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Kiessling M, Djalinac N, Voglhuber J, Ljubojevic-Holzer S. Nuclear Calcium in Cardiac (Patho)Physiology: Small Compartment, Big Impact. Biomedicines 2023; 11:biomedicines11030960. [PMID: 36979939 PMCID: PMC10046765 DOI: 10.3390/biomedicines11030960] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 03/17/2023] [Indexed: 03/30/2023] Open
Abstract
The nucleus of a cardiomyocyte has been increasingly recognized as a morphologically distinct and partially independent calcium (Ca2+) signaling microdomain, with its own Ca2+-regulatory mechanisms and important effects on cardiac gene expression. In this review, we (1) provide a comprehensive overview of the current state of research on the dynamics and regulation of nuclear Ca2+ signaling in cardiomyocytes, (2) address the role of nuclear Ca2+ in the development and progression of cardiac pathologies, such as heart failure and atrial fibrillation, and (3) discuss novel aspects of experimental methods to investigate nuclear Ca2+ handling and its downstream effects in the heart. Finally, we highlight current challenges and limitations and recommend future directions for addressing key open questions.
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Affiliation(s)
- Mara Kiessling
- Department of Cardiology, Medical University of Graz, 8036 Graz, Austria
| | - Nataša Djalinac
- Department of Biology, University of Padua, 35122 Padova, Italy
| | - Julia Voglhuber
- Department of Cardiology, Medical University of Graz, 8036 Graz, Austria
- BioTechMed Graz, 8010 Graz, Austria
| | - Senka Ljubojevic-Holzer
- Department of Cardiology, Medical University of Graz, 8036 Graz, Austria
- BioTechMed Graz, 8010 Graz, Austria
- Gottfried Schatz Research Center, Division of Molecular Biology and Biochemistry, Medical University of Graz, 8010 Graz, Austria
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2
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The Therapeutic and Diagnostic Potential of Phospholipase C Zeta, Oocyte Activation, and Calcium in Treating Human Infertility. Pharmaceuticals (Basel) 2023; 16:ph16030441. [PMID: 36986540 PMCID: PMC10056371 DOI: 10.3390/ph16030441] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 02/19/2023] [Accepted: 03/06/2023] [Indexed: 03/17/2023] Open
Abstract
Oocyte activation, a fundamental event during mammalian fertilisation, is initiated by concerted intracellular patterns of calcium (Ca2+) release, termed Ca2+ oscillations, predominantly driven by testis-specific phospholipase C zeta (PLCζ). Ca2+ exerts a pivotal role in not just regulating oocyte activation and driving fertilisation, but also in influencing the quality of embryogenesis. In humans, a failure of Ca2+ release, or defects in related mechanisms, have been reported to result in infertility. Furthermore, mutations in the PLCζ gene and abnormalities in sperm PLCζ protein and RNA, have been strongly associated with forms of male infertility where oocyte activation is deficient. Concurrently, specific patterns and profiles of PLCζ in human sperm have been linked to parameters of semen quality, suggesting the potential for PLCζ as a powerful target for both therapeutics and diagnostics of human fertility. However, further to PLCζ and given the strong role played by Ca2+ in fertilisation, targets down- and up-stream of this process may also present a significantly similar level of promise. Herein, we systematically summarise recent advancements and controversies in the field to update expanding clinical associations between Ca2+-release, PLCζ, oocyte activation and human fertility. We discuss how such associations may potentially underlie defective embryogenesis and recurrent implantation failure following fertility treatments, alongside potential diagnostic and therapeutic avenues presented by oocyte activation for the diagnosis and treatment of human infertility.
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Nagy N, Tóth N, Nánási PP. Antiarrhythmic and Inotropic Effects of Selective Na +/Ca 2+ Exchanger Inhibition: What Can We Learn from the Pharmacological Studies? Int J Mol Sci 2022; 23:ijms232314651. [PMID: 36498977 PMCID: PMC9736231 DOI: 10.3390/ijms232314651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 11/15/2022] [Accepted: 11/16/2022] [Indexed: 11/25/2022] Open
Abstract
Life-long stable heart function requires a critical balance of intracellular Ca2+. Several ion channels and pumps cooperate in a complex machinery that controls the influx, release, and efflux of Ca2+. Probably one of the most interesting and most complex players of this crosstalk is the Na+/Ca2+ exchanger, which represents the main Ca2+ efflux mechanism; however, under some circumstances, it can also bring Ca2+ into the cell. Therefore, the inhibition of the Na+/Ca2+ exchanger has emerged as one of the most promising possible pharmacological targets to increase Ca2+ levels, to decrease arrhythmogenic depolarizations, and to reduce excessive Ca2+ influx. In line with this, as a response to increasing demand, several more or less selective Na+/Ca2+ exchanger inhibitor compounds have been developed. In the past 20 years, several results have been published regarding the effect of Na+/Ca2+ exchanger inhibition under various circumstances, e.g., species, inhibitor compounds, and experimental conditions; however, the results are often controversial. Does selective Na+/Ca2+ exchanger inhibition have any future in clinical pharmacological practice? In this review, the experimental results of Na+/Ca2+ exchanger inhibition are summarized focusing on the data obtained by novel highly selective inhibitors.
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Affiliation(s)
- Norbert Nagy
- ELKH-SZTE Research Group of Cardiovascular Pharmacology, 6720 Szeged, Hungary
- Department of Pharmacology and Pharmacotherapy, Albert Szent-Györgyi Medical School, University of Szeged, 6720 Szeged, Hungary
- Correspondence: ; Tel.: +36-62-545-682; Fax: +36-62-545-680
| | - Noémi Tóth
- ELKH-SZTE Research Group of Cardiovascular Pharmacology, 6720 Szeged, Hungary
| | - Péter P. Nánási
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
- Department of Dental Physiology and Pharmacology, Faculty of Dentistry, University of Debrecen, 4032 Debrecen, Hungary
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Demydenko K, Ekhteraei-Tousi S, Roderick HL. Inositol 1,4,5-trisphosphate receptors in cardiomyocyte physiology and disease. Philos Trans R Soc Lond B Biol Sci 2022; 377:20210319. [PMID: 36189803 PMCID: PMC9527928 DOI: 10.1098/rstb.2021.0319] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The contraction of cardiac muscle underlying the pumping action of the heart is mediated by the process of excitation-contraction coupling (ECC). While triggered by Ca2+ entry across the sarcolemma during the action potential, it is the release of Ca2+ from the sarcoplasmic reticulum (SR) intracellular Ca2+ store via ryanodine receptors (RyRs) that plays the major role in induction of contraction. Ca2+ also acts as a key intracellular messenger regulating transcription underlying hypertrophic growth. Although Ca2+ release via RyRs is by far the greatest contributor to the generation of Ca2+ transients in the cardiomyocyte, Ca2+ is also released from the SR via inositol 1,4,5-trisphosphate (InsP3) receptors (InsP3Rs). This InsP3-induced Ca2+ release modifies Ca2+ transients during ECC, participates in directing Ca2+ to the mitochondria, and stimulates the transcription of genes underlying hypertrophic growth. Central to these specific actions of InsP3Rs is their localization to responsible signalling microdomains, the dyad, the SR-mitochondrial interface and the nucleus. In this review, the various roles of InsP3R in cardiac (patho)physiology and the mechanisms by which InsP3 signalling selectively influences the different cardiomyocyte cell processes in which it is involved will be presented. This article is part of the theme issue ‘The cardiomyocyte: new revelations on the interplay between architecture and function in growth, health, and disease’.
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Affiliation(s)
- Kateryna Demydenko
- Laboratory of Experimental Cardiology, Department of Cardiovascular Sciences, KU Leuven, Leuven, Belgium
| | - Samaneh Ekhteraei-Tousi
- Laboratory of Experimental Cardiology, Department of Cardiovascular Sciences, KU Leuven, Leuven, Belgium
| | - H Llewelyn Roderick
- Laboratory of Experimental Cardiology, Department of Cardiovascular Sciences, KU Leuven, Leuven, Belgium
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Rajagopal V, Arumugam S, Hunter PJ, Khadangi A, Chung J, Pan M. The Cell Physiome: What Do We Need in a Computational Physiology Framework for Predicting Single-Cell Biology? Annu Rev Biomed Data Sci 2022; 5:341-366. [PMID: 35576556 DOI: 10.1146/annurev-biodatasci-072018-021246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Modern biology and biomedicine are undergoing a big data explosion, needing advanced computational algorithms to extract mechanistic insights on the physiological state of living cells. We present the motivation for the Cell Physiome project: a framework and approach for creating, sharing, and using biophysics-based computational models of single-cell physiology. Using examples in calcium signaling, bioenergetics, and endosomal trafficking, we highlight the need for spatially detailed, biophysics-based computational models to uncover new mechanisms underlying cell biology. We review progress and challenges to date toward creating cell physiome models. We then introduce bond graphs as an efficient way to create cell physiome models that integrate chemical, mechanical, electromagnetic, and thermal processes while maintaining mass and energy balance. Bond graphs enhance modularization and reusability of computational models of cells at scale. We conclude with a look forward at steps that will help fully realize this exciting new field of mechanistic biomedical data science. Expected final online publication date for the Annual Review of Biomedical Data Science, Volume 5 is August 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Vijay Rajagopal
- Department of Biomedical Engineering, University of Melbourne, Melbourne, Victoria, Australia;
| | - Senthil Arumugam
- Cellular Physiology Lab, Monash Biomedicine Discovery Institute, Faculty of Medicine, Nursing and Health Sciences; European Molecular Biological Laboratory (EMBL) Australia; and Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton/Melbourne, Victoria, Australia
| | - Peter J Hunter
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | - Afshin Khadangi
- Department of Biomedical Engineering, University of Melbourne, Melbourne, Victoria, Australia;
| | - Joshua Chung
- Department of Biomedical Engineering, University of Melbourne, Melbourne, Victoria, Australia;
| | - Michael Pan
- School of Mathematics and Statistics, University of Melbourne, Melbourne, Victoria, Australia
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Sun Z, Wang L, Han L, Wang Y, Zhou Y, Li Q, Wu Y, Talabieke S, Hou Y, Wu L, Liu R, Fu Z, You H, Li BY, Zheng Y, Luo D. Functional Calsequestrin-1 Is Expressed in the Heart and Its Deficiency Is Causally Related to Malignant Hyperthermia-Like Arrhythmia. Circulation 2021; 144:788-804. [PMID: 34162222 DOI: 10.1161/circulationaha.121.053255] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background: Calsequestrins (Casqs), comprising the Casq1 and Casq2 isoforms, buffer Ca2+ and regulate its release in the sarcoplasmic reticulum (SR) of skeletal and cardiac muscle, respectively. Human inherited diseases associated with mutations in CASQ1 or CASQ2 include malignant hyperthermia/environmental heat stroke (MH/EHS) and catecholaminergic polymorphic ventricular tachycardia. However, patients with an MH/EHS event often suffer from arrhythmia for which the underlying mechanism remains unknown. Methods: Working hearts from conventional (Casq1-KO) and cardiac-specific (Casq1-CKO) Casq1 knockout mice were monitored in vivo and ex vivo by electrocardiogram and electrical mapping, respectively. MH was induced by 2% isoflurane and treated intraperitoneally with dantrolene. Time-lapse imaging was used to monitor intracellular Ca2+ activity in isolated mouse cardiomyocytes or neonatal rat ventricular myocytes (NRVMs) with knockdown, over-expression or truncation of the Casq1 gene. Conformational change in both Casqs was determined by crosslinking Western blot analysis. Results: Like MH/EHS patients, Casq1-KO and Casq1-CKO mice had faster basal heart rate, and ventricular tachycardia upon exposure to 2% isoflurane, which could be relieved by dantrolene. Basal sinus tachycardia and ventricular ectopic electrical triggering also occurred in Casq1-KO hearts ex vivo. Accordingly, the ventricular cardiomyocytes from Casq1-CKO mice displayed dantrolene-sensitive increased Ca2+ waves and diastole premature Ca2+ transients/oscillations upon isoflurane. NRVMs with Casq1-knockdown had enhanced spontaneous Ca2+ sparks/transients upon isoflurane, while cells over-expressing Casq1 exhibited decreased Ca2+ sparks/transients that were absent in cells with truncation of 9 amino acids at the C-terminus of Casq1. Structural evaluation showed that most of the Casq1 protein was present as a polymer and physically interacted with RyR2 in the ventricular SR. The Casq1 isoform was also expressed in human myocardium. Mechanistically, exposure to 2% isoflurane or heating at 41ºC induced Casq1 oligomerization in mouse ventricular and skeletal muscle tissues, leading to a reduced Casq1/RyR2 interaction and increased RyR2 activity in the ventricle. Conclusions: Casq1 is expressed in the heart, where it regulates SR Ca2+ release and heart rate. Casq1 deficiency independently causes MH/EHS-like ventricular arrhythmia by trigger-induced Casq1 oligomerization and a relief of its inhibitory effect on RyR2-mediated Ca2+ release, thus revealing a new inherited arrhythmia and a novel mechanism for MH/EHS arrhythmogenesis.
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Affiliation(s)
- Zhipeng Sun
- Department of Pharmacology, School of Basic Medical Sciences, Beijing Key Laboratory of Metabolic Disturbance Related Cardiovascular Disease, Capital Medical University, Beijing 100069, P. R. China
| | - Luqi Wang
- Department of Pharmacology, School of Basic Medical Sciences, Beijing Key Laboratory of Metabolic Disturbance Related Cardiovascular Disease, Capital Medical University, Beijing 100069, P. R. China
| | - Lu Han
- Beijing Lab for Cardiovascular Precision Medicine, Beijing Anzhen Hospital, Capital Medical University, Beijing 100011, P. R. China
| | - Yue Wang
- Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, Beijing 100011, P. R. China
| | - Yuan Zhou
- Department of Cardiac Surgery, Beijing Anzhen Hospital, Capital Medical University, Beijing 100011, P. R. China
| | - Qiang Li
- Department of Pharmacology, School of Basic Medical Sciences, Beijing Key Laboratory of Metabolic Disturbance Related Cardiovascular Disease, Capital Medical University, Beijing 100069, P. R. China
| | - Yongquan Wu
- Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, Beijing 100011, P. R. China
| | - Shaletanati Talabieke
- Department of Pharmacology, School of Basic Medical Sciences, Beijing Key Laboratory of Metabolic Disturbance Related Cardiovascular Disease, Capital Medical University, Beijing 100069, P. R. China
| | - Yunlong Hou
- College of Integrated Traditional Chinese and Western Medicine, Hebei University of Chinese Medicine; National Key Laboratory of Collateral Disease Research and Innovative Chinese Medicine, Shijiazhuang 050200, P. R. China
| | - Lulin Wu
- Department of Pharmacology, School of Basic Medical Sciences, Beijing Key Laboratory of Metabolic Disturbance Related Cardiovascular Disease, Capital Medical University, Beijing 100069, P. R. China
| | - Ronghua Liu
- Department of Pharmacology, School of Basic Medical Sciences, Beijing Key Laboratory of Metabolic Disturbance Related Cardiovascular Disease, Capital Medical University, Beijing 100069, P. R. China
| | - Zhiping Fu
- Department of Pharmacology, School of Basic Medical Sciences, Beijing Key Laboratory of Metabolic Disturbance Related Cardiovascular Disease, Capital Medical University, Beijing 100069, P. R. China
| | - Hongjie You
- Department of Pharmacology, School of Basic Medical Sciences, Beijing Key Laboratory of Metabolic Disturbance Related Cardiovascular Disease, Capital Medical University, Beijing 100069, P. R. China
| | - Bai-Yan Li
- Department of Pharmacology, School of Pharmacy, Harbin Medical University, Harbin, 150081, P. R. China
| | - Yuanyuan Zheng
- Department of Pharmacology, School of Basic Medical Sciences, Beijing Key Laboratory of Metabolic Disturbance Related Cardiovascular Disease, Capital Medical University, Beijing 100069, P. R. China
| | - Dali Luo
- Department of Pharmacology, School of Basic Medical Sciences, Beijing Key Laboratory of Metabolic Disturbance Related Cardiovascular Disease, Capital Medical University, Beijing 100069, P. R. China
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Zhang XH, Morad M. Ca 2+ signaling of human pluripotent stem cells-derived cardiomyocytes as compared to adult mammalian cardiomyocytes. Cell Calcium 2020; 90:102244. [PMID: 32585508 PMCID: PMC7483365 DOI: 10.1016/j.ceca.2020.102244] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 06/10/2020] [Accepted: 06/11/2020] [Indexed: 12/23/2022]
Abstract
Human induced pluripotent stem cells derived cardiomyocytes (hiPSC-CMs) have been extensively used for in vitro modeling of human cardiovascular disease, drug screening and pharmacotherapy, but little rigorous studies have been reported on their biophysical or Ca2+ signaling properties. There is also considerable concern as to the level of their maturity and whether they can serve as reliable models for adult human cardiac myocytes. Ultrastructural difference such as lack of t-tubular network, their polygonal shapes, disorganized sarcomeric myofilament, and their rhythmic automaticity, among others, have been cited as evidence for immaturity of hiPSC-CMs. In this review, we will deal with Ca2+ signaling, its regulation, and its stage of maturity as compared to the mammalian adult cardiomyocytes. We shall summarize the data on functional aspects of Ca2+signaling and its parameters that include: L-type calcium channel (Cav1.2), ICa-induced Ca2+release, CICR, and its parameters, cardiac Na/Ca exchanger (NCX1), the ryanodine receptors (RyR2), sarco-reticular Ca2+pump, SERCA2a/PLB, and the contribution of mitochondrial Ca2+ to hiPSC-CMs excitation-contraction (EC)-coupling as compared with adult mammalian cardiomyocytes. The comparative studies suggest that qualitatively hiPSC-CMs have similar Ca2+signaling properties as those of adult cardiomyocytes, but quantitative differences do exist. This review, we hope, will allow the readers to judge for themselves to what extent Ca2+signaling of hiPSC-CMs represents the adult form of this signaling pathway, and whether these cells can be used as good models of human cardiomyocytes.
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Affiliation(s)
- Xiao-Hua Zhang
- Cardiac Signaling Center of University of South Carolina, Medical University of South Carolina, Clemson University, Charleston SC, United States
| | - Martin Morad
- Cardiac Signaling Center of University of South Carolina, Medical University of South Carolina, Clemson University, Charleston SC, United States.
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Calcium Oscillatory Patterns and Oocyte Activation During Fertilization: a Possible Mechanism for Total Fertilization Failure (TFF) in Human In Vitro Fertilization? Reprod Sci 2020; 28:639-648. [PMID: 32813196 DOI: 10.1007/s43032-020-00293-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Accepted: 08/06/2020] [Indexed: 10/23/2022]
Abstract
This paper reviews the effects of calcium oscillatory patterns in oocytes and early embryo development. Total fertilization failure (TFF) is the failure of fertilization in all oocytes in a human IVF cycle, even after treatment with intracytoplasmic sperm injection (ICSI). It is not well understood and currently attributed to oocyte activation deficiency. Calcium signaling is important in oocyte activation events. Calcium oscillations, in particular, have been reported in animal and human oocytes after fertilization. Abnormal calcium oscillations after fertilization may be the principal mechanism for TFF. While studies also establish strong associations between abnormal calcium oscillatory patterns and suboptimal developmental outcomes, critical basic parameters and their mechanism of action have yet to be identified. Empirical use of artificial oocyte activation (AOA) methods has shown initial success in helping patients overcome TFF. The AOA methods attempt to raise calcium levels after fertilization, but the efficacy and safety of these AOA methods are still in early stages of addressing TFF. Additional information about calcium oscillatory patterns and the effects of AOA in human ART may allow the prevention of TFF or allow treatment of TFF patients effectively and safely.
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Conrard L, Tyteca D. Regulation of Membrane Calcium Transport Proteins by the Surrounding Lipid Environment. Biomolecules 2019; 9:E513. [PMID: 31547139 PMCID: PMC6843150 DOI: 10.3390/biom9100513] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 09/09/2019] [Accepted: 09/10/2019] [Indexed: 12/11/2022] Open
Abstract
Calcium ions (Ca2+) are major messengers in cell signaling, impacting nearly every aspect of cellular life. Those signals are generated within a wide spatial and temporal range through a large variety of Ca2+ channels, pumps, and exchangers. More and more evidences suggest that Ca2+ exchanges are regulated by their surrounding lipid environment. In this review, we point out the technical challenges that are currently being overcome and those that still need to be defeated to analyze the Ca2+ transport protein-lipid interactions. We then provide evidences for the modulation of Ca2+ transport proteins by lipids, including cholesterol, acidic phospholipids, sphingolipids, and their metabolites. We also integrate documented mechanisms involved in the regulation of Ca2+ transport proteins by the lipid environment. Those include: (i) Direct interaction inside the protein with non-annular lipids; (ii) close interaction with the first shell of annular lipids; (iii) regulation of membrane biophysical properties (e.g., membrane lipid packing, thickness, and curvature) directly around the protein through annular lipids; and (iv) gathering and downstream signaling of several proteins inside lipid domains. We finally discuss recent reports supporting the related alteration of Ca2+ and lipids in different pathophysiological events and the possibility to target lipids in Ca2+-related diseases.
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Affiliation(s)
- Louise Conrard
- CELL Unit, de Duve Institute and Université catholique de Louvain, UCL B1.75.05, avenue Hippocrate, 75, B-1200 Brussels, Belgium
| | - Donatienne Tyteca
- CELL Unit, de Duve Institute and Université catholique de Louvain, UCL B1.75.05, avenue Hippocrate, 75, B-1200 Brussels, Belgium.
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Xue J, Yan X, Yang Y, Chen M, Wu L, Gou Z, Sun Z, Talabieke S, Zheng Y, Luo D. Connexin 43 dephosphorylation contributes to arrhythmias and cardiomyocyte apoptosis in ischemia/reperfusion hearts. Basic Res Cardiol 2019; 114:40. [DOI: 10.1007/s00395-019-0748-8] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Accepted: 08/19/2019] [Indexed: 12/28/2022]
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Sun Z, Yang Y, Wu L, Talabieke S, You H, Zheng Y, Luo D. Connexin 43-serine 282 modulates serine 279 phosphorylation in cardiomyocytes. Biochem Biophys Res Commun 2019; 513:567-572. [PMID: 30981509 DOI: 10.1016/j.bbrc.2019.04.032] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Accepted: 04/03/2019] [Indexed: 12/21/2022]
Abstract
Connexin 43 (Cx43) phosphorylation plays a pivotal role in cardiac electrical and contractile performance. In a previous study we have found that Cx43 phosphorylation at serine 282 (pS282) regulates cardiomyocyte survival. Considering that both sites are altered simultaneously in many studies, we designed this study to identify the status of S279 phosphorylation upon pS282 manipulation. In heterozygous mice with S282 gene substituted with alanine (S282A), we found ventricular arrhythmias with inhibition of Cx43 phosphorylation at both S282 and S279 in the hearts. In cultured neonatal rat ventricular myocytes (NRVMs), transfection of virus carrying S282A mutant also blocked Cx43 phosphorylation at both S279/282 and gap junction coupling, while expression of wild-type Cx43 or S279A did not. Further, NRVMs transfected with S282 phospho-mimicking mutant substituted with aspartate or treated with ATP exhibited promotions of Cx43 phosphorylation at S279/282 and intercellular communication. Therefore, this study demonstrated a regulatory role of Cx43-S282 on S279 phosphorylation in cardiomyocytes, and suggested an involvement of S279 in the Cx43-S282 mediated cardiomyocyte homeostasis.
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Affiliation(s)
- Zhipeng Sun
- Department of Pharmacology, Beijing Key Laboratory of Metabolic Disturbance Related Cardiovascular Disease, School of Basic Medical Sciences, Capital Medical University, Beijing, 100069, PR China
| | - Yutong Yang
- Department of Pharmacology, Beijing Key Laboratory of Metabolic Disturbance Related Cardiovascular Disease, School of Basic Medical Sciences, Capital Medical University, Beijing, 100069, PR China
| | - Lulin Wu
- Department of Pharmacology, Beijing Key Laboratory of Metabolic Disturbance Related Cardiovascular Disease, School of Basic Medical Sciences, Capital Medical University, Beijing, 100069, PR China
| | - Shaletanati Talabieke
- Department of Pharmacology, Beijing Key Laboratory of Metabolic Disturbance Related Cardiovascular Disease, School of Basic Medical Sciences, Capital Medical University, Beijing, 100069, PR China
| | - Hongjie You
- Department of Pharmacology, Beijing Key Laboratory of Metabolic Disturbance Related Cardiovascular Disease, School of Basic Medical Sciences, Capital Medical University, Beijing, 100069, PR China
| | - Yuanyuan Zheng
- Department of Pharmacology, Beijing Key Laboratory of Metabolic Disturbance Related Cardiovascular Disease, School of Basic Medical Sciences, Capital Medical University, Beijing, 100069, PR China
| | - Dali Luo
- Department of Pharmacology, Beijing Key Laboratory of Metabolic Disturbance Related Cardiovascular Disease, School of Basic Medical Sciences, Capital Medical University, Beijing, 100069, PR China.
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12
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Structural and Mechanistic Bases of Nuclear Calcium Signaling in Human Pluripotent Stem Cell-Derived Ventricular Cardiomyocytes. Stem Cells Int 2019; 2019:8765752. [PMID: 31065282 PMCID: PMC6466844 DOI: 10.1155/2019/8765752] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 12/10/2018] [Accepted: 01/08/2019] [Indexed: 11/23/2022] Open
Abstract
The loss of nonregenerative, terminally differentiated cardiomyocytes (CMs) due to aging or diseases is generally considered irreversible. Human pluripotent stem cells (hPSCs) can self-renew while maintaining their pluripotency to differentiate into all cell types, including ventricular (V) cardiomyocytes (CMs), to provide a potential unlimited ex vivo source of CMs for heart disease modeling, drug/cardiotoxicity screening, and cell-based therapies. In the human heart, cytosolic Ca2+ signals are well characterized but the contribution of nuclear Ca2+ is essentially unexplored. The present study investigated nuclear Ca2+ signaling in hPSC-VCMs. Calcium transient or sparks in hPSC-VCMs were measured by line scanning using a spinning disc confocal microscope. We observed that nuclear Ca2+, which stems from unitary sparks due to the diffusion of cytosolic Ca2+ that are mediated by RyRs on the nuclear reticulum, is functional. Parvalbumin- (PV-) mediated Ca2+ buffering successfully manipulated Ca2+ transient and stimuli-induced apoptosis in hPSC-VCMs. We also investigated the effect of Ca2+ on gene transcription in hPSC-VCMs, and the involvement of nuclear factor of activated T-cell (NFAT) pathway was identified. The overexpression of Ca2+-sensitive, nuclear localized Ca2+/calmodulin-dependent protein kinase II δB (CaMKIIδB) induced cardiac hypertrophy through nuclear Ca2+/CaMKIIδB/HDAC4/MEF2 pathway. These findings provide insights into nuclear Ca2+ signal in hPSC-VCMs, which may lead to novel strategies for maturation as well as improved systems for disease modeling, drug discovery, and cell-based therapies.
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13
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Connexin43 dephosphorylation at serine 282 is associated with connexin43-mediated cardiomyocyte apoptosis. Cell Death Differ 2019; 26:1332-1345. [PMID: 30770876 DOI: 10.1038/s41418-019-0277-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 01/02/2019] [Accepted: 01/04/2019] [Indexed: 02/06/2023] Open
Abstract
Gap junction protein connexin 43 (Cx43) plays an important role in regulating cardiomyocyte survival in addition to regulating electrical coordination. Cx43 dephosphorylation, found in severe cardiac pathologies, is thought to contribute to myocardial injury. However, the mechanisms underlying Cx43 mediation of cell survival and myocardial lesions remain unknown. Here, we found that transfecting an adenovirus carrying a mutant gene of Cx43-serine 282 substituted with alanine (S282A) into neonatal rat ventricular myocytes (NRVMs) induced cell apoptosis and Ca2+ transient desynchronization, whereas using gap junction inhibitor or knocking down Cx43 expression with Cx43-miRNA caused uncoupled Ca2+ signaling without cell death. Similarly, while Cx43-S282A+/+ failed in generation, Cx43-S282A+/- mice exhibited cardiomyocyte apoptosis and ventricular arrhythmias dependent on S282 dephosphorylation. Further, Cx43 dephosphorylation at S282 activated p38 mitogen-activated protein kinase (p38 MAPK), factor-associated suicide and the caspase-8 apoptotic pathway by physically interacting with p38 MAPK. These findings uncovered a specific Cx43 phosphorylation residue involved in regulating cardiomyocyte homeostasis. S282 phosphorylation deficiency acts as a trigger inducing cardiomyocyte apoptosis and cardiac arrhythmias, providing a potential mechanism for Cx43-mediated myocardial injury in severe cardiac diseases.
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14
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Hegyi B, Bers DM, Bossuyt J. CaMKII signaling in heart diseases: Emerging role in diabetic cardiomyopathy. J Mol Cell Cardiol 2019; 127:246-259. [PMID: 30633874 DOI: 10.1016/j.yjmcc.2019.01.001] [Citation(s) in RCA: 75] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Accepted: 01/04/2019] [Indexed: 02/07/2023]
Abstract
Calcium/calmodulin-dependent protein kinase II (CaMKII) is upregulated in diabetes and significantly contributes to cardiac remodeling with increased risk of cardiac arrhythmias. Diabetes is frequently associated with atrial fibrillation, coronary artery disease, and heart failure, which may further enhance CaMKII. Activation of CaMKII occurs downstream of neurohormonal stimulation (e.g. via G-protein coupled receptors) and involve various posttranslational modifications including autophosphorylation, oxidation, S-nitrosylation and O-GlcNAcylation. CaMKII signaling regulates diverse cellular processes in a spatiotemporal manner including excitation-contraction and excitation-transcription coupling, mechanics and energetics in cardiac myocytes. Chronic activation of CaMKII results in cellular remodeling and ultimately arrhythmogenic alterations in Ca2+ handling, ion channels, cell-to-cell coupling and metabolism. This review addresses the detrimental effects of the upregulated CaMKII signaling to enhance the arrhythmogenic substrate and trigger mechanisms in the heart. We also briefly summarize preclinical studies using kinase inhibitors and genetically modified mice targeting CaMKII in diabetes. The mechanistic understanding of CaMKII signaling, cardiac remodeling and arrhythmia mechanisms may reveal new therapeutic targets and ultimately better treatment in diabetes and heart disease in general.
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Affiliation(s)
- Bence Hegyi
- Department of Pharmacology, University of California Davis, Davis, CA, USA
| | - Donald M Bers
- Department of Pharmacology, University of California Davis, Davis, CA, USA.
| | - Julie Bossuyt
- Department of Pharmacology, University of California Davis, Davis, CA, USA
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15
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Chen M, Xu D, Wu AZ, Kranias E, Lin SF, Chen PS, Chen Z. Phospholamban regulates nuclear Ca 2+ stores and inositol 1,4,5-trisphosphate mediated nuclear Ca 2+ cycling in cardiomyocytes. J Mol Cell Cardiol 2018; 123:185-197. [PMID: 30261161 DOI: 10.1016/j.yjmcc.2018.09.008] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Revised: 09/04/2018] [Accepted: 09/21/2018] [Indexed: 01/15/2023]
Abstract
AIMS Phospholamban (PLB) is the key regulator of the cardiac Ca2+ pump (SERCA2a)-mediated sarcoplasmic reticulum Ca2+ stores. We recently reported that PLB is highly concentrated in the nuclear envelope (NE) from where it can modulate perinuclear Ca2+ handling of the cardiomyocytes (CMs). Since inositol 1,4,5-trisphosphate (IP3) receptor (IP3R) mediates nuclear Ca2+ release, we examined whether the nuclear pool of PLB regulates IP3-induced nuclear Ca2+ handling. METHODS AND RESULTS Fluo-4 based confocal Ca2+ imaging was performed to measure Ca2+ dynamics across both nucleus and cytosol in saponin-permeabilized CMs isolated from wild-type (WT) or PLB-knockout (PLB-KO) mice. At diastolic intracellular Ca2+ ([Ca2+]i = 100 nM), the Fab fragment of the monoclonal PLB antibody (anti-PLB Fab) facilitated the formation and increased the length of spontaneous Ca2+ waves (SCWs) originating from the nuclear region in CMs from WT but not from PLB-KO mice. We next examined nuclear Ca2+ activities at basal condition and after sequential addition of IP3, anti-PLB Fab, and the IP3R inhibitor 2-aminoethoxydiphenyl borate (2-APB) at a series of [Ca2+]i. In WT mice, at 10 nM [Ca2+]i where ryanodine receptor (RyR2) based spontaneous Ca2+ sparks rarely occurred, IP3 increased fluorescence amplitude (F/F0) of overall nuclear region to 1.19 ± 0.02. Subsequent addition of anti-PLB Fab significantly decreased F/F0 to 1.09 ± 0.02. At 50 nM [Ca2+]i, anti-PLB Fab not only decreased the overall nuclear F/F0 previously elevated by IP3, but also increased the amplitude and duration of spark-like nuclear Ca2+ release events. These nuclear Ca2+ releases were blocked by 2-APB. At 100 nM [Ca2+]i, IP3 induced short SCWs originating from nucleus. Anti-PLB Fab transformed those short waves into long SCWs with propagation from the nucleus into the cytosol. In contrast, neither nuclear nor cytosolic Ca2+ dynamics was affected by anti-PLB Fab in CMs from PLB-KO mice in all these conditions. Furthermore, in WT CMs pretreated with RyR2 blocker tetracaine, IP3 and anti-PLB Fab still increased the magnitude of nuclear Ca2+ release but failed to regenerate SCWs. Finally, anti-PLB Fab increased low Ca2+ affinity mag-fluo 4 fluorescence intensity in the lumen of NE of nuclei isolated from WT but not in PLB-KO mice. CONCLUSION PLB regulates nuclear Ca2+ handling. By increasing Ca2+ uptake into lumen of the NE and perhaps other perinuclear membranes, the acute reversal of PLB inhibition decreases global Ca2+ concentration at rest in the nucleoplasm, and increases Ca2+ release into the nucleus, through mechanisms involving IP3R and RyR2 in the vicinity.
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Affiliation(s)
- Mu Chen
- Krannert Institute of Cardiology, Indiana University, Indianapolis, IN, USA; Department of Cardiology, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Dongzhu Xu
- Krannert Institute of Cardiology, Indiana University, Indianapolis, IN, USA; Cardiovascular Division, Institute of Clinical Medicine, Faculty of Medicine, University of Tsukuba, Japan
| | - Adonis Z Wu
- Krannert Institute of Cardiology, Indiana University, Indianapolis, IN, USA
| | - Evangelia Kranias
- Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Shien-Fong Lin
- Krannert Institute of Cardiology, Indiana University, Indianapolis, IN, USA; Institute of Biomedical Engineering, College of Electrical and Computer Engineering, National Chiao Tung University, Hsin-Chu, Taiwan
| | - Peng-Sheng Chen
- Krannert Institute of Cardiology, Indiana University, Indianapolis, IN, USA
| | - Zhenhui Chen
- Krannert Institute of Cardiology, Indiana University, Indianapolis, IN, USA.
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16
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NR1 and NR3B Composed Intranuclear N-methyl-d-aspartate Receptor Complexes in Human Melanoma Cells. Int J Mol Sci 2018; 19:ijms19071929. [PMID: 29966365 PMCID: PMC6073738 DOI: 10.3390/ijms19071929] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Accepted: 06/27/2018] [Indexed: 01/05/2023] Open
Abstract
Heterotetrameric N-methyl-d-aspartate type glutamate receptors (NMDAR) are cationic channels primarily permeable for Ca2+. NR1 and NR3 subunits bind glycine, while NR2 subunits bind glutamate for full activation. As NR1 may contain a nuclear localization signal (NLS) that is recognized by importin-α, our aim was to investigate if NMDARs are expressed in the nuclei of melanocytes and melanoma cells. A detailed NMDAR subunit expression pattern was examined by RT-PCRs (reverse transcription followed by polymerase chain reaction), fractionated western blots and immunocytochemistry in human epidermal melanocytes and in human melanoma cell lines A2058, HT199, HT168M1, MEL35/0 and WM35. All kind of NMDAR subunits are expressed as mRNAs in melanocytes, as well as in melanoma cells, while NR2B protein remained undetectable in any cell type. Western blots proved the exclusive presence of NR1 and NR3B in nuclear fractions and immunocytochemistry confirmed NR1-NR3B colocalization inside the nuclei of all melanoma cells. The same phenomenon was not observed in melanocytes. Moreover, protein database analysis revealed a putative NLS in NR3B subunit. Our results support that unusual, NR1-NR3B composed NMDAR complexes are present in the nuclei of melanoma cells. This may indicate a new malignancy-related histopathological feature of melanoma cells and raises the possibility of a glycine-driven, NMDA-related nuclear Ca2+-signalling in these cells.
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17
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Zhang Y, Dong F, Liu Z, Guo J, Zhang J, Fang J. Nanosecond pulsed electric fields promoting the proliferation of porcine iliac endothelial cells: An in vitro study. PLoS One 2018; 13:e0196688. [PMID: 29715270 PMCID: PMC5929542 DOI: 10.1371/journal.pone.0196688] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Accepted: 04/17/2018] [Indexed: 01/04/2023] Open
Abstract
Currently, nanosecond pulsed electric fields (nsPEFs) with short pulse duration and non-thermal effects have various potential applications in medicine and biology, especially in tumor ablation. Additionally, there are a few investigations on its proliferative effects in the normal cell. Clinically, proliferation of endothelial cells can perhaps accelerate the stent endothelialization and reduce the risk of acute thrombosis. To explore the feasibility using nsPEFs to induce proliferation of endothelial cells, in this study, porcine iliac endothelial (PIEC) cell line was cultured and tested by CCK-8 assay after nsPEFs treatment. The results reflected that nsPEFs with low field strength (100ns, 5 kV/cm, 10 pulses) had a significant proliferative effect with an increase in the PIEC cell growth of 16% after a 48 hour’ post-treatment. To further understand the mechanism of cell proliferation, intracellular Ca2+ concentration was measured through fluo-4 AM and reactive oxygen species assay was applied to estimate the level of intracellular reactive oxygen species (ROS). Finally, the total nitric oxide assay for NO production in the cultured medium was evaluated. An enhanced concentration of intracellular Ca2+ and ROS were observed, while the concentration of extracellular NO also increased after nsPEFs treatment. Such experimental results demonstrated that nsPEFs with appropriate pulse parameters could effectively enhance cell proliferation on PIEC cells, and the cell proliferation associated strongly with the changes of intracellular Ca2+ concertation, ROS and NO production induced by nsPEFs treatment. This in vitro preliminary study indicates that as a novel physical doping, the nsPEFs have potential in stimulating endothelial cells to accelerate stent endothelialization.
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Affiliation(s)
- Yuchen Zhang
- Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, Beijing, China
| | - Feihong Dong
- Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
| | - Zhengxin Liu
- Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
| | - Jinsong Guo
- College of Engineering, Peking University, Beijing, China
| | - Jue Zhang
- Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
- College of Engineering, Peking University, Beijing, China
- * E-mail:
| | - Jing Fang
- Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
- College of Engineering, Peking University, Beijing, China
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18
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Dahl EF, Wu SC, Healy CL, Harsch BA, Shearer GC, O'Connell TD. Subcellular compartmentalization of proximal Gα q-receptor signaling produces unique hypertrophic phenotypes in adult cardiac myocytes. J Biol Chem 2018; 293:8734-8749. [PMID: 29610273 DOI: 10.1074/jbc.ra118.002283] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 03/13/2018] [Indexed: 12/12/2022] Open
Abstract
G protein-coupled receptors that signal through Gαq (Gq receptors), such as α1-adrenergic receptors (α1-ARs) or angiotensin receptors, share a common proximal signaling pathway that activates phospholipase Cβ1 (PLCβ1), which cleaves phosphatidylinositol 4,5-bisphosphate (PIP2) to produce inositol 1,4,5-trisphosphate (IP3) and diacylglycerol. Despite these common proximal signaling mechanisms, Gq receptors produce distinct physiological responses, yet the mechanistic basis for this remains unclear. In the heart, Gq receptors are thought to induce myocyte hypertrophy through a mechanism termed excitation-transcription coupling, which provides a mechanistic basis for compartmentalization of calcium required for contraction versus IP3-dependent intranuclear calcium required for hypertrophy. Here, we identified subcellular compartmentalization of Gq-receptor signaling as a mechanistic basis for unique Gq receptor-induced hypertrophic phenotypes in cardiac myocytes. We show that α1-ARs co-localize with PLCβ1 and PIP2 at the nuclear membrane. Further, nuclear α1-ARs induced intranuclear PLCβ1 activity, leading to histone deacetylase 5 (HDAC5) export and a robust transcriptional response (i.e. significant up- or down-regulation of 806 genes). Conversely, we found that angiotensin receptors localize to the sarcolemma and induce sarcolemmal PLCβ1 activity, but fail to promote HDAC5 nuclear export, while producing a transcriptional response that is mostly a subset of α1-AR-induced transcription. In summary, these results link Gq-receptor compartmentalization in cardiac myocytes to unique hypertrophic transcription. They suggest a new model of excitation-transcription coupling in adult cardiac myocytes that accounts for differential Gq-receptor localization and better explains distinct physiological functions of Gq receptors.
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Affiliation(s)
| | - Steven C Wu
- Integrative Biology and Physiology, University of Minnesota, Minneapolis, Minnesota 55455 and
| | - Chastity L Healy
- Integrative Biology and Physiology, University of Minnesota, Minneapolis, Minnesota 55455 and
| | - Brian A Harsch
- the Department of Nutritional Sciences, Pennsylvania State University, University Park, Pennsylvania 16802
| | - Gregory C Shearer
- the Department of Nutritional Sciences, Pennsylvania State University, University Park, Pennsylvania 16802
| | - Timothy D O'Connell
- Integrative Biology and Physiology, University of Minnesota, Minneapolis, Minnesota 55455 and
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19
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Effect of Andrographolide on Gene Expression Profile and Intracellular Calcium in Primary Rat Myocardium Microvascular Endothelial Cells. J Cardiovasc Pharmacol 2017; 70:369-381. [DOI: 10.1097/fjc.0000000000000528] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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20
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Berridge MJ. Vitamin D, reactive oxygen species and calcium signalling in ageing and disease. Philos Trans R Soc Lond B Biol Sci 2017; 371:rstb.2015.0434. [PMID: 27377727 DOI: 10.1098/rstb.2015.0434] [Citation(s) in RCA: 81] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/15/2016] [Indexed: 12/13/2022] Open
Abstract
Vitamin D is a hormone that maintains healthy cells. It functions by regulating the low resting levels of cell signalling components such as Ca(2+) and reactive oxygen species (ROS). Its role in maintaining phenotypic stability of these signalling pathways depends on the ability of vitamin D to control the expression of those components that act to reduce the levels of both Ca(2+) and ROS. This regulatory role of vitamin D is supported by both Klotho and Nrf2. A decline in the vitamin D/Klotho/Nrf2 regulatory network may enhance the ageing process, and this is well illustrated by the age-related decline in cognition in rats that can be reversed by administering vitamin D. A deficiency in vitamin D has also been linked to two of the major diseases in man: heart disease and Alzheimer's disease (AD). In cardiac cells, this deficiency alters the Ca(2+) transients to activate the gene transcriptional events leading to cardiac hypertrophy and the failing heart. In the case of AD, it is argued that vitamin D deficiency results in the Ca(2+) landscape that initiates amyloid formation, which then elevates the resting level of Ca(2+) to drive the memory loss that progresses to neuronal cell death and dementia.This article is part of the themed issue 'Evolution brings Ca(2+) and ATP together to control life and death'.
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21
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Torrealba N, Navarro-Marquez M, Garrido V, Pedrozo Z, Romero D, Eura Y, Villalobos E, Roa JC, Chiong M, Kokame K, Lavandero S. Herpud1 negatively regulates pathological cardiac hypertrophy by inducing IP3 receptor degradation. Sci Rep 2017; 7:13402. [PMID: 29042597 PMCID: PMC5645377 DOI: 10.1038/s41598-017-13797-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Accepted: 10/02/2017] [Indexed: 01/19/2023] Open
Abstract
Cardiac hypertrophy is an adaptive response triggered by pathological stimuli. Regulation of the synthesis and the degradation of the Ca2+ channel inositol 1,4,5-trisphosphate receptor (IP3R) affects progression to cardiac hypertrophy. Herpud1, a component of the endoplasmic reticulum-associated degradation (ERAD) complex, participates in IP3R1 degradation and Ca2+ signaling, but the cardiac function of Herpud1 remains unknown. We hypothesize that Herpud1 acts as a negative regulator of cardiac hypertrophy by regulating IP3R protein levels. Our results show that Herpud1-knockout mice exhibit cardiac hypertrophy and dysfunction and that decreased Herpud1 protein levels lead to elevated levels of hypertrophic markers in cultured rat cardiomyocytes. In addition, IP3R levels were elevated both in Herpud1-knockout mice and Herpud1 siRNA-treated rat cardiomyocytes. The latter treatment also led to elevated cytosolic and nuclear Ca2+ levels. In summary, the absence of Herpud1 generates a pathological hypertrophic phenotype by regulating IP3R protein levels. Herpud1 is a novel negative regulator of pathological cardiac hypertrophy.
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Affiliation(s)
- Natalia Torrealba
- Advanced Center for Chronic Disease (ACCDiS) & Center for Molecular Studies of the Cell (CEMC), Facultad de Ciencias Químicas y Farmacéuticas & Facultad de Medicina, Santiago, Chile
| | - Mario Navarro-Marquez
- Advanced Center for Chronic Disease (ACCDiS) & Center for Molecular Studies of the Cell (CEMC), Facultad de Ciencias Químicas y Farmacéuticas & Facultad de Medicina, Santiago, Chile
| | - Valeria Garrido
- Advanced Center for Chronic Disease (ACCDiS) & Center for Molecular Studies of the Cell (CEMC), Facultad de Ciencias Químicas y Farmacéuticas & Facultad de Medicina, Santiago, Chile
| | - Zully Pedrozo
- Advanced Center for Chronic Disease (ACCDiS) & Center for Molecular Studies of the Cell (CEMC), Facultad de Ciencias Químicas y Farmacéuticas & Facultad de Medicina, Santiago, Chile.,Instituto de Ciencias Biomédicas, Facultad de Medicina Universidad de Chile, Santiago, Chile
| | - Diego Romero
- Department of Pathology, Advanced Center for Chronic Diseases (ACCDiS), Faculty of Medicine, Pontifical Catholic University of Chile, Santiago, Chile
| | - Yuka Eura
- Department of Molecular Pathogenesis, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan
| | - Elisa Villalobos
- Advanced Center for Chronic Disease (ACCDiS) & Center for Molecular Studies of the Cell (CEMC), Facultad de Ciencias Químicas y Farmacéuticas & Facultad de Medicina, Santiago, Chile.,Department of Internal Medicine (Cardiology Division), University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Juan Carlos Roa
- Department of Pathology, Advanced Center for Chronic Diseases (ACCDiS), Faculty of Medicine, Pontifical Catholic University of Chile, Santiago, Chile
| | - Mario Chiong
- Advanced Center for Chronic Disease (ACCDiS) & Center for Molecular Studies of the Cell (CEMC), Facultad de Ciencias Químicas y Farmacéuticas & Facultad de Medicina, Santiago, Chile
| | - Koichi Kokame
- Department of Molecular Pathogenesis, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan.
| | - Sergio Lavandero
- Advanced Center for Chronic Disease (ACCDiS) & Center for Molecular Studies of the Cell (CEMC), Facultad de Ciencias Químicas y Farmacéuticas & Facultad de Medicina, Santiago, Chile. .,Instituto de Ciencias Biomédicas, Facultad de Medicina Universidad de Chile, Santiago, Chile. .,Department of Internal Medicine (Cardiology Division), University of Texas Southwestern Medical Center, Dallas, Texas, USA.
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22
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Dewenter M, von der Lieth A, Katus HA, Backs J. Calcium Signaling and Transcriptional Regulation in Cardiomyocytes. Circ Res 2017; 121:1000-1020. [DOI: 10.1161/circresaha.117.310355] [Citation(s) in RCA: 110] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Calcium (Ca
2+
) is a universal regulator of various cellular functions. In cardiomyocytes, Ca
2+
is the central element of excitation–contraction coupling, but also impacts diverse signaling cascades and influences the regulation of gene expression, referred to as excitation–transcription coupling. Disturbances in cellular Ca
2+
-handling and alterations in Ca
2+
-dependent gene expression patterns are pivotal characteristics of failing cardiomyocytes, with several excitation–transcription coupling pathways shown to be critically involved in structural and functional remodeling processes. Thus, targeting Ca
2+
-dependent transcriptional pathways might offer broad therapeutic potential. In this article, we (1) review cytosolic and nuclear Ca
2+
dynamics in cardiomyocytes with respect to their impact on Ca
2+
-dependent signaling, (2) give an overview on Ca
2+
-dependent transcriptional pathways in cardiomyocytes, and (3) discuss implications of excitation–transcription coupling in the diseased heart.
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Affiliation(s)
- Matthias Dewenter
- From the Department of Molecular Cardiology and Epigenetics (M.D., A.v.d.L., J.B.) and Department of Cardiology (H.A.K.), Heidelberg University, Germany; and DZHK (German Centre for Cardiovascular Research), Partner Site Heidelberg/Mannheim, Germany (M.D., A.v.d.L., H.A.K., J.B.)
| | - Albert von der Lieth
- From the Department of Molecular Cardiology and Epigenetics (M.D., A.v.d.L., J.B.) and Department of Cardiology (H.A.K.), Heidelberg University, Germany; and DZHK (German Centre for Cardiovascular Research), Partner Site Heidelberg/Mannheim, Germany (M.D., A.v.d.L., H.A.K., J.B.)
| | - Hugo A. Katus
- From the Department of Molecular Cardiology and Epigenetics (M.D., A.v.d.L., J.B.) and Department of Cardiology (H.A.K.), Heidelberg University, Germany; and DZHK (German Centre for Cardiovascular Research), Partner Site Heidelberg/Mannheim, Germany (M.D., A.v.d.L., H.A.K., J.B.)
| | - Johannes Backs
- From the Department of Molecular Cardiology and Epigenetics (M.D., A.v.d.L., J.B.) and Department of Cardiology (H.A.K.), Heidelberg University, Germany; and DZHK (German Centre for Cardiovascular Research), Partner Site Heidelberg/Mannheim, Germany (M.D., A.v.d.L., H.A.K., J.B.)
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23
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Garcia MI, Karlstaedt A, Chen JJ, Amione-Guerra J, Youker KA, Taegtmeyer H, Boehning D. Functionally redundant control of cardiac hypertrophic signaling by inositol 1,4,5-trisphosphate receptors. J Mol Cell Cardiol 2017; 112:95-103. [PMID: 28923351 DOI: 10.1016/j.yjmcc.2017.09.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Revised: 09/09/2017] [Accepted: 09/14/2017] [Indexed: 01/06/2023]
Abstract
Calcium plays an integral role to many cellular processes including contraction, energy metabolism, gene expression, and cell death. The inositol 1, 4, 5-trisphosphate receptor (IP3R) is a calcium channel expressed in cardiac tissue. There are three IP3R isoforms encoded by separate genes. In the heart, the IP3R-2 isoform is reported to being most predominant with regards to expression levels and functional significance. The functional roles of IP3R-1 and IP3R-3 in the heart are essentially unexplored despite measureable expression levels. Here we show that all three IP3Rs isoforms are expressed in both neonatal and adult rat ventricular cardiomyocytes, and in human heart tissue. The three IP3R proteins are expressed throughout the cardiomyocyte sarcoplasmic reticulum. Using isoform specific siRNA, we found that expression of all three IP3R isoforms are required for hypertrophic signaling downstream of endothelin-1 stimulation. Mechanistically, IP3Rs specifically contribute to activation of the hypertrophic program by mediating the positive inotropic effects of endothelin-1 and leading to downstream activation of nuclear factor of activated T-cells. Our findings highlight previously unidentified functions for IP3R isoforms in the heart with specific implications for hypertrophic signaling in animal models and in human disease.
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Affiliation(s)
- M Iveth Garcia
- Cell Biology Graduate Program, University of Texas Medical Branch, Galveston, TX 77555, United States; Department of Biochemistry and Molecular Biology, McGovern Medical School at UTHealth, Houston, TX 77030, United States
| | - Anja Karlstaedt
- Department of Internal Medicine, Division of Cardiology, McGovern Medical School at UTHealth, Houston, TX 77030, United States
| | - Jessica J Chen
- Department of Biochemistry and Molecular Biology, McGovern Medical School at UTHealth, Houston, TX 77030, United States
| | | | - Keith A Youker
- Houston Methodist Hospital, Houston, TX 77030, United States
| | - Heinrich Taegtmeyer
- Department of Internal Medicine, Division of Cardiology, McGovern Medical School at UTHealth, Houston, TX 77030, United States
| | - Darren Boehning
- Department of Biochemistry and Molecular Biology, McGovern Medical School at UTHealth, Houston, TX 77030, United States.
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24
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Gambardella J, Trimarco B, Iaccarino G, Santulli G. New Insights in Cardiac Calcium Handling and Excitation-Contraction Coupling. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 1067:373-385. [PMID: 28956314 DOI: 10.1007/5584_2017_106] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Excitation-contraction (EC) coupling denotes the conversion of electric stimulus in mechanic output in contractile cells. Several studies have demonstrated that calcium (Ca2+) plays a pivotal role in this process. Here we present a comprehensive and updated description of the main systems involved in cardiac Ca2+ handling that ensure a functional EC coupling and their pathological alterations, mainly related to heart failure.
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Affiliation(s)
- Jessica Gambardella
- Department of Advanced Biomedical Sciences, "Federico II" University, Naples, Italy.,Department of Medicine, Surgery and Dentistry, Scuola Medica Salernitana, University of Salerno, Fisciano, Italy
| | - Bruno Trimarco
- Department of Advanced Biomedical Sciences, "Federico II" University, Naples, Italy
| | - Guido Iaccarino
- Department of Medicine, Surgery and Dentistry, Scuola Medica Salernitana, University of Salerno, Fisciano, Italy
| | - Gaetano Santulli
- Department of Advanced Biomedical Sciences, "Federico II" University, Naples, Italy. .,Department of Medicine, Albert Einstein College of Medicine, 1300 Morris Park Ave, Forch 525, 10461, New York, NY, USA.
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25
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Gentemann L, Kalies S, Coffee M, Meyer H, Ripken T, Heisterkamp A, Zweigerdt R, Heinemann D. Modulation of cardiomyocyte activity using pulsed laser irradiated gold nanoparticles. BIOMEDICAL OPTICS EXPRESS 2017; 8:177-192. [PMID: 28101410 PMCID: PMC5231291 DOI: 10.1364/boe.8.000177] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Revised: 11/03/2016] [Accepted: 11/11/2016] [Indexed: 05/08/2023]
Abstract
Can photothermal gold nanoparticle mediated laser manipulation be applied to induce cardiac contraction? Based on our previous work, we present a novel concept of cell stimulation. A 532 nm picosecond laser was employed to heat gold nanoparticles on cardiomyocytes. This leads to calcium oscillations in the HL-1 cardiomyocyte cell line. As calcium is connected to the contractility, we aimed to alter the contraction rate of native and stem cell derived cardiomyocytes. A contraction rate increase was particularly observed in calcium containing buffer with neonatal rat cardiomyocytes. Consequently, the study provides conceptual ideas for a light based, nanoparticle mediated stimulation system.
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Affiliation(s)
- Lara Gentemann
- Biomedical Optics Department, Laser Zentrum Hannover e.V., Hollerithallee 8, 30419 Hannover, Germany
- Lower Saxony Centre for Biomedical Engineering, Implant Research and Development, Stadtfelddamm 34, 30625 Hannover, Germany
- These authors contributed equally to this publication and should be considered co-first authors
| | - Stefan Kalies
- Lower Saxony Centre for Biomedical Engineering, Implant Research and Development, Stadtfelddamm 34, 30625 Hannover, Germany
- Institut für Quantenoptik, Gottfried Wilhelm Leibniz Universität Hannover, Welfengarten 1, 30167 Hannover, Germany
- Cluster of Excellence REBIRTH, Hannover, Germany
- These authors contributed equally to this publication and should be considered co-first authors
| | - Michelle Coffee
- Cluster of Excellence REBIRTH, Hannover, Germany
- Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), REBIRTH - Center for Regenerative Medicine, Department of Cardiothoracic, Transplantation and Vascular Surgery, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Heiko Meyer
- Biomedical Optics Department, Laser Zentrum Hannover e.V., Hollerithallee 8, 30419 Hannover, Germany
| | - Tammo Ripken
- Biomedical Optics Department, Laser Zentrum Hannover e.V., Hollerithallee 8, 30419 Hannover, Germany
| | - Alexander Heisterkamp
- Biomedical Optics Department, Laser Zentrum Hannover e.V., Hollerithallee 8, 30419 Hannover, Germany
- Lower Saxony Centre for Biomedical Engineering, Implant Research and Development, Stadtfelddamm 34, 30625 Hannover, Germany
- Institut für Quantenoptik, Gottfried Wilhelm Leibniz Universität Hannover, Welfengarten 1, 30167 Hannover, Germany
- Cluster of Excellence REBIRTH, Hannover, Germany
| | - Robert Zweigerdt
- Cluster of Excellence REBIRTH, Hannover, Germany
- Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), REBIRTH - Center for Regenerative Medicine, Department of Cardiothoracic, Transplantation and Vascular Surgery, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Dag Heinemann
- Biomedical Optics Department, Laser Zentrum Hannover e.V., Hollerithallee 8, 30419 Hannover, Germany
- Lower Saxony Centre for Biomedical Engineering, Implant Research and Development, Stadtfelddamm 34, 30625 Hannover, Germany
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Garcia MI, Boehning D. Cardiac inositol 1,4,5-trisphosphate receptors. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2016; 1864:907-914. [PMID: 27884701 DOI: 10.1016/j.bbamcr.2016.11.017] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Revised: 11/16/2016] [Accepted: 11/16/2016] [Indexed: 10/20/2022]
Abstract
Calcium is a second messenger that regulates almost all cellular functions. In cardiomyocytes, calcium plays an integral role in many functions including muscle contraction, gene expression, and cell death. Inositol 1,4,5-trisphosphate receptors (IP3Rs) are a family of calcium channels that are ubiquitously expressed in all tissues. In the heart, IP3Rs have been associated with regulation of cardiomyocyte function in response to a variety of neurohormonal agonists, including those implicated in cardiac disease. Notably, IP3R activity is thought to be essential for mediating the hypertrophic response to multiple stimuli including endothelin-1 and angiotensin II. In this review, we will explore the functional implications of IP3R activity in the heart in health and disease.
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Affiliation(s)
- M Iveth Garcia
- Cell Biology Graduate Program, University of Texas Medical Branch, Galveston, TX 77555, United States; Department of Biochemistry and Molecular Biology, McGovern Medical School at UTHealth, Houston, TX 77030, United States
| | - Darren Boehning
- Department of Biochemistry and Molecular Biology, McGovern Medical School at UTHealth, Houston, TX 77030, United States.
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Phospholamban is concentrated in the nuclear envelope of cardiomyocytes and involved in perinuclear/nuclear calcium handling. J Mol Cell Cardiol 2016; 100:1-8. [PMID: 27642167 DOI: 10.1016/j.yjmcc.2016.09.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2016] [Revised: 08/26/2016] [Accepted: 09/13/2016] [Indexed: 11/20/2022]
Abstract
AIMS Phospholamban (PLB) regulates the cardiac Ca2+-ATPase (SERCA2a) in sarcoplasmic reticulum (SR). However, the localization of PLB at subcellular sites outside the SR and possible contributions to Ca2+ cycling remain unknown. We examined the intracellular distribution of PLB and tested whether a pool of PLB exists in the nuclear envelope (NE) that might regulate perinuclear/nuclear Ca2+ (nCa2+) handling in cardiomyocytes (CMs). METHODS AND RESULTS Using confocal immunofluorescence microscopy and immunoblot analyses of CMs and CM nuclei, we discovered that PLB was highly concentrated in NE. Moreover, the ratio of PLB levels to SERCA levels was greater in NE than in SR. The increased levels of PLB in NE were a consistent finding using a range of antibodies, tissue samples, and species. To address a possible role in affecting Ca2+ handling, we used Fluo-4 based confocal Ca2+ imaging, with scan-lines across cytosol and nuclei, and evaluated the effects of PLB on cytosolic and nCa2+ uptake and release in mouse CMs. In intact CMs, isoproterenol increased amplitude and decreased the decay time of Ca2+ transients not only in cytosol but also in nuclear regions. In saponin-permeabilized mouse CMs ([Ca2+]i=400nM), we measured spontaneous Ca2+ waves after specific reversal of PLB activity by addition of the Fab fragment of an anti-PLB monoclonal antibody (100μg/ml). This highly selective immunological reagent enhanced Ca2+ uptake (faster decay times) and Ca2+ release (greater intensity) in both cytosol and across the nuclear regions. CONCLUSIONS Besides SR, PLB is concentrated in NE of CMs, and may be involved in modulation of nCa2+ dynamics.
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Li A, Guo X, Xie J, Liu X, Zhang Z, Li Y, Zhang Y. Validation of biomarkers in cardiotoxicity induced by Periplocin on neonatal rat cardiomyocytes using UPLC-Q-TOF/MS combined with a support vector machine. J Pharm Biomed Anal 2016; 123:179-85. [DOI: 10.1016/j.jpba.2016.02.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Revised: 02/05/2016] [Accepted: 02/12/2016] [Indexed: 01/01/2023]
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Pretreatment with low-dose gadolinium chloride attenuates myocardial ischemia/reperfusion injury in rats. Acta Pharmacol Sin 2016; 37:453-62. [PMID: 26948086 DOI: 10.1038/aps.2015.156] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Accepted: 12/25/2015] [Indexed: 12/14/2022] Open
Abstract
AIM We have shown that low-dose gadolinium chloride (GdCl3) abolishes arachidonic acid (AA)-induced increase of cytoplasmic Ca(2+), which is known to play a crucial role in myocardial ischemia/reperfusion (I/R) injury. The present study sought to determine whether low-dose GdCl3 pretreatment protected rat myocardium against I/R injury in vitro and in vivo. METHODS Cultured neonatal rat ventricular myocytes (NRVMs) were treated with GdCl3 or nifedipine, followed by exposure to anoxia/reoxygenation (A/R). Cell apoptosis was detected; the levels of related signaling molecules were assessed. SD rats were intravenously injected with GdCl3 or nifedipine. Thirty min after the administration the rats were subjected to LAD coronary artery ligation followed by reperfusion. Infarction size, the release of serum myocardial injury markers and AA were measured; cell apoptosis and related molecules were assessed. RESULTS In A/R-treated NRVMs, pretreatment with GdCl3 (2.5, 5, 10 μmol/L) dose-dependently inhibited caspase-3 activation, death receptor-related molecules DR5/Fas/FADD/caspase-8 expression, cytochrome c release, AA release and sustained cytoplasmic Ca(2+) increases induced by exogenous AA. In I/R-treated rats, pre-administration of GdCl3 (10 mg/kg) significantly reduced the infarct size, and the serum levels of CK-MB, cardiac troponin-I, LDH and AA. Pre-administration of GdCl3 also significantly decreased the number of apoptotic cells, caspase-3 activity, death receptor-related molecules (DR5/Fas/FADD) expression and cytochrome c release in heart tissues. The positive control drug nifedipine produced comparable cardioprotective effects in vitro and in vivo. CONCLUSION Pretreatment with low-dose GdCl3 significantly attenuates I/R-induced myocardial apoptosis in rats by suppressing activation of both death receptor and mitochondria-mediated pathways.
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Hohendanner F, Maxwell JT, Blatter LA. Cytosolic and nuclear calcium signaling in atrial myocytes: IP3-mediated calcium release and the role of mitochondria. Channels (Austin) 2016; 9:129-38. [PMID: 25891132 DOI: 10.1080/19336950.2015.1040966] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
In rabbit atrial myocytes Ca signaling has unique features due to the lack of transverse (t) tubules, the spatial arrangement of mitochondria and the contribution of inositol-1,4,5-trisphosphate (IP3) receptor-induced Ca release (IICR). During excitation-contraction coupling action potential-induced elevation of cytosolic [Ca] originates in the cell periphery from Ca released from the junctional sarcoplasmic reticulum (j-SR) and then propagates by Ca-induced Ca release from non-junctional (nj-) SR toward the cell center. The subsarcolemmal region between j-SR and the first array of nj-SR Ca release sites is devoid of mitochondria which results in a rapid propagation of activation through this domain, whereas the subsequent propagation through the nj-SR network occurs at a velocity typical for a propagating Ca wave. Inhibition of mitochondrial Ca uptake with the Ca uniporter blocker Ru360 accelerates propagation and increases the amplitude of Ca transients (CaTs) originating from nj-SR. Elevation of cytosolic IP3 levels by rapid photolysis of caged IP3 has profound effects on the magnitude of subcellular CaTs with increased Ca release from nj-SR and enhanced CaTs in the nuclear compartment. IP3 uncaging restricted to the nucleus elicites 'mini'-Ca waves that remain confined to this compartment. Elementary IICR events (Ca puffs) preferentially originate in the nucleus in close physical association with membrane structures of the nuclear envelope and the nucleoplasmic reticulum. The data suggest that in atrial myocytes the nucleus is an autonomous Ca signaling domain where Ca dynamics are primarily governed by IICR.
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Key Words
- 2-APB, 2-aminoethoxydiphenyl borate
- AP, action potential
- CICR, Ca-induced Ca release
- CRU, Ca release units
- CT, central
- CaT, Ca transient
- ECC, excitation-contraction coupling
- IICR
- IICR, IP3R-induced Ca release
- IP3
- IP3R, Inositol-1,4,5-trisphosphate receptor
- LCC, L-type Ca channels
- MCU, mitochondrial Ca uniporter
- NE, nuclear envelope
- NFAT, nuclear factor of activated T cells
- NPR, nucleoplasmic reticulum
- RyR, ryanodine receptor
- SR, sarcoplasmic reticulum
- SS, subsarcolemmal
- TF50, time to half-maximal amplitude
- TZ, transition zone.
- [Ca]i, cytosolic Ca concentration
- [Ca]mito, mitochondrial Ca concentration
- atria
- excitation-contraction coupling
- j-SR, junctional SR
- mitochondria
- nj-SR, non-junctional SR
- nuclear calcium
- t-tubule, transverse tubule
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Affiliation(s)
- Felix Hohendanner
- a Department of Molecular Biophysics and Physiology ; Rush University Medical Center ; Chicago , IL USA
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Abstract
There is increasing evidence that a deficiency in vitamin D contributes to many human diseases such as Alzheimer's disease (AD), Parkinson's disease (PD), multiple sclerosis (MS), hypertension and cardiovascular disease. The ability of vitamin D to maintain healthy cells seems to depend on its role as a guardian of phenotypic stability particularly with regard to the reactive oxygen species (ROS) and Ca2+ signalling systems. Vitamin D maintains the expression of those signalling components responsible for stabilizing the low-resting state of these two signalling pathways. This vitamin D signalling stability hypothesis proposes that vitamin D, working in conjunction with klotho and Nrf2 (nuclear factor-erythroid-2-related factor 2), acts as a custodian to maintain the normal function of the ROS and Ca2+ signalling pathways. A decline in vitamin D levels will lead to an erosion of this signalling stability and may account for why so many of the major diseases in man, which have been linked to vitamin D deficiency, are associated with a dysregulation in both ROS and Ca2+ signalling.
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Abstract
Although convention dictates that G protein-coupled receptors localize to and signal at the plasma membrane, accumulating evidence suggests that G protein-coupled receptors localize to and signal at intracellular membranes, most notably the nucleus. In fact, there is now significant evidence indicating that endogenous alpha-1 adrenergic receptors (α1-ARs) localize to and signal at the nuclei in adult cardiac myocytes. Cumulatively, the data suggest that α1-ARs localize to the inner nuclear membrane, activate intranuclear signaling, and regulate physiologic function in adult cardiac myocytes. Although α1-ARs signal through Gαq, unlike other Gq-coupled receptors, α1-ARs mediate important cardioprotective functions including adaptive/physiologic hypertrophy, protection from cell death (survival signaling), positive inotropy, and preconditioning. Also unlike other Gq-coupled receptors, most, if not all, functional α1-ARs localize to the nuclei in adult cardiac myocytes, as opposed to the sarcolemma. Together, α1-AR nuclear localization and cardioprotection might suggest a novel model for compartmentalization of Gq-coupled receptor signaling in which nuclear Gq-coupled receptor signaling is cardioprotective.
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Zhang XH, Morad M. Calcium signaling in human stem cell-derived cardiomyocytes: Evidence from normal subjects and CPVT afflicted patients. Cell Calcium 2015; 59:98-107. [PMID: 26725479 DOI: 10.1016/j.ceca.2015.12.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Revised: 12/10/2015] [Accepted: 12/11/2015] [Indexed: 10/22/2022]
Abstract
Derivation of cardiomyocyte cell lines from human fibroblasts (induced pluripotent stem cells, iPSCs) has made it possible not only to investigate the electrophysiological and Ca(2+) signaling properties of these cells, but also to determine the altered electrophysiological and Ca(2+)-signaling profiles of such cells lines derived from patients expressing mutation-inducing pathologies. This approach has the potential of generating in vitro human models of cardiovascular diseases where cellular pathology can be investigated in detail and possibly specific pharmacotherapy developed. Although this approach has been applied to a number of mutations in channel proteins that cause arrhythmias, there are only few detailed reports addressing Ca(2+) signaling pathologies beyond measurements of Ca(2+) transients in intact non-voltage clamped cells. Unfortunately, full understanding of Ca(2+) signaling pathologies remains elusive, not only because of the plethora of Ca(2+) signaling proteins defects that cause arrhythmias and cardiomyopathies, but also because detailed functional properties of Ca(2+) signaling proteins are difficult to obtain. Catecholaminergic polymorphic ventricular tachycardia (CPVT1) is a malignant inherited arrhythmogenic disorder predominantly caused by mutations in the cardiac ryanodine receptor (RyR2). Thus far over 150 mutations in RyR2 have been identified that appear to cause this arrhythmia, a number of which have been expressed and studied in transgenic mice or cell-line models. The development of human iPSC-technology makes it possible to create human heart cell-lines carrying these mutations, making detailed identification of Ca(2+) signaling defects and its specific pharmacotherapy possible. In this review we shall first briefly summarize the essential characteristics of the mammalian cardiac Ca(2+) signaling, then compare them to Ca(2+) signaling phenotypes of human induced pluripotent stem cell derived cardiomyocytes (hiPSC-CM) and to those of rat neonatal cardiomyocytes, and categorize the possible variance in Ca(2+) signaling defects caused by different CPVT-inducing mutations as expressed in hiPSC-CMs.
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Affiliation(s)
- Xiao-Hua Zhang
- Cardiac Signaling Center of USC, MUSC, & Clemson University, Charleston, SC 29425, USA
| | - Martin Morad
- Cardiac Signaling Center of USC, MUSC, & Clemson University, Charleston, SC 29425, USA.
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Georgiev T, Svirin M, Jaimovich E, Fink RHA. Localized nuclear and perinuclear Ca(2+) signals in intact mouse skeletal muscle fibers. Front Physiol 2015; 6:263. [PMID: 26483696 PMCID: PMC4586431 DOI: 10.3389/fphys.2015.00263] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Accepted: 09/07/2015] [Indexed: 11/13/2022] Open
Abstract
Nuclear Ca2+ is important for the regulation of several nuclear processes such as gene expression. Localized Ca2+ signals (LCSs) in skeletal muscle fibers of mice have been mainly studied as Ca2+ release events from the sarcoplasmic reticulum. Their location with regard to cell nuclei has not been investigated. Our study is based on the hypothesis that LCSs associated with nuclei are present in skeletal muscle fibers of adult mice. Therefore, we carried out experiments addressing this question and we found novel Ca2+ signals associated with nuclei of skeletal muscle fibers (with possibly attached satellite cells). We measured localized nuclear and perinuclear Ca2+ signals (NLCSs and PLCSs) alongside cytosolic localized Ca2+ signals (CLCSs) during a hypertonic treatment. We also observed NLCSs under isotonic conditions. The NLCSs and PLCSs are Ca2+ signals in the range of micrometer [FWHM (full width at half maximum): 2.75 ± 0.27 μm (NLCSs) and 2.55 ± 0.17 μm (PLCSs), S.E.M.]. Additionally, global nuclear Ca2+ signals (NGCSs) were observed. To investigate which type of Ca2+ channels contribute to the Ca2+ signals associated with nuclei in skeletal muscle fibers, we performed measurements with the RyR blocker dantrolene, the DHPR blocker nifedipine or the IP3R blocker Xestospongin C. We observed Ca2+ signals associated with nuclei in the presence of each blocker. Nifedipine and dantrolene had an inhibitory effect on the fraction of fibers with PLCSs. The situation for the fraction of fibers with NLCSs is more complex indicating that RyR is less important for the generation of NLCSs compared to the generation of PLCSs. The fraction of fibers with NLCSs and PLCSs is not reduced in the presence of Xestospongin C. The localized perinuclear and intranuclear Ca2+ signals may be a powerful tool for the cell to regulate adaptive processes as gene expression. The intranuclear Ca2+ signals may be particularly interesting in this respect.
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Affiliation(s)
- Tihomir Georgiev
- Medical Biophysics Unit, Institut für Physiologie und Pathophysiologie, Ruprecht Karls Universität Heidelberg, Germany ; Facultad de Medicina, Center for Molecular Studies of the Cell, Universidad de Chile Santiago de Chile, Chile
| | - Mikhail Svirin
- Medical Biophysics Unit, Institut für Physiologie und Pathophysiologie, Ruprecht Karls Universität Heidelberg, Germany
| | - Enrique Jaimovich
- Facultad de Medicina, Center for Molecular Studies of the Cell, Universidad de Chile Santiago de Chile, Chile
| | - Rainer H A Fink
- Medical Biophysics Unit, Institut für Physiologie und Pathophysiologie, Ruprecht Karls Universität Heidelberg, Germany
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Berridge MJ. Vitamin D cell signalling in health and disease. Biochem Biophys Res Commun 2015; 460:53-71. [PMID: 25998734 DOI: 10.1016/j.bbrc.2015.01.008] [Citation(s) in RCA: 126] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Accepted: 01/05/2015] [Indexed: 12/13/2022]
Abstract
Vitamin D deficiency has been linked to many human diseases such as Alzheimer's disease (AD), Parkinson's disease (PD), multiple sclerosis (MS), hypertension and cardiovascular disease. A Vitamin D phenotypic stability hypothesis, which is developed in this review, attempts to describe how this vital hormone acts to maintain healthy cellular functions. This role of Vitamin D as a guardian of phenotypic stability seems to depend on its ability to maintain the redox and Ca(2+) signalling systems. It is argued that its primary action is to maintain the expression of those signalling components responsible for stabilizing the low resting state of these two signalling pathways. This phenotypic stability role is facilitated through the ability of vitamin D to increase the expression of both Nrf2 and the anti-ageing protein Klotho, which are also major regulators of Ca(2+) and redox signalling. A decline in Vitamin D levels will lead to a decline in the stability of this regulatory signalling network and may account for why so many of the major diseases in man, which have been linked to vitamin D deficiency, are associated with a dysregulation in both ROS and Ca(2+) signalling.
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Viola HM, Hool LC. Role of the cytoskeleton in communication between L-type Ca(2+) channels and mitochondria. Clin Exp Pharmacol Physiol 2015; 40:295-304. [PMID: 23551128 DOI: 10.1111/1440-1681.12072] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2013] [Revised: 02/25/2013] [Accepted: 02/26/2013] [Indexed: 12/15/2022]
Abstract
The L-type Ca(2+) channel is the main route for Ca(2+) entry into cardiac myocytes, which is essential for the maintenance of cardiac excitation and contraction. Alterations in L-type Ca(2+) channel activity and Ca(2+) homeostasis have been implicated in the development of cardiomyopathies. Cardiac excitation and contraction is fuelled by ATP, synthesized predominantly by the mitochondria via the Ca(2+)-dependent process oxidative phosphorylation. Mitochondrial reactive oxygen species (ROS) are by-products of oxidative phosphorylation and are associated with the development of cardiac pathology. The cytoskeleton plays a role in the communication of signals from the plasma membrane to intracellular organelles. There is good evidence that both L-type Ca(2+) channel activity and mitochondrial function can be modulated by changes in the cytoskeletal network. Activation of the L-type Ca(2+) channel can regulate mitochondrial function through cytoskeletal proteins as a result of transmission of movement from the β(2)-subunit of the channel that occurs during activation and inactivation of the channel. An association between cytoskeletal proteins and the mitochondrial voltage-dependent anion channel (VDAC) may play a role in this response. The L-type Ca(2+) channel is the initiator of contraction in cardiac muscle and the VDAC is responsible for regulating mitochondrial ATP/ADP trafficking. This article presents evidence that a functional coupling between L-type Ca(2+) channels and mitochondria may assist in meeting myocardial energy demand on a beat-to-beat basis.
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Affiliation(s)
- Helena M Viola
- Cardiovascular Electrophysiology Laboratory, School of Anatomy, Physiology and Human Biology, The University of Western Australia, Crawley, WA, Australia
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Gap Junction-associated Na+ Influx Is Involved in the Mediation of Ca2+ Transients in Neonatal Rat Ventricular Myocytes. J Cardiovasc Pharmacol 2015; 66:41-9. [DOI: 10.1097/fjc.0000000000000241] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Zhao T, Zhao W, Meng W, Liu C, Chen Y, Gerling IC, Weber KT, Bhattacharya SK, Kumar R, Sun Y. VEGF-C/VEGFR-3 pathway promotes myocyte hypertrophy and survival in the infarcted myocardium. Am J Transl Res 2015; 7:697-709. [PMID: 26064438 PMCID: PMC4455345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Accepted: 04/11/2015] [Indexed: 06/04/2023]
Abstract
BACKGROUND Numerous studies have shown that in addition to angio/lymphangiogenesis, the VEGF family is involved in other cellular actions. We have recently reported that enhanced VEGF-C and VEGFR-3 in the infarcted rat myocardium, suggesting the paracrine/autocrine function of VEGF-C on cardiac remodeling. The current study was designed to test the hypothesis that VEGF-C regulates cardiomyocyte growth and survival in the infarcted myocardium. METHODS AND RESULTS Gene profiling and VEGFR-3 expression of cardiomyocytes were assessed by laser capture microdissection/microarray and immunohistochemistry in the normal and infarcted myocardium. The effect of VEGF-C on myocyte hypertrophy and apoptosis during normoxia and hypoxia was detected by RT-PCR and western blotting in cultured rat neonatal cardiomyocytes. VEGFR-3 was minimally expressed in cardiomyocytes of the normal and noninfarcted myocardium, while markedly elevated in the surviving cardiomyocytes of the infarcted myocardium and border zone. Genes altered in the surviving cardiomyocytes were associated with the networks regulating cellular growth and survival. VEGF-C significantly increased the expression of atrial natriuretic factor (ANP), brain natriuretic factor (BNP), and β-myosin heavy chain (MHC), markers of hypertrophy, in neonatal cardiomyocytes. Hypoxia caused neonatal cardiomyocyte atrophy, which was prevented by VEGF-C treatment. Hypoxia significantly enhanced apoptotic mediators, including cleaved caspase 3, 8, and 9, and Bax in neonatal cardiomyocytes, which were abolished by VEGF-C treatment. CONCLUSION Our findings indicate that VEGF-C/VEGFR-3 pathway exerts a beneficial role in the infarcted myocardium by promoting compensatory cardiomyocyte hypertrophy and survival.
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Affiliation(s)
- Tieqiang Zhao
- Division of Cardiovascular Diseases, Department of Medicine, University of Tennessee Health Science CenterMemphis, TN 38163, USA
| | - Wenyuan Zhao
- Division of Cardiovascular Diseases, Department of Medicine, University of Tennessee Health Science CenterMemphis, TN 38163, USA
| | - Weixin Meng
- Division of Cardiovascular Diseases, Department of Medicine, University of Tennessee Health Science CenterMemphis, TN 38163, USA
| | - Chang Liu
- Division of Cardiovascular Diseases, Department of Medicine, University of Tennessee Health Science CenterMemphis, TN 38163, USA
| | - Yuanjian Chen
- Division of Cardiovascular Diseases, Department of Medicine, University of Tennessee Health Science CenterMemphis, TN 38163, USA
| | - Ivan C Gerling
- Division of Endocrinology, Department of Medicine, University of Tennessee Health Science CenterMemphis, TN 38163, USA
| | - Karl T Weber
- Division of Cardiovascular Diseases, Department of Medicine, University of Tennessee Health Science CenterMemphis, TN 38163, USA
| | - Syamal K Bhattacharya
- Division of Cardiovascular Diseases, Department of Medicine, University of Tennessee Health Science CenterMemphis, TN 38163, USA
| | - Rahul Kumar
- Division of Cardiovascular Diseases, Department of Medicine, University of Tennessee Health Science CenterMemphis, TN 38163, USA
| | - Yao Sun
- Division of Cardiovascular Diseases, Department of Medicine, University of Tennessee Health Science CenterMemphis, TN 38163, USA
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Wu SC, Dahl EF, Wright CD, Cypher AL, Healy CL, O'Connell TD. Nuclear localization of a1A-adrenergic receptors is required for signaling in cardiac myocytes: an “inside-out” a1-AR signaling pathway. J Am Heart Assoc 2014; 3:e000145. [PMID: 24772522 PMCID: PMC4187477 DOI: 10.1161/jaha.113.000145] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Background Recent studies indicate that α1‐adrenergic receptors (α1‐ARs) are cardioprotective by preventing cardiac myocyte death and augmenting contractility in heart failure. Although G‐protein‐coupled receptors are assumed to localize to and signal at the plasma membrane, we previously demonstrated that endogenous α1‐ARs localize to the nuclei in adult cardiac myocytes. However, the functional consequence of this nuclear localization remains unclear. Here, we attempted to reconcile nuclear localization of α1‐ARs with their physiologic function by examining α1‐AR‐induced contractility in adult cardiac myocytes. Methods and Results By measuring shortening in unloaded, cultured adult cardiac myocytes, we found that the α1A‐subtype regulated contractility through phosphorylation of cardiac troponin I (cTnI) at the protein kinase C (PKC) site, threonine 144. Reconstitution of an α1A‐subtype nuclear localization mutant in cardiac myocytes lacking α1‐ARs failed to rescue nuclear α1A‐mediated phosphorylation of cTnI and myocyte contractility. Leptomycin B, the nuclear export inhibitor, also blocked α1A‐mediated phosphorylation of cTnI. These data indicate that α1‐AR signaling originates in the nucleus. Consistent with these observations, we localized the α1A‐subtype to the inner nuclear membrane, identified PKCα, δ, and ε in the nucleus, and found that α1‐ARs activate PKCδ in nuclei isolated from adult cardiac myocytes. Finally, we found that a PKCδ nuclear localization mutant blunted α1‐induced phosphorylation of cTnI. Conclusions Together, our data identify a novel, “inside‐out” nuclear α1A‐subtype/PKCδ/cTnI‐signaling pathway that regulates contractile function in adult cardiac myocytes. Importantly, these data help resolve the discrepancy between nuclear localization of α1‐ARs and α1‐AR‐mediated physiologic function.
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Affiliation(s)
- Steven C. Wu
- Department of Integrative Biology and Physiology, The University of Minnesota, Minneapolis, MN (S.C.W., E.F.D., C.D.W., A.L.C., C.L.H., T.D.C.)
| | - Erika F. Dahl
- Department of Integrative Biology and Physiology, The University of Minnesota, Minneapolis, MN (S.C.W., E.F.D., C.D.W., A.L.C., C.L.H., T.D.C.)
| | - Casey D. Wright
- Department of Integrative Biology and Physiology, The University of Minnesota, Minneapolis, MN (S.C.W., E.F.D., C.D.W., A.L.C., C.L.H., T.D.C.)
- Novartis Animal Health US, Inc, 1447140th St, Larchwood, IA 51241
| | - Andrew L. Cypher
- Department of Integrative Biology and Physiology, The University of Minnesota, Minneapolis, MN (S.C.W., E.F.D., C.D.W., A.L.C., C.L.H., T.D.C.)
- Novartis Animal Health US, Inc, 1447140th St, Larchwood, IA 51241
| | - Chastity L. Healy
- Department of Integrative Biology and Physiology, The University of Minnesota, Minneapolis, MN (S.C.W., E.F.D., C.D.W., A.L.C., C.L.H., T.D.C.)
| | - Timothy D. O'Connell
- Department of Integrative Biology and Physiology, The University of Minnesota, Minneapolis, MN (S.C.W., E.F.D., C.D.W., A.L.C., C.L.H., T.D.C.)
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Ibarra C, Vicencio JM, Varas-Godoy M, Jaimovich E, Rothermel BA, Uhlén P, Hill JA, Lavandero S. An integrated mechanism of cardiomyocyte nuclear Ca(2+) signaling. J Mol Cell Cardiol 2014; 75:40-8. [PMID: 24997440 PMCID: PMC4626248 DOI: 10.1016/j.yjmcc.2014.06.015] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Revised: 06/11/2014] [Accepted: 06/26/2014] [Indexed: 01/05/2023]
Abstract
In cardiomyocytes, Ca(2+) plays a central role in governing both contraction and signaling events that regulate gene expression. Current evidence indicates that discrimination between these two critical functions is achieved by segregating Ca(2+) within subcellular microdomains: transcription is regulated by Ca(2+) release within nuclear microdomains, and excitation-contraction coupling is regulated by cytosolic Ca(2+). Accordingly, a variety of agonists that control cardiomyocyte gene expression, such as endothelin-1, angiotensin-II or insulin-like growth factor-1, share the feature of triggering nuclear Ca(2+) signals. However, signaling pathways coupling surface receptor activation to nuclear Ca(2+) release, and the phenotypic responses to such signals, differ between agonists. According to earlier hypotheses, the selective control of nuclear Ca(2+) signals by activation of plasma membrane receptors relies on the strategic localization of inositol trisphosphate receptors at the nuclear envelope. There, they mediate Ca(2+) release from perinuclear Ca(2+) stores upon binding of inositol trisphosphate generated in the cytosol, which diffuses into the nucleus. More recently, identification of such receptors at nuclear membranes or perinuclear sarcolemmal invaginations has uncovered novel mechanisms whereby agonists control nuclear Ca(2+) release. In this review, we discuss mechanisms for the selective control of nuclear Ca(2+) signals with special focus on emerging models of agonist receptor activation.
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Affiliation(s)
- Cristián Ibarra
- Cardiovascular and Metabolic Diseases, Innovative Medicines and Early Development, AstraZeneca R&D, Mölndal, Sweden.
| | - Jose Miguel Vicencio
- Hatter Cardiovascular Institute, University College London, London, United Kingdom
| | - Manuel Varas-Godoy
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Enrique Jaimovich
- Centro de Estudios Moleculares de la Célula, Facultad de Ciencias Químicas y Farmacéuticas & Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Beverly A Rothermel
- Department of Internal Medicine, Cardiology Division, University of Texas Southwestern Medical Center, Dallas, TX, USA; Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Per Uhlén
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Joseph A Hill
- Department of Internal Medicine, Cardiology Division, University of Texas Southwestern Medical Center, Dallas, TX, USA; Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Sergio Lavandero
- Centro de Estudios Moleculares de la Célula, Facultad de Ciencias Químicas y Farmacéuticas & Facultad de Medicina, Universidad de Chile, Santiago, Chile; Department of Internal Medicine, Cardiology Division, University of Texas Southwestern Medical Center, Dallas, TX, USA; Advanced Center for Chronic Diseases, Facultad de Ciencias Químicas y Farmacéuticas & Facultad de Medicina, Universidad de Chile, Santiago, Chile.
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Kang M, Lin N, Li C, Meng Q, Zheng Y, Yan X, Deng J, Ou Y, Zhang C, He J, Luo D. Cx43 phosphorylation on S279/282 and intercellular communication are regulated by IP3/IP3 receptor signaling. Cell Commun Signal 2014; 12:58. [PMID: 25262337 PMCID: PMC4195880 DOI: 10.1186/s12964-014-0058-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Accepted: 09/11/2014] [Indexed: 11/17/2022] Open
Abstract
Background Inositol 1,4,5-trisphosphate receptor (IP3R) plays a pivotal role in the Ca2+ release process in a variety of cell types. Additionally, IP3R is distributed in ventricular intercalated discs, but its function(s) in this particular site remains unknown. Connexin (Cx43), the predominant gap junction (GJ) protein in ventricular myocardium, is linked to several signaling pathways that regulate Cx43 properties by (de)phosphorylation on multiple residues. Here, we investigated the regulatory role of IP3R in cell-cell communication and the mechanism(s) underlying this effect. Results In neonatal rat and adult mouse ventricular myocytes IP3R co-localized and co-immunoprecipitated with Cx43 in GJ plaques detected by immunostaining and western blot assays. Blocking IP3R with antagonists or silencing pan-IP3R expression with shRNA hindered the 6-carboxyfluorescein (6-CFDA) diffusion through GJs and desynchronized Ca2+ transients among confluent neonatal myocytes in culture, whereas stimulation of IP3R with IP3 ester or ATP exerted the opposite effect. Likewise, 6-CFDA propagation through GJs was modulated by IP3R activation or inhibition in cell pairs of isolated adult cardiomyocytes. Furthermore, IP3R activation or IP3R suppression promoted or suppressed, respectively, Cx43 phosphorylation on S279/282. Site-directed mutagenesis indicated that expression of a mutant Cx43-S282A (alanine) inhibited S279/282 phosphorylation and GJ permeability, while the S279A mutant showed the opposite effect in ventricular myocytes. Expression of these mutants in HEK293 cells revealed that cells with a dual S279/282 mutation failed to express exogenous Cx43, whereas cells with a single S279 or S282 mutation displayed Cx43 overexpression with increased phosphorylation of S279/282 and promotion of intercellular communication. Conclusions These results demonstrated, for the first time, that IP3R physically interacts with Cx43 and participates in the regulation of Cx43 phosphorylation on S279/282, thereby affecting GJ intercellular communication in ventricular myocytes. Electronic supplementary material The online version of this article (doi:10.1186/s12964-014-0058-6) contains supplementary material, which is available to authorized users.
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Camors E, Valdivia HH. CaMKII regulation of cardiac ryanodine receptors and inositol triphosphate receptors. Front Pharmacol 2014; 5:101. [PMID: 24847270 PMCID: PMC4021131 DOI: 10.3389/fphar.2014.00101] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Accepted: 04/17/2014] [Indexed: 01/08/2023] Open
Abstract
Ryanodine receptors (RyRs) and inositol triphosphate receptors (InsP3Rs) are structurally related intracellular calcium release channels that participate in multiple primary or secondary amplified Ca(2+) signals, triggering muscle contraction and oscillatory Ca(2+) waves, or activating transcription factors. In the heart, RyRs play an indisputable role in the process of excitation-contraction coupling as the main pathway for Ca(2+) release from sarcoplasmic reticulum (SR), and a less prominent role in the process of excitation-transcription coupling. Conversely, InsP3Rs are believed to contribute in subtle ways, only, to contraction of the heart, and in more important ways to regulation of transcription factors. Because uncontrolled activity of either RyRs or InsP3Rs may elicit life-threatening arrhythmogenic and/or remodeling Ca(2+) signals, regulation of their activity is of paramount importance for normal cardiac function. Due to their structural similarity, many regulatory factors, accessory proteins, and post-translational processes are equivalent for RyRs and InsP3Rs. Here we discuss regulation of RyRs and InsP3Rs by CaMKII phosphorylation, but touch on other kinases whenever appropriate. CaMKII is emerging as a powerful modulator of RyR and InsP3R activity but interestingly, some of the complexities and controversies surrounding phosphorylation of RyRs also apply to InsP3Rs, and a clear-cut effect of CaMKII on either channel eludes investigators for now. Nevertheless, some effects of CaMKII on global cellular activity, such as SR Ca(2+) leak or force-frequency potentiation, appear clear now, and this constrains the limits of the controversies and permits a more tractable approach to elucidate the effects of phosphorylation at the single channel level.
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Affiliation(s)
- Emmanuel Camors
- Division of Cardiovascular Medicine, Department of Internal Medicine, Center for Arrhythmia Research, University of Michigan, Ann Arbor MI, USA
| | - Héctor H Valdivia
- Division of Cardiovascular Medicine, Department of Internal Medicine, Center for Arrhythmia Research, University of Michigan, Ann Arbor MI, USA
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Kapoor N, Maxwell JT, Mignery GA, Will D, Blatter LA, Banach K. Spatially defined InsP3-mediated signaling in embryonic stem cell-derived cardiomyocytes. PLoS One 2014; 9:e83715. [PMID: 24409283 PMCID: PMC3883750 DOI: 10.1371/journal.pone.0083715] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Accepted: 11/06/2013] [Indexed: 11/19/2022] Open
Abstract
The functional role of inositol 1,4,5-trisphosphate (InsP3) signaling in cardiomyocytes is not entirely understood but it was linked to an increased propensity for triggered activity. The aim of this study was to determine how InsP3 receptors can translate Ca(2+) release into a depolarization of the plasma membrane and consequently arrhythmic activity. We used embryonic stem cell-derived cardiomyocytes (ESdCs) as a model system since their spontaneous electrical activity depends on InsP3-mediated Ca(2+) release. [InsP3]i was monitored with the FRET-based InsP3-biosensor FIRE-1 (Fluorescent InsP3 Responsive Element) and heterogeneity in sub-cellular [InsP3]i was achieved by targeted expression of FIRE-1 in the nucleus (FIRE-1nuc) or expression of InsP3 5-phosphatase (m43) localized to the plasma membrane. Spontaneous activity of ESdCs was monitored simultaneously as cytosolic Ca(2+) transients (Fluo-4/AM) and action potentials (current clamp). During diastole, the diastolic depolarization was paralleled by an increase of [Ca(2+)]i and spontaneous activity was modulated by [InsP3]i. A 3.7% and 1.7% increase of FIRE-1 FRET ratio and 3.0 and 1.5 fold increase in beating frequency was recorded upon stimulation with endothelin-1 (ET-1, 100 nmol/L) or phenylephrine (PE, 10 µmol/L), respectively. Buffering of InsP3 by FIRE-1nuc had no effect on the basal frequency while attenuation of InsP3 signaling throughout the cell (FIRE-1), or at the plasma membrane (m43) resulted in a 53.7% and 54.0% decrease in beating frequency. In m43 expressing cells the response to ET-1 was completely suppressed. Ca(2+) released from InsP3Rs is more effective than Ca(2+) released from RyRs to enhance INCX. The results support the hypothesis that in ESdCs InsP3Rs form a functional signaling domain with NCX that translates Ca(2+) release efficiently into a depolarization of the membrane potential.
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Affiliation(s)
- Nidhi Kapoor
- Heart Institute, Cedars-Sinai Medical Center, Los Angeles, California, United States of America
| | - Joshua T. Maxwell
- Department of Molecular Biophysics and Physiology, Rush University Medical Center, Chicago, Illinois, United States of America
| | - Gregory A. Mignery
- Department of Cell and Molecular Physiology, Stritch School of Medicine, Loyola University Chicago, Maywood, Illinois, United States of America
| | - David Will
- Center for Cardiovascular Research, Dept. of Medicine, Section of Cardiology, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Lothar A. Blatter
- Department of Molecular Biophysics and Physiology, Rush University Medical Center, Chicago, Illinois, United States of America
| | - Kathrin Banach
- Center for Cardiovascular Research, Dept. of Medicine, Section of Cardiology, University of Illinois at Chicago, Chicago, Illinois, United States of America
- * E-mail:
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Zeng Z, Zhang H, Lin N, Kang M, Zheng Y, Li C, Xu P, Wu Y, Luo D. Role of Inositol-1,4,5-Trisphosphate Receptor in the Regulation of Calcium Transients in Neonatal Rat Ventricular Myocytes. J Pharmacol Sci 2014. [DOI: 10.1254/jphs.14029fp] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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45
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Li S, Cheng H, Tomaselli GF, Li RA. Mechanistic basis of excitation-contraction coupling in human pluripotent stem cell-derived ventricular cardiomyocytes revealed by Ca2+ spark characteristics: Direct evidence of functional Ca2+-induced Ca2+ release. Heart Rhythm 2014; 11:133-40. [DOI: 10.1016/j.hrthm.2013.10.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Indexed: 10/26/2022]
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46
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Zhang C, Zheng Y, Chen L, Chen M, Liang S, Lin M, Luo D. Regulation of basal lateral membrane mobility and permeability to divalent cations by membrane associated-protein kinase C. PLoS One 2013; 8:e80291. [PMID: 24260363 PMCID: PMC3832666 DOI: 10.1371/journal.pone.0080291] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2013] [Accepted: 10/01/2013] [Indexed: 11/19/2022] Open
Abstract
Biological membrane stabilization is essential for maintenance of cellular homeostasis, functionality and appropriate response to various stimuli. Previous studies have showed that accumulation of PKCs in the cell membrane significantly downregulates the membrane fluidity and Ca2+ influxes through the membranes in activated cells. In addition, membrane-inserted form of PKCs has been found in a variety of resting mammalian cells and tissues. This study is aimed to investigate possible role of the endogenous membrane-associated PKCs in the modulation of basal membrane fluidity. Here, we showed that interfering PKC expression by chronic activation of PKC with phorbol myristate acetate (PMA) or shRNA targeting at PKCα lowered the levels of PKCα in cytosol, peripheral membrane and integral membrane pools, while short-term activation of PKC with PMA induced accumulation of PKCα in the membrane pool accompanied by a dramatic decrease in the cytosol fraction. The lateral membrane mobility increased or decreased in accordance with the abundance alterations in the membrane-associated PKCα by these treatments. In addition, membrane permeability to divalent cations including Ca2+, Mn2+ and Ba2+ were also potentiated or abrogated along with the changes in PKC expression on the plasma membrane. Membrane stabilizer ursodeoxycholate abolished both of the enhanced lateral membrane mobility and permeability to divalent cations due to PKCα deficiency, whereas Gö6983, a PKC antagonist, or Gd3+ and 2-aminoethyoxydipheyl borne, two Ca2+ channels blockers, showed no effect, suggesting that this PKC-related regulation is independent of PKC activation or a modulation of specific divalent cation channel. Thus, these data demonstrate that the native membrane-associated PKCα is involved in the maintenance of basal membrane stabilization in resting cells.
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Affiliation(s)
- Chao Zhang
- Department of Pharmacology, School of Chemical Biology & Pharmaceutical Sciences, Capital Medical University, Beijing, P.R. China
| | - Yuanyuan Zheng
- Department of Pharmacology, School of Chemical Biology & Pharmaceutical Sciences, Capital Medical University, Beijing, P.R. China
| | - Lihong Chen
- Department of Pharmacology, School of Chemical Biology & Pharmaceutical Sciences, Capital Medical University, Beijing, P.R. China
| | - Min Chen
- Department of Pharmacology, School of Chemical Biology & Pharmaceutical Sciences, Capital Medical University, Beijing, P.R. China
| | - Shenxuan Liang
- Department of Pharmacology, School of Chemical Biology & Pharmaceutical Sciences, Capital Medical University, Beijing, P.R. China
| | - Mosi Lin
- Department of Pharmacology, School of Chemical Biology & Pharmaceutical Sciences, Capital Medical University, Beijing, P.R. China
| | - Dali Luo
- Department of Pharmacology, School of Chemical Biology & Pharmaceutical Sciences, Capital Medical University, Beijing, P.R. China
- * E-mail:
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47
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Calcium sensing receptor regulates cardiomyocyte function through nuclear calcium. Cell Biol Int 2013; 36:937-43. [PMID: 22708524 DOI: 10.1042/cbi20110594] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Nuclear Ca(2+) plays a pivotal role in the regulation of gene expression. IP3 (inositol-1,4,5-trisphosphate) is an important regulator of nuclear Ca(2+). We hypothesized that the CaR (calcium sensing receptor) stimulates nuclear Ca(2+) release through IICR (IP3-induced calcium release) from perinuclear stores. Spontaneous Ca(2+) oscillations and the spark frequency of nuclear Ca(2+) were measured simultaneously in NRVMs (neonatal rat ventricular myocytes) using confocal imaging. CaR-induced nuclear Ca(2+) release through IICR was abolished by inhibition of CaR and IP3Rs (IP3 receptors). However, no effect on the inhibition of RyRs (ryanodine receptors) was detected. The results suggest that CaR specifically modulates nuclear Ca(2+) signalling through the IP(3)R pathway. Interestingly, nuclear Ca(2+) was released from perinuclear stores by CaR activator-induced cardiomyocyte hypertrophy through the Ca(2+)-dependent phosphatase CaN (calcineurin)/NFAT (nuclear factor of activated T-cells) pathway. We have also demonstrated that the activation of the CaR increased the NRVM protein content, enlarged cell size and stimulated CaN expression and NFAT nuclear translocation in NRVMs. Thus, CaR enhances the nuclear Ca(2+) transient in NRVMs by increasing fractional Ca(2+) release from perinuclear stores, which is involved in cardiac hypertrophy through the CaN/NFAT pathway.
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48
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Cellular Calcium. Mol Pharmacol 2012. [DOI: 10.1002/9781118451908.ch9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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49
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Drawnel FM, Wachten D, Molkentin JD, Maillet M, Aronsen JM, Swift F, Sjaastad I, Liu N, Catalucci D, Mikoshiba K, Hisatsune C, Okkenhaug H, Andrews SR, Bootman MD, Roderick HL. Mutual antagonism between IP(3)RII and miRNA-133a regulates calcium signals and cardiac hypertrophy. J Cell Biol 2012; 199:783-98. [PMID: 23166348 PMCID: PMC3514786 DOI: 10.1083/jcb.201111095] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2011] [Accepted: 10/25/2012] [Indexed: 11/22/2022] Open
Abstract
Inositol 1,4,5'-triphosphate receptor II (IP(3)RII) calcium channel expression is increased in both hypertrophic failing human myocardium and experimentally induced models of the disease. The ectopic calcium released from these receptors induces pro-hypertrophic gene expression and may promote arrhythmias. Here, we show that IP(3)RII expression was constitutively restrained by the muscle-specific miRNA, miR-133a. During the hypertrophic response to pressure overload or neurohormonal stimuli, miR-133a down-regulation permitted IP(3)RII levels to increase, instigating pro-hypertrophic calcium signaling and concomitant pathological remodeling. Using a combination of in vivo and in vitro approaches, we demonstrated that IP(3)-induced calcium release (IICR) initiated the hypertrophy-associated decrease in miR-133a. In this manner, hypertrophic stimuli that engage IICR set a feed-forward mechanism in motion whereby IICR decreased miR-133a expression, further augmenting IP(3)RII levels and therefore pro-hypertrophic calcium release. Consequently, IICR can be considered as both an initiating event and a driving force for pathological remodeling.
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Affiliation(s)
- Faye M. Drawnel
- Babraham Institute, Babraham, Cambridge CB22 3AT, England, UK
| | - Dagmar Wachten
- Babraham Institute, Babraham, Cambridge CB22 3AT, England, UK
- Department of Molecular Sensory Systems, Center of Advanced European Studies and Research, 53175 Bonn, Germany
| | - Jeffery D. Molkentin
- Department of Pediatrics, University of Cincinnati, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229
| | - Marjorie Maillet
- Department of Pediatrics, University of Cincinnati, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229
| | - Jan Magnus Aronsen
- Institute for Experimental Medical Research, Faculty of Medicine, Oslo University Hospital, 0407 Oslo, Norway
- Bjørknes College, 0456 Oslo, Norway
| | - Fredrik Swift
- Institute for Experimental Medical Research, Faculty of Medicine, Oslo University Hospital, 0407 Oslo, Norway
| | - Ivar Sjaastad
- Institute for Experimental Medical Research, Faculty of Medicine, Oslo University Hospital, 0407 Oslo, Norway
| | - Ning Liu
- Department of Molecular Biology, UT Southwestern Medical Center, Dallas, TX 75390
| | - Daniele Catalucci
- Humanitas Clinical and Research Center, 20089 Rozzano, Milan, Italy
- Institute of Genetic and Biomedical Research, Milan Section, National Research Council, 20138 Milan, Italy
| | - Katsuhiko Mikoshiba
- Laboratory for Developmental Neurobiology, RIKEN Brain Science Institute, Wako, Saitama 531-0198, Japan
| | - Chihiro Hisatsune
- Laboratory for Developmental Neurobiology, RIKEN Brain Science Institute, Wako, Saitama 531-0198, Japan
| | | | | | | | - H. Llewelyn Roderick
- Babraham Institute, Babraham, Cambridge CB22 3AT, England, UK
- Department of Pharmacology, University of Cambridge, Cambridge CB2 1PD, England, UK
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Ibarra C, Vicencio JM, Estrada M, Lin Y, Rocco P, Rebellato P, Munoz JP, Garcia-Prieto J, Quest AFG, Chiong M, Davidson SM, Bulatovic I, Grinnemo KH, Larsson O, Szabadkai G, Uhlén P, Jaimovich E, Lavandero S. Local control of nuclear calcium signaling in cardiac myocytes by perinuclear microdomains of sarcolemmal insulin-like growth factor 1 receptors. Circ Res 2012; 112:236-45. [PMID: 23118311 DOI: 10.1161/circresaha.112.273839] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
RATIONALE The ability of a cell to independently regulate nuclear and cytosolic Ca(2+) signaling is currently attributed to the differential distribution of inositol 1,4,5-trisphosphate receptor channel isoforms in the nucleoplasmic versus the endoplasmic reticulum. In cardiac myocytes, T-tubules confer the necessary compartmentation of Ca(2+) signals, which allows sarcomere contraction in response to plasma membrane depolarization, but whether there is a similar structure tunneling extracellular stimulation to control nuclear Ca(2+) signals locally has not been explored. OBJECTIVE To study the role of perinuclear sarcolemma in selective nuclear Ca(2+) signaling. METHODS AND RESULTS We report here that insulin-like growth factor 1 triggers a fast and independent nuclear Ca(2+) signal in neonatal rat cardiac myocytes, human embryonic cardiac myocytes, and adult rat cardiac myocytes. This fast and localized response is achieved by activation of insulin-like growth factor 1 receptor signaling complexes present in perinuclear invaginations of the plasma membrane. The perinuclear insulin-like growth factor 1 receptor pool connects extracellular stimulation to local activation of nuclear Ca(2+) signaling and transcriptional upregulation through the perinuclear hydrolysis of phosphatidylinositol 4,5-biphosphate inositol 1,4,5-trisphosphate production, nuclear Ca(2+) release, and activation of the transcription factor myocyte-enhancing factor 2C. Genetically engineered Ca(2+) buffers--parvalbumin--with cytosolic or nuclear localization demonstrated that the nuclear Ca(2+) handling system is physically and functionally segregated from the cytosolic Ca(2+) signaling machinery. CONCLUSIONS These data reveal the existence of an inositol 1,4,5-trisphosphate-dependent nuclear Ca(2+) toolkit located in direct apposition to the cell surface, which allows the local control of rapid and independent activation of nuclear Ca(2+) signaling in response to an extracellular ligand.
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Affiliation(s)
- Cristian Ibarra
- Centro de Estudios Moleculares de la Célula, Facultad de Ciencias Quimicas y Farmaceuticas, Universidad de Chile, Santiago, Chile
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