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Park JM, Seo YS, Kim SH, Kim HY, Kim MS, Lee MY. Impact of inhalation exposure to cigarette smoke on the pathogenesis of pulmonary hypertension primed by monocrotaline in rats. J Appl Toxicol 2024; 44:470-483. [PMID: 37876240 DOI: 10.1002/jat.4555] [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: 07/03/2023] [Revised: 09/26/2023] [Accepted: 09/26/2023] [Indexed: 10/26/2023]
Abstract
Extensive, long-term exposure to cigarette smoke (CS) was recently suggested to be a risk factor for pulmonary hypertension, although further validation is required. The vascular effects of CS share similarities with the etiology of pulmonary hypertension, including vascular inflammation and remodeling. Thus, we examined the influence of CS exposure on the pathogenesis of monocrotaline (MCT)-induced pulmonary hypertension, hypothesizing that smoking might accelerate the development of primed pulmonary hypertension. CS was generated from 3R4F reference cigarettes, and rats were exposed to CS by inhalation at total particulate matter concentrations of 100-300 μg/L for 4 h/day, 7 days/week for 4 weeks. Following 1 week of initial exposure, rats received 60 mg/kg MCT and were sacrificed and analyzed after an additional 3 weeks of exposure. MCT induced hypertrophy in pulmonary arterioles and increased the Fulton index, a measure of right ventricular hypertrophy. Additional CS exposure exacerbated arteriolar hypertrophy but did not further elevate the Fulton index. No significant alterations were observed in levels of endothelin-1 and vascular endothelial growth factor, or in hematological and serum biochemical parameters. Short-term inhalation exposure to CS exacerbated arteriolar hypertrophy in the lung, although this effect did not directly aggravate the overworked heart under the current experimental conditions.
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Affiliation(s)
- Jung-Min Park
- BK21 FOUR Team and Integrated Research Institute for Drug Development, College of Pharmacy, Dongguk University, Goyang-si, Gyeonggi-do, Republic of Korea
| | - Yoon-Seok Seo
- BK21 FOUR Team and Integrated Research Institute for Drug Development, College of Pharmacy, Dongguk University, Goyang-si, Gyeonggi-do, Republic of Korea
| | - Sung-Hwan Kim
- Inhalation Toxicology Research Group, Korea Institute of Toxicology, Jeongeup-si, Jeollabuk-do, Republic of Korea
| | - Hyeon-Young Kim
- Inhalation Toxicology Research Group, Korea Institute of Toxicology, Jeongeup-si, Jeollabuk-do, Republic of Korea
| | - Min-Seok Kim
- Inhalation Toxicology Research Group, Korea Institute of Toxicology, Jeongeup-si, Jeollabuk-do, Republic of Korea
| | - Moo-Yeol Lee
- BK21 FOUR Team and Integrated Research Institute for Drug Development, College of Pharmacy, Dongguk University, Goyang-si, Gyeonggi-do, Republic of Korea
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2
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Electrical Remodeling in Right Ventricular Failure Due to Pulmonary Hypertension: Unraveling Novel Therapeutic Targets. Int J Mol Sci 2023; 24:ijms24054633. [PMID: 36902065 PMCID: PMC10003421 DOI: 10.3390/ijms24054633] [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: 01/21/2023] [Revised: 02/23/2023] [Accepted: 02/25/2023] [Indexed: 03/05/2023] Open
Abstract
Arrhythmias in the setting of right-ventricular (RV) remodeling contribute to majority of deaths in patients with pulmonary hypertension. However, the underlying mechanism of electrical remodeling remains elusive, especially ventricular arrhythmias. Here, we analyzed the RV transcriptome of pulmonary arterial hypertension (PAH) patients with compensated RV or decompensated RV and identified 8 and 45 differentially expressed genes known to be involved in regulating the electrophysiological properties of excitation and contraction of cardiac myocytes, respectively. Transcripts encoding voltage-gated Ca2+ and Na+ channels were notably decreased in PAH patients with decompensated RV, along with significant dysregulation of KV and Kir channels. We further showed similarity of the RV channelome signature with two well-known animal models of PAH, monocrotaline (MCT)- and Sugen-hypoxia (SuHx)-treated rats. We identified 15 common transcripts among MCT, SuHx, and PAH patients with decompensated RV failure. In addition, data-driven drug repurposing using the channelome signature of PAH patients with decompensated RV failure predicted drug candidates that may reverse the altered gene expression. Comparative analysis provided further insight into clinical relevance and potential preclinical therapeutic studies targeting mechanisms involved in arrhythmogenesis.
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3
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Bandorski D, Heibel S, Höltgen R, Bogossian H, Ghofrani HA, Zarse M, Gall H. Incidence and prognostic significance of malignant arrhythmias during (repetitive) Holter electrocardiograms in patients with pulmonary hypertension. Front Cardiovasc Med 2023; 10:1084051. [PMID: 37139131 PMCID: PMC10150006 DOI: 10.3389/fcvm.2023.1084051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2022] [Accepted: 03/20/2023] [Indexed: 05/05/2023] Open
Abstract
Background In patients with pulmonary hypertension (PH), increased pulmonary vascular resistance (PVR) may lead to increased right ventricular afterload and cardiac remodelling, potentially providing the substrate for ventricular arrhythmias. Studies dealing with long term monitoring of patients with PH are rare. The present study evaluated the incidence and the types of arrhythmias retrospectively recorded by Holter ECG in patients with newly detected PH during a long-term Holter ECG follow-up. Moreover, their impact on patient survival was evaluated. Patients and methods Medical records were screened for demographic data, aetiology of PH, incidence of coronary heart disease, level of brain natriuretic peptide (BNP), results from Holter ECG monitoring, 6-minute walk test distance, echocardiographic data and hemodynamic data derived from right heart catheterization. Two subgroups were analyzed: 1. patients (n = 65) with PH (group 1 + 4) and derivation of at least 1 Holter ECG within 12 months from initial detection of PH and 2. patients (all PH etiologies, n = 59) with 3 follow-up Holter ECGs. The frequency and complexity of premature ventricular contractions (PVC) was classified into "lower" and "higher" (=non sustained ventricular tachycardia, nsVT) burden. Results Holter ECG revealed sinus rhythm (SR) in most of the patients (n = 60). Incidence of atrial fibrillation (AFib) was low (n = 4). Patients with premature atrial contractions (PAC) tend to have a shorter period of survival (p = 0.098), PVC were not correlated with significant survival differences. During follow-up PAC and PVC were common in all PH groups. Holter ECG revealed non sustained ventricular tachycardia in 19/59 patients [(32.2%); n = 6 during first Holter-ECG, n = 13 during second/third Holter-ECG]. In all patients suffering from nsVT during follow-up previous Holter ECG revealed multiform/repetitive PVC. PVC burden was not linked to differences in systolic pulmonary arterial pressure, right atrial pressure, brain natriuretic peptide and results of six-minute walk test. Conclusion Patients with PAC tend to have a shortened survival. None of the evaluated parameters (BNP, TAPSE, sPAP) was correlated with the development of arrhythmias. Patients with multiform/repetitive PVC seem to be at risk for ventricular arrhythmias.
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Affiliation(s)
- Dirk Bandorski
- Faculty of Medicine, Semmelweis University, Budapest, Hungary
- Correspondence: Dirk Bandorski
| | - Sebastian Heibel
- Medical Clinic III, Sana Klinikum Offenbach, Offenbach am Main, Germany
| | - Reinhard Höltgen
- Klinikum Westmünsterland, St. Agnes-Hospital Bocholt-Rhede, Bocholt, Germany
| | | | - Hossein Ardeschir Ghofrani
- The German Center for Lung Research (DZL), University of Giessen and Marburg Lung Center (UGMLC), Giessen, Germany
| | - Markus Zarse
- Cardiology Department, School of Medicine, Witten/Herdecke University, Witten, Germany
| | - Henning Gall
- The German Center for Lung Research (DZL), University of Giessen and Marburg Lung Center (UGMLC), Giessen, Germany
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4
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Wu J, Liu T, Shi S, Fan Z, Hiram R, Xiong F, Cui B, Su X, Chang R, Zhang W, Yan M, Tang Y, Huang H, Wu G, Huang C. Dapagliflozin reduces the vulnerability of rats with pulmonary arterial hypertension-induced right heart failure to ventricular arrhythmia by restoring calcium handling. Cardiovasc Diabetol 2022; 21:197. [PMID: 36171554 PMCID: PMC9516842 DOI: 10.1186/s12933-022-01614-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 09/01/2022] [Indexed: 12/20/2022] Open
Abstract
Background Malignant ventricular arrhythmia (VA) is a major contributor to sudden cardiac death (SCD) in patients with pulmonary arterial hypertension (PAH)-induced right heart failure (RHF). Recently, dapagliflozin (DAPA), a sodium/glucose cotransporter-2 inhibitor (SGLT2i), has been found to exhibit cardioprotective effects in patients with left ventricular systolic dysfunction. In this study, we examined the effects of DAPA on VA vulnerability in a rat model of PAH-induced RHF. Methods Rats randomly received monocrotaline (MCT, 60 mg/kg) or vehicle via a single intraperitoneal injection. A day later, MCT-injected rats were randomly treated with placebo, low-dose DAPA (1 mg/kg/day), or high-dose (3 mg/kg/day) DAPA orally for 35 days. Echocardiographic analysis, haemodynamic experiments, and histological assessments were subsequently performed to confirm the presence of PAH-induced RHF. Right ventricle (RV) expression of calcium (Ca2+) handling proteins were detected via Western blotting. RV expression of connexin 43 (Cx43) was determined via immunohistochemical staining. An optical mapping study was performed to assess the electrophysiological characteristics in isolated hearts. Cellular Ca2+ imaging from RV cardiomyocytes (RVCMs) was recorded using Fura-2 AM or Fluo-4 AM. Results High-dose DAPA treatment attenuated RV structural remodelling, improved RV function, alleviated Cx43 remodelling, increased the conduction velocity, restored the expression of key Ca2+ handling proteins, increased the threshold for Ca2+ and action potential duration (APD) alternans, decreased susceptibility to spatially discordant APD alternans and spontaneous Ca2+ events, promoted cellular Ca2+ handling, and reduced VA vulnerability in PAH-induced RHF rats. Low-dose DAPA treatment also showed antiarrhythmic effects in hearts with PAH-induced RHF, although with a lower level of efficacy. Conclusion DAPA administration reduced VA vulnerability in rats with PAH-induced RHF by improving RVCM Ca2+ handling. Supplementary Information The online version contains supplementary material available at 10.1186/s12933-022-01614-5.
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Affiliation(s)
- Jinchun Wu
- Department of Cardiology, Renmin Hospital of Wuhan University, No. 238 Jiefang Road, Wuhan, 430060, People's Republic of China.,Cardiovascular Research Institute, Wuhan University, 238 Jiefang Road, Wuhan, 430060, People's Republic of China.,Hubei Key Laboratory of Cardiology, 238 Jiefang Road, Wuhan, 430060, People's Republic of China.,Department of Cardiology, Qinghai Provincial People's Hospital, No.2 Gong He Road, Xining, 810007, People's Republic of China
| | - Tao Liu
- Department of Cardiology, Renmin Hospital of Wuhan University, No. 238 Jiefang Road, Wuhan, 430060, People's Republic of China. .,Cardiovascular Research Institute, Wuhan University, 238 Jiefang Road, Wuhan, 430060, People's Republic of China. .,Hubei Key Laboratory of Cardiology, 238 Jiefang Road, Wuhan, 430060, People's Republic of China.
| | - Shaobo Shi
- Department of Cardiology, Renmin Hospital of Wuhan University, No. 238 Jiefang Road, Wuhan, 430060, People's Republic of China.,Cardiovascular Research Institute, Wuhan University, 238 Jiefang Road, Wuhan, 430060, People's Republic of China.,Hubei Key Laboratory of Cardiology, 238 Jiefang Road, Wuhan, 430060, People's Republic of China
| | - Zhixing Fan
- Department of Cardiology, Renmin Hospital of Wuhan University, No. 238 Jiefang Road, Wuhan, 430060, People's Republic of China.,Cardiovascular Research Institute, Wuhan University, 238 Jiefang Road, Wuhan, 430060, People's Republic of China.,Hubei Key Laboratory of Cardiology, 238 Jiefang Road, Wuhan, 430060, People's Republic of China
| | - Roddy Hiram
- Department of Medicine, Faculty of Medicine, Montreal Heart Institute (MHI), Université de Montréal, Montreal, QC, Canada
| | - Feng Xiong
- Department of Medicine, Faculty of Medicine, Montreal Heart Institute (MHI), Université de Montréal, Montreal, QC, Canada
| | - Bo Cui
- Department of Cardiology, Renmin Hospital of Wuhan University, No. 238 Jiefang Road, Wuhan, 430060, People's Republic of China.,Cardiovascular Research Institute, Wuhan University, 238 Jiefang Road, Wuhan, 430060, People's Republic of China.,Hubei Key Laboratory of Cardiology, 238 Jiefang Road, Wuhan, 430060, People's Republic of China
| | - Xiaoling Su
- Department of Cardiology, Qinghai Provincial People's Hospital, No.2 Gong He Road, Xining, 810007, People's Republic of China
| | - Rong Chang
- Department of Cardiology, Shenzhen Longhua District Central Hospital, The Affiliated Central Hospital of Shenzhen Longhua District, Guangdong Medical University, No. 187 Guanlan Road, Longhua District, Shenzhen, 518109, China
| | - Wei Zhang
- Department of Cardiology, Renmin Hospital of Wuhan University, No. 238 Jiefang Road, Wuhan, 430060, People's Republic of China.,Cardiovascular Research Institute, Wuhan University, 238 Jiefang Road, Wuhan, 430060, People's Republic of China.,Hubei Key Laboratory of Cardiology, 238 Jiefang Road, Wuhan, 430060, People's Republic of China
| | - Min Yan
- Department of Cardiology, Renmin Hospital of Wuhan University, No. 238 Jiefang Road, Wuhan, 430060, People's Republic of China.,Cardiovascular Research Institute, Wuhan University, 238 Jiefang Road, Wuhan, 430060, People's Republic of China.,Hubei Key Laboratory of Cardiology, 238 Jiefang Road, Wuhan, 430060, People's Republic of China
| | - Yanhong Tang
- Department of Cardiology, Renmin Hospital of Wuhan University, No. 238 Jiefang Road, Wuhan, 430060, People's Republic of China.,Cardiovascular Research Institute, Wuhan University, 238 Jiefang Road, Wuhan, 430060, People's Republic of China.,Hubei Key Laboratory of Cardiology, 238 Jiefang Road, Wuhan, 430060, People's Republic of China
| | - He Huang
- Department of Cardiology, Renmin Hospital of Wuhan University, No. 238 Jiefang Road, Wuhan, 430060, People's Republic of China.,Cardiovascular Research Institute, Wuhan University, 238 Jiefang Road, Wuhan, 430060, People's Republic of China.,Hubei Key Laboratory of Cardiology, 238 Jiefang Road, Wuhan, 430060, People's Republic of China
| | - Gang Wu
- Department of Cardiology, Renmin Hospital of Wuhan University, No. 238 Jiefang Road, Wuhan, 430060, People's Republic of China. .,Cardiovascular Research Institute, Wuhan University, 238 Jiefang Road, Wuhan, 430060, People's Republic of China. .,Hubei Key Laboratory of Cardiology, 238 Jiefang Road, Wuhan, 430060, People's Republic of China.
| | - Congxin Huang
- Department of Cardiology, Renmin Hospital of Wuhan University, No. 238 Jiefang Road, Wuhan, 430060, People's Republic of China. .,Cardiovascular Research Institute, Wuhan University, 238 Jiefang Road, Wuhan, 430060, People's Republic of China. .,Hubei Key Laboratory of Cardiology, 238 Jiefang Road, Wuhan, 430060, People's Republic of China.
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5
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Pham T, Tran K, Taberner AJ, Loiselle DS, Han JC. Crossbridge thermodynamics in pulmonary arterial hypertensive right-ventricular failure. J Appl Physiol (1985) 2022; 132:1338-1349. [PMID: 35482327 PMCID: PMC9208464 DOI: 10.1152/japplphysiol.00014.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Right-ventricular (RV) failure is an event consequent to pathological RV hypertrophy commonly resulting from pulmonary arterial hypertension. This pathology is well characterized by RV diastolic dysfunction, impaired ejection, and reduced mechanical efficiency. However, whether the dynamic stiffness and cross-bridge thermodynamics in the failing RV muscles are compromised remains uncertain. Pulmonary arterial hypertension was induced in the rat by injection of monocrotaline, and RV trabeculae were isolated from RV failing rats. Cross-bridge mechano-energetics were characterized by subjecting the trabeculae to two interventions: 1) force-length work-loop contractions over a range of afterloads while measuring heat output, followed by careful partitioning of heat components into activation heat and cross-bridge heat to separately assess mechanical efficiency and cross-bridge efficiency, and 2) sinusoidal-perturbation of muscle length while trabeculae were actively contracting to interrogate cross-bridge dynamic stiffness. We found that reduced mechanical efficiency is correlated with increased passive stress, reduced shortening, and elevated activation heat. In contrast, the thermodynamics, specifically the efficiency of, and the stiffness characteristics of, cross bridges did not differ between the control and failing trabeculae and were not correlated with elevated passive stress or reduced shortening. We thus conclude that, despite diastolic dysfunction and mechanical inefficiency, cross-bridge stiffness and thermodynamics are unaffected in RV failure following pulmonary arterial hypertension. NEW & NOTEWORTHY This study characterizes cross-bridge mechano-energetics and dynamic stiffness of right-ventricular trabeculae isolated from a rat model of pulmonary hypertensive right-ventricular failure. Failing trabeculae showed increased passive force but normal active force. Their lower mechanical efficiency is found to be driven by an increase in the energy expenditure arising from contractile activation. This does not reflect a change in their cross-bridge stiffness and efficiency.
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Affiliation(s)
- Toan Pham
- Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand
| | - Kenneth Tran
- Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand
| | - Andrew J Taberner
- Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand.,Department of Engineering Science, The University of Auckland, Auckland, New Zealand
| | - Denis S Loiselle
- Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand.,Department of Engineering Science, The University of Auckland, Auckland, New Zealand
| | - June-Chiew Han
- Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand
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6
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Tanaka S, Yamamoto T, Mikawa M, Nawata J, Fujii S, Nakamura Y, Kato T, Fukuda M, Suetomi T, Uchinoumi H, Oda T, Okuda S, Okamura T, Kobayashi S, Yano. M. Stabilization of RyR2 maintains right ventricular function, reduces the development of ventricular arrhythmias, and improves prognosis in pulmonary hypertension. Heart Rhythm 2022; 19:986-997. [DOI: 10.1016/j.hrthm.2022.02.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2021] [Revised: 01/18/2022] [Accepted: 02/01/2022] [Indexed: 02/01/2023]
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7
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Strauss B, Bisserier M, Obus E, Katz MG, Fargnoli A, Cacheux M, Akar JG, Hummel JP, Hadri L, Sassi Y, Akar FG. Right predominant electrical remodeling in a pure model of pulmonary hypertension promotes reentrant arrhythmias. Heart Rhythm 2022; 19:113-124. [PMID: 34563688 PMCID: PMC8742785 DOI: 10.1016/j.hrthm.2021.09.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 09/08/2021] [Accepted: 09/19/2021] [Indexed: 01/03/2023]
Abstract
BACKGROUND Electrophysiological (EP) properties have been studied mainly in the monocrotaline model of pulmonary arterial hypertension (PAH). Findings are confounded by major extrapulmonary toxicities, which preclude the ability to draw definitive conclusions regarding the role of PAH per se in EP remodeling. OBJECTIVE The purpose of this study was to investigate the EP substrate and arrhythmic vulnerability of a new model of PAH that avoids extracardiopulmonary toxicities. METHODS Sprague-Dawley rats underwent left pneumonectomy (Pn) followed by injection of the vascular endothelial growth factor inhibitor Sugen-5416 (Su/Pn). Five weeks later, cardiac magnetic resonance imaging was performed in vivo, optical action potential (AP) mapping ex vivo, and molecular analyses in vitro. RESULTS Su/Pn rats exhibited right ventricular (RV) hypertrophy and were highly prone to pacing-induced ventricular tachycardia/fibrillation (VT/VF). Underlying this susceptibility was disproportionate RV-sided prolongation of AP duration, which promoted formation of right-sided AP alternans at physiological rates. While propagation was impaired at all rates in Su/Pn rats, the extent of conduction slowing was most severe immediately before the emergence of interventricular lines of block and onset of VT/VF. Measurement of the cardiac wavelength revealed a decrease in Su/Pn relative to control. Nav1.5 and total connexin 43 expression was not altered, while connexin 43 phosphorylation was decreased in PAH. Col1a1 and Col3a1 transcripts were upregulated coinciding with myocardial fibrosis. Once generated, VT/VF was sustained by multiple reentrant circuits with a lower frequency of RV activation due to wavebreak formation. CONCLUSION In this pure model of PAH, we document RV-predominant remodeling that promotes multiwavelet reentry underlying VT. The Su/Pn model represents a severe form of PAH that allows the study of EP properties without the confounding influence of extrapulmonary toxicity.
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Affiliation(s)
- Benjamin Strauss
- Electro-biology & Arrhythmia Therapeutics Laboratory, Cardiovascular Research Center, Yale University
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai
| | - Malik Bisserier
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai
| | - Emerson Obus
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai
| | - Michael G. Katz
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai
| | - Anthony Fargnoli
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai
| | - Marine Cacheux
- Electro-biology & Arrhythmia Therapeutics Laboratory, Cardiovascular Research Center, Yale University
| | - Joseph G. Akar
- Electro-biology & Arrhythmia Therapeutics Laboratory, Cardiovascular Research Center, Yale University
| | - James P Hummel
- Electro-biology & Arrhythmia Therapeutics Laboratory, Cardiovascular Research Center, Yale University
| | - Lahouaria Hadri
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai
| | - Yassine Sassi
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai
- Center for Vascular and Heart Research, Fralin Biomedical research Institute at Virginia Tech Carilion
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University
| | - Fadi G. Akar
- Electro-biology & Arrhythmia Therapeutics Laboratory, Cardiovascular Research Center, Yale University
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8
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Udovicic M, Sever M, Kavur L, Loncaric K, Barisic I, Balenovic D, Zivanovic Posilovic G, Strinic D, Uzun S, Batelja Vuletic L, Sikiric S, Skrtic A, Drmic D, Boban Blagaic A, Lovric Bencic M, Seiwerth S, Sikiric P. Stable Gastric Pentadecapeptide BPC 157 Therapy for Monocrotaline-Induced Pulmonary Hypertension in Rats Leads to Prevention and Reversal. Biomedicines 2021; 9:biomedicines9070822. [PMID: 34356886 PMCID: PMC8301325 DOI: 10.3390/biomedicines9070822] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 06/26/2021] [Accepted: 07/12/2021] [Indexed: 02/07/2023] Open
Abstract
Background. Monocrotaline selectively injures the lung's vascular endothelium and induces pulmonary arterial hypertension. The stable gastric pentadecapeptide BPC 157 acts as a prototype cytoprotective agent that maintains endothelium, and its application may be a novel therapy. Besides, BPC 157 prevents and reverses thrombosis formation, maintains platelet function, alleviates peripheral vascular occlusion disturbances, and has anti-arrhythmic and anti-inflammatory effects. Monocrotaline-induced pulmonary arterial hypertension in rats (wall thickness, total vessel area, heart frequency, QRS axis deviation, QT interval prolongation, increase in right ventricle systolic pressure and bodyweight loss) can be counteracted with early or delayed BPC 157 therapy. Methods and Results. After monocrotaline (80 mg/kg subcutaneously), BPC 157 (10 μg/kg or 10 ng/kg, days 1-14 or days 1-30 (early regimens), or days 14-30 (delayed regimen)) was given once daily intraperitoneally (last application 24 h before sacrifice) or continuously in drinking water until sacrifice (day 14 or 30). Without therapy, the outcome was the full monocrotaline syndrome, marked by right-side heart hypertrophy and massive thickening of the precapillary artery's smooth muscle layer, clinical deterioration, and sometimes death due to pulmonary hypertension and right-heart failure during the 4th week after monocrotaline injection. With all BPC 157 regimens, monocrotaline-induced pulmonary arterial hypertension (including all disturbed parameters) was counteracted, and consistent beneficial effects were documented during the whole course of the disease. Pulmonary hypertension was not even developed (early regimens) as quickly as the advanced pulmonary hypertension was rapidly attenuated and then completely eliminated (delayed regimen). Conclusions. Thus, pentadecapeptide BPC 157 prevents and counteracts monocrotaline-induced pulmonary arterial hypertension and cor pulmonale in rats.
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Affiliation(s)
- Mario Udovicic
- Department of Pharmacology, School of Medicine, University of Zagreb, Salata 11, P.O. Box 916, 10000 Zagreb, Croatia; (M.U.); (M.S.); (L.K.); (K.L.); (I.B.); (D.B.); (G.Z.P.); (D.S.); (S.U.); (D.D.); (A.B.B.); (M.L.B.)
| | - Marko Sever
- Department of Pharmacology, School of Medicine, University of Zagreb, Salata 11, P.O. Box 916, 10000 Zagreb, Croatia; (M.U.); (M.S.); (L.K.); (K.L.); (I.B.); (D.B.); (G.Z.P.); (D.S.); (S.U.); (D.D.); (A.B.B.); (M.L.B.)
| | - Lovro Kavur
- Department of Pharmacology, School of Medicine, University of Zagreb, Salata 11, P.O. Box 916, 10000 Zagreb, Croatia; (M.U.); (M.S.); (L.K.); (K.L.); (I.B.); (D.B.); (G.Z.P.); (D.S.); (S.U.); (D.D.); (A.B.B.); (M.L.B.)
| | - Kristina Loncaric
- Department of Pharmacology, School of Medicine, University of Zagreb, Salata 11, P.O. Box 916, 10000 Zagreb, Croatia; (M.U.); (M.S.); (L.K.); (K.L.); (I.B.); (D.B.); (G.Z.P.); (D.S.); (S.U.); (D.D.); (A.B.B.); (M.L.B.)
| | - Ivan Barisic
- Department of Pharmacology, School of Medicine, University of Zagreb, Salata 11, P.O. Box 916, 10000 Zagreb, Croatia; (M.U.); (M.S.); (L.K.); (K.L.); (I.B.); (D.B.); (G.Z.P.); (D.S.); (S.U.); (D.D.); (A.B.B.); (M.L.B.)
| | - Diana Balenovic
- Department of Pharmacology, School of Medicine, University of Zagreb, Salata 11, P.O. Box 916, 10000 Zagreb, Croatia; (M.U.); (M.S.); (L.K.); (K.L.); (I.B.); (D.B.); (G.Z.P.); (D.S.); (S.U.); (D.D.); (A.B.B.); (M.L.B.)
| | - Gordana Zivanovic Posilovic
- Department of Pharmacology, School of Medicine, University of Zagreb, Salata 11, P.O. Box 916, 10000 Zagreb, Croatia; (M.U.); (M.S.); (L.K.); (K.L.); (I.B.); (D.B.); (G.Z.P.); (D.S.); (S.U.); (D.D.); (A.B.B.); (M.L.B.)
| | - Dean Strinic
- Department of Pharmacology, School of Medicine, University of Zagreb, Salata 11, P.O. Box 916, 10000 Zagreb, Croatia; (M.U.); (M.S.); (L.K.); (K.L.); (I.B.); (D.B.); (G.Z.P.); (D.S.); (S.U.); (D.D.); (A.B.B.); (M.L.B.)
| | - Sandra Uzun
- Department of Pharmacology, School of Medicine, University of Zagreb, Salata 11, P.O. Box 916, 10000 Zagreb, Croatia; (M.U.); (M.S.); (L.K.); (K.L.); (I.B.); (D.B.); (G.Z.P.); (D.S.); (S.U.); (D.D.); (A.B.B.); (M.L.B.)
| | - Lovorka Batelja Vuletic
- Department of Pathology, School of Medicine, University of Zagreb, Salata 11, P.O. Box 916, 10000 Zagreb, Croatia; (L.B.V.); (S.S.); (S.S.)
| | - Suncana Sikiric
- Department of Pathology, School of Medicine, University of Zagreb, Salata 11, P.O. Box 916, 10000 Zagreb, Croatia; (L.B.V.); (S.S.); (S.S.)
| | - Anita Skrtic
- Department of Pathology, School of Medicine, University of Zagreb, Salata 11, P.O. Box 916, 10000 Zagreb, Croatia; (L.B.V.); (S.S.); (S.S.)
- Correspondence: (A.S.); (P.S.); Tel.: +385-1-4566-980 (A.S.); +385-1-4566-833 (P.S.); Fax: +385-1-4920-050 (A.S. & P.S.)
| | - Domagoj Drmic
- Department of Pharmacology, School of Medicine, University of Zagreb, Salata 11, P.O. Box 916, 10000 Zagreb, Croatia; (M.U.); (M.S.); (L.K.); (K.L.); (I.B.); (D.B.); (G.Z.P.); (D.S.); (S.U.); (D.D.); (A.B.B.); (M.L.B.)
| | - Alenka Boban Blagaic
- Department of Pharmacology, School of Medicine, University of Zagreb, Salata 11, P.O. Box 916, 10000 Zagreb, Croatia; (M.U.); (M.S.); (L.K.); (K.L.); (I.B.); (D.B.); (G.Z.P.); (D.S.); (S.U.); (D.D.); (A.B.B.); (M.L.B.)
| | - Martina Lovric Bencic
- Department of Pharmacology, School of Medicine, University of Zagreb, Salata 11, P.O. Box 916, 10000 Zagreb, Croatia; (M.U.); (M.S.); (L.K.); (K.L.); (I.B.); (D.B.); (G.Z.P.); (D.S.); (S.U.); (D.D.); (A.B.B.); (M.L.B.)
| | - Sven Seiwerth
- Department of Pathology, School of Medicine, University of Zagreb, Salata 11, P.O. Box 916, 10000 Zagreb, Croatia; (L.B.V.); (S.S.); (S.S.)
| | - Predrag Sikiric
- Department of Pharmacology, School of Medicine, University of Zagreb, Salata 11, P.O. Box 916, 10000 Zagreb, Croatia; (M.U.); (M.S.); (L.K.); (K.L.); (I.B.); (D.B.); (G.Z.P.); (D.S.); (S.U.); (D.D.); (A.B.B.); (M.L.B.)
- Correspondence: (A.S.); (P.S.); Tel.: +385-1-4566-980 (A.S.); +385-1-4566-833 (P.S.); Fax: +385-1-4920-050 (A.S. & P.S.)
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9
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Stam K, Clauss S, Taverne YJHJ, Merkus D. Chronic Thromboembolic Pulmonary Hypertension - What Have We Learned From Large Animal Models. Front Cardiovasc Med 2021; 8:574360. [PMID: 33937352 PMCID: PMC8085273 DOI: 10.3389/fcvm.2021.574360] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Accepted: 03/08/2021] [Indexed: 12/21/2022] Open
Abstract
Chronic thrombo-embolic pulmonary hypertension (CTEPH) develops in a subset of patients after acute pulmonary embolism. In CTEPH, pulmonary vascular resistance, which is initially elevated due to the obstructions in the larger pulmonary arteries, is further increased by pulmonary microvascular remodeling. The increased afterload of the right ventricle (RV) leads to RV dilation and hypertrophy. This RV remodeling predisposes to arrhythmogenesis and RV failure. Yet, mechanisms involved in pulmonary microvascular remodeling, processes underlying the RV structural and functional adaptability in CTEPH as well as determinants of the susceptibility to arrhythmias such as atrial fibrillation in the context of CTEPH remain incompletely understood. Several large animal models with critical clinical features of human CTEPH and subsequent RV remodeling have relatively recently been developed in swine, sheep, and dogs. In this review we will discuss the current knowledge on the processes underlying development and progression of CTEPH, and on how animal models can help enlarge understanding of these processes.
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Affiliation(s)
- Kelly Stam
- Department of Cardiology, Erasmus University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Sebastian Clauss
- Department of Medicine I, University Hospital Munich, Ludwig-Maximilians University Munich, Munich, Germany.,Institute of Surgical Research at the Walter-Brendel-Centre of Experimental Medicine, University Hospital, LMU Munich, Munich, Germany.,DZHK (German Centre for Cardiovascular Research), Partner Site Munich, Munich Heart Alliance, Munich, Germany
| | - Yannick J H J Taverne
- Department of Cardiothoracic Surgery, Erasmus University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Daphne Merkus
- Department of Cardiology, Erasmus University Medical Center Rotterdam, Rotterdam, Netherlands.,Institute of Surgical Research at the Walter-Brendel-Centre of Experimental Medicine, University Hospital, LMU Munich, Munich, Germany.,DZHK (German Centre for Cardiovascular Research), Partner Site Munich, Munich Heart Alliance, Munich, Germany
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10
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Gupta A, Fei YD, Kim TY, Xie A, Batai K, Greener I, Tang H, Ciftci-Yilmaz S, Juneman E, Indik JH, Shi G, Christensen J, Gupta G, Hillery C, Kansal MM, Parikh DS, Zhou T, Yuan JXJ, Kanthi Y, Bronk P, Koren G, Kittles R, Duarte JD, Garcia JGN, Machado RF, Dudley SC, Choi BR, Desai AA. IL-18 mediates sickle cell cardiomyopathy and ventricular arrhythmias. Blood 2021; 137:1208-1218. [PMID: 33181835 PMCID: PMC7933768 DOI: 10.1182/blood.2020005944] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Accepted: 10/21/2020] [Indexed: 12/16/2022] Open
Abstract
Previous reports indicate that IL18 is a novel candidate gene for diastolic dysfunction in sickle cell disease (SCD)-related cardiomyopathy. We hypothesize that interleukin-18 (IL-18) mediates the development of cardiomyopathy and ventricular tachycardia (VT) in SCD. Compared with control mice, a humanized mouse model of SCD exhibited increased cardiac fibrosis, prolonged duration of action potential, higher VT inducibility in vivo, higher cardiac NF-κB phosphorylation, and higher circulating IL-18 levels, as well as reduced voltage-gated potassium channel expression, which translates to reduced transient outward potassium current (Ito) in isolated cardiomyocytes. Administering IL-18 to isolated mouse hearts resulted in VT originating from the right ventricle and further reduced Ito in SCD mouse cardiomyocytes. Sustained IL-18 inhibition via IL-18-binding protein resulted in decreased cardiac fibrosis and NF-κB phosphorylation, improved diastolic function, normalized electrical remodeling, and attenuated IL-18-mediated VT in SCD mice. Patients with SCD and either myocardial fibrosis or increased QTc displayed greater IL18 gene expression in peripheral blood mononuclear cells (PBMCs), and QTc was strongly correlated with plasma IL-18 levels. PBMC-derived IL18 gene expression was increased in patients who did not survive compared with those who did. IL-18 is a mediator of sickle cell cardiomyopathy and VT in mice and a novel therapeutic target in patients at risk for sudden death.
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Affiliation(s)
- Akash Gupta
- Department of Medicine, University of Arizona Health Sciences Center, University of Arizona, Tucson, AZ
| | - Yu-Dong Fei
- Department of Medicine, Indiana University, Indianapolis, IN
- Department of Cardiology, XinHua Hospital Affiliated to Shanghai JiaoTong University School of Medicine, Shanghai, China
| | - Tae Yun Kim
- Cardiovascular Research Center, Department of Medicine, Rhode Island Hospital and Alpert Medical School of Brown University, Providence, RI
| | - An Xie
- Department of Medicine, University of Minnesota, Minneapolis, MN
| | - Ken Batai
- Department of Surgery, University of Arizona Health Sciences Center, University of Arizona, Tucson, AZ
| | - Ian Greener
- Department of Medicine, University of Illinois Hospitals and Health Sciences System, Chicago, IL
| | - Haiyang Tang
- Department of Medicine, University of Arizona, Tucson, AZ
| | | | - Elizabeth Juneman
- Department of Medicine, University of Arizona Health Sciences Center, University of Arizona, Tucson, AZ
| | - Julia H Indik
- Department of Medicine, University of Arizona Health Sciences Center, University of Arizona, Tucson, AZ
| | - Guanbin Shi
- Cardiovascular Research Center, Department of Medicine, Rhode Island Hospital and Alpert Medical School of Brown University, Providence, RI
| | - Jared Christensen
- Cardiovascular Research Center, Department of Medicine, Rhode Island Hospital and Alpert Medical School of Brown University, Providence, RI
| | - Geetanjali Gupta
- Department of Medicine, University of Arizona Health Sciences Center, University of Arizona, Tucson, AZ
| | - Cheryl Hillery
- Department of Pediatrics, University of Pittsburgh, Pittsburgh, PA
| | - Mayank M Kansal
- Department of Medicine, University of Illinois Hospitals and Health Sciences System, Chicago, IL
| | - Devang S Parikh
- Department of Medicine, University of Illinois Hospitals and Health Sciences System, Chicago, IL
| | - Tong Zhou
- Department of Physiology and Cell Biology, University of Nevada, Reno, NV
| | - Jason X-J Yuan
- Department of Medicine, University of California, San Diego, La Jolla, CA
| | - Yogendra Kanthi
- Laboratory of Vascular Thrombosis & Inflammation, National Heart, Lung and Blood Institute, Bethesda, MD
| | - Peter Bronk
- Cardiovascular Research Center, Department of Medicine, Rhode Island Hospital and Alpert Medical School of Brown University, Providence, RI
| | - Gideon Koren
- Cardiovascular Research Center, Department of Medicine, Rhode Island Hospital and Alpert Medical School of Brown University, Providence, RI
| | - Rick Kittles
- Department of Population Science, City of Hope Medical Center, Duarte, CA; and
| | - Julio D Duarte
- Department of Pharmacotherapy and Translational Research, University of Florida, Gainesville, FL
| | - Joe G N Garcia
- Department of Medicine, University of Arizona Health Sciences Center, University of Arizona, Tucson, AZ
| | | | - Samuel C Dudley
- Department of Medicine, University of Minnesota, Minneapolis, MN
| | - Bum-Rak Choi
- Cardiovascular Research Center, Department of Medicine, Rhode Island Hospital and Alpert Medical School of Brown University, Providence, RI
| | - Ankit A Desai
- Department of Medicine, Indiana University, Indianapolis, IN
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11
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Zou S, Cen Z, Jia R, Lu S, Hao Y, Cui K. Electrophysiological study and radiofrequency ablation of hemodynamically-instable ventricular arrhythmias in a patient with pulmonary hypertension: A case report. Medicine (Baltimore) 2021; 100:e24896. [PMID: 33663121 PMCID: PMC7909233 DOI: 10.1097/md.0000000000024896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Accepted: 02/04/2021] [Indexed: 02/05/2023] Open
Abstract
INTRODUCTION Hemodynamically-instable ventricular arrhythmias (VAs) are rare in patients with pulmonary hypertension (PH). To the best of our knowledge, only 1 case has been reported so far. Moreover, the pathogenesis of this kind of arrhythmia remains obscured and its treatment is challenging. Here we report another case and presented the substrate for VAs initiation and therapeutic effect of radiofrequency ablation. PATIENT CONCERNS This is a 57-year-old man who presented paroxysmal palpitation associated with presyncope at rest. Surface electrocardiogram (ECG) revealed frequent ventricular premature contractions and non-sustained ventricular tachycardia when symptoms occurred. He also had a history of severe PH which was secondary to atrial septal defect and partial anomalous pulmonary venous drainage and suffered from obvious dyspnea when climbing stairs World Health Organization Class III (WHO Class III). DIAGNOSIS Hemodynamically-instable VAs associated with severe PH. INTERVENTION Echocardiography revealed enlargement of right ventricle (right ventricle [RV]: 43 mm). Electrophysiological examination showed the origin of VAs is next to a small low-voltage zone of RV. Radiofrequency delivery at the origin successfully terminated VAs without occurrence of complication. OUTCOME The patient was free from arrhythmias and got an improvement of exercise tolerance, just with mild dyspnea when climbing stairs World Health Organization Class II (WHO class II), during six-month follow up. LESSONS This case suggests the low-voltage zone of remodeled RV, which may be secondary to increased pulmonary artery pressure, serves as the substrate for VAs initiation in patient with PH. Radiofrequency ablation can successfully terminate VAs and the termination of VAs can significantly improve the patient's impaired exercise tolerance.
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Affiliation(s)
- Song Zou
- Department of Cardiology, West China Hospital
| | - Zhifu Cen
- Department of Cardiology, West China Hospital
| | - Ruikun Jia
- Department of Cardiology, West China Hospital
| | - Sijie Lu
- Department of Cardiology, West China Hospital
| | - Yan Hao
- State Key Laboratory of Biotherapy, Sichuan University, Chengdu, Sichuan, People's Republic of China
| | - Kaijun Cui
- Department of Cardiology, West China Hospital
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12
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Tian L, Wu D, Dasgupta A, Chen KH, Mewburn J, Potus F, Lima PDA, Hong Z, Zhao YY, Hindmarch CCT, Kutty S, Provencher S, Bonnet S, Sutendra G, Archer SL. Epigenetic Metabolic Reprogramming of Right Ventricular Fibroblasts in Pulmonary Arterial Hypertension: A Pyruvate Dehydrogenase Kinase-Dependent Shift in Mitochondrial Metabolism Promotes Right Ventricular Fibrosis. Circ Res 2020; 126:1723-1745. [PMID: 32216531 DOI: 10.1161/circresaha.120.316443] [Citation(s) in RCA: 73] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
RATIONALE Right ventricular (RV) fibrosis in pulmonary arterial hypertension contributes to RV failure. While RV fibrosis reflects changes in the function of resident RV fibroblasts (RVfib), these cells are understudied. OBJECTIVE Examine the role of mitochondrial metabolism of RVfib in RV fibrosis in human and experimental pulmonary arterial hypertension. METHODS AND RESULTS Male Sprague-Dawley rats received monocrotaline (MCT; 60 mg/kg) or saline. Drinking water containing no supplement or the PDK (pyruvate dehydrogenase kinase) inhibitor dichloroacetate was started 7 days post-MCT. At week 4, treadmill testing, echocardiography, and right heart catheterization were performed. The effects of PDK activation on mitochondrial dynamics and metabolism, RVfib proliferation, and collagen production were studied in RVfib in cell culture. Epigenetic mechanisms for persistence of the profibrotic RVfib phenotype in culture were evaluated. PDK expression was also studied in the RVfib of patients with decompensated RV failure (n=11) versus control (n=7). MCT rats developed pulmonary arterial hypertension, RV fibrosis, and RV failure. MCT-RVfib (but not left ventricular fibroblasts) displayed excess mitochondrial fission and had increased expression of PDK isoforms 1 and 3 that persisted for >5 passages in culture. PDK-mediated decreases in pyruvate dehydrogenase activity and oxygen consumption rate were reversed by dichloroacetate (in RVfib and in vivo) or siRNA targeting PDK 1 and 3 (in RVfib). These interventions restored mitochondrial superoxide and hydrogen peroxide production and inactivated HIF (hypoxia-inducible factor)-1α, which was pathologically activated in normoxic MCT-RVfib. Redox-mediated HIF-1α inactivation also decreased the expression of TGF-β1 (transforming growth factor-beta-1) and CTGF (connective tissue growth factor), reduced fibroblast proliferation, and decreased collagen production. HIF-1α activation in MCT-RVfib reflected increased DNMT (DNA methyltransferase) 1 expression, which was associated with a decrease in its regulatory microRNA, miR-148b-3p. In MCT rats, dichloroacetate, at therapeutic levels in the RV, reduced phospho-pyruvate dehydrogenase expression, RV fibrosis, and hypertrophy and improved RV function. In patients with pulmonary arterial hypertension and RV failure, RVfib had increased PDK1 expression. CONCLUSIONS MCT-RVfib manifest a DNMT1-HIF-1α-PDK-mediated, chamber-specific, metabolic memory that promotes collagen production and RV fibrosis. This epigenetic mitochondrial-metabolic pathway is a potential antifibrotic therapeutic target.
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Affiliation(s)
- Lian Tian
- From the Department of Medicine (L.T., D.W., A.D., K.-H.C., J.M., F.P., S.L.A.), Queen's University, Kingston, Ontario, Canada
| | - Danchen Wu
- From the Department of Medicine (L.T., D.W., A.D., K.-H.C., J.M., F.P., S.L.A.), Queen's University, Kingston, Ontario, Canada
| | - Asish Dasgupta
- From the Department of Medicine (L.T., D.W., A.D., K.-H.C., J.M., F.P., S.L.A.), Queen's University, Kingston, Ontario, Canada
| | - Kuang-Hueih Chen
- From the Department of Medicine (L.T., D.W., A.D., K.-H.C., J.M., F.P., S.L.A.), Queen's University, Kingston, Ontario, Canada
| | - Jeffrey Mewburn
- From the Department of Medicine (L.T., D.W., A.D., K.-H.C., J.M., F.P., S.L.A.), Queen's University, Kingston, Ontario, Canada
| | - Francois Potus
- From the Department of Medicine (L.T., D.W., A.D., K.-H.C., J.M., F.P., S.L.A.), Queen's University, Kingston, Ontario, Canada
| | - Patricia D A Lima
- Queen'ps CardioPulmonary Unit, Department of Medicine, Translational Institute of Medicine (P.D.A.L., C.C.T.H., S.L.A.), Queen's University, Kingston, Ontario, Canada
| | - Zhigang Hong
- Department of Pharmacology, University of Illinois at Chicago (Z.H.)
| | - Yuan-Yuan Zhao
- Department of Agricultural, Food and Nutritional Science (Y.-Y.Z.), University of Alberta, Edmonton, Canada
| | - Charles C T Hindmarch
- Queen'ps CardioPulmonary Unit, Department of Medicine, Translational Institute of Medicine (P.D.A.L., C.C.T.H., S.L.A.), Queen's University, Kingston, Ontario, Canada
| | - Shelby Kutty
- Department of Medicine, John Hopkins University, Baltimore, MD (S.K.)
| | - Steeve Provencher
- Pulmonary Hypertension Research Group, Department of Medicine, Heart and Lung Institute of Quebec, Laval University, Canada (S.P., S.B.)
| | - Sebastien Bonnet
- Pulmonary Hypertension Research Group, Department of Medicine, Heart and Lung Institute of Quebec, Laval University, Canada (S.P., S.B.)
| | - Gopinath Sutendra
- Department of Medicine (G.S.), University of Alberta, Edmonton, Canada
| | - Stephen L Archer
- From the Department of Medicine (L.T., D.W., A.D., K.-H.C., J.M., F.P., S.L.A.), Queen's University, Kingston, Ontario, Canada.,Queen'ps CardioPulmonary Unit, Department of Medicine, Translational Institute of Medicine (P.D.A.L., C.C.T.H., S.L.A.), Queen's University, Kingston, Ontario, Canada
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13
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Gururaja Rao S, Patel NJ, Singh H. Intracellular Chloride Channels: Novel Biomarkers in Diseases. Front Physiol 2020; 11:96. [PMID: 32116799 PMCID: PMC7034325 DOI: 10.3389/fphys.2020.00096] [Citation(s) in RCA: 65] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Accepted: 01/27/2020] [Indexed: 12/27/2022] Open
Abstract
Ion channels are integral membrane proteins present on the plasma membrane as well as intracellular membranes. In the human genome, there are more than 400 known genes encoding ion channel proteins. Ion channels are known to regulate several cellular, organellar, and physiological processes. Any mutation or disruption in their function can result in pathological disorders, both common or rare. Ion channels present on the plasma membrane are widely acknowledged for their role in various biological processes, but in recent years, several studies have pointed out the importance of ion channels located in intracellular organelles. However, ion channels located in intracellular organelles are not well-understood in the context of physiological conditions, such as the generation of cellular excitability and ionic homeostasis. Due to the lack of information regarding their molecular identity and technical limitations of studying them, intracellular organelle ion channels have thus far been overlooked as potential therapeutic targets. In this review, we focus on a novel class of intracellular organelle ion channels, Chloride Intracellular Ion Channels (CLICs), mainly documented for their role in cardiovascular, neurophysiology, and tumor biology. CLICs have a single transmembrane domain, and in cells, they exist in cytosolic as well as membranous forms. They are predominantly present in intracellular organelles and have recently been shown to be localized to cardiomyocyte mitochondria as well as exosomes. In fact, a member of this family, CLIC5, is the first mitochondrial chloride channel to be identified on the molecular level in the inner mitochondrial membrane, while another member, CLIC4, is located predominantly in the outer mitochondrial membrane. In this review, we discuss this unique class of intracellular chloride channels, their role in pathologies, such as cardiovascular, cancer, and neurodegenerative diseases, and the recent developments concerning their usage as theraputic targets.
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Affiliation(s)
- Shubha Gururaja Rao
- Department of Physiology and Cell Biology, The Ohio State University Wexner Medical Center, Columbus, OH, United States
| | - Neel J Patel
- Department of Cardiology, Hospital of the University of Pennsylvania, Philadelphia, PA, United States
| | - Harpreet Singh
- Department of Physiology and Cell Biology, The Ohio State University Wexner Medical Center, Columbus, OH, United States
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14
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Response of non-failing hypertrophic rat hearts to prostaglandin F2α. Curr Res Physiol 2019; 2:1-11. [PMID: 34746811 PMCID: PMC8562143 DOI: 10.1016/j.crphys.2019.12.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Revised: 12/04/2019] [Accepted: 12/16/2019] [Indexed: 11/21/2022] Open
Abstract
Background Prostaglandin F2α (PGF2α) has a positively inotropic effect on right ventricular (RV) trabeculae from healthy adult rat hearts, and may therefore be therapeutically useful as a non-catecholaminergic inotrope. These provide additional contractile support for the heart without the added energetic demand of increased heart rate, and are also suitable for patients with reduced β adrenergic receptor (β-AR) responsiveness, or impaired mitochondrial energy supply. However, the response of hypertrophied rat hearts to PGF2α has not previously been examined. Our aim was therefore to determine the effect of PGF2α on isolated perfused rat hearts with RV hypertrophy following induction of pulmonary artery hypertension. Methods Male Wistar rats (300 g) were injected with either 60 mg kg−1 of monocrotaline (MCT, n = 10) or sterile saline as control (CON, n = 11). Four weeks post injection; hearts were isolated and Langendorff-perfused in sinus rhythm. Measurement of left ventricular (LV) pressure and the electrocardiogram were made and the response to 0.3 μM PGF2α was determined. Results PGF2α increased LV developed pressure in CON and in 60% MCT hearts, with no change in heart rate. However, 40% of MCT hearts developed arrhythmias during the peak inotropic response. For comparison, the response to 0.03 μM isoproterenol (ISO) was also investigated. Peak LV pressure developed sooner in response to ISO compared to PGF2α in both rat groups, although the inotropic response to ISO was reduced in MCT hearts. Analysis of fixed ventricular tissue confirmed that only RV myocytes were hypertrophied in MCT hearts. Our study showed that PGF2α was positively inotropic for healthy hearts, but found it generated arrhythmias in 40% of MCT hearts at the dose investigated. However, a more physiological dose of PGF2α may be a useful alternative without the added energetic cost of catecholaminergic inotropes. PGF2α elicits a positive inotropic response in isolated, perfused healthy and hypertrophic rat hearts, with no chronotropic effects, unlike β-AR stimulation. The dose of 0.3 μM PGF2α investigated also triggered sustained, slow onset, arrhythmic activity in 40% of hypertrophic MCT hearts. The peak inotropic response to PGF2α is slower to establish in comparison to the characteristic response to β-AR stimulation, which suggests PGF2α acts via a separate signalling pathway within cardiomyocytes. Hypertrophic MCT hearts had a reduced inotropic response to β-AR stimulation, which illustrates the importance of developing non-catecholaminergic inotropes which will eliminate the increased energetic cost and improve myocardial performance.
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15
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Le T, Makar C, Morway P, Hoftman N, Umar S. Pulmonary artery denervation: a novel treatment modality for pulmonary hypertension. J Thorac Dis 2019; 11:1094-1096. [PMID: 31179049 DOI: 10.21037/jtd.2019.02.93] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Trixie Le
- Department of Anesthesiology and Perioperative Medicine, Division of Molecular Medicine, David Geffen School of Medicine, University of California Los Angeles (UCLA), Los Angeles, CA, USA
| | - Christian Makar
- Department of Anesthesiology and Perioperative Medicine, Division of Molecular Medicine, David Geffen School of Medicine, University of California Los Angeles (UCLA), Los Angeles, CA, USA
| | - Philip Morway
- Department of Anesthesiology and Perioperative Medicine, Division of Molecular Medicine, David Geffen School of Medicine, University of California Los Angeles (UCLA), Los Angeles, CA, USA
| | - Nir Hoftman
- Department of Anesthesiology and Perioperative Medicine, Division of Molecular Medicine, David Geffen School of Medicine, University of California Los Angeles (UCLA), Los Angeles, CA, USA
| | - Soban Umar
- Department of Anesthesiology and Perioperative Medicine, Division of Molecular Medicine, David Geffen School of Medicine, University of California Los Angeles (UCLA), Los Angeles, CA, USA
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16
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Cirulis MM, Ryan JJ, Archer SL. Pathophysiology, incidence, management, and consequences of cardiac arrhythmia in pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension. Pulm Circ 2019; 9:2045894019834890. [PMID: 30747032 PMCID: PMC6410395 DOI: 10.1177/2045894019834890] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Arrhythmias are increasingly recognized as serious, end-stage complications of pre-capillary pulmonary hypertension, including pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH). Although arrhythmias contribute to symptoms, morbidity, in-hospital mortality, and possibly sudden death in PAH/CTEPH, there remains a paucity of epidemiologic, pathophysiologic, and outcome data to guide management of these patients. This review summarizes the most current evidence on the topic: from the molecular mechanisms driving arrhythmia in the hypertrophied or failing right heart, to the clinical aspects of epidemiology, diagnosis, and management.
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Affiliation(s)
- Meghan M Cirulis
- 1 Division of Pulmonary Medicine, Department of Medicine, University of Utah, Salt Lake City, UT, USA
- 2 Division of Cardiovascular Medicine, Department of Medicine, University of Utah, Salt Lake City, UT, USA
| | - John J Ryan
- 2 Division of Cardiovascular Medicine, Department of Medicine, University of Utah, Salt Lake City, UT, USA
| | - Stephen L Archer
- 3 Department of Medicine, Queen's University, Kingston, ON, Canada
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17
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Strauss B, Sassi Y, Bueno-Beti C, Ilkan Z, Raad N, Cacheux M, Bisserier M, Turnbull IC, Kohlbrenner E, Hajjar RJ, Hadri L, Akar FG. Intra-tracheal gene delivery of aerosolized SERCA2a to the lung suppresses ventricular arrhythmias in a model of pulmonary arterial hypertension. J Mol Cell Cardiol 2018; 127:20-30. [PMID: 30502350 DOI: 10.1016/j.yjmcc.2018.11.017] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 11/21/2018] [Accepted: 11/24/2018] [Indexed: 11/19/2022]
Abstract
BACKGROUND Pulmonary arterial hypertension (PAH) results in right ventricular (RV) failure, electro-mechanical dysfunction and heightened risk of sudden cardiac death (SCD), although exact mechanisms and predisposing factors remain unclear. Because impaired chronotropic response to exercise is a strong predictor of early mortality in patients with PAH, we hypothesized that progressive elevation in heart rate can unmask ventricular tachyarrhythmias (VT) in a rodent model of monocrotaline (MCT)-induced PAH. We further hypothesized that intra-tracheal gene delivery of aerosolized AAV1.SERCA2a (AAV1.S2a), an approach which improves pulmonary vascular remodeling in PAH, can suppress VT in this model. OBJECTIVE To determine the efficacy of pulmonary AAV1.S2a in reversing electrophysiological (EP) remodeling and suppressing VT in PAH. METHODS Male rats received subcutaneous injection of MCT (60 mg/kg) leading to advanced PAH. Three weeks following MCT, rats underwent intra-tracheal delivery of aerosolized AAV1.S2a (MCT + S2a, N = 8) or saline (MCT, N = 9). Age-matched rats served as controls (CTRL, N = 7). The EP substrate and risk of VT were determined using high-resolution optical action potential (AP) mapping ex vivo. The expression levels of key ion channel subunits, fibrosis markers and hypertrophy indices were measured by RT-PCR and histochemical analyses. RESULTS Over 80% of MCT but none of the CTRL hearts were prone to sustained VT by rapid pacing (P < .01). Aerosolized gene delivery of AAV1.S2a to the lung suppressed the incidence of VT to <15% (P < .05). Investigation of the EP substrate revealed marked prolongation of AP duration (APD), increased APD heterogeneity, a reversal in the trans-epicardial APD gradient, and marked conduction slowing in untreated MCT compared to CTRL hearts. These myocardial EP changes coincided with major remodeling in the expression of K and Ca channel subunits, decreased expression of Cx43 and increased expression of pro-fibrotic and pro-hypertrophic markers. Intra-tracheal gene delivery of aerosolized AAV1 carrying S2a but not luciferase resulted in selective upregulation of the human isoform of SERCA2a in the lung but not the heart. This pulmonary intervention, in turn, ameliorated MCT-induced APD prolongation, reversed spatial APD heterogeneity, normalized myocardial conduction, and suppressed the incidence of pacing-induced VT. Comparison of the minimal conduction velocity (CV) generated at the fastest pacing rate before onset of VT or at the end of the protocol revealed significantly lower values in untreated compared to AAV1.S2a treated PAH and CTRL hearts. Reversal of EP remodeling by pulmonary AAV1.S2a gene delivery was accompanied by restored expression of key ion channel transcripts. Restored expression of Cx43 and collagen but not the pore-forming Na channel subunit Nav1.5 likely ameliorated VT by improving CV at rapid rates in PAH. CONCLUSION Aerosolized AAV1.S2a gene delivery selectively to the lungs ameliorates myocardial EP remodeling and VT susceptibility at rapid heart rates. Our findings highlight for the first time the utility of a non-cardiac gene therapy approach for arrhythmia suppression.
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Affiliation(s)
- Benjamin Strauss
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, NY, New York, USA
| | - Yassine Sassi
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, NY, New York, USA
| | - Carlos Bueno-Beti
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, NY, New York, USA
| | - Zeki Ilkan
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, NY, New York, USA
| | - Nour Raad
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, NY, New York, USA
| | - Marine Cacheux
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, NY, New York, USA
| | - Malik Bisserier
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, NY, New York, USA
| | - Irene C Turnbull
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, NY, New York, USA
| | - Erik Kohlbrenner
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, NY, New York, USA
| | - Roger J Hajjar
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, NY, New York, USA
| | - Lahouaria Hadri
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, NY, New York, USA
| | - Fadi G Akar
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, NY, New York, USA.
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18
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Vélez-Rendón D, Zhang X, Gerringer J, Valdez-Jasso D. Compensated right ventricular function of the onset of pulmonary hypertension in a rat model depends on chamber remodeling and contractile augmentation. Pulm Circ 2018; 8:2045894018800439. [PMID: 30175690 PMCID: PMC6161210 DOI: 10.1177/2045894018800439] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Accepted: 08/22/2018] [Indexed: 11/16/2022] Open
Abstract
Right-ventricular function is a good indicator of pulmonary arterial hypertension (PAH) prognosis; however, how the right ventricle (RV) adapts to the pressure overload is not well understood. Here, we aimed at characterizing the time course of RV early remodeling and discriminate the contribution of ventricular geometric remodeling and intrinsic changes in myocardial mechanical properties in a monocrotaline (MCT) animal model. In a longitudinal study of PAH, ventricular morphology and function were assessed weekly during the first four weeks after MCT exposure. Using invasive measurements of RV pressure and volume, heart performance was evaluated at end of systole and diastole to quantify contractility (end-systolic elastance) and chamber stiffness (end-diastolic elastance). To distinguish between morphological and intrinsic mechanisms, a computational model of the RV was developed and used to determine the level of prediction when accounting for wall masses and unloaded volume measurements changes. By four weeks, mean pulmonary arterial pressure and elastance rose significantly. RV pressures rose significantly after the second week accompanied by significant RV hypertrophy, but RV stroke volume and cardiac output were maintained. The model analysis suggested that, after two weeks, this compensation was only possible due to a significant increase in the intrinsic inotropy of RV myocardium. We conclude that this MCT-PAH rat is a model of RV compensation during the first month after treatment, where geometric remodeling on EDPVR and increased myocardial contractility on ESPVR are the major mechanisms by which stroke volume is preserved in the setting of elevated pulmonary arterial pressure. The mediators of this compensation might themselves promote longer-term adverse remodeling and decompensation in this animal model.
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Affiliation(s)
- Daniela Vélez-Rendón
- Department of Bioengineering, University of Illinois at Chicago, Chicago, IL, USA
| | - Xiaoyan Zhang
- Department of Bioengineering, University of California San Diego, La Jolla, CA, USA
| | - Jesse Gerringer
- Department of Bioengineering, University of Illinois at Chicago, Chicago, IL, USA
- Department of Biomedical Engineering, Marquette University, Milwaukee, WI, USA
| | - Daniela Valdez-Jasso
- Department of Bioengineering, University of Illinois at Chicago, Chicago, IL, USA
- Department of Bioengineering, University of California San Diego, La Jolla, CA, USA
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19
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Frangogiannis NG. Cardiac fibrosis: Cell biological mechanisms, molecular pathways and therapeutic opportunities. Mol Aspects Med 2018; 65:70-99. [PMID: 30056242 DOI: 10.1016/j.mam.2018.07.001] [Citation(s) in RCA: 495] [Impact Index Per Article: 82.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2018] [Accepted: 07/23/2018] [Indexed: 12/13/2022]
Abstract
Cardiac fibrosis is a common pathophysiologic companion of most myocardial diseases, and is associated with systolic and diastolic dysfunction, arrhythmogenesis, and adverse outcome. Because the adult mammalian heart has negligible regenerative capacity, death of a large number of cardiomyocytes results in reparative fibrosis, a process that is critical for preservation of the structural integrity of the infarcted ventricle. On the other hand, pathophysiologic stimuli, such as pressure overload, volume overload, metabolic dysfunction, and aging may cause interstitial and perivascular fibrosis in the absence of infarction. Activated myofibroblasts are the main effector cells in cardiac fibrosis; their expansion following myocardial injury is primarily driven through activation of resident interstitial cell populations. Several other cell types, including cardiomyocytes, endothelial cells, pericytes, macrophages, lymphocytes and mast cells may contribute to the fibrotic process, by producing proteases that participate in matrix metabolism, by secreting fibrogenic mediators and matricellular proteins, or by exerting contact-dependent actions on fibroblast phenotype. The mechanisms of induction of fibrogenic signals are dependent on the type of primary myocardial injury. Activation of neurohumoral pathways stimulates fibroblasts both directly, and through effects on immune cell populations. Cytokines and growth factors, such as Tumor Necrosis Factor-α, Interleukin (IL)-1, IL-10, chemokines, members of the Transforming Growth Factor-β family, IL-11, and Platelet-Derived Growth Factors are secreted in the cardiac interstitium and play distinct roles in activating specific aspects of the fibrotic response. Secreted fibrogenic mediators and matricellular proteins bind to cell surface receptors in fibroblasts, such as cytokine receptors, integrins, syndecans and CD44, and transduce intracellular signaling cascades that regulate genes involved in synthesis, processing and metabolism of the extracellular matrix. Endogenous pathways involved in negative regulation of fibrosis are critical for cardiac repair and may protect the myocardium from excessive fibrogenic responses. Due to the reparative nature of many forms of cardiac fibrosis, targeting fibrotic remodeling following myocardial injury poses major challenges. Development of effective therapies will require careful dissection of the cell biological mechanisms, study of the functional consequences of fibrotic changes on the myocardium, and identification of heart failure patient subsets with overactive fibrotic responses.
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Affiliation(s)
- Nikolaos G Frangogiannis
- The Wilf Family Cardiovascular Research Institute, Department of Medicine (Cardiology), Albert Einstein College of Medicine, 1300 Morris Park Avenue, Forchheimer G46B, Bronx, NY, 10461, USA.
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20
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Fowler ED, Drinkhill MJ, Norman R, Pervolaraki E, Stones R, Steer E, Benoist D, Steele DS, Calaghan SC, White E. Beta1-adrenoceptor antagonist, metoprolol attenuates cardiac myocyte Ca 2+ handling dysfunction in rats with pulmonary artery hypertension. J Mol Cell Cardiol 2018; 120:74-83. [PMID: 29807024 PMCID: PMC6013283 DOI: 10.1016/j.yjmcc.2018.05.015] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Accepted: 05/22/2018] [Indexed: 01/13/2023]
Abstract
Right heart failure is the major cause of death in Pulmonary Artery Hypertension (PAH) patients but is not a current, specific therapeutic target. Pre-clinical studies have shown that adrenoceptor blockade can improve cardiac function but the mechanisms of action within right ventricular (RV) myocytes are unknown. We tested whether the β1-adrenoceptor blocker metoprolol could improve RV myocyte function in an animal model of PAH, by attenuating adverse excitation-contraction coupling remodeling. PAH with RV failure was induced in rats by monocrotaline injection. When PAH was established, animals were given 10 mg/kg/day metoprolol (MCT + BB) or vehicle (MCT). The median time to the onset of heart failure signs was delayed from 23 days (MCT), to 31 days (MCT + BB). At 23 ± 1 days post-injection, MCT + BB showed improved in vivo cardiac function, measured by echocardiography. RV hypertrophy was reduced despite persistent elevated afterload. RV myocyte contractility during field stimulation was improved at higher pacing frequencies in MCT + BB. Preserved t-tubule structure, more uniform evoked Ca2+ release, increased SERCA2a expression and faster ventricular repolarization (measured in vivo by telemetry) may account for the improved contractile function. Sarcoplasmic reticulum Ca2+ overload was prevented in MCT + BB myocytes resulting in fewer spontaneous Ca2+ waves, with a lower pro-arrhythmic potential. Our novel finding of attenuation of defects in excitation contraction coupling by β1-adrenoceptor blockade with delays in the onset of HF, identifies the RV as a promising therapeutic target in PAH. Moreover, our data suggest existing therapies for left ventricular failure may also be beneficial in PAH induced RV failure.
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Affiliation(s)
- Ewan D Fowler
- Multidisciplinary Cardiovascular Research Centre, University of Leeds, Leeds, UK; School of Physiology, Pharmacology and Neuroscience, Faculty of Biomedical Sciences, University of Bristol, Bristol, UK
| | - Mark J Drinkhill
- Multidisciplinary Cardiovascular Research Centre, University of Leeds, Leeds, UK
| | - Ruth Norman
- Multidisciplinary Cardiovascular Research Centre, University of Leeds, Leeds, UK
| | | | - Rachel Stones
- Multidisciplinary Cardiovascular Research Centre, University of Leeds, Leeds, UK
| | - Emma Steer
- Multidisciplinary Cardiovascular Research Centre, University of Leeds, Leeds, UK
| | - David Benoist
- Multidisciplinary Cardiovascular Research Centre, University of Leeds, Leeds, UK; L'institut de rythmologie et modélisation cardiaque, Inserm U-1045, Université de Bordeaux, Bordeaux, France
| | - Derek S Steele
- Multidisciplinary Cardiovascular Research Centre, University of Leeds, Leeds, UK
| | - Sarah C Calaghan
- Multidisciplinary Cardiovascular Research Centre, University of Leeds, Leeds, UK
| | - Ed White
- Multidisciplinary Cardiovascular Research Centre, University of Leeds, Leeds, UK.
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21
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Hardy MEL, Pervolaraki E, Bernus O, White E. Dynamic Action Potential Restitution Contributes to Mechanical Restitution in Right Ventricular Myocytes From Pulmonary Hypertensive Rats. Front Physiol 2018; 9:205. [PMID: 29593564 PMCID: PMC5859380 DOI: 10.3389/fphys.2018.00205] [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] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Accepted: 02/23/2018] [Indexed: 11/21/2022] Open
Abstract
We investigated the steepened dynamic action potential duration (APD) restitution of rats with pulmonary artery hypertension (PAH) and right ventricular (RV) failure and tested whether the observed APD restitution properties were responsible for negative mechanical restitution in these myocytes. PAH and RV failure were provoked in male Wistar rats by a single injection of monocrotaline (MCT) and compared with saline-injected animals (CON). Action potentials were recorded from isolated RV myocytes at stimulation frequencies between 1 and 9 Hz. Action potential waveforms recorded at 1 Hz were used as voltage clamp profiles (action potential clamp) at stimulation frequencies between 1 and 7 Hz to evoke rate-dependent currents. Voltage clamp profiles mimicking typical CON and MCT APD restitution were applied and cell shortening simultaneously monitored. Compared with CON myocytes, MCT myocytes were hypertrophied; had less polarized diastolic membrane potentials; had action potentials that were triggered by decreased positive current density and shortened by decreased negative current density; APD was longer and APD restitution steeper. APD90 restitution was unchanged by exposure to the late Na+-channel blocker (5 μM) ranolazine or the intracellular Ca2+ buffer BAPTA. Under AP clamp, stimulation frequency-dependent inward currents were smaller in MCT myocytes and were abolished by BAPTA. In MCT myocytes, increasing stimulation frequency decreased contraction amplitude when depolarization duration was shortened, to mimic APD restitution, but not when depolarization duration was maintained. We present new evidence that the membrane potential of PAH myocytes is less stable than normal myocytes, being more easily perturbed by external currents. These observations can explain increased susceptibility to arrhythmias. We also present novel evidence that negative APD restitution is at least in part responsible for the negative mechanical restitution in PAH myocytes. Thus, our study links electrical restitution remodeling to a defining mechanical characteristic of heart failure, the reduced ability to respond to an increase in demand.
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Affiliation(s)
- Matthew E L Hardy
- Multidisciplinary Cardiovascular Research Centre, University of Leeds, Leeds, United Kingdom
| | - Eleftheria Pervolaraki
- Multidisciplinary Cardiovascular Research Centre, University of Leeds, Leeds, United Kingdom
| | - Olivier Bernus
- Multidisciplinary Cardiovascular Research Centre, University of Leeds, Leeds, United Kingdom.,IHU Liryc, L'institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France.,Centre de Recherche Cardio-Thoracique de Bordeaux, Université de Bordeaux, U1045, Bordeaux, France.,Centre de Recherche Cardio-Thoracique de Bordeaux, Institut National de la Santé et de la Recherche Médicale, U1045, Bordeaux, France
| | - Ed White
- Multidisciplinary Cardiovascular Research Centre, University of Leeds, Leeds, United Kingdom
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22
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Pham T, Nisbet L, Taberner A, Loiselle D, Han JC. Pulmonary arterial hypertension reduces energy efficiency of right, but not left, rat ventricular trabeculae. J Physiol 2018; 596:1153-1166. [PMID: 29363144 DOI: 10.1113/jp275578] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Accepted: 01/17/2018] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS Pulmonary arterial hypertension (PAH) triggers right ventricle (RV) hypertrophy and left ventricle (LV) atrophy, which progressively leads to heart failure. We designed experiments under conditions mimicking those encountered by the heart in vivo that allowed us to investigate whether consequent structural and functional remodelling of the ventricles affects their respective energy efficiencies. We found that peak work output was lower in RV trabeculae from PAH rats due to reduced extent and velocity of shortening. However, their suprabasal enthalpy was unaffected due to increased activation heat, resulting in reduced suprabasal efficiency. There was no effect of PAH on LV suprabasal efficiency. We conclude that the mechanism underlying the reduced energy efficiency of hypertrophied RV tissues is attributable to the increased energy cost of Ca2+ cycling, whereas atrophied LV tissues still maintain normal mechano-energetic performance. ABSTRACT Pulmonary arterial hypertension (PAH) greatly increases the afterload on the right ventricle (RV), triggering RV hypertrophy, which progressively leads to RV failure. In contrast, the disease reduces the passive filling pressure of the left ventricle (LV), resulting in LV atrophy. We investigated whether these distinct structural and functional consequences to the ventricles affect their respective energy efficiencies. We studied trabeculae isolated from both ventricles of Wistar rats with monocrotaline-induced PAH and their respective Control groups. Trabeculae were mounted in a calorimeter at 37°C. While contracting at 5 Hz, they were subjected to stress-length work-loops over a wide range of afterloads. They were subsequently required to undergo a series of isometric contractions at various muscle lengths. In both protocols, stress production, length change and suprabasal heat output were simultaneously measured. We found that RV trabeculae from PAH rats generated higher activation heat, but developed normal active stress. Their peak external work output was lower due to reduced extent and velocity of shortening. Despite lower peak work output, suprabasal enthalpy was unaffected, thereby rendering suprabasal efficiency lower. Crossbridge efficiency, however, was unaffected. In contrast, LV trabeculae from PAH rats maintained normal mechano-energetic performance. Pulmonary arterial hypertension reduces the suprabasal energy efficiency of hypertrophied right ventricular tissues as a consequence of the increased energy cost of Ca2+ cycling.
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Affiliation(s)
- Toan Pham
- Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand.,Department of Physiology, The University of Auckland, Auckland, New Zealand
| | - Linley Nisbet
- Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand.,Department of Physiology, The University of Auckland, Auckland, New Zealand
| | - Andrew Taberner
- Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand.,Department of Engineering Science, The University of Auckland, Auckland, New Zealand
| | - Denis Loiselle
- Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand.,Department of Physiology, The University of Auckland, Auckland, New Zealand
| | - June-Chiew Han
- Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand
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23
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Vaillancourt M, Chia P, Sarji S, Nguyen J, Hoftman N, Ruffenach G, Eghbali M, Mahajan A, Umar S. Autonomic nervous system involvement in pulmonary arterial hypertension. Respir Res 2017; 18:201. [PMID: 29202826 PMCID: PMC5715548 DOI: 10.1186/s12931-017-0679-6] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Accepted: 11/13/2017] [Indexed: 01/28/2023] Open
Abstract
Pulmonary arterial hypertension (PAH) is a chronic pulmonary vascular disease characterized by increased pulmonary vascular resistance (PVR) leading to right ventricular (RV) failure. Autonomic nervous system involvement in the pathogenesis of PAH has been demonstrated several years ago, however the extent of this involvement is not fully understood. PAH is associated with increased sympathetic nervous system (SNS) activation, decreased heart rate variability, and presence of cardiac arrhythmias. There is also evidence for increased renin-angiotensin-aldosterone system (RAAS) activation in PAH patients associated with clinical worsening. Reduction of neurohormonal activation could be an effective therapeutic strategy for PAH. Although therapies targeting adrenergic receptors or RAAS signaling pathways have been shown to reverse cardiac remodeling and improve outcomes in experimental pulmonary hypertension (PH)-models, the effectiveness and safety of such treatments in clinical settings have been uncertain. Recently, novel direct methods such as cervical ganglion block, pulmonary artery denervation (PADN), and renal denervation have been employed to attenuate SNS activation in PAH. In this review, we intend to summarize the multiple aspects of autonomic nervous system involvement in PAH and overview the different pharmacological and invasive strategies used to target autonomic nervous system for the treatment of PAH.
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Affiliation(s)
- Mylène Vaillancourt
- Department of Anesthesiology and Perioperative Medicine, Division of Molecular Medicine, David Geffen School of Medicine, University of California Los Angeles (UCLA), Los Angeles, CA, BH 520A CHS, USA
| | - Pamela Chia
- Department of Anesthesiology and Perioperative Medicine, Division of Molecular Medicine, David Geffen School of Medicine, University of California Los Angeles (UCLA), Los Angeles, CA, BH 520A CHS, USA
| | - Shervin Sarji
- Department of Anesthesiology and Perioperative Medicine, Division of Molecular Medicine, David Geffen School of Medicine, University of California Los Angeles (UCLA), Los Angeles, CA, BH 520A CHS, USA
| | - Jason Nguyen
- Department of Anesthesiology and Perioperative Medicine, Division of Molecular Medicine, David Geffen School of Medicine, University of California Los Angeles (UCLA), Los Angeles, CA, BH 520A CHS, USA
| | - Nir Hoftman
- Department of Anesthesiology and Perioperative Medicine, Division of Molecular Medicine, David Geffen School of Medicine, University of California Los Angeles (UCLA), Los Angeles, CA, BH 520A CHS, USA
| | - Gregoire Ruffenach
- Department of Anesthesiology and Perioperative Medicine, Division of Molecular Medicine, David Geffen School of Medicine, University of California Los Angeles (UCLA), Los Angeles, CA, BH 520A CHS, USA
| | - Mansoureh Eghbali
- Department of Anesthesiology and Perioperative Medicine, Division of Molecular Medicine, David Geffen School of Medicine, University of California Los Angeles (UCLA), Los Angeles, CA, BH 520A CHS, USA
| | - Aman Mahajan
- Department of Anesthesiology and Perioperative Medicine, Division of Molecular Medicine, David Geffen School of Medicine, University of California Los Angeles (UCLA), Los Angeles, CA, BH 520A CHS, USA
| | - Soban Umar
- Department of Anesthesiology and Perioperative Medicine, Division of Molecular Medicine, David Geffen School of Medicine, University of California Los Angeles (UCLA), Los Angeles, CA, BH 520A CHS, USA.
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24
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Neto-Neves EM, Frump AL, Vayl A, Kline JA, Lahm T. Isolated heart model demonstrates evidence of contractile and diastolic dysfunction in right ventricles from rats with sugen/hypoxia-induced pulmonary hypertension. Physiol Rep 2017; 5:5/19/e13438. [PMID: 29038355 PMCID: PMC5641930 DOI: 10.14814/phy2.13438] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Revised: 07/31/2017] [Accepted: 08/16/2017] [Indexed: 01/29/2023] Open
Abstract
Although extensively used for the study of left ventricular function, limited experience exists with the isolated heart model in the evaluation of right ventricular (RV) function. In particular, no published experience exists with this tool in sugen/hypoxia‐induced pulmonary hypertension (SuHx‐PH), a frequently used model of severe and progressive PH. We sought to characterize markers of RV contractile and diastolic function in SuHx‐PH and to establish their relationship with markers of maladaptive RV remodeling. Hearts were excised from anesthetized Sprague Dawley rats with or without SuHx‐PH and perfused via the aorta using a Langendorff preparation. We explored the Frank–Starling relationship of RV function (RV developed pressure, dP/dtmax, and dP/dtmin; all normalized to RV mass) by increasing RV end‐diastolic pressure (RVEDP) from 0 to 40 mmHg. Functional studies were complemented by quantification of RV pro‐apoptotic signaling (bcl2/bax), procontractile signaling (apelin), and stress response signaling (p38MAPK activation). Pearson's correlation analysis was performed for functional and biochemical parameters. SuHx‐RVs exhibited severe RV dysfunction with marked hypertrophy and decreased echocardiographic cardiac output. For any given RVEDP, SuHx‐RVs demonstrated less developed pressure and lower dP/dtmax, as well as less pronounced dP/dtmin, suggestive of decreased contractile and diastolic function. SuHx‐RVs exhibited decreased bcl2/bax ratios, apelin expression, and p38MAPK activation. Bcl2/bax and apelin RNA abundance correlated positively with RV developed pressure and dP/dtmax and negatively with dP/dtmin. p38MAPK activation correlated positively with RV developed pressure. We conclude that SuHx‐RVs exhibit severe contractile and diastolic dysfunction. Increased pro‐apoptotic signaling and attenuated procontractile and stress response signaling may contribute to these functional alterations.
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Affiliation(s)
- Evandro M Neto-Neves
- Department of Emergency Medicine, Indiana University School of Medicine, Indianapolis, Indiana
| | - Andrea L Frump
- Department of Medicine, Division of Pulmonary, Critical Care, Occupational and Sleep Medicine, Indiana University School of Medicine, Indianapolis, Indiana
| | - Alexandra Vayl
- Department of Medicine, Division of Pulmonary, Critical Care, Occupational and Sleep Medicine, Indiana University School of Medicine, Indianapolis, Indiana
| | - Jeffrey A Kline
- Department of Emergency Medicine, Indiana University School of Medicine, Indianapolis, Indiana.,Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, Indiana
| | - Tim Lahm
- Department of Medicine, Division of Pulmonary, Critical Care, Occupational and Sleep Medicine, Indiana University School of Medicine, Indianapolis, Indiana .,Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, Indiana.,Richard L. Roudebush Veterans Affairs Medical Center, Indianapolis, Indiana
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25
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Protective effects of aloperine on monocrotaline-induced pulmonary hypertension in rats. Biomed Pharmacother 2017; 89:632-641. [DOI: 10.1016/j.biopha.2017.02.033] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2016] [Revised: 02/05/2017] [Accepted: 02/10/2017] [Indexed: 01/10/2023] Open
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26
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Maarman GJ, Schulz R, Sliwa K, Schermuly RT, Lecour S. Novel putative pharmacological therapies to protect the right ventricle in pulmonary hypertension: a review of current literature. Br J Pharmacol 2017; 174:497-511. [PMID: 28099680 DOI: 10.1111/bph.13721] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Revised: 09/06/2016] [Accepted: 09/27/2016] [Indexed: 12/15/2022] Open
Abstract
Pulmonary hypertension (PH) is defined by elevated mean pulmonary artery pressure following the pathological remodelling of small pulmonary arteries. An increase in right ventricular (RV) afterload results in RV hypertrophy and RV failure. The pathophysiology of PH, and RV remodelling in particular, is not well understood, thus explaining, at least in part, why current PH therapies have a limited effect. Existing therapies mostly target the pulmonary circulation. Because the remodelled RV fails to support normal cardiac function, patients eventually succumb from RV failure. Developing novel therapies that directly target the function of the RV may therefore benefit patients with PH. In the past decade, several promising studies have investigated novel cardioprotective strategies in experimental models of PH. This review aims to comprehensively discuss and highlight these novel experimental approaches to confer, in the long-term, greater health benefit in patients with PH.
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Affiliation(s)
- Gerald J Maarman
- Hatter Institute for Cardiovascular Research in Africa (HICRA) and MRC Inter-University Cape Heart Group, Department of Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Rainer Schulz
- Institute of Physiology, Justus Liebig University Giessen, Giessen, Germany
| | - Karen Sliwa
- Hatter Institute for Cardiovascular Research in Africa (HICRA) and MRC Inter-University Cape Heart Group, Department of Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Ralph Theo Schermuly
- Universities of Giessen and Marburg Lung Centre, Member of the German Lung Centre (DZL), Justus Liebig University Giessen, Giessen, Germany
| | - Sandrine Lecour
- Hatter Institute for Cardiovascular Research in Africa (HICRA) and MRC Inter-University Cape Heart Group, Department of Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
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Prognostic Relevance of Nonsustained Ventricular Tachycardia in Patients with Pulmonary Hypertension. BIOMED RESEARCH INTERNATIONAL 2016; 2016:1327265. [PMID: 28090536 PMCID: PMC5206408 DOI: 10.1155/2016/1327265] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/18/2016] [Accepted: 11/23/2016] [Indexed: 12/15/2022]
Abstract
Background. Increased pulmonary vascular resistance in patients with pulmonary hypertension (PH) leads to an increased afterload of right heart and cardiac remodeling which could provide the substrate or trigger for arrhythmias. Supraventricular arrhythmias were associated with clinical deterioration but were not associated with sudden cardiac death (SCD). SCD has been reported to account for approximately 30% of deaths in patients with pulmonary arterial hypertension (PAH). Objective. The role of nonsustained ventricular tachycardia (nsVT) and its prognostic relevance in patients with PH remains unclear. This study evaluated the prognostic relevance of nsVT in patients with PAH and chronic thromboembolic pulmonary hypertension (CTEPH). Methods. Retrospectively, patients with PAH and CTEPH who underwent Holter ECG monitoring and available data of survival were investigated. Results. Seventy-eight (PAH: 55, CTEPH: 23) patients were evaluated. Holter ECG revealed nsVT in 12 patients. Twenty-one patients died during follow-up. In patients with nsVT, tricuspid annular plane systolic excursion was lower (p = 0.001), and systolic pulmonary arterial pressure was higher (p = 0.163). Mean survival of patients without/with nsVT was 155.2 ± 8.5/146.4 ± 21.4 months (p = 0.690). The association between arrhythmias and survival was not confounded by age (p = 0.681), gender (p = 0.752), 6-MW distance (p = 0.196), or arterial hypertension (p = 0.238). Conclusions. In patients with PH, nsVT occurs more often than previously reported, and patients with PH group 1 seem to be more at risk.
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Kohut A, Patel N, Singh H. Comprehensive Echocardiographic Assessment of the Right Ventricle in Murine Models. J Cardiovasc Ultrasound 2016; 24:229-238. [PMID: 27721954 PMCID: PMC5050312 DOI: 10.4250/jcu.2016.24.3.229] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Revised: 08/03/2016] [Accepted: 08/03/2016] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Non-invasive high-resolution echocardiography to evaluate cardiovascular function of small animals is increasingly being used due to availability of genetically engineered murine models. Even though guidelines and standard values for humans were revised by the American Society of Echocardiography, evaluations on murine models are not performed according to any standard protocols. These limitations are preventing translation of preclinical evaluations to clinical meaningful conclusions. We have assessed the right heart of two commonly used murine models according to standard clinical guidelines, and provided the practical guide and sample values for cardiac assessments. METHODS Right heart echocardiography evaluations of CD1 and C57BL/6 mice were performed under 1-3% isoflurane anesthesia using Vevo® 2100 Imaging System with a high-frequency (18-38 MHz) probe (VisualSonics MS400). We have provided a practical guide on how to image and assess the right heart of a mouse which is frequently used to evaluate development of right heart failure due to pulmonary hypertension. RESULTS Our results show significant differences between CD1 and C57BL/6 mice. Right ventricle structural assessment showed significantly larger (p < 0.05) size, and pulmonary artery diameter in CD1 mice (n = 11) compared to C57BL/6 mice (n = 15). Right heart systolic and diastolic functions were similar for both strains. CONCLUSION Our practical guide on how to image and assess the right heart of murine models provides the first comprehensive values which can be used for preclinical research studies using echocardiography. Additionally, our results indicate that there is a high variability between mouse species and experimental models should be carefully selected for cardiac evaluations.
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Affiliation(s)
- Andrew Kohut
- Division of Cardiology, Drexel University College of Medicine, Philadelphia, PA, USA.; Department of Medicine, Drexel University College of Medicine, Philadelphia, PA, USA
| | - Nishi Patel
- Department of Medicine, Drexel University College of Medicine, Philadelphia, PA, USA
| | - Harpreet Singh
- Division of Cardiology, Drexel University College of Medicine, Philadelphia, PA, USA.; Department of Medicine, Drexel University College of Medicine, Philadelphia, PA, USA.; Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, PA, USA
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Borgdorff MAJ, Dickinson MG, Berger RMF, Bartelds B. Right ventricular failure due to chronic pressure load: What have we learned in animal models since the NIH working group statement? Heart Fail Rev 2016; 20:475-91. [PMID: 25771982 PMCID: PMC4463984 DOI: 10.1007/s10741-015-9479-6] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Right ventricular (RV) failure determines outcome in patients with pulmonary hypertension, congenital heart diseases and in left ventricular failure. In 2006, the Working Group on Cellular and Molecular Mechanisms of Right Heart Failure of the NIH advocated the development of preclinical models to study the pathophysiology and pathobiology of RV failure. In this review, we summarize the progress of research into the pathobiology of RV failure and potential therapeutic interventions. The picture emerging from this research is that RV adaptation to increased afterload is characterized by increased contractility, dilatation and hypertrophy. Clinical RV failure is associated with progressive diastolic deterioration and disturbed ventricular–arterial coupling in the presence of increased contractility. The pathobiology of the failing RV shows similarities with that of the LV and is marked by lack of adequate increase in capillary density leading to a hypoxic environment and oxidative stress and a metabolic switch from fatty acids to glucose utilization. However, RV failure also has characteristic features. So far, therapies aiming to specifically improve RV function have had limited success. The use of beta blockers and sildenafil may hold promise, but new therapies have to be developed. The use of recently developed animal models will aid in further understanding of the pathobiology of RV failure and development of new therapeutic strategies.
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Affiliation(s)
- Marinus A J Borgdorff
- Department of Pediatrics, Center for Congenital Heart Diseases, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands,
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Te ALD, Chung FP, Lin YJ, Chen SA. Irregular wide QRS complex tachycardia in a patient with pulmonary hypertension: What is the mechanism? HeartRhythm Case Rep 2015; 2:63-66. [PMID: 28491634 PMCID: PMC5412644 DOI: 10.1016/j.hrcr.2015.10.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/30/2022] Open
Affiliation(s)
- Abigail Louise D Te
- Division of Cardiology Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Fa-Po Chung
- Division of Cardiology Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.,Department of Medicine National Yang-Ming University School of Medicine, Taipei, Taiwan
| | - Yenn-Jiang Lin
- Division of Cardiology Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.,Department of Medicine National Yang-Ming University School of Medicine, Taipei, Taiwan
| | - Shih-Ann Chen
- Division of Cardiology Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.,Department of Medicine National Yang-Ming University School of Medicine, Taipei, Taiwan
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Bandorski D, Erkapic D, Stempfl J, Höltgen R, Grünig E, Schmitt J, Chasan R, Grimminger J, Neumann T, Hamm CW, Seeger W, Ghofrani HA, Gall H. Ventricular tachycardias in patients with pulmonary hypertension: an underestimated prevalence? A prospective clinical study. Herzschrittmacherther Elektrophysiol 2015; 26:155-162. [PMID: 26031512 DOI: 10.1007/s00399-015-0364-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Accepted: 03/10/2015] [Indexed: 06/04/2023]
Abstract
BACKGROUND Sudden cardiac death (SCD) accounts for approximately 30 % in patients with pulmonary arterial hypertension (PAH). The exact circumference for SCD in this patient population is still unclear. Malignant cardiac arrhythmias are reported to be rarely present. There are no systematic data concerning long-term electrocardiographic (ECG) recording in patients with PAH. OBJECTIVES We sought to investigate the rate of potentially relevant arrhythmias in patients with pulmonary hypertension (PH). METHODS Consecutive patients without diagnosis of known cardiac arrhythmias followed in our outpatient clinic for PH were enrolled in the study. All patients underwent a 72-h Holter ECG. Clinical data, 6-min walk distance, laboratory values, and echocardiography were collected/performed. RESULTS Ninety-two consecutive patients (New York Heart Association class (NYHA) III/IV: 65.2 %/5.4 %, PH Group 1: 35.9 %, Group 3: 10.9 %, Group 4: 28.3 %, Group 5: 2.2 %) were investigated. Relevant arrhythmias were newly detected in 17 patients: non-sustained ventricular tachycardia (n = 12), intermittent second-degree heart block (n = 1), intermittent third-degree heart block (n= 3), and atrial flutter (n = 1). Echocardiographic systolic pulmonary pressure and diameter of the right heart were elevated in patients with relevant arrhythmias. Right heart catheterization revealed higher pulmonary vascular resistance (672 vs. 542 dyn · s · cm(-5), p = 0.247) and lower cardiac index (2.46 vs. 2.82 l/min/m(2), p = 0.184). CONCLUSIONS Ventricular tachycardias occur more often in PH patients than previously reported. However, the prognostic relevance of non-sustained ventricular tachycardias in this cohort remains unclear. As a large number of PH patients die from SCD, closer monitoring, e.g., using implantable event recorders, might be useful to identify patients at high risk.
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Affiliation(s)
- Dirk Bandorski
- University of Giessen and Marburg Lung Center (UGMLC), Giessen, Germany,
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van der Laarse A, Cobbaert CM, Umar S. Stem and progenitor cell therapy for pulmonary arterial hypertension: effects on the right ventricle (2013 Grover Conference Series). Pulm Circ 2015; 5:73-80. [PMID: 25992272 DOI: 10.1086/679701] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Accepted: 08/25/2014] [Indexed: 12/12/2022] Open
Abstract
In experimental animals and in patients with pulmonary arterial hypertension (PAH), a wide spectrum of structural and functional conditions is known that may be responsible for the switch of a state of "compensated" right ventricular (RV) hypertrophy to a state of RV failure. In recent years, therapy with differentiated cells, endothelial progenitor cells, and mesenchymal stem cells has been shown to cause partial or complete reversal of pathological characteristics of PAH. The therapeutic effects of stem or progenitor cell therapy are considered to be (1) paracrine effects from stem or progenitor cells that had engrafted in the myocardium (or elsewhere), by compounds that have anti-inflammatory, antiapoptotic, and proangiogenic actions and (2) unloading effects on the right ventricle due to stem or progenitor cell-induced decrease in pulmonary vascular resistance and decrease in pulmonary artery pressure.
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Affiliation(s)
- Arnoud van der Laarse
- Department of Cardiology, Leiden University Medical Center, Leiden, the Netherlands ; Department of Clinical Chemistry and Laboratory Medicine, Leiden University Medical Center, Leiden, the Netherlands
| | - Christa M Cobbaert
- Department of Clinical Chemistry and Laboratory Medicine, Leiden University Medical Center, Leiden, the Netherlands
| | - Soban Umar
- Department of Anesthesiology, Division of Molecular Medicine, David Geffen School of Medicine at University of California, Los Angeles, California, USA
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Transmural dispersion of repolarization and cardiac remodeling in ventricles of rabbit with right ventricular hypertrophy. J Pharmacol Toxicol Methods 2014; 71:129-36. [PMID: 25305588 DOI: 10.1016/j.vascn.2014.09.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Revised: 09/26/2014] [Accepted: 09/30/2014] [Indexed: 11/23/2022]
Abstract
INTRODUCTION Recent publications demonstrated that rabbits with right ventricular hypertrophy (RVH) possess high sensitivity and specificity for drug-induced arrhythmias. However, the underlying mechanism has not been elucidated. This study aimed to evaluate RVH induced changes in cardiac remodeling especially the transmural dispersion of repolarization (TDR), epicardial monophasic action potentials (MAP), and hERG mRNA expression in rabbits. METHODS New Zealand White rabbits (n=13) were divided into 2 groups: sham operated (SHAM, n=6) and pulmonary artery banding (PAB, n=7). PAB was induced by narrowing the pulmonary artery. Twenty weeks after surgery, hemodynamic, cardiac function, electrocardiograms, and MAP were obtained from PAB compared with SHAM. After measurement, rabbits were sacrificed to collect ventricular myocardium for histopathological analysis and measurement of hERG mRNA expression by real time PCR. RESULTS After 20weeks, the % HW to BW ratio of whole heart and right ventricle (RV) and left and right ventricular free wall thickness was significantly increased in PAB when compared with those in SHAM. PAB has a significant electrical remodeling as demonstrated by lengthening of QT, QTc intervals, and increased Tp-Te duration. PAB also has a significant functional remodeling verified by decreased contractility index of RV and lengthened time constant of relaxation of LV. MAP of RV epicardium was significantly shortened in PAB consistently with increased hERG mRNA expression at the epicardium of RV. DISCUSSION The rabbit with PAB demonstrates cardiac remodeling diastolic and systolic dysfunctions. These rabbits also demonstrate increased TDR and electrical remodeling related to the change of hERG mRNA expression which may be prone to develop arrhythmias.
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Temple IP, Monfredi O, Quigley G, Schneider H, Zi M, Cartwright EJ, Boyett MR, Mahadevan VS, Hart G. Macitentan treatment retards the progression of established pulmonary arterial hypertension in an animal model. Int J Cardiol 2014; 177:423-8. [PMID: 25305681 PMCID: PMC4251701 DOI: 10.1016/j.ijcard.2014.09.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Revised: 08/23/2014] [Accepted: 09/15/2014] [Indexed: 12/14/2022]
Abstract
BACKGROUND Macitentan is a new endothelin receptor antagonist that is used to treat pulmonary arterial hypertension in humans. Treatment of established pulmonary hypertension with macitentan was studied using the monocrotaline model of pulmonary hypertension. METHODS Three groups of rats were created (n=12): control (CON: macitentan only), monocrotaline (MCT: monocrotaline only) and macitentan (MACI: macitentan and monocrotaline). Monocrotaline (60 mg/kg) was injected in the MCT and MACI groups on day 0; volume matched saline was injected in the CON groups. Macitentan therapy (30 mg/kg/day) was commenced on day 11 in the CON and MACI groups. Serial echocardiography and ECGs were performed. The rats were sacrificed if they showed clinical deterioration. RESULTS The MCT and MACI rats showed signs of pulmonary hypertension by day 7 (maximum pulmonary velocity, CON 1.15 ± 0.15m/s vs MCT 1.04 ± 0.10 m/s vs MACI 0.99 ± 0.18 m/s; p<0.05). Both the MCT and MACI groups developed pulmonary hypertension, but this was less severe in the MACI group (day 21 pulmonary artery acceleration time, MCT 17.55 ± 1.56 ms vs MACI 22.55 ± 1.00 ms; pulmonary artery deceleration, MCT 34.72 ± 3.72 m/s(2) vs MACI 17.30 ± 1.89 m/s(2); p<0.05). Right ventricular hypertrophy and QT interval increases were more pronounced in MCT than MACI (right ventricle wall thickness, MCT 0.13 ± 0.1cm vs MACI 0.10 ± 0.1cm; QT interval, MCT 85 ± 13 ms vs MACI 71 ± 14 ms; p<0.05). Survival benefit was not seen in the MACI group (p=0.50). CONCLUSIONS Macitentan treatment improves haemodynamic parameters in established pulmonary hypertension. Further research is required to see if earlier introduction of macitentan has greater effects.
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Affiliation(s)
- I P Temple
- Institute of Cardiovascular Sciences, University of Manchester, UK.
| | - O Monfredi
- Institute of Cardiovascular Sciences, University of Manchester, UK
| | - G Quigley
- Institute of Cardiovascular Sciences, University of Manchester, UK
| | - H Schneider
- Institute of Cardiovascular Sciences, University of Manchester, UK
| | - M Zi
- Institute of Cardiovascular Sciences, University of Manchester, UK
| | - E J Cartwright
- Institute of Cardiovascular Sciences, University of Manchester, UK
| | - M R Boyett
- Institute of Cardiovascular Sciences, University of Manchester, UK
| | - V S Mahadevan
- Central Manchester University Hospitals NHS Trust, UK
| | - G Hart
- Institute of Cardiovascular Sciences, University of Manchester, UK
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Electrophysiological studies in patients with pulmonary hypertension: a retrospective investigation. BIOMED RESEARCH INTERNATIONAL 2014; 2014:617565. [PMID: 24977152 PMCID: PMC4058223 DOI: 10.1155/2014/617565] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Revised: 04/23/2014] [Accepted: 05/01/2014] [Indexed: 11/24/2022]
Abstract
Few studies have investigated patients with pulmonary hypertension and arrhythmias. Data on electrophysiological studies in these patients are rare. In a retrospective dual-centre design, we analysed data from patients with indications for electrophysiological study. Fifty-five patients with pulmonary hypertension were included (Dana Point Classification: group 1: 14, group 2: 23, group 3: 4, group 4: 8, group 5: 2, and 4 patients with exercised-induced pulmonary hypertension).
Clinical data, 6-minute walk distance, laboratory values, and echocardiography were collected/performed. Nonsustained ventricular tachycardia was the most frequent indication (n = 15) for an electrophysiological study, followed by atrial flutter (n = 14). In summary 36 ablations were performed and 25 of them were successful (atrial flutter 12 of 14 and atrioventricular nodal reentrant tachycardia 4 of 4). Fluoroscopy time was 16 ± 14.4 minutes. Electrophysiological studies in patients with pulmonary hypertension are feasible and safe. Ablation procedures are as effective in these patients as in non-PAH patients with atrial flutter and atrioventricular nodal reentrant tachycardia and should be performed likewise. The prognostic relevance of ventricular stimulations and inducible ventricular tachycardias in these patients is still unclear and requires further investigation.
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Coronel R, Wilders R, Verkerk AO, Wiegerinck RF, Benoist D, Bernus O. Electrophysiological changes in heart failure and their implications for arrhythmogenesis. Biochim Biophys Acta Mol Basis Dis 2013; 1832:2432-41. [DOI: 10.1016/j.bbadis.2013.04.002] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2012] [Accepted: 04/01/2013] [Indexed: 01/07/2023]
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Snipelisky D, Burger C, Shapiro B, Kusumoto F. Electrocardiographic Changes in Patients Responding to Treatment with Group I Pulmonary Arterial Hypertension. South Med J 2013; 106:618-23. [DOI: 10.1097/smj.0000000000000021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Tanaka Y, Takase B, Yao T, Ishihara M. Right Ventricular Electrical Remodeling and Arrhythmogenic Substrate in Rat Pulmonary Hypertension. Am J Respir Cell Mol Biol 2013; 49:426-36. [DOI: 10.1165/rcmb.2012-0089oc] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Ypey DL, van Meerwijk WPM, Umar S, Pijnappels DA, Schalij MJ, van der Laarse A. Depolarization-induced automaticity in rat ventricular cardiomyocytes is based on the gating properties of L-type calcium and slow Kv channels. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2012; 42:241-55. [PMID: 23089919 DOI: 10.1007/s00249-012-0866-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2011] [Revised: 09/28/2012] [Accepted: 10/04/2012] [Indexed: 10/27/2022]
Abstract
Depolarization-induced automaticity (DIA) of cardiomyocytes is the property of those cells to generate pacemaker cell-like spontaneous electrical activity when subjected to a depolarizing current. This property provides a candidate mechanism for generation of pathogenic ectopy in cardiac tissue. The purpose of this study was to determine the biophysical mechanism of DIA in terms of the ion conductance properties of the cardiomyocyte membrane. First, we determined, by use of the conventional whole-cell patch-clamp technique, the membrane conductance and DIA properties of ventricular cardiomyocytes isolated from adult rat heart. Second, we reproduced and analysed DIA properties by using an adapted version of the experimentally based mathematical cardiomyocyte model of Pandit et al. (Biophys J 81:3029-3051 2001, Biophys J 84:832-841 2003) and Padmala and Demir (J Cardiovasc Electrophysiol 14:990-995 2003). DIA in 23 rat cardiomyocytes was a damped membrane potential oscillation with a variable number of action potentials and/or waves, depending on the strength of the depolarizing current and the particular cell. The adapted model was used to reconstruct the DIA properties of a particular cardiomyocyte from its whole-cell voltage-clamp currents. The main currents involved in DIA were an L-type calcium current (I CaL) and a slowly activating and inactivating Kv current (I ss), with linear (I B) and inward rectifier (I K1) currents acting as background currents and I Na and I t as modulators. Essential for DIA is a sufficiently large window current of a slowly inactivating I CaL combined with a critically sized repolarizing current I ss. Slow inactivation of I ss makes DIA transient. In conclusion, we established a membrane mechanism of DIA primarily based on I CaL, I ss and inward rectifier properties; this may be helpful in understanding cardiac ectopy and its treatment.
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Affiliation(s)
- Dirk L Ypey
- Department of Cardiology, Leiden University Medical Center, PO Box 9600, 2300 RC Leiden, The Netherlands
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Umar S, Nadadur R, Iorga A, Amjedi M, Matori H, Eghbali M. Cardiac structural and hemodynamic changes associated with physiological heart hypertrophy of pregnancy are reversed postpartum. J Appl Physiol (1985) 2012; 113:1253-9. [PMID: 22923507 DOI: 10.1152/japplphysiol.00549.2012] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Pregnancy is associated with ventricular hypertrophy and volume overload. Here we investigated whether late pregnancy is associated with cardiac structural and hemodynamic changes, and if these changes are reversed postpartum. Female mice (C57BL/6) were used in nonpregnant diestrus (NP), late-pregnant (LP), or 7-day postpartum (PP7) stages. Echocardiography and cardiac catheterization were performed to monitor cardiac hemodynamics. Transcript expression of proangiogenic vascular endothelial growth factor, cardiac fetal gene osteopontin, cardiac extracellular matrix-degrading enzymes matrix metalloproteinase-2, and a disintegrin and metalloproteinase-15 and -17 were assessed by RT-PCR. Masson trichrome staining for cardiac fibrosis and endothelial marker CD31 immunostaining for angiogenesis were performed. Heart hypertrophy in LP was fully reversed in PP7 (heart weight: NP = 114 ± 4 mg; LP = 147 ± 2 mg; PP7 = 117 ± 8 mg, P < 0.05 for LP vs. PP7). LP had elevated left ventricular (LV) pressure (119 ± 5 mmHg in LP vs. 92 ± 7 mmHg in NP, P < 0.05) that was restored at PP7 (95 ± 8 mmHg, P < 0.001 vs. LP). LP had increased LV contractility (maximal rate of increase of LV pressure = 6,664 ± 297 mmHg/s in LP vs. 4,294 ± 568 mmHg/s in NP, P < 0.01) that was restored at PP7 (5,313 ± 636 mmHg/s, P < 0.05 vs. LP). LV ejection fraction was reduced in LP (LP = 58 ± 1% vs. NP = 70 ± 4%, P < 0.001) and was already restored at PP1 (77 ± 2%, P < 0.001 vs. LP). Myocardial angiogenesis was significantly increased in LP (capillary density = 1.25 ± 0.02 vs. 0.95 ± 0.01 capillaries/myocyte in NP, P < 0.001) and was fully restored in PP7 (0.98 ± 0.01, P < 0.001 vs. LP). Vascular endothelial growth factor was upregulated in LP (LP = 1.4 ± 0.1 vs. NP = 1 ± 0.1, normalized to NP, P < 0.001) and was restored in PP7 (PP7 = 0.83 ± 0.1, P < 0.001 vs. LP). There was no increase in cardiac fibrosis in LP. Matrix metalloproteinase-2 transcript levels were downregulated in LP (LP = 0.47 ± 0.03 vs. NP = 1 ± 0.01, normalized to NP, P < 0.001) and was restored at PP7 (0.70 ± 0.1, P < 0.001 vs. LP). In conclusion, pregnancy-induced heart hypertrophy is associated with transient cardiac dysfunction, increased cardiac angiogenesis, lack of fibrosis, and decreased expression of remodeling enzymes that are reversed postpartum.
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Affiliation(s)
- Soban Umar
- Department of Anesthesiology, Division of Molecular Medicine David Geffen School of Medicine at University of California-Los Angeles, CA 90095, USA
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Benoist D, Stones R, Drinkhill MJ, Benson AP, Yang Z, Cassan C, Gilbert SH, Saint DA, Cazorla O, Steele DS, Bernus O, White E. Cardiac arrhythmia mechanisms in rats with heart failure induced by pulmonary hypertension. Am J Physiol Heart Circ Physiol 2012; 302:H2381-95. [PMID: 22427523 PMCID: PMC3378302 DOI: 10.1152/ajpheart.01084.2011] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2011] [Accepted: 03/15/2012] [Indexed: 12/22/2022]
Abstract
Pulmonary hypertension provokes right heart failure and arrhythmias. Better understanding of the mechanisms underlying these arrhythmias is needed to facilitate new therapeutic approaches for the hypertensive, failing right ventricle (RV). The aim of our study was to identify the mechanisms generating arrhythmias in a model of RV failure induced by pulmonary hypertension. Rats were injected with monocrotaline to induce either RV hypertrophy or failure or with saline (control). ECGs were measured in conscious, unrestrained animals by telemetry. In isolated hearts, electrical activity was measured by optical mapping and myofiber orientation by diffusion tensor-MRI. Sarcoplasmic reticular Ca(2+) handling was studied in single myocytes. Compared with control animals, the T-wave of the ECG was prolonged and in three of seven heart failure animals, prominent T-wave alternans occurred. Discordant action potential (AP) alternans occurred in isolated failing hearts and Ca(2+) transient alternans in failing myocytes. In failing hearts, AP duration and dispersion were increased; conduction velocity and AP restitution were steeper. The latter was intrinsic to failing single myocytes. Failing hearts had greater fiber angle disarray; this correlated with AP duration. Failing myocytes had reduced sarco(endo)plasmic reticular Ca(2+)-ATPase activity, increased sarcoplasmic reticular Ca(2+)-release fraction, and increased Ca(2+) spark leak. In hypertrophied hearts and myocytes, dysfunctional adaptation had begun, but alternans did not develop. We conclude that increased electrical and structural heterogeneity and dysfunctional sarcoplasmic reticular Ca(2+) handling increased the probability of alternans, a proarrhythmic predictor of sudden cardiac death. These mechanisms are potential therapeutic targets for the correction of arrhythmias in hypertensive, failing RVs.
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Affiliation(s)
- David Benoist
- Institute of Membrane and Systems Biology, University of Leeds, United Kingdom
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