1
|
Zhou P, Yang X, Yang D, Jiang X, Wang WE, Yue R, Fang Y. Integrin-Linked Kinase Activation Prevents Ventricular Arrhythmias Induced by Ischemia/Reperfusion Via Inhibition of Connexin 43 Remodeling. J Cardiovasc Transl Res 2021; 14:610-618. [PMID: 32144627 PMCID: PMC8397684 DOI: 10.1007/s12265-020-09979-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Accepted: 02/24/2020] [Indexed: 12/16/2022]
Abstract
Ischemia reperfusion (I/R)-induced arrhythmia is a serious complication in patients with cardiac infarction. Remodeling of connexin (Cx) 43, manifested as phosphorylation, contributes significantly to arrhythmogenesis. Integrin-linked kinase (ILK) attenuated ventricular remodeling and improved cardiac function in rats after myocardial infarction. We hypothesized that ILK, through Cx43 phosphorylation, would be protective against I/R-induced ventricular arrhythmias. Our study showed that I/R-induced ventricular arrhythmias were attenuated by an ILK agonist LPTP and worsened by the ILK inhibitor Cpd22. I/R disrupted Cx43 distribution, but it was partially normalized in the presence of LPTP. Compared with I/R, the phosphorylation of Akt was increased significantly after pretreatment with LPTP. The increase in phosphorylated Akt was physiologically significant because, in the presence of the Akt inhibitor MK2206, the protective effects of LPTP were blocked. This indicated that ILK activation prevented I/R-induced-ventricular arrhythmia, an effect potentially related to inhibition of Cx43 remodeling via Akt activation.
Collapse
Affiliation(s)
- Ping Zhou
- Department of Cardiology, The First People's Hospital of Chongqing Liang Jiang New Area, Chongqing, 401121, China
- Department of Cardiology, Chongqing Institute of Cardiology, Daping Hospital, Army Medical University, 10 Changjiang Branch Road,Yuzhong District, Chongqing, 400042, China
| | - Xiaoli Yang
- Department of Cardiology, Chongqing Institute of Cardiology, Daping Hospital, Army Medical University, 10 Changjiang Branch Road,Yuzhong District, Chongqing, 400042, China
| | - Dezhong Yang
- Department of Cardiology, Chongqing Institute of Cardiology, Daping Hospital, Army Medical University, 10 Changjiang Branch Road,Yuzhong District, Chongqing, 400042, China
| | - Xin Jiang
- Department of Cardiology, Chongqing Institute of Cardiology, Daping Hospital, Army Medical University, 10 Changjiang Branch Road,Yuzhong District, Chongqing, 400042, China
| | - Wei Eric Wang
- Department of Cardiology, Chongqing Institute of Cardiology, Daping Hospital, Army Medical University, 10 Changjiang Branch Road,Yuzhong District, Chongqing, 400042, China
| | - Rongchuan Yue
- Department of Cardiology, Chongqing Institute of Cardiology, Daping Hospital, Army Medical University, 10 Changjiang Branch Road,Yuzhong District, Chongqing, 400042, China
| | - Yuqiang Fang
- Department of Cardiology, Chongqing Institute of Cardiology, Daping Hospital, Army Medical University, 10 Changjiang Branch Road,Yuzhong District, Chongqing, 400042, China.
| |
Collapse
|
2
|
Network construction of aberrantly expressed miRNAs and their target mRNAs in ventricular myocardium with ischemia-reperfusion arrhythmias. J Cardiothorac Surg 2020; 15:216. [PMID: 32787945 PMCID: PMC7425585 DOI: 10.1186/s13019-020-01262-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Accepted: 08/03/2020] [Indexed: 12/31/2022] Open
Abstract
Background Hypothermic ischemia-reperfusion arrhythmia remains the main factor affecting cardiac resuscitation under cardiopulmonary bypass. Existing research shows that certain miRNAs exhibit significantly different expressions and effects in arrhythmias, however, the effect of miRNAs on the progression of hypothermic ischemic–reperfusion arrhythmias (RA) and its potential mechanism remain to be further explored. Methods Sprague-Dawley (SD) rats were randomly divided into two groups (n = 8): a normal control group (Group C) and a hypothermic ischemia-reperfusion group (Group IR), which were used to establish a Langendorff isolated cardiac perfusion model. According to the arrhythmia scoring system, rats in group IR were divided into a high-risk group (IR-H) and a low-risk group (IR-L). miRNAs expression profiles of ventricular myocardium with global hypothermic ischemia–reperfusion and those of ventricular myocardium with hypothermic ischemia–RA were established through high-throughput sequencing. Furthermore, the aberrantly expressed miRNAs in myocardium with and without hypothermic ischemia–RA were screened and verified. The target genes of these aberrantly expressed miRNAs were predicted using RNAhybrid and MiRanda software. Based on Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) databases, we determined the mRNA targets associated with these miRNAs and studied the miRNA–mRNA interaction during the cardiovascular disease progression. The aberrantly expressed miRNAs related to hypothermic ischemia–RA were validated by Real-time Quantitative polymerase chain reaction (RT-qPCR). Results Eight significantly aberrantly expressed miRNAs (rno-miR-122-5p, rno-miR-429, novel_miR-1, novel_miR-16, novel_miR-17, novel_miR-19, novel_miR-30, and novel_miR-43) were identified, among which six were up-regulated and two were down-regulated. Moreover, target genes and signaling pathways associated with these aberrantly expressed miRNAs were predicted and analyzed. The miRNA–mRNA interaction network graph showed that GJA1 gene was considered as the target of novel_miR-17. Conclusions Aberrantly expressed miRNAs were possibly associated with the formation mechanism of hypothermic ischemia–RA. Specific miRNAs, such as novel_miR-17 and rno-miR-429 are probably new potential targets for further functional studies of hypothermic ischemia–RA.
Collapse
|
3
|
Foertsch S, Lackner I, Weber B, Füchsl AM, Langgartner D, Wirkert E, Peters S, Fois G, Pressmar J, Fegert JM, Frick M, Gündel H, Kalbitz M, Reber SO. Sensory contact to the stressor prevents recovery from structural and functional heart damage following psychosocial trauma. Brain Behav Immun 2019; 80:667-677. [PMID: 31085218 DOI: 10.1016/j.bbi.2019.05.013] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Revised: 04/18/2019] [Accepted: 05/08/2019] [Indexed: 02/06/2023] Open
Abstract
Cardiovascular disorders (CVD) and posttraumatic stress disorder (PTSD) are highly comorbid, but the underlying mechanisms are not fully understood. Chronic psychosocial stress was induced in male mice by chronic subordinate colony housing (CSC), a pre-clinically validated mouse model for PTSD. Cardiac structure and function were assessed on day 20 of the CSC paradigm. Following CSC, mice were kept in different sensory contact modalities to the last aggressor for 30 days, and development of cardiac function and behavioral aspects were determined. Here we show that psychosocial trauma affects heart structure by disturbing cell-to-cell integrity of cardiomyocytes, causes tachycardia, disturbance of diurnal heart rate rhythmicity and behavioral deficits in a mouse model for PTSD. Structural and functional alterations were also found in cardiomyocytes upon in vitro treatment with pro-inflammatory cytokines typically increased after psychosocial trauma. Interestingly, sensory contact to the aggressor subsequent to psychosocial trauma prohibits functional and structural heart recovery, while isolation was beneficial for cardiac but detrimental for mental health. These findings contribute to our understanding of potential mechanisms underlying the high comorbidity of CVD and PTSD.
Collapse
Affiliation(s)
- Sandra Foertsch
- Laboratory for Molecular Psychosomatics, Department of Psychosomatic Medicine and Psychotherapy, University of Ulm, Ulm, Germany
| | - Ina Lackner
- Department of Traumatology, Hand, Plastic-, and Reconstructive Surgery, Center of Surgery, University of Ulm, Ulm, Germany
| | - Birte Weber
- Laboratory for Molecular Psychosomatics, Department of Psychosomatic Medicine and Psychotherapy, University of Ulm, Ulm, Germany
| | - Andrea M Füchsl
- Laboratory for Molecular Psychosomatics, Department of Psychosomatic Medicine and Psychotherapy, University of Ulm, Ulm, Germany
| | - Dominik Langgartner
- Laboratory for Molecular Psychosomatics, Department of Psychosomatic Medicine and Psychotherapy, University of Ulm, Ulm, Germany
| | - Eva Wirkert
- Laboratory for Molecular Psychosomatics, Department of Psychosomatic Medicine and Psychotherapy, University of Ulm, Ulm, Germany
| | - Sebastian Peters
- Department of Neurology, University Hospital Regensburg, Regensburg, Germany
| | - Giorgio Fois
- Institute of General Physiology, University of Ulm, Ulm, Germany
| | - Jochen Pressmar
- Department of Traumatology, Hand, Plastic-, and Reconstructive Surgery, Center of Surgery, University of Ulm, Ulm, Germany
| | - Jörg M Fegert
- Department of Child and Adolescent Psychiatry and Psychotherapy, University of Ulm, Ulm, Germany
| | - Manfred Frick
- Institute of General Physiology, University of Ulm, Ulm, Germany
| | - Harald Gündel
- Department of Psychosomatic Medicine and Psychotherapy, University of Ulm, Ulm, Germany
| | - Miriam Kalbitz
- Department of Traumatology, Hand, Plastic-, and Reconstructive Surgery, Center of Surgery, University of Ulm, Ulm, Germany
| | - Stefan O Reber
- Laboratory for Molecular Psychosomatics, Department of Psychosomatic Medicine and Psychotherapy, University of Ulm, Ulm, Germany.
| |
Collapse
|
4
|
Cassis P, Cerullo D, Zanchi C, Corna D, Lionetti V, Giordano F, Novelli R, Conti S, Casieri V, Matteucci M, Locatelli M, Taraboletti G, Villa S, Gastoldi S, Remuzzi G, Benigni A, Zoja C. ADAMTS13 Deficiency Shortens the Life Span of Mice With Experimental Diabetes. Diabetes 2018; 67:2069-2083. [PMID: 29976618 DOI: 10.2337/db17-1508] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Accepted: 06/18/2018] [Indexed: 11/13/2022]
Abstract
In patients with diabetes, impaired activity of ADAMTS13 (a disintegrin and metalloprotease with thrombospondin type 1 repeats, member 13), the plasma metalloprotease that cleaves highly thrombogenic von Willebrand factor multimers, is a major risk factor of cardiovascular events. Here, using Adamts13-/- mice made diabetic by streptozotocin, we investigated the impact of the lack of ADAMTS13 on the development of diabetes-associated end-organ complications. Adamts13-/- mice experienced a shorter life span than their diabetic wild-type littermates. It was surprising that animal death was not related to the occurrence of detectable thrombotic events. The lack of ADAMTS13 drastically increased the propensity for ventricular arrhythmias during dobutamine-induced stress in diabetic mice. Cardiomyocytes of diabetic Adamts13-/- mice exhibited an aberrant distribution of the ventricular gap junction connexin 43 and increased phosphorylation of Ca2+/calmodulin-dependent kinase II (CaMKII), and with the consequent CaMKII-induced disturbance in Ca2+ handling, which underlie propensity for arrhythmia. In vitro, thrombospondin 1 (TSP1) promoted, in a paracrine manner, CaMKII phosphorylation in murine HL-1 cardiomyocytes, and ADAMTS13 acted to inhibit TSP1-induced CaMKII activation. In conclusion, the deficiency of ADAMTS13 may underlie the onset of lethal arrhythmias in diabetes through increased CaMKII phosphorylation in cardiomyocytes. Our findings disclose a novel function for ADAMTS13 beyond its antithrombotic activity.
Collapse
Affiliation(s)
- Paola Cassis
- IRCCS - Istituto di Ricerche Farmacologiche Mario Negri, Centro Anna Maria Astori, Science and Technology Park Kilometro Rosso, Bergamo, Italy
| | - Domenico Cerullo
- IRCCS - Istituto di Ricerche Farmacologiche Mario Negri, Centro Anna Maria Astori, Science and Technology Park Kilometro Rosso, Bergamo, Italy
| | - Cristina Zanchi
- IRCCS - Istituto di Ricerche Farmacologiche Mario Negri, Centro Anna Maria Astori, Science and Technology Park Kilometro Rosso, Bergamo, Italy
| | - Daniela Corna
- IRCCS - Istituto di Ricerche Farmacologiche Mario Negri, Centro Anna Maria Astori, Science and Technology Park Kilometro Rosso, Bergamo, Italy
| | - Vincenzo Lionetti
- Institute of Life Sciences, Scuola Superiore Sant'Anna, Pisa, Italy
- UOS Anesthesia and Intensive Care, Fondazione Toscana "G. Monasterio," Pisa, Italy
| | - Fabrizio Giordano
- IRCCS - Istituto di Ricerche Farmacologiche Mario Negri, Centro Anna Maria Astori, Science and Technology Park Kilometro Rosso, Bergamo, Italy
| | - Rubina Novelli
- IRCCS - Istituto di Ricerche Farmacologiche Mario Negri, Centro Anna Maria Astori, Science and Technology Park Kilometro Rosso, Bergamo, Italy
| | - Sara Conti
- IRCCS - Istituto di Ricerche Farmacologiche Mario Negri, Centro Anna Maria Astori, Science and Technology Park Kilometro Rosso, Bergamo, Italy
| | | | - Marco Matteucci
- Institute of Life Sciences, Scuola Superiore Sant'Anna, Pisa, Italy
| | - Monica Locatelli
- IRCCS - Istituto di Ricerche Farmacologiche Mario Negri, Centro Anna Maria Astori, Science and Technology Park Kilometro Rosso, Bergamo, Italy
| | - Giulia Taraboletti
- IRCCS - Istituto di Ricerche Farmacologiche Mario Negri, Centro Anna Maria Astori, Science and Technology Park Kilometro Rosso, Bergamo, Italy
| | - Sebastian Villa
- IRCCS - Istituto di Ricerche Farmacologiche Mario Negri, Centro Anna Maria Astori, Science and Technology Park Kilometro Rosso, Bergamo, Italy
| | - Sara Gastoldi
- IRCCS - Istituto di Ricerche Farmacologiche Mario Negri, Centro Anna Maria Astori, Science and Technology Park Kilometro Rosso, Bergamo, Italy
| | - Giuseppe Remuzzi
- IRCCS - Istituto di Ricerche Farmacologiche Mario Negri, Centro Anna Maria Astori, Science and Technology Park Kilometro Rosso, Bergamo, Italy
- Unit of Nephrology and Dialysis, Azienda Socio-Sanitaria Territoriale (ASST), Papa Giovanni XXIII, Bergamo, Italy
- "L. Sacco" Department of Biomedical and Clinical Sciences, University of Milan, Milan, Italy
| | - Ariela Benigni
- IRCCS - Istituto di Ricerche Farmacologiche Mario Negri, Centro Anna Maria Astori, Science and Technology Park Kilometro Rosso, Bergamo, Italy
| | - Carlamaria Zoja
- IRCCS - Istituto di Ricerche Farmacologiche Mario Negri, Centro Anna Maria Astori, Science and Technology Park Kilometro Rosso, Bergamo, Italy
| |
Collapse
|
5
|
Abstract
Objective: Atrial fibrillation (AF) is the most common rapid cardiac arrhythmia associated with high morbidity and mortality. Stimulation of the sympathetic nerve is involved in AF occurrence. The gap junction protein connexin 43 (Cx43) plays a key role in electrical conduction velocity in cardiac tissues, and under expression of Cx43 was linked with AF. The aim of this study was to investigate whether Cx43 was involved in sympathetic AF. Methods: Fifteen dogs were randomly divided into 3 groups (5 in each group). Sympathetic AF was induced in dogs and isolated canine atrial myocytes by isoproterenol (ISO) perfusion and rapid atrium pacing (RAP). The expression levels of nerve growth factor (NGF) and tyrosine hydroxylase (TH) in the atrial tissues were detected using immunohistochemical staining. The transcription and protein expression of Cx43 in the AF cell model was measured. Subsequently, Cx43 was blocked by short interfering (si) RNA in atrial myocytes and the gap junctional inter-cellular communication was detected using the scrape-loading and dye transfer assay. Results: Sympathetic AF was successfully induced by a combination of ISO perfusion and RAP. The expression levels of NGF and TH were increased in the RAP group, and further increased in the RAP + ISO group. Tissue samples from the AF dogs had a lower Cx43 level than those of the control group (p<0.05). The expressions of mRNA and protein of Cx43 in sympathetic AF cell model decreased by 26% and 28%, respectively, when compared with the control group, with p<0.05. Silencing Cx43 in cells by siRNA could also efficiently reduce Cx43 expression. The relative levels of Cx45 mRNA were decreased by 73% compared with unaffected cells. The scrape-loading and dye transfer assay showed that gap junctional intercellular communication was hampered in the sympathetic AF cell model and silencing Cx43 could impede channel conduction. Conclusion: The results suggested that low expression of Cx43 was involved in sympathetic AF by influencing intercellular channel conduction. Intervention of Cx43 expression might be an appealing therapy to sympathetic AF.
Collapse
|
6
|
De Mello WC. Cell-to-cell diffusion of glucose in the mammalian heart is disrupted by high glucose. Implications for the diabetic heart. Exp Cell Res 2015; 334:239-45. [DOI: 10.1016/j.yexcr.2015.01.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Revised: 01/29/2015] [Accepted: 01/31/2015] [Indexed: 11/29/2022]
|
7
|
Grippo AJ, Moffitt JA, Henry MK, Firkins R, Senkler J, McNeal N, Wardwell J, Scotti MAL, Dotson A, Schultz R. Altered Connexin 43 and Connexin 45 protein expression in the heart as a function of social and environmental stress in the prairie vole. Stress 2015; 18:107-14. [PMID: 25338193 PMCID: PMC4675659 DOI: 10.3109/10253890.2014.979785] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Exposure to social and environmental stressors may influence behavior as well as autonomic and cardiovascular regulation, potentially leading to depressive disorders and cardiac dysfunction including elevated sympathetic drive, reduced parasympathetic function, and ventricular arrhythmias. The cellular mechanisms that underlie these interactions are not well understood. One mechanism may involve alterations in the expression of Connexin43 (Cx43) and Connexin45 (Cx45), gap junction proteins in the heart that play an important role in ensuring efficient cell-to-cell coupling and the maintenance of cardiac rhythmicity. The present study investigated the hypothesis that long-term social isolation, combined with mild environmental stressors, would produce both depressive behaviors and altered Cx43 and Cx45 expression in the left ventricle of prairie voles - a socially monogamous rodent model. Adult, female prairie voles were exposed to either social isolation (n = 22) or control (paired, n = 23) conditions (4 weeks), alone or in combination with chronic mild stress (CMS) (1 week). Social isolation, versus paired control conditions, produced significantly (p < 0.05) increased depressive behaviors in a 5-min forced swim test, and CMS exacerbated (p < 0.05) these behaviors. Social isolation (alone) reduced (p < 0.05) total Cx43 expression in the left ventricle; whereas CMS (but not isolation) increased (p < 0.05) total Cx45 expression and reduced (p < 0.05) the Cx43/Cx45 ratio, measured via Western blot analysis. The present findings provide insight into potential cellular mechanisms underlying altered cardiac rhythmicity associated with social and environmental stress in the prairie vole.
Collapse
Affiliation(s)
- Angela J. Grippo
- Department of Psychology, Northern Illinois University, DeKalb, IL
| | - Julia A. Moffitt
- Department of Physiology and Pharmacology, Des Moines University, Des Moines, IA
- Department of Kinesiology, St. Ambrose University, Davenport, IA
| | - Matthew K. Henry
- Department of Physiology and Pharmacology, Des Moines University, Des Moines, IA
| | - Rachel Firkins
- Department of Physiology and Pharmacology, Des Moines University, Des Moines, IA
| | - Jonathan Senkler
- Department of Physiology and Pharmacology, Des Moines University, Des Moines, IA
| | - Neal McNeal
- Department of Psychology, Northern Illinois University, DeKalb, IL
| | - Joshua Wardwell
- Department of Psychology, Northern Illinois University, DeKalb, IL
| | - Melissa-Ann L. Scotti
- Department of Psychology, Northern Illinois University, DeKalb, IL
- Department of Psychiatry and Brain-Body Center, University of Illinois at Chicago, Chicago, IL
| | - Ashley Dotson
- Department of Psychology, Northern Illinois University, DeKalb, IL
| | - Rachel Schultz
- Department of Psychology, Northern Illinois University, DeKalb, IL
| |
Collapse
|
8
|
Moffitt JA, Henry MK, Welliver KC, Jepson AJ, Garnett ER. Hindlimb unloading results in increased predisposition to cardiac arrhythmias and alters left ventricular connexin 43 expression. Am J Physiol Regul Integr Comp Physiol 2013; 304:R362-73. [PMID: 23302960 DOI: 10.1152/ajpregu.00391.2012] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Hindlimb unloading (HU) is a well-established animal model of cardiovascular deconditioning. Previous data indicate that HU results in cardiac sympathovagal imbalance. It is well established that cardiac sympathovagal imbalance increases the risk for developing cardiac arrhythmias. The cardiac gap junction protein connexin 43 (Cx43) is predominately expressed in the left ventricle (LV) and ensures efficient cell-to-cell electrical coupling. In the current study we wanted to test the hypothesis that HU would result in increased predisposition to cardiac arrhythmias and alter the expression and/or phosphorylation of LV-Cx43. Electrocardiographic data using implantable telemetry were obtained over a 10- to 14-day HU or casted control (CC) condition and in response to a sympathetic stressor using isoproterenol administration and brief restraint. The arrhythmic burden was calculated using a modified scoring system to quantify spontaneous and provoked arrhythmias. In addition, Western blot analysis was used to measure LV-Cx43 expression in lysates probed with antibodies directed against the total and an unphosphorylated form of Cx43 in CC and HU rats. HU resulted in a significantly greater total arrhythmic burden during the sympathetic stressor with significantly more ventricular arrhythmias occurring. In addition, there was increased expression of total LV-Cx43 observed with no difference in the expression of unphosphorylated LV-Cx43. Specifically, the increased expression of LV-Cx43 was consistent with the phosphorylated form. These data taken together indicate that cardiovascular deconditioning produced through HU results in increased predisposition to cardiac arrhythmias and increased expression of phosphorylated LV-Cx43.
Collapse
Affiliation(s)
- Julia A Moffitt
- Department of Physiology and Pharmacology, Des Moines University, 3200 Grand Ave., Des Moines, IA 50312, USA.
| | | | | | | | | |
Collapse
|
9
|
Hawat G, Hélie P, Baroudi G. Single intravenous low-dose injections of connexin 43 mimetic peptides protect ischemic heart in vivo against myocardial infarction. J Mol Cell Cardiol 2012; 53:559-66. [DOI: 10.1016/j.yjmcc.2012.07.008] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2012] [Revised: 07/18/2012] [Accepted: 07/18/2012] [Indexed: 02/05/2023]
|
10
|
Ratiometric imaging of calcium during ischemia-reperfusion injury in isolated mouse hearts using Fura-2. Biomed Eng Online 2012; 11:39. [PMID: 22812644 PMCID: PMC3466138 DOI: 10.1186/1475-925x-11-39] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2011] [Accepted: 06/28/2012] [Indexed: 12/31/2022] Open
Abstract
Background We present an easily implementable method for measuring Fura-2 fluorescence from isolated mouse hearts using a commercially available switching light source and CCD camera. After calibration, it provides a good estimate of intracellular [Ca2+] with both high spatial and temporal resolutions, permitting study of changes in dispersion of diastolic [Ca2+], Ca2+ transient dynamics, and conduction velocities in mouse hearts. In a proof-of-principle study, we imaged isolated Langendorff-perfused mouse hearts with reversible regional myocardial infarctions. Methods Isolated mouse hearts were perfused in the Landendorff-mode and loaded with Fura-2. Hearts were then paced rapidly and subjected to 15 minutes of regional ischemia by ligation of the left anterior descending coronary artery, following which the ligation was removed to allow reperfusion for 15 minutes. Fura-2 fluorescence was recorded at regular intervals using a high-speed CCD camera. The two wavelengths of excitation light were interleaved at a rate of 1 KHz with a computer controlled switching light source to illuminate the heart. Results Fura-2 produced consistent Ca2+ transients from different hearts. Ligating the coronary artery rapidly generated a well defined region with a dramatic rise in diastolic Ca2+ without a significant change in transient amplitude; Ca2+ handling normalized during reperfusion. Conduction velocity was reduced by around 50% during ischemia, and did not recover significantly when monitored for 15 minutes following reperfusion. Conclusions Our method of imaging Fura-2 from isolated whole hearts is capable of detecting pathological changes in intracellular Ca2+ levels in cardiac tissue. The persistent change in the conduction velocities indicates that changes to tissue connectivity rather than altered intracellular Ca2+ handling may be underlying the electrical instabilities commonly seen in patients following a myocardial infarction.
Collapse
|
11
|
Ferreira JCB, Mochly-Rosen D, Boutjdir M. Regulation of cardiac excitability by protein kinase C isozymes. Front Biosci (Schol Ed) 2012. [PMID: 22202075 DOI: 10.2741/283] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Cardiac excitability and electrical activity are determined by the sum of individual ion channels, gap junctions and exchanger activities. Electrophysiological remodeling during heart disease involves changes in membrane properties of cardiomyocytes and is related to higher prevalence of arrhythmia-associated morbidity and mortality. Pharmacological and genetic manipulation of cardiac cells as well as animal models of cardiovascular diseases are used to identity changes in electrophysiological properties and the molecular mechanisms associated with the disease. Protein kinase C (PKC) and several other kinases play a pivotal role in cardiac electrophysiological remodeling. Therefore, identifying specific therapies that regulate these kinases is the main focus of current research. PKC, a family of serine/threonine kinases, has been implicated as potential signaling nodes associated with biochemical and biophysical stress in cardiovascular diseases. In this review, we describe the role of PKC isozymes that are involved in cardiac excitability and discuss both genetic and pharmacological tools that were used, their attributes and limitations. Selective and effective pharmacological interventions to normalize cardiac electrical activities and correct cardiac arrhythmias will be of great clinical benefit.
Collapse
|
12
|
Tang Y, Wang M, Le X, Meng J, Huang L, Yu P, Chen J, Wu P. Antioxidant and cardioprotective effects of Danshensu (3-(3, 4-dihydroxyphenyl)-2-hydroxy-propanoic acid from Salvia miltiorrhiza) on isoproterenol-induced myocardial hypertrophy in rats. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2011; 18:1024-1030. [PMID: 21665454 DOI: 10.1016/j.phymed.2011.05.007] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2010] [Revised: 02/23/2011] [Accepted: 05/04/2011] [Indexed: 05/30/2023]
Abstract
Myocardial hypertrophy has been linked to the development of a variety of cardiovascular diseases, and is a risk factor for myocardial ischemia, arrhythmias, and sudden cardiac death. The objective of the present study was to evaluate the cardioprotective effects of Danshensu (DSS), a water-soluble active component of Danshen, on cardiac hypertrophy in rats. We are the first to report that DSS reversed Cx43 down-regulation in ventricular tissue. Cardiomyopathy in rats was produced using isoproterenol (Iso) treatment (2.5 mg/kg/d, s.c.) for seven days. DSS (3 and 10 mg/kg/d, i.p.) and Valsartan (Val) (10 mg/kg, i.g.) were administered on days 4-7 of Iso-treatment. Heart weight index, hemodynamic parameters, and ECG II parameters were monitored and recorded; protein expression of left ventricular connexin 43 (Cx43) and the activity of the redox system were assayed, and arrhythmias were produced using a coronary ligation/reperfusion procedure. The results demonstrated that DSS treatment significantly decreased heart weight/body weight (HW/BW) and left ventricular weight/body weight (LVW/BW) ratios. The protective role of DSS against Iso-induced myocardial hypertrophy was further confirmed using ECG. The incidences of ventricular tachycardia and ventricular fibrillation (VT, VF) and arrhythmic scores were higher in the model group and were suppressed by DSS. DSS decreased the serum and myocardium levels of creatine kinase, lactate dehydrogenase, and malondialdehyde (CK, LDH, and MDA) and increased serum activity of superoxide dismutase (SOD) in a dose-dependent manner. Cx43 expression in the left ventricle was down-regulated, and there was significant oxidative stress in this model of cardiomyopathy. DSS reversed the down-regulated Cx43 protein levels and showed potent anti-oxidative activities and cellular protection. These data demonstrate that DSS can prevent cardiac I/R injury and improve cardiac function in a rat model of hypertrophy, the effects partially resulting from antioxidants and the protection from Cx43 expression.
Collapse
Affiliation(s)
- Yiqun Tang
- Research Division of Pharmacology, China Pharmaceutical University, No. 24 Tongjia Lane, Nanjing, 210009, China.
| | | | | | | | | | | | | | | |
Collapse
|
13
|
Zografos T, Katritsis DG. Inhibition of the renin-angiotensin system for prevention of atrial fibrillation. Pacing Clin Electrophysiol 2011; 33:1270-85. [PMID: 20636314 DOI: 10.1111/j.1540-8159.2010.02832.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Atrial fibrillation (AF) is a source of considerable morbidity and mortality. There has been compelling evidence supporting the role of renin-angiotensin system (RAS) in the genesis and perpetuation of AF through atrial remodeling, and experimental studies have validated the utilization of RAS inhibition for AF prevention. This article reviews clinical trials on the use of angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) for the prevention of AF. Results have been variable, depending on the clinical background of treated patients. ACEIs and ARBs appear beneficial for primary prevention of AF in patients with heart failure, whereas they are not equally effective in hypertensive patients with normal left ventricular function. Furthermore, the use of ACEIs or ARBs for secondary prevention of AF has been found beneficial only after electrical cardioversion. Additional data are needed to establish the potential clinical role of renin-angiotensin inhibition for prevention of AF.
Collapse
Affiliation(s)
- Theodoros Zografos
- Department of Cardiology, Athens Euroclinic, 9 Athanassiadou Street, Athens, Greece
| | | |
Collapse
|