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Chase D, Eykyn TR, Shattock MJ, Chung YJ. Empagliflozin improves cardiac energetics during ischaemia/reperfusion by directly increasing cardiac ketone utilization. Cardiovasc Res 2023; 119:2672-2680. [PMID: 37819017 PMCID: PMC10730240 DOI: 10.1093/cvr/cvad157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 07/07/2023] [Accepted: 07/27/2023] [Indexed: 10/13/2023] Open
Abstract
AIMS Empagliflozin (EMPA), a potent inhibitor of the renal sodium-glucose cotransporter 2 and an effective treatment for Type 2 diabetes, has been shown to have cardioprotective effects, independent of improved glycaemic control. Several non-canonical mechanisms have been proposed to explain these cardiac effects, including increasing circulating ketone supply to the heart. This study aims to test whether EMPA directly alters cardiac ketone metabolism independent of supply. METHODS AND RESULTS The direct effects of EMPA on cardiac function and metabolomics were investigated in Langendorff rat heart perfused with buffer containing 5 mM glucose, 4 mM β-hydroxybutyrate (βHb) and 0.4 mM intralipid, subject to low flow ischaemia/reperfusion. Cardiac energetics were monitored in situ using 31P NMR spectroscopy. Steady-state 13C labelling was performed by switching 12C substrates for 13C1 glucose or 13C4 βHb and 13C incorporation into metabolites determined using 2D 1H-13C HSQC NMR spectroscopy. EMPA treatment improved left ventricular-developed pressure during ischaemia and reperfusion compared to vehicle-treated hearts. In EMPA-treated hearts, total adenosine triphosphate (ATP) and phosphocreatine (PCr) levels, and Gibbs free energy for ATP hydrolysis were significantly higher during ischaemia and reperfusion. EMPA treatment did not alter the incorporation of 13C from glucose into glycolytic products lactate or alanine neither during ischaemia nor reperfusion. In ischaemia, EMPA led to a decrease in 13C1 glucose incorporation and a concurrent increase in 13C4 βHb incorporation into tricarboxylic acid (TCA) cycle intermediates succinate, citrate, and glutamate. During reperfusion, the concentration of metabolites originating from 13C1 glucose was similar to vehicle but those originating from 13C4 βHb remained elevated in EMPA-treated hearts. CONCLUSION Our findings indicate that EMPA causes a switch in metabolism away from glucose oxidation towards increased ketone utilization in the rat heart, thereby improving function and energetics both during ischaemia and recovery during reperfusion. This preference of ketone utilization over glucose was observed under conditions of constant supply of substrate, suggesting that EMPA acts directly by modulating cardiac substrate preference, independent of substrate availability. The mechanisms underlying our findings are currently unknown, warranting further study.
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Affiliation(s)
- Dylan Chase
- British Heart Foundation Centre of Research Excellence, King’s College London, The Rayne Institute, 4th Floor, Lambeth Wing, St Thomas’ Hospital, London SE1 7EH, UK
| | - Thomas R Eykyn
- British Heart Foundation Centre of Research Excellence, King’s College London, The Rayne Institute, 4th Floor, Lambeth Wing, St Thomas’ Hospital, London SE1 7EH, UK
- School of Biomedical Engineering and Imaging Sciences, King’s College London, London SE1 7EH, UK
| | - Michael J Shattock
- British Heart Foundation Centre of Research Excellence, King’s College London, The Rayne Institute, 4th Floor, Lambeth Wing, St Thomas’ Hospital, London SE1 7EH, UK
| | - Yu Jin Chung
- British Heart Foundation Centre of Research Excellence, King’s College London, The Rayne Institute, 4th Floor, Lambeth Wing, St Thomas’ Hospital, London SE1 7EH, UK
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Pędzińska-Betiuk A, Weresa J, Schlicker E, Harasim-Symbor E, Toczek M, Kasacka I, Gajo B, Malinowska B. Chronic cannabidiol treatment reduces the carbachol-induced coronary constriction and left ventricular cardiomyocyte width of the isolated hypertensive rat heart. Toxicol Appl Pharmacol 2021; 411:115368. [PMID: 33338514 DOI: 10.1016/j.taap.2020.115368] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2020] [Revised: 11/29/2020] [Accepted: 12/13/2020] [Indexed: 11/29/2022]
Abstract
Cannabidiol (CBD) is suggested to possess cardioprotective properties. We examined the influence of chronic (10 mg/kg once daily for 2 weeks) CBD administration on heart structure (e.g. cardiomyocyte width) and function (e.g. stimulatory and inhibitory responses induced by β-adrenoceptor (isoprenaline) and muscarinic receptor (carbachol) activation, respectively). Experiments were performed on hearts and/or left atria isolated from spontaneously (SHR) and deoxycorticosterone (DOCA-salt) hypertensive rats; Wistar-Kyoto (WKY) and sham-operated rats (SHAM) served as the respective normotensive controls. CBD diminished the width of cardiomyocytes in left ventricle and reduced the carbachol-induced vasoconstriction of coronary arteries both in DOCA-salt and SHR. However, it failed to affect left ventricular hypertrophy and even aggravated the impaired positive and negative lusitropic effects elicited by isoprenaline and carbachol, respectively. In normotensive hearts CBD led to untoward structural and functional effects, which occurred only in WKY or SHAM or, like the decrease in β1-adrenoceptor density, in either control strain. In conclusion, due to its modest beneficial effect in hypertension and its adverse effects in normotensive hearts, caution should be taken when using CBD as a drug in therapy.
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MESH Headings
- Adrenergic beta-Agonists/pharmacology
- Animals
- Antihypertensive Agents/toxicity
- Cannabidiol/toxicity
- Carbachol/pharmacology
- Cell Size/drug effects
- Coronary Vessels/drug effects
- Coronary Vessels/physiopathology
- Disease Models, Animal
- Hypertension/complications
- Hypertension/drug therapy
- Hypertension/physiopathology
- Hypertrophy, Left Ventricular/etiology
- Hypertrophy, Left Ventricular/pathology
- Hypertrophy, Left Ventricular/physiopathology
- Isolated Heart Preparation
- Isoproterenol/pharmacology
- Myocytes, Cardiac/drug effects
- Myocytes, Cardiac/metabolism
- Myocytes, Cardiac/pathology
- Rats, Inbred SHR
- Rats, Inbred WKY
- Receptors, Adrenergic, beta-1/metabolism
- Receptors, Adrenergic, beta-2/metabolism
- Vasoconstriction/drug effects
- Vasoconstrictor Agents/pharmacology
- Ventricular Dysfunction, Left/etiology
- Ventricular Dysfunction, Left/pathology
- Ventricular Dysfunction, Left/physiopathology
- Ventricular Function, Left/drug effects
- Rats
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Affiliation(s)
- Anna Pędzińska-Betiuk
- Department of Experimental Physiology and Pathophysiology, Medical University of Białystok, Białystok, Poland.
| | - Jolanta Weresa
- Department of Experimental Physiology and Pathophysiology, Medical University of Białystok, Białystok, Poland
| | - Eberhard Schlicker
- Department of Pharmacology and Toxicology, University of Bonn, Bonn, Germany
| | - Ewa Harasim-Symbor
- Department of Physiology, Medical University of Białystok, Białystok, Poland
| | - Marek Toczek
- Department of Experimental Physiology and Pathophysiology, Medical University of Białystok, Białystok, Poland
| | - Irena Kasacka
- Department of Histology and Cytophysiology, Medical University of Białystok, Białystok, Poland
| | - Bernadetta Gajo
- Department of Experimental Physiology and Pathophysiology, Medical University of Białystok, Białystok, Poland
| | - Barbara Malinowska
- Department of Experimental Physiology and Pathophysiology, Medical University of Białystok, Białystok, Poland
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3
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Brook J, Kim MY, Koutsoftidis S, Pitcher D, Agha-Jaffar D, Sufi A, Jenkins C, Tzortzis K, Ma S, Jabbour RJ, Houston C, Handa BS, Li X, Chow JJ, Jothidasan A, Bristow P, Perkins J, Harding S, Bharath AA, Ng FS, Peters NS, Cantwell CD, Chowdhury RA. Development of a pro-arrhythmic ex vivo intact human and porcine model: cardiac electrophysiological changes associated with cellular uncoupling. Pflugers Arch 2020; 472:1435-1446. [PMID: 32870378 PMCID: PMC7476990 DOI: 10.1007/s00424-020-02446-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 06/11/2020] [Accepted: 08/06/2020] [Indexed: 01/19/2023]
Abstract
We describe a human and large animal Langendorff experimental apparatus for live electrophysiological studies and measure the electrophysiological changes due to gap junction uncoupling in human and porcine hearts. The resultant ex vivo intact human and porcine model can bridge the translational gap between smaller simple laboratory models and clinical research. In particular, electrophysiological models would benefit from the greater myocardial mass of a large heart due to its effects on far-field signal, electrode contact issues and motion artefacts, consequently more closely mimicking the clinical setting. Porcine (n = 9) and human (n = 4) donor hearts were perfused on a custom-designed Langendorff apparatus. Epicardial electrograms were collected at 16 sites across the left atrium and left ventricle. A total of 1 mM of carbenoxolone was administered at 5 ml/min to induce cellular uncoupling, and then recordings were repeated at the same sites. Changes in electrogram characteristics were analysed. We demonstrate the viability of a controlled ex vivo model of intact porcine and human hearts for electrophysiology with pharmacological modulation. Carbenoxolone reduces cellular coupling and changes contact electrogram features. The time from stimulus artefact to (-dV/dt)max increased between baseline and carbenoxolone (47.9 ± 4.1–67.2 ± 2.7 ms) indicating conduction slowing. The features with the largest percentage change between baseline and carbenoxolone were fractionation + 185.3%, endpoint amplitude − 106.9%, S-endpoint gradient + 54.9%, S point − 39.4%, RS ratio + 38.6% and (-dV/dt)max − 20.9%. The physiological relevance of this methodological tool is that it provides a model to further investigate pharmacologically induced pro-arrhythmic substrates.
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Affiliation(s)
- Joseph Brook
- Faculty of Medicine, National Heart and Lung Institute, Imperial College London, Hammersmith Campus, Du Cane Road, London, W12 0NN, UK
| | - Min-Young Kim
- Faculty of Medicine, National Heart and Lung Institute, Imperial College London, Hammersmith Campus, Du Cane Road, London, W12 0NN, UK
| | - Simos Koutsoftidis
- Faculty of Engineering, Imperial College London, South Kensington Campus, Exhibition Road, London, SW7 2AZ, UK
| | - David Pitcher
- Faculty of Medicine, National Heart and Lung Institute, Imperial College London, Hammersmith Campus, Du Cane Road, London, W12 0NN, UK
| | - Danya Agha-Jaffar
- Faculty of Medicine, National Heart and Lung Institute, Imperial College London, Hammersmith Campus, Du Cane Road, London, W12 0NN, UK
| | - Annam Sufi
- Faculty of Medicine, National Heart and Lung Institute, Imperial College London, Hammersmith Campus, Du Cane Road, London, W12 0NN, UK
| | - Catherine Jenkins
- Faculty of Medicine, National Heart and Lung Institute, Imperial College London, Hammersmith Campus, Du Cane Road, London, W12 0NN, UK
| | - Konstantinos Tzortzis
- Faculty of Medicine, National Heart and Lung Institute, Imperial College London, Hammersmith Campus, Du Cane Road, London, W12 0NN, UK
| | - Suofeiya Ma
- Faculty of Medicine, National Heart and Lung Institute, Imperial College London, Hammersmith Campus, Du Cane Road, London, W12 0NN, UK
| | - Richard J Jabbour
- Faculty of Medicine, National Heart and Lung Institute, Imperial College London, Hammersmith Campus, Du Cane Road, London, W12 0NN, UK
| | - Charles Houston
- Faculty of Medicine, National Heart and Lung Institute, Imperial College London, Hammersmith Campus, Du Cane Road, London, W12 0NN, UK
| | - Balvinder S Handa
- Faculty of Medicine, National Heart and Lung Institute, Imperial College London, Hammersmith Campus, Du Cane Road, London, W12 0NN, UK
| | - Xinyang Li
- Faculty of Medicine, National Heart and Lung Institute, Imperial College London, Hammersmith Campus, Du Cane Road, London, W12 0NN, UK
| | - Ji-Jian Chow
- Faculty of Medicine, National Heart and Lung Institute, Imperial College London, Hammersmith Campus, Du Cane Road, London, W12 0NN, UK
| | | | - Poppy Bristow
- Royal Veterinary College, University of London, Hawkshead Lane, Hertfordshire, AL97TA, UK
| | - Justin Perkins
- Royal Veterinary College, University of London, Hawkshead Lane, Hertfordshire, AL97TA, UK
| | - Sian Harding
- Faculty of Medicine, National Heart and Lung Institute, Imperial College London, Hammersmith Campus, Du Cane Road, London, W12 0NN, UK
| | - Anil A Bharath
- Faculty of Engineering, Imperial College London, South Kensington Campus, Exhibition Road, London, SW7 2AZ, UK
| | - Fu Siong Ng
- Faculty of Medicine, National Heart and Lung Institute, Imperial College London, Hammersmith Campus, Du Cane Road, London, W12 0NN, UK
| | - Nicholas S Peters
- Faculty of Medicine, National Heart and Lung Institute, Imperial College London, Hammersmith Campus, Du Cane Road, London, W12 0NN, UK
| | - Chris D Cantwell
- Faculty of Engineering, Imperial College London, South Kensington Campus, Exhibition Road, London, SW7 2AZ, UK
| | - Rasheda A Chowdhury
- Faculty of Medicine, National Heart and Lung Institute, Imperial College London, Hammersmith Campus, Du Cane Road, London, W12 0NN, UK.
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Kazemirad H, Kazerani HR. Cardioprotective effects of resveratrol following myocardial ischemia and reperfusion. Mol Biol Rep 2020; 47:5843-5850. [PMID: 32712855 DOI: 10.1007/s11033-020-05653-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Accepted: 07/08/2020] [Indexed: 01/24/2023]
Abstract
Resveratrol (RSV), a plant origin polyphenol, has shown beneficial cardiovascular effects. In this study, isolated hearts from male Wistar rats were studied using the Langendorff technique. Following 30 min stabilization, the hearts underwent 30 min global ischemia and 120 min reperfusion. The perfusion solution in the test group contained RSV (10 μM). Hemodynamics of the hearts, the markers of myocardial damage including creatine kinase-MB (CK-MB), lactate dehydrogenase (LDH), and troponin I were studied during the study. Furthermore, the infarct size and the markers of oxidative stress including catalase (CAT), superoxide dismutase (SOD), malondialdehyde (MDA), and glutathione peroxidase (GPX) were assayed in the homogenates of the hearts. The release of nitrite from the hearts and the occurrence of ventricular arrhythmias were also monitored throughout the experiment. Resveratrol caused a significant improvement in the restoration of the mechanical performance of the hearts following myocardial ischemia and reperfusion (MIR). Besides, the infarct size, CK-MB, LDH, and troponin I declined in the test group. Besides, the cardiac release of nitrite increased, and the redox status of the heart was improved as indicated by the levels of CAT, SOD, GPX, and MDA. Finally, the treatment caused significant decreases in the occurrences of single and salvo arrhythmias, ventricular tachycardia, and ventricular fibrillation. The current study suggests strong cardioprotective and antiarrhythmic effects for RSV following MIR.
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Affiliation(s)
- Hamideh Kazemirad
- Department of Physiology, The School of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad, PO Box: 91775 1793, Iran
| | - Hamid Reza Kazerani
- Department of Physiology, The School of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad, PO Box: 91775 1793, Iran.
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Uthman L, Nederlof R, Eerbeek O, Baartscheer A, Schumacher C, Buchholtz N, Hollmann MW, Coronel R, Weber NC, Zuurbier CJ. Delayed ischaemic contracture onset by empagliflozin associates with NHE1 inhibition and is dependent on insulin in isolated mouse hearts. Cardiovasc Res 2020; 115:1533-1545. [PMID: 30649212 DOI: 10.1093/cvr/cvz004] [Citation(s) in RCA: 63] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Accepted: 01/07/2019] [Indexed: 12/11/2022] Open
Abstract
AIMS Sodium glucose cotransporter 2 (SGLT2) inhibitors have sodium-hydrogen exchanger (NHE) inhibition properties in isolated cardiomyocytes, but it is unknown whether these properties extend to the intact heart during ischaemia-reperfusion (IR) conditions. NHE inhibitors as Cariporide delay time to onset of contracture (TOC) during ischaemia and reduce IR injury. We hypothesized that, in the ex vivo heart, Empagliflozin (Empa) mimics Cariporide during IR by delaying TOC and reducing IR injury. To facilitate translation to in vivo conditions with insulin present, effects were examined in the absence and presence of insulin. METHODS AND RESULTS Isolated C57Bl/6NCrl mouse hearts were subjected to 25 min I and 120 min R without and with 50 mU/L insulin. Without insulin, Empa and Cari delayed TOC by 100 and 129 s, respectively, yet only Cariporide reduced IR injury [infarct size (mean ± SEM in %) from 51 ± 6 to 34 ± 5]. Empa did not delay TOC in the presence of the NHE1 inhibitor Eniporide. Insulin perfusion increased tissue glycogen content at baseline (from 2 ± 2 µmol to 42 ± 1 µmol glycosyl units/g heart dry weight), amplified G6P and lactate accumulation at end-ischaemia, thereby decreased mtHKII and exacerbated IR injury. Under these conditions, Empa (1 µM) and Cariporide (10 µM) were without effect on TOC and IR injury. Empa and Cariporide both inhibited NHE activity, in isolated cardiomyocytes, independent of insulin. CONCLUSIONS In the absence of insulin, Empa and Cariporide strongly delayed the time to onset of contracture during ischaemia. In the presence of insulin, both Empa and Cari were without effect on IR, possibly because of severe ischaemic acidification. Insulin exacerbates IR injury through increased glycogen depletion during ischaemia and consequently mtHKII dissociation. The data suggest that also in the ex vivo intact heart Empa exerts direct cardiac effects by inhibiting NHE during ischaemia, but not during reperfusion.
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Affiliation(s)
- Laween Uthman
- Amsterdam UMC, University of Amsterdam, Laboratory of Experimental Intensive Care and Anesthesiology, Department of Anesthesiology, Amsterdam Cardiovascular Sciences, Amsterdam Infection & Immunity, Meibergdreef 9, AZ Amsterdam, The Netherlands
| | - Rianne Nederlof
- Institute of Cardiovascular Physiology, Heinrich-Heine University Düsseldorf, Düsseldorf, Universitätsstrasse 1, Düsseldorf, Germany
| | - Otto Eerbeek
- Amsterdam UMC, University of Amsterdam, Department of Medical Biology, Meibergdreef 9, AZ Amsterdam, The Netherlands
| | - Antonius Baartscheer
- Amsterdam UMC, University of Amsterdam, Clinical and Experimental Cardiology; Amsterdam Cardiovascular Sciences, Meibergdreef 9, AZ Amsterdam, The Netherlands
| | - Cees Schumacher
- Amsterdam UMC, University of Amsterdam, Clinical and Experimental Cardiology; Amsterdam Cardiovascular Sciences, Meibergdreef 9, AZ Amsterdam, The Netherlands
| | - Ninée Buchholtz
- Amsterdam UMC, University of Amsterdam, Laboratory of Experimental Intensive Care and Anesthesiology, Department of Anesthesiology, Amsterdam Cardiovascular Sciences, Amsterdam Infection & Immunity, Meibergdreef 9, AZ Amsterdam, The Netherlands
| | - Markus W Hollmann
- Amsterdam UMC, University of Amsterdam, Laboratory of Experimental Intensive Care and Anesthesiology, Department of Anesthesiology, Amsterdam Cardiovascular Sciences, Amsterdam Infection & Immunity, Meibergdreef 9, AZ Amsterdam, The Netherlands
| | - Ruben Coronel
- Amsterdam UMC, University of Amsterdam, Clinical and Experimental Cardiology; Amsterdam Cardiovascular Sciences, Meibergdreef 9, AZ Amsterdam, The Netherlands
| | - Nina C Weber
- Amsterdam UMC, University of Amsterdam, Laboratory of Experimental Intensive Care and Anesthesiology, Department of Anesthesiology, Amsterdam Cardiovascular Sciences, Amsterdam Infection & Immunity, Meibergdreef 9, AZ Amsterdam, The Netherlands
| | - Coert J Zuurbier
- Amsterdam UMC, University of Amsterdam, Laboratory of Experimental Intensive Care and Anesthesiology, Department of Anesthesiology, Amsterdam Cardiovascular Sciences, Amsterdam Infection & Immunity, Meibergdreef 9, AZ Amsterdam, The Netherlands
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Abdelgalil AA, Mohamed OY, Ahamad SR, Al-Jenoobi FI. The protective effect of losartan against sorafenib induced cardiotoxicity: Ex-vivo isolated heart and metabolites profiling studies in rat. Eur J Pharmacol 2020; 882:173229. [PMID: 32505666 DOI: 10.1016/j.ejphar.2020.173229] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 05/08/2020] [Accepted: 05/28/2020] [Indexed: 11/24/2022]
Abstract
Sorafenib, a tyrosine kinase inhibitor that is used in the treatment of hepatocellular and renal cell carcinoma, was reported to induce cardiotoxicity. This study aimed to investigate the potential cardioprotective effect of losartan against sorafenib-induced cardiotoxicity in rat. Sorafenib significantly reduced the left ventricular pressure, heart rate dp/dt max & dp/dt min (indexes of myocardial contractility and relaxation; respectively), and prolonged both the systolic and diastolic periods. Coadminstration of losartan significantly reversed the effects of sorafenib on heart rate, dp/dt max and dp/dt min. In addition, there was a tendency for losartan to reverse sorafenib reduction in left ventricular pressure and perfusion pressure but it did not reach statistical significance. A GC-MS non-targeted based metabolites profiling of rat plasma revealed elevated metaboites, including urea and fatty acids levels, associated with sorafenib induced cardiotoxicity. However, only glycine and lactic acid were statistically significant. Interestingly, losartan co-administration with sorafenib restored these changes, and resulted in a significantly reduced glycine, urea and some fatty acids levels namely; Cis-vaccenic acid, oleic acid, stearic acid and undecanoic acid. In addition, based on histology results, losartan coadminitration almost obviated sorafenib-induced changes in cardiac tissues. The study suggests that losartan has the potential to exert a protective effect against sorafenib-induced cardiotoxicity.
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Xia F, Jin Z, Lin T, Cai X, Pan L, Wang S, Cai Y, Chen H. Dexmedetomidine enhances tolerance to bupivacaine cardiotoxicity in the isolated rat hearts: alpha 2 adrenoceptors were not involved. BMC Pharmacol Toxicol 2019; 20:70. [PMID: 31753018 PMCID: PMC6873694 DOI: 10.1186/s40360-019-0371-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2019] [Accepted: 11/08/2019] [Indexed: 12/05/2022] Open
Abstract
Background Dexmedetomidine was proved to mitigate bupivacaine-induced cardiotoxicity but mechanism of this ability is still unclear. This study was designed to investigate the direct effects of dexmedetomidine on cardiotoxicity induced by bupivacaine on Langendorff rat heart preparation and the role of alpha 2 adrenoceptors in this process was explored. Methods Hearts of rat were isolated, mounted on a Langendorff system. Five experimental groups were assessed after 10 min Krebs-Henseleit buffer (KHB) infusions as follow: (1) Group Con, only KHB was perfused; (2) Group Dex, KHB was perfused for 5 min, then dexmedetomidine (10 nmol/L) was added; (3) Group Bupi, KHB was perfused for 25 min, then bupivacaine (50 μmol/L) was added; (4) Group Bupi + Dex, KHB was perfused for 5 min, then the dexmedetomidine (10 nmol/L) was added for 20 min, at last a mixture of KHB + dexmedetomidine + bupivacaine were perfused; (5) Group Bupi + Dex + Yoh, a combination of KHB + yohimbine (alpha 2 adrenoceptor antagonists, 1 μmol/L) was perfusion for 5 min, then dexmedetomidine (10 nmol/L) was added for 20 min, at last a mixture of KHB + yohimbine + dexmedetomidine + bupivacaine was perfused. The experimental perfusion was maintained for 35 min in group Con and group Dex, and the experimental perfusion was sustained until asystole in the other three groups. Results Compared with group Bupi, dexmedetomidine significantly increased the time to first arrhythmia (P < 0.001) and time to asystole (P < 0.001) in group Bupi + Dex. In addition, dexmedetomidine also significantly increased the time to 25, 50 and 75% reductions in heart rate (P < 0.001) and the time to 25, 50 and 75% reductions in rate-pressure product (P < 0.001) in group Bupi + Dex. Dexmedetomidine increased the cardiac tissue bupivacaine content when asystole (Bupi + Dex vs. Bupi, 58.5 ± 6.3 vs. 46.8 ± 5.6 nmol/g, P = 0.003). The benefit of dexmedetomidine on bupivacaine-induced cardiotoxicity were not eliminated by yohimbine. Conclusions Dexmedetomidine could delay the occurrence of bupivacaine-induced arrhythmia and asystole in the isolated rat hearts, but the alpha 2 adrenoceptors were not involved in this process.
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Affiliation(s)
- Fangfang Xia
- Department of Anesthesiology, The First Affiliated Hospital of Wenzhou Medical University, Shangcai village, Nanbaixiang town, Ouhai District, Wenzhou City, 325000, Zhejiang Province, China
| | - Zhousheng Jin
- Department of Anesthesiology, The First Affiliated Hospital of Wenzhou Medical University, Shangcai village, Nanbaixiang town, Ouhai District, Wenzhou City, 325000, Zhejiang Province, China
| | - Tingting Lin
- Department of Anesthesiology, The First Affiliated Hospital of Wenzhou Medical University, Shangcai village, Nanbaixiang town, Ouhai District, Wenzhou City, 325000, Zhejiang Province, China
| | - Xixi Cai
- Department of Anesthesiology, The First Affiliated Hospital of Wenzhou Medical University, Shangcai village, Nanbaixiang town, Ouhai District, Wenzhou City, 325000, Zhejiang Province, China
| | - Linmin Pan
- Department of Anesthesiology, The First Affiliated Hospital of Wenzhou Medical University, Shangcai village, Nanbaixiang town, Ouhai District, Wenzhou City, 325000, Zhejiang Province, China
| | - Shi Wang
- Department of Anesthesiology, The First Affiliated Hospital of Wenzhou Medical University, Shangcai village, Nanbaixiang town, Ouhai District, Wenzhou City, 325000, Zhejiang Province, China
| | - Yaoyao Cai
- Department of Anesthesiology, The First Affiliated Hospital of Wenzhou Medical University, Shangcai village, Nanbaixiang town, Ouhai District, Wenzhou City, 325000, Zhejiang Province, China
| | - Hongfei Chen
- Department of Anesthesiology, The First Affiliated Hospital of Wenzhou Medical University, Shangcai village, Nanbaixiang town, Ouhai District, Wenzhou City, 325000, Zhejiang Province, China.
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8
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Jeremic JN, Jakovljevic VL, Zivkovic VI, Srejovic IM, Bradic JV, Bolevich S, Nikolic Turnic TR, Mitrovic SL, Jovicic NU, Tyagi SC, Jeremic NS. The cardioprotective effects of diallyl trisulfide on diabetic rats with ex vivo induced ischemia/reperfusion injury. Mol Cell Biochem 2019; 460:151-164. [PMID: 31280436 DOI: 10.1007/s11010-019-03577-w] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Accepted: 06/21/2019] [Indexed: 12/22/2022]
Abstract
Diallyl trisulfide (DATS) is distinguished as the most potent polysulfide isolated from garlic. The aim of our study was to investigate effects of oral administration of DATS on healthy and diabetic rats, with special attention on heart function. Rats were randomly divided into four groups: CTRL (healthy rats), DATS (healthy rats treated with DATS), DM (diabetic rats), DM + DATS (diabetic rats treated with DATS). DATS (40 mg/kg of body weight) was administered every other day for 3 weeks, at the end of which rats underwent echocardiography, glycemic measurement and redox status assessment. Isolated rat hearts were subjected to 30 min global ischemia and 60 min reperfusion, after which heart tissue was counterstain with hematoxylin and eosin and cardiac Troponin T staining (cTnT), while expression of Bax, B cell lymphoma 2 (Bcl-2), caspase-3, caspase-9 and superoxide dismutase-2 were examined in the left ventricle. DATS treatment significantly reduced blood glucose levels of diabetic rats, and improved cardiac function recovery, diminished oxidation status, attenuated cardiac remodeling and inhibited myocardial apoptosis in healthy and diabetic rats. DATS treatment causes promising cardioprotective effects on ex vivo-induced ischemia/reperfusion (I/R) injury in diabetic and healthy rat heart probably mediated by inhibited myocardial apoptosis. Moreover, appropriate DATS consumption may provide potential co-therapy or prevention of hyperglycemia and various cardiac complications in rats with DM.
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Affiliation(s)
- Jovana N Jeremic
- Department of Pharmacy, Faculty of Medical Sciences, University of Kragujevac, Svetozara Markovica 69, Kragujevac, 34 000, Serbia
| | - Vladimir Lj Jakovljevic
- Department of Physiology, Faculty of Medical Sciences, University of Kragujevac, Svetozara Markovica 69, Kragujevac, 34 000, Serbia
- Department of Human Pathology, 1st Moscow State Medical, University IM Sechenov, Trubetskaya Street 8, Moscow, Russia, 119991
| | - Vladimir I Zivkovic
- Department of Physiology, Faculty of Medical Sciences, University of Kragujevac, Svetozara Markovica 69, Kragujevac, 34 000, Serbia
| | - Ivan M Srejovic
- Department of Physiology, Faculty of Medical Sciences, University of Kragujevac, Svetozara Markovica 69, Kragujevac, 34 000, Serbia
| | - Jovana V Bradic
- Department of Pharmacy, Faculty of Medical Sciences, University of Kragujevac, Svetozara Markovica 69, Kragujevac, 34 000, Serbia
| | - Sergey Bolevich
- Department of Human Pathology, 1st Moscow State Medical, University IM Sechenov, Trubetskaya Street 8, Moscow, Russia, 119991
| | - Tamara R Nikolic Turnic
- Department of Pharmacy, Faculty of Medical Sciences, University of Kragujevac, Svetozara Markovica 69, Kragujevac, 34 000, Serbia
| | - Slobodanka Lj Mitrovic
- Department of Pathology, Faculty of Medical Sciences, University of Kragujevac, Svetozara Markovica 69, Kragujevac, 34 000, Serbia
| | - Nemanja U Jovicic
- Department of Histology and Embryology, Faculty of Medical Sciences, University of Kragujevac, Svetozara Markovica 69, Kragujevac, 34 000, Serbia
| | - Suresh C Tyagi
- Department of Physiology, School of Medicine, University of Louisville, 500 S Preston Street, Louisville, KY, 40202, USA
| | - Nevena S Jeremic
- Department of Pharmacy, Faculty of Medical Sciences, University of Kragujevac, Svetozara Markovica 69, Kragujevac, 34 000, Serbia.
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9
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Okoshi K, Cezar MDM, Polin MAM, Paladino JR, Martinez PF, Oliveira SA, Lima ARR, Damatto RL, Paiva SAR, Zornoff LAM, Okoshi MP. Influence of intermittent fasting on myocardial infarction-induced cardiac remodeling. BMC Cardiovasc Disord 2019; 19:126. [PMID: 31138145 PMCID: PMC6540428 DOI: 10.1186/s12872-019-1113-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Accepted: 05/20/2019] [Indexed: 02/07/2023] Open
Abstract
Background Information on the role of intermittent fasting (IF) on pathologic cardiac remodeling is scarce. We compared the effects of IF before and after myocardial infarction (MI) on rat cardiac remodeling and survival. Methods Wistar rats were intermittently fasted (food available every other day) or fed ad libitum for 12 weeks and then divided into three groups: AL – fed ad libitum; AL/IF - fed AL before MI and IF after MI; and IF – fed IF before and after MI. Echocardiogram was performed before MI and 2 and 12 weeks after surgery. Isolated hearts were evaluated in Langendorff preparations. Results Before surgery, body weight (BW) was lower in IF than AL. Final BW was lower in AL/IF and IF than AL. Perioperative mortality did not change between AL (31.3%) and IF (27.3%). Total mortality was lower in IF than AL. Before surgery, echocardiographic parameters did not differ between groups. Two weeks after surgery, MI size did not differ between groups. Twelve weeks after MI, left ventricular (LV) diastolic posterior wall thickness was lower in AL/IF and IF than AL. The percentage of variation of echocardiographic parameters between twelve and two weeks showed that MI size decreased in all groups and the reduction was higher in IF than AL/IF. In Langendorff preparations, LV volume at zero end-diastolic pressure (V0; AL: 0.41 ± 0.05; AL/IF: 0.34 ± 0.06; IF: 0.28 ± 0.05 mL) and at 25 mmHg end-diastolic pressure (V25; AL: 0.61 ± 0.05; AL/IF: 0.54 ± 0.07; IF: 0.44 ± 0.06 mL) was lower in AL/IF and IF than AL and V25 was lower in IF than AL/IF. V0/BW ratio was lower in IF than AL and LV weight/V0 ratio was higher in IF than AL. Myocyte diameter was lower in AL/IF and IF than AL (AL: 17.3 ± 1.70; AL/IF: 15.1 ± 2.21; IF: 13.4 ± 1.49 μm). Myocardial hydroxyproline concentration and gene expression of ANP, Serca 2a, and α- and β-myosin heavy chain did not differ between groups. Conclusion Intermittent fasting initiated before or after MI reduces myocyte hypertrophy and LV dilation. Myocardial fibrosis and fetal gene expression are not modulated by feeding regimens. Benefit is more evident when intermittent fasting is initiated before rather than after MI.
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Affiliation(s)
- K Okoshi
- Internal Medicine Department, Botucatu Medical School, Sao Paulo State University, UNESP, Botucatu, SP, Brazil.,Departamento de Clinica Medica, Faculdade de Medicina de Botucatu, UNESP, Rubiao Junior, S/N. CEP 18618-687, Botucatu, SP, Brazil
| | - M D M Cezar
- Internal Medicine Department, Botucatu Medical School, Sao Paulo State University, UNESP, Botucatu, SP, Brazil.,Departamento de Clinica Medica, Faculdade de Medicina de Botucatu, UNESP, Rubiao Junior, S/N. CEP 18618-687, Botucatu, SP, Brazil.,Itapeva Social and Agrarian Sciences College, FAIT, Itapeva, SP, Brazil
| | - M A M Polin
- Internal Medicine Department, Botucatu Medical School, Sao Paulo State University, UNESP, Botucatu, SP, Brazil.,Departamento de Clinica Medica, Faculdade de Medicina de Botucatu, UNESP, Rubiao Junior, S/N. CEP 18618-687, Botucatu, SP, Brazil
| | - J R Paladino
- Internal Medicine Department, Botucatu Medical School, Sao Paulo State University, UNESP, Botucatu, SP, Brazil.,Departamento de Clinica Medica, Faculdade de Medicina de Botucatu, UNESP, Rubiao Junior, S/N. CEP 18618-687, Botucatu, SP, Brazil
| | - P F Martinez
- Federal University of Mato Grosso do Sul, Cidade Universitária, Av. Costa e Silva - Pioneiros, Campo Grande, MS, 79070-900, Brazil
| | - S A Oliveira
- Federal University of Mato Grosso do Sul, Cidade Universitária, Av. Costa e Silva - Pioneiros, Campo Grande, MS, 79070-900, Brazil
| | - A R R Lima
- Internal Medicine Department, Botucatu Medical School, Sao Paulo State University, UNESP, Botucatu, SP, Brazil.,Departamento de Clinica Medica, Faculdade de Medicina de Botucatu, UNESP, Rubiao Junior, S/N. CEP 18618-687, Botucatu, SP, Brazil
| | - R L Damatto
- Internal Medicine Department, Botucatu Medical School, Sao Paulo State University, UNESP, Botucatu, SP, Brazil.,Departamento de Clinica Medica, Faculdade de Medicina de Botucatu, UNESP, Rubiao Junior, S/N. CEP 18618-687, Botucatu, SP, Brazil.,Itapeva Social and Agrarian Sciences College, FAIT, Itapeva, SP, Brazil
| | - S A R Paiva
- Internal Medicine Department, Botucatu Medical School, Sao Paulo State University, UNESP, Botucatu, SP, Brazil.,Departamento de Clinica Medica, Faculdade de Medicina de Botucatu, UNESP, Rubiao Junior, S/N. CEP 18618-687, Botucatu, SP, Brazil
| | - L A M Zornoff
- Internal Medicine Department, Botucatu Medical School, Sao Paulo State University, UNESP, Botucatu, SP, Brazil.,Departamento de Clinica Medica, Faculdade de Medicina de Botucatu, UNESP, Rubiao Junior, S/N. CEP 18618-687, Botucatu, SP, Brazil
| | - M P Okoshi
- Internal Medicine Department, Botucatu Medical School, Sao Paulo State University, UNESP, Botucatu, SP, Brazil. .,Departamento de Clinica Medica, Faculdade de Medicina de Botucatu, UNESP, Rubiao Junior, S/N. CEP 18618-687, Botucatu, SP, Brazil.
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10
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Howard BT, Iaizzo PA. Induced functional modulations of isolated large mammalian hearts. Pflugers Arch 2019; 471:1095-1101. [PMID: 31123804 DOI: 10.1007/s00424-019-02277-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Revised: 02/25/2019] [Accepted: 04/16/2019] [Indexed: 11/25/2022]
Abstract
In this study we used Visible Heart® methodologies featuring cyclic temperature modulation of porcine hearts in order to establish characteristic temperature responses. This isolated and perfused model is a more predictable and modifiable analog for human heart preservation and isolates the response of the cardiac tissue. We comprehensively monitored isolated porcine hearts undergoing temperature change and demonstrated optimization of isolated cardiac function under mild hypothermia. We tracked metrics of cardiac function as continuous variables during temperature changes (~ 31 to 39 °C), eliciting a well-defined reduction in metabolic demand and in heart rate modulation. Optimization of function appeared to occur around 34.7 ± 0.9 °C (n = 13). Cardiac response was further investigated in the presence of active pacing in order to assess pacing capture and the heart's functional response without a means of regulating rate. Our results may have direct clinical implications for emerging heart preservation methods prior to transplantation, as well as benefits for investigators using isolated heart models for preclinical device testing. Clinically, this porcine model is a basis for finding new ways to extend the window of viability for transplantable organs, thereby restoring or improving graft function and potentially enhancing recipient outcomes.
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Affiliation(s)
- Brian T Howard
- Medtronic Inc., 8200 Coral Sea St NE, Mounds View, MN, 55112, USA
| | - Paul A Iaizzo
- Department of Surgery, University of Minnesota, 420 Delaware St. SE, B172 Mayo, MMC 195, Minneapolis, MN, 55455, USA.
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11
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Zhang Q, Ma JH, Li H, Wei XH, Zheng J, Li G, Wang CY, Wu Y, He QH, Wu L. Increase in CO 2 levels by upregulating late sodium current is proarrhythmic in the heart. Heart Rhythm 2019; 16:1098-106. [PMID: 30710739 DOI: 10.1016/j.hrthm.2019.01.029] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Indexed: 12/19/2022]
Abstract
BACKGROUND Increased CO2 levels in the general circulation and/or in the myocardium are common under pathologic conditions. OBJECTIVE The purpose of this study was to test the hypothesis that an increase in CO2 levels, and not just the subsequent extra- or intracellular acidosis, would augment late sodium current (INa,L) and contribute to arrhythmogenesis in hearts with reduced repolarization reserve. METHODS Monophasic action potential durations at 90% completion of repolarization (MAPD90) from isolated rabbit hearts, INa,L, and extra- (pHo) and intracellular pH (pHi) values from cardiomyocytes using the whole-cell patch-clamp techniques and 2',7'-bis-(2-carboxyethyl)-5-(and-6)-carboxyfluorescein, acetoxymethyl ester (BCECF-AM), respectively, were measured. RESULTS Increasing CO2 levels from 5% to 10% and 20% and administration of 1 nM sea anemone toxin (ATX)-II increased INa,L and prolonged both epicardial and endocardial MAPD90 (n = 7 and 10, respectively) without causing arrhythmic activities. Compared to 5% CO2, 10% and 20% CO2 decreased pHo and pHi in hearts treated with 1 nM ATX-II, caused greater prolongation of MAPD90, and elicited ventricular tachycardias. Increasing CO2 levels from 5% to 10% and 20% with pHo maintained at 7.4 produced smaller changes in pHi (P <.05) but similar increases in INa,L, prolongation of MAPD90, and incidence of ventricular tachycardias (n = 8). Inhibition of INa,L reversed the increase in INa,L, suppressed MAPD90 prolongations, and ventricular tachycardias induced by 20% CO2. Increased phospho-calmodulin-dependent protein kinase II-δ (CaMKIIδ) and phospho-NaV1.5 protein levels in hearts treated with 20% CO2 was attenuated by eleclazine. CONCLUSION Increased CO2 levels enhance INa,L and are proarrhythmic factors in hearts with reduced repolarization reserve, possibly via mechanisms related to phosphorylation of CaMKIIδ and NaV1.5.
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12
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Vesely P, Stracina T, Hlavacova M, Halamek J, Kolarova J, Olejnickova V, Mrkvicova V, Paulova H, Novakova M. Haloperidol affects coupling between QT and RR intervals in guinea pig isolated heart. J Pharmacol Sci 2018; 139:23-28. [PMID: 30528680 DOI: 10.1016/j.jphs.2018.11.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 11/08/2018] [Accepted: 11/12/2018] [Indexed: 11/25/2022] Open
Abstract
Prolonged QT interval is an independent risk factor for development of ventricular arrhythmias. Haloperidol is one of the drugs inducing QT prolongation. Previous studies showed that haloperidol affects not only QT duration but also heart rate (RR interval). The present work focused on relationship between QT and RR and its changes under acute and chronic haloperidol administration. The study included 14 male guinea pigs divided into control and haloperidol-treated group. After 21-days administration of haloperidol or vehiculum, electrograms in isolated hearts were recorded. QT/RR and dQT/dRR coupling were calculated. Chronic haloperidol administration significantly decreases the coupling between QT and RR. Acute haloperidol exposure significantly decreases the dQT/dRR coupling in both treated and untreated guinea pig hearts. Flatter QT/RR relationship reveals a lack of QT adaptation to increased heart rate. It should be emphasized that in such situation ECG recording will not show significant QT prolongation evaluated according to clinical rules. However, if QT interval does not adapt to increased heart rate sufficiently, the risk of ventricular arrhythmias may be increased despite practically normal QT interval length. The results are supported by findings in biochemical analyses, which proved eligibility of the used model.
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Affiliation(s)
- Petr Vesely
- International Clinical Research Center, St. Anne's Faculty Hospital, Brno, Czech Republic; Department of Biomedical Engineering, Brno University of Technology, Brno, Czech Republic
| | - Tibor Stracina
- Department of Physiology, Faculty of Medicine, Masaryk University, Brno, Czech Republic.
| | - Miroslava Hlavacova
- Department of Biochemistry, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Josef Halamek
- Institute of Scientific Instruments, Academy of Sciences, Brno, Czech Republic
| | - Jana Kolarova
- Department of Biomedical Engineering, Brno University of Technology, Brno, Czech Republic
| | - Veronika Olejnickova
- Department of Physiology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Veronika Mrkvicova
- Department of Sports Medicine and Rehabilitation (KFDR), St. Anne's Faculty Hospital, Masaryk University, Brno, Czech Republic; Department of Public Health, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Hana Paulova
- Department of Biochemistry, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Marie Novakova
- International Clinical Research Center, St. Anne's Faculty Hospital, Brno, Czech Republic; Department of Physiology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
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13
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Haghi J, Eteraf-Oskouei T, Najafi M. Effects of Postconditioning with Fructose on Arrhythmias and the Size of Infarct Caused by Global Ischemia and Reperfusion in Isolated Rat Heart. Adv Pharm Bull 2018; 8:57-62. [PMID: 29670839 PMCID: PMC5896396 DOI: 10.15171/apb.2018.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Revised: 12/28/2017] [Accepted: 01/01/2018] [Indexed: 12/28/2022] Open
Abstract
Purpose: In the present study, postconditioning effect of fructose against ischemia/reperfusion (I/R)-induced arrhythmias and infarct size were investigated in isolated rat heart. Methods: The isolated hearts were divided into 7 groups, mounted on a Langendorff apparatus at constant pressure then subjected to 30 min zero flow global ischemia followed by 120 min reperfusion. In the control group, normal Krebs–Henseleit (K/H) solution was perfused into the hearts throughout the experiment. In two separate sets of experiments, the treatment groups received 12, 24 and 48 mM of fructose with/without normal glucose in K/H solution for 20 min at the beginning of reperfusion. Cardiac arrhythmias including number of ventricular tachycardia (VT), total ventricular ectopic beats, incidence and duration of VT, reversible and irreversible ventricular fibrillation were recorded and analyzed during the first 30 min of reperfusion. Computerized planimetry method was used to determine volume and percentage of infarct size. Results: Administration of fructose as a postconditioning agent clearly reduced volume and percentage of infarct size in the all treatment groups. The effect was statistically significant especially in the hearts that treated by fructose plus glucose (P<0.05). However, fructose alone or its co-administration with glucose had no significant inhibitory effect against reperfusion arrhythmias. Conclusion: The results showed that perfusion of high concentration of fructose alone or coincident with glucose in globally ischemic-reperfused isolated rat hearts can reduce infarct size without inhibitory effect against reperfusion arrhythmias. Probably, fructose by providing adequate ATP for cardiac functions may inhibit necrosis and death of cardiomyocytes during I/R.
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Affiliation(s)
- Jila Haghi
- Student Research Committee, Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Tahereh Eteraf-Oskouei
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Moslem Najafi
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
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14
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Motayagheni N. Modified Langendorff technique for mouse heart cannulation: Improved heart quality and decreased risk of ischemia. MethodsX 2017; 4:508-512. [PMID: 29204375 PMCID: PMC5704101 DOI: 10.1016/j.mex.2017.11.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Accepted: 11/03/2017] [Indexed: 02/07/2023] Open
Abstract
Oscar Langendorff introduced the first method for isolating a heart with contractile activity in 1895. Since then, the Langendorff method has remained a powerful technique in cardiac research and has led to major advances in medicine. The primary goal of the Langendorff method is to provide an isolated heart with oxygen and metabolites via a cannula inserted into the aorta. The Langendorff heart is a complex in vitro technique used primarily in pharmacological and physiological research that allows the evaluation of multiple cardiac hemodynamic parameters including, but not limited to, contractility and heart rate. This article will first provide a brief background of the Langendorff method as well as details regarding organ isolation. Finally, the article will discuss the benefits of a new technique for hanging the isolated heart aorta and the benefits of this technique over traditional methods.
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Affiliation(s)
- Negar Motayagheni
- Wake Forest Institute for Regenerative Medicine, 391 Technology Way, Medical Center Boulevard, Winston-Salem, NC 27157, USA
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15
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Ferreira de Mattos G, Costa C, Savio F, Alonso M, Nicolson GL. Lead poisoning: acute exposure of the heart to lead ions promotes changes in cardiac function and Cav1.2 ion channels. Biophys Rev 2017; 9:807-25. [PMID: 28836190 DOI: 10.1007/s12551-017-0303-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Accepted: 07/28/2017] [Indexed: 01/02/2023] Open
Abstract
Lead ions (Pb2+) possess characteristics similar to Ca2+. Because of this and its redox capabilities, lead causes different toxic effects. The neurotoxic effects have been well documented; however, the toxic effects on cardiac tissues remain allusive. We utilized isolated guinea pig hearts and measured the effects of Pb2+ on their contractility and excitability. Acute exposure to extracellular Pb2+ had a negative inotropic effect and increased diastolic tension. The speed of contraction and relaxation were affected, though the effects were more dramatic on the speed of contraction. Excitability was also altered. Heart beat frequency increased and later diminished after lead ion exposure. Pro-arrhytmic events, such as early after-depolarization and a reduction of the action potential plateau, were also observed. In isolated cardiomyocytes and tsA 201 cells, extracellular lead blocked currents through Cav1.2 channels, diminished their activation, and enhanced their fast inactivation, negatively affecting their gating currents. Thus, Pb2+ was cardiotoxic and reduced cardiac contractility, making the heart prone to arrhythmias. This was due, in part, to Pb2+ effects on the Cav1.2 channels; however, other channels, transporters or pathways may also be involved. Acute cardiotoxic effects were observed at Pb2+ concentrations achievable during acute lead poisoning. The results suggest how Cav1.2 gating can be affected by divalent cations, such as Pb2, and also suggest a more thorough evaluation of heart function in individuals affected by lead poisoning.
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16
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Ronzhina M, Olejnickova V, Stracina T, Novakova M, Janousek O, Hejc J, Kolarova J, Hlavacova M, Paulova H. Effect of increased left ventricle mass on ischemia assessment in electrocardiographic signals: rabbit isolated heart study. BMC Cardiovasc Disord 2017; 17:216. [PMID: 28778146 PMCID: PMC5544990 DOI: 10.1186/s12872-017-0652-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Accepted: 07/28/2017] [Indexed: 01/19/2023] Open
Abstract
Background Detailed quantitative analysis of the effect of left ventricle (LV) hypertrophy on myocardial ischemia manifestation in ECG is still missing. The associations between both phenomena can be studied in animal models. In this study, rabbit isolated hearts with spontaneously increased LV mass were used to evaluate the effect of such LV alteration on ischemia detection criteria and performance. Methods Electrophysiological effects of increased LV mass were evaluated on sixteen New Zealand rabbit isolated hearts under non-ischemic and ischemic conditions by analysis of various electrogram (EG) parameters. To reveal hearts with increased LV mass, LV weight/heart weight ratio was proposed. Standard paired and unpaired statistical tests and receiver operating characteristics analysis were used to compare data derived from different groups of animals, monitor EG parameters during global ischemia and evaluate their ability to discriminate between unchanged and increased LV as well as non-ischemic and ischemic state. Results Successful evaluation of both increased LV mass and ischemia is lead-dependent. Particularly, maximal deviation of QRS and area under QRS associated with anterolateral heart wall respond significantly to even early phase (the 1st-3rd min) of ischemia. Besides ischemia, these parameters reflect increased LV mass as well (with sensitivity reaching approx. 80%). However, the sensitivity of the parameters to both phenomena may lead to misinterpretations, when inappropriate criteria for ischemia detection are selected. Particularly, use of cut-off-based criteria defined from control group for ischemia detection in hearts with increased LV mass may result in dramatic reduction (approx. 15%) of detection specificity due to increased number of false positives. Nevertheless, criteria adjusted to particular experimental group allow achieving ischemia detection sensitivity of 89–100% and specificity of 94–100%, respectively. Conclusions It was shown that response of the heart to myocardial ischemia can be successfully evaluated only when taking into account heart-related factors (such as LV mass) and other methodological aspects (such as recording electrodes position, selected EG parameters, cut-off criteria, etc.). Results of this study might be helpful for developing new clinical diagnostic strategies in order to improve myocardial ischemia detection in patients with LV hypertrophy.
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Affiliation(s)
- Marina Ronzhina
- Department of Biomedical Engineering, Faculty of Electrical Engineering and Communication, Brno University of Technology, Technická 12, 616 00, Brno, Czech Republic.
| | - Veronika Olejnickova
- Department of Physiology, Faculty of Medicine, Masaryk University, Kamenice 753/5, 625 00, Brno, Czech Republic.,Institute of Anatomy, First Faculty of Medicine, Charles University in Prague, U Nemocnice 3, 128 00, Prague, Czech Republic.,Institute of Physiology, Czech Academy of Sciences, Vídeňská 1083, 142 20, Praque, Czech Republic
| | - Tibor Stracina
- Department of Physiology, Faculty of Medicine, Masaryk University, Kamenice 753/5, 625 00, Brno, Czech Republic
| | - Marie Novakova
- Department of Physiology, Faculty of Medicine, Masaryk University, Kamenice 753/5, 625 00, Brno, Czech Republic.,International Clinical Research Center, St. Anne's University Hospital Brno, Pekářská 53, 656 91, Brno, Czech Republic
| | - Oto Janousek
- Department of Biomedical Engineering, Faculty of Electrical Engineering and Communication, Brno University of Technology, Technická 12, 616 00, Brno, Czech Republic
| | - Jakub Hejc
- Department of Biomedical Engineering, Faculty of Electrical Engineering and Communication, Brno University of Technology, Technická 12, 616 00, Brno, Czech Republic
| | - Jana Kolarova
- Department of Biomedical Engineering, Faculty of Electrical Engineering and Communication, Brno University of Technology, Technická 12, 616 00, Brno, Czech Republic
| | - Miroslava Hlavacova
- Department of Biochemistry, Faculty of Medicine, Masaryk University, Kamenice 753/5, 625 00, Brno, Czech Republic
| | - Hana Paulova
- Department of Biochemistry, Faculty of Medicine, Masaryk University, Kamenice 753/5, 625 00, Brno, Czech Republic
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Ristic P, Srejovic I, Nikolic T, Stojic I, Ristic D, Zivkovic V, Jakovljevic VL. The effects of zofenopril on cardiac function and pro-oxidative parameters in the streptozotocin-induced diabetic rat heart. Mol Cell Biochem 2017; 426:183-93. [PMID: 27882442 DOI: 10.1007/s11010-016-2890-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Accepted: 11/15/2016] [Indexed: 01/01/2023]
Abstract
Diabetes mellitus is a chronic condition that continues to increase in both incidence and prevalence. Renin-Angiotensin-Aldosterone System is one of the main modulators of chronic hyperglycaemia and, thus, its influence on tissues. Hyperglycaemia-induced oxidative stress is an important factor in diabetic cardiomyopathy. The present study was carried out on 24 adult male Wistar albino rats (8-week-old and with body masses of 190 ± 10 g). We evaluated the influence of acute administration of zofenopril on ex vivo myocardial function from rats with streptozotocin-induced diabetes mellitus, with a special emphasis on cardiodynamic and oxidative stress parameters in diabetic rat hearts. Rats were divided randomly into two groups (12 animals per group): control non-diabetic animals (C) were healthy rats perfused with 1.5 µM of zofenopril, and STZ-treated diabetic animals (DM) were diabetic animals perfused with 1.5 µM of zofenopril 4 weeks after the induction of diabetes. Our results demonstrated that diabetic rats are characterized by a depressed cardiac performance and that oxidative markers are related to alterations in cardiac function in rats with 4 weeks of STZ-induced diabetes. Additionally, the use of zofenopril as a monotherapy slightly diminished cardiac damage induced by chronic hyperglycaemia. However, long-term follow-up intervention trials are necessary to fully demonstrate the benefit of zofenopril in this context. A challenge for future investigations will be to identify the effects of chronic administration or combination therapy with angiotensin-converting enzyme inhibitors in various models of diabetes.
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18
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Imani A, Khansari M, Azizi Y, Rakhshan K, Faghihi M. Stimulation of Oxytocin Receptor during Early Reperfusion Period Protects the Heart against Ischemia/Reperfusion Injury: the Role of Mitochondrial ATP-Sensitive Potassium Channel, Nitric Oxide, and Prostaglandins. Acta Med Iran 2015; 53:491-500. [PMID: 26545994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/06/2015] [Indexed: 06/05/2023] Open
Abstract
Postconditioning is a simple and safe strategy for cardioprotection and infarct size limitation. Our previous study showed that oxytocin (OT) exerts postconditioning effect on ischemic/reperfused isolated rat heart. The aim of this study was to investigate the involvement of OT receptor, mitochondrial ATP-sensitive potassium channel (mKATP), nitric oxide (NO) and cyclooxygenase (COX) pathways in OT postconditioning. Isolated rat hearts were divided into10 groups and underwent 30 min of regional ischemia followed by 120 min of reperfusion (n =6). In I/R (ischemia/reperfusion) group, ischemia and reperfusion were induced without any treatment. In OT group, oxytocin was perfused 5 min prior to beginning of reperfusion for 25 min. In groups 3-6, atosiban (oxytocin receptor blocker), L-NAME (N-Nitro-L-Arginine Methyl Ester, non-specific nitric oxide synthase inhibitor), 5-HD (5-hydroxydecanoate, mKATP inhibitor) and indomethacin (cyclooxygenase inhibitor) were infused prior to oxytocin administration. In others, the mentioned inhibitors were perfused prior to ischemia without oxytocin infusion. Infarct size, ventricular hemodynamic, coronary effluent, malondialdehyde (MDA) and lactate dehydrogenase (LDH) were measured at the end of reperfusion. OT perfusion significantly reduced infarct size, MDA and LDH in comparison with IR group. Atosiban, 5HD, L-NAME and indomethacin abolished the postconditioning effect of OT. Perfusion of the inhibitors alone prior to ischemia had no effect on infarct size, hemodynamic parameters, coronary effluent and biochemical markers as compared with I/R group. In conclusion, this study indicates that postconditioning effects of OT are mediated by activation of mKATP and production of NO and Prostaglandins (PGs).
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Affiliation(s)
- Alireza Imani
- 1Department of Physiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Maryam Khansari
- 1Department of Physiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Yaser Azizi
- Department of Physiology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Kamran Rakhshan
- 1Department of Physiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Mahdieh Faghihi
- 1Department of Physiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
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Yang Z, Eggen MD, Marquard KR, Asleson AJ, McVenes RD, Iaizzo PA. Direct visualization of an atrial transseptal left ventricular endocardial lead implantation within an isolated heart. HeartRhythm Case Rep 2015; 1:107-109. [PMID: 28507900 PMCID: PMC5426419 DOI: 10.1016/j.hrcr.2015.01.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
| | | | | | | | | | - Paul A Iaizzo
- Departments of Surgery, Biomedical Engineering, and Integrative Biology & Physiology, and the Institute for Engineering in Medicine, University of Minnesota, Minneapolis, Minnesota
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Noorbakhsh MF, Arab HA, Kazerani HR. Liver ischemia preconditions the heart against ischemia-reperfusion arrhythmias. Iran J Basic Med Sci 2015; 18:80-8. [PMID: 25810880 PMCID: PMC4366748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Accepted: 09/27/2014] [Indexed: 10/28/2022]
Abstract
OBJECTIVES This study aimed to examine the hypothesis that an antiarrhythmic effect might be obtained by ischemic preconditioning of the liver, and also to characterize the potential underlying mechanisms. MATERIALS AND METHODS Male Wistar rats were anesthetized by thiopental sodium (50 mg/kg, IP) followed by IV injection of heparin (250 IU). Remote ischemic preconditioning (RIPC) was induced by 3 cycles of 5 min liver ischemia followed by 5 min of reperfusion. The hearts were excised within 5 min after the final cycle of preconditioning and perfused using Langendorff's system. The isolated perfused hearts were subjected to 30 min global ischemia followed by 90 min reperfusion. The myocardial arrhythmias induced by ischemia- reperfusion (I/R) were determined in accordance with the guidelines of Lambeth Conventions. The potential role of KATP channels on RIPC was assessed by injection of glibenclamide (nonselective KATP blocker) or 5-hydroxydecanoate (mitochondrial KATP blocker) on rats 30 and 15 min before induction of RIPC in the liver, respectively. RESULTS Hepatic remote preconditioning of the heart significantly (P<0.0001) prevented the incidence of myocardial arrhythmias induced by I/R in the perfused hearts (5.33±1.54 vs. 32.33±6.44,). However, the protective effects of remote preconditioning was significantly (P<0.01) abolished by the KATP blocker, glibenclamide (25.5±4.9 vs. 5.33±1.54,). CONCLUSION Hepatic RIPC may prevent the arrhythmias induced by I/R in the isolated perfused hearts via KATP channels.
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Affiliation(s)
| | - Hossein-Ali Arab
- Department of Pharmacology, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran,Corresponding author: Hossein-Ali Arab. Department of Pharmacology, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran. Tel: +98-21-61117086; Fax: +98-21-66933222;
| | - Hamid-Reza Kazerani
- Department of Physiology, Faculty of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad, Iran
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Allahyari S, Delazar A, Najafi M. Evaluation of general toxicity, anti-oxidant activity and effects of ficus carica leaves extract on ischemia/reperfusion injuries in isolated heart of rat. Adv Pharm Bull 2014; 4:577-82. [PMID: 25671192 DOI: 10.5681/apb.2014.085] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Revised: 11/08/2014] [Accepted: 11/11/2014] [Indexed: 01/26/2023] Open
Abstract
PURPOSE This study was aimed to evaluate general toxicity, anti-oxidant activity and effects of Ficus carica leaves extract on ischemia/reperfusion injuries. METHODS Antioxidant activity, total phenolic and flavonoid compounds of 70% methanolic extract of Ficus carica leaves were measured. The general toxicity test was carried out by brine shrimp lethality assay. Isolated hearts of male rats were mounted on a Langendorff apparatus and perfused with modified Krebs-Henseleit solution. In control group, the hearts were perfused with normal Krebs solution, however, treatment groups received enriched solution with the extract (0.04, 0.2 and 1 mg/ml) during stabilization and reperfusion (after 30 min global ischemia), respectively. Cardiac arrhythmias were analyzed and TTC method was used for infarct size determination. RESULTS The extract displayed antioxidant activity in the DPPH assay (RC50=0.06666 mg/ml). Total phenolic content was 12.29 mg GAE/100 g dry sample and the amount of flavonoids was calculated 40.729 mg/g. LD50 value by brine shrimp test was 0.158 mg/ml. The extract decreased number of VEBs, incidence and duration of Rev VF with clear reduction in infarct size and infarct volume (P<0.001). CONCLUSION Ficus carica decreased ischemia/reperfusion-induced injuries. These protections are probably due to antioxidant capacity and the existence of flavonoid and phenolic compounds in the extract.
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Affiliation(s)
- Saeideh Allahyari
- Student Research Committee, Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Abbas Delazar
- Department of Pharmacognosy, Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Moslem Najafi
- Department of Pharmacology, Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
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22
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Kralova E, Jankyova S, Mucaji P, Gresakova E, Stankovicova T. Pycnogenol® and its fractions influence the function of isolated heart in rats with experimental diabetes mellitus. Pathol Res Pract 2014; 211:156-61. [PMID: 25532475 DOI: 10.1016/j.prp.2014.11.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Revised: 11/03/2014] [Accepted: 11/17/2014] [Indexed: 10/24/2022]
Abstract
The aim of this study was to test the effect of Pycnogenol(®) (PYC) mixture and its three fractions (buthanolic, water, ethyl acetate) on heart function in rats with experimental diabetes mellitus (DM) and compare their effects to the diabetic group. Their antioxidant activity "in vitro" was also determined. DM rats (streptozotocin over 3 consecutive days at a dose of 25 mg/kg of body weight) had increased systolic blood pressure, thicker left ventriculi wall (LV) and weaker myocardial contraction, prolonged QT interval in comparison to controls rats. In comparison to the diabetic group, PYC (20 mg/kg b.w./day) suppressed the influence of DM on the LV, improved contraction, increased coronary flow and displayed negative effect on electrical activity of hearts. The most effective of PYC's fractions was the water fraction. It improved biometric parameters and hemodynamic function of the DM hearts, enhanced shortening the QT interval, reduced the amount of dysrhythmias of the DM hearts and had the strongest antioxidant activity. In conclusion, DM damaged isolated rat heart function. Only the water fraction improved the function of the diabetic heart. The different results of three fractions and PYC on myocardial function may be caused by a various lipo- and hydro-philic action of the PYC components.
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Affiliation(s)
- Eva Kralova
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Comenius University, Slovakia.
| | - Stanislava Jankyova
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Comenius University, Slovakia
| | - Pavel Mucaji
- Department of Pharmacognosy and Botany, Faculty of Pharmacy, Comenius University, Slovakia
| | - Eva Gresakova
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Comenius University, Slovakia
| | - Tatiana Stankovicova
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Comenius University, Slovakia
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23
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Lohezic M, Teh I, Bollensdorff C, Peyronnet R, Hales PW, Grau V, Kohl P, Schneider JE. Interrogation of living myocardium in multiple static deformation states with diffusion tensor and diffusion spectrum imaging. Prog Biophys Mol Biol 2014; 115:213-25. [PMID: 25117498 PMCID: PMC4210665 DOI: 10.1016/j.pbiomolbio.2014.08.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/22/2014] [Accepted: 08/02/2014] [Indexed: 11/27/2022]
Abstract
Diffusion tensor magnetic resonance imaging (MRI) reveals valuable insights into tissue histo-anatomy and microstructure, and has steadily gained traction in the cardiac community. Its wider use in small animal cardiac imaging in vivo has been constrained by its extreme sensitivity to motion, exaggerated by the high heart rates usually seen in rodents. Imaging of the isolated heart eliminates respiratory motion and, if conducted on arrested hearts, cardiac pulsation. This serves as an important intermediate step for basic and translational studies. However, investigating the micro-structural basis of cardiac deformation in the same heart requires observations in different deformation states. Here, we illustrate the imaging of isolated rat hearts in three mechanical states mimicking diastole (cardioplegic arrest), left-ventricular (LV) volume overload (cardioplegic arrest plus LV balloon inflation), and peak systole (lithium-induced contracture). An optimised MRI-compatible Langendorff perfusion setup with the radio-frequency (RF) coil integrated into the wet chamber was developed for use in a 9.4T horizontal bore scanner. Signal-to-noise ratio improved significantly, by 75% compared to a previous design with external RF coil, and stability tests showed no significant changes in mean T1, T2 or LV wall thickness over a 170 min period. In contracture, we observed a significant reduction in mean fractional anisotropy from 0.32 ± 0.02 to 0.28 ± 0.02, as well as a significant rightward shift in helix angles with a decrease in the proportion of left-handed fibres, as referring to the locally prevailing cell orientation in the heart, from 24.9% to 23.3%, and an increase in the proportion of right-handed fibres from 25.5% to 28.4%. LV overload, in contrast, gave rise to a decrease in the proportion of left-handed fibres from 24.9% to 21.4% and an increase in the proportion of right-handed fibres from 25.5% to 26.0%. The modified perfusion and coil setup offers better performance and control over cardiac contraction states. We subsequently performed high-resolution diffusion spectrum imaging (DSI) and 3D whole heart fibre tracking in fixed ex vivo rat hearts in slack state and contracture. As a model-free method, DSI augmented the measurements of water diffusion by also informing on multiple intra-voxel diffusion orientations and non-Gaussian diffusion. This enabled us to identify the transition from right- to left-handed fibres from the subendocardium to the subepicardium, as well as voxels in apical regions that were traversed by multiple fibres. We observed that both the mean generalised fractional anisotropy and mean kurtosis were lower in hearts in contracture compared to the slack state, by 23% and 9.3%, respectively. While its heavy acquisition burden currently limits the application of DSI in vivo, ongoing work in acceleration techniques may enable its use in live animals and patients. This would provide access to the as yet unexplored dimension of non-Gaussian diffusion that could serve as a highly sensitive marker of cardiac micro-structural integrity.
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Affiliation(s)
- Maelene Lohezic
- British Heart Foundation Experimental Magnetic Resonance Unit, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Irvin Teh
- British Heart Foundation Experimental Magnetic Resonance Unit, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Christian Bollensdorff
- National Heart and Lung Institute, Imperial College London, London, UK; Qatar Cardiovascular Research Center, Qatar Foundation, Doha, Qatar
| | - Rémi Peyronnet
- National Heart and Lung Institute, Imperial College London, London, UK
| | - Patrick W Hales
- Imaging and Biophysics Unit, Institute of Child Health, University College London, London, UK
| | - Vicente Grau
- Department of Engineering Science, University of Oxford, Oxford, UK
| | - Peter Kohl
- National Heart and Lung Institute, Imperial College London, London, UK; Department of Computer Science, University of Oxford, Oxford, UK
| | - Jürgen E Schneider
- British Heart Foundation Experimental Magnetic Resonance Unit, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK.
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Cinca J, Noriega FJ, Jorge E, Alvarez-Garcia J, Amoros G, Arzamendi D. ST-segment deviation behavior during acute myocardial ischemia in opposite ventricular regions: observations in the intact and perfused heart. Heart Rhythm 2014; 11:2084-91. [PMID: 25041965 DOI: 10.1016/j.hrthm.2014.07.019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Indexed: 11/19/2022]
Abstract
BACKGROUND Acute myocardial ischemia in opposite regions may attenuate ST-segment changes, but whether this effect is expressed differently in extracardiac compared to direct intramyocardial recordings is not well known. OBJECTIVE The purpose of this study was to characterize ST-segment changes induced by opposite ischemic regions in intact and isolated perfused pig hearts. METHODS Left anterior descending (LAD) and right coronary arteries (RCA) were occluded in 7 closed chest pigs and in 5 isolated pig hearts. ST-segment changes were analyzed in 12-lead ECG and in local extracellular electrograms. RESULTS Isolated LAD or RCA occlusion induced maximal ST-segment elevation in leads V4 (0.84 ± 0.30 mV, P = .003) and III (0.16 ± 0.11 mV, P = .04), respectively. RCA occlusion also induced reciprocal ST-segment depression maximal in lead V4 (-0.40 ± 0.16 mV, P = .005). Simultaneous LAD and RCA occlusion reduced ST-segment elevation by about 60% and blunted reciprocal ST-segment changes. Reperfusion of 1 of the 2 occluded arteries induced immediate regional reversion of ST-segment elevation with concurrent beat-to-beat re-elevation in the opposite ischemic region and reappearance of reciprocal ST-segment changes. In the isolated heart, single LAD or RCA ligature induced regional transmural ST-segment elevation that was maximal in endocardial electrograms with no appreciable reciprocal ST-segment depression. Simultaneous LAD and RCA ligature reduced ST-segment elevation by about 30% with no appreciable re-elevation after 1-vessel selective reperfusion. CONCLUSION Acute myocardial ischemia in opposite ventricular regions attenuated ST-segment elevation and blunted reciprocal depression in conventional ECG leads but not in direct local myocardial electrograms.
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Affiliation(s)
- Juan Cinca
- Department of Cardiology, Hospital de la Santa Creu i Sant Pau, Institute of Biomedical Research IIB Sant Pau, Universitat Autònoma de Barcelona, Barcelona, Spain.
| | - Francisco Javier Noriega
- Department of Cardiology, Hospital de la Santa Creu i Sant Pau, Institute of Biomedical Research IIB Sant Pau, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Esther Jorge
- Department of Cardiology, Hospital de la Santa Creu i Sant Pau, Institute of Biomedical Research IIB Sant Pau, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Jesús Alvarez-Garcia
- Department of Cardiology, Hospital de la Santa Creu i Sant Pau, Institute of Biomedical Research IIB Sant Pau, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Gerard Amoros
- Department of Cardiology, Hospital de la Santa Creu i Sant Pau, Institute of Biomedical Research IIB Sant Pau, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Dabit Arzamendi
- Department of Cardiology, Hospital de la Santa Creu i Sant Pau, Institute of Biomedical Research IIB Sant Pau, Universitat Autònoma de Barcelona, Barcelona, Spain
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Eggen MD, Bonner MD, Williams ER, Iaizzo PA. Multimodal imaging of a transcatheter pacemaker implantation within a reanimated human heart. Heart Rhythm 2014; 11:2331-2. [PMID: 24732365 DOI: 10.1016/j.hrthm.2014.03.052] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Indexed: 10/25/2022]
Affiliation(s)
| | | | | | - Paul A Iaizzo
- Department of Surgery, University of Minnesota, Minneapolis, Minnesota.
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Aune SE, Herr DJ, Mani SK, Menick DR. Selective inhibition of class I but not class IIb histone deacetylases exerts cardiac protection from ischemia reperfusion. J Mol Cell Cardiol 2014; 72:138-45. [PMID: 24632412 DOI: 10.1016/j.yjmcc.2014.03.005] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2013] [Revised: 02/18/2014] [Accepted: 03/05/2014] [Indexed: 12/20/2022]
Abstract
While inhibition of class I/IIb histone deacetylases (HDACs) protects the mammalian heart from ischemia reperfusion (IR) injury, class selective effects remain unexamined. We hypothesized that selective inhibition of class I HDACs would preserve left ventricular contractile function following IR in isolated hearts. Male Sprague Dawley rats (n=6 per group) were injected with vehicle (dimethylsulfoxide, 0.63mg/kg), the class I/IIb HDAC inhibitor trichostatin A (1mg/kg), the class I HDAC inhibitor entinostat (MS-275, 10mg/kg), or the HDAC6 (class IIb) inhibitor tubastatin A (10mg/kg). After 24h, hearts were isolated and perfused in Langendorff mode for 30min (Sham) or subjected to 30min global ischemia and 120min global reperfusion (IR). A saline filled balloon attached to a pressure transducer was placed in the LV to monitor contractile function. After perfusion, LV tissue was collected for measurements of antioxidant protein levels and infarct area. At the conclusion of IR, MS-275 pretreatment was associated with significant preservation of developed pressure, rate of pressure generation, rate of pressure relaxation and rate pressure product, as compared to vehicle treated hearts. There was significant reduction of infarct area with MS-275 pretreatment. Contractile function was not significantly restored in hearts treated with trichostatin A or tubastatin A. Mitochondrial superoxide dismutase (SOD2) and catalase protein and mRNA in hearts from animals pretreated with MS-275 were increased following IR, as compared to Sham. This was associated with a dramatic enrichment of nuclear FOXO3a transcription factor, which mediates the expression of SOD2 and catalase. Tubastatin A treatment was associated with significantly decreased catalase levels after IR. Class I HDAC inhibition elicits protection of contractile function following IR, which is associated with increased expression of endogenous antioxidant enzymes. Class I/IIb HDAC inhibition with trichostatin A or selective inhibition of HDAC6 with tubastatin A was not protective. This study highlights the need for the development of new strategies that target specific HDAC isoforms in cardiac ischemia reperfusion.
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Affiliation(s)
- Sverre E Aune
- Gazes Cardiac Research Institute, Medical University of South Carolina, 114 Doughty St., Charleston, SC 29425, USA
| | - Daniel J Herr
- Gazes Cardiac Research Institute, Medical University of South Carolina, 114 Doughty St., Charleston, SC 29425, USA
| | - Santhosh K Mani
- Gazes Cardiac Research Institute, Medical University of South Carolina, 114 Doughty St., Charleston, SC 29425, USA
| | - Donald R Menick
- Gazes Cardiac Research Institute, Medical University of South Carolina, 114 Doughty St., Charleston, SC 29425, USA.
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Abstract
BACKGROUND Myocardial reperfusion therapy remains the most effective strategy to limit infarct size and improve clinical outcome. However, reperfusion injury is still inevitable, and a number of strategies have been developed to ameliorate its lethal outcome. The beneficial roles of ischemic postconditioning (Ipost) have regained more interest in targeting myocardial reperfusion phase to improve cardioprotection. AIMS This study was to determine whether acute or chronic treatment with atorvastatin affects cardioprotection when it was combined with Ipost. RESULTS Acute or chronic atorvastatin treatment significantly reduced infarct size and recovered contractile dysfunction during reperfusion. When Ipost was combined with atorvastatin treatment, chronic, but not acute, atorvastatin therapy attenuated the cardioprotective effects of Ipost. Chronic, but not acute, atorvastatin treatment also abolished Ipost-induced phosphorylation level of Akt and endothelial nitric oxide synthase (eNOS). CONCLUSIONS Chronic atorvastatin treatment could interfere with cardioprotective effects of Ipost on limiting infarct size and contractile dysfunction, possibly via inhibition of Akt and eNOS activity. This study suggests that Ipost should be used carefully when atorvastatin is taken by patients with AMI.
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Affiliation(s)
- Ying Fan
- Department of Cardiology, The First Affiliated Hospital of Harbin Medical University, Heilongjiang, China
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Onitsuka K, Ide T, Arai S, Hata Y, Murayama Y, Hosokawa K, Sakamoto T, Tobushi T, Sakamoto K, Fujino T, Sunagawa K. Cardiac phase-targeted dynamic load on left ventricle differentially regulates phase-sensitive gene expressions and pathway activation. J Mol Cell Cardiol 2013; 64:30-8. [PMID: 24004468 DOI: 10.1016/j.yjmcc.2013.08.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Revised: 08/07/2013] [Accepted: 08/26/2013] [Indexed: 12/15/2022]
Abstract
The heart has remarkable capacity to adapt to mechanical load and to dramatically change its phenotype. The mechanism underlying such diverse phenotypic adaptations remains unknown. Since systolic overload induces wall thickening, while diastolic overload induces chamber enlargement, we hypothesized that cardiac phase-sensitive mechanisms govern the adaptation. We inserted a balloon into the left ventricle (LV) of a Langendorff perfused rat heart, and controlled LV volume (LVV) using a high performance servo-pump. We created isolated phasic systolic overload (SO) by isovolumic contraction (peak LV pressure >170mmHg) at unstressed diastolic LVV [end-diastolic pressure (EDP)=0mmHg]. We also created pure phasic diastolic overload (DO) by increasing diastolic LVV until EDP >40mmHg and unloading completely in systole. After 3hours under each condition, the myocardium was analyzed using DNA microarray. Gene expressions under SO and DO conditions were compared against unloaded control condition using gene ontology and pathway analysis (n=4 each). SO upregulated proliferation-related genes, whereas DO upregulated fibrosis-related genes (P<10(-5)). Both SO and DO upregulated genes related functionally to cardiac hypertrophy, although the gene profiles were totally different. Upstream regulators confirmed by Western blot indicated that SO activated extracellular signal-regulated kinase 1/2, c-Jun NH2-terminal kinase, and Ca(2+)/calmodulin-dependent protein kinase II (3.2-, 2.0-, and 4.7-fold versus control, P<0.05, n=5), whereas DO activated p38 (2.9-fold, P<0.01), which was consistent with the downstream gene expressions. In conclusion, pure isolated systolic and diastolic overload permits elucidation of cardiac phase-sensitive gene regulation. The genomic responses indicate that mechanisms governing the cardiac phase-sensitive adaptations are different.
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Affiliation(s)
- Ken Onitsuka
- Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kyushu University, 3-1-1, Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
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Henderson KA, Borders RB, Ross JB, Huwar TB, Travis CO, Wood BJ, Ma ZJ, Hong SP, Vinci TM, Roche BM. Effects of tyrosine kinase inhibitors on rat isolated heart function and protein biomarkers indicative of toxicity. J Pharmacol Toxicol Methods 2013; 68:150-9. [PMID: 23660125 DOI: 10.1016/j.vascn.2013.04.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2013] [Revised: 04/17/2013] [Accepted: 04/25/2013] [Indexed: 11/18/2022]
Abstract
INTRODUCTION Cardiac toxicity, manifested as diminished contractility, ischemic heart disease, and heart failure is a major issue in drug safety. Concerns revolve around targeted drugs (TKIs) where contractility effects were not anticipated. The ability to predict cardiac toxicity early would help to de-risk drugs in development and prepare physicians to manage risk in the clinic. Issues with current preclinical studies include insufficient testing with informative, translatable models, and predictive biomarkers. The isolated heart model is amenable to multiple assessments which can be combined with current technologies to assess toxicity on a multi-scale level. METHODS Rat isolated heart model was used to assess changes in left ventricular (LV) contractility and protein biomarkers BNP, IL6, TNFα, and cardiac troponins T (TnT) and I (TnI). Responses were assessed during perfusion with modified Henseleit Krebs (MHK), and 20 min concentration escalations of verapamil, carbonyl cyanide 4-(trifluoromethoxy)phenylhydrazone (FCCP), isoproterenol, or 20 min escalations bracketing clinical blood concentrations of sunitinib, sorafenib, and erlotinib. LV parameters and effluent for biomarkers were collected before and during escalating drug concentrations. RESULTS Verapamil reduced inotropy with no change in biomarkers, FCCP and isoproterenol reduced and increased heart function respectively and increased TnT and TNFα. Erlotinib had no significant effects on function or biomarkers. Sunitinib diminished function, increased TNFα at 0.1 μM, and increased TnT at higher concentrations. Sorafenib dose dependently increased TNFα beginning at 0.1 μM, reducing contractility and flow rate at 0.6 μM. DISCUSSION The ex-vivo assay is a sensitive and predictive model for assessing changes in heart function and biomarkers of toxicity and injury. This assay demonstrates the potential for sunitinib and sorafenib to cause cardiac toxicity in humans. Also, TNFα appears to be a biomarker in the heart prior to injury. Due to its versatility, the isolated heart assay has potential to fill gaps in cardiac safety testing early in drug development.
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Soliman M. Inhibition of Na(+)-H(+) exchange before resuscitation following hemorrhagic shock is cardioprotective in rats. J Saudi Heart Assoc 2009; 21:159-63. [PMID: 23960566 DOI: 10.1016/j.jsha.2009.06.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2009] [Accepted: 06/01/2009] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Stimulation of the Na(+)-H(+) exchanger during resuscitation following hemorrhagic shock results in myocardial injury and dysfunction. Inhibition of the Na(+)-H(+) exchanger appears to be a new pharmacological tool for myocardial protection following ischemia-reperfusion. Our lab showed that inhibition of the Na(+)-H(+) exchanger, using amiloride and dimethyl amiloride, before ex vivo resuscitation of isolated perfused hearts protected the myocardium and improved the post-resuscitation myocardial function. The purpose of the present study was to examine the myocardial protective effects of treating the hemorrhagic shocked rats by intra-arterial injection of 20 μM dimethyl amiloride (DMA), a specific Na(+)-H(+) exchanger blocker, before in vivo resuscitation. METHODS Sprague-Dawley rats were assigned to hemorrhagic treated or untreated groups (n = 4 per group). After 60 min of hemorrhagic shock, rats were treated or not by injection of 20 μM 5-(N,N-dimethyl)-amiloride (DMA) intra-arterially. Rats were then resuscitated in vivo and monitored for 30 min. Then hearts were harvested and perfused in the Langendorff system for 60 min for measurements of hemodynamic function. RESULTS Administration of DMA before in vivo resuscitation following 60 min of hemorrhagic shock and 30 min of in vivo resuscitation, 20 μM DMA intra-arterially significantly improved post-resuscitation myocardial function. CONCLUSION Our results suggest that DMA protects the heart against post-resuscitation myocardial injury.
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Affiliation(s)
- Mona Soliman
- Department of Physiology, College of Medicine, King Khalid University Hospital, P.O. Box 2925 (29), Riyadh 11461, Saudi Arabia
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Portnychenko AG, Harmatina OY, Kotsuruba AV, Moybenko OO. The role of nitric oxide in endotoxin-induced cardiodepression. Exp Clin Cardiol 2005; 10:223-228. [PMID: 19641673 PMCID: PMC2716236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
OBJECTIVE To determine the participation of inducible nitric oxide synthase (iNOS) in cardiodepressive phenomena during late preconditioning caused by subtoxic doses of lipopolysaccharide (LPS). METHODS Spontaneously beating hearts isolated from male Wistar rats (350 g to 400 g), intact or preconditioned with LPS (0.25 mg/kg given intraperitoneally 18 h before heart excision), were used to measure contractile performance during 30 min of ischemia and 40 min of reperfusion in the Langendorff mode. For selective iNOS blockade, hearts were perfused with phenylene-1,3-bis(ethane-2-isothiourea) (50 nmol/L). Expression of iNOS (determined using Western blotting) and NOS activities were determined in frozen myocardial tissues. RESULTS Subtoxic doses of LPS caused iNOS induction in the heart and depression of contractile function, but improved heart postischemic recovery. In all groups of animals, expression of iNOS was higher in the right than left ventricles. Ischemia and postischemic reperfusion of intact heart intensified production of nitric oxide (NO), predominantly by iNOS. The preconditioning led to iNOS activation during ischemia in the left ventricle and iNOS depression in the right ventricle, owing to feedback caused by the initially higher iNOS expression and activity in the right ventricle. Postischemic reperfusion diminished NOS activities in preconditioned myocardial tissues. Blockade of iNOS significantly slowed preconditioned heart recovery and partially restored left ventricular developed pressure, but only after 20 min of reperfusion. CONCLUSIONS iNOS-produced NO plays a role in the development of delayed cardioprotection and cardiodepressive effects (in part) after extravasal administration of a minimal dose of endotoxin.
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Affiliation(s)
| | - Olga Yu Harmatina
- Bogomoletz Institute of Physiology, National Academy of Sciences of Ukraine
| | - Anatolij V Kotsuruba
- Bogomoletz Institute of Physiology, National Academy of Sciences of Ukraine
- Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv, Ukraine
| | - Oleksij O Moybenko
- Bogomoletz Institute of Physiology, National Academy of Sciences of Ukraine
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Müller-Strahl G, Hemker J, Zimmer HG. Comparison between left and right heart function in the isolated biventricular working rat heart. Exp Clin Cardiol 2002; 7:7-19. [PMID: 19644573 PMCID: PMC2716184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
OBJECTIVE To provide a basic characterization of the crystalline perfused isolated rat heart preparation in its biventricular working mode. ANIMALS AND METHODS In 110 isolated biventricular heart preparations, flows and intraventricular pressures were examined by applying 24 and 28 different loading conditions to the left (LV) and right ventricle (RV), respectively. RESULTS LV and RV flows responded analogously to changes in loading conditions and were in accordance with the Frank-Starling principle. Linearization of parameters derived from the LV and RV function curves showed that the operation of both ventricles was quantitatively similar when unloaded and increasingly dissimilar when loaded. With increasing RV preload, the characteristics of the RV pump function curves changed; however, those of the LV hardly changed. Power, contractility and relaxation data of the ventricles were compared by applying the concept of corresponding afterloads, which showed that these parameters, except for power, had an inconsistent preload and afterload dependence in the LV and RV. Even though LV and RV performances displayed coexisting analogies, quantitative similarities and qualitative dissimilarities, in the case of relaxation, a concept unifying the heterogeneous data set for both ventricles has been developed. The hypothesis may be put forward that the macroscopic relaxation process of the heart muscle runs in parallel with cellular calcium handling. CONCLUSIONS At the level of the isolated denervated rat heart model, the common LV and RV functional parameters were only partially similar between the ventricles. However, a particular functional interdependence of relaxation data has been proposed to provide a unifying description of both LV and RV function.
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Affiliation(s)
| | - Jan Hemker
- Carl-Ludwig-Institut für Physiologie, Universität Leipzig, Leipzig, Germany
| | - Heinz-Gerd Zimmer
- Carl-Ludwig-Institut für Physiologie, Universität Leipzig, Leipzig, Germany
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