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Liu X, Li B, Wang S, Zhang E, Schultz M, Touma M, Monteiro Da Rocha A, Evans SM, Eichmann A, Herron T, Chen R, Xiong D, Jaworski A, Weiss S, Si MS. Stromal Cell-SLIT3/Cardiomyocyte-ROBO1 Axis Regulates Pressure Overload-Induced Cardiac Hypertrophy. Circ Res 2024; 134:913-930. [PMID: 38414132 PMCID: PMC10977056 DOI: 10.1161/circresaha.122.321292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 02/08/2024] [Accepted: 02/12/2024] [Indexed: 02/29/2024]
Abstract
BACKGROUND Recently shown to regulate cardiac development, the secreted axon guidance molecule SLIT3 maintains its expression in the postnatal heart. Despite its known expression in the cardiovascular system after birth, SLIT3's relevance to cardiovascular function in the postnatal state remains unknown. As such, the objectives of this study were to determine the postnatal myocardial sources of SLIT3 and to evaluate its functional role in regulating the cardiac response to pressure overload stress. METHODS We performed in vitro studies on cardiomyocytes and myocardial tissue samples from patients and performed in vivo investigation with SLIT3 and ROBO1 (roundabout homolog 1) mutant mice undergoing transverse aortic constriction to establish the role of SLIT3-ROBO1 in adverse cardiac remodeling. RESULTS We first found that SLIT3 transcription was increased in myocardial tissue obtained from patients with congenital heart defects that caused ventricular pressure overload. Immunostaining of hearts from WT (wild-type) and reporter mice revealed that SLIT3 is secreted by cardiac stromal cells, namely fibroblasts and vascular mural cells, within the heart. Conditioned media from cardiac fibroblasts and vascular mural cells both stimulated cardiomyocyte hypertrophy in vitro, an effect that was partially inhibited by an anti-SLIT3 antibody. Also, the N-terminal, but not the C-terminal, fragment of SLIT3 and the forced overexpression of SLIT3 stimulated cardiomyocyte hypertrophy and the transcription of hypertrophy-related genes. We next determined that ROBO1 was the most highly expressed roundabout receptor in cardiomyocytes and that ROBO1 mediated SLIT3's hypertrophic effects in vitro. In vivo, Tcf21+ fibroblast and Tbx18+ vascular mural cell-specific knockout of SLIT3 in mice resulted in decreased left ventricular hypertrophy and cardiac fibrosis after transverse aortic constriction. Furthermore, α-MHC+ cardiomyocyte-specific deletion of ROBO1 also preserved left ventricular function and abrogated hypertrophy, but not fibrosis, after transverse aortic constriction. CONCLUSIONS Collectively, these results indicate a novel role for the SLIT3-ROBO1-signaling axis in regulating postnatal cardiomyocyte hypertrophy induced by pressure overload.
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Affiliation(s)
- Xiaoxiao Liu
- Department of Cardiac Surgery (X.L., B.L., S.W., D.X., M.-S.S.), Michigan Medicine, Ann Arbor
- Department of Cardiology, Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Shanghai Medical College of Fudan University, China (X.L., R.C.)
| | - Baolei Li
- Department of Cardiac Surgery (X.L., B.L., S.W., D.X., M.-S.S.), Michigan Medicine, Ann Arbor
- Department of Pediatric Cardiology, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, China (B.L.)
| | - Shuyun Wang
- Department of Cardiac Surgery (X.L., B.L., S.W., D.X., M.-S.S.), Michigan Medicine, Ann Arbor
| | - Erge Zhang
- Division of Cardiac Surgery, Department of Surgery (E.Z., M.S., M.-S.S.), David Geffen School of Medicine University of California, Los Angeles
| | - Megan Schultz
- Division of Cardiac Surgery, Department of Surgery (E.Z., M.S., M.-S.S.), David Geffen School of Medicine University of California, Los Angeles
| | - Marlin Touma
- Department of Pediatrics (M.T.), David Geffen School of Medicine University of California, Los Angeles
| | - Andre Monteiro Da Rocha
- Division of Cardiovascular Medicine, Department of Internal Medicine (A.M.D.R., T.H.), Michigan Medicine, Ann Arbor
| | - Sylvia M. Evans
- Skaggs School of Pharmacy and Pharmaceutical Sciences (S.M.E.), University of California, San Diego, La Jolla
- Department of Medicine, School of Medicine (S.M.E.), University of California, San Diego, La Jolla
| | - Anne Eichmann
- Department of Internal Medicine, Cardiovascular Research Center, Yale University School of Medicine, New Haven, CT (A.E.)
- INSERM, Paris Cardiovascular Research Center (PARCC), Université de Paris, France (A.E.)
| | - Todd Herron
- Division of Cardiovascular Medicine, Department of Internal Medicine (A.M.D.R., T.H.), Michigan Medicine, Ann Arbor
| | - Ruizhen Chen
- Department of Cardiology, Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Shanghai Medical College of Fudan University, China (X.L., R.C.)
| | - Dingding Xiong
- Department of Cardiac Surgery (X.L., B.L., S.W., D.X., M.-S.S.), Michigan Medicine, Ann Arbor
| | - Alexander Jaworski
- Division of Biology and Medicine, Department of Neuroscience, Brown University, Providence, RI (A.J.)
| | - Stephen Weiss
- Life Sciences Institute, University of Michigan, Ann Arbor (S.W.)
| | - Ming-Sing Si
- Department of Cardiac Surgery (X.L., B.L., S.W., D.X., M.-S.S.), Michigan Medicine, Ann Arbor
- Division of Cardiac Surgery, Department of Surgery (E.Z., M.S., M.-S.S.), David Geffen School of Medicine University of California, Los Angeles
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Gintant G, Burridge P, Gepstein L, Harding S, Herron T, Hong C, Jalife J, Wu JC. Use of Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes in Preclinical Cancer Drug Cardiotoxicity Testing: A Scientific Statement From the American Heart Association. Circ Res 2019; 125:e75-e92. [PMID: 31533542 DOI: 10.1161/res.0000000000000291] [Citation(s) in RCA: 86] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
It is now well recognized that many lifesaving oncology drugs may adversely affect the heart and cardiovascular system, including causing irreversible cardiac injury that can result in reduced quality of life. These effects, which may manifest in the short term or long term, are mechanistically not well understood. Research is hampered by the reliance on whole-animal models of cardiotoxicity that may fail to reflect the fundamental biology or cardiotoxic responses of the human myocardium. The emergence of human induced pluripotent stem cell-derived cardiomyocytes as an in vitro research tool holds great promise for understanding drug-induced cardiotoxicity of oncological drugs that may manifest as contractile and electrophysiological dysfunction, as well as structural abnormalities, making it possible to deliver novel drugs free from cardiac liabilities and guide personalized therapy. This article briefly reviews the challenges of cardio-oncology, the strengths and limitations of using human induced pluripotent stem cell-derived cardiomyocytes to represent clinical findings in the nonclinical research space, and future directions for their further use.
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Anumonwo JMB, Herron T. Fatty Infiltration of the Myocardium and Arrhythmogenesis: Potential Cellular and Molecular Mechanisms. Front Physiol 2018; 9:2. [PMID: 29403390 PMCID: PMC5786512 DOI: 10.3389/fphys.2018.00002] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Accepted: 01/03/2018] [Indexed: 11/13/2022] Open
Abstract
Anatomical evidence in several species shows highly heterogeneous fat distribution in the atrial and ventricular myocardium. Atrial appendages have fat deposits, and more so on the posterior left atrium. Although such fat distributions are considered normal, fatty infiltration is regarded arrhythmogenic, and various cardiac pathophysiological conditions show excess myocardial fat deposits, especially in the epicardium. Hypotheses have been presented for the physiological and pathophysiological roles of epicardial fat, however this issue is poorly understood. Therefore, this mini-review will focus on epicardial fat distribution and the (patho)-physiological implications of this distribution. Potential molecular mechanisms that may drive structural and electrical myocardial remodeling attendant to fatty infiltration of the heart are also reviewed.
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Affiliation(s)
- Justus M B Anumonwo
- Department of Internal Medicine (Cardiovascular Medicine), Center for Arrythmia Research, University of Michigan, Ann Arbor, MI, United States
| | - Todd Herron
- Department of Internal Medicine (Cardiovascular Medicine), Center for Arrythmia Research, University of Michigan, Ann Arbor, MI, United States
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Baker LH, Ploutz-Snyder L, Jalife J, Palmieri-Smith R, Herron T, Murthy VL, Weinberg RL, Reinke D. Abstract B37: Evaluation of cardiovascular and musculoskeletal health in sarcoma survivors. Clin Cancer Res 2018. [DOI: 10.1158/1557-3265.sarcomas17-b37] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: Children, teenagers, and young adult survivors of bone sarcoma have a 39-fold risk of developing a severe, life-threatening, or fatal chronic medical condition compared to their siblings. Heart disease is the most common and serious chronic illness observed in sarcoma survivors treated with doxorubicin (DOX). The commonest heart disease in these survivors is coronary artery disease (CAD). Long-term cardiotoxicity is a significant problem of DOX but the underlying pathogenesis and pathophysiology remains incompletely understood. Until recently, it was assumed that the DOX effect was limited to cardiomyopathy, but we now posit that DOX is also associated with CAD as well as with arrhythmias. Though commonly used, ejection fraction is not predictive of any of these acquired heart diseases. Better and earlier diagnoses are needed. We established a Sarcoma Survivorship Program to include patients at high risk of chronic illness who are at least two years free of disease after completion of treatment.
Methods: Every 6 months, patients electronically complete NIH's PROMIS (Patient-Reported Outcomes Measurement Information System) questionnaires (on Anxiety, Depression, Mobility, Pain Interference, Sleep Disturbance, and Physical Function). Detailed family history is documented. Chemotherapy doses are abstracted from original medical records. Data collected include blood pressure, lipid profile, high-sensitivity C-reactive protein (hs-CRP), basic metabolic panel, chemistries, renal and pulmonary function, and expert echocardiography. All patients signed an IRB approved informed consent.
Results: All patients had normal left ventricular ejection fractions (median= 60%), yet 8 (N=24) patients had an elevated high-sensitivity C-reactive protein suggesting increased risk of early CAD. 10 patients had untreated hypertension. More than half of our patients have a BMI >25 and self-declare that they do not exercise. Our high rate of family history of heart disease (58%) in first-degree relatives raises the issue of genetic predisposition both to heart disease and sarcoma. We compared standardized cardiac risk assessments with mediastinal calcification and epicardial fat on serial chest CT scans. A 39-year-old man had a coronary calcium score >400 Agatston units and scattered calcifications were remarkably found in 4 additional patients under the age of 40.
Conclusions: This survivorship phase of oncologic care represents a unique opportunity to improve the health and quality of life for sarcoma survivors as well as a new focus for translational research to understand mechanisms driving premature aging and chronic heart disease. We assess cardiomyocyte function (cell viability, organization, fibrosis, electrical coupling, and contractility) for survivors and matched sibling controls with cells from skin biopsy using 3D bioengineering techniques to culture and mature the phenotype from human stem cells. Altering lifestyle through weight management and increased physical aerobic and anaerobic exercise is the best approach to reducing coronary artery disease. Our team includes expert exercise physiologists to better understand mechanisms limiting exercise in patients with amputation or limb salvage surgeries and in turn develop individualized appropriate exercise regimens utilizing research methodologies used by NASA to improve the performance of our astronauts in space. These lab technologies are being prospectively applied into a patient population of sarcoma survivors to understand the extent and cause of physical limitation of amputation vs. limb-salvage surgery as well as to understand the mechanisms of acquired cardiac disease. We must improve our knowledge of the long-term cardiac risk associated with surviving a sarcoma to effectively counsel survivors and offer existing effective intervention strategies to prevent or minimize the impact of adverse late effects.
Citation Format: Laurence H. Baker, Lori Ploutz-Snyder, Jose Jalife, Rianna Palmieri-Smith, Todd Herron, Venkatesh L. Murthy, Richard L. Weinberg, Denise Reinke. Evaluation of cardiovascular and musculoskeletal health in sarcoma survivors [abstract]. In: Proceedings of the AACR Conference on Advances in Sarcomas: From Basic Science to Clinical Translation; May 16-19, 2017; Philadelphia, PA. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(2_Suppl):Abstract nr B37.
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Affiliation(s)
- Laurence H. Baker
- 1University of Michigan Sarcoma Survivorship Program, Ann Arbor, MI,
| | | | - Jose Jalife
- 3University of Michigan Department of Internal Medicine, Division of Cardiovascular Medicine, Ann Arbor, MI
| | | | - Todd Herron
- 3University of Michigan Department of Internal Medicine, Division of Cardiovascular Medicine, Ann Arbor, MI
| | - Venkatesh L. Murthy
- 3University of Michigan Department of Internal Medicine, Division of Cardiovascular Medicine, Ann Arbor, MI
| | - Richard L. Weinberg
- 3University of Michigan Department of Internal Medicine, Division of Cardiovascular Medicine, Ann Arbor, MI
| | - Denise Reinke
- 1University of Michigan Sarcoma Survivorship Program, Ann Arbor, MI,
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Biton Y, Rabinovitch A, Braunstein D, Aviram I, Campbell K, Mironov S, Herron T, Jalife J, Berenfeld O. Causality analysis of leading singular value decomposition modes identifies rotor as the dominant driving normal mode in fibrillation. Chaos 2018; 28:013128. [PMID: 29390625 PMCID: PMC5786449 DOI: 10.1063/1.5021261] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Accepted: 12/28/2017] [Indexed: 06/07/2023]
Abstract
Cardiac fibrillation is a major clinical and societal burden. Rotors may drive fibrillation in many cases, but their role and patterns are often masked by complex propagation. We used Singular Value Decomposition (SVD), which ranks patterns of activation hierarchically, together with Wiener-Granger causality analysis (WGCA), which analyses direction of information among observations, to investigate the role of rotors in cardiac fibrillation. We hypothesized that combining SVD analysis with WGCA should reveal whether rotor activity is the dominant driving force of fibrillation even in cases of high complexity. Optical mapping experiments were conducted in neonatal rat cardiomyocyte monolayers (diameter, 35 mm), which were genetically modified to overexpress the delayed rectifier K+ channel IKr only in one half of the monolayer. Such monolayers have been shown previously to sustain fast rotors confined to the IKr overexpressing half and driving fibrillatory-like activity in the other half. SVD analysis of the optical mapping movies revealed a hierarchical pattern in which the primary modes corresponded to rotor activity in the IKr overexpressing region and the secondary modes corresponded to fibrillatory activity elsewhere. We then applied WGCA to evaluate the directionality of influence between modes in the entire monolayer using clear and noisy movies of activity. We demonstrated that the rotor modes influence the secondary fibrillatory modes, but influence was detected also in the opposite direction. To more specifically delineate the role of the rotor in fibrillation, we decomposed separately the respective SVD modes of the rotor and fibrillatory domains. In this case, WGCA yielded more information from the rotor to the fibrillatory domains than in the opposite direction. In conclusion, SVD analysis reveals that rotors can be the dominant modes of an experimental model of fibrillation. Wiener-Granger causality on modes of the rotor domains confirms their preferential driving influence on fibrillatory modes.
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Affiliation(s)
- Yaacov Biton
- Physics Department, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
| | - Avinoam Rabinovitch
- Physics Department, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
| | - Doron Braunstein
- Physics Department, Sami Shamoon College of Engineering, Beer-Sheva 84100, Israel
| | - Ira Aviram
- Physics Department, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
| | - Katherine Campbell
- Center for Arrhythmia Research, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Sergey Mironov
- Center for Arrhythmia Research, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Todd Herron
- Center for Arrhythmia Research, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - José Jalife
- Center for Arrhythmia Research, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Omer Berenfeld
- Center for Arrhythmia Research, University of Michigan, Ann Arbor, Michigan 48109, USA
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6
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Baker LH, Murthy VL, Weinberg RL, Jalife J, Herron T. Evaluation of cardiovascular health in sarcoma survivors. J Clin Oncol 2017. [DOI: 10.1200/jco.2017.35.15_suppl.e21579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
e21579 Background: Heart disease is the most common and serious chronic illness observed in sarcoma survivors treated with doxorubicin. Now the commonest heart disease in theses survivors is coronary artery disease (CAD). We established a Sarcoma Survivorship Program to include patients at high risk of chronic illness including exposure to doxorubicin who are at least 2 years free of disease post treatment. Methods: Every 6 months patients electronically complete NIH’s PROMIS (Patient-Reported Outcomes Measurement Information System) questionnaires (on Anxiety, Depression, Mobility, Pain Interference, Sleep Disturbance, and Physical Function). Detailed family history is documented. Chemotherapy doses are abstracted from original medical records. Data collected includes: blood pressure, lipid profile, high-sensitivity C-reactive protein (hs-CRP), basic metabolic panel, chemistries, renal and pulmonary function, expert echocardiography. All patients signed an IRB approved informed consent. Results: All patients had normal left ventricular ejection fractions (median = 60%) yet 8 (N = 24) patients had an elevated hs-CRP suggesting increased risk of early CAD. 10 patients had untreated hypertension. More than half of our patients have a BMI > 25 and self-declare that they do not exercise. Our high rate of family history of heart disease (58%) raises the issue of genetic predisposition both to heart disease and sarcoma. We compared standardized cardiac risk assessments with mediastinal calcification and epicardial fat on serial chest CT scans. A 39 y.o. man had a coronary calcium score > 400 Agatston units and scattered calcifications were found in 4 additional patients under the age of 40. Conclusions: This survivorship phase of oncologic care represents a unique opportunity to improve the health and quality of life for sarcoma survivors as well as a new focus for translational research to understand mechanisms driving premature aging and chronic heart disease. We assess cardiomyocyte function (cell viability, organization, fibrosis, electrical coupling and contractility) for survivors and matched sibling controls with cells from skin biopsy using 3D bioengineering techniques to culture and mature the phenotype from human stem cells.
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7
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Klos M, Mundada L, Banerjee I, Morgenstern S, Myers S, Leone M, Kleid M, Herron T, Devaney E. Altered myocyte contractility and calcium homeostasis in alpha-myosin heavy chain point mutations linked to familial dilated cardiomyopathy. Arch Biochem Biophys 2017; 615:53-60. [PMID: 28088328 DOI: 10.1016/j.abb.2016.12.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Revised: 12/06/2016] [Accepted: 12/17/2016] [Indexed: 01/19/2023]
Abstract
Mutations in the human cardiac motor protein beta-myosin heavy chain (βMHC) have been long recognized as a cause of familial hypertrophic cardiomyopathy. Recently, mutations (P830L and A1004S) in the less abundant but faster isoform alpha-myosin heavy chain (αMHC) have been linked to dilated cardiomyopathy (DCM). In this study, we sought to determine the cellular contractile phenotype associated with these point mutations. Ventricular myocytes were isolated from 2 month male Sprague Dawley rats. Cells were cultured in M199 media and infected with recombinant adenovirus containing the P830L or the A1004S mutant human αMHC at a MOI of 500 for 18 h. Uninfected cells (UI), human βMHC (MOI 500, 18 h), and human αMHC (MOI 500, 18 h) were used as controls. Cells were loaded with fura-2 (1 μM, 15 min) after 48 h. Sarcomere shortening and calcium transients were recorded in CO2 buffered M199 media (36°±1 C) with and without 10 nM isoproterenol (Iso). The A1004S mutation resulted in decreased peak sarcomere shortening while P830L demonstrated near normal shortening kinetics at baseline. In the presence of Iso, the A1004S sarcomere shortening was identical to the βMHC shortening while the P830L was identical to the αMHC control. All experimental groups had identical calcium transients. Despite a shared association with DCM, the P830L and A1004S αMHC mutations alter myocyte contractility in completely different ways while at the same preserving peak intracellular calcium.
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Affiliation(s)
- Matthew Klos
- Department of Pediatric Cardiac Surgery, UH Hospitals Cleveland, Cleveland, OH 44106, USA
| | - Lakshmi Mundada
- Department of Internal Medicine, Cardiovascular Medicine, Center for Arrhythmia Research, University of Michigan, Ann Arbor, MI 48108, USA
| | - Indroneal Banerjee
- Department of Medicine, University of California, San Diego, CA 92103, USA
| | - Sherry Morgenstern
- Department of Pediatric Cardiac Surgery, UH Hospitals Cleveland, Cleveland, OH 44106, USA
| | - Stephanie Myers
- Department of Medicine, University of California, San Diego, CA 92103, USA
| | - Michael Leone
- Department of Medicine, University of California, San Diego, CA 92103, USA
| | - Mark Kleid
- Department of Medicine, University of California, San Diego, CA 92103, USA
| | - Todd Herron
- Department of Internal Medicine, Cardiovascular Medicine, Center for Arrhythmia Research, University of Michigan, Ann Arbor, MI 48108, USA
| | - Eric Devaney
- Department of Pediatric Cardiac Surgery, UH Hospitals Cleveland, Cleveland, OH 44106, USA.
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Avula UMR, Yoon HK, Lee CH, Kaur K, Ramirez RJ, Takemoto Y, Ennis SR, Morady F, Herron T, Berenfeld O, Kopelman R, Kalifa J. Cell-selective arrhythmia ablation for photomodulation of heart rhythm. Sci Transl Med 2016; 7:311ra172. [PMID: 26511509 DOI: 10.1126/scitranslmed.aab3665] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Heart disease, a leading cause of death in the developed world, is overwhelmingly correlated with arrhythmias, where heart muscle cells, myocytes, beat abnormally. Cardiac arrhythmias are usually managed by electric shock intervention, antiarrhythmic drugs, surgery, and/or catheter ablation. Despite recent improvements in techniques, ablation procedures are still limited by the risk of complications from unwanted cellular damage, caused by the nonspecific delivery of ablative energy to all heart cell types. We describe an engineered nanoparticle containing a cardiac-targeting peptide (CTP) and a photosensitizer, chlorin e6 (Ce6), for specific delivery to myocytes. Specificity was confirmed in vitro using adult rat heart cell and human stem cell-derived cardiomyocyte and fibroblast cocultures. In vivo, the CTP-Ce6 nanoparticles were injected intravenously into rats and, upon laser illumination of the heart, induced localized, myocyte-specific ablation with 85% efficiency, restoring sinus rhythm without collateral damage to other cell types in the heart, such as fibroblasts. In both sheep and rat hearts ex vivo, upon perfusion of CTP-Ce6 particles, laser illumination led to the formation of a complete electrical block at the ablated region and restored the physiological rhythm of the heart. This nano-based, cell-targeted approach could improve ablative technologies for patients with arrhythmias by reducing currently encountered complications.
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Affiliation(s)
- Uma Mahesh R Avula
- Division of Cardiovascular Medicine, Department of Internal Medicine, Center for Arrhythmia Research, University of Michigan, Ann Arbor, MI 48109, USA
| | - Hyung Ki Yoon
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, USA
| | - Chang H Lee
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, USA
| | - Kuljeet Kaur
- Division of Cardiovascular Medicine, Department of Internal Medicine, Center for Arrhythmia Research, University of Michigan, Ann Arbor, MI 48109, USA
| | - Rafael J Ramirez
- Division of Cardiovascular Medicine, Department of Internal Medicine, Center for Arrhythmia Research, University of Michigan, Ann Arbor, MI 48109, USA
| | - Yoshio Takemoto
- Division of Cardiovascular Medicine, Department of Internal Medicine, Center for Arrhythmia Research, University of Michigan, Ann Arbor, MI 48109, USA
| | - Steven R Ennis
- Division of Cardiovascular Medicine, Department of Internal Medicine, Center for Arrhythmia Research, University of Michigan, Ann Arbor, MI 48109, USA
| | - Fred Morady
- Division of Cardiovascular Medicine, Department of Internal Medicine, Center for Arrhythmia Research, University of Michigan, Ann Arbor, MI 48109, USA
| | - Todd Herron
- Division of Cardiovascular Medicine, Department of Internal Medicine, Center for Arrhythmia Research, University of Michigan, Ann Arbor, MI 48109, USA
| | - Omer Berenfeld
- Division of Cardiovascular Medicine, Department of Internal Medicine, Center for Arrhythmia Research, University of Michigan, Ann Arbor, MI 48109, USA
| | - Raoul Kopelman
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, USA.
| | - Jérôme Kalifa
- Division of Cardiovascular Medicine, Department of Internal Medicine, Center for Arrhythmia Research, University of Michigan, Ann Arbor, MI 48109, USA.
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Gaitas A, Malhotra R, Li T, Herron T, Jalife J. A device for rapid and quantitative measurement of cardiac myocyte contractility. Rev Sci Instrum 2015; 86:034302. [PMID: 25832250 PMCID: PMC4376763 DOI: 10.1063/1.4915500] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2015] [Accepted: 03/09/2015] [Indexed: 05/27/2023]
Abstract
Cardiac contractility is the hallmark of cardiac function and is a predictor of healthy or diseased cardiac muscle. Despite advancements over the last two decades, the techniques and tools available to cardiovascular scientists are limited in their utility to accurately and reliably measure the amplitude and frequency of cardiomyocyte contractions. Isometric force measurements in the past have entailed cumbersome attachment of isolated and permeabilized cardiomyocytes to a force transducer followed by measurements of sarcomere lengths under conditions of submaximal and maximal Ca(2+) activation. These techniques have the inherent disadvantages of being labor intensive and costly. We have engineered a micro-machined cantilever sensor with an embedded deflection-sensing element that, in preliminary experiments, has demonstrated to reliably measure cardiac cell contractions in real-time. Here, we describe this new bioengineering tool with applicability in the cardiovascular research field to effectively and reliably measure cardiac cell contractility in a quantitative manner. We measured contractility in both primary neonatal rat heart cardiomyocyte monolayers that demonstrated a beat frequency of 3 Hz as well as human embryonic stem cell-derived cardiomyocytes with a contractile frequency of about 1 Hz. We also employed the β-adrenergic agonist isoproterenol (100 nmol l(-1)) and observed that our cantilever demonstrated high sensitivity in detecting subtle changes in both chronotropic and inotropic responses of monolayers. This report describes the utility of our micro-device in both basic cardiovascular research as well as in small molecule drug discovery to monitor cardiac cell contractions.
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Affiliation(s)
- Angelo Gaitas
- Kytaro, Inc., 11200 SW 8th Street, MARC 430, Miami, Florida 33199, USA
| | - Ricky Malhotra
- Kytaro, Inc., 11200 SW 8th Street, MARC 430, Miami, Florida 33199, USA
| | - Tao Li
- Electrical Engineering and Computer Science, University of Michigan, 1301 Beal Ave., Ann Arbor, Michigan 48109, USA
| | - Todd Herron
- Center for Arrhythmia Research, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - José Jalife
- Center for Arrhythmia Research, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan 48109, USA
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Rocha A, Herron T, Klos M, Day S, Jalife J, Smith G. Human embryonic stem cells from a preimplantation genetic diagnosis-tested and affected embryo with mutation in myosin binding protein C3 phenocopies hypertropic cardiomyopathy. Fertil Steril 2013. [DOI: 10.1016/j.fertnstert.2013.07.1803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Campbell K, Calvo CJ, Mironov S, Herron T, Berenfeld O, Jalife J. Spatial gradients in action potential duration created by regional magnetofection of hERG are a substrate for wavebreak and turbulent propagation in cardiomyocyte monolayers. J Physiol 2012; 590:6363-79. [PMID: 23090949 DOI: 10.1113/jphysiol.2012.238758] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Spatial dispersion of action potential duration (APD) is a substrate for the maintenance of cardiac fibrillation, but the mechanisms are poorly understood. We investigated the role played by spatial APD dispersion in fibrillatory dynamics. We used an in vitro model in which spatial gradients in the expression of ether-à-go-go-related (hERG) protein, and thus rapid delayed rectifying K(+) current (I(Kr)) density, served to generate APD dispersion, high-frequency rotor formation, wavebreak and fibrillatory conduction. A unique adenovirus-mediated magnetofection technique generated well-controlled gradients in hERG and green fluorescent protein (GFP) expression in neonatal rat ventricular myocyte monolayers. Computer simulations using a realistic neonatal rat ventricular myocyte monolayer model provided crucial insight into the underlying mechanisms. Regional hERG overexpression shortened APD and increased rotor incidence in the hERG overexpressing region. An APD profile at 75 percent repolarization with a 16.6 ± 0.72 ms gradient followed the spatial profile of hERG-GFP expression; conduction velocity was not altered. Rotors in the infected region whose maximal dominant frequency was 12.9 Hz resulted in wavebreak at the interface (border zone) between infected and non-infected regions; dominant frequency distribution was uniform when the maximal dominant frequency was <12.9 Hz or the rotors resided in the uninfected region. Regularity at the border zone was lowest when rotors resided in the infected region. In simulations, a fivefold regional increase in I(Kr) abbreviated the APD and hyperpolarized the resting potential. However, the steep APD gradient at the border zone proved to be the primary mechanism of wavebreak and fibrillatory conduction. This study provides insight at the molecular level into the mechanisms by which spatial APD dispersion contributes to wavebreak, rotor stabilization and fibrillatory conduction.
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Affiliation(s)
- Katherine Campbell
- Center for Arrhythmia Research, Department of InternalMedicine, University of Michigan, Ann Arbor, MI 48108, USA
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Cate A, Herron T, Kang X, Woods D. Cortical surface-based meta-analysis of human visuotopic regions from published stereotaxic coordinates. J Vis 2012. [DOI: 10.1167/12.9.523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Deo M, Pandit S, Vaidyanathan R, OConnell R, Milstein M, Musa H, Herron T, Anumonwo J, Jalife J, Berenfeld O. Role of Cytosolic Calcium Diffusion and Sarcolemmal T-Type Calcium Current in Triggered Activity in Purkinje Cells: A Simulation Study. Heart Rhythm 2011. [DOI: 10.1016/j.hrthm.2011.09.032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
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Noujaim SF, Kaur K, Milstein M, Jones JM, Furspan P, Jiang D, Auerbach DS, Herron T, Meisler MH, Jalife J. A null mutation of the neuronal sodium channel NaV1.6 disrupts action potential propagation and excitation-contraction coupling in the mouse heart. FASEB J 2011; 26:63-72. [PMID: 21948246 DOI: 10.1096/fj.10-179770] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Evidence supports the expression of brain-type sodium channels in the heart. Their functional role, however, remains controversial. We used global Na(V)1.6-null mice to test the hypothesis that Na(V)1.6 contributes to the maintenance of propagation in the myocardium and to excitation-contraction (EC) coupling. We demonstrated expression of transcripts encoding full-length Na(V)1.6 in isolated ventricular myocytes and confirmed the striated pattern of Na(V)1.6 fluorescence in myocytes. On the ECG, the PR and QRS intervals were prolonged in the null mice, and the Ca(2+) transients were longer in the null cells. Under patch clamping, at holding potential (HP) = -120 mV, the peak I(Na) was similar in both phenotypes. However, at HP = -70 mV, the peak I(Na) was smaller in the nulls. In optical mapping, at 4 mM [K(+)](o), 17 null hearts showed slight (7%) reduction of ventricular conduction velocity (CV) compared to 16 wild-type hearts. At 12 mM [K(+)](o), CV was 25% slower in a subset of 9 null vs. 9 wild-type hearts. These results highlight the importance of neuronal sodium channels in the heart, whereby Na(V)1.6 participates in EC coupling, and represents an intrinsic depolarizing reserve that contributes to excitation.
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Affiliation(s)
- Sami F Noujaim
- Center for Arrhythmia Research, University of Michigan, Ann Arbor, MI 48108, USA
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15
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Cate A, Kang X, Herron T, Woods D. Part-whole integration of 2D shapes in the hippocampus and the basal ganglia. J Vis 2011. [DOI: 10.1167/11.11.1094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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16
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Vandenboom R, Herron T, Favre E, Albayya FP, Metzger JM. Gene transfer, expression, and sarcomeric incorporation of a headless myosin molecule in cardiac myocytes: evidence for a reserve in myofilament motor function. Am J Physiol Heart Circ Physiol 2010; 300:H574-82. [PMID: 21112946 DOI: 10.1152/ajpheart.00786.2009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The purpose of this study was to implement a living myocyte in vitro model system to test whether a motor domain-deleted headless myosin construct could be incorporated into the sarcomere and affect contractility. To this end we used gene transfer to express a "headless" myosin heavy chain (headless-MHC) in complement with the native full-length myosin motors in the cardiac sarcomere. An NH2-terminal Flag epitope was used for unique detection of the motor domain-deleted headless-MHC. Total MHC content (i.e., headless-MHC+endogenous MHC) remained constant, while expression of the headless-MHC in transduced myocytes increased from 24 to 72 h after gene transfer until values leveled off at 96 h after gene transfer, at which time the headless-MHC comprised ∼20% of total MHC. Moreover, immunofluorescence labeling and confocal imaging confirmed expression and demonstrated incorporation of the headless-MHC in the A band of the cardiac sarcomere. Functional measurements in intact myocytes showed that headless-MHC modestly reduced amplitude of dynamic twitch contractions compared with controls (P<0.05). In chemically permeabilized myocytes, maximum steady-state isometric force and the tension-pCa relationship were unaltered by the headless-MHC. These data suggest that headless-MHC can express to 20% of total myosin and incorporate into the sarcomere yet have modest to no effects on dynamic and steady-state contractile function. This would indicate a degree of functional tolerance in the sarcomere for nonfunctional myosin molecules.
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Affiliation(s)
- Rene Vandenboom
- Integrative Biology and Physiology, University of Minnesota School of Medicine, 6-125 Jackson Hall, 321 Church St. E, Minneapolis, MN 55455, USA
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Cate A, Kang X, Herron T, Yund EW, Woods D. Shape dimensions, perceptual organization and intermodal selective attention: anterior extrastriate fMRI. J Vis 2010. [DOI: 10.1167/10.7.1205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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18
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Chaturvedi RR, Herron T, Simmons R, Shore D, Kumar P, Sethia B, Chua F, Vassiliadis E, Kentish JC. Passive Stiffness of Myocardium From Congenital Heart Disease and Implications for Diastole. Circulation 2010; 121:979-88. [DOI: 10.1161/circulationaha.109.850677] [Citation(s) in RCA: 118] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Rajiv R. Chaturvedi
- From the King’s College London British Heart Foundation Centre (R.R.C., T.H., R.S., E.V., J.C.K.); Royal Brompton Hospital (R.R.C., D.S., P.K., B.S.); and Centre for Respiratory Research, University College (F.C.), London, UK. Dr Chaturvedi is currently at the Division of Cardiology, Hospital for Sick Children, Toronto, Canada. Dr Herron is currently at the Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor. Dr Kumar is currently at the Cardiac Centre, Morriston
| | - Todd Herron
- From the King’s College London British Heart Foundation Centre (R.R.C., T.H., R.S., E.V., J.C.K.); Royal Brompton Hospital (R.R.C., D.S., P.K., B.S.); and Centre for Respiratory Research, University College (F.C.), London, UK. Dr Chaturvedi is currently at the Division of Cardiology, Hospital for Sick Children, Toronto, Canada. Dr Herron is currently at the Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor. Dr Kumar is currently at the Cardiac Centre, Morriston
| | - Robert Simmons
- From the King’s College London British Heart Foundation Centre (R.R.C., T.H., R.S., E.V., J.C.K.); Royal Brompton Hospital (R.R.C., D.S., P.K., B.S.); and Centre for Respiratory Research, University College (F.C.), London, UK. Dr Chaturvedi is currently at the Division of Cardiology, Hospital for Sick Children, Toronto, Canada. Dr Herron is currently at the Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor. Dr Kumar is currently at the Cardiac Centre, Morriston
| | - Darryl Shore
- From the King’s College London British Heart Foundation Centre (R.R.C., T.H., R.S., E.V., J.C.K.); Royal Brompton Hospital (R.R.C., D.S., P.K., B.S.); and Centre for Respiratory Research, University College (F.C.), London, UK. Dr Chaturvedi is currently at the Division of Cardiology, Hospital for Sick Children, Toronto, Canada. Dr Herron is currently at the Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor. Dr Kumar is currently at the Cardiac Centre, Morriston
| | - Pankaj Kumar
- From the King’s College London British Heart Foundation Centre (R.R.C., T.H., R.S., E.V., J.C.K.); Royal Brompton Hospital (R.R.C., D.S., P.K., B.S.); and Centre for Respiratory Research, University College (F.C.), London, UK. Dr Chaturvedi is currently at the Division of Cardiology, Hospital for Sick Children, Toronto, Canada. Dr Herron is currently at the Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor. Dr Kumar is currently at the Cardiac Centre, Morriston
| | - Babulal Sethia
- From the King’s College London British Heart Foundation Centre (R.R.C., T.H., R.S., E.V., J.C.K.); Royal Brompton Hospital (R.R.C., D.S., P.K., B.S.); and Centre for Respiratory Research, University College (F.C.), London, UK. Dr Chaturvedi is currently at the Division of Cardiology, Hospital for Sick Children, Toronto, Canada. Dr Herron is currently at the Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor. Dr Kumar is currently at the Cardiac Centre, Morriston
| | - Felix Chua
- From the King’s College London British Heart Foundation Centre (R.R.C., T.H., R.S., E.V., J.C.K.); Royal Brompton Hospital (R.R.C., D.S., P.K., B.S.); and Centre for Respiratory Research, University College (F.C.), London, UK. Dr Chaturvedi is currently at the Division of Cardiology, Hospital for Sick Children, Toronto, Canada. Dr Herron is currently at the Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor. Dr Kumar is currently at the Cardiac Centre, Morriston
| | - Efstathios Vassiliadis
- From the King’s College London British Heart Foundation Centre (R.R.C., T.H., R.S., E.V., J.C.K.); Royal Brompton Hospital (R.R.C., D.S., P.K., B.S.); and Centre for Respiratory Research, University College (F.C.), London, UK. Dr Chaturvedi is currently at the Division of Cardiology, Hospital for Sick Children, Toronto, Canada. Dr Herron is currently at the Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor. Dr Kumar is currently at the Cardiac Centre, Morriston
| | - Jonathan C. Kentish
- From the King’s College London British Heart Foundation Centre (R.R.C., T.H., R.S., E.V., J.C.K.); Royal Brompton Hospital (R.R.C., D.S., P.K., B.S.); and Centre for Respiratory Research, University College (F.C.), London, UK. Dr Chaturvedi is currently at the Division of Cardiology, Hospital for Sick Children, Toronto, Canada. Dr Herron is currently at the Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor. Dr Kumar is currently at the Cardiac Centre, Morriston
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Kang X, Herron T, Woods D. Is Ellipsoidal Area Ratio Better Than FA? A Validation Study. Neuroimage 2009. [DOI: 10.1016/s1053-8119(09)70543-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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20
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Day SM, Coutu P, Wang W, Herron T, Turner I, Shillingford M, Lacross NC, Converso KL, Piao L, Li J, Lopatin AN, Metzger JM. Cardiac-directed parvalbumin transgene expression in mice shows marked heart rate dependence of delayed Ca2+ buffering action. Physiol Genomics 2008; 33:312-22. [PMID: 18334547 DOI: 10.1152/physiolgenomics.00302.2007] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Relaxation abnormalities are prevalent in heart failure and contribute to clinical outcomes. Disruption of Ca2+ homeostasis in heart failure delays relaxation by prolonging the intracellular Ca2+ transient. We sought to speed cardiac relaxation in vivo by cardiac-directed transgene expression of parvalbumin (Parv), a cytosolic Ca2+ buffer normally expressed in fast-twitch skeletal muscle. A key feature of Parv's function resides in its Ca2+/Mg2+ binding affinities that account for delayed Ca2+ buffering in response to the intracellular Ca2+ transient. Cardiac Parv expression decreased sarcoplasmic reticulum Ca2+ content without otherwise altering intracellular Ca2+ homeostasis. At high physiological mouse heart rates in vivo, Parv modestly accelerated relaxation without affecting cardiac morphology or systolic function. Ex vivo pacing of the isolated heart revealed a marked heart rate dependence of Parv's delayed Ca2+ buffering effects on myocardial performance. As the pacing frequency was lowered (7 to 2.5 Hz), the relaxation rates increased in Parv hearts. However, as pacing rates approached the dynamic range in humans, Parv hearts demonstrated decreased contractility, consistent with Parv buffering systolic Ca2+. Mathematical modeling and in vitro studies provide the underlying mechanism responsible for the frequency-dependent fractional Ca2+ buffering action of Parv. Future studies directed toward refining the dose and frequency-response relationships of Parv in the heart or engineering novel Parv-based Ca2+ buffers with modified Mg2+ and Ca2+ affinities to limit systolic Ca2+ buffering may hold promise for the development of new therapies to remediate relaxation abnormalities in heart failure.
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Affiliation(s)
- Sharlene M Day
- Department of Internal Medicine, University of Michigan Medical Center, Ann Arbor, Michigan 48109-0644, USA
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Abstract
Between 1956 and 1978, nine patients with solitary plasmacytoma of bone (SPB) and seven with extramedullary plasmacytoma (EMP) were treated at the University of Washington Hospital and Swedish Tumor Institute. All but one patient had local radiotherapy. In the SPB group, six of nine patients progressed to multiple myeloma (MM) and five died of disease within three years after dissemination. Three of the nine patients are alive at 5, 8, and 16 years, respectively. In the EMP group, none of the seven patients progressed to MM. Five are alive 16 months to 23 years after radiotherapy. Since there are no reliable criteria for prospectively distinguishing true solitary plasmacytoma from occult MM, all patients with apparently isolated plasmacytoma should receive local radiotherapy with curative intent.
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Deliere HM, Herron T. Impact of the day of admission on length of stay in a community general hospital. J Okla State Med Assoc 1978; 71:158-60. [PMID: 660321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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