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Zhu C, Yuan T, Krishnan J. Targeting cardiomyocyte cell cycle regulation in heart failure. Basic Res Cardiol 2024; 119:349-369. [PMID: 38683371 PMCID: PMC11142990 DOI: 10.1007/s00395-024-01049-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 03/11/2024] [Accepted: 03/29/2024] [Indexed: 05/01/2024]
Abstract
Heart failure continues to be a significant global health concern, causing substantial morbidity and mortality. The limited ability of the adult heart to regenerate has posed challenges in finding effective treatments for cardiac pathologies. While various medications and surgical interventions have been used to improve cardiac function, they are not able to address the extensive loss of functioning cardiomyocytes that occurs during cardiac injury. As a result, there is growing interest in understanding how the cell cycle is regulated and exploring the potential for stimulating cardiomyocyte proliferation as a means of promoting heart regeneration. This review aims to provide an overview of current knowledge on cell cycle regulation and mechanisms underlying cardiomyocyte proliferation in cases of heart failure, while also highlighting established and novel therapeutic strategies targeting this area for treatment purposes.
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Affiliation(s)
- Chaonan Zhu
- Department of Medicine III, Cardiology/Angiology/Nephrology, Goethe University Hospital, 60590, Frankfurt am Main, Germany
- Institute for Cardiovascular Regeneration, Goethe University, 60590, Frankfurt am Main, Germany
| | - Ting Yuan
- Department of Medicine III, Cardiology/Angiology/Nephrology, Goethe University Hospital, 60590, Frankfurt am Main, Germany.
- Institute for Cardiovascular Regeneration, Goethe University, 60590, Frankfurt am Main, Germany.
- German Center for Cardiovascular Research, Partner Site Rhein-Main, 60590, Frankfurt am Main, Germany.
- Cardio-Pulmonary Institute, Goethe University Hospital, 60590, Frankfurt am Main, Germany.
| | - Jaya Krishnan
- Department of Medicine III, Cardiology/Angiology/Nephrology, Goethe University Hospital, 60590, Frankfurt am Main, Germany.
- Institute for Cardiovascular Regeneration, Goethe University, 60590, Frankfurt am Main, Germany.
- German Center for Cardiovascular Research, Partner Site Rhein-Main, 60590, Frankfurt am Main, Germany.
- Cardio-Pulmonary Institute, Goethe University Hospital, 60590, Frankfurt am Main, Germany.
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2
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Poveda J, González-Lafuente L, Vázquez-Sánchez S, Mercado-García E, Rodríguez-Sánchez E, García-Consuegra I, Sanz AB, Segura J, Fernández-Velasco M, Liaño F, Ruilope LM, Ruiz-Hurtado G. Targeting the TWEAK-Fn14 pathway prevents dysfunction in cardiac calcium handling after acute kidney injury. J Pathol 2023; 261:427-441. [PMID: 37776271 DOI: 10.1002/path.6200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 07/07/2023] [Accepted: 08/11/2023] [Indexed: 10/02/2023]
Abstract
Heart and kidney have a closely interrelated pathophysiology. Acute kidney injury (AKI) is associated with significantly increased rates of cardiovascular events, a relationship defined as cardiorenal syndrome type 3 (CRS3). The underlying mechanisms that trigger heart disease remain, however, unknown, particularly concerning the clinical impact of AKI on cardiac outcomes and overall mortality. Tumour necrosis factor-like weak inducer of apoptosis (TWEAK) and its receptor fibroblast growth factor-inducible 14 (Fn14) are independently involved in the pathogenesis of both heart and kidney failure, and recent studies have proposed TWEAK as a possible therapeutic target; however, its specific role in cardiac damage associated with CRS3 remains to be clarified. Firstly, we demonstrated in a retrospective longitudinal clinical study that soluble TWEAK plasma levels were a predictive biomarker of mortality in patients with AKI. Furthermore, the exogenous application of TWEAK to native ventricular cardiomyocytes induced relevant calcium (Ca2+ ) handling alterations. Next, we investigated the role of the TWEAK-Fn14 axis in cardiomyocyte function following renal ischaemia-reperfusion (I/R) injury in mice. We observed that TWEAK-Fn14 signalling was activated in the hearts of AKI mice. Mice also showed significantly altered intra-cardiomyocyte Ca2+ handling and arrhythmogenic Ca2+ events through an impairment in sarcoplasmic reticulum Ca2+ -adenosine triphosphatase 2a pump (SERCA2a ) and ryanodine receptor (RyR2 ) function. Administration of anti-TWEAK antibody after reperfusion significantly improved alterations in Ca2+ cycling and arrhythmogenic events and prevented SERCA2a and RyR2 modifications. In conclusion, this study establishes the relevance of the TWEAK-Fn14 pathway in cardiac dysfunction linked to CRS3, both as a predictor of mortality in patients with AKI and as a Ca2+ mishandling inducer in cardiomyocytes, and highlights the cardioprotective benefits of TWEAK targeting in CRS3. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.
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Affiliation(s)
- Jonay Poveda
- Cardiorenal Translational Laboratory, Institute of Research Imas12, Hospital Universitario 12 de Octubre, Madrid, Spain
| | - Laura González-Lafuente
- Cardiorenal Translational Laboratory, Institute of Research Imas12, Hospital Universitario 12 de Octubre, Madrid, Spain
| | - Sara Vázquez-Sánchez
- Cardiorenal Translational Laboratory, Institute of Research Imas12, Hospital Universitario 12 de Octubre, Madrid, Spain
| | - Elisa Mercado-García
- Cardiorenal Translational Laboratory, Institute of Research Imas12, Hospital Universitario 12 de Octubre, Madrid, Spain
| | - Elena Rodríguez-Sánchez
- Cardiorenal Translational Laboratory, Institute of Research Imas12, Hospital Universitario 12 de Octubre, Madrid, Spain
| | - Inés García-Consuegra
- Proteomics Unit, Institute of Research Imas12, Hospital Universitario 12 de Octubre, Madrid, Spain
| | - Ana Belén Sanz
- Nephrology Laboratory, IIS-Fundación Jiménez Díaz, Autonomous University of Madrid and REDINREN, Madrid, Spain
| | - Julián Segura
- Cardiorenal Translational Laboratory, Institute of Research Imas12, Hospital Universitario 12 de Octubre, Madrid, Spain
- Servicio de Nefrología, Hospital Universitario 12 de Octubre, Madrid, Spain
| | - María Fernández-Velasco
- IdiPAZ Institute for Health Research/Centro de Investigación Biomédica en Red de Enfermedades Cardiovasculares, CIBER-CV, Madrid, Spain
| | - Fernando Liaño
- Instituto Ramón y Cajal de Investigación Sanitaria (IRyCis), Madrid, Spain
| | - Luis M Ruilope
- Cardiorenal Translational Laboratory, Institute of Research Imas12, Hospital Universitario 12 de Octubre, Madrid, Spain
- CIBER-CV, Hospital Universitario 12 de Octubre, Madrid, Spain
- School of Doctoral Studies and Research, European University of Madrid, Madrid, Spain
| | - Gema Ruiz-Hurtado
- Cardiorenal Translational Laboratory, Institute of Research Imas12, Hospital Universitario 12 de Octubre, Madrid, Spain
- CIBER-CV, Hospital Universitario 12 de Octubre, Madrid, Spain
- Departamento de Fisiología, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
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3
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Sabatino L. Nrf2-Mediated Antioxidant Defense and Thyroid Hormone Signaling: A Focus on Cardioprotective Effects. Antioxidants (Basel) 2023; 12:1177. [PMID: 37371907 DOI: 10.3390/antiox12061177] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Revised: 05/24/2023] [Accepted: 05/28/2023] [Indexed: 06/29/2023] Open
Abstract
Thyroid hormones (TH) perform a plethora of actions in numerous tissues and induce an overall increase in metabolism, with an augmentation in energy demand and oxygen expenditure. Oxidants are required for normal thyroid-cell proliferation, as well as for the synthesis of the main hormones secreted by the thyroid gland, triiodothyronine (T3) and thyroxine (T4). However, an uncontrolled excess of oxidants can cause oxidative stress, a major trigger in the pathogenesis of a broad spectrum of diseases, including inflammation and cancer. In particular, oxidative stress is implicated in both hypo- and hyper-thyroid diseases. Furthermore, it is important for the TH system to rely on efficient antioxidant defense, to maintain balance, despite sustained tissue exposure to oxidants. One of the main endogenous antioxidant responses is the pathway centered on the nuclear factor erythroid 2-related factor (Nrf2). The aim of the present review is to explore the multiple links between Nrf2-related pathways and various TH-associated conditions. The main aspect of TH signaling is described and the role of Nrf2 in oxidant-antioxidant homeostasis in the TH system is evaluated. Next, the antioxidant function of Nrf2 associated with oxidative stress induced by TH pathological excess is discussed and, subsequently, particular attention is given to the cardioprotective role of TH, which also acts through the mediation of Nrf2. In conclusion, the interaction between Nrf2 and most common natural antioxidant agents in altered states of TH is briefly evaluated.
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Affiliation(s)
- Laura Sabatino
- Institute of Clinical Physiology, National Research Council, Via Moruzzi 1, 56124 Pisa, Italy
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4
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Defining the molecular underpinnings controlling cardiomyocyte proliferation. Clin Sci (Lond) 2022; 136:911-934. [PMID: 35723259 DOI: 10.1042/cs20211180] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Revised: 05/27/2022] [Accepted: 05/31/2022] [Indexed: 12/11/2022]
Abstract
Shortly after birth, mammalian cardiomyocytes (CM) exit the cell cycle and cease to proliferate. The inability of adult CM to replicate renders the heart particularly vulnerable to injury. Restoration of CM proliferation would be an attractive clinical target for regenerative therapies that can preserve contractile function and thus prevent the development of heart failure. Our review focuses on recent progress in understanding the tight regulation of signaling pathways and their downstream molecular mechanisms that underly the inability of CM to proliferate in vivo. In this review, we describe the temporal expression of cell cycle activators e.g., cyclin/Cdk complexes and their inhibitors including p16, p21, p27 and members of the retinoblastoma gene family during gestation and postnatal life. The differential impact of members of the E2f transcription factor family and microRNAs on the regulation of positive and negative cell cycle factors is discussed. This review also highlights seminal studies that identified the coordination of signaling mechanisms that can potently activate CM cell cycle re-entry including the Wnt/Ctnnb1, Hippo, Pi3K-Akt and Nrg1-Erbb2/4 pathways. We also present an up-to-date account of landmark studies analyzing the effect of various genes such as Argin, Dystrophin, Fstl1, Meis1, Pitx2 and Pkm2 that are responsible for either inhibition or activation of CM cell division. All these reports describe bona fide therapeutically targets that could guide future clinical studies toward cardiac repair.
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5
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Cervantes DO, Pizzo E, Ketkar H, Parambath SP, Tang S, Cianflone E, Cannata A, Vinukonda G, Jain S, Jacobson JT, Rota M. Scn1b expression in the adult mouse heart modulates Na + influx in myocytes and reveals a mechanistic link between Na + entry and diastolic function. Am J Physiol Heart Circ Physiol 2022; 322:H975-H993. [PMID: 35394857 PMCID: PMC9076421 DOI: 10.1152/ajpheart.00465.2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 03/09/2022] [Accepted: 03/23/2022] [Indexed: 11/22/2022]
Abstract
Voltage-gated sodium channels (VGSCs) are macromolecular assemblies composed of a number of proteins regulating channel conductance and properties. VGSCs generate Na+ current (INa) in myocytes and play fundamental roles in excitability and impulse conduction in the heart. Moreover, VGSCs condition mechanical properties of the myocardium, a process that appears to involve the late component of INa. Variants in the gene SCN1B, encoding the VGSC β1- and β1B-subunits, result in inherited neurological disorders and cardiac arrhythmias. But the precise contributions of β1/β1B-subunits and VGSC integrity to the overall function of the adult heart remain to be clarified. For this purpose, adult mice with cardiac-restricted, inducible deletion of Scn1b (conditional knockout, cKO) were studied. Myocytes from cKO mice had increased densities of fast (+20%)- and slow (+140%)-inactivating components of INa, with respect to control cells. By echocardiography and invasive hemodynamics, systolic function was preserved in cKO mice, but diastolic properties and ventricular compliance were compromised, with respect to control animals. Importantly, inhibition of late INa with GS967 normalized left ventricular filling pattern and isovolumic relaxation time in cKO mice. At the cellular level, cKO myocytes presented delayed kinetics of Ca2+ transients and cell mechanics, defects that were corrected by inhibition of INa. Collectively, these results document that VGSC β1/β1B-subunits modulate electrical and mechanical function of the heart by regulating, at least in part, Na+ influx in cardiomyocytes.NEW & NOTEWORTHY We have investigated the consequences of deletion of Scn1b, the gene encoding voltage-gated sodium channel β1-subunits, on myocyte and cardiac function. Our findings support the notion that Scn1b expression controls properties of Na+ influx and Ca2+ cycling in cardiomyocytes affecting the modality of cell contraction and relaxation. These effects at the cellular level condition electrical recovery and diastolic function in vivo, substantiating the multifunctional role of β1-subunits in the physiology of the heart.
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Affiliation(s)
| | - Emanuele Pizzo
- Department of Physiology, New York Medical College, Valhalla, New York
| | - Harshada Ketkar
- Department of Pathology, Microbiology and Immunology, New York Medical College, Valhalla, New York
| | - Sreema P Parambath
- Department of Pathology, Microbiology and Immunology, New York Medical College, Valhalla, New York
| | - Samantha Tang
- Department of Pathology, Microbiology and Immunology, New York Medical College, Valhalla, New York
| | - Eleonora Cianflone
- Department of Physiology, New York Medical College, Valhalla, New York
- Molecular and Cellular Cardiology, Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy
| | - Antonio Cannata
- School of Cardiovascular Medicine and Sciences, King's College London British Heart Foundation Centre of Excellence, London, United Kingdom
| | | | - Sudhir Jain
- Department of Pathology, Microbiology and Immunology, New York Medical College, Valhalla, New York
| | - Jason T Jacobson
- Department of Physiology, New York Medical College, Valhalla, New York
- Department of Cardiology, Westchester Medical Center, Valhalla, New York
| | - Marcello Rota
- Department of Physiology, New York Medical College, Valhalla, New York
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Pizzo E, Berrettoni S, Kaul R, Cervantes DO, Di Stefano V, Jain S, Jacobson JT, Rota M. Heart Rate Variability Reveals Altered Autonomic Regulation in Response to Myocardial Infarction in Experimental Animals. Front Cardiovasc Med 2022; 9:843144. [PMID: 35586660 PMCID: PMC9108187 DOI: 10.3389/fcvm.2022.843144] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Accepted: 04/04/2022] [Indexed: 12/24/2022] Open
Abstract
The analysis of beating rate provides information on the modulatory action of the autonomic nervous system on the heart, which mediates adjustments of cardiac function to meet hemodynamic requirements. In patients with myocardial infarction, alterations of heart rate variability (HRV) have been correlated to the occurrence of arrhythmic events and all-cause mortality. In the current study, we tested whether experimental rodent models of myocardial infarction recapitulate dynamics of heart rate variability observed in humans, and constitute valid platforms for understanding mechanisms linking autonomic function to the development and manifestation of cardiovascular conditions. For this purpose, HRV was evaluated in two engineered mouse lines using electrocardiograms collected in the conscious, restrained state, using a tunnel device. Measurements were obtained in naïve mice and animals at 3–∼28 days following myocardial infarction, induced by permanent coronary artery ligation. Two mouse lines with inbred and hybrid genetic background and, respectively, homozygous (Homo) and heterozygous (Het) for the MerCreMer transgene, were employed. In the naïve state, Het female and male mice presented prolonged RR interval duration (∼9%) and a ∼4-fold increased short- and long-term RR interval variability, with respect to sex-matched Homo mice. These differences were abrogated by pharmacological interventions inhibiting the sympathetic and parasympathetic axes. At 3–∼14 days after myocardial infarction, RR interval duration increased in Homo mice, but was not affected in Het animals. In contrast, Homo mice had minor modifications in HRV parameters, whereas substantial (> 50%) reduction of short- and long-term RR interval variation occurred in Het mice. Interestingly, ex vivo studies in isolated organs documented that intrinsic RR interval duration increased in infarcted vs. non-infarcted Homo and Het hearts, whereas RR interval variation was not affected. In conclusion, our study documents that, as observed in humans, myocardial infarction in rodents is associated with alterations in heart rhythm dynamics consistent with sympathoexcitation and parasympathetic withdrawal. Moreover, we report that mouse strain is an important variable when evaluating autonomic function via the analysis of HRV.
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Affiliation(s)
- Emanuele Pizzo
- Department of Physiology, New York Medical College, Valhalla, NY, United States
| | - Silvia Berrettoni
- Department of Physiology, New York Medical College, Valhalla, NY, United States
| | - Ridhima Kaul
- Department of Physiology, New York Medical College, Valhalla, NY, United States
| | - Daniel O. Cervantes
- Department of Physiology, New York Medical College, Valhalla, NY, United States
| | - Valeria Di Stefano
- Department of Physiology, New York Medical College, Valhalla, NY, United States
| | - Sudhir Jain
- Department of Pathology, Microbiology and Immunology, New York Medical College, Valhalla, NY, United States
| | - Jason T. Jacobson
- Department of Physiology, New York Medical College, Valhalla, NY, United States
- Department of Cardiology, Westchester Medical Center, Valhalla, NY, United States
| | - Marcello Rota
- Department of Physiology, New York Medical College, Valhalla, NY, United States
- *Correspondence: Marcello Rota,
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7
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Hormetic-like dose-response induced by alternagin-C, a protein isolated from urutu snake (Rhinocerophis alternatus) venom, in fish (Hoplias malabaricus) cardiac contractility. Toxicon 2022; 205:67-70. [PMID: 34838810 DOI: 10.1016/j.toxicon.2021.11.123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 11/19/2021] [Accepted: 11/22/2021] [Indexed: 11/21/2022]
Abstract
The aim of this study was to evaluate the effects of different doses of alternagin-C, a disintegrin-like protein from Rhinocerophis alternatus venom, on myocardial contractility of the freshwater fish Hoplias malabaricus, an alternative model to contractile function studies. Alternagin-C treatment exhibited a hormetic-like dose-response curve with a strong positive inotropism and enhanced cardiac pumping capacity at low dose, whereas a modest inotropism and a left shift in the force-frequency relationship was registered at high dose.
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Zhang N, Ye F, Zhou Y, Zhu W, Xie C, Zheng H, Chen H, Chen J, Xie X. Cardiac ankyrin repeat protein contributes to dilated cardiomyopathy and heart failure. FASEB J 2021; 35:e21488. [PMID: 33734499 DOI: 10.1096/fj.201902802rr] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2019] [Revised: 02/13/2021] [Accepted: 02/15/2021] [Indexed: 11/11/2022]
Abstract
Cardiac ankyrin repeat protein (CARP) is a cardiac-specific stress-response protein which exerts diverse effects to modulate cardiac remodeling in response to pathological stimuli. We examined the role of CARP in postnatal cardiac development and function under basal conditions in mice. Transgenic mice that selectively overexpressed CARP in heart (CARP Tg) exhibited dilated cardiac chambers, impaired heart function, and cardiac fibrosis as assessed by echocardiography and histological staining. Furthermore, the mice had a shorter lifespan and reduced survival rate in response to ischemic acute myocardial infarction. Immunofluorescence demonstrated the overexpressed CARP protein was predominantly accumulated in the nuclei of cardiomyocytes. Microarray analysis revealed that the nuclear localization of CARP was associated with the suppression of calcium-handling proteins. In vitro experiments revealed that CARP overexpression resulted in decreased cell contraction and calcium transient. In post-mortem cardiac specimens from patients with dilated cardiomyopathy and end-stage heart failure, CARP was significantly increased. Taken together, our data identified CARP as a crucial contributor in dilated cardiomyopathy and heart failure which was associated with its regulation of calcium-handling proteins.
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Affiliation(s)
- Na Zhang
- Department of Cardiology, Cardiovascular Key Lab of Zhejiang Province, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, People's Republic of China.,School of Medicine, Hangzhou Normal University, Hangzhou, People's Republic of China
| | - Feiming Ye
- Department of Cardiology, Cardiovascular Key Lab of Zhejiang Province, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, People's Republic of China
| | - Yu Zhou
- Department of Cardiology, Cardiovascular Key Lab of Zhejiang Province, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, People's Republic of China
| | - Wei Zhu
- Department of Cardiology, Cardiovascular Key Lab of Zhejiang Province, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, People's Republic of China
| | - Cuiping Xie
- Department of Cardiology, Cardiovascular Key Lab of Zhejiang Province, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, People's Republic of China
| | - Haiqiong Zheng
- Department of Cardiology, Cardiovascular Key Lab of Zhejiang Province, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, People's Republic of China
| | - Han Chen
- Department of Cardiology, Cardiovascular Key Lab of Zhejiang Province, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, People's Republic of China
| | - Jinghai Chen
- Department of Cardiology, Cardiovascular Key Lab of Zhejiang Province, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, People's Republic of China.,Institute of Translational Medicine, Zhejiang University, Hangzhou, People's Republic of China
| | - Xiaojie Xie
- Department of Cardiology, Cardiovascular Key Lab of Zhejiang Province, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, People's Republic of China
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Zeng B, Liu L, Liao X, Zhang C. Cardiomyocyte protective effects of thyroid hormone during hypoxia/reoxygenation injury through activating of IGF-1-mediated PI3K/Akt signalling. J Cell Mol Med 2021; 25:3205-3215. [PMID: 33724692 PMCID: PMC8034470 DOI: 10.1111/jcmm.16389] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 01/08/2021] [Accepted: 02/04/2021] [Indexed: 12/17/2022] Open
Abstract
Ischaemia/reperfusion (I/R) injury is a common clinical condition that results in apoptosis and oxidative stress injury. Thyroid hormone was previously reported to elicit cardiac myocyte hypertrophy and promote cardiac function after cardiac injury. We used an in vivo mouse model of I/R injury and in vitro primary cardiomyocyte culture assays to investigate the effects of thyroid hormone on cardiomyocytes during hypoxia/reoxygenation (H/R) injury. The results showed that T3 pretreatment in vivo significantly improved left ventricular function after I/R injury. In vitro, T3 pretreatment decreased cell apoptosis rate, inhibited caspase‐3 activity and decreased the Bax/Bcl‐2 ration induced by H/R injury. T3 pretreatment significantly attenuated the loss of mitochondrial membrane potential. Furthermore, it was observed that T3 diminished the expression of NCX1 protein and decreased SERCA2a protein expression in H/R‐induced cardiomyocytes, and T3 prevented intracellular Ca2+ increase during H/R injury. Also, T3 increased the expression of IGF‐1, and PI3K/Akt signalling in cardiomyocytes under H/R‐induced injury, and that the protective effect of T3 against H/R‐induced injury was blocked by the PI3K inhibitor LY294002. IGF‐1 receptor (IGF‐1R) inhibitor GSK1904529A significantly inhibited the expression of IGF‐1R and PI3K/Akt signalling. In summary, T3 pretreatment protects cardiomyocytes against H/R‐induced injury by activating the IGF‐1‐mediated PI3K/Akt signalling pathway.
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Affiliation(s)
- Bin Zeng
- Hubei Key Laboratory of Cardiology, Department of Cardiology, Cardiovascular Research Institute, Renmin Hospital of Wuhan University, Wuhan University, Wuhan, China
| | - Lei Liu
- Department of Cardiology, Hubei No. 3 People's Hospital of Jianghan University, Wuhan, China
| | - Xiaoting Liao
- Hubei Key Laboratory of Cardiology, Department of Cardiology, Cardiovascular Research Institute, Renmin Hospital of Wuhan University, Wuhan University, Wuhan, China
| | - Caixia Zhang
- Hubei Key Laboratory of Cardiology, Department of Cardiology, Cardiovascular Research Institute, Renmin Hospital of Wuhan University, Wuhan University, Wuhan, China
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10
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Miao K, Zhou L, Ba H, Li C, Gu H, Yin B, Wang J, Yang XP, Li Z, Wang DW. Transmembrane tumor necrosis factor alpha attenuates pressure-overload cardiac hypertrophy via tumor necrosis factor receptor 2. PLoS Biol 2020; 18:e3000967. [PMID: 33270628 PMCID: PMC7714153 DOI: 10.1371/journal.pbio.3000967] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2019] [Accepted: 10/23/2020] [Indexed: 12/20/2022] Open
Abstract
Tumor necrosis factor-alpha (TNF-α) plays an important pathogenic role in cardiac hypertrophy and heart failure (HF); however, anti-TNF is paradoxically negative in clinical trials and even worsens HF, indicating a possible protective role of TNF-α in HF. TNF-α exists in transmembrane (tmTNF-α) and soluble (sTNF-α) forms. Herein, we found that TNF receptor 1 (TNFR1) knockout (KO) or knockdown (KD) by short hairpin RNA or small interfering RNA (siRNA) significantly alleviated cardiac hypertrophy, heart dysfunction, fibrosis, and inflammation with increased tmTNF-α expression, whereas TNFR2 KO or KD exacerbated the pathological phenomena with increased sTNF-α secretion in transverse aortic constriction (TAC)- and isoproterenol (ISO)-induced cardiac hypertrophy in vivo and in vitro, respectively, indicating the beneficial effects of TNFR2 associated with tmTNF-α. Suppressing TNF-α converting enzyme by TNF-α Protease Inhibitor-1 (TAPI-1) to increase endogenous tmTNF-α expression significantly alleviated TAC-induced cardiac hypertrophy. Importantly, direct addition of exogenous tmTNF-α into cardiomyocytes in vitro significantly reduced ISO-induced cardiac hypertrophy and transcription of the pro-inflammatory cytokines and induced proliferation. The beneficial effects of tmTNF-α were completely blocked by TNFR2 KD in H9C2 cells and TNFR2 KO in primary myocardial cells. Furthermore, we demonstrated that tmTNF-α displayed antihypertrophic and anti-inflammatory effects by activating the AKT pathway and inhibiting the nuclear factor (NF)-κB pathway via TNFR2. Our data suggest that tmTNF-α exerts cardioprotective effects via TNFR2. Specific targeting of tmTNF-α processing, rather than anti-TNF therapy, may be more useful for the treatment of hypertrophy and HF. In contrast to detrimental effects of soluble tumor necrosis factor-alpha (TNF-α) via TNFR1, this study shows that transmembrane TNF-α protects the heart by suppressing pressure overload-induced cardiac hypertrophy and inflammation via TNFR2. Targeting tmTNF-α processing may be more useful than TNF-antagonist for treatment of hypertrophy and heart failure.
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MESH Headings
- Animals
- Apoptosis/drug effects
- Cardiomegaly/metabolism
- Cardiomegaly/physiopathology
- Male
- Mice
- Mice, Inbred BALB C
- Mice, Knockout
- Myocytes, Cardiac/metabolism
- NF-kappa B/metabolism
- Receptors, Tumor Necrosis Factor, Type I/genetics
- Receptors, Tumor Necrosis Factor, Type I/metabolism
- Receptors, Tumor Necrosis Factor, Type II/genetics
- Receptors, Tumor Necrosis Factor, Type II/metabolism
- Receptors, Tumor Necrosis Factor, Type II/physiology
- Signal Transduction/drug effects
- Tumor Necrosis Factor-alpha/metabolism
- Tumor Necrosis Factor-alpha/physiology
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Affiliation(s)
- Kun Miao
- Division of Cardiology, Department of Internal Medicine and Department of Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiologic Disorders, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Ling Zhou
- Division of Cardiology, Department of Internal Medicine and Department of Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiologic Disorders, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Hongping Ba
- Department of Immunology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Chenxi Li
- Department of Immunology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Haiyan Gu
- Department of Immunology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Bingjiao Yin
- Department of Immunology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Jing Wang
- Department of Immunology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Xiang-ping Yang
- Department of Immunology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Zhuoya Li
- Department of Immunology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
- * E-mail: (ZL); (DWW)
| | - Dao Wen Wang
- Division of Cardiology, Department of Internal Medicine and Department of Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiologic Disorders, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
- * E-mail: (ZL); (DWW)
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11
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Stewart RM, Rodriguez EC, King MC. Ablation of SUN2-containing LINC complexes drives cardiac hypertrophy without interstitial fibrosis. Mol Biol Cell 2019; 30:1664-1675. [PMID: 31091167 PMCID: PMC6727752 DOI: 10.1091/mbc.e18-07-0438] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The cardiomyocyte cytoskeleton, including the sarcomeric contractile apparatus, forms a cohesive network with cellular adhesions at the plasma membrane and nuclear--cytoskeletal linkages (LINC complexes) at the nuclear envelope. Human cardiomyopathies are genetically linked to the LINC complex and A-type lamins, but a full understanding of disease etiology in these patients is lacking. Here we show that SUN2-null mice display cardiac hypertrophy coincident with enhanced AKT/MAPK signaling, as has been described previously for mice lacking A-type lamins. Surprisingly, in contrast to lamin A/C-null mice, SUN2-null mice fail to show coincident fibrosis or upregulation of pathological hypertrophy markers. Thus, cardiac hypertrophy is uncoupled from profibrotic signaling in this mouse model, which we tie to a requirement for the LINC complex in productive TGFβ signaling. In the absence of SUN2, we detect elevated levels of the integral inner nuclear membrane protein MAN1, an established negative regulator of TGFβ signaling, at the nuclear envelope. We suggest that A-type lamins and SUN2 play antagonistic roles in the modulation of profibrotic signaling through opposite effects on MAN1 levels at the nuclear lamina, suggesting a new perspective on disease etiology.
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Affiliation(s)
- Rachel M Stewart
- Department of Cell Biology, Yale School of Medicine, New Haven, CT 06520-8002
| | - Elisa C Rodriguez
- Department of Cell Biology, Yale School of Medicine, New Haven, CT 06520-8002
| | - Megan C King
- Department of Cell Biology, Yale School of Medicine, New Haven, CT 06520-8002
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12
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Zeng B, Liu L, Liao X, Zhang C, Ruan H. Thyroid hormone protects cardiomyocytes from H 2O 2-induced oxidative stress via the PI3K-AKT signaling pathway. Exp Cell Res 2019; 380:205-215. [PMID: 31059699 DOI: 10.1016/j.yexcr.2019.05.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 04/30/2019] [Accepted: 05/02/2019] [Indexed: 01/14/2023]
Abstract
Oxidative stress plays an important role in the progression of cardiac diseases, including acute myocardial infarction, ischemia/reperfusion (I/R) injury and heart failure. Growing evidence indicates that thyroid hormone has protective properties against cardiovascular diseases. However, little is known about its effect on oxidative stress in cardiomyocytes or the underlying mechanisms. This study showed that T3 pretreatment in vivo significantly reduced cardiac dysfunction by increasing the left ventricular ejection function and ameliorating the pathological changes induced by I/R-induced injury. In an in vitro experiment, T3 inhibited apoptosis in H2O2-treated cardiomyocytes, as evidenced by the decreased expression of Bax, cleaved caspase 3 and 9, and increased expression of Bcl-2. In addition, oxidative stress observed in hearts of mice with I/R injury was significantly alleviated by T3 pretreatment, intracellular ROS and mitochondrial ROS overproduction were effectively inhibited, and similar results were also detected in H2O2-treated cardiomyocytes in vitro. T3 significantly increased antioxidant protein (Nrf2 and HO-1) expression levels, and inhibited NOX2 and NOX4 protein expression levels in H2O2-treated cardiomyocytes. Moreover, T3 preserved mitochondrial functions upon H2O2-induced oxidative stress by increasing mitochondrial membrane potential and promoting the expression of mitochondrial biogenesis genes. Notably, the PI3K/AKT signaling was significantly activated by T3 pretreatment in H2O2-induced cardiomyocytes. Together, these findings revealed that T3 could be served as potential therapeutic target for protection against cardiac oxidative stress injury through its antioxidant and anti-apoptosis effects, which are mediated by the activation of the PI3K/AKT signaling pathway.
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Affiliation(s)
- Bin Zeng
- Department of Cardiology, Renmin Hospital of Wuhan University, Cardiovascular Research Institute, Wuhan University, Hubei Key Laboratory of Cardiology, Wuhan, Hubei, PR China.
| | - Lei Liu
- Department of Cardiology, Renmin Hospital of Wuhan University, Cardiovascular Research Institute, Wuhan University, Hubei Key Laboratory of Cardiology, Wuhan, Hubei, PR China
| | - Xiaoting Liao
- Department of Cardiology, Renmin Hospital of Wuhan University, Cardiovascular Research Institute, Wuhan University, Hubei Key Laboratory of Cardiology, Wuhan, Hubei, PR China
| | - Caixia Zhang
- Department of Cardiology, Renmin Hospital of Wuhan University, Cardiovascular Research Institute, Wuhan University, Hubei Key Laboratory of Cardiology, Wuhan, Hubei, PR China
| | - Huaiyu Ruan
- Department of Cardiology, Renmin Hospital of Wuhan University, Cardiovascular Research Institute, Wuhan University, Hubei Key Laboratory of Cardiology, Wuhan, Hubei, PR China
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13
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Wang B, Zhang A, Wang H, Klein JD, Tan L, Wang ZM, Du J, Naqvi N, Liu BC, Wang XH. miR-26a Limits Muscle Wasting and Cardiac Fibrosis through Exosome-Mediated microRNA Transfer in Chronic Kidney Disease. Am J Cancer Res 2019; 9:1864-1877. [PMID: 31037144 PMCID: PMC6485283 DOI: 10.7150/thno.29579] [Citation(s) in RCA: 100] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Accepted: 01/19/2019] [Indexed: 12/21/2022] Open
Abstract
Uremic cardiomyopathy and muscle atrophy are associated with insulin resistance and contribute to chronic kidney disease (CKD)-induced morbidity and mortality. We hypothesized that restoration of miR-26a levels would enhance exosome-mediated microRNA transfer to improve muscle wasting and cardiomyopathy that occur in CKD. Methods: Using next generation sequencing and qPCR, we found that CKD mice had a decreased level of miR-26a in heart and skeletal muscle. We engineered an exosome vector that contained Lamp2b, an exosomal membrane protein gene fused with a muscle-specific surface peptide that targets muscle delivery. We transfected this vector into muscle satellite cells and then transduced these cells with adenovirus that expresses miR-26a to produce exosomes encapsulated miR-26a (Exo/miR-26a). Exo/miR-26a was injected once per week for 8 weeks into the tibialis anterior (TA) muscle of 5/6 nephrectomized CKD mice. Results: Treatment with Exo/miR-26a resulted in increased expression of miR-26a in skeletal muscle and heart. Overexpression of miR-26a increased the skeletal muscle cross-sectional area, decreased the upregulation of FBXO32/atrogin-1 and TRIM63/MuRF1 and depressed cardiac fibrosis lesions. In the hearts of CKD mice, FoxO1 was activated, and connective tissue growth factor, fibronectin and collagen type I alpha 1 were increased. These responses were blunted by injection of Exo/miR-26a. Echocardiograms showed that cardiac function was improved in CKD mice treated with Exo/miR-26a. Conclusion: Overexpression of miR-26a in muscle prevented CKD-induced muscle wasting and attenuated cardiomyopathy via exosome-mediated miR-26a transfer. These results suggest possible therapeutic strategies for using exosome delivery of miR-26a to treat complications of CKD.
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14
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Marotta P, Cianflone E, Aquila I, Vicinanza C, Scalise M, Marino F, Mancuso T, Torella M, Indolfi C, Torella D. Combining cell and gene therapy to advance cardiac regeneration. Expert Opin Biol Ther 2018; 18:409-423. [PMID: 29347847 DOI: 10.1080/14712598.2018.1430762] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
INTRODUCTION The characterization of multipotent endogenous cardiac stem cells (eCSCs) and the breakthroughs of somatic cell reprogramming to boost cardiomyocyte replacement have fostered the prospect of achieving functional heart repair/regeneration. AREAS COVERED Allogeneic CSC therapy through its paracrine stimulation of the endogenous resident reparative/regenerative process produces functional meaningful myocardial regeneration in pre-clinical porcine myocardial infarction models and is currently tested in the first-in-man human trial. The in vivo test of somatic reprogramming and cardioregenerative non-coding RNAs revived the interest in gene therapy for myocardial regeneration. The latter, together with the advent of genome editing, has prompted most recent efforts to produce genetically-modified allogeneic CSCs that secrete cardioregenerative factors to optimize effective myocardial repair. EXPERT OPINION The current war against heart failure epidemics in western countries seeks to find effective treatments to set back the failing hearts prolonging human lifespan. Off-the-shelf allogeneic-genetically-modified CSCs producing regenerative agents are a novel and evolving therapy set to be affordable, safe, effective and available at all times for myocardial regeneration to either prevent or treat heart failure.
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Affiliation(s)
- Pina Marotta
- a Molecular and Cellular Cardiology, Department of Medical and Surgical Sciences , Magna Graecia University , Catanzaro , Italy
| | - Eleonora Cianflone
- a Molecular and Cellular Cardiology, Department of Medical and Surgical Sciences , Magna Graecia University , Catanzaro , Italy
| | - Iolanda Aquila
- a Molecular and Cellular Cardiology, Department of Medical and Surgical Sciences , Magna Graecia University , Catanzaro , Italy
| | - Carla Vicinanza
- a Molecular and Cellular Cardiology, Department of Medical and Surgical Sciences , Magna Graecia University , Catanzaro , Italy
| | - Mariangela Scalise
- a Molecular and Cellular Cardiology, Department of Medical and Surgical Sciences , Magna Graecia University , Catanzaro , Italy
| | - Fabiola Marino
- a Molecular and Cellular Cardiology, Department of Medical and Surgical Sciences , Magna Graecia University , Catanzaro , Italy
| | - Teresa Mancuso
- a Molecular and Cellular Cardiology, Department of Medical and Surgical Sciences , Magna Graecia University , Catanzaro , Italy
| | - Michele Torella
- b Department of Cardiothoracic Sciences , University of Campania "L. Vanvitelli" , Naples , Italy
| | - Ciro Indolfi
- a Molecular and Cellular Cardiology, Department of Medical and Surgical Sciences , Magna Graecia University , Catanzaro , Italy
| | - Daniele Torella
- a Molecular and Cellular Cardiology, Department of Medical and Surgical Sciences , Magna Graecia University , Catanzaro , Italy
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15
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Roy R, Krenz M. Heterozygous deletion of AKT1 rescues cardiac contractility, but not hypertrophy, in a mouse model of Noonan Syndrome with Multiple Lentigines. J Mol Cell Cardiol 2017; 112:83-90. [PMID: 28911943 DOI: 10.1016/j.yjmcc.2017.09.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Revised: 08/24/2017] [Accepted: 09/10/2017] [Indexed: 10/18/2022]
Abstract
Noonan Syndrome with Multiple Lentigines (NSML) is associated with congenital heart disease in form of pulmonary valve stenosis and hypertrophic cardiomyopathy (HCM). Genetically, NSML is primarily caused by mutations in the non-receptor protein tyrosine phosphatase SHP2. Importantly, certain SHP2 mutations such as Q510E can cause a particularly severe form of HCM with heart failure in infancy. Due to lack of insight into the underlying pathomechanisms, an effective custom-tailored therapy to prevent heart failure in these patients has not yet been found. SHP2 regulates numerous signaling cascades governing cell growth, differentiation, and survival. Experimental models have shown that NSML mutations in SHP2 cause dysregulation of downstream signaling, in particular involving the protein kinase AKT. AKT, and especially the isoform AKT1, has been shown to be a major regulator of cardiac hypertrophy. We therefore hypothesized that hyperactivation of AKT1 is required for the development of Q510E-SHP2-induced HCM. We previously generated a transgenic mouse model of NSML-associated HCM induced by Q510E-SHP2 expression in cardiomyocytes starting before birth. Mice display neonatal-onset HCM with initially preserved contractile function followed by functional decline around 2months of age. As a proof-of-principle study, our current goal was to establish to which extent a genetic reduction in AKT1 rescues the Q510E-SHP2-induced cardiac phenotype in vivo. AKT1 deletion mice were crossed with Q510E-SHP2 transgenic mice and the resulting compound mutant offspring analyzed. Homozygous deletion of AKT1 greatly reduced viability in our NSML mouse model, whereas heterozygous deletion of AKT1 in combination with Q510E-SHP2 expression was well tolerated. Despite normalization of pro-hypertrophic signaling downstream of AKT, heterozygous deletion of AKT1 did not ameliorate cardiac hypertrophy induced by Q510E-SHP2. However, the functional decline caused by Q510E-SHP2 expression was effectively prevented by reducing AKT1 protein. This demonstrates that AKT1 plays an important role in the underlying pathomechanism. Furthermore, the functional rescue was associated with an increase in the capillary-to-cardiomyocyte ratio and normalization of capillary density per tissue area in the compound mutant offspring. We therefore speculate that limited oxygen supply to the hypertrophied cardiomyocytes may contribute to the functional decline observed in our mouse model of NSML-associated HCM.
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Affiliation(s)
- Rajika Roy
- Dalton Cardiovascular Research Center, Department of Medical Pharmacology & Physiology, School of Medicine, University of Missouri, 134 Research Park Dr, Columbia, MO 65211, United States
| | - Maike Krenz
- Dalton Cardiovascular Research Center, Department of Medical Pharmacology & Physiology, School of Medicine, University of Missouri, 134 Research Park Dr, Columbia, MO 65211, United States.
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16
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Booth SA, Charchar FJ. Cardiac telomere length in heart development, function, and disease. Physiol Genomics 2017; 49:368-384. [DOI: 10.1152/physiolgenomics.00024.2017] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Telomeres are repetitive nucleoprotein structures at chromosome ends, and a decrease in the number of these repeats, known as a reduction in telomere length (TL), triggers cellular senescence and apoptosis. Heart disease, the worldwide leading cause of death, often results from the loss of cardiac cells, which could be explained by decreases in TL. Due to the cell-specific regulation of TL, this review focuses on studies that have measured telomeres in heart cells and critically assesses the relationship between cardiac TL and heart function. There are several lines of evidence that have identified rapid changes in cardiac TL during the onset and progression of heart disease as well as at critical stages of development. There are also many factors, such as the loss of telomeric proteins, oxidative stress, and hypoxia, that decrease cardiac TL and heart function. In contrast, antioxidants, calorie restriction, and exercise can prevent both cardiac telomere attrition and the progression of heart disease. TL in the heart is also indicative of proliferative potential and could facilitate the identification of cells suitable for cardiac rejuvenation. Although these findings highlight the involvement of TL in heart function, there are important questions regarding the validity of animal models, as well as several confounding factors, that need to be considered when interpreting results and planning future research. With these in mind, elucidating the telomeric mechanisms involved in heart development and the transition to disease holds promise to prevent cardiac dysfunction and potentiate regeneration after injury.
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Affiliation(s)
- S. A. Booth
- Faculty of Science and Technology, School of Applied and Biomedical Sciences, Federation University Australia, Balllarat, Australia
| | - F. J. Charchar
- Faculty of Science and Technology, School of Applied and Biomedical Sciences, Federation University Australia, Balllarat, Australia
- Department of Physiology, The University of Melbourne, Melbourne, Australia; and
- Department of Cardiovascular Sciences, University of Leicester, Leicester, United Kingdom
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17
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Fan TT, Feng XY, Yang YZ, Gao F, Liu Q. Downregulation of PI3K-γ in a mouse model of sepsis-induced myocardial dysfunction. Cytokine 2017; 96:208-216. [PMID: 28458167 DOI: 10.1016/j.cyto.2017.04.018] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2016] [Revised: 04/17/2017] [Accepted: 04/18/2017] [Indexed: 01/25/2023]
Abstract
A key component during sepsis is the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway, of which the PI3K-γ isoform is a major regulator in many inflammatory responses. However, the role of PI3K-γ in the development of sepsis-induced myocardial dysfunction (SIMD) is unknown. In this study, we established a model of SIMD induced by lipopolysaccharide (LPS), subsequently used the selective inhibitor LY294002 and AS605240 to block the effect of PI3K and PI3K-γ, respectively. Cardiac function was evaluated by echocardiography, hearts were obtained for histological and protein expression examinations. ELISA was used to measure the serum levels of tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6), cardiac troponin I (cTnI) and heart-type fatty acid binding protein (H-FABP). LPS-treated mice showed an increase to cardiac inflammation, myocardial damage and production of TNF-α, IL-6, NF-κB, cTnI and H-FABP. Administration of AS605240 to LPS-treated mice reduced some patho-physiological characteristics of SIMD and reduced TNF-α, IL-6, cTnI and H-FABP production. However, administration of LY294002 did not improve those same conditions. The results showed that PI3K-γ is likely a crucial element in SIMD by regulating the PI3K/Akt pathway, and become a new marker of myocardial injury. Inhibition of PI3K-γ might be a potential therapeutic target in SIMD.
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Affiliation(s)
- Ting-Ting Fan
- Department of Emergency, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, PR China; Department of Emergency, Chengdu First People's Hospital, Sichuan 610016, PR China
| | - Xuan-Yun Feng
- Department of Emergency, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, PR China
| | - Yuan-Zheng Yang
- Department of Critical Care Medicine, The Affiliated Hospital of Hainan Medical College, Hainan 571101, PR China
| | - Feng Gao
- Department of Emergency, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, PR China
| | - Qiong Liu
- Department of Emergency, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, PR China.
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18
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Hu W, Xu T, Wu P, Pan D, Chen J, Chen J, Zhang B, Zhu H, Li D. Luteolin improves cardiac dysfunction in heart failure rats by regulating sarcoplasmic reticulum Ca 2+-ATPase 2a. Sci Rep 2017; 7:41017. [PMID: 28112209 PMCID: PMC5253630 DOI: 10.1038/srep41017] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Accepted: 12/15/2016] [Indexed: 12/24/2022] Open
Abstract
We previously found that luteolin (Lut) appeared to improve the contractility of cardiomyocytes during ischemia/reperfusion in rats. The enhancement was associated with the alteration in sarcoplasmic reticulum Ca2+-ATPase 2a (SERCA2a). This finding prompted us to consider if the mechanism worked in heart failure (HF). We studied the regulation of SERCA2a by Lut in failing cardiomyocytes and intact heart of rats. Improvement of contractility and the mechanisms centered on SERCA2a were studied in isolated cardiomyocytes and intact heart. We found that Lut significantly improved contractility and Ca2+ transients, ameliorated expression, activity and stability of SERCA2a and upregulated expression of small ubiquitin-related modifier (SUMO) 1, which is a newfound SERCA2a regulator. Lut also increased phosphorylation of protein kinase B (Akt), phospholaban (PLB) and sumoylation of SERCA2a, specificity protein 1 (Sp1). Transcriptions of SUMO1 and SERCA2a were concurrently increased. Inhibition of posphatidylinositol 3 kinase/Akt (PI3K/Akt) pathway and SERCA2a activity both markedly abolished Lut-induced benefits in vitro and in vivo. Lut upregulated the expression ratio of Bcl-2/Bax, caspase-3/cleaved-Caspase3. Meanwhile, Lut ameliorated the myocardium fibrosis of HF. These discoveries provide an important potential therapeutic strategy that Lut targeted SERCA2a SUMOylation related to PI3K/Akt-mediated regulations on rescuing the dysfunction of HF.
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Affiliation(s)
- Wenjing Hu
- Institute of Cardiovascular Disease Research, Xuzhou Medical University, Xuzhou, Jiangsu, 221002, China
| | - Tongda Xu
- Department of Cardiology, Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, 221006, China
| | - Pei Wu
- Institute of Cardiovascular Disease Research, Xuzhou Medical University, Xuzhou, Jiangsu, 221002, China
| | - Defeng Pan
- Institute of Cardiovascular Disease Research, Xuzhou Medical University, Xuzhou, Jiangsu, 221002, China
| | - Junhong Chen
- Department of Cardiology, Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, 221006, China
| | - Jing Chen
- Department of Cardiology, Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, 221006, China
| | - Buchun Zhang
- Institute of Cardiovascular Disease Research, Xuzhou Medical University, Xuzhou, Jiangsu, 221002, China
| | - Hong Zhu
- Department of Cardiology, Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, 221006, China
| | - Dongye Li
- Institute of Cardiovascular Disease Research, Xuzhou Medical University, Xuzhou, Jiangsu, 221002, China
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19
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Shuai XX, Meng YD, Lu YX, Su GH, Tao XF, Han J, Xu SD, Luo P. Relaxin-2 improves diastolic function of pressure-overloaded rats via phospholamban by activating Akt. Int J Cardiol 2016; 218:305-311. [PMID: 27240156 DOI: 10.1016/j.ijcard.2016.05.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Revised: 04/18/2016] [Accepted: 05/12/2016] [Indexed: 02/05/2023]
Abstract
BACKGROUND Relaxin is a peptide hormone which has been demonstrated to be safe and has a therapeutic effect on acute heart failure in clinic trials. However, its effect on diastolic function is still unknown. The aims of the study were to determine whether relaxin could improve the diastolic function in pressure-overloaded rat model and to analyze potential mechanisms. METHODS AND RESULTS In the present study, a pressure-overloaded rat model induced by transaortic constriction (TAC) was established. Four weeks after TAC, echocardiography was performed and then all the rat models were randomly divided into 3 groups: models without intramyocardial injection (TAC), with intramyocardial injection of empty adenoviral vector (TAC+GFP) and adenoviral vector overexpression relaxin-2 gene (TAC+RLN2). A sham group was also included. Twelve days after intramyocardial injection, echocardiography and hemodynamics were carried out to evaluate diastolic function in sham, TAC, TAC+GFP and TAC+RLN2 groups. Then hearts were harvested for subsequent examinations. The results indicated that relaxin-2 had ameliorated diastolic function in the pressure-overloaded rats. Compared with the TAC and TAC+GFP groups, the relaxin-2 gene transfer increased phosphorylation of Akt at both the Ser473 and Thr308 sites. Meanwhile, it increased the Ser16 and Thr17- phosphorylation levels of phospholamban (PLB). Furthermore, SERCA2 activity was enhanced in the TAC+RLN2 group more than in the TAC and TAC+GFP groups. CONCLUSIONS These results demonstrated that relaxin-2 gene therapy improved diastolic function in pressure-overloaded rats. The potential mechanism may be that relaxin-2 gene transfer enhances SERCA2 activity in hearts by increasing phospholamban phosphorylation through nuclear-targeted Akt phosphorylation.
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Affiliation(s)
- Xin-Xin Shuai
- Department of Cardiology, Union Hospital, Tongji Medical College of Huazhong University of Science and Technology, Wuhan 430022, China
| | - Yi-di Meng
- Department of Cardiology, Union Hospital, Tongji Medical College of Huazhong University of Science and Technology, Wuhan 430022, China
| | - Yong-Xin Lu
- Department of Cardiology, Union Hospital, Tongji Medical College of Huazhong University of Science and Technology, Wuhan 430022, China.
| | - Guan-Hua Su
- Department of Cardiology, Union Hospital, Tongji Medical College of Huazhong University of Science and Technology, Wuhan 430022, China
| | - Xiao-Fang Tao
- Department of Cardiology, Union Hospital, Tongji Medical College of Huazhong University of Science and Technology, Wuhan 430022, China
| | - Jun Han
- Department of Cardiology, Union Hospital, Tongji Medical College of Huazhong University of Science and Technology, Wuhan 430022, China
| | - Su-Dan Xu
- Department of Cardiology, Union Hospital, Tongji Medical College of Huazhong University of Science and Technology, Wuhan 430022, China
| | - Ping Luo
- Department of Cardiology, Union Hospital, Tongji Medical College of Huazhong University of Science and Technology, Wuhan 430022, China
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20
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Meo M, Meste O, Signore S, Sorrentino A, Cannata A, Zhou Y, Matsuda A, Luciani M, Kannappan R, Goichberg P, Leri A, Anversa P, Rota M. Reduction in Kv Current Enhances the Temporal Dispersion of the Action Potential in Diabetic Myocytes: Insights From a Novel Repolarization Algorithm. J Am Heart Assoc 2016; 5:e003078. [PMID: 26896476 PMCID: PMC4802457 DOI: 10.1161/jaha.115.003078] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2015] [Accepted: 01/02/2016] [Indexed: 02/06/2023]
Abstract
BACKGROUND Diabetes is associated with prolongation of the QT interval of the electrocardiogram and enhanced dispersion of ventricular repolarization, factors that, together with atherosclerosis and myocardial ischemia, may promote the occurrence of electrical disorders. Thus, we tested the possibility that alterations in transmembrane ionic currents reduce the repolarization reserve of myocytes, leading to action potential (AP) prolongation and enhanced beat-to-beat variability of repolarization. METHODS AND RESULTS Diabetes was induced in mice with streptozotocin (STZ), and effects of hyperglycemia on electrical properties of whole heart and myocytes were studied with respect to an untreated control group (Ctrl) using electrocardiographic recordings in vivo, ex vivo perfused hearts, and single-cell patch-clamp analysis. Additionally, a newly developed algorithm was introduced to obtain detailed information of the impact of high glucose on AP profile. Compared to Ctrl, hyperglycemia in STZ-treated animals was coupled with prolongation of the QT interval, enhanced temporal dispersion of electrical recovery, and susceptibility to ventricular arrhythmias, defects observed, in part, in the Akita mutant mouse model of type I diabetes. AP was prolonged and beat-to-beat variability of repolarization was enhanced in diabetic myocytes, with respect to Ctrl cells. Density of Kv K(+) and L-type Ca(2+) currents were decreased in STZ myocytes, in comparison to cells from normoglycemic mice. Pharmacological reduction of Kv currents in Ctrl cells lengthened AP duration and increased temporal dispersion of repolarization, reiterating features identified in diabetic myocytes. CONCLUSIONS Reductions in the repolarizing K(+) currents may contribute to electrical disturbances of the diabetic heart.
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Affiliation(s)
- Marianna Meo
- Division of Cardiovascular Medicine, Departments of Anesthesia and Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
| | - Olivier Meste
- Laboratoire d'Informatique, Signaux et Systèmes de Sophia Antipolis (I3S), Université Nice Sophia Antipolis, CNRS, Nice, France
| | - Sergio Signore
- Division of Cardiovascular Medicine, Departments of Anesthesia and Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
| | - Andrea Sorrentino
- Division of Cardiovascular Medicine, Departments of Anesthesia and Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
| | - Antonio Cannata
- Division of Cardiovascular Medicine, Departments of Anesthesia and Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
| | - Yu Zhou
- Division of Cardiovascular Medicine, Departments of Anesthesia and Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
| | - Alex Matsuda
- Division of Cardiovascular Medicine, Departments of Anesthesia and Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA Fondazione Cardiocentro Ticino, University of Zurich, Lugano, Switzerland
| | - Marco Luciani
- Division of Cardiovascular Medicine, Departments of Anesthesia and Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
| | - Ramaswamy Kannappan
- Division of Cardiovascular Medicine, Departments of Anesthesia and Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
| | - Polina Goichberg
- Division of Cardiovascular Medicine, Departments of Anesthesia and Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
| | - Annarosa Leri
- Division of Cardiovascular Medicine, Departments of Anesthesia and Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA Fondazione Cardiocentro Ticino, University of Zurich, Lugano, Switzerland
| | - Piero Anversa
- Division of Cardiovascular Medicine, Departments of Anesthesia and Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA Fondazione Cardiocentro Ticino, University of Zurich, Lugano, Switzerland
| | - Marcello Rota
- Division of Cardiovascular Medicine, Departments of Anesthesia and Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA Department of Physiology, New York Medical College, Valhalla, NY
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21
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Signore S, Sorrentino A, Borghetti G, Cannata A, Meo M, Zhou Y, Kannappan R, Pasqualini F, O'Malley H, Sundman M, Tsigkas N, Zhang E, Arranto C, Mangiaracina C, Isobe K, Sena BF, Kim J, Goichberg P, Nahrendorf M, Isom LL, Leri A, Anversa P, Rota M. Late Na(+) current and protracted electrical recovery are critical determinants of the aging myopathy. Nat Commun 2015; 6:8803. [PMID: 26541940 PMCID: PMC4638135 DOI: 10.1038/ncomms9803] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Accepted: 10/02/2015] [Indexed: 12/19/2022] Open
Abstract
The aging myopathy manifests itself with diastolic dysfunction and preserved ejection fraction. We raised the possibility that, in a mouse model of physiological aging, defects in electromechanical properties of cardiomyocytes are important determinants of the diastolic characteristics of the myocardium, independently from changes in structural composition of the muscle and collagen framework. Here we show that an increase in the late Na(+) current (INaL) in aging cardiomyocytes prolongs the action potential (AP) and influences temporal kinetics of Ca(2+) cycling and contractility. These alterations increase force development and passive tension. Inhibition of INaL shortens the AP and corrects dynamics of Ca(2+) transient, cell contraction and relaxation. Similarly, repolarization and diastolic tension of the senescent myocardium are partly restored. Thus, INaL offers inotropic support, but negatively interferes with cellular and ventricular compliance, providing a new perspective of the biology of myocardial aging and the aetiology of the defective cardiac performance in the elderly.
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Affiliation(s)
- Sergio Signore
- Departments of Anesthesia and Medicine and Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, 20 Shattuck Street, Boston, Massachusetts 02115, USA
| | - Andrea Sorrentino
- Departments of Anesthesia and Medicine and Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, 20 Shattuck Street, Boston, Massachusetts 02115, USA
| | - Giulia Borghetti
- Departments of Anesthesia and Medicine and Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, 20 Shattuck Street, Boston, Massachusetts 02115, USA
| | - Antonio Cannata
- Departments of Anesthesia and Medicine and Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, 20 Shattuck Street, Boston, Massachusetts 02115, USA
| | - Marianna Meo
- Departments of Anesthesia and Medicine and Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, 20 Shattuck Street, Boston, Massachusetts 02115, USA
| | - Yu Zhou
- Departments of Anesthesia and Medicine and Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, 20 Shattuck Street, Boston, Massachusetts 02115, USA
| | - Ramaswamy Kannappan
- Departments of Anesthesia and Medicine and Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, 20 Shattuck Street, Boston, Massachusetts 02115, USA
| | - Francesco Pasqualini
- Departments of Anesthesia and Medicine and Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, 20 Shattuck Street, Boston, Massachusetts 02115, USA
| | - Heather O'Malley
- Department of Pharmacology, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Mark Sundman
- Departments of Anesthesia and Medicine and Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, 20 Shattuck Street, Boston, Massachusetts 02115, USA
| | - Nikolaos Tsigkas
- Departments of Anesthesia and Medicine and Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, 20 Shattuck Street, Boston, Massachusetts 02115, USA
| | - Eric Zhang
- Departments of Anesthesia and Medicine and Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, 20 Shattuck Street, Boston, Massachusetts 02115, USA
| | - Christian Arranto
- Departments of Anesthesia and Medicine and Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, 20 Shattuck Street, Boston, Massachusetts 02115, USA
| | - Chiara Mangiaracina
- Departments of Anesthesia and Medicine and Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, 20 Shattuck Street, Boston, Massachusetts 02115, USA
| | - Kazuya Isobe
- Departments of Anesthesia and Medicine and Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, 20 Shattuck Street, Boston, Massachusetts 02115, USA
| | - Brena F Sena
- Center for Systems Biology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114, USA
| | - Junghyun Kim
- Departments of Anesthesia and Medicine and Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, 20 Shattuck Street, Boston, Massachusetts 02115, USA
| | - Polina Goichberg
- Departments of Anesthesia and Medicine and Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, 20 Shattuck Street, Boston, Massachusetts 02115, USA
| | - Matthias Nahrendorf
- Center for Systems Biology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114, USA
| | - Lori L Isom
- Department of Pharmacology, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Annarosa Leri
- Departments of Anesthesia and Medicine and Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, 20 Shattuck Street, Boston, Massachusetts 02115, USA
| | - Piero Anversa
- Departments of Anesthesia and Medicine and Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, 20 Shattuck Street, Boston, Massachusetts 02115, USA
| | - Marcello Rota
- Departments of Anesthesia and Medicine and Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, 20 Shattuck Street, Boston, Massachusetts 02115, USA
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23
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Butler L, Cros C, Oldman KL, Harmer AR, Pointon A, Pollard CE, Abi-Gerges N. Enhanced Characterization of Contractility in Cardiomyocytes During Early Drug Safety Assessment. Toxicol Sci 2015; 145:396-406. [DOI: 10.1093/toxsci/kfv062] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
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24
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Ballou LM, Lin RZ, Cohen IS. Control of cardiac repolarization by phosphoinositide 3-kinase signaling to ion channels. Circ Res 2015; 116:127-37. [PMID: 25552692 DOI: 10.1161/circresaha.116.303975] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Upregulation of phosphoinositide 3-kinase (PI3K) signaling is a common alteration in human cancer, and numerous drugs that target this pathway have been developed for cancer treatment. However, recent studies have implicated inhibition of the PI3K signaling pathway as the cause of a drug-induced long-QT syndrome in which alterations in several ion currents contribute to arrhythmogenic drug activity. Surprisingly, some drugs that were thought to induce long-QT syndrome by direct block of the rapid delayed rectifier (IKr) also seem to inhibit PI3K signaling, an effect that may contribute to their arrhythmogenicity. The importance of PI3K in regulating cardiac repolarization is underscored by evidence that QT interval prolongation in diabetes mellitus also may result from changes in multiple currents because of decreased insulin activation of PI3K in the heart. How PI3K signaling regulates ion channels to control the cardiac action potential is poorly understood. Hence, this review summarizes what is known about the effect of PI3K and its downstream effectors, including Akt, on sodium, potassium, and calcium currents in cardiac myocytes. We also refer to some studies in noncardiac cells that provide insight into potential mechanisms of ion channel regulation by this signaling pathway in the heart. Drug development and safety could be improved with a better understanding of the mechanisms by which PI3K regulates cardiac ion channels and the extent to which PI3K inhibition contributes to arrhythmogenic susceptibility.
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Affiliation(s)
- Lisa M Ballou
- From the Department of Physiology and Biophysics and the Institute for Molecular Cardiology, Stony Brook University, NY (L.M.B., R.Z.L., I.S.C.); and the Medical Service, Northport VA Medical Center, NY (R.Z.L.)
| | - Richard Z Lin
- From the Department of Physiology and Biophysics and the Institute for Molecular Cardiology, Stony Brook University, NY (L.M.B., R.Z.L., I.S.C.); and the Medical Service, Northport VA Medical Center, NY (R.Z.L.).
| | - Ira S Cohen
- From the Department of Physiology and Biophysics and the Institute for Molecular Cardiology, Stony Brook University, NY (L.M.B., R.Z.L., I.S.C.); and the Medical Service, Northport VA Medical Center, NY (R.Z.L.).
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25
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Moc C, Taylor AE, Chesini GP, Zambrano CM, Barlow MS, Zhang X, Gustafsson ÅB, Purcell NH. Physiological activation of Akt by PHLPP1 deletion protects against pathological hypertrophy. Cardiovasc Res 2014; 105:160-70. [PMID: 25411382 DOI: 10.1093/cvr/cvu243] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
AIMS To examine the role of physiological Akt signalling in pathological hypertrophy through analysis of PHLPP1 (PH domain leucine-rich repeat protein phosphatase) knock-out (KO) mice. METHODS AND RESULTS To investigate the in vivo requirement for 'physiological' control of Akt activation in cardiac growth, we examined the effect of deleting the Akt phosphatase, PHLPP, on the induction of cardiac hypertrophy. Basal Akt phosphorylation increased nearly two-fold in the cardiomyocytes from PHLPP1 KO mice and physiological hypertrophy induced by swimming exercise was accentuated as assessed by increased heart size and myocyte cell area. In contrast, the development of pathophysiological hypertrophy induced by pressure overload and assessed by increases in heart size, myocyte cell area, and hypertrophic gene expression was attenuated. This attenuation coincided with decreased fibrosis and cell death in the KO mice. Cast moulding revealed increased capillary density basally in the KO hearts, which was further elevated relative to wild-type mouse hearts in response to pressure overload. In vitro studies with isolated myocytes in co-culture also demonstrated that PHLPP1 deletion in cardiomyocytes can enhance endothelial tube formation. Expression of the pro-angiogenic factor VEGF was also elevated basally and accentuated in response to transverse aortic constriction in hearts from KO mice. CONCLUSION Our data suggest that enhancing Akt activity by inhibiting its PHLPP1-mediated dephosphorylation promotes processes associated with physiological hypertrophy that may be beneficial in attenuating the development of pathological hypertrophy.
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Affiliation(s)
- Courtney Moc
- Department of Pharmacology, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0636, USA
| | - Amy E Taylor
- Department of Pharmacology, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0636, USA
| | - Gino P Chesini
- Department of Pharmacology, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0636, USA
| | - Cristina M Zambrano
- Department of Pharmacology, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0636, USA
| | - Melissa S Barlow
- Department of Pharmacology, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0636, USA
| | - Xiaoxue Zhang
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA, USA
| | - Åsa B Gustafsson
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA, USA
| | - Nicole H Purcell
- Department of Pharmacology, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0636, USA
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Naqvi N, Li M, Calvert JW, Tejada T, Lambert JP, Wu J, Kesteven SH, Holman SR, Matsuda T, Lovelock JD, Howard WW, Iismaa SE, Chan AY, Crawford BH, Wagner MB, Martin DIK, Lefer DJ, Graham RM, Husain A. A proliferative burst during preadolescence establishes the final cardiomyocyte number. Cell 2014; 157:795-807. [PMID: 24813607 DOI: 10.1016/j.cell.2014.03.035] [Citation(s) in RCA: 208] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Revised: 01/22/2014] [Accepted: 03/12/2014] [Indexed: 12/11/2022]
Abstract
It is widely believed that perinatal cardiomyocyte terminal differentiation blocks cytokinesis, thereby causing binucleation and limiting regenerative repair after injury. This suggests that heart growth should occur entirely by cardiomyocyte hypertrophy during preadolescence when, in mice, cardiac mass increases many-fold over a few weeks. Here, we show that a thyroid hormone surge activates the IGF-1/IGF-1-R/Akt pathway on postnatal day 15 and initiates a brief but intense proliferative burst of predominantly binuclear cardiomyocytes. This proliferation increases cardiomyocyte numbers by ~40%, causing a major disparity between heart and cardiomyocyte growth. Also, the response to cardiac injury at postnatal day 15 is intermediate between that observed at postnatal days 2 and 21, further suggesting persistence of cardiomyocyte proliferative capacity beyond the perinatal period. If replicated in humans, this may allow novel regenerative therapies for heart diseases.
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Affiliation(s)
- Nawazish Naqvi
- Division of Cardiology, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Ming Li
- Victor Chang Cardiac Research Institute, Sydney, NSW 2010, Australia
| | - John W Calvert
- Division of Cardiothoracic Surgery, Department of Surgery, Carlyle Fraser Heart Center, Emory University School of Medicine, Atlanta, GA 30308, USA
| | - Thor Tejada
- Division of Cardiology, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Jonathan P Lambert
- Division of Cardiothoracic Surgery, Department of Surgery, Carlyle Fraser Heart Center, Emory University School of Medicine, Atlanta, GA 30308, USA
| | - Jianxin Wu
- Victor Chang Cardiac Research Institute, Sydney, NSW 2010, Australia
| | - Scott H Kesteven
- Victor Chang Cardiac Research Institute, Sydney, NSW 2010, Australia
| | - Sara R Holman
- Victor Chang Cardiac Research Institute, Sydney, NSW 2010, Australia
| | - Torahiro Matsuda
- Division of Cardiology, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Joshua D Lovelock
- Division of Cardiology, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Wesley W Howard
- Division of Cardiology, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Siiri E Iismaa
- Victor Chang Cardiac Research Institute, Sydney, NSW 2010, Australia; University of New South Wales, Kensington, NSW 2033, Australia
| | - Andrea Y Chan
- Victor Chang Cardiac Research Institute, Sydney, NSW 2010, Australia
| | - Brian H Crawford
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA 30322, USA; Center for Cardiovascular Biology, Children's Healthcare of Atlanta, Atlanta, GA 30322, USA
| | - Mary B Wagner
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA 30322, USA; Center for Cardiovascular Biology, Children's Healthcare of Atlanta, Atlanta, GA 30322, USA
| | - David I K Martin
- Children's Hospital Oakland Research Institute, Oakland, CA 94609, USA
| | - David J Lefer
- Division of Cardiothoracic Surgery, Department of Surgery, Carlyle Fraser Heart Center, Emory University School of Medicine, Atlanta, GA 30308, USA
| | - Robert M Graham
- Victor Chang Cardiac Research Institute, Sydney, NSW 2010, Australia; University of New South Wales, Kensington, NSW 2033, Australia.
| | - Ahsan Husain
- Division of Cardiology, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA.
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27
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Li M, Iismaa SE, Naqvi N, Nicks A, Husain A, Graham RM. Thyroid hormone action in postnatal heart development. Stem Cell Res 2014; 13:582-91. [PMID: 25087894 DOI: 10.1016/j.scr.2014.07.001] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Revised: 06/30/2014] [Accepted: 07/01/2014] [Indexed: 12/16/2022] Open
Abstract
Thyroid hormone is a critical regulator of cardiac growth and development, both in fetal life and postnatally. Here we review the role of thyroid hormone in postnatal cardiac development, given recent insights into its role in stimulating a burst of cardiomyocyte proliferation in the murine heart in preadolescence; a response required to meet the massive increase in circulatory demand predicated by an almost quadrupling of body weight during a period of about 21 days from birth to adolescence. Importantly, thyroid hormone metabolism is altered by chronic diseases, such as heart failure and ischemic heart disease, as well as in very sick children requiring surgery for congenital heart diseases, which results in low T3 syndrome that impairs cardiovascular function and is associated with a poor prognosis. Therapy with T3 or thyroid hormone analogs has been shown to improve cardiac contractility; however, the mechanism is as yet unknown. Given the postnatal cardiomyocyte mitogenic potential of T3, its ability to enhance cardiac function by promoting cardiomyocyte proliferation warrants further consideration.
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Affiliation(s)
- Ming Li
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia
| | - Siiri E Iismaa
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia; University of New South Wales, Kensington, NSW 2033, Australia
| | - Nawazish Naqvi
- Division of Cardiology, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Amy Nicks
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia; University of Leeds, Leeds, LS2 9JT, UK
| | - Ahsan Husain
- Division of Cardiology, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA.
| | - Robert M Graham
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia; University of New South Wales, Kensington, NSW 2033, Australia.
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28
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Pillai VB, Sundaresan NR, Gupta MP. Regulation of Akt signaling by sirtuins: its implication in cardiac hypertrophy and aging. Circ Res 2014; 114:368-78. [PMID: 24436432 DOI: 10.1161/circresaha.113.300536] [Citation(s) in RCA: 190] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Cardiac hypertrophy is a multifactorial disease characterized by multiple molecular alterations. One of these alterations is change in the activity of Akt, which plays a central role in regulating a variety of cellular processes ranging from cell survival to aging. Akt activation is mainly achieved by its binding to phosphatidylinositol (3,4,5)-triphosphate. This results in a conformational change that exposes the kinase domain of Akt for phosphorylation and activation by its upstream kinase, 3-phosphoinositide-dependent protein kinase 1, in the cell membrane. Recent studies have shown that sirtuin isoforms, silent information regulator (SIRT) 1, SIRT3, and SIRT6, play an essential role in the regulation of Akt activation. Although SIRT1 deacetylates Akt to promote phosphatidylinositol (3,4,5)-triphosphate binding and activation, SIRT3 controls reactive oxygen species-mediated Akt activation, and SIRT6 transcriptionally represses Akt at the level of chromatin. In the first part of this review, we discuss the mechanisms by which sirtuins regulate Akt activation and how they influence other post-translational modifications of Akt. In the latter part of the review, we summarize the implications of sirtuin-dependent regulation of Akt signaling in the control of major cellular processes such as cellular growth, angiogenesis, apoptosis, autophagy, and aging, which are involved in the initiation and progression of several diseases.
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Affiliation(s)
- Vinodkumar B Pillai
- From Center of Cardiac Cell Biology and Therapeutics, Committee on Molecular Medicine, University of Chicago, Chicago, IL
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Dostal DE, Feng H, Nizamutdinov D, Golden HB, Afroze SH, Dostal JD, Jacob JC, Foster DM, Tong C, Glaser S, Gerilechaogetu F. Mechanosensing and Regulation of Cardiac Function. ACTA ACUST UNITED AC 2014; 5:314. [PMID: 25485172 PMCID: PMC4255974 DOI: 10.4172/2155-9880.1000314] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The role of mechanical force as an important regulator of structure and function of mammalian cells, tissues, and organs has recently been recognized. However, mechanical overload is a pathogenesis or comorbidity existing in a variety of heart diseases, such as hypertension, aortic regurgitation and myocardial infarction. Physical stimuli sensed by cells are transmitted through intracellular signal transduction pathways resulting in altered physiological responses or pathological conditions. Emerging evidence from experimental studies indicate that β1-integrin and the angiotensin II type I (AT1) receptor play critical roles as mechanosensors in the regulation of heart contraction, growth and leading to heart failure. Integrin link the extracellular matrix and the intracellular cytoskeleton to initiate the mechanical signalling, whereas, the AT1 receptor could be activated by mechanical stress through an angiotensin-II-independent mechanism. Recent studies show that both Integrin and AT1 receptor and their downstream signalling factors including MAPKs, AKT, FAK, ILK and GTPase regulate heart function in cardiac myocytes. In this review we describe the role of mechanical sensors residing within the plasma membrane, mechanical sensor induced downstream signalling factors and its potential roles in cardiac contraction and growth.
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Affiliation(s)
- David E Dostal
- Central Texas Veterans Health Care System, Temple, Texas, USA ; Division of Molecular Cardiology, Cardiovascular Research Institute, Texas A&M University Health Science Centre, College of Medicine, Temple, Texas, USA
| | - Hao Feng
- Division of Molecular Cardiology, Cardiovascular Research Institute, Texas A&M University Health Science Centre, College of Medicine, Temple, Texas, USA
| | - Damir Nizamutdinov
- Division of Molecular Cardiology, Cardiovascular Research Institute, Texas A&M University Health Science Centre, College of Medicine, Temple, Texas, USA
| | - Honey B Golden
- Division of Molecular Cardiology, Cardiovascular Research Institute, Texas A&M University Health Science Centre, College of Medicine, Temple, Texas, USA
| | - Syeda H Afroze
- Scott & White Healthcare - Digestive Disease Research Centre, Temple, Texas, USA
| | - Joseph D Dostal
- Division of Molecular Cardiology, Cardiovascular Research Institute, Texas A&M University Health Science Centre, College of Medicine, Temple, Texas, USA
| | - John C Jacob
- Division of Molecular Cardiology, Cardiovascular Research Institute, Texas A&M University Health Science Centre, College of Medicine, Temple, Texas, USA
| | - Donald M Foster
- Central Texas Veterans Health Care System, Temple, Texas, USA
| | - Carl Tong
- Systems Biology and Translational Medicine, the Texas A&M University Health Science Centre, College of Medicine, Temple, Texas, USA
| | - Shannon Glaser
- Central Texas Veterans Health Care System, Temple, Texas, USA ; Scott & White Healthcare - Digestive Disease Research Centre, Temple, Texas, USA
| | - Fnu Gerilechaogetu
- Division of Molecular Cardiology, Cardiovascular Research Institute, Texas A&M University Health Science Centre, College of Medicine, Temple, Texas, USA
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31
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Moschella PC, McKillop J, Pleasant DL, Harston RK, Balasubramanian S, Kuppuswamy D. mTOR complex 2 mediates Akt phosphorylation that requires PKCε in adult cardiac muscle cells. Cell Signal 2013; 25:1904-12. [PMID: 23673367 PMCID: PMC3704180 DOI: 10.1016/j.cellsig.2013.05.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Accepted: 05/06/2013] [Indexed: 01/28/2023]
Abstract
Our earlier work showed that mammalian target of rapamycin (mTOR) is essential to the development of various hypertrophic responses, including cardiomyocyte survival. mTOR forms two independent complexes, mTORC1 and mTORC2, by associating with common and distinct cellular proteins. Both complexes are sensitive to a pharmacological inhibitor, torin1, although only mTORC1 is inhibited by rapamycin. Since mTORC2 is known to mediate the activation of a prosurvival kinase, Akt, we analyzed whether mTORC2 directly mediates Akt activation or whether it requires the participation of another prosurvival kinase, PKCε (epsilon isoform of protein kinase-C). Our studies reveal that treatment of adult feline cardiomyocytes in vitro with insulin results in Akt phosphorylation at S473 for its activation which could be augmented with rapamycin but blocked by torin1. Silencing the expression of Rictor (rapamycin-insensitive companion of mTOR), an mTORC2 component, with a sh-RNA in cardiomyocytes lowers both insulin-stimulated Akt and PKCε phosphorylation. Furthermore, phosphorylation of PKCε and Akt at the critical S729 and S473 sites respectively was blocked by torin1 or Rictor knockdown but not by rapamycin, indicating that the phosphorylation at these specific sites occurs downstream of mTORC2. Additionally, expression of DN-PKCε significantly lowered the insulin-stimulated Akt S473 phosphorylation, indicating an upstream role for PKCε in the Akt activation. Biochemical analyses also revealed that PKCε was part of Rictor but not Raptor (a binding partner and component of mTORC1). Together, these studies demonstrate that mTORC2 mediates prosurvival signaling in adult cardiomyocytes where PKCε functions downstream of mTORC2 leading to Akt activation.
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Affiliation(s)
- Phillip C. Moschella
- Cardiology Division of the Department of Medicine, Gazes Cardiac Research Institute, Medical University of South Carolina, Charleston, SC 29425-2221
| | - John McKillop
- Cardiology Division of the Department of Medicine, Gazes Cardiac Research Institute, Medical University of South Carolina, Charleston, SC 29425-2221
| | - Dorea L. Pleasant
- Cardiology Division of the Department of Medicine, Gazes Cardiac Research Institute, Medical University of South Carolina, Charleston, SC 29425-2221
| | - Rebecca K. Harston
- Cardiology Division of the Department of Medicine, Gazes Cardiac Research Institute, Medical University of South Carolina, Charleston, SC 29425-2221
| | - Sundaravadivel Balasubramanian
- Cardiology Division of the Department of Medicine, Gazes Cardiac Research Institute, Medical University of South Carolina, Charleston, SC 29425-2221
| | - Dhandapani Kuppuswamy
- Cardiology Division of the Department of Medicine, Gazes Cardiac Research Institute, Medical University of South Carolina, Charleston, SC 29425-2221
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32
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Signore S, Sorrentino A, Ferreira-Martins J, Kannappan R, Shafaie M, Del Ben F, Isobe K, Arranto C, Wybieralska E, Webster A, Sanada F, Ogórek B, Zheng H, Liu X, Del Monte F, D'Alessandro DA, Wunimenghe O, Michler RE, Hosoda T, Goichberg P, Leri A, Kajstura J, Anversa P, Rota M. Inositol 1, 4, 5-trisphosphate receptors and human left ventricular myocytes. Circulation 2013; 128:1286-97. [PMID: 23983250 DOI: 10.1161/circulationaha.113.002764] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
BACKGROUND Little is known about the function of inositol 1,4,5-trisphosphate receptors (IP3Rs) in the adult heart experimentally. Moreover, whether these Ca(2+) release channels are present and play a critical role in human cardiomyocytes remains to be defined. IP3Rs may be activated after Gαq-protein-coupled receptor stimulation, affecting Ca(2+) cycling, enhancing myocyte performance, and potentially favoring an increase in the incidence of arrhythmias. METHODS AND RESULTS IP3R function was determined in human left ventricular myocytes, and this analysis was integrated with assays in mouse myocytes to identify the mechanisms by which IP3Rs influence the electric and mechanical properties of the myocardium. We report that IP3Rs are expressed and operative in human left ventricular myocytes. After Gαq-protein-coupled receptor activation, Ca(2+) mobilized from the sarcoplasmic reticulum via IP3Rs contributes to the decrease in resting membrane potential, prolongation of the action potential, and occurrence of early afterdepolarizations. Ca(2+) transient amplitude and cell shortening are enhanced, and extrasystolic and dysregulated Ca(2+) elevations and contractions become apparent. These alterations in the electromechanical behavior of human cardiomyocytes are coupled with increased isometric twitch of the myocardium and arrhythmic events, suggesting that Gαq-protein-coupled receptor activation provides inotropic reserve, which is hampered by electric instability and contractile abnormalities. Additionally, our findings support the notion that increases in Ca(2+) load by IP3Rs promote Ca(2+) extrusion by forward-mode Na(+)/Ca(2+) exchange, an important mechanism of arrhythmic events. CONCLUSIONS The Gαq-protein/coupled receptor/IP3R axis modulates the electromechanical properties of the human myocardium and its propensity to develop arrhythmias.
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Affiliation(s)
- Sergio Signore
- Departments of Anesthesia and Medicine and Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (S.S., A.S., J.F.-M., R.K., M.S., F.D.B., K.I., C.A., E.W., A.W., F.S., B.O., H.Z., X.L., T.H., P.G., A.L., J.K., P.A., M.R.); Cardiovascular Institute, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA (F.d.M.); and Department of Cardiovascular and Thoracic Surgery, Montefiore Medical Center, Albert Einstein College of Medicine, New York, NY (D.A.D., O.W., R.E.M.)
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Anthrax lethal toxin induces acute diastolic dysfunction in rats through disruption of the phospholamban signaling network. Int J Cardiol 2013; 168:3884-95. [PMID: 23907041 DOI: 10.1016/j.ijcard.2013.06.050] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Revised: 05/09/2013] [Accepted: 06/28/2013] [Indexed: 01/08/2023]
Abstract
BACKGROUND Anthrax lethal toxin (LT), secreted by Bacillus anthracis, causes severe cardiac dysfunction by unknown mechanisms. LT specifically cleaves the docking domains of MAPKK (MEKs); thus, we hypothesized that LT directly impairs cardiac function through dysregulation of MAPK signaling mechanisms. METHODS AND RESULTS In a time-course study of LT toxicity, echocardiography revealed acute diastolic heart failure accompanied by pulmonary regurgitation and left atrial dilation in adult Sprague-Dawley rats at time points corresponding to dysregulated JNK, phospholamban (PLB) and protein phosphatase 2A (PP2A) myocardial signaling. Using isolated rat ventricular myocytes, we identified the MEK7-JNK1-PP2A-PLB signaling axis to be important for regulation of intracellular calcium (Ca(2+)(i)) handling, PP2A activation and targeting of PP2A-B56α to Ca(2+)(i) handling proteins, such as PLB. Through a combination of gain-of-function and loss-of-function studies, we demonstrated that over-expression of MEK7 protects against LT-induced PP2A activation and Ca(2+)(i) dysregulation through activation of JNK1. Moreover, targeted phosphorylation of PLB-Thr(17) by Akt improved sarcoplasmic reticulum Ca(2+)(i) release and reuptake during LT toxicity. Co-immunoprecipitation experiments further revealed the pivotal role of MEK7-JNK-Akt complex formation for phosphorylation of PLB-Thr(17) during acute LT toxicity. CONCLUSIONS Our findings support a cardiogenic mechanism of LT-induced diastolic dysfunction, by which LT disrupts JNK1 signaling and results in Ca(2+)(i) dysregulation through diminished phosphorylation of PLB by Akt and increased dephosphorylation of PLB by PP2A. Integration of the MEK7-JNK1 signaling module with Akt represents an important stress-activated signalosome that may confer protection to sustain cardiac contractility and maintain normal levels of Ca(2+)(i) through PLB-T(17) phosphorylation.
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Abstract
The possibility of using stem cells to regenerate damaged myocardium has been actively investigated since the late 1990s. Consistent with the traditional view that the heart is a "postmitotic" organ that possesses minimal capacity for self-repair, much of the preclinical and clinical work has focused exclusively on introducing stem cells into the heart, with the hope of differentiation of these cells into functioning cardiomyocytes. This approach is ongoing and retains promise but to date has yielded inconsistent successes. More recently, it has become widely appreciated that the heart possesses endogenous repair mechanisms that, if adequately stimulated, might regenerate damaged cardiac tissue from in situ cardiac stem cells. Accordingly, much recent work has focused on engaging and enhancing endogenous cardiac repair mechanisms. This article reviews the literature on stem cell-based myocardial regeneration, placing emphasis on the mutually enriching interaction between basic and clinical research.
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Affiliation(s)
- Ramesh Mazhari
- The George Washington University School of Medicine, Washington, DC 20037, USA
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Maillet M, van Berlo JH, Molkentin JD. Molecular basis of physiological heart growth: fundamental concepts and new players. Nat Rev Mol Cell Biol 2013; 14:38-48. [PMID: 23258295 PMCID: PMC4416212 DOI: 10.1038/nrm3495] [Citation(s) in RCA: 376] [Impact Index Per Article: 34.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The heart hypertrophies in response to developmental signals as well as increased workload. Although adult-onset hypertrophy can ultimately lead to disease, cardiac hypertrophy is not necessarily maladaptive and can even be beneficial. Progress has been made in our understanding of the structural and molecular characteristics of physiological cardiac hypertrophy, as well as of the endocrine effectors and associated signalling pathways that regulate it. Physiological hypertrophy is initiated by finite signals, which include growth hormones (such as thyroid hormone, insulin, insulin-like growth factor 1 and vascular endothelial growth factor) and mechanical forces that converge on a limited number of intracellular signalling pathways (such as PI3K, AKT, AMP-activated protein kinase and mTOR) to affect gene transcription, protein translation and metabolism. Harnessing adaptive signalling mediators to reinvigorate the diseased heart could have important medical ramifications.
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Affiliation(s)
- Marjorie Maillet
- Department of Pediatrics, University of Cincinnati, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229, USA
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Martelli AM, Tabellini G, Bressanin D, Ognibene A, Goto K, Cocco L, Evangelisti C. The emerging multiple roles of nuclear Akt. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2012; 1823:2168-78. [PMID: 22960641 DOI: 10.1016/j.bbamcr.2012.08.017] [Citation(s) in RCA: 143] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2012] [Revised: 08/20/2012] [Accepted: 08/23/2012] [Indexed: 12/26/2022]
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Affiliation(s)
- Nina Mann
- Cardiovascular Division, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
- Harvard/MIT Health Sciences and Technology Program, Boston, MA
| | - Anthony Rosenzweig
- Cardiovascular Division, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
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Li C, Hua F, Ha T, Singh K, Lu C, Kalbfleisch J, Breuel KF, Ford T, Kao RL, Gao M, Ozment TR, Williams DL. Activation of myocardial phosphoinositide-3-kinase p110α ameliorates cardiac dysfunction and improves survival in polymicrobial sepsis. PLoS One 2012; 7:e44712. [PMID: 23028587 PMCID: PMC3446980 DOI: 10.1371/journal.pone.0044712] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2012] [Accepted: 08/07/2012] [Indexed: 01/04/2023] Open
Abstract
Phosphoinositide-3-kinase (PI3K)/Akt dependent signaling has been shown to improve outcome in sepsis/septic shock. There is also ample evidence that PI3K/Akt dependent signaling plays a crucial role in maintaining normal cardiac function. We hypothesized that PI3K/Akt signaling may ameliorate septic shock by attenuating sepsis-induced cardiac dysfunction. Cardiac function and survival were evaluated in transgenic mice with cardiac myocyte specific expression of constitutively active PI3K isoform, p110α (caPI3K Tg). caPI3K Tg and wild type (WT) mice were subjected to cecal ligation/puncture (CLP) induced sepsis. Wild type CLP mice showed dramatic cardiac dysfunction at 6 hrs. Septic cardiomyopathy was significantly attenuated in caPI3K CLP mice. The time to 100% mortality was 46 hrs in WT CLP mice. In contrast, 80% of the caPI3K mice survived at 46 hrs after CLP (p<0.01) and 50% survived >30 days (p<0.01). Cardiac caPI3K expression prevented expression of an inflammatory phenotype in CLP sepsis. Organ neutrophil infiltration and lung apoptosis were also effectively inhibited by cardiac PI3k p110α expression. Cardiac high mobility group box–1 (HMGB-1) translocation was also inhibited by caPI3K p110α expression. We conclude that cardiac specific activation of PI3k/Akt dependent signaling can significantly modify the morbidity and mortality associated with sepsis. Our data also indicate that myocardial function/dysfunction plays a prominent role in the pathogenesis of sepsis and that maintenance of cardiac function during sepsis is essential. Finally, these data suggest that modulation of the PI3K/p110α signaling pathway may be beneficial in the prevention and/or management of septic cardiomyopathy and septic shock.
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Affiliation(s)
- Chuanfu Li
- Department of Surgery, Quillen College of Medicine, East Tennessee State University, Johnson City, Tennessee, United States of America
| | - Fang Hua
- Department of Emergency Medicine, Emory University School of Medicine Atlanta, Georgia, United States of America
| | - Tuanzhu Ha
- Department of Surgery, Quillen College of Medicine, East Tennessee State University, Johnson City, Tennessee, United States of America
| | - Krishna Singh
- Department of Biomedical Sciences, Quillen College of Medicine, East Tennessee State University, Johnson City, Tennessee, United States of America
| | - Chen Lu
- Department of Surgery, Quillen College of Medicine, East Tennessee State University, Johnson City, Tennessee, United States of America
| | - John Kalbfleisch
- Department of Biometry and Medical Computing, Quillen College of Medicine, East Tennessee State University, Johnson City, Tennessee, United States of America
| | - Kevin F. Breuel
- Department of Obstetrics and Gynecology, Quillen College of Medicine, East Tennessee State University, Johnson City, Tennessee, United States of America
| | - Tiffany Ford
- Department of Obstetrics and Gynecology, Quillen College of Medicine, East Tennessee State University, Johnson City, Tennessee, United States of America
| | - Race L. Kao
- Department of Surgery, Quillen College of Medicine, East Tennessee State University, Johnson City, Tennessee, United States of America
- Department of Emergency Medicine, Emory University School of Medicine Atlanta, Georgia, United States of America
| | - Ming Gao
- Department of Surgery, Quillen College of Medicine, East Tennessee State University, Johnson City, Tennessee, United States of America
| | - Tammy R. Ozment
- Department of Surgery, Quillen College of Medicine, East Tennessee State University, Johnson City, Tennessee, United States of America
| | - David L. Williams
- Department of Surgery, Quillen College of Medicine, East Tennessee State University, Johnson City, Tennessee, United States of America
- * E-mail:
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Chen Y, Zhao J, Du J, Xu G, Tang C, Geng B. Hydrogen sulfide regulates cardiac sarcoplasmic reticulum Ca(2+) uptake via K(ATP) channel and PI3K/Akt pathway. Life Sci 2012; 91:271-8. [PMID: 22884808 DOI: 10.1016/j.lfs.2012.07.026] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2012] [Revised: 07/05/2012] [Accepted: 07/13/2012] [Indexed: 12/18/2022]
Abstract
AIMS To investigate the effects of hydrogen sulfide (H(2)S) on calcium uptake activity of the rat cardiac sarcoplasmic reticulum (SR) and possible signaling. MAIN METHODS Crude SR was isolated after treatment with H(2)S, then SR Ca(2+) uptake and SR Ca(2+)-ATPase (SERCA) activity was measured by the isotopic tracer method. The possible roles of the K(ATP) channel and PI3K/Akt and SR-membrane protein phospholamban (PLB) pathway were analyzed by specific blockers, and target protein activation was assayed by measuring protein phosphorylation. KEY FINDINGS Exogenous H(2)S lowered Ca(2+) uptake into the SR time or concentration dependently, which was associated with decreased SERCA activity. Inhibiting endogenous H(2)S production by DL-propargylglycine increased SR Ca(2+) uptake and SERCA activity. H(2)S inhibition of PLB phosphorylation was through SERCA activity and was reversed by two PI3K inhibitors, wortmannin and LY294002. Glibenclamide (a K(ATP) channel blocker) blocked the inhibitory effects of H(2)S on PLB and Akt phosphorylation. Pinacidil (a K(ATP) channel opener) reduced the phosphorylation of PLB and reversed the effects of DL-propargylglycine. H(2)S preconditioning increased PLB phosphorylation but did not affect SERCA activity. SIGNIFICANCE Endogenous H(2)S transiently and reversibly inhibits SR Ca(2+) uptake in rat heart SR because of downregulated SERCA activity associated with PLB phosphorylation by the PI3K/Akt or K(ATP) channel. The transient negative regulation of SR Ca(2+) uptake and the L-type Ca(2+) channel contributes to Ca(2+) cycle homeostasis, which might be an important molecular mechanism in ischemic diseases.
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Affiliation(s)
- Yu Chen
- Department of Physiology and Pathophysiology, School of Basic Medical Science, Peking University, PR China
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Klement GL, Goukassian D, Hlatky L, Carrozza J, Morgan JP, Yan X. Cancer Therapy Targeting the HER2-PI3K Pathway: Potential Impact on the Heart. Front Pharmacol 2012; 3:113. [PMID: 22754526 PMCID: PMC3384262 DOI: 10.3389/fphar.2012.00113] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2012] [Accepted: 05/24/2012] [Indexed: 01/22/2023] Open
Abstract
The HER2-PI3K pathway is the one of the most mutated pathways in cancer. Several drugs targeting the major kinases of this pathway have been approved by the Food and Drug Administration and many are being tested in clinical trials for the treatment of various cancers. However, the HER2-PI3K pathway is also pivotal for maintaining the physiological function of the heart, especially in the presence of cardiac stress. Clinical studies have shown that in patients treated with doxorubicin concurrently with Trastuzumab, a monoclonal antibody that blocks the HER2 receptor, the New York Heart Association class III/IV heart failure was significantly increased compared to those who were treated with doxorubicin alone (16 vs. 3%). Studies in transgenic mice have also shown that other key kinases of this pathway, such as PI3Kα, PDK1, Akt, and mTOR, are important for protecting the heart from ischemia-reperfusion and aortic stenosis induced cardiac dysfunction. Studies, however, have also shown that inhibition of PI3Kγ improve cardiac function of a failing heart. In addition, results from transgenic mouse models are not always consistent with the outcome of the pharmacological inhibition of this pathway. Here, we will review these findings and discuss how we can address the cardiac side-effects caused by inhibition of this important pathway in both cancer and cardiac biology.
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Affiliation(s)
- Giannoula L Klement
- Center of Cancer Systems Biology, St. Elizabeth's Medical Center, Tufts University School of Medicine Boston, MA, USA
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Duran JM, Taghavi S, Berretta RM, Makarewich CA, Sharp Iii T, Starosta T, Udeshi F, George JC, Kubo H, Houser SR. A characterization and targeting of the infarct border zone in a swine model of myocardial infarction. Clin Transl Sci 2012; 5:416-21. [PMID: 23067355 DOI: 10.1111/j.1752-8062.2012.00432.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
INTRODUCTION Novel therapies for myocardial infarction (MI) involving stem cells, gene therapy, biomaterials, or revascularization strategies have shown promise in animal studies and clinical trials, but results have been limited partially due to the injection of therapeutics into ischemic myocardium that cannot support their mechanism of action. Accurate targeting of therapeutics precisely to the infarct border zone (BZ) may be essential for effective repair of the ischemic heart. METHODS Ischemia-reperfusion MI was induced in Yorkshire swine by inflation of an angioplasty balloon in the left anterior descending coronary artery. Fluorescent microspheres were injected into the BZ under NOGA catheter guidance, and this location was identified grossly then examined by immunohistochemistry and Western analysis. RESULTS Analysis of the infarct zone two hours post-MI revealed a frankly necrotic region devoid of contractile proteins with marked activation of caspase-3. The NOGA-defined BZ closely approximates the grossly-defined BZ and contains intact myocytes and vasculature. Western analysis detected Akt expression and levels of Ca(2+) handling proteins equivalent to that of viable tissues. CONCLUSIONS Histological and Western analysis revealed that NOGA mapping precisely identifies grossly and molecularly defined infarct BZ at a location where there are still viable cells and vessels capable of supporting novel therapeutic strategies.
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Affiliation(s)
- Jason M Duran
- Temple University School of Medicine, Cardiovascular Research Center, Temple University, PA, USA
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Excitation-contraction coupling in ventricular myocytes is enhanced by paracrine signaling from mesenchymal stem cells. J Mol Cell Cardiol 2012; 52:1249-56. [PMID: 22465692 DOI: 10.1016/j.yjmcc.2012.03.008] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2011] [Revised: 02/14/2012] [Accepted: 03/12/2012] [Indexed: 12/17/2022]
Abstract
In clinical trials mesenchymal stem cells (MSCs) are transplanted into cardiac ischemic regions to decrease infarct size and improve contractility. However, the mechanism and time course of MSC-mediated cardioprotection are incompletely understood. We tested the hypothesis that paracrine signaling by MSCs promotes changes in cardiac excitation-contraction (EC) coupling that protects myocytes from cell death and enhances contractility. Isolated mouse ventricular myocytes (VMs) were treated with control tyrode, MSC conditioned-tyrode (ConT) or co-cultured with MSCs. The Ca handling properties of VMs were monitored by laser scanning confocal microscopy and whole cell voltage clamp. ConT superfusion of VMs resulted in a time dependent increase of the Ca transient amplitude (ConT(15min): ΔF/F(0)=3.52±0.38, n=14; Ctrl(15min): ΔF/F(0)=2.41±0.35, n=14) and acceleration of the Ca transient decay (τ: ConT: 269±18ms n=14; vs. Ctrl: 315±57ms, n=14). Voltage clamp recordings confirmed a ConT induced increase in I(Ca,L) (ConT: -5.9±0.5 pA/pF n=11; vs. Ctrl: -4.04±0.3 pA/pF, n=12). The change of τ resulted from increased SERCA activity. Changes in the Ca transient amplitude and τ were prevented by the PI3K inhibitors Wortmannin (100nmol/L) and LY294002 (10μmol/L) and the Akt inhibitor V (20μmol/L) indicating regulation through PI3K signal transduction and Akt activation which was confirmed by western blotting. A change in τ was also prevented in eNOS(-/-) myocytes or by inhibition of eNOS suggesting an NO mediated regulation of SERCA activity. Since paracrine signaling further resulted in increased survival of VMs we propose that the Akt induced change in Ca signaling is also a mechanism by which MSCs mediate an anti-apoptotic effect.
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Mohsin S, Siddiqi S, Collins B, Sussman MA. Empowering adult stem cells for myocardial regeneration. Circ Res 2012; 109:1415-28. [PMID: 22158649 DOI: 10.1161/circresaha.111.243071] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Treatment strategies for heart failure remain a high priority for ongoing research due to the profound unmet need in clinical disease coupled with lack of significant translational progress. The underlying issue is the same whether the cause is acute damage, chronic stress from disease, or aging: progressive loss of functional cardiomyocytes and diminished hemodynamic output. To stave off cardiomyocyte losses, a number of strategic approaches have been embraced in recent years involving both molecular and cellular approaches to augment myocardial structure and performance. Resultant excitement surrounding regenerative medicine in the heart has been tempered by realizations that reparative processes in the heart are insufficient to restore damaged myocardium to normal functional capacity and that cellular cardiomyoplasty is hampered by poor survival, proliferation, engraftment, and differentiation of the donated population. To overcome these limitations, a combination of molecular and cellular approaches must be adopted involving use of genetic engineering to enhance resistance to cell death and increase regenerative capacity. This review highlights biological properties of approached to potentiate stem cell-mediated regeneration to promote enhanced myocardial regeneration, persistence of donated cells, and long-lasting tissue repair. Optimizing cell delivery and harnessing the power of survival signaling cascades for ex vivo genetic modification of stem cells before reintroduction into the patient will be critical to enhance the efficacy of cellular cardiomyoplasty. Once this goal is achieved, then cell-based therapy has great promise for treatment of heart failure to combat the loss of cardiac structure and function associated with acute damage, chronic disease, or aging.
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Li X, Mikhalkova D, Gao E, Zhang J, Myers V, Zincarelli C, Lei Y, Song J, Koch WJ, Peppel K, Cheung JY, Feldman AM, Chan TO. Myocardial injury after ischemia-reperfusion in mice deficient in Akt2 is associated with increased cardiac macrophage density. Am J Physiol Heart Circ Physiol 2011; 301:H1932-40. [PMID: 21890689 DOI: 10.1152/ajpheart.00755.2010] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Akt2 protein kinase has been shown to promote cell migration and actin polymerization in several cell types, including macrophages. Because migrating macrophages constitute an important inflammatory response after myocardial ischemia, we determined cardiac macrophage expression after ischemia-reperfusion (I/R) injury and cryo-injury in mice lacking Akt2 (Akt2-KO). At 7 days post-I/R, Akt2-KO cardiac tissues showed an increase in immunohistochemical staining for macrophage markers (Galectin 3 and F4/80) compared with wild-type (WT) mice, indicating macrophage density was increased in the injured Akt2-KO myocardium. This change was time dependent because macrophage density was similar between WT and Akt2-KO myocardium at 3 days post-I/R, but by 7 and 14 days post-I/R, macrophage density was significantly increased in Akt2-KO myocardium. Concomitantly, infarct size was larger and cardiac function was reduced in Akt2-KO mice subjected to I/R. However, when cryo-infarction produced similar infarct sizes in the anterior wall in both WT and Akt2-KO mice, macrophage density remained higher in Akt2-KO mouse myocardium, suggesting Akt2 regulates myocardial macrophage density independent of infarct size. Consistently, bone marrow from Akt2-KO mice enhanced myocardial macrophage density in both C57/B6 WT and Akt2-KO recipient mice. Finally, reciprocal ex-vivo coculturing of macrophages and cardiac myocytes showed that activated Akt2-KO peritoneal macrophages had reduced mobility and adhesion when compared with WT littermate controls. Thus, although Akt-2 KO mice did not affect the initial inflammation response after injury and Akt2 deficiency has been shown to impair cell migration or motility in macrophages, our data suggested a novel mechanism in which increasing retention of Akt2-KO macrophages resulted in increasing cardiac Akt2-KO macrophage density in the myocardial space.
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Affiliation(s)
- Xue Li
- Center for Translational Medicine, Department of Medicine, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
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Abstract
This review article addresses the controversy as to whether the adult heart possesses an intrinsic growth reserve. If myocyte renewal takes place in healthy and diseased organs, the reconstitution of the damaged tissue lost upon pathological insults might be achieved by enhancing a natural occurring process. Evidence in support of the old and new view of cardiac biology is critically discussed in an attempt to understand whether the heart is a static or dynamic organ. According to the traditional concept, the heart exerts its function until death of the organism with the same or lesser number of cells that are present at birth. This paradigm was challenged by documentation of the cell cycle activation and nuclear and cellular division in a subset of myocytes. These observations raised the important question of the origin of replicating myocytes. Several theories have been proposed and are presented in this review article. Newly formed myocytes may derive from a pre-existing pool of cells that has maintained the ability to divide. Alternatively, myocytes may be generated by activation and commitment of resident cardiac stem cells or by migration of progenitor cells from distant organs. In all cases, parenchymal cell turnover throughout lifespan results in a heterogeneous population consisting of young, adult, and senescent myocytes. With time, accumulation of old myocytes has detrimental effects on cardiac performance and may cause the development of an aging myopathy.
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Affiliation(s)
- T Hosoda
- Division of Cardiovascular Medicine, Department of Anesthesia and Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
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Sussman MA, Völkers M, Fischer K, Bailey B, Cottage CT, Din S, Gude N, Avitabile D, Alvarez R, Sundararaman B, Quijada P, Mason M, Konstandin MH, Malhowski A, Cheng Z, Khan M, McGregor M. Myocardial AKT: the omnipresent nexus. Physiol Rev 2011; 91:1023-70. [PMID: 21742795 PMCID: PMC3674828 DOI: 10.1152/physrev.00024.2010] [Citation(s) in RCA: 180] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
One of the greatest examples of integrated signal transduction is revealed by examination of effects mediated by AKT kinase in myocardial biology. Positioned at the intersection of multiple afferent and efferent signals, AKT exemplifies a molecular sensing node that coordinates dynamic responses of the cell in literally every aspect of biological responses. The balanced and nuanced nature of homeostatic signaling is particularly essential within the myocardial context, where regulation of survival, energy production, contractility, and response to pathological stress all flow through the nexus of AKT activation or repression. Equally important, the loss of regulated AKT activity is primarily the cause or consequence of pathological conditions leading to remodeling of the heart and eventual decompensation. This review presents an overview compendium of the complex world of myocardial AKT biology gleaned from more than a decade of research. Summarization of the widespread influence that AKT exerts upon myocardial responses leaves no doubt that the participation of AKT in molecular signaling will need to be reckoned with as a seemingly omnipresent regulator of myocardial molecular biological responses.
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Affiliation(s)
- Mark A Sussman
- Department of Biology, San Diego State University, SDSU Heart Institute, San Diego, California 92182, USA.
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Effects of age and heart failure on human cardiac stem cell function. THE AMERICAN JOURNAL OF PATHOLOGY 2011; 179:349-66. [PMID: 21703415 DOI: 10.1016/j.ajpath.2011.03.036] [Citation(s) in RCA: 162] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2010] [Revised: 02/25/2011] [Accepted: 03/03/2011] [Indexed: 12/11/2022]
Abstract
Currently, it is unknown whether defects in stem cell growth and differentiation contribute to myocardial aging and chronic heart failure (CHF), and whether a compartment of functional human cardiac stem cells (hCSCs) persists in the decompensated heart. To determine whether aging and CHF are critical determinants of the loss in growth reserve of the heart, the properties of hCSCs were evaluated in 18 control and 23 explanted hearts. Age and CHF showed a progressive decrease in functionally competent hCSCs. Chronological age was a major predictor of five biomarkers of hCSC senescence: telomeric shortening, attenuated telomerase activity, telomere dysfunction-induced foci, and p21(Cip1) and p16(INK4a) expression. CHF had similar consequences for hCSCs, suggesting that defects in the balance between cardiomyocyte mass and the pool of nonsenescent hCSCs may condition the evolution of the decompensated myopathy. A correlation was found previously between telomere length in circulating bone marrow cells and cardiovascular diseases, but that analysis was restricted to average telomere length in a cell population, neglecting the fact that telomere attrition does not occur uniformly in all cells. The present study provides the first demonstration that dysfunctional telomeres in hCSCs are biomarkers of aging and heart failure. The biomarkers of cellular senescence identified here can be used to define the birth date of hCSCs and to sort young cells with potential therapeutic efficacy.
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Increased inflammatory signaling and lethality of influenza H1N1 by nuclear thioredoxin-1. PLoS One 2011; 6:e18918. [PMID: 21526215 PMCID: PMC3078150 DOI: 10.1371/journal.pone.0018918] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2010] [Accepted: 03/25/2011] [Indexed: 01/30/2023] Open
Abstract
Background Cell culture studies show that the antioxidant thiol protein, thioredoxin-1 (Trx1), translocates to cell nuclei during stress, facilitates DNA binding of transcription factors NF-κB and glucocorticoid receptor (GR) and potentiates signaling in immune cells. Excessive proinflammatory signaling in vivo contributes to immune hyper-responsiveness and disease severity, but no studies have addressed whether nuclear Trx1 mediates such responses. Methodology/Principal Findings Transgenic mice (Tg) expressing human Trx1 (hTrx1) with added nuclear localization signal (NLS) showed broad tissue expression and nuclear localization. The role of nuclear Trx1 in inflammatory signaling was examined in Tg and wild-type (WT) mice following infection with influenza (H1N1) virus. Results showed that Tg mice had earlier and more extensive NF-κB activation, increased TNF-α and IL-6 expression, greater weight loss, slower recovery and increased mortality compared to WT. Decreased plasma glutathione (GSH) and oxidized plasma GSH/GSSG redox potential (EhGSSG) following infection in Tg mice showed that the increased nuclear thiol antioxidant caused a paradoxical downstream oxidative stress. An independent test of this nuclear reductive stress showed that glucocorticoid-induced thymocyte apoptosis was increased by NLS-Trx1. Conclusion/Significance Increased Trx1 in cell nuclei can increase severity of disease responses by potentiation of redox-sensitive transcription factor activation.
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Fischer KM, Din S, Gude N, Konstandin MH, Wu W, Quijada P, Sussman MA. Cardiac progenitor cell commitment is inhibited by nuclear Akt expression. Circ Res 2011; 108:960-70. [PMID: 21350213 DOI: 10.1161/circresaha.110.237156] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
RATIONALE Stem cell therapies to regenerate damaged cardiac tissue represent a novel approach to treat heart disease. However, the majority of adoptively transferred stem cells delivered to damaged myocardium do not survive long enough to impart protective benefits, resulting in modest functional improvements. Strategies to improve survival and proliferation of stem cells show promise for significantly enhancing cardiac function and regeneration. OBJECTIVE To determine whether injected cardiac progenitor cells (CPCs) genetically modified to overexpress nuclear Akt (CPCeA) increase structural and functional benefits to infarcted myocardium relative to control CPCs. METHODS AND RESULTS CPCeA exhibit significantly increased proliferation and secretion of paracrine factors compared with CPCs. However, CPCeA exhibit impaired capacity for lineage commitment in vitro. Infarcted hearts receiving intramyocardial injection of CPCeA have increased recruitment of endogenous c-kit cells compared with CPCs, but neither population provides long-term functional and structural improvements compared with saline-injected controls. Pharmacological inhibition of Akt alleviated blockade of lineage commitment in CPCeA. CONCLUSIONS Although overexpression of nuclear Akt promotes rapid proliferation and secretion of protective paracrine factors, the inability of CPCeA to undergo lineage commitment hinders their capacity to provide functional or structural benefits to infarcted hearts. Despite enhanced recruitment of endogenous CPCs, lack of functional improvement in CPCeA-treated hearts demonstrates CPC lineage commitment is essential to the regenerative response. Effective stem cell therapies must promote cellular survival and proliferation without inhibiting lineage commitment. Because CPCeA exhibit remarkable proliferative potential, an inducible system mediating nuclear Akt expression could be useful to augment cell therapy approaches.
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Kawaguchi N, Smith AJ, Waring CD, Hasan MK, Miyamoto S, Matsuoka R, Ellison GM. c-kitpos GATA-4 high rat cardiac stem cells foster adult cardiomyocyte survival through IGF-1 paracrine signalling. PLoS One 2010; 5:e14297. [PMID: 21179204 PMCID: PMC3001457 DOI: 10.1371/journal.pone.0014297] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2010] [Accepted: 11/17/2010] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Resident c-kit positive (c-kitpos) cardiac stem cells (CSCs) could be considered the most appropriate cell type for myocardial regeneration therapies. However, much is still unknown regarding their biological properties and potential. METHODOLOGY/PRINCIPAL FINDINGS We produced clones of high and low expressing GATA-4 CSCs from long-term bulk-cultured c-kitpos CSCs isolated from adult rat hearts. When c-kitpos GATA-4 high expressing clonal CSCs (cCSCs) were co-cultured with adult rat ventricular cardiomyocytes, we observed increased survival and contractility of the cardiomyocytes, compared to cardiomyocytes cultured alone, co-cultured with fibroblasts or c-kitpos GATA-4 low expressing cCSCs. When analysed by ELISA, the concentration of IGF-1 was significantly increased in the c-kitpos GATA-4 high cCSC/cardiomyocyte co-cultures and there was a significant correlation between IGF-1 concentration and cardiomyocyte survival. We showed the activation of the IGF-1 receptor and its downstream molecular targets in cardiomyocytes co-cultured with c-kitpos GATA-4 high cCSCs but not in cardiomyocytes that were cultured alone, co-cultured with fibroblasts or c-kitpos GATA-4 low cCSCs. Addition of a blocking antibody specific to the IGF-1 receptor inhibited the survival of cardiomyocytes and prevented the activation of its signalling in cardiomyocytes in the c-kitpos GATA-4 high cCSC/cardiomyocyte co-culture system. IGF-1 supplementation or IGF-1 high conditioned medium taken from the co-culture of c-kitpos GATA-4 high cCSCs plus cardiomyocytes did extend the survival and contractility of cardiomyocytes cultured alone and cardiomyocytes co-cultured with c-kitpos GATA-4 low cCSCs. CONCLUSION/SIGNIFICANCE c-kitpos GATA-4 high cCSCs exert a paracrine survival effect on cardiomyocytes through induction of the IGF-1R and signalling pathway.
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Affiliation(s)
- Nanako Kawaguchi
- International Research and Educational Institute for Integrated Medical Sciences (IREIIMS), Tokyo Women's Medical University, Tokyo, Japan
| | - Andrew J. Smith
- Stem Cell and Molecular Physiology Laboratory, Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | - Cheryl D. Waring
- Stem Cell and Molecular Physiology Laboratory, Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | - Md Kamrul Hasan
- International Research and Educational Institute for Integrated Medical Sciences (IREIIMS), Tokyo Women's Medical University, Tokyo, Japan
| | - Shinka Miyamoto
- International Research and Educational Institute for Integrated Medical Sciences (IREIIMS), Tokyo Women's Medical University, Tokyo, Japan
- Department of Cardiovascular Surgery, Heart Institute of Japan, Tokyo Women's Medical University, Tokyo, Japan
| | - Rumiko Matsuoka
- International Research and Educational Institute for Integrated Medical Sciences (IREIIMS), Tokyo Women's Medical University, Tokyo, Japan
| | - Georgina M. Ellison
- Stem Cell and Molecular Physiology Laboratory, Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom
- * E-mail:
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