1
|
Klocke B, Britzolaki A, Saurine J, Ott H, Krone K, Bahamonde K, Thelen C, Tzimas C, Sanoudou D, Kranias EG, Pitychoutis PM. A novel role for phospholamban in the thalamic reticular nucleus. Sci Rep 2024; 14:6376. [PMID: 38493225 PMCID: PMC10944534 DOI: 10.1038/s41598-024-56447-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Accepted: 03/06/2024] [Indexed: 03/18/2024] Open
Abstract
The thalamic reticular nucleus (TRN) is a brain region that influences vital neurobehavioral processes, including executive functioning and the generation of sleep rhythms. TRN dysfunction underlies hyperactivity, attention deficits, and sleep disturbances observed across various neurodevelopmental disorders. A specialized sarco-endoplasmic reticulum calcium (Ca2+) ATPase 2 (SERCA2)-dependent Ca2+ signaling network operates in the dendrites of TRN neurons to regulate their bursting activity. Phospholamban (PLN) is a prominent regulator of SERCA2 with an established role in myocardial Ca2+-cycling. Our findings suggest that the role of PLN extends beyond the cardiovascular system to impact brain function. Specifically, we found PLN to be expressed in TRN neurons of the adult mouse brain, and utilized global constitutive and innovative conditional genetic knockout mouse models in concert with electroencephalography (EEG)-based somnography and the 5-choice serial reaction time task (5-CSRTT) to investigate the role of PLN in sleep and executive functioning, two complex behaviors that map onto thalamic reticular circuits. The results of the present study indicate that perturbed PLN function in the TRN results in aberrant TRN-dependent phenotypes in mice (i.e., hyperactivity, impulsivity and sleep deficits) and support a novel role for PLN as a critical regulator of SERCA2 in the TRN neurocircuitry.
Collapse
Affiliation(s)
- Benjamin Klocke
- Department of Biology, University of Dayton, 300 College Park, Dayton, OH, 45469-2320, USA
| | - Aikaterini Britzolaki
- Department of Biology, University of Dayton, 300 College Park, Dayton, OH, 45469-2320, USA
| | - Joseph Saurine
- Department of Biology, University of Dayton, 300 College Park, Dayton, OH, 45469-2320, USA
| | - Hayden Ott
- Department of Biology, University of Dayton, 300 College Park, Dayton, OH, 45469-2320, USA
| | - Kylie Krone
- Department of Biology, University of Dayton, 300 College Park, Dayton, OH, 45469-2320, USA
| | - Kiara Bahamonde
- Department of Biology, University of Dayton, 300 College Park, Dayton, OH, 45469-2320, USA
| | - Connor Thelen
- Department of Biology, University of Dayton, 300 College Park, Dayton, OH, 45469-2320, USA
| | - Christos Tzimas
- Molecular Biology Department, Biomedical Research Foundation of the Academy of Athens, 11527, Athens, Greece
| | - Despina Sanoudou
- Molecular Biology Department, Biomedical Research Foundation of the Academy of Athens, 11527, Athens, Greece
- 4th Department of Internal Medicine, Clinical Genomics and Pharmacogenomics Unit, Medical School, "Attikon" Hospital, National and Kapodistrian University of Athens, 11527, Athens, Greece
| | - Evangelia G Kranias
- Molecular Biology Department, Biomedical Research Foundation of the Academy of Athens, 11527, Athens, Greece
- Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, OH, 45267, USA
| | - Pothitos M Pitychoutis
- Department of Biology, University of Dayton, 300 College Park, Dayton, OH, 45469-2320, USA.
| |
Collapse
|
2
|
Mattiazzi A, Kranias EG. Unleashing the Power of Genetics: PLN Ablation, Phospholambanopathies and Evolving Challenges. Circ Res 2024; 134:138-142. [PMID: 38236951 DOI: 10.1161/circresaha.123.323053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2024]
Affiliation(s)
- Alicia Mattiazzi
- Centro de Investigaciones Cardiovasculares, Centro Cientifico Tecnologico-La Plata CONICET (Consejo Nacional de Investigaciones Científicas y Técnicas), Facultad de Ciencias Médicas, Universidad Nacional de La Plata, Argentina (A.M.)
| | - Evangelia G Kranias
- Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, OH (E.G.K.)
| |
Collapse
|
3
|
Klocke B, Britzolaki A, Saurine J, Ott H, Krone K, Bahamonde K, Thelen C, Tzimas C, Sanoudou D, Kranias EG, Pitychoutis PM. A Novel Role for Phospholamban in the Thalamic Reticular Nucleus. bioRxiv 2023:2023.11.22.568306. [PMID: 38045420 PMCID: PMC10690257 DOI: 10.1101/2023.11.22.568306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
The thalamic reticular nucleus (TRN) is a critical brain region that greatly influences vital neurobehavioral processes, including executive functioning and the generation of sleep rhythms. Recently, TRN dysfunction was suggested to underlie hyperactivity, attention deficits, and sleep disturbances observed across various devastating neurodevelopmental disorders, including autism, schizophrenia and attention-deficit/hyperactivity disorder (ADHD). Notably, a highly specialized sarco- endoplasmic reticulum calcium (Ca 2+ ) ATPase 2 (SERCA2)-dependent Ca 2+ signaling network operates in the dendrites of TRN neurons to regulate their high-frequency bursting activity. Phospholamban (PLN) is a prominent regulator of the SERCA2 with an established role in maintaining Ca 2+ homeostasis in the heart; although the interaction of PLN with SERCA2 has been largely regarded as cardiac-specific, our findings challenge this view and suggest that the role of PLN extends beyond the cardiovascular system to impact brain function. Specifically, we found PLN to be expressed in the TRN neurons of the adult mouse brain and utilized global constitutive and innovative conditional genetic mouse models, in combination with 5-choice serial reaction time task (5-CSRTT) and electroencephalography (EEG)-based somnography to assess the role of PLN in regulating executive functioning and sleep, two complex behaviors that map onto thalamic reticular circuits. Overall, the results of the present study show that perturbed PLN function in the TRN results in aberrant thalamic reticular behavioral phenotypes in mice (i.e., hyperactivity, impulsivity and sleep deficits) and support a novel role for PLN as a critical regulator of the SERCA2 in the thalamic reticular neurocircuitry.
Collapse
|
4
|
Kumar M, Haghighi K, Koch S, Rubinstein J, Stillitano F, Hajjar RJ, Kranias EG, Sadayappan S. Myofilament Alterations Associated with Human R14del-Phospholamban Cardiomyopathy. Int J Mol Sci 2023; 24:2675. [PMID: 36768995 PMCID: PMC9917359 DOI: 10.3390/ijms24032675] [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] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 01/23/2023] [Accepted: 01/27/2023] [Indexed: 02/01/2023] Open
Abstract
Phospholamban (PLN) is a major regulator of cardiac contractility, and human mutations in this gene give rise to inherited cardiomyopathies. The deletion of Arginine 14 is the most-prevalent cardiomyopathy-related mutation, and it has been linked to arrhythmogenesis and early death. Studies in PLN-humanized mutant mice indicated an increased propensity to arrhythmias, but the underlying cellular mechanisms associated with R14del-PLN cardiac dysfunction in the absence of any apparent structural remodeling remain unclear. The present study addressed the specific role of myofilaments in the setting of R14del-PLN and the long-term effects of R14del-PLN in the heart. Maximal force was depressed in skinned cardiomyocytes from both left and right ventricles, but this effect was more pronounced in the right ventricle of R14del-PLN mice. In addition, the Ca2+ sensitivity of myofilaments was increased in both ventricles of mutant mice. However, the depressive effects of R14del-PLN on contractile parameters could be reversed with the positive inotropic drug omecamtiv mecarbil, a myosin activator. At 12 months of age, corresponding to the mean symptomatic age of R14del-PLN patients, contractile parameters and Ca2+ transients were significantly depressed in the right ventricular R14del-PLN cardiomyocytes. Echocardiography did not reveal any alterations in cardiac function or remodeling, although histological and electron microscopy analyses indicated subtle alterations in mutant hearts. These findings suggest that both aberrant myocyte calcium cycling and aberrant contractility remain specific to the right ventricle in the long term. In addition, altered myofilament activity is an early characteristic of R14del-PLN mutant hearts and the positive inotropic drug omecamtiv mecarbil may be beneficial in treating R14del-PLN cardiomyopathy.
Collapse
Affiliation(s)
- Mohit Kumar
- Department of Medicine, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
| | - Kobra Haghighi
- Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
| | - Sheryl Koch
- Department of Medicine, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
| | - Jack Rubinstein
- Department of Medicine, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
| | - Francesca Stillitano
- Division Heart and Lung, Department of Cardiology, University Medical Center Utrecht, 3584 CX Utrecht, The Netherlands
| | - Roger J. Hajjar
- Phospholamban Heart Foundation, Postbus 66, 1775 ZH Middenmeer, The Netherlands
| | - Evangelia G. Kranias
- Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
| | - Sakthivel Sadayappan
- Department of Medicine, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
| |
Collapse
|
5
|
Vafiadaki E, Glijnis PC, Doevendans PA, Kranias EG, Sanoudou D. Phospholamban R14del disease: The past, the present and the future. Front Cardiovasc Med 2023; 10:1162205. [PMID: 37144056 PMCID: PMC10151546 DOI: 10.3389/fcvm.2023.1162205] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Accepted: 04/03/2023] [Indexed: 05/06/2023] Open
Abstract
Arrhythmogenic cardiomyopathy affects significant number of patients worldwide and is characterized by life-threatening ventricular arrhythmias and sudden cardiac death. Mutations in multiple genes with diverse functions have been reported to date including phospholamban (PLN), a key regulator of sarcoplasmic reticulum (SR) Ca2+ homeostasis and cardiac contractility. The PLN-R14del variant in specific is recognized as the cause in an increasing number of patients worldwide, and extensive investigations have enabled rapid advances towards the delineation of PLN-R14del disease pathogenesis and discovery of an effective treatment. We provide a critical overview of current knowledge on PLN-R14del disease pathophysiology, including clinical, animal model, cellular and biochemical studies, as well as diverse therapeutic approaches that are being pursued. The milestones achieved in <20 years, since the discovery of the PLN R14del mutation (2006), serve as a paradigm of international scientific collaboration and patient involvement towards finding a cure.
Collapse
Affiliation(s)
- Elizabeth Vafiadaki
- Center of Basic Research, Biomedical Research Foundation of the Academy of Athens, Athens, Greece
- Correspondence: Elizabeth Vafiadaki Despina Sanoudou
| | - Pieter C. Glijnis
- Stichting Genetische Hartspierziekte PLN, Phospholamban Foundation, Wieringerwerf, Netherlands
| | - Pieter A. Doevendans
- Netherlands Heart Institute, Utrecht, Netherlands
- Department of Cardiology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Evangelia G. Kranias
- Center of Basic Research, Biomedical Research Foundation of the Academy of Athens, Athens, Greece
- Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, OH, United States
| | - Despina Sanoudou
- Center of Basic Research, Biomedical Research Foundation of the Academy of Athens, Athens, Greece
- Clinical Genomics and Pharmacogenomics Unit, 4th Department of Internal Medicine, Attikon Hospital, Medical School, National and Kapodistrian University of Athens, Athens, Greece
- Center for New Biotechnologies and Precision Medicine, Medical School, National and Kapodistrian University of Athens, Athens, Greece
- Correspondence: Elizabeth Vafiadaki Despina Sanoudou
| |
Collapse
|
6
|
Rogalska ME, Vafiadaki E, Erpapazoglou Z, Haghighi K, Green L, Mantzoros CS, Hajjar RJ, Tranter M, Karakikes I, Kranias EG, Stillitano F, Kafasla P, Sanoudou D. Isoform changes of action potential regulators in the ventricles of arrhythmogenic phospholamban-R14del humanized mouse hearts. Metabolism 2023; 138:155344. [PMID: 36375644 DOI: 10.1016/j.metabol.2022.155344] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [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: 07/06/2022] [Revised: 10/30/2022] [Accepted: 11/01/2022] [Indexed: 11/13/2022]
Abstract
Arrhythmogenic cardiomyopathy (ACM) is characterized by life-threatening ventricular arrhythmias and sudden cardiac death and affects hundreds of thousands of patients worldwide. The deletion of Arginine 14 (p.R14del) in the phospholamban (PLN) gene has been implicated in the pathogenesis of ACM. PLN is a key regulator of sarcoplasmic reticulum (SR) Ca2+ cycling and cardiac contractility. Despite global gene and protein expression studies, the molecular mechanisms of PLN-R14del ACM pathogenesis remain unclear. Using a humanized PLN-R14del mouse model and human induced pluripotent stem cell derived cardiomyocytes (iPSC-CMs), we investigated the transcriptome-wide mRNA splicing changes associated with the R14del mutation. We identified >200 significant alternative splicing (AS) events and distinct AS profiles were observed in the right (RV) and left (LV) ventricles in PLN-R14del compared to WT mouse hearts. Enrichment analysis of the AS events showed that the most affected biological process was associated with "cardiac cell action potential", specifically in the RV. We found that splicing of 2 key genes, Trpm4 and Camk2d, which encode proteins regulating calcium homeostasis in the heart, were altered in PLN-R14del mouse hearts and human iPSC-CMs. Bioinformatical analysis pointed to the tissue-specific splicing factors Srrm4 and Nova1 as likely upstream regulators of the observed splicing changes in the PLN-R14del cardiomyocytes. Our findings suggest that aberrant splicing may affect Ca2+-homeostasis in the heart, contributing to the increased risk of arrythmogenesis in PLN-R14del ACM.
Collapse
Affiliation(s)
- Malgorzata E Rogalska
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona 08003, Spain
| | - Elizabeth Vafiadaki
- Molecular Biology Division, Biomedical Research Foundation of the Academy of Athens, 11527 Athens, Greece
| | - Zoi Erpapazoglou
- Institute for Fundamental Biomedical Research, B.S.R.C. "Alexander Fleming", 16672 Athens, Greece
| | - Kobra Haghighi
- Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
| | - Lisa Green
- Department of Medicine, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
| | - Christos S Mantzoros
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA; Section of Endocrinology, Boston VA Healthcare System, Harvard Medical School, Boston, MA 02215, USA
| | | | - Michael Tranter
- Department of Medicine, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
| | - Ioannis Karakikes
- Department of Cardiothoracic Surgery and Cardiovascular Institute, Stanford University School of Medicine, 240 Pasteur Dr, Stanford, CA 94304, USA
| | - Evangelia G Kranias
- Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
| | - Francesca Stillitano
- Division Heart and Lung, Department of Cardiology, University Medical Center Utrecht, 3584, CX, Utrecht, the Netherlands
| | - Panagiota Kafasla
- Institute for Fundamental Biomedical Research, B.S.R.C. "Alexander Fleming", 16672 Athens, Greece
| | - Despina Sanoudou
- Molecular Biology Division, Biomedical Research Foundation of the Academy of Athens, 11527 Athens, Greece; Clinical Genomics and Pharmacogenomics Unit, 4(th) Department of Internal Medicine, Attikon Hospital, Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece; Center for New Biotechnologies and Precision Medicine, Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece.
| |
Collapse
|
7
|
Sadayappan S, Kranias EG. In Memoriam Tribute to Jeffrey Robbins, PhD (1950–2022). Circ Res 2022; 131:870-872. [DOI: 10.1161/circresaha.122.322105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Sakthivel Sadayappan
- Division of Cardiovascular Health and Disease, Department of Internal Medicine, (S.S.), University of Cincinnati College of Medicine, Cincinnati, OH
| | - Evangelia G. Kranias
- Department of Pharmacology and Systems Physiology (E.G.K.), University of Cincinnati College of Medicine, Cincinnati, OH
| |
Collapse
|
8
|
Dave J, Raad N, Mittal N, Zhang L, Fargnoli A, Oh JG, Savoia ME, Hansen J, Fava M, Yin X, Theofilatos K, Ceholski D, Kohlbrenner E, Jeong D, Wills L, Nonnenmacher M, Haghighi K, Costa KD, Turnbull IC, Mayr M, Cai CL, Kranias EG, Akar FG, Hajjar RJ, Stillitano F. Gene editing reverses arrhythmia susceptibility in humanized PLN-R14del mice: modelling a European cardiomyopathy with global impact. Cardiovasc Res 2022; 118:3140-3150. [PMID: 35191471 PMCID: PMC9732517 DOI: 10.1093/cvr/cvac021] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [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: 06/09/2020] [Accepted: 02/18/2022] [Indexed: 12/16/2022] Open
Abstract
AIMS A mutation in the phospholamban (PLN) gene, leading to deletion of Arg14 (R14del), has been associated with malignant arrhythmias and ventricular dilation. Identifying pre-symptomatic carriers with vulnerable myocardium is crucial because arrhythmia can result in sudden cardiac death, especially in young adults with PLN-R14del mutation. This study aimed at assessing the efficiency and efficacy of in vivo genome editing, using CRISPR/Cas9 and a cardiotropic adeno-associated virus-9 (AAV9), in improving cardiac function in young adult mice expressing the human PLN-R14del. METHODS AND RESULTS Humanized mice were generated expressing human wild-type (hPLN-WT) or mutant (hPLN-R14del) PLN in the heterozygous state, mimicking human carriers. Cardiac magnetic resonance imaging at 12 weeks of age showed bi-ventricular dilation and increased stroke volume in mutant vs. WT mice, with no deficit in ejection fraction or cardiac output. Challenge of ex vivo hearts with isoproterenol and rapid pacing unmasked higher propensity for sustained ventricular tachycardia (VT) in hPLN-R14del relative to hPLN-WT. Specifically, the VT threshold was significantly reduced (20.3 ± 1.2 Hz in hPLN-R14del vs. 25.7 ± 1.3 Hz in WT, P < 0.01) reflecting higher arrhythmia burden. To inactivate the R14del allele, mice were tail-vein-injected with AAV9.CRISPR/Cas9/gRNA or AAV9 empty capsid (controls). CRISPR-Cas9 efficiency was evaluated by droplet digital polymerase chain reaction and NGS-based amplicon sequencing. In vivo gene editing significantly reduced end-diastolic and stroke volumes in hPLN-R14del CRISPR-treated mice compared to controls. Susceptibility to VT was also reduced, as the VT threshold was significantly increased relative to controls (30.9 ± 2.3 Hz vs. 21.3 ± 1.5 Hz; P < 0.01). CONCLUSIONS This study is the first to show that disruption of hPLN-R14del allele by AAV9-CRISPR/Cas9 improves cardiac function and reduces VT susceptibility in humanized PLN-R14del mice, offering preclinical evidence for translatable approaches to therapeutically suppress the arrhythmogenic phenotype in human patients with PLN-R14del disease.
Collapse
Affiliation(s)
- Jaydev Dave
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Nour Raad
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Nishka Mittal
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Lu Zhang
- Department of Pediatrics, Riley Heart Research Center, Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Anthony Fargnoli
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Jae Gyun Oh
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | | | - Jens Hansen
- Department of Pharmacological Sciences and Institute for Systems Biomedicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Marika Fava
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Xiaoke Yin
- King’s British Heart Foundation Centre, King’s College London, London, UK
| | | | - Delaine Ceholski
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Erik Kohlbrenner
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Dongtak Jeong
- Department of Molecular & Life Science, College of Science and Convergence Technology, Hanyang University-ERICA, Ansan-si, South Korea
| | - Lauren Wills
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Mathieu Nonnenmacher
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Kobra Haghighi
- Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Kevin D Costa
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Irene C Turnbull
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Manuel Mayr
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, USA,King’s British Heart Foundation Centre, King’s College London, London, UK
| | - Chen-Leng Cai
- Department of Pediatrics, Riley Heart Research Center, Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Evangelia G Kranias
- Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Fadi G Akar
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | | | | |
Collapse
|
9
|
Cely-Ortiz A, Felice JI, Díaz-Zegarra LA, Valverde CA, Federico M, Palomeque J, Wehrens XHT, Kranias EG, Aiello EA, Lascano EC, Negroni JA, Mattiazzi A. Determinants of Ca2+ release restitution: Insights from genetically altered animals and mathematical modeling. J Gen Physiol 2021; 152:152125. [PMID: 32986800 PMCID: PMC7594441 DOI: 10.1085/jgp.201912512] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Revised: 07/27/2020] [Accepted: 08/21/2020] [Indexed: 01/07/2023] Open
Abstract
Each heartbeat is followed by a refractory period. Recovery from refractoriness is known as Ca2+ release restitution (CRR), and its alterations are potential triggers of Ca2+ arrhythmias. Although the control of CRR has been associated with SR Ca2+ load and RYR2 Ca2+ sensitivity, the relative role of some of the determinants of CRR remains largely undefined. An intriguing point, difficult to dissect and previously neglected, is the possible independent effect of SR Ca2+ content versus the velocity of SR Ca2+ refilling on CRR. To assess these interrogations, we used isolated myocytes with phospholamban (PLN) ablation (PLNKO), knock-in mice with pseudoconstitutive CaMKII phosphorylation of RYR2 S2814 (S2814D), S2814D crossed with PLNKO mice (SDKO), and a previously validated human cardiac myocyte model. Restitution of cytosolic Ca2+ (Fura-2 AM) and L-type calcium current (ICaL; patch-clamp) was evaluated with a two-pulse (S1/S2) protocol. CRR and ICaL restitution increased as a function of the (S2-S1) coupling interval, following an exponential curve. When SR Ca2+ load was increased by increasing extracellular [Ca2+] from 2.0 to 4.0 mM, CRR and ICaL restitution were enhanced, suggesting that ICaL restitution may contribute to the faster CRR observed at 4.0 mM [Ca2+]. In contrast, ICaL restitution did not differ among the different mouse models. For a given SR Ca2+ load, CRR was accelerated in S2814D myocytes versus WT, but not in PLNKO and SDKO myocytes versus WT and S2814D, respectively. The model mimics all experimental data. Moreover, when the PLN ablation-induced decrease in RYR2 expression was corrected, the model revealed that CRR was accelerated in PLNKO and SDKO versus WT and S2814D myocytes, consistent with the enhanced velocity of refilling, SR [Ca2+] recovery, and CRR. We speculate that refilling rate might enhance CRR independently of SR Ca2+ load.
Collapse
Affiliation(s)
- Alejandra Cely-Ortiz
- Centro de Investigaciones Cardiovasculares, Centro Científico Tecnológico-La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Juan I Felice
- Centro de Investigaciones Cardiovasculares, Centro Científico Tecnológico-La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Leandro A Díaz-Zegarra
- Centro de Investigaciones Cardiovasculares, Centro Científico Tecnológico-La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Carlos A Valverde
- Centro de Investigaciones Cardiovasculares, Centro Científico Tecnológico-La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Marilén Federico
- Centro de Investigaciones Cardiovasculares, Centro Científico Tecnológico-La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Julieta Palomeque
- Centro de Investigaciones Cardiovasculares, Centro Científico Tecnológico-La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Xander H T Wehrens
- Departments of Molecular Physiology and Biophysics, Medicine (in Cardiology), Neuroscience, Pediatrics, Center for Space Medicine, Baylor College of Medicine, Cardiovascular Research Institute, Houston, TX
| | - Evangelia G Kranias
- Department of Pharmacology, University of Cincinnati College of Medicine, Cincinnati, OH
| | - Ernesto A Aiello
- Centro de Investigaciones Cardiovasculares, Centro Científico Tecnológico-La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Elena C Lascano
- Instituto de Medicina Traslacional, Trasplante y Bioingeniería, Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad Favaloro, Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| | - Jorge A Negroni
- Instituto de Medicina Traslacional, Trasplante y Bioingeniería, Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad Favaloro, Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| | - Alicia Mattiazzi
- Centro de Investigaciones Cardiovasculares, Centro Científico Tecnológico-La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina
| |
Collapse
|
10
|
Raad N, Bittihn P, Cacheux M, Jeong D, Ilkan Z, Ceholski D, Kohlbrenner E, Zhang L, Cai CL, Kranias EG, Hajjar RJ, Stillitano F, Akar FG. Arrhythmia Mechanism and Dynamics in a Humanized Mouse Model of Inherited Cardiomyopathy Caused by Phospholamban R14del Mutation. Circulation 2021; 144:441-454. [PMID: 34024116 DOI: 10.1161/circulationaha.119.043502] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND Arginine (Arg) 14 deletion (R14del) in the calcium regulatory protein phospholamban (hPLNR14del) has been identified as a disease-causing mutation in patients with an inherited cardiomyopathy. Mechanisms underlying the early arrhythmogenic phenotype that predisposes carriers of this mutation to sudden death with no apparent structural remodeling remain unclear. METHODS To address this, we performed high spatiotemporal resolution optical mapping of intact hearts from adult knock-in mice harboring the human PLNWT (wildtype [WT], n=12) or the heterozygous human PLNR14del mutation (R14del, n=12) before and after ex vivo challenge with isoproterenol and rapid pacing. RESULTS Adverse electrophysiological remodeling was evident in the absence of significant structural or hemodynamic changes. R14del hearts exhibited increased arrhythmia susceptibility compared with wildtype. Underlying this susceptibility was preferential right ventricular action potential prolongation that was unresponsive to β-adrenergic stimulation. A steep repolarization gradient at the left ventricular/right ventricular interface provided the substrate for interventricular activation delays and ultimately local conduction block during rapid pacing. This was followed by the initiation of macroreentrant circuits supporting the onset of ventricular tachycardia. Once sustained, these circuits evolved into high-frequency rotors, which in their majority were pinned to the right ventricle. These rotors exhibited unique spatiotemporal dynamics that promoted their increased stability in R14del compared with wildtype hearts. CONCLUSIONS Our findings highlight the crucial role of primary electric remodeling caused by the hPLNR14del mutation. These inherently arrhythmogenic features form the substrate for adrenergic-mediated VT at early stages of PLNR14del induced cardiomyopathy.
Collapse
Affiliation(s)
- Nour Raad
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY (N.R., M.C., D.J., Z.I., D.C., E.K., F.S., F.G.A.).,Poliklinik für Innere Medizin I, Rechts der Isar Hospital, Technical University Munich, Germany (N.R.).,German Center for Cardiovascular Research, Munich Heart Alliance (N.R.)
| | - Philip Bittihn
- BioCircuits Institute, University of California, San Diego (P.B.).,Max Planck Institute for Dynamics and Self-Organization, Göttingen, Germany (P.B.)
| | - Marine Cacheux
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY (N.R., M.C., D.J., Z.I., D.C., E.K., F.S., F.G.A.)
| | - Dongtak Jeong
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY (N.R., M.C., D.J., Z.I., D.C., E.K., F.S., F.G.A.)
| | - Zeki Ilkan
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY (N.R., M.C., D.J., Z.I., D.C., E.K., F.S., F.G.A.)
| | - Delaine Ceholski
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY (N.R., M.C., D.J., Z.I., D.C., E.K., F.S., F.G.A.)
| | - Erik Kohlbrenner
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY (N.R., M.C., D.J., Z.I., D.C., E.K., F.S., F.G.A.)
| | - Lu Zhang
- Indiana University School of Medicine, Indianapolis (L.Z., C.C.)
| | - Chen-Leng Cai
- Indiana University School of Medicine, Indianapolis (L.Z., C.C.)
| | | | - Roger J Hajjar
- Phospholamban Foundation, Middenmeer, The Netherlands (R.J.H.)
| | - Francesca Stillitano
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY (N.R., M.C., D.J., Z.I., D.C., E.K., F.S., F.G.A.)
| | - Fadi G Akar
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY (N.R., M.C., D.J., Z.I., D.C., E.K., F.S., F.G.A.).,School of Medicine (F.G.A.), Yale University, New Haven, CT.,Department of Biomedical Engineering (F.G.A.). Yale University, New Haven, CT
| |
Collapse
|
11
|
Affiliation(s)
- Alicia Mattiazzi
- Centro de Investigaciones Cardiovasculares, CCT-La Plata-CONICET, Facultad de Medicina, UNLP, La Plata, Argentina (A.M.)
| | - Jil C Tardiff
- Department of Biomedical Engineering and Medicine, University of Arizona, Tucson (J.C.T.)
| | - Evangelia G Kranias
- Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, OH (E.G.K.)
| |
Collapse
|
12
|
Arif M, Nabavizadeh P, Song T, Desai D, Singh R, Bazrafshan S, Kumar M, Wang Y, Gilbert RJ, Dhandapany PS, Becker RC, Kranias EG, Sadayappan S. Genetic, clinical, molecular, and pathogenic aspects of the South Asian-specific polymorphic MYBPC3 Δ25bp variant. Biophys Rev 2020; 12:1065-1084. [PMID: 32656747 PMCID: PMC7429610 DOI: 10.1007/s12551-020-00725-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [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: 06/30/2020] [Accepted: 07/03/2020] [Indexed: 02/06/2023] Open
Abstract
Hypertrophic cardiomyopathy (HCM) is a cardiac genetic disease characterized by ventricular enlargement, diastolic dysfunction, and increased risk for sudden cardiac death. Sarcomeric genetic defects are the predominant known cause of HCM. In particular, mutations in the myosin-binding protein C gene (MYBPC3) are associated with ~ 40% of all HCM cases in which a genetic basis has been established. A decade ago, our group reported a 25-base pair deletion in intron 32 of MYBPC3 (MYBPC3Δ25bp) that is uniquely prevalent in South Asians and is associated with autosomal dominant cardiomyopathy. Although our studies suggest that this deletion results in left ventricular dysfunction, cardiomyopathies, and heart failure, the precise mechanism by which this variant predisposes to heart disease remains unclear. Increasingly appreciated, however, is the contribution of secondary risk factors, additional mutations, and lifestyle choices in augmenting or modifying the HCM phenotype in MYBPC3Δ25bp carriers. Therefore, the goal of this review article is to summarize the current research dedicated to understanding the molecular pathophysiology of HCM in South Asians with the MYBPC3Δ25bp variant. An emphasis is to review the latest techniques currently applied to explore the MYBPC3Δ25bp pathogenesis and to provide a foundation for developing new diagnostic strategies and advances in therapeutics.
Collapse
Affiliation(s)
- Mohammed Arif
- Division of Cardiovascular Health and Disease, Department of Internal Medicine, Heart, Lung and Vascular Institute, University of Cincinnati, College of Medicine, 231 Albert Sabin Way, Cincinnati, OH, 45267-0575, USA.
| | - Pooneh Nabavizadeh
- Division of Cardiovascular Health and Disease, Department of Internal Medicine, Heart, Lung and Vascular Institute, University of Cincinnati, College of Medicine, 231 Albert Sabin Way, Cincinnati, OH, 45267-0575, USA
| | - Taejeong Song
- Division of Cardiovascular Health and Disease, Department of Internal Medicine, Heart, Lung and Vascular Institute, University of Cincinnati, College of Medicine, 231 Albert Sabin Way, Cincinnati, OH, 45267-0575, USA
| | - Darshini Desai
- Division of Cardiovascular Health and Disease, Department of Internal Medicine, Heart, Lung and Vascular Institute, University of Cincinnati, College of Medicine, 231 Albert Sabin Way, Cincinnati, OH, 45267-0575, USA
| | - Rohit Singh
- Division of Cardiovascular Health and Disease, Department of Internal Medicine, Heart, Lung and Vascular Institute, University of Cincinnati, College of Medicine, 231 Albert Sabin Way, Cincinnati, OH, 45267-0575, USA
| | - Sholeh Bazrafshan
- Division of Cardiovascular Health and Disease, Department of Internal Medicine, Heart, Lung and Vascular Institute, University of Cincinnati, College of Medicine, 231 Albert Sabin Way, Cincinnati, OH, 45267-0575, USA
| | - Mohit Kumar
- Division of Cardiovascular Health and Disease, Department of Internal Medicine, Heart, Lung and Vascular Institute, University of Cincinnati, College of Medicine, 231 Albert Sabin Way, Cincinnati, OH, 45267-0575, USA
| | - Yigang Wang
- Department of Pathology and Laboratory Medicine, University of Cincinnati, College of Medicine, Cincinnati, OH, 45267, USA
| | - Richard J Gilbert
- Research Service, Providence VA Medical Center, Providence, RI, 02908, USA
| | - Perundurai S Dhandapany
- Centre for Cardiovascular Biology and Disease, Institute for Stem Cell Biology and Regenerative Medicine (inStem), Bangalore, India
- The Knight Cardiovascular Institute, Oregon Health and Science University, Portland, OR, USA
- Department of Medicine, Oregon Health and Science University, Portland, OR, USA
- Department of Molecular and Medical Genetics, Oregon Health and Science University, Portland, OR, USA
| | - Richard C Becker
- Division of Cardiovascular Health and Disease, Department of Internal Medicine, Heart, Lung and Vascular Institute, University of Cincinnati, College of Medicine, 231 Albert Sabin Way, Cincinnati, OH, 45267-0575, USA
| | - Evangelia G Kranias
- Department of Pharmacology and Systems Physiology, University of Cincinnati, College of Medicine, Cincinnati, OH, 45267, USA
| | - Sakthivel Sadayappan
- Division of Cardiovascular Health and Disease, Department of Internal Medicine, Heart, Lung and Vascular Institute, University of Cincinnati, College of Medicine, 231 Albert Sabin Way, Cincinnati, OH, 45267-0575, USA
| |
Collapse
|
13
|
Kumar M, Haghighi K, Kranias EG, Sadayappan S. Phosphorylation of cardiac myosin-binding protein-C contributes to calcium homeostasis. J Biol Chem 2020; 295:11275-11291. [PMID: 32554466 DOI: 10.1074/jbc.ra120.013296] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 06/17/2020] [Indexed: 12/13/2022] Open
Abstract
Cardiac myosin-binding protein-C (cMyBP-C) is highly phosphorylated under basal conditions. However, its phosphorylation level is decreased in individuals with heart failure. The necessity of cMyBP-C phosphorylation for proper contractile function is well-established, but the physiological and pathological consequences of decreased cMyBP-C phosphorylation in the heart are not clear. Herein, using intact adult cardiomyocytes from mouse models expressing phospho-ablated (AAA) and phosphomimetic (DDD) cMyBP-C as well as controls, we found that cMyBP-C dephosphorylation is sufficient to reduce contractile parameters and calcium kinetics associated with prolonged decay time of the calcium transient and increased diastolic calcium levels. Isoproterenol stimulation reversed the depressive contractile and Ca2+-kinetic parameters. Moreover, caffeine-induced calcium release yielded no difference between AAA/DDD and controls in calcium content of the sarcoplasmic reticulum. On the other hand, sodium-calcium exchanger function and phosphorylation levels of calcium-handling proteins were significantly decreased in AAA hearts compared with controls. Stress conditions caused increases in both spontaneous aftercontractions in AAA cardiomyocytes and the incidence of arrhythmias in vivo compared with the controls. Treatment with omecamtiv mecarbil, a positive cardiac inotropic drug, rescued the contractile deficit in AAA cardiomyocytes, but not the calcium-handling abnormalities. These findings indicate a cascade effect whereby cMyBP-C dephosphorylation causes contractile defects, which then lead to calcium-cycling abnormalities, resulting in aftercontractions and increased incidence of cardiac arrhythmias under stress conditions. We conclude that improvement of contractile deficits alone without improving calcium handling may be insufficient for effective management of heart failure.
Collapse
Affiliation(s)
- Mohit Kumar
- Heart, Lung, and Vascular Institute, Division of Cardiovascular Health and Disease, Department of Internal Medicine, University of Cincinnati, Cincinnati, Ohio, USA.,Department of Pharmacology and Systems Physiology, University of Cincinnati, Cincinnati, Ohio, USA
| | - Kobra Haghighi
- Department of Pharmacology and Systems Physiology, University of Cincinnati, Cincinnati, Ohio, USA
| | - Evangelia G Kranias
- Department of Pharmacology and Systems Physiology, University of Cincinnati, Cincinnati, Ohio, USA
| | - Sakthivel Sadayappan
- Heart, Lung, and Vascular Institute, Division of Cardiovascular Health and Disease, Department of Internal Medicine, University of Cincinnati, Cincinnati, Ohio, USA .,Department of Pharmacology and Systems Physiology, University of Cincinnati, Cincinnati, Ohio, USA
| |
Collapse
|
14
|
Meli AC, Kranias EG. Scientists on the Spot: Calcium dynamics in heart function. Cardiovasc Res 2020; 116:e73-e74. [PMID: 32176278 DOI: 10.1093/cvr/cvaa031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Albano C Meli
- PhyMedExp, Inserm, University of Montpellier, CNRS, Montpellier, France
| | - Evangelia G Kranias
- Department of Pharmacology and Systems Physiology, University of Cincinnati Medical Center, 231 Albert B. Sabin Way, Cincinnati, OH 45267-0575, USA
| |
Collapse
|
15
|
Valverde CA, Mazzocchi G, Di Carlo MN, Ciocci Pardo A, Salas N, Ragone MI, Felice JI, Cely-Ortiz A, Consolini AE, Portiansky E, Mosca S, Kranias EG, Wehrens XHT, Mattiazzi A. Ablation of phospholamban rescues reperfusion arrhythmias but exacerbates myocardium infarction in hearts with Ca2+/calmodulin kinase II constitutive phosphorylation of ryanodine receptors. Cardiovasc Res 2020; 115:556-569. [PMID: 30169578 DOI: 10.1093/cvr/cvy213] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [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: 04/24/2018] [Revised: 07/03/2018] [Accepted: 08/27/2018] [Indexed: 12/12/2022] Open
Abstract
AIMS Abnormal Ca2+ release from the sarcoplasmic reticulum (SR), associated with Ca2+-calmodulin kinase II (CaMKII)-dependent phosphorylation of RyR2 at Ser2814, has consistently been linked to arrhythmogenesis and ischaemia/reperfusion (I/R)-induced cell death. In contrast, the role played by SR Ca2+ uptake under these stress conditions remains controversial. We tested the hypothesis that an increase in SR Ca2+ uptake is able to attenuate reperfusion arrhythmias and cardiac injury elicited by increased RyR2-Ser2814 phosphorylation. METHODS AND RESULTS We used WT mice, which have been previously shown to exhibit a transient increase in RyR2-Ser2814 phosphorylation at the onset of reperfusion; mice with constitutive pseudo-phosphorylation of RyR2 at Ser2814 (S2814D) to exacerbate CaMKII-dependent reperfusion arrhythmias and cardiac damage, and phospholamban (PLN)-deficient-S2814D knock-in (SDKO) mice resulting from crossbreeding S2814D with phospholamban knockout deficient (PLNKO) mice. At baseline, S2814D and SDKO mice had structurally normal hearts. Moreover none of the strains were arrhythmic before ischaemia. Upon cardiac I/R, WT, and S2814D hearts exhibited abundant arrhythmias that were prevented by PLN ablation. In contrast, PLN ablation increased infarct size compared with WT and S2814D hearts. Mechanistically, the enhanced SR Ca2+ sequestration evoked by PLN ablation in SDKO hearts prevented arrhythmogenic events upon reperfusion by fragmenting SR Ca2+ waves into non-propagated and non-arrhythmogenic events (mini-waves). Conversely, the increase in SR Ca2+ sequestration did not reduce but rather exacerbated I/R-induced SR Ca2+ leak, as well as mitochondrial alterations, which were greatly avoided by inhibition of RyR2. These results indicate that the increase in SR Ca2+ uptake is ineffective in preventing the enhanced SR Ca2+ leak of PLN ablated myocytes from either entering into nearby mitochondria and/or activating additional CaMKII pathways, contributing to cardiac damage. CONCLUSION Our results demonstrate that increasing SR Ca2+ uptake by PLN ablation can prevent the arrhythmic events triggered by CaMKII-dependent phosphorylation of RyR2-induced SR Ca2+ leak. These findings underscore the benefits of increasing SERCA2a activity in the face of SR Ca2+ triggered arrhythmias. However, enhanced SERCA2a cannot prevent but rather exacerbates I/R cardiac injury.
Collapse
Affiliation(s)
- Carlos A Valverde
- Centro de Investigaciones Cardiovasculares 'Dr. Horacio E. Cingolani', CCT-La Plata-CONICET, Facultad de Cs. Médicas, UNLP, 60 y 120 s/n, La Plata CP, Argentina
| | - Gabriela Mazzocchi
- Centro de Investigaciones Cardiovasculares 'Dr. Horacio E. Cingolani', CCT-La Plata-CONICET, Facultad de Cs. Médicas, UNLP, 60 y 120 s/n, La Plata CP, Argentina
| | - Mariano N Di Carlo
- Centro de Investigaciones Cardiovasculares 'Dr. Horacio E. Cingolani', CCT-La Plata-CONICET, Facultad de Cs. Médicas, UNLP, 60 y 120 s/n, La Plata CP, Argentina
| | - Alejandro Ciocci Pardo
- Centro de Investigaciones Cardiovasculares 'Dr. Horacio E. Cingolani', CCT-La Plata-CONICET, Facultad de Cs. Médicas, UNLP, 60 y 120 s/n, La Plata CP, Argentina
| | - Nehuen Salas
- Centro de Investigaciones Cardiovasculares 'Dr. Horacio E. Cingolani', CCT-La Plata-CONICET, Facultad de Cs. Médicas, UNLP, 60 y 120 s/n, La Plata CP, Argentina
| | - María Ines Ragone
- Grupo de Farmacología Experimental, (GFEYEC), Departamento of Ciencias Biológicas, Facultad de Ciencias Exactas - CONICET., La Plata, Argentina
| | - Juan I Felice
- Centro de Investigaciones Cardiovasculares 'Dr. Horacio E. Cingolani', CCT-La Plata-CONICET, Facultad de Cs. Médicas, UNLP, 60 y 120 s/n, La Plata CP, Argentina
| | - Alejandra Cely-Ortiz
- Centro de Investigaciones Cardiovasculares 'Dr. Horacio E. Cingolani', CCT-La Plata-CONICET, Facultad de Cs. Médicas, UNLP, 60 y 120 s/n, La Plata CP, Argentina
| | - Alicia E Consolini
- Grupo de Farmacología Experimental, (GFEYEC), Departamento of Ciencias Biológicas, Facultad de Ciencias Exactas - CONICET., La Plata, Argentina
| | - Enrique Portiansky
- Laboratorio de Análisis de Imágenes, Facultad de Cs. Veterinarias, UNLP, La Plata, Argentina
| | - Susana Mosca
- Centro de Investigaciones Cardiovasculares 'Dr. Horacio E. Cingolani', CCT-La Plata-CONICET, Facultad de Cs. Médicas, UNLP, 60 y 120 s/n, La Plata CP, Argentina
| | - Evangelia G Kranias
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
| | - Xander H T Wehrens
- Department of Molecular Physiology and Biophysics, Cardiovascular Research Institute, Center for Space Medicine, Baylor College of Medicine, Houston, TX, USA.,Department of Medicine (in Cardiology), Cardiovascular Research Institute, Center for Space Medicine, Baylor College of Medicine, Houston, TX, USA.,Department of Pediatrics, Cardiovascular Research Institute, Center for Space Medicine, Baylor College of Medicine, Houston, TX, USA
| | - Alicia Mattiazzi
- Centro de Investigaciones Cardiovasculares 'Dr. Horacio E. Cingolani', CCT-La Plata-CONICET, Facultad de Cs. Médicas, UNLP, 60 y 120 s/n, La Plata CP, Argentina
| |
Collapse
|
16
|
Chowdhury SAK, Warren CM, Simon JN, Ryba DM, Batra A, Varga P, Kranias EG, Tardiff JC, Solaro RJ, Wolska BM. Modifications of Sarcoplasmic Reticulum Function Prevent Progression of Sarcomere-Linked Hypertrophic Cardiomyopathy Despite a Persistent Increase in Myofilament Calcium Response. Front Physiol 2020; 11:107. [PMID: 32210830 PMCID: PMC7075858 DOI: 10.3389/fphys.2020.00107] [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: 12/20/2019] [Accepted: 01/30/2020] [Indexed: 01/12/2023] Open
Abstract
Hypertrophic cardiomyopathy (HCM) is a genetic disorder caused by mutations in different genes mainly encoding myofilament proteins and therefore called a “disease of the sarcomere.” Despite the discovery of sarcomere protein mutations linked to HCM almost 30 years ago, the cellular mechanisms responsible for the development of this disease are not completely understood and likely vary among different mutations. Moreover, despite many efforts to develop effective treatments for HCM, these have largely been unsuccessful, and more studies are needed to better understand the cellular mechanisms of the disease. In experiments reported here, we investigated a mouse model expressing the mutant cTnT-R92Q, which is linked to HCM and induces an increase in myofilament Ca2+ sensitivity and diastolic dysfunction. We found that early correction of the diastolic dysfunction by phospholamban knockout (PLNKO) was able to prevent the development of the HCM phenotype in troponin T (TnT)-R92Q transgenic (TG) mice. Four groups of mice in FVB/N background were generated and used for the experiments: (1) non-transgenic (NTG)/PLN mice, which express wild-type TnT and normal level of PLN; (2) NTG/PLNKO mice, which express wild-type TnT and no PLN; (3) TG/PLN mice, which express TnT-R92Q and normal level of PLN; (4) TG/PLNKO mice, which express TnT-R92Q and no PLN. Cardiac function was determined using both standard echocardiographic parameters and speckle tracking strain measurements. We found that both atrial morphology and diastolic function were altered in TG/PLN mice but normal in TG/PLNKO mice. Histological analysis showed a disarray of myocytes and increased collagen deposition only in TG/PLN hearts. We also observed increased Ca2+/calmodulin-dependent protein kinase II (CaMKII) phosphorylation only in TG/PLN hearts but not in TG/PLNKO hearts. The rescue of the HCM phenotype was not associated with differences in myofilament Ca2+ sensitivity between TG/PLN and TG/PLNKO mice. Moreover, compared to standard systolic echo parameters, such as ejection fraction (EF), speckle strain measurements provided a more sensitive approach to detect early systolic dysfunction in TG/PLN mice. In summary, our results indicate that targeting diastolic dysfunction through altering Ca2+ fluxes with no change in myofilament response to Ca2+ was able to prevent the development of the HCM phenotype and should be considered as a potential additional treatment for HCM patients.
Collapse
Affiliation(s)
- Shamim A K Chowdhury
- Department of Physiology and Biophysics and the Center for Cardiovascular Research, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Chad M Warren
- Department of Physiology and Biophysics and the Center for Cardiovascular Research, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Jillian N Simon
- Department of Physiology and Biophysics and the Center for Cardiovascular Research, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - David M Ryba
- Department of Physiology and Biophysics and the Center for Cardiovascular Research, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Ashley Batra
- Department of Physiology and Biophysics and the Center for Cardiovascular Research, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Peter Varga
- Department of Pediatrics, Section of Cardiology, University of Illinois at Chicago, Chicago, IL, United States
| | - Evangelia G Kranias
- Department of Pharmacology and Systems Physiology, University of Cincinnati, Cincinnati, OH, United States
| | - Jil C Tardiff
- Department of Medicine, Division of Cardiology, The University of Arizona, Tucson, AZ, United States
| | - R John Solaro
- Department of Physiology and Biophysics and the Center for Cardiovascular Research, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Beata M Wolska
- Department of Physiology and Biophysics and the Center for Cardiovascular Research, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States.,Department of Medicine, Division of Cardiology, University of Illinois at Chicago, Chicago, IL, United States
| |
Collapse
|
17
|
Alogaili F, Chinnarasu S, Jaeschke A, Kranias EG, Hui DY. Hepatic HAX-1 inactivation prevents metabolic diseases by enhancing mitochondrial activity and bile salt export. J Biol Chem 2020; 295:4631-4646. [PMID: 32079675 DOI: 10.1074/jbc.ra119.012361] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 02/04/2020] [Indexed: 12/26/2022] Open
Abstract
Increasing hepatic mitochondrial activity through pyruvate dehydrogenase and elevating enterohepatic bile acid recirculation are promising new approaches for metabolic disease therapy, but neither approach alone can completely ameliorate disease phenotype in high-fat diet-fed mice. This study showed that diet-induced hepatosteatosis, hyperlipidemia, and insulin resistance can be completely prevented in mice with liver-specific HCLS1-associated protein X-1 (HAX-1) inactivation. Mechanistically, we showed that HAX-1 interacts with inositol 1,4,5-trisphosphate receptor-1 (InsP3R1) in the liver, and its absence reduces InsP3R1 levels, thereby improving endoplasmic reticulum-mitochondria calcium homeostasis to prevent excess calcium overload and mitochondrial dysfunction. As a result, HAX-1 ablation activates pyruvate dehydrogenase and increases mitochondria utilization of glucose and fatty acids to prevent hepatosteatosis, hyperlipidemia, and insulin resistance. In contrast to the reduction of InsP3R1 levels, hepatic HAX-1 deficiency increases bile salt exporter protein levels, thereby promoting enterohepatic bile acid recirculation, leading to activation of bile acid-responsive genes in the intestinal ileum to augment insulin sensitivity and of cholesterol transport genes in the liver to suppress hyperlipidemia. The dual mechanisms of increased mitochondrial respiration and enterohepatic bile acid recirculation due to improvement of endoplasmic reticulum-mitochondria calcium homeostasis with hepatic HAX-1 inactivation suggest that this may be a potential therapeutic target for metabolic disease intervention.
Collapse
Affiliation(s)
- Fawzi Alogaili
- Department of Pathology and Laboratory Medicine, Metabolic Diseases Research Center, University of Cincinnati College of Medicine, Cincinnati, Ohio 45237.,Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267
| | - Sivaprakasam Chinnarasu
- Department of Pathology and Laboratory Medicine, Metabolic Diseases Research Center, University of Cincinnati College of Medicine, Cincinnati, Ohio 45237
| | - Anja Jaeschke
- Department of Pathology and Laboratory Medicine, Metabolic Diseases Research Center, University of Cincinnati College of Medicine, Cincinnati, Ohio 45237
| | - Evangelia G Kranias
- Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267
| | - David Y Hui
- Department of Pathology and Laboratory Medicine, Metabolic Diseases Research Center, University of Cincinnati College of Medicine, Cincinnati, Ohio 45237
| |
Collapse
|
18
|
Essandoh K, Wang X, Huang W, Deng S, Gardner G, Mu X, Li Y, Kranias EG, Wang Y, Fan GC. Tumor susceptibility gene 101 ameliorates endotoxin-induced cardiac dysfunction by enhancing Parkin-mediated mitophagy. J Biol Chem 2019; 294:18057-18068. [PMID: 31619520 DOI: 10.1074/jbc.ra119.008925] [Citation(s) in RCA: 19] [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] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 10/10/2019] [Indexed: 12/28/2022] Open
Abstract
Cardiac mitochondrial damage and subsequent inflammation are hallmarks of endotoxin-induced myocardial depression. Activation of the Parkin/PTEN-induced kinase 1 (PINK1) pathway has been shown to promote autophagy of damaged mitochondria (mitophagy) and to protect from endotoxin-induced cardiac dysfunction. Tumor susceptibility gene 101 (TSG101) is a key member of the endosomal recycling complexes required for transport, which may affect autophagic flux. In this study, we investigated whether TSG101 regulates mitophagy and influences the outcomes of endotoxin-induced myocardial dysfunction. TSG101 transgenic and knockdown mice underwent endotoxin/lipopolysaccharide treatment (10 μg/g) and were assessed for survival, cardiac function, systemic/local inflammation, and activity of mitophagy mediators in the heart. Upon endotoxin challenge and compared with WT mice, TSG101 transgenic mice exhibited increased survival, preserved cardiac contractile function, reduced inflammation, and enhanced mitophagy activation in the heart. By contrast, TSG101 knockdown mice displayed opposite phenotypes during endotoxemia. Mechanistically, both coimmunoprecipitation assays and coimmunofluorescence staining revealed that TSG101 directly binds to Parkin in the cytosol of myocytes and facilitates translocation of Parkin from the cytosol to the mitochondria. Our results indicate that TSG101 elevation could protect against endotoxin-triggered myocardial injury by promoting Parkin-induced mitophagy.
Collapse
Affiliation(s)
- Kobina Essandoh
- Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267
| | - Xiaohong Wang
- Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267
| | - Wei Huang
- Department of Pathology and Laboratory Medicine, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267
| | - Shan Deng
- Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267; Department of Cardiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - George Gardner
- Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267
| | - Xingjiang Mu
- Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267
| | - Yutian Li
- Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267
| | - Evangelia G Kranias
- Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267
| | - Yigang Wang
- Department of Pathology and Laboratory Medicine, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267
| | - Guo-Chang Fan
- Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267.
| |
Collapse
|
19
|
Affiliation(s)
- Evangelia G Kranias
- From the Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, OH (E.G.K.)
| | - Pieter A Doevendans
- Netherlands Heart Institute, Utrecht (P.A.D.).,UMC Utrecht Department of Cardiology, The Netherlands; Central Military Hospital Utrecht, The Netherlands (P.A.D.)
| | - Pieter C Glijnis
- Phospholamban Foundation, Wieringerwerf, The Netherlands (P.C.G.)
| | - Roger J Hajjar
- Department of Cardiology, Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York (R.J.H.)
| |
Collapse
|
20
|
Abstract
The deletion of Arginine 14 of the phosholamban gene (PLN p.R14del) is associated with the pathogenesis of an inherited form of cardiomyopathy with prominent arrhythmias. Patients carrying the PLN R14del mutation are at risk of developing dilated cardiomyopathy or arrhythmogenic right ventricular cardiomyopathy. Although the genetic etiology is well defined, the molecular mechanism underlying the pathogenesis of PLN R14del-cardiomyopathy is unknown. Our CURE PLaN network, funded by the Foundation Leducq, will bring together leading scientists, clinicians, and patients to elucidate the genotype-phenotype relationships in R14del cardiomyopathy with the ultimate goal of developing innovative disease-specific therapeutic modalities. With the generous support of the Leducq Foundation, our Transatlantic Network of Excellence consortium to cure Phospholamban (PLN)-induced cardiomyopathy (CURE-PLaN) unites 6 leading centers to address the current challenges associated with arrhythmogenic right ventricular cardiomyopathy/dilated cardiomyopathy (DCM) with an initial focus on PLN and development of effective treatments. The Network is led by Evangelia (Litsa) Kranias (University of Cincinnati) in the United States and Pieter A. Doevendans (Netherlands Heart Institute/UMC Utrecht NL) in Europe. The other US project leaders are Kevin Costa (Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York) and Mark Mercola and Ioannis Karakikes (Stanford University), who are focusing on induced pluripotent stem cell (iPSC)-based disease models, tissue engineering, gene therapy, and drug discovery. On the European side, the project leaders are Despina Sanoudou (Biomedical Research Foundation of the Academy of Athens) analyzing the PLN interactome and Stephan Lehnart (University of Gottingen) addressing the subcellular and disrupted protein interactions affected in PLN-mutant cardiomyocytes. Other key members within the Netherlands Heart Institute are Peter van Tintelen on PLN genetics, Folkert Asselbergs on epigenetics and Rudolf de Boer on clinical trials. We are also privileged to get support from Arthur Wilde (University of Amsterdam), Sakthivel Sadayappan (University of Cincinnati), and Roger Hajjar (Phospholamban Foundation), who have had a long-standing interest in cardiac physiology and pathophysiology with emphasis on underlying pathways and potential therapeutic targets. The consortium is also fortunate to embrace a patient advocate, Pieter Glijnis, incorporating the voice of the patients to research in every step. Our goal is to build and share a platform of patient data coupled with in vitro and in vivo models to promote scientific discovery and advance novel treatments. Phospholamban is a small phosphoprotein in the cardiac sarcoplasmic reticulum, and it is the major regulator of SERCA2a activity and calcium (Ca)-cycling. Chronic inhibition of SERCA2a by PLN has been implicated in the aberrant Ca-cycling of failing hearts. Studies in HF models have shown that decreasing PLN activity may rescue cardiac remodeling and dysfunction. Several human PLN mutations, leading to inhibition of Ca-uptake into the sarcoplasmic reticulum, are linked to inherited DCM.
Collapse
Affiliation(s)
- Pieter A Doevendans
- From the Netherlands Heart Institute, Utrecht, the Netherlands (P.A.D.).,The Netherlands and UMC Utrecht Department of Cardiology and Central Military Hospital Utrecht, The Netherlands (P.A.D.)
| | - Pieter C Glijnis
- The Phospholamban Foundation: Zuidrak, Wieringerwerf, The Netherlands (P.C.G.)
| | - Evangelia G Kranias
- Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, OH (E.G.K.)
| |
Collapse
|
21
|
Gardner GT, Travers JG, Qian J, Liu GS, Haghighi K, Robbins N, Jiang M, Li Y, Fan GC, Rubinstein J, Blaxall BC, Kranias EG. Phosphorylation of Hsp20 Promotes Fibrotic Remodeling and Heart Failure. ACTA ACUST UNITED AC 2019; 4:188-199. [PMID: 31061921 PMCID: PMC6488766 DOI: 10.1016/j.jacbts.2018.11.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 09/27/2018] [Accepted: 11/14/2018] [Indexed: 01/28/2023]
Abstract
Cardiomyocyte-specific increases in phosphorylated Hsp20 (S16D-Hsp20) to levels similar to those observed in human failing hearts are associated with early fibrotic remodeling and depressed left ventricular function, symptoms which progress to heart failure and early death. The underlying mechanisms appear to involve translocation of phosphorylated Hsp20 to the nucleus and upregulation of interleukin (IL)-6, which subsequently activates cardiac fibroblasts in a paracrine fashion through transcription factor STAT3 signaling. Accordingly, treatment of S16D-Hsp20 mice with a rat anti-mouse IL-6 receptor monoclonal antibody (MR16-1) attenuated interstitial fibrosis and preserved cardiac function. These findings suggest that phosphorylated Hsp20 may be a potential therapeutic target in heart failure.
Collapse
Key Words
- Ccl2, C-C motif chemokine ligand 2
- Ccl3, C-C motif chemokine ligand 3
- Col1a1, collagen 1A1
- Col3A1, collagen 3A1
- ECM, extra-cellular matrix
- Hsp, heat shock protein
- Hsp20
- I/R, ischemia/reperfusion
- IL, interleukin
- IL-6
- Postn, periostin
- SMA, smooth muscle actin
- STAT3, signal transducer and activator of transcription 3
- TG, transgenic
- TGF, transforming growth factor
- TNF, tumor necrosis factor
- TUNEL, terminal deoxynucleotidyl transferase dUTP nick end labeling
- WT, wild type
- fibroblast
- heart failure
- remodeling
Collapse
Affiliation(s)
- George T Gardner
- Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Joshua G Travers
- Department of Pediatrics, Division of Molecular Cardiovascular Biology, The Heart Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Jiang Qian
- Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Guan-Sheng Liu
- Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Kobra Haghighi
- Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Nathan Robbins
- Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Min Jiang
- Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Yutian Li
- Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Guo-Chang Fan
- Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Jack Rubinstein
- Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Burns C Blaxall
- Department of Pediatrics, Division of Molecular Cardiovascular Biology, The Heart Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Evangelia G Kranias
- Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, Ohio.,Molecular Biology Division, Center for Basic Research, Biomedical Research Foundation of the Academy of Athens, Athens, Greece
| |
Collapse
|
22
|
Affiliation(s)
- Evangelia G Kranias
- From the Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, OH (E.G.K.); and Cardiovascular Research Center, Department of Cardiology, Icahn School of Medicine at Mount Sinai, New York, NY (R.J.H.).
| | - Roger J Hajjar
- From the Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, OH (E.G.K.); and Cardiovascular Research Center, Department of Cardiology, Icahn School of Medicine at Mount Sinai, New York, NY (R.J.H.)
| |
Collapse
|
23
|
Ren X, Roessler AE, Lynch TL, Haar L, Mallick F, Lui Y, Tranter M, Ren MH, Xie WR, Fan GC, Zhang JM, Kranias EG, Anjak A, Koch S, Jiang M, Miao Q, Wang Y, Cohen A, Rubinstein J, Weintraub NL, Jones WK. Cardioprotection via the skin: nociceptor-induced conditioning against cardiac MI in the NIC of time. Am J Physiol Heart Circ Physiol 2018; 316:H543-H553. [PMID: 30575436 DOI: 10.1152/ajpheart.00094.2018] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [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] [Indexed: 12/15/2022]
Abstract
Timely reperfusion is still the most effective approach to limit infarct size in humans. Yet, despite advances in care and reduction in door-to-balloon times, nearly 25% of patients develop heart failure postmyocardial infarction, with its attendant morbidity and mortality. We previously showed that cardioprotection results from a skin incision through the umbilicus in a murine model of myocardial infarction. In the present study, we show that an electrical stimulus or topical capsaicin applied to the skin in the same region induces significantly reduced infarct size in a murine model. We define this class of phenomena as nociceptor-induced conditioning (NIC) based on the peripheral nerve mechanism of initiation. We show that NIC is effective both as a preconditioning and postconditioning remote stimulus, reducing infarct size by 86% and 80%, respectively. NIC is induced via activation of skin C-fiber nerves. Interestingly, the skin region that activates NIC is limited to the anterior of the T9-T10 vertebral region of the abdomen. Cardioprotection after NIC requires the integrity of the spinal cord from the region of stimulation to the thoracic vertebral region of the origin of the cardiac nerves but does not require that the cord be intact in the cervical region. Thus, we show that NIC is a reflex and not a central nervous system-mediated effect. The mechanism involves bradykinin 2 receptor activity and activation of PKC, specifically, PKC-α. The similarity of the neuroanatomy and conservation of the effectors of cardioprotection supports that NIC may be translatable to humans as a nontraumatic and practical adjunct therapy against ischemic disease. NEW & NOTEWORTHY This study shows that an electrical stimulus to skin sensory nerves elicits a very powerful cardioprotection against myocardial infarction. This stimulus works by a neurogenic mechanism similar to that previously elucidated for remote cardioprotection of trauma. Nociceptor-induced conditioning is equally potent when applied before ischemia or at reperfusion and has great potential clinically.
Collapse
Affiliation(s)
- Xiaoping Ren
- Department of Molecular Pharmacology and Therapeutics, Loyola University Chicago, Mawood, Illinois
| | - Anne E Roessler
- Department of Molecular Pharmacology and Therapeutics, Loyola University Chicago, Mawood, Illinois
| | - Thomas L Lynch
- Department of Molecular Pharmacology and Therapeutics, Loyola University Chicago, Mawood, Illinois
| | - Lauren Haar
- Department of Molecular Pharmacology and Therapeutics, Loyola University Chicago, Mawood, Illinois
| | - Faryal Mallick
- Division of Cardiology, Department of Medicine, University of Cincinnati College of Medicine , Cincinnati, Ohio
| | - Yong Lui
- Division of Cardiology, Department of Medicine, University of Cincinnati College of Medicine , Cincinnati, Ohio
| | - Michael Tranter
- Division of Cardiology, Department of Medicine, University of Cincinnati College of Medicine , Cincinnati, Ohio
| | - Michelle Huan Ren
- Division of Cardiology, Department of Medicine, University of Cincinnati College of Medicine , Cincinnati, Ohio
| | - Wen Rui Xie
- Department of Anesthesiology and Department of Medicine, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Guo-Chang Fan
- Department of Pharmacology, University of Cincinnati , Cincinnati, Ohio
| | - Jun-Ming Zhang
- Department of Anesthesiology and Department of Medicine, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | | | - Ahmad Anjak
- Division of Cardiology, Department of Medicine, University of Cincinnati College of Medicine , Cincinnati, Ohio
| | - Sheryl Koch
- Division of Cardiology, Department of Medicine, University of Cincinnati College of Medicine , Cincinnati, Ohio
| | - Min Jiang
- Division of Cardiology, Department of Medicine, University of Cincinnati College of Medicine , Cincinnati, Ohio
| | - Qing Miao
- Department of Molecular Pharmacology and Therapeutics, Loyola University Chicago, Mawood, Illinois
| | - Yang Wang
- Department of Molecular Pharmacology and Therapeutics, Loyola University Chicago, Mawood, Illinois
| | - Albert Cohen
- Department of Mathematics, Michigan State University , East Lansing, Michigan
| | - Jack Rubinstein
- Division of Cardiology, Department of Medicine, University of Cincinnati College of Medicine , Cincinnati, Ohio
| | - Neal L Weintraub
- Division of Cardiology, Georgia Regents University, Augusta, Geogia
| | - W Keith Jones
- Department of Molecular Pharmacology and Therapeutics, Loyola University Chicago, Mawood, Illinois
| |
Collapse
|
24
|
Hof IE, van der Heijden JF, Kranias EG, Sanoudou D, de Boer RA, van Tintelen JP, van der Zwaag PA, Doevendans PA. Prevalence and cardiac phenotype of patients with a phospholamban mutation. Neth Heart J 2018; 27:64-69. [PMID: 30547415 PMCID: PMC6352623 DOI: 10.1007/s12471-018-1211-4] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [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] [Indexed: 11/24/2022] Open
Abstract
Pathogenic mutations in the phospholamban (PLN) gene may give rise to inherited cardiomyopathies due to its role in calcium homeostasis. Several PLN mutations have been identified, with the R14del mutation being the most prevalent cardiomyopathy-related mutation in the Netherlands. It is present in patients diagnosed with arrhythmogenic cardiomyopathy as well as dilated cardiomyopathy. Awareness of the phenotype of this PLN mutation is of great importance, since many carriers remain to be identified. Patients with the R14del mutation are characterised by older age at onset, low-voltage electrocardiograms and a high frequency of ventricular arrhythmias. Additionally, these patients have a poor prognosis often with left ventricular dysfunction and early-onset heart failure. Therefore, when there is a suspicion of a PLN mutation, cardiac and genetic screening is strongly recommended.
Collapse
Affiliation(s)
- I E Hof
- Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands.
| | - J F van der Heijden
- Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - E G Kranias
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - D Sanoudou
- Department of Molecular Biology, Center of Basic Research, Biomedical Research Foundation of the Academy of Athens, Athens, Greece
| | - R A de Boer
- Department of Cardiology, University Medical Center Groningen, Groningen, The Netherlands
| | - J P van Tintelen
- Department of Clinical Genetics, Academic Medical Center, Amsterdam, The Netherlands
| | - P A van der Zwaag
- Department of Clinical Genetics, University Medical Center Groningen, Groningen, The Netherlands
| | - P A Doevendans
- Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands.,Department of Cardiology, Central Military Hospital, Utrecht, The Netherlands.,Netherlands Heart Institute, Utrecht, The Netherlands
| |
Collapse
|
25
|
Arvanitis DA, Vafiadaki E, Johnson DM, Kranias EG, Sanoudou D. The Histidine-Rich Calcium Binding Protein in Regulation of Cardiac Rhythmicity. Front Physiol 2018; 9:1379. [PMID: 30319456 PMCID: PMC6171002 DOI: 10.3389/fphys.2018.01379] [Citation(s) in RCA: 9] [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: 07/21/2018] [Accepted: 09/11/2018] [Indexed: 12/16/2022] Open
Abstract
Sudden unexpected cardiac death (SCD) accounts for up to half of all-cause mortality of heart failure patients. Standardized cardiology tools such as electrocardiography, cardiac imaging, electrophysiological and serum biomarkers cannot accurately predict which patients are at risk of life-threatening arrhythmic episodes. Recently, a common variant of the histidine-rich calcium binding protein (HRC), the Ser96Ala, was identified as a potent biomarker of malignant arrhythmia triggering in these patients. HRC has been shown to be involved in the regulation of cardiac sarcoplasmic reticulum (SR) Ca2+ cycling, by binding and storing Ca2+ in the SR, as well as interacting with the SR Ca2+ uptake and release complexes. The underlying mechanisms, elucidated by studies at the molecular, biochemical, cellular and intact animal levels, indicate that transversion of Ser96 to Ala results in abolishment of an HRC phosphorylation site by Fam20C kinase and dysregulation of SR Ca2+ cycling. This is mediated through aberrant SR Ca2+ release by the ryanodine receptor (RyR2) quaternary complex, due to the impaired HRC/triadin interaction, and depressed SR Ca2+ uptake by the sarco/endoplasmic reticulum Ca2+ ATPase (SERCA2) pump, due to the impaired HRC/SERCA2 interaction. Pharmacological intervention with KN-93, an inhibitor of Ca2+/calmodulin-dependent protein kinase II (CaMKII), in the HRC Ser96Ala mouse model, reduced the occurrence of malignant cardiac arrhythmias. Herein, we summarize the current evidence on the pivotal role of HRC in the regulation of cardiac rhythmicity and the importance of HRC Ser96Ala as a genetic modifier for arrhythmias in the setting of heart failure.
Collapse
Affiliation(s)
- Demetrios A Arvanitis
- Molecular Biology Division, Biomedical Research Foundation, Academy of Athens, Athens, Greece
| | - Elizabeth Vafiadaki
- Molecular Biology Division, Biomedical Research Foundation, Academy of Athens, Athens, Greece
| | - Daniel M Johnson
- Department of Cardiothoracic Surgery, Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, Netherlands
| | - Evangelia G Kranias
- Molecular Biology Division, Biomedical Research Foundation, Academy of Athens, Athens, Greece.,Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, OH, United States
| | - Despina Sanoudou
- Molecular Biology Division, Biomedical Research Foundation, Academy of Athens, Athens, Greece.,Clinical Genomics and Pharmacogenomics Unit, 4th Department of Internal Medicine, Attikon Hospital, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| |
Collapse
|
26
|
Tzimas C, Johnson DM, Santiago DJ, Vafiadaki E, Arvanitis DA, Davos CH, Varela A, Athanasiadis NC, Dimitriou C, Katsimpoulas M, Sonntag S, Kryzhanovska M, Shmerling D, Lehnart SE, Sipido KR, Kranias EG, Sanoudou D. Impaired calcium homeostasis is associated with sudden cardiac death and arrhythmias in a genetic equivalent mouse model of the human HRC-Ser96Ala variant. Cardiovasc Res 2018; 113:1403-1417. [PMID: 28859293 DOI: 10.1093/cvr/cvx113] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Accepted: 06/06/2017] [Indexed: 12/29/2022] Open
Abstract
Aims The histidine-rich calcium-binding protein (HRC) Ser96Ala variant has previously been identified as a potential biomarker for ventricular arrhythmias and sudden cardiac death in patients with idiopathic dilated cardiomyopathy. Herein, the role of this variant in cardiac pathophysiology is delineated through a novel mouse model, carrying the human mutation in the homologous mouse position. Methods and results The mouse HRC serine 81, homologous to human HRC serine 96, was mutated to alanine, using knock-in gene targeting. The HRC-Ser81Ala mice presented increased mortality in the absence of structural or histological abnormalities, indicating that early death may be arrhythmia-related. Indeed, under stress-but not baseline-conditions, the HRC-Ser81Ala mice developed ventricular arrhythmias, whilst at the cardiomyocyte level they exhibited increased occurrence of triggered activity. Cardiac contraction was decreased in vivo, ex vivo, and in vitro. Additionally, Ca2+ transients and SR Ca2+ load were both reduced suggesting that cytosolic Ca2+ overload is not the underlying proarrhythmic mechanism. Interestingly, total SR Ca2+ leak was increased in HRC-Ser81Ala cardiomyocytes, without an increase in Ca2+ spark and wave frequency. However, Ca2+ wave propagation was significantly slower and the duration of the associated Na/Ca exchange current was increased. Moreover, action potential duration was also increased. Notably, Ca2+/Calmodulin kinase II (CaMKII) phosphorylation of the ryanodine receptor was increased, whilst KN-93, an inhibitor of CaMKII, reduced the occurrence of arrhythmias. Conclusions The homologous mutation Ser81Ala in HRC in mice, corresponding to Ser96Ala in humans, is associated with sudden death and depressed cardiac function. Ventricular arrhythmias are related to abnormal Ca2+ cycling across the SR. The data further support a role for CaMKII with the perspective to treat arrhythmias through CaMKII inhibition.
Collapse
Affiliation(s)
- Christos Tzimas
- Department of Molecular Biology, Center of Basic Research, Biomedical Research Foundation, Academy of Athens, Soranou Efessiou 4, 115 27, Athens, Greece
| | - Daniel M Johnson
- Department of Cardiovascular Sciences, KU Leuven, Leuven, Belgium
| | | | - Elizabeth Vafiadaki
- Department of Molecular Biology, Center of Basic Research, Biomedical Research Foundation, Academy of Athens, Soranou Efessiou 4, 115 27, Athens, Greece
| | - Demetrios A Arvanitis
- Department of Molecular Biology, Center of Basic Research, Biomedical Research Foundation, Academy of Athens, Soranou Efessiou 4, 115 27, Athens, Greece
| | - Constantinos H Davos
- Department of Clinical, Experimental Surgery and Translational Research Center, Biomedical Research Foundation, Academy of Athens, Athens, Greece
| | - Aimilia Varela
- Department of Clinical, Experimental Surgery and Translational Research Center, Biomedical Research Foundation, Academy of Athens, Athens, Greece
| | - Nikolaos C Athanasiadis
- Department of Clinical, Experimental Surgery and Translational Research Center, Biomedical Research Foundation, Academy of Athens, Athens, Greece
| | - Constantinos Dimitriou
- Department of Clinical, Experimental Surgery and Translational Research Center, Biomedical Research Foundation, Academy of Athens, Athens, Greece
| | - Michalis Katsimpoulas
- Department of Clinical, Experimental Surgery and Translational Research Center, Biomedical Research Foundation, Academy of Athens, Athens, Greece
| | | | | | | | - Stephan E Lehnart
- Department of Cardiology and Pulmonology, Heart Research Center Goettingen, University Medical Center Goettingen, Goettingen, Germany
| | - Karin R Sipido
- Department of Cardiovascular Sciences, KU Leuven, Leuven, Belgium
| | - Evangelia G Kranias
- Department of Molecular Biology, Center of Basic Research, Biomedical Research Foundation, Academy of Athens, Soranou Efessiou 4, 115 27, Athens, Greece.,Department of Pharmacology and Cell Biophysics, College of Medicine, University of Cincinnati, Cincinnati, OH, USA
| | - Despina Sanoudou
- Department of Molecular Biology, Center of Basic Research, Biomedical Research Foundation, Academy of Athens, Soranou Efessiou 4, 115 27, Athens, Greece.,4th Department of Internal Medicine, Clinical Genomics and Pharmacogenomics Unit, Medical School, National and Kapodistrian University of Athens, Attikon University Hospital, Rimini 1, Chaidari 124 62, Greece
| |
Collapse
|
27
|
Liu GS, Gardner G, Adly G, Jiang M, Cai WF, Lam CK, Alogaili F, Robbins N, Rubinstein J, Kranias EG. A novel human S10F-Hsp20 mutation induces lethal peripartum cardiomyopathy. J Cell Mol Med 2018; 22:3911-3919. [PMID: 29761889 PMCID: PMC6050507 DOI: 10.1111/jcmm.13665] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [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: 12/05/2017] [Accepted: 03/30/2018] [Indexed: 01/20/2023] Open
Abstract
Heat shock protein 20 (Hsp20) has been shown to be a critical regulator of cardiomyocyte survival upon cardiac stress. In this study, we investigated the functional significance of a novel human Hsp20 mutation (S10F) in peripartum cardiomyopathy. Previous findings showed that cardiac-specific overexpression of this mutant were associated with reduced autophagy, left ventricular dysfunction and early death in male mice. However, this study indicates that females have normal function with no alterations in autophagy but died within a week after 1-4 pregnancies. Further examination of mutant females revealed left ventricular chamber dilation and hypertrophic remodelling. Echocardiography demonstrated increases in left ventricular end-systolic volume and left ventricular end-diastolic volume, while ejection fraction and fractional shortening were depressed following pregnancy. Subsequent studies revealed that cardiomyocyte apoptosis was elevated in mutant female hearts after the third delivery, associated with decreases in the levels of Bcl-2/Bax and Akt phosphorylation. These results indicate that the human S10F mutant is associated with dysregulation of cell survival signalling, accelerated heart failure and early death post-partum.
Collapse
Affiliation(s)
- Guan-Sheng Liu
- Department of Pharmacology & Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - George Gardner
- Department of Pharmacology & Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - George Adly
- Department of Pharmacology & Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Min Jiang
- Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Wen-Feng Cai
- Department of Pathology & Lab Medicine, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Chi Keung Lam
- Department of Pharmacology & Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Fawzi Alogaili
- Department of Pharmacology & Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Nathan Robbins
- Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Jack Rubinstein
- Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Evangelia G Kranias
- Department of Pharmacology & Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, OH, USA.,Molecular Biology Division, Center for Basic Research, Biomedical Research Foundation of the Academy of Athens, Athens, Greece
| |
Collapse
|
28
|
Liu GS, Zhu H, Cai WF, Wang X, Jiang M, Essandoh K, Vafiadaki E, Haghighi K, Lam CK, Gardner G, Adly G, Nicolaou P, Sanoudou D, Liang Q, Rubinstein J, Fan GC, Kranias EG. Regulation of BECN1-mediated autophagy by HSPB6: Insights from a human HSPB6 S10F mutant. Autophagy 2018; 14:80-97. [PMID: 29157081 DOI: 10.1080/15548627.2017.1392420] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
HSPB6/Hsp20 (heat shock protein family B [small] member 6) has emerged as a novel cardioprotector against stress-induced injury. We identified a human mutant of HSPB6 (HSPB6S10F) exclusively present in dilated cardiomyopathy (DCM) patients. Cardiac expression of this mutant in mouse hearts resulted in remodeling and dysfunction, which progressed to heart failure and early death. These detrimental effects were associated with reduced interaction of mutant HSPB6S10F with BECN1/Beclin 1, leading to BECN1 ubiquitination and its proteosomal degradation. As a result, autophagy flux was substantially inhibited and apoptosis was increased in HSPB6S10F-mutant hearts. In contrast, overexpression of wild-type HSPB6 (HSPB6 WT) not only increased BECN1 levels, but also competitively suppressed binding of BECN1 to BCL2, resulting in stimulated autophagy. Indeed, preinhibition of autophagy attenuated the cardioprotective effects of HSPB6 WT. Taken together, these findings reveal a new regulatory mechanism of HSPB6 in cell survival through its interaction with BECN1. Furthermore, Ser10 appears to be crucial for the protective effects of HSPB6 and transversion of this amino acid to Phe contributes to cardiomyopathy.
Collapse
Affiliation(s)
- Guan-Sheng Liu
- a Department of Pharmacology & System Physiology , University of Cincinnati College of Medicine, Cincinnati , OH , USA
| | - Hongyan Zhu
- a Department of Pharmacology & System Physiology , University of Cincinnati College of Medicine, Cincinnati , OH , USA
| | - Wen-Feng Cai
- b Department of Pathology & Lab Medicine , University of Cincinnati College of Medicine, Cincinnati , OH , USA
| | - Xiaohong Wang
- a Department of Pharmacology & System Physiology , University of Cincinnati College of Medicine, Cincinnati , OH , USA
| | - Min Jiang
- c Department of Internal Medicine , University of Cincinnati College of Medicine. Cincinnati , OH , USA
| | - Kobina Essandoh
- a Department of Pharmacology & System Physiology , University of Cincinnati College of Medicine, Cincinnati , OH , USA
| | - Elizabeth Vafiadaki
- d Molecular Biology Division, Center for Basic Research, Biomedical Research Foundation of the Academy of Athens , Athens , Greece
| | - Kobra Haghighi
- a Department of Pharmacology & System Physiology , University of Cincinnati College of Medicine, Cincinnati , OH , USA
| | - Chi Keung Lam
- a Department of Pharmacology & System Physiology , University of Cincinnati College of Medicine, Cincinnati , OH , USA
| | - George Gardner
- a Department of Pharmacology & System Physiology , University of Cincinnati College of Medicine, Cincinnati , OH , USA
| | - George Adly
- a Department of Pharmacology & System Physiology , University of Cincinnati College of Medicine, Cincinnati , OH , USA
| | - Persoulla Nicolaou
- a Department of Pharmacology & System Physiology , University of Cincinnati College of Medicine, Cincinnati , OH , USA
| | - Despina Sanoudou
- d Molecular Biology Division, Center for Basic Research, Biomedical Research Foundation of the Academy of Athens , Athens , Greece
| | - Qiangrong Liang
- e Department of Biomedical Sciences , New York Institute of Technology College of Osteopathic Medicine , Old Westbury , NY , USA
| | - Jack Rubinstein
- c Department of Internal Medicine , University of Cincinnati College of Medicine. Cincinnati , OH , USA
| | - Guo-Chang Fan
- a Department of Pharmacology & System Physiology , University of Cincinnati College of Medicine, Cincinnati , OH , USA
| | - Evangelia G Kranias
- a Department of Pharmacology & System Physiology , University of Cincinnati College of Medicine, Cincinnati , OH , USA.,d Molecular Biology Division, Center for Basic Research, Biomedical Research Foundation of the Academy of Athens , Athens , Greece
| |
Collapse
|
29
|
Bidwell PA, Liu GS, Nagarajan N, Lam CK, Haghighi K, Gardner G, Cai WF, Zhao W, Mugge L, Vafiadaki E, Sanoudou D, Rubinstein J, Lebeche D, Hajjar R, Sadoshima J, Kranias EG. HAX-1 regulates SERCA2a oxidation and degradation. J Mol Cell Cardiol 2017; 114:220-233. [PMID: 29169992 DOI: 10.1016/j.yjmcc.2017.11.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [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: 07/21/2017] [Revised: 10/30/2017] [Accepted: 11/19/2017] [Indexed: 01/14/2023]
Abstract
Ischemia/reperfusion injury is associated with contractile dysfunction and increased cardiomyocyte death. Overexpression of the hematopoietic lineage substrate-1-associated protein X-1 (HAX-1) has been shown to protect from cellular injury but the function of endogenous HAX-1 remains obscure due to early lethality of the knockout mouse. Herein we generated a cardiac-specific and inducible HAX-1 deficient model, which uncovered an unexpected role of HAX-1 in regulation of sarco/endoplasmic reticulum Ca-ATPase (SERCA2a) in ischemia/reperfusion injury. Although ablation of HAX-1 in the adult heart elicited no morphological alterations under non-stress conditions, it diminished contractile recovery and increased infarct size upon ischemia/reperfusion injury. These detrimental effects were associated with increased loss of SERCA2a. Enhanced SERCA2a degradation was not due to alterations in calpain and calpastatin levels or calpain activity. Conversely, HAX-1 overexpression improved contractile recovery and maintained SERCA2a levels. The regulatory effects of HAX-1 on SERCA2a degradation were observed at multiple levels, including intact hearts, isolated cardiomyocytes and sarcoplasmic reticulum microsomes. Mechanistically, HAX-1 ablation elicited increased production of reactive oxygen species at the sarco/endoplasic reticulum compartment, resulting in SERCA2a oxidation and a predisposition to its proteolysis. This effect may be mediated by NAPDH oxidase 4 (NOX4), a novel binding partner of HAX-1. Accordingly, NOX inhibition with apocynin abrogated the effects of HAX-1 ablation in hearts subjected to ischemia/reperfusion injury. Taken together, our findings reveal a role of HAX-1 in the regulation of oxidative stress and SERCA2a degradation, implicating its importance in calcium homeostasis and cell survival pathways.
Collapse
Affiliation(s)
- Philip A Bidwell
- Department of Pharmacology and Systems Physiology, University of Cincinnati, College of Medicine, Cincinnati, OH, USA
| | - Guan-Sheng Liu
- Department of Pharmacology and Systems Physiology, University of Cincinnati, College of Medicine, Cincinnati, OH, USA
| | - Narayani Nagarajan
- Department of Cell Biology and Molecular Medicine, Rutgers New Jersey Medical School, Newark, NJ, USA
| | - Chi Keung Lam
- Department of Pharmacology and Systems Physiology, University of Cincinnati, College of Medicine, Cincinnati, OH, USA
| | - Kobra Haghighi
- Department of Pharmacology and Systems Physiology, University of Cincinnati, College of Medicine, Cincinnati, OH, USA
| | - George Gardner
- Department of Pharmacology and Systems Physiology, University of Cincinnati, College of Medicine, Cincinnati, OH, USA
| | - Wen-Feng Cai
- Department of Pharmacology and Systems Physiology, University of Cincinnati, College of Medicine, Cincinnati, OH, USA
| | - Wen Zhao
- Department of Pharmacology and Systems Physiology, University of Cincinnati, College of Medicine, Cincinnati, OH, USA
| | - Luke Mugge
- Department of Pharmacology and Systems Physiology, University of Cincinnati, College of Medicine, Cincinnati, OH, USA
| | - Elizabeth Vafiadaki
- Molecular Biology Division, Biomedical Research Foundation, Academy of Athens, Athens, Greece
| | - Despina Sanoudou
- Molecular Biology Division, Biomedical Research Foundation, Academy of Athens, Athens, Greece; 4th Department of Internal Medicine, Attikon Hospital, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Jack Rubinstein
- Division of Cardiology, Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Djamel Lebeche
- Cardiovascular Research Center, Ichan School of Medicine at Mount Sinai, New York, NY, USA
| | - Roger Hajjar
- Cardiovascular Research Center, Ichan School of Medicine at Mount Sinai, New York, NY, USA
| | - Junichi Sadoshima
- Department of Cell Biology and Molecular Medicine, Rutgers New Jersey Medical School, Newark, NJ, USA
| | - Evangelia G Kranias
- Department of Pharmacology and Systems Physiology, University of Cincinnati, College of Medicine, Cincinnati, OH, USA; Molecular Biology Division, Biomedical Research Foundation, Academy of Athens, Athens, Greece.
| |
Collapse
|
30
|
Bidwell PA, Haghighi K, Kranias EG. The antiapoptotic protein HAX-1 mediates half of phospholamban's inhibitory activity on calcium cycling and contractility in the heart. J Biol Chem 2017; 293:359-367. [PMID: 29150445 DOI: 10.1074/jbc.ra117.000128] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [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: 09/27/2017] [Revised: 11/17/2017] [Indexed: 12/25/2022] Open
Abstract
The antiapoptotic protein HAX-1 (HS-associated protein X-1) localizes to sarcoplasmic reticulum (SR) in the heart and interacts with the small membrane protein phospholamban (PLN), inhibiting the cardiac sarco/endoplasmic reticulum calcium ATPase 2a (SERCA2a) in the regulation of overall calcium handling and heart muscle contractility. However, because global HAX-1 deletion causes early lethality, how much endogenous HAX-1 contributes to PLN's inhibitory activity on calcium cycling is unknown. We therefore generated a cardiac-specific and inducible knock-out mouse model. HAX-1 ablation in the adult heart significantly increased contractile parameters and calcium kinetics, associated with increased SR calcium load. These changes occurred without any changes in the protein expression of SERCA2a, PLN, and ryanodine receptor or in the PLN phosphorylation status. The enhanced calcium cycling in the HAX-1-depleted heart was mediated through increases in the calcium affinity of SERCA2a and reduced PLN-SERCA2a binding. Comparison of the HAX-1 deletion-induced stimulatory effects with those elicited by PLN ablation indicated that HAX-1 mediates ∼50% of the PLN-associated inhibitory effects in the heart. Stimulation with the inotropic and lusitropic agent isoproterenol eliminated the differences among wild-type, HAX-1-deficient, and PLN-deficient hearts, and maximally stimulated contractile and calcium kinetic parameters were similar among these three groups. Furthermore, PLN overexpression in the HAX-1-null cardiomyocytes did not elicit any inhibitory effects, indicating that HAX-1 may limit PLN activity. These findings suggest that HAX-1 is a major mediator of PLN's inhibitory activity and a critical gatekeeper of SR calcium cycling and contractility in the heart.
Collapse
Affiliation(s)
- Philip A Bidwell
- Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267
| | - Kobra Haghighi
- Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267
| | - Evangelia G Kranias
- Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267; Department of Molecular Biology, Center of Basic Research, Biomedical Research Foundation, Academy of Athens, 115 27 Athens, Greece.
| |
Collapse
|
31
|
Watanabe S, Ishikawa K, Fish K, Oh JG, Motloch LJ, Kohlbrenner E, Lee P, Xie C, Lee A, Liang L, Kho C, Leonardson L, McIntyre M, Wilson S, Samulski RJ, Kranias EG, Weber T, Akar FG, Hajjar RJ. Protein Phosphatase Inhibitor-1 Gene Therapy in a Swine Model of Nonischemic Heart Failure. J Am Coll Cardiol 2017; 70:1744-1756. [PMID: 28958332 DOI: 10.1016/j.jacc.2017.08.013] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [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: 07/05/2017] [Revised: 08/01/2017] [Accepted: 08/07/2017] [Indexed: 01/16/2023]
Abstract
BACKGROUND Increased protein phosphatase-1 in heart failure (HF) induces molecular changes deleterious to the cardiac cell. Inhibiting protein phosphatase-1 through the overexpression of a constitutively active inhibitor-1 (I-1c) has been shown to reverse cardiac dysfunction in a model of ischemic HF. OBJECTIVES This study sought to determine the therapeutic efficacy of a re-engineered adenoassociated viral vector carrying I-1c (BNP116.I-1c) in a preclinical model of nonischemic HF, and to assess thoroughly the safety of BNP116.I-1c gene therapy. METHODS Volume-overload HF was created in Yorkshire swine by inducing severe mitral regurgitation. One month after mitral regurgitation induction, pigs were randomized to intracoronary delivery of either BNP116.I-1c (n = 6) or saline (n = 7). Therapeutic efficacy and safety were evaluated 2 months after gene delivery. Additionally, 24 naive pigs received different doses of BNP116.I-1c for safety evaluation. RESULTS At 1 month after mitral regurgitation induction, pigs developed HF as evidenced by increased left ventricular end-diastolic pressure and left ventricular volume indexes. Treatment with BNP116.I-1c resulted in improved left ventricular ejection fraction (-5.9 ± 4.2% vs. 5.5 ± 4.0%; p < 0.001) and adjusted dP/dt maximum (-3.39 ± 2.44 s-1 vs. 1.30 ± 2.39 s-1; p = 0.007). Moreover, BNP116.I-1c-treated pigs also exhibited a significant increase in left atrial ejection fraction at 2 months after gene delivery (-4.3 ± 3.1% vs. 7.5 ± 3.1%; p = 0.02). In vitro I-1c gene transfer in isolated left atrial myocytes from both pigs and rats increased calcium transient amplitude, consistent with its positive impact on left atrial contraction. We found no evidence of adverse electrical remodeling, arrhythmogenicity, activation of a cellular immune response, or off-target organ damage by BNP116.I-1c gene therapy in pigs. CONCLUSIONS Intracoronary delivery of BNP116.I-1c was safe and improved contractility of the left ventricle and atrium in a large animal model of nonischemic HF.
Collapse
Affiliation(s)
- Shin Watanabe
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Kiyotake Ishikawa
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Kenneth Fish
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Jae Gyun Oh
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Lukas J Motloch
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Erik Kohlbrenner
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Philyoung Lee
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Chaoqin Xie
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Ahyoung Lee
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Lifan Liang
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Changwon Kho
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Lauren Leonardson
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, New York
| | | | | | - R Jude Samulski
- Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina
| | - Evangelia G Kranias
- Department of Pharmacology & Cell Biophysics, University of Cincinnati, Cincinnati, Ohio
| | - Thomas Weber
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Fadi G Akar
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Roger J Hajjar
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, New York.
| |
Collapse
|
32
|
Ceholski DK, Turnbull IC, Koplev S, Kong CW, Stillitano F, Nonnenmacher M, Haghighi K, Gorski PA, Cohen N, Kolokathis F, Kremastinos DT, Babu A, Li RA, Giannarelli C, Karakikes I, Kranias EG, Costa KD, Hajjar RJ. Abstract 185: Genome Editing of Isogenic Human Induced Pluripotent Stem Cells Allows for Functional and Transcriptomic Insights Into Hereditary Dilated Cardiomyopathy Caused by Phospholamban Mutations. Circ Res 2017. [DOI: 10.1161/res.121.suppl_1.185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Dilated cardiomyopathy (DCM) can be caused by genetic mutations in numerous cardiac proteins, including phospholamban (PLN). PLN mutations are quite rare and obtaining patient samples for mechanistic insights can be challenging. We used genome editing with CRISPR/Cas9 to successfully insert R14del and R9C PLN mutations into a human induced pluripotent stem cell (hiPSC) line from an individual with no cardiovascular disease. HiPSC-cardiomyocytes (hiPSC-CMs) with the inserted R14del PLN mutation recapitulate the phenotype observed in patient-derived R14del hiPSC-CMs, characterized by abnormal intracellular calcium cycling and arrhythmogenicity. Insertion of R9C PLN results in hiPSC-CMs displaying an abnormal response to β-agonists, defective calcium handling, and a hypertrophic phenotype. In human engineered cardiac tissues (hECTs) created from hiPSC-CMs in a 3D matrix, R14del results in a progressive worsening of developed force and R9C PLN demonstrates an abnormal lusitropic response following β-adrenergic stimulation. Further, transcriptional profiling using RNAseq suggests a role for lipid metabolism in R14del. DNA methylation studies showed that differentially expressed genes were enriched for lipoprotein metabolism and chylomicron-mediated lipid transport pathways in R14del PLN. This was also confirmed with the observation of lipid deposition in R14del hECTs and human myocardial tissues from explanted hearts of affected patients. Furthermore, small RNAseq identified 2 miRNAs that were differentially regulated in R14del hiPSC-CMs (miR-449c-5p and miR-483-3p). For R9C PLN, RNAseq suggests that the mutation results in profibrotic signaling, activation of autophagy, and an altered metabolic state. Our findings demonstrate that gene editing of hiPSCs can be used to successfully create models and delineate molecular mechanisms of human PLN mutations associated with DCM.
Collapse
Affiliation(s)
| | | | - Simon Koplev
- Icahn Sch of Medicine at Mount Sinai, New York, NY
| | | | | | | | | | | | | | | | | | - Arvind Babu
- Icahn Sch of Medicine at Mount Sinai, New York, NY
| | | | | | | | | | | | | |
Collapse
|
33
|
Stillitano F, Turnbull IC, Karakikes I, Nonnenmacher M, Backeris P, Hulot JS, Kranias EG, Hajjar RJ, Costa KD. Genomic correction of familial cardiomyopathy in human engineered cardiac tissues. Eur Heart J 2016; 37:3282-3284. [PMID: 27450564 DOI: 10.1093/eurheartj/ehw307] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Revised: 04/22/2016] [Accepted: 06/20/2016] [Indexed: 01/09/2023] Open
Abstract
In this study, we used three-dimensional human engineered cardiac tissue technology to directly show that phospholamban (PLN) R14del mutation impairs cardiac contractility and to demonstrate restoration of contractile properties with targeted genetic correction of this inheritable form of dilated cardiomyopathy.
Collapse
Affiliation(s)
- Francesca Stillitano
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, PO Box 1030, New York, NY 10029, USA
| | - Irene C Turnbull
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, PO Box 1030, New York, NY 10029, USA
| | - Ioannis Karakikes
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, PO Box 1030, New York, NY 10029, USA.,Department of Medicine, Division of Cardiovascular Medicine, Stanford Cardiovascular Institute, Stanford, CA 94305, USA
| | - Mathieu Nonnenmacher
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, PO Box 1030, New York, NY 10029, USA
| | - Peter Backeris
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, PO Box 1030, New York, NY 10029, USA
| | - Jean-Sébastien Hulot
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, PO Box 1030, New York, NY 10029, USA.,Sorbonne Universités, UPMC Univ Paris 06, AP-HP, Institute of Cardiometabolism and Nutrition (ICAN), Pitié-Salpêtrière Hospital, Paris F-75013, France
| | - Evangelia G Kranias
- Department of Pharmacology, University of Cincinnati, Cincinnati, OH 45267-0575, USA
| | - Roger J Hajjar
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, PO Box 1030, New York, NY 10029, USA
| | - Kevin D Costa
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, PO Box 1030, New York, NY 10029, USA
| |
Collapse
|
34
|
Lim S, Sato T, Marino F, Stillitano F, Pioner JM, Haase T, Pianezzi E, Sivakumaran P, Hernandez D, Wong RCB, Taylor C, Dusting G, Pebay A, Bayeva M, Chang HC, Shapiro JS, Yar S, Ardehali H, Camporeale A, Avalle L, Heymans S, Roman B, Kotelianski V, Poli V, Karakikes I, Nonnenmacher M, Ceholski D, Zhang L, Hulot JS, Cai CL, Kranias EG, Hajjar RJ, Racca AW, Klaiman JM, Guan X, Pabon L, Muskheli V, Macadangdang J, Kim DH, Mack DL, Childers MK, Tesi C, Poggesi C, Murry CE, Regnier M, Krause J, Mueller C, Stenzig J, Roethemeier C, Wild PS, Blankenberg S, Zeller T, Altomare C, Cervio E, Bolis S, Moccetti T, Camici GG, Barile L, Vassalli GG. Moderated Poster session - Genetic, Epigenetic & Integrative480Inhibiting mitochondrial fission with Mdivi-1 directs cardiac differentiation of human induced pluripotent stem cells via protein kinase CK2481A novel role of tristetraprolin in preventing mitochondrial dysfunction in the heart against iron deficiency by optimizing expression of Rieske iron-sulfur protein482Different therapeutic approaches to downregulate the activation of the hepatic interleukin-6/stat3/complement pathway in two models of autoimmune myocarditis483In vitro and in vivo genome engineering of Dilated Cardiomyopathy caused by phospholamban R14 deletion.484Contractile dysfunction of induced pluripotent stem cell-derived cardiomyocytes from a duchenne muscular dystrophy patient485Cigarette smoking increases expression of the G protein-coupled receptor 15 mRNA by change in CpG methylation486Cardiogenic potential of iPSC from cardiac progenitor cells. Cardiovasc Res 2016. [DOI: 10.1093/cvr/cvw146] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
35
|
Mazzocchi G, Sommese L, Palomeque J, Felice JI, Di Carlo MN, Fainstein D, Gonzalez P, Contreras P, Skapura D, McCauley MD, Lascano EC, Negroni JA, Kranias EG, Wehrens XHT, Valverde CA, Mattiazzi A. Phospholamban ablation rescues the enhanced propensity to arrhythmias of mice with CaMKII-constitutive phosphorylation of RyR2 at site S2814. J Physiol 2016; 594:3005-30. [PMID: 26695843 DOI: 10.1113/jp271622] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Accepted: 12/14/2015] [Indexed: 01/27/2023] Open
Abstract
KEY POINTS Mice with Ca(2+) -calmodulin-dependent protein kinase (CaMKII) constitutive pseudo-phosphorylation of the ryanodine receptor RyR2 at Ser2814 (S2814D(+/+) mice) exhibit a higher open probability of RyR2, higher sarcoplasmic reticulum (SR) Ca(2+) leak in diastole and increased propensity to arrhythmias under stress conditions. We generated phospholamban (PLN)-deficient S2814D(+/+) knock-in mice by crossing two colonies, S2814D(+/+) and PLNKO mice, to test the hypothesis that PLN ablation can prevent the propensity to arrhythmias of S2814D(+/+) mice. PLN ablation partially rescues the altered intracellular Ca(2+) dynamics of S2814D(+/+) hearts and myocytes, but enhances SR Ca(2+) sparks and leak on confocal microscopy. PLN ablation diminishes ventricular arrhythmias promoted by CaMKII phosphorylation of S2814 on RyR2. PLN ablation aborts the arrhythmogenic SR Ca(2+) waves of S2814D(+/+) and transforms them into non-propagating events. A mathematical human myocyte model replicates these results and predicts the increase in SR Ca(2+) uptake required to prevent the arrhythmias induced by a CaMKII-dependent leaky RyR2. ABSTRACT Mice with constitutive pseudo-phosphorylation at Ser2814-RyR2 (S2814D(+/+) ) have increased propensity to arrhythmias under β-adrenergic stress conditions. Although abnormal Ca(2+) release from the sarcoplasmic reticulum (SR) has been linked to arrhythmogenesis, the role played by SR Ca(2+) uptake remains controversial. We tested the hypothesis that an increase in SR Ca(2+) uptake is able to rescue the increased arrhythmia propensity of S2814D(+/+) mice. We generated phospholamban (PLN)-deficient/S2814D(+/+) knock-in mice by crossing two colonies, S2814D(+/+) and PLNKO mice (SD(+/+) /KO). SD(+/+) /KO myocytes exhibited both increased SR Ca(2+) uptake seen in PLN knock-out (PLNKO) myocytes and diminished SR Ca(2+) load (relative to PLNKO), a characteristic of S2814D(+/+) myocytes. Ventricular arrhythmias evoked by catecholaminergic challenge (caffeine/adrenaline) in S2814D(+/+) mice in vivo or programmed electric stimulation and high extracellular Ca(2+) in S2814D(+) /(-) hearts ex vivo were significantly diminished by PLN ablation. At the myocyte level, PLN ablation converted the arrhythmogenic Ca(2+) waves evoked by high extracellular Ca(2+) provocation in S2814D(+/+) mice into non-propagated Ca(2+) mini-waves on confocal microscopy. Myocyte Ca(2+) waves, typical of S2814D(+/+) mice, could be evoked in SD(+/+) /KO cells by partially inhibiting SERCA2a. A mathematical human myocyte model replicated these results and allowed for predicting the increase in SR Ca(2+) uptake required to prevent the arrhythmias induced by a Ca(2+) -calmodulin-dependent protein kinase (CaMKII)-dependent leaky RyR2. Our results demonstrate that increasing SR Ca(2+) uptake by PLN ablation can prevent the arrhythmic events triggered by SR Ca(2+) leak due to CaMKII-dependent phosphorylation of the RyR2-S2814 site and underscore the benefits of increasing SERCA2a activity on SR Ca(2+) -triggered arrhythmias.
Collapse
Affiliation(s)
- G Mazzocchi
- Centro de Investigaciones Cardiovasculares, CCT-La Plata-CONICET, Facultad de Cs Médicas, UNLP, La Plata, Argentina
| | - L Sommese
- Centro de Investigaciones Cardiovasculares, CCT-La Plata-CONICET, Facultad de Cs Médicas, UNLP, La Plata, Argentina
| | - J Palomeque
- Centro de Investigaciones Cardiovasculares, CCT-La Plata-CONICET, Facultad de Cs Médicas, UNLP, La Plata, Argentina
| | - J I Felice
- Centro de Investigaciones Cardiovasculares, CCT-La Plata-CONICET, Facultad de Cs Médicas, UNLP, La Plata, Argentina
| | - M N Di Carlo
- Centro de Investigaciones Cardiovasculares, CCT-La Plata-CONICET, Facultad de Cs Médicas, UNLP, La Plata, Argentina
| | - D Fainstein
- Centro de Investigaciones Cardiovasculares, CCT-La Plata-CONICET, Facultad de Cs Médicas, UNLP, La Plata, Argentina
| | - P Gonzalez
- Cátedra de Patología, Facultad de Cs Médicas, UNLP, La Plata, Argentina
| | - P Contreras
- Departamento de Fisiología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - D Skapura
- Departments of Molecular Physiology and Biophysics, Medicine (in Cardiology), and Pediatrics, Baylor College of Medicine, Cardiovascular Research Institute, Houston, TX, 77030, USA
| | - M D McCauley
- Departments of Molecular Physiology and Biophysics, Medicine (in Cardiology), and Pediatrics, Baylor College of Medicine, Cardiovascular Research Institute, Houston, TX, 77030, USA
| | - E C Lascano
- Departamento de Biología Comparada, Celular y Molecular, Universidad Favaloro, Ciudad Autónoma de Buenos Aires, Argentina
| | - J A Negroni
- Departamento de Biología Comparada, Celular y Molecular, Universidad Favaloro, Ciudad Autónoma de Buenos Aires, Argentina
| | - E G Kranias
- Department of Pharmacology, University of Cincinnati College of Medicine, Cincinnati, OH, 45267
| | - X H T Wehrens
- Departments of Molecular Physiology and Biophysics, Medicine (in Cardiology), and Pediatrics, Baylor College of Medicine, Cardiovascular Research Institute, Houston, TX, 77030, USA
| | - C A Valverde
- Centro de Investigaciones Cardiovasculares, CCT-La Plata-CONICET, Facultad de Cs Médicas, UNLP, La Plata, Argentina
| | - A Mattiazzi
- Centro de Investigaciones Cardiovasculares, CCT-La Plata-CONICET, Facultad de Cs Médicas, UNLP, La Plata, Argentina
| |
Collapse
|
36
|
Abstract
The various isoforms of the sarco/endoplasmic reticulum Ca(2+) ATPase (SERCA) are responsible for the Ca(2+) uptake from the cytosol into the endoplasmic or sarcoplasmic reticulum (ER/SR). In some tissues, the activity of SERCA can be modulated by binding partners, such as phospholamban and sarcolipin. The activity of SERCA can be characterized by its apparent affinity for Ca(2+) as well as maximal enzymatic velocity. Both parameters can be effectively determined by the protocol described here. Specifically, we describe the measurement of the rate of oxalate-facilitated (45)Ca uptake into the SR of crude mouse ventricular homogenates. This protocol can easily be adapted for different tissues and animal models as well as cultured cells.
Collapse
Affiliation(s)
- Philip A Bidwell
- Department of Pharmacology and Cell Biophysics, College of Medicine, University of Cincinnati, 231 Albert Sabin Way, Cincinnati, OH, 45267-0575, USA
| | - Evangelia G Kranias
- Department of Pharmacology and Cell Biophysics, College of Medicine, University of Cincinnati, 231 Albert Sabin Way, Cincinnati, OH, 45267-0575, USA.
| |
Collapse
|
37
|
Lam CK, Zhao W, Liu GS, Cai WF, Gardner G, Adly G, Kranias EG. HAX-1 regulates cyclophilin-D levels and mitochondria permeability transition pore in the heart. Proc Natl Acad Sci U S A 2015; 112:E6466-75. [PMID: 26553996 PMCID: PMC4664353 DOI: 10.1073/pnas.1508760112] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The major underpinning of massive cell death associated with myocardial infarction involves opening of the mitochondrial permeability transition pore (mPTP), resulting in disruption of mitochondria membrane integrity and programmed necrosis. Studies in human lymphocytes suggested that the hematopoietic-substrate-1 associated protein X-1 (HAX-1) is linked to regulation of mitochondrial membrane function, but its role in controlling mPTP activity remains obscure. Herein we used models with altered HAX-1 expression levels in the heart and uncovered an unexpected role of HAX-1 in regulation of mPTP and cardiomyocyte survival. Cardiac-specific HAX-1 overexpression was associated with resistance against loss of mitochondrial membrane potential, induced by oxidative stress, whereas HAX-1 heterozygous deficiency exacerbated vulnerability. The protective effects of HAX-1 were attributed to specific down-regulation of cyclophilin-D levels leading to reduction in mPTP activation. Accordingly, cyclophilin-D and mPTP were increased in heterozygous hearts, but genetic ablation of cyclophilin-D in these hearts significantly alleviated their susceptibility to ischemia/reperfusion injury. Mechanistically, alterations in cyclophilin-D levels by HAX-1 were contributed by the ubiquitin-proteosomal degradation pathway. HAX-1 overexpression enhanced cyclophilin-D ubiquitination, whereas proteosomal inhibition restored cyclophilin-D levels. The regulatory effects of HAX-1 were mediated through interference of cyclophilin-D binding to heat shock protein-90 (Hsp90) in mitochondria, rendering it susceptible to degradation. Accordingly, enhanced Hsp90 expression in HAX-1 overexpressing cardiomyocytes increased cyclophilin-D levels, as well as mPTP activation upon oxidative stress. Taken together, our findings reveal the role of HAX-1 in regulating cyclophilin-D levels via an Hsp90-dependent mechanism, resulting in protection against activation of mPTP and subsequent cell death responses.
Collapse
Affiliation(s)
- Chi Keung Lam
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, OH 45267-0575
| | - Wen Zhao
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, OH 45267-0575
| | - Guan-Sheng Liu
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, OH 45267-0575
| | - Wen-Feng Cai
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, OH 45267-0575
| | - George Gardner
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, OH 45267-0575
| | - George Adly
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, OH 45267-0575
| | - Evangelia G Kranias
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, OH 45267-0575
| |
Collapse
|
38
|
Liu B, Ho HT, Brunello L, Unudurthi SD, Lou Q, Belevych AE, Qian L, Kim DH, Cho C, Janssen PML, Hund TJ, Knollmann BC, Kranias EG, Györke S. Ablation of HRC alleviates cardiac arrhythmia and improves abnormal Ca handling in CASQ2 knockout mice prone to CPVT. Cardiovasc Res 2015; 108:299-311. [PMID: 26410369 DOI: 10.1093/cvr/cvv222] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [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: 05/18/2015] [Accepted: 09/17/2015] [Indexed: 01/02/2023] Open
Abstract
AIMS Cardiac calsequestrin (CASQ2) and histidine-rich Ca-binding protein (HRC) are sarcoplasmic reticulum (SR) Ca-binding proteins that regulate SR Ca release in mammalian heart. Deletion of either CASQ2 or HRC results in relatively mild phenotypes characterized by preserved cardiac structure and function, although CASQ2 knockout (KO), or Cnull, shows increased arrhythmia burden under conditions of catecholaminergic stress. We hypothesized that given the apparent overlap of functions of CASQ2 and HRC, simultaneous ablation of both would deteriorate the cardiac phenotype compared with the single knockouts. METHODS AND RESULTS In contrast to this expectation, double knockout (DKO) mice lacking both CASQ2 and HRC exhibited normal cardiac ejection fraction and ultrastructure. Moreover, the predisposition to catecholamine-dependent arrhythmia that characterizes the Cnull phenotype was alleviated in the DKO mice. At the myocyte level, DKO mice displayed Ca transients of normal amplitude; additionally, the frequency of spontaneous Ca waves and sparks in the presence of isoproterenol were decreased markedly compared with Cnull. Furthermore, restitution of SR Ca release was slowed in DKO myocytes compared with Cnull cells. CONCLUSION Our results suggest that rather than being functionally redundant, CASQ2 and HRC modulate cardiac ryanodine receptor-mediated (RyR2) Ca release in an opposing manner. In particular, while CASQ2 stabilizes RyR2 rendering it refractory in the diastolic phase, HRC enhances RyR2 activity facilitating RyR2 recovery from refractoriness.
Collapse
Affiliation(s)
- Bin Liu
- Department of Physiology and Cell Biology, College of Medicine, and Davis Heart and Lung Research Institute, The Ohio State University, 473 W. 12th Avenue, Columbus, OH 43210, USA
| | - Hsiang-Ting Ho
- Department of Physiology and Cell Biology, College of Medicine, and Davis Heart and Lung Research Institute, The Ohio State University, 473 W. 12th Avenue, Columbus, OH 43210, USA
| | - Lucia Brunello
- Department of Physiology and Cell Biology, College of Medicine, and Davis Heart and Lung Research Institute, The Ohio State University, 473 W. 12th Avenue, Columbus, OH 43210, USA
| | - Sathya D Unudurthi
- Department of Physiology and Cell Biology, College of Medicine, and Davis Heart and Lung Research Institute, The Ohio State University, 473 W. 12th Avenue, Columbus, OH 43210, USA
| | - Qing Lou
- Department of Physiology and Cell Biology, College of Medicine, and Davis Heart and Lung Research Institute, The Ohio State University, 473 W. 12th Avenue, Columbus, OH 43210, USA
| | - Andriy E Belevych
- Department of Physiology and Cell Biology, College of Medicine, and Davis Heart and Lung Research Institute, The Ohio State University, 473 W. 12th Avenue, Columbus, OH 43210, USA
| | - Lan Qian
- Department of Physiology and Cell Biology, College of Medicine, and Davis Heart and Lung Research Institute, The Ohio State University, 473 W. 12th Avenue, Columbus, OH 43210, USA
| | - Do Han Kim
- School of Life Sciences and Systems Biology Research Center, Gwangju Institute of Science and Technology (GIST), Gwangju, Korea
| | - Chunghee Cho
- School of Life Sciences and Systems Biology Research Center, Gwangju Institute of Science and Technology (GIST), Gwangju, Korea
| | - Paul M L Janssen
- Department of Physiology and Cell Biology, College of Medicine, and Davis Heart and Lung Research Institute, The Ohio State University, 473 W. 12th Avenue, Columbus, OH 43210, USA
| | - Thomas J Hund
- Department of Physiology and Cell Biology, College of Medicine, and Davis Heart and Lung Research Institute, The Ohio State University, 473 W. 12th Avenue, Columbus, OH 43210, USA
| | - Bjorn C Knollmann
- Division of Clinical Pharmacology, Vanderbilt University Medical School, Nashville, TN 37232, USA
| | - Evangelia G Kranias
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
| | - Sándor Györke
- Department of Physiology and Cell Biology, College of Medicine, and Davis Heart and Lung Research Institute, The Ohio State University, 473 W. 12th Avenue, Columbus, OH 43210, USA
| |
Collapse
|
39
|
Cai WF, Liu GS, Lam CK, Florea S, Qian J, Zhao W, Pritchard T, Haghighi K, Lebeche D, Lu LJ, Deng J, Fan GC, Hajjar RJ, Kranias EG. Up-regulation of micro-RNA765 in human failing hearts is associated with post-transcriptional regulation of protein phosphatase inhibitor-1 and depressed contractility. Eur J Heart Fail 2015; 17:782-93. [PMID: 26177627 DOI: 10.1002/ejhf.323] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [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: 12/11/2014] [Revised: 03/18/2015] [Accepted: 04/17/2015] [Indexed: 11/09/2022] Open
Abstract
AIMS Impaired sarcoplasmic reticulum (SR) Ca(2+) cycling and depressed contractility, a hallmark of human and experimental heart failure, has been partially attributed to increased protein phosphatase 1 (PP-1) activity, associated with down-regulation of its endogenous inhibitor-1. The levels and activity of inhibitor-1 are reduced in failing hearts, contributing to dephosphorylation and inactivation of key calcium cycling proteins. Therefore, we investigated the mechanisms that mediate decreases in inhibitor-1 by post-transcriptional modification. METHODS AND RESULTS Bioinformatics revealed that 17 human microRNAs may serve as modulators of inhibitor-1. However, real-time PCR analysis identified only one of these microRNAs, miR-765, as being increased in human failing hearts concomitant with decreased inhibitor-1 levels. Expression of miR-765 in HEK293 cells or mouse ventricular myocytes confirmed suppression of inhibitor-1 levels through binding of this miR-765 to the 3'-untranslated region of inhibitor-1 mRNA. To determine the functional significance of miR-765 in Ca(2+) cycling, pri-miR-765 as well as a non-translated nucleotide sequence (miR-Ctrl) were expressed in adult mouse ventricular myocytes. The inhibitor-1 expression levels were decreased, accompanied by enhanced PP-1 activity in the miR-765 cardiomyocytes, and these reflected depressed contractile mechanics and Ca(2+) transients, compared with the miR-Ctrl group. The depressive effects were associated with decreases in the phosphorylation of phospholamban and SR Ca(2+) load. These miR-765 negative inotropic effects were abrogated in inhibitor-1-deficient cardiomyocytes, suggesting its apparent specificity for inhibitor-1. CONCLUSIONS miR-765 levels are increased in human failing hearts. Such increases may contribute to depressed cardiac function through reduced inhibitor-1 expression and enhanced PP-1 activity, associated with reduced SR Ca(2+) load.
Collapse
Affiliation(s)
- Wen-Feng Cai
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Guan-Sheng Liu
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Chi Keung Lam
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Stela Florea
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Jiang Qian
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Wen Zhao
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Tracy Pritchard
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Kobra Haghighi
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Djamel Lebeche
- Cardiovascular Research Center, Mount Sinai School of Medicine, New York, NY, USA
| | - Long Jason Lu
- Division of Biomedical Informatics, Cincinnati Children's Hospital Research Foundation, Cincinnati, OH, USA
| | - Jingyuan Deng
- Division of Biomedical Informatics, Cincinnati Children's Hospital Research Foundation, Cincinnati, OH, USA
| | - Guo-Chang Fan
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Roger J Hajjar
- Cardiovascular Research Center, Mount Sinai School of Medicine, New York, NY, USA
| | - Evangelia G Kranias
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, OH, USA.,Molecular Biology Division, Center for Basic Research, Foundation for Biomedical Research of the Academy of Athens, Athens, Greece
| |
Collapse
|
40
|
Liu GS, Morales A, Vafiadaki E, Lam CK, Cai WF, Haghighi K, Adly G, Hershberger RE, Kranias EG. A novel human R25C-phospholamban mutation is associated with super-inhibition of calcium cycling and ventricular arrhythmia. Cardiovasc Res 2015; 107:164-74. [PMID: 25852082 DOI: 10.1093/cvr/cvv127] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [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: 12/11/2014] [Accepted: 03/20/2015] [Indexed: 12/26/2022] Open
Abstract
AIMS Depressed sarcoplasmic reticulum (SR) Ca(2+) cycling, a universal characteristic of human and experimental heart failure, may be associated with genetic alterations in key Ca(2+)-handling proteins. In this study, we identified a novel PLN mutation (R25C) in dilated cardiomyopathy (DCM) and investigated its functional significance in cardiomyocyte Ca(2+)-handling and contractility. METHODS AND RESULTS Exome sequencing identified a C73T substitution in the coding region of PLN in a family with DCM. The four heterozygous family members had implantable cardiac defibrillators, and three developed prominent ventricular arrhythmias. Overexpression of R25C-PLN in adult rat cardiomyocytes significantly suppressed the Ca(2+) affinity of SR Ca(2+)-ATPase (SERCA2a), resulting in decreased SR Ca(2+) content, Ca(2+) transients, and impaired contractile function, compared with WT-PLN. These inhibitory effects were associated with enhanced interaction of R25C-PLN with SERCA2, which was prevented by PKA phosphorylation. Accordingly, isoproterenol stimulation relieved the depressive effects of R25C-PLN in cardiomyocytes. However, R25C-PLN also elicited increases in the frequency of Ca(2+) sparks and waves as well as stress-induced aftercontractions. This was accompanied by increased Ca(2+)/calmodulin-dependent protein kinase II activity and hyper-phosphorylation of RyR2 at serine 2814. CONCLUSION The findings demonstrate that human R25C-PLN is associated with super-inhibition of SERCA2a and Ca(2+) transport as well as increased SR Ca(2+) leak, promoting arrhythmogenesis under stress conditions. This is the first mechanistic evidence that increased PLN inhibition may impact both SR Ca(2+) uptake and Ca(2+) release activities and suggests that the human R25C-PLN may be a prognostic factor for increased ventricular arrhythmia risk in DCM carriers.
Collapse
Affiliation(s)
- Guan-Sheng Liu
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, PO Box 670575, 231 Albert Sabin Way, Cincinnati, OH, USA
| | - Ana Morales
- Division of Human Genetics, Ohio State University College of Medicine, Columbus, OH, USA Dorothy M. Davis Heart and Lung Research Institute, Ohio State University College of Medicine, Columbus, OH 45267-0575, USA
| | - Elizabeth Vafiadaki
- Molecular Biology Division, Biomedical Research Foundation, Academy of Athens, Greece
| | - Chi Keung Lam
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, PO Box 670575, 231 Albert Sabin Way, Cincinnati, OH, USA
| | - Wen-Feng Cai
- Department of Pathology and Laboratory Medicine, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Kobra Haghighi
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, PO Box 670575, 231 Albert Sabin Way, Cincinnati, OH, USA
| | - George Adly
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, PO Box 670575, 231 Albert Sabin Way, Cincinnati, OH, USA
| | - Ray E Hershberger
- Division of Human Genetics, Ohio State University College of Medicine, Columbus, OH, USA Dorothy M. Davis Heart and Lung Research Institute, Ohio State University College of Medicine, Columbus, OH 45267-0575, USA Division of Cardiovascular Medicine, Department of Internal Medicine, Ohio State University College of Medicine, Columbus, OH, USA
| | - Evangelia G Kranias
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, PO Box 670575, 231 Albert Sabin Way, Cincinnati, OH, USA Molecular Biology Division, Biomedical Research Foundation, Academy of Athens, Greece
| |
Collapse
|
41
|
Haghighi K, Bidwell P, Kranias EG. Phospholamban interactome in cardiac contractility and survival: A new vision of an old friend. J Mol Cell Cardiol 2014; 77:160-7. [PMID: 25451386 DOI: 10.1016/j.yjmcc.2014.10.005] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [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: 08/12/2014] [Revised: 10/06/2014] [Accepted: 10/09/2014] [Indexed: 01/10/2023]
Abstract
Depressed sarcoplasmic reticulum (SR) calcium cycling, reflecting impaired SR Ca-transport and Ca-release, is a key and universal characteristic of human and experimental heart failure. These SR processes are regulated by multimeric protein complexes, including protein kinases and phosphatases as well as their anchoring and regulatory subunits that fine-tune Ca-handling in specific SR sub-compartments. SR Ca-transport is mediated by the SR Ca-ATPase (SERCA2a) and its regulatory phosphoprotein, phospholamban (PLN). Dephosphorylated PLN is an inhibitor of SERCA2a and phosphorylation by protein kinase A (PKA) or calcium-calmodulin-dependent protein kinases (CAMKII) relieves these inhibitory effects. Recent studies identified additional regulatory proteins, associated with PLN, that control SR Ca-transport. These include the inhibitor-1 (I-1) of protein phosphatase 1 (PP1), the small heat shock protein 20 (Hsp20) and the HS-1 associated protein X-1 (HAX1). In addition, the intra-luminal histidine-rich calcium binding protein (HRC) has been shown to interact with both SERCA2a and triadin. Notably, there is physical and direct interaction between these protein players, mediating a fine-cross talk between SR Ca-uptake, storage and release. Importantly, regulation of SR Ca-cycling by the PLN/SERCA interactome does not only impact cardiomyocyte contractility, but also survival and remodeling. Indeed, naturally occurring variants in these Ca-cycling genes modulate their activity and interactions with other protein partners, resulting in depressed contractility and accelerated remodeling. These genetic variants may serve as potential prognostic or diagnostic markers in cardiac pathophysiology.
Collapse
Affiliation(s)
- Kobra Haghighi
- Department of Pharmacology and Cell Biophysics, University of Cincinnati, College of Medicine, Cincinnati, OH 45267, USA
| | - Philip Bidwell
- Department of Pharmacology and Cell Biophysics, University of Cincinnati, College of Medicine, Cincinnati, OH 45267, USA
| | - Evangelia G Kranias
- Department of Pharmacology and Cell Biophysics, University of Cincinnati, College of Medicine, Cincinnati, OH 45267, USA.
| |
Collapse
|
42
|
Haghighi K, Pritchard TJ, Singh VP, Das P, Vanderbilt EL, Rubinstein J, Kranias EG. Abstract 34: A Human G109E Polymorphism in Inibitor-1 Compromises Cardiomyocyte Function and Induces Arrhythmias. Circ Res 2014. [DOI: 10.1161/res.115.suppl_1.34] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Protein phosphatase 1 (PP1) has emerged as a nodal regulator of function and survival in the heart. Indeed, the increased activity of this enzyme in failing hearts contributes to depressed SR Ca-cycling and deteriorative remodeling. PP1 is negatively regulated by endogenous inhibitor-1, which is considered a promising therapeutic target. Increases in inhibitor-1 activity and decreases in PP1 protect against ischemia/reperfusion injury, chronic isoproterenol stimulation and heart failure progression. We recently identified a polymorphism (G109E) in the inhibitor-1 gene in heart failure patients with a frequency of 6%. Expression of G109E (called mutant) in rat cardiomyocytes resulted in ~20% decreases in contractile parameters, Ca-transients and sarcoplasmic reticulum Ca-load. This depressed function was rescued by isoproterenol. Interestingly, when subjected to stress conditions (2 Hz +/- Iso), the mutant cells were more susceptible to aftercontractions. Similar findings were obtained by expression of G109E in inhibitor-1 knockout cardiomyocytes in the absence of endogenous protein. The underlying mechanisms included reduced binding of mutant to PP1, increased PP1 activity and hyper-phosphorylation of S2814 in ryanodine receptor (RyR), promoting aberrant SR Ca-release. These findings were also reflected by in vivo cardiac overexpression of G109E. Contractile and Ca-kinetic parameters were depressed by ~30% in mutant cardiomyocytes, while isoproterenol relieved these inhibitory effects. Stress conditions were associated with induction of Ca waves and aftercontractions in G109E cells. Furthermore, serial caffeine/Iso injections in vivo, elicited higher incidence of ventricular ectopy (bigeminy, trigeminy and non-sustained ventricular tachycardia) in mutant mice, whereas WTs had normal rhythm. Our findings suggest that G109E and increased PP1 may dephosphorylate the RyR and promote Ca-leak, in agreement with previous reports. Subsequently, the increased Ca-levels activate CAMK, leading to hyperphosphorylation of RyR and further increases in Ca-leak. Thus, inhibitor-1 is critical in cardiac function and represents a key control in balancing phosphatase/kinase activities to stabilize Ca-cycling in the heart.
Collapse
|
43
|
Lam CK, Zhao W, Cai W, Liu G, Bidwell P, Gardner G, Adly G, Kranias EG. Abstract 204: HAX-1: A Novel Regulator of Energetics and Oxidative Stress in the Heart. Circ Res 2014. [DOI: 10.1161/res.115.suppl_1.204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Sarcoplasmic reticulum (SR) calcium handling is central not only in the control of heart function during excitation-contraction coupling but also in mitochondrial energetics and apoptosis. Recent studies have identified the anti-apoptotic protein, HS-1 associated protein X-1 (HAX-1) as a novel regulator of SR calcium cycling. Although HAX-1 has been shown to localize to mitochondria in various tissues, we found out that it also localizes to SR through its interaction with phospholamban (PLN) in cardiac muscle. Acute or chronic overexpression of HAX-1 in cardiomyocytes promoted PLN inhibition on the calcium ATPase (SERCA) and decreased cardiomyocyte calcium kinetics and contractile parameters. Accordingly, ablation of HAX-1 significantly enhanced SERCA activity and calcium kinetics. Furthermore, the HAX-1/PLN interaction appeared to also regulate cardiomyocyte survival. Indeed, overexpression of HAX-1 and the associated depressed SR Ca-load attenuated endoplasmic reticulum stress induced apoptosis, as evidenced by reduction of both caspase-12 activation and pro-apoptotic transcription factor C/EBP homologous protein induction during ischemia/reperfusion injury. In addition, the depressed SR Ca-cycling by HAX-1 overexpression was associated with reduced mitochondrial Ca-load as reflected by: a) hyper-phosphorylation of pyruvate dehydrogenase (PDH) and decreases in its activity, to diminish ATP production consistent with the attenuated energetic demand in these hearts; and b) reduced levels of reactive oxygen species, indicating protection from oxidative damage and preserved mitochondrial integrity. These findings suggest that HAX-1 is a key regulator of Ca-cycling, apoptosis and energetics in the heart. Thus, decreases in HAX-1 levels, observed during ischemia/reperfusion injury, may contribute to the deteriorated function and progression to heart failure development.
Collapse
Affiliation(s)
| | - Wen Zhao
- Univ of Cincinnati, Cincinnati, OH
| | | | | | | | | | | | | |
Collapse
|
44
|
Zhao W, Shi X, Zhou W, Wang H, Geng X, Zhang S, Wang J, Kranias EG, Liu HM. Abstract 276: The Regulatory Effects Of Peroxiredoxin II On Phospholamban Phosphorylation And Cardiac Contractile Function In Vivo. Circ Res 2014. [DOI: 10.1161/res.115.suppl_1.276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Peroxiredoxin II (prxII), a cytosolic form of the anti-oxidant peroxiredoxin family, was recently found to be decreased in failing human hearts. Interestingly, in hyperdynamic hearts of two genetically modified mouse models with: a) phospholamban ablation; and b) overexpression of the active inhibitor-1 of protein phosphatase 1, the levels of this cellular peroxidase (prxII) were markedly increased. Acute overexpression of prxII by adenoviral-delivery in adult rat cardiomyocytes (Ad-prxII) was associated with decreases in the basal rates of contraction and relaxation, as well as calcium kinetics. Accordingly, Ad-prxII-AS infected cardiomyocytes exhibited enhanced contractile parameters and Ca-kinetics. The depressed or increased contractility by Ad-prxII or Ad-prxII-AS was associated with parallel decreases or increases in phosphorylation of phospholamban (Ser16 and Thr17). To determine the in vivo effects of prxII on cardiac contractility, three transgenic lines (TG) with 2-3 fold cardiac-specific overexpression of prxII were generated and their cardiac morphologic and functional phenotypes were characterized. The TG mice exhibited no alterations in cardiac pathology or morphology up to 4 months of age. However, langendorf perfusions revealed that cardiac contractility, including the rates of contraction and relaxation (±dp/dtmax) as well as the left ventricular end systolic pressure (LVESP), were significantly depressed in TG mice (to 75, 76 and 63%, respectively), compared to WTs (100%). The depressed function was not associated with any alterations in the expression levels of key SR calcium handling proteins: SERCA2, total phospholamban, calsequestrin and ryanodine receptor. However, the levels of the phosphorylated PLN at Ser16 were found to be reduced to 50% in the TG mice, compared to WTs. These findings indicate that prxII, an anti-oxidant protein, may regulate basal cardiac contractile performance in vivo through phospholamban phosphorylation.
Collapse
Affiliation(s)
- Wen Zhao
- Zhengzhou Univ, Zhengzhou, China
| | | | | | | | | | | | | | | | | |
Collapse
|
45
|
Ishikawa K, Fish KM, Tilemann L, Rapti K, Aguero J, Santos-Gallego CG, Lee A, Karakikes I, Xie C, Akar FG, Shimada YJ, Gwathmey JK, Asokan A, McPhee S, Samulski J, Samulski RJ, Sigg DC, Weber T, Kranias EG, Hajjar RJ. Cardiac I-1c overexpression with reengineered AAV improves cardiac function in swine ischemic heart failure. Mol Ther 2014; 22:2038-2045. [PMID: 25023328 DOI: 10.1038/mt.2014.127] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2014] [Accepted: 07/03/2014] [Indexed: 02/07/2023] Open
Abstract
Cardiac gene therapy has emerged as a promising option to treat advanced heart failure (HF). Advances in molecular biology and gene targeting approaches are offering further novel options for genetic manipulation of the cardiovascular system. The aim of this study was to improve cardiac function in chronic HF by overexpressing constitutively active inhibitor-1 (I-1c) using a novel cardiotropic vector generated by capsid reengineering of adeno-associated virus (BNP116). One month after a large anterior myocardial infarction, 20 Yorkshire pigs randomly received intracoronary injection of either high-dose BNP116.I-1c (1.0 × 10(13) vector genomes (vg), n = 7), low-dose BNP116.I-1c (3.0 × 10(12) vg, n = 7), or saline (n = 6). Compared to baseline, mean left ventricular ejection fraction increased by 5.7% in the high-dose group, and by 5.2% in the low-dose group, whereas it decreased by 7% in the saline group. Additionally, preload-recruitable stroke work obtained from pressure-volume analysis demonstrated significantly higher cardiac performance in the high-dose group. Likewise, other hemodynamic parameters, including stroke volume and contractility index indicated improved cardiac function after the I-1c gene transfer. Furthermore, BNP116 showed a favorable gene expression pattern for targeting the heart. In summary, I-1c overexpression using BNP116 improves cardiac function in a clinically relevant model of ischemic HF.
Collapse
Affiliation(s)
- Kiyotake Ishikawa
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Kenneth M Fish
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Lisa Tilemann
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Kleopatra Rapti
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Jaume Aguero
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Carlos G Santos-Gallego
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Ahyoung Lee
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Ioannis Karakikes
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Chaoqin Xie
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Fadi G Akar
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Yuichi J Shimada
- Department of Medicine, Beth Israel Medical Center, University Hospital and Manhattan Campus for the Albert Einstein College of Medicine, New York, New York, USA
| | | | - Aravind Asokan
- Gene Therapy Center, University of North Carolina, Chapel Hill, North Carolina, USA
| | | | | | | | - Daniel C Sigg
- Department of Integrative Biology and Physiology, University of Minnesota Twin Cities, Minneapolis, Minnesota, USA
| | - Thomas Weber
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Evangelia G Kranias
- Department of Pharmacology and Cell Biophysics, University of Cincinnati, Cincinnati, Ohio, USA
| | - Roger J Hajjar
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, New York, USA.
| |
Collapse
|
46
|
Vafiadaki E, Arvanitis DA, Papalouka V, Terzis G, Roumeliotis TI, Spengos K, Garbis SD, Manta P, Kranias EG, Sanoudou D. Muscle lim protein isoform negatively regulates striated muscle actin dynamics and differentiation. FEBS J 2014; 281:3261-79. [PMID: 24860983 DOI: 10.1111/febs.12859] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [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: 11/05/2013] [Revised: 05/14/2014] [Accepted: 05/22/2014] [Indexed: 11/28/2022]
Abstract
Muscle lim protein (MLP) has emerged as a critical regulator of striated muscle physiology and pathophysiology. Mutations in cysteine and glycine-rich protein 3 (CSRP3), the gene encoding MLP, have been directly associated with human cardiomyopathies, whereas aberrant expression patterns are reported in human cardiac and skeletal muscle diseases. Increasing evidence suggests that MLP has an important role in both myogenic differentiation and myocyte cytoarchitecture, although the full spectrum of its intracellular roles has not been delineated. We report the discovery of an alternative splice variant of MLP, designated as MLP-b, showing distinct expression in neuromuscular disease and direct roles in actin dynamics and muscle differentiation. This novel isoform originates by alternative splicing of exons 3 and 4. At the protein level, it contains the N-terminus first half LIM domain of MLP and a unique sequence of 22 amino acids. Physiologically, it is expressed during early differentiation, whereas its overexpression reduces C2C12 differentiation and myotube formation. This may be mediated through its inhibition of MLP/cofilin-2-mediated F-actin dynamics. In differentiated striated muscles, MLP-b localizes to the sarcomeres and binds directly to Z-disc components, including α-actinin, T-cap and MLP. The findings of the present study unveil a novel player in muscle physiology and pathophysiology that is implicated in myogenesis as a negative regulator of myotube formation, as well as in differentiated striated muscles as a contributor to sarcomeric integrity.
Collapse
Affiliation(s)
- Elizabeth Vafiadaki
- Molecular Biology Division, Biomedical Research Foundation of the Academy of Athens, Greece
| | | | | | | | | | | | | | | | | | | |
Collapse
|
47
|
Abstract
Phospholamban (PLN) is a phosphoprotein in cardiac sarcoplasmic reticulum (SR) that is a reversible regulator of the Ca2+-ATPase (SERCA2a) activity and cardiac contractility. Dephosphorylated PLN inhibits SERCA2a and PLN phosphorylation, at either Ser16 by PKA or Thr17 by Ca2+-calmodulin-dependent protein kinase (CaMKII), reverses this inhibition. Through this mechanism, PLN is a key modulator of SR Ca2+ uptake, Ca2+ load, contractility, and relaxation. PLN phosphorylation is also the main determinant of β1-adrenergic responses in the heart. Although phosphorylation of Thr17 by CaMKII contributes to this effect, its role is subordinate to the PKA-dependent increase in cytosolic Ca2+, necessary to activate CaMKII. Furthermore, the effects of PLN and its phosphorylation on cardiac function are subject to additional regulation by its interacting partners, the anti-apoptotic HAX-1 protein and Gm or the anchoring unit of protein phosphatase 1. Regulation of PLN activity by this multimeric complex becomes even more important in pathological conditions, characterized by aberrant Ca2+-cycling. In this scenario, CaMKII-dependent PLN phosphorylation has been associated with protective effects in both acidosis and ischemia/reperfusion. However, the beneficial effects of increasing SR Ca2+ uptake through PLN phosphorylation may be lost or even become deleterious, when these occur in association with alterations in SR Ca2+ leak. Moreover, a major characteristic in human and experimental heart failure (HF) is depressed SR Ca2+ uptake, associated with decreased SERCA2a levels and dephosphorylation of PLN, leading to decreased SR Ca2+ load and impaired contractility. Thus, the strategy of altering SERCA2a and/or PLN levels or activity to restore perturbed SR Ca2+ uptake is a potential therapeutic tool for HF treatment. We will review here the role of CaMKII-dependent phosphorylation of PLN at Thr17 on cardiac function under physiological and pathological conditions.
Collapse
Affiliation(s)
- Alicia Mattiazzi
- Facultad de Medicina, Centro de Investigaciones Cardiovasculares, Conicet La Plata-Universidad Nacional de La Plata La Plata, Argentina
| | - Evangelia G Kranias
- Department of Pharmacology and Cell Biophysics, College of Medicine, University of Cincinnati Cincinnati, OH, USA
| |
Collapse
|
48
|
Rubinstein J, Lasko VM, Koch SE, Singh VP, Carreira V, Robbins N, Patel AR, Jiang M, Bidwell P, Kranias EG, Jones WK, Lorenz JN. Novel role of transient receptor potential vanilloid 2 in the regulation of cardiac performance. Am J Physiol Heart Circ Physiol 2013; 306:H574-84. [PMID: 24322617 DOI: 10.1152/ajpheart.00854.2013] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [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: 01/10/2023]
Abstract
Transient receptor potential cation channels have been implicated in the regulation of cardiovascular function, but only recently has our laboratory described the vanilloid-2 subtype (TRPV2) in the cardiomyocyte, though its exact mechanism of action has not yet been established. This study tests the hypothesis that TRPV2 plays an important role in regulating myocyte contractility under physiological conditions. Therefore, we measured cardiac and vascular function in wild-type and TRPV2(-/-) mice in vitro and in vivo and found that TRPV2 deletion resulted in a decrease in basal systolic and diastolic function without affecting loading conditions or vascular tone. TRPV2 stimulation with probenecid, a relatively selective TRPV2 agonist, caused an increase in both inotropy and lusitropy in wild-type mice that was blunted in TRPV2(-/-) mice. We examined the mechanism of TRPV2 inotropy/lusitropy in isolated myocytes and found that it modulates Ca(2+) transients and sarcoplasmic reticulum Ca(2+) loading. We show that the activity of this channel is necessary for normal cardiac function and that there is increased contractility in response to agonism of TRPV2 with probenecid.
Collapse
Affiliation(s)
- Jack Rubinstein
- Division of Cardiovascular Diseases, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
49
|
Pritchard TJ, Kawase Y, Haghighi K, Anjak A, Cai W, Jiang M, Nicolaou P, Pylar G, Karakikes I, Rapti K, Rubinstein J, Hajjar RJ, Kranias EG. Active inhibitor-1 maintains protein hyper-phosphorylation in aging hearts and halts remodeling in failing hearts. PLoS One 2013; 8:e80717. [PMID: 24312496 PMCID: PMC3846572 DOI: 10.1371/journal.pone.0080717] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Accepted: 10/16/2013] [Indexed: 01/14/2023] Open
Abstract
Impaired sarcoplasmic reticulum calcium cycling and depressed contractility are key characteristics in heart failure. Defects in sarcoplasmic reticulum function are characterized by decreased SERCA2a Ca-transport that is partially attributable to dephosphorylation of its regulator phospholamban by increased protein phosphatase 1 activity. Inhibition of protein phosphatase 1 through activation of its endogenous inhibitor-1 has been shown to enhance cardiac Ca-handling and contractility as well as protect from pathological stress remodeling in young mice. In this study, we assessed the long-term effects of inducible expression of constitutively active inhibitor-1 in the adult heart and followed function and remodeling through the aging process, up to 20 months. Mice with inhibitor-1 had normal survival and similar function to WTs. There was no overt remodeling as evidenced by measures of left ventricular end-systolic and diastolic diameters and posterior wall dimensions, heart weight to tibia length ratio, and histology. Higher phosphorylation of phospholamban at both Ser16 and Thr17 was maintained in aged hearts with active inhibitor-1, potentially offsetting the effects of elevated Ser2815-phosphorylation in ryanodine receptor, as there were no increases in arrhythmias under stress conditions in 20-month old mice. Furthermore, long-term expression of active inhibitor-1 via recombinant adeno-associated virus type 9 gene transfer in rats with pressure-overload induced heart failure improved function and prevented remodeling, associated with increased phosphorylation of phospholamban at Ser16 and Thr17. Thus, chronic inhibition of protein phosphatase 1, through increases in active inhibitor-1, does not accelerate age-related cardiomyopathy and gene transfer of this molecule in vivo improves function and halts remodeling in the long term.
Collapse
Affiliation(s)
- Tracy J. Pritchard
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
| | - Yoshiaki Kawase
- Cardiovascular Research Center, Ichan School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Kobra Haghighi
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
| | - Ahmad Anjak
- Department of Internal Medicine, Division of Cardiovascular Diseases, University of Cincinnati, Cincinnati, Ohio, United States of America
| | - Wenfeng Cai
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
| | - Min Jiang
- Department of Internal Medicine, Division of Cardiovascular Diseases, University of Cincinnati, Cincinnati, Ohio, United States of America
| | - Persoulla Nicolaou
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
| | - George Pylar
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
| | - Ioannis Karakikes
- Cardiovascular Research Center, Ichan School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Kleopatra Rapti
- Cardiovascular Research Center, Ichan School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Jack Rubinstein
- Department of Internal Medicine, Division of Cardiovascular Diseases, University of Cincinnati, Cincinnati, Ohio, United States of America
| | - Roger J. Hajjar
- Cardiovascular Research Center, Ichan School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Evangelia G. Kranias
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
- * E-mail:
| |
Collapse
|
50
|
Vafiadaki E, Arvanitis DA, Sanoudou D, Kranias EG. Identification of a protein phosphatase-1/phospholamban complex that is regulated by cAMP-dependent phosphorylation. PLoS One 2013; 8:e80867. [PMID: 24244723 PMCID: PMC3828283 DOI: 10.1371/journal.pone.0080867] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Accepted: 10/17/2013] [Indexed: 11/19/2022] Open
Abstract
In human and experimental heart failure, the activity of the type 1 phosphatase is significantly increased, associated with dephosphorylation of phospholamban, inhibition of the sarco(endo)plasmic reticulum Ca2+ transport ATPase (SERCA2a) and depressed function. In the current study, we investigated the molecular mechanisms controlling protein phosphatase-1 activity. Using recombinant proteins and complementary in vitro binding studies, we identified a multi-protein complex centered on protein phosphatase-1 that includes its muscle specific glycogen-targeting subunit GM and substrate phospholamban. GM interacts directly with phospholamban and this association is mediated by the cytosolic regions of the proteins. Our findings suggest the involvement of GM in mediating formation of the phosphatase-1/GM/phospholamban complex through the direct and independent interactions of GM with both protein phosphatase-1 and phospholamban. Importantly, the protein phosphatase-1/GM/phospholamban complex dissociates upon protein kinase A phosphorylation, indicating its significance in the β-adrenergic signalling axis. Moreover, protein phosphatase-1 activity is regulated by two binding partners, inhibitor-1 and the small heat shock protein 20, Hsp20. Indeed, human genetic variants of inhibitor-1 (G147D) or Hsp20 (P20L) result in reduced binding and inhibition of protein phosphatase-1, suggesting aberrant enzymatic regulation in human carriers. These findings provide insights into the mechanisms underlying fine-tuned regulation of protein phosphatase-1 and its impact on the SERCA2/phospholamban interactome in cardiac function.
Collapse
Affiliation(s)
- Elizabeth Vafiadaki
- Molecular Biology Division, Biomedical Research Foundation, Academy of Athens, Athens, Greece
| | - Demetrios A. Arvanitis
- Molecular Biology Division, Biomedical Research Foundation, Academy of Athens, Athens, Greece
| | - Despina Sanoudou
- Molecular Biology Division, Biomedical Research Foundation, Academy of Athens, Athens, Greece
- Department of Pharmacology, Medical School, University of Athens, Greece
| | - Evangelia G. Kranias
- Molecular Biology Division, Biomedical Research Foundation, Academy of Athens, Athens, Greece
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
- * E-mail:
| |
Collapse
|