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Ventricular assist device-promoted recovery and technical aspects of explant. JTCVS Tech 2021; 7:182-188. [PMID: 34318239 PMCID: PMC8311694 DOI: 10.1016/j.xjtc.2021.02.023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2021] [Accepted: 02/11/2021] [Indexed: 01/09/2023] Open
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2
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Abstract
Heart failure is a widespread condition in the United States that is predicted to significantly increase in prevalence in the next decade. Many heart failure patients are given a left ventricular assist device (LVAD) while they wait for a heart transplant, while those that are not able to undergo a heart transplant may be given an LVAD permanently. However, past studies have observed a small subset of heart failure patients that recovered cardiac function of their native heart after being placed on an LVAD. As a result, some patients have been able to have their LVAD explanted and no longer needed a heart transplant. In this review, we analyzed the data of 15 studies that observed recovery of cardiac function in LVAD patients in order to investigate the effects that duration of LVAD support has on patient outcomes. From our review, we identified that there may be negative consequences of prolonged duration of mechanical support such as myocardial atrophy and abnormal calcium cycling as well as circumstances that may allow for a longer duration of LVAD support such as in patients using a continuous-flow LVAD, non-ischemic cardiomyopathy patients, and the specific pharmacological therapy.
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Affiliation(s)
- Binh N Pham
- University of Miami, Miller School of Medicine, Miami, FL, USA
| | - Sandra V Chaparro
- University of Miami, Miller School of Medicine, Miami, FL, USA.
- Department of Medicine, Cardiovascular Division, University of Miami Miller School of Medicine, Clinical Research Building, 1120 NW 14th Street, Room 1110, Miami, FL, 33136, USA.
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3
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Left Ventricular Assist Device Decommissioning Compared with Explantation for Ventricular Recovery: A Systematic Review. ASAIO J 2020; 66:17-22. [DOI: 10.1097/mat.0000000000000926] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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4
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Dokuchaev A, Khamzin S, Solovyova O. In-silico study of age-related ionic remodeling in human ventricular cardiomyocytes. BIO WEB OF CONFERENCES 2020. [DOI: 10.1051/bioconf/20202201024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Ageing is one of the dominant risk factors for cardiovascular diseases. A large number of experimental data is collected on the cellular remodeling in the ageing myocardium from mammals, but very little is known about the human cardiomyocytes. We used a combined electro-mechanical model of human ventricular cardiomyocytes and a population of models approach to investigate the variability in the response of cardiomyocytes to age-related changes in model parameters of the ionic currents.
To generate a control model population, we varied 9 ionic parameters and excluded model samples with biomarkers of cellular action potential (AP) and Ca2+ transient (CT) falling outside the physiological ranges. Using the control population of models, we evaluated the response to age-related reduction in the K+ transient outward current, SERCA pump, and an increase in the Na+Ca2+ exchange current and L-type Ca2+ current. Then, we randomly generated 60 age-related sets of the 4 parameters and applied each set to every model in the control population. We showed an increase in the frequency of repolarization anomalies (RA) and critical AP prolongation in the ageing model populations suggesting arrhythmogenic effects of the ionic remodeling. The population based approach allowed us to assess the pro-arrhythmic contribution of the ionic parameters in ageing cardiomyocytes.
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Pokorný M, Mrázová I, Malý J, Pirk J, Netuka I, Vaňourková Z, Doleželová Š, Červenková L, Maxová H, Melenovský V, Šochman J, Sadowski J, Červenka L. Effects of increased myocardial tissue concentration of myristic, palmitic and palmitoleic acids on the course of cardiac atrophy of the failing heart unloaded by heterotopic transplantation. Physiol Res 2018; 67:13-30. [PMID: 29137478 DOI: 10.33549/physiolres.933637] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The present experiments were performed to evaluate if increased heart tissue concentration of fatty acids, specifically myristic, palmitic and palmitoleic acids that are believed to promote physiological heart growth, can attenuate the progression of unloading-induced cardiac atrophy in rats with healthy and failing hearts. Heterotopic abdominal heart transplantation (HT(x)) was used as a model for heart unloading. Cardiac atrophy was assessed from the ratio of the native- to-transplanted heart weight (HW). The degree of cardiac atrophy after HT(x) was determined on days 7, 14, 21 and 28 after HT(x) in recipients of either healthy or failing hearts. HT(x) of healthy hearts resulted in 23+/-3, 46+/-3, 48+/-4 and 46+/-4 % HW loss at the four time-points. HT(x) of the failing heart resulted in even greater HW losses, of 46+/-4, 58+/-3, 66+/-2 and 68+/-4 %, respectively (P<0.05). Activation of "fetal gene cardiac program" (e.g. beta myosin heavy chain gene expression) and "genes reflecting cardiac remodeling" (e.g. atrial natriuretic peptide gene expression) after HT(x) was greater in failing than in healthy hearts (P<0.05 each time). Exposure to isocaloric high sugar diet caused significant increases in fatty acid concentrations in healthy and in failing hearts. However, these increases were not associated with any change in the course of cardiac atrophy, similarly in healthy and post-HT(x) failing hearts. We conclude that increasing heart tissue concentrations of the fatty acids allegedly involved in heart growth does not attenuate the unloading-induced cardiac atrophy.
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Affiliation(s)
- M Pokorný
- Institute for Clinical and Experimental Medicine, Prague, Czech Republic.
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6
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Chen M, Liu C, Wang M, Wang H, Zhang K, Zheng Y, Yu Z, Li X, Guo W, Li N, Meng Q. Clenbuterol Induces Cell Cycle Arrest in C2C12 Myoblasts by Delaying p27 Degradation through β-arrestin 2 Signaling. Int J Biol Sci 2017; 13:1341-1350. [PMID: 29104500 PMCID: PMC5666532 DOI: 10.7150/ijbs.17948] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Accepted: 06/16/2017] [Indexed: 02/04/2023] Open
Abstract
β2-Adrenoceptor (β2-AR) agonists promote muscle growth. The aim of this study was to elucidate some effects of the selective β2-adrenoceptor agonist clenbuterol (CLB) on myoblast proliferation. We found that CLB induces cell cycle arrest in C2C12 myoblasts. This effect is partly due to the enhanced stability of p27, rather than the increased gene transcription via cAMP response element-binding protein (CREB). Specifically, CLB treatment enhanced the accumulation of p27 in the nucleus while depleting it from the cytosol via a mechanism that requires β2-AR. Surprisingly, p27 accumulation was not reversed by the protein kinase A (PKA) inhibitor H-89, but interestingly, was alleviated by the knockdown of β-arrestin 2. Thus, our work provides a basis for β2-AR agonists inhibit myoblasts proliferation through signaling via β2-AR, β-arrestin 2, and p27.
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Affiliation(s)
- Min Chen
- State Key Laboratory for Agrobiotechnology, China Agricultural University, Beijing 100193, China.,Guangxi Province Center for Disease Control and Prevention, Nanning 530028, China
| | - Chuncheng Liu
- State Key Laboratory for Agrobiotechnology, China Agricultural University, Beijing 100193, China
| | - Meng Wang
- State Key Laboratory for Agrobiotechnology, China Agricultural University, Beijing 100193, China
| | - Hong Wang
- State Key Laboratory for Agrobiotechnology, China Agricultural University, Beijing 100193, China
| | - Kuo Zhang
- State Key Laboratory for Agrobiotechnology, China Agricultural University, Beijing 100193, China
| | - Yu Zheng
- State Key Laboratory for Agrobiotechnology, China Agricultural University, Beijing 100193, China
| | - Zhengquan Yu
- State Key Laboratory for Agrobiotechnology, China Agricultural University, Beijing 100193, China
| | - Xiangdong Li
- State Key Laboratory for Agrobiotechnology, China Agricultural University, Beijing 100193, China
| | - Wei Guo
- Animal Science/Molecular Biology Bldg, University of Wyoming, Laramie WY82071, USA
| | - Ning Li
- State Key Laboratory for Agrobiotechnology, China Agricultural University, Beijing 100193, China
| | - Qingyong Meng
- State Key Laboratory for Agrobiotechnology, China Agricultural University, Beijing 100193, China.,Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Biological Science, China Agricultural University
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7
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Heterotopic Abdominal Rat Heart Transplantation as a Model to Investigate Volume Dependency of Myocardial Remodeling. Transplantation 2017; 101:498-505. [PMID: 27906830 DOI: 10.1097/tp.0000000000001585] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Heterotopic abdominal rat heart transplantation has been extensively used to investigate ischemic-reperfusion injury, immunological consequences during heart transplantations and also to study remodeling of the myocardium due to volume unloading. We provide a unique review on the latter and present a summary of the experimental studies on rat heart transplantation to illustrate changes that occur to the myocardium due to volume unloading. We divided the literature based on whether normal or failing rat heart models were used. This analysis may provide a basis to understand the physiological effects of mechanical circulatory support therapy.
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Ohnuki Y, Umeki D, Mototani Y, Shiozawa K, Nariyama M, Ito A, Kawamura N, Yagisawa Y, Jin H, Cai W, Suita K, Saeki Y, Fujita T, Ishikawa Y, Okumura S. Role of phosphodiesterase 4 expression in the Epac1 signaling-dependent skeletal muscle hypertrophic action of clenbuterol. Physiol Rep 2016; 4:4/10/e12791. [PMID: 27207782 PMCID: PMC4886163 DOI: 10.14814/phy2.12791] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2015] [Accepted: 04/08/2016] [Indexed: 02/04/2023] Open
Abstract
Clenbuterol (CB), a selective β2-adrenergic receptor (AR) agonist, induces muscle hypertrophy and counteracts muscle atrophy. However, it is paradoxically less effective in slow-twitch muscle than in fast-twitch muscle, though slow-twitch muscle has a greater density of β-AR We recently demonstrated that Epac1 (exchange protein activated by cyclic AMP [cAMP]1) plays a pivotal role in β2-AR-mediated masseter muscle hypertrophy through activation of the Akt and calmodulin kinase II (CaMKII)/histone deacetylase 4 (HDAC4) signaling pathways. Here, we investigated the role of Epac1 in the differential hypertrophic effect of CB using tibialis anterior muscle (TA; typical fast-twitch muscle) and soleus muscle (SOL; typical slow-twitch muscle) of wild-type (WT) and Epac1-null mice (Epac1KO). The TA mass to tibial length (TL) ratio was similar in WT and Epac1KO at baseline and was significantly increased after CB infusion in WT, but not in Epac1KO The SOL mass to TL ratio was also similar in WT and Epac1KO at baseline, but CB-induced hypertrophy was suppressed in both mice. In order to understand the mechanism involved, we measured the protein expression levels of β-AR signaling-related molecules, and found that phosphodiesterase 4 (PDE4) expression was 12-fold greater in SOL than in TA These results are consistent with the idea that increased PDE4-mediated cAMP hydrolysis occurs in SOL compared to TA, resulting in a reduced cAMP concentration that is insufficient to activate Epac1 and its downstream Akt and CaMKII/HDAC4 hypertrophic signaling pathways in SOL of WT This scenario can account for the differential effects of CB on fast- and slow-twitch muscles.
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Affiliation(s)
- Yoshiki Ohnuki
- Department of Physiology, Tsurumi University School of Dental Medicine, Yokohama, Japan
| | - Daisuke Umeki
- Department of Physiology, Tsurumi University School of Dental Medicine, Yokohama, Japan Department of Orthodontics, Tsurumi University School of Dental Medicine, Yokohama, Japan
| | - Yasumasa Mototani
- Department of Physiology, Tsurumi University School of Dental Medicine, Yokohama, Japan
| | - Kouichi Shiozawa
- Department of Physiology, Tsurumi University School of Dental Medicine, Yokohama, Japan
| | - Megumi Nariyama
- Department of Physiology, Tsurumi University School of Dental Medicine, Yokohama, Japan Department of Pediatric Dentistry, Tsurumi University School of Dental Medicine, Yokohama, Japan
| | - Aiko Ito
- Department of Physiology, Tsurumi University School of Dental Medicine, Yokohama, Japan Department of Orthodontics, Tsurumi University School of Dental Medicine, Yokohama, Japan
| | - Naoya Kawamura
- Department of Physiology, Tsurumi University School of Dental Medicine, Yokohama, Japan Department of Periodontology, Tsurumi University School of Dental Medicine, Yokohama, Japan
| | - Yuka Yagisawa
- Department of Physiology, Tsurumi University School of Dental Medicine, Yokohama, Japan Department of Orthodontics, Tsurumi University School of Dental Medicine, Yokohama, Japan
| | - Huiling Jin
- Cardiovascular Research Institute, Yokohama City University Graduate School of Medicine, Yokohama, Japan
| | - Wenqian Cai
- Cardiovascular Research Institute, Yokohama City University Graduate School of Medicine, Yokohama, Japan
| | - Kenji Suita
- Department of Physiology, Tsurumi University School of Dental Medicine, Yokohama, Japan Cardiovascular Research Institute, Yokohama City University Graduate School of Medicine, Yokohama, Japan
| | - Yasutake Saeki
- Department of Physiology, Tsurumi University School of Dental Medicine, Yokohama, Japan
| | - Takayuki Fujita
- Cardiovascular Research Institute, Yokohama City University Graduate School of Medicine, Yokohama, Japan
| | - Yoshihiro Ishikawa
- Cardiovascular Research Institute, Yokohama City University Graduate School of Medicine, Yokohama, Japan
| | - Satoshi Okumura
- Department of Physiology, Tsurumi University School of Dental Medicine, Yokohama, Japan Cardiovascular Research Institute, Yokohama City University Graduate School of Medicine, Yokohama, Japan
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9
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Donegani E, Paal P, Küpper T, Hefti U, Basnyat B, Carceller A, Bouzat P, van der Spek R, Hillebrandt D. Drug Use and Misuse in the Mountains: A UIAA MedCom Consensus Guide for Medical Professionals. High Alt Med Biol 2016; 17:157-184. [PMID: 27583821 DOI: 10.1089/ham.2016.0080] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Donegani, Enrico, Peter Paal, Thomas Küpper, Urs Hefti, Buddha Basnyat, Anna Carceller, Pierre Bouzat, Rianne van der Spek, and David Hillebrandt. Drug use and misuse in the mountains: a UIAA MedCom consensus guide for medical professionals. High Alt Med Biol. 17:157-184, 2016.-Aims: The aim of this review is to inform mountaineers about drugs commonly used in mountains. For many years, drugs have been used to enhance performance in mountaineering. It is the UIAA (International Climbing and Mountaineering Federation-Union International des Associations d'Alpinisme) Medcom's duty to protect mountaineers from possible harm caused by uninformed drug use. The UIAA Medcom assessed relevant articles in scientific literature and peer-reviewed studies, trials, observational studies, and case series to provide information for physicians on drugs commonly used in the mountain environment. Recommendations were graded according to criteria set by the American College of Chest Physicians. RESULTS Prophylactic, therapeutic, and recreational uses of drugs relevant to mountaineering are presented with an assessment of their risks and benefits. CONCLUSIONS If using drugs not regulated by the World Anti-Doping Agency (WADA), individuals have to determine their own personal standards for enjoyment, challenge, acceptable risk, and ethics. No system of drug testing could ever, or should ever, be policed for recreational climbers. Sponsored climbers or those who climb for status need to carefully consider both the medical and ethical implications if using drugs to aid performance. In some countries (e.g., Switzerland and Germany), administrative systems for mountaineering or medication control dictate a specific stance, but for most recreational mountaineers, any rules would be unenforceable and have to be a personal decision, but should take into account the current best evidence for risk, benefit, and sporting ethics.
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Affiliation(s)
- Enrico Donegani
- 1 Department of Cardiovascular Surgery, Sabah Al-Ahmed Cardiac Center , Al-Amiri Hospital, Kuwait, State of Kuwait
| | - Peter Paal
- 2 Department of Anaesthesiology and Critical Care Medicine, Innsbruck University Hospital , Innsbruck, Austria .,3 Department of Perioperative Medicine, Barts Heart Centre, St. Bartholomew's Hospital, Barts Health NHS Trust, Queen Mary University of London, London, United Kingdom .,4 Perioperative Medicine, St. Bartholomew's Hospital , London, United Kingdom
| | - Thomas Küpper
- 5 Institute of Occupational and Social Medicine, RWTH Aachen University , Aachen, Germany
| | - Urs Hefti
- 6 Department of Orthopedic and Trauma Surgery, Swiss Sportclinic , Bern, Switzerland
| | - Buddha Basnyat
- 7 Oxford University Clinical Research Unit-Nepal , Nepal International Clinic, and Himalayan Rescue, Kathmandu, Nepal
| | - Anna Carceller
- 8 Sports Medicine School, Instituto de Medicina de Montaña y del Deporte (IMMED), Federació d'Entitats Excursionistes (FEEC), University of Barcelona , Barcelona, Spain
| | - Pierre Bouzat
- 9 Department of Anesthesiology and Critical Care, University Hospital, INSERM U1236, Neuroscience Institute, Alps University, Grenoble, France
| | - Rianne van der Spek
- 10 Department of Endocrinology and Metabolism, Academic Medical Center Amsterdam, University of Amsterdam , Amsterdam, The Netherlands
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10
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Ventricular Recovery and Pump Explantation in Patients Supported by Left Ventricular Assist Devices: A Systematic Review. ASAIO J 2016; 62:219-31. [DOI: 10.1097/mat.0000000000000328] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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11
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Ohnuki Y, Umeki D, Mototani Y, Jin H, Cai W, Shiozawa K, Suita K, Saeki Y, Fujita T, Ishikawa Y, Okumura S. Role of cyclic AMP sensor Epac1 in masseter muscle hypertrophy and myosin heavy chain transition induced by β2-adrenoceptor stimulation. J Physiol 2014; 592:5461-75. [PMID: 25344550 DOI: 10.1113/jphysiol.2014.282996] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The predominant isoform of β-adrenoceptor (β-AR) in skeletal muscle is β2-AR and that in the cardiac muscle is β1-AR. We have reported that Epac1 (exchange protein directly activated by cAMP 1), a new protein kinase A-independent cAMP sensor, does not affect cardiac hypertrophy in response to pressure overload or chronic isoproterenol (isoprenaline) infusion. However, the role of Epac1 in skeletal muscle hypertrophy remains poorly understood. We thus examined the effect of disruption of Epac1, the major Epac isoform in skeletal muscle, on masseter muscle hypertrophy induced by chronic β2-AR stimulation with clenbuterol (CB) in Epac1-null mice (Epac1KO). The masseter muscle weight/tibial length ratio was similar in wild-type (WT) and Epac1KO at baseline and was significantly increased in WT after CB infusion, but this increase was suppressed in Epac1KO. CB treatment significantly increased the proportion of myosin heavy chain (MHC) IIb at the expense of that of MHC IId/x in both WT and Epac1KO, indicating that Epac1 did not mediate the CB-induced MHC isoform transition towards the faster isoform. The mechanism of suppression of CB-mediated hypertrophy in Epac1KO is considered to involve decreased activation of Akt signalling. In addition, CB-induced histone deacetylase 4 (HDAC4) phosphorylation on serine 246 mediated by calmodulin kinase II (CaMKII), which plays a role in skeletal muscle hypertrophy, was suppressed in Epac1KO. Our findings suggest that Epac1 plays a role in β2-AR-mediated masseter muscle hypertrophy, probably through activation of both Akt signalling and CaMKII/HDAC4 signalling.
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Affiliation(s)
- Yoshiki Ohnuki
- Department of Physiology, Tsurumi University School of Dental Medicine, Yokohama, 230-8501, Japan
| | - Daisuke Umeki
- Department of Physiology, Tsurumi University School of Dental Medicine, Yokohama, 230-8501, Japan Department of Orthodontics, Tsurumi University School of Dental Medicine, Yokohama, 230-8501, Japan
| | - Yasumasa Mototani
- Department of Physiology, Tsurumi University School of Dental Medicine, Yokohama, 230-8501, Japan
| | - Huiling Jin
- Cardiovascular Research Institute, Yokohama City University Graduate School of Medicine, Yokohama, 236-0004, Japan
| | - Wenqian Cai
- Cardiovascular Research Institute, Yokohama City University Graduate School of Medicine, Yokohama, 236-0004, Japan
| | - Kouichi Shiozawa
- Department of Physiology, Tsurumi University School of Dental Medicine, Yokohama, 230-8501, Japan
| | - Kenji Suita
- Cardiovascular Research Institute, Yokohama City University Graduate School of Medicine, Yokohama, 236-0004, Japan
| | - Yasutake Saeki
- Department of Physiology, Tsurumi University School of Dental Medicine, Yokohama, 230-8501, Japan
| | - Takayuki Fujita
- Cardiovascular Research Institute, Yokohama City University Graduate School of Medicine, Yokohama, 236-0004, Japan
| | - Yoshihiro Ishikawa
- Cardiovascular Research Institute, Yokohama City University Graduate School of Medicine, Yokohama, 236-0004, Japan
| | - Satoshi Okumura
- Department of Physiology, Tsurumi University School of Dental Medicine, Yokohama, 230-8501, Japan Cardiovascular Research Institute, Yokohama City University Graduate School of Medicine, Yokohama, 236-0004, Japan
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Navaratnarajah M, Siedlecka U, Ibrahim M, van Doorn C, Soppa G, Gandhi A, Shah A, Kukadia P, Yacoub MH, Terracciano CM. Impact of combined clenbuterol and metoprolol therapy on reverse remodelling during mechanical unloading. PLoS One 2014; 9:e92909. [PMID: 25268495 PMCID: PMC4181979 DOI: 10.1371/journal.pone.0092909] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2013] [Accepted: 02/26/2014] [Indexed: 01/19/2023] Open
Abstract
Background Clenbuterol (Cl), a β2 agonist, is associated with enhanced myocardial recovery during left ventricular assist device (LVAD) support, and exerts beneficial remodelling effects during mechanical unloading (MU) in rodent heart failure (HF). However, the specific effects of combined Cl+β1 blockade during MU are unknown. Methods and Results We studied the chronic effects (4 weeks) of β2-adrenoceptor (AR) stimulation via Cl (2 mg/kg/day) alone, and in combination with β1-AR blockade using metoprolol ((Met), 250 mg/kg/day), on whole heart/cell structure, function and excitation-contraction (EC) coupling in failing (induced by left coronary artery (LCA) ligation), and unloaded (induced by heterotopic abdominal heart transplantation (HATx)) failing rat hearts. Combined Cl+Met therapy displayed favourable effects in HF: Met enhanced Cl's improvement in ejection fraction (EF) whilst preventing Cl-induced hypertrophy and tachycardia. During MU combined therapy was less beneficial than either mono-therapy. Met, not Cl, prevented MU-induced myocardial atrophy, with increased atrophy occurring during combined therapy. MU-induced recovery of Ca2+ transient amplitude, speed of Ca2+ release and sarcoplasmic reticulum Ca2+ content was enhanced equally by Cl or Met mono-therapy, but these benefits, together with Cl's enhancement of sarcomeric contraction speed, and MU-induced recovery of Ca2+ spark frequency, disappeared during combined therapy. Conclusions Combined Cl+Met therapy shows superior functional effects to mono-therapy in rodent HF, but appears inferior to either mono-therapy in enhancing MU-induced recovery of EC coupling. These results suggest that combined β2-AR simulation +β1-AR blockade therapy is likely to be a safe and beneficial therapeutic HF strategy, but is not as effective as mono-therapy in enhancing myocardial recovery during LVAD support.
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Affiliation(s)
- Manoraj Navaratnarajah
- Harefield Heart Science Centre, Imperial College London, National Heart and Lung Institute, Laboratory of Cellular Electrophysiology, Harefield Hospital, Harefield, Middlesex, United Kingdom
- * E-mail:
| | - Urszula Siedlecka
- Harefield Heart Science Centre, Imperial College London, National Heart and Lung Institute, Laboratory of Cellular Electrophysiology, Harefield Hospital, Harefield, Middlesex, United Kingdom
| | - Michael Ibrahim
- Harefield Heart Science Centre, Imperial College London, National Heart and Lung Institute, Laboratory of Cellular Electrophysiology, Harefield Hospital, Harefield, Middlesex, United Kingdom
| | - Carin van Doorn
- Harefield Heart Science Centre, Imperial College London, National Heart and Lung Institute, Laboratory of Cellular Electrophysiology, Harefield Hospital, Harefield, Middlesex, United Kingdom
| | - Gopal Soppa
- Harefield Heart Science Centre, Imperial College London, National Heart and Lung Institute, Laboratory of Cellular Electrophysiology, Harefield Hospital, Harefield, Middlesex, United Kingdom
| | - Ajay Gandhi
- Harefield Heart Science Centre, Imperial College London, National Heart and Lung Institute, Laboratory of Cellular Electrophysiology, Harefield Hospital, Harefield, Middlesex, United Kingdom
| | - Adarsh Shah
- Harefield Heart Science Centre, Imperial College London, National Heart and Lung Institute, Laboratory of Cellular Electrophysiology, Harefield Hospital, Harefield, Middlesex, United Kingdom
| | - Punam Kukadia
- Harefield Heart Science Centre, Imperial College London, National Heart and Lung Institute, Laboratory of Cellular Electrophysiology, Harefield Hospital, Harefield, Middlesex, United Kingdom
| | - Magdi H. Yacoub
- Harefield Heart Science Centre, Imperial College London, National Heart and Lung Institute, Laboratory of Cellular Electrophysiology, Harefield Hospital, Harefield, Middlesex, United Kingdom
| | - Cesare M. Terracciano
- Harefield Heart Science Centre, Imperial College London, National Heart and Lung Institute, Laboratory of Cellular Electrophysiology, Harefield Hospital, Harefield, Middlesex, United Kingdom
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13
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Pokorný M, Cervenka L, Netuka I, Pirk J, Koňařík M, Malý J. Ventricular assist devices in heart failure: how to support the heart but prevent atrophy? Physiol Res 2014; 63:147-56. [PMID: 24779607 DOI: 10.33549/physiolres.932617] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Ventricular assist devices (VAD) have recently established themselves as an irreplaceable therapeutic modality of terminal heart failure. Because of the worldwide shortage of donors, ventricular assist devices play a key role in modern heart failure therapy. Some clinical data have revealed the possibility of cardiac recovery during VAD application. On the other hand, both clinical and experimental studies indicate the risk of the cardiac atrophy development, especially after prolonged mechanical unloading. Little is known about the specific mechanisms governing the unloading-induced cardiac atrophy and about the exact ultrastructural changes in cardiomyocytes, and even less is known about the ways in which possible therapeutical interventions may affect heart atrophy. One aim of this review was to present important aspects of the development of VAD-related cardiac atrophy in humans and we also review the most significant observations linking clinical data and those derived from studies using experimental models. The focus of this article was to review current methods applied to alleviate cardiac atrophy which follows mechanical unloading of the heart. Out of many pharmacological agents studied, only the selective beta2 agonist clenbuterol has been proved to have a significantly beneficial effect on unloading-induced atrophy. Mechanical means of atrophy alleviation also seem to be effective and promising.
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Affiliation(s)
- M Pokorný
- Department of Cardiovascular Surgery, Institute for Clinical and Experimental Medicine, Prague, Czech Republic.
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14
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Lenneman AJ, Birks EJ. Treatment strategies for myocardial recovery in heart failure. CURRENT TREATMENT OPTIONS IN CARDIOVASCULAR MEDICINE 2014; 16:287. [PMID: 24492922 DOI: 10.1007/s11936-013-0287-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
OPINION STATEMENT Heart failure is a progressive disorder characterized by adverse left ventricular remodeling. Until recently, this has been thought to be an irreversible process. Mechanical unloading with a left ventricular assist device (LVAD), particularly if combined with neurohormonal blockade with heart failure medications, can lead to a reversal of the heart failure phenotype, a process called "reverse remodeling." Reverse remodeling refers to the regression of pathologic myocardial hypertrophy and improvement in LV chamber size that can occur in response to treatment. Myocardial recovery is the sustained normalization of structural, molecular, and hemodynamic changes sufficient to allow explant of the LVAD. Despite the fact that reverse remodeling is commonly seen in LVAD patients in clinical practice, myocardial recovery sufficient to allow device explantation is still rare. Previous experience suggests that young patients with short duration of heart failure and less myocardial fibrosis may be more likely to recover. Alternatively, it may just be that clinicians make a greater effort to recover these subgroups. A combined approach of mechanical unloading with LVADs and pharmacological management, together with regular testing of underlying myocardial function with the pump reduced to a speed at which it is not contributing, can increase the frequency of sustained recovery from heart failure. The goal is to achieve optimal unloading of the myocardium, combined with pharmacologic therapy aimed at promoting reverse remodeling. Myocardial recovery must be considered as a therapeutic target. Clinical variables such as pump speed and blood pressure must be optimized to promote maximal unloading, leading to reverse remodeling and myocardial recovery. Frequent echocardiographic and hemodynamic evaluation of underlying myocardial function must be performed. The combination of LVAD therapy with optimal neurohormonal blockade appears promising as an approach to myocardial recovery. In addition, there is a growing body of translational research which, when combined with LVADs, may further promote more durable recovery. Strategies to thicken the myocardium to enhance the durability of recovery prior to explantation, such as clenbuterol (which induces "physiological hypertrophy"), or intermittently reducing the pump speed to increase myocardial load may be beneficial. Emergence of cardiac stem cells and alternative biologic agents, when added to current therapies, may have a complementary role in promoting and maintaining myocardial recovery. This review will summarize both current strategies and emerging therapies.
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Affiliation(s)
- Andrew J Lenneman
- Division of Cardiovascular Medicine, University of Louisville, Rudd Heart and Lung Center, 201 Abraham Flexner Way, Suite 1001, Louisville, KY, 40202, USA,
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15
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Drakos SG, Charitos EI, Nanas SN, Nanas JN. Ventricular-assist devices for the treatment of chronic heart failure. Expert Rev Cardiovasc Ther 2014; 5:571-84. [PMID: 17489679 DOI: 10.1586/14779072.5.3.571] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The role of ventricular-assist devices in the management of end-stage heart failure is growing. Initially developed as a 'bridge to transplantation', they are now implanted permanently in patients who need cardiac replacement but are not candidates for cardiac transplantation ('destination therapy'). Furthermore, observations from expert centers indicate that a significant proportion of patients under long-term mechanical assistance can be weaned from mechanical circulatory support after significant functional recovery of their native heart ('bridge to recovery'). This review discusses the emerging roles of mechanical circulatory support and their direct implications in clinical practice. Evolution of devices, important aspects of candidate selection, challenging issues in the management of ventricular-assist device patients (infection, device malfunction, anticoagulation-thromboembolic complications, psychosocial issues and cost) and ongoing research targeting sustained myocardial recovery are discussed.
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Affiliation(s)
- Stavros G Drakos
- University of Athens Medical School, 3rd Department of Cardiology, Laiko Hospital, Athens, Greece.
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16
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Abstract
Heart failure is associated with remodeling that consists of adverse cellular, structural, and functional changes in the myocardium. Until recently, this was thought to be unidirectional, progressive, and irreversible. However, irreversibility has been shown to be incorrect because complete or partial reversal can occur that can be marked after myocardial unloading with a left ventricular assist device (LVAD). Patients with chronic advanced heart failure can show near-normalization of nearly all structural abnormalities of the myocardium or reverse remodeling after LVAD support. However, reverse remodeling does not always equate with clinical recovery. The molecular changes occurring after LVAD support are reviewed, both those demonstrated with LVAD unloading alone in patients bridged to transplantation and those occurring in the myocardium of patients who have recovered enough myocardial function to have the device removed. Reverse remodeling may be attributable to a reversal of the pathological mechanisms that occur in remodeling or the generation of new pathways. A reduction in cell size occurs after LVAD unloading, which does not necessarily correlate with improved cardiac function. However, some of the changes in both the cardiac myocyte and the matrix after LVAD support are specific to myocardial recovery. In the myocyte, increases in the cytoskeletal proteins and improvements in the Ca²⁺ handling pathway seem to be specifically associated with myocardial recovery. Changes in the matrix are complex, but excessive scarring appears to limit the ability for recovery, and the degree of fibrosis in the myocardium at the time of implantation may predict the ability to recover.
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Affiliation(s)
- Emma J Birks
- Department of Cardiovascular Medicine, University of Louisville, Louisville, KY, USA.
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17
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Joassard OR, Durieux AC, Freyssenet DG. β2-Adrenergic agonists and the treatment of skeletal muscle wasting disorders. Int J Biochem Cell Biol 2013; 45:2309-21. [PMID: 23845739 DOI: 10.1016/j.biocel.2013.06.025] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Revised: 06/14/2013] [Accepted: 06/26/2013] [Indexed: 02/04/2023]
Abstract
β2-Agonists are traditionally used for the treatment of bronchospasm associated with asthma and the treatment of symptomatic patients with COPD. However, β2-agonists are also powerful anabolic agents that trigger skeletal muscle hypertrophy. Investigating the effects of β2-agonists in skeletal muscle over the past 30 years in different animal models has led to the identification of potential therapeutic applications in several muscle wasting disorders, including neuromuscular diseases, cancer cachexia, sepsis or thermal injury. In these conditions, numerous studies indicate that β2-agonists can attenuate and/or reverse the decrease in skeletal muscle mass and associated weakness in animal models of muscle wasting but also in human patients. The purpose of this review is to present the biological and clinical significance of β2-agonists for the treatment of skeletal muscle wasting. After the description of the molecular mechanisms involved in the hypertrophy and anti-atrophy effect of β2-agonists, we will review the anti-atrophy effects of β2-agonist administration in several animal models and human pathologies associated with or leading to skeletal muscle wasting. This article is part of a Directed Issue entitled: Molecular basis of muscle wasting.
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Affiliation(s)
- Olivier R Joassard
- Laboratoire de Physiologie de l'Exercice, Université de Lyon, F-42023 Saint-Etienne, France
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18
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Abstract
Although cardiac transplant remains the gold standard for the treatment of end-stage heart failure, limited donor organ availability and growing numbers of eligible recipients have increased the demand for alternative therapies. Limitations of first-generation left ventricular assist devices for long-term support of patients with end-stage disease have led to the development of newer second-generation and third-generation pumps, which are smaller, have fewer moving parts, and have shown improved durability, allowing for extended support. The HeartMate II (second generation) and HeartWare (third generation) are 2 devices that have shown great promise as potential alternatives to transplantation in select patients.
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Affiliation(s)
- Michelle Capdeville
- Department of Cardiothoracic Anesthesia, Cleveland Clinic, 9500 Euclid Avenue, J4-331, Cleveland, OH 44195, USA.
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19
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Long-term outcomes of patients bridged to recovery versus patients bridged to transplantation. J Thorac Cardiovasc Surg 2012; 144:190-6. [DOI: 10.1016/j.jtcvs.2012.03.021] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2011] [Revised: 01/17/2012] [Accepted: 03/12/2012] [Indexed: 11/24/2022]
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20
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Wu Y, Feng W, Zhang H, Li S, Wang D, Pan X, Hu S. Ca²+-regulatory proteins in cardiomyocytes from the right ventricle in children with congenital heart disease. J Transl Med 2012; 10:67. [PMID: 22472319 PMCID: PMC3464735 DOI: 10.1186/1479-5876-10-67] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Accepted: 04/02/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Hypoxia and hypertrophy are the most frequent pathophysiological consequence of congenital heart disease (CHD) which can induce the alteration of Ca2+-regulatory proteins and inhibit cardiac contractility. Few studies have been performed to examine Ca2+-regulatory proteins in human cardiomyocytes from the hypertrophic right ventricle with or without hypoxia. METHODS Right ventricle tissues were collected from children with tetralogy of Fallot [n = 25, hypoxia and hypertrophy group (HH group)], pulmonary stenosis [n = 25, hypertrophy group (H group)], or small isolated ventricular septal defect [n = 25, control group (C group)] during open-heart surgery. Paraffin sections of tissues were stained with 3,3'-dioctadecyloxacarbocyanine perchlorate to measure cardiomyocyte size. Expression levels of Ca2+-regulatory proteins [sarcoplasmic reticulum Ca2+-ATPase (SERCA2a), ryanodine receptor (RyR2), sodiumcalcium exchanger (NCX), sarcolipin (SLN) and phospholamban (PLN)] were analysed by means of real-time PCR, western blot, or immunofluorescence. Additionally, phosphorylation level of RyR and PLN and activity of protein phosphatase (PP1) were evaluated using western blot. RESULTS Mild cardiomyocyte hypertrophy of the right ventricle in H and HH groups was confirmed by comparing cardiomyocyte size. A significant reduction of SERCA2a in mRNA (P<0.01) was observed in the HH group compared with the C group. The level of Ser16-phosphorylated PLN was down-regulated (P<0.01) and PP1 was increased (P<0.01) in the HH group compared to that in the C group. CONCLUSIONS The decreased SERCA2a mRNA may be a biomarker of the pathological process in the early stage of cyanotic CHD with the hypertrophic right ventricle. A combination of hypoxia and hypertrophy can induce the adverse effect of PLN-Ser16 dephosphorylation. Increased PP1 could result in the decreased PLN-Ser16 and inhibition of PP1 is a potential therapeutic target for heart dysfunction in pediatrics.
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Affiliation(s)
- Yihe Wu
- State Key Laboratory of Cardiovascular Medicine, Cardiovascular Institute & Fuwai Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
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21
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Duranti G, La Rosa P, Dimauro I, Wannenes F, Bonini S, Sabatini S, Parisi P, Caporossi D. Effects of salmeterol on skeletal muscle cells: metabolic and proapoptotic features. Med Sci Sports Exerc 2012; 43:2259-73. [PMID: 21552152 DOI: 10.1249/mss.0b013e3182223094] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
PURPOSE Salmeterol is a β2-adrenergic receptor agonist widely used for the treatment of asthma and chronic obstructive pulmonary disease. It has been shown that salmeterol is also used at supratherapeutic doses as performance-enhancing substance in sport practice. Although the abuse of β-agonists might determine some adverse effects, the molecular effects of salmeterol on skeletal muscle cells remain unclear. METHODS We evaluated the effects of salmeterol (0.1-10 μM) on both proliferative and differentiated rat L6C5 and mouse C2C12 skeletal muscle cell lines. The metabolic effects were evaluated by glyceraldehyde phosphate dehydrogenase, lactate dehydrogenase, citrate synthase, 3-OH acyl-CoA dehydrogenase, and alanine transglutaminase activities. Cytotoxic and apoptotic effects were analyzed by 3-(4,5-dimethylthiazol-1)-5-(3-carboxymeth-oxyphenyl)-2H-tetrazolium, trypan blue exclusion assay, terminal deoxynucleotidyl transferase dUTP nick end labeling assay, Western blot analysis, and immunofluorescence staining. RESULTS We showed that salmeterol reduced the growth rate of proliferating cells in a dose- and time-dependent manner (6-48 h). An increase in oxidative metabolism was found after 6 h in C2C12 and L6C5 myoblasts and in C2C12 myotubes with respect to control cells, while in L6C5 myotubes, anaerobic metabolism prevailed. Exposure of myoblasts and myotubes for 48 and 72 h at high salmeterol concentrations induced apoptosis by the activation of the intrinsic apoptotic pathway, as confirmed by the modulation of the apoptotic proteins Bcl-xL, caspase-9, and poly (ADP-ribose) polymerase and by the cytoplasmic release of Smac/DIABLO. CONCLUSIONS Altogether, our results demonstrate that short-term supratherapeutic salmeterol exposure increased oxidative metabolic pathways on skeletal muscle cells, whereas prolonged treatment inhibits cell growth and exerts either a cytostatic or a proapoptotic effect in a time- and dose-dependent way.
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Affiliation(s)
- Guglielmo Duranti
- Department of Health Sciences, University of Rome Foro Italico, Rome, Italy.
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22
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Hatch F, Lancaster MK, Jones SA. Aging is a primary risk factor for cardiac arrhythmias: disruption of intracellular Ca2+ regulation as a key suspect. Expert Rev Cardiovasc Ther 2012; 9:1059-67. [PMID: 21878050 DOI: 10.1586/erc.11.112] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Aging is an inevitable time-dependent progression associated with a functional decline of the cardiovascular system even in 'healthy' individuals. Age positively correlates with an increasing risk of cardiac problems including arrhythmias. Not only the prevalence but also the severity of arrhythmias escalates with age. The reasons for this are multifactorial but dysregulation of intracellular calcium within the heart is likely to play a key role in initiating and perpetuating these life-threatening events. We now know that several aspects of cardiac calcium regulation significantly change with advancing age - changes that could produce electrical instability. Further development of knowledge of the mechanisms underlying these changes will allow us to reduce what currently is an inevitable increase in the incidence of arrhythmias in the elderly.
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Affiliation(s)
- Fiona Hatch
- Biological Sciences and HYMS, University of Hull, Kingston-Upon-Hull, UK
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23
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The paradox of left ventricular assist device unloading and myocardial recovery in end-stage dilated cardiomyopathy: implications for heart failure in the elderly. Heart Fail Rev 2012; 17:615-33. [DOI: 10.1007/s10741-012-9300-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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Jiang GL, Gu YD, Zhang LY, Shen LY, Yu C, Xu JG. Randomized, double-blind, and placebo-controlled trial of clenbuterol in denervated muscle atrophy. ISRN PHARMACEUTICS 2011; 2011:981254. [PMID: 22389867 PMCID: PMC3263717 DOI: 10.5402/2011/981254] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/01/2011] [Accepted: 06/21/2011] [Indexed: 12/21/2022]
Abstract
Objectives. β2-adrenergic agonists, such as clenbuterol, have been shown to promote the hypertrophy of healthy skeletal muscles and to ameliorate muscle wasting in a few pathological conditions in both animals and humans. We intended to investigate the clinical efficacy of clenbuterol on attenuating denervation-induced muscle atrophy. Methods. A double-blind, placebo-controlled, parallel, and randomized trial was employed. 71 patients, suffering from brachial plexus injuries, were given either clenbuterol (60 μg, bid) or placebo for 3 months. Before and at the end of the study, patients were given physical examinations, biopsies of biceps brachii, electromyograms (EMGs), and other laboratory tests. Results. Compared with placebo treatment, clenbuterol significantly mitigated the decreases in cross-sectional areas of type I and II muscle fibers and alleviated the reduction in fibrillation potential amplitudes, without any adverse effects. Conclusions. Clenbuterol safely ameliorated denervated muscle atrophy in this cohort; thus larger clinical studies are encouraged for this or other β2 agonists on denervation-induced muscle atrophy.
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Affiliation(s)
- Guang-Liang Jiang
- Department of Hand Surgery, Huashan Hospital of Fudan University, Shanghai 200040, China
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25
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Choucair-Jaafar N, Beetz N, Gilsbach R, Yalcin I, Waltisperger E, Freund-Mercier MJ, Monassier L, Hein L, Barrot M. Cardiovascular effects of chronic treatment with a β2-adrenoceptor agonist relieving neuropathic pain in mice. Neuropharmacology 2011; 61:51-60. [PMID: 21352833 DOI: 10.1016/j.neuropharm.2011.02.015] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2010] [Revised: 02/15/2011] [Accepted: 02/15/2011] [Indexed: 01/06/2023]
Abstract
Neuropathic pain is often a chronic condition, disabling and difficult to treat. Using a murine model of neuropathic pain induced by placing a polyethylene cuff around the main branch of the sciatic nerve, we have shown that chronic treatment with β-AR agonists is effective against neuropathic allodynia. β-mimetics are widely used against asthma and chronic obstructive pulmonary disease and may offer an interesting option for neuropathic pain management. The most prominent adverse effects of chronic treatment with β-mimetics are cardiovascular. In this study, we compared the action of low doses of the selective β(2)-AR agonist terbutaline and of a high dose of the mixed β(1)/β(2)-AR agonist isoproterenol on cardiovascular parameters in a neuropathic pain context. Isoproterenol was used as a positive control for some heart-related changes. Cardiac functions were studied by echocardiography, hemodynamic measurements, histological analysis of fibrosis and cardiac hypertrophy, and by quantitative real time PCR analysis of atrial natriuretic peptide (Nppa), periostin (Postn), connective tissue growth factor (Ctgf) and β-myosin heavy chain (Myh7). Our data show that a chronic treatment with the β(2)-AR agonist terbutaline at low antiallodynic dose does not affect cardiovascular parameters, whereas the mixed β(1)/β(2)-AR agonist isoproterenol induces cardiac hypertrophy. These data suggest that low doses of β(2)-AR agonists may provide a suitable treatment with rare side effects in neuropathic pain management. This study conducted in an animal model requires clinical confirmation in humans.
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Affiliation(s)
- Nada Choucair-Jaafar
- Institut des Neurosciences Cellulaires et Intégratives, Centre National de la Recherche Scientifique, 21 rue René Descartes, 67084 Strasbourg cedex, France
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26
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Birks EJ, George RS, Hedger M, Bahrami T, Wilton P, Bowles CT, Webb C, Bougard R, Amrani M, Yacoub MH, Dreyfus G, Khaghani A. Reversal of Severe Heart Failure With a Continuous-Flow Left Ventricular Assist Device and Pharmacological Therapy. Circulation 2011; 123:381-90. [DOI: 10.1161/circulationaha.109.933960] [Citation(s) in RCA: 314] [Impact Index Per Article: 24.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background—
We have previously shown that a specific combination of drug therapy and left ventricular assist device unloading results in significant myocardial recovery, sufficient to allow pump removal, in two thirds of patients with dilated cardiomyopathy receiving a Heartmate I pulsatile device. However, this protocol has not been used with nonpulsatile devices.
Methods and Results—
We report the results of a prospective study of 20 patients who received a combination of angiotensin-converting enzymes, β-blockers, angiotensin II inhibitors, and aldosterone antagonists followed by the β
2
-agonist clenbuterol and were regularly tested (echocardiograms, exercise tests, catheterizations) with the pump at low speed. Before left ventricular assist device insertion, patient age was 35.2±12.6 years (16 male patients), patients were on 2.0±0.9 inotropes, 7 (35) had an intra-aortic balloon pump, 2 were hemofiltered, 2 were ventilated, 3 had a prior Levitronix device, and 1 had extracorporeal membrane oxygenation. Cardiac index was 1.39±0.43 L · min
−1
· m
−2
, pulmonary capillary wedge pressure was 31.5±5.7 mm Hg, and heart failure history was 3.4±3.5 years. One patient was lost to follow-up and died after 240 days of support. Of the remaining 19 patients, 12 (63.2) were explanted after 286±97 days. Eight had symptomatic heart failure for ≤6 months and 4 for >6 months (48 to 132 months). Before explantation, at low flow for 15 minutes, ejection fraction was 70±7, left ventricular end-diastolic diameter was 48.6±5.7 mm, left ventricular end-systolic diameter was 32.3±5.7 mm, mV̇
o
2
was 21.6±4 mL · kg
−1
· min
−1
, pulmonary capillary wedge pressure was 5.9±4.6 mm Hg, and cardiac index was 3.6±0.6 L · min
−1
· m
−2
. Estimated survival without heart failure recurrence was 83.3 at 1 and 3 years. After a 430.7±337.1-day follow-up, surviving explants had an ejection fraction of 58.1±13.8, left ventricular end-diastolic diameter of 59.0±9.3 mm, left ventricular end-systolic diameter of 42.0±10.7 mm, and mV̇
o
2
of 22.6±5.3 mL · kg
−1
· min
−1
.
Conclusions—
Reversal of end-stage heart failure secondary to nonischemic cardiomyopathy can be achieved in a substantial proportion of patients with nonpulsatile flow through the use of a combination of mechanical and pharmacological therapy.
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Affiliation(s)
- Emma J. Birks
- From the Royal Brompton and Harefield NHS Foundation Trust (E.J.B., R.S.G., M.H., T.B., P.W., C.T.B., C.W., R.B., M.A., G.D., A.K.) and Heart Science Centre, Imperial College (E.J.B., R.S.G., C.T.B., M.H.Y.), Harefield, Middlesex, UK, and University of Louisville, Louisville, KY (E.J.B.)
| | - Robert S. George
- From the Royal Brompton and Harefield NHS Foundation Trust (E.J.B., R.S.G., M.H., T.B., P.W., C.T.B., C.W., R.B., M.A., G.D., A.K.) and Heart Science Centre, Imperial College (E.J.B., R.S.G., C.T.B., M.H.Y.), Harefield, Middlesex, UK, and University of Louisville, Louisville, KY (E.J.B.)
| | - Mike Hedger
- From the Royal Brompton and Harefield NHS Foundation Trust (E.J.B., R.S.G., M.H., T.B., P.W., C.T.B., C.W., R.B., M.A., G.D., A.K.) and Heart Science Centre, Imperial College (E.J.B., R.S.G., C.T.B., M.H.Y.), Harefield, Middlesex, UK, and University of Louisville, Louisville, KY (E.J.B.)
| | - Toufan Bahrami
- From the Royal Brompton and Harefield NHS Foundation Trust (E.J.B., R.S.G., M.H., T.B., P.W., C.T.B., C.W., R.B., M.A., G.D., A.K.) and Heart Science Centre, Imperial College (E.J.B., R.S.G., C.T.B., M.H.Y.), Harefield, Middlesex, UK, and University of Louisville, Louisville, KY (E.J.B.)
| | - Penny Wilton
- From the Royal Brompton and Harefield NHS Foundation Trust (E.J.B., R.S.G., M.H., T.B., P.W., C.T.B., C.W., R.B., M.A., G.D., A.K.) and Heart Science Centre, Imperial College (E.J.B., R.S.G., C.T.B., M.H.Y.), Harefield, Middlesex, UK, and University of Louisville, Louisville, KY (E.J.B.)
| | - Christopher T. Bowles
- From the Royal Brompton and Harefield NHS Foundation Trust (E.J.B., R.S.G., M.H., T.B., P.W., C.T.B., C.W., R.B., M.A., G.D., A.K.) and Heart Science Centre, Imperial College (E.J.B., R.S.G., C.T.B., M.H.Y.), Harefield, Middlesex, UK, and University of Louisville, Louisville, KY (E.J.B.)
| | - Carole Webb
- From the Royal Brompton and Harefield NHS Foundation Trust (E.J.B., R.S.G., M.H., T.B., P.W., C.T.B., C.W., R.B., M.A., G.D., A.K.) and Heart Science Centre, Imperial College (E.J.B., R.S.G., C.T.B., M.H.Y.), Harefield, Middlesex, UK, and University of Louisville, Louisville, KY (E.J.B.)
| | - Robert Bougard
- From the Royal Brompton and Harefield NHS Foundation Trust (E.J.B., R.S.G., M.H., T.B., P.W., C.T.B., C.W., R.B., M.A., G.D., A.K.) and Heart Science Centre, Imperial College (E.J.B., R.S.G., C.T.B., M.H.Y.), Harefield, Middlesex, UK, and University of Louisville, Louisville, KY (E.J.B.)
| | - Mohammed Amrani
- From the Royal Brompton and Harefield NHS Foundation Trust (E.J.B., R.S.G., M.H., T.B., P.W., C.T.B., C.W., R.B., M.A., G.D., A.K.) and Heart Science Centre, Imperial College (E.J.B., R.S.G., C.T.B., M.H.Y.), Harefield, Middlesex, UK, and University of Louisville, Louisville, KY (E.J.B.)
| | - Magdi H. Yacoub
- From the Royal Brompton and Harefield NHS Foundation Trust (E.J.B., R.S.G., M.H., T.B., P.W., C.T.B., C.W., R.B., M.A., G.D., A.K.) and Heart Science Centre, Imperial College (E.J.B., R.S.G., C.T.B., M.H.Y.), Harefield, Middlesex, UK, and University of Louisville, Louisville, KY (E.J.B.)
| | - Gilles Dreyfus
- From the Royal Brompton and Harefield NHS Foundation Trust (E.J.B., R.S.G., M.H., T.B., P.W., C.T.B., C.W., R.B., M.A., G.D., A.K.) and Heart Science Centre, Imperial College (E.J.B., R.S.G., C.T.B., M.H.Y.), Harefield, Middlesex, UK, and University of Louisville, Louisville, KY (E.J.B.)
| | - Asghar Khaghani
- From the Royal Brompton and Harefield NHS Foundation Trust (E.J.B., R.S.G., M.H., T.B., P.W., C.T.B., C.W., R.B., M.A., G.D., A.K.) and Heart Science Centre, Imperial College (E.J.B., R.S.G., C.T.B., M.H.Y.), Harefield, Middlesex, UK, and University of Louisville, Louisville, KY (E.J.B.)
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Clenbuterol Induces Cardiac Myocyte Hypertrophy via Paracrine Signalling and Fibroblast-derived IGF-1. J Cardiovasc Transl Res 2010; 3:688-95. [DOI: 10.1007/s12265-010-9199-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2010] [Accepted: 05/27/2010] [Indexed: 01/08/2023]
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Abstract
Patients with chronic advanced heart failure unloaded by left ventricular assist devices can show improvement in their myocardial function and some can show "reverse remodeling" to the extent that their myocardial function improves sufficiently for the device to be removed. Furthermore, recent data suggest that combining mechanical support with adjuvant drug therapy can increase the rate and proportion of recovery as well as its durability. This article will review the evidence for myocardial recovery in patients with chronic heart failure and whether it is a "real" phenomenon.
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Affiliation(s)
- Emma J Birks
- University of Louisville and Jewish Hospital, Louisville, KY 40202, USA.
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Abstract
The introduction of the heart lung machine more than 50 years ago proved in principle that heart function can be replaced, albeit for short periods. This was followed by attempts to produce total or partial artificial hearts that could function for prolonged periods of time. Progress in this field has been intermittent but has accelerated considerably in the past 10 years, with ventricular assist devices (VADs) reaching an impressive degree of sophistication and complexity owing to the contributions from clinicians, engineers, scientists, industrialists, and others. This review describes the currently available types of VADs, their current clinical use, the patient selection process, the trend toward use of VADs in patients with less severe heart failure, and the use of VADs for myocardial recovery in combination with novel pharmacological strategies, gene therapy, and cell therapy.
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Affiliation(s)
- Cesare M Terracciano
- Harefield Heart Science Centre, Imperial College London, Harefield, Middlesex UB9 6JH, UK
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Ishikawa C, Ogawa T, Ikawa T, Yamane A. Effects of clenbuterol, a β₂-adrenergic agonist, on sizes of masseter, temporalis, digastric, and tongue muscles. Open Dent J 2009; 3:191-6. [PMID: 19812707 PMCID: PMC2757670 DOI: 10.2174/1874210600903010191] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2009] [Revised: 07/02/2009] [Accepted: 07/31/2009] [Indexed: 11/22/2022] Open
Abstract
We compared the hypertrophic effects of clenbuterol, a β2-adrenergic agonist, on the masseter, digastric, and temporalis with those on the tongue, tibialis anterior, soleus, diaphragm, and heart. The weights of masseter, digastric and temporalis in the clenbuterol group were 36 ~ 56% greater than those in the control group, whereas those of the tibialis anterior, diaphragm, and heart weights in the clenbuterol group were 9 ~ 33% greater than those in the control group. No significant difference in the weights of the soleus and tongue was found between the control and clenbuterol groups. Taken together with our present and previously reported results, it is suggested that the hypertrophic effects of clenbuterol on the masseter, digastric, and temporalis are greater than those on the limb, trunk, and heart.
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Affiliation(s)
- Chieko Ishikawa
- Department of Removable Prosthodontics, Tsurumi University School of Dental Medicine, 2-1-3 Tsurumi, Tsurumi-ku, Yokohama 230-8501, Japan
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Chronic treatment with clenbuterol modulates endothelial progenitor cells and circulating factors in a murine model of cardiomyopathy. J Cardiovasc Transl Res 2009; 2:182-90. [PMID: 20559986 DOI: 10.1007/s12265-009-9089-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2008] [Accepted: 01/27/2009] [Indexed: 10/21/2022]
Abstract
The purpose of this study was to determine the effects of chronic treatment with the beta 2 adrenergic receptor agonist clenbuterol on endothelial progenitor cells (EPC) in a well-characterized model of heart failure, the muscle LIM protein knockout (MLP(-/-)) mouse. MLP(-/-) mice were treated daily with clenbuterol (2 mg/kg) or saline subcutaneously for 6 weeks. Clenbuterol led to a 30% increase in CD31(+) cells in the bone marrow of MLP(-/-) heart failure mice (p < 0.004). Clenbuterol did not improve ejection fraction. Clenbuterol treatment in MLP(-/-) mice was associated with significant changes in the following circulating factors: tissue inhibitor of metalloproteinase-type 1, leukemia inhibitory factor 1, C-reactive protein, apolipoprotein A1, fibroblast growth factor 2, serum glutamic oxaloacetic transaminase, macrophage-derived chemokine, and monocyte chemoattractant protein-3. Clenbuterol treatment in the MLP(-/-) model of heart failure did not rescue heart function, yet did increase CD31(+) cells in the bone marrow. This is the first evidence that a beta 2 agonist increases EPC proliferation in the bone marrow in a preclinical model of heart failure.
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Lara-Pezzi E, Terracciano CMN, Soppa GKR, Smolenski RT, Felkin LE, Yacoub MH, Barton PJR. A gene expression profile of the myocardial response to clenbuterol. J Cardiovasc Transl Res 2009; 2:191-7. [PMID: 20559987 DOI: 10.1007/s12265-009-9097-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2009] [Accepted: 02/25/2009] [Indexed: 01/08/2023]
Abstract
Clenbuterol is currently being used as part of a clinical trial into a novel therapeutic approach for the treatment of end-stage heart failure. The purpose of this study was to determine the global pattern of myocardial gene expression in response to clenbuterol and to identify novel targets and pathways involved. Rats were treated with clenbuterol (n = 6) or saline (n = 6) for periods of 1, 3, 9, or 28 days. Rats treated for 28 days were also subject to continuous electrocardiogram analysis using implantable telemetry. RNA was extracted from rats at days 1 and 28 and used from microarray analysis, and further samples from rats at days 1, 3, 9, and 28 were used for analysis by real-time polymerase chain reaction. Clenbuterol treatment induced rapid development of cardiac hypertrophy with increased muscle mass at day 1 and elevated heart rate and QT interval throughout the 28-day period. Microarray analysis revealed a marked but largely transitory change in gene expression with 1,423 genes up-regulated and 964 genes down-regulated at day 1. Up-regulated genes revealed an unexpected association with angiogenesis and integrin-mediated cell adhesion and signaling. Moreover, direct treatment of endothelial cells cultured in vitro resulted in increased cell proliferation and tube formation. Our data show that clenbuterol treatment is associated with rapid cardiac hypertrophy and identify angiogenesis and integrin signaling as novel pathways of clenbuterol action. The data have implications both for our understanding of the physiologic hypertrophy induced by clenbuterol and for treatment of heart failure.
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Affiliation(s)
- Enrique Lara-Pezzi
- Harefield Heart Science Centre, National Heart and Lung Institute, Imperial College, Hill End Road, Harefield, Middlesex, UB9 6JH, UK
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Ryall JG, Lynch GS. The potential and the pitfalls of β-adrenoceptor agonists for the management of skeletal muscle wasting. Pharmacol Ther 2008; 120:219-32. [DOI: 10.1016/j.pharmthera.2008.06.003] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2008] [Accepted: 06/04/2008] [Indexed: 01/08/2023]
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Malliaras KG, Terrovitis JV, Drakos SG, Nanas JN. Reverse cardiac remodeling enabled by mechanical unloading of the left ventricle. J Cardiovasc Transl Res 2008; 2:114-25. [PMID: 20559975 DOI: 10.1007/s12265-008-9057-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2008] [Accepted: 09/05/2008] [Indexed: 01/28/2023]
Abstract
Cardiac remodeling is a characteristic and basic component of heart failure progression and is associated with a poor prognosis. Attenuating or reversing remodeling is an accepted goal of heart failure therapy. Cardiac mechanical support with left ventricular assist devices, in addition to its established role as "bridge to transplantation" or "destination therapy" in patients not eligible for cardiac transplantation, offers the potential for significant and sustained myocardial recovery through reverse remodeling. This review discusses the emerging role of left ventricular assist devices as a "bridge to recovery". Clinical and basic aspects of cardiac remodeling and cardiac reverse remodeling enabled by mechanical unloading, potential candidates for this modality of treatment as well as unresolved issues regarding the use of mechanical circulatory support as a bridge to recovery are discussed.
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Siedlecka U, Arora M, Kolettis T, Soppa GKR, Lee J, Stagg MA, Harding SE, Yacoub MH, Terracciano CMN. Effects of clenbuterol on contractility and Ca2+ homeostasis of isolated rat ventricular myocytes. Am J Physiol Heart Circ Physiol 2008; 295:H1917-26. [PMID: 18775853 DOI: 10.1152/ajpheart.00258.2008] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Clenbuterol, a compound classified as a beta2-adrenoceptor (AR) agonist, has been employed in combination with left ventricular assist devices (LVADs) to treat patients with severe heart failure. Previous studies have shown that chronic administration of clenbuterol affects cardiac excitation-contraction coupling. However, the acute effects of clenbuterol and the signaling pathway involved remain undefined. We investigated the acute effects of clenbuterol on isolated ventricular myocyte sarcomere shortening, Ca2+ transients, and L-type Ca2+ current and compared these effects to two other clinically used beta2-AR agonists: fenoterol and salbutamol. Clenbuterol (30 microM) produced a negative inotropic response, whereas fenoterol showed a positive inotropic response. Salbutamol had no significant effects. Clenbuterol reduced Ca2+ transient amplitude and L-type Ca2+ current. Selective beta1-AR blockade did not affect the action of clenbuterol on sarcomere shortening but significantly reduced contractility in the presence of fenoterol and salbutamol (P < 0.05). Incubation with 2 microg/ml pertussis toxin significantly reduced the negative inotropic effects of 30 microM clenbuterol. In addition, overexpression of inhibitory G protein (Gi) by adenoviral transfection induced a stronger clenbuterol-mediated negative inotropic effect, suggesting the involvement of the Gi protein. We conclude that clenbuterol does not increase and, at high concentrations, significantly depresses contractility of isolated ventricular myocytes, an effect not seen with fenoterol or salbutamol. In its negative inotropism, clenbuterol predominantly acts through Gi, and the consequent downstream signaling pathways activation may explain the beneficial effects observed during chronic administration of clenbuterol in patients treated with LVADs.
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Affiliation(s)
- U Siedlecka
- Heart Science Centre, National Heart & Lung Institute, Imperial College, London, United Kingdom
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36
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Lynch GS, Ryall JG. Role of beta-adrenoceptor signaling in skeletal muscle: implications for muscle wasting and disease. Physiol Rev 2008; 88:729-67. [PMID: 18391178 DOI: 10.1152/physrev.00028.2007] [Citation(s) in RCA: 295] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The importance of beta-adrenergic signaling in the heart has been well documented, but it is only more recently that we have begun to understand the importance of this signaling pathway in skeletal muscle. There is considerable evidence regarding the stimulation of the beta-adrenergic system with beta-adrenoceptor agonists (beta-agonists). Although traditionally used for treating bronchospasm, it became apparent that some beta-agonists could increase skeletal muscle mass and decrease body fat. These so-called "repartitioning effects" proved desirable for the livestock industry trying to improve feed efficiency and meat quality. Studying beta-agonist effects on skeletal muscle has identified potential therapeutic applications for muscle wasting conditions such as sarcopenia, cancer cachexia, denervation, and neuromuscular diseases, aiming to attenuate (or potentially reverse) the muscle wasting and associated muscle weakness, and to enhance muscle growth and repair after injury. Some undesirable cardiovascular side effects of beta-agonists have so far limited their therapeutic potential. This review describes the physiological significance of beta-adrenergic signaling in skeletal muscle and examines the effects of beta-agonists on skeletal muscle structure and function. In addition, we examine the proposed beneficial effects of beta-agonist administration on skeletal muscle along with some of the less desirable cardiovascular effects. Understanding beta-adrenergic signaling in skeletal muscle is important for identifying new therapeutic targets and identifying novel approaches to attenuate the muscle wasting concomitant with many diseases.
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Affiliation(s)
- Gordon S Lynch
- Basic and Clinical Myology Laboratory, Department of Physiology, The University of Melbourne, Victoria, Australia.
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Huang YC, Khait L, Birla RK. Modulating the Functional Performance of Bioengineered Heart Muscle Using Growth Factor Stimulation. Ann Biomed Eng 2008; 36:1372-82. [DOI: 10.1007/s10439-008-9517-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2007] [Accepted: 05/12/2008] [Indexed: 10/22/2022]
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Soppa GKR, Lee J, Stagg MA, Felkin LE, Barton PJR, Siedlecka U, Youssef S, Yacoub MH, Terracciano CMN. Role and possible mechanisms of clenbuterol in enhancing reverse remodelling during mechanical unloading in murine heart failure. Cardiovasc Res 2008; 77:695-706. [PMID: 18178572 PMCID: PMC5436743 DOI: 10.1093/cvr/cvm106] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Aims Combined left ventricular assist device (LVAD) and pharmacological therapy has been proposed to favour myocardial recovery in patients with end-stage heart failure (HF). Clenbuterol (Clen), a β2-adrenoceptor (β2-AR) agonist, has been used as a part of this strategy. In this study, we investigated the direct effects of clenbuterol on unloaded myocardium in HF. Methods and results Left coronary artery ligation or sham operation was performed in male Lewis rats. After 4–6 weeks, heterotopic abdominal transplantation of the failing hearts into normal recipients was performed to induce LV unloading (UN). Recipient rats were treated with saline (Sal) or clenbuterol (2 mg/kg/day) via osmotic minipumps (HF + UN + Sal or HF + UN + Clen) for 7 days. Non-transplanted HF animals were treated with Sal (Sham + Sal, HF + Sal) or clenbuterol (HF + Clen). LV myocytes were isolated and studied using optical, fluorescence, and electrophysiological techniques. Clenbuterol treatment improved in vivo LV function measured with echocardiography (LVEF (%): HF 35.9 ± 2 [16], HF + Clen 52.1 ± 1.4 [16]; P < 0.001; mean ± SEM [n]). In combination with unloading, clenbuterol increased sarcomere shortening (amplitude (µm): HF + UN + Clen 0.1 ± 0.01 [50], HF + UN + Sal 0.07 ± 0.01 [38]; P < 0.001) by normalizing the depressed myofilament sensitivity to Ca2+ (slope of the linear relationship between Ca2+ transient and sarcomere shortening hysteresis loop during relaxation (μm/ratio unit): HF + UN + Clen 2.13 ± 0.2 [52], HF + UN + Sal 1.42 ± 0.13 [38]; P < 0.05). Conclusion Clenbuterol treatment of failing rat hearts, alone or in combination with mechanical unloading, improves LV function at the whole-heart and cellular levels by affecting cell morphology, excitation–contraction coupling, and myofilament sensitivity to calcium. This study supports the use of this drug in the strategy to enhance recovery in HF patients treated with LVADs and also begins to elucidate some of the possible cellular mechanisms responsible for the improvement in LV function.
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Affiliation(s)
- Gopal K R Soppa
- Heart Science Centre, Imperial College London, National Heart and Lung Institute, Laboratory of Cellular Electrophysiology, Harefield Hospital, Harefield, Middlesex, UK
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Mueller J, Wallukat G. Patients who Have Dilated Cardiomyopathy Must Have a Trial of Bridge to Recovery (Pro). Heart Fail Clin 2007; 3:299-315. [DOI: 10.1016/j.hfc.2007.05.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Drakos SG, Terrovitis JV, Anastasiou-Nana MI, Nanas JN. Reverse remodeling during long-term mechanical unloading of the left ventricle. J Mol Cell Cardiol 2007; 43:231-42. [PMID: 17651751 DOI: 10.1016/j.yjmcc.2007.05.020] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2007] [Revised: 05/09/2007] [Accepted: 05/29/2007] [Indexed: 01/08/2023]
Abstract
A significant proportion of patients placed on long-term mechanical circulatory support for end-stage heart failure can be weaned from mechanical assistance after functional recovery of their native heart ("bridge to recovery"). The pathophysiological mechanisms implicated in reverse remodeling that cause a sustained functional myocardial recovery have recently become the subject of intensive research, expected to provide information with a view to accurately identify reliable prognostic indicators of recovery. In addition, this kind of information will enable changes in the strategy of myocardial recovery by modifying the duration and scale of the unloading regimen or by combining it with other treatments that promote reverse remodeling.
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Affiliation(s)
- Stavros G Drakos
- 3rd Cardiology Department, University of Athens School of Medicine, 24 Makedonias, 104 33, Athens, Greece
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41
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Abstract
Chronic heart failure is a debilitating condition with significant morbidity, mortality and an increasing economic burden. The past 20 years have witnessed great strides in both medical and device-based therapies for heart failure. Central to these developments has been the ability to favorably reverse the chronic processes by which the failing heart remodels. In addition to pharmacotherapies, such as beta-blockade, and inhibition of the renin-angiotensin-aldosterone system, surgical remodeling, containment devices and new methods to restore synchronous contraction have been added to the armamentarium, in some instances, providing clear improvement to both symptoms and mortality. In more advanced stages of heart failure, left ventricular-assist devices provide marked unloading of the failing ventricle and such therapy has provided unique insights into the molecular and cellular mechanisms underlying reverse remodeling, given the immediate access to cardiac tissue. Genetic and cellular approaches, as well as new small molecule targets, may provide future avenues for reverse remodeling of the failing heart, improving symptoms and disease outcome.
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Affiliation(s)
- James O Mudd
- Johns Hopkins Medical Institutions, Division of Cardiology, Department of Medicine, Baltimore, MD, USA.
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42
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Surgical Treatment. CARDIOVASCULAR MEDICINE 2007. [DOI: 10.1007/978-1-84628-715-2_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Birks EJ, Tansley PD, Hardy J, George RS, Bowles CT, Burke M, Banner NR, Khaghani A, Yacoub MH. Left ventricular assist device and drug therapy for the reversal of heart failure. N Engl J Med 2006; 355:1873-84. [PMID: 17079761 DOI: 10.1056/nejmoa053063] [Citation(s) in RCA: 622] [Impact Index Per Article: 34.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND In patients with severe heart failure, prolonged unloading of the myocardium with the use of a left ventricular assist device has been reported to lead to myocardial recovery in small numbers of patients for varying periods of time. Increasing the frequency and durability of myocardial recovery could reduce or postpone the need for subsequent heart transplantation. METHODS We enrolled 15 patients with severe heart failure due to nonischemic cardiomyopathy and with no histologic evidence of active myocarditis. All had markedly reduced cardiac output and were receiving inotropes. The patients underwent implantation of left ventricular assist devices and were treated with lisinopril, carvedilol, spironolactone, and losartan to enhance reverse remodeling. Once regression of left ventricular enlargement had been achieved, the beta2-adrenergic-receptor agonist clenbuterol was administered to prevent myocardial atrophy. RESULTS Eleven of the 15 patients had sufficient myocardial recovery to undergo explantation of the left ventricular assist device a mean (+/-SD) of 320+/-186 days after implantation of the device. One patient died of intractable arrhythmias 24 hours after explantation; another died of carcinoma of the lung 27 months after explantation. The cumulative rate of freedom from recurrent heart failure among the surviving patients was 100% and 88.9% 1 and 4 years after explantation, respectively. The quality of life as assessed by the Minnesota Living with Heart Failure Questionnaire score at 3 years was nearly normal. Fifty-nine months after explantation, the mean left ventricular ejection fraction was 64+/-12%, the mean left ventricular end-diastolic diameter was 59.4+/-12.1 mm, the mean left ventricular end-systolic diameter was 42.5+/-13.2 mm, and the mean maximal oxygen uptake with exercise was 26.3+/-6.0 ml per kilogram of body weight per minute. CONCLUSIONS In this single-center study, we found that sustained reversal of severe heart failure secondary to nonischemic cardiomyopathy could be achieved in selected patients with the use of a left ventricular assist device and a specific pharmacologic regimen.
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Affiliation(s)
- Emma J Birks
- Royal Brompton and Harefield National Health Service Trust, Harefield, Middlesex, United Kingdom
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Flecher E, Joudinaud T, Grinda JM. Histoire de l'assistance circulatoire mécanique et du cœur artificiel. ACTA ACUST UNITED AC 2006; 131:473-8. [PMID: 16530155 DOI: 10.1016/j.anchir.2005.12.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2005] [Accepted: 12/19/2005] [Indexed: 11/30/2022]
Abstract
The impact of heart failure on patients and economical burden on health insurance resources is increasing. Cardiac transplantation is still the primary treatment for patients who are in end stage heart failure. The development of artificial hearts (total and partial) was implemented by the discrepancy between the scarcity of available donors and the importance of waiting lists for cardiac transplantation. The technical progresses achieved since the first works of Kolff in 1957 now allow these patients to have their circulation restored and go home to wait for their transplantation. The encouraging results of the artificial heart and the miniaturization of these devices allow them to be considered as a possible destination therapy for patients not eligible for cardiac transplantation.
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Affiliation(s)
- E Flecher
- Service de chirurgie cardiovasculaire, hôpital européen Georges-Pompidou, 20-40, rue Leblanc, 75015 Paris, France.
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45
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Akutsu S, Shimada A, Yamane A. Transforming growth factor betas are upregulated in the rat masseter muscle hypertrophied by clenbuterol, a beta2 adrenergic agonist. Br J Pharmacol 2006; 147:412-21. [PMID: 16402040 PMCID: PMC1616986 DOI: 10.1038/sj.bjp.0706625] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
1. The regulatory mechanism for the hypertrophy of skeletal muscles induced by clenbuterol is unclear. The purpose of the present study was to determine the extent to which transforming growth factor betas (TGFbetas), fibroblast growth factors (FGFs), hepatocyte growth factor (HGF), and platelet-derived growth factors (PDGFs) are involved in the hypertrophy of rat masseter muscle induced by clenbuterol. 2. We measured the mRNA expression levels for TGFbetas, FGFs, HGF, and PDGFs in rat masseter muscle hypertrophied by oral administration of clenbuterol for 3 weeks and determined correlations between the weight of masseter muscle and mRNA expression levels by regression analysis. We determined immunolocalizations of TGFbetas and their receptors (TGFbetaRs). 3. The mRNA expression levels for TGFbeta1, 2, and 3, and for PDGF-B demonstrated clenbuterol-induced elevations and positive correlations with the weight of masseter muscle. In particular, TGFbeta1, 2, and 3 showed strong positive correlations (correlation coefficients >0.6). The mRNA expression levels for PDGF-A, FGF-1 and 2, and HGF showed no significant differences between the control and clenbuterol groups, and no significant correlations. TGFbeta1, 2, and 3 were principally localized in the connective tissues interspaced among myofibers, and TGFbetaRI and II were localized in the periphery and sarcoplasm of the myofibers. 4. These results suggest that paracrine actions of TGFbeta1, 2, and 3 via TGFbetaRI and II could be involved in the hypertrophy of rat masseter muscle induced by clenbuterol. This is the first study to document the involvement of TGFbetas in the hypertrophy of skeletal muscles induced by clenbuterol.
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Affiliation(s)
- Satonari Akutsu
- Katayanagi Advanced Research Laboratories, Tokyo University of Technology, Hachioji, Tokyo, Japan
| | - Akemi Shimada
- Department of Pharmacology, Tsurumi University School of Dental Medicine, 2-1-3 Tsurumi, Tsurumi-ku, Yokohama 230-8501, Japan
| | - Akira Yamane
- Department of Pharmacology, Tsurumi University School of Dental Medicine, 2-1-3 Tsurumi, Tsurumi-ku, Yokohama 230-8501, Japan
- Author for correspondence:
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Burkhoff D, Klotz S, Mancini DM. LVAD-Induced Reverse Remodeling: Basic and Clinical Implications for Myocardial Recovery. J Card Fail 2006; 12:227-39. [PMID: 16624689 DOI: 10.1016/j.cardfail.2005.10.012] [Citation(s) in RCA: 124] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2005] [Revised: 10/09/2005] [Accepted: 10/18/2005] [Indexed: 10/24/2022]
Abstract
BACKGROUND With improved technology, increasing clinical experience, and expanding indications for use, left ventricular assist devices (LVADs) are assuming a greater role in the care of patients with end-stage heart failure. Early in the course of LVAD use as a bridge to transplant, it became evident that some patients exhibit substantial recovery of ventricular function, which led to the concept of reverse remodeling. METHODS AND RESULTS Herein we summarize and integrate insights derived from a multitude of studies that have investigated how LVAD support influences ventricular structural, cellular, extracellular matrix, molecular, biochemical, and metabolic characteristics of the end-stage failing heart. The focus includes a review of the extent and sustainability of reverse remodeling, the important advances in understanding of the pathophysiology of heart failure derived from these studies and the implications of these findings for development of new therapeutic strategies. CONCLUSION In brief, studies of LVAD-heart interactions have led to the understanding that although we once considered the end-stage failing heart of patients near death to be irreversibly diseased, when given sufficient mechanical unloading and restoration of more normal neurohormonal milieu, a relatively large degree of myocardial recovery is possible. Comparison of effects on right and left ventricles have provided mechanistic insights by implicating hemodynamic unloading as primarily regulating certain aspects of reverse remodeling, neurohormonal factors as regulating other aspects, and joint regulation of still other aspects. As such these observations have driven a shift of thinking of chronic heart failure as a progressive irreversible disease process to a potentially treatable entity.
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Affiliation(s)
- Daniel Burkhoff
- J. Skirball Center for Cardiovascular Research, Cardiovascular Research Foundation, Orangeburg, NY 10962, USA
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47
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Burniston JG, Chester N, Clark WA, Tan LB, Goldspink DF. Dose-dependent apoptotic and necrotic myocyte death induced by the beta2-adrenergic receptor agonist, clenbuterol. Muscle Nerve 2006; 32:767-74. [PMID: 16007677 PMCID: PMC1831534 DOI: 10.1002/mus.20407] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
We have investigated the dose- and time-dependency of myocyte apoptosis and necrosis induced by the beta2-adrenergic receptor agonist, clenbuterol, with the aim of determining whether myocyte apoptosis and necrosis are two separate processes or a continuum of events. Male Wistar rats were administered subcutaneous injections of clenbuterol, and immunohistochemistry was used to detect myocyte-specific apoptosis and necrosis. Myocyte apoptosis peaked 4 h after, and necrosis 12 h after, clenbuterol administration. In the soleus, peak apoptosis (5.8 +/- 2.0%; P < 0.05) was induced by 10 mug and peak necrosis (7.4 +/- 1.7%; P < 0.05) by 5 mg x kg(-1) clenbuterol. Twelve hours after clenbuterol administration, 73% of damaged myocytes labeled as necrotic, 27% as apoptotic and necrotic, and 0% as purely apoptotic. Administrations of clenbuterol (10 microg x kg(-1)) at 48-h intervals induced cumulative myocyte death over 8 days. These data show that the phenotype of myocyte death is dependent on the magnitude of the insult and the time at which it is investigated. Only very low doses induced apoptosis alone; in most cases apoptotic myocytes lysed and became necrotic and the magnitude of necrosis was greater than that of apoptosis. Thus, it is important to investigate both apoptotic and necrotic myocyte death, contrary to the current trend of only investigating apoptotic cell death.
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Affiliation(s)
- Jatin G Burniston
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Webster Street, Liverpool L3 2ET, UK.
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48
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Tsuneyoshi H, Oriyanhan W, Kanemitsu H, Shiina R, Nishina T, Matsuoka S, Ikeda T, Komeda M. Does the beta2-agonist clenbuterol help to maintain myocardial potential to recover during mechanical unloading? Circulation 2006; 112:I51-6. [PMID: 16159865 DOI: 10.1161/circulationaha.104.525097] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Chronic mechanical unloading induces left ventricular (LV) atrophy, which may impair functional recovery during support with an LV-assist device. Clenbuterol, a beta2-adrenergic receptor (AR) agonist, is known to induce myocardial hypertrophy and might prevent LV atrophy during LV unloading. Furthermore, beta2-AR stimulation is reported to improve Ca2+ handling and contribute to antiapoptosis. However, there is little information on the effects of clenbuterol during LV unloading. METHODS AND RESULTS We investigated LV atrophy and function after LV unloading produced by heterotopic heart transplantation in isogenic rats. After transplantation, rats were randomized to 1 of 2 groups (n=10 each). The clenbuterol group received 2 mg.kg(-1).d(-1) of the drug for 2 weeks; the control group received normal saline. The weight of unloaded control hearts was 48% less than that of host hearts after 2 weeks of unloading. Clenbuterol significantly increased the weight of the host hearts but did not prevent unloading-induced LV atrophy. Papillary muscles were isolated and stimulated, and there was no difference in developed tension between the 2 groups. However, the inotropic response to the beta-AR agonist isoproterenol significantly improved in the clenbuterol group. The mRNA expression of myocardial sarco(endo)plasmic reticulum Ca2+-ATPase 2a (SERCA2a) and fetal gene shift (myosin heavy chain [MHC] mRNA isozyme) was also significantly improved by clenbuterol treatment. There was no difference in beta1-AR mRNA expression between the 2 groups. In contrast, beta2-AR mRNA was significantly decreased in the clenbuterol-treated, unloaded heart. This indicates that clenbuterol may downregulate beta2-ARs. In the evaluation of apoptosis, mRNA expression of caspase-3, which is the central pathway for apoptosis, tended to be better in the clenbuterol group. CONCLUSIONS During complete LV unloading, clenbuterol did not prevent myocardial atrophy but improved gene expression (SERCA2a, beta-MHC) and beta-adrenergic responsiveness and potentially prevented myocardial apoptosis. However, chronic administration of clenbuterol may be associated with downregulation of beta2-ARs.
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MESH Headings
- Adrenergic beta-Agonists/pharmacology
- Adrenergic beta-Agonists/therapeutic use
- Animals
- Atrophy
- Calcium-Transporting ATPases/biosynthesis
- Calcium-Transporting ATPases/genetics
- Caspase 3
- Caspases/biosynthesis
- Caspases/genetics
- Clenbuterol/pharmacology
- Clenbuterol/therapeutic use
- Down-Regulation/drug effects
- Drug Evaluation, Preclinical
- Enzyme Induction/drug effects
- Gene Expression Regulation/drug effects
- Heart/drug effects
- Heart Transplantation
- Heart Ventricles/drug effects
- Heart Ventricles/pathology
- Heart Ventricles/physiopathology
- Isoproterenol/pharmacology
- Male
- Myocardial Contraction/drug effects
- Myocardium/pathology
- Myosin Heavy Chains/biosynthesis
- Myosin Heavy Chains/genetics
- Organ Size
- Papillary Muscles/drug effects
- Papillary Muscles/physiopathology
- Protein Isoforms/biosynthesis
- Protein Isoforms/genetics
- RNA, Messenger/biosynthesis
- RNA, Messenger/genetics
- Random Allocation
- Rats
- Rats, Inbred Lew
- Receptors, Adrenergic, beta-1/biosynthesis
- Receptors, Adrenergic, beta-1/genetics
- Receptors, Adrenergic, beta-2/biosynthesis
- Receptors, Adrenergic, beta-2/drug effects
- Receptors, Adrenergic, beta-2/genetics
- Sarcoplasmic Reticulum Calcium-Transporting ATPases
- Stress, Mechanical
- Transplantation, Heterotopic
- Transplantation, Isogeneic
- Ventricular Function, Left/drug effects
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Affiliation(s)
- Hiroshi Tsuneyoshi
- Department of Cardiovascular Surgery, Graduate School of Medicine, Kyoto University, Kyoto, 606-8507, Japan
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49
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Xydas S, Kherani AR, Chang JS, Klotz S, Hay I, Mutrie CJ, Moss GW, Gu A, Schulman AR, Gao D, Hu D, Wu EX, Wei C, Oz MC, Wang J. β2-Adrenergic Stimulation Attenuates Left Ventricular Remodeling, Decreases Apoptosis, and Improves Calcium Homeostasis in a Rodent Model of Ischemic Cardiomyopathy. J Pharmacol Exp Ther 2006; 317:553-61. [PMID: 16421285 DOI: 10.1124/jpet.105.099432] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The benefit of the beta(2)-adrenergic agonist, clenbuterol, in left ventricular assist device patients with dilated cardiomyopathy has been reported, but its effect on ischemic heart failure (HF) is unknown. We investigated whether clenbuterol improves left ventricular remodeling, myocardial apoptosis and has synergy with a beta(1) antagonist, metoprolol, in a model of ischemic HF. Rats were randomized to: 1) HF only; 2) HF + clenbuterol; 3) HF + metoprolol; 4) HF + clenbuterol + metoprolol; and 5) rats with sham surgery. HF was induced by left anterior descending artery (LAD) artery ligation and confirmed by decreased left ventricular fractional shortening, decreased maximum left ventricular dP/dt (dP/dt(max)), and elevated left ventricular end-diastolic pressure (LVEDP) compared with sham rats (p < 0.01). After 9 weeks of oral therapy, echocardiographic, hemodynamic, and ex vivo end-diastolic pressure-volume relationship (EDPVR) measurements were obtained. Immunohistochemistry was performed for myocardial apoptosis and DNA damage markers. Levels of calcium-handling proteins were assessed by Western blot analysis. Clenbuterol-treated HF rats had increased weight gain and heart weights versus HF rats (p < 0.05). EDPVR curves revealed a leftward shift in clenbuterol rats versus metoprolol and HF rats (p < 0.05). The metoprolol-treated group had a lower LVEDP and higher dP/dt(max) versus the HF group (p < 0.05). Clenbuterol and metoprolol groups had decreased myocardial apoptosis and DNA damage markers and increased DNA repair markers versus HF rats (all p < 0.01). Protein levels of the ryanodine receptor and sarcoplasmic reticulum calcium-ATPase were improved in clenbuterol-, metoprolol-, and clenbuterol+metoprolol-treated groups versus HF rats. However, as a combination therapy, there were no synergistic effects of clenbuterol+metoprolol treatment. We conclude that clenbuterol ameliorates EDPVR, apoptosis, and calcium homeostasis but does not have synergy with metoprolol in our model of ischemic HF.
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Affiliation(s)
- Steve Xydas
- Department of Surgery, Columbia University College of Physicians and Surgeons, New York, New York, USA
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50
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Gregorevic P, Ryall JG, Plant DR, Sillence MN, Lynch GS. Chronic β-agonist administration affects cardiac function of adult but not old rats, independent of β-adrenoceptor density. Am J Physiol Heart Circ Physiol 2005; 289:H344-9. [PMID: 15734875 DOI: 10.1152/ajpheart.01254.2004] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Although β-adrenoceptor agonists have clinical merit for attenuating the age-related loss of skeletal muscle mass and strength (sarcopenia), potential cardiac-related side effects may limit their clinical application. The aim of this study was to determine whether chronic β-agonist administration impairs cardiac function in adult or aged rats. Adult (16 mo) and aged (28 mo) Fischer 344 rats were treated with fenoterol (1.4 mg·kg−1·day−1 ip) or vehicle for 4 wk. Heart function was assessed in vitro before analyses of cardiac structure and β-adrenoceptor density. Heart mass increased 17% and 25% in fenoterol-treated adult and aged rats, respectively. The increased heart mass in aged, but not adult, rats was associated with a relative increase in collagen content. Cardiac hypertrophy in adult rats was associated with an increase in left ventricular developed pressure, a marked reduction in cardiac output, and a reduction in coronary flow per unit heart mass. In contrast, negligible differences in ventricular function were observed in fenoterol-treated aged rats. The differential effect on contractile function was not associated with age-related differences in β-adrenoceptor density but, rather, an age-related increase in downregulation after treatment. Our results show that chronic β-agonist treatment impairs cardiac function to a greater extent in adult than in aged rats. These results provide important information regarding the potential effects of chronic β-agonist use on cardiac function and the future development of safe and effective treatments for sarcopenia.
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Affiliation(s)
- Paul Gregorevic
- Dept. of Physiology, The Univ. of Melbourne, Victoria 3010, Australia
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