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Mazzella AJ, Kouri A, O'Quinn MP, Royal SH, Syed FF. Improvement in left ventricular ejection fraction after radiofrequency catheter ablation of premature atrial contractions in a 23-year-old man. HeartRhythm Case Rep 2019; 5:524-527. [PMID: 31700798 PMCID: PMC6831766 DOI: 10.1016/j.hrcr.2019.08.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Affiliation(s)
- Anthony J Mazzella
- Division of Cardiology, University of North Carolina Hospitals, Chapel Hill, North Carolina
| | - Ana Kouri
- University of North Carolina School of Medicine, Chapel Hill, North Carolina
| | - Michael P O'Quinn
- Division of Cardiology, University of North Carolina Hospitals, Chapel Hill, North Carolina
| | - Stephen H Royal
- Division of Cardiology, University of North Carolina Hospitals, Chapel Hill, North Carolina
| | - Faisal F Syed
- Division of Cardiology, University of North Carolina Hospitals, Chapel Hill, North Carolina
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O'Quinn MP, Dormer KJ, Huizar JF, Nguyen KT, Kaszala K, Sima A, Ellenbogen KA, Tan AY. Epicardial injection of nanoformulated calcium into cardiac ganglionic plexi suppresses autonomic nerve activity and postoperative atrial fibrillation. Heart Rhythm 2019; 16:597-605. [PMID: 30929671 PMCID: PMC6446939 DOI: 10.1016/j.hrthm.2018.10.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Indexed: 12/12/2022]
Abstract
BACKGROUND Imbalanced activation of the cardiac autonomic nervous system triggers postoperative atrial fibrillation (POAF). Neuronal calcium overload induces apoptosis. We hypothesize that epicardial injection of timed-release nanoformulated CaCl2 (nCaCl2) into left atrial ganglionic plexi (GP) modulates autonomic function and suppresses POAF. OBJECTIVE The purpose of this study was to determine whether nCaCl2 GP therapy suppresses POAF. METHODS We used a novel canine model of POAF with implanted radiotelemetry to record nerve activity (NA) from the left stellate ganglion (SNA), left cardiac vagus nerve, and GP. At week 3, nCaCl2 (n = 7) or vehicle control (sham; n = 3) was injected into left pulmonary vein GP (LGP), followed by right pulmonary vein GP at week 4. Atrial effective refractory period (AERP) and atrial fibrillation vulnerability (AFV) were assessed in vivo. Resting and exercise NA and heart rate (HR) were assessed before and after LGP treatment. RESULTS AERP decreased (P < .0001) and AFV increased (P = .008) at week 3 vs baseline. However, nCaCl2-LGP treatment reversed these changes and restored them to baseline after 1 week (P = .04). Subsequent nCaCl2-right pulmonary vein GP treatment further reduced AFV (P = .03). In contrast, AFV increased (P = .001) and AERP remained decreased (P = .01) 1 week after sham-LGP treatment vs baseline. nCaCl2-LGP treatment reduced NA from GP (P < .02) and NA from the left cardiac vagus nerve (P < .05) and increased SNA (P < .02). Despite increased SNA, HR was decreased (P < .01) with loss of HR-SNA correlation (R = 0.62). After sham-LGP treatment, NA was unchanged and HR-SNA remained correlated (R = 0.95). Histology confirmed nCaCl2-GP colocalization, apoptosis, and loss of immunoreactivity in nCaCl2-treated somas. CONCLUSION Epicardial injection of nCaCl2 into left atrial GP induced neuroapoptosis and modulated autonomic function. This reversed a postoperative reduction in AERP and suppressed POAF.
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Affiliation(s)
- Michael P O'Quinn
- Electrophysiology Section, Division of Cardiology, Hunter Holmes McGuire VAMC, Richmond, Virginia; Pauley Heart Center, Virginia Commonwealth University Medical Center, Richmond, Virginia
| | - Kenneth J Dormer
- Liberty University College of Osteopathic Medicine, Lynchburg, Virginia
| | - Jose F Huizar
- Electrophysiology Section, Division of Cardiology, Hunter Holmes McGuire VAMC, Richmond, Virginia; Pauley Heart Center, Virginia Commonwealth University Medical Center, Richmond, Virginia
| | | | - Karoly Kaszala
- Electrophysiology Section, Division of Cardiology, Hunter Holmes McGuire VAMC, Richmond, Virginia; Pauley Heart Center, Virginia Commonwealth University Medical Center, Richmond, Virginia
| | - Adam Sima
- Department of Biostatistics, Virginia Commonwealth University Medical Center, Richmond, Virginia
| | - Kenneth A Ellenbogen
- Electrophysiology Section, Division of Cardiology, Hunter Holmes McGuire VAMC, Richmond, Virginia
| | - Alex Y Tan
- Electrophysiology Section, Division of Cardiology, Hunter Holmes McGuire VAMC, Richmond, Virginia; Pauley Heart Center, Virginia Commonwealth University Medical Center, Richmond, Virginia.
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Del Buono MG, O'Quinn MP, Garcia P, Gerszten E, Roberts C, Moeller FG, Abbate A. Cardiac arrest due to ventricular fibrillation in a 23-year-old woman with broken heart syndrome. Cardiovasc Pathol 2017; 30:78-81. [PMID: 28802178 DOI: 10.1016/j.carpath.2017.06.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 06/24/2017] [Accepted: 06/26/2017] [Indexed: 11/16/2022] Open
Abstract
Broken heart syndrome, also known as takotsubo cardiomyopathy, is a syndrome characterized by a transient regional systolic dysfunction of the left ventricle associated to a psychological stress. We herein describe a case of a 23-year-old female habitual marijuana user who was resuscitated after cardiac arrest and then diagnosed with midventricular stress cardiomyopathy complicated by subendocardial hemorrhage. We discuss this unique pathological finding, the incidence of arrhythmias in this syndrome, and the possible relation with chronic cannabis and tobacco use. Unfortunately, the patient did not survive, but had she survived, the management of the patient for secondary prevention would have been challenging considering the risk of recurrence with this disease.
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Affiliation(s)
- Marco Giuseppe Del Buono
- VCU Pauley Heart Center, Virginia Commonwealth University, Richmond, VA, USA; Campus Bio-Medico University, Rome, Italy
| | - Michael P O'Quinn
- VCU Pauley Heart Center, Virginia Commonwealth University, Richmond, VA, USA
| | - Paulo Garcia
- Department of Pathology, Virginia Commonwealth University, Richmond, VA, USA
| | - Enrique Gerszten
- Department of Pathology, Virginia Commonwealth University, Richmond, VA, USA
| | - Charlotte Roberts
- VCU Pauley Heart Center, Virginia Commonwealth University, Richmond, VA, USA
| | - F Gerald Moeller
- Institute of Drug and Alcohol Studies, Virginia Commonwealth University, Richmond, VA, USA
| | - Antonio Abbate
- VCU Pauley Heart Center, Virginia Commonwealth University, Richmond, VA, USA.
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Ongstad EL, O'Quinn MP, Ghatnekar GS, Yost MJ, Gourdie RG. A Connexin43 Mimetic Peptide Promotes Regenerative Healing and Improves Mechanical Properties in Skin and Heart. Adv Wound Care (New Rochelle) 2013; 2:55-62. [PMID: 24527326 DOI: 10.1089/wound.2011.0341] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2011] [Indexed: 01/26/2023] Open
Abstract
SIGNIFICANCE Evidence is building that the gap junction protein connexin43 (Cx43) is an important molecule in regenerative healing of skin and heart. Excess scarring from skin wound healing is a continuing clinical problem. Humans generally lack the ability to regenerate tissue following injury, and some degree of fibrotic repair occurs. In the skin, this results in unsightly scars with inferior mechanical properties. In the heart, scarring causes disruption in the contractility of cardiac muscle and increases the risk of deadly arrhythmia. Therapies that tip the balance of wound healing away from scar tissue and toward regeneration would thus represent a significant medical advance. RECENT ADVANCES A cell-permeant peptide, αCT1 (alpha connexin carboxyl-terminal peptide), based on the carboxyl-terminus of connexin43, has been shown to elicit changes in gap junction organization and intracellular communication. In the skin, αCT1 applied at acute time points results in decreased inflammatory response, reduced area of scar progenitor tissue, and restoration of more normal dermal structure and mechanical strength. αCT1 application to infarcted hearts improved cardiac contractility, reduced the propensity for arrhythmia, and increased conduction velocity through the injured heart. CRITICAL ISSUES Application of therapies like αCT1 could reduce cutaneous scarring and improve mechanical properties of healed skin and the contractile function and electrical stability of the heart following injury or surgery. FUTURE DIRECTIONS αCT1 is a potential therapy for cutaneous wounds that could lead to reduced scarring and improvements in the mechanical properties of healed skin. For injured myocardial tissues, this Cx43 mimetic peptide may also provide a therapeutic approach for targeting pathological fibrosis and reducing the likelihood of sudden death from cardiac arrhythmias.
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Affiliation(s)
- Emily L Ongstad
- Department of Bioengineering, Clemson University , Clemson, South Carolina
| | - Michael P O'Quinn
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina , Charleston, South Carolina
| | | | - Michael J Yost
- Department of Surgery, Medical University of South Carolina , Charleston, South Carolina
| | - Robert G Gourdie
- Department of Bioengineering, Clemson University , Clemson, South Carolina. ; Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina , Charleston, South Carolina
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Strungs EG, Ongstad EL, O'Quinn MP, Palatinus JA, Jourdan LJ, Gourdie RG. Cryoinjury models of the adult and neonatal mouse heart for studies of scarring and regeneration. Methods Mol Biol 2013; 1037:343-53. [PMID: 24029946 DOI: 10.1007/978-1-62703-505-7_20] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
A major limitation in studies of the injured heart is animal-to-animal variability in wound size resulting from commonly used techniques such as left anterior descending coronary artery ligation. This variability can make standard errors sufficiently large that mean separation between treatment and control groups can be difficult without replicating numbers (n) of animals in groups by excessive amounts. Here, we describe the materials and protocol necessary for delivering a standardized non-transmural cryoinjury to the left ventricle of an adult mouse heart that may in part obviate the issue of injury variance between animals. As reported previously, this cryoinjury model generates a necrotic wound to the ventricle of consistent size and shape that resolves into a scar of uniform size, shape, and organization. The cryo-model also provides an extended injury border zone that exhibits classic markers of remodeling found in surviving cardiac tissue at the edge of a myocardial infarction, including connexin43 (Cx43) lateralization. In a further extension of the method, we describe how we have adapted the model to deliver a cryoinjury to the apex of the heart of neonatal mice-a modification that may be useful for studies of myocardial regeneration in mammals.
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Affiliation(s)
- Erik G Strungs
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC, USA
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Rémond MC, Iaffaldano G, O'Quinn MP, Mezentseva NV, Garcia V, Harris BS, Gourdie RG, Eisenberg CA, Eisenberg LM. GATA6 reporter gene reveals myocardial phenotypic heterogeneity that is related to variations in gap junction coupling. Am J Physiol Heart Circ Physiol 2011; 301:H1952-64. [PMID: 21908788 DOI: 10.1152/ajpheart.00635.2011] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This study examined transgenic mice whose expression of a β-galactosidase (lacZ) reporter is driven by a GATA6 gene enhancer. Previous investigations established that transcription of the transgene was associated with precardiac mesoderm and primary heart tube myocardium, which decreased progressively, so that its expression was no longer observed within ventricular myocardium by midgestation. Expression of this reporter in the adult was investigated for insights into myocyte homeostasis and cardiovascular biology. Morphometric analysis determined that <1% of myocytes, often found in small clusters, express this GATA6-associated reporter in the adult heart. LacZ expression was also found in the ascending aorta. Myocardial expression of the transgene was not associated with a proliferative phenotype or new myocyte formation, as lacZ-positive myocytes neither labeled with cell division markers nor following 5-bromodeoxyuridine pulse-chase experimentation. Despite exhibiting normal adherens junctions, these myocytes appeared to exhibit decreased connexin 43 gap junctions. Treatment with the gap junctional blocker heptanol both in vivo and in culture elevated myocardial β-galactosidase activity, suggesting that deficient gap junctional communication underlies expression of the transgenic reporter. LacZ expression within the myocardium was also enhanced in response to cryoinjury and isoproterenol-induced hypertrophy. These results reveal a previously uncharacterized phenotypic heterogeneity in the myocardium and suggest that decreased gap junctional coupling leads to induction of a signaling pathway that utilizes a unique GATA6 enhancer. Upregulation of lacZ reporter gene expression following cardiac injury indicates this transgenic mouse may serve as a model for examining the transition of the heart from healthy to pathological states.
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Affiliation(s)
- Mathieu C Rémond
- New York Medical College/Westchester Medical Center Stem Cell Laboratory, Department of Physiology, New York Medical College, Valhalla, NY, USA
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O'Quinn MP, Palatinus JA, Harris BS, Hewett KW, Gourdie RG. A peptide mimetic of the connexin43 carboxyl terminus reduces gap junction remodeling and induced arrhythmia following ventricular injury. Circ Res 2011; 108:704-15. [PMID: 21273554 DOI: 10.1161/circresaha.110.235747] [Citation(s) in RCA: 122] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
RATIONALE Remodeling of connexin (Cx)43 gap junctions (GJs) is linked to ventricular arrhythmia. OBJECTIVES A peptide mimetic of the carboxyl terminal (CT) of Cx43, incorporating a postsynaptic density-95/disks-large/ZO-1 (PDZ)-binding domain, reduces Cx43/ZO-1 interaction and GJ size remodeling in vitro. Here, we determined: (1) whether the Cx43-CT mimetic αCT1 altered GJ remodeling following left ventricular (LV) injury in vivo; (2) whether αCT1 affected arrhythmic propensity; and (3) the mechanism of αCT1 effects on arrhythmogenicity and GJ remodeling. METHODS AND RESULTS A cryoinjury model generating a reproducible wound and injury border zone (IBZ) in the LV was used. Adherent methylcellulose patches formulated to locally release αCT1 (< 48 hours) were placed on cryoinjuries. Relative to controls, Cx43/ZO-1 colocalization in the IBZ was reduced by αCT1 by 24 hours after injury. Programmed electric stimulation ex vivo and optical mapping of voltage transients indicated that peptide-treated hearts showed reduced inducible arrhythmias and increased ventricular depolarization rates 7 to 9 days after injury. At 24 hours and 1 week after injury, αCT1-treated hearts maintained Cx43 in intercalated disks (IDs) in the IBZ, whereas by 1 week after injury, controls demonstrated Cx43 remodeling from IDs to lateralized distributions. Over a postinjury time course of 1 week, αCT1-treated IBZs showed increased Cx43 phosphorylation at serine368 (Cx43-pS368) relative to control tissues. In biochemical assays, αCT1 promoted phosphorylation of serine368 by protein kinase (PK)C-ε in a dose-dependent manner that was modulated by, but did not require ZO-1 PDZ2. CONCLUSIONS αCT1 increases Cx43-pS368 in vitro in a PKC-ε-dependent manner and in the IBZ in vivo acutely following ventricular injury. αCT1-mediated increase in Cx43-pS368 phosphorylation may contribute to reductions in inducible-arrhythmia following injury.
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Affiliation(s)
- Michael P O'Quinn
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, USA
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Palatinus JA, O'Quinn MP, Barker RJ, Harris BS, Jourdan J, Gourdie RG. ZO-1 determines adherens and gap junction localization at intercalated disks. Am J Physiol Heart Circ Physiol 2010; 300:H583-94. [PMID: 21131473 DOI: 10.1152/ajpheart.00999.2010] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The disruption of the spatial order of electromechanical junctions at myocyte-intercalated disks (ICDs) is a poorly understood characteristic of many cardiac disease states. Here, in vitro and in vivo evidence is provided that zonula occludens-1 (ZO-1) regulates the organization of gap junctions (GJs) and adherens junctions (AJs) at ICDs. We investigated the contribution of ZO-1 to cell-cell junction localization by expressing a dominant-negative ZO-1 construct (DN-ZO-1) in rat ventricular myocytes (VMs). The expression of DN-ZO-1 in cultured neonatal VMs for 72 h reduced the interaction of ZO-1 and N-cadherin, as assayed by colocalization and coimmunoprecipitation, prompting cytoplasmic internalization of AJ and GJ proteins. DN-ZO-1 expression in adult VMs in vivo also reduced N-cadherin colocalization with ZO-1, a phenomenon not observed when the connexin-43 (Cx43)-ZO-1 interaction was disrupted using a mimetic of the ZO-1-binding ligand from Cx43. DN-ZO-1-infected VMs demonstrated large GJs at the ICD periphery and showed a loss of focal ZO-1 concentrations along plaque edges facing the disk interior. Additionally, there was breakdown of the characteristic ICD pattern of small interior and large peripheral GJs. Continuous DN-ZO-1 expression in VMs over postnatal development reduced ICD-associated Cx43 GJs and increased lateralized and cytoplasmic Cx43. We conclude that ZO-1 regulation of GJ localization is via an association with the N-cadherin multiprotein complex and that this is a key determinant of stable localization of both AJs and GJs at the ICD.
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Affiliation(s)
- Joseph A Palatinus
- Department of Regenerative Medicine and Cell Biology, Cardiovascular Biology Center, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC, 29425, USA
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Ghatnekar GS, O'Quinn MP, Jourdan LJ, Gurjarpadhye AA, Draughn RL, Gourdie RG. Connexin43 carboxyl-terminal peptides reduce scar progenitor and promote regenerative healing following skin wounding. Regen Med 2009; 4:205-23. [PMID: 19317641 DOI: 10.2217/17460751.4.2.205] [Citation(s) in RCA: 109] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
AIM Gap-junctional connexin43 (Cx43) has roles in multiple aspects of skin wound healing - including scarring. The aim here was to study the effects of a cell-permeant peptide from the Cx43 carboxyl-terminus (CT) on scarring and regeneration following cutaneous injury. MATERIALS & METHODS The effects of Cx43 CT peptide were studied in mouse and pig models of cutaneous injury. The parameters assessed included neutrophil density, wound closure, granulation, regeneration and skin tensile properties. RESULTS Cx43 CT-peptide prompted decreases in area of scar progenitor tissue and promoted restoration of dermal histoarchitecture and mechanical strength following wounding of skin. These changes in healing were preceded by peptide-induced reduction in inflammatory neutrophil infiltration and alterations in the organization of epidermal Cx43, including increased connexon aggregation. CONCLUSION Cx43 CT peptide promotes regenerative healing of cutaneous wounds and may have applications in tissues other than skin, including heart, cornea and spinal cord.
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Affiliation(s)
- Gautam S Ghatnekar
- Comparative Medicine, Medical University of South Carolina, Charleston, SC, USA
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