexandra Soós
- Institute for Translational Medicine, Medical School, University of Pécs, 12 Szigeti Street, Pécs 7624, Hungary
| | - Alex Váradi
- Institute for Translational Medicine, Medical School, University of Pécs, 12 Szigeti Street, Pécs 7624, Hungary
| | - Péter Hegyi
- Institute for Translational Medicine, Medical School, University of Pécs, 12 Szigeti Street, Pécs 7624, Hungary
| | - Benedek Tinusz
- Institute for Translational Medicine, Medical School, University of Pécs, 12 Szigeti Street, Pécs 7624, Hungary.,First Department of Medicine, Medical School, University of Pécs, Ifjúság Street 13, Pécs 7624, Hungary
| | - Anna Vágvölgyi
- Department of Internal Medicine, Albert Szent-Györgyi Medical School University of Szeged, Kálvária sgt. 57, Szeged 6720, Hungary
| | - Andrea Orosz
- Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi Medical School University of Szeged, Dóm Square 12, Szeged 6720, Hungary
| | - Margit Solymár
- Institute for Translational Medicine, Medical School, University of Pécs, 12 Szigeti Street, Pécs 7624, Hungary
| | - Alexandra Polyák
- Department of Internal Medicine, Albert Szent-Györgyi Medical School University of Szeged, Kálvária sgt. 57, Szeged 6720, Hungary
| | - András Varró
- Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi Medical School University of Szeged, Dóm Square 12, Szeged 6720, Hungary.,ELKH-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary
| | - Attila S Farkas
- Department of Internal Medicine, Albert Szent-Györgyi Medical School University of Szeged, Kálvária sgt. 57, Szeged 6720, Hungary
| | - Norbert Nagy
- Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi Medical School University of Szeged, Dóm Square 12, Szeged 6720, Hungary.,ELKH-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary
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17
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Castiglione A, Hornyik T, Wülfers EM, Giammarino L, Edler I, Jowais JJ, Rieder M, Perez-Feliz S, Koren G, Bősze Z, Varró A, Zehender M, Brunner M, Bode C, Liin SI, Larsson HP, Baczkó I, Odening KE. Docosahexaenoic acid normalizes QT interval in long QT type 2 transgenic rabbit models in a genotype-specific fashion. Europace 2021; 24:511-522. [PMID: 34601592 DOI: 10.1093/europace/euab228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 08/11/2021] [Indexed: 11/13/2022] Open
Abstract
AIM Long QT syndrome (LQTS) is a cardiac channelopathy predisposing to ventricular arrhythmias and sudden cardiac death. Since current therapies often fail to prevent arrhythmic events in certain LQTS subtypes, new therapeutic strategies are needed. Docosahexaenoic acid (DHA) is a polyunsaturated fatty acid, which enhances the repolarizing IKs current. METHODS AND RESULTS We investigated the effects of DHA in wild type (WT) and transgenic long QT Type 1 (LQT1; loss of IKs), LQT2 (loss of IKr), LQT5 (reduction of IKs), and LQT2-5 (loss of IKr and reduction of IKs) rabbits. In vivo ECGs were recorded at baseline and after 10 µM/kg DHA to assess changes in heart-rate corrected QT (QTc) and short-term variability of QT (STVQT). Ex vivo monophasic action potentials were recorded in Langendorff-perfused rabbit hearts, and action potential duration (APD75) and triangulation were assessed. Docosahexaenoic acid significantly shortened QTc in vivo only in WT and LQT2 rabbits, in which both α- and β-subunits of IKs-conducting channels are functionally intact. In LQT2, this led to a normalization of QTc and of its short-term variability. Docosahexaenoic acid had no effect on QTc in LQT1, LQT5, and LQT2-5. Similarly, ex vivo, DHA shortened APD75 in WT and normalized it in LQT2, and additionally decreased AP triangulation in LQT2. CONCLUSIONS Docosahexaenoic acid exerts a genotype-specific beneficial shortening/normalizing effect on QTc and APD75 and reduces pro-arrhythmia markers STVQT and AP triangulation through activation of IKs in LQT2 rabbits but has no effects if either α- or β-subunits to IKs are functionally impaired. Docosahexaenoic acid could represent a new genotype-specific therapy in LQT2.
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Affiliation(s)
- Alessandro Castiglione
- Department of Cardiology and Angiology I, University Heart Center Freiburg, Medical Faculty, University of Freiburg, Freiburg, Germany.,Translational Cardiology, Department of Cardiology, Inselspital, Bern University Hospital, University of Bern, Buehlplatz 5, CH-3012 Bern, Switzerland.,Department of Translational Cardiology/Electrophysiology, Institute of Physiology, University of Bern, Bern, Switzerland
| | - Tibor Hornyik
- Department of Cardiology and Angiology I, University Heart Center Freiburg, Medical Faculty, University of Freiburg, Freiburg, Germany.,Translational Cardiology, Department of Cardiology, Inselspital, Bern University Hospital, University of Bern, Buehlplatz 5, CH-3012 Bern, Switzerland.,Department of Translational Cardiology/Electrophysiology, Institute of Physiology, University of Bern, Bern, Switzerland.,Institute of Experimental Cardiovascular Medicine, University Heart Center Freiburg-Bad Krozingen, Medical Faculty, University of Freiburg, Freiburg, Germany.,Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - Eike M Wülfers
- Institute of Experimental Cardiovascular Medicine, University Heart Center Freiburg-Bad Krozingen, Medical Faculty, University of Freiburg, Freiburg, Germany
| | - Lucilla Giammarino
- Translational Cardiology, Department of Cardiology, Inselspital, Bern University Hospital, University of Bern, Buehlplatz 5, CH-3012 Bern, Switzerland.,Department of Translational Cardiology/Electrophysiology, Institute of Physiology, University of Bern, Bern, Switzerland
| | - Iask Edler
- Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Jessica J Jowais
- Department of Physiology and Biophysics, University of Miami, Miami, FL, USA
| | - Marina Rieder
- Department of Cardiology and Angiology I, University Heart Center Freiburg, Medical Faculty, University of Freiburg, Freiburg, Germany.,Translational Cardiology, Department of Cardiology, Inselspital, Bern University Hospital, University of Bern, Buehlplatz 5, CH-3012 Bern, Switzerland.,Department of Translational Cardiology/Electrophysiology, Institute of Physiology, University of Bern, Bern, Switzerland
| | - Stefanie Perez-Feliz
- Department of Cardiology and Angiology I, University Heart Center Freiburg, Medical Faculty, University of Freiburg, Freiburg, Germany.,Institute of Experimental Cardiovascular Medicine, University Heart Center Freiburg-Bad Krozingen, Medical Faculty, University of Freiburg, Freiburg, Germany
| | - Gideon Koren
- Division of Cardiology, Cardiovascular Research Center, Brown University, Providence, RI, USA
| | - Zsuzsanna Bősze
- Animal Biotechnology Department, NARIC Agricultural Biotechnology Institute, Gödöllő, Hungary
| | - András Varró
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - Manfred Zehender
- Department of Cardiology and Angiology I, University Heart Center Freiburg, Medical Faculty, University of Freiburg, Freiburg, Germany
| | - Michael Brunner
- Department of Cardiology and Angiology I, University Heart Center Freiburg, Medical Faculty, University of Freiburg, Freiburg, Germany.,Department of Cardiology and Medical Intensive Care, St. Josefskrankenhaus, Freiburg, Germany
| | - Christoph Bode
- Department of Cardiology and Angiology I, University Heart Center Freiburg, Medical Faculty, University of Freiburg, Freiburg, Germany
| | - Sara I Liin
- Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Hans Peter Larsson
- Department of Physiology and Biophysics, University of Miami, Miami, FL, USA
| | - István Baczkó
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - Katja E Odening
- Department of Cardiology and Angiology I, University Heart Center Freiburg, Medical Faculty, University of Freiburg, Freiburg, Germany.,Translational Cardiology, Department of Cardiology, Inselspital, Bern University Hospital, University of Bern, Buehlplatz 5, CH-3012 Bern, Switzerland.,Department of Translational Cardiology/Electrophysiology, Institute of Physiology, University of Bern, Bern, Switzerland
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18
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Tóth N, Szlovák J, Kohajda Z, Bitay G, Veress R, Horváth B, Papp JG, Varró A, Nagy N. The development of L-type Ca 2+ current mediated alternans does not depend on the restitution slope in canine ventricular myocardium. Sci Rep 2021; 11:16652. [PMID: 34404848 PMCID: PMC8371021 DOI: 10.1038/s41598-021-95299-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Accepted: 07/23/2021] [Indexed: 11/25/2022] Open
Abstract
Cardiac alternans have crucial importance in the onset of ventricular fibrillation. The early explanation for alternans development was the voltage-driven mechanism, where the action potential (AP) restitution steepness was considered as crucial determining factor. Recent results suggest that restitution slope is an inadequate predictor for alternans development, but several studies still claim the role of membrane potential as underlying mechanism of alternans. These controversial data indicate that the relationship of restitution and alternans development is not completely understood. APs were measured by conventional microelectrode technique from canine right ventricular papillary muscles. Ionic currents combined with fluorescent measurements were recorded by patch-clamp technique. APs combined with fluorescent measurements were monitored by sharp microelectrodes. Rapid pacing evoked restitution-independent AP duration (APD) alternans. When non-alternating AP voltage command was used, Ca2+i-transient (CaT) alternans were not observed. When alternating rectangular voltage pulses were applied, CaT alternans were proportional to ICaL amplitude alternans. Selective ICaL inhibition did not influence the fast phase of APD restitution. In this study we found that ICaL has minor contribution in shaping the fast phase of restitution curve suggesting that ICaL—if it plays important role in the alternans mechanism—could be an additional factor that attenuates the reliability of APD restitution slope to predict alternans.
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Affiliation(s)
- Noémi Tóth
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Dóm tér 12, P.O. Box 427, 6720, Szeged, Hungary
| | - Jozefina Szlovák
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Dóm tér 12, P.O. Box 427, 6720, Szeged, Hungary
| | - Zsófia Kohajda
- ELKH-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary
| | - Gergő Bitay
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Dóm tér 12, P.O. Box 427, 6720, Szeged, Hungary
| | - Roland Veress
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Balázs Horváth
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary.,Faculty of Pharmacy, University of Debrecen, Debrecen, Hungary
| | - Julius Gy Papp
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Dóm tér 12, P.O. Box 427, 6720, Szeged, Hungary.,ELKH-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary
| | - András Varró
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Dóm tér 12, P.O. Box 427, 6720, Szeged, Hungary.,ELKH-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged, Hungary
| | - Norbert Nagy
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Dóm tér 12, P.O. Box 427, 6720, Szeged, Hungary. .,ELKH-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary.
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19
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Déri S, Borbás J, Hartai T, Hategan L, Csányi B, Visnyovszki Á, Madácsy T, Maléth J, Hegedűs Z, Nagy I, Arora R, Labro AJ, Környei L, Varró A, Sepp R, Ördög B. Impaired cytoplasmic domain interactions cause co-assembly defect and loss of function in the p.Glu293Lys KNCJ2 variant isolated from an Andersen-Tawil syndrome patient. Cardiovasc Res 2021; 117:1923-1934. [PMID: 32810216 DOI: 10.1093/cvr/cvaa249] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 07/16/2020] [Accepted: 08/12/2020] [Indexed: 02/07/2023] Open
Abstract
AIMS Subunit interactions at the cytoplasmic domain interface (CD-I) have recently been shown to control gating in inward rectifier potassium channels. Here we report the novel KCNJ2 variant p.Glu293Lys that has been found in a patient with Andersen-Tawil syndrome type 1 (ATS1), causing amino acid substitution at the CD-I of the inward rectifier potassium channel subunit Kir2.1. Neither has the role of Glu293 in gating control been investigated nor has a pathogenic variant been described at this position. This study aimed to assess the involvement of Glu293 in CD-I subunit interactions and to establish the pathogenic role of the p.Glu293Lys variant in ATS1. METHODS AND RESULTS The p.Glu293Lys variant produced no current in homomeric form and showed dominant-negative effect over wild-type (WT) subunits. Immunocytochemical labelling showed the p.Glu293Lys subunits to distribute in the subsarcolemmal space. Salt bridge prediction indicated the presence of an intersubunit salt bridge network at the CD-I of Kir2.1, with the involvement of Glu293. Subunit interactions were studied by the NanoLuc® Binary Technology (NanoBiT) split reporter assay. Reporter constructs carrying NanoBiT tags on the intracellular termini produced no bioluminescent signal above background with the p.Glu293Lys variant in homomeric configuration and significantly reduced signals in cells co-expressing WT and p.Glu293Lys subunits simultaneously. Extracellularly presented reporter tags, however, generated comparable bioluminescent signals with heteromeric WT and p.Glu293Lys subunits and with homomeric WT channels. CONCLUSIONS Loss of function and dominant-negative effect confirm the causative role of p.Glu293Lys in ATS1. Co-assembly of Kir2.1 subunits is impaired in homomeric channels consisting of p.Glu293Lys subunits and is partially rescued in heteromeric complexes of WT and p.Glu293Lys Kir2.1 variants. These data point to an important role of Glu293 in mediating subunit assembly, as well as in gating of Kir2.1 channels.
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Affiliation(s)
- Szilvia Déri
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Dóm tér 12, PO Box 427, Szeged 6720, Hungary
- Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Dóm tér 12, 6720 Szeged, Hungary
| | - János Borbás
- 2nd Department of Internal Medicine and Cardiology Centre, University of Szeged, Semmelweis u. 8, 6725 Szeged, Hungary
| | - Teodóra Hartai
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Dóm tér 12, PO Box 427, Szeged 6720, Hungary
| | - Lidia Hategan
- 2nd Department of Internal Medicine and Cardiology Centre, University of Szeged, Semmelweis u. 8, 6725 Szeged, Hungary
| | - Beáta Csányi
- 2nd Department of Internal Medicine and Cardiology Centre, University of Szeged, Semmelweis u. 8, 6725 Szeged, Hungary
| | - Ádám Visnyovszki
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Dóm tér 12, PO Box 427, Szeged 6720, Hungary
| | - Tamara Madácsy
- 1st Department of Internal Medicine, University of Szeged, Korányi fasor 8-10, 6720 Szeged, Hungary, Hungary
| | - József Maléth
- 1st Department of Internal Medicine, University of Szeged, Korányi fasor 8-10, 6720 Szeged, Hungary, Hungary
| | - Zoltán Hegedűs
- Institute of Biophysics, Biological Research Centre of the Hungarian Academy of Sciences, Temesvári krt. 62, 6726 Szeged, Hungary
- Department of Biochemistry and Medical Chemistry, University of Pécs, Szigeti út 12, 7624 Pécs, Hungary
| | - István Nagy
- Institute of Biochemistry, Biological Research Centre the Hungarian Academy of Sciences, Temesvári krt. 62, 6726 Szeged, Hungary
- Seqomics Biotechnology Ltd, Vállalkozók útja 7, 6782 Mórahalom, Hungary
| | - Rohit Arora
- Department of Veterinary Sciences, University of Antwerp, Universiteitsplein 1, 2610 Antwerp, Belgium
| | - Alain J Labro
- Department of Biomedical Sciences, University of Antwerp, Universiteitsplein 1, 2610 Antwerp, Belgium
- Department of Basic Medical Sciences, University of Ghent, C. Heymanslaan 10, 9000 Ghent, Belgium
| | - László Környei
- Gottsegen György National Institute of Cardiology, Haller u. 9, 1096 Budapest, Hungary
| | - András Varró
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Dóm tér 12, PO Box 427, Szeged 6720, Hungary
- Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Dóm tér 12, 6720 Szeged, Hungary
- MTA-SZTE Research Group for Cardiovascular Pharmacology, Hungarian Academy of Sciences, Dóm tér 12, 6720 Szeged, Hungary
| | - Róbert Sepp
- 2nd Department of Internal Medicine and Cardiology Centre, University of Szeged, Semmelweis u. 8, 6725 Szeged, Hungary
| | - Balázs Ördög
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Dóm tér 12, PO Box 427, Szeged 6720, Hungary
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20
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Hézső T, Naveed M, Dienes C, Kiss D, Prorok J, Árpádffy-Lovas T, Varga R, Fujii E, Mercan T, Topal L, Kistamás K, Szentandrássy N, Almássy J, Jost N, Magyar J, Bányász T, Baczkó I, Varró A, Nánási PP, Virág L, Horváth B. Mexiletine-like cellular electrophysiological effects of GS967 in canine ventricular myocardium. Sci Rep 2021; 11:9565. [PMID: 33953276 PMCID: PMC8100105 DOI: 10.1038/s41598-021-88903-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 03/26/2021] [Indexed: 12/14/2022] Open
Abstract
Enhancement of the late Na+ current (INaL) increases arrhythmia propensity in the heart, while suppression of the current is antiarrhythmic. GS967 is an agent considered as a selective blocker of INaL. In the present study, effects of GS967 on INaL and action potential (AP) morphology were studied in canine ventricular myocytes by using conventional voltage clamp, action potential voltage clamp and sharp microelectrode techniques. The effects of GS967 (1 µM) were compared to those of the class I/B antiarrhythmic compound mexiletine (40 µM). Under conventional voltage clamp conditions, INaL was significantly suppressed by GS967 and mexiletine, causing 80.4 ± 2.2% and 59.1 ± 1.8% reduction of the densities of INaL measured at 50 ms of depolarization, and 79.0 ± 3.1% and 63.3 ± 2.7% reduction of the corresponding current integrals, respectively. Both drugs shifted the voltage dependence of the steady-state inactivation curve of INaL towards negative potentials. GS967 and mexiletine dissected inward INaL profiles under AP voltage clamp conditions having densities, measured at 50% of AP duration (APD), of −0.37 ± 0.07 and −0.28 ± 0.03 A/F, and current integrals of −56.7 ± 9.1 and −46.6 ± 5.5 mC/F, respectively. Drug effects on peak Na+ current (INaP) were assessed by recording the maximum velocity of AP upstroke (V+max) in multicellular preparations. The offset time constant was threefold faster for GS967 than mexiletine (110 ms versus 289 ms), while the onset of the rate-dependent block was slower in the case of GS967. Effects on beat-to-beat variability of APD was studied in isolated myocytes. Beat-to-beat variability was significantly decreased by both GS967 and mexiletine (reduction of 42.1 ± 6.5% and 24.6 ± 12.8%, respectively) while their shortening effect on APD was comparable. It is concluded that the electrophysiological effects of GS967 are similar to those of mexiletine, but with somewhat faster offset kinetics of V+max block. However, since GS967 depressed V+max and INaL at the same concentration, the current view that GS967 represents a new class of drugs that selectively block INaL has to be questioned and it is suggested that GS967 should be classified as a class I/B antiarrhythmic agent.
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Affiliation(s)
- Tamás Hézső
- Department of Physiology, Faculty of Medicine, University of Debrecen, Nagyerdei krt 98, 4012, Debrecen, Hungary
| | - Muhammad Naveed
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Dóm tér 12, 6701, Szeged, Hungary
| | - Csaba Dienes
- Department of Physiology, Faculty of Medicine, University of Debrecen, Nagyerdei krt 98, 4012, Debrecen, Hungary
| | - Dénes Kiss
- Department of Physiology, Faculty of Medicine, University of Debrecen, Nagyerdei krt 98, 4012, Debrecen, Hungary
| | - János Prorok
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Dóm tér 12, 6701, Szeged, Hungary.,MTA-SZTE Research Group for Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary
| | - Tamás Árpádffy-Lovas
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Dóm tér 12, 6701, Szeged, Hungary
| | - Richárd Varga
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Dóm tér 12, 6701, Szeged, Hungary
| | - Erika Fujii
- Department of Physiology, Faculty of Medicine, University of Debrecen, Nagyerdei krt 98, 4012, Debrecen, Hungary
| | - Tanju Mercan
- Department of Biophysics, School of Medicine, Akdeniz University, Antalya, Turkey
| | - Leila Topal
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Dóm tér 12, 6701, Szeged, Hungary
| | - Kornél Kistamás
- Department of Physiology, Faculty of Medicine, University of Debrecen, Nagyerdei krt 98, 4012, Debrecen, Hungary
| | - Norbert Szentandrássy
- Department of Physiology, Faculty of Medicine, University of Debrecen, Nagyerdei krt 98, 4012, Debrecen, Hungary.,Department of Basic Medical Sciences, Faculty of Dentistry, University of Debrecen, Debrecen, Hungary
| | - János Almássy
- Department of Physiology, Faculty of Medicine, University of Debrecen, Nagyerdei krt 98, 4012, Debrecen, Hungary
| | - Norbert Jost
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Dóm tér 12, 6701, Szeged, Hungary.,MTA-SZTE Research Group for Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary
| | - János Magyar
- Department of Physiology, Faculty of Medicine, University of Debrecen, Nagyerdei krt 98, 4012, Debrecen, Hungary.,Division of Sport Physiology, Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Tamás Bányász
- Department of Physiology, Faculty of Medicine, University of Debrecen, Nagyerdei krt 98, 4012, Debrecen, Hungary
| | - István Baczkó
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Dóm tér 12, 6701, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged, Hungary
| | - András Varró
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Dóm tér 12, 6701, Szeged, Hungary. .,MTA-SZTE Research Group for Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary. .,Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged, Hungary.
| | - Péter P Nánási
- Department of Physiology, Faculty of Medicine, University of Debrecen, Nagyerdei krt 98, 4012, Debrecen, Hungary. .,Department of Dental Physiology and Pharmacology, Faculty of Dentistry, University of Debrecen, Debrecen, Hungary.
| | - László Virág
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Dóm tér 12, 6701, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged, Hungary
| | - Balázs Horváth
- Department of Physiology, Faculty of Medicine, University of Debrecen, Nagyerdei krt 98, 4012, Debrecen, Hungary.,Faculty of Pharmacy, University of Debrecen, Debrecen, Hungary
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21
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Szlovák J, Tomek J, Zhou X, Tóth N, Veress R, Horváth B, Szentandrássy N, Levijoki J, Papp JG, Herring N, Varró A, Eisner DA, Rodriguez B, Nagy N. Blockade of sodium‑calcium exchanger via ORM-10962 attenuates cardiac alternans. J Mol Cell Cardiol 2021; 153:111-122. [PMID: 33383036 PMCID: PMC8035081 DOI: 10.1016/j.yjmcc.2020.12.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2020] [Revised: 12/08/2020] [Accepted: 12/21/2020] [Indexed: 12/27/2022]
Abstract
Repolarization alternans, a periodic oscillation of long-short action potential duration, is an important source of arrhythmogenic substrate, although the mechanisms driving it are insufficiently understood. Despite its relevance as an arrhythmia precursor, there are no successful therapies able to target it specifically. We hypothesized that blockade of the sodium‑calcium exchanger (NCX) could inhibit alternans. The effects of the selective NCX blocker ORM-10962 were evaluated on action potentials measured with microelectrodes from canine papillary muscle preparations, and calcium transients measured using Fluo4-AM from isolated ventricular myocytes paced to evoke alternans. Computer simulations were used to obtain insight into the drug's mechanisms of action. ORM-10962 attenuated cardiac alternans, both in action potential duration and calcium transient amplitude. Three morphological types of alternans were observed, with differential response to ORM-10962 with regards to APD alternans attenuation. Analysis of APD restitution indicates that calcium oscillations underlie alternans formation. Furthermore, ORM-10962 did not markedly alter APD restitution, but increased post-repolarization refractoriness, which may be mediated by indirectly reduced L-type calcium current. Computer simulations reproduced alternans attenuation via ORM-10962, suggesting that it is acts by reducing sarcoplasmic reticulum release refractoriness. This results from the ORM-10962-induced sodium‑calcium exchanger block accompanied by an indirect reduction in L-type calcium current. Using a computer model of a heart failure cell, we furthermore demonstrate that the anti-alternans effect holds also for this disease, in which the risk of alternans is elevated. Targeting NCX may therefore be a useful anti-arrhythmic strategy to specifically prevent calcium driven alternans.
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Affiliation(s)
- Jozefina Szlovák
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary
| | - Jakub Tomek
- Department of Physiology, Anatomy, and Genetics, University of Oxford, United Kingdom; Department of Computer Science, University of Oxford, United Kingdom.
| | - Xin Zhou
- Department of Computer Science, University of Oxford, United Kingdom
| | - Noémi Tóth
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary
| | - Roland Veress
- Department of Physiology, Faculty of Medicine, University of Debrecen, Hungary
| | - Balázs Horváth
- Department of Physiology, Faculty of Medicine, University of Debrecen, Hungary; Faculty of Pharmacy, University of Debrecen, Hungary
| | | | | | - Julius Gy Papp
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary; MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary
| | - Neil Herring
- Department of Physiology, Anatomy, and Genetics, University of Oxford, United Kingdom
| | - András Varró
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary; MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary
| | - David A Eisner
- Unit of Cardiac Physiology, Manchester Academic Health Science Centre, University of Manchester, Core Technology Facility, Manchester, UK
| | - Blanca Rodriguez
- Department of Computer Science, University of Oxford, United Kingdom
| | - Norbert Nagy
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary; MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary
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22
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Biliczki P, Boon RA, Girmatsion Z, Bukowska A, Ördög B, Kaess BM, Hohnloser SH, Goette A, Varró A, Moritz A, Nattel S, Ehrlich JR. Age-related regulation and region-specific distribution of ion channel subunits promoting atrial fibrillation in human left and right atria. Europace 2020; 21:1261-1269. [PMID: 31131392 DOI: 10.1093/europace/euz135] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2018] [Accepted: 04/23/2019] [Indexed: 12/13/2022] Open
Abstract
AIMS Age-induced changes and electrical remodelling are important components of the atrial fibrillation (AF) substrate. To study regional distribution and age-dependent changes in gene expression that may promote AF in human atria. METHODS AND RESULTS Human left atrial (LA) and right atrial (RA) tissue samples were obtained from donor hearts unsuitable for transplantation and from patients undergoing mitral valve repair. Atrial fibrillation was mimicked in vitro by tachypacing of human atrial tissue slices. Ionic currents were studied by the whole-cell patch-clamp technique; gene expression was analysed by real-time qPCR and immunoblotting. Both healthy RA and RA from older patients showed greater CACNA1c mRNA and CaV1.2 protein expression than LA. No age-dependent changes of Kir2.1 expression in both atria were seen. Remodelling occurred in a qualitatively similar manner in RA and LA. IK1 and Kir2.1 protein expression increased with AF. MiR-1, miR-26a, and miR-26b were down-regulated with AF in both atria. ICa,L was decreased. CACNA1c and CACNA2b expression decreased and miR-328 increased in RA and LA during AF. Ex vivo tachypacing of human atrial slices replicated these findings. There were age-dependent increases in miR-1 and miR-328, while miR-26a decreased with age in atrial tissues from healthy human donor hearts. CONCLUSION Features of electrical remodelling in man occur in a qualitatively similar manner in both human atria. Age-related miR-328 dysregulation and reduced ICa,L may contribute to increased AF susceptibility with age.
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Affiliation(s)
- Peter Biliczki
- Division of Cardiology, St.Josefs-Hospital, Beethovenstr. 20, Wiesbaden, Germany.,Division of Cardiology, Goethe-University, Frankfurt, Germany
| | - Reinier A Boon
- Institute for Cardiovascular Regeneration, Goethe-University, Frankfurt, Germany
| | | | - Alicia Bukowska
- Molekularpharmakologische Elektrophysiologie, Universitätsklinikum, Magdeburg, Germany
| | - Balázs Ördög
- Institute of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - Bernhard M Kaess
- Division of Cardiology, St.Josefs-Hospital, Beethovenstr. 20, Wiesbaden, Germany
| | | | - Andreas Goette
- Molekularpharmakologische Elektrophysiologie, Universitätsklinikum, Magdeburg, Germany
| | - András Varró
- Institute of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - Anton Moritz
- Cardiothoracic Surgery, Goethe-University, Frankfurt, Germany
| | - Stanley Nattel
- Research Center, Montreal Heart Institute and University of Montreal, Montreal, Canada
| | - Joachim R Ehrlich
- Division of Cardiology, St.Josefs-Hospital, Beethovenstr. 20, Wiesbaden, Germany.,Division of Cardiology, Goethe-University, Frankfurt, Germany
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23
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Varró A, Tomek J, Nagy N, Virág L, Passini E, Rodriguez B, Baczkó I. Cardiac transmembrane ion channels and action potentials: cellular physiology and arrhythmogenic behavior. Physiol Rev 2020; 101:1083-1176. [PMID: 33118864 DOI: 10.1152/physrev.00024.2019] [Citation(s) in RCA: 67] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Cardiac arrhythmias are among the leading causes of mortality. They often arise from alterations in the electrophysiological properties of cardiac cells and their underlying ionic mechanisms. It is therefore critical to further unravel the pathophysiology of the ionic basis of human cardiac electrophysiology in health and disease. In the first part of this review, current knowledge on the differences in ion channel expression and properties of the ionic processes that determine the morphology and properties of cardiac action potentials and calcium dynamics from cardiomyocytes in different regions of the heart are described. Then the cellular mechanisms promoting arrhythmias in congenital or acquired conditions of ion channel function (electrical remodeling) are discussed. The focus is on human-relevant findings obtained with clinical, experimental, and computational studies, given that interspecies differences make the extrapolation from animal experiments to human clinical settings difficult. Deepening the understanding of the diverse pathophysiology of human cellular electrophysiology will help in developing novel and effective antiarrhythmic strategies for specific subpopulations and disease conditions.
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Affiliation(s)
- András Varró
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary.,MTA-SZTE Cardiovascular Pharmacology Research Group, Hungarian Academy of Sciences, Szeged, Hungary
| | - Jakub Tomek
- Department of Computer Science, British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Norbert Nagy
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary.,MTA-SZTE Cardiovascular Pharmacology Research Group, Hungarian Academy of Sciences, Szeged, Hungary
| | - László Virág
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Elisa Passini
- Department of Computer Science, British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Blanca Rodriguez
- Department of Computer Science, British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, United Kingdom
| | - István Baczkó
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
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24
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Erőss B, Molnár Z, Szakács Z, Zádori N, Szakó L, Váncsa S, Juhász MF, Ocskay K, Vörhendi N, Márta K, Szentesi A, Párniczky A, Hegyi PJ, Kiss S, Földi M, Dembrovszky F, Kanjo A, Pázmány P, Varró A, Csathó Á, Helyes Z, Péterfi Z, Czopf L, Kiss I, Zemplényi A, Czapári D, Hegyi E, Dobszai D, Miklós E, Márta A, Tóth D, Farkas R, Farkas N, Birkás B, Pintér E, Pethő G, Zsigmond B, Sárközi A, Nagy A, Hegyi P. Personalised health education against health damage of COVID-19 epidemic in the elderly Hungarian population (PROACTIVE-19): protocol of an adaptive randomised controlled clinical trial. Trials 2020; 21:809. [PMID: 32993779 PMCID: PMC7522906 DOI: 10.1186/s13063-020-04733-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 09/08/2020] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND Early reports indicate that COVID-19 may require intensive care unit (ICU) admission in 5-26% and overall mortality can rise to 11% of the recognised cases, particularly affecting the elderly. There is a lack of evidence-based targeted pharmacological therapy for its prevention and treatment. We aim to compare the effects of a World Health Organization recommendation-based education and a personalised complex preventive lifestyle intervention package (based on the same WHO recommendation) on the outcomes of the COVID-19. METHODS PROACTIVE-19 is a pragmatic, randomised controlled clinical trial with adaptive "sample size re-estimation" design. Hungarian population over the age of 60 years without confirmed COVID-19 will be approached to participate in a telephone health assessment and lifestyle counselling voluntarily. Volunteers will be randomised into two groups: (A) general health education and (B) personalised health education. Participants will go through questioning and recommendation in 5 fields: (1) mental health, (2) smoking habits, (3) physical activity, (4) dietary habits, and (5) alcohol consumption. Both groups A and B will receive the same line of questioning to assess habits concerning these topics. Assessment will be done weekly during the first month, every second week in the second month, then monthly. The composite primary endpoint will include the rate of ICU admission, hospital admission (longer than 48 h), and mortality in COVID-19-positive cases. The estimated sample size is 3788 subjects per study arm. The planned duration of the follow-up is a minimum of 1 year. DISCUSSION These interventions may boost the body's cardiovascular and pulmonary reserve capacities, leading to improved resistance against the damage caused by COVID-19. Consequently, lifestyle changes can reduce the incidence of life-threatening conditions and attenuate the detrimental effects of the pandemic seriously affecting the older population. TRIAL REGISTRATION The study has been approved by the Scientific and Research Ethics Committee of the Hungarian Medical Research Council (IV/2428- 2 /2020/EKU) and has been registered at clinicaltrials.gov ( NCT04321928 ) on 25 March 2020.
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Affiliation(s)
- Bálint Erőss
- Institute for Translational Medicine, Medical School, University of Pécs, Szigeti út 12, Pécs, H-7624 Hungary
- Translational Medicine Foundation, Szeged, Hungary
| | - Zsolt Molnár
- Institute for Translational Medicine, Medical School, University of Pécs, Szigeti út 12, Pécs, H-7624 Hungary
- Department of Anaesthesiology and Intensive Therapy, Poznan University for Medical Sciences, Poznan, Poland
| | - Zsolt Szakács
- Institute for Translational Medicine, Medical School, University of Pécs, Szigeti út 12, Pécs, H-7624 Hungary
- János Szentágothai Research Centre, University of Pécs, Pécs, Hungary
| | - Noémi Zádori
- Institute for Translational Medicine, Medical School, University of Pécs, Szigeti út 12, Pécs, H-7624 Hungary
- János Szentágothai Research Centre, University of Pécs, Pécs, Hungary
| | - Lajos Szakó
- Institute for Translational Medicine, Medical School, University of Pécs, Szigeti út 12, Pécs, H-7624 Hungary
- János Szentágothai Research Centre, University of Pécs, Pécs, Hungary
| | - Szilárd Váncsa
- Institute for Translational Medicine, Medical School, University of Pécs, Szigeti út 12, Pécs, H-7624 Hungary
- János Szentágothai Research Centre, University of Pécs, Pécs, Hungary
| | - Márk Félix Juhász
- Institute for Translational Medicine, Medical School, University of Pécs, Szigeti út 12, Pécs, H-7624 Hungary
- János Szentágothai Research Centre, University of Pécs, Pécs, Hungary
| | - Klementina Ocskay
- Institute for Translational Medicine, Medical School, University of Pécs, Szigeti út 12, Pécs, H-7624 Hungary
- János Szentágothai Research Centre, University of Pécs, Pécs, Hungary
| | - Nóra Vörhendi
- Institute for Translational Medicine, Medical School, University of Pécs, Szigeti út 12, Pécs, H-7624 Hungary
- János Szentágothai Research Centre, University of Pécs, Pécs, Hungary
| | - Katalin Márta
- Institute for Translational Medicine, Medical School, University of Pécs, Szigeti út 12, Pécs, H-7624 Hungary
- János Szentágothai Research Centre, University of Pécs, Pécs, Hungary
| | - Andrea Szentesi
- Institute for Translational Medicine, Medical School, University of Pécs, Szigeti út 12, Pécs, H-7624 Hungary
- Translational Medicine Foundation, Szeged, Hungary
- Centre for Translational Medicine, Department of Medicine, University of Szeged, Szeged, Hungary
| | - Andrea Párniczky
- Institute for Translational Medicine, Medical School, University of Pécs, Szigeti út 12, Pécs, H-7624 Hungary
- Heim Pál National Pediatric Institute, Budapest, Hungary
| | - Péter J. Hegyi
- Institute for Translational Medicine, Medical School, University of Pécs, Szigeti út 12, Pécs, H-7624 Hungary
- János Szentágothai Research Centre, University of Pécs, Pécs, Hungary
| | - Szabolcs Kiss
- Institute for Translational Medicine, Medical School, University of Pécs, Szigeti út 12, Pécs, H-7624 Hungary
- János Szentágothai Research Centre, University of Pécs, Pécs, Hungary
- Centre for Translational Medicine, Department of Medicine, University of Szeged, Szeged, Hungary
- Doctoral School of Clinical Medicine, University of Szeged, Szeged, Hungary
| | - Mária Földi
- Institute for Translational Medicine, Medical School, University of Pécs, Szigeti út 12, Pécs, H-7624 Hungary
- János Szentágothai Research Centre, University of Pécs, Pécs, Hungary
- Centre for Translational Medicine, Department of Medicine, University of Szeged, Szeged, Hungary
- Doctoral School of Clinical Medicine, University of Szeged, Szeged, Hungary
| | - Fanni Dembrovszky
- Institute for Translational Medicine, Medical School, University of Pécs, Szigeti út 12, Pécs, H-7624 Hungary
- János Szentágothai Research Centre, University of Pécs, Pécs, Hungary
| | - Anna Kanjo
- Institute for Translational Medicine, Medical School, University of Pécs, Szigeti út 12, Pécs, H-7624 Hungary
- János Szentágothai Research Centre, University of Pécs, Pécs, Hungary
- Heim Pál National Pediatric Institute, Budapest, Hungary
| | - Piroska Pázmány
- Institute for Translational Medicine, Medical School, University of Pécs, Szigeti út 12, Pécs, H-7624 Hungary
- János Szentágothai Research Centre, University of Pécs, Pécs, Hungary
- Heim Pál National Pediatric Institute, Budapest, Hungary
| | - András Varró
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - Árpád Csathó
- Department of Behavioral Sciences, Medical School, University of Pécs, Pécs, Hungary
| | - Zsuzsanna Helyes
- János Szentágothai Research Centre, University of Pécs, Pécs, Hungary
- Department of Pharmacology and Pharmacotherapy, Medical School, University of Pécs, Pécs, Hungary
| | - Zoltán Péterfi
- Division of Infectious Diseases, 1st Department of Medicine, Medical School, University of Pécs, Pécs, Hungary
| | - László Czopf
- Division of Cardiology, First Department of Medicine, Medical School, University of Pécs, Pécs, Hungary
| | - István Kiss
- Department of Public Health, Medical School, University of Pécs, Pécs, Hungary
| | - Antal Zemplényi
- Health Technology Assessment Center, University of Pécs, Pécs, Hungary
- Division of Pharmacoeconomics, Department of Pharmaceutics, Faculty of Pharmacy, University of Pécs, Pécs, Hungary
| | - Dóra Czapári
- Institute for Translational Medicine, Medical School, University of Pécs, Szigeti út 12, Pécs, H-7624 Hungary
| | - Eszter Hegyi
- Institute for Translational Medicine, Medical School, University of Pécs, Szigeti út 12, Pécs, H-7624 Hungary
- Faculty of Law, University of Szeged, Szeged, Hungary
| | - Dalma Dobszai
- Institute for Translational Medicine, Medical School, University of Pécs, Szigeti út 12, Pécs, H-7624 Hungary
| | - Emőke Miklós
- Institute for Translational Medicine, Medical School, University of Pécs, Szigeti út 12, Pécs, H-7624 Hungary
| | - Attila Márta
- Institute for Translational Medicine, Medical School, University of Pécs, Szigeti út 12, Pécs, H-7624 Hungary
| | - Dominika Tóth
- Institute for Translational Medicine, Medical School, University of Pécs, Szigeti út 12, Pécs, H-7624 Hungary
| | - Richard Farkas
- Institute for Translational Medicine, Medical School, University of Pécs, Szigeti út 12, Pécs, H-7624 Hungary
| | - Nelli Farkas
- Institute for Translational Medicine, Medical School, University of Pécs, Szigeti út 12, Pécs, H-7624 Hungary
- Institute Bioanalysis, Medical School, University of Pécs, Pécs, Hungary
| | - Béla Birkás
- Department of Behavioral Sciences, Medical School, University of Pécs, Pécs, Hungary
| | - Erika Pintér
- János Szentágothai Research Centre, University of Pécs, Pécs, Hungary
- Department of Pharmacology and Pharmacotherapy, Medical School, University of Pécs, Pécs, Hungary
| | - Gábor Pethő
- János Szentágothai Research Centre, University of Pécs, Pécs, Hungary
- Department of Pharmacology and Pharmacotherapy, Medical School, University of Pécs, Pécs, Hungary
| | | | - Andrea Sárközi
- Heim Pál National Pediatric Institute, Budapest, Hungary
| | - Anikó Nagy
- Heim Pál National Pediatric Institute, Budapest, Hungary
| | - Péter Hegyi
- Institute for Translational Medicine, Medical School, University of Pécs, Szigeti út 12, Pécs, H-7624 Hungary
- Translational Medicine Foundation, Szeged, Hungary
- János Szentágothai Research Centre, University of Pécs, Pécs, Hungary
- Centre for Translational Medicine, Department of Medicine, University of Szeged, Szeged, Hungary
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Varga RS, Hornyik T, Husti Z, Kohajda Z, Krajsovszky G, Nagy N, Jost N, Virág L, Tálosi L, Mátyus P, Varró A, Baczkó I. Antiarrhythmic and cardiac electrophysiological effects of SZV-270, a novel compound with combined Class I/B and Class III effects, in rabbits and dogs. Can J Physiol Pharmacol 2020; 99:89-101. [PMID: 32970956 DOI: 10.1139/cjpp-2020-0412] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Cardiovascular diseases are the leading causes of mortality. Sudden cardiac death is most commonly caused by ventricular fibrillation (VF). Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia and a major cause of stroke and heart failure. Pharmacological management of VF and AF remains suboptimal due to limited efficacy of antiarrhythmic drugs and their ventricular proarrhythmic adverse effects. In this study, the antiarrhythmic and cardiac cellular electrophysiological effects of SZV-270, a novel compound, were investigated in rabbit and canine models. SZV-270 significantly reduced the incidence of VF in rabbits subjected to coronary artery occlusion/reperfusion and reduced the incidence of burst-induced AF in a tachypaced conscious canine model of AF. SZV-270 prolonged the frequency-corrected QT interval, lengthened action potential duration and effective refractory period in ventricular and atrial preparations, blocked I Kr in isolated cardiomyocytes (Class III effects), and reduced the maximum rate of depolarization (V max) at cycle lengths smaller than 1000 ms in ventricular preparations (Class I/B effect). Importantly, SZV-270 did not provoke Torsades de Pointes arrhythmia in an anesthetized rabbit proarrhythmia model characterized by impaired repolarization reserve. In conclusion, SZV-270 with its combined Class I/B and III effects can prevent reentry arrhythmias with reduced risk of provoking drug-induced Torsades de Pointes.
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Affiliation(s)
- Richárd S Varga
- Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged, Hungary
| | - Tibor Hornyik
- Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged, Hungary
| | - Zoltán Husti
- Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged, Hungary
| | - Zsófia Kohajda
- MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary
| | - Gábor Krajsovszky
- Department of Organic Chemistry, Semmelweis University, Budapest, Hungary
| | - Norbert Nagy
- MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary
| | - Norbert Jost
- Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged, Hungary
| | - László Virág
- Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged, Hungary
| | - László Tálosi
- Department of Pharmacognosy, Faculty of Pharmacy, University of Szeged, Szeged, Hungary
| | - Péter Mátyus
- Department of Organic Chemistry, Semmelweis University, Budapest, Hungary
| | - András Varró
- Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged, Hungary.,MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary
| | - István Baczkó
- Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged, Hungary
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Otsomaa L, Levijoki J, Wohlfahrt G, Chapman H, Koivisto AP, Syrjänen K, Koskelainen T, Peltokorpi SE, Finckenberg P, Heikkilä A, Abi-Gerges N, Ghetti A, Miller PE, Page G, Mervaala E, Nagy N, Kohajda Z, Jost N, Virág L, Varró A, Papp JG. Discovery and characterization of ORM-11372, a novel inhibitor of the sodium-calcium exchanger with positive inotropic activity. Br J Pharmacol 2020; 177:5534-5554. [PMID: 32959887 PMCID: PMC7707092 DOI: 10.1111/bph.15257] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 08/14/2020] [Accepted: 09/03/2020] [Indexed: 11/29/2022] Open
Abstract
Background and Purpose The lack of selective sodium–calcium exchanger (NCX) inhibitors has hampered the exploration of physiological and pathophysiological roles of cardiac NCX 1.1. We aimed to discover more potent and selective drug like NCX 1.1 inhibitor. Experimental Approach A flavan series‐based pharmacophore model was constructed. Virtual screening helped us identify a novel scaffold for NCX inhibition. A distinctively different NCX 1.1 inhibitor, ORM‐11372, was discovered after lead optimization. Its potency against human and rat NCX 1.1 and selectivity against other ion channels was assessed. The cardiovascular effects of ORM‐11372 were studied in normal and infarcted rats and rabbits. Human cardiac safety was studied ex vivo using human ventricular trabeculae. Key Results ORM‐11372 inhibited human NCX 1.1 reverse and forward currents; IC50 values were 5 and 6 nM respectively. ORM‐11372 inhibited human cardiac sodium 1.5 (INa) and hERG KV11.1 currents (IhERG) in a concentration‐dependent manner; IC50 values were 23.2 and 10.0 μM. ORM‐11372 caused no changes in action potential duration; short‐term variability and triangulation were observed for concentrations of up to 10 μM. ORM‐11372 induced positive inotropic effects of 18 ± 6% and 35 ± 8% in anaesthetized rats with myocardial infarctions and in healthy rabbits respectively; no other haemodynamic effects were observed, except improved relaxation at the lowest dose. Conclusion and Implications ORM‐11372, a unique, novel, and potent inhibitor of human and rat NCX 1.1, is a positive inotropic compound. NCX inhibition can induce clinically relevant improvements in left ventricular contractions without affecting relaxation, heart rate, or BP, without pro‐arrhythmic risk.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Piet Finckenberg
- Department of Pharmacology, Faculty of Medicine, Helsinki, Finland
| | | | | | | | | | - Guy Page
- R&D, AnaBios Corporation, San Diego, CA, USA
| | - Eero Mervaala
- Department of Pharmacology, Faculty of Medicine, Helsinki, Finland
| | - Norbert Nagy
- MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Zsófia Kohajda
- MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary
| | - Norbert Jost
- MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - László Virág
- Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - András Varró
- MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Julius Gy Papp
- MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, Faculty of Medicine, University of Szeged, Szeged, Hungary
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27
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Pászti B, Prorok J, Magyar T, Árpádffy-Lovas T, Györe B, Topál L, Gazdag P, Szlovák J, Naveed M, Jost N, Nagy N, Varró A, Virág L, Koncz I. Cardiac electrophysiological effects of ibuprofen in dog and rabbit ventricular preparations: possible implication to enhanced proarrhythmic risk. Can J Physiol Pharmacol 2020; 99:102-109. [PMID: 32937079 DOI: 10.1139/cjpp-2020-0386] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Ibuprofen is a widely used nonsteroidal anti-inflammatory drug, which has recently been associated with increased cardiovascular risk, but its electrophysiological effects have not yet been properly studied in isolated cardiac preparations. We studied the effects of ibuprofen on action potential characteristics and several transmembrane ionic currents using the conventional microelectrode technique and the whole-cell configuration of the patch-clamp technique on cardiac preparations and enzymatically isolated ventricular myocytes. In dog (200 µM; n = 6) and rabbit (100 µM; n = 7) papillary muscles, ibuprofen moderately but significantly prolonged repolarization at 1 Hz stimulation frequency. In dog Purkinje fibers, repolarization was abbreviated and maximal rate of depolarization was depressed in a frequency-dependent manner. Levofloxacin (40 µM) alone did not alter repolarization, but augmented the ibuprofen-evoked repolarization lengthening in rabbit preparations (n = 7). In dog myocytes, ibuprofen (250 µM) did not significantly influence IK1, but decreased the amplitude of Ito and IKr potassium currents by 28.2% (60 mV) and 15.2% (20 mV), respectively. Ibuprofen also depressed INaL and ICa currents by 19.9% and 16.4%, respectively. We conclude that ibuprofen seems to be free from effects on action potential parameters at lower concentrations. However, at higher concentrations it may alter repolarization reserve, contributing to the observed proarrhythmic risk in patients.
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Affiliation(s)
- Bence Pászti
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - János Prorok
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary.,MTA-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary
| | - Tibor Magyar
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Tamás Árpádffy-Lovas
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Balázs Györe
- Department of Oral Surgery, Faculty of Dentistry, University of Szeged, Szeged, Hungary
| | - Leila Topál
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Péter Gazdag
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Jozefina Szlovák
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Muhammad Naveed
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Norbert Jost
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged, Hungary.,MTA-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary
| | - Norbert Nagy
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary.,MTA-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary
| | - András Varró
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged, Hungary.,MTA-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary
| | - László Virág
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged, Hungary.,MTA-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary
| | - István Koncz
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
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28
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Árpádffy-Lovas T, Husti Z, Baczkó I, Varró A, Virág L. Different effects of amiodarone and dofetilide on the dispersion of repolarization between well-coupled ventricular and Purkinje fibers 1. Can J Physiol Pharmacol 2020; 99:48-55. [PMID: 32692935 DOI: 10.1139/cjpp-2020-0234] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Increased transmural dispersion of repolarization is an established contributing factor to ventricular tachyarrhythmias. In this study, we evaluated the effect of chronic amiodarone treatment and acute administration of dofetilide in canine cardiac preparations containing electrotonically coupled Purkinje fibers (PFs) and ventricular muscle (VM) and compared the effects to those in uncoupled PF and VM preparations using the conventional microelectrode technique. Dispersion between PFs and VM was inferred from the difference in the respective action potential durations (APDs). In coupled preparations, amiodarone decreased the difference in APDs between PFs and VM, thus decreasing dispersion. In the same preparations, dofetilide increased the dispersion by causing a more pronounced prolongation in PFs. This prolongation was even more emphasized in uncoupled PF preparations, while the effect in VM was the same. In uncoupled preparations, amiodarone elicited no change on the difference in APDs. In conclusion, amiodarone decreased the dispersion between PFs and VM, while dofetilide increased it. The measured difference in APD between cardiac regions may be the affected by electrotonic coupling; thus, studying PFs and VM separately may lead to an over- or underestimation of dispersion.
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Affiliation(s)
- Tamás Árpádffy-Lovas
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Zoltán Husti
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - István Baczkó
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged, Hungary.,MTA-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary
| | - András Varró
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged, Hungary.,MTA-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary
| | - László Virág
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged, Hungary.,MTA-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary
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29
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Hornyik T, Castiglione A, Franke G, Perez-Feliz S, Major P, Hiripi L, Koren G, Bősze Z, Varró A, Zehender M, Brunner M, Bode C, Baczkó I, Odening KE. Transgenic LQT2, LQT5, and LQT2-5 rabbit models with decreased repolarisation reserve for prediction of drug-induced ventricular arrhythmias. Br J Pharmacol 2020; 177:3744-3759. [PMID: 32436214 PMCID: PMC7393202 DOI: 10.1111/bph.15098] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 04/09/2020] [Accepted: 04/23/2020] [Indexed: 12/21/2022] Open
Abstract
Background and Purpose Reliable prediction of pro‐arrhythmic side effects of novel drug candidates is still a major challenge. Although drug‐induced pro‐arrhythmia occurs primarily in patients with pre‐existing repolarisation disturbances, healthy animals are employed for pro‐arrhythmia testing. To improve current safety screening, transgenic long QT (LQTS) rabbit models with impaired repolarisation reserve were generated by overexpressing loss‐of‐function mutations of human HERG (HERG‐G628S, loss of IKr; LQT2), KCNE1 (KCNE1‐G52R, decreased IKs; LQT5), or both transgenes (LQT2‐5) in the heart. Experimental Approach Effects of K+ channel blockers on cardiac repolarisation and arrhythmia susceptibility were assessed in healthy wild‐type (WT) and LQTS rabbits using in vivo ECG and ex vivo monophasic action potential and ECG recordings in Langendorff‐perfused hearts. Key Results LQTS models reflect patients with clinically “silent” (LQT5) or “manifest” (LQT2 and LQT2‐5) impairment in cardiac repolarisation reserve: they were more sensitive in detecting IKr‐blocking (LQT5) or IK1/IKs‐blocking (LQT2 and LQT2‐5) properties of drugs compared to healthy WT animals. Impaired QT‐shortening capacity at fast heart rates was observed due to disturbed IKs function in LQT5 and LQT2‐5. Importantly, LQTS models exhibited higher incidence, longer duration, and more malignant types of ex vivo arrhythmias than WT. Conclusion and Implications LQTS models represent patients with reduced repolarisation reserve due to different pathomechanisms. As they demonstrate increased sensitivity to different specific ion channel blockers (IKr blockade in LQT5 and IK1 and IKs blockade in LQT2 and LQT2‐5), their combined use could provide more reliable and more thorough prediction of (multichannel‐based) pro‐arrhythmic potential of novel drug candidates.
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Affiliation(s)
- Tibor Hornyik
- Department of Cardiology and Angiology I, Heart Center University of Freiburg, Medical Faculty, Freiburg, Germany.,Institute of Experimental Cardiovascular Medicine, Heart Center University of Freiburg, Medical Faculty, Freiburg, Germany.,Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - Alessandro Castiglione
- Department of Cardiology and Angiology I, Heart Center University of Freiburg, Medical Faculty, Freiburg, Germany
| | - Gerlind Franke
- Department of Cardiology and Angiology I, Heart Center University of Freiburg, Medical Faculty, Freiburg, Germany
| | - Stefanie Perez-Feliz
- Department of Cardiology and Angiology I, Heart Center University of Freiburg, Medical Faculty, Freiburg, Germany.,Institute of Experimental Cardiovascular Medicine, Heart Center University of Freiburg, Medical Faculty, Freiburg, Germany
| | - Péter Major
- NARIC-Agricultural Biotechnology Institute, Animal Biotechnology Department, Gödöllő, Hungary
| | - László Hiripi
- NARIC-Agricultural Biotechnology Institute, Animal Biotechnology Department, Gödöllő, Hungary
| | - Gideon Koren
- Cardiovascular Research Center, Brown University, Providence, Rhode Island, USA
| | - Zsuzsanna Bősze
- NARIC-Agricultural Biotechnology Institute, Animal Biotechnology Department, Gödöllő, Hungary
| | - András Varró
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - Manfred Zehender
- Department of Cardiology and Angiology I, Heart Center University of Freiburg, Medical Faculty, Freiburg, Germany
| | - Michael Brunner
- Department of Cardiology and Angiology I, Heart Center University of Freiburg, Medical Faculty, Freiburg, Germany.,Department of Cardiology and Medical Intensive Care, St. Josefskrankenhaus, Freiburg, Germany
| | - Christoph Bode
- Department of Cardiology and Angiology I, Heart Center University of Freiburg, Medical Faculty, Freiburg, Germany
| | - István Baczkó
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - Katja E Odening
- Department of Cardiology and Angiology I, Heart Center University of Freiburg, Medical Faculty, Freiburg, Germany.,Institute of Experimental Cardiovascular Medicine, Heart Center University of Freiburg, Medical Faculty, Freiburg, Germany.,Translational Cardiology, Department of Cardiology, Inselspital, Bern University Hospital, and Institute of Physiology, University of Bern, Bern, Switzerland
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30
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Árpádffy-Lovas T, Baczkó I, Baláti B, Bitay M, Jost N, Lengyel C, Nagy N, Takács J, Varró A, Virág L. Electrical Restitution and Its Modifications by Antiarrhythmic Drugs in Undiseased Human Ventricular Muscle. Front Pharmacol 2020; 11:479. [PMID: 32425771 PMCID: PMC7203420 DOI: 10.3389/fphar.2020.00479] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 03/26/2020] [Indexed: 01/02/2023] Open
Abstract
Introduction Re-entry is a basic mechanism of ventricular fibrillation, which can be elicited by extrasystolic activity, but the timing of an extrasystole can be critical. The action potential duration (APD) of an extrasystole depends on the proximity of the preceding beat, and the relation between its timing and its APD is called electrical restitution. The aim of the present work was to study and compare the effect of several antiarrhythmic drugs on restitution in preparations from undiseased human ventricular muscle, and other mammalian species. Methods Action potentials were recorded in preparations obtained from rat, guinea pig, rabbit, and dog hearts; and from undiseased human donor hearts using the conventional microelectrode technique. Preparations were stimulated with different basic cycle lengths (BCLs) ranging from 300 to 5,000 ms. To study restitution, single test pulses were applied at every 20th beat while the preparation was driven at 1,000 ms BCL. Results Marked differences were found between the animal and human preparations regarding restitution and steady-state frequency dependent curves. In human ventricular muscle, restitution kinetics were slower in preparations with large phase 1 repolarization with shorter APDs at 1000 ms BCL compared to preparations with small phase 1. Preparations having APD longer than 300 ms at 1000 ms BCL had slower restitution kinetics than those having APD shorter than 250 ms. The selective IKr inhibitors E-4031 and sotalol increased overall APD and slowed the restitution kinetics, while IKs inhibition did not influence APD and electrical restitution. Mexiletine and nisoldipine shortened APD, but only mexiletine slowed restitution kinetics. Discussion Frequency dependent APD changes, including electrical restitution, were partly determined by the APD at the BCL. Small phase 1 associated with slower restitution suggests a role of Ito in restitution. APD prolonging drugs slowed restitution, while mexiletine, a known inhibitor of INa, shortened basic APD but also slowed restitution. These results indicate that although basic APD has an important role in restitution, other transmembrane currents, such as INa or Ito, can also affect restitution kinetics. This raises the possibility that ion channel modifier drugs slowing restitution kinetics may have antiarrhythmic properties by altering restitution.
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Affiliation(s)
- Tamás Árpádffy-Lovas
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged, Hungary
| | - István Baczkó
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged, Hungary
| | - Beáta Baláti
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Miklós Bitay
- Department of Cardiac Surgery, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Norbert Jost
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged, Hungary.,MTA-SZTE Research Group for Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary
| | - Csaba Lengyel
- First Department of Internal Medicine, University of Szeged, Szeged, Hungary
| | - Norbert Nagy
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary.,MTA-SZTE Research Group for Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary
| | - János Takács
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - András Varró
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged, Hungary.,MTA-SZTE Research Group for Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary
| | - László Virág
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged, Hungary
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31
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Kohajda Z, Loewe A, Tóth N, Varró A, Nagy N. The Cardiac Pacemaker Story-Fundamental Role of the Na +/Ca 2+ Exchanger in Spontaneous Automaticity. Front Pharmacol 2020; 11:516. [PMID: 32410993 PMCID: PMC7199655 DOI: 10.3389/fphar.2020.00516] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 04/01/2020] [Indexed: 01/01/2023] Open
Abstract
The electrophysiological mechanism of the sinus node automaticity was previously considered exclusively regulated by the so-called "funny current". However, parallel investigations increasingly emphasized the importance of the Ca2+-homeostasis and Na+/Ca2+ exchanger (NCX). Recently, increasing experimental evidence, as well as insight through mechanistic in silico modeling demonstrates the crucial role of the exchanger in sinus node pacemaking. NCX had a key role in the exciting story of discovery of sinus node pacemaking mechanisms, which recently settled with a consensus on the coupled-clock mechanism after decades of debate. This review focuses on the role of the Na+/Ca2+ exchanger from the early results and concepts to recent advances and attempts to give a balanced summary of the characteristics of the local, spontaneous, and rhythmic Ca2+ releases, the molecular control of the NCX and its role in the fight-or-flight response. Transgenic animal models and pharmacological manipulation of intracellular Ca2+ concentration and/or NCX demonstrate the pivotal function of the exchanger in sinus node automaticity. We also highlight where specific hypotheses regarding NCX function have been derived from computational modeling and require experimental validation. Nonselectivity of NCX inhibitors and the complex interplay of processes involved in Ca2+ handling render the design and interpretation of these experiments challenging.
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Affiliation(s)
- Zsófia Kohajda
- MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Axel Loewe
- Institute of Biomedical Engineering, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
| | - Noémi Tóth
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - András Varró
- MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Norbert Nagy
- MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
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32
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Orvos P, Kohajda Z, Szlovák J, Gazdag P, Árpádffy-Lovas T, Tóth D, Geramipour A, Tálosi L, Jost N, Varró A, Virág L. Evaluation of Possible Proarrhythmic Potency: Comparison of the Effect of Dofetilide, Cisapride, Sotalol, Terfenadine, and Verapamil on hERG and Native IKr Currents and on Cardiac Action Potential. Toxicol Sci 2020; 168:365-380. [PMID: 30561737 DOI: 10.1093/toxsci/kfy299] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The proarrhythmic potency of drugs is usually attributed to the IKr current block. During safety pharmacology testing analysis of IKr in cardiomyocytes was replaced by human ether-a-go-go-related gene (hERG) test using automated patch-clamp systems in stable transfected cell lines. Aim of this study was to compare the effect of proarrhythmic compounds on hERG and IKr currents and on cardiac action potential. The hERG current was measured by using both automated and manual patch-clamp methods on HEK293 cells. The native ion currents (IKr, INaL, ICaL) were recorded from rabbit ventricular myocytes by manual patch-clamp technique. Action potentials in rabbit ventricular muscle and undiseased human donor hearts were studied by conventional microelectrode technique. Dofetilide, cisapride, sotalol, terfenadine, and verapamil blocked hERG channels at 37°C with an IC50 of 7 nM, 18 nM, 343 μM, 165 nM, and 214 nM, respectively. Using manual patch-clamp, the IC50 values of sotalol and terfenadine were 78 µM and 31 nM, respectively. The IC50 values calculated from IKr measurements at 37°C were 13 nM, 26 nM, 52 μM, 54 nM, and 268 nM, respectively. Cisapride, dofetilide, and sotalol excessively lengthened, terfenadine, and verapamil did not influence the action potential duration. Terfenadine significantly inhibited INaL and moderately ICaL, verapamil blocked only ICaL. Automated hERG assays may over/underestimate proarrhythmic risk. Manual patch-clamp has substantially higher sensitivity to certain drugs. Action potential studies are also required to analyze complex multichannel effects. Therefore, manual patch-clamp and action potential experiments should be a part of preclinical safety tests.
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Affiliation(s)
- Péter Orvos
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine.,Department of Ophthalmology, University of Szeged, Szeged H-6720, Hungary
| | - Zsófia Kohajda
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine.,MTA-SZTE Research Group for Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged H-6720, Hungary
| | - Jozefina Szlovák
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine
| | - Péter Gazdag
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine
| | | | - Dániel Tóth
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine
| | - Amir Geramipour
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine
| | | | - Norbert Jost
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine.,MTA-SZTE Research Group for Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged H-6720, Hungary.,Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged H-6720, Hungary
| | - András Varró
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine.,MTA-SZTE Research Group for Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged H-6720, Hungary.,Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged H-6720, Hungary
| | - László Virág
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine.,MTA-SZTE Research Group for Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged H-6720, Hungary.,Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged H-6720, Hungary
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Kohajda Z, Tóth N, Szlovák J, Loewe A, Bitay G, Gazdag P, Prorok J, Jost N, Levijoki J, Pollesello P, Papp JG, Varró A, Nagy N. Novel Na +/Ca 2+ Exchanger Inhibitor ORM-10962 Supports Coupled Function of Funny-Current and Na +/Ca 2+ Exchanger in Pacemaking of Rabbit Sinus Node Tissue. Front Pharmacol 2020; 10:1632. [PMID: 32063850 PMCID: PMC7000430 DOI: 10.3389/fphar.2019.01632] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Accepted: 12/13/2019] [Indexed: 01/01/2023] Open
Abstract
Background and Purpose The exact mechanism of spontaneous pacemaking is not fully understood. Recent results suggest tight cooperation between intracellular Ca2+ handling and sarcolemmal ion channels. An important player of this crosstalk is the Na+/Ca2+ exchanger (NCX), however, direct pharmacological evidence was unavailable so far because of the lack of a selective inhibitor. We investigated the role of the NCX current in pacemaking and analyzed the functional consequences of the If-NCX coupling by applying the novel selective NCX inhibitor ORM-10962 on the sinus node (SAN). Experimental Approach Currents were measured by patch-clamp, Ca2+-transients were monitored by fluorescent optical method in rabbit SAN cells. Action potentials (AP) were recorded from rabbit SAN tissue preparations. Mechanistic computational data were obtained using the Yaniv et al. SAN model. Key Results ORM-10962 (ORM) marginally reduced the SAN pacemaking cycle length with a marked increase in the diastolic Ca2+ level as well as the transient amplitude. The bradycardic effect of NCX inhibition was augmented when the funny-current (If) was previously inhibited and vice versa, the effect of If was augmented when the Ca2+ handling was suppressed. Conclusion and Implications We confirmed the contribution of the NCX current to cardiac pacemaking using a novel NCX inhibitor. Our experimental and modeling data support a close cooperation between If and NCX providing an important functional consequence: these currents together establish a strong depolarization capacity providing important safety factor for stable pacemaking. Thus, after individual inhibition of If or NCX, excessive bradycardia or instability cannot be expected because each of these currents may compensate for the reduction of the other providing safe and rhythmic SAN pacemaking.
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Affiliation(s)
- Zsófia Kohajda
- MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Noémi Tóth
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Jozefina Szlovák
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Axel Loewe
- Institute of Biomedical Engineering, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
| | - Gergő Bitay
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Péter Gazdag
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - János Prorok
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Norbert Jost
- MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | | | | | - Julius Gy Papp
- MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - András Varró
- MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Norbert Nagy
- MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
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Nánási PP, Szabó Z, Kistamás K, Horváth B, Virág L, Jost N, Bányász T, Almássy J, Varró A. Implication of frequency-dependent protocols in antiarrhythmic and proarrhythmic drug testing. Prog Biophys Mol Biol 2019; 157:76-83. [PMID: 31726065 DOI: 10.1016/j.pbiomolbio.2019.11.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 10/30/2019] [Accepted: 11/01/2019] [Indexed: 01/20/2023]
Abstract
It has long been known that the electrophysiological effects of many cardioactive drugs strongly depend on the rate dependent frequency. This was recognized first for class I antiarrhythmic agents: their Vmax suppressive effect was attenuated at long cycle lengths. Later many Ca2+ channel blockers were also found to follow such kinetics. The explanation was provided by the modulated and the guarded receptor theories. Regarding the duration of cardiac action potentials (APD) an opposite frequency-dependence was observed, i.e. the drug-induced changes in APD were proportional with the cycle length of stimulation, therefore it was referred as "reverse rate-dependency". The beat-to-beat, or short term variability of APD (SV) has been recognized as an important proarrhythmic mechanism, its magnitude can be used as an arrhythmia predictor. SV is modulated by several cardioactive agents, however, these drugs modify also APD itself. In order to clear the drug-specific effects on SV from the concomitant unspecific APD-change related ones, the term of "relative variability" was introduced. Relative variability is increased by ion channel blockers that decrease the negative feedback control of APD (i.e. blockers of ICa, IKr and IKs) and also by elevation of cytosolic Ca2+. Cardiac arrhythmias are also often categorized according to the characteristic heart rate (tachy- and bradyarrhythmias). Tachycardia is proarrhythmic primarily due to the concomitant Ca2+ overload causing delayed afterdepolarizations. Early afterdepolarizations (EADs) are complications of the bradycardic heart. What is common in the reverse rate-dependent nature of drug action on APD, increased SV and EAD incidence associated with bradycardia.
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Affiliation(s)
- Péter P Nánási
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary; Department of Dental Physiology, Faculty of Dentistry, University of Debrecen, Debrecen, Hungary
| | - Zoltán Szabó
- Department of Emergency Medicine, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Kornél Kistamás
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Balázs Horváth
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - László Virág
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary; Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged, Hungary
| | - Norbert Jost
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary; Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged, Hungary; MTA-SZTE Research Group for Cardiovascular Pharmacology, Szeged, Hungary
| | - Tamás Bányász
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - János Almássy
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - András Varró
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary; Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged, Hungary; MTA-SZTE Research Group for Cardiovascular Pharmacology, Szeged, Hungary.
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Ferdinandy P, Baczkó I, Bencsik P, Giricz Z, Görbe A, Pacher P, Varga ZV, Varró A, Schulz R. Definition of hidden drug cardiotoxicity: paradigm change in cardiac safety testing and its clinical implications. Eur Heart J 2018; 40:1771-1777. [PMID: 29982507 PMCID: PMC6554653 DOI: 10.1093/eurheartj/ehy365] [Citation(s) in RCA: 78] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 03/12/2018] [Accepted: 06/11/2018] [Indexed: 12/18/2022] Open
Abstract
Unexpected cardiac adverse effects are the leading causes of discontinuation of clinical trials and withdrawal of drugs from the market. Since the original observations in the mid-90s, it has been well established that cardiovascular risk factors and comorbidities (such as ageing, hyperlipidaemia, and diabetes) and their medications (e.g. nitrate tolerance, adenosine triphosphate-dependent potassium inhibitor antidiabetic drugs, statins, etc.) may interfere with cardiac ischaemic tolerance and endogenous cardioprotective signalling pathways. Indeed drugs may exert unwanted effects on the diseased and treated heart that is hidden in the healthy myocardium. Hidden cardiotoxic effects may be due to (i) drug-induced enhancement of deleterious signalling due to ischaemia/reperfusion injury and/or the presence of risk factors and/or (ii) inhibition of cardioprotective survival signalling pathways, both of which may lead to ischaemia-related cell death and/or pro-arrhythmic effects. This led to a novel concept of ‘hidden cardiotoxicity’, defined as cardiotoxity of a drug that manifests only in the diseased heart with e.g. ischaemia/reperfusion injury and/or in the presence of its major comorbidities. Little is known on the mechanism of hidden cardiotoxocity, moreover, hidden cardiotoxicity cannot be revealed by the routinely used non-clinical cardiac safety testing methods on healthy animals or tissues. Therefore, here, we emphasize the need for development of novel cardiac safety testing platform involving combined experimental models of cardiac diseases (especially myocardial ischaemia/reperfusion and ischaemic conditioning) in the presence and absence of major cardiovascular comorbidities and/or cotreatments.
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Affiliation(s)
- Péter Ferdinandy
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, Nagyvárad tér 4, Budapest, Hungary
- Pharmahungary Group, Hajnoczy u. 6, Szeged, Hungary
| | - István Baczkó
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Dóm tér 12, Szeged, Hungary
| | | | - Zoltán Giricz
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, Nagyvárad tér 4, Budapest, Hungary
- Pharmahungary Group, Hajnoczy u. 6, Szeged, Hungary
| | - Anikó Görbe
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, Nagyvárad tér 4, Budapest, Hungary
- Pharmahungary Group, Hajnoczy u. 6, Szeged, Hungary
| | - Pál Pacher
- Laboratory of Cardiovascular Physiology and Tissue Injury, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Fishers Lane, Bethesda, MD, USA
| | - Zoltán V Varga
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, Nagyvárad tér 4, Budapest, Hungary
- Laboratory of Cardiovascular Physiology and Tissue Injury, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Fishers Lane, Bethesda, MD, USA
| | - András Varró
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Dóm tér 12, Szeged, Hungary
| | - Rainer Schulz
- Institute of Physiology, Justus-Liebig University of Giessen, Aulweg 129, Giessen, Germany
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36
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Britton OJ, Bueno-Orovio A, Virág L, Varró A, Rodriguez B. Corrigendum: The Electrogenic Na +/K + Pump Is a Key Determinant of Repolarization Abnormality Susceptibility in Human Ventricular Cardiomyocytes: A Population-Based Simulation Study. Front Physiol 2017; 8:954. [PMID: 29167647 PMCID: PMC5698266 DOI: 10.3389/fphys.2017.00954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Accepted: 11/08/2017] [Indexed: 11/13/2022] Open
Abstract
[This corrects the article on p. 278 in vol. 8, PMID: 28529489.].
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Affiliation(s)
- Oliver J. Britton
- Department of Computer Science, University of Oxford, Oxford, United Kingdom,*Correspondence: Oliver J. Britton
| | | | - László Virág
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - András Varró
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Blanca Rodriguez
- Department of Computer Science, University of Oxford, Oxford, United Kingdom
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Juhász V, Hornyik T, Benák A, Nagy N, Husti Z, Pap R, Sághy L, Virág L, Varró A, Baczkó I. Comparison of the effects of I K,ACh, I Kr, and I Na block in conscious dogs with atrial fibrillation and on action potentials in remodeled atrial trabeculae. Can J Physiol Pharmacol 2017; 96:18-25. [PMID: 28892643 DOI: 10.1139/cjpp-2017-0342] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia and a major cause of morbidity and mortality. Traditional antiarrhythmic agents used for restoration of sinus rhythm have limited efficacy in long-term AF and they may possess ventricular proarrhythmic adverse effects, especially in patients with structural heart disease. The acetylcholine receptor-activated potassium channel (IK,ACh) represents an atrial selective target for future AF management. We investigated the effects of the IK,ACh blocker tertiapin-Q (TQ), a derivative of the honeybee toxin tertiapin, on chronic atrial tachypacing-induced AF in conscious dogs, without the influence of anesthetics that modulate a number of cardiac ion channels. Action potentials (APs) were recorded from right atrial trabeculae isolated from dogs with AF. TQ significantly and dose-dependently reduced AF incidence and AF episode duration, prolonged atrial effective refractory period, and prolonged AP duration. The reference drugs propafenone and dofetilide, both used in the clinical management of AF, exerted similar effects against AF in vivo. Dofetilide prolonged atrial AP duration, whereas propafenone increased atrial conduction time. TQ and propafenone did not affect the QT interval, whereas dofetilide prolonged the QT interval. Our results show that inhibition of IK,ACh may represent a novel, atrial-specific target for the management of AF in chronic AF.
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Affiliation(s)
- Viktor Juhász
- a Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - Tibor Hornyik
- a Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - Attila Benák
- b 2nd Department of Internal Medicine and Cardiology Centre, University of Szeged, Szeged, Hungary
| | - Norbert Nagy
- c MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary
| | - Zoltán Husti
- a Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - Róbert Pap
- b 2nd Department of Internal Medicine and Cardiology Centre, University of Szeged, Szeged, Hungary
| | - László Sághy
- b 2nd Department of Internal Medicine and Cardiology Centre, University of Szeged, Szeged, Hungary
| | - László Virág
- a Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - András Varró
- a Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary.,c MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary
| | - István Baczkó
- a Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
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Papp R, Bett GCL, Lis A, Rasmusson RL, Baczkó I, Varró A, Salama G. Genomic upregulation of cardiac Cav1.2α and NCX1 by estrogen in women. Biol Sex Differ 2017; 8:26. [PMID: 28807015 PMCID: PMC5557418 DOI: 10.1186/s13293-017-0148-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Accepted: 08/04/2017] [Indexed: 01/08/2023] Open
Abstract
Background Women have a higher risk of lethal arrhythmias than men in long QT syndrome type 2 (LQTS2), but the mechanisms remain uncertain due to the limited availability of healthy control human tissue. We have previously reported that in female rabbits, estrogen increases arrhythmia risk in drug-induced LQTS2 by upregulating L-type Ca2+ (ICa,L) and sodium-calcium exchange (INCX) currents at the base of the epicardium by a genomic mechanism. This study investigates if the effects of estrogen on rabbit ICa,L and INCX apply to human hearts. Methods Postmortem human left ventricular tissue samples were probed with selective antibodies for regional heterogeneities of ion channel protein expression and compared to rabbit myocardium. Functionally, ICa,L and INCX were measured from female and male cardiomyocytes derived from human induced pluripotent stem cells (iPS-CMs) with the voltage-clamp technique from control and estrogen-treated iPS-CMs. Results In women (n = 12), Cav1.2α (primary subunit of the L-type calcium channel protein 1) and NCX1 (sodium-calcium exchange protein) levels were higher at the base than apex of the epicardium (40 ± 14 and 81 ± 30%, respectively, P < 0.05), but not in men (n = 6) or postmenopausal women (n = 6). Similarly, in cardiomyocytes derived from female human iPS-CMs, estrogen (1 nM, 1–2 days) increased ICa,L (31%, P < 0.05) and INCX (7.5-fold, − 90 mV, P < 0.01) and their mRNA levels (P < 0.05). Moreover, in male human iPS-CMs, estrogen failed to alter ICa,L and INCX. Conclusions The results show that estrogen upregulates cardiac ICa,L and INCX in women through genomic mechanisms that account for sex differences in Ca2+ handling and spatial heterogeneities of repolarization due to base-apex heterogeneities of Cav1.2α and NCX1. By analogy with rabbit studies, these effects account for human sex-difference in arrhythmia risk.
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Affiliation(s)
- Rita Papp
- Department of Bioengineering and the Department of Medicine, Heart and Vascular Institute, University of Pittsburgh, Pittsburgh, PA, 15261, USA.,Current Address: Ludwig Boltzmann Institute for Lung Vascular Research, Graz, Austria
| | - Glenna C L Bett
- Center for Cellular and Systems Electrophysiology, University at Buffalo, State University of New York, Buffalo, NY, 14214, USA.,Department of Physiology and Biophysics, University at Buffalo, State University of New York, Buffalo, NY, 14214, USA.,Obstetrics-Gynecology, University at Buffalo, State University of New York, Buffalo, NY, 14214, USA
| | - Agnieszka Lis
- Center for Cellular and Systems Electrophysiology, University at Buffalo, State University of New York, Buffalo, NY, 14214, USA.,Department of Physiology and Biophysics, University at Buffalo, State University of New York, Buffalo, NY, 14214, USA
| | - Randall L Rasmusson
- Center for Cellular and Systems Electrophysiology, University at Buffalo, State University of New York, Buffalo, NY, 14214, USA.,Department of Physiology and Biophysics, University at Buffalo, State University of New York, Buffalo, NY, 14214, USA
| | - István Baczkó
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - András Varró
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary.,MTA-SZTE Research Group for Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary
| | - Guy Salama
- Department of Bioengineering and the Department of Medicine, Heart and Vascular Institute, University of Pittsburgh, Pittsburgh, PA, 15261, USA. .,Department of Bioengineering and the Department of Medicine, Heart and Vascular Institute, University of Pittsburgh, 3550 Terrace Street, S628 Scaife Hall, Pittsburgh, PA, 15261, USA.
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Hategan L, Csányi B, Ördög B, Kákonyi K, Tringer A, Kiss O, Orosz A, Sághy L, Nagy I, Hegedűs Z, Rudas L, Széll M, Varró A, Forster T, Sepp R. A novel ‘splice site’ HCN4 Gene mutation, c.1737 + 1 G > T, causes familial bradycardia, reduced heart rate response, impaired chronotropic competence and increased short-term heart rate variability. Int J Cardiol 2017; 241:364-372. [DOI: 10.1016/j.ijcard.2017.04.058] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Revised: 03/22/2017] [Accepted: 04/19/2017] [Indexed: 11/26/2022]
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40
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Nánási PP, Magyar J, Varró A, Ördög B. Beat-to-beat variability of cardiac action potential duration: underlying mechanism and clinical implications. Can J Physiol Pharmacol 2017; 95:1230-1235. [PMID: 28746810 DOI: 10.1139/cjpp-2016-0597] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Beat-to-beat variability of cardiac action potential duration (short-term variability, SV) is a common feature of various cardiac preparations, including the human heart. Although it is believed to be one of the best arrhythmia predictors, the underlying mechanisms are not fully understood at present. The magnitude of SV is basically determined by the intensity of cell-to-cell coupling in multicellular preparations and by the duration of the action potential (APD). To compensate for the APD-dependent nature of SV, the concept of relative SV (RSV) has been introduced by normalizing the changes of SV to the concomitant changes in APD. RSV is reduced by ICa, IKr, and IKs while increased by INa, suggesting that ion currents involved in the negative feedback regulation of APD tend to keep RSV at a low level. RSV is also influenced by intracellular calcium concentration and tissue redox potential. The clinical implications of APD variability is discussed in detail.
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Affiliation(s)
- Péter P Nánási
- a Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary.,b Department of Dental Physiology and Pharmacology, Faculty of Dentistry, University of Debrecen, Debrecen, Hungary
| | - János Magyar
- a Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - András Varró
- c Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - Balázs Ördög
- c Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
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41
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Orosz A, Baczkó I, Nyiraty S, Körei AE, Putz Z, Takács R, Nemes A, Várkonyi TT, Balogh L, Ábrahám G, Kempler P, Papp JG, Varró A, Lengyel C. Increased Short-Term Beat-to-Beat QT Interval Variability in Patients with Impaired Glucose Tolerance. Front Endocrinol (Lausanne) 2017; 8:129. [PMID: 28659867 PMCID: PMC5468431 DOI: 10.3389/fendo.2017.00129] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2017] [Accepted: 05/29/2017] [Indexed: 01/02/2023] Open
Abstract
Prediabetic states and diabetes are important risk factors for cardiovascular morbidity and mortality. Determination of short-term QT interval variability (STVQT) is a non-invasive method for assessment of proarrhythmic risk. The aim of the study was to evaluate the STVQT in patients with impaired glucose tolerance (IGT). 18 IGT patients [age: 63 ± 11 years, body mass index (BMI): 31 ± 6 kg/m2, fasting glucose: 6.0 ± 0.4 mmol/l, 120 min postload glucose: 9.0 ± 1.0 mmol/l, hemoglobin A1c (HbA1c): 5.9 ± 0.4%; mean ± SD] and 18 healthy controls (age: 56 ± 9 years, BMI: 27 ± 5 kg/m2, fasting glucose: 5.2 ± 0.4 mmol/l, 120 min postload glucose: 5.5 ± 1.3 mmol/l, HbA1c: 5.4 ± 0.3%) were enrolled into the study. ECGs were recorded, processed, and analyzed off-line. The RR and QT intervals were expressed as the average of 30 consecutive beats, the temporal instability of beat-to-beat repolarization was characterized by calculating STVQT as follows: STVQT = Σ|QTn + 1 - QTn| (30x√2)-1. Autonomic function was assessed by means of standard cardiovascular reflex tests. There were no differences between IGT and control groups in QT (411 ± 43 vs 402 ± 39 ms) and QTc (431 ± 25 vs 424 ± 19 ms) intervals or QT dispersion (44 ± 13 vs 42 ± 17 ms). However, STVQT was significantly higher in IGT patients (5.0 ± 0.7 vs 3.7 ± 0.7, P < 0.0001). The elevated temporal STVQT in patients with IGT may be an early indicator of increased instability of cardiac repolarization during prediabetic conditions.
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Affiliation(s)
- Andrea Orosz
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - István Baczkó
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - Szabolcs Nyiraty
- First Department of Medicine, University of Szeged, Szeged, Hungary
| | - Anna E. Körei
- First Department of Medicine, Semmelweis University, Budapest, Hungary
| | - Zsuzsanna Putz
- First Department of Medicine, Semmelweis University, Budapest, Hungary
| | - Róbert Takács
- First Department of Medicine, University of Szeged, Szeged, Hungary
| | - Attila Nemes
- Second Department of Medicine and Cardiology Centre, University of Szeged, Szeged, Hungary
| | | | - László Balogh
- Juhász Gyula Faculty of Education, Institute of Physical Education and Sport Science, University of Szeged, Szeged, Hungary
| | - György Ábrahám
- First Department of Medicine, University of Szeged, Szeged, Hungary
| | - Péter Kempler
- First Department of Medicine, Semmelweis University, Budapest, Hungary
| | - Julius Gy. Papp
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
- MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary
| | - András Varró
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
- MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary
| | - Csaba Lengyel
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
- First Department of Medicine, University of Szeged, Szeged, Hungary
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Britton OJ, Bueno-Orovio A, Virág L, Varró A, Rodriguez B. The Electrogenic Na +/K + Pump Is a Key Determinant of Repolarization Abnormality Susceptibility in Human Ventricular Cardiomyocytes: A Population-Based Simulation Study. Front Physiol 2017; 8:278. [PMID: 28529489 PMCID: PMC5418229 DOI: 10.3389/fphys.2017.00278] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Accepted: 04/18/2017] [Indexed: 11/23/2022] Open
Abstract
Background: Cellular repolarization abnormalities occur unpredictably due to disease and drug effects, and can occur even in cardiomyocytes that exhibit normal action potentials (AP) under control conditions. Variability in ion channel densities may explain differences in this susceptibility to repolarization abnormalities. Here, we quantify the importance of key ionic mechanisms determining repolarization abnormalities following ionic block in human cardiomyocytes yielding normal APs under control conditions. Methods and Results: Sixty two AP recordings from non-diseased human heart preparations were used to construct a population of human ventricular models with normal APs and a wide range of ion channel densities. Multichannel ionic block was applied to investigate susceptibility to repolarization abnormalities. IKr block was necessary for the development of repolarization abnormalities. Models that developed repolarization abnormalities over the widest range of blocks possessed low Na+/K+ pump conductance below 50% of baseline, and ICaL conductance above 70% of baseline. Furthermore, INaK made the second largest contribution to repolarizing current in control simulations and the largest contribution under 75% IKr block. Reversing intracellular Na+ overload caused by reduced INaK was not sufficient to prevent abnormalities in models with low Na+/K+ pump conductance, while returning Na+/K+ pump conductance to normal substantially reduced abnormality occurrence, indicating INaK is an important repolarization current. Conclusions: INaK is an important determinant of repolarization abnormality susceptibility in human ventricular cardiomyocytes, through its contribution to repolarization current rather than homeostasis. While we found IKr block to be necessary for repolarization abnormalities to occur, INaK decrease, as in disease, may amplify the pro-arrhythmic risk of drug-induced IKr block in humans.
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Affiliation(s)
| | | | - László Virág
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of SzegedSzeged, Hungary
| | - András Varró
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of SzegedSzeged, Hungary
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43
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Gurabi Z, Patocskai B, Györe B, Virág L, Mátyus P, Papp JG, Varró A, Koncz I. Different electrophysiological effects of the levo- and dextro-rotatory isomers of mexiletine in isolated rabbit cardiac muscle. Can J Physiol Pharmacol 2017; 95:830-836. [PMID: 28226224 DOI: 10.1139/cjpp-2016-0599] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Racemic mexiletine is a widely used antiarrhythmic agent that blocks sodium channels. The effects of R-(-) and S-(+) mexiletine stereoisomers on maximum rate of depolarization ([Formula: see text]), conduction time, and repolarization have not yet been investigated in isolated cardiac preparations. We studied the effect of the R-(-) and S-(+) mexiletine on rabbit cardiac action potential parameters by using the conventional microelectrode technique. Both enantiomers at 20 μmol/L of therapeutically and experimentally relevant concentration, significantly depressed the [Formula: see text] at fast heart rates (BCLs 300-700 ms). R-(-) mexiletine has more potent inhibitory effect than S-(+) mexiletine. Both R-(-) and S-(+) mexiletine significantly inhibited the [Formula: see text] of early extrasystoles measured at 70 ms diastolic interval induced by S1-S2 stimuli. R-(-) mexiletine has more pronounced inhibitory effect than S-(+) mexiletine. Both R-(-) and S-(+) mexiletine increased significantly the ERP/APD90 ratio. The time constant (τ) of recovery of [Formula: see text] was found to be τ = 376.0 ± 77.8 ms for R-(-) mexiletine and τ = 227.1 ± 23.4 ms for S-(+) mexiletine, which indicates a slower offset kinetics for R-(-) mexiletine from sodium channels than that of the S-(+) enantiomer. These data suggest that R-(-) mexiletine might be a more potent antiarrhythmic agent than S-(+) mexiletine.
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Affiliation(s)
- Zsolt Gurabi
- a Department of Pharmacology & Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Bence Patocskai
- a Department of Pharmacology & Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary.,b First Department of Medicine, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany.,c DZHK (German Center for Cardiovascular Research), Partner Site Heidelberg-Mannheim, Germany
| | - Balázs Györe
- d Faculty of Dentistry, University of Szeged, Hungary
| | - László Virág
- a Department of Pharmacology & Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Péter Mátyus
- e Department of Organic Chemistry, Faculty of Pharmacology, Semmelweis University, Budapest, Hungary
| | - Julius Gy Papp
- a Department of Pharmacology & Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary.,f Hungarian Academy of Sciences - University of Szeged (MTA-SZTE) Research Group of Cardiovascular Pharmacology, Szeged, Hungary
| | - András Varró
- a Department of Pharmacology & Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary.,f Hungarian Academy of Sciences - University of Szeged (MTA-SZTE) Research Group of Cardiovascular Pharmacology, Szeged, Hungary
| | - István Koncz
- a Department of Pharmacology & Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
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Abu-Taha IH, Heijman J, Hippe HJ, Wolf NM, El-Armouche A, Nikolaev VO, Schäfer M, Würtz CM, Neef S, Voigt N, Baczkó I, Varró A, Müller M, Meder B, Katus HA, Spiger K, Vettel C, Lehmann LH, Backs J, Skolnik EY, Lutz S, Dobrev D, Wieland T. Nucleoside Diphosphate Kinase-C Suppresses cAMP Formation in Human Heart Failure. Circulation 2016; 135:881-897. [PMID: 27927712 DOI: 10.1161/circulationaha.116.022852] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Accepted: 11/23/2016] [Indexed: 01/29/2023]
Abstract
BACKGROUND Chronic heart failure (HF) is associated with altered signal transduction via β-adrenoceptors and G proteins and with reduced cAMP formation. Nucleoside diphosphate kinases (NDPKs) are enriched at the plasma membrane of patients with end-stage HF, but the functional consequences of this are largely unknown, particularly for NDPK-C. Here, we investigated the potential role of NDPK-C in cardiac cAMP formation and contractility. METHODS Real-time polymerase chain reaction, (far) Western blot, immunoprecipitation, and immunocytochemistry were used to study the expression, interaction with G proteins, and localization of NDPKs. cAMP levels were determined with immunoassays or fluorescent resonance energy transfer, and contractility was determined in cardiomyocytes (cell shortening) and in vivo (fractional shortening). RESULTS NDPK-C was essential for the formation of an NDPK-B/G protein complex. Protein and mRNA levels of NDPK-C were upregulated in end-stage human HF, in rats after long-term isoprenaline stimulation through osmotic minipumps, and after incubation of rat neonatal cardiomyocytes with isoprenaline. Isoprenaline also promoted translocation of NDPK-C to the plasma membrane. Overexpression of NDPK-C in cardiomyocytes increased cAMP levels and sensitized cardiomyocytes to isoprenaline-induced augmentation of contractility, whereas NDPK-C knockdown decreased cAMP levels. In vivo, depletion of NDPK-C in zebrafish embryos caused cardiac edema and ventricular dysfunction. NDPK-B knockout mice had unaltered NDPK-C expression but showed contractile dysfunction and exacerbated cardiac remodeling during long-term isoprenaline stimulation. In human end-stage HF, the complex formation between NDPK-C and Gαi2 was increased whereas the NDPK-C/Gαs interaction was decreased, producing a switch that may contribute to an NDPK-C-dependent cAMP reduction in HF. CONCLUSIONS Our findings identify NDPK-C as an essential requirement for both the interaction between NDPK isoforms and between NDPK isoforms and G proteins. NDPK-C is a novel critical regulator of β-adrenoceptor/cAMP signaling and cardiac contractility. By switching from Gαs to Gαi2 activation, NDPK-C may contribute to lower cAMP levels and the related contractile dysfunction in HF.
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Affiliation(s)
- Issam H Abu-Taha
- From Institute of Experimental and Clinical Pharmacology and Toxicology, Mannheim Medical Faculty (I.H.A.-T., N.M.W., K.S., C.V., S.L., T.W.), and Department of Internal Medicine III (H.-J.H., N.M.W., M.M., B.M., H.-A.K., L.H.L., J.B.), Heidelberg University, Heidelberg-Mannheim, Germany; Institute of Pharmacology, West German Heart and Vascular Center, University Duisburg-Essen, Essen, Germany (I.H.A.-T., J.H., M.S., N.V., D.D.); Institute of Pharmacology and Toxicology, University Medical Center Göttingen, Germany (A.E.-A., C.M.W., S.L.); Department of Pharmacology and Toxicology, Medical Faculty Carl Gustav Carus, Dresden University of Technology, Germany (A.E.-A.); Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Germany (V.O.N.); Department of Internal Medicine II, University of Regensburg, Germany (S.N.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B., A.V.); Division of Nephrology, New York University Langone Medical Center, New York (E.Y.S.); and DZHK (German Center for Cardiovascular Research), Partner Site HD/MA, Heidelberg-Mannheim, Germany (B.M., H.A.K., C.V., J.B., T.W.). The current affiliation for H.-J.H. is the Department of Cardiology and Angiology, University Hospital Schleswig-Holstein, Kiel, Germany
| | - Jordi Heijman
- From Institute of Experimental and Clinical Pharmacology and Toxicology, Mannheim Medical Faculty (I.H.A.-T., N.M.W., K.S., C.V., S.L., T.W.), and Department of Internal Medicine III (H.-J.H., N.M.W., M.M., B.M., H.-A.K., L.H.L., J.B.), Heidelberg University, Heidelberg-Mannheim, Germany; Institute of Pharmacology, West German Heart and Vascular Center, University Duisburg-Essen, Essen, Germany (I.H.A.-T., J.H., M.S., N.V., D.D.); Institute of Pharmacology and Toxicology, University Medical Center Göttingen, Germany (A.E.-A., C.M.W., S.L.); Department of Pharmacology and Toxicology, Medical Faculty Carl Gustav Carus, Dresden University of Technology, Germany (A.E.-A.); Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Germany (V.O.N.); Department of Internal Medicine II, University of Regensburg, Germany (S.N.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B., A.V.); Division of Nephrology, New York University Langone Medical Center, New York (E.Y.S.); and DZHK (German Center for Cardiovascular Research), Partner Site HD/MA, Heidelberg-Mannheim, Germany (B.M., H.A.K., C.V., J.B., T.W.). The current affiliation for H.-J.H. is the Department of Cardiology and Angiology, University Hospital Schleswig-Holstein, Kiel, Germany
| | - Hans-Jörg Hippe
- From Institute of Experimental and Clinical Pharmacology and Toxicology, Mannheim Medical Faculty (I.H.A.-T., N.M.W., K.S., C.V., S.L., T.W.), and Department of Internal Medicine III (H.-J.H., N.M.W., M.M., B.M., H.-A.K., L.H.L., J.B.), Heidelberg University, Heidelberg-Mannheim, Germany; Institute of Pharmacology, West German Heart and Vascular Center, University Duisburg-Essen, Essen, Germany (I.H.A.-T., J.H., M.S., N.V., D.D.); Institute of Pharmacology and Toxicology, University Medical Center Göttingen, Germany (A.E.-A., C.M.W., S.L.); Department of Pharmacology and Toxicology, Medical Faculty Carl Gustav Carus, Dresden University of Technology, Germany (A.E.-A.); Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Germany (V.O.N.); Department of Internal Medicine II, University of Regensburg, Germany (S.N.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B., A.V.); Division of Nephrology, New York University Langone Medical Center, New York (E.Y.S.); and DZHK (German Center for Cardiovascular Research), Partner Site HD/MA, Heidelberg-Mannheim, Germany (B.M., H.A.K., C.V., J.B., T.W.). The current affiliation for H.-J.H. is the Department of Cardiology and Angiology, University Hospital Schleswig-Holstein, Kiel, Germany
| | - Nadine M Wolf
- From Institute of Experimental and Clinical Pharmacology and Toxicology, Mannheim Medical Faculty (I.H.A.-T., N.M.W., K.S., C.V., S.L., T.W.), and Department of Internal Medicine III (H.-J.H., N.M.W., M.M., B.M., H.-A.K., L.H.L., J.B.), Heidelberg University, Heidelberg-Mannheim, Germany; Institute of Pharmacology, West German Heart and Vascular Center, University Duisburg-Essen, Essen, Germany (I.H.A.-T., J.H., M.S., N.V., D.D.); Institute of Pharmacology and Toxicology, University Medical Center Göttingen, Germany (A.E.-A., C.M.W., S.L.); Department of Pharmacology and Toxicology, Medical Faculty Carl Gustav Carus, Dresden University of Technology, Germany (A.E.-A.); Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Germany (V.O.N.); Department of Internal Medicine II, University of Regensburg, Germany (S.N.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B., A.V.); Division of Nephrology, New York University Langone Medical Center, New York (E.Y.S.); and DZHK (German Center for Cardiovascular Research), Partner Site HD/MA, Heidelberg-Mannheim, Germany (B.M., H.A.K., C.V., J.B., T.W.). The current affiliation for H.-J.H. is the Department of Cardiology and Angiology, University Hospital Schleswig-Holstein, Kiel, Germany
| | - Ali El-Armouche
- From Institute of Experimental and Clinical Pharmacology and Toxicology, Mannheim Medical Faculty (I.H.A.-T., N.M.W., K.S., C.V., S.L., T.W.), and Department of Internal Medicine III (H.-J.H., N.M.W., M.M., B.M., H.-A.K., L.H.L., J.B.), Heidelberg University, Heidelberg-Mannheim, Germany; Institute of Pharmacology, West German Heart and Vascular Center, University Duisburg-Essen, Essen, Germany (I.H.A.-T., J.H., M.S., N.V., D.D.); Institute of Pharmacology and Toxicology, University Medical Center Göttingen, Germany (A.E.-A., C.M.W., S.L.); Department of Pharmacology and Toxicology, Medical Faculty Carl Gustav Carus, Dresden University of Technology, Germany (A.E.-A.); Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Germany (V.O.N.); Department of Internal Medicine II, University of Regensburg, Germany (S.N.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B., A.V.); Division of Nephrology, New York University Langone Medical Center, New York (E.Y.S.); and DZHK (German Center for Cardiovascular Research), Partner Site HD/MA, Heidelberg-Mannheim, Germany (B.M., H.A.K., C.V., J.B., T.W.). The current affiliation for H.-J.H. is the Department of Cardiology and Angiology, University Hospital Schleswig-Holstein, Kiel, Germany
| | - Viacheslav O Nikolaev
- From Institute of Experimental and Clinical Pharmacology and Toxicology, Mannheim Medical Faculty (I.H.A.-T., N.M.W., K.S., C.V., S.L., T.W.), and Department of Internal Medicine III (H.-J.H., N.M.W., M.M., B.M., H.-A.K., L.H.L., J.B.), Heidelberg University, Heidelberg-Mannheim, Germany; Institute of Pharmacology, West German Heart and Vascular Center, University Duisburg-Essen, Essen, Germany (I.H.A.-T., J.H., M.S., N.V., D.D.); Institute of Pharmacology and Toxicology, University Medical Center Göttingen, Germany (A.E.-A., C.M.W., S.L.); Department of Pharmacology and Toxicology, Medical Faculty Carl Gustav Carus, Dresden University of Technology, Germany (A.E.-A.); Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Germany (V.O.N.); Department of Internal Medicine II, University of Regensburg, Germany (S.N.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B., A.V.); Division of Nephrology, New York University Langone Medical Center, New York (E.Y.S.); and DZHK (German Center for Cardiovascular Research), Partner Site HD/MA, Heidelberg-Mannheim, Germany (B.M., H.A.K., C.V., J.B., T.W.). The current affiliation for H.-J.H. is the Department of Cardiology and Angiology, University Hospital Schleswig-Holstein, Kiel, Germany
| | - Marina Schäfer
- From Institute of Experimental and Clinical Pharmacology and Toxicology, Mannheim Medical Faculty (I.H.A.-T., N.M.W., K.S., C.V., S.L., T.W.), and Department of Internal Medicine III (H.-J.H., N.M.W., M.M., B.M., H.-A.K., L.H.L., J.B.), Heidelberg University, Heidelberg-Mannheim, Germany; Institute of Pharmacology, West German Heart and Vascular Center, University Duisburg-Essen, Essen, Germany (I.H.A.-T., J.H., M.S., N.V., D.D.); Institute of Pharmacology and Toxicology, University Medical Center Göttingen, Germany (A.E.-A., C.M.W., S.L.); Department of Pharmacology and Toxicology, Medical Faculty Carl Gustav Carus, Dresden University of Technology, Germany (A.E.-A.); Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Germany (V.O.N.); Department of Internal Medicine II, University of Regensburg, Germany (S.N.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B., A.V.); Division of Nephrology, New York University Langone Medical Center, New York (E.Y.S.); and DZHK (German Center for Cardiovascular Research), Partner Site HD/MA, Heidelberg-Mannheim, Germany (B.M., H.A.K., C.V., J.B., T.W.). The current affiliation for H.-J.H. is the Department of Cardiology and Angiology, University Hospital Schleswig-Holstein, Kiel, Germany
| | - Christina M Würtz
- From Institute of Experimental and Clinical Pharmacology and Toxicology, Mannheim Medical Faculty (I.H.A.-T., N.M.W., K.S., C.V., S.L., T.W.), and Department of Internal Medicine III (H.-J.H., N.M.W., M.M., B.M., H.-A.K., L.H.L., J.B.), Heidelberg University, Heidelberg-Mannheim, Germany; Institute of Pharmacology, West German Heart and Vascular Center, University Duisburg-Essen, Essen, Germany (I.H.A.-T., J.H., M.S., N.V., D.D.); Institute of Pharmacology and Toxicology, University Medical Center Göttingen, Germany (A.E.-A., C.M.W., S.L.); Department of Pharmacology and Toxicology, Medical Faculty Carl Gustav Carus, Dresden University of Technology, Germany (A.E.-A.); Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Germany (V.O.N.); Department of Internal Medicine II, University of Regensburg, Germany (S.N.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B., A.V.); Division of Nephrology, New York University Langone Medical Center, New York (E.Y.S.); and DZHK (German Center for Cardiovascular Research), Partner Site HD/MA, Heidelberg-Mannheim, Germany (B.M., H.A.K., C.V., J.B., T.W.). The current affiliation for H.-J.H. is the Department of Cardiology and Angiology, University Hospital Schleswig-Holstein, Kiel, Germany
| | - Stefan Neef
- From Institute of Experimental and Clinical Pharmacology and Toxicology, Mannheim Medical Faculty (I.H.A.-T., N.M.W., K.S., C.V., S.L., T.W.), and Department of Internal Medicine III (H.-J.H., N.M.W., M.M., B.M., H.-A.K., L.H.L., J.B.), Heidelberg University, Heidelberg-Mannheim, Germany; Institute of Pharmacology, West German Heart and Vascular Center, University Duisburg-Essen, Essen, Germany (I.H.A.-T., J.H., M.S., N.V., D.D.); Institute of Pharmacology and Toxicology, University Medical Center Göttingen, Germany (A.E.-A., C.M.W., S.L.); Department of Pharmacology and Toxicology, Medical Faculty Carl Gustav Carus, Dresden University of Technology, Germany (A.E.-A.); Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Germany (V.O.N.); Department of Internal Medicine II, University of Regensburg, Germany (S.N.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B., A.V.); Division of Nephrology, New York University Langone Medical Center, New York (E.Y.S.); and DZHK (German Center for Cardiovascular Research), Partner Site HD/MA, Heidelberg-Mannheim, Germany (B.M., H.A.K., C.V., J.B., T.W.). The current affiliation for H.-J.H. is the Department of Cardiology and Angiology, University Hospital Schleswig-Holstein, Kiel, Germany
| | - Niels Voigt
- From Institute of Experimental and Clinical Pharmacology and Toxicology, Mannheim Medical Faculty (I.H.A.-T., N.M.W., K.S., C.V., S.L., T.W.), and Department of Internal Medicine III (H.-J.H., N.M.W., M.M., B.M., H.-A.K., L.H.L., J.B.), Heidelberg University, Heidelberg-Mannheim, Germany; Institute of Pharmacology, West German Heart and Vascular Center, University Duisburg-Essen, Essen, Germany (I.H.A.-T., J.H., M.S., N.V., D.D.); Institute of Pharmacology and Toxicology, University Medical Center Göttingen, Germany (A.E.-A., C.M.W., S.L.); Department of Pharmacology and Toxicology, Medical Faculty Carl Gustav Carus, Dresden University of Technology, Germany (A.E.-A.); Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Germany (V.O.N.); Department of Internal Medicine II, University of Regensburg, Germany (S.N.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B., A.V.); Division of Nephrology, New York University Langone Medical Center, New York (E.Y.S.); and DZHK (German Center for Cardiovascular Research), Partner Site HD/MA, Heidelberg-Mannheim, Germany (B.M., H.A.K., C.V., J.B., T.W.). The current affiliation for H.-J.H. is the Department of Cardiology and Angiology, University Hospital Schleswig-Holstein, Kiel, Germany
| | - István Baczkó
- From Institute of Experimental and Clinical Pharmacology and Toxicology, Mannheim Medical Faculty (I.H.A.-T., N.M.W., K.S., C.V., S.L., T.W.), and Department of Internal Medicine III (H.-J.H., N.M.W., M.M., B.M., H.-A.K., L.H.L., J.B.), Heidelberg University, Heidelberg-Mannheim, Germany; Institute of Pharmacology, West German Heart and Vascular Center, University Duisburg-Essen, Essen, Germany (I.H.A.-T., J.H., M.S., N.V., D.D.); Institute of Pharmacology and Toxicology, University Medical Center Göttingen, Germany (A.E.-A., C.M.W., S.L.); Department of Pharmacology and Toxicology, Medical Faculty Carl Gustav Carus, Dresden University of Technology, Germany (A.E.-A.); Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Germany (V.O.N.); Department of Internal Medicine II, University of Regensburg, Germany (S.N.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B., A.V.); Division of Nephrology, New York University Langone Medical Center, New York (E.Y.S.); and DZHK (German Center for Cardiovascular Research), Partner Site HD/MA, Heidelberg-Mannheim, Germany (B.M., H.A.K., C.V., J.B., T.W.). The current affiliation for H.-J.H. is the Department of Cardiology and Angiology, University Hospital Schleswig-Holstein, Kiel, Germany
| | - András Varró
- From Institute of Experimental and Clinical Pharmacology and Toxicology, Mannheim Medical Faculty (I.H.A.-T., N.M.W., K.S., C.V., S.L., T.W.), and Department of Internal Medicine III (H.-J.H., N.M.W., M.M., B.M., H.-A.K., L.H.L., J.B.), Heidelberg University, Heidelberg-Mannheim, Germany; Institute of Pharmacology, West German Heart and Vascular Center, University Duisburg-Essen, Essen, Germany (I.H.A.-T., J.H., M.S., N.V., D.D.); Institute of Pharmacology and Toxicology, University Medical Center Göttingen, Germany (A.E.-A., C.M.W., S.L.); Department of Pharmacology and Toxicology, Medical Faculty Carl Gustav Carus, Dresden University of Technology, Germany (A.E.-A.); Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Germany (V.O.N.); Department of Internal Medicine II, University of Regensburg, Germany (S.N.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B., A.V.); Division of Nephrology, New York University Langone Medical Center, New York (E.Y.S.); and DZHK (German Center for Cardiovascular Research), Partner Site HD/MA, Heidelberg-Mannheim, Germany (B.M., H.A.K., C.V., J.B., T.W.). The current affiliation for H.-J.H. is the Department of Cardiology and Angiology, University Hospital Schleswig-Holstein, Kiel, Germany
| | - Marion Müller
- From Institute of Experimental and Clinical Pharmacology and Toxicology, Mannheim Medical Faculty (I.H.A.-T., N.M.W., K.S., C.V., S.L., T.W.), and Department of Internal Medicine III (H.-J.H., N.M.W., M.M., B.M., H.-A.K., L.H.L., J.B.), Heidelberg University, Heidelberg-Mannheim, Germany; Institute of Pharmacology, West German Heart and Vascular Center, University Duisburg-Essen, Essen, Germany (I.H.A.-T., J.H., M.S., N.V., D.D.); Institute of Pharmacology and Toxicology, University Medical Center Göttingen, Germany (A.E.-A., C.M.W., S.L.); Department of Pharmacology and Toxicology, Medical Faculty Carl Gustav Carus, Dresden University of Technology, Germany (A.E.-A.); Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Germany (V.O.N.); Department of Internal Medicine II, University of Regensburg, Germany (S.N.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B., A.V.); Division of Nephrology, New York University Langone Medical Center, New York (E.Y.S.); and DZHK (German Center for Cardiovascular Research), Partner Site HD/MA, Heidelberg-Mannheim, Germany (B.M., H.A.K., C.V., J.B., T.W.). The current affiliation for H.-J.H. is the Department of Cardiology and Angiology, University Hospital Schleswig-Holstein, Kiel, Germany
| | - Benjamin Meder
- From Institute of Experimental and Clinical Pharmacology and Toxicology, Mannheim Medical Faculty (I.H.A.-T., N.M.W., K.S., C.V., S.L., T.W.), and Department of Internal Medicine III (H.-J.H., N.M.W., M.M., B.M., H.-A.K., L.H.L., J.B.), Heidelberg University, Heidelberg-Mannheim, Germany; Institute of Pharmacology, West German Heart and Vascular Center, University Duisburg-Essen, Essen, Germany (I.H.A.-T., J.H., M.S., N.V., D.D.); Institute of Pharmacology and Toxicology, University Medical Center Göttingen, Germany (A.E.-A., C.M.W., S.L.); Department of Pharmacology and Toxicology, Medical Faculty Carl Gustav Carus, Dresden University of Technology, Germany (A.E.-A.); Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Germany (V.O.N.); Department of Internal Medicine II, University of Regensburg, Germany (S.N.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B., A.V.); Division of Nephrology, New York University Langone Medical Center, New York (E.Y.S.); and DZHK (German Center for Cardiovascular Research), Partner Site HD/MA, Heidelberg-Mannheim, Germany (B.M., H.A.K., C.V., J.B., T.W.). The current affiliation for H.-J.H. is the Department of Cardiology and Angiology, University Hospital Schleswig-Holstein, Kiel, Germany
| | - Hugo A Katus
- From Institute of Experimental and Clinical Pharmacology and Toxicology, Mannheim Medical Faculty (I.H.A.-T., N.M.W., K.S., C.V., S.L., T.W.), and Department of Internal Medicine III (H.-J.H., N.M.W., M.M., B.M., H.-A.K., L.H.L., J.B.), Heidelberg University, Heidelberg-Mannheim, Germany; Institute of Pharmacology, West German Heart and Vascular Center, University Duisburg-Essen, Essen, Germany (I.H.A.-T., J.H., M.S., N.V., D.D.); Institute of Pharmacology and Toxicology, University Medical Center Göttingen, Germany (A.E.-A., C.M.W., S.L.); Department of Pharmacology and Toxicology, Medical Faculty Carl Gustav Carus, Dresden University of Technology, Germany (A.E.-A.); Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Germany (V.O.N.); Department of Internal Medicine II, University of Regensburg, Germany (S.N.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B., A.V.); Division of Nephrology, New York University Langone Medical Center, New York (E.Y.S.); and DZHK (German Center for Cardiovascular Research), Partner Site HD/MA, Heidelberg-Mannheim, Germany (B.M., H.A.K., C.V., J.B., T.W.). The current affiliation for H.-J.H. is the Department of Cardiology and Angiology, University Hospital Schleswig-Holstein, Kiel, Germany
| | - Katharina Spiger
- From Institute of Experimental and Clinical Pharmacology and Toxicology, Mannheim Medical Faculty (I.H.A.-T., N.M.W., K.S., C.V., S.L., T.W.), and Department of Internal Medicine III (H.-J.H., N.M.W., M.M., B.M., H.-A.K., L.H.L., J.B.), Heidelberg University, Heidelberg-Mannheim, Germany; Institute of Pharmacology, West German Heart and Vascular Center, University Duisburg-Essen, Essen, Germany (I.H.A.-T., J.H., M.S., N.V., D.D.); Institute of Pharmacology and Toxicology, University Medical Center Göttingen, Germany (A.E.-A., C.M.W., S.L.); Department of Pharmacology and Toxicology, Medical Faculty Carl Gustav Carus, Dresden University of Technology, Germany (A.E.-A.); Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Germany (V.O.N.); Department of Internal Medicine II, University of Regensburg, Germany (S.N.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B., A.V.); Division of Nephrology, New York University Langone Medical Center, New York (E.Y.S.); and DZHK (German Center for Cardiovascular Research), Partner Site HD/MA, Heidelberg-Mannheim, Germany (B.M., H.A.K., C.V., J.B., T.W.). The current affiliation for H.-J.H. is the Department of Cardiology and Angiology, University Hospital Schleswig-Holstein, Kiel, Germany
| | - Christiane Vettel
- From Institute of Experimental and Clinical Pharmacology and Toxicology, Mannheim Medical Faculty (I.H.A.-T., N.M.W., K.S., C.V., S.L., T.W.), and Department of Internal Medicine III (H.-J.H., N.M.W., M.M., B.M., H.-A.K., L.H.L., J.B.), Heidelberg University, Heidelberg-Mannheim, Germany; Institute of Pharmacology, West German Heart and Vascular Center, University Duisburg-Essen, Essen, Germany (I.H.A.-T., J.H., M.S., N.V., D.D.); Institute of Pharmacology and Toxicology, University Medical Center Göttingen, Germany (A.E.-A., C.M.W., S.L.); Department of Pharmacology and Toxicology, Medical Faculty Carl Gustav Carus, Dresden University of Technology, Germany (A.E.-A.); Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Germany (V.O.N.); Department of Internal Medicine II, University of Regensburg, Germany (S.N.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B., A.V.); Division of Nephrology, New York University Langone Medical Center, New York (E.Y.S.); and DZHK (German Center for Cardiovascular Research), Partner Site HD/MA, Heidelberg-Mannheim, Germany (B.M., H.A.K., C.V., J.B., T.W.). The current affiliation for H.-J.H. is the Department of Cardiology and Angiology, University Hospital Schleswig-Holstein, Kiel, Germany
| | - Lorenz H Lehmann
- From Institute of Experimental and Clinical Pharmacology and Toxicology, Mannheim Medical Faculty (I.H.A.-T., N.M.W., K.S., C.V., S.L., T.W.), and Department of Internal Medicine III (H.-J.H., N.M.W., M.M., B.M., H.-A.K., L.H.L., J.B.), Heidelberg University, Heidelberg-Mannheim, Germany; Institute of Pharmacology, West German Heart and Vascular Center, University Duisburg-Essen, Essen, Germany (I.H.A.-T., J.H., M.S., N.V., D.D.); Institute of Pharmacology and Toxicology, University Medical Center Göttingen, Germany (A.E.-A., C.M.W., S.L.); Department of Pharmacology and Toxicology, Medical Faculty Carl Gustav Carus, Dresden University of Technology, Germany (A.E.-A.); Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Germany (V.O.N.); Department of Internal Medicine II, University of Regensburg, Germany (S.N.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B., A.V.); Division of Nephrology, New York University Langone Medical Center, New York (E.Y.S.); and DZHK (German Center for Cardiovascular Research), Partner Site HD/MA, Heidelberg-Mannheim, Germany (B.M., H.A.K., C.V., J.B., T.W.). The current affiliation for H.-J.H. is the Department of Cardiology and Angiology, University Hospital Schleswig-Holstein, Kiel, Germany
| | - Johannes Backs
- From Institute of Experimental and Clinical Pharmacology and Toxicology, Mannheim Medical Faculty (I.H.A.-T., N.M.W., K.S., C.V., S.L., T.W.), and Department of Internal Medicine III (H.-J.H., N.M.W., M.M., B.M., H.-A.K., L.H.L., J.B.), Heidelberg University, Heidelberg-Mannheim, Germany; Institute of Pharmacology, West German Heart and Vascular Center, University Duisburg-Essen, Essen, Germany (I.H.A.-T., J.H., M.S., N.V., D.D.); Institute of Pharmacology and Toxicology, University Medical Center Göttingen, Germany (A.E.-A., C.M.W., S.L.); Department of Pharmacology and Toxicology, Medical Faculty Carl Gustav Carus, Dresden University of Technology, Germany (A.E.-A.); Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Germany (V.O.N.); Department of Internal Medicine II, University of Regensburg, Germany (S.N.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B., A.V.); Division of Nephrology, New York University Langone Medical Center, New York (E.Y.S.); and DZHK (German Center for Cardiovascular Research), Partner Site HD/MA, Heidelberg-Mannheim, Germany (B.M., H.A.K., C.V., J.B., T.W.). The current affiliation for H.-J.H. is the Department of Cardiology and Angiology, University Hospital Schleswig-Holstein, Kiel, Germany
| | - Edward Y Skolnik
- From Institute of Experimental and Clinical Pharmacology and Toxicology, Mannheim Medical Faculty (I.H.A.-T., N.M.W., K.S., C.V., S.L., T.W.), and Department of Internal Medicine III (H.-J.H., N.M.W., M.M., B.M., H.-A.K., L.H.L., J.B.), Heidelberg University, Heidelberg-Mannheim, Germany; Institute of Pharmacology, West German Heart and Vascular Center, University Duisburg-Essen, Essen, Germany (I.H.A.-T., J.H., M.S., N.V., D.D.); Institute of Pharmacology and Toxicology, University Medical Center Göttingen, Germany (A.E.-A., C.M.W., S.L.); Department of Pharmacology and Toxicology, Medical Faculty Carl Gustav Carus, Dresden University of Technology, Germany (A.E.-A.); Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Germany (V.O.N.); Department of Internal Medicine II, University of Regensburg, Germany (S.N.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B., A.V.); Division of Nephrology, New York University Langone Medical Center, New York (E.Y.S.); and DZHK (German Center for Cardiovascular Research), Partner Site HD/MA, Heidelberg-Mannheim, Germany (B.M., H.A.K., C.V., J.B., T.W.). The current affiliation for H.-J.H. is the Department of Cardiology and Angiology, University Hospital Schleswig-Holstein, Kiel, Germany
| | - Susanne Lutz
- From Institute of Experimental and Clinical Pharmacology and Toxicology, Mannheim Medical Faculty (I.H.A.-T., N.M.W., K.S., C.V., S.L., T.W.), and Department of Internal Medicine III (H.-J.H., N.M.W., M.M., B.M., H.-A.K., L.H.L., J.B.), Heidelberg University, Heidelberg-Mannheim, Germany; Institute of Pharmacology, West German Heart and Vascular Center, University Duisburg-Essen, Essen, Germany (I.H.A.-T., J.H., M.S., N.V., D.D.); Institute of Pharmacology and Toxicology, University Medical Center Göttingen, Germany (A.E.-A., C.M.W., S.L.); Department of Pharmacology and Toxicology, Medical Faculty Carl Gustav Carus, Dresden University of Technology, Germany (A.E.-A.); Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Germany (V.O.N.); Department of Internal Medicine II, University of Regensburg, Germany (S.N.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B., A.V.); Division of Nephrology, New York University Langone Medical Center, New York (E.Y.S.); and DZHK (German Center for Cardiovascular Research), Partner Site HD/MA, Heidelberg-Mannheim, Germany (B.M., H.A.K., C.V., J.B., T.W.). The current affiliation for H.-J.H. is the Department of Cardiology and Angiology, University Hospital Schleswig-Holstein, Kiel, Germany
| | - Dobromir Dobrev
- From Institute of Experimental and Clinical Pharmacology and Toxicology, Mannheim Medical Faculty (I.H.A.-T., N.M.W., K.S., C.V., S.L., T.W.), and Department of Internal Medicine III (H.-J.H., N.M.W., M.M., B.M., H.-A.K., L.H.L., J.B.), Heidelberg University, Heidelberg-Mannheim, Germany; Institute of Pharmacology, West German Heart and Vascular Center, University Duisburg-Essen, Essen, Germany (I.H.A.-T., J.H., M.S., N.V., D.D.); Institute of Pharmacology and Toxicology, University Medical Center Göttingen, Germany (A.E.-A., C.M.W., S.L.); Department of Pharmacology and Toxicology, Medical Faculty Carl Gustav Carus, Dresden University of Technology, Germany (A.E.-A.); Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Germany (V.O.N.); Department of Internal Medicine II, University of Regensburg, Germany (S.N.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B., A.V.); Division of Nephrology, New York University Langone Medical Center, New York (E.Y.S.); and DZHK (German Center for Cardiovascular Research), Partner Site HD/MA, Heidelberg-Mannheim, Germany (B.M., H.A.K., C.V., J.B., T.W.). The current affiliation for H.-J.H. is the Department of Cardiology and Angiology, University Hospital Schleswig-Holstein, Kiel, Germany.
| | - Thomas Wieland
- From Institute of Experimental and Clinical Pharmacology and Toxicology, Mannheim Medical Faculty (I.H.A.-T., N.M.W., K.S., C.V., S.L., T.W.), and Department of Internal Medicine III (H.-J.H., N.M.W., M.M., B.M., H.-A.K., L.H.L., J.B.), Heidelberg University, Heidelberg-Mannheim, Germany; Institute of Pharmacology, West German Heart and Vascular Center, University Duisburg-Essen, Essen, Germany (I.H.A.-T., J.H., M.S., N.V., D.D.); Institute of Pharmacology and Toxicology, University Medical Center Göttingen, Germany (A.E.-A., C.M.W., S.L.); Department of Pharmacology and Toxicology, Medical Faculty Carl Gustav Carus, Dresden University of Technology, Germany (A.E.-A.); Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Germany (V.O.N.); Department of Internal Medicine II, University of Regensburg, Germany (S.N.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B., A.V.); Division of Nephrology, New York University Langone Medical Center, New York (E.Y.S.); and DZHK (German Center for Cardiovascular Research), Partner Site HD/MA, Heidelberg-Mannheim, Germany (B.M., H.A.K., C.V., J.B., T.W.). The current affiliation for H.-J.H. is the Department of Cardiology and Angiology, University Hospital Schleswig-Holstein, Kiel, Germany.
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Kohajda Z, Farkas-Morvay N, Jost N, Nagy N, Geramipour A, Horváth A, Varga RS, Hornyik T, Corici C, Acsai K, Horváth B, Prorok J, Ördög B, Déri S, Tóth D, Levijoki J, Pollesello P, Koskelainen T, Otsomaa L, Tóth A, Baczkó I, Leprán I, Nánási PP, Papp JG, Varró A, Virág L. The Effect of a Novel Highly Selective Inhibitor of the Sodium/Calcium Exchanger (NCX) on Cardiac Arrhythmias in In Vitro and In Vivo Experiments. PLoS One 2016; 11:e0166041. [PMID: 27832106 PMCID: PMC5104402 DOI: 10.1371/journal.pone.0166041] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Accepted: 10/21/2016] [Indexed: 11/18/2022] Open
Abstract
Background In this study the effects of a new, highly selective sodium-calcium exchanger (NCX) inhibitor, ORM-10962 were investigated on cardiac NCX current, Ca2+ transients, cell shortening and in experimental arrhythmias. The level of selectivity of the novel inhibitor on several major transmembrane ion currents (L-type Ca2+ current, major repolarizing K+ currents, late Na+ current, Na+/K+ pump current) was also determined. Methods Ion currents in single dog ventricular cells (cardiac myocytes; CM), and action potentials in dog cardiac multicellular preparations were recorded utilizing the whole-cell patch clamp and standard microelectrode techniques, respectively. Ca2+ transients and cell shortening were measured in fluorescent dye loaded isolated dog myocytes. Antiarrhythmic effects of ORM-10962 were studied in anesthetized ouabain (10 μg/kg/min i.v.) pretreated guinea pigs and in ischemia-reperfusion models (I/R) of anesthetized coronary artery occluded rats and Langendorff perfused guinea pigs hearts. Results ORM-10962 significantly reduced the inward/outward NCX currents with estimated EC50 values of 55/67 nM, respectively. The compound, even at a high concentration of 1 μM, did not modify significantly the magnitude of ICaL in CMs, neither had any apparent influence on the inward rectifier, transient outward, the rapid and slow components of the delayed rectifier potassium currents, the late and peak sodium and Na+/K+ pump currents. NCX inhibition exerted moderate positive inotropic effect under normal condition, negative inotropy when reverse, and further positive inotropic effect when forward mode was facilitated. In dog Purkinje fibres 1 μM ORM-10962 decreased the amplitude of digoxin induced delayed afterdepolarizations (DADs). Pre-treatment with 0.3 mg/kg ORM-10962 (i.v.) 10 min before starting ouabain infusion significantly delayed the development and recurrence of ventricular extrasystoles (by about 50%) or ventricular tachycardia (by about 30%) in anesthetized guinea pigs. On the contrary, ORM-10962 pre-treatment had no apparent influence on the time of onset or the severity of I/R induced arrhythmias in anesthetized rats and in Langendorff perfused guinea-pig hearts. Conclusions The present study provides strong evidence for a high efficacy and selectivity of the NCX-inhibitory effect of ORM-10962. Selective NCX inhibition can exert positive as well as negative inotropic effect depending on the actual operation mode of NCX. Selective NCX blockade may contribute to the prevention of DAD based arrhythmogenesis, in vivo, however, its effect on I/R induced arrhythmias is still uncertain.
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Affiliation(s)
- Zsófia Kohajda
- MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary
| | - Nikolett Farkas-Morvay
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Norbert Jost
- MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary
- Department of Pathophysiology, "Victor Babes" University of Medicine and Pharmacy, Timisoara, Romania
| | - Norbert Nagy
- MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary
| | - Amir Geramipour
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - András Horváth
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
- MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary
| | - Richárd S. Varga
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Tibor Hornyik
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Claudia Corici
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Károly Acsai
- MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary
| | - Balázs Horváth
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - János Prorok
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Balázs Ördög
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Szilvia Déri
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Dániel Tóth
- MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary
| | | | | | | | | | - András Tóth
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
- MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary
| | - István Baczkó
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
- Department of Pathophysiology, "Victor Babes" University of Medicine and Pharmacy, Timisoara, Romania
| | - István Leprán
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Péter P. Nánási
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
- Department of Dental Physiology and Pharmacology, Faculty of Dentistry, University of Debrecen, Debrecen, Hungary
| | - Julius Gy Papp
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
- MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary
| | - András Varró
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
- MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary
| | - László Virág
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
- MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary
- * E-mail:
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Geramipour A, Kohajda Z, Corici C, Prorok J, Szakonyi Z, Oravecz K, Márton Z, Nagy N, Tóth A, Acsai K, Virág L, Varró A, Jost N. The investigation of the cellular electrophysiological and antiarrhythmic effects of a novel selective sodium-calcium exchanger inhibitor, GYKB-6635, in canine and guinea-pig hearts. Can J Physiol Pharmacol 2016; 94:1090-1101. [PMID: 27508313 DOI: 10.1139/cjpp-2015-0566] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
The sodium-calcium exchanger (NCX) is considered as the major transmembrane transport mechanism that controls Ca2+ homeostasis. Its contribution to the cardiac repolarization has not yet been directly studied due to lack of specific inhibitors, so that an urgent need for more selective compounds. In this study, the electrophysiological effects of GYKB-6635, a novel NCX inhibitor, on the NCX, L-type calcium, and main repolarizing potassium currents as well as action potential (AP) parameters were investigated. Ion currents and AP recordings were investigated by applying the whole-cell patch clamp and standard microelectrode techniques in canine heart at 37 °C. Effects of GYKB-6635 were studied in ouabain-induced arrhythmias in isolated guinea-pig hearts. At a concentration of 1 μmol/L, GYKB significantly reduced both the inward and outward NCX currents (57% and 58%, respectively). Even at a high concentration (10 μmol/L), GYKB-6635 did not change the ICaL, the maximum rate of depolarization (dV/dtmax), the main repolarizing K+ currents, and the main AP parameters. GYKB-6635 pre-treatment significantly delayed the time to the development of ventricular fibrillation (by about 18%). It is concluded that GYKB-6635 is a potent and highly selective inhibitor of the cardiac NCX and, in addition, it is suggested to also contribute to the prevention of DAD-based arrhythmias.
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Affiliation(s)
- Amir Geramipour
- a Department of Pharmacology & Pharmacotherapy, Faculty of Medicine, University of Szeged, H-6720 Szeged, Hungary
| | - Zsófia Kohajda
- b MTA-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary
| | - Claudia Corici
- a Department of Pharmacology & Pharmacotherapy, Faculty of Medicine, University of Szeged, H-6720 Szeged, Hungary
| | - János Prorok
- a Department of Pharmacology & Pharmacotherapy, Faculty of Medicine, University of Szeged, H-6720 Szeged, Hungary
| | - Zsolt Szakonyi
- c Institute of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Szeged, H-6720 Szeged, Hungary
| | - Kinga Oravecz
- a Department of Pharmacology & Pharmacotherapy, Faculty of Medicine, University of Szeged, H-6720 Szeged, Hungary
| | - Zoltán Márton
- a Department of Pharmacology & Pharmacotherapy, Faculty of Medicine, University of Szeged, H-6720 Szeged, Hungary
| | - Norbert Nagy
- b MTA-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary
| | - András Tóth
- a Department of Pharmacology & Pharmacotherapy, Faculty of Medicine, University of Szeged, H-6720 Szeged, Hungary.,b MTA-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary
| | - Károly Acsai
- b MTA-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary
| | - László Virág
- a Department of Pharmacology & Pharmacotherapy, Faculty of Medicine, University of Szeged, H-6720 Szeged, Hungary.,b MTA-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary
| | - András Varró
- a Department of Pharmacology & Pharmacotherapy, Faculty of Medicine, University of Szeged, H-6720 Szeged, Hungary.,b MTA-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary
| | - Norbert Jost
- b MTA-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary.,d "Victor Babes" University of Medicine and Pharmacy, Timisoara, Romania
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Kui P, Orosz S, Takács H, Sarusi A, Csík N, Rárosi F, Csekő C, Varró A, Papp JG, Forster T, Farkas AS, Farkas A. New in vitro model for proarrhythmia safety screening: IKs inhibition potentiates the QTc prolonging effect of IKr inhibitors in isolated guinea pig hearts. J Pharmacol Toxicol Methods 2016; 80:26-34. [DOI: 10.1016/j.vascn.2016.04.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Revised: 04/01/2016] [Accepted: 04/04/2016] [Indexed: 01/25/2023]
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Christ T, Kovács PP, Acsai K, Knaut M, Eschenhagen T, Jost N, Varró A, Wettwer E, Ravens U. Block of Na(+)/Ca(2+) exchanger by SEA0400 in human right atrial preparations from patients in sinus rhythm and in atrial fibrillation. Eur J Pharmacol 2016; 788:286-293. [PMID: 27373849 DOI: 10.1016/j.ejphar.2016.06.050] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 06/17/2016] [Accepted: 06/28/2016] [Indexed: 01/10/2023]
Abstract
The Na(+)/Ca(2+) exchanger (NCX) plays a major role in myocardial Ca(2+) homoeostasis, but is also considered to contribute to the electrical instability and contractile dysfunction in chronic atrial fibrillation (AF). Here we have investigated the effects of the selective NCX blocker SEA0400 in human right atrial cardiomyocytes from patients in sinus rhythm (SR) and AF in order to obtain electrophysiological evidence for putative antiarrhythmic activity of this new class of drugs. Action potentials were measured in right atrial trabeculae using conventional microelectrodes. Human myocytes were enzymatically isolated. Rat atrial and ventricular cardiomyocytes were used for comparison. Using perforated-patch, NCX was measured as Ni(2+)-sensitive current during ramp pulses. In ruptured-patch experiments, NCX current was activated by changing the extracellular Ca(2+) concentration from 0 to 1mM in Na(+)-free bath solution (100mM Na(+) intracellular, "Hilgemann protocol"). Although SEA0400 was effective in rat cardiomyocytes, 10µM did not influence action potentials and contractility, neither in SR nor AF. SEA0400 (10μM) also failed to affect human atrial NCX current measured with perforated patch. With the "Hilgemann protocol" SEA0400 concentration-dependently suppressed human atrial NCX current, and its amplitude was larger in AF than in SR cardiomyocytes. Our results confirm higher NCX activity in AF than SR. SEA0400 fails to block Ni(2+)-sensitive current in human atrial cells unless unphysiological conditions are used. We speculate that block of NCX with SEA0400 depends on intracellular Na(+) concentration.
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Affiliation(s)
- Torsten Christ
- Department of Pharmacology and Toxicology, Medical Faculty, TU Dresden, Fetscherstr. 74, d-01307 Dresden, Germany; Department of Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
| | - Peter P Kovács
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary.
| | - Karoly Acsai
- MTA-SZTE Cardiovascular Pharmacological Research Group, University of Szeged, Szeged, Hungary.
| | - Michael Knaut
- Clinic for Cardiac Surgery, Heart Center Dresden, Fetscherstrasse 76, 01307 Dresden, Germany.
| | - Thomas Eschenhagen
- Department of Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
| | - Norbert Jost
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary; MTA-SZTE Cardiovascular Pharmacological Research Group, University of Szeged, Szeged, Hungary.
| | - András Varró
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary; MTA-SZTE Cardiovascular Pharmacological Research Group, University of Szeged, Szeged, Hungary.
| | - Erich Wettwer
- Department of Pharmacology and Toxicology, Medical Faculty, TU Dresden, Fetscherstr. 74, d-01307 Dresden, Germany.
| | - Ursula Ravens
- Department of Pharmacology and Toxicology, Medical Faculty, TU Dresden, Fetscherstr. 74, d-01307 Dresden, Germany.
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Major P, Baczkó I, Hiripi L, Odening KE, Juhász V, Kohajda Z, Horváth A, Seprényi G, Kovács M, Virág L, Jost N, Prorok J, Ördög B, Doleschall Z, Nattel S, Varró A, Bősze Z. A novel transgenic rabbit model with reduced repolarization reserve: long QT syndrome caused by a dominant-negative mutation of the KCNE1 gene. Br J Pharmacol 2016; 173:2046-61. [PMID: 27076034 DOI: 10.1111/bph.13500] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Revised: 03/25/2016] [Accepted: 04/01/2016] [Indexed: 01/26/2023] Open
Abstract
BACKGROUND AND PURPOSE The reliable assessment of proarrhythmic risk of compounds under development remains an elusive goal. Current safety guidelines focus on the effects of blocking the KCNH2/HERG ion channel-in tissues and animals with intact repolarization. Novel models with better predictive value are needed that more closely reflect the conditions in patients with cardiac remodelling and reduced repolarization reserve. EXPERIMENTAL APPROACH We have developed a model for the long QT syndrome type-5 in rabbits (LQT5 ) with cardiac-specific overexpression of a mutant (G52R) KCNE1 β-subunit of the channel that carries the slow delayed-rectifier K(+) -current (IKs ). ECG parameters, including short-term variability of the QT interval (STVQT ), a biomarker for proarrhythmic risk, and arrhythmia development were recorded. In vivo, arrhythmia susceptibility was evaluated by i.v. administration of the IKr blocker dofetilide. K(+) currents were measured with the patch-clamp technique. KEY RESULTS Patch-clamp studies in ventricular myocytes isolated from LQT5 rabbits revealed accelerated IKs and IKr deactivation kinetics. At baseline, LQT5 animals exhibited slightly but significantly prolonged heart-rate corrected QT index (QTi) and increased STVQT . Dofetilide provoked Torsade-de-Pointes arrhythmia in a greater proportion of LQT5 rabbits, paralleled by a further increase in STVQT . CONCLUSION AND IMPLICATIONS We have created a novel transgenic LQT5 rabbit model with increased susceptibility to drug-induced arrhythmias that may represent a useful model for testing proarrhythmic potential and for investigations of the mechanisms underlying arrhythmias and sudden cardiac death due to repolarization disturbances.
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Affiliation(s)
- Péter Major
- Rabbit Genome and Biomodel Group, NARIC - Agricultural Biotechnology Institute, Gödöllő, Hungary
| | - István Baczkó
- Department of Pharmacology & Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - László Hiripi
- Rabbit Genome and Biomodel Group, NARIC - Agricultural Biotechnology Institute, Gödöllő, Hungary
| | - Katja E Odening
- Department of Cardiology and Angiology I, Heart Center University of Freiburg, Freiburg, Germany
| | - Viktor Juhász
- Department of Pharmacology & Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - Zsófia Kohajda
- Department of Pharmacology & Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - András Horváth
- Department of Pharmacology & Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - György Seprényi
- Department of Biology, University of Szeged, Szeged, Hungary
| | - Mária Kovács
- Department of Pharmacology & Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - László Virág
- Department of Pharmacology & Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - Norbert Jost
- Department of Pharmacology & Pharmacotherapy, University of Szeged, Szeged, Hungary.,MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary
| | - János Prorok
- Department of Pharmacology & Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - Balázs Ördög
- Department of Pharmacology & Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - Zoltán Doleschall
- Department of Pathogenetics, National Institute of Oncology, Budapest, Hungary
| | - Stanley Nattel
- Department of Medicine, Montreal Heart Institute, Université de Montréal, Canada.,Department of Pharmacology and Therapeutics, McGill University, Montréal, Canada.,Institute of Pharmacology, West German Heart and Vascular Center, Faculty of Medicine, University Duisburg-Essen, Essen, Germany
| | - András Varró
- Department of Pharmacology & Pharmacotherapy, University of Szeged, Szeged, Hungary.,MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary
| | - Zsuzsanna Bősze
- Rabbit Genome and Biomodel Group, NARIC - Agricultural Biotechnology Institute, Gödöllő, Hungary
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50
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Baczkó I, Jost N, Virág L, Bősze Z, Varró A. Rabbit models as tools for preclinical cardiac electrophysiological safety testing: Importance of repolarization reserve. Prog Biophys Mol Biol 2016; 121:157-68. [PMID: 27208697 DOI: 10.1016/j.pbiomolbio.2016.05.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Accepted: 05/01/2016] [Indexed: 01/26/2023]
Abstract
It is essential to more reliably assess the pro-arrhythmic liability of compounds in development. Current guidelines for pre-clinical and clinical testing of drug candidates advocate the use of healthy animals/tissues and healthy individuals and focus on the test compound's ability to block the hERG current and prolong cardiac ventricular repolarization. Also, pre-clinical safety tests utilize several species commonly used in cardiac electrophysiological studies. In this review, important species differences in cardiac ventricular repolarizing ion currents are considered, followed by the discussion on electrical remodeling associated with chronic cardiovascular diseases that leads to altered ion channel and transporter expression and densities in pathological settings. We argue that the choice of species strongly influences experimental outcome and extrapolation of results to human clinical settings. We suggest that based on cardiac cellular electrophysiology, the rabbit is a useful species for pharmacological pro-arrhythmic investigations. In addition to healthy animals and tissues, the use of animal models (e.g. those with impaired repolarization reserve) is suggested that more closely resemble subsets of patients exhibiting increased vulnerability towards the development of ventricular arrhythmias and sudden cardiac death.
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Affiliation(s)
- István Baczkó
- Department of Pharmacology & Pharmacotherapy, University of Szeged, Dóm tér 12., 6720 Szeged, Hungary.
| | - Norbert Jost
- Department of Pharmacology & Pharmacotherapy, University of Szeged, Dóm tér 12., 6720 Szeged, Hungary; MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Dóm tér 12., 6720 Szeged, Hungary
| | - László Virág
- Department of Pharmacology & Pharmacotherapy, University of Szeged, Dóm tér 12., 6720 Szeged, Hungary
| | - Zsuzsanna Bősze
- Rabbit Genome and Biomodel Group, NARIC-Agricultural Biotechnology Institute, 2100 Gödöllő, Hungary
| | - András Varró
- Department of Pharmacology & Pharmacotherapy, University of Szeged, Dóm tér 12., 6720 Szeged, Hungary; MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Dóm tér 12., 6720 Szeged, Hungary
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