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Iness AN, Shah KM, Kukreja RC. Physiological effects of ivabradine in heart failure and beyond. Mol Cell Biochem 2024; 479:2405-2414. [PMID: 37768496 DOI: 10.1007/s11010-023-04862-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Accepted: 09/14/2023] [Indexed: 09/29/2023]
Abstract
Ivabradine is a pharmacologic agent that inhibits the funny current responsible for determining heart rate in the sinoatrial node. Ivabradine's clinical potential has been investigated in the context of heart failure since it is associated with reduced myocardial oxygen demand, enhanced diastolic filling, stroke volume, and coronary perfusion time; however, it is yet to demonstrate definitive mortality benefit. Alternative effects of ivabradine include modulation of the renin-angiotensin-aldosterone system, sympathetic activation, and endothelial function. Here, we review key clinical trials informing the clinical use of ivabradine and explore opportunities for leveraging its potential pleiotropic effects in other diseases, including treatment of hyperadrenergic states and mitigating complications of COVID-19 infection.
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Affiliation(s)
- Audra N Iness
- Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA
| | - Keyur M Shah
- Division of Cardiology, Pauley Heart Center, Internal Medicine, Virginia Commonwealth University, Richmond, VA, USA
| | - Rakesh C Kukreja
- Division of Cardiology, Pauley Heart Center, Internal Medicine, Virginia Commonwealth University, Richmond, VA, USA.
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2
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Saponaro A, Krumbach JH, Chaves-Sanjuan A, Sharifzadeh AS, Porro A, Castelli R, Hamacher K, Bolognesi M, DiFrancesco D, Clarke OB, Thiel G, Moroni A. Structural determinants of ivabradine block of the open pore of HCN4. Proc Natl Acad Sci U S A 2024; 121:e2402259121. [PMID: 38917012 PMCID: PMC11228525 DOI: 10.1073/pnas.2402259121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Accepted: 05/26/2024] [Indexed: 06/27/2024] Open
Abstract
HCN1-4 channels are the molecular determinants of the If/Ih current that crucially regulates cardiac and neuronal cell excitability. HCN dysfunctions lead to sinoatrial block (HCN4), epilepsy (HCN1), and chronic pain (HCN2), widespread medical conditions awaiting subtype-specific treatments. Here, we address the problem by solving the cryo-EM structure of HCN4 in complex with ivabradine, to date the only HCN-specific drug on the market. Our data show ivabradine bound inside the open pore at 3 Å resolution. The structure unambiguously proves that Y507 and I511 on S6 are the molecular determinants of ivabradine binding to the inner cavity, while F510, pointing outside the pore, indirectly contributes to the block by controlling Y507. Cysteine 479, unique to the HCN selectivity filter (SF), accelerates the kinetics of block. Molecular dynamics simulations further reveal that ivabradine blocks the permeating ion inside the SF by electrostatic repulsion, a mechanism previously proposed for quaternary ammonium ions.
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Affiliation(s)
- Andrea Saponaro
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan 20133, Italy
| | - Jan H Krumbach
- Department of Physics, Technische Universität Darmstadt, Darmstadt 64289, Germany
- Department of Biology and Centre for Synthetic Biology, Technische Universität Darmstadt, Darmstadt 64287, Germany
| | | | | | - Alessandro Porro
- Department of Biosciences, University of Milan, Milan 20133, Italy
| | - Roberta Castelli
- Department of Biosciences, University of Milan, Milan 20133, Italy
| | - Kay Hamacher
- Department of Physics, Technische Universität Darmstadt, Darmstadt 64289, Germany
- Department of Biology and Centre for Synthetic Biology, Technische Universität Darmstadt, Darmstadt 64287, Germany
| | | | - Dario DiFrancesco
- Department of Biosciences, University of Milan, Milan 20133, Italy
- Institute of Biophysics-Milan, Consiglio Nazionale delle Ricerche, Milan 20133, Italy
| | - Oliver B Clarke
- Department of Physiology and Cellular Biophysics, Columbia University, New York, NY 10032
- Department of Anesthesiology, Columbia University Irving Medical Center, New York, NY 10032
- Irving Institute for Clinical and Translational Research, Columbia University, New York, NY 10032
| | - Gerhard Thiel
- Department of Biology and Centre for Synthetic Biology, Technische Universität Darmstadt, Darmstadt 64287, Germany
- Department of Biosciences, University of Milan, Milan 20133, Italy
| | - Anna Moroni
- Department of Biosciences, University of Milan, Milan 20133, Italy
- Institute of Biophysics-Milan, Consiglio Nazionale delle Ricerche, Milan 20133, Italy
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3
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Katheria A, Kapoor A, Sahu A, Raut K, Khare H, Khanna R, Kumar S, Garg N, Tewari S. A pilot study evaluating the role of ivabradine for rate control in patients with rheumatic atrial fibrillation. Indian Heart J 2023; 75:376-382. [PMID: 37666416 PMCID: PMC10568053 DOI: 10.1016/j.ihj.2023.08.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Revised: 08/28/2023] [Accepted: 08/29/2023] [Indexed: 09/06/2023] Open
Abstract
OBJECTIVES Ivabradine may have a role in rate control of atrial fibrillation (AF) due to effects on HCN channels in AV node. We studied role of Ivabradine in rate control of rheumatic AF. METHODS 80 patients, rheumatic AF, HR > 100 bpm (age 47 ± 11 yrs, AF duration 6.8 ± 2.9 years, rate 131 ± 16 bpm) on maximally tolerated ββ or CCB's, randomized to Ivabradine or escalated ββ/CCB. Ivabradine started @ 2.5 mg BD; increased to 5 mg BD if inadequate response at 1 week (failure to decrease HR < 10% vs baseline). After Holter at 1 month, dose escalated to 7.5 mg BD if needed. RESULTS Ivabradine resulted in significantly lower HR (81 ± 10 vs 99 ± 9) at 3 months and 6 months (79 ± 8 vs 94 ± 8, p < 0.001). Absolute reduction in HR: 56 ± 15 vs 31 ± 14 bpm and % change in HR: 41 ± 7 vs 24 ± 9%, both p < 0.00001). At 6 months, Ivabradine group had. 1Significantly lower NT Pro BNP (1168 vs 1314 pg/ml), higher 6 min walk distance (410 ± 47 vs 349 ± 54 m, all p < 0.001) 2Better symptom class (EHRA score 1: asymptomatic 84% vs 40%), improvement >1 EHRA class; baseline 60% vs 17% 3Better LA Strain (22.8 ± 2.8% vs 20.6 ± 2.5%) Ivabradine was well tolerated and there was no drug withdrawal. CONCLUSION Our data suggest that Ivabradine can be an option for rate control in rheumatic AF.
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Affiliation(s)
- Arpita Katheria
- Department of Cardiology, Sanjay Gandhi PGIMS, Lucknow, 226014, India.
| | - Aditya Kapoor
- Department of Cardiology, Sanjay Gandhi PGIMS, Lucknow, 226014, India
| | - Ankit Sahu
- Department of Cardiology, Sanjay Gandhi PGIMS, Lucknow, 226014, India
| | - Kamlesh Raut
- Department of Cardiology, Sanjay Gandhi PGIMS, Lucknow, 226014, India
| | - Harshit Khare
- Department of Cardiology, Sanjay Gandhi PGIMS, Lucknow, 226014, India
| | - Roopali Khanna
- Department of Cardiology, Sanjay Gandhi PGIMS, Lucknow, 226014, India
| | - Sudeep Kumar
- Department of Cardiology, Sanjay Gandhi PGIMS, Lucknow, 226014, India
| | - Naveen Garg
- Department of Cardiology, Sanjay Gandhi PGIMS, Lucknow, 226014, India
| | - Satyendra Tewari
- Department of Cardiology, Sanjay Gandhi PGIMS, Lucknow, 226014, India
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4
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Mu L, Liu X, Yu H, Vickstrom CR, Friedman V, Kelly TJ, Hu Y, Su W, Liu S, Mantsch JR, Liu QS. cAMP-mediated upregulation of HCN channels in VTA dopamine neurons promotes cocaine reinforcement. Mol Psychiatry 2023; 28:3930-3942. [PMID: 37845497 PMCID: PMC10730389 DOI: 10.1038/s41380-023-02290-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2023] [Revised: 09/25/2023] [Accepted: 10/03/2023] [Indexed: 10/18/2023]
Abstract
Chronic cocaine exposure induces enduring neuroadaptations that facilitate motivated drug taking. Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels are known to modulate neuronal firing and pacemaker activity in ventral tegmental area (VTA) dopamine neurons. However, it remained unknown whether cocaine self-administration affects HCN channel function and whether HCN channel activity modulates motivated drug taking. We report that rat VTA dopamine neurons predominantly express Hcn3-4 mRNA, while VTA GABA neurons express Hcn1-4 mRNA. Both neuronal types display similar hyperpolarization-activated currents (Ih), which are facilitated by acute increases in cAMP. Acute cocaine application decreases voltage-dependent activation of Ih in VTA dopamine neurons, but not in GABA neurons. Unexpectedly, chronic cocaine self-administration results in enhanced Ih selectively in VTA dopamine neurons. This differential modulation of Ih currents is likely mediated by a D2 autoreceptor-induced decrease in cAMP as D2 (Drd2) mRNA is predominantly expressed in dopamine neurons, whereas D1 (Drd1) mRNA is barely detectable in the VTA. Moreover, chronically decreased cAMP via Gi-DREADD stimulation leads to an increase in Ih in VTA dopamine neurons and enhanced binding of HCN3/HCN4 with tetratricopeptide repeat-containing Rab8b-interacting protein (TRIP8b), an auxiliary subunit that is known to facilitate HCN channel surface trafficking. Finally, we show that systemic injection and intra-VTA infusion of the HCN blocker ivabradine reduces cocaine self-administration under a progressive ratio schedule and produces a downward shift of the cocaine dose-response curve. Our results suggest that cocaine self-administration induces an upregulation of Ih in VTA dopamine neurons, while HCN inhibition reduces the motivation for cocaine intake.
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Affiliation(s)
- Lianwei Mu
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - Xiaojie Liu
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - Hao Yu
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - Casey R Vickstrom
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
- Department of Neurology, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Vladislav Friedman
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - Thomas J Kelly
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - Ying Hu
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - Wantang Su
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
- Department of Exercise Physiology, Beijing Sport University, Beijing, 100084, China
| | - Shuai Liu
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - John R Mantsch
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - Qing-Song Liu
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, WI, 53226, USA.
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5
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Mokrov GV. Multitargeting in cardioprotection: An example of biaromatic compounds. Arch Pharm (Weinheim) 2023; 356:e2300196. [PMID: 37345968 DOI: 10.1002/ardp.202300196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 05/23/2023] [Accepted: 05/26/2023] [Indexed: 06/23/2023]
Abstract
A multitarget drug design approach is actively developing in modern medicinal chemistry and pharmacology, especially with regard to multifactorial diseases such as cardiovascular diseases, cancer, and neurodegenerative diseases. A detailed study of many well-known drugs developed within the single-target approach also often reveals additional mechanisms of their real pharmacological action. One of the multitarget drug design approaches can be the identification of the basic pharmacophore models corresponding to a wide range of the required target ligands. Among such models in the group of cardioprotectors is the linked biaromatic system. This review develops the concept of a "basic pharmacophore" using the biaromatic pharmacophore of cardioprotectors as an example. It presents an analysis of possible biological targets for compounds corresponding to the biaromatic pharmacophore and an analysis of the spectrum of biological targets for the five most known and most studied cardioprotective drugs corresponding to this model, and their involvement in the biological effects of these drugs.
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Arbel Ganon L, Davoodi M, Alexandrovich A, Yaniv Y. Synergy between Membrane Currents Prevents Severe Bradycardia in Mouse Sinoatrial Node Tissue. Int J Mol Sci 2023; 24:ijms24065786. [PMID: 36982861 PMCID: PMC10051777 DOI: 10.3390/ijms24065786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 03/04/2023] [Accepted: 03/13/2023] [Indexed: 03/30/2023] Open
Abstract
Bradycardia is initiated by the sinoatrial node (SAN), which is regulated by a coupled-clock system. Due to the clock coupling, reduction in the 'funny' current (If), which affects SAN automaticity, can be compensated, thus preventing severe bradycardia. We hypothesize that this fail-safe system is an inherent feature of SAN pacemaker cells and is driven by synergy between If and other ion channels. This work aimed to characterize the connection between membrane currents and their underlying mechanisms in SAN cells. SAN tissues were isolated from C57BL mice and Ca2+ signaling was measured in pacemaker cells within them. A computational model of SAN cells was used to understand the interactions between cell components. Beat interval (BI) was prolonged by 54 ± 18% (N = 16) and 30 ± 9% (N = 21) in response to If blockade, by ivabradine, or sodium current (INa) blockade, by tetrodotoxin, respectively. Combined drug application had a synergistic effect, manifested by a BI prolonged by 143 ± 25% (N = 18). A prolongation in the local Ca2+ release period, which reports on the level of crosstalk within the coupled-clock system, was measured and correlated with the prolongation in BI. The computational model predicted that INa increases in response to If blockade and that this connection is mediated by changes in T and L-type Ca2+ channels.
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Affiliation(s)
- Limor Arbel Ganon
- Laboratory of Bioelectric and Bioenergetic Systems, Faculty of Biomedical Engineering, Technion-IIT, Haifa 3200003, Israel
| | - Moran Davoodi
- Laboratory of Bioelectric and Bioenergetic Systems, Faculty of Biomedical Engineering, Technion-IIT, Haifa 3200003, Israel
| | - Alexandra Alexandrovich
- Laboratory of Bioelectric and Bioenergetic Systems, Faculty of Biomedical Engineering, Technion-IIT, Haifa 3200003, Israel
| | - Yael Yaniv
- Laboratory of Bioelectric and Bioenergetic Systems, Faculty of Biomedical Engineering, Technion-IIT, Haifa 3200003, Israel
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Ricci E, Bartolucci C, Severi S. The virtual sinoatrial node: What did computational models tell us about cardiac pacemaking? PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2023; 177:55-79. [PMID: 36374743 DOI: 10.1016/j.pbiomolbio.2022.10.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 10/17/2022] [Accepted: 10/24/2022] [Indexed: 11/11/2022]
Abstract
Since its discovery, the sinoatrial node (SAN) has represented a fascinating and complex matter of research. Despite over a century of discoveries, a full comprehension of pacemaking has still to be achieved. Experiments often produced conflicting evidence that was used either in support or against alternative theories, originating intense debates. In this context, mathematical descriptions of the phenomena underlying the heartbeat have grown in importance in the last decades since they helped in gaining insights where experimental evaluation could not reach. This review presents the most updated SAN computational models and discusses their contribution to our understanding of cardiac pacemaking. Electrophysiological, structural and pathological aspects - as well as the autonomic control over the SAN - are taken into consideration to reach a holistic view of SAN activity.
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Affiliation(s)
- Eugenio Ricci
- Department of Electrical, Electronic, and Information Engineering "Guglielmo Marconi", University of Bologna, Cesena (FC), Italy
| | - Chiara Bartolucci
- Department of Electrical, Electronic, and Information Engineering "Guglielmo Marconi", University of Bologna, Cesena (FC), Italy
| | - Stefano Severi
- Department of Electrical, Electronic, and Information Engineering "Guglielmo Marconi", University of Bologna, Cesena (FC), Italy.
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8
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Mazgaoker S, Weiser-Bitoun I, Brosh I, Binah O, Yaniv Y. cAMP-PKA signaling modulates the automaticity of human iPSC-derived cardiomyocytes. J Gen Physiol 2022; 155:213690. [PMID: 36383232 PMCID: PMC9674091 DOI: 10.1085/jgp.202213153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Accepted: 10/25/2022] [Indexed: 11/17/2022] Open
Abstract
Human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) have been used to screen and characterize drugs and to reveal mechanisms underlying cardiac diseases. However, before hiPSC-CMs can be used as a reliable experimental model, the physiological mechanisms underlying their normal function should be further explored. Accordingly, a major feature of hiPSC-CMs is automaticity, which is regulated by both Ca2+ and membrane clocks. To investigate the mechanisms coupling these clocks, we tested three hypotheses: (1) normal automaticity of spontaneously beating hiPSC-CMs is regulated by local Ca2+ releases (LCRs) and cAMP/PKA-dependent coupling of Ca2+ clock to M clock; (2) the LCR period indicates the level of crosstalk within the coupled-clock system; and (3) perturbing the activity of even one clock can lead to hiPSC-CM-altered automaticity due to diminished crosstalk within the coupled-clock system. By measuring the local and global Ca2+ transients, we found that the LCRs properties are correlated with the spontaneous beat interval. Changes in cAMP-dependent coupling of the Ca2+ and M clocks, caused by a pharmacological intervention that either activates the β-adrenergic or cholinergic receptor or upregulates/downregulates PKA signaling, affected LCR properties, which in turn altered hiPSC-CMs automaticity. Clocks' uncoupling by attenuating the pacemaker current If or the sarcoplasmic reticulum Ca2+ kinetics, decreased hiPSC-CMs beating rate, and prolonged the LCR period. Finally, LCR characteristics of spontaneously beating (at comparable rates) hiPSC-CMs and rabbit SAN are similar. In conclusion, hiPSC-CM automaticity is controlled by the coupled-clock system whose function is mediated by Ca2+-cAMP-PKA signaling.
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Affiliation(s)
- Savyon Mazgaoker
- Laboratory of Bioelectric and Bioenergetic Systems, Faculty of Biomedical Engineering, Technion-Israel Institute of Technology, Haifa, Israel
| | - Ido Weiser-Bitoun
- Laboratory of Bioelectric and Bioenergetic Systems, Faculty of Biomedical Engineering, Technion-Israel Institute of Technology, Haifa, Israel
| | - Inbar Brosh
- Laboratory of Bioelectric and Bioenergetic Systems, Faculty of Biomedical Engineering, Technion-Israel Institute of Technology, Haifa, Israel
| | - Ofer Binah
- Department of Physiology, Biophysics and Systems Biology, Ruth and Bruce Rappaport Faculty of Medicine and Research Institute, TechnionIsrael Institute of Technology, Haifa, Israel
| | - Yael Yaniv
- Laboratory of Bioelectric and Bioenergetic Systems, Faculty of Biomedical Engineering, Technion-Israel Institute of Technology, Haifa, Israel,Correspondence to Yael Yaniv:
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Majgaard J, Skov FG, Kim S, Hjortdal VE, Boedtkjer DMB. Positive chronotropic action of HCN channel antagonism in human collecting lymphatic vessels. Physiol Rep 2022; 10:e15401. [PMID: 35980021 PMCID: PMC9387113 DOI: 10.14814/phy2.15401] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 06/16/2022] [Accepted: 07/09/2022] [Indexed: 06/15/2023] Open
Abstract
Spontaneous action potentials precede phasic contractile activity in human collecting lymphatic vessels. In this study, we investigated the expression of hyperpolarization-activated cyclic nucleotide-gated (HCN) channels in human collecting lymphatics and by pharmacological inhibition ex vivo tested their potential role in controlling contractile function. Spontaneous and agonist-evoked tension changes of isolated thoracic duct and mesenteric lymphatic vessels-obtained from surgical patients with informed consent-were investigated by isometric myography, and ivabradine, ZD7288 or cesium were used to inhibit HCN. Analysis of HCN isoforms by RT-PCR and immunofluorescence revealed HCN2 to be the predominantly expressed mRNA isoform in human thoracic duct and mesenteric lymphatic vessels and HCN2-immunoreactivity confirmed protein expression in both vessel types. However, in functional experiments ex vivo the HCN inhibitors ivabradine, ZD7288, and cesium failed to lower contraction frequency: conversely, all three antagonists induced a positive chronotropic effect with concurrent negative inotropic action, though these effects first occurred at concentrations regarded as supramaximal for HCN inhibition. Based on these results, we conclude that human collecting vessels express HCN channel proteins but under the ex vivo experimental conditions described here HCN channels have little involvement in regulating contraction frequency in human collecting lymphatic vessels. Furthermore, HCN antagonists can produce concentration-dependent positive chronotropic and negative inotropic effects, which are apparently unrelated to HCN antagonism.
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Affiliation(s)
- Jens Majgaard
- Department of BiomedicineAarhus UniversityAarhusDenmark
| | | | - Sukhan Kim
- Department of BiomedicineAarhus UniversityAarhusDenmark
| | - Vibeke Elisabeth Hjortdal
- Department of Clinical MedicineAarhus UniversityAarhusDenmark
- Department of Cardiothoracic and Vascular SurgeryAarhus University HospitalAarhusDenmark
| | - Donna M. B. Boedtkjer
- Department of BiomedicineAarhus UniversityAarhusDenmark
- Department of Clinical MedicineAarhus UniversityAarhusDenmark
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10
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Hackl B, Lukacs P, Ebner J, Pesti K, Haechl N, Földi MC, Lilliu E, Schicker K, Kubista H, Stary-Weinzinger A, Hilber K, Mike A, Todt H, Koenig X. The Bradycardic Agent Ivabradine Acts as an Atypical Inhibitor of Voltage-Gated Sodium Channels. Front Pharmacol 2022; 13:809802. [PMID: 35586063 PMCID: PMC9108390 DOI: 10.3389/fphar.2022.809802] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 02/24/2022] [Indexed: 12/19/2022] Open
Abstract
Background and purpose: Ivabradine is clinically administered to lower the heart rate, proposedly by inhibiting hyperpolarization-activated cyclic nucleotide-gated cation channels in the sinoatrial node. Recent evidence suggests that voltage-gated sodium channels (VGSC) are inhibited within the same concentration range. VGSCs are expressed within the sinoatrial node and throughout the conduction system of the heart. A block of these channels thus likely contributes to the established and newly raised clinical indications of ivabradine. We, therefore, investigated the pharmacological action of ivabradine on VGSCs in sufficient detail in order to gain a better understanding of the pro- and anti-arrhythmic effects associated with the administration of this drug. Experimental Approach: Ivabradine was tested on VGSCs in native cardiomyocytes isolated from mouse ventricles and the His-Purkinje system and on human Nav1.5 in a heterologous expression system. We investigated the mechanism of channel inhibition by determining its voltage-, frequency-, state-, and temperature-dependence, complemented by a molecular drug docking to the recent Nav1.5 cryoEM structure. Automated patch-clamp experiments were used to investigate ivabradine-mediated changes in Nav1.5 inactivation parameters and inhibition of different VGSC isoforms. Key results: Ivabradine inhibited VGSCs in a voltage- and frequency-dependent manner, but did not alter voltage-dependence of activation and fast inactivation, nor recovery from fast inactivation. Cardiac (Nav1.5), neuronal (Nav1.2), and skeletal muscle (Nav1.4) VGSC isoforms were inhibited by ivabradine within the same concentration range, as were sodium currents in native cardiomyocytes isolated from the ventricles and the His-Purkinje system. Molecular drug docking suggested an interaction of ivabradine with the classical local anesthetic binding site. Conclusion and Implications: Ivabradine acts as an atypical inhibitor of VGSCs. Inhibition of VGSCs likely contributes to the heart rate lowering effect of ivabradine, in particular at higher stimulation frequencies and depolarized membrane potentials, and to the observed slowing of intra-cardiac conduction. Inhibition of VGSCs in native cardiomyocytes and across channel isoforms may provide a potential basis for the anti-arrhythmic potential as observed upon administration of ivabradine.
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Affiliation(s)
- Benjamin Hackl
- Department of Neurophysiology and Neuropharmacology, Medical University of Vienna, Vienna, Austria
| | - Peter Lukacs
- ELKH, Plant Protection Institute, Centre for Agricultural Research, Martonvásár, Hungary
| | - Janine Ebner
- Department of Neurophysiology and Neuropharmacology, Medical University of Vienna, Vienna, Austria
| | - Krisztina Pesti
- Department of Biochemistry, ELTE Eötvös Loránd University, Budapest, Hungary
- Semmelweis University, School of Ph.D. Studies, Budapest, Hungary
| | - Nicholas Haechl
- Department of Neurophysiology and Neuropharmacology, Medical University of Vienna, Vienna, Austria
| | - Mátyás C Földi
- ELKH, Plant Protection Institute, Centre for Agricultural Research, Martonvásár, Hungary
- Department of Biochemistry, ELTE Eötvös Loránd University, Budapest, Hungary
| | - Elena Lilliu
- Department of Neurophysiology and Neuropharmacology, Medical University of Vienna, Vienna, Austria
| | - Klaus Schicker
- Department of Neurophysiology and Neuropharmacology, Medical University of Vienna, Vienna, Austria
| | - Helmut Kubista
- Department of Neurophysiology and Neuropharmacology, Medical University of Vienna, Vienna, Austria
| | | | - Karlheinz Hilber
- Department of Neurophysiology and Neuropharmacology, Medical University of Vienna, Vienna, Austria
| | - Arpad Mike
- ELKH, Plant Protection Institute, Centre for Agricultural Research, Martonvásár, Hungary
- Department of Biochemistry, ELTE Eötvös Loránd University, Budapest, Hungary
| | - Hannes Todt
- Department of Neurophysiology and Neuropharmacology, Medical University of Vienna, Vienna, Austria
| | - Xaver Koenig
- Department of Neurophysiology and Neuropharmacology, Medical University of Vienna, Vienna, Austria
- *Correspondence: Xaver Koenig,
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11
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Eriksson ANM, Rigaud C, Krasnov A, Wincent E, Vehniäinen ER. Exposure to retene, fluoranthene, and their binary mixture causes distinct transcriptomic and apical outcomes in rainbow trout (Oncorhynchus mykiss) yolk sac alevins. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2022; 244:106083. [PMID: 35085954 DOI: 10.1016/j.aquatox.2022.106083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 01/11/2022] [Accepted: 01/18/2022] [Indexed: 06/14/2023]
Abstract
Polycyclic aromatic hydrocarbons (PAHs) are widely spread environmental contaminants which affect developing organisms. It is known that improper activation of the aryl hydrocarbon receptor (AhR) by some PAHs contributes to toxicity, while other PAHs can disrupt cellular membrane function. The exact downstream mechanisms of AhR activation remain unresolved, especially with regard to cardiotoxicity. By exposing newly hatched rainbow trout alevins (Oncorhynchus mykiss) semi-statically to retene (32 µg l-1; AhR agonist), fluoranthene (50 µg l-1; weak AhR agonist and CYP1a inhibitor) and their binary mixture for 1, 3, 7 and 14 days, we aimed to uncover novel mechanisms of cardiotoxicity using a targeted microarray approach. At the end of the exposure, standard length, yolk area, blue sac disease (BSD) index and PAH body burden were measured, while the hearts were prepared for microarray analysis. Each exposure produced a unique toxicity profile. We observed that retene and the mixture, but not fluoranthene, significantly reduced growth by Day 14 compared to the control, while exposure to the mixture increased the BSD-index significantly from Day 3 onward. Body burden profiles were PAH-specific and correlated well with the exposure-specific upregulations of genes encoding for phase I and II enzymes. Exposure to the mixture over-represented pathways related to growth, amino acid and xenobiotic metabolism and oxidative stress responses. Alevins exposed to the individual PAHs displayed over-represented pathways involved in receptor signaling: retene downregulated genes with a role in G-protein signaling, while fluoranthene upregulated those involved in GABA signaling. Furthermore, exposure to retene and fluoranthene altered the expression of genes encoding for proteins involved in calcium- and potassium ion channels, which suggests affected heart structure and function. This study provides deeper understanding of the complexity of PAH toxicity and the necessity of investigating PAHs as mixtures and not as individual components.
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Affiliation(s)
- Andreas N M Eriksson
- Department of Biological and Environmental Sciences, University of Jyväskylä, P.O. Box 35, Jyväskylä FI-40014, Finland.
| | - Cyril Rigaud
- Department of Biological and Environmental Sciences, University of Jyväskylä, P.O. Box 35, Jyväskylä FI-40014, Finland
| | - Aleksei Krasnov
- Fisheries and Aquaculture Research, Norwegian Institute of Food, Ås, Norway
| | - Emma Wincent
- Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Eeva-Riikka Vehniäinen
- Department of Biological and Environmental Sciences, University of Jyväskylä, P.O. Box 35, Jyväskylä FI-40014, Finland
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12
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Takahara A, Kawakami S, Aimoto M, Nagasawa Y. Torsadogenic Potential of HCN Channel Blocker Ivabradine Assessed in the Rabbit Proarrhythmia Model. Biol Pharm Bull 2021; 44:1796-1799. [PMID: 34719656 DOI: 10.1248/bpb.b21-00605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Torsadogenic effects of ivabradine, an inhibitor of hyperpolarization-activated cyclic nucleotide-gated (HCN) channels, were assessed in an in vivo proarrhythmia model of acute atrioventricular block rabbit. Ivabradine at 0.01, 0.1, and 1 mg/kg was intravenously administered to isoflurane-anesthetized rabbits (n = 5) in the stable idioventricular rhythm. Ivabradine at 0.01 and 0.1 mg/kg hardly affected the atrial and ventricular automaticity, QT interval, or the monophasic action potential duration of the ventricle. Additionally administred ivabradine at 1 mg/kg decreased the atrial and ventricular rate significantly but increased the QT interval and duration of the monophasic action potential. Meanwhile, torsade de pointes arrhythmias were detected in 1 out of 5 animals and in 2 out of 5 animals after the administration of 0.1 and 1 mg/kg, respectively. Importantly, torsade de pointes arrhythmias could be observed only in 2 rabbits showing more potent suppressive effects on ventricular automaticity. These results suggest that the torsadogenic potential of ivabradine may become evident when its expected bradycardic action appears more excessively.
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Affiliation(s)
- Akira Takahara
- Department of Pharmacology and Therapeutics, Faculty of Pharmaceutical Sciences, Toho University
| | - Satoshi Kawakami
- Department of Pharmacology and Therapeutics, Faculty of Pharmaceutical Sciences, Toho University
| | - Megumi Aimoto
- Department of Pharmacology and Therapeutics, Faculty of Pharmaceutical Sciences, Toho University
| | - Yoshinobu Nagasawa
- Department of Pharmacology and Therapeutics, Faculty of Pharmaceutical Sciences, Toho University
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13
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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: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [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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14
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Bai X, Wang K, Boyett MR, Hancox JC, Zhang H. The Functional Role of Hyperpolarization Activated Current ( I f) on Cardiac Pacemaking in Human vs. in the Rabbit Sinoatrial Node: A Simulation and Theoretical Study. Front Physiol 2021; 12:582037. [PMID: 34489716 PMCID: PMC8417414 DOI: 10.3389/fphys.2021.582037] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Accepted: 07/23/2021] [Indexed: 01/01/2023] Open
Abstract
The cardiac hyperpolarization-activated “funny” current (If), which contributes to sinoatrial node (SAN) pacemaking, has a more negative half-maximal activation voltage and smaller fully-activated macroscopic conductance in human than in rabbit SAN cells. The consequences of these differences for the relative roles of If in the two species, and for their responses to the specific bradycardic agent ivabradine at clinical doses have not been systematically explored. This study aims to address these issues, through incorporating rabbit and human If formulations developed by Fabbri et al. into the Severi et al. model of rabbit SAN cells. A theory was developed to correlate the effect of If reduction with the total inward depolarising current (Itotal) during diastolic depolarization. Replacing the rabbit If formulation with the human one increased the pacemaking cycle length (CL) from 355 to 1,139 ms. With up to 20% If reduction (a level close to the inhibition of If by ivabradine at clinical concentrations), a modest increase (~5%) in the pacemaking CL was observed with the rabbit If formulation; however, the effect was doubled (~12.4%) for the human If formulation, even though the latter has smaller If density. When the action of acetylcholine (ACh, 0.1 nM) was considered, a 20% If reduction markedly increased the pacemaking CL by 37.5% (~27.3% reduction in the pacing rate), which is similar to the ivabradine effect at clinical concentrations. Theoretical analysis showed that the resultant increase of the pacemaking CL is inversely proportional to the magnitude of Itotal during diastolic depolarization phase: a smaller If in the model resulted in a smaller Itotal amplitude, resulting in a slower pacemaking rate; and the same reduction in If resulted in a more significant change of CL in the cell model with a smaller Itotal. This explained the mechanism by which a low dose of ivabradine slows pacemaking rate more in humans than in the rabbit. Similar results were seen in the Fabbri et al. model of human SAN cells, suggesting our observations are model-independent. Collectively, the results of study explain why low dose ivabradine at clinically relevant concentrations acts as an effective bradycardic agent in modulating human SAN pacemaking.
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Affiliation(s)
- Xiangyun Bai
- Biological Physics Group, Department of Physics and Astronomy, The University of Manchester, Manchester, United Kingdom.,School of Computer Science and Technology, Xi'an University of Posts and Telecommunications, Xi'an, China.,School of Computer Science and Technology, Harbin Institute of Technology, Harbin, China
| | - Kuanquan Wang
- School of Computer Science and Technology, Harbin Institute of Technology, Harbin, China
| | - Mark R Boyett
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, København, Denmark
| | - Jules C Hancox
- Biological Physics Group, Department of Physics and Astronomy, The University of Manchester, Manchester, United Kingdom.,School of Physiology, Pharmacology and Neuroscience, Biomedical Sciences Building, University Walk, Bristol, United Kingdom
| | - Henggui Zhang
- Biological Physics Group, Department of Physics and Astronomy, The University of Manchester, Manchester, United Kingdom.,Peng Cheng Laboratory, Shenzhen, China.,Key Laboratory of Medical Electrophysiology of Ministry of Education, Medical Electrophysiological Key Laboratory of Sichuan, Institute of Cardiovascular Research, Southwest Medical University, Luzhou, China
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15
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Benzoni P, Bertoli G, Giannetti F, Piantoni C, Milanesi R, Pecchiari M, Barbuti A, Baruscotti M, Bucchi A. The funny current: Even funnier than 40 years ago. Uncanonical expression and roles of HCN/f channels all over the body. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2021; 166:189-204. [PMID: 34400215 DOI: 10.1016/j.pbiomolbio.2021.08.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 06/25/2021] [Accepted: 08/09/2021] [Indexed: 12/25/2022]
Abstract
Discovered some 40 years ago, the If current has since been known as the "pacemaker" current due to its role in the initiation and modulation of the heartbeat and of neuronal excitability. But this is not all, the funny current keeps entertaining the researchers; indeed, several data discovering novel and uncanonical roles of f/HCN channel are quickly accumulating. In the present review, we provide an overview of the expression and cellular functions of HCN/f channels in a variety of systems/organs, and particularly in sour taste transduction, hormones secretion, activation of astrocytes and microglia, inhibition of osteoclastogenesis, renal ammonium excretion, and peristalsis in the gastrointestinal and urine systems. We also analyzed the role of HCN channels in sustaining cellular respiration in mitochondria and their participation to mitophagy under specific conditions. The relevance of HCN currents in undifferentiated cells, and specifically in the control of stem cell cycle and in bioelectrical signals driving left/right asymmetry during zygote development, is also considered. Finally, we present novel data concerning the expression of HCN mRNA in human leukocytes. We can thus conclude that the emerging evidence presented in this review clearly points to an increasing interest and importance of the "funny" current that goes beyond its role in cardiac sinoatrial and neuronal excitability regulation.
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Affiliation(s)
- Patrizia Benzoni
- The Cell Physiology MiLab, Department of Biosciences, Università degli Studi di Milano, Via G. Celoria 26, 20133, Milan, Italy
| | - Giorgia Bertoli
- The Cell Physiology MiLab, Department of Biosciences, Università degli Studi di Milano, Via G. Celoria 26, 20133, Milan, Italy
| | - Federica Giannetti
- The Cell Physiology MiLab, Department of Biosciences, Università degli Studi di Milano, Via G. Celoria 26, 20133, Milan, Italy
| | - Chiara Piantoni
- The Cell Physiology MiLab, Department of Biosciences, Università degli Studi di Milano, Via G. Celoria 26, 20133, Milan, Italy; Present Address: Institute of Neurophysiology, Hannover Medical School, Carl-Neuberg-Str.1, 30625, Hannover, Germany
| | - Raffaella Milanesi
- The Cell Physiology MiLab, Department of Biosciences, Università degli Studi di Milano, Via G. Celoria 26, 20133, Milan, Italy; Present Address: Dipartimento di Medicina Veterinaria, Università degli Studi di Milano, Via Dell'Università 6, 26900, Lodi, Italy
| | - Matteo Pecchiari
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Via L. Mangiagalli 32, 20133, Milan, Italy
| | - Andrea Barbuti
- The Cell Physiology MiLab, Department of Biosciences, Università degli Studi di Milano, Via G. Celoria 26, 20133, Milan, Italy
| | - Mirko Baruscotti
- The Cell Physiology MiLab, Department of Biosciences, Università degli Studi di Milano, Via G. Celoria 26, 20133, Milan, Italy
| | - Annalisa Bucchi
- The Cell Physiology MiLab, Department of Biosciences, Università degli Studi di Milano, Via G. Celoria 26, 20133, Milan, Italy.
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16
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The HCN channel as a pharmacological target: Why, where, and how to block it. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2021; 166:173-181. [PMID: 34303730 DOI: 10.1016/j.pbiomolbio.2021.07.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 06/22/2021] [Accepted: 07/20/2021] [Indexed: 12/19/2022]
Abstract
Hyperpolarization-activated, cyclic nucleotide-gated (HCN) channels, expressed in a variety of cell types and in all tissues, control excitation and rhythm. Since their discovery in neurons and cardiac pacemaker cells, they attracted the attention of medicinal chemistry and pharmacology as novel targets to shape (patho)physiological mechanisms. To date, ivabradine represents the first-in-class drug as specific bradycardic agent in cardiac diseases; however, new applications are emerging in parallel with the demonstration of the involvement of different HCN isoforms in central and peripheral nervous system. Hence, the possibility to target specific isoforms represents an attractive development in this field; indeed, HCN1, HCN2 or HCN4 specific blockers have shown promising features in vitro and in vivo, with remarkable pharmacological differences likely depending on the diverse functional role and tissue distribution. Here, we show a recently developed compound with high potency as HCN2-HCN4 blocker; because of its unique profile, this compound may deserve further investigation.
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17
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Peters CH, Liu PW, Morotti S, Gantz SC, Grandi E, Bean BP, Proenza C. Bidirectional flow of the funny current (I f) during the pacemaking cycle in murine sinoatrial node myocytes. Proc Natl Acad Sci U S A 2021; 118:e2104668118. [PMID: 34260402 PMCID: PMC8285948 DOI: 10.1073/pnas.2104668118] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Sinoatrial node myocytes (SAMs) act as cardiac pacemaker cells by firing spontaneous action potentials (APs) that initiate each heartbeat. The funny current (If) is critical for the generation of these spontaneous APs; however, its precise role during the pacemaking cycle remains unresolved. Here, we used the AP-clamp technique to quantify If during the cardiac cycle in mouse SAMs. We found that If is persistently active throughout the sinoatrial AP, with surprisingly little voltage-dependent gating. As a consequence, it carries both inward and outward current around its reversal potential of -30 mV. Despite operating at only 2 to 5% of its maximal conductance, If carries a substantial fraction of both depolarizing and repolarizing net charge movement during the firing cycle. We also show that β-adrenergic receptor stimulation increases the percentage of net depolarizing charge moved by If, consistent with a contribution of If to the fight-or-flight increase in heart rate. These properties were confirmed by heterologously expressed HCN4 channels and by mathematical models of If Modeling further suggested that the slow rates of activation and deactivation of the HCN4 isoform underlie the persistent activity of If during the sinoatrial AP. These results establish a new conceptual framework for the role of If in pacemaking, in which it operates at a very small fraction of maximal activation but nevertheless drives membrane potential oscillations in SAMs by providing substantial driving force in both inward and outward directions.
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Affiliation(s)
- Colin H Peters
- Department of Physiology and Biophysics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045
| | - Pin W Liu
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115
| | - Stefano Morotti
- Department of Pharmacology, University of California, Davis, CA 95616
| | - Stephanie C Gantz
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115
- Department of Molecular Physiology and Biophysics, Carver College of Medicine, University of Iowa, Iowa City, IA 52242
| | - Eleonora Grandi
- Department of Pharmacology, University of California, Davis, CA 95616
| | - Bruce P Bean
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115
| | - Catherine Proenza
- Department of Physiology and Biophysics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045;
- Department of Medicine, Division of Cardiology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045
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18
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Saleem U, van Meer BJ, Katili PA, Mohd Yusof NAN, Mannhardt I, Garcia AK, Tertoolen L, de Korte T, Vlaming MLH, McGlynn K, Nebel J, Bahinski A, Harris K, Rossman E, Xu X, Burton FL, Smith GL, Clements P, Mummery CL, Eschenhagen T, Hansen A, Denning C. Blinded, Multicenter Evaluation of Drug-induced Changes in Contractility Using Human-induced Pluripotent Stem Cell-derived Cardiomyocytes. Toxicol Sci 2021; 176:103-123. [PMID: 32421822 PMCID: PMC7357169 DOI: 10.1093/toxsci/kfaa058] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Animal models are 78% accurate in determining whether drugs will alter contractility of the human heart. To evaluate the suitability of human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) for predictive safety pharmacology, we quantified changes in contractility, voltage, and/or Ca2+ handling in 2D monolayers or 3D engineered heart tissues (EHTs). Protocols were unified via a drug training set, allowing subsequent blinded multicenter evaluation of drugs with known positive, negative, or neutral inotropic effects. Accuracy ranged from 44% to 85% across the platform-cell configurations, indicating the need to refine test conditions. This was achieved by adopting approaches to reduce signal-to-noise ratio, reduce spontaneous beat rate to ≤ 1 Hz or enable chronic testing, improving accuracy to 85% for monolayers and 93% for EHTs. Contraction amplitude was a good predictor of negative inotropes across all the platform-cell configurations and of positive inotropes in the 3D EHTs. Although contraction- and relaxation-time provided confirmatory readouts forpositive inotropes in 3D EHTs, these parameters typically served as the primary source of predictivity in 2D. The reliance of these “secondary” parameters to inotropy in the 2D systems was not automatically intuitive and may be a quirk of hiPSC-CMs, hence require adaptations in interpreting the data from this model system. Of the platform-cell configurations, responses in EHTs aligned most closely to the free therapeutic plasma concentration. This study adds to the notion that hiPSC-CMs could add value to drug safety evaluation.
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Affiliation(s)
- Umber Saleem
- Department of Experimental Pharmacology and Toxicology, University Medical Center Hamburg Eppendorf, 20246 Hamburg, and DZHK (German Center for Cardiovascular Research), Partner Site, Hamburg/Kiel/Lübeck, Germany
| | - Berend J van Meer
- Department of Anatomy and Embryology, Leiden University Medical Center, 2333 ZD, Leiden, The Netherlands
| | - Puspita A Katili
- Department of Stem Cell Biology, University of Nottingham, University Park, Nottingham NG7 2RD, UK
| | - Nurul A N Mohd Yusof
- Department of Stem Cell Biology, University of Nottingham, University Park, Nottingham NG7 2RD, UK
| | - Ingra Mannhardt
- Department of Experimental Pharmacology and Toxicology, University Medical Center Hamburg Eppendorf, 20246 Hamburg, and DZHK (German Center for Cardiovascular Research), Partner Site, Hamburg/Kiel/Lübeck, Germany
| | - Ana Krotenberg Garcia
- Department of Anatomy and Embryology, Leiden University Medical Center, 2333 ZD, Leiden, The Netherlands
| | - Leon Tertoolen
- Department of Anatomy and Embryology, Leiden University Medical Center, 2333 ZD, Leiden, The Netherlands
| | - Tessa de Korte
- Department of Anatomy and Embryology, Leiden University Medical Center, 2333 ZD, Leiden, The Netherlands.,Ncardia, 2333 BD, Leiden, The Netherlands
| | | | - Karen McGlynn
- Clyde Biosciences Ltd, Biocity Scotland, Newhouse, Lanarkshire ML1 5HU, UK
| | - Jessica Nebel
- Department of Experimental Pharmacology and Toxicology, University Medical Center Hamburg Eppendorf, 20246 Hamburg, and DZHK (German Center for Cardiovascular Research), Partner Site, Hamburg/Kiel/Lübeck, Germany
| | | | | | - Eric Rossman
- GlaxoSmithKline, Collegeville, Pennsylvania 19426
| | - Xiaoping Xu
- GlaxoSmithKline, Collegeville, Pennsylvania 19426
| | - Francis L Burton
- Clyde Biosciences Ltd, Biocity Scotland, Newhouse, Lanarkshire ML1 5HU, UK.,Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow G12 8QQ, UK
| | - Godfrey L Smith
- Clyde Biosciences Ltd, Biocity Scotland, Newhouse, Lanarkshire ML1 5HU, UK.,Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow G12 8QQ, UK
| | - Peter Clements
- GlaxoSmithKline, David Jack Centre for R&D, Ware, Hertfordshire SG12 0DP, UK
| | - Christine L Mummery
- Department of Anatomy and Embryology, Leiden University Medical Center, 2333 ZD, Leiden, The Netherlands.,Department Applied Stem Cell Technologies, University of Twente, 7500 EA Enschede, The Netherlands
| | - Thomas Eschenhagen
- Department of Experimental Pharmacology and Toxicology, University Medical Center Hamburg Eppendorf, 20246 Hamburg, and DZHK (German Center for Cardiovascular Research), Partner Site, Hamburg/Kiel/Lübeck, Germany
| | - Arne Hansen
- Department of Experimental Pharmacology and Toxicology, University Medical Center Hamburg Eppendorf, 20246 Hamburg, and DZHK (German Center for Cardiovascular Research), Partner Site, Hamburg/Kiel/Lübeck, Germany
| | - Chris Denning
- Department of Stem Cell Biology, University of Nottingham, University Park, Nottingham NG7 2RD, UK
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19
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Moïse NS, Brewer FC, Flanders WH, Kornreich BG, Otani NF. Insights into sinus arrhythmia of the dog: Acetylcholine perfusion of canine right atrium results in beat-to-beat patterns that mimic sinus arrhythmia supporting exit block in the sinoatrial conduction pathways. Vet J 2021; 272:105651. [PMID: 33745806 DOI: 10.1016/j.tvjl.2021.105651] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 02/28/2021] [Accepted: 03/01/2021] [Indexed: 12/19/2022]
Abstract
Sinus arrhythmia of the dog is unique because of the pronounced alternating beat-to-beat intervals. The clustering of these short (faster rates) and long (slower rates) intervals is not just influenced by autonomic input from breathing; sinus arrhythmia can persist in the panting or apneic dog. The multiplicity of central and peripheral influences on the sinus node complicates the unraveling of the mechanisms of sinus arrhythmia. Studies of the sinus node suggest that acetylcholine can slow cellular depolarization and block sinoatrial conduction. Electrocardiographic monitoring of the dog supports this notion in that abrupt bifurcation into short and long intervals develop at lower heart rates. We sought to determine whether this phenomenon could be recapitulated in canine atrial preparations perfused with acetylcholine and whether selective pharmacologic blockade of the voltage and calcium clocks could provide insight into its mechanism. Spontaneous beat to beat (A-A) intervals were obtained from monophasic action potential recordings of perfused canine right atrial preparations before and during perfusion with acetylcholine (2-5 μM). The calcium clock was blocked with ryanodine (2-3 μM). The membrane clock was blocked with diltiazem hydrochloride (ICa,L blocker; 0.25 μM) and ZD7288 (If blocker; 3 μM). Hyperpolarization was hindered by blockade of IK,Ado/IK,Ach with tertiapin Q (100 nM) before and during acetylcholine perfusion. Acetylcholine resulted in beat clusters similar to those seen in sinus arrhythmia of the dog. Beat clusters were consistent with intermittent 2:1 and 3:1 sinoatrial conduction block. Tertiapin Q abolished this patterning suggesting a role of IK,Ado/IK,ACh in the mechanism of these acetylcholine-induced beat-to-beat patterns.
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Affiliation(s)
- N S Moïse
- Section of Cardiology, Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA.
| | - F C Brewer
- California Pet Cardiology, Long Beach, CA 90808, USA
| | - W H Flanders
- Department of Physics, University of Washington, Seattle, WA 98195, USA
| | - B G Kornreich
- Section of Cardiology, Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
| | - N F Otani
- School of Mathematical Sciences, College of Science, Rochester Institute of Technology, Rochester, NY 14623, USA
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20
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Effectiveness of point-of-care oral ivabradine for cardiac computed tomography. J Cardiovasc Comput Tomogr 2020; 15:226-231. [PMID: 33039320 DOI: 10.1016/j.jcct.2020.09.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 08/29/2020] [Accepted: 09/15/2020] [Indexed: 11/22/2022]
Abstract
BACKGROUND Coronary CT angiography (CCTA) is increasing seen as a first line investigation in patients with suspected coronary artery disease. Heart-rate control improves the image quality and diagnostic accuracy of CCTA. Typically, beta-blockers are administered to induce sinus bradycardia. Sinus bradycardia may also be induced by ivabradine. We hypothesized that in a real-world population ivabradine would be an effective alternative to metoprolol at heart rate lowering for CCTA. METHODS This was a retrospective analysis of consecutive patients who were exposed to an ivabradine-based (IB) versus a metoprolol-only (MO) protocol to achieve a target heart rate </ = 65bpm. Hemodynamic responses to both strategies were compared along with differences in cost and the time expired from medication administration to CCTA. RESULTS 5955 consecutive patients were included in the analysis: 3211 were imaged during an era of a metoprolol only strategy (MO) and 2744 CCTA following an ivabradine based (IB) strategy. 2676 patients had heart rates >65 and received heart-rate lowering medication: 1958 patients had MO, and 718 received IB protocol. Target heart rate of </ = 65bpm was achieved in 77% of MO and 89% of IB patients (p < 0.01). The time from initial medication administration to CCTA was longer in the IB versus MO patients (77 versus 48 min, p < 0.01). CONCLUSIONS Introduction of a novel single dose ivabradine-based protocol to control heart rate for CCTA was more successful in achieving target heart rate than a metoprolol-only strategy. The use of ivabradine however incurred a 1.6-fold increase in the time delay from medication administration and imaging compared to a metoprolol only protocol.
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21
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Abstract
Ivabradine is a pure heart-rate lowering drug that is nowadays used, accordingly to the last ESC Guidelines, to reduce mortality and heart failure (HF) hospitalization in patients with HF with reduced ejection fraction and in symptomatic patiens with inappropriate sinus tachycardia. Moreover, interesting effect of ivabradine on endothelial and myocardial function and on oxidative stress and inflamation pathways are progressively emerging. The aim of this paper is to highlight newer evidences about ivabradine effect (and consequently possible future application of the drug) in pathological settings different from guidelines-based clinical practice.
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Affiliation(s)
- Lucia Dallapellegrina
- Cardio-Thoracic Department, ASST Spedali Civili, Piazzale Spedali Civili 1, Brescia, 25128, Italy.,Department of Medical and Surgical Specialties, Cardiology Unit, Radiological Sciences and Public Health, University of Brescia, Italy
| | - Edoardo Sciatti
- Department of Medical and Surgical Specialties, Cardiology Unit, Radiological Sciences and Public Health, University of Brescia, Brescia, Italy.,Cardio-Thoracic Department, ASST Spedali Civili, Brescia, Italy
| | - Enrico Vizzardi
- Department of Medical and Surgical Specialties, Cardiology Unit, Radiological Sciences and Public Health, University of Brescia, Brescia, Italy.,Cardio-Thoracic Department, ASST Spedali Civili, Brescia, Italy
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22
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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] [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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23
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Saleem U, Mannhardt I, Braren I, Denning C, Eschenhagen T, Hansen A. Force and Calcium Transients Analysis in Human Engineered Heart Tissues Reveals Positive Force-Frequency Relation at Physiological Frequency. Stem Cell Reports 2020; 14:312-324. [PMID: 31956082 PMCID: PMC7013237 DOI: 10.1016/j.stemcr.2019.12.011] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Revised: 12/17/2019] [Accepted: 12/18/2019] [Indexed: 01/29/2023] Open
Abstract
Force measurements in ex vivo and engineered heart tissues are well established. Analysis of calcium transients (CaT) is complementary to force, and the combined analysis is meaningful to the study of cardiomyocyte biology and disease. This article describes a model of human induced pluripotent stem cell cardiomyocyte-derived engineered heart tissues (hiPSC-CM EHTs) transduced with the calcium sensor GCaMP6f followed by sequential analysis of force and CaT. Average peak analysis demonstrated the temporal sequence of the CaT preceding the contraction twitch. The pharmacological relevance of the test system was demonstrated with inotropic indicator compounds. Force-frequency relationship was analyzed in the presence of ivabradine (300 nM), which reduced spontaneous frequency and unmasked a positive correlation of force and CaT at physiological human heart beating frequency with stimulation frequency between 0.75 and 2.5 Hz (force +96%; CaT +102%). This work demonstrates the usefulness of combined force/CaT analysis and demonstrates a positive force-frequency relationship in hiPSC-CM EHTs. Analysis of calcium transients and force in engineered heart tissues Accurate replications of drug effects on calcium transients and force analysis Positive force- and calcium transients-frequency relationship Reverse correlation between omecamtiv mecarbil's inotropic effect and frequency
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Affiliation(s)
- Umber Saleem
- Department of Experimental Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; German Center for Cardiovascular Research (DZHK), Partner Site Hamburg/Kiel/Lübeck, 20246 Hamburg, Germany
| | - Ingra Mannhardt
- Department of Experimental Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; German Center for Cardiovascular Research (DZHK), Partner Site Hamburg/Kiel/Lübeck, 20246 Hamburg, Germany
| | - Ingke Braren
- Vector Facility, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; German Center for Cardiovascular Research (DZHK), Partner Site Hamburg/Kiel/Lübeck, 20246 Hamburg, Germany
| | - Chris Denning
- Wolfson Centre for Stem Cells, Tissue Engineering and Modelling, Centre for Biomolecular Sciences, University of Nottingham, University Park, Nottingham NG7 2RD, UK
| | - Thomas Eschenhagen
- Department of Experimental Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; German Center for Cardiovascular Research (DZHK), Partner Site Hamburg/Kiel/Lübeck, 20246 Hamburg, Germany
| | - Arne Hansen
- Department of Experimental Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; German Center for Cardiovascular Research (DZHK), Partner Site Hamburg/Kiel/Lübeck, 20246 Hamburg, Germany.
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24
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The Effect of Ivabradine on the Human Atrial Myocardial Contractility in an In Vitro Study. Cardiol Res Pract 2019; 2019:7512318. [PMID: 31827920 PMCID: PMC6885252 DOI: 10.1155/2019/7512318] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2019] [Revised: 09/19/2019] [Accepted: 10/09/2019] [Indexed: 11/18/2022] Open
Abstract
Purpose Ivabradine has emerged as a new antiarrhythmic agent that could compete with the traditional ones, such as beta-blockers. This experimental study aims to ascertain whether ivabradine directly interferes with the myocardial contractility in an in vitro environment. Methods Myocardial tissues from the right atrial appendages of patients undergoing cardiac surgery were dissected to obtain 40 specimens from 20 patients (length: 3 mm), which were exposed to electrical impulses at a frequency of 75 bpm for 30 min to reach a steady state. Specimens were then categorised into four groups (each including five patients). The first group was the control, whereas the second, third, and fourth were treated with 60 nM, 200 nM, and 2 μM ivabradine, respectively. We assessed five different contraction parameters before and after a 15 min treatment and calculated their relative changes, which were then compared to the control group. Results Ivabradine has affected the force of contraction significantly in vitro (p=0.009). However, force of contraction decreased in both the control group (93.5 ± 4.7%) and the second group (94.1 ± 4.5%, p=0.8) and force of contraction remained unchanged in the third group (101.0 ± 4.1%, p=0.24) and increased significantly in the fourth group (108.9 ± 11.6%, p=0.008). There was no change in other contraction parameters, such as passive tension force (97.1 ± 5.1%, p=0.368), duration of contraction (99.1 ± 4.3%, p=0.816), time to peak (96.6 ± 3.0%, p=0.536), and time to relaxation (101.2 ± 7.0%, p=0.564). Conclusions Ivabradine did not interfere with the contractile behaviour of human atrial tissue when it was used in therapeutic dosages in vitro. However, it increased the contractility slightly, when it was used in supratherapeutic dosage.
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25
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Niehoff J, Matzkies M, Nguemo F, Hescheler J, Reppel M. The Effect of Antiarrhythmic Drugs on the Beat Rate Variability of Human Embryonic and Human Induced Pluripotent Stem Cell Derived Cardiomyocytes. Sci Rep 2019; 9:14106. [PMID: 31575920 PMCID: PMC6773847 DOI: 10.1038/s41598-019-50557-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Accepted: 09/06/2019] [Indexed: 01/08/2023] Open
Abstract
Embryonic stem cell (ESC) derived tissue is a promising tool to be used in different clinical, preclinical and also scientific settings, for example as in vivo biological pacemaker, preclinical drug safety screening tool or ultimately as part of a cell replacement therapy. However, before ESC derived tissue can be used routinely for these purposes in humans, further studies are needed. In this context, the aims of the present study were to examine the effect of antiarrhythmic drugs on human ESC (hESC) und human induced pluripotent stem cell (hiPSC) derived cardiomyocytes by analyzing the beat rate variability (BRV), which can be considered as the in vitro equivalent of the heart rate variability (HRV) in vivo. Short-term recordings of extracellular field potentials of spontaneously beating cardiomyocytes derived from hESCs and hiPSCs were made using Microelectrode Arrays (MEA). The effect of Flecainide, Ivabradine and Metoprolol was tested. The offline analysis of the BRV was mainly focused on time domain methods. Additionally a non-linear analysis method was used. The evaluation of the Poincaré-Plots of the measurements without pharmacological intervention revealed that the vast majority of the scatter plots have a similar, ellipsoid shape. Flecainide and Ivabradine influenced BRV parameters significantly, whereas Metoprolol did not alter the BRV markedly. We detected remarkable similarities between the BRV of hESC and hiPSC derived cardiomyocytes in vitro and the HRV in vivo. The effect of antiarrhythmic drugs on spontaneously beating cardiomyocytes derived from hESC and hiPSC was generally consistent with clinical experiences and also with our previous study based on murine ESC derived cardiomyocytes. In conclusion, our study points out the great potential of hESC and hiPSC derived tissue to be used routinely for many different applications in medicine and science.
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Affiliation(s)
- Julius Niehoff
- Department of Diagnostic and Interventional Radiology, University Hospital of Cologne, Cologne, Germany. .,Institute for Neurophysiology, University of Cologne, Cologne, Germany.
| | - Matthias Matzkies
- Institute for Neurophysiology, University of Cologne, Cologne, Germany
| | - Filomain Nguemo
- Institute for Neurophysiology, University of Cologne, Cologne, Germany
| | - Jürgen Hescheler
- Institute for Neurophysiology, University of Cologne, Cologne, Germany
| | - Michael Reppel
- Institute for Neurophysiology, University of Cologne, Cologne, Germany
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26
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Pei H, Miao W, Xie WZ, Wang W, Zhao D, Su GH, Zhao Z. Ivabradine Improves Cardiac Function and Increases Exercise Capacity in Patients with Chronic Heart Failure. Int Heart J 2019; 60:899-909. [PMID: 31308326 DOI: 10.1536/ihj.18-559] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
To systematically review and conduct a meta-analysis of the ivabradine-induced improvement in cardiopulmonary function, exercise capacity, and primary composite endpoints in patients with chronic heart failure (CHF).This study was a systematic review and meta-analysis.Databases, including PubMed, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), and Clinical Trials and European Union Clinical Trials, were searched for randomized placebo-controlled trials. The efficacy and safety of ivabradine treatment in patients with CHF were assessed and compared to those of the standard anti-heart failure treatment. Review Manager 5.3 software was used to analyze the relative risk (RR) for dichotomous data and the mean difference (MD) for continuous data.In total, 22 studies with 24,562 patients were included. Cardiopulmonary function analysis showed that treatment with added ivabradine reduced the heart rate (MD = -17.30, 95% confidence interval (CI): 19.52--15.08, P < 0.00001), significantly increased the left ventricular ejection fraction (LVEF) (MD = 3.90, 95% CI: 0.40-7.40, P < 0.0001), and led to a better New York Heart Association (NYHA) classification. Ivabradine significantly reduced the minute ventilation/carbon dioxide production (VE/VCO2) (MD = -2.68, 95% CI: -4.81--0.55, P = 0.01) and improved the peak VO2 (MD = 2.80, 95% CI: 1.05-4.55, P = 0.002) and the exercise capacity, including the exercise duration with a submaximal load (MD = 7.82, 95% CI: -2.57--18.21, P < 0.00001) and the 6-minute walk distance. The RR of cardiovascular death or worsening heart failure was significantly decreased (RR = 0.93, 95% CI: 0.87--0.98, P = 0.01) in the patients treated with ivabradine. Additionally, the RRs of heart failure and hospitalization also decreased (RR = 0.91, 95% CI: 0.85--0.97, P = 0.006; RR = 0.86, 95% CI: 0.79--0.93, P = 0.0002). Safety analysis showed no significant difference in the RR of severe adverse events between the ivabradine group and the standard anti-heart failure treatment group (P = 0.40). However, ivabradine significantly increased the RR of visual symptoms in CHF patients (RR = 3.82, 95% CI: 1.80--8.13, P = 0.0005).Existing evidence showed that adding ivabradine treatment significantly improved the cardiopulmonary function and increased the exercise capacity of patients with CHF. Adding ivabradine to the standard anti-heart failure treatment reduced the mortality and hospitalization risk and improved the quality of life. Finally, ivabradine significantly increased the RR of visual symptoms in CHF patients.This is the first systematic review and meta-analysis to focus on the efficacy of ivabradine, which improved the cardiac function and increased the exercise capacity in patients with chronic heart failure (CHF). Therefore, this study will help evaluate the quality of life after adding ivabradine to the treatment of patients with CHF, even though there are differences in the standard for resting heart rate, left ventricular ejection fraction (LVEF), and New York Heart Association (NYHA) class in the included studies. This hybrid effect might be smaller when analyzed separately but might have a higher heterogeneity when analyzed in multiple studies.
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Affiliation(s)
- Hui Pei
- Department of Cardiology, Jinan Central Hospital Affiliated with Shandong University.,Ti'an City Central Hospital
| | - Wei Miao
- Department of Cardiology, Jinan Central Hospital Affiliated with Shandong University
| | - Wen-Zhi Xie
- Department of Cardiology, Jinan Central Hospital Affiliated with Shandong University
| | - Wei Wang
- Department of Cardiology, Shandong Provincial Chest Hospital
| | - Di Zhao
- Department of Cardiology, Affiliated Hospital of Shandong Academy of Medical Sciences
| | - Guo-Hai Su
- Department of Cardiology, Jinan Central Hospital Affiliated with Shandong University
| | - Zhuo Zhao
- Department of Cardiology, Jinan Central Hospital Affiliated with Shandong University
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27
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Chen SJ, Xu Y, Liang YM, Cao Y, Lv JY, Pang JX, Zhou PZ. Identification and characterization of a series of novel HCN channel inhibitors. Acta Pharmacol Sin 2019; 40:746-754. [PMID: 30315249 DOI: 10.1038/s41401-018-0162-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Accepted: 08/13/2018] [Indexed: 11/09/2022] Open
Abstract
Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels play a critical role in controlling pacemaker activity in both heart and nervous system. Developing HCN channel inhibitors has been proposed to be an important strategy for the treatment of pain, heart failure, arrhythmias, and epilepsy. One HCN channel inhibitor, ivabradine, has been clinically approved for the treatment of angina pectoris and heart failure. In this study, we designed and synthesized eight alkanol amine derivatives, and assessed their effects on HCN channels expressed in COS7 cells using a whole-cell patch clamp method. Among them, compound 4e displayed the most potent inhibitory activity with an IC50 of 2.9 ± 1.2 µM at - 120 mV on HCN2 channel expressed in COS7 cells. Further analysis revealed that application of compound 4e (10 μM) caused a slowing of activation and a hyperpolarizing shift (ΔV1/2 = - 30.2 ± 2.9 mV, n = 5) in the voltage dependence of HCN2 channel activation. The inhibitory effect of compound 4e on HCN1 and HCN4 channel expressed in COS7 cells was less potent with IC50 of 17.2 ± 1.3 and 7.3 ± 1.2 μM, respectively. Besides, we showed that application of compound 4e (10 μM) inhibited Ih and action potential firing in acutely dissociated mouse small dorsal root ganglion neurons. Our study provides a new strategy for the design and development of potent HCN channel inhibitors.
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28
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Katsi V, Skalis G, Kallistratos MS, Tsioufis K, Makris T, Manolis AJ, Tousoulis D. Ivabradine and metoprolol in fixed dose combination: When, why and how to use it. Pharmacol Res 2019; 146:104279. [PMID: 31108185 DOI: 10.1016/j.phrs.2019.104279] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 04/01/2019] [Accepted: 05/16/2019] [Indexed: 11/30/2022]
Abstract
Heart rate is an important factor in coronary artery disease and its manifestations, and as such has been considered as a possible target for therapy. Although in epidemiological, and in less degree, in clinical studies derived indications of a possible pathogenetic role of heart rate in major cardiac diseases, clinical trials did not provided any strong evidence. However, even as a simple risk marker, remains important in the treatment of coronary artery disease and heart failure. Beta-blockers are the drugs most frequently used for heart rate control. However, recent studies constantly find insufficient effectiveness of beta-blockers in heart rate control and go further to question their efficacy on outcomes, making clear the need for an additional therapy. Ivabradine, a pure heart rate inhibitor, added to classic beta-blocker treatment represent the new therapeutic option in stable coronary disease and heart failure.
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Affiliation(s)
- V Katsi
- Cardiology Department, Hippokration Hospital, Athens, Greece
| | - G Skalis
- Department of Cardiology, Helena Venizelou Hospital, Athens, Greece
| | - M S Kallistratos
- Department of Cardiology, Asklepeion General Hospital, Athens, Greece.
| | - K Tsioufis
- Cardiology Department, Hippokration Hospital, Athens, Greece
| | - T Makris
- Department of Cardiology, Helena Venizelou Hospital, Athens, Greece
| | - A J Manolis
- Department of Cardiology, Asklepeion General Hospital, Athens, Greece
| | - D Tousoulis
- Department of Cardiology, Asklepeion General Hospital, Athens, Greece
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29
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Ivabradine versus propranolol given orally in microlaryngoscopic surgeries in attenuating stress response: A comparative prospective double blind randomized study. EGYPTIAN JOURNAL OF ANAESTHESIA 2019. [DOI: 10.1016/j.egja.2016.08.020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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30
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Positive Feedback Mechanisms among Local Ca Releases, NCX, and I CaL Ignite Pacemaker Action Potentials. Biophys J 2019. [PMID: 29539403 DOI: 10.1016/j.bpj.2017.12.043] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Recent data suggest that cardiac pacemaker cell function is determined by numerous time-, voltage-, and Ca-dependent interactions of cell membrane electrogenic proteins (M-clock) and intracellular Ca cycling proteins (Ca-clock), forming a coupled-clock system. Many aspects of the coupled-clock system, however, remain underexplored. The key players of the system are Ca release channels (ryanodine receptors), generating local Ca releases (LCRs) from sarcoplasmic reticulum, electrogenic Na/Ca exchanger (NCX) current, and L-type Ca current (ICaL). We combined numerical model simulations with experimental simultaneous recordings of action potentials (APs) and Ca to gain further insight into the complex interactions within the system. Our simulations revealed a positive feedback mechanism, dubbed AP ignition, which accelerates the diastolic depolarization (DD) to reach AP threshold. The ignition phase begins when LCRs begin to occur and the magnitude of inward NCX current begins to increase. The NCX current, together with funny current and T-type Ca current accelerates DD, bringing the membrane potential to ICaL activation threshold. During the ignition phase, ICaL-mediated Ca influx generates more LCRs via Ca-induced Ca release that further activates inward NCX current, creating a positive feedback. Simultaneous recordings of membrane potential and confocal Ca images support the model prediction of the positive feedback among LCRs and ICaL, as diastolic LCRs begin to occur below and continue within the voltage range of ICaL activation. The ignition phase onset (identified within the fine DD structure) begins when DD starts to notably accelerate (∼0.15 V/s) above the recording noise. Moreover, the timing of the ignition onset closely predicted the duration of each AP cycle in the basal state, in the presence of autonomic receptor stimulation, and in response to specific inhibition of either the M-clock or Ca-clock, thus indicating general importance of the new coupling mechanism for regulation of the pacemaker cell cycle duration, and ultimately the heart rate.
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31
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Tanguay J, Callahan KM, D'Avanzo N. Characterization of drug binding within the HCN1 channel pore. Sci Rep 2019; 9:465. [PMID: 30679654 PMCID: PMC6345760 DOI: 10.1038/s41598-018-37116-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Accepted: 11/29/2018] [Indexed: 11/09/2022] Open
Abstract
Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels mediate rhythmic electrical activity of cardiac pacemaker cells, and in neurons play important roles in setting resting membrane potentials, dendritic integration, neuronal pacemaking, and establishing action potential threshold. Block of HCN channels slows the heart rate and is currently used to treat angina. However, HCN block also provides a promising approach to the treatment of neuronal disorders including epilepsy and neuropathic pain. While several molecules that block HCN channels have been identified, including clonidine and its derivative alinidine, lidocaine, mepivacaine, bupivacaine, ZD7288, ivabradine, zatebradine, and cilobradine, their low affinity and lack of specificity prevents wide-spread use. Different studies suggest that the binding sites of these inhibitors are located in the inner vestibule of HCN channels, but the molecular details of their binding remain unknown. We used computational docking experiments to assess the binding sites and mode of binding of these inhibitors against the recently solved atomic structure of human HCN1 channels, and a homology model of the open pore derived from a closely related CNG channel. We identify a possible hydrophobic groove in the pore cavity that plays an important role in conformationally restricting the location and orientation of drugs bound to the inner vestibule. Our results also help explain the molecular basis of the low-affinity binding of these inhibitors, paving the way for the development of higher affinity molecules.
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Affiliation(s)
- Jérémie Tanguay
- Department of Physics, Université de Montréal, Montréal, Canada
| | - Karen M Callahan
- Department of Pharmacology and Physiology, Université de Montréal, Montréal, Canada
| | - Nazzareno D'Avanzo
- Department of Pharmacology and Physiology, Université de Montréal, Montréal, Canada.
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32
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Ide T, Ohtani K, Higo T, Tanaka M, Kawasaki Y, Tsutsui H. Ivabradine for the Treatment of Cardiovascular Diseases. Circ J 2018; 83:252-260. [PMID: 30606942 DOI: 10.1253/circj.cj-18-1184] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Higher heart rate (HR) is independently related to worse outcomes in various cardiac diseases, including hypertension, coronary artery disease, and heart failure (HF). HR is determined by the pacemaker activity of cells within the sinoatrial node. The hyperpolarization-activated cyclic nucleotide-gated (HCN) 4 channel, one of 4 HCN isoforms, generates the If current and plays an important role in the regulation of pacemaker activity in the sinoatrial node. Ivabradine is a novel and only available HCN inhibitor, which can reduce HR and has been approved for stable angina and chronic HF in many countries other than Japan. In this review, we summarize the current knowledge of the HCN4 channel and ivabradine, including the function of HCN4 in cardiac pacemaking, the mechanism of action of If inhibition by ivabradine, and the pharmacological and clinical effects of ivabradine in cardiac diseases as HF, coronary artery disease, and atrial fibrillation.
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Affiliation(s)
- Tomomi Ide
- Department of Experimental and Clinical Cardiovascular Medicine, Graduate School of Medical Sciences, Kyushu University
| | - Kisho Ohtani
- Department of Experimental and Clinical Cardiovascular Medicine, Graduate School of Medical Sciences, Kyushu University
| | - Taiki Higo
- Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kyushu University
| | | | | | - Hiroyuki Tsutsui
- Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kyushu University
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Canine and human sinoatrial node: differences and similarities in the structure, function, molecular profiles, and arrhythmia. J Vet Cardiol 2018; 22:2-19. [PMID: 30559056 DOI: 10.1016/j.jvc.2018.10.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 10/02/2018] [Accepted: 10/02/2018] [Indexed: 12/17/2022]
Abstract
The sinoatrial node (SAN) is the primary pacemaker in canine and human hearts. The SAN in both species has a unique three-dimensional heterogeneous structure characterized by small pacemaker myocytes enmeshed within fibrotic strands, which partially insulate the cells from aberrant atrial activation. The SAN pacemaker tissue expresses a unique signature of proteins and receptors that mediate SAN automaticity, ion channel currents, and cell-to-cell communication, which are predominantly similar in both species. Recent intramural optical mapping, integrated with structural and molecular studies, has revealed the existence of up to five specialized SAN conduction pathways that preferentially conduct electrical activation to atrial tissues. The intrinsic heart rate, intranodal leading pacemaker shifts, and changes in conduction in response to physiological and pathophysiological stimuli are similar. Structural and/or functional impairments due to cardiac diseases including heart failure cause SAN dysfunctions (SNDs) in both species. These dysfunctions are usually manifested as severe bradycardia, tachy-brady arrhythmias, and conduction abnormalities including exit block and SAN reentry, which could lead to atrial tachycardia and fibrillation, cardiac arrest, and heart failure. Pharmaceutical drugs and implantable pacemakers are only partially successful in managing SNDs, emphasizing a critical need to develop targeted mechanism-based therapies to treat SNDs. Because several structural and functional characteristics are similar between the canine and human SAN, research in these species may be mutually beneficial for developing novel treatment approaches. This review describes structural, functional, and molecular similarities and differences between the canine and human SAN, with special emphasis on arrhythmias and unique causal mechanisms of SND in diseased hearts.
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Chow SL, Page RL, Depre C. Role of ivabradine and heart rate lowering in chronic heart failure: guideline update. Expert Rev Cardiovasc Ther 2018; 16:515-526. [PMID: 29902387 DOI: 10.1080/14779072.2018.1489235] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
INTRODUCTION This review summarizes the current management of heart failure (HF) in patients with reduced ejection fraction and the potential role of heart rate lowering agents in select populations, as recommended in the updated guidelines. Areas covered: PubMed was searched for studies that evaluated the role of heart rate lowering or ivabradine in HF management. Expert commentary: Targeting heart rate may offer benefit when added to renin-angiotensin aldosterone antagonists, and beta-blockers. Ivabradine is a heart rate lowering agent that acts on the funny current (If) in the sinoatrial node, thereby reducing heart rate without directly affecting cardiac contraction and relaxation. Clinical data from a phase III trial demonstrated that ivabradine reduced the composite end point of cardiovascular death or hospital admission for worsening systolic HF, while maintaining an acceptable safety profile in patients receiving standard of care therapy. These data, in addition to more recently published guidelines, suggest ivabradine as a promising new treatment option for lowering heart rate after optimizing standard therapy in select patients with chronic HF.
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Affiliation(s)
- Sheryl L Chow
- a Department of Pharmacy , Western University of Health Sciences , Pomona , CA , USA
| | - Robert L Page
- b Department of Clinical Pharmacy , University of Colorado , Denver , CO , USA
| | - Christophe Depre
- c Clinical Research Medical Director , Amgen Inc ., Thousand Oaks , CA , USA
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Kaski JC, Gloekler S, Ferrari R, Fox K, Lévy BI, Komajda M, Vardas P, Camici PG. Role of ivabradine in management of stable angina in patients with different clinical profiles. Open Heart 2018; 5:e000725. [PMID: 29632676 PMCID: PMC5888443 DOI: 10.1136/openhrt-2017-000725] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Revised: 12/29/2017] [Accepted: 02/14/2018] [Indexed: 12/12/2022] Open
Abstract
In chronic stable angina, elevated heart rate contributes to the development of symptoms and signs of myocardial ischaemia by increasing myocardial oxygen demand and reducing diastolic perfusion time. Accordingly, heart rate reduction is a well-known strategy for improving both symptoms of myocardial ischaemia and quality of life (QOL). The heart rate-reducing agent ivabradine, a direct and selective inhibitor of the If current, decreases myocardial oxygen consumption while increasing diastolic time, without affecting myocardial contractility or coronary vasomotor tone. Ivabradine is indicated for treatment of stable angina and chronic heart failure (HF). This review examines available evidence regarding the efficacy and safety of ivabradine in stable angina, when used as monotherapy or in combination with beta-blockers, in particular angina subgroups and in patients with stable angina with left ventricular systolic dysfunction (LVSD) or HF. Trials involving more than 45 000 patients receiving treatment with ivabradine have shown that this agent has antianginal and anti-ischaemic effects, regardless of age, sex, severity of angina, revascularisation status or comorbidities. This heart rate-lowering agent might also improve prognosis, reduce hospitalisation rates and improve QOL in angina patients with chronic HF and LVSD.
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Affiliation(s)
- Juan Carlos Kaski
- Molecular and Clinical Sciences Research Institute, St George's, University of London, London, UK
| | - Steffen Gloekler
- Department of Cardiology, Schwarzwald-Baar Klinikum, Villingen-Schwenningen, Germany.,Cardiology, Cardiovascular Department, Bern University Hospital, Bern, Switzerland
| | - Roberto Ferrari
- Centro Cardiologico Universitario di Ferrara, University of Ferrara, Ferrara, Italy.,Maria Cecilia Hospital, GVM Care & Research, Cotignola, Italy
| | - Kim Fox
- National Heart and Lung Institute, Imperial College, Institute of Cardiovascular Medicine and Science, Royal Brompton Hospital, London, UK
| | - Bernard I Lévy
- PARCC, INSERM U970, Vessels and Blood Institute, Hôpital Lariboisière, Paris, France
| | - Michel Komajda
- Department of Cardiology, Université Pierre et Marie Curie Paris VI, La Pitié-Salpêtrière Hospital, Paris, France
| | - Panos Vardas
- Cardiology Department, University Hospital of Heraklion, Heraklion, Greece
| | - Paolo G Camici
- Cardiology Department, Vita Salute University and San Raffaele Hospital, Milan, Italy
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Role of the Funny Current Inhibitor Ivabradine in Cardiac Pharmacotherapy: A Systematic Review. Am J Ther 2018; 25:e247-e266. [DOI: 10.1097/mjt.0000000000000388] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Sartiani L, Mannaioni G, Masi A, Novella Romanelli M, Cerbai E. The Hyperpolarization-Activated Cyclic Nucleotide-Gated Channels: from Biophysics to Pharmacology of a Unique Family of Ion Channels. Pharmacol Rev 2017; 69:354-395. [PMID: 28878030 DOI: 10.1124/pr.117.014035] [Citation(s) in RCA: 82] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 07/07/2017] [Indexed: 12/22/2022] Open
Abstract
Hyperpolarization-activated, cyclic nucleotide-gated (HCN) channels are important members of the voltage-gated pore loop channels family. They show unique features: they open at hyperpolarizing potential, carry a mixed Na/K current, and are regulated by cyclic nucleotides. Four different isoforms have been cloned (HCN1-4) that can assemble to form homo- or heterotetramers, characterized by different biophysical properties. These proteins are widely distributed throughout the body and involved in different physiologic processes, the most important being the generation of spontaneous electrical activity in the heart and the regulation of synaptic transmission in the brain. Their role in heart rate, neuronal pacemaking, dendritic integration, learning and memory, and visual and pain perceptions has been extensively studied; these channels have been found also in some peripheral tissues, where their functions still need to be fully elucidated. Genetic defects and altered expression of HCN channels are linked to several pathologies, which makes these proteins attractive targets for translational research; at the moment only one drug (ivabradine), which specifically blocks the hyperpolarization-activated current, is clinically available. This review discusses current knowledge about HCN channels, starting from their biophysical properties, origin, and developmental features, to (patho)physiologic role in different tissues and pharmacological modulation, ending with their present and future relevance as drug targets.
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Affiliation(s)
- Laura Sartiani
- Department of Neurosciences, Psychology, Drug Research, and Child Health, University of Florence, Firenze, Italy
| | - Guido Mannaioni
- Department of Neurosciences, Psychology, Drug Research, and Child Health, University of Florence, Firenze, Italy
| | - Alessio Masi
- Department of Neurosciences, Psychology, Drug Research, and Child Health, University of Florence, Firenze, Italy
| | - Maria Novella Romanelli
- Department of Neurosciences, Psychology, Drug Research, and Child Health, University of Florence, Firenze, Italy
| | - Elisabetta Cerbai
- Department of Neurosciences, Psychology, Drug Research, and Child Health, University of Florence, Firenze, Italy
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Priti K, Ranwa BL, Gokhroo RK, Kishore K, Bisht DS, Gupta S. Ivabradine vs metoprolol in patients with acute inferior wall myocardial infarction-“Expanding arena for ivabradine”. Cardiovasc Ther 2017; 35. [DOI: 10.1111/1755-5922.12266] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 03/06/2017] [Accepted: 04/12/2017] [Indexed: 11/28/2022] Open
Affiliation(s)
- Kumari Priti
- Department of Cardiology; JLN Medical College; Ajmer Rajasthan India
| | - Bhanwar L. Ranwa
- Department of Cardiology; JLN Medical College; Ajmer Rajasthan India
| | | | - Kamal Kishore
- Department of Cardiology; JLN Medical College; Ajmer Rajasthan India
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Abstract
Objective To investigate the effect of a heart rate (HR) lowering agent (Ivabradine) on features of atherosclerotic plaque vulnerability with magnetic resonance imaging (MRI), ultrasound imaging, and histology. Approach and results Atherosclerosis was induced in the abdominal aorta of 19 rabbits. Nine rabbits were treated with Ivabradine (17 mg/kg/day) during the entire study period. At week 14, imaging was performed. Plaque size was quantified on contrast-enhanced T1-weighted MR images. Microvascular flow, density, and permeability was studied with dynamic contrast-enhanced MRI. Plaque biomechanics was studied by measuring the aortic distension with ultrasound. After, animals were sacrificed and histology was performed. HR was reduced by 16% (p = 0.026) in Ivabradine-treated animals. No differences in absolute and relative vessel wall beat-to-beat distension were found, but due to the reduction in HR, the frequency of the biomechanical load on the plaque was reduced. Plaque size (MR and histology) was similar between groups. Although microvessel density (histology) was similar between groups, AUC and Ktrans, indicative for plaque microvasculature flow, density, and permeability, were decreased by 24% (p = 0.029) and 32% (p = 0.037), respectively. Macrophage content (relative RAM11 positive area) was reduced by 44% (p<0.001) on histology in Ivabradine-treated animals. Conclusions HR lowering treatment with Ivabradine in an atherosclerotic rabbit model is associated with a reduction in vulnerable plaque features. The current study suggests that HR reduction may be beneficial for inducing or maintaining a more stable plaque phenotype.
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Slater RE, Strom JG, Granzier H. Effect of exercise on passive myocardial stiffness in mice with diastolic dysfunction. J Mol Cell Cardiol 2017; 108:24-33. [PMID: 28476659 DOI: 10.1016/j.yjmcc.2017.04.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Revised: 04/24/2017] [Accepted: 04/27/2017] [Indexed: 12/20/2022]
Abstract
Heart failure with preserved ejection fraction (HFpEF) is a complex syndrome, characterized by increased diastolic stiffness and a preserved ejection fraction, with no effective treatment options. Here we studied the therapeutic potential of exercise for improving diastolic function in a mouse model with HFpEF-like symptoms, the TtnΔIAjxn mouse model. TtnΔIAjxn mice have increased diastolic stiffness and reduced exercise tolerance, mimicking aspects of HFpEF observed in patients. We investigated the effect of free-wheel running exercise on diastolic function. Mechanical studies on cardiac muscle strips from the LV free wall revealed that both TtnΔIAjxn and wildtype (WT) exercised mice had a reduction in passive stiffness, relative to sedentary controls. In both genotypes, this reduction is due to an increase in the compliance of titin whereas ECM-based stiffness was unaffected. Phosphorylation of titin's PEVK and N2B spring elements were assayed with phospho-site specific antibodies. Exercised mice had decreased PEVK phosphorylation and increased N2B phosphorylation both of which are predicted to contribute to the increased compliance of titin. Since exercise lowers the heart rate we examined whether reduction in heart rate per se can improve passive stiffness by administering the heart-rate-lowering drug ivabradine. Ivabradine lowered heart rate in our study but it did not affect passive tension, in neither WT nor TtnΔIAjxn mice. We conclude that exercise is beneficial for decreasing passive stiffness and that it involves beneficial alterations in titin phosphorylation.
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Affiliation(s)
- Rebecca E Slater
- Department of Cellular and Molecular Medicine, University of Arizona, Tucson, AZ 85721, United States; Sarver Molecular Cardiovascular Research Program, University of Arizona, Tucson, AZ 85721, United States
| | - Joshua G Strom
- Department of Cellular and Molecular Medicine, University of Arizona, Tucson, AZ 85721, United States; Sarver Molecular Cardiovascular Research Program, University of Arizona, Tucson, AZ 85721, United States
| | - Henk Granzier
- Department of Cellular and Molecular Medicine, University of Arizona, Tucson, AZ 85721, United States; Sarver Molecular Cardiovascular Research Program, University of Arizona, Tucson, AZ 85721, United States.
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Putrenko I, Yip R, Schwarz SKW, Accili EA. Cation and voltage dependence of lidocaine inhibition of the hyperpolarization-activated cyclic nucleotide-gated HCN1 channel. Sci Rep 2017; 7:1281. [PMID: 28455536 PMCID: PMC5430837 DOI: 10.1038/s41598-017-01253-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Accepted: 03/28/2017] [Indexed: 12/17/2022] Open
Abstract
Lidocaine is known to inhibit the hyperpolarization-activated mixed cation current (Ih) in cardiac myocytes and neurons, as well in cells transfected with cloned Hyperpolarization-activated Cyclic Nucleotide-gated (HCN) channels. However, the molecular mechanism of Ih inhibition by this drug has been limitedly explored. Here, we show that inhibition of Ih by lidocaine, recorded from Chinese hamster ovary (CHO) cells expressing the HCN1 channel, reached a steady state within one minute and was reversible. Lidocaine inhibition of Ih was greater at less negative voltages and smaller current amplitudes whereas the voltage-dependence of Ih activation was unchanged. Lidocaine inhibition of Ih measured at −130 mV (a voltage at which Ih is fully activated) was reduced, and Ih amplitude was increased, when the concentration of extracellular potassium was raised to 60 mM from 5.4 mM. By contrast, neither Ih inhibition by the drug nor Ih amplitude at +30 mV (following a test voltage-pulse to −130 mV) were affected by this rise in extracellular potassium. Together, these data indicate that lidocaine inhibition of Ih involves a mechanism which is antagonized by hyperpolarizing voltages and current flow.
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Affiliation(s)
- Igor Putrenko
- Department of Cellular and Physiological Sciences, The University of British Columbia, Vancouver, British Columbia, Canada.,Department of Anesthesiology, Pharmacology & Therapeutics, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Raymond Yip
- Department of Cellular and Physiological Sciences, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Stephan K W Schwarz
- Department of Anesthesiology, Pharmacology & Therapeutics, The University of British Columbia, Vancouver, British Columbia, Canada.,Department of Anesthesia, St. Paul's Hospital/Providence Health Care, Vancouver, British Columbia, Canada
| | - Eric A Accili
- Department of Cellular and Physiological Sciences, The University of British Columbia, Vancouver, British Columbia, Canada.
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Zhang Z, Huang TQ, Nepliouev I, Zhang H, Barnett AS, Rosenberg PB, Ou SHI, Stiber JA. Crizotinib Inhibits Hyperpolarization-activated Cyclic Nucleotide-Gated Channel 4 Activity. CARDIO-ONCOLOGY 2017; 3. [PMID: 28217366 PMCID: PMC5310672 DOI: 10.1186/s40959-017-0020-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
BACKGROUND Sinus bradycardia is frequently observed in patients treated with crizotinib, a receptor tyrosine kinase inhibitor used for the treatment of anaplastic lymphoma kinase (ALK)-rearranged non-small cell lung cancer (NSCLC). We investigated whether crizotinib could influence heart rate (HR) through direct cardiac effects. METHODS The direct effect of crizotinib on HR was studied using ECG analysis of Langendorff-perfused mouse hearts. The whole-cell patch clamp technique was used to measure the effects of crizotinib on the hyperpolarization-activated funny current, If, in mouse sinoatrial node cells (SANCs) and hyperpolarization-activated cyclic nucleotide-gated channel 4 (HCN4) activity in HEK-293 cells stably expressing human HCN4. RESULTS Crizotinib resulted in a dose-dependent reduction in HR in isolated intact mouse hearts with a half maximal inhibitory concentration (IC50) of 1.7 ± 0.4 μmol/L. Because ECG analysis revealed that crizotinib (0-5 μmol/L) resulted in significant reductions in HR in isolated mouse hearts without changes in PR, QRS, or QT intervals, we performed whole-cell patch clamp recordings of SANCs which showed that crizotinib inhibited If which regulates cardiac pacemaker activity. Crizotinib resulted in diminished current density of HCN4, the major molecular determinant of If, with an IC50 of 1.4 ± 0.3 μmol/L. Crizotinib also slowed HCN4 activation and shifted the activation curve to the left towards more hyperpolarized potentials. CONCLUSIONS Our results suggest that crizotinib's effects on HCN4 channels play a significant role in mediating its observed effects on HR.
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Affiliation(s)
- Zhushan Zhang
- Department of Medicine, Duke University Medical Center, Durham, NC USA 27710
| | - Tai-Qin Huang
- Department of Medicine, Duke University Medical Center, Durham, NC USA 27710
| | - Igor Nepliouev
- Department of Medicine, Duke University Medical Center, Durham, NC USA 27710
| | - Hengtao Zhang
- Department of Medicine, Duke University Medical Center, Durham, NC USA 27710
| | - Adam S Barnett
- Department of Medicine, Duke University Medical Center, Durham, NC USA 27710
| | - Paul B Rosenberg
- Department of Medicine, Duke University Medical Center, Durham, NC USA 27710
| | - Sai-Hong I Ou
- Department of Medicine, University of California Irvine School of Medicine, Orange, CA 92868
| | - Jonathan A Stiber
- Department of Medicine, Duke University Medical Center, Durham, NC USA 27710
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Krzesiak A, Delpech N, Sebille S, Cognard C, Chatelier A. Structural, Contractile and Electrophysiological Adaptations of Cardiomyocytes to Chronic Exercise. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 999:75-90. [PMID: 29022258 DOI: 10.1007/978-981-10-4307-9_5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Cardiac beneficial effects of chronic exercise is well admitted. These effects mainly studied at the organ and organism integrated levels find their origin in cardiomyocyte adaptation. This chapter try to highlight the main trends of the data related to the different parameters subject to such adaptations. This is addressed through cardiomyocytes size and structure, calcium and contractile properties, and finally electrophysiological alterations induced by training as they transpire from the literature. Despite the clarifications needed to decipher healthy cardiomyocyte remodeling, this overview clearly show that cardiac cell plasticity ensure the cardiac adaptation to exercise training and offers an interesting mean of action to counteract physiological disturbances induced by cardiac pathologies.
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Affiliation(s)
- A Krzesiak
- Equipe Transferts Ioniques et Rythmicité Cardiaque (TIRC), Lab. Signalisation et Transports Ioniques Membranaires (STIM), ERL CNRS/Université de Poitiers n°7368, Faculté des Sciences Fondamentales et Appliquées, Pôle Biologie Santé Bât B36/B37, 1 rue Georges Bonnet TSA 51106, 86073, Poitiers Cedex 9, France.,Laboratoire Mobilité, Vieillissement & Exercice (MOVE) - EA 6314, Faculté des Sciences du Sport Bât C6, 8, allée Jean Monnet, TSA 31113, 86073, Poitiers Cedex 9, France
| | - N Delpech
- Laboratoire Mobilité, Vieillissement & Exercice (MOVE) - EA 6314, Faculté des Sciences du Sport Bât C6, 8, allée Jean Monnet, TSA 31113, 86073, Poitiers Cedex 9, France
| | - S Sebille
- Equipe Transferts Ioniques et Rythmicité Cardiaque (TIRC), Lab. Signalisation et Transports Ioniques Membranaires (STIM), ERL CNRS/Université de Poitiers n°7368, Faculté des Sciences Fondamentales et Appliquées, Pôle Biologie Santé Bât B36/B37, 1 rue Georges Bonnet TSA 51106, 86073, Poitiers Cedex 9, France
| | - C Cognard
- Equipe Transferts Ioniques et Rythmicité Cardiaque (TIRC), Lab. Signalisation et Transports Ioniques Membranaires (STIM), ERL CNRS/Université de Poitiers n°7368, Faculté des Sciences Fondamentales et Appliquées, Pôle Biologie Santé Bât B36/B37, 1 rue Georges Bonnet TSA 51106, 86073, Poitiers Cedex 9, France
| | - A Chatelier
- Equipe Transferts Ioniques et Rythmicité Cardiaque (TIRC), Lab. Signalisation et Transports Ioniques Membranaires (STIM), ERL CNRS/Université de Poitiers n°7368, Faculté des Sciences Fondamentales et Appliquées, Pôle Biologie Santé Bât B36/B37, 1 rue Georges Bonnet TSA 51106, 86073, Poitiers Cedex 9, France.
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Huang X, Zhong N, Zhang H, Ma A, Yuan Z, Guo N. Reduced expression of HCN channels in the sinoatrial node of streptozotocin-induced diabetic rats. Can J Physiol Pharmacol 2016; 95:586-594. [PMID: 28177679 DOI: 10.1139/cjpp-2016-0418] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Diabetes mellitus (DM) is associated with an electrical remodeling of the heart, increasing the risk of arrhythmias. However, knowledge of electrical remodeling in the sinoatrial node (SAN) by DM is limited. We investigated the expression of HCN channel isoforms, HCN1-HCN4, in SAN from streptozotocin (STZ)-induced diabetic rats and the age-matched controls. We found that the STZ-induced diabetic rats have a lower intrinsic heart rate, a lengthened sinoatrial conduction time, and rate-corrected maximal sinoatrial node recovery time in vivo as well as a longer cycle length (CL) in vitro, as compared with the control. Optical mapping of the SAN demonstrated an inferior leading pacemaker site, reduced SAN conduction velocity and diastolic depolarization slope, and a longer action potential duration in the STZ-induced diabetic rats than in the control. The transcripts and proteins of HCN2 and HCN4 in diabetic SAN were reduced. Specific blockade of HCN channels by 3 μmol/L ivabradine significantly prolonged the CL of a Langendorff heart by 18% in the diabetic rats and 26% in the control. The reduced expression of HCN channel isoforms in the SAN of the STZ-induced diabetic rat may be an important contributor to the reduced SAN function in DM.
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Affiliation(s)
- Xin Huang
- a Department of Cardiology, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, P.R. China, 710061
| | - Nier Zhong
- b Department of Cardiology, Shaanxi Provincial People's Hospital, Xi'an, Shaanxi, P.R. China, 710068
| | - Hong Zhang
- c School of Electrical Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi, P.R. China, 710049
| | - Aiqun Ma
- a Department of Cardiology, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, P.R. China, 710061
| | - Zuyi Yuan
- a Department of Cardiology, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, P.R. China, 710061
| | - Ning Guo
- a Department of Cardiology, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, P.R. China, 710061
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Impact of Ivabradine on Inflammatory Markers in Chronic Heart Failure. J Immunol Res 2016; 2016:6949320. [PMID: 27822484 PMCID: PMC5086393 DOI: 10.1155/2016/6949320] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Revised: 08/28/2016] [Accepted: 09/20/2016] [Indexed: 01/25/2023] Open
Abstract
Background. Inflammation plays a crucial role in the progression of chronic heart failure (CHF). Ivabradine is known to reduce the morbidity and mortality of patients with CHF under certain conditions. Beyond the reduction of heart rate, only limited knowledge exists about potential anti-inflammatory effects of ivabradine that might contribute to its benefit in CHF. Thus, the present study aimed to investigate the effect of ivabradine on systemic inflammation. Methods. In the present study, 33 patients with CHF due to dilated, ischemic, and hypertensive cardiomyopathy were treated with ivabradine according to the guidelines of the European Society of Cardiology (ESC). A number of circulating dendritic cells as well as inflammatory mediators were investigated using FACS analysis and ELISA, respectively, before and during ivabradine therapy. Results. Treatment with ivabradine resulted in a significant improvement of CHF symptoms as well as an increase in left ventricular ejection fraction. Moreover, ivabradine treatment led to a significant reduction of TNF-alpha (TNF-α) serum levels and a reconstitution of circulating dendritic cells which are known to be reduced in patients with CHF. Conclusion. We show that treatment with ivabradine in patients with CHF resulted in an improvement of HF symptoms and ejection fraction as well as a normalization of inflammatory mediators.
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Silva FC, Paiva FA, Müller-Ribeiro FC, Caldeira HMA, Fontes MAP, de Menezes RCA, Casali KR, Fortes GH, Tobaldini E, Solbiati M, Montano N, Dias Da Silva VJ, Chianca DA. Chronic Treatment with Ivabradine Does Not Affect Cardiovascular Autonomic Control in Rats. Front Physiol 2016; 7:305. [PMID: 27507948 PMCID: PMC4960883 DOI: 10.3389/fphys.2016.00305] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Accepted: 07/06/2016] [Indexed: 12/05/2022] Open
Abstract
A low resting heart rate (HR) would be of great benefit in cardiovascular diseases. Ivabradine—a novel selective inhibitor of hyperpolarization-activated cyclic nucleotide gated (HCN) channels- has emerged as a promising HR lowering drug. Its effects on the autonomic HR control are little known. This study assessed the effects of chronic treatment with ivabradine on the modulatory, reflex and tonic cardiovascular autonomic control and on the renal sympathetic nerve activity (RSNA). Male Wistar rats were divided in 2 groups, receiving intraperitoneal injections of vehicle (VEH) or ivabradine (IVA) during 7 or 8 consecutive days. Rats were submitted to vessels cannulation to perform arterial blood pressure (AP) and HR recordings in freely moving rats. Time series of resting pulse interval and systolic AP were used to measure cardiovascular variability parameters. We also assessed the baroreflex, chemoreflex and the Bezold-Jarish reflex sensitivities. To better evaluate the effects of ivabradine on the autonomic control of the heart, we performed sympathetic and vagal autonomic blockade. As expected, ivabradine-treated rats showed a lower resting (VEH: 362 ± 16 bpm vs. IVA: 260 ± 14 bpm, p = 0.0005) and intrinsic HR (VEH: 369 ± 9 bpm vs. IVA: 326 ± 11 bpm, p = 0.0146). However, the chronic treatment with ivabradine did not change normalized HR spectral parameters LF (nu) (VEH: 24.2 ± 4.6 vs. IVA: 29.8 ± 6.4; p > 0.05); HF (nu) (VEH: 75.1 ± 3.7 vs. IVA: 69.2 ± 5.8; p > 0.05), any cardiovascular reflexes, neither the tonic autonomic control of the HR (tonic sympathovagal index; VEH: 0.91± 0.02 vs. IVA: 0.88 ± 0.03, p = 0.3494). We performed the AP, HR and RSNA recordings in urethane-anesthetized rats. The chronic treatment with ivabradine reduced the resting HR (VEH: 364 ± 12 bpm vs. IVA: 207 ± 11 bpm, p < 0.0001), without affecting RSNA (VEH: 117 ± 16 vs. IVA: 120 ± 9 spikes/s, p = 0.9100) and mean arterial pressure (VEH: 70 ± 4 vs. IVA: 77 ± 6 mmHg, p = 0.3293). Our results suggest that, in health rats, the long-term treatment with ivabradine directly reduces the HR without changing the RSNA modulation and the reflex and tonic autonomic control of the heart.
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Affiliation(s)
- Fernanda C Silva
- Laboratory of Cardiovascular Physiology, Department of Biological Sciences, Institute of Exact and Biological Sciences, Federal University of Ouro PretoOuro Preto, Brazil; Graduate Program in Biological Sciences - CBIOL/NUPEB, Federal University of Ouro PretoOuro Preto, Brazil
| | - Franciny A Paiva
- Laboratory of Cardiovascular Physiology, Department of Biological Sciences, Institute of Exact and Biological Sciences, Federal University of Ouro PretoOuro Preto, Brazil; Graduate Program in Biological Sciences - CBIOL/NUPEB, Federal University of Ouro PretoOuro Preto, Brazil
| | - Flávia C Müller-Ribeiro
- Laboratory of Hypertension, Institute of Biological Sciences, Department of Physiology and Biophysics, Federal University of Minas Gerais Belo Horizonte, Brazil
| | - Henrique M A Caldeira
- Laboratory of Cardiovascular Physiology, Department of Biological Sciences, Institute of Exact and Biological Sciences, Federal University of Ouro Preto Ouro Preto, Brazil
| | - Marco A P Fontes
- Laboratory of Hypertension, Institute of Biological Sciences, Department of Physiology and Biophysics, Federal University of Minas Gerais Belo Horizonte, Brazil
| | - Rodrigo C A de Menezes
- Laboratory of Cardiovascular Physiology, Department of Biological Sciences, Institute of Exact and Biological Sciences, Federal University of Ouro PretoOuro Preto, Brazil; Graduate Program in Biological Sciences - CBIOL/NUPEB, Federal University of Ouro PretoOuro Preto, Brazil
| | - Karina R Casali
- Laboratory of Biomedical Engineering, Institute of Science and Technology, Federal University of São Paulo São José dos Campos, Brazil
| | | | - Eleonora Tobaldini
- Department of Clinical Sciences and Community Health, IRCCS Ca' Granda Foundation, Ospedale Maggiore Policlinico, University of Milan Milan, Italy
| | - Monica Solbiati
- Department of Clinical Sciences and Community Health, IRCCS Ca' Granda Foundation, Ospedale Maggiore Policlinico, University of Milan Milan, Italy
| | - Nicola Montano
- Department of Clinical Sciences and Community Health, IRCCS Ca' Granda Foundation, Ospedale Maggiore Policlinico, University of Milan Milan, Italy
| | - Valdo J Dias Da Silva
- Department of Physiology, Institute of Biological and Natural Sciences, Federal University of Triângulo Mineiro Uberaba, Brazil
| | - Deoclécio A Chianca
- Laboratory of Cardiovascular Physiology, Department of Biological Sciences, Institute of Exact and Biological Sciences, Federal University of Ouro PretoOuro Preto, Brazil; Graduate Program in Biological Sciences - CBIOL/NUPEB, Federal University of Ouro PretoOuro Preto, Brazil
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Lother A, Hein L. Pharmacology of heart failure: From basic science to novel therapies. Pharmacol Ther 2016; 166:136-49. [PMID: 27456554 DOI: 10.1016/j.pharmthera.2016.07.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Accepted: 07/08/2016] [Indexed: 01/10/2023]
Abstract
Chronic heart failure is one of the leading causes for hospitalization in the United States and Europe, and is accompanied by high mortality. Current pharmacological therapy of chronic heart failure with reduced ejection fraction is largely based on compounds that inhibit the detrimental action of the adrenergic and the renin-angiotensin-aldosterone systems on the heart. More than one decade after spironolactone, two novel therapeutic principles have been added to the very recently released guidelines on heart failure therapy: the HCN-channel inhibitor ivabradine and the combined angiotensin and neprilysin inhibitor valsartan/sacubitril. New compounds that are in phase II or III clinical evaluation include novel non-steroidal mineralocorticoid receptor antagonists, guanylate cyclase activators or myosine activators. A variety of novel candidate targets have been identified and the availability of gene transfer has just begun to accelerate translation from basic science to clinical application. This review provides an overview of current pharmacology and pharmacotherapy in chronic heart failure at three stages: the updated clinical guidelines of the American Heart Association and the European Society of Cardiology, new drugs which are in clinical development, and finally innovative drug targets and their mechanisms in heart failure which are emerging from preclinical studies will be discussed.
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Affiliation(s)
- Achim Lother
- Institute of Experimental and Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Freiburg, Freiburg, Germany; Heart Center, Department of Cardiology and Angiology I, Faculty of Medicine, University of Freiburg, Freiburg, Germany.
| | - Lutz Hein
- Institute of Experimental and Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Freiburg, Freiburg, Germany; BIOSS Centre for Biological Signaling Studies, University of Freiburg, Freiburg, Germany.
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Tibbs GR, Posson DJ, Goldstein PA. Voltage-Gated Ion Channels in the PNS: Novel Therapies for Neuropathic Pain? Trends Pharmacol Sci 2016; 37:522-542. [DOI: 10.1016/j.tips.2016.05.002] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Revised: 03/24/2016] [Accepted: 05/03/2016] [Indexed: 12/19/2022]
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Dieks JK, Klehs S, Müller MJ, Paul T, Krause U. Adjunctive ivabradine in combination with amiodarone: A novel therapy for pediatric congenital junctional ectopic tachycardia. Heart Rhythm 2016; 13:1297-302. [DOI: 10.1016/j.hrthm.2016.03.015] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Indexed: 10/21/2022]
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