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Gök C, Fuller W. Rise of palmitoylation: A new trick to tune NCX1 activity. Biochim Biophys Acta Mol Cell Res 2024; 1871:119719. [PMID: 38574822 DOI: 10.1016/j.bbamcr.2024.119719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 03/11/2024] [Accepted: 03/27/2024] [Indexed: 04/06/2024]
Abstract
The cardiac Na+/Ca2+ Exchanger (NCX1) controls transmembrane calcium flux in numerous tissues. The only reversible post-translational modification established to regulate NCX1 is palmitoylation, which alters the ability of the exchanger to inactivate. Palmitoylation creates a binding site for the endogenous XIP domain, a region of the NCX1 intracellular loop established to inactivate NCX1. The binding site created by NCX1 palmitoylation sensitizes the transporter to XIP. Herein we summarize our recent knowledge on NCX1 palmitoylation and its association with cardiac pathologies, and discuss these findings in the light of the recent cryo-EM structures of human NCX1.
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Affiliation(s)
- Caglar Gök
- School of Cardiovascular and Metabolic Health (SCMH), Sir James Black Building, University of Glasgow, Glasgow G12 8QQ, United Kingdom.
| | - William Fuller
- School of Cardiovascular and Metabolic Health (SCMH), Sir James Black Building, University of Glasgow, Glasgow G12 8QQ, United Kingdom
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2
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Wijnker PJM, Dinani R, van der Laan NC, Algül S, Knollmann BC, Verkerk AO, Remme CA, Zuurbier CJ, Kuster DWD, van der Velden J. Hypertrophic cardiomyopathy dysfunction mimicked in human engineered heart tissue and improved by sodium-glucose cotransporter 2 inhibitors. Cardiovasc Res 2024; 120:301-317. [PMID: 38240646 PMCID: PMC10939456 DOI: 10.1093/cvr/cvae004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 11/15/2023] [Accepted: 11/29/2023] [Indexed: 03/16/2024] Open
Abstract
AIMS Hypertrophic cardiomyopathy (HCM) is the most common inherited cardiomyopathy, often caused by pathogenic sarcomere mutations. Early characteristics of HCM are diastolic dysfunction and hypercontractility. Treatment to prevent mutation-induced cardiac dysfunction is lacking. Sodium-glucose cotransporter 2 inhibitors (SGLT2i) are a group of antidiabetic drugs that recently showed beneficial cardiovascular outcomes in patients with acquired forms of heart failure. We here studied if SGLT2i represent a potential therapy to correct cardiomyocyte dysfunction induced by an HCM sarcomere mutation. METHODS AND RESULTS Contractility was measured of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) harbouring an HCM mutation cultured in 2D and in 3D engineered heart tissue (EHT). Mutations in the gene encoding β-myosin heavy chain (MYH7-R403Q) or cardiac troponin T (TNNT2-R92Q) were investigated. In 2D, intracellular [Ca2+], action potential and ion currents were determined. HCM mutations in hiPSC-CMs impaired relaxation or increased force, mimicking early features observed in human HCM. SGLT2i enhance the relaxation of hiPSC-CMs, to a larger extent in HCM compared to control hiPSC-CMs. Moreover, SGLT2i-effects on relaxation in R403Q EHT increased with culture duration, i.e. hiPSC-CMs maturation. Canagliflozin's effects on relaxation were more pronounced than empagliflozin and dapagliflozin. SGLT2i acutely altered Ca2+ handling in HCM hiPSC-CMs. Analyses of SGLT2i-mediated mechanisms that may underlie enhanced relaxation in mutant hiPSC-CMs excluded SGLT2, Na+/H+ exchanger, peak and late Nav1.5 currents, and L-type Ca2+ current, but indicate an important role for the Na+/Ca2+ exchanger. Indeed, electrophysiological measurements in mutant hiPSC-CM indicate that SGLT2i altered Na+/Ca2+ exchange current. CONCLUSION SGLT2i (canagliflozin > dapagliflozin > empagliflozin) acutely enhance relaxation in human EHT, especially in HCM and upon prolonged culture. SGLT2i may represent a potential therapy to correct early cardiac dysfunction in HCM.
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Affiliation(s)
- Paul J M Wijnker
- Department of Physiology, Amsterdam UMC, Vrije Universiteit Amsterdam, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands
- Amsterdam Cardiovascular Sciences, Heart Failure & Arrhythmias, De Boelelaan 1108, 1081 HZ Amsterdam, The Netherlands
| | - Rafeeh Dinani
- Department of Physiology, Amsterdam UMC, Vrije Universiteit Amsterdam, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands
- Amsterdam Cardiovascular Sciences, Heart Failure & Arrhythmias, De Boelelaan 1108, 1081 HZ Amsterdam, The Netherlands
| | - Nico C van der Laan
- Department of Physiology, Amsterdam UMC, Vrije Universiteit Amsterdam, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands
- Amsterdam Cardiovascular Sciences, Heart Failure & Arrhythmias, De Boelelaan 1108, 1081 HZ Amsterdam, The Netherlands
| | - Sila Algül
- Department of Physiology, Amsterdam UMC, Vrije Universiteit Amsterdam, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands
- Amsterdam Cardiovascular Sciences, Heart Failure & Arrhythmias, De Boelelaan 1108, 1081 HZ Amsterdam, The Netherlands
| | - Bjorn C Knollmann
- Vanderbilt Center for Arrhythmia Research and Therapeutics, Division of Clinical Pharmacology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Arie O Verkerk
- Amsterdam Cardiovascular Sciences, Heart Failure & Arrhythmias, De Boelelaan 1108, 1081 HZ Amsterdam, The Netherlands
- Experimental Cardiology, Amsterdam UMC, Academic Medical Centre, Amsterdam, The Netherlands
| | - Carol Ann Remme
- Amsterdam Cardiovascular Sciences, Heart Failure & Arrhythmias, De Boelelaan 1108, 1081 HZ Amsterdam, The Netherlands
- Experimental Cardiology, Amsterdam UMC, Academic Medical Centre, Amsterdam, The Netherlands
| | - Coert J Zuurbier
- Amsterdam Cardiovascular Sciences, Heart Failure & Arrhythmias, De Boelelaan 1108, 1081 HZ Amsterdam, The Netherlands
- Laboratory for Experimental Intensive Care and Anesthesiology (L.E.I.C.A.), Department of Anesthesiology, Amsterdam UMC, Academic Medical Centre, Amsterdam, The Netherlands
| | - Diederik W D Kuster
- Department of Physiology, Amsterdam UMC, Vrije Universiteit Amsterdam, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands
- Amsterdam Cardiovascular Sciences, Heart Failure & Arrhythmias, De Boelelaan 1108, 1081 HZ Amsterdam, The Netherlands
| | - Jolanda van der Velden
- Department of Physiology, Amsterdam UMC, Vrije Universiteit Amsterdam, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands
- Amsterdam Cardiovascular Sciences, Heart Failure & Arrhythmias, De Boelelaan 1108, 1081 HZ Amsterdam, The Netherlands
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3
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Herting JR, König JH, Hadova K, Heinick A, Müller FU, Pauls P, Seidl MD, Soppa C, Kirchhefer U. Hypercontractile cardiac phenotype in mice overexpressing the regulatory subunit PR72 of protein phosphatase 2A. Front Cardiovasc Med 2023; 10:1239555. [PMID: 37868783 PMCID: PMC10590119 DOI: 10.3389/fcvm.2023.1239555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Accepted: 09/22/2023] [Indexed: 10/24/2023] Open
Abstract
Background The activity, localization, and substrate specificity of the protein phosphatase 2A (PP2A) heterotrimer are controlled by various regulatory B subunits. PR72 belongs to the B'' gene family and has been shown to be upregulated in human heart failure. However, little is known about the functions of PR72 in the myocardium. Methods To address this issue, we generated a transgenic mouse model with heart-specific overexpression of PP2A-PR72. Biochemical and physiological methods were used to determine contractility, Ca2+ cycling parameters, and protein phosphorylation. Results A 2.5-fold increase in PR72 expression resulted in moderate cardiac hypertrophy. Maximal ventricular pressure was increased in catheterized transgenic mice (TG) compared to wild-type (WT) littermates. This was accompanied by an increased shortening of sarcomere length and faster relaxation at the single-cell level in TG. In parallel with these findings, the peak amplitude of Ca2+ transients was increased, and the decay in intracellular Ca2+ levels was shortened in TG compared to WT. The changes in Ca2+ cycling in TG were also evident from an increase in the full duration and width at half maximum of Ca2+ sparks. Consistent with the contractile data, phosphorylation of phospholamban at threonine-17 was higher in TG hearts. The lower expression of the Na+/Ca2+ exchanger may also contribute to the hypercontractile state in transgenic myocardium. Conclusion Our results suggest that PP2A-PR72 plays an important role in regulating cardiac contractile function and Ca2+ cycling, indicating that the upregulation of PR72 in heart failure is an attempt to compensate functionally.
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Affiliation(s)
- Julius R. Herting
- Institut für Pharmakologie und Toxikologie, Universitätsklinikum Münster, Universität Münster, Münster, Germany
| | - Jule H. König
- Institut für Pharmakologie und Toxikologie, Universitätsklinikum Münster, Universität Münster, Münster, Germany
| | - Katarina Hadova
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Comenius University in Bratislava, Bratislava, Slovakia
| | - Alexander Heinick
- Institut für Pharmakologie und Toxikologie, Universitätsklinikum Münster, Universität Münster, Münster, Germany
| | - Frank U. Müller
- Institut für Pharmakologie und Toxikologie, Universitätsklinikum Münster, Universität Münster, Münster, Germany
| | - Paul Pauls
- Institut für Pharmakologie und Toxikologie, Universitätsklinikum Münster, Universität Münster, Münster, Germany
| | - Matthias D. Seidl
- Institut für Pharmakologie und Toxikologie, Universitätsklinikum Münster, Universität Münster, Münster, Germany
| | - Carolina Soppa
- Institut für Pharmakologie und Toxikologie, Universitätsklinikum Münster, Universität Münster, Münster, Germany
| | - Uwe Kirchhefer
- Institut für Pharmakologie und Toxikologie, Universitätsklinikum Münster, Universität Münster, Münster, Germany
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4
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Lin R, Peng X, Li Y, Wang X, Liu X, Jia X, Zhang C, Liu N, Dong J. Empagliflozin attenuates doxorubicin-impaired cardiac contractility by suppressing reactive oxygen species in isolated myocytes. Mol Cell Biochem 2023:10.1007/s11010-023-04830-z. [PMID: 37648958 DOI: 10.1007/s11010-023-04830-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2023] [Accepted: 08/14/2023] [Indexed: 09/01/2023]
Abstract
In animal studies, sodium-glucose co-transporter-2 inhibitors-such as empagliflozin-have been shown to improve heart failure and impaired cardiac contractility induced by anthracyclines-including doxorubicin-although the therapeutic mechanism remains unclear. Moreover, abnormalities in Ca2+ handling within ventricular myocytes are the predominant feature of heart failure. Accordingly, this study aimed to investigate whether empagliflozin can alleviate Ca2+ handling disorders induced by acute doxorubicin exposure and elucidate the underlying mechanisms. To this end, ventricular myocytes were isolated from C57BL/6 mice. Contraction function, Ca2+ handling, and mitochondrial reactive oxygen species (ROS) generation were then evaluated using IonOptix or confocal microscopy. Ca2+ handling proteins were detected by western blotting. Results show that incubation with 1 μmol/L of doxorubicin for 120-min impaired cardiac contractility in isolated myocytes, which was significantly alleviated by pretreatment with 1 μmol/L of empagliflozin. Doxorubicin also markedly induced Ca2+ handling disorders, including decreased Ca2+ transients, prolonged Ca2+ transient decay time, enhanced frequency of Ca2+ sparks, and decreased Ca2+ content in the sarcoplasmic reticulum. These dysregulations were improved by pretreatment with empagliflozin. Moreover, empagliflozin effectively inhibited doxorubicin-induced mitochondrial ROS production in isolated myocytes and rescued doxorubicin-induced oxidation of Ca2+/calmodulin-dependent protein kinase II (ox-CaMKII) and CaMKII-dependent phosphorylation of RyR2. Similarly, preincubation with 10 μmol/L Mito-TEMPO mimicked the protective effects of empagliflozin. Collectively, Empagliflozin ameliorated the doxorubicin-induced contraction malfunction and Ca2+-handling disorders. These findings suggest that empagliflozin alleviates Ca2+-handling disorders by improving ROS production in the mitochondria and alleviating the enhanced oxidative CaMKII signaling pathway induced by doxorubicin.
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Affiliation(s)
- Rong Lin
- Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, No 2. Anzhen Road, Chaoyang, 100029, Beijing, China
- North China Medical & Health Group XingTai General Hospital, Xingtai, China
- National Clinical Research Center for Cardiovascular Diseases, Beijing, China
| | - Xiaodong Peng
- Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, No 2. Anzhen Road, Chaoyang, 100029, Beijing, China
- National Clinical Research Center for Cardiovascular Diseases, Beijing, China
| | - Yukun Li
- Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, No 2. Anzhen Road, Chaoyang, 100029, Beijing, China
- National Clinical Research Center for Cardiovascular Diseases, Beijing, China
| | - Xuesi Wang
- Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, No 2. Anzhen Road, Chaoyang, 100029, Beijing, China
- National Clinical Research Center for Cardiovascular Diseases, Beijing, China
| | - Xinmeng Liu
- Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, No 2. Anzhen Road, Chaoyang, 100029, Beijing, China
- National Clinical Research Center for Cardiovascular Diseases, Beijing, China
| | - Xingze Jia
- North China Medical & Health Group XingTai General Hospital, Xingtai, China
| | - Chengjun Zhang
- North China Medical & Health Group XingTai General Hospital, Xingtai, China
| | - Nian Liu
- Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, No 2. Anzhen Road, Chaoyang, 100029, Beijing, China.
- National Clinical Research Center for Cardiovascular Diseases, Beijing, China.
| | - Jianzeng Dong
- Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, No 2. Anzhen Road, Chaoyang, 100029, Beijing, China.
- National Clinical Research Center for Cardiovascular Diseases, Beijing, China.
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5
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Robinson P, Sparrow AJ, Psaras Y, Steeples V, Simon JN, Broyles CN, Chang YF, Brook FA, Wang YJ, Blease A, Zhang X, Abassi YA, Geeves MA, Toepfer CN, Watkins H, Redwood C, Daniels MJ. Comparing the effects of chemical Ca 2+ dyes and R-GECO on contractility and Ca 2+ transients in adult and human iPSC cardiomyocytes. J Mol Cell Cardiol 2023; 180:44-57. [PMID: 37127261 PMCID: PMC10659987 DOI: 10.1016/j.yjmcc.2023.04.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 04/13/2023] [Accepted: 04/28/2023] [Indexed: 05/03/2023]
Abstract
We compared commonly used BAPTA-derived chemical Ca2+ dyes (fura2, Fluo-4, and Rhod-2) with a newer genetically encoded indicator (R-GECO) in single cell models of the heart. We assessed their performance and effects on cardiomyocyte contractility, determining fluorescent signal-to-noise ratios and sarcomere shortening in primary ventricular myocytes from adult mouse and guinea pig, and in human iPSC-derived cardiomyocytes. Chemical Ca2+ dyes displayed dose-dependent contractile impairment in all cell types, and we observed a negative correlation between contraction and fluorescence signal-to-noise ratio, particularly for fura2 and Fluo-4. R-GECO had no effect on sarcomere shortening. BAPTA-based dyes, but not R-GECO, inhibited in vitro acto-myosin ATPase activity. The presence of fura2 accentuated or diminished changes in contractility and Ca2+ handling caused by small molecule modulators of contractility and intracellular ionic homeostasis (mavacamten, levosimendan, and flecainide), but this was not observed when using R-GECO in adult guinea pig left ventricular cardiomyocytes. Ca2+ handling studies are necessary for cardiotoxicity assessments of small molecules intended for clinical use. Caution should be exercised when interpreting small molecule studies assessing contractile effects and Ca2+ transients derived from BAPTA-like chemical Ca2+ dyes in cellular assays, a common platform for cardiac toxicology testing and mechanistic investigation of cardiac disease physiology and treatment.
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Affiliation(s)
- Paul Robinson
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK; BHF Centre of Research Excellence, University of Oxford, Oxford, UK.
| | - Alexander J Sparrow
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK; BHF Centre of Research Excellence, University of Oxford, Oxford, UK
| | - Yiangos Psaras
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK; BHF Centre of Research Excellence, University of Oxford, Oxford, UK
| | - Violetta Steeples
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK; BHF Centre of Research Excellence, University of Oxford, Oxford, UK
| | - Jillian N Simon
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK; BHF Centre of Research Excellence, University of Oxford, Oxford, UK
| | - Connor N Broyles
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK; BHF Centre of Research Excellence, University of Oxford, Oxford, UK
| | - Yu-Fen Chang
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK; BHF Centre of Research Excellence, University of Oxford, Oxford, UK
| | - Frances A Brook
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK; BHF Centre of Research Excellence, University of Oxford, Oxford, UK
| | - Ying-Jie Wang
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK; BHF Centre of Research Excellence, University of Oxford, Oxford, UK
| | - Andrew Blease
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK; BHF Centre of Research Excellence, University of Oxford, Oxford, UK
| | - Xiaoyu Zhang
- Agilent Biosciences, Inc., San Diego, CA 92121, USA
| | | | | | - Christopher N Toepfer
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK; BHF Centre of Research Excellence, University of Oxford, Oxford, UK; Department of Genetics, Harvard Medical School, Boston, MA, USA
| | - Hugh Watkins
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK; BHF Centre of Research Excellence, University of Oxford, Oxford, UK; Department of Cardiology, Oxford University NHS Hospitals Trust, Oxford, UK
| | - Charles Redwood
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK; BHF Centre of Research Excellence, University of Oxford, Oxford, UK
| | - Matthew J Daniels
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK; BHF Centre of Research Excellence, University of Oxford, Oxford, UK; Department of Cardiology, Oxford University NHS Hospitals Trust, Oxford, UK; Department of Cardiovascular Sciences, University of Manchester, Manchester, UK.
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6
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Kadosaka T, Watanabe M, Natsui H, Koizumi T, Nakao M, Koya T, Hagiwara H, Kamada R, Temma T, Karube F, Fujiyama F, Anzai T. Empagliflozin attenuates arrhythmogenesis in diabetic cardiomyopathy by normalizing intracellular Ca 2+ handling in ventricular cardiomyocytes. Am J Physiol Heart Circ Physiol 2023; 324:H341-H354. [PMID: 36607794 DOI: 10.1152/ajpheart.00391.2022] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Diabetic cardiomyopathy has been reported to increase the risk of fatal ventricular arrhythmia. The beneficial effects of the selective sodium-glucose cotransporter-2 inhibitor have not been fully examined in the context of antiarrhythmic therapy, especially its direct cardioprotective effects despite the negligible SGLT2 expression in cardiomyocytes. We aimed to examine the antiarrhythmic effects of empagliflozin (EMPA) treatment on diabetic cardiomyocytes, with a special focus on Ca2+ handling. We conducted echocardiography and hemodynamic studies and studied electrophysiology, Ca2+ handling, and protein expression in C57BLKS/J-leprdb/db mice (db/db mice) and their nondiabetic lean heterozygous Leprdb/+ littermates (db/+ mice). Preserved systolic function with diastolic dysfunction was observed in 16-wk-old db/db mice. During arrhythmia induction, db/db mice had significantly increased premature ventricular complexes (PVCs) than controls, which was attenuated by EMPA. In protein expression analyses, calmodulin-dependent protein kinase II (CaMKII) Thr287 autophosphorylation and CaMKII-dependent RyR2 phosphorylation (S2814) were significantly increased in diabetic hearts, which were inhibited by EMPA. In addition, global O-GlcNAcylation significantly decreased with EMPA treatment. Furthermore, EMPA significantly inhibited ventricular cardiomyocyte glucose uptake. Diabetic cardiomyocytes exhibited increased spontaneous Ca2+ events and decreased sarcoplasmic reticulum (SR) Ca2+ content, along with impaired Ca2+ transient, all of which normalized with EMPA treatment. Notably, most EMPA-induced improvements in Ca2+ handling were abolished by the addition of an O-GlcNAcase (OGA) inhibitor. In conclusion, EMPA attenuated ventricular arrhythmia inducibility by normalizing the intracellular Ca2+ handling, and we speculated that this effect was, at least partly, due to the inhibition of O-GlcNAcylation via the suppression of glucose uptake into cardiomyocytes.NEW & NOTEWORTHY SGLT2is are known to improve cardiovascular outcomes regardless of the presence of diabetes and decrease traditional cardiovascular risk factors. We demonstrated, for the first time, that EMPA inhibited PVCs by normalizing Ca2+ handling in diabetic mice. Our data suggest that the effects of SGLT2is on calcium handling may occur because of suppression of O-GlcNAcylation through inhibition of glucose uptake and not because of NHE inhibition, as previously suggested.
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Affiliation(s)
- Takahide Kadosaka
- Department of Cardiovascular Medicine, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan
| | - Masaya Watanabe
- Department of Cardiovascular Medicine, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan
| | - Hiroyuki Natsui
- Department of Cardiovascular Medicine, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan
| | - Takuya Koizumi
- Department of Cardiovascular Medicine, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan
| | - Motoki Nakao
- Department of Cardiovascular Medicine, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan
| | - Taro Koya
- Department of Cardiovascular Medicine, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan
| | - Hikaru Hagiwara
- Department of Cardiovascular Medicine, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan
| | - Rui Kamada
- Department of Cardiovascular Medicine, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan
| | - Taro Temma
- Department of Cardiovascular Medicine, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan
| | - Fuyuki Karube
- Laboratory of Histology and Cytology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan
| | - Fumino Fujiyama
- Laboratory of Histology and Cytology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan
| | - Toshihisa Anzai
- Department of Cardiovascular Medicine, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan
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7
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Dowrick JM, Tran K, Garrett AS, Anderson AJ, Nielsen PMF, Taberner AJ, Han JC. Work-loop contractions reveal that the afterload-dependent time course of cardiac Ca 2+ transients is modulated by preload. J Appl Physiol (1985) 2022; 133:663-675. [PMID: 35771221 PMCID: PMC9762964 DOI: 10.1152/japplphysiol.00137.2022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Preload and afterload dictate the dynamics of the cyclical work-loop contraction that the heart undergoes in vivo. Cellular Ca2+ dynamics drive contraction, but the effects of afterload alone on the Ca2+ transient are inconclusive. To our knowledge, no study has investigated whether the putative afterload dependence of the Ca2+ transient is preload dependent. This study is designed to provide the first insight into the Ca2+ handling of cardiac trabeculae undergoing work-loop contractions, with the aim to examine whether the conflicting afterload dependency of the Ca2+ transient can be accounted for by considering preload under isometric and physiological work-loop contractions. Thus, we subjected ex vivo rat right-ventricular trabeculae, loaded with the fluorescent dye Fura-2, to work-loop contractions over a wide range of afterloads at two preloads while measuring stress, length changes, and Ca2+ transients. Work-loop control was implemented with a real-time Windkessel model to mimic the contraction patterns of the heart in vivo. We extracted a range of metrics from the measured steady-state twitch stress and Ca2+ transients, including the amplitudes, time courses, rates of rise, and integrals. Results show that parameters of stress were afterload and preload dependent. In contrast, the parameters associated with Ca2+ transients displayed a mixed dependence on afterload and preload. Most notably, its time course was afterload dependent, an effect augmented at the greater preload. This study reveals that the afterload dependence of cardiac Ca2+ transients is modulated by preload, which brings the study of Ca2+ transients during isometric contractions into question when aiming to understand physiological Ca2+ handling.NEW & NOTEWORTHY This study is the first examination of Ca2+ handling in trabeculae undergoing work-loop contractions. These data reveal that reducing preload diminishes the influence of afterload on the decay phase of the cardiac Ca2+ transient. This is significant as it reconciles inconsistencies in the literature regarding the influence of external loads on cardiac Ca2+ handling. Furthermore, these findings highlight discrepancies between Ca2+ handling during isometric and work-loop contractions in cardiac trabeculae operating at their optimal length.
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Affiliation(s)
- Jarrah M. Dowrick
- 1Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | - Kenneth Tran
- 1Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | - Amy S. Garrett
- 1Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | - Alex J. Anderson
- 1Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | - Poul M. F. Nielsen
- 1Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand,2Department of Engineering Science, University of Auckland, Auckland, New Zealand
| | - Andrew J. Taberner
- 1Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand,2Department of Engineering Science, University of Auckland, Auckland, New Zealand
| | - June-Chiew Han
- 1Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
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8
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Chang GJ, Yeh YH, Chen WJ, Ko YS, Lai YJ, Lee YS. Candesartan Cilexetil Attenuates Arrhythmogenicity Following Pressure Overload in Rats via the Modulation of Cardiac Electrical and Structural Remodeling and Calcium Handling Dysfunction. J Am Heart Assoc 2022; 11:e024285. [PMID: 35862154 PMCID: PMC9375482 DOI: 10.1161/jaha.121.024285] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Background Cardiac hypertrophy is associated with abnormal electrophysiology and increased arrhythmia risk. This study assessed whether candesartan cilexetil, an angiotensin II type 1 receptor blocker, could suppress arrhythmogenecity by attenuating cardiac electrical remodeling and calcium mishandling in rats with pressure‐overload hypertrophy. Methods and Results Male Sprague‐Dawley rats were randomly subjected to abdominal aorta banding or sham procedure and received either candesartan cilexetil (3.0 mg/kg per day) or vehicle by gavage for 5 weeks. Pressure overload was characterized by compensated left ventricular (LV) hypertrophy and fibrosis, increased LV pressure and its decay time, and prolonged corrected QT interval, all of which were attenuated by candesartan cilexetil treatment. Candesartan cilexetil–treated banded rat hearts displayed shorter QT intervals and lower vulnerability to atrial and ventricular tachyarrhythmias than vehicle‐treated banded hearts. Candesartan cilexetil prevented banding‐induced prolonged action potential duration and reduced the occurrence of triggered activity in LV papillary muscles. In addition, the prolonged time to 50% cell relengthening and calcium transient decay time were normalized in LV myocytes from candesartan cilexetil–treated banded rats, along with a normalization of decreased SERCA2a (sarco[endo]plasmic reticulum calcium‐ATPase) expression in LV tissues. Furthermore, candesartan cilexetil normalized depressed transient outward potassium current densities and protein and mRNA levels of both voltage‐gated potassium 4.2 and 4.3 channel subunits (Kv4.2 and Kv4.3) in banded rats. Conclusions Candesartan cilexetil protects the heart from pressure overload‐induced adverse electrical remodeling by preserving potassium channel densities. In addition, calcium handling and its molecular regulation also improved after treatment. These beneficial effects may contribute to a lower susceptibility to arrhythmias in hearts from candesartan cilexetil–treated pressure‐overloaded rats.
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Affiliation(s)
- Gwo-Jyh Chang
- Graduate Institute of Clinical Medicinal Sciences College of Medicine Chang Gung University Tao-Yuan Taiwan.,Cardiovascular Division of Medicine Chang Gung Memorial Hospital Tao-Yuan Taiwan
| | - Yung-Hsin Yeh
- Cardiovascular Division of Medicine Chang Gung Memorial Hospital Tao-Yuan Taiwan
| | - Wei-Jan Chen
- Cardiovascular Division of Medicine Chang Gung Memorial Hospital Tao-Yuan Taiwan
| | - Yu-Shien Ko
- Cardiovascular Division of Medicine Chang Gung Memorial Hospital Tao-Yuan Taiwan
| | - Ying-Ju Lai
- Cardiovascular Division of Medicine Chang Gung Memorial Hospital Tao-Yuan Taiwan.,Department of Respiratory Therapy College of Medicine Chang Gung University Tao-Yuan Taiwan
| | - Yun-Shien Lee
- Genomic Medicine Research Core Laboratory Chang Gung Memorial Hospital Tao-Yuan Taiwan.,Department of Biotechnology Ming Chuan University Tao-Yuan Taiwan
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9
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Peng X, Li L, Lin R, Wang X, Liu X, Li Y, Ma C, Ruan Y, Liu N. Empagliflozin Ameliorates Ouabain-Induced Na + and Ca 2+ Dysregulations in Ventricular Myocytes in an Na +-Dependent Manner. Cardiovasc Drugs Ther 2022; 37:461-469. [PMID: 34982348 DOI: 10.1007/s10557-021-07311-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 12/28/2021] [Indexed: 02/06/2023]
Abstract
PURPOSE Sodium-glucose cotransporter 2 (SGLT2) inhibitors are a novel class of glucose-lowering agents that have improved clinical outcomes in patients with heart failure; however, their therapeutic mechanisms remain elusive. Although contradictory results have been reported, it has been proposed that improving Na+ homeostasis may be the underlying mechanism of action of SGLT2 inhibitors in heart failure treatment. This study explored whether empagliflozin ameliorates Na+ and Ca2+ handling disorders induced by ouabain in an Na+-dependent manner. METHODS Isolated ventricular myocytes of mice were incubated with ouabain to establish a cellular model of Na+ overload. Effects of empagliflozin on Na+ and Ca2+ handling were evaluated using an ionOptix system and a confocal microscope. Distinct cytosolic Na+ levels were established by incubating different ouabain concentrations (10, 50, and 100 μmol/L). RESULTS In the absence of ouabain, 1 μmol/L empagliflozin had a negligible impact on Na+ and Ca2+ handling in ventricular myocytes. Ouabain (50 μmol/L) significantly enhanced cytosolic Na+ levels and dysregulated Ca2+ handling, including an increased Ca2+ transient amplitude, elevated Ca2+ content in the sarcoplasmic reticulum, and enhanced spontaneous Ca2+ release normalized by treatment with 1 μmol/L empagliflozin within 10 min. All Na+ and Ca2+ handling abnormalities induced by ouabain were reversed by 1 μmol/L empagliflozin. The efficacy of empagliflozin was more potent at higher cytosolic Na+ levels. Pretreatment with the Na+/H+ exchanger (NHE) inhibitor (1 μmol/L cariporide) abolished the effects of empagliflozin. CONCLUSION Empagliflozin ameliorates ouabain-induced Na+ and Ca2+ handling disorders in a cytosolic Na+-dependent manner, potentially by inhibiting the NHE.
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Affiliation(s)
- Xiaodong Peng
- Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, Beijing, China.,National Clinical Research Center for Cardiovascular Diseases, Beijing, China
| | - Linling Li
- Department of Cardiology, Beijing ChuiYangLiu Hospital, Beijing, China
| | - Rong Lin
- North China Medical & Health Group XingTai Genernal Hospital, Xingtai, China
| | - Xuesi Wang
- Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, Beijing, China.,National Clinical Research Center for Cardiovascular Diseases, Beijing, China
| | - Xinmeng Liu
- Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, Beijing, China.,National Clinical Research Center for Cardiovascular Diseases, Beijing, China
| | - Yukun Li
- Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, Beijing, China.,National Clinical Research Center for Cardiovascular Diseases, Beijing, China
| | - Changsheng Ma
- Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, Beijing, China.,National Clinical Research Center for Cardiovascular Diseases, Beijing, China
| | - Yanfei Ruan
- Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, Beijing, China. .,National Clinical Research Center for Cardiovascular Diseases, Beijing, China.
| | - Nian Liu
- Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, Beijing, China. .,National Clinical Research Center for Cardiovascular Diseases, Beijing, China.
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10
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Kaplan AD, Joca HC, Boyman L, Greiser M. Calcium Signaling Silencing in Atrial Fibrillation: Implications for Atrial Sodium Homeostasis. Int J Mol Sci 2021; 22:10513. [PMID: 34638854 PMCID: PMC8508839 DOI: 10.3390/ijms221910513] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 09/14/2021] [Accepted: 09/14/2021] [Indexed: 12/19/2022] Open
Abstract
Atrial fibrillation (AF) is the most common type of cardiac arrhythmia, affecting more than 33 million people worldwide. Despite important advances in therapy, AF's incidence remains high, and treatment often results in recurrence of the arrhythmia. A better understanding of the cellular and molecular changes that (1) trigger AF and (2) occur after the onset of AF will help to identify novel therapeutic targets. Over the past 20 years, a large body of research has shown that intracellular Ca2+ handling is dramatically altered in AF. While some of these changes are arrhythmogenic, other changes counteract cellular arrhythmogenic mechanisms (Calcium Signaling Silencing). The intracellular Na+ concentration ([Na+])i is a key regulator of intracellular Ca2+ handling in cardiac myocytes. Despite its importance in the regulation of intracellular Ca2+ handling, little is known about [Na+]i, its regulation, and how it might be changed in AF. Previous work suggests that there might be increases in the late component of the atrial Na+ current (INa,L) in AF, suggesting that [Na+]i levels might be high in AF. Indeed, a pharmacological blockade of INa,L has been suggested as a treatment for AF. Here, we review calcium signaling silencing and changes in intracellular Na+ homeostasis during AF. We summarize the proposed arrhythmogenic mechanisms associated with increases in INa,L during AF and discuss the evidence from clinical trials that have tested the pharmacological INa,L blocker ranolazine in the treatment of AF.
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Affiliation(s)
- Aaron D. Kaplan
- Center for Biomedical Engineering and Technology, Department of Physiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (A.D.K.); (H.C.J.); (L.B.)
- Division of Cardiovascular Medicine, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Humberto C. Joca
- Center for Biomedical Engineering and Technology, Department of Physiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (A.D.K.); (H.C.J.); (L.B.)
| | - Liron Boyman
- Center for Biomedical Engineering and Technology, Department of Physiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (A.D.K.); (H.C.J.); (L.B.)
| | - Maura Greiser
- Center for Biomedical Engineering and Technology, Department of Physiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (A.D.K.); (H.C.J.); (L.B.)
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11
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Liu X, Wang S, Guo X, Li Y, Ogurlu R, Lu F, Prondzynski M, Buzon SDLS, Ma Q, Zhang D, Wang G, Cotton J, Guo Y, Xiao L, Milan DJ, Xu Y, Schlame M, Bezzerides VJ, Pu WT. Increased Reactive Oxygen Species-Mediated Ca 2+/Calmodulin-Dependent Protein Kinase II Activation Contributes to Calcium Handling Abnormalities and Impaired Contraction in Barth Syndrome. Circulation 2021; 143:1894-1911. [PMID: 33793303 PMCID: PMC8691127 DOI: 10.1161/circulationaha.120.048698] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
BACKGROUND Mutations in tafazzin (TAZ), a gene required for biogenesis of cardiolipin, the signature phospholipid of the inner mitochondrial membrane, causes Barth syndrome (BTHS). Cardiomyopathy and risk of sudden cardiac death are prominent features of BTHS, but the mechanisms by which impaired cardiolipin biogenesis causes cardiac muscle weakness and arrhythmia are poorly understood. METHODS We performed in vivo electrophysiology to define arrhythmia vulnerability in cardiac-specific TAZ knockout mice. Using cardiomyocytes derived from human induced pluripotent stem cells and cardiac-specific TAZ knockout mice as model systems, we investigated the effect of TAZ inactivation on Ca2+ handling. Through genome editing and pharmacology, we defined a molecular link between TAZ mutation and abnormal Ca2+ handling and contractility. RESULTS A subset of mice with cardiac-specific TAZ inactivation developed arrhythmias, including bidirectional ventricular tachycardia, atrial tachycardia, and complete atrioventricular block. Compared with wild-type controls, BTHS-induced pluripotent stem cell-derived cardiomyocytes had increased diastolic Ca2+ and decreased Ca2+ transient amplitude. BTHS-induced pluripotent stem cell-derived cardiomyocytes had higher levels of mitochondrial and cellular reactive oxygen species than wild-type controls, which activated CaMKII (Ca2+/calmodulin-dependent protein kinase II). Activated CaMKII phosphorylated the RYR2 (ryanodine receptor 2) on serine 2814, increasing Ca2+ leak through RYR2. Inhibition of this reactive oxygen species-CaMKII-RYR2 pathway through pharmacological inhibitors or genome editing normalized aberrant Ca2+ handling in BTHS-induced pluripotent stem cell-derived cardiomyocytes and improved their contractile function. Murine Taz knockout cardiomyocytes also exhibited elevated diastolic Ca2+ and decreased Ca2+ transient amplitude. These abnormalities were ameliorated by Ca2+/calmodulin-dependent protein kinase II or reactive oxygen species inhibition. CONCLUSIONS This study identified a molecular pathway that links TAZ mutation with abnormal Ca2+ handling and decreased cardiomyocyte contractility. This pathway may offer therapeutic opportunities to treat BTHS and potentially other diseases with elevated mitochondrial reactive oxygen species production.
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Affiliation(s)
- Xujie Liu
- Department of Cardiology, Boston Children’s Hospital, Boston, MA 02115, USA
- Department of Radiology, Basic Medical School, Chongqing Medical University, Chongqing, 400016, China
| | - Suya Wang
- Department of Cardiology, Boston Children’s Hospital, Boston, MA 02115, USA
| | - Xiaoling Guo
- Department of Cardiology, Boston Children’s Hospital, Boston, MA 02115, USA
- Center of Scientific Research, the Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical University, Wenzhou 325027, Zhejiang, China
| | - Yifei Li
- Key Laboratory of Birth Defects and Related Diseases of Women and Children of MOE, Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, Sichuan 610041, China
| | - Roza Ogurlu
- Department of Cardiology, Boston Children’s Hospital, Boston, MA 02115, USA
| | - Fujian Lu
- Department of Cardiology, Boston Children’s Hospital, Boston, MA 02115, USA
| | | | | | - Qing Ma
- Department of Cardiology, Boston Children’s Hospital, Boston, MA 02115, USA
| | - Donghui Zhang
- State key laboratory of Biocatalysis and Enzyme Engineering, School of Life Science, Hubei University, Wuhan, Hubei 430062, China
| | - Gang Wang
- Department of Cardiology, Boston Children’s Hospital, Boston, MA 02115, USA
| | - Justin Cotton
- Department of Cardiology, Boston Children’s Hospital, Boston, MA 02115, USA
- Harvard College, Cambridge, MA 02138, USA
| | - Yuxuan Guo
- Department of Cardiology, Boston Children’s Hospital, Boston, MA 02115, USA
| | - Ling Xiao
- Department of Cardiology, Massachusetts General Hospital, Boston, MA 02114, USA
| | - David J. Milan
- Department of Cardiology, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Yang Xu
- Department of Anesthesiology, New York University School of Medicine, New York, New York
| | - Michael Schlame
- Department of Anesthesiology, New York University School of Medicine, New York, New York
| | | | - William T. Pu
- Department of Cardiology, Boston Children’s Hospital, Boston, MA 02115, USA
- Harvard Stem Cell Institute, Cambridge, MA 02138, USA
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12
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da Costa TSR, Urias U, Negrao MV, Jordão CP, Passos CS, Gomes-Santos IL, Salemi VMC, Camargo AA, Brum PC, Oliveira EM, Hajjar LA, Chammas R, Filho RK, Negrao CE. Breast Cancer Promotes Cardiac Dysfunction Through Deregulation of Cardiomyocyte Ca 2+-Handling Protein Expression That is Not Reversed by Exercise Training. J Am Heart Assoc 2021; 10:e018076. [PMID: 33619982 PMCID: PMC8174298 DOI: 10.1161/jaha.120.018076] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Background Patients treated for breast cancer have a high incidence of cardiovascular complications. In this study, we evaluated the impact of breast cancer on cardiac function and cardiomyocyte Ca2+‐handling protein expression. We also investigated whether exercise training (ET) would prevent these potential alterations. Methods and Results Transgenic mice with spontaneous breast cancer (mouse mammary tumor virus–polyomavirus middle T antigen [MMTV‐PyMT+], n=15) and littermate mice with no cancer (MMTV‐PyMT−, n=14) were studied. For the ET analysis, MMTV‐PyMT+ were divided into sedentary (n=10) and exercise‐trained (n=12) groups. Cardiac function was evaluated by echocardiography with speckle‐tracking imaging. Exercise tolerance test was conducted on a treadmill. Both studies were performed when the tumor became palpable and when it reached 1 cm3. After euthanasia, Ca2+‐handling protein expression (Western blot) was evaluated. Exercise capacity was reduced in MMTV‐PyMT+ compared with MMTV‐PyMT− (Pinteraction=0.031). Longitudinal strain (Pgroup <0.001) and strain rate (Pgroup=0.030) were impaired. Cardiomyocyte phospholamban was increased (P=0.011), whereas phospho‐phospholamban and sodium/calcium exchanger were decreased (P=0.038 and P=0.017, respectively) in MMTV‐PyMT+. No significant difference in sarcoplasmic or endoplasmic reticulum calcium 2 ATPase (SERCA2a) was found. SERCA2a/phospholamban ratio was reduced (P=0.007). ET was not associated with increased exercise capacity. ET decreased left ventricular end‐systolic diameter (Pgroup=0.038) and end‐diastolic volume (Pgroup=0.026). Other morphological and functional cardiac parameters were not improved by ET in MMTV‐PyMT+. ET did not improve cardiomyocyte Ca2+‐handling protein expression. Conclusions Breast cancer is associated with decreased exercise capacity and subclinical left ventricular dysfunction in MMTV‐PyMT+, which is at least partly associated with dysregulation of cardiomyocyte Ca2+ handling. ET did not prevent or reverse these changes.
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Affiliation(s)
- Tassia S R da Costa
- Heart Institute (InCor) do Hospital das Clínicas Faculdade de Medicina Universidade de São Paulo Brasil.,Cancer Institute of the State of São Paulo Hospital das Clínicas Faculdade de Medicina Universidade de São Paulo Brasil
| | - Ursula Urias
- Heart Institute (InCor) do Hospital das Clínicas Faculdade de Medicina Universidade de São Paulo Brasil.,School of Physical Education and Sport Universidade de São Paulo Brasil
| | - Marcelo V Negrao
- Department of Thoracic/Head and Neck Medical Oncology The University of TexasMD Anderson Cancer Center Houston TX
| | - Camila P Jordão
- Heart Institute (InCor) do Hospital das Clínicas Faculdade de Medicina Universidade de São Paulo Brasil
| | - Clévia S Passos
- Heart Institute (InCor) do Hospital das Clínicas Faculdade de Medicina Universidade de São Paulo Brasil
| | - Igor L Gomes-Santos
- Heart Institute (InCor) do Hospital das Clínicas Faculdade de Medicina Universidade de São Paulo Brasil.,Edwin L. Steele Laboratories for Tumor Biology Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School Boston MA
| | - Vera Maria C Salemi
- Heart Institute (InCor) do Hospital das Clínicas Faculdade de Medicina Universidade de São Paulo Brasil
| | | | - Patricia C Brum
- School of Physical Education and Sport Universidade de São Paulo Brasil
| | | | - Ludhmila A Hajjar
- Heart Institute (InCor) do Hospital das Clínicas Faculdade de Medicina Universidade de São Paulo Brasil.,Cancer Institute of the State of São Paulo Hospital das Clínicas Faculdade de Medicina Universidade de São Paulo Brasil
| | - Roger Chammas
- Cancer Institute of the State of São Paulo Hospital das Clínicas Faculdade de Medicina Universidade de São Paulo Brasil
| | - Roberto K Filho
- Heart Institute (InCor) do Hospital das Clínicas Faculdade de Medicina Universidade de São Paulo Brasil
| | - Carlos E Negrao
- Heart Institute (InCor) do Hospital das Clínicas Faculdade de Medicina Universidade de São Paulo Brasil.,School of Physical Education and Sport Universidade de São Paulo Brasil
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13
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Hsu SS, Lin YS, Liang WZ. Mechanism of action of a diterpene alkaloid hypaconitine on cytotoxicity and inhibitory effect of BAPTA-AM in HCN-2 neuronal cells. Clin Exp Pharmacol Physiol 2021; 48:801-810. [PMID: 33609056 DOI: 10.1111/1440-1681.13482] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 01/11/2021] [Accepted: 01/28/2021] [Indexed: 11/29/2022]
Abstract
Hypaconitine, a neuromuscular blocker, is a diterpene alkaloid found in the root of Aconitum carmichaelii. Although hypaconitine was shown to affect various physiological responses in neurological models, the effect of hypaconitine on cell viability and the mechanism of its action of Ca2+ handling is elusive in cortical neurons. This study examined whether hypaconitine altered viability and Ca2+ signalling in HCN-2 neuronal cell lines. Cell viability was measured by the cell proliferation reagent (WST-1). Cytosolic Ca2+ concentrations [Ca2+ ]i was measured by the Ca2+ -sensitive fluorescent dye fura-2. In HCN-2 cells, hypaconitine (10-50 μmol/L) induced cytotoxicity and [Ca2+ ]i rises in a concentration-dependent manner. Removal of extracellular Ca2+ partially reduced the hypaconitine's effect on [Ca2+ ]i rises. Furthermore, chelation of cytosolic Ca2+ with BAPTA-AM reduced hypaconitine's cytotoxicity. In Ca2+ -containing medium, hypaconitine-induced Ca2+ entry was inhibited by modulators (2-APB and SKF96365) of store-operated Ca2+ channels and a protein kinase C (PKC) inhibitor (GF109203X). Hypaconitine induced Mn2+ influx indirectly suggesting that hypaconitine evoked Ca2+ entry. In Ca2+ -free medium, treatment with the endoplasmic reticulum Ca2+ pump inhibitor thapsigargin abolished hypaconitine-induced [Ca2+ ]i rises. Conversely, treatment with hypaconitine inhibited thapsigargin-induced [Ca2+ ]i rises. However, inhibition of phospholipase C (PLC) with U73122 did not inhibit hypaconitine-induced [Ca2+ ]i rises. Together, hypaconitine caused cytotoxicity that was linked to preceding [Ca2+ ]i rises by Ca2+ influx via store-operated Ca2+ entry involved PKC regulation and evoking PLC-independent Ca2+ release from the endoplasmic reticulum. Because BAPTA-AM loading only partially reversed hypaconitine-induced cell death, it suggests that hypaconitine induced a second Ca2+ -independent cytotoxicity in HCN-2 cells.
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Affiliation(s)
- Shu-Shong Hsu
- Department of Neurosurgery, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan.,Department of Neurosurgery, National Defense Medical Center, Taipei, Taiwan.,College of Health and Nursing, Meiho University, Pingtung, Taiwan
| | - Yung-Shang Lin
- Department of Neurosurgery, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | - Wei-Zhe Liang
- Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan.,Department of Pharmacy and Master Program, College of Pharmacy and Health Care, Tajen University, Pingtung County, Taiwan
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14
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Belchior ACS, Freire-júnior DD, Da Costa CP, Vassallo DV, dos Santos L, Padilha AS. Post-weaning protein malnutrition induces myocardial dysfunction associated with oxidative stress and altered calcium handling proteins in adult rats. J Physiol Biochem 2021; 77:261-72. [PMID: 33555533 DOI: 10.1007/s13105-021-00792-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 01/22/2021] [Indexed: 10/22/2022]
Abstract
Hypercaloric low-protein diet may lead to a state of malnutrition found in the low-income population of Northeastern Brazil. Although malnutrition during critical periods in the early life is associated with cardiovascular diseases in adulthood, the mechanisms of cardiac dysfunction are still unclear. Here we studied the effects of post-weaning malnutrition due to low protein intake induced by a regional basic diet on the cardiac contractility of young adult rats. In vivo arterial hemodynamic and in vitro myocardial contractility were evaluated in 3-month-old rats. Additionally, protein content of the sarcoplasmic reticulum Ca(2+)-ATPase (SERCA), total phospholamban (PLB) and phosphorylated at serine 16 (p-Ser(16)-PLB), α2-subunit of the Na(+)/K(+)-ATPase (α2-NKA), and Na(+)/Ca(2+) exchanger (NXC) and in situ production of superoxide anion (O2(-)) were measured in the heart. Blood pressure and heart rate increased in the post-weaning malnourished (PWM) rats. Moreover, malnutrition decreased twitch force and inotropic responses of the isolated cardiac muscle. Protein expression of SERCA, PLB/SERCA, and p-Ser(16)-PLB/PLB ratios and α2-NKA were decreased without changing NCX. The contraction dependent on transsarcolemmal calcium influx was unchanged but responsiveness to Ca(2+) and tetanic peak contractions were impaired in the PWM group. Myocardial O2(-) production was significantly increased by PWM. Our data demonstrated that this hypercaloric low-protein diet in rats is associated with myocardial dysfunction, altered expression of major calcium handling proteins, and increased local oxidative stress. These findings reinforce the attention needed for pediatric care, since chronic malnutrition in early life is related to increased cardiovascular risk in adulthood. Graphical Abstract.
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15
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Rodríguez-Sánchez E, Navarro-García JA, González-Lafuente L, Aceves-Ripoll J, Vázquez-Sánchez S, Poveda J, Mercado-García E, Corbacho-Alonso N, Calvo-Bonacho E, Fernández-Velasco M, Álvarez-Llamas G, Barderas MG, Ruilope LM, Ruiz-Hurtado G. Oxidized Low-Density Lipoprotein Associates with Ventricular Stress in Young Adults and Triggers Intracellular Ca 2+ Alterations in Adult Ventricular Cardiomyocytes. Antioxidants (Basel) 2020; 9:antiox9121213. [PMID: 33271910 PMCID: PMC7761043 DOI: 10.3390/antiox9121213] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 11/20/2020] [Accepted: 11/26/2020] [Indexed: 12/13/2022] Open
Abstract
Oxidized low-density lipoprotein (oxLDL) is associated with cardiac damage and causes injury to multiple cell types. We aimed to investigate the role of oxLDL in ventricular stress. We first examined the association between circulating oxLDL and N-terminal pro-brain natriuretic peptide (NT-proBNP), a marker of myocardial stress, in young subjects (30-50 years) with or without stable coronary artery disease (SCAD). oxLDL and NT-proBNP were significantly higher in subjects at high cardiovascular risk (CVR) than in subjects at low CVR and were associated independently of traditional CVR factors and C-reactive protein. Furthermore, the levels of oxLDL and NT-proBNP were significantly lower in subjects with SCAD than in peers at high CVR. To determine the intracellular mechanisms involved in the cardiac effects of oxLDL, we analyzed the in vitro effect of oxLDL on intracellular Ca2+ handling in adult rat ventricular cardiomyocytes using confocal microscopy. Acute challenge of adult ventricular cardiomyocytes to oxLDL reduced systolic Ca2+ transients and sarcoplasmic reticulum Ca2+ load. Moreover, diastolic spontaneous Ca2+ leak increased significantly after acute exposure to oxLDL. Thus, we demonstrate that oxLDL associates with NT-proBNP in young subjects, and can directly induce Ca2+ mishandling in adult ventricular cardiomyoyctes, predisposing cardiomyocytes to cardiac dysfunction and arrhythmogenicity.
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Affiliation(s)
- Elena Rodríguez-Sánchez
- Cardiorenal Translational Laboratory, Institute of Research i+12, Hospital Universitario 12 de Octubre, 28041 Madrid, Spain; (E.R.-S.); (J.A.N.-G.); (L.G.-L.); (J.A.-R.); (S.V.-S.); (J.P.); (E.M.-G.); (L.M.R.)
| | - José Alberto Navarro-García
- Cardiorenal Translational Laboratory, Institute of Research i+12, Hospital Universitario 12 de Octubre, 28041 Madrid, Spain; (E.R.-S.); (J.A.N.-G.); (L.G.-L.); (J.A.-R.); (S.V.-S.); (J.P.); (E.M.-G.); (L.M.R.)
| | - Laura González-Lafuente
- Cardiorenal Translational Laboratory, Institute of Research i+12, Hospital Universitario 12 de Octubre, 28041 Madrid, Spain; (E.R.-S.); (J.A.N.-G.); (L.G.-L.); (J.A.-R.); (S.V.-S.); (J.P.); (E.M.-G.); (L.M.R.)
| | - Jennifer Aceves-Ripoll
- Cardiorenal Translational Laboratory, Institute of Research i+12, Hospital Universitario 12 de Octubre, 28041 Madrid, Spain; (E.R.-S.); (J.A.N.-G.); (L.G.-L.); (J.A.-R.); (S.V.-S.); (J.P.); (E.M.-G.); (L.M.R.)
| | - Sara Vázquez-Sánchez
- Cardiorenal Translational Laboratory, Institute of Research i+12, Hospital Universitario 12 de Octubre, 28041 Madrid, Spain; (E.R.-S.); (J.A.N.-G.); (L.G.-L.); (J.A.-R.); (S.V.-S.); (J.P.); (E.M.-G.); (L.M.R.)
| | - Jonay Poveda
- Cardiorenal Translational Laboratory, Institute of Research i+12, Hospital Universitario 12 de Octubre, 28041 Madrid, Spain; (E.R.-S.); (J.A.N.-G.); (L.G.-L.); (J.A.-R.); (S.V.-S.); (J.P.); (E.M.-G.); (L.M.R.)
| | - Elisa Mercado-García
- Cardiorenal Translational Laboratory, Institute of Research i+12, Hospital Universitario 12 de Octubre, 28041 Madrid, Spain; (E.R.-S.); (J.A.N.-G.); (L.G.-L.); (J.A.-R.); (S.V.-S.); (J.P.); (E.M.-G.); (L.M.R.)
| | - Nerea Corbacho-Alonso
- Department of Vascular Physiopathology, Hospital Nacional de Parapléjicos, SESCAM, 45004 Toledo, Spain; (N.C.-A.); (M.G.B.)
| | | | - María Fernández-Velasco
- IdiPAZ Institute for Health Research/Centro de Investigación Biomédica en Red de Enfermedades Cardiovasculares, CIBER-CV, 28029 Madrid, Spain;
| | | | - María G. Barderas
- Department of Vascular Physiopathology, Hospital Nacional de Parapléjicos, SESCAM, 45004 Toledo, Spain; (N.C.-A.); (M.G.B.)
| | - Luis M. Ruilope
- Cardiorenal Translational Laboratory, Institute of Research i+12, Hospital Universitario 12 de Octubre, 28041 Madrid, Spain; (E.R.-S.); (J.A.N.-G.); (L.G.-L.); (J.A.-R.); (S.V.-S.); (J.P.); (E.M.-G.); (L.M.R.)
- Hypertension Unit, Hospital Universitario 12 de Octubre, 28041 Madrid, Spain
- CIBER-CV, Hospital Universitario 12 de Octubre, 28041 Madrid, Spain
- European University of Madrid, Madrid, Spain
| | - Gema Ruiz-Hurtado
- Cardiorenal Translational Laboratory, Institute of Research i+12, Hospital Universitario 12 de Octubre, 28041 Madrid, Spain; (E.R.-S.); (J.A.N.-G.); (L.G.-L.); (J.A.-R.); (S.V.-S.); (J.P.); (E.M.-G.); (L.M.R.)
- Hypertension Unit, Hospital Universitario 12 de Octubre, 28041 Madrid, Spain
- CIBER-CV, Hospital Universitario 12 de Octubre, 28041 Madrid, Spain
- Correspondence: ; Tel.: +34-91-390-8001
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16
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Gil-Fernández M, Navarro-García JA, Val-Blasco A, González-Lafuente L, Martínez JC, Rueda A, Tamayo M, Morgado JL, Zaragoza C, Ruilope LM, Delgado C, Ruiz-Hurtado G, Fernández-Velasco M. Genetic Deletion of NOD1 Prevents Cardiac Ca 2+ Mishandling Induced by Experimental Chronic Kidney Disease. Int J Mol Sci 2020; 21:E8868. [PMID: 33238586 DOI: 10.3390/ijms21228868] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 11/16/2020] [Accepted: 11/19/2020] [Indexed: 12/23/2022] Open
Abstract
Risk of cardiovascular disease (CVD) increases considerably as renal function declines in chronic kidney disease (CKD). Nucleotide-binding oligomerization domain-containing protein 1 (NOD1) has emerged as a novel innate immune receptor involved in both CVD and CKD. Following activation, NOD1 undergoes a conformational change that allows the activation of the receptor-interacting serine/threonine protein kinase 2 (RIP2), promoting an inflammatory response. We evaluated whether the genetic deficiency of Nod1 or Rip2 in mice could prevent cardiac Ca2+ mishandling induced by sixth nephrectomy (Nx), a model of CKD. We examined intracellular Ca2+ dynamics in cardiomyocytes from Wild-type (Wt), Nod1-/- and Rip2-/- sham-operated or nephrectomized mice. Compared with Wt cardiomyocytes, Wt-Nx cells showed an impairment in the properties and kinetics of the intracellular Ca2+ transients, a reduction in both cell shortening and sarcoplasmic reticulum Ca2+ load, together with an increase in diastolic Ca2+ leak. Cardiomyocytes from Nod1-/--Nx and Rip2-/--Nx mice showed a significant amelioration in Ca2+ mishandling without modifying the kidney impairment induced by Nx. In conclusion, Nod1 and Rip2 deficiency prevents the intracellular Ca2+ mishandling induced by experimental CKD, unveiling new innate immune targets for the development of innovative therapeutic strategies to reduce cardiac complications in patients with CKD.
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17
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Zhang H, Zhang S, Wang W, Wang K, Shen W. A Mathematical Model of the Mouse Atrial Myocyte With Inter-Atrial Electrophysiological Heterogeneity. Front Physiol 2020; 11:972. [PMID: 32848887 PMCID: PMC7425199 DOI: 10.3389/fphys.2020.00972] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Accepted: 07/16/2020] [Indexed: 12/20/2022] Open
Abstract
Biophysically detailed mathematical models of cardiac electrophysiology provide an alternative to experimental approaches for investigating possible ionic mechanisms underlying the genesis of electrical action potentials and their propagation through the heart. The aim of this study was to develop a biophysically detailed mathematical model of the action potentials of mouse atrial myocytes, a popular experimental model for elucidating molecular and cellular mechanisms of arrhythmogenesis. Based on experimental data from isolated mouse atrial cardiomyocytes, a set of mathematical equations for describing the biophysical properties of membrane ion channel currents, intracellular Ca2+ handling, and Ca2+-calmodulin activated protein kinase II and β-adrenergic signaling pathways were developed. Wherever possible, membrane ion channel currents were modeled using Markov chain formalisms, allowing detailed representation of channel kinetics. The model also considered heterogeneous electrophysiological properties between the left and the right atrial cardiomyocytes. The developed model was validated by its ability to reproduce the characteristics of action potentials and Ca2+ transients, matching quantitatively to experimental data. Using the model, the functional roles of four K+ channel currents in atrial action potential were evaluated by channel block simulations, results of which were quantitatively in agreement with existent experimental data. To conclude, this newly developed model of mouse atrial cardiomyocytes provides a powerful tool for investigating possible ion channel mechanisms of atrial electrical activity at the cellular level and can be further used to investigate mechanisms underlying atrial arrhythmogenesis.
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Affiliation(s)
- Henggui Zhang
- Department of Physics and Astronomy, Biological Physics Group, School of Physics & Astronomy, The University of Manchester, Manchester, United Kingdom.,Peng Cheng Laboratory, Shenzhen, China
| | - Shanzhuo Zhang
- Department of Physics and Astronomy, Biological Physics Group, School of Physics & Astronomy, The University of Manchester, Manchester, United Kingdom.,School of Computer Science and Technology, Harbin Institute of Technology, Harbin, China
| | - Wei Wang
- Department of Physics and Astronomy, Biological Physics Group, School of Physics & Astronomy, The University of Manchester, Manchester, United Kingdom.,Peng Cheng Laboratory, Shenzhen, China.,Shenzhen Key Laboratory of Visual Object Detection and Recognition, Harbin Institute of Technology, Shenzhen, China
| | - Kuanquan Wang
- School of Computer Science and Technology, Harbin Institute of Technology, Harbin, China
| | - Weijian Shen
- Department of Physics and Astronomy, Biological Physics Group, School of Physics & Astronomy, The University of Manchester, Manchester, United Kingdom
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18
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Gejl KD, Andersson EP, Nielsen J, Holmberg HC, Ørtenblad N. Effects of Acute Exercise and Training on the Sarcoplasmic Reticulum Ca 2+ Release and Uptake Rates in Highly Trained Endurance Athletes. Front Physiol 2020; 11:810. [PMID: 32733285 PMCID: PMC7359889 DOI: 10.3389/fphys.2020.00810] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 06/18/2020] [Indexed: 11/16/2022] Open
Abstract
Little is presently known about the effects of acute high-intensity exercise or training on release and uptake of Ca2+ by the sarcoplasmic reticulum (SR). The aims here were to characterize this regulation in highly trained athletes following (1) repeated bouts of high-intensity exercise and (2) a period of endurance training including high-intensity sessions. Eleven cross-country skiers (25 ± 4 years, 65 ± 4 mL O2⋅kg−1⋅min–1) performed four self-paced sprint time-trials (STT 1-4) lasting ≈ 4 min each (STT 1–4) and separated by 45 min of recovery; while 19 triathletes and road cyclists (25 ± 4 years, 65 ± 5 mL O2⋅kg−1⋅min–1) completed 4 weeks of endurance training in combination with three sessions of high-intensity interval cycling per week. Release (μmol⋅g–1 prot⋅min–1) and uptake [tau (s)] of Ca2+ by SR vesicles isolated from m. triceps brachii and m. vastus lateralis were determined before and after STT 1 and 4 in the skiers and in m. vastus lateralis before and after the 4 weeks of training in the endurance athletes. The Ca2+ release rate was reduced by 17–18% in both limbs already after STT 1 (arms: 2.52 ± 0.74 to 2.08 ± 0.60; legs: 2.41 ± 0.45 to 1.98 ± 0.51, P < 0.0001) and attenuated further following STT 4 (arms: 2.24 ± 0.67 to 1.95 ± 0.45; legs: 2.13 ± 0.51 to 1.83 ± 0.36, P < 0.0001). Also, there was a tendency toward an impairment in the SR Ca2+ uptake from pre STT1 to post STT4 in both arms and legs (arms: from 22.0 ± 3.7 s to 25.3 ± 6.0 s; legs: from 22.5 ± 4.7 s to 25.5 ± 7.7 s, P = 0.05). Endurance training combined with high-intensity exercise increased the Ca2+ release rate by 9% (1.76 ± 0.38 to 1.91 ± 0.44, P = 0.009), without altering the Ca2+ uptake (29.6 ± 7.0 to 29.1 ± 8.7 s; P = 0.98). In conclusion, the Ca2+ release and uptake rates by SR in exercising limbs of highly trained athletes declines gradually by repetitive bouts of high-intensity exercise. We also demonstrate, for the first time, that the SR Ca2+ release rate can be enhanced by a specific program of training in highly trained athletes, which may have important implications for performance parameters.
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Affiliation(s)
- Kasper Degn Gejl
- Department of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark
| | - Erik P Andersson
- Swedish Winter Sports Research Centre, Department of Health Sciences, Mid Sweden University, Östersund, Sweden
| | - Joachim Nielsen
- Department of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark
| | - Hans-Christer Holmberg
- Swedish Winter Sports Research Centre, Department of Health Sciences, Mid Sweden University, Östersund, Sweden.,Department of Physiology and Pharmacology, Biomedicum C5, Karolinska Institute, Stockholm, Sweden
| | - Niels Ørtenblad
- Department of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark
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19
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Sun GC, Jan CR, Liang WZ. Exploring the impact of a naturally occurring sapogenin diosgenin on underlying mechanisms of Ca 2+ movement and cytotoxicity in human prostate cancer cells. Environ Toxicol 2020; 35:395-403. [PMID: 31709706 DOI: 10.1002/tox.22876] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 10/07/2019] [Accepted: 10/10/2019] [Indexed: 06/10/2023]
Abstract
Literature has shown that diosgenin, a naturally occurring sapogenin, inducedcytotoxic effects in many cancer models. This study investigated the effect of diosgenin on intracellular Ca2+ concentration ([Ca2+ ]i) and cytotoxicity in PC3 human prostate cancer cells. Diosgenin (250-1000 μM) caused [Ca2+ ]i rises which was reduced by Ca2+ removal. Treatment with thapsigargin eliminated diosgenin-induced [Ca2+ ]i increases. In contrast, incubation with diosgeninabolished thapsigargin-caused [Ca2+ ]i increases. Suppression of phospholipase C with U73122 eliminated diosgenin-caused [Ca2+ ]i increases. Diosgenin evoked Mn2+ influx suggesting that diosgenin induced Ca2+ entry. Diosgenin-induced Ca2+ influx was suppressed by PMA, GF109203X, and nifedipine, econazole, or SKF96365. Diosgenin (250-600 μM) concentration-dependently decreased cell viability. However, diosgenin-induced cytotoxicity was not reversed by chelation of cytosolic Ca2+ with BAPTA/AM. Together, diosgenin evoked [Ca2+ ]i increases via Ca2+ release and Ca2+ influx, and caused Ca2+ -non-associated deathin PC3 cells. These findings reveal a newtherapeutic potential of diosgenin for human prostate cancer.
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Affiliation(s)
- Gwo-Ching Sun
- Department of Anesthesiology, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan, Republic of China
- Department of Anesthesiology, Faculty of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan, Republic of China
| | - Chung-Ren Jan
- Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan, Republic of China
| | - Wei-Zhe Liang
- Department of Pharmacy, Tajen University, Pingtung, Taiwan, Republic of China
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20
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Abstract
Energetic demand from high-intensity exercise can easily exceed ATP synthesis rates of mitochondria leading to a reliance on anaerobic metabolism. The reliance on anaerobic metabolism results in the accumulation of intracellular metabolites, namely inorganic phosphate (Pi) and hydrogen (H+), that are closely associated with exercise-induced reductions in power. Cellular and molecular studies have revealed several steps where these metabolites impair contractile function demonstrating a causal role in fatigue. Elevated Pi or H+ directly inhibits force and power of the cross-bridge and decreases myofibrillar Ca2+ sensitivity, whereas Pi also inhibits Ca2+ release from the sarcoplasmic reticulum (SR). When both metabolites are elevated, they act synergistically to cause marked reductions in power, indicating that fatigue during high-intensity exercise has a bioenergetic basis.
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Affiliation(s)
- Christopher W Sundberg
- Department of Biological Sciences, Marquette University, Milwaukee, WI.,Department of Physical Therapy, Marquette University, Milwaukee, WI
| | - Robert H Fitts
- Department of Biological Sciences, Marquette University, Milwaukee, WI
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21
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Abstract
The Emax-Pressure-Volume Area (PVA)-VO2 framework proposed by Dr. Suga for canine hearts has dramatically advanced the field of cardiac mechanical work and energetics, i.e., mechanoenergetics. He and his collaborators investigated mechanoenergetics in the left ventricle (LV) of excised, cross-circulated canine heart preparations. We instituted the excised cross-circulated rat whole heart preparations and found a curvilinear end-systolic pressure-volume relation (ESPVR) in the rat LV, in contrast to the linear ESPVR in canine, rabbit, and human LVs. Although Emax, the slope of the linear ESPVR, could be used as an index of LV contractility, it was not applicable for evaluating LV contractility in the rat LV. Thus, we proposed a new index of contractility, equivalent Emax (eEmax) in the rat LV. We also found a linear VO2-PVA relationship in the rat LV. Here, we introduce the methods for the preparation of excised, cross-circulated rat whole hearts and the eEmax-PVA-VO2 framework in the rat LV. Using this method, we can obtain accurate LV volume and myocardial O2 consumption in real time for estimating cardiac mechanoenergetics, which is very challenging in in vivo experiments.
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22
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Badone B, Ronchi C, Kotta MC, Sala L, Ghidoni A, Crotti L, Zaza A. Calmodulinopathy: Functional Effects of CALM Mutations and Their Relationship With Clinical Phenotypes. Front Cardiovasc Med 2018; 5:176. [PMID: 30619883 PMCID: PMC6297375 DOI: 10.3389/fcvm.2018.00176] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Accepted: 11/22/2018] [Indexed: 12/16/2022] Open
Abstract
In spite of the widespread role of calmodulin (CaM) in cellular signaling, CaM mutations lead specifically to cardiac manifestations, characterized by remarkable electrical instability and a high incidence of sudden death at young age. Penetrance of the mutations is surprisingly high, thus postulating a high degree of functional dominance. According to the clinical patterns, arrhythmogenesis in CaM mutations can be attributed, in the majority of cases, to either prolonged repolarization (as in long-QT syndrome, LQTS phenotype), or to instability of the intracellular Ca2+ store (as in catecholamine-induced tachycardias, CPVT phenotype). This review discusses how mutations affect CaM signaling function and how this may relate to the distinct arrhythmia phenotypes/mechanisms observed in patients; this involves mechanistic interpretation of negative dominance and mutation-specific CaM-target interactions. Knowledge of the mechanisms involved may allow critical approach to clinical manifestations and aid in the development of therapeutic strategies for "calmodulinopathies," a recently identified nosological entity.
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Affiliation(s)
- Beatrice Badone
- Department of Biotechnology and Bioscience, University of Milano-Bicocca, Milan, Italy
| | - Carlotta Ronchi
- Department of Biotechnology and Bioscience, University of Milano-Bicocca, Milan, Italy
| | - Maria-Christina Kotta
- Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, Istituto Auxologico Italiano, IRCCS, Milan, Italy
| | - Luca Sala
- Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, Istituto Auxologico Italiano, IRCCS, Milan, Italy
| | - Alice Ghidoni
- Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, Istituto Auxologico Italiano, IRCCS, Milan, Italy
| | - Lia Crotti
- Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, Istituto Auxologico Italiano, IRCCS, Milan, Italy
- Department of Medicine and Surgery, University of Milano-Bicocca, Milan, Italy
- Department of Cardiovascular, Neural and Metabolic Sciences, San Luca Hospital, Istituto Auxologico Italiano, IRCCS, Milan, Italy
| | - Antonio Zaza
- Department of Biotechnology and Bioscience, University of Milano-Bicocca, Milan, Italy
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23
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Molina CE, Abu-Taha IH, Wang Q, Roselló-Díez E, Kamler M, Nattel S, Ravens U, Wehrens XHT, Hove-Madsen L, Heijman J, Dobrev D. Profibrotic, Electrical, and Calcium-Handling Remodeling of the Atria in Heart Failure Patients With and Without Atrial Fibrillation. Front Physiol 2018; 9:1383. [PMID: 30356673 PMCID: PMC6189336 DOI: 10.3389/fphys.2018.01383] [Citation(s) in RCA: 67] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Accepted: 09/11/2018] [Indexed: 01/01/2023] Open
Abstract
Atrial fibrillation (AF) and heart failure (HF) are common cardiovascular diseases that often co-exist. Animal models have suggested complex AF-promoting atrial structural, electrical, and Ca2+-handling remodeling in the setting of HF, but data in human samples are scarce, particularly regarding Ca2+-handling remodeling. Here, we evaluated atrial remodeling in patients with severe left ventricular (LV) dysfunction (HFrEF), long-standing persistent ('chronic') AF (cAF) or both (HFrEF-cAF), and sinus rhythm controls with normal LV function (Ctl) using western blot in right-atrial tissue, sharp-electrode action potential (AP) measurements in atrial trabeculae and voltage-clamp experiments in isolated right-atrial cardiomyocytes. Compared to Ctl, expression of profibrotic markers (collagen-1a, fibronectin, periostin) was higher in HFrEF and HFrEF-cAF patients, indicative of structural remodeling. Connexin-43 expression was reduced in HFrEF patients, but not HFrEF-cAF patients. AP characteristics were unchanged in HFrEF, but showed classical indices of electrical remodeling in cAF and HFrEF-cAF (prolonged AP duration at 20% and shorter AP duration at 50% and 90% repolarization). L-type Ca2+ current (ICa,L) was significantly reduced in HFrEF, cAF and HFrEF-cAF, without changes in voltage-dependence. Potentially proarrhythmic spontaneous transient-inward currents were significantly more frequent in HFrEF and HFrEF-cAF compared to Ctl, likely resulting from increased sarcoplasmic reticulum (SR) Ca2+ load (integrated caffeine-induced current) in HFrEF and increased ryanodine-receptor (RyR2) single-channel open probability in HFrEF and HFrEF-cAF. Although expression and phosphorylation of the SR Ca2+-ATPase type-2a (SERCA2a) regulator phospholamban were unchanged in HFrEF and HFrEF-cAF patients, protein levels of SERCA2a were increased in HFrEF-cAF and sarcolipin expression was decreased in both HFrEF and HFrEF-cAF, likely increasing SR Ca2+ uptake and load. RyR2 protein levels were decreased in HFrEF and HFrEF-cAF patients, but junctin levels were higher in HFrEF and relative Ser2814-RyR2 phosphorylation levels were increased in HFrEF-cAF, both potentially contributing to the greater RyR2 open probability. These novel insights into the molecular substrate for atrial arrhythmias in HF-patients position Ca2+-handling abnormalities as a likely trigger of AF in HF patients, which subsequently produces electrical remodeling that promotes the maintenance of the arrhythmia. Our new findings may have important implications for the development of novel treatment options for AF in the context of HF.
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Affiliation(s)
- Cristina E Molina
- Institute of Pharmacology, West German Heart and Vascular Center, University Duisburg-Essen, Essen, Germany.,Biomedical Research Institute Barcelona (IIBB-CSIC) and Biomedical Research Institute Sant Pau, Hospital de Sant Pau, Barcelona, Spain.,Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Issam H Abu-Taha
- Institute of Pharmacology, West German Heart and Vascular Center, University Duisburg-Essen, Essen, Germany
| | - Qiongling Wang
- Cardiovascular Research Institute - Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX, United States
| | - Elena Roselló-Díez
- Cardiac Surgery Department, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
| | - Marcus Kamler
- Department of Thoracic and Cardiovascular Surgery, West German Heart and Vascular Center Essen, University Hospital Essen, Essen, Germany
| | - Stanley Nattel
- Institute of Pharmacology, West German Heart and Vascular Center, University Duisburg-Essen, Essen, Germany.,Department of Medicine, Montreal Heart Institute and Université de Montréal, Montreal, QC, Canada.,Department of Pharmacology and Therapeutics, McGill University, Montreal, QC, Canada
| | - Ursula Ravens
- Institute of Experimental Cardiovascular Medicine, University Heart Center Freiburg, University of Freiburg, Bad Krozingen, Germany.,Institute of Physiology, Medical Faculty Carl Gustav Carus, TU Dresden, Dresden, Germany
| | - Xander H T Wehrens
- Cardiovascular Research Institute - Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX, United States
| | - Leif Hove-Madsen
- Biomedical Research Institute Barcelona (IIBB-CSIC) and Biomedical Research Institute Sant Pau, Hospital de Sant Pau, Barcelona, Spain
| | - Jordi Heijman
- Department of Cardiology, CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, Netherlands
| | - Dobromir Dobrev
- Institute of Pharmacology, West German Heart and Vascular Center, University Duisburg-Essen, Essen, Germany
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24
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Yamaguchi Y, Iribe G, Kaneko T, Takahashi K, Numaga-Tomita T, Nishida M, Birnbaumer L, Naruse K. TRPC3 participates in angiotensin II type 1 receptor-dependent stress-induced slow increase in intracellular Ca 2+ concentration in mouse cardiomyocytes. J Physiol Sci 2018; 68:153-164. [PMID: 28105583 PMCID: PMC10718017 DOI: 10.1007/s12576-016-0519-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Accepted: 12/26/2016] [Indexed: 11/26/2022]
Abstract
When a cardiac muscle is held in a stretched position, its [Ca2+] transient increases slowly over several minutes in a process known as stress-induced slow increase in intracellular Ca2+ concentration ([Ca2+]i) (SSC). Transient receptor potential canonical (TRPC) 3 forms a non-selective cation channel regulated by the angiotensin II type 1 receptor (AT1R). In this study, we investigated the role of TRPC3 in the SSC. Isolated mouse ventricular myocytes were electrically stimulated and subjected to sustained stretch. An AT1R blocker, a phospholipase C inhibitor, and a TRPC3 inhibitor suppressed the SSC. These inhibitors also abolished the observed SSC-like slow increase in [Ca2+]i induced by angiotensin II, instead of stretch. Furthermore, the SSC was not observed in TRPC3 knockout mice. Simulation and immunohistochemical studies suggest that sarcolemmal TRPC3 is responsible for the SSC. These results indicate that sarcolemmal TRPC3, regulated by AT1R, causes the SSC.
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Affiliation(s)
- Yohei Yamaguchi
- Department of Cardiovascular Physiology, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University, Okayama, 700-8558, Japan
| | - Gentaro Iribe
- Department of Cardiovascular Physiology, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University, Okayama, 700-8558, Japan.
| | - Toshiyuki Kaneko
- Department of Physiology, Asahikawa Medical University, Asahikawa, Hokkaido, 078-8510, Japan
| | - Ken Takahashi
- Department of Cardiovascular Physiology, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University, Okayama, 700-8558, Japan
| | - Takuro Numaga-Tomita
- Division of Cardiocirculatory Signaling, Okazaki Institute for Integrative Bioscience (National Institute for Physiological Sciences), National Institutes of Natural Sciences, Okazaki, Aichi, 444-8787, Japan
| | - Motohiro Nishida
- Division of Cardiocirculatory Signaling, Okazaki Institute for Integrative Bioscience (National Institute for Physiological Sciences), National Institutes of Natural Sciences, Okazaki, Aichi, 444-8787, Japan
| | - Lutz Birnbaumer
- Neurobiology Laboratory, National Institute of Environmental Health Science, Research Triangle Park, NC, 27709, USA
| | - Keiji Naruse
- Department of Cardiovascular Physiology, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University, Okayama, 700-8558, Japan
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25
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Val-Blasco A, Navarro-García JA, Tamayo M, Piedras MJ, Prieto P, Delgado C, Ruiz-Hurtado G, Rozas-Romero L, Gil-Fernández M, Zaragoza C, Boscá L, Fernández-Velasco M. Deficiency of NOD1 Improves the β-Adrenergic Modulation of Ca 2+ Handling in a Mouse Model of Heart Failure. Front Physiol 2018; 9:702. [PMID: 29962957 PMCID: PMC6010671 DOI: 10.3389/fphys.2018.00702] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 05/22/2018] [Indexed: 02/05/2023] Open
Abstract
Heart failure (HF) is a complex syndrome characterized by cardiac dysfunction, Ca2+ mishandling, and chronic activation of the innate immune system. Reduced cardiac output in HF leads to compensatory mechanisms via activation of the adrenergic nervous system. In turn, chronic adrenergic overstimulation induces pro-arrhythmic events, increasing the rate of sudden death in failing patients. Nucleotide-binding oligomerization domain-containing protein 1 (NOD1) is an innate immune modulator that plays a key role in HF progression. NOD1 deficiency in mice prevents Ca2+ mishandling in HF under basal conditions, but its role during β-adrenergic stimulation remains unknown. Here, we evaluated whether NOD1 regulates the β-adrenergic modulation of Ca2+ signaling in HF. Ca2+ dynamics were examined before and after isoproterenol perfusion in cardiomyocytes isolated from healthy and from post-myocardial infarction (PMI) wild-type (WT) and Nod1-/- mice. Isoproterenol administration induced similar effects on intracellular [Ca2+]i transients, cell contraction, and sarcoplasmic reticulum (SR)-Ca2+ load in healthy WT and Nod1-/- cells. However, compared with WT-PMI cells, isoproterenol exposure induced a significant increase in the [Ca2+]i transients and cell contraction parameters in Nod1-/--PMI cells, which mainly due to an increase in SR-Ca2+ load. NOD1 deficiency also prevented the increase in diastolic Ca2+ leak (Ca2+ waves) induced by isoproterenol in PMI cells. mRNA levels of β1 and β2 adrenergic receptors were significantly higher in Nod1-/--PMI hearts vs WT-PMI hearts. Healthy cardiomyocytes pre-treated with the selective agonist of NOD1, iE-DAP, and perfused with isoproterenol showed diminished [Ca2+]i transients amplitude, cell contraction, and SR-Ca2+ load compared with vehicle-treated cells. iE-DAP-treated cells also presented increased diastolic Ca2+ leak under β-adrenergic stimulation. The selectivity of iE-DAP on Ca2+ handling was validated by pre-treatment with the inactive analog of NOD1, iE-Lys. Overall, our data establish that NOD1 deficiency improves the β-adrenergic modulation of Ca2+ handling in failing hearts.
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Affiliation(s)
- Almudena Val-Blasco
- Innate Immune Response Group, Instituto de Investigación Hospital Universitario La Paz, La Paz University Hospital, Madrid, Spain
| | - Jose A. Navarro-García
- Cardiorenal Translational Laboratory and Hypertension Unit, Institute of Research i+12, Hospital Universitario 12 de Octubre, Madrid, Spain
| | - Maria Tamayo
- Departamento de Bioquímica, Facultad de Medicina, Instituto de Investigaciones Biomédicas Alberto Sols, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Maria J. Piedras
- Department of Anatomy, Faculty of Health Sciences, Francisco de Vitoria University (UFV), Pozuelo de Alarcón, Spain
| | - Patricia Prieto
- Departamento de Bioquímica, Facultad de Medicina, Instituto de Investigaciones Biomédicas Alberto Sols, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Carmen Delgado
- Departamento de Bioquímica, Facultad de Medicina, Instituto de Investigaciones Biomédicas Alberto Sols, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Gema Ruiz-Hurtado
- Cardiorenal Translational Laboratory and Hypertension Unit, Institute of Research i+12, Hospital Universitario 12 de Octubre, Madrid, Spain
| | - Laura Rozas-Romero
- Innate Immune Response Group, Instituto de Investigación Hospital Universitario La Paz, La Paz University Hospital, Madrid, Spain
| | - Marta Gil-Fernández
- Innate Immune Response Group, Instituto de Investigación Hospital Universitario La Paz, La Paz University Hospital, Madrid, Spain
| | - Carlos Zaragoza
- Unidad de Investigación Cardiovascular, Universidad Francisco de Vitoria, Hospital Universitario Ramón y Cajal (IRYCIS), CIBERCV, Madrid, Spain
| | - Lisardo Boscá
- Departamento de Bioquímica, Facultad de Medicina, Instituto de Investigaciones Biomédicas Alberto Sols, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - María Fernández-Velasco
- Innate Immune Response Group, Instituto de Investigación Hospital Universitario La Paz, La Paz University Hospital, Madrid, Spain
- *Correspondence: María Fernández-Velasco, ;
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Souza Bomfim GH, Mendez-Lopez I, Arranz-Tagarro JA, Ferraz Carbonel AA, Roman-Campos D, Padín JF, Garcia AG, Jurkiewicz A, Jurkiewicz NH. Functional Upregulation of STIM-1/Orai-1-Mediated Store-Operated Ca2+ Contributing to the Hypertension Development Elicited by Chronic EtOH Consumption. Curr Vasc Pharmacol 2017; 15:265-281. [PMID: 28155613 DOI: 10.2174/1570161115666170201122750] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Revised: 01/04/2017] [Accepted: 01/04/2017] [Indexed: 11/22/2022]
Abstract
BACKGROUND Chronic ethanol (EtOH) consumption has been associated with deleterious effects on the cardiovascular system by abnormal calcium (Ca2+) handling. Store-operated Ca2+ entry (SOCE) is related to cardiovascular remodeling which leads to the hypertension development, and the coupling between STIM-1 (ER Ca2+ sensor) and Orai-1 (channel pore) is a key mechanism to control SOCE through of store-operated Ca2+ channels (SOCCs). However, the role of STIM-1/Orai-1-mediated SOCE and its cross-talk with EtOH-triggered vascular remodeling and hypertension remain poorly understood. We address this subject in the present study by evaluating how chronic EtOH consumption induces alterations in Ca2+ handling via SOCE. METHODS Male Wistar Kyoto (WKY) and Spontaneously Hypertensive (SHR) rats were subjected to the intake of increasing EtOH concentrations (5-20%, for 30 days). Systolic blood pressure (SBP) and EtOH concentration were measured; cardiovascular remodeling was assessed by histomorphometry; and function/ expression of STIM-1/Orai-1-mediated Ca2+ influx were evaluated by isometric contraction and western blot experiments. RESULTS Compared to the WKY-Control, our results show that: (1) chronic EtOH consumption caused a significant elevation of SBP in both strains; (2) cardiac hypertrophy and hypertrophic aortic wall remodeling much more pronounced in WKY-EtOH; (3) decreased capacity of ER to store and release Ca2+; (4) increased STIM-1/Orai-1-mediated SOCCs activation, which was selectively inhibited by YM-58483; and (5) increased expression of STIM-1 in WKY-EtOH and SHR-Control rats. CONCLUSION These findings suggest that hypertrophic aortic remodeling and abnormal contraction triggered mainly by Ca2+ overload via STIM-1/Orai-1-mediated SOCE through SOCCs are involved hypertension developed by EtOH consumption.
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Affiliation(s)
| | - Iago Mendez-Lopez
- Instituto Teófilo Hernando de I+D del Medicamento, Facultad de Medicina de la Universidad Autónoma de Madrid (UAM), Madrid, Spain
| | - Juan Alberto Arranz-Tagarro
- Instituto Teófilo Hernando de I+D del Medicamento, Facultad de Medicina de la Universidad Autónoma de Madrid (UAM), Madrid, Spain
| | - Adriana Aparecida Ferraz Carbonel
- Departamento de Morfologia e Genetica, Escola Paulista de Medicina da Universidade Federal de Sao Paulo (UNIFESP), Sao Paulo, Brazil
| | - Danilo Roman-Campos
- Departamento de Biofísica, Escola Paulista de Medicina da Universidade Federal de Sao Paulo (UNIFESP), Sao Paulo, Brazil
| | - Juan Fernando Padín
- Instituto Teófilo Hernando de I+D del Medicamento, Facultad de Medicina de la Universidad Autónoma de Madrid (UAM), Madrid, Spain
| | - Antonio Garcia Garcia
- Instituto Teófilo Hernando de I+D del Medicamento, Facultad de Medicina de la Universidad Autónoma de Madrid (UAM), Madrid, Spain
| | - Aron Jurkiewicz
- Departamento de Farmacologia, Escola Paulista de Medicina da Universidade Federal de Sao Paulo (UNIFESP), Sao Paulo, Brazil
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Lu LH, Li C, Wang QY, Zhang Q, Zhang Y, Meng H, Wang Y, Wang W. Cardioprotective effects of Qishen Granule () on sarcoplasmic reticulum Ca 2+ handling in heart failure rats. Chin J Integr Med 2017; 23:510-517. [PMID: 28497395 DOI: 10.1007/s11655-017-2809-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Indexed: 12/22/2022]
Abstract
OBJECTIVE To assess the effects of Qishen Granule (, QSG) on sarcoplasmic reticulum (SR) Ca2+ handling in heart failure (HF) model of rats and to explore the underlying molecular mechanisms. METHODS HF rat models were induced by left anterior descending coronary artery ligation surgery and high-fat diet feeding. Rats were randomly divided into sham (n=10), model (n=10), QSG (n=12, 2.2 g/kg daily) and metoprolol groups (n=12, 10.5 mg/kg daily). The therapeutic effects of QSG were evaluated by echocardiography and blood lipid testing. Intracellular Ca2+ concentration and sarco-endoplasmic reticulum ATPase 2a (SERCA2a) activity were detected by specifific assay kits. Expressions of the critical regulators in SR Ca2+ handling were evaluated by Western blot and real-time quantitative polymerase chain reaction. RESULTS HF model of rats developed ventricular remodeling accompanied with calcium overload and defective Ca2+ release-uptake cycling in cardiomyocytes. Treatment with QSG improved contractive function, attenuated ventricular remodeling and reduced the basal intracellular Ca2+ level. QSG prevented defective Ca2+ leak by attenuating hyperphosphorylation of ryanodine receptor 2, inhibiting expression of protein kinase A and up-regulating transcriptional expression of protein phosphatase 1. QSG also restored Ca2+ uptake by up-regulating expression and activity of SERCA2a and promoting phosphorylation of phospholamban. CONCLUSION QSG restored SR Ca2+ cycling in HF rats and served as an ideal alternative drug for treating HF.
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Affiliation(s)
- Ling-Hui Lu
- School of Preclinical Medicine, Beijing University of Chinese Medicine, Beijing, 100029, China
| | - Chun Li
- Modern Research Center for Traditional Chinese Medicine, Beijing University of Chinese Medicine, Beijing, 100029, China
| | - Qi-Yan Wang
- School of Life Sciences, Beijing University of Chinese Medicine, Beijing, 100029, China
| | - Qian Zhang
- School of Preclinical Medicine, Beijing University of Chinese Medicine, Beijing, 100029, China
| | - Yi Zhang
- Modern Research Center for Traditional Chinese Medicine, Beijing University of Chinese Medicine, Beijing, 100029, China
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing, 100102, China
| | - Hui Meng
- Modern Research Center for Traditional Chinese Medicine, Beijing University of Chinese Medicine, Beijing, 100029, China
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing, 100102, China
| | - Yong Wang
- School of Life Sciences, Beijing University of Chinese Medicine, Beijing, 100029, China
| | - Wei Wang
- School of Preclinical Medicine, Beijing University of Chinese Medicine, Beijing, 100029, China.
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28
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Gamu D, Trinh A, Fajardo VA, Bombardier E, Tupling AR. Sarcolipin expression is not required for the mitochondrial enzymatic response to physical activity or diet. J Appl Physiol (1985) 2017; 122:1276-1283. [PMID: 28183820 DOI: 10.1152/japplphysiol.00833.2016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Revised: 02/06/2017] [Accepted: 02/06/2017] [Indexed: 11/22/2022] Open
Abstract
In mice, transgenic manipulation of Ca2+-handling proteins is sufficient to alter the metabolic phenotype of muscle. We have previously shown that ablation of sarcolipin (SLN), a regulatory protein and uncoupler of sarco(endo)plasmic reticulum Ca2+-ATPases, leads to excessive diet-induced obesity and glucose intolerance in mice. However, it is unclear how loss of SLN per se affects muscle oxidative capacity and the ability of mitochondria to adapt to physiological stimuli, such as exercise training or calorie overload. To address this question, Sln-/- and wild-type (WT) littermates were given access to voluntary running wheels or underwent a treadmill training protocol for 8 wk. Furthermore, a separate group of mice were given a high-fat diet (42% kcal from fat for 8 wk) to determine whether the excessively obese phenotype of Sln-/- mice is associated with altered oxidative capacity. While voluntary running was insufficient to elicit mitochondrial adaptations, treadmill-trained mice showed significant increases (P < 0.05) in the maximal activities of succinate dehydrogenase (+11%), citrate synthase (+12%), cytochrome oxidase (COX: +17%), along with increased protein expression of cytochrome c (+34%) and COX IV (+28%), which were irrespective of SLN expression. Lastly, no changes in the activities of mitochondrial marker enzymes existed with high-fat feeding, regardless of genotype. Together, these findings indicate that SLN is not required for the regulation of oxidative capacity in response to physiological stress, namely exercise or caloric surfeit.NEW & NOTEWORTHY Sarcolipin (SLN) has gained considerable attention for its uncoupling role of sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA). Because of SLN's ability to alter both cellular energy use and cytosolic [Ca2+], the potential exists for a regulatory role of mitochondrial biogenesis. Herein, we show skeletal muscle oxidative capacity to be unaltered in mice lacking SLN following exercise training or high-fat feeding. Our results contrast with published studies of SLN-overexpressing mice, possibly owing to supraphysiological uncoupling of SERCA.
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Affiliation(s)
- Daniel Gamu
- Department of Kinesiology, University of Waterloo, Waterloo, Ontario, Canada
| | - Anton Trinh
- Department of Kinesiology, University of Waterloo, Waterloo, Ontario, Canada
| | - Val A Fajardo
- Department of Kinesiology, University of Waterloo, Waterloo, Ontario, Canada
| | - Eric Bombardier
- Department of Kinesiology, University of Waterloo, Waterloo, Ontario, Canada
| | - A Russell Tupling
- Department of Kinesiology, University of Waterloo, Waterloo, Ontario, Canada
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Wang D, Shan Y, Huang Y, Tang Y, Chen Y, Li R, Yang J, Huang C. Vasostatin-1 Stops Structural Remodeling and Improves Calcium Handling via the eNOS-NO-PKG Pathway in Rat Hearts Subjected to Chronic β-Adrenergic Receptor Activation. Cardiovasc Drugs Ther 2016; 30:455-64. [PMID: 27595734 DOI: 10.1007/s10557-016-6687-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
PURPOSE Chronically elevated catecholamine levels activate cardiac β-adrenergic receptors, which play a vital role in the pathogenesis of heart failure. Evidence suggests that vasostatin-1 (VS-1) exerts anti-adrenergic effects on isolated and perfused hearts in vitro. Whether VS-1 ameliorates hypertrophy/remodeling by inducing the chronic activation of β-adrenergic receptors is unknown. The present study aims to test the efficacy of using VS-1 to treat the advanced hypertrophy/remodeling that result from chronic β-adrenergic receptor activation and to determine the cellular and molecular mechanisms that underlie this response. METHODS AND RESULT Rats were subjected to infusion with either isoprenaline (ISO, 5 mg/kg/d), ISO plus VS-1 (30 mg/kg/d) or placebo for 2 weeks. VS-1 suppressed chamber dilation, myocyte hypertrophy and fibrosis and improved in vivo heart function in the rats subjected to ISO infusion. VS-1 increased phosphorylated nitric oxide synthase levels and induced the activation of protein kinase G. VS-1 also deactivated multiple hypertrophy signaling pathways that were triggered by the chronic activation of β-adrenergic receptors, such as the phosphoinositide-3 kinase (PI3K)/Akt and Ca2+/calmodulin-dependent kinase (CaMK-II) pathways. Myocytes isolated from ISO + VS-1 hearts displayed higher Ca2+ transients, shorter Ca2+ decays, higher sarcoplasmic reticulum Ca2+ levels and higher L-type Ca2+ current densities than the ISO rat hearts. VS-1 treatment restored the protein expression of sarcoplasmic reticulum Ca2+ uptake ATPase, phospholamban and Cav1.2, indicating improved calcium handling. CONCLUSIONS Chronic VS-1 treatment inhibited the progression of hypertrophy, fibrosis, and chamber remodeling, and improved cardiac function in a rat model of ISO infusion. In addition, Ca2+ handling and its molecular modulation were also improved by VS-1. The beneficial effects of VS-1 on cardiac remodeling may be mediated by the enhanced activation of the eNOS-cGMP-PKG pathway.
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30
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Weirich J. [Remodeling of the aging heart : Sinus node dysfunction and atrial fibrillation]. Herzschrittmacherther Elektrophysiol 2017; 28:29-38. [PMID: 28204916 DOI: 10.1007/s00399-017-0485-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Accepted: 01/12/2017] [Indexed: 12/19/2022]
Abstract
The incidence of both sinus node dysfunction (SND) and atrial fibrillation (AF) increases with age. SND and AF frequently coexist. Likewise, they are often associated with cardiovascular diseases. Both arrhythmias share similar pathomechanisms such as structural and functional remodeling, i. e., degenerative fibrosis and altered Ca2+ handling, respectively. A growing body of evidence suggests an important role for the CamKII (Ca2+/calmodulin-dependent protein kinase II) in structural as well as in functional remodeling. In the sinus node, remodeling leads to degenerative fibrosis and as a consequence to sinus node arrest or to reentry (brady/tachycardia). In the atrium, remodeling sets the conditions for reentry and its triggering mechanisms, especially the conditions for triggered activity on the basis of delayed afterdepolarizations (DAD). Thus, SND and AF seem to be different phenotypes of related pathophysiological mechanisms. On the other hand, it remains controversial as to whether SND causes AF or vice versa.
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Affiliation(s)
- Jörg Weirich
- Institut für Physiologie, Abteilung II, Medizinische Fakultät, Albert-Ludwigs-Universität Freiburg, Hermann-Herder-Str. 7, 79104, Freiburg, Deutschland.
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31
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Neyroud D. Protein Fragmentation As a Regulatory Mechanism: Insights from Two Different Ca 2+ Channels, RyR1 and IP 3R. Front Physiol 2017; 7:655. [PMID: 28101060 PMCID: PMC5209332 DOI: 10.3389/fphys.2016.00655] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Accepted: 12/14/2016] [Indexed: 11/13/2022] Open
Affiliation(s)
- Daria Neyroud
- Faculty of Biology and Medicine, Institute of Sport Sciences, University of Lausanne Lausanne, Switzerland
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32
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Sorrentino A, Borghetti G, Zhou Y, Cannata A, Meo M, Signore S, Anversa P, Leri A, Goichberg P, Qanud K, Jacobson JT, Hintze TH, Rota M. Hyperglycemia induces defective Ca2+ homeostasis in cardiomyocytes. Am J Physiol Heart Circ Physiol 2016; 312:H150-H161. [PMID: 27881388 DOI: 10.1152/ajpheart.00737.2016] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Revised: 11/21/2016] [Accepted: 11/21/2016] [Indexed: 01/03/2023]
Abstract
Diabetes and other metabolic conditions characterized by elevated blood glucose constitute important risk factors for cardiovascular disease. Hyperglycemia targets myocardial cells rendering ineffective mechanical properties of the heart, but cellular alterations dictating the progressive deterioration of cardiac function with metabolic disorders remain to be clarified. In the current study, we examined the effects of hyperglycemia on cardiac function and myocyte physiology by employing mice with high blood glucose induced by administration of streptozotocin, a compound toxic to insulin-producing β-cells. We found that hyperglycemia initially delayed the electrical recovery of the heart, whereas cardiac function became defective only after ~2 mo with this condition and gradually worsened with time. Prolonged hyperglycemia was associated with increased chamber dilation, thinning of the left ventricle (LV), and myocyte loss. Cardiomyocytes from hyperglycemic mice exhibited defective Ca2+ transients before the appearance of LV systolic defects. Alterations in Ca2+ transients involved enhanced spontaneous Ca2+ releases from the sarcoplasmic reticulum (SR), reduced cytoplasmic Ca2+ clearance, and declined SR Ca2+ load. These defects have important consequences on myocyte contraction, relaxation, and mechanisms of rate adaptation. Collectively, our data indicate that hyperglycemia alters intracellular Ca2+ homeostasis in cardiomyocytes, hindering contractile activity and contributing to the manifestation of the diabetic cardiomyopathy. NEW & NOTEWORTHY We have investigated the effects of hyperglycemia on cardiomyocyte physiology and ventricular function. Our results indicate that defective Ca2+ handling is a critical component of the progressive deterioration of cardiac performance of the diabetic heart.
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Affiliation(s)
- Andrea Sorrentino
- Departments of Anesthesia and Medicine and Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Giulia Borghetti
- Departments of Anesthesia and Medicine and Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Yu Zhou
- Departments of Anesthesia and Medicine and Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Antonio Cannata
- Departments of Anesthesia and Medicine and Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Marianna Meo
- Departments of Anesthesia and Medicine and Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Sergio Signore
- Departments of Anesthesia and Medicine and Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Piero Anversa
- Departments of Anesthesia and Medicine and Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts.,Fondazione Cardiocentro Ticino, University of Zurich, Lugano, Switzerland
| | - Annarosa Leri
- Departments of Anesthesia and Medicine and Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts.,Fondazione Cardiocentro Ticino, University of Zurich, Lugano, Switzerland
| | - Polina Goichberg
- Departments of Anesthesia and Medicine and Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Khaled Qanud
- Department of Physiology, New York Medical College, Valhalla, New York; and
| | - Jason T Jacobson
- Department of Physiology, New York Medical College, Valhalla, New York; and.,Department of Cardiology, Westchester Medical Center, Valhalla, New York
| | - Thomas H Hintze
- Department of Physiology, New York Medical College, Valhalla, New York; and
| | - Marcello Rota
- Departments of Anesthesia and Medicine and Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts; .,Department of Physiology, New York Medical College, Valhalla, New York; and
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33
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Preininger MK, Jha R, Maxwell JT, Wu Q, Singh M, Wang B, Dalal A, Mceachin ZT, Rossoll W, Hales CM, Fischbach PS, Wagner MB, Xu C. A human pluripotent stem cell model of catecholaminergic polymorphic ventricular tachycardia recapitulates patient-specific drug responses. Dis Model Mech 2016; 9:927-39. [PMID: 27491078 PMCID: PMC5047684 DOI: 10.1242/dmm.026823] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Accepted: 07/13/2016] [Indexed: 01/07/2023] Open
Abstract
Although β-blockers can be used to eliminate stress-induced ventricular arrhythmias in patients with catecholaminergic polymorphic ventricular tachycardia (CPVT), this treatment is unsuccessful in ∼25% of cases. Induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) generated from these patients have potential for use in investigating the phenomenon, but it remains unknown whether they can recapitulate patient-specific drug responses to β-blockers. This study assessed whether the inadequacy of β-blocker therapy in an individual can be observed in vitro using patient-derived CPVT iPSC-CMs. An individual with CPVT harboring a novel mutation in the type 2 cardiac ryanodine receptor (RyR2) was identified whose persistent ventricular arrhythmias during β-blockade with nadolol were abolished during flecainide treatment. iPSC-CMs generated from this patient and two control individuals expressed comparable levels of excitation-contraction genes, but assessment of the sarcoplasmic reticulum Ca(2+) leak and load relationship revealed intracellular Ca(2+) homeostasis was altered in the CPVT iPSC-CMs. β-adrenergic stimulation potentiated spontaneous Ca(2+) waves and unduly frequent, large and prolonged Ca(2+) sparks in CPVT compared with control iPSC-CMs, validating the disease phenotype. Pursuant to the patient's in vivo responses, nadolol treatment during β-adrenergic stimulation achieved negligible reduction of Ca(2+) wave frequency and failed to rescue Ca(2+) spark defects in CPVT iPSC-CMs. In contrast, flecainide reduced both frequency and amplitude of Ca(2+) waves and restored the frequency, width and duration of Ca(2+) sparks to baseline levels. By recapitulating the improved response of an individual with CPVT to flecainide compared with β-blocker therapy in vitro, these data provide new evidence that iPSC-CMs can capture basic components of patient-specific drug responses.
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MESH Headings
- Adrenergic beta-Antagonists/pharmacology
- Adrenergic beta-Antagonists/therapeutic use
- Arrhythmias, Cardiac/drug therapy
- Arrhythmias, Cardiac/physiopathology
- Biomarkers/metabolism
- Calcium/metabolism
- Calcium Signaling/drug effects
- Catecholamines/metabolism
- Cell Differentiation/drug effects
- Cell Lineage/drug effects
- Electrophysiological Phenomena/drug effects
- Female
- Flecainide/pharmacology
- Flecainide/therapeutic use
- Homeostasis/drug effects
- Humans
- Induced Pluripotent Stem Cells/drug effects
- Induced Pluripotent Stem Cells/metabolism
- Male
- Middle Aged
- Models, Biological
- Myocytes, Cardiac/drug effects
- Myocytes, Cardiac/metabolism
- Myocytes, Cardiac/pathology
- Pedigree
- Receptors, Adrenergic, beta/metabolism
- Tachycardia, Ventricular/drug therapy
- Tachycardia, Ventricular/pathology
- Tachycardia, Ventricular/physiopathology
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Affiliation(s)
- Marcela K Preininger
- Division of Pediatric Cardiology, Department of Pediatrics, Emory University School of Medicine and Children's Healthcare of Atlanta, Atlanta, GA 30322, USA Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA 30322, USA
| | - Rajneesh Jha
- Division of Pediatric Cardiology, Department of Pediatrics, Emory University School of Medicine and Children's Healthcare of Atlanta, Atlanta, GA 30322, USA
| | - Joshua T Maxwell
- Division of Pediatric Cardiology, Department of Pediatrics, Emory University School of Medicine and Children's Healthcare of Atlanta, Atlanta, GA 30322, USA Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA 30322, USA
| | - Qingling Wu
- Division of Pediatric Cardiology, Department of Pediatrics, Emory University School of Medicine and Children's Healthcare of Atlanta, Atlanta, GA 30322, USA Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA 30322, USA
| | - Monalisa Singh
- Division of Pediatric Cardiology, Department of Pediatrics, Emory University School of Medicine and Children's Healthcare of Atlanta, Atlanta, GA 30322, USA
| | - Bo Wang
- Division of Pediatric Cardiology, Department of Pediatrics, Emory University School of Medicine and Children's Healthcare of Atlanta, Atlanta, GA 30322, USA
| | - Aarti Dalal
- Division of Pediatric Cardiology, Department of Pediatrics, Emory University School of Medicine and Children's Healthcare of Atlanta, Atlanta, GA 30322, USA
| | - Zachary T Mceachin
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA 30322, USA Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA Laboratory of Translational Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Wilfried Rossoll
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA Laboratory of Translational Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Chadwick M Hales
- Department of Neurology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Peter S Fischbach
- Division of Pediatric Cardiology, Department of Pediatrics, Emory University School of Medicine and Children's Healthcare of Atlanta, Atlanta, GA 30322, USA
| | - Mary B Wagner
- Division of Pediatric Cardiology, Department of Pediatrics, Emory University School of Medicine and Children's Healthcare of Atlanta, Atlanta, GA 30322, USA Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA 30322, USA
| | - Chunhui Xu
- Division of Pediatric Cardiology, Department of Pediatrics, Emory University School of Medicine and Children's Healthcare of Atlanta, Atlanta, GA 30322, USA Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA 30322, USA
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Llano-Diez M, Cheng AJ, Jonsson W, Ivarsson N, Westerblad H, Sun V, Cacciani N, Larsson L, Bruton J. Impaired Ca(2+) release contributes to muscle weakness in a rat model of critical illness myopathy. Crit Care 2016; 20:254. [PMID: 27510990 PMCID: PMC5050561 DOI: 10.1186/s13054-016-1417-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Accepted: 07/20/2016] [Indexed: 01/01/2023]
Abstract
BACKGROUND Critical illness myopathy is an acquired skeletal muscle disorder with severe myosin loss and muscle weakness frequently seen in intensive care unit (ICU) patients. It is unknown if impaired excitation-contraction coupling contributes to the muscle weakness. METHODS We used a unique ICU model where rats were deeply sedated, post-synaptically pharmacologically paralyzed, mechanically ventilated and closely monitored for up to ten days. Single intact fibers from the flexor digitorum brevis muscle were isolated and used to measure force and free myoplasmic [Ca(2+)] ([Ca(2+)]i) during tetanic contractions. RESULTS Fibers from ICU rats had 80 % lower tetanic [Ca(2+)]i and produced only 15 % of the force seen in fibers from sham-operated (SHAM) rats. In the presence of 5 mM caffeine, tetanic [Ca(2+)]i was similar in fibers from ICU and SHAM rats but force was 50 % lower in fibers from ICU rats than SHAM rats. Confocal imaging showed disrupted tetanic [Ca(2+)]i transients in fibers from ICU rats compared to SHAM rats. Western blots showed similar levels of Na(+) channel and dihydropyridine receptor (DHPR) protein expression, whereas ryanodine receptor (RyR) and sarco-endoplasmic reticulum Ca(2+) ATPase 1 (SERCA1) expression was markedly lower in muscle of ICU rats than in SHAM rats. Immunohistochemical analysis showed that distribution of Na(+) channel and DHPR protein on the sarcolemma was disrupted in fibers from ICU rats compared with SHAM rats. CONCLUSIONS These results suggest that impaired SR Ca(2+) release contributes to the muscle weakness seen in patients in ICU.
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Affiliation(s)
- Monica Llano-Diez
- Department of Physiology & Pharmacology, Karolinska Institutet, von Eulers väg, 8, 2 floor, Stockholm, 171 77, Sweden
| | - Arthur J Cheng
- Department of Physiology & Pharmacology, Karolinska Institutet, von Eulers väg, 8, 2 floor, Stockholm, 171 77, Sweden
| | - William Jonsson
- Department of Physiology & Pharmacology, Karolinska Institutet, von Eulers väg, 8, 2 floor, Stockholm, 171 77, Sweden
| | - Niklas Ivarsson
- Department of Physiology & Pharmacology, Karolinska Institutet, von Eulers väg, 8, 2 floor, Stockholm, 171 77, Sweden
| | - Håkan Westerblad
- Department of Physiology & Pharmacology, Karolinska Institutet, von Eulers väg, 8, 2 floor, Stockholm, 171 77, Sweden
| | - Vic Sun
- Department of Physiology & Pharmacology, Karolinska Institutet, von Eulers väg, 8, 2 floor, Stockholm, 171 77, Sweden
| | - Nicola Cacciani
- Department of Physiology & Pharmacology, Karolinska Institutet, von Eulers väg, 8, 2 floor, Stockholm, 171 77, Sweden
| | - Lars Larsson
- Department of Physiology & Pharmacology, Karolinska Institutet, von Eulers väg, 8, 2 floor, Stockholm, 171 77, Sweden
| | - Joseph Bruton
- Department of Physiology & Pharmacology, Karolinska Institutet, von Eulers väg, 8, 2 floor, Stockholm, 171 77, Sweden.
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Abstract
Post-extrasystolic potentiation (PESP) describes the phenomenon of increased contractility of the beat following an extrasystole and has been attributed to changes in Ca(2+) homeostasis. While this effect has long been regarded to be a normal physiological phenomenon, a number of reports describe an enhanced potentiation of the post-extrasystolic beat in heart failure patients. The exact mechanism of this increased PESP is unknown, but disruption of normal Ca(2+) handling in heart failure may be the underlying cause. The use of PESP as a prognostic marker or therapeutic intervention have recently regained new attention, however, the value of the application of PESP in the clinic is still under debate. In this review, the mechanism of PESP with regard to Ca(2+) in the normal and failing heart will be discussed and the possible diagnostic and therapeutic role of this phenomenon will be explored.
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Affiliation(s)
| | - Marc A Vos
- University Medical Center Utrecht, Utrecht, The Netherlands
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36
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Bell JR, Erickson JR, Delbridge LM. Ca(2+) /calmodulin dependent kinase II: a critical mediator in determining reperfusion outcomes in the heart? Clin Exp Pharmacol Physiol 2015; 41:940-6. [PMID: 25283076 DOI: 10.1111/1440-1681.12301] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2014] [Revised: 07/31/2014] [Accepted: 08/13/2014] [Indexed: 12/27/2022]
Abstract
Ischaemic heart disease is a major cause of death and disability in the Western world, and a substantial health burden. Cardiomyocyte Ca(2+) overload is known to significantly contribute to contractile dysfunction and myocyte death in ischaemia and reperfusion, and significant advancements have been made in identifying the downstream mediators and cellular origins of this Ca(2+) mismanagement. Ca(2+) /calmodulin-dependent kinase II (CaMKII) is recognized as an important mediator linking pathological changes in subcellular environments to modifications in cardiomyocyte Ca(2+) handling. Activated in response to fluctuations in cellular Ca(2+) and to various post-translational modifications, CaMKII targets numerous Ca(2+) channels/transporters involved in Ca(2+) handling and contractile function regulation. CaMKII is activated early in reperfusion, where it exacerbates Ca(2+) leak from the sarcoplasmic reticulum and promotes the onset of ventricular arrhythmias. Inhibiting CaMKII can increase functional recovery in reperfusion and reduce apoptotic/necrotic death, at least partly through indirect and direct influences on mitochondrial Ca(2+) levels and function. Yet, CaMKII can also have beneficial actions in ischaemia and reperfusion, in part by providing inotropic support for the stunned myocardium and contributing as an intermediate to cardioprotective preconditioning signalling cascades. There is considerable potential in targeting CaMKII as a part of a surgical reperfusion strategy, though further mechanistic understanding of the relationship between CaMKII activation status and the extent of ischaemia/reperfusion injury are required to fully establish an optimal pharmacological approach.
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Affiliation(s)
- James R Bell
- Department of Physiology, University of Melbourne, Melbourne, Vic., Australia
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37
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Delgado C, Ruiz-Hurtado G, Gómez-Hurtado N, González-Ramos S, Rueda A, Benito G, Prieto P, Zaragoza C, Delicado EG, Pérez-Sen R, Miras-Portugal MT, Núñez G, Boscá L, Fernández-Velasco M. NOD1, a new player in cardiac function and calcium handling. Cardiovasc Res 2015; 106:375-86. [PMID: 25824149 DOI: 10.1093/cvr/cvv118] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Accepted: 03/05/2015] [Indexed: 02/07/2023] Open
Abstract
AIMS Inflammation is a significant contributor to cardiovascular disease and its complications; however, whether the myocardial inflammatory response is harmonized after cardiac injury remains to be determined. Some receptors of the innate immune system, including the nucleotide-binding oligomerization domain-like receptors (NLRs), play key roles in the host response after cardiac damage. Nucleotide-binding oligomerization domain containing 1 (NOD1), a member of the NLR family, is expressed in the heart, but its functional role has not been elucidated. We determine whether selective NOD1 activation modulates cardiac function and Ca(2+) signalling. METHODS AND RESULTS Mice were treated for 3 days with the selective NOD1 agonist C12-iE-DAP (iE-DAP), and cardiac function and Ca(2+) cycling were assessed. We found that iE-DAP treatment resulted in cardiac dysfunction, measured as a decrease in ejection fraction and fractional shortening. Cardiomyocytes isolated from iE-DAP-treated mice displayed a decrease in the L-type Ca(2+) current, [Ca(2+)]i transients and Ca(2+) load, and decreased expression of phospho-phospholamban, sarcoplasmic reticulum-ATPase, and Na(+)-Ca(2+) exchanger. Furthermore, iE-DAP prompted 'diastolic Ca(2+) leak' in cardiomyocytes, resulting from increased Ca(2+) spark frequency and RyR2 over-phosphorylation. Importantly, these iE-DAP-induced changes in Ca(2+) cycling were lost in NOD1(-/-) mice, indicating that iE-DAP exerts its actions through NOD1. Co-treatment of mice with iE-DAP and a selective inhibitor of NF-κB (BAY11-7082) prevented cardiac dysfunction and Ca(2+) handling impairment induced by iE-DAP. CONCLUSION Our data provide the first evidence that NOD1 activation induces cardiac dysfunction associated with excitation-contraction coupling impairment through NF-κB activation and uncover a new pro-inflammatory player in the regulation of cardiovascular function.
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MESH Headings
- Animals
- Anti-Inflammatory Agents/pharmacology
- Calcium/metabolism
- Calcium Channels, L-Type/metabolism
- Calcium-Binding Proteins/metabolism
- Cells, Cultured
- Excitation Contraction Coupling/drug effects
- Inflammation Mediators/agonists
- Inflammation Mediators/antagonists & inhibitors
- Inflammation Mediators/metabolism
- Male
- Membrane Potentials
- Mice, Inbred C57BL
- Mice, Knockout
- Myocardial Contraction/drug effects
- Myocytes, Cardiac/drug effects
- Myocytes, Cardiac/metabolism
- NF-kappa B/metabolism
- Nod1 Signaling Adaptor Protein/agonists
- Nod1 Signaling Adaptor Protein/antagonists & inhibitors
- Nod1 Signaling Adaptor Protein/deficiency
- Nod1 Signaling Adaptor Protein/genetics
- Nod1 Signaling Adaptor Protein/metabolism
- Phosphorylation
- Sarcoplasmic Reticulum Calcium-Transporting ATPases/metabolism
- Sodium-Calcium Exchanger/metabolism
- Stroke Volume
- Ventricular Dysfunction, Left/genetics
- Ventricular Dysfunction, Left/metabolism
- Ventricular Dysfunction, Left/physiopathology
- Ventricular Dysfunction, Left/prevention & control
- Ventricular Function, Left/drug effects
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Affiliation(s)
- Carmen Delgado
- Departamento de Farmacología, Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain Instituto de Investigaciones Biomédicas Alberto Sols, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Gema Ruiz-Hurtado
- Instituto de Investigación i + 12 Hospital Universitario 12 de Octubre and Instituto Pluridisciplinar, UCM, Madrid, Spain
| | - Nieves Gómez-Hurtado
- Departamento de Farmacología, Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain
| | - Silvia González-Ramos
- Instituto de Investigaciones Biomédicas Alberto Sols, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | | | - Gemma Benito
- Instituto de Investigación Hospital Universitario La PAZ, IDIPAZ, Madrid, Spain
| | - Patricia Prieto
- Instituto de Investigaciones Biomédicas Alberto Sols, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Carlos Zaragoza
- Department of Cardiology, University Hospital Ramón y Cajal/University Francisco de Vitoria, Madrid, Spain
| | - Esmerilda G Delicado
- Departamento de Bioquímica y Biología Molecular IV, Facultad de Veterinaria e Instituto Universitario de Investigación en Neuroquímica, Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), Universidad Complutense, Madrid, Spain
| | - Raquel Pérez-Sen
- Departamento de Bioquímica y Biología Molecular IV, Facultad de Veterinaria e Instituto Universitario de Investigación en Neuroquímica, Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), Universidad Complutense, Madrid, Spain
| | - Maria Teresa Miras-Portugal
- Departamento de Bioquímica y Biología Molecular IV, Facultad de Veterinaria e Instituto Universitario de Investigación en Neuroquímica, Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), Universidad Complutense, Madrid, Spain
| | - Gabriel Núñez
- Department of Pathology and Comprehensive Cancer Center, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Lisardo Boscá
- Instituto de Investigaciones Biomédicas Alberto Sols, Consejo Superior de Investigaciones Científicas, Madrid, Spain
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Doleschal B, Primessnig U, Wölkart G, Wolf S, Schernthaner M, Lichtenegger M, Glasnov TN, Kappe CO, Mayer B, Antoons G, Heinzel F, Poteser M, Groschner K. TRPC3 contributes to regulation of cardiac contractility and arrhythmogenesis by dynamic interaction with NCX1. Cardiovasc Res 2015; 106:163-73. [PMID: 25631581 PMCID: PMC4362401 DOI: 10.1093/cvr/cvv022] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Aim TRPC3 is a non-selective cation channel, which forms a Ca2+ entry pathway involved in cardiac remodelling. Our aim was to analyse acute electrophysiological and contractile consequences of TRPC3 activation in the heart. Methods and results We used a murine model of cardiac TRPC3 overexpression and a novel TRPC3 agonist, GSK1702934A, to uncover (patho)physiological functions of TRPC3. GSK1702934A induced a transient, non-selective conductance and prolonged action potentials in TRPC3-overexpressing myocytes but lacked significant electrophysiological effects in wild-type myocytes. GSK1702934A transiently enhanced contractility and evoked arrhythmias in isolated Langendorff hearts from TRPC3-overexpressing but not wild-type mice. Interestingly, pro-arrhythmic effects outlasted TRPC3 current activation, were prevented by enhanced intracellular Ca2+ buffering, and suppressed by the NCX inhibitor 3′,4′-dichlorobenzamil hydrochloride. GSK1702934A substantially promoted NCX currents in TRPC3-overexpressing myocytes. The TRPC3-dependent electrophysiologic, pro-arrhythmic, and inotropic actions of GSK1702934A were mimicked by angiotensin II (AngII). Immunocytochemistry demonstrated colocalization of TRPC3 with NCX1 and disruption of local interaction upon channel activation by either GSK1702934A or AngII. Conclusion Cardiac TRPC3 mediates Ca2+ and Na+ entry in proximity of NCX1, thereby elevating cellular Ca2+ levels and contractility. Excessive activation of TRPC3 is associated with transient cellular Ca2+ overload, spatial uncoupling between TRPC3 and NCX1, and arrhythmogenesis. We propose TRPC3-NCX micro/nanodomain communication as determinant of cardiac contractility and susceptibility to arrhythmogenic stimuli.
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Affiliation(s)
| | - Uwe Primessnig
- Department of Cardiology, Medical University of Graz, Graz, Austria Ludwig Boltzmann Institute of Translational Heart Failure Research, Graz, Austria
| | - Gerald Wölkart
- Institute of Pharmaceutical Sciences, University of Graz, Graz, Austria
| | - Stefan Wolf
- Institute of Pharmaceutical Sciences, University of Graz, Graz, Austria
| | - Michaela Schernthaner
- Institute of Biophysics, Medical University of Graz, Harrachgasse 21, Graz 8010, Austria
| | | | - Toma N Glasnov
- Institute of Chemistry, University of Graz, Graz, Austria Christian Doppler Laboratory for Continuous Flow Chemistry, Institute of Chemistry, University of Graz, Graz, Austria
| | - C Oliver Kappe
- Institute of Chemistry, University of Graz, Graz, Austria
| | - Bernd Mayer
- Institute of Pharmaceutical Sciences, University of Graz, Graz, Austria
| | - Gudrun Antoons
- Department of Cardiology, Medical University of Graz, Graz, Austria Ludwig Boltzmann Institute of Translational Heart Failure Research, Graz, Austria
| | - Frank Heinzel
- Department of Cardiology, Medical University of Graz, Graz, Austria Ludwig Boltzmann Institute of Translational Heart Failure Research, Graz, Austria
| | - Michael Poteser
- Institute of Biophysics, Medical University of Graz, Harrachgasse 21, Graz 8010, Austria
| | - Klaus Groschner
- Ludwig Boltzmann Institute of Translational Heart Failure Research, Graz, Austria Institute of Biophysics, Medical University of Graz, Harrachgasse 21, Graz 8010, Austria
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39
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Abstract
Although t-tubules have traditionally been thought to be absent in atrial cardiomyocytes, recent studies have suggested that t-tubules exist in the atria of large mammals. However, it is unclear whether regional differences in t-tubule organization exist that define cardiomyocyte function across the atria. We sought to investigate regional t-tubule density in pig and rat atria and the consequences for cardiomyocyte Ca(2+) homeostasis. We observed t-tubules in approximately one-third of rat atrial cardiomyocytes, in both tissue cryosections and isolated cardiomyocytes. In a minority (≈10%) of atrial cardiomyocytes, the t-tubular network was well organized, with a transverse structure resembling that of ventricular cardiomyocytes. In both rat and pig atrial tissue, we observed higher t-tubule density in the epicardium than in the endocardium. Consistent with high variability in the distribution of t-tubules and Ca(2+) channels among cells, L-type Ca(2+) current amplitude was also highly variable and steeply dependent on capacitance and t-tubule density. Accordingly, Ca(2+) transients showed great variability in Ca(2+) release synchrony. Simultaneous imaging of the cell membrane and Ca(2+) transients confirmed t-tubule functionality. Results from mathematical modeling indicated that a transmural gradient in t-tubule organization and Ca(2+) release kinetics supports synchronization of contraction across the atrial wall and may underlie transmural differences in the refractory period. In conclusion, our results indicate that t-tubule density is highly variable across the atria. We propose that higher t-tubule density in cells localized in the epicardium may promote synchronization of contraction across the atrial wall.
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Affiliation(s)
- Michael Frisk
- Institute for Experimental Medical Research, Oslo University Hospital and University of Oslo, Oslo, Norway; KG Jebsen Cardiac Research Center and Center for Heart Failure Research, University of Oslo, Oslo, Norway;
| | - Jussi T Koivumäki
- Center for Biomedical Computing, Simula Research Laboratory, Oslo, Norway; and Center for Cardiological Innovation, Oslo University Hospital, Oslo, Norway
| | - Per A Norseng
- Institute for Experimental Medical Research, Oslo University Hospital and University of Oslo, Oslo, Norway; KG Jebsen Cardiac Research Center and Center for Heart Failure Research, University of Oslo, Oslo, Norway
| | - Mary M Maleckar
- Center for Biomedical Computing, Simula Research Laboratory, Oslo, Norway; and Center for Cardiological Innovation, Oslo University Hospital, Oslo, Norway
| | - Ole M Sejersted
- Institute for Experimental Medical Research, Oslo University Hospital and University of Oslo, Oslo, Norway; KG Jebsen Cardiac Research Center and Center for Heart Failure Research, University of Oslo, Oslo, Norway
| | - William E Louch
- Institute for Experimental Medical Research, Oslo University Hospital and University of Oslo, Oslo, Norway; KG Jebsen Cardiac Research Center and Center for Heart Failure Research, University of Oslo, Oslo, Norway
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40
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Bell JR, Vila-Petroff M, Delbridge LMD. CaMKII-dependent responses to ischemia and reperfusion challenges in the heart. Front Pharmacol 2014; 5:96. [PMID: 24834054 PMCID: PMC4018566 DOI: 10.3389/fphar.2014.00096] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Accepted: 04/16/2014] [Indexed: 12/04/2022] Open
Abstract
Ischemic heart disease is a leading cause of death, and there is considerable imperative to identify effective therapeutic interventions. Cardiomyocyte Ca2+ overload is a major cause of ischemia and reperfusion injury, initiating a cascade of events culminating in cardiomyocyte death, myocardial dysfunction, and occurrence of lethal arrhythmias. Responsive to fluctuations in intracellular Ca2+, Ca2+/calmodulin-dependent protein kinase II (CaMKII) has emerged as an enticing therapeutic target in the management of ischemic heart injury. CaMKII is activated early in ischemia and to a greater extent in the first few minutes of reperfusion, at a time when reperfusion arrhythmias are particularly prominent. CaMKII phosphorylates and upregulates many of the key proteins involved in intracellular Na+ and Ca2+ loading in ischemia and reperfusion. Experimentally, selective inhibition of CaMKII activity reduces cardiomyocyte death and arrhythmic incidence post-ischemia. New evidence is emerging that CaMKII actions in ischemia and reperfusion involve specific splice variant targeted actions, selective and localized post-translational modifications, and organelle-directed substrate interactions. A more complete mechanistic understanding of CaMKII mode of action in ischemia and reperfusion is required to optimize intervention opportunities. This review summarizes the current experimentally derived understanding of CaMKII participation in mediating the pathophysiology of the heart in ischemia and in reperfusion, and highlights priority future research directions.
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Affiliation(s)
- James R Bell
- Department of Physiology, University of Melbourne Melbourne, VIC, Australia
| | - Martin Vila-Petroff
- Centro de Investigaciones Cardiovasculares, Centro Científico Tecnológico La Plata, Facultad de Ciencias Médicas, Universidad Nacional de La Plata La Plata, Argentina
| | - Lea M D Delbridge
- Department of Physiology, University of Melbourne Melbourne, VIC, Australia
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