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Markandran K, Yu H, Song W, Lam DTUH, Madathummal MC, Ferenczi MA. Functional and Molecular Characterisation of Heart Failure Progression in Mice and the Role of Myosin Regulatory Light Chains in the Recovery of Cardiac Muscle Function. Int J Mol Sci 2021; 23:ijms23010088. [PMID: 35008512 PMCID: PMC8745055 DOI: 10.3390/ijms23010088] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Revised: 12/07/2021] [Accepted: 12/14/2021] [Indexed: 02/07/2023] Open
Abstract
Heart failure (HF) as a result of myocardial infarction (MI) is a major cause of fatality worldwide. However, the cause of cardiac dysfunction succeeding MI has not been elucidated at a sarcomeric level. Thus, studying the alterations within the sarcomere is necessary to gain insights on the fundamental mechansims leading to HF and potentially uncover appropriate therapeutic targets. Since existing research portrays regulatory light chains (RLC) to be mediators of cardiac muscle contraction in both human and animal models, its role was further explored In this study, a detailed characterisation of the physiological changes (i.e., isometric force, calcium sensitivity and sarcomeric protein phosphorylation) was assessed in an MI mouse model, between 2D (2 days) and 28D post-MI, and the changes were related to the phosphorylation status of RLCs. MI mouse models were created via complete ligation of left anterior descending (LAD) coronary artery. Left ventricular (LV) papillary muscles were isolated and permeabilised for isometric force and Ca2+ sensitivity measurement, while the LV myocardium was used to assay sarcomeric proteins’ (RLC, troponin I (TnI) and myosin binding protein-C (MyBP-C)) phosphorylation levels and enzyme (myosin light chain kinase (MLCK), zipper interacting protein kinase (ZIPK) and myosin phosphatase target subunit 2 (MYPT2)) expression levels. Finally, the potential for improving the contractility of diseased cardiac papillary fibres via the enhancement of RLC phosphorylation levels was investigated by employing RLC exchange methods, in vitro. RLC phosphorylation and isometric force potentiation were enhanced in the compensatory phase and decreased in the decompensatory phase of HF failure progression, respectively. There was no significant time-lag between the changes in RLC phosphorylation and isometric force during HF progression, suggesting that changes in RLC phosphorylation immediately affect force generation. Additionally, the in vitro increase in RLC phosphorylation levels in 14D post-MI muscle segments (decompensatory stage) enhanced its force of isometric contraction, substantiating its potential in HF treatment. Longitudinal observation unveils potential mechanisms involving MyBP-C and key enzymes regulating RLC phosphorylation, such as MLCK and MYPT2 (subunit of MLCP), during HF progression. This study primarily demonstrates that RLC phosphorylation is a key sarcomeric protein modification modulating cardiac function. This substantiates the possibility of using RLCs and their associated enzymes to treat HF.
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Affiliation(s)
- Kasturi Markandran
- Lee Kong Chian School of Medicine, Nanyang Technological University, Experimental Medicine Building, 59 Nanyang Drive, Singapore 636921, Singapore; (K.M.); (H.Y.); (W.S.); (D.T.U.H.L.); (M.C.M.)
| | - Haiyang Yu
- Lee Kong Chian School of Medicine, Nanyang Technological University, Experimental Medicine Building, 59 Nanyang Drive, Singapore 636921, Singapore; (K.M.); (H.Y.); (W.S.); (D.T.U.H.L.); (M.C.M.)
| | - Weihua Song
- Lee Kong Chian School of Medicine, Nanyang Technological University, Experimental Medicine Building, 59 Nanyang Drive, Singapore 636921, Singapore; (K.M.); (H.Y.); (W.S.); (D.T.U.H.L.); (M.C.M.)
| | - Do Thuy Uyen Ha Lam
- Lee Kong Chian School of Medicine, Nanyang Technological University, Experimental Medicine Building, 59 Nanyang Drive, Singapore 636921, Singapore; (K.M.); (H.Y.); (W.S.); (D.T.U.H.L.); (M.C.M.)
- Laboratory of Precision Disease Therapeutics, Genome Institute of Singapore, 60 Biopolis Street, Singapore 138672, Singapore
- Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, 10 Medical Drive, Singapore 117597, Singapore
| | - Mufeeda Changaramvally Madathummal
- Lee Kong Chian School of Medicine, Nanyang Technological University, Experimental Medicine Building, 59 Nanyang Drive, Singapore 636921, Singapore; (K.M.); (H.Y.); (W.S.); (D.T.U.H.L.); (M.C.M.)
- A*STAR Microscopy Platform—Electron Microscopy, 61 Biopolis Drive, Proteos, Singapore 138673, Singapore
| | - Michael A. Ferenczi
- Lee Kong Chian School of Medicine, Nanyang Technological University, Experimental Medicine Building, 59 Nanyang Drive, Singapore 636921, Singapore; (K.M.); (H.Y.); (W.S.); (D.T.U.H.L.); (M.C.M.)
- Brunel Medical School, Brunel University London, Kingston Lane, Uxbridge UB8 3PH, UK
- Correspondence:
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Kopylova GV, Matyushenko AM, Berg VY, Levitsky DI, Bershitsky SY, Shchepkin DV. Acidosis modifies effects of phosphorylated tropomyosin on the actin-myosin interaction in the myocardium. J Muscle Res Cell Motil 2021; 42:343-353. [PMID: 33389411 DOI: 10.1007/s10974-020-09593-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 12/05/2020] [Indexed: 12/15/2022]
Abstract
Phosphorylation of α-tropomyosin (Tpm1.1), a predominant Tpm isoform in the myocardium, is one of the regulatory mechanisms of the heart contractility. The Tpm 1.1 molecule has one site of phosphorylation, Ser283. The degree of the Tpm phosphorylation decreases with age and also changes in heart pathologies. Myocardial pathologies, in particular ischemia, are usually accompanied by pH lowering in the cardiomyocyte cytosol. We studied the effects of acidosis on the structural and functional properties of the pseudo-phosphorylated form of Tpm1.1 with the S283D substitution. We found that in acidosis, the interaction of the N- and C-ends of the S283D Tpm molecules decreases, whereas that of WT Tpm does not change. The pH lowering increased thermostability of the complex of F-actin with S283D Tpm to a greater extent than with WT Tpm. Using an in vitro motility assay with NEM- modified myosin as a load, we assessed the effect of the Tpm pseudo-phosphorylation on the force of the actin-myosin interaction. In acidosis, the force generated by myosin in the interaction with thin filaments containing S283D Tpm was higher than with those containing WT Tpm. Also, the pseudo-phosphorylation increased the myosin ability to resist a load. We conclude that ischemia changes the effect of the phosphorylated Tpm on the contractile function of the myocardium.
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Affiliation(s)
- Galina V Kopylova
- Institute of Immunology and Physiology, Russian Academy of Sciences, 620049, Yekaterinburg, Russia.
| | - Alexander M Matyushenko
- Research Center of Biotechnology, A.N. Bach Institute of Biochemistry, Russian Academy of Sciences, 119071, Moscow, Russia
| | - Valentina Y Berg
- Institute of Immunology and Physiology, Russian Academy of Sciences, 620049, Yekaterinburg, Russia
| | - Dmitrii I Levitsky
- Research Center of Biotechnology, A.N. Bach Institute of Biochemistry, Russian Academy of Sciences, 119071, Moscow, Russia
| | - Sergey Y Bershitsky
- Institute of Immunology and Physiology, Russian Academy of Sciences, 620049, Yekaterinburg, Russia
| | - Daniil V Shchepkin
- Institute of Immunology and Physiology, Russian Academy of Sciences, 620049, Yekaterinburg, Russia
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Azimzadeh O, Azizova T, Merl-Pham J, Blutke A, Moseeva M, Zubkova O, Anastasov N, Feuchtinger A, Hauck SM, Atkinson MJ, Tapio S. Chronic Occupational Exposure to Ionizing Radiation Induces Alterations in the Structure and Metabolism of the Heart: A Proteomic Analysis of Human Formalin-Fixed Paraffin-Embedded (FFPE) Cardiac Tissue. Int J Mol Sci 2020; 21:ijms21186832. [PMID: 32957660 PMCID: PMC7555548 DOI: 10.3390/ijms21186832] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 09/14/2020] [Accepted: 09/14/2020] [Indexed: 12/23/2022] Open
Abstract
Epidemiological studies on workers employed at the Mayak plutonium enrichment plant have demonstrated an association between external gamma ray exposure and an elevated risk of ischemic heart disease (IHD). In a previous study using fresh-frozen post mortem samples of the cardiac left ventricle of Mayak workers and non-irradiated controls, we observed radiation-induced alterations in the heart proteome, mainly downregulation of mitochondrial and structural proteins. As the control group available at that time was younger than the irradiated group, we could not exclude age as a confounding factor. To address this issue, we have now expanded our study to investigate additional samples using archival formalin-fixed paraffin-embedded (FFPE) tissue. Importantly, the control group studied here is older than the occupationally exposed (>500 mGy) group. Label-free quantitative proteomics analysis showed that proteins involved in the lipid metabolism, sirtuin signaling, mitochondrial function, cytoskeletal organization, and antioxidant defense were the most affected. A histopathological analysis elucidated large foci of fibrotic tissue, myocardial lipomatosis and lymphocytic infiltrations in the irradiated samples. These data highlight the suitability of FFPE material for proteomics analysis. The study confirms the previous results emphasizing the role of adverse metabolic changes in the radiation-associated IHD. Most importantly, it excludes age at the time of death as a confounding factor.
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Affiliation(s)
- Omid Azimzadeh
- Helmholtz Zentrum München—German Research Centre for Environmental Health GmbH, Institute of Radiation Biology, 85764 Neuherberg, Germany; (N.A.); (M.J.A.); (S.T.)
- Correspondence: ; Tel.: +49-89-3187-3887
| | - Tamara Azizova
- Southern Urals Biophysics Institute (SUBI), Russian Federation, 456780 Ozyorsk, Russia; (T.A.); (M.M.); (O.Z.)
| | - Juliane Merl-Pham
- Helmholtz Zentrum München—German Research Centre for Environmental Health, Research Unit Protein Science, 80939 Munich, Germany; (J.M.-P.); (S.M.H.)
| | - Andreas Blutke
- Helmholtz Zentrum München—German Research Centre for Environmental Health GmbH, Research Unit Analytical Pathology, 85764 Neuherberg, Germany; (A.B.); (A.F.)
| | - Maria Moseeva
- Southern Urals Biophysics Institute (SUBI), Russian Federation, 456780 Ozyorsk, Russia; (T.A.); (M.M.); (O.Z.)
| | - Olga Zubkova
- Southern Urals Biophysics Institute (SUBI), Russian Federation, 456780 Ozyorsk, Russia; (T.A.); (M.M.); (O.Z.)
| | - Natasa Anastasov
- Helmholtz Zentrum München—German Research Centre for Environmental Health GmbH, Institute of Radiation Biology, 85764 Neuherberg, Germany; (N.A.); (M.J.A.); (S.T.)
| | - Annette Feuchtinger
- Helmholtz Zentrum München—German Research Centre for Environmental Health GmbH, Research Unit Analytical Pathology, 85764 Neuherberg, Germany; (A.B.); (A.F.)
| | - Stefanie M. Hauck
- Helmholtz Zentrum München—German Research Centre for Environmental Health, Research Unit Protein Science, 80939 Munich, Germany; (J.M.-P.); (S.M.H.)
| | - Michael J. Atkinson
- Helmholtz Zentrum München—German Research Centre for Environmental Health GmbH, Institute of Radiation Biology, 85764 Neuherberg, Germany; (N.A.); (M.J.A.); (S.T.)
- Chair of Radiation Biology, Technical University of Munich, 81675 Munich, Germany
| | - Soile Tapio
- Helmholtz Zentrum München—German Research Centre for Environmental Health GmbH, Institute of Radiation Biology, 85764 Neuherberg, Germany; (N.A.); (M.J.A.); (S.T.)
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The Role of Signaling Pathways of Inflammation and Oxidative Stress in Development of Senescence and Aging Phenotypes in Cardiovascular Disease. Cells 2019; 8:cells8111383. [PMID: 31689891 PMCID: PMC6912541 DOI: 10.3390/cells8111383] [Citation(s) in RCA: 155] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Revised: 10/24/2019] [Accepted: 10/28/2019] [Indexed: 12/28/2022] Open
Abstract
The ASK1-signalosome→p38 MAPK and SAPK/JNK signaling networks promote senescence (in vitro) and aging (in vivo, animal models and human cohorts) in response to oxidative stress and inflammation. These networks contribute to the promotion of age-associated cardiovascular diseases of oxidative stress and inflammation. Furthermore, their inhibition delays the onset of these cardiovascular diseases as well as senescence and aging. In this review we focus on whether the (a) ASK1-signalosome, a major center of distribution of reactive oxygen species (ROS)-mediated stress signals, plays a role in the promotion of cardiovascular diseases of oxidative stress and inflammation; (b) The ASK1-signalosome links ROS signals generated by dysfunctional mitochondrial electron transport chain complexes to the p38 MAPK stress response pathway; (c) the pathway contributes to the sensitivity and vulnerability of aged tissues to diseases of oxidative stress; and (d) the importance of inhibitors of these pathways to the development of cardioprotection and pharmaceutical interventions. We propose that the ASK1-signalosome regulates the progression of cardiovascular diseases. The resultant attenuation of the physiological characteristics of cardiomyopathies and aging by inhibition of the ASK1-signalosome network lends support to this conclusion. Importantly the ROS-mediated activation of the ASK1-signalosome p38 MAPK pathway suggests it is a major center of dissemination of the ROS signals that promote senescence, aging and cardiovascular diseases. Pharmacological intervention is, therefore, feasible through the continued identification of potent, non-toxic small molecule inhibitors of either ASK1 or p38 MAPK activity. This is a fruitful future approach to the attenuation of physiological aspects of mammalian cardiomyopathies and aging.
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Is there an effect of ischemic conditioning on myocardial contractile function following acute myocardial ischemia/reperfusion injury? Biochim Biophys Acta Mol Basis Dis 2019; 1865:822-830. [PMID: 30660684 DOI: 10.1016/j.bbadis.2018.12.020] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 12/18/2018] [Accepted: 12/19/2018] [Indexed: 10/27/2022]
Abstract
Ischemic conditioning induces cardioprotection; the final infarct size following a myocardial ischemic event is reduced. However, whether ischemic conditioning has long-term beneficial effects on myocardial contractile function following such an ischemic event needs further elucidation. To date, ex vivo studies have shown that ischemic conditioning improves the contractile recovery of isolated ventricular papillary muscle or atrial trabeculae following simulated ischemia. However, in vivo animal studies and studies in patients undergoing elective cardiac surgery show conflicting results. At the subcellular level, it is known that ischemic conditioning improved energy metabolism, preserved mitochondrial respiration, ATP production, and Ca2+ homeostasis in isolated mitochondria from the myocardium. Ischemic conditioning also presents with post-translational modifications of proteins in the contractile machinery of the myocardium. The beneficial effects on myocardial contractile function need further elucidation. This article is part of a Special Issue entitled: The power of metabolism: Linking energy supply and demand to contractile function edited by Torsten Doenst, Michael Schwarzer and Christine Des Rosiers.
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Cuello F, Wittig I, Lorenz K, Eaton P. Oxidation of cardiac myofilament proteins: Priming for dysfunction? Mol Aspects Med 2018; 63:47-58. [PMID: 30130564 DOI: 10.1016/j.mam.2018.08.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Revised: 08/13/2018] [Accepted: 08/17/2018] [Indexed: 02/07/2023]
Abstract
Oxidants are produced endogenously and can react with and thereby post-translationally modify target proteins. They have been implicated in the redox regulation of signal transduction pathways conferring protection, but also in mediating oxidative stress and causing damage. The difference is that in scenarios of injury the amount of oxidants generated is higher and/or the duration of oxidant exposure sustained. In the cardiovascular system, oxidants are important for blood pressure homeostasis, for unperturbed cardiac function and also contribute to the observed protection during ischemic preconditioning. In contrast, oxidative stress accompanies all major cardiovascular pathologies and has been attributed to mediate contractile dysfunction in part by inducing oxidative modifications in myofilament proteins. However, the proportion to which oxidative modifications of contractile proteins are beneficial or causatively mediate disease progression needs to be carefully reconsidered. These antithetical aspects will be discussed in this review with special focus on direct oxidative post-translational modifications of myofilament proteins that have been described to occur in vivo and to regulate actin-myosin interactions in the cardiac myocyte sarcomere, the methodologies for detection of oxidative post-translational modifications in target proteins and the feasibility of antioxidant therapy strategies as a potential treatment for cardiac disorders.
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Affiliation(s)
- Friederike Cuello
- Institute of Experimental Pharmacology and Toxicology, Cardiovascular Research Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; DZHK (German Center for Cardiovascular Research), Partner Site Hamburg/Kiel/Lübeck, Germany.
| | - Ilka Wittig
- Functional Proteomics, SFB 815 Core Unit, Faculty of Medicine, Johann Wolfgang Goethe University, Frankfurt am Main, Germany; DZHK (German Center for Cardiovascular Research), Partner Site Rhine-Main, Germany
| | - Kristina Lorenz
- Comprehensive Heart Failure Center, Würzburg, Leibniz-Institut für Analytische Wissenschaften-ISAS-e.V. Dortmund, West German Heart and Vascular Center, Essen, Germany
| | - Philip Eaton
- King's British Heart Foundation Centre, King's College London, UK
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Kopylova G, Nabiev S, Shchepkin D, Bershitsky S. Carbonylation of atrial myosin prolongs its interaction with actin. EUROPEAN BIOPHYSICS JOURNAL : EBJ 2018; 47:11-18. [PMID: 28409219 DOI: 10.1007/s00249-017-1209-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Revised: 03/22/2017] [Accepted: 04/07/2017] [Indexed: 11/26/2022]
Abstract
Carbonylation induced by hyperthyroidism suppresses force generation of skeletal myosin and sliding velocity of actin filaments in an in vitro motility assay. However, its effects on cardiac myosin at the molecular level have not been studied. Hyperthyroidism induces a change in expression of myosin heavy chains in ventricles, which may mask the effect of oxidation. In contrast to ventricular myosin, expression of myosin heavy chains in the atrium does not change upon hyperthyroidism and enables investigation of the effect of oxidation on cardiac myosin. We studied the influence of carbonylation, a type of protein oxidation, on the motor function of atrial myosin and Ca2+ regulation of actin-myosin interaction at the level of isolated proteins and single molecules using an in vitro motility assay and an optical trap. Carbonylation of atrial myosin prolonged its attached state on actin and decreased maximal sliding velocity of thin filaments over this myosin but did not affect the calcium sensitivity of the velocity. The results indicate that carbonylation of atrial myosin induced by hyperthyroidism can be a rate-limiting factor of atrium contractility and so participates in the genesis of heart failure in hyperthyroidism.
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Affiliation(s)
- G Kopylova
- Institute of Immunology and Physiology, Russian Academy of Sciences, Pervomayskaya ul. 106, Yekaterinburg, 620049, Russia.
| | - S Nabiev
- Institute of Immunology and Physiology, Russian Academy of Sciences, Pervomayskaya ul. 106, Yekaterinburg, 620049, Russia
| | - D Shchepkin
- Institute of Immunology and Physiology, Russian Academy of Sciences, Pervomayskaya ul. 106, Yekaterinburg, 620049, Russia
| | - S Bershitsky
- Institute of Immunology and Physiology, Russian Academy of Sciences, Pervomayskaya ul. 106, Yekaterinburg, 620049, Russia
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Woodward M, Previs MJ, Mader TJ, Debold EP. Modifications of myofilament protein phosphorylation and function in response to cardiac arrest induced in a swine model. Front Physiol 2015; 6:199. [PMID: 26236240 PMCID: PMC4503891 DOI: 10.3389/fphys.2015.00199] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Accepted: 06/29/2015] [Indexed: 12/27/2022] Open
Abstract
Cardiac arrest is a prevalent condition with a poor prognosis, attributable in part to persistent myocardial dysfunction following resuscitation. The molecular basis of this dysfunction remains unclear. We induced cardiac arrest in a porcine model of acute sudden death and assessed the impact of ischemia and reperfusion on the molecular function of isolated cardiac contractile proteins. Cardiac arrest was electrically induced, left untreated for 12 min, and followed by a resuscitation protocol. With successful resuscitations, the heart was reperfused for 2 h (IR2) and the muscle harvested. In failed resuscitations, tissue samples were taken following the failed efforts (IDNR). Actin filament velocity, using myosin isolated from IR2 or IDNR cardiac tissue, was nearly identical to myosin from the control tissue in a motility assay. However, both maximal velocity (25% faster than control) and calcium sensitivity (pCa50 6.57 ± 0.04 IDNR vs. 6.34 ± 0.07 control) were significantly (p < 0.05) enhanced using native thin filaments (actin+troponin+tropomyosin) from IDNR samples, suggesting that the enhanced velocity is mediated through an alteration in muscle regulatory proteins (troponin+tropomyosin). Mass spectrometry analysis showed that only samples from the IR2 had an increase in total phosphorylation levels of troponin (Tn) and tropomyosin (Tm), but both IR2 and IDNR samples demonstrated a significant shift from mono-phosphorylated to bis-phosphorylated forms of the inhibitory subunit of Tn (TnI) compared to control. This suggests that the shift to bis-phosphorylation of TnI is associated with the enhanced function in IDNR, but this effect may be attenuated when phosphorylation of Tm is increased in tandem, as observed for IR2. There are likely many other molecular changes induced following cardiac arrest, but to our knowledge, these data provide the first evidence that this form cardiac arrest can alter the in vitro function of the cardiac contractile proteins.
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Affiliation(s)
- Mike Woodward
- Molecular and Cellular Biology Graduate Program, University of Massachusetts Amherst, MA, USA
| | - Michael J Previs
- Department of Molecular Physiology and Biophysics, University of Vermont Burlington, VT, USA
| | - Timothy J Mader
- Department of Emergency Medicine, Baystate Medical Center/Tufts University School of Medicine Springfield, MA, USA
| | - Edward P Debold
- Molecular and Cellular Biology Graduate Program, University of Massachusetts Amherst, MA, USA ; Muscle Biophysics Lab, Department of Kinesiology, University of Massachusetts Amherst, MA, USA
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Balogh A, Santer D, Pásztor ET, Tóth A, Czuriga D, Podesser BK, Trescher K, Jaquet K, Erdodi F, Edes I, Papp Z. Myofilament protein carbonylation contributes to the contractile dysfunction in the infarcted LV region of mouse hearts. Cardiovasc Res 2013; 101:108-19. [PMID: 24127233 DOI: 10.1093/cvr/cvt236] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
AIMS The region-specific mechanical function of left ventricular (LV) murine cardiomyocytes and the role of phosphorylation and oxidative modifications of myofilament proteins were investigated in the process of post-myocardial infarction (MI) remodelling 10 weeks after ligation of the left anterior descending (LAD) coronary artery. METHODS AND RESULTS Permeabilized murine cardiomyocytes from the remaining anterior and a remote non-infarcted inferior LV area were compared with those of non-infarcted age-matched controls. Myofilament phosphorylation, sulfhydryl (SH) oxidation, and carbonylation were also assayed. Ca(2+) sensitivity of force production was significantly lower in the anterior wall (pCa50: 5.81 ± 0.03, means ± SEM, at 2.3 µm sarcomere length) than that in the controls (pCa50: 5.91 ± 0.02) or in the MI inferior area (pCa50: 5.88 ± 0.02). The level of troponin I phosphorylation was lower and that of myofilament protein SH oxidation was higher in the anterior location relative to controls, but these changes did not explain the differences in Ca(2+) sensitivities. On the other hand, significantly higher carbonylation levels, [e.g. in myosin heavy chain (MHC) and actin] were observed in the MI anterior wall [carbonylation index (CI), CIMHC: 2.06 ± 0.46, CIactin: 1.46 ± 0.18] than in the controls (CI: 1). In vitro Fenton-based myofilament carbonylation in the control cardiomyocytes also decreased the Ca(2+) sensitivity of force production irrespective of the phosphorylation status of the myofilaments. Furthermore, the Ca(2+) sensitivity correlated strongly with myofilament carbonylation levels in all investigated samples. CONCLUSION Post-MI myocardial remodelling involves increased myofibrillar protein carbonylation and decreased Ca(2+) sensitivity of force production, leading potentially to contractile dysfunction in the remaining cardiomyocytes of the infarcted area.
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Affiliation(s)
- Agnes Balogh
- Division of Clinical Physiology, Research Center for Molecular Medicine, Institute of Cardiology, Faculty of Medicine, Medical and Health Science Center, University of Debrecen, Móricz Zs. krt. 22, Debrecen H-4032, Hungary
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Tropomyosin Ser-283 pseudo-phosphorylation slows myofibril relaxation. Arch Biochem Biophys 2012; 535:30-8. [PMID: 23232082 DOI: 10.1016/j.abb.2012.11.010] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2012] [Revised: 11/21/2012] [Accepted: 11/22/2012] [Indexed: 12/15/2022]
Abstract
Tropomyosin (Tm) is a central protein in the Ca(2+) regulation of striated muscle. The αTm isoform undergoes phosphorylation at serine residue 283. While the biochemical and steady-state muscle function of muscle purified Tm phosphorylation have been explored, the effects of Tm phosphorylation on the dynamic properties of muscle contraction and relaxation are unknown. To investigate the kinetic regulatory role of αTm phosphorylation we expressed and purified native N-terminal acetylated Ser-283 wild-type, S283A phosphorylation null and S283D pseudo-phosphorylation Tm mutants in insect cells. Purified Tm's regulate thin filaments similar to that reported for muscle purified Tm. Steady-state Ca(2+) binding to troponin C (TnC) in reconstituted thin filaments did not differ between the 3 Tm's, however disassociation of Ca(2+) from filaments containing pseudo-phosphorylated Tm was slowed compared to wild-type Tm. Replacement of pseudo-phosphorylated Tm into myofibrils similarly prolonged the slow phase of relaxation and decreased the rate of the fast phase without altering activation kinetics. These data demonstrate that Tm pseudo-phosphorylation slows deactivation of the thin filament and muscle force relaxation dynamics in the absence of dynamic and steady-state effects on muscle activation. This supports a role for Tm as a key protein in the regulation of muscle relaxation dynamics.
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Chan KYY, Zhou L, Xiang P, Li K, Ng PC, Wang CC, Li M, Pong NH, Tu L, Deng H, Kong CKL, Sung RYT. Thrombopoietin improved ventricular function and regulated remodeling genes in a rat model of myocardial infarction. Int J Cardiol 2012; 167:2546-54. [PMID: 22770769 DOI: 10.1016/j.ijcard.2012.06.038] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2011] [Revised: 05/03/2012] [Accepted: 06/09/2012] [Indexed: 12/26/2022]
Abstract
BACKGROUND Thrombopoietin (TPO) protects against heart damages by doxorubicin-induced cardiomyopathy in animal models. We aimed to investigate the therapeutic efficacy of TPO for treatment of myocardial infarction (MI) in a rat model and explored the mechanisms in terms of the genome-wide transcriptional profile, TPO downstream protein signals, and bone marrow endothelial progenitor cells (EPCs). METHODS Sprague-Dawley rats were divided into 3 groups: Sham-operated, MI (permanent ligation of the left coronary artery) and MI+TPO. Three doses of TPO were administered weekly for 2 weeks, and outcomes were assessed at 4 or 8 weeks post-injury. RESULTS AND CONCLUSIONS TPO treatment significantly improved left ventricular function, hemodynamic parameters, myocardium morphology, neovascularization and infarct size. MI damage upregulated a large cohort of gene expressions in the infarct border zone, including those functioned in cytoskeleton organization, vascular and matrix remodeling, muscle development, cell cycling and ion transport. TPO treatment significantly reversed these modulations. While phosphorylation of janus kinase 2 (JAK2), signal transducer and activator of transcription 3 (STAT3) and protein kinase B (AKT) was modified in MI animals, TPO treatment regulated phosphorylation of STAT3 and extracellular signal-regulated kinases (ERK), and bone morphogenetic protein 1 (BMP1) protein level. TPO also increased EPC colonies in the bone marrow of MI animals. Our data showed that TPO alleviated damages of heart tissues from MI insults, possibly mediated by multi-factorial mechanisms including suppression of over-reacted ventricular remodeling, regulation of TPO downstream signals and mobilization of endothelial progenitor cells. TPO could be developed for treatment of cardiac damages.
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Perjés Á, Kubin A, Kónyi A, Szabados S, Cziráki A, Skoumal R, Ruskoaho H, Szokodi I. Physiological regulation of cardiac contractility by endogenous reactive oxygen species. Acta Physiol (Oxf) 2012; 205:26-40. [PMID: 22463609 DOI: 10.1111/j.1748-1716.2012.02391.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Increased production of reactive oxygen species (ROS) has been linked to the pathogenesis of congestive heart failure. However, emerging evidence suggests the involvement of ROS in the regulation of various physiological cellular processes in the myocardium. In this review, we summarize the latest findings regarding the role of ROS in the acute regulation of cardiac contractility. We discuss ROS-dependent modulation of the inotropic responses to G protein-coupled receptor agonists (e.g. β-adrenergic receptor agonists and endothelin-1), the potential cellular sources of ROS (e.g. NAD(P)H oxidases and mitochondria) and the proposed end-targets and signalling pathways by which ROS affect contractility. Accumulating new data supports the fundamental role of endogenously generated ROS to regulate cardiac function under physiological conditions.
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Affiliation(s)
| | - A.M. Kubin
- Department of Pharmacology and Toxicology; Institute of Biomedicine; Biocenter Oulu; University of Oulu; Oulu; Finland
| | - A. Kónyi
- Heart Institute; Medical School; University of Pécs; Pécs; Hungary
| | - S. Szabados
- Heart Institute; Medical School; University of Pécs; Pécs; Hungary
| | - A. Cziráki
- Heart Institute; Medical School; University of Pécs; Pécs; Hungary
| | - R. Skoumal
- Department of Pharmacology and Toxicology; Institute of Biomedicine; Biocenter Oulu; University of Oulu; Oulu; Finland
| | - H. Ruskoaho
- Department of Pharmacology and Toxicology; Institute of Biomedicine; Biocenter Oulu; University of Oulu; Oulu; Finland
| | - I. Szokodi
- Heart Institute; Medical School; University of Pécs; Pécs; Hungary
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13
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Perjés Á, Kubin A, Kónyi A, Szabados S, Cziráki A, Skoumal R, Ruskoaho H, Szokodi I. Physiological regulation of cardiac contractility by endogenous reactive oxygen species. Acta Physiol (Oxf) 2012. [DOI: 10.1111/j.1748-1716.2011.02391.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
| | - A.M. Kubin
- Department of Pharmacology and Toxicology; Institute of Biomedicine; Biocenter Oulu; University of Oulu; Oulu; Finland
| | - A. Kónyi
- Heart Institute; Medical School; University of Pécs; Pécs; Hungary
| | - S. Szabados
- Heart Institute; Medical School; University of Pécs; Pécs; Hungary
| | - A. Cziráki
- Heart Institute; Medical School; University of Pécs; Pécs; Hungary
| | - R. Skoumal
- Department of Pharmacology and Toxicology; Institute of Biomedicine; Biocenter Oulu; University of Oulu; Oulu; Finland
| | - H. Ruskoaho
- Department of Pharmacology and Toxicology; Institute of Biomedicine; Biocenter Oulu; University of Oulu; Oulu; Finland
| | - I. Szokodi
- Heart Institute; Medical School; University of Pécs; Pécs; Hungary
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14
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Avner BS, Shioura KM, Scruggs SB, Grachoff M, Geenen DL, Helseth DL, Farjah M, Goldspink PH, Solaro RJ. Myocardial infarction in mice alters sarcomeric function via post-translational protein modification. Mol Cell Biochem 2011; 363:203-15. [PMID: 22160857 DOI: 10.1007/s11010-011-1172-z] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2011] [Accepted: 11/23/2011] [Indexed: 01/17/2023]
Abstract
Myocardial physiology in the aftermath of myocardial infarction (MI) before remodeling is an under-explored area of investigation. Here, we describe the effects of MI on the cardiac sarcomere with focus on the possible contributions of reactive oxygen species. We surgically induced MI in 6-7-month-old female CD1 mice by ligation of the left anterior descending coronary artery. Data were collected 3-4 days after MI or sham (SH) surgery. MI hearts demonstrated ventricular dilatation and systolic dysfunction upon echo cardiographic analysis. Sub-maximum Ca-activated tension in detergent-extracted fiber bundles from papillary muscles increased significantly in the preparations from MI hearts. Ca(2+) sensitivity increased after MI, whereas cooperativity of activation decreased. To assess myosin enzymatic integrity we measured splitting of Ca-ATP in myofibrillar preparations, which demonstrated a decline in Ca-ATPase activity of myofilament myosin. Biochemical analysis demonstrated post-translational modification of sarcomeric proteins. Phosphorylation of cardiac troponin I and myosin light chain 2 was reduced after MI in papillary samples, as measured using a phospho-specific stain. Tropomyosin was oxidized after MI, forming disulfide products detectable by diagonal non-reducing-reducing SDS-PAGE. Our analysis of myocardial protein oxidation post-MI also demonstrated increased S-glutathionylation. We functionally linked protein oxidation with sarcomere function by treating skinned fibers with the sulfhydryl reducing agent dithiothreitol, which reduced Ca(2+) sensitivity in MI, but not SH, samples. Our data indicate important structural and functional alterations to the cardiac sarcomere after MI, and the contribution of protein oxidation to this process.
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Affiliation(s)
- Benjamin S Avner
- Department of Physiology and Biophysics, (M/C 901), College of Medicine, University of Illinois at Chicago, 835 S. Wolcott Ave., Chicago, IL 60612-7342, USA
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15
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Kean TJ, Duesler L, Young RG, Dadabayev A, Olenyik A, Penn M, Wagner J, Fink DJ, Caplan AI, Dennis JE. Development of a peptide-targeted, myocardial ischemia-homing, mesenchymal stem cell. J Drug Target 2011; 20:23-32. [DOI: 10.3109/1061186x.2011.622398] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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16
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Rao VS, Clobes AM, Guilford WH. Force spectroscopy reveals multiple "closed states" of the muscle thin filament. J Biol Chem 2011; 286:24135-41. [PMID: 21597115 DOI: 10.1074/jbc.m110.167957] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Tropomyosin (Tm) plays a critical role in regulating the contraction of striated muscle. The three-state model of activation posits that Tm exists in three positions on the thin filament: "blocked" in the absence of calcium when myosin cannot bind, "closed" when calcium binds troponin and Tm partially covers the myosin binding site, and "open" after myosin binding forces Tm completely off neighboring sites. However, we recently showed that actin filaments decorated with phosphorylated Tm are driven by myosin with greater force than bare actin filaments. This result cannot be explained by simple steric hindrance and suggests that Tm may have additional effects on actin-myosin interactions. We therefore tested the hypothesis that Tm and its phosphorylation state affect the rate at which single actin-myosin bonds form and rupture. Using a laser trap, we measured the time necessary for the first bond to form between actin and rigor heavy meromyosin and the load-dependent durations of those bonds. Measurements were repeated in the presence of subsaturating myosin-S1 to force Tm from the closed to the open state. Maximum bond lifetimes increased in the open state, but only when Tm was phosphorylated. While the frequency with which bonds formed was extremely low in the closed state, when a bond did form it took significantly less time to do so than with bare actin. These data suggest there are at least two closed states of the thin filament, and that Tm provides additional points of contact for myosin.
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Affiliation(s)
- Vijay S Rao
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia 22908, USA
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17
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Bayeva M, Ardehali H. Mitochondrial dysfunction and oxidative damage to sarcomeric proteins. Curr Hypertens Rep 2011; 12:426-32. [PMID: 20865351 DOI: 10.1007/s11906-010-0149-8] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Hypertension is an important risk factor for the development of heart failure. Increased production of reactive oxygen species (ROS) contributes to cardiac dysfunction by activating numerous pro-hypertrophic signaling cascades and damaging the mitochondria, thus setting off a vicious cycle of ROS generation. The way in which oxidative stress leads to exacerbation of systolic and diastolic dysfunction is still unclear, however. In skeletal muscle and ischemic myocardium, increased ROS production causes preferential oxidation of myofibrillar proteins and provides a mechanistic link between oxidative damage and impaired contractility through disruption of actin-myosin interactions, enzymatic functions, calcium sensitivity, and efficiency of cross-bridge cycling. In this review, we summarize recent findings in the fields of heart failure and sarcomere biology and speculate that oxidative damage to myofibrils may contribute to the development of heart failure.
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Affiliation(s)
- Marina Bayeva
- Feinberg Cardiovascular Research Institute, Northwestern University, Feinberg School of Medicine, 303 East Chicago Avenue, Tarry 14-733, Chicago, IL 60611, USA.
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Abstract
Oxidative stress is common in many clinically important cardiac disorders, including ischemia/reperfusion, diabetes, and hypertensive heart disease. Oxidative stress leads to derangements in pump function due to changes in the expression or function of proteins that regulate intracellular Ca(2+) homeostasis. There is growing evidence that the cardiodepressant actions of reactive oxygen species (ROS) also are attributable to ROS-dependent signaling events in the sarcomere. This minireview focuses on myofilament protein post-translational modifications induced by ROS or ROS-activated signaling enzymes that regulate cardiac contractility.
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Affiliation(s)
- Marius P Sumandea
- Department of Physiology, Center for Muscle Biology, University of Kentucky, Lexington, Kentucky 40536, USA.
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19
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Liou YM, Hsieh SR, Wu TJ, Chen JY. Green tea extract given before regional myocardial ischemia-reperfusion in rats improves myocardial contractility by attenuating calcium overload. Pflugers Arch 2010; 460:1003-14. [PMID: 20922441 DOI: 10.1007/s00424-010-0881-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2010] [Revised: 09/06/2010] [Accepted: 09/09/2010] [Indexed: 01/03/2023]
Abstract
There is evidence for a negative correlation between green tea consumption and cardiovascular diseases. The aim of the present study was to examine whether green tea extract (GTE) given before regional myocardial ischemia could improve depression of myocardial contractility by preventing cytosolic Ca(2+) overload. Regional ischemia-reperfusion (IR) was induced in rats by ligating the left anterior descending branch for 20 min, then releasing the ligature. Ligation induced ventricular arrhythmias in rats without GTE pretreatment, but decreased arrhythmogenesis was seen in rats pretreated 30 min earlier with GTE (400 mg/kg). During reperfusion, arrhythmias only occurred during the initial 5 min, and GTE pretreatment had no effect. After overnight recovery, serum cTnI levels were greatly increased in control post-IR rats but only slightly elevated in GTE-pretreated post-IR rats. Myocardial contractility measured by echocardiography was still depressed after 3 days in control post-IR rats, but not in GTE-pretreated post-IR rats. No myocardial ischemic injury was seen in post-IR rats with or without GTE pretreatment. Using freshly isolated single heart myocytes, GTE was found to attenuate the post-IR injury-associated cytosolic Ca(2+) overload and modulate changes in the levels and distribution of myofibril, adherens junction, and gap junction proteins. In summary, GTE pretreatment protects cardiomyocytes from IR injury by preventing cytosolic Ca(2+) overload, myofibril disruption, and alterations in adherens and gap junction protein expression and distribution.
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Affiliation(s)
- Ying-Ming Liou
- Department of Life Sciences, National Chung-Hsing University, Taichung 402, Taiwan.
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Rao VS, Marongelli EN, Guilford WH. Phosphorylation of tropomyosin extends cooperative binding of myosin beyond a single regulatory unit. ACTA ACUST UNITED AC 2009; 66:10-23. [PMID: 18985725 DOI: 10.1002/cm.20321] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Tropomyosin (Tm) is one of the major phosphoproteins comprising the thin filament of muscle. However, the specific role of Tm phosphorylation in modulating the mechanics of actomyosin interaction has not been determined. Here we show that Tm phosphorylation is necessary for long-range cooperative activation of myosin binding. We used a novel optical trapping assay to measure the isometric stall force of an ensemble of myosin molecules moving actin filaments reconstituted with either natively phosphorylated or dephosphorylated Tm. The data show that the thin filament is cooperatively activated by myosin across regulatory units when Tm is phosphorylated. When Tm is dephosphorylated, this "long-range" cooperative activation is lost and the filament behaves identically to bare actin filaments. However, these effects are not due to dissociation of dephosphorylated Tm from the reconstituted thin filament. The data suggest that end-to-end interactions of adjacent Tm molecules are strengthened when Tm is phosphorylated, and that phosphorylation is thus essential for long range cooperative activation along the thin filament.
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Affiliation(s)
- Vijay S Rao
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA 22908, USA
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21
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Warren CM, Arteaga GM, Rajan S, Ahmed RPH, Wieczorek DF, Solaro RJ. Use of 2-D DIGE analysis reveals altered phosphorylation in a tropomyosin mutant (Glu54Lys) linked to dilated cardiomyopathy. Proteomics 2008; 8:100-5. [PMID: 18095372 DOI: 10.1002/pmic.200700772] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Current electrophoretic methods have not been optimized to fully separate post-translationally modified mutant forms of tropomyosin (Tm) from wild-type cardiac samples. We describe here a method employing a modified 2-D PAGE/2-D DIGE protocol, to fully separate native, mutant (E54K), and phosphorylated forms of Tm. Our data demonstrate the first evidence of a significant (approximately 40%) decrease in Tm phosphorylation in transgenic compared to non-transgenic mouse hearts, and indicate that altered phosphorylation may be a significant factor in the linkage of the E54K mutation to dilated cardiomyopathy.
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Affiliation(s)
- Chad M Warren
- Department of Physiology and Biophysics, Center for Cardiovascular Research, College of Medicine, University of Illinois at Chicago, 835 E. Wolcott Avenue, Chicago, IL 60612, USA
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Snook JH, Li J, Helmke BP, Guilford WH. Peroxynitrite inhibits myofibrillar protein function in an in vitro assay of motility. Free Radic Biol Med 2008; 44:14-23. [PMID: 18045543 PMCID: PMC2180163 DOI: 10.1016/j.freeradbiomed.2007.09.004] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/13/2007] [Revised: 08/30/2007] [Accepted: 09/04/2007] [Indexed: 12/17/2022]
Abstract
We determined the effects of peroxynitrite (ONOO-) on cardiac myosin, actin, and thin filaments in order to more clearly understand the impact of this reactive compound in ischemia/reperfusion injury and heart failure. Actin filaments, native thin filaments, and alpha-cardiac myosin from rat hearts were exposed to ONOO- in the presence of 2 mM bicarbonate. Filament velocities over myosin, calcium sensitivity, and relative force generated by myosin were assessed in an in vitro motility assay in the absence of reducing agents. ONOO- concentrations > or =10 microM significantly reduced the velocities of thin filaments or bare actin filaments over alpha-cardiac myosin when any of these proteins were exposed individually. These functional deficits were linearly related to the degree of tyrosine nitration, with myosin being the most sensitive. However, at 10 microM ONOO- the calcium sensitivity of thin filaments remained unchanged. Cotreatment of myosin and thin filaments, analogous to the in vivo situation, resulted in a significantly greater functional deficit. The load supported by myosin after ONOO- exposure was estimated using mixtures experiments to be increased threefold. These data suggest that nitration of myofibrillar proteins can contribute to cardiac contractile dysfunction in pathologic states in which ONOO- is liberated.
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