1
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Gómez-Viquez NL, Balderas-Villalobos J, Bello-Sánchez MD, Mayorga-Luna M, Mailloux-Salinas P, García-Castañeda M, Ríos-Pérez EB, Mártinez-Ávila MA, Camacho-Castillo LDC, Bravo G, Ávila G, Altamirano J, Carvajal K. Oxidative stress in early metabolic syndrome impairs cardiac RyR2 and SERCA2a activity and modifies the interplay of these proteins during Ca 2+ waves. Arch Physiol Biochem 2023; 129:1058-1070. [PMID: 33689540 DOI: 10.1080/13813455.2021.1895224] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Accepted: 02/19/2021] [Indexed: 10/21/2022]
Abstract
We investigated how oxidative stress (OS) alters Ca2+ handling in ventricular myocytes in early metabolic syndrome (MetS) in sucrose-fed rats. The effects of N-acetyl cysteine (NAC) or dl-Dithiothreitol (DTT) on systolic Ca2+ transients (SCaTs), diastolic Ca2+ sparks (CaS) and Ca2+ waves (CaW), recorded by confocal techniques, and L-type Ca2+ current (ICa), assessed by whole-cell patch clamp, were evaluated in MetS and Control cells. MetS myocytes exhibited decreased SCaTs and CaS frequency but unaffected CaW propagation. In Control cells, NAC/DTT reduced RyR2/SERCA2a activity blunting SCaTs, CaS frequency and CaW propagation, suggesting that basal ROS optimised Ca2+ signalling by maintaining RyR2/SERCA2a function and that these proteins facilitate CaW propagation. Conversely, NAC/DTT in MetS recovered RyR2/SERCA2a function, improving SCaTs and CaS frequency, but unexpectedly decreasing CaW propagation. We hypothesised that OS decreases RyR2/SERCA2a activity at early MetS, and while decreased SERCA2a favours CaW propagation, diminished RyR2 restrains it.
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Affiliation(s)
- Norma Leticia Gómez-Viquez
- Departamento de Farmacobiología, Centro de Investigación y de Estudios Avanzados-Instituto Politécnico Nacional, Ciudad de México, México
| | - Jaime Balderas-Villalobos
- Departamento de Farmacobiología, Centro de Investigación y de Estudios Avanzados-Instituto Politécnico Nacional, Ciudad de México, México
- Laboratorio de Nutrición Experimental, Instituto Nacional de Pediatría, Ciudad de México, México
| | - Ma Dolores Bello-Sánchez
- Departamento de Farmacobiología, Centro de Investigación y de Estudios Avanzados-Instituto Politécnico Nacional, Ciudad de México, México
| | - Maritza Mayorga-Luna
- Departamento de Farmacobiología, Centro de Investigación y de Estudios Avanzados-Instituto Politécnico Nacional, Ciudad de México, México
| | - Patrick Mailloux-Salinas
- Departamento de Farmacobiología, Centro de Investigación y de Estudios Avanzados-Instituto Politécnico Nacional, Ciudad de México, México
| | - Maricela García-Castañeda
- Departamento de Bioquímica, Centro de Investigación y de Estudios Avanzados-Instituto Politécnico Nacional, Ciudad de México, México
| | - Erick Benjamín Ríos-Pérez
- Departamento de Bioquímica, Centro de Investigación y de Estudios Avanzados-Instituto Politécnico Nacional, Ciudad de México, México
| | | | | | - Guadalupe Bravo
- Departamento de Farmacobiología, Centro de Investigación y de Estudios Avanzados-Instituto Politécnico Nacional, Ciudad de México, México
| | - Guillermo Ávila
- Departamento de Bioquímica, Centro de Investigación y de Estudios Avanzados-Instituto Politécnico Nacional, Ciudad de México, México
| | - Julio Altamirano
- Tecnologico de Monterrey, Escuela de Medicina y Ciencias de la Salud, Monterrey, México
| | - Karla Carvajal
- Laboratorio de Nutrición Experimental, Instituto Nacional de Pediatría, Ciudad de México, México
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2
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Kaplan A, Lakkis B, El-Samadi L, Karaayvaz EB, Booz GW, Zouein FA. Cooling Down Inflammation in the Cardiovascular System via the Nicotinic Acetylcholine Receptor. J Cardiovasc Pharmacol 2023; 82:241-265. [PMID: 37539950 DOI: 10.1097/fjc.0000000000001455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Accepted: 07/06/2023] [Indexed: 08/05/2023]
Abstract
ABSTRACT Inflammation is a major player in many cardiovascular diseases including hypertension, atherosclerosis, myocardial infarction, and heart failure. In many individuals, these conditions coexist and mutually exacerbate each other's progression. The pathophysiology of these diseases entails the active involvement of both innate and adaptive immune cells. Immune cells that possess the α7 subunit of the nicotinic acetylcholine receptor on their surface have the potential to be targeted through both pharmacological and electrical stimulation of the cholinergic system. The cholinergic system regulates the inflammatory response to various stressors in different organ systems by systematically suppressing spleen-derived monocytes and chemokines and locally improving immune cell function. Research on the cardiovascular system has demonstrated the potential for atheroma plaque stabilization and regression as favorable outcomes. Smaller infarct size and reduced fibrosis have been associated with improved cardiac function and a decrease in adverse cardiac remodeling. Furthermore, enhanced electrical stability of the myocardium can lead to a reduction in the incidence of ventricular tachyarrhythmia. In addition, improving mitochondrial dysfunction and decreasing oxidative stress can result in less myocardial tissue damage caused by reperfusion injury. Restoring baroreflex activity and reduction in renal damage can promote blood pressure regulation and help counteract hypertension. Thus, the present review highlights the potential of nicotinic acetylcholine receptor activation as a natural approach to alleviate the adverse consequences of inflammation in the cardiovascular system.
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Affiliation(s)
- Abdullah Kaplan
- Department of Pharmacology and Toxicology, Faculty of Medicine, American University of Beirut, Riad El-Solh, Beirut, Lebanon
- Department of Cardiology, Kemer Public Hospital, Kemer, Antalya, Turkey
- The Cardiovascular, Renal, and Metabolic Diseases Research Center of Excellence, American University of Beirut Medical Center, Riad El-Solh, Beirut, Lebanon
| | - Bachir Lakkis
- Department of Pharmacology and Toxicology, Faculty of Medicine, American University of Beirut, Riad El-Solh, Beirut, Lebanon
| | - Lana El-Samadi
- Department of Pharmacology and Toxicology, Faculty of Medicine, American University of Beirut, Riad El-Solh, Beirut, Lebanon
| | - Ekrem Bilal Karaayvaz
- Department of Cardiology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - George W Booz
- Department of Pharmacology and Toxicology, School of Medicine, University of Mississippi Medical Center, Jackson, MS; and
| | - Fouad A Zouein
- Department of Pharmacology and Toxicology, Faculty of Medicine, American University of Beirut, Riad El-Solh, Beirut, Lebanon
- The Cardiovascular, Renal, and Metabolic Diseases Research Center of Excellence, American University of Beirut Medical Center, Riad El-Solh, Beirut, Lebanon
- Department of Pharmacology and Toxicology, School of Medicine, University of Mississippi Medical Center, Jackson, MS; and
- Department of Signaling and Cardiovascular Pathophysiology, UMR-S 1180, Inserm, Université Paris-Saclay, France
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3
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SULFORAPHANE EFFECTS ON CARDIAC FUNCTION AND CALCIUM-HANDLING RELATED PROTEINS IN TWO EXPERIMENTAL MODELS OF HEART DISEASE. J Cardiovasc Pharmacol 2021; 79:325-334. [DOI: 10.1097/fjc.0000000000001191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Accepted: 11/20/2021] [Indexed: 11/26/2022]
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4
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Angelini M, Pezhouman A, Savalli N, Chang MG, Steccanella F, Scranton K, Calmettes G, Ottolia M, Pantazis A, Karagueuzian HS, Weiss JN, Olcese R. Suppression of ventricular arrhythmias by targeting late L-type Ca2+ current. J Gen Physiol 2021; 153:212725. [PMID: 34698805 PMCID: PMC8552156 DOI: 10.1085/jgp.202012584] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 07/15/2021] [Accepted: 09/02/2021] [Indexed: 12/15/2022] Open
Abstract
Ventricular arrhythmias, a leading cause of sudden cardiac death, can be triggered by cardiomyocyte early afterdepolarizations (EADs). EADs can result from an abnormal late activation of L-type Ca2+ channels (LTCCs). Current LTCC blockers (class IV antiarrhythmics), while effective at suppressing EADs, block both early and late components of ICa,L, compromising inotropy. However, computational studies have recently demonstrated that selective reduction of late ICa,L (Ca2+ influx during late phases of the action potential) is sufficient to potently suppress EADs, suggesting that effective antiarrhythmic action can be achieved without blocking the early peak ICa,L, which is essential for proper excitation–contraction coupling. We tested this new strategy using a purine analogue, roscovitine, which reduces late ICa,L with minimal effect on peak current. Scaling our investigation from a human CaV1.2 channel clone to rabbit ventricular myocytes and rat and rabbit perfused hearts, we demonstrate that (1) roscovitine selectively reduces ICa,L noninactivating component in a human CaV1.2 channel clone and in ventricular myocytes native current, (2) the pharmacological reduction of late ICa,L suppresses EADs and EATs (early after Ca2+ transients) induced by oxidative stress and hypokalemia in isolated myocytes, largely preserving cell shortening and normal Ca2+ transient, and (3) late ICa,L reduction prevents/suppresses ventricular tachycardia/fibrillation in ex vivo rabbit and rat hearts subjected to hypokalemia and/or oxidative stress. These results support the value of an antiarrhythmic strategy based on the selective reduction of late ICa,L to suppress EAD-mediated arrhythmias. Antiarrhythmic therapies based on this idea would modify the gating properties of CaV1.2 channels rather than blocking their pore, largely preserving contractility.
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Affiliation(s)
- Marina Angelini
- Division of Molecular Medicine, Department of Anesthesiology & Perioperative Medicine, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA
| | - Arash Pezhouman
- Department of Medicine (Cardiology), David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA
| | - Nicoletta Savalli
- Division of Molecular Medicine, Department of Anesthesiology & Perioperative Medicine, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA
| | - Marvin G Chang
- Department of Anesthesia and Critical Care, Massachusetts General Hospital, Harvard Medical School, Boston, MA
| | - Federica Steccanella
- Division of Molecular Medicine, Department of Anesthesiology & Perioperative Medicine, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA
| | - Kyle Scranton
- Division of Molecular Medicine, Department of Anesthesiology & Perioperative Medicine, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA
| | - Guillaume Calmettes
- Department of Medicine (Cardiology), David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA
| | - Michela Ottolia
- Division of Molecular Medicine, Department of Anesthesiology & Perioperative Medicine, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA.,University of California, Los Angeles Cardiovascular Theme, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA
| | - Antonios Pantazis
- Division of Neurobiology, Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden.,Wallenberg Center for Molecular Medicine, Linköping University, Linköping, Sweden
| | - Hrayr S Karagueuzian
- Department of Medicine (Cardiology), David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA.,Cardiovascular Research Laboratories, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA
| | - James N Weiss
- Department of Medicine (Cardiology), David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA.,Cardiovascular Research Laboratories, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA.,Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA
| | - Riccardo Olcese
- Division of Molecular Medicine, Department of Anesthesiology & Perioperative Medicine, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA.,Cardiovascular Research Laboratories, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA.,University of California, Los Angeles Cardiovascular Theme, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA.,Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA
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5
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Xu D, Murakoshi N, Tajiri K, Duo F, Okabe Y, Murakata Y, Yuan Z, Li S, Aonuma K, Song Z, Shimoda Y, Mori H, Sato A, Nogami A, Aonuma K, Ieda M. Xanthine oxidase inhibitor febuxostat reduces atrial fibrillation susceptibility by inhibition of oxidized CaMKII in Dahl salt-sensitive rats. Clin Sci (Lond) 2021; 135:2409-2422. [PMID: 34386810 DOI: 10.1042/cs20210405] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 08/06/2021] [Accepted: 08/13/2021] [Indexed: 11/17/2022]
Abstract
Oxidative stress could be a possible mechanism and a therapeutic target of atrial fibrillation (AF). However, the effects of the xanthine oxidase (XO) inhibition for AF remain to be fully elucidated. We investigated the effects of a novel XO inhibitor febuxostat on AF compared with allopurinol in hypertension rat model. Five-week-old Dahl salt-sensitive rats were fed either low-salt (LS) (0.3% NaCl) or high-salt (HS) (8% NaCl) diet. After 4 weeks of diet, HS diet rats were divided into three groups: orally administered to vehicle (HS-C), febuxostat (5 mg/kg/day) (HS-F), or allopurinol (50 mg/kg/day) (HS-A). After 4 weeks of treatment, systolic blood pressure (SBP) was significantly higher in HS-C than LS, and it was slightly but significantly decreased by treatment with each XO inhibitor. AF duration was significantly prolonged in HS-C compared with LS, and significantly suppressed in both HS-F and HS-A (LS; 5.8 ± 3.5 s, HS-C; 33.9 ± 23.7 s, HS-F; 15.0 ± 14.1 s, HS-A; 20.1 ± 11.9 s: P<0.05). Ca2+ spark frequency was obviously increased in HS-C rats and reduced in the XO inhibitor-treated rats, especially in HS-F group. Western blotting revealed that the atrial expression levels of Met281/282-oxidized Ca2+/Calmodulin-dependent kinase II (CaMKII) and Ser2814-phosphorylated ryanodine receptor 2 were significantly increased in HS-C, and those were suppressed in HS-F and HS-A. Decreased expression of gap junction protein connexin 40 in HS-C was partially restored by treatment with each XO inhibitor. In conclusion, XO inhibitor febuxostat, as well as allopurinol, could reduce hypertension-related increase in AF perpetuation by restoring Ca2+ handling and gap junction.
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Affiliation(s)
- DongZhu Xu
- Department of Cardiology, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Nobuyuki Murakoshi
- Department of Cardiology, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Kazuko Tajiri
- Department of Cardiology, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Feng Duo
- Department of Cardiology, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Yuta Okabe
- Department of Cardiology, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Yoshiko Murakata
- Department of Cardiology, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Zixun Yuan
- Department of Cardiology, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Siqi Li
- Department of Cardiology, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Kazuhiro Aonuma
- Department of Cardiology, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Zonghu Song
- Department of Cardiology, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Yuzuno Shimoda
- Department of Cardiology, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Haruka Mori
- Department of Cardiology, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Akira Sato
- Department of Cardiology, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Akihiko Nogami
- Department of Cardiology, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Kazutaka Aonuma
- Department of Cardiology, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Masaki Ieda
- Department of Cardiology, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan
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6
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Cabral EV, Vieira LD, Sant'Helena BRM, Ribeiro VS, Farias JS, Aires RS, Paz ST, Muzi‐Filho H, Paixão AD, Vieyra A. Alpha‐Tocopherol during lactation and after weaning alters the programming effect of prenatal high salt intake on cardiac and renal functions of adult male offspring. Clin Exp Pharmacol Physiol 2019; 46:1151-1165. [DOI: 10.1111/1440-1681.13161] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 08/06/2019] [Accepted: 08/08/2019] [Indexed: 12/27/2022]
Affiliation(s)
- Edjair V. Cabral
- Department of Physiology and Pharmacology Federal University of Pernambuco Recife Brazil
- National Center of Structural Biology and Bioimaging/CENABIO Federal University of Rio de Janeiro Rio de Janeiro Brazil
| | - Leucio D. Vieira
- Department of Physiology and Pharmacology Federal University of Pernambuco Recife Brazil
- National Center of Structural Biology and Bioimaging/CENABIO Federal University of Rio de Janeiro Rio de Janeiro Brazil
| | | | - Valdilene S. Ribeiro
- Department of Physiology and Pharmacology Federal University of Pernambuco Recife Brazil
| | - Juliane S. Farias
- Department of Physiology and Pharmacology Federal University of Pernambuco Recife Brazil
| | - Regina S. Aires
- Department of Physiology and Pharmacology Federal University of Pernambuco Recife Brazil
| | - Silvania T. Paz
- Department of Pathology Federal University of Pernambuco Recife Brazil
| | - Humberto Muzi‐Filho
- National Center of Structural Biology and Bioimaging/CENABIO Federal University of Rio de Janeiro Rio de Janeiro Brazil
- Carlos Chagas Filho Institute of Biophysics Federal University of Rio de Janeiro Rio de Janeiro Brazil
- National Institute of Science and Technology for Regenerative Medicine/REGENERA Rio de Janeiro Brazil
| | - Ana D. Paixão
- Department of Physiology and Pharmacology Federal University of Pernambuco Recife Brazil
- National Center of Structural Biology and Bioimaging/CENABIO Federal University of Rio de Janeiro Rio de Janeiro Brazil
| | - Adalberto Vieyra
- National Center of Structural Biology and Bioimaging/CENABIO Federal University of Rio de Janeiro Rio de Janeiro Brazil
- Carlos Chagas Filho Institute of Biophysics Federal University of Rio de Janeiro Rio de Janeiro Brazil
- National Institute of Science and Technology for Regenerative Medicine/REGENERA Rio de Janeiro Brazil
- Graduate Program in Translational Biomedicine/BIOTRANS Grande Rio University Duque de Caxias Brazil
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7
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Szarka N, Pabbidi MR, Amrein K, Czeiter E, Berta G, Pohoczky K, Helyes Z, Ungvari Z, Koller A, Buki A, Toth P. Traumatic Brain Injury Impairs Myogenic Constriction of Cerebral Arteries: Role of Mitochondria-Derived H 2O 2 and TRPV4-Dependent Activation of BK ca Channels. J Neurotrauma 2018; 35:930-939. [PMID: 29179622 DOI: 10.1089/neu.2017.5056] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Traumatic brain injury (TBI) impairs autoregulation of cerebral blood flow, which contributes to the development of secondary brain injury, increasing mortality of patients. Impairment of pressure-induced myogenic constriction of cerebral arteries plays a critical role in autoregulatory dysfunction; however, the underlying cellular and molecular mechanisms are not well understood. To determine the role of mitochondria-derived H2O2 and large-conductance calcium-activated potassium channels (BKCa) in myogenic autoregulatory dysfunction, middle cerebral arteries (MCAs) were isolated from rats with severe weight drop-impact acceleration brain injury. We found that 24 h post-TBI MCAs exhibited impaired myogenic constriction, which was restored by treatment with a mitochondria-targeted antioxidant (mitoTEMPO), by scavenging of H2O2 (polyethylene glycol [PEG]-catalase) and by blocking both BKCa channels (paxilline) and transient receptor potential cation channel subfamily V member 4 (TRPV4) channels (HC 067047). Further, exogenous administration of H2O2 elicited significant dilation of MCAs, which was inhibited by blocking either BKCa or TRPV4 channels. Vasodilation induced by the TRPV4 agonist GSK1016790A was inhibited by paxilline. In cultured vascular smooth muscle cells H2O2 activated BKCa currents, which were inhibited by blockade of TRPV4 channels. Collectively, our results suggest that after TBI, excessive mitochondria-derived H2O2 activates BKCa channels via a TRPV4-dependent pathway in the vascular smooth muscle cells, which impairs pressure-induced constriction of cerebral arteries. Future studies should elucidate the therapeutic potential of pharmacological targeting of this pathway in TBI, to restore autoregulatory function in order to prevent secondary brain damage and decrease mortality.
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Affiliation(s)
- Nikolett Szarka
- Cerebrovascular Laboratory, Department of Neurosurgery, Medical School University of Pecs, Pecs. Hungary.,Neurotrauma Research Group, Janos Szentagothai Research Center, Medical School University of Pecs, Pecs. Hungary.,Department of Translational Medicine, Medical School University of Pecs, Pecs. Hungary
| | - Mallikarjuna R Pabbidi
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
| | - Krisztina Amrein
- Cerebrovascular Laboratory, Department of Neurosurgery, Medical School University of Pecs, Pecs. Hungary.,Neurotrauma Research Group, Janos Szentagothai Research Center, Medical School University of Pecs, Pecs. Hungary
| | - Endre Czeiter
- Cerebrovascular Laboratory, Department of Neurosurgery, Medical School University of Pecs, Pecs. Hungary.,Neurotrauma Research Group, Janos Szentagothai Research Center, Medical School University of Pecs, Pecs. Hungary.,MTA-PTE Clinical Neuroscience MR Research Group, Pecs, Hungary
| | - Gergely Berta
- Department of Medical Biology, Medical School University of Pecs, Pecs. Hungary
| | - Krisztina Pohoczky
- Department of Pharmacology and Pharmacotherapy, Medical School University of Pecs, Pecs. Hungary.,MTA-PTE NAP B Chronic Pain Research Group, Pecs, Hungary
| | - Zsuzsanna Helyes
- Department of Pharmacology and Pharmacotherapy, Medical School University of Pecs, Pecs. Hungary.,MTA-PTE NAP B Chronic Pain Research Group, Pecs, Hungary
| | - Zoltan Ungvari
- Reynolds Oklahoma Center on Aging, Donald W. Reynolds Department of Geriatric Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
| | - Akos Koller
- Cerebrovascular Laboratory, Department of Neurosurgery, Medical School University of Pecs, Pecs. Hungary.,Institute of Natural Sciences, University of Physical Education, Budapest, Hungary.,Department of Physiology, New York Medical College, Valhalla, New York
| | - Andras Buki
- Cerebrovascular Laboratory, Department of Neurosurgery, Medical School University of Pecs, Pecs. Hungary.,Neurotrauma Research Group, Janos Szentagothai Research Center, Medical School University of Pecs, Pecs. Hungary
| | - Peter Toth
- Cerebrovascular Laboratory, Department of Neurosurgery, Medical School University of Pecs, Pecs. Hungary.,Neurotrauma Research Group, Janos Szentagothai Research Center, Medical School University of Pecs, Pecs. Hungary.,Department of Translational Medicine, Medical School University of Pecs, Pecs. Hungary.,MTA-PTE Clinical Neuroscience MR Research Group, Pecs, Hungary.,Reynolds Oklahoma Center on Aging, Donald W. Reynolds Department of Geriatric Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
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8
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The reduced myofilament responsiveness to calcium contributes to the negative force-frequency relationship in rat cardiomyocytes: role of reactive oxygen species and p-38 map kinase. Pflugers Arch 2017; 469:1663-1673. [DOI: 10.1007/s00424-017-2058-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Accepted: 08/11/2017] [Indexed: 01/01/2023]
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9
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Mesenchymal stem cells suppress cardiac alternans by activation of PI3K mediated nitroso-redox pathway. J Mol Cell Cardiol 2016; 98:138-45. [PMID: 27238412 DOI: 10.1016/j.yjmcc.2016.05.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Revised: 05/03/2016] [Accepted: 05/25/2016] [Indexed: 01/06/2023]
Abstract
BACKGROUND The paracrine action of non-cardiac progenitor cells is robust, but not well understood. Mesenchymal stem cells (MSC) have been shown to enhance calcium (Ca(++)) cycling in myocytes. Therefore, we hypothesized that MSCs can suppress cardiac alternans, an important arrhythmia substrate, by paracrine action on Ca(++) cycling. METHODS AND RESULTS Human cardiac myocyte monolayers derived from iPS cells (hCM) were cultured without or with human MSCs (hMSC) directly or plated on a transwell insert. Ca(++) transient alternans (Ca(++) ALT) and Ca(++) transient duration (CaD) were measured from hCM monolayers following application of 200μM H2O2. Ca(++) ALT in hCM was significantly decreased when cultured with hMSCs directly (97%, p<0.0001) and when cultured with hMSC in the transwell insert (80%, p<0.0001). When hCM with hMSCs were pretreated with PI3K or eNOS inhibitors, Ca(++) ALT was larger than baseline by 20% (p<0.0001) and 36% (p<0.0001), respectively. In contrast, Ca(++) ALT was reduced by 89% compared to baseline (p<0.0001) when hCM monolayers without hMSCs were pretreated with 20μM GSNO. In all experiments, changes in Ca(++) ALT were mirrored by changes in CaD. Finally, real time quantitative PCR revealed no significant differences in mRNA expression of RyR2, SERCA2a, and phospholamban between hCM cultured with or without hMSCs. CONCLUSION Ca(++) ALT is suppressed by hMSCs in a paracrine fashion due to activation of a PI3K-mediated nitroso-redox pathway. These findings demonstrate, for the first time, how stem cell therapy might be antiarrhythmic by suppressing cardiac alternans through paracrine action on Ca(++) cycling.
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10
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Bonetto JHP, Fernandes RO, Seolin BGDL, Müller DD, Teixeira RB, Araujo AS, Vassallo D, Schenkel PC, Belló-Klein A. Sulforaphane improves oxidative status without attenuating the inflammatory response or cardiac impairment induced by ischemia–reperfusion in rats. Can J Physiol Pharmacol 2016; 94:508-16. [DOI: 10.1139/cjpp-2015-0282] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Sulforaphane, a natural isothiocyanate, demonstrates cardioprotection associated with its capacity to stimulate endogenous antioxidants and to inhibit inflammation. The aim of this study was to investigate whether sulforaphane is capable of attenuating oxidative stress and inflammatory responses through the TLR4/MyD88/NFκB pathway, and thereby could modulate post-ischemic ventricular function in isolated rat hearts submitted to ischemia and reperfusion. Male Wistar rats received sulforaphane (10 mg·kg−1·day−1) or vehicle i.p. for 3 days. Global ischemia was performed using isolated hearts, 24 h after the last injection, by interruption of the perfusion flow. The protocol included a 20 min pre-ischemic period followed by 20 min of ischemia and a 20 min reperfusion. Although no changes in mechanical function were observed, sulforaphane induced a significant increase in superoxide dismutase and heme oxygenase-1 expression (both 66%) and significantly reduced reactive oxygen species levels (7%). No differences were observed for catalase and glutathione peroxidase expression or their activities, nor for thioredoxin reductase, glutaredoxin reductase and glutathione-S-transferase. No differences were found in lipid peroxidation or TLR4, MyD88, and NF-κB expression. In conclusion, although sulforaphane was able to stimulate endogenous antioxidants modestly, this result did not impact inflammatory signaling or cardiac function of hearts submitted to ischemia and reperfusion.
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Affiliation(s)
- Jéssica Hellen Poletto Bonetto
- Laboratory of Cardiovascular Physiology, Institute of Basic Health Science (ICBS), Federal University of Rio Grande do Sul (UFRGS), Rio Grande do Sul, Brazil
| | - Rafael Oliveira Fernandes
- Laboratory of Cardiovascular Physiology, Institute of Basic Health Science (ICBS), Federal University of Rio Grande do Sul (UFRGS), Rio Grande do Sul, Brazil
| | - Bruna Gazzi de Lima Seolin
- Laboratory of Cardiovascular Physiology, Institute of Basic Health Science (ICBS), Federal University of Rio Grande do Sul (UFRGS), Rio Grande do Sul, Brazil
| | - Dalvana Daneliza Müller
- Laboratory of Cardiovascular Physiology, Institute of Basic Health Science (ICBS), Federal University of Rio Grande do Sul (UFRGS), Rio Grande do Sul, Brazil
| | - Rayane Brinck Teixeira
- Laboratory of Cardiovascular Physiology, Institute of Basic Health Science (ICBS), Federal University of Rio Grande do Sul (UFRGS), Rio Grande do Sul, Brazil
| | - Alex Sander Araujo
- Laboratory of Cardiovascular Physiology, Institute of Basic Health Science (ICBS), Federal University of Rio Grande do Sul (UFRGS), Rio Grande do Sul, Brazil
| | - Dalton Vassallo
- Health Science Center of Vitória (EMESCAM), Espírito Santo, Brazil
| | - Paulo Cavalheiro Schenkel
- Laboratory of Cardiovascular Physiology, Institute of Basic Health Science (ICBS), Federal University of Rio Grande do Sul (UFRGS), Rio Grande do Sul, Brazil
| | - Adriane Belló-Klein
- Laboratory of Cardiovascular Physiology, Institute of Basic Health Science (ICBS), Federal University of Rio Grande do Sul (UFRGS), Rio Grande do Sul, Brazil
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11
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Kiselyov K, Muallem S. ROS and intracellular ion channels. Cell Calcium 2016; 60:108-14. [PMID: 26995054 DOI: 10.1016/j.ceca.2016.03.004] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Revised: 03/03/2016] [Accepted: 03/04/2016] [Indexed: 12/15/2022]
Abstract
Oxidative stress is a well-known driver of numerous pathological processes involving protein and lipid peroxidation and DNA damage. The resulting increase of pro-apoptotic pressure drives tissue damage in a host of conditions, including ischemic stroke and reperfusion injury, diabetes, death in acute pancreatitis and neurodegenerative diseases. Somewhat less frequently discussed, but arguably as important, is the signaling function of oxidative stress stemming from the ability of oxidative stress to modulate ion channel activity. The evidence for the modulation of the intracellular ion channels and transporters by oxidative stress is constantly emerging and such evidence suggests new regulatory and pathological circuits that can be explored towards new treatments for diseases in which oxidative stress is an issue. In this review we summarize the current knowledge on the effects of oxidative stress on the intracellular ion channels and transporters and their role in cell function.
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Affiliation(s)
- Kirill Kiselyov
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, United States; Epithelial Signaling and Transport Section, Molecular Physiology and Therapeutics Branch NIH, NIDCR, Bethesda, MD 20892, United States.
| | - Shmuel Muallem
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, United States; Epithelial Signaling and Transport Section, Molecular Physiology and Therapeutics Branch NIH, NIDCR, Bethesda, MD 20892, United States.
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12
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Odnoshivkina UG, Sytchev VI, Nurullin LF, Giniatullin AR, Zefirov AL, Petrov AM. β2-adrenoceptor agonist-evoked reactive oxygen species generation in mouse atria: implication in delayed inotropic effect. Eur J Pharmacol 2015; 765:140-53. [PMID: 26297975 DOI: 10.1016/j.ejphar.2015.08.020] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Revised: 08/05/2015] [Accepted: 08/17/2015] [Indexed: 12/20/2022]
Abstract
Fenoterol, a β2-adrenoceptor agonist, has anti-apoptotic action in cardiomyocytes and induces a specific pattern of downstream signaling. We have previously reported that exposure to fenoterol (5 μM) results in a delayed positive inotropic effect which is related to changes in both Ca2+ transient and NO. Here, the changes in reactive oxygen species (ROS) production in response to the fenoterol administration and the involvement of ROS in effect of this agonist on contractility were investigated in mouse isolated atria. Stimulation of β2-adrenoceptor increases a level of extracellular ROS, while intracellular ROS level rises only after removal of fenoterol from the bath. NADPH-oxidase inhibitor (apocynin) prevents the increase in ROS production and the Nox2 isoform is immunofluorescently colocalized with β2-adrenoceptor at the atrial myocytes. Treatments with antioxidants (N-acetyl-L-cysteine, NADPH inhibitors, exogenous catalases) significantly inhibit the fenoterol induced increase in the contraction amplitude, probably by attenuating Ca2+ transient and up-regulating NO production. ROS generated in a β2-adrenoceptor-dependent manner can potentiate the activity of some Ca2+ channels. Indeed, inhibition of ryanodine receptors, TRPV-or L-type Ca2+- channels shows a similar efficacy in reduction of positive inotropic effect of both fenoterol and H2O2. In addition, detection of mitochondrial ROS indicates that fenoterol triggers a slow increase in ROS which is prevented by rotenone, but rotenone has no impact on the inotropic effect of fenoterol. We suggest that stimulation of β2-adrenoceptor with fenoterol causes the activation of NADPH-oxidase and after the agonist removal extracellularly generated ROS penetrates into the cell, increasing the atrial contractions probably via Ca2+ channels.
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Affiliation(s)
- Ulia G Odnoshivkina
- Department of Normal Physiology, Kazan State Medical University, Butlerova st., 49, Kazan 420012, Russia
| | - Vaycheslav I Sytchev
- Department of Normal Physiology, Kazan State Medical University, Butlerova st., 49, Kazan 420012, Russia
| | - Leniz F Nurullin
- Kazan Institute of Biochemistry and Biophysics, Kazan Scientific Center of Russian Academy of Sciences, Laboratory of Biophysics of Synaptic Processes, Lobatchevsky str. 2/31, P.O. 30, Kazan 420111, Russia
| | - Arthur R Giniatullin
- Department of Normal Physiology, Kazan State Medical University, Butlerova st., 49, Kazan 420012, Russia
| | - Andrei L Zefirov
- Department of Normal Physiology, Kazan State Medical University, Butlerova st., 49, Kazan 420012, Russia
| | - Alexey M Petrov
- Department of Normal Physiology, Kazan State Medical University, Butlerova st., 49, Kazan 420012, Russia.
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Oxidation of ryanodine receptor (RyR) and calmodulin enhance Ca release and pathologically alter, RyR structure and calmodulin affinity. J Mol Cell Cardiol 2015; 85:240-8. [PMID: 26092277 DOI: 10.1016/j.yjmcc.2015.06.009] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2015] [Revised: 05/12/2015] [Accepted: 06/12/2015] [Indexed: 11/21/2022]
Abstract
Oxidative stress may contribute to cardiac ryanodine receptor (RyR2) dysfunction in heart failure (HF) and arrhythmias. Altered RyR2 domain-domain interaction (domain unzipping) and calmodulin (CaM) binding affinity are allosterically coupled indices of RyR2 conformation. In HF RyR2 exhibits reduced CaM binding, increased domain unzipping and greater SR Ca leak, and dantrolene can reverse these changes. However, effects of oxidative stress on RyR2 conformation and leak in myocytes are poorly understood. We used fluorescent CaM, FKBP12.6, and domain-peptide biosensor (F-DPc10) to measure, directly in cardiac myocytes, (1) RyR2 activation by hydrogen peroxide (H2O2)-induced oxidation, (2) RyR2 conformation change caused by oxidation, (3) CaM-RyR2 and FK506-binding protein (FKBP12.6)-RyR2 interaction upon oxidation, and (4) whether dantrolene affects 1-3. H2O2 was used to mimic oxidative stress. H2O2 significantly increased the frequency of Ca(2+) sparks and spontaneous Ca(2+) waves, and dantrolene almost completely blocked these effects. H2O2 pretreatment significantly reduced CaM-RyR2 binding, but had no effect on FKBP12.6-RyR2 binding. Dantrolene restored CaM-RyR2 binding but had no effect on intracellular and RyR2 oxidation levels. H2O2 also accelerated F-DPc10-RyR2 association while dantrolene slowed it. Thus, H2O2 causes conformational changes (sensed by CaM and DPc10 binding) associated with Ca leak, and dantrolene reverses these RyR2 effects. In conclusion, in cardiomyocytes, H2O2 treatment markedly reduces the CaM-RyR2 affinity, has no effect on FKBP12.6-RyR2 affinity, and causes domain unzipping. Dantrolene can correct domain unzipping, restore CaM-RyR2 affinity, and quiet pathological RyR2 channel gating. F-DPc10 and CaM are useful biosensors of a pathophysiological RyR2 state.
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Plummer BN, Liu H, Wan X, Deschênes I, Laurita KR. Targeted antioxidant treatment decreases cardiac alternans associated with chronic myocardial infarction. Circ Arrhythm Electrophysiol 2014; 8:165-73. [PMID: 25491741 DOI: 10.1161/circep.114.001789] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
BACKGROUND In myocardial infarction (MI), repolarization alternans is a potent arrhythmia substrate that has been linked to Ca2+ cycling proteins, such as sarcoplasmic reticulum Ca2+ ATPase (SERCA2a), located in the sarcoplasmic reticulum. MI is also associated with oxidative stress and increased xanthine oxidase (XO) activity, an important source of reactive oxygen species (ROS) in the sarcoplasmic reticulum that may reduce SERCA2a function. We hypothesize that in chronic MI, XO-mediated oxidation of SERCA2a is a mechanism of cardiac alternans. METHODS AND RESULTS Male Lewis rats underwent ligation of the left anterior descending coronary artery (n=54) or sham procedure (n=24). At 4 weeks, optical mapping of intracellular Ca2+ and ROS was performed. ECG T-wave alternans (ECG ALT) and Ca2+ transient alternans (Ca2+ALT) were induced by rapid pacing (300-120 ms) before and after the XO inhibitor allopurinol (ALLO, 50 µmol/L). In MI, ECG ALT (2.32±0.41%) and Ca2+ ALT (22.3±4.5%) were significantly greater compared with sham (0.18±0.08%, P<0.001; 0.79±0.32%, P<0.01). Additionally, ROS was increased by 137% (P<0.01) and oxidation of SERCA2a by 30% (P<0.05) in MI compared with sham. Treatment with ALLO significantly decreased ECG ALT (-77±9%, P<0.05) and Ca2+ ALT (-56±7%, P<0.05) and, importantly, reduced ROS (-65%, P<0.01) and oxidation of SERCA2a (-38%, P<0.05). CaMKII inhibition and general antioxidant treatment had no effect on ECG ALT and Ca2+ ALT. CONCLUSIONS These results demonstrate, for the first time, that in MI, increased ROS from XO is a significant cause of repolarization alternans. This suggests that targeting XO ROS production may be effective at preventing arrhythmia substrates in chronic MI.
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Affiliation(s)
- Bradley N Plummer
- From The Heart and Vascular Research Center, Department of Medicine, MetroHealth Campus (B.N.P., H.L., X.W., I.D., K.R.L.), and Department of Biomedical Engineering (B.N.P., I.D., K.R.L.), Case Western Reserve University, Cleveland, OH
| | - Haiyan Liu
- From The Heart and Vascular Research Center, Department of Medicine, MetroHealth Campus (B.N.P., H.L., X.W., I.D., K.R.L.), and Department of Biomedical Engineering (B.N.P., I.D., K.R.L.), Case Western Reserve University, Cleveland, OH
| | - Xiaoping Wan
- From The Heart and Vascular Research Center, Department of Medicine, MetroHealth Campus (B.N.P., H.L., X.W., I.D., K.R.L.), and Department of Biomedical Engineering (B.N.P., I.D., K.R.L.), Case Western Reserve University, Cleveland, OH
| | - Isabelle Deschênes
- From The Heart and Vascular Research Center, Department of Medicine, MetroHealth Campus (B.N.P., H.L., X.W., I.D., K.R.L.), and Department of Biomedical Engineering (B.N.P., I.D., K.R.L.), Case Western Reserve University, Cleveland, OH
| | - Kenneth R Laurita
- From The Heart and Vascular Research Center, Department of Medicine, MetroHealth Campus (B.N.P., H.L., X.W., I.D., K.R.L.), and Department of Biomedical Engineering (B.N.P., I.D., K.R.L.), Case Western Reserve University, Cleveland, OH.
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Ziolo MT, Houser SR. Abnormal Ca(2+) cycling in failing ventricular myocytes: role of NOS1-mediated nitroso-redox balance. Antioxid Redox Signal 2014; 21:2044-59. [PMID: 24801117 PMCID: PMC4208612 DOI: 10.1089/ars.2014.5873] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
SIGNIFICANCE Heart failure (HF) results from poor heart function and is the leading cause of death in Western society. Abnormalities of Ca(2+) handling at the level of the ventricular myocyte are largely responsible for much of the poor heart function. RECENT ADVANCES Although studies have unraveled numerous mechanisms for the abnormal Ca(2+) handling, investigations over the past decade have indicated that much of the contractile dysfunction and adverse remodeling that occurs in HF involves oxidative stress. CRITICAL ISSUES Regrettably, antioxidant therapy has been an immense disappointment in clinical trials. Thus, redox signaling is being reassessed to elucidate why antioxidants failed to treat HF. FUTURE DIRECTIONS A recently identified aspect of redox signaling (specifically the superoxide anion radical) is its interaction with nitric oxide, known as the nitroso-redox balance. There is a large nitroso-redox imbalance with HF, and we suggest that correcting this imbalance may be able to restore myocyte contraction and improve heart function.
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Affiliation(s)
- Mark T Ziolo
- 1 Department of Physiology and Cell Biology, Davis Heart and Lung Research Institute, The Ohio State University , Columbus, Ohio
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Longstanding complex regional pain syndrome is associated with activating autoantibodies against alpha-1a adrenoceptors. Pain 2014; 155:2408-17. [DOI: 10.1016/j.pain.2014.09.022] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Revised: 09/09/2014] [Accepted: 09/16/2014] [Indexed: 11/22/2022]
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Greensmith DJ, Galli GLJ, Trafford AW, Eisner DA. Direct measurements of SR free Ca reveal the mechanism underlying the transient effects of RyR potentiation under physiological conditions. Cardiovasc Res 2014; 103:554-63. [PMID: 24947416 PMCID: PMC4145011 DOI: 10.1093/cvr/cvu158] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Revised: 06/05/2014] [Accepted: 06/15/2014] [Indexed: 11/12/2022] Open
Abstract
AIMS Most of the calcium that activates contraction is released from the sarcoplasmic reticulum (SR) through the ryanodine receptor (RyR). It is controversial whether activators of the RyR produce a maintained increase in the amplitude of the systolic Ca transient. We therefore aimed to examine the effects of activation of the RyR in large animals under conditions designed to be as physiological as possible while simultaneously measuring SR and cytoplasmic Ca. METHODS AND RESULTS Experiments were performed on ventricular myocytes from canine and ovine hearts. Cytoplasmic Ca was measured with fluo-3 and SR Ca with mag-fura-2. Application of caffeine resulted in a brief increase in the amplitude of the systolic Ca transient accompanied by an increase of action potential duration. These effects disappeared with a rate constant of ∼3 s(-1). Similar effects were seen in cells taken from sheep in which heart failure had been induced by rapid pacing. The decrease of Ca transient amplitude was accompanied by a decrease of SR Ca content. During this phase, the maximum (end-diastolic) SR Ca content fell while the minimum systolic increased. CONCLUSIONS This study shows that, under conditions designed to be as physiological as possible, potentiation of RyR opening has no maintained effect on the systolic Ca transient. This result makes it unlikely that potentiation of the RyR has a maintained role in positive inotropy.
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Affiliation(s)
- David J Greensmith
- Unit of Cardiac Physiology, Institute of Cardiovascular Science, Manchester Academic Health Science Centre, 3.18 Core Technology Facility, 46 Grafton Street, Manchester M13 9NT, UK
| | - Gina L J Galli
- Unit of Cardiac Physiology, Institute of Cardiovascular Science, Manchester Academic Health Science Centre, 3.18 Core Technology Facility, 46 Grafton Street, Manchester M13 9NT, UK
| | - Andrew W Trafford
- Unit of Cardiac Physiology, Institute of Cardiovascular Science, Manchester Academic Health Science Centre, 3.18 Core Technology Facility, 46 Grafton Street, Manchester M13 9NT, UK
| | - David A Eisner
- Unit of Cardiac Physiology, Institute of Cardiovascular Science, Manchester Academic Health Science Centre, 3.18 Core Technology Facility, 46 Grafton Street, Manchester M13 9NT, UK
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Greensmith DJ. Ca analysis: an Excel based program for the analysis of intracellular calcium transients including multiple, simultaneous regression analysis. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2013; 113:241-250. [PMID: 24125908 PMCID: PMC3898609 DOI: 10.1016/j.cmpb.2013.09.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Revised: 09/02/2013] [Accepted: 09/09/2013] [Indexed: 06/01/2023]
Abstract
Here I present an Excel based program for the analysis of intracellular Ca transients recorded using fluorescent indicators. The program can perform all the necessary steps which convert recorded raw voltage changes into meaningful physiological information. The program performs two fundamental processes. (1) It can prepare the raw signal by several methods. (2) It can then be used to analyze the prepared data to provide information such as absolute intracellular Ca levels. Also, the rates of change of Ca can be measured using multiple, simultaneous regression analysis. I demonstrate that this program performs equally well as commercially available software, but has numerous advantages, namely creating a simplified, self-contained analysis workflow.
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Affiliation(s)
- David J Greensmith
- Unit of Cardiac Physiology, Institute of Cardiovascular Science, Manchester Academic Health Science Centre, Core Technology Facility, 46 Grafton Street, M13 9NT, UK.
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Greensmith DJ, Nirmalan M. The effects of tumor necrosis factor-alpha on systolic and diastolic function in rat ventricular myocytes. Physiol Rep 2013; 1:e00093. [PMID: 24303157 PMCID: PMC3831905 DOI: 10.1002/phy2.93] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Revised: 08/14/2013] [Accepted: 08/15/2013] [Indexed: 11/20/2022] Open
Abstract
The proinflammatory cytokine tumor necrosis factor-alpha (TNF-α) is associated with myocardial dysfunction observed in sepsis and septic shock. There are two fundamental components to this dysfunction. (1) systolic dysfunction; and (2) diastolic dysfunction. The aim of these experiments was to determine if any aspect of whole-heart dysfunction could be explained by alterations to global intracellular calcium ([Ca2+]i), contractility, and [Ca2+]i handling, by TNF-α, at the level of the individual rat myocyte. We took an integrative approach to simultaneously measure [Ca2+]i, contractility and sarcolemmal Ca fluxes using the Ca indicator fluo-3, video edge detection, and the perforated patch technique, respectively. All experiments were performed at 37°C. The effects of 50 ng/mL TNF-α were immediate and sustained. The amplitude of systolic [Ca2+]i was reduced by 31% and systolic shortening by 19%. Diastolic [Ca2+]i, myocyte length and relaxation rate were not affected, nor were the activity of the [Ca2+]i removal mechanisms. The reduction in systolic [Ca2+]i was associated with a 14% reduction in sarcoplasmic reticulum (SR) content and a 11% decrease in peak L-type Ca current (ICa-L). Ca influx was decreased by 7% associated with a more rapid ICa-L inactivation. These data show that at the level of the myocyte, TNF-α reduces SR Ca which underlies a reduction in systolic [Ca2+]i and thence shortening. Although these findings correlate well with aspects of systolic myocardial dysfunction seen in sepsis, in this model, acutely, TNF-α does not appear to provide a cellular mechanism for sepsis-related diastolic myocardial dysfunction.
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Affiliation(s)
- David J Greensmith
- Unit of Cardiac Physiology, Institute of Cardiovascular Science, Manchester Academic Health Science Centre, Core Technology Facility 46 Grafton Street, Manchester, M13 9NT, U.K
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Micro-arrayed human embryonic stem cells-derived cardiomyocytes for in vitro functional assay. PLoS One 2012; 7:e48483. [PMID: 23152776 PMCID: PMC3495940 DOI: 10.1371/journal.pone.0048483] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Accepted: 10/02/2012] [Indexed: 12/19/2022] Open
Abstract
Introduction The heart is one of the least regenerative organs in the body and any major insult can result in a significant loss of heart cells. The development of an in vitro-based cardiac tissue could be of paramount importance for many aspects of the cardiology research. In this context, we developed an in vitro assay based on human cardiomyocytes (hCMs) and ad hoc micro-technologies, suitable for several applications: from pharmacological analysis to physio-phatological studies on transplantable hCMs. We focused on the development of an assay able to analyze not only hCMs viability, but also their functionality. Methods hCMs were cultured onto a poly-acrylamide hydrogel with tunable tissue-like mechanical properties and organized through micropatterning in a 20×20 array. Arrayed hCMs were characterized by immunofluorescence, GAP-FRAP analyses and live and dead assay. Their functionality was evaluated monitoring the excitation-contraction coupling. Results Micropatterned hCMs maintained the expression of the major cardiac markers (cTnT, cTnI, Cx43, Nkx2.5, α-actinin) and functional properties. The spontaneous contraction frequency was (0.83±0.2) Hz, while exogenous electrical stimulation lead to an increase up to 2 Hz. As proof of concept that our device can be used for screening the effects of pathological conditions, hCMs were exposed to increasing levels of H2O2. Remarkably, hCMs viability was not compromised with exposure to 0.1 mM H2O2, but hCMs contractility was dramatically suppressed. As proof of concept, we also developed a microfluidic platform to selectively treat areas of the cell array, in the perspective of performing multi-parametric assay. Conclusions Such system could be a useful tool for testing the effects of multiple conditions on an in vitro cell model representative of human heart physiology, thus potentially helping the processes of therapy and drug development.
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Kargacin ME, Emmett TL, Kargacin GJ. Epigallocatechin-3-gallate has dual, independent effects on the cardiac sarcoplasmic reticulum/endoplasmic reticulum Ca2+ ATPase. J Muscle Res Cell Motil 2011; 32:89-98. [PMID: 21818690 DOI: 10.1007/s10974-011-9256-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2011] [Accepted: 07/23/2011] [Indexed: 11/25/2022]
Abstract
We determined the effects of epigallocatechin-3-gallate (EGCG) and epicatechin (EC), on pump turnover and Ca2+ transport by the cardiac form of the sarcoplasmic/endoplasmic reticulum Ca2+-ATPase (SERCA). Fluorescence spectroscopy was used to directly measure SERCA ATPase activity and to measure Ca2+ uptake into cardiac sarcoplasmic reticulum (SR) vesicles and microsomes derived from human embryonic kidney (HEK) cells expressing human cardiac SERCA2a. We found that EGCG reduces the maximum velocity of Ca2+ uptake into cardiac SR vesicles and increases the Ca2+-sensitivity of uptake in a concentration-dependent manner. EC is less potent than EGCG in increasing the Ca2+-sensitivity of uptake and does not affect maximum uptake velocity. The EGCG-dependent reduction in Ca2+ uptake velocity is well correlated with direct inhibition of SERCA. The effect of EGCG on the Ca2+-sensitivity of Ca2+ uptake into cardiac SR vesicles is affected by the phosphorylation status of phospholamban (PLB). When cardiac SERCA2a is expressed in HEK cells without PLB, EGCG reduces the maximum velocity of Ca2+ uptake but does not affect the Ca2+-sensitivity of uptake into microsomes derived from these cells indicating that the effect of EGCG on Ca2+-sensitivity requires the presence of PLB. Our results show that EGCG has dual effects on SERCA function in cardiac SR vesicles: it directly affects SERCA by reducing maximum uptake velocity; it increases the Ca2+-sensitivity of Ca2+ uptake in a manner that appears to depend on the interaction between SERCA and PLB.
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Affiliation(s)
- M E Kargacin
- Department of Physiology and Pharmacology, University of Calgary, 3330 Hospital Drive NW, Calgary, AB, T2N 4N1, Canada
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