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Bigelman E, Cohen L, Aharon-Hananel G, Levy R, Rozenbaum Z, Saada A, Keren G, Entin-Meer M. Pathological presentation of cardiac mitochondria in a rat model for chronic kidney disease. PLoS One 2018; 13:e0198196. [PMID: 29889834 PMCID: PMC5995391 DOI: 10.1371/journal.pone.0198196] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Accepted: 05/15/2018] [Indexed: 01/27/2023] Open
Abstract
BACKGROUND Mitochondria hold crucial importance in organs with high energy demand especially the heart. We investigated whether chronic kidney disease (CKD), which eventually culminates in cardiorenal syndrome, could affect cardiac mitochondria and assessed the potential involvement of angiotensin II (AngII) in the process. METHODS Male Lewis rats underwent 5/6 nephrectomy allowing CKD development for eight months or for eleven weeks. Short-term CKD rats were administered with AngII receptor blocker (ARB). Cardiac function was assessed by echocardiography and cardiac sections were evaluated for interstitial fibrosis and cardiomyocytes' hypertrophy. Electron microscopy was used to explore the spatial organization of the cardiomyocytes. Expression levels of mitochondrial content and activity markers were tested in order to delineate the underlying mechanisms for mitochondrial pathology in the CKD setting with or without ARB administration. RESULTS CKD per-se resulted in induced cardiac interstitial fibrosis and cardiomyocytes' hypertrophy combined with a marked disruption of the mitochondrial structure. Moreover, CKD led to enhanced cytochrome C leakage to the cytosol and to enhanced PARP-1 cleavage which are associated with cellular apoptosis. ARB treatment did not improve kidney function but markedly reduced left ventricular mass, cardiomyocytes' hypertrophy and interstitial fibrosis. Interestingly, ARB administration improved the spatial organization of cardiac mitochondria and reduced their increased volume compared to untreated CKD animals. Nevertheless, ARB did not improve mitochondrial content, mitochondrial biogenesis or the respiratory enzyme activity. ARB mildly upregulated protein levels of mitochondrial fusion-related proteins. CONCLUSIONS CKD results in cardiac pathological changes combined with mitochondrial damage and elevated apoptotic markers. We anticipate that the increased mitochondrial volume mainly represents mitochondrial swelling that occurs during the pathological process of cardiac hypertrophy. Chronic administration of ARB may improve the pathological appearance of the heart. Further recognition of the molecular pathways leading to mitochondrial insult and appropriate intervention is of crucial importance.
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Affiliation(s)
- Einat Bigelman
- Sackler School of Medicine, Tel-Aviv University, Tel-Aviv, Israel
- The Laboratory of Cardiovascular Research, Department of Cardiology, Tel-Aviv Sourasky Medical Center, Tel-Aviv, Israel
| | - Lena Cohen
- Sackler School of Medicine, Tel-Aviv University, Tel-Aviv, Israel
- The Laboratory of Cardiovascular Research, Department of Cardiology, Tel-Aviv Sourasky Medical Center, Tel-Aviv, Israel
| | | | - Ran Levy
- The Laboratory of Cardiovascular Research, Department of Cardiology, Tel-Aviv Sourasky Medical Center, Tel-Aviv, Israel
| | - Zach Rozenbaum
- Sackler School of Medicine, Tel-Aviv University, Tel-Aviv, Israel
- The Laboratory of Cardiovascular Research, Department of Cardiology, Tel-Aviv Sourasky Medical Center, Tel-Aviv, Israel
| | - Ann Saada
- Department of Genetic and Metabolic Diseases, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Gad Keren
- Sackler School of Medicine, Tel-Aviv University, Tel-Aviv, Israel
- The Laboratory of Cardiovascular Research, Department of Cardiology, Tel-Aviv Sourasky Medical Center, Tel-Aviv, Israel
| | - Michal Entin-Meer
- Sackler School of Medicine, Tel-Aviv University, Tel-Aviv, Israel
- The Laboratory of Cardiovascular Research, Department of Cardiology, Tel-Aviv Sourasky Medical Center, Tel-Aviv, Israel
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Bhatnagar A, Unal H, Jagannathan R, Kaveti S, Duan ZH, Yong S, Vasanji A, Kinter M, Desnoyer R, Karnik SS. Interaction of G-protein βγ complex with chromatin modulates GPCR-dependent gene regulation. PLoS One 2013; 8:e52689. [PMID: 23326349 PMCID: PMC3541368 DOI: 10.1371/journal.pone.0052689] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2012] [Accepted: 11/19/2012] [Indexed: 11/21/2022] Open
Abstract
Heterotrimeric G-protein signal transduction initiated by G-protein-coupled receptors (GPCRs) in the plasma membrane is thought to propagate through protein-protein interactions of subunits, Gα and Gβγ in the cytosol. In this study, we show novel nuclear functions of Gβγ through demonstrating interaction of Gβ2 with integral components of chromatin and effects of Gβ2 depletion on global gene expression. Agonist activation of several GPCRs including the angiotensin II type 1 receptor specifically augmented Gβ2 levels in the nucleus and Gβ2 interacted with specific nucleosome core histones and transcriptional modulators. Depletion of Gβ2 repressed the basal and angiotensin II-dependent transcriptional activities of myocyte enhancer factor 2. Gβ2 interacted with a sequence motif that was present in several transcription factors, whose genome-wide binding accounted for the Gβ2-dependent regulation of approximately 2% genes. These findings suggest a wide-ranging mechanism by which direct interaction of Gβγ with specific chromatin bound transcription factors regulates functional gene networks in response to GPCR activation in cells.
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Affiliation(s)
- Anushree Bhatnagar
- Department of Molecular Cardiology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
| | - Hamiyet Unal
- Department of Molecular Cardiology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
| | - Rajaganapathi Jagannathan
- Department of Molecular Cardiology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
| | - Suma Kaveti
- Department of Cell Biology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
| | - Zhong-Hui Duan
- Department of Molecular Cardiology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
- Department of Computer Science, University of Akron, Akron, Ohio, United States of America
| | - Sandro Yong
- Department of Molecular Cardiology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
| | - Amit Vasanji
- Biomedical Imaging and Analysis Core, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
| | - Michael Kinter
- Department of Cell Biology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
| | - Russell Desnoyer
- Department of Molecular Cardiology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
| | - Sadashiva S. Karnik
- Department of Molecular Cardiology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
- * E-mail:
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Oliveira LPJ, Lawless CE. Hypertension update and cardiovascular risk reduction in physically active individuals and athletes. PHYSICIAN SPORTSMED 2010; 38:11-20. [PMID: 20424397 DOI: 10.3810/psm.2010.04.1757] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Hypertension is a prevalent disease worldwide. Its inadequate treatment leads to major cardiovascular complications, such as myocardial infarction, stroke, and heart failure. These conditions decrease life expectancy and are a substantial cost burden to health care systems. Physically active individuals and professional athletes are not risk free for developing this condition. Although the percentage of persons affected is substantially lower than the general population, these individuals still need to be thoroughly evaluated and blood pressure targets monitored to allow safe competitive sports participation. Regarding treatment, lifestyle modification measures should be routinely emphasized to athletes and active individuals with the same importance as for the general population. Medication treatment can be complicated because of restrictions by athletic organizations and possible limitations on maximal exercise performance. In addition, the choice of an antihypertensive drug should be made with consideration for salt and water losses that routinely occur in athletes, as well as preservation of exercise performance and endothelial function. First-line therapies for athletes and physically active individuals may be different from the general population. Some authorities believe that blocking the renin-angiotensin system with angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs) is more beneficial compared with diuretics because of ACE inhibitors and ARBs being able to avoid salt and water losses. Dihydropyridine calcium channel blockers (CCBs) are another reasonable choice. Despite effects on heart rate, nondihydropyridine CCBs do not appear to impair exercise performance. beta-Blockers are not used as a first-line therapy in athletes because of effects on exercise and prohibition by the National Collegiate Athletic Association and World Anti-Doping Agency in certain sports. In this article, we address the evidence on hypertension and its related treatments in active individuals to provide recommendations that allow the best competitive sports results and reduce cardiovascular risk.
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Abstract
Antiarrhythmic drug therapy, broadly defined, is the mainstay of treatment and prevention of ventricular tachycardia (VT)/ventricular fibrillation (VF), which can lead to sudden death. This article evaluates the evidence for and appropriate use of class I antiarrhythmic drugs, class III antiarrhythmic drugs, beta-blockers, nondihydropyridine calcium-channel blockers, statins, angiotensin enzyme inhibitors, angiotensin receptor blockers, aldosterone blockers, and digoxin for antiarrhythmic benefits in patients who have a propensity for VT/VF and therefore are at risk of sudden death.
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