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Bellis A, Mauro C, Barbato E, Di Gioia G, Sorriento D, Trimarco B, Morisco C. The Rationale of Neprilysin Inhibition in Prevention of Myocardial Ischemia-Reperfusion Injury during ST-Elevation Myocardial Infarction. Cells 2020; 9:cells9092134. [PMID: 32967374 PMCID: PMC7565478 DOI: 10.3390/cells9092134] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 09/17/2020] [Accepted: 09/18/2020] [Indexed: 12/11/2022] Open
Abstract
During the last three decades, timely myocardial reperfusion using either thrombolytic therapy or primary percutaneous intervention (pPCI) has allowed amazing improvements in outcomes with a more than halving in 1-year ST-elevation myocardial infarction (STEMI) mortality. However, mortality and left ventricle (LV) remodeling remain substantial in these patients. As such, novel therapeutic interventions are required to reduce myocardial infarction size, preserve LV systolic function, and improve survival in reperfused-STEMI patients. Myocardial ischemia-reperfusion injury (MIRI) prevention represents the main goal to reach in order to reduce STEMI mortality. There is currently no effective therapy for MIRI prevention in STEMI patients. A significant reason for the weak and inconsistent results obtained in this field may be the presence of multiple, partially redundant, mechanisms of cell death during ischemia-reperfusion, whose relative importance may depend on the conditions. Therefore, it is always more recognized that it is important to consider a "multi-targeted cardioprotective therapy", defined as an additive or synergistic cardioprotective agents or interventions directed to distinct targets with different timing of application (before, during, or after pPCI). Given that some neprilysin (NEP) substrates (natriuretic peptides, angiotensin II, bradykinin, apelins, substance P, and adrenomedullin) exert a cardioprotective effect against ischemia-reperfusion injury, it is conceivable that antagonism of proteolytic activity by this enzyme may be considered in a multi-targeted strategy for MIRI prevention. In this review, by starting from main pathophysiological mechanisms promoting MIRI, we discuss cardioprotective effects of NEP substrates and the potential benefit of NEP pharmacological inhibition in MIRI prevention.
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Affiliation(s)
- Alessandro Bellis
- Dipartimento di Scienze Biomediche Avanzate, Università FEDERICO II, 80131 Napoli, Italy; (A.B.); (E.B.); (G.D.G.); (D.S.); (B.T.)
- Unità Operativa Complessa Cardiologia con UTIC ed Emodinamica—Dipartimento Emergenza Accettazione, Azienda Ospedaliera “Antonio Cardarelli”, 80131 Napoli, Italy;
| | - Ciro Mauro
- Unità Operativa Complessa Cardiologia con UTIC ed Emodinamica—Dipartimento Emergenza Accettazione, Azienda Ospedaliera “Antonio Cardarelli”, 80131 Napoli, Italy;
| | - Emanuele Barbato
- Dipartimento di Scienze Biomediche Avanzate, Università FEDERICO II, 80131 Napoli, Italy; (A.B.); (E.B.); (G.D.G.); (D.S.); (B.T.)
| | - Giuseppe Di Gioia
- Dipartimento di Scienze Biomediche Avanzate, Università FEDERICO II, 80131 Napoli, Italy; (A.B.); (E.B.); (G.D.G.); (D.S.); (B.T.)
- Cardiac Catheterization Laboratory, Montevergine Clinic, 83013 Mercogliano (AV), Italy
| | - Daniela Sorriento
- Dipartimento di Scienze Biomediche Avanzate, Università FEDERICO II, 80131 Napoli, Italy; (A.B.); (E.B.); (G.D.G.); (D.S.); (B.T.)
| | - Bruno Trimarco
- Dipartimento di Scienze Biomediche Avanzate, Università FEDERICO II, 80131 Napoli, Italy; (A.B.); (E.B.); (G.D.G.); (D.S.); (B.T.)
| | - Carmine Morisco
- Dipartimento di Scienze Biomediche Avanzate, Università FEDERICO II, 80131 Napoli, Italy; (A.B.); (E.B.); (G.D.G.); (D.S.); (B.T.)
- Correspondence: ; Tel.: +39-081-746-2253; Fax: +39-081-746-2256
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Yu Y, Zhang M, Hu Y, Zhao Y, Teng F, Lv X, Li J, Zhang Y, Hatch GM, Chen L. Increased Bioavailable Berberine Protects Against Myocardial Ischemia Reperfusion Injury Through Attenuation of NFκB and JNK Signaling Pathways. Int Heart J 2018; 59:1378-1388. [DOI: 10.1536/ihj.17-458] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Affiliation(s)
- Yang Yu
- Department of Pharmacology, College of Basic Medical Sciences, School of Nursing, Jilin University
| | - Ming Zhang
- Department of Pharmacology, College of Basic Medical Sciences, School of Nursing, Jilin University
| | - Yali Hu
- Department of Pharmacology, College of Basic Medical Sciences, School of Nursing, Jilin University
| | - Yali Zhao
- Department of Pharmacology, College of Basic Medical Sciences, School of Nursing, Jilin University
| | - Fei Teng
- Department of Pharmacology, College of Basic Medical Sciences, School of Nursing, Jilin University
| | - Xiaoyan Lv
- Department of Pharmacology, College of Basic Medical Sciences, School of Nursing, Jilin University
| | - Ji Li
- Department of Pharmacology, College of Basic Medical Sciences, School of Nursing, Jilin University
| | - Ying Zhang
- Department of Neurology and Neuroscience Center, First Hospital of Jilin University
| | - Grant M. Hatch
- Department of Pharmacology & Therapeutics, University of Manitoba, Manitoba Institute of Child Health
| | - Li Chen
- Department of Pharmacology, College of Basic Medical Sciences, School of Nursing, Jilin University
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Reperfusing the myocardium - a damocles Sword. Indian Heart J 2018; 70:433-438. [PMID: 29961464 PMCID: PMC6034085 DOI: 10.1016/j.ihj.2017.11.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Revised: 10/03/2017] [Accepted: 11/07/2017] [Indexed: 12/11/2022] Open
Abstract
Return of blood flow after periodic ischemia is often accompanied by myocardial injury, commonly known as lethal reperfusion injury (RI). Experimental studies have shown that 50% of muscle die of ischemia and another 50% die because of reperfusion. It is characterized by myocardial, vascular, or electrophysiological dysfunction that is induced by the restoration of blood flow to previously ischemic tissue. This phenomenon reduces the efficiency of the present modalities used to combat the ischemic myocardium. Moreover, despite an improved understanding of the pathophysiology of this process and encouraging preclinical trials of multiple agents, most of the clinical trials to prevent RI have been disappointing and leaves us at ground zero to explore newer approaches.
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Ferrari R, Balla C, Malagù M, Guardigli G, Morciano G, Bertini M, Biscaglia S, Campo G. Reperfusion Damage - A Story of Success, Failure, and Hope. Circ J 2016; 81:131-141. [PMID: 27941300 DOI: 10.1253/circj.cj-16-1124] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Tissue salvage of severely ischemic myocardium requires timely reperfusion by thrombolysis, angioplasty, or bypass. However, recovery of left ventricular function is rare. It may be absent or, even worse, reperfusion can induce further damage. Laboratory studies have shown convincingly that reperfusion can increase injury over and above that attributable to the pre-existing ischemia, precipitating arrhythmias, suppressing the recovery of contractile function ("stunning") and possibly even causing cell death in potentially salvable ischemic tissue. The mechanisms of reperfusion injury have been widely studied and, in the laboratory, it can be attenuated or prevented. Disappointingly, this is not the case in the clinic, particularly after thrombolysis or primary angioplasty. In contrast, excellent results have been achieved by surgeons by means of cardioplegia and hypothermia. For the interventionist, the issue is more complex as, contrary to cardiac surgery where the cardioplegia can be applied before ischemia and the heart can be stopped, during an angioplasty the heart still has to beat to support the circulation. We analyze in detail all these issues.
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Affiliation(s)
- Roberto Ferrari
- Cardiovascular and LTTA Centre, Azienda Ospedaliera-Universitaria di Ferrara
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Chen Z, Wu D, Li L, Chen L. Apelin/APJ System: A Novel Therapeutic Target for Myocardial Ischemia/Reperfusion Injury. DNA Cell Biol 2016; 35:766-775. [DOI: 10.1089/dna.2016.3391] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Affiliation(s)
- Zhe Chen
- Institute of Pharmacy and Pharmacology, Hunan Province Cooperative Innovation Center for Molecular Target New Drugs Study, University of South China, Hengyang, China
| | - Di Wu
- Institute of Pharmacy and Pharmacology, Hunan Province Cooperative Innovation Center for Molecular Target New Drugs Study, University of South China, Hengyang, China
| | - Lanfang Li
- Institute of Pharmacy and Pharmacology, Hunan Province Cooperative Innovation Center for Molecular Target New Drugs Study, University of South China, Hengyang, China
| | - Linxi Chen
- Institute of Pharmacy and Pharmacology, Hunan Province Cooperative Innovation Center for Molecular Target New Drugs Study, University of South China, Hengyang, China
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Ferrari R, Biscaglia S, Malagù M, Bertini M, Campo G. Can We Improve Myocardial Protection during Ischaemic Injury? Cardiology 2016; 135:14-26. [DOI: 10.1159/000444847] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Accepted: 02/19/2016] [Indexed: 11/19/2022]
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Kim MJ, Ro YS, Shin SD, Song KJ, Ahn KO, Hong SO, Kim YT. Association of emergent and elective percutaneous coronary intervention with neurological outcome and survival after out-of-hospital cardiac arrest in patients with and without a history of heart disease. Resuscitation 2015; 97:115-21. [DOI: 10.1016/j.resuscitation.2015.08.019] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Revised: 08/19/2015] [Accepted: 08/23/2015] [Indexed: 10/23/2022]
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Ashraf MI, Fries D, Streif W, Aigner F, Hengster P, Troppmair J, Hermann M. Biopsychronology: live confocal imaging of biopsies to assess organ function. Transpl Int 2014; 27:868-76. [DOI: 10.1111/tri.12338] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Revised: 10/20/2013] [Accepted: 04/13/2014] [Indexed: 01/23/2023]
Affiliation(s)
- Muhammad Imtiaz Ashraf
- Daniel Swarovski Research Laboratory; Department of Visceral-, Transplant- and Thoracic Surgery; Center of Operative Medicine; Medical University Innsbruck; Innsbruck Austria
| | - Dietmar Fries
- Department of Anesthesiology and Critical Care Medicine; Medical University Innsbruck; Innsbruck Austria
| | - Werner Streif
- Department of Pediatrics I; Innsbruck Medical University; Innsbruck Austria
| | - Felix Aigner
- Daniel Swarovski Research Laboratory; Department of Visceral-, Transplant- and Thoracic Surgery; Center of Operative Medicine; Medical University Innsbruck; Innsbruck Austria
| | - Paul Hengster
- Daniel Swarovski Research Laboratory; Department of Visceral-, Transplant- and Thoracic Surgery; Center of Operative Medicine; Medical University Innsbruck; Innsbruck Austria
| | - Jakob Troppmair
- Daniel Swarovski Research Laboratory; Department of Visceral-, Transplant- and Thoracic Surgery; Center of Operative Medicine; Medical University Innsbruck; Innsbruck Austria
| | - Martin Hermann
- Department of Anesthesiology and Critical Care Medicine; Medical University Innsbruck; Innsbruck Austria
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Ashraf MI, Ebner M, Wallner C, Haller M, Khalid S, Schwelberger H, Koziel K, Enthammer M, Hermann M, Sickinger S, Soleiman A, Steger C, Vallant S, Sucher R, Brandacher G, Santer P, Dragun D, Troppmair J. A p38MAPK/MK2 signaling pathway leading to redox stress, cell death and ischemia/reperfusion injury. Cell Commun Signal 2014; 12:6. [PMID: 24423080 PMCID: PMC3896752 DOI: 10.1186/1478-811x-12-6] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Accepted: 01/04/2014] [Indexed: 12/29/2022] Open
Abstract
Background Many diseases and pathological conditions are characterized by transient or constitutive overproduction of reactive oxygen species (ROS). ROS are causal for ischemia/reperfusion (IR)-associated tissue injury (IRI), a major contributor to organ dysfunction or failure. Preventing IRI with antioxidants failed in the clinic, most likely due to the difficulty to timely and efficiently target them to the site of ROS production and action. IR is also characterized by changes in the activity of intracellular signaling molecules including the stress kinase p38MAPK. While ROS can cause the activation of p38MAPK, we recently obtained in vitro evidence that p38MAPK activation is responsible for elevated mitochondrial ROS levels, thus suggesting a role for p38MAPK upstream of ROS and their damaging effects. Results Here we identified p38MAPKα as the predominantly expressed isoform in HL-1 cardiomyocytes and siRNA-mediated knockdown demonstrated the pro-oxidant role of p38MAPKα signaling. Moreover, the knockout of the p38MAPK effector MAPKAP kinase 2 (MK2) reproduced the effect of inhibiting or knocking down p38MAPK. To translate these findings into a setting closer to the clinic a stringent kidney clamping model was used. p38MAPK activity increased upon reperfusion and p38MAPK inhibition by the inhibitor BIRB796 almost completely prevented severe functional impairment caused by IR. Histological and molecular analyses showed that protection resulted from decreased redox stress and apoptotic cell death. Conclusions These data highlight a novel and important mechanism for p38MAPK to cause IRI and suggest it as a potential therapeutic target for prevention of tissue injury.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Jakob Troppmair
- Daniel Swarovski Research Laboratory, Department of Visceral, Transplant- and Thoracic Surgery, Innsbruck Medical University (IMU), Innrain 66, 6020 Innsbruck, Austria.
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Fröhlich GM, Meier P, White SK, Yellon DM, Hausenloy DJ. Myocardial reperfusion injury: looking beyond primary PCI. Eur Heart J 2013; 34:1714-22. [PMID: 23536610 DOI: 10.1093/eurheartj/eht090] [Citation(s) in RCA: 287] [Impact Index Per Article: 26.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Coronary heart disease (CHD) is the leading cause of death and disability in Europe. For patients presenting with an acute ST-segment elevation myocardial infarction (STEMI), timely myocardial reperfusion using either thrombolytic therapy or primary percutaneous coronary intervention (PPCI) is the most effective therapy for limiting myocardial infarct (MI) size, preserving left-ventricular systolic function and reducing the onset of heart failure. Despite this, the morbidity and mortality of STEMI patients remain significant, and novel therapeutic interventions are required to improve clinical outcomes in this patient group. Paradoxically, the process of myocardial reperfusion can itself induce cardiomyocyte death-a phenomenon which has been termed 'myocardial reperfusion injury' (RI), the irreversible consequences of which include microvascular obstruction and myocardial infarction. Unfortunately, there is currently no effective therapy for preventing myocardial RI in STEMI patients making it an important residual target for cardioprotection. Previous attempts to translate cardioprotective therapies (antioxidants, calcium-channel blockers, and anti-inflammatory agents) for reducing RI into the clinic, have been unsuccessful. An improved understanding of the pathophysiological mechanisms underlying RI has resulted in the identification of several promising mechanical (ischaemic post-conditioning, remote ischaemic pre-conditioning, therapeutic hypothermia, and hyperoxaemia), and pharmacological (atrial natriuretic peptide, cyclosporin-A, and exenatide) therapeutic strategies, for preventing myocardial RI, many of which have shown promise in initial proof-of-principle clinical studies. In this article, we review the pathophysiology underlying myocardial RI, and highlight the potential therapeutic interventions which may be used in the future to prevent RI and improve clinical outcomes in patients with CHD.
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Affiliation(s)
- Georg M Fröhlich
- The Heart Hospital, University College London Hospitals, 16-18 Westmoreland Street, W1G 8PH, London, UK
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Feng M, Xiang JZ, Ming ZY, Fu Q, Ma R, Zhang QF, Dun YY, Yang L, Liu H. Activation of epidermal growth factor receptor mediates reperfusion arrhythmias in anaesthetized rats. Cardiovasc Res 2011; 93:60-8. [PMID: 22028338 DOI: 10.1093/cvr/cvr281] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
AIMS Epidermal growth factor receptor (EGFR) plays a critical role in the development and function of the heart. Previous studies have demonstrated that EGFR is involved in regulating electrical excitability of the heart. The present study was designed to investigate whether EGFR activation would mediate cardiac arrhythmias induced by reperfusion in anaesthetized rats. METHODS AND RESULTS Reperfusion arrhythmias were induced by 10 min ligation of the left anterior descending coronary artery, followed by a 30 min reperfusion in anaesthetized rats. The incidence and severity of cardiac arrhythmias were significantly reduced by pre-treatment with the EGFR kinase inhibitor AG556. The phosphorylation level of myocardial EGFR was increased during ischaemia and at early reperfusion. Intramyocardial transfection of EGFR siRNA reduced EGFR mRNA and protein, and decreased the incidence of ventricular fibrillation induced by reperfusion. Interestingly, tyrosine phosphorylation levels of cardiac Na(+) channels (I(Na)) and L-type Ca(2+) channels (I(Ca,L)) were significantly increased at time points corresponding to the alteration of EGFR phosphorylation levels during reperfusion. AG556 pre-treatment countered the increased tyrosine phosphorylation level of Na(+) and L-type Ca(2+) channels induced by reperfusion. Patch-clamp studies proved that AG556 could inhibit I(Na) and I(Ca,L) in rat ventricular myocytes. No significant alteration was observed in tyrosine phosphorylation levels of cardiac Kv4.2 and Kir2.1 channels during reperfusion. CONCLUSION These results demonstrate for the first time that EGFR plays an important role in the genesis of arrhythmias induced by reperfusion, which is likely mediated at least in part by enhancing tyrosine phosphorylation of cardiac Na(+) and L-type Ca(2+) channels.
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Affiliation(s)
- Mei Feng
- Department of Pharmacology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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Abstract
The occurrence of myocardial ischaemia will result in either reversible or irreversible myocardial dysfunction. Even when revascularization is successful, some reperfusion injury may occur that transiently impairs myocardial function. Therefore, treatment should not only be directed towards prompt restoration of myocardial blood flow but measures should also be taken to prevent or alleviate the consequences of myocardial reperfusion injury. Over the years, various strategies have been developed. The present contribution reviews a number of these strategies focusing on pharmacological treatments that have been developed to address myocardial reperfusion injury.
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Joyner-Matos J, Downs CA, Julian D. Increased expression of stress proteins in the surf clam Donax variabilis following hydrogen sulfide exposure. Comp Biochem Physiol A Mol Integr Physiol 2006; 145:245-57. [PMID: 16890466 DOI: 10.1016/j.cbpa.2006.06.033] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2006] [Revised: 06/21/2006] [Accepted: 06/22/2006] [Indexed: 11/21/2022]
Abstract
Endogenous free radical production and resulting oxidative damage may result from exposure to hypoxia, hyperoxia, or hydrogen sulfide. Previous investigations of sulfide-induced oxidative damage have produced conflicting results, perhaps because these studies utilized species presumably adapted to sulfide. We examined the effects of sulfide, hypoxia and hyperoxia on the surf clam Donax variabilis to test whether these stressors induce a cellular response to oxidative stress. These clams inhabit high-energy sandy beaches and are unlikely to have specific adaptations to these stressors. In duplicate flow-through experiments performed in fall and spring, clams were exposed to normoxia (22 kPa P(O(2))), hypoxia (10 kPa), hyperoxia (37 kPa), or sulfide with normoxia ( approximately 100 mumol L(-1), 22 kPa respectively) for 24 h. We quantified whole-animal expression of three antioxidants (Cu/Zn and Mn superoxide dismutases, glutathione peroxidase), a lipid peroxidation marker (4-hydroxy-2E-nonenol-adducted protein), a DNA repair enzyme (OGG1-m), four heat shock proteins (small Hsp, Hsp60, Hsp70, and mitochondrial Hsp70), ubiquitin, and actin. Clams exposed to sulfide showed upregulation of the greatest number of stress proteins and the pattern was consistent with a cellular response to oxidative stress. Furthermore, there was a marked seasonality, with greater stress protein expression in clams from the spring.
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Yardim-Akaydin S, Kesimer M, Imren E, Sepici A, Simşek B, Torun M. Urate oxidation during percutaneous transluminal coronary angioplasty and thrombolysis in patients with coronary artery disease. Clin Chim Acta 2005; 362:131-7. [PMID: 15992789 DOI: 10.1016/j.cccn.2005.06.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2005] [Revised: 06/03/2005] [Accepted: 06/06/2005] [Indexed: 12/15/2022]
Abstract
Thrombolysis and percutaneous transluminal coronary angioplasty (PTCA) are kinds of procedures that can be used to restore the blood flow of previously ischemic myocardium that can be the result of excessive production of reactive oxygen and nitrogen species, such as superoxide and hydroxyl radical, hypochlorous acid and peroxynitrite. Reaction of urate with some of these potent oxidants results in allantoin production. In this study, we measured the serum allantoin levels, an oxidation product of urate, and "in vivo" marker of free radical generation in reperfusion of ischemic myocardium. After an overnight fasting state, blood samples were collected from 35 patients with coronary occlusive diseases (7 women and 28 men) and 31 healthy subjects (8 women and 23 men). Serum allantoin and urate levels were measured by a GC-MS method. Serum allantoin levels of patients on PTCA therapy (mean+/-SD, 27.4 +/- 15.2 micromol/l) and thrombolytic therapy (24.6 +/- 8.6 micromol/l) were significantly higher than those of the patients without therapy (15.8 +/- 6.2 micromol/l, p < 0.05 with PTCA and p < 0.006 with thrombolysis) and healthy controls (12.6 +/- 6.3 micromol/l, p < 0.002 with PTCA and p < 0.0001 with thrombolysis). Although serum urate levels in PTCA (380.1 +/- 72.6 micromol/l) and thrombolysis (359.5 +/- 60.0 micromol/l) were higher than those in the non-therapy patients (336.6 +/- 53.8 micromol/l) and controls (318.3 +/- 81.0 micromol/l), there were no significant differences among groups (p > 0.05). The results of the study are consistent with others which have demonstrated, higher urate levels are associated with coronary occlusive diseases. Our data support the hypothesis that generation of ROS occurs during myocardial reperfusion. Increased allantoin levels may be used as an index of increased oxidative stress during reperfusion.
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Affiliation(s)
- Sevgi Yardim-Akaydin
- Gazi University, Faculty of Pharmacy, Department of Biochemistry, Etiler-Ankara, Turkey.
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Ott HC, Berjukow S, Marksteiner R, Margreiter E, Böck G, Laufer G, Hering S. On the fate of skeletal myoblasts in a cardiac environment: down-regulation of voltage-gated ion channels. J Physiol 2004; 558:793-805. [PMID: 15194742 PMCID: PMC1665019 DOI: 10.1113/jphysiol.2003.060186] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
We have analysed the voltage-gated ion channels and fusion competence of skeletal muscle myoblasts labelled with green fluorescent protein (GFP) and the membrane dye PKH transplanted into the infarcted myocardium of syngenic rats. After cell transplantation the animals were killed and GFP(+)-PKH(+) myoblasts enzymatically isolated for subsequent studies of ionic currents through voltage-gated sodium, calcium and potassium channels. A down-regulation of all three types of ion channels after engraftment was observed. The fraction of cells with calcium (68%) and sodium channels (65%) declined to zero within 24 h and 1 week, respectively. Down-regulation of potassium currents (90% in control) occurred within 2 weeks to about 30%. Before injection myoblasts expressed predominantly transient outward potassium channels whereas after isolation from the myocardium exclusively rapid delayed rectifier channels. The currents recovered completely between 1 and 6 weeks under cell culture conditions. The down-regulation of ion channels and changes in potassium current kinetics suggest that the environment provided by infarcted myocardium affects expression of voltage-gated ion channels of skeletal myoblasts.
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Affiliation(s)
- H C Ott
- Institute of Pharmacology and Toxicology, University of Vienna, Althanstrasse 14, A-1090 Vienna
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Marczin N, El-Habashi N, Hoare GS, Bundy RE, Yacoub M. Antioxidants in myocardial ischemia-reperfusion injury: therapeutic potential and basic mechanisms. Arch Biochem Biophys 2004; 420:222-36. [PMID: 14654061 DOI: 10.1016/j.abb.2003.08.037] [Citation(s) in RCA: 112] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Oxidative stress is a constant threat to all living organisms and an immense repertoire of cellular defense systems is being employed by most pro- and eukaryotic systems to eliminate or to attenuate oxidative stress. Ischemia and reperfusion is characterized by both a significant oxidative stress and characteristic changes in the antioxidant defense. By focusing on this antioxidant response of the cardiovascular system in the setting of ischemia-reperfusion injury, the aim of this review was threefold. First, based on recent animal experiments and clinical studies we shall discuss how endogenous antioxidants respond to oxidative stress during ischemia-reperfusion injury and highlight the results of recent trials on the ability of antioxidants to modulate ischemia-reperfusion injury. In this aspect, we will particularly focus on the emerging concept that various lines of antioxidant defenses do not act individually but are linked to each other in a systematic relationship as part of an antioxidant network. It is well known that enzymatic mechanisms are important components of the endogenous antioxidant repertoire; however, the relative importance of the different enzyme systems and isoforms has been much debated. The second part will focus on recent suggestions attributing a potentially key role of mitochondrial MnSOD in cardiac ischemia-reperfusion injury. Finally, the third part of the review will critically examine how endogenous antioxidants might regulate the complex signal transduction pathways of cellular activation with particular attention to the NF-kappaB and MAPK systems that appears to determine outcome of injury, survival, and adaptation.
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Affiliation(s)
- Nándor Marczin
- Department of Cardiothoracic Surgery, Imperial College London, Faculty of Medicine, National Heart and Lung Institute at the Heart Science Centre, Harefield Hospital, Harefield, Middlesex UB9 6JH, UK.
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Davani EY, Brumme Z, Singhera GK, Côté HCF, Harrigan PR, Dorscheid DR. Insulin-like growth factor-1 protects ischemic murine myocardium from ischemia/reperfusion associated injury. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2003; 7:R176-83. [PMID: 14624693 PMCID: PMC374373 DOI: 10.1186/cc2375] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/26/2003] [Revised: 08/04/2003] [Accepted: 08/18/2003] [Indexed: 11/10/2022]
Abstract
INTRODUCTION Ischemia/reperfusion occurs in myocardial infarction, cardiac dysfunction during sepsis, cardiac transplantation and coronary artery bypass grafting, and results in injury to the myocardium. Although reperfusion injury is related to the nature and duration of ischemia, it is also a separate entity that may jeopardize viable cells and ultimately may impair cardiac performance once ischemia is resolved and the organ heals. METHOD The present study was conducted in an ex vivo murine model of myocardial ischemia/reperfusion injury. After 20 min of ischemia, isolated hearts were perfused for up to 2 hours with solution (modified Kreb's) only, solution plus insulin-like growth factor (IGF)-1, or solution plus tumor necrosis factor (TNF)-alpha. Cardiac contractility was monitored continuously during this period of reperfusion. RESULTS On the basis of histologic evidence, IGF-1 prevented reperfusion injury as compared with TNF-alpha; TNF-alpha increased perivascular interstitial edema and disrupted tissue lattice integrity, whereas IGF-1 maintained myocardial cellular integrity and did not increase edema. Also, there was a significant reduction in detectable creatine phosphokinase in the perfusate from IGF-1 treated hearts. By recording transduced pressures generated during the cardiac cycle, reperfusion with IGF-1 was accompanied by markedly improved cardiac performance as compared with reperfusion with TNF-alpha or modified Kreb's solution only. The histologic and functional improvement generated by IGF-1 was characterized by maintenance of the ratio of mitochondrial to nuclear DNA within heart tissue. CONCLUSION We conclude that IGF-1 protects ischemic myocardium from further reperfusion injury, and that this may involve mitochondria-dependent mechanisms.
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Affiliation(s)
- Ehsan Y Davani
- Graduate Student, University of British Columbia, McDonald Research Laboratories/iCAPTURE Center, St Paul's Hospital, Vancouver, British Columbia, Canada
| | - Zabrina Brumme
- Graduate Student, University of British Columbia, BC Centre for Excellence in HIV/AIDS, St Paul's Hospital, Vancouver, British Columbia, Canada
| | - Gurpreet K Singhera
- Post-Doctoral Fellow, University of British Columbia, McDonald Research Laboratories/iCAPTURE Center, St Paul's Hospital, Vancouver, British Columbia, Canada
| | - Hélène CF Côté
- Post-Doctoral Fellow, University of British Columbia, BC Centre for Excellence in HIV/AIDS, St Paul's Hospital, Vancouver, British Columbia, Canada
| | - P Richard Harrigan
- Clinical Assistant, Professor of Medicine, University of British Columbia, BC Centre for Excellence in HIV/AIDS, St Paul's Hospital, Vancouver, British Columbia, Canada
| | - Delbert R Dorscheid
- Assistant Professor of Medicine, University of British Columbia, McDonald Research Laboratories/iCAPTURE Center, St Paul's Hospital, Vancouver, British Columbia, Canada
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Abou El Hassan MAI, Heijn M, Rabelink MJWE, van der Vijgh WJF, Bast A, Hoeben RC. The protective effect of cardiac gene transfer of CuZn-sod in comparison with the cardioprotector monohydroxyethylrutoside against doxorubicin-induced cardiotoxicity in cultured cells. Cancer Gene Ther 2003; 10:270-7. [PMID: 12679799 DOI: 10.1038/sj.cgt.7700564] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Doxorubicin-induced cardiotoxicity is related to its production of free radicals that specifically affect heart tissue because of its low antioxidant status. Monohydroxyethylrutoside (monoHER), a potent antioxidant flavonoid, is under development as a protector against doxorubicin-induced cardiotoxicity. The overexpression of high levels of superoxide dismutase (sod) protects against free radical damage in transgenic mice. Seeking alternatives besides the few cardioprotectors that are presently under investigation, the aim of the present study was to investigate the protective effect of cardiac gene transfer of CuZn-sod compared with that of the presently most promising cardioprotector monoHER against doxorubicin-induced cardiotoxic effects on neonatal rat cardiac myocytes (NeRCaMs) in vitro. NeRCaMs were infected with different multiplicity of infections (MOIs) of adenovirus encoding CuZn-sod (AdCuZn-sod). A control infection with an adenovirus vector encoding a nonrelated protein was included. The overexpression of CuZn-sod was characterized within 3 days postinfection. For doxorubicin treatment, NeRCaMs were divided into three groups. The first group was infected with AdCuZn-sod before treatment with doxorubicin (0-50 microM). The second and third groups were treated with doxorubicin (0-50 microM) alone and with 1 mM monoHER, respectively. The LDH release and survival of treated cells were measured 24 and 48 hours after doxorubicin treatment. The beating rate was followed during the 3 days after doxorubicin (0-100 microM) treatment. At the third day after infection with an MOI of 25 plaque-forming unit (PFU) of AdCuZn-sod/cell, the activity of CuZn-sod significantly increased (five-fold, P=.029). Higher MOI produced cytopathic effects (CPEs). Doxorubicin alone produced significant concentration- and time-dependent reduction in NeRCaMs beating rate and survival (P < .0005). Doxorubicin (> or =50 microM)-treated cells ceased to beat after 24 hours. This cytotoxicity was associated with an increase in the LDH release from the treated cells (P <.0005). The five-fold increase in the activity of CuZn-sod did not protect against any of the cytotoxic effects of doxorubicin on NeRCaMs. In contrast, monoHER (1 mM) protected against the lethal effects of doxorubicin on the survival, LDH release and the beating rate of NeRCaMs (P <.004) during 48 hours after doxorubicin treatment. Doxorubicin-treated (< or =100 microM) cells continued beating for >72 hours in the presence of monoHER. The present study showed the lack of adenoviral CuZn-sod gene-transfer to protect myocardiocytes against doxorubicin-induced toxicity and confirms the efficacy of monoHER cardioprotection. Thus, a gene-therapy strategy involving overexpression of CuZn-sod to protect against doxorubicin-induced cardiotoxicity is not feasible with the currently available adenovirus vectors.
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Affiliation(s)
- M A I Abou El Hassan
- Department of Medical Oncology, Free University Medical Center, PO Box 7057, 1007 MB Amsterdam, The Netherlands.
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19
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Inoue T, Ku K, Kaneda T, Zang Z, Otaki M, Oku H. Cardioprotective effects of lowering oxygen tension after aortic unclamping on cardiopulmonary bypass during coronary artery bypass grafting. Circ J 2002; 66:718-22. [PMID: 12197594 DOI: 10.1253/circj.66.718] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The effect on myocardial reperfusion injury of reducing oxygen tension during reperfusion on cardiopulmonary bypass (CPB) in coronary artery bypass grafting (CABG) was examined at the same time as the influence of diltiazem during CPB was evaluated. A prospective, randomized trial evaluated the hemodynamic and myocardial metabolic recovery in 3 groups of patients undergoing elective CABG; subjects were randomly allocated on the basis of oxygen tension during reperfusion after aortic unclamping: group 1 (n=10) hyperoxic reperfusion (oxygen tension [PO2]=450-550 mmHg); group 2 (n=10): hyperoxic reperfusion and subsequent continuous infusion of diltiazem (0.5 microg/kg); group 3 (n=10): lowering reperfusate PO2 (PO2=200-250 mmHg). Hemodynamic and myocardial metabolic measurements were taken at 6 preset times: before starting the surgical procedure and at 30 min and 3, 9, 21, and 45 h after discontinuation of CPB. The cardiac index in the lowering reperfusate PO2 group was higher than that of the hyperoxic reperfusion groups at 30 min and 3 h after CPB, and malondialdehyde and troponin-T were significantly lower at 30 min and 3 h, respectively. In comparison with the hyperoxic + diltiazem group, the hemodynamic and myocardial recovery in the lowering reperfusate PO2 group was improved for about 3 h after CPB. Reduced oxygen tension during reperfusion after aortic unclamping on CPB is more effective against myocardial injury than a calcium antagonist in the short term. It is a convenient and safe management technique that can reduce morbidity and mortality, especially in the severely compromised heart.
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Affiliation(s)
- Takehiro Inoue
- Department of Cardiovascular Surgery, Kinki University School of Medicine, Osaka-Sayama, Osaka, Japan.
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20
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Narayan P, Mentzer RM, Lasley RD. Annexin V staining during reperfusion detects cardiomyocytes with unique properties. Am J Physiol Heart Circ Physiol 2001; 281:H1931-7. [PMID: 11668053 DOI: 10.1152/ajpheart.2001.281.5.h1931] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
With the use of markers of sarcolemmal membrane permeability, cardiomyocyte models of ischemic injury have primarily addressed necrotic death during ischemia. In the present study, we used annexin V-propidium iodide staining to examine apoptosis and necrosis after simulated ischemia and simulated reperfusion in rat ventricular myocytes. Annexin V binds phosphatidylserine, a phosphoaminolipid thought to be externalized during apoptosis or programmed cell death. Propidium iodide is a marker of cell necrosis. Under baseline conditions, <1% of cardiomyocytes stained positive for annexin V. After 20 or 60 min of simulated ischemia, there was no increase in annexin V staining, although 60-min simulated ischemia resulted in significant propidium iodide staining. Twenty minutes of simulated ischemia, followed by 20 or 60 min of simulated reperfusion, resulted in 8-10% of myocytes staining positive for annexin V. Annexin V-positive cells retained both rod-shaped morphology and contractile function but exhibited the decreased cell width indicative of cell shrinkage. Baseline mitochondrial free Ca2+ (111 +/- 14 nM) was elevated in reperfused annexin V-negative cells (214 +/- 22 nM), and further elevated in annexin V-positive myocytes (382 +/- 9 nM). After 60 min of simulated reperfusion, caspase-3-like activity was observed in approximately 3% of myocytes, which had a rounded appearance and membrane blebs. These results suggest that the use of annexin V after simulated ischemia-reperfusion uncovers a population of cardiomyocytes whose characteristics appear to be consistent with cells undergoing apoptosis.
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Affiliation(s)
- P Narayan
- Department of Surgery, University of Kentucky College of Medicine, Lexington, Kentucky 40536, USA.
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Bosetti F, Yu G, Zucchi R, Ronca-Testoni S, Solaini G. Myocardial ischemic preconditioning and mitochondrial F1F0-ATPase activity. Mol Cell Biochem 2000; 215:31-7. [PMID: 11204453 DOI: 10.1023/a:1026558922596] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
A short period of ischemia followed by reperfusion (ischemic preconditioning) is known to trigger mechanisms that contribute to the prevention of ATP depletion. In ischemic conditions, most of the ATP hydrolysis can be attributed to mitochondrial F1F0-ATPase (ATP synthase). The purpose of the present study was to examine the effect of myocardial ischemic preconditioning on the kinetics of ATP hydrolysis by F1F0-ATPase. Preconditioning was accomplished by three 3-min periods of global ischemia separated by 3 min of reperfusion. Steady state ATP hydrolysis rates in both control and preconditioned mitochondria were not significantly different. This suggests that a large influence of the enzyme on the preconditioning mechanism may be excluded. However, the time required by the reaction to reach the steady state rate was increased in the preconditioned group before sustained ischemia, and it was even more enhanced in the first 5 min of reperfusion (101 +/- 3.0 sec in preconditioned vs. 83.4 +/- 4.4 sec in controls, p < 0.05). These results suggest that this transient increase in activation time may contribute to the cardioprotection by slowing the ATP depletion in the very critical early phase of post-ischemic reperfusion.
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Affiliation(s)
- F Bosetti
- Scuola Superiore di Studi Universitari e di Perfezionamento S. Anna, Pisa, Italy
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22
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Napoli C, Cicala C, Wallace JL, de Nigris F, Santagada V, Caliendo G, Franconi F, Ignarro LJ, Cirino G. Protease-activated receptor-2 modulates myocardial ischemia-reperfusion injury in the rat heart. Proc Natl Acad Sci U S A 2000; 97:3678-83. [PMID: 10737808 PMCID: PMC16299 DOI: 10.1073/pnas.97.7.3678] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Protease-activated receptor-2 (PAR-2) is a member of seven transmembrane domain G protein-coupled receptors activated by proteolytic cleavage whose better known member is the thrombin receptor. The pathophysiological role of PAR-2 remains poorly understood. Because PAR-2 is involved in inflammatory and injury response events, we investigated the role of PAR-2 in experimental myocardial ischemia-reperfusion injury. We show for the first time that PAR-2 activation protects against reperfusion-injury. After PAR-2-activating peptide (2AP) infusion, we found a significant recovery of myocardial function and decrease in oxidation at reflow. Indeed, the glutathione cycle (glutathione and oxidized glutathione) and lipid peroxidation analysis showed a reduced oxidative reperfusion-injury. Moreover, ischemic risk zone and creatine kinase release were decreased after PAR-2AP treatment. These events were coupled to elevation of PAR-2 and tumor necrosis factor alpha (TNFalpha) expression in both nuclear extracts and whole heart homogenates. The recovery of coronary flow was not reverted by L-nitroarginine methylester, indicating a NO-independent pathway for this effect. Genistein, a tyrosine kinase inhibitor, did not revert the PAR-2AP effect. During early reperfusion injury in vivo not only oxygen radicals are produced but also numerous proinflammatory mediators promoting neutrophil and monocyte targeting. In this context, we show that TNFalpha and PAR-2 are involved in signaling in pathophysiological conditions, such as myocardial ischemia-reperfusion. At the same time, because TNFalpha may exert pro-inflammatory actions and PAR-2 may constitute one of the first protective mechanisms that signals a primary inflammatory response, our data support the concept that this network may regulate body responses to tissue injury.
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Affiliation(s)
- C Napoli
- Department of Clinical and Experimental Medicine, Federico II University of Naples, Naples 80131 Italy
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23
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Elliott GT, Mei DA, Gross GJ. Monophosphoryl lipid A attenuates myocardial stunning in dogs: role of ATP-sensitive potassium channels. J Cardiovasc Pharmacol 1998; 32:49-56. [PMID: 9676720 DOI: 10.1097/00005344-199807000-00008] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Results of previous studies indicate that monophosphoryl lipid A (MLA) reduces myocardial infarct size when administered 24 but not 1 h before a prolonged period of regional ischemia in dogs and rabbits. This cardioprotective effect of MLA could be reversed by the administration of the adenosine triphosphate (ATP)-sensitive potassium channel (K(ATP)) blockers, glibenclamide, or 5-hydroxydecanoate. MLA also was shown to attenuate myocardial stunning in dogs; however, its mechanism in this model remains unknown. Therefore the major aim of our study was to determine the dose-related effect of MLA to enhance contractile function in stunned myocardium and to determine the role of the K(ATP) channel in mediating its cardioprotective effect. To produce myocardial stunning, barbital-anesthetized dogs were subjected to five cycles of 5 min of left anterior descending (LAD) coronary artery occlusion interspersed with 10 min of reperfusion and finally followed by 2 h of reperfusion. Regional segment shortening (%SS) was determined by sonomicrometers implanted in the subendocardium of the ischemic region. Single intravenous doses of MLA in the range of 10-35 microg/kg given 24 h before ischemia resulted in an improvement in %SS over a 2-h reperfusion period. Similar to results obtained in the canine and rabbit infarct models, cardioprotection against stunning with MLA appears to require activation of K(ATP) channels during ischemia, because glibenclamide (50 microg/kg, 15 min before ischemia) completely blocked the effect of MLA to improve regional %SS during reperfusion. Cardioprotective doses of MLA were without effect on systemic hemodynamics, blood gases, and pH throughout the experiment. No treatment-related effects on regional myocardial blood flow were observed during ischemia or reperfusion. These results suggest that MLA improves %SS at doses of 10-35 microg/kg by an ATP-sensitive potassium channel-dependent process, and that MLA may mimic the antistunning effects observed during the second window of ischemic preconditioning.
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Affiliation(s)
- G T Elliott
- Pharmaceutical Development, Ribi ImmunoChem Research, Inc., Hamilton, Montana, USA
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24
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Wang P, Chen H, Qin H, Sankarapandi S, Becher MW, Wong PC, Zweier JL. Overexpression of human copper, zinc-superoxide dismutase (SOD1) prevents postischemic injury. Proc Natl Acad Sci U S A 1998; 95:4556-60. [PMID: 9539776 PMCID: PMC22528 DOI: 10.1073/pnas.95.8.4556] [Citation(s) in RCA: 182] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Superoxide and superoxide-derived oxidants have been hypothesized to be important mediators of postischemic injury. Whereas copper, zinc-superoxide dismutase, SOD1, efficiently dismutates superoxide, there has been controversy regarding whether increasing intracellular SOD1 expression would protect against or potentiate cellular injury. To determine whether increased SOD1 protects the heart from ischemia and reperfusion, studies were performed in a newly developed transgenic mouse model in which direct measurement of superoxide, contractile function, bioenergetics, and cell death could be performed. Transgenic mice with overexpression of human SOD1 were studied along with matched nontransgenic controls. Immunoblotting and immunohistology demonstrated that total SOD1 expression was increased 10-fold in hearts from transgenic mice compared with nontransgenic controls, with increased expression in both myocytes and endothelial cells. In nontransgenic hearts following 30 min of global ischemia a reperfusion-associated burst of superoxide generation was demonstrated by electron paramagnetic resonance spin trapping. However, in the transgenic hearts with overexpression of SOD1 the burst of superoxide generation was almost totally quenched, and this was accompanied by a 2-fold increase in the recovery of contractile function, a 2.2-fold decrease in infarct size, and a greatly improved recovery of high energy phosphates compared with that in nontransgenic controls. These results demonstrate that superoxide is an important mediator of postischemic injury and that increasing intracellular SOD1 dramatically protects the heart from this injury. Thus, increasing intracellular SOD1 expression may be a highly effective approach to decrease the cellular injury that occurs following reperfusion of ischemic tissues.
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Affiliation(s)
- P Wang
- Molecular and Cellular Biophysics Laboratories, Department of Medicine, Division of Cardiology and the Electron Paramagnetic Resonance Center, The Johns Hopkins University School of Medicine, Johns Hopkins Bayview Medical Center, Baltimore, MD 21224, USA
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