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Dias IHK, Shokr H. Oxysterols as Biomarkers of Aging and Disease. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2024; 1440:307-336. [PMID: 38036887 DOI: 10.1007/978-3-031-43883-7_16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/02/2023]
Abstract
Oxysterols derive from either enzymatic or non-enzymatic oxidation of cholesterol. Even though they are produced as intermediates of bile acid synthesis pathway, they are recognised as bioactive compounds in cellular processes. Therefore, their absence or accumulation have been shown to be associated with disease phenotypes. This chapter discusses the contribution of oxysterol to ageing, age-related diseases such as neurodegeneration and various disorders such as cancer, cardiovascular disease, diabetes, metabolic and ocular disorders. It is clear that oxysterols play a significant role in development and progression of these diseases. As a result, oxysterols are being investigated as suitable markers for disease diagnosis purposes and some drug targets are in development targeting oxysterol pathways. However, further research will be needed to confirm the suitability of these potentials.
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Affiliation(s)
- Irundika H K Dias
- Aston Medical School, College of Health and Life Sciences, Aston University, Birmingham, UK.
| | - Hala Shokr
- Manchester Pharmacy School, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK
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Usselman CW, Lindsey ML, Robinson AT, Habecker BA, Taylor CE, Merryman WD, Kimmerly D, Bender JR, Regensteiner JG, Moreau KL, Pilote L, Wenner MM, O'Brien M, Yarovinsky TO, Stachenfeld NS, Charkoudian N, Denfeld QE, Moreira-Bouchard JD, Pyle WG, DeLeon-Pennell KY. Guidelines on the use of sex and gender in cardiovascular research. Am J Physiol Heart Circ Physiol 2024; 326:H238-H255. [PMID: 37999647 DOI: 10.1152/ajpheart.00535.2023] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 11/02/2023] [Accepted: 11/21/2023] [Indexed: 11/25/2023]
Abstract
In cardiovascular research, sex and gender have not typically been considered in research design and reporting until recently. This has resulted in clinical research findings from which not only all women, but also gender-diverse individuals have been excluded. The resulting dearth of data has led to a lack of sex- and gender-specific clinical guidelines and raises serious questions about evidence-based care. Basic research has also excluded considerations of sex. Including sex and/or gender as research variables not only has the potential to improve the health of society overall now, but it also provides a foundation of knowledge on which to build future advances. The goal of this guidelines article is to provide advice on best practices to include sex and gender considerations in study design, as well as data collection, analysis, and interpretation to optimally establish rigor and reproducibility needed to inform clinical decision-making and improve outcomes. In cardiovascular physiology, incorporating sex and gender is a necessary component when optimally designing and executing research plans. The guidelines serve as the first guidance on how to include sex and gender in cardiovascular research. We provide here a beginning path toward achieving this goal and improve the ability of the research community to interpret results through a sex and gender lens to enable comparison across studies and laboratories, resulting in better health for all.
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Affiliation(s)
- Charlotte W Usselman
- Cardiovascular Health and Autonomic Regulation Laboratory, Department of Kinesiology and Physical Education, McGill University, Montreal, Quebec, Canada
| | - Merry L Lindsey
- School of Graduate Studies, Meharry Medical College, Nashville, Tennessee, United States
- Research Service, Nashville Veterans Affairs Medical Center, Nashville, Tennessee, United States
| | - Austin T Robinson
- Neurovascular Physiology Laboratory, School of Kinesiology, Auburn University, Auburn, Alabama, United States
| | - Beth A Habecker
- Department of Chemical Physiology and Biochemistry and Knight Cardiovascular Institute, Oregon Health and Science University, Portland, Oregon, United States
| | - Chloe E Taylor
- School of Health Sciences, Western Sydney University, Sydney, New South Wales, Australia
| | - W David Merryman
- Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee, United States
| | - Derek Kimmerly
- Autonomic Cardiovascular Control and Exercise Laboratory, Division of Kinesiology, School of Health and Human Performance, Faculty of Health, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Jeffrey R Bender
- Section of Cardiovascular Medicine, Department of Internal Medicine, Yale Cardiovascular Research Center, New Haven, Connecticut, United States
- Department of Immunobiology, Yale University School of Medicine, New Haven, Connecticut, United States
| | - Judith G Regensteiner
- Divisions of General Internal Medicine and Cardiology, Department of Medicine, Ludeman Family Center for Women's Health Research, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
| | - Kerrie L Moreau
- Division of Geriatrics, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
- Eastern Colorado Health Care System, Geriatric Research Education and Clinical Center, Aurora, Colorado, United States
| | - Louise Pilote
- Centre for Outcomes Research and Evaluation, Research Institute of the McGill University Health Centre, McGill University, Montreal, Quebec, Canada
| | - Megan M Wenner
- Department of Kinesiology and Applied Physiology, University of Delaware, Newark, Delaware, United States
| | - Myles O'Brien
- School of Physiotherapy and Department of Medicine, Faculty of Health, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Timur O Yarovinsky
- Section of Cardiovascular Medicine, Department of Internal Medicine, Yale Cardiovascular Research Center, New Haven, Connecticut, United States
- Department of Immunobiology, Yale University School of Medicine, New Haven, Connecticut, United States
| | - Nina S Stachenfeld
- John B. Pierce Laboratory, New Haven, Connecticut, United States
- Department of Obstetrics, Gynecology and Reproductive Sciences, Yale School of Medicine, New Haven, Connecticut, United States
| | - Nisha Charkoudian
- Thermal and Mountain Medicine Division, United States Army Research Institute of Environmental Medicine, Natick, Massachusetts, United States
| | - Quin E Denfeld
- School of Nursing and Knight Cardiovascular Institute, Oregon Health and Science University, Portland, Oregon, United States
| | - Jesse D Moreira-Bouchard
- Q.U.E.E.R. Lab, Programs in Human Physiology, Department of Health Sciences, Boston University College of Health and Rehabilitation Sciences: Sargent College, Boston, Massachusetts, United States
| | - W Glen Pyle
- IMPART Team Canada Network, Dalhousie Medicine, Saint John, New Brunswick, Canada
- Department of Biomedical Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Kristine Y DeLeon-Pennell
- School of Medicine, Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, South Carolina, United States
- Research Service, Ralph H. Johnson Veterans Affairs Medical Center, Charleston, South Carolina, United States
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Arici M, Ferrandi M, Barassi P, Hsu SC, Torre E, Luraghi A, Ronchi C, Chang GJ, Peri F, Ferrari P, Bianchi G, Rocchetti M, Zaza A. Istaroxime Metabolite PST3093 Selectively Stimulates SERCA2a and Reverses Disease-Induced Changes in Cardiac Function. J Pharmacol Exp Ther 2023; 384:231-244. [PMID: 36153005 DOI: 10.1124/jpet.122.001335] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 07/11/2022] [Accepted: 08/01/2022] [Indexed: 01/03/2023] Open
Abstract
Heart failure (HF) therapeutic toolkit would strongly benefit from the availability of ino-lusitropic agents with a favorable pharmacodynamics and safety profile. Istaroxime is a promising agent, which combines Na+/K+ pump inhibition with sarcoplasmic reticulum Ca2+ ATPase (SERCA2a) stimulation; however, it has a very short half-life and extensive metabolism to a molecule named PST3093. The present work aims to investigate whether PST3093 still retains the pharmacodynamic and pharmacokinetic properties of its parent compound. We studied PST3093 for its effects on SERCA2a and Na+/K+ ATPase activities, Ca2+ dynamics in isolated myocytes, and hemodynamic effects in an in vivo rat model of diabetic [streptozotocin (STZ)-induced] cardiomyopathy. Istaroxime infusion in HF patients led to accumulation of PST3093 in the plasma; clearance was substantially slower for PST3093 than for istaroxime. In cardiac rat preparations, PST3093 did not inhibit the Na+/K+ ATPase activity but retained SERCA2a stimulatory activity. In in vivo echocardiographic assessment, PST3093 improved overall cardiac performance and reversed most STZ-induced abnormalities. PST3093 intravenous toxicity was considerably lower than that of istaroxime, and it failed to significantly interact with 50 off-targets. Overall, PST3093 is a "selective" SERCA2a activator, the prototype of a novel pharmacodynamic category with a potential in the ino-lusitropic approach to HF with prevailing diastolic dysfunction. Its pharmacodynamics are peculiar, and its pharmacokinetics are suitable to prolong the cardiac beneficial effect of istaroxime infusion. SIGNIFICANCE STATEMENT: Heart failure (HF) treatment would benefit from the availability of ino-lusitropic agents with favourable profiles. PST3093 is the main metabolite of istaroxime, a promising agent combining Na+/K+ pump inhibition and sarcoplasmic reticulum Ca2+ ATPase2a (SERCA2a) stimulation. PST3093 shows a longer half-life in human circulation compared to istaroxime, selectively activates SERCA2a, and improves cardiac performance in a model of diabetic cardiomyopathy. Overall, PST3093 as a selective SERCA2a activator can be considered the prototype of a novel pharmacodynamic category for HF treatment.
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Affiliation(s)
- Martina Arici
- Department of Biotechnology and Biosciences, Università degli Studi di Milano-Bicocca, Milan, Italy (M.A., E.T., A.L., C.R., F.P., M.R., A.Z.); Windtree Therapeutics Inc., Warrington, Pennsylvania (M.F., P.B., P.F., G.B.); CVie Therapeutics Limited, Taipei, Taiwan (S.-C.H.); Graduate Institute of Clinical Medicinal Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan (G.-J.C.); and Università Vita-Salute San Raffaele, Milan, Italy (G.B.)
| | - Mara Ferrandi
- Department of Biotechnology and Biosciences, Università degli Studi di Milano-Bicocca, Milan, Italy (M.A., E.T., A.L., C.R., F.P., M.R., A.Z.); Windtree Therapeutics Inc., Warrington, Pennsylvania (M.F., P.B., P.F., G.B.); CVie Therapeutics Limited, Taipei, Taiwan (S.-C.H.); Graduate Institute of Clinical Medicinal Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan (G.-J.C.); and Università Vita-Salute San Raffaele, Milan, Italy (G.B.)
| | - Paolo Barassi
- Department of Biotechnology and Biosciences, Università degli Studi di Milano-Bicocca, Milan, Italy (M.A., E.T., A.L., C.R., F.P., M.R., A.Z.); Windtree Therapeutics Inc., Warrington, Pennsylvania (M.F., P.B., P.F., G.B.); CVie Therapeutics Limited, Taipei, Taiwan (S.-C.H.); Graduate Institute of Clinical Medicinal Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan (G.-J.C.); and Università Vita-Salute San Raffaele, Milan, Italy (G.B.)
| | - Shih-Che Hsu
- Department of Biotechnology and Biosciences, Università degli Studi di Milano-Bicocca, Milan, Italy (M.A., E.T., A.L., C.R., F.P., M.R., A.Z.); Windtree Therapeutics Inc., Warrington, Pennsylvania (M.F., P.B., P.F., G.B.); CVie Therapeutics Limited, Taipei, Taiwan (S.-C.H.); Graduate Institute of Clinical Medicinal Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan (G.-J.C.); and Università Vita-Salute San Raffaele, Milan, Italy (G.B.)
| | - Eleonora Torre
- Department of Biotechnology and Biosciences, Università degli Studi di Milano-Bicocca, Milan, Italy (M.A., E.T., A.L., C.R., F.P., M.R., A.Z.); Windtree Therapeutics Inc., Warrington, Pennsylvania (M.F., P.B., P.F., G.B.); CVie Therapeutics Limited, Taipei, Taiwan (S.-C.H.); Graduate Institute of Clinical Medicinal Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan (G.-J.C.); and Università Vita-Salute San Raffaele, Milan, Italy (G.B.)
| | - Andrea Luraghi
- Department of Biotechnology and Biosciences, Università degli Studi di Milano-Bicocca, Milan, Italy (M.A., E.T., A.L., C.R., F.P., M.R., A.Z.); Windtree Therapeutics Inc., Warrington, Pennsylvania (M.F., P.B., P.F., G.B.); CVie Therapeutics Limited, Taipei, Taiwan (S.-C.H.); Graduate Institute of Clinical Medicinal Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan (G.-J.C.); and Università Vita-Salute San Raffaele, Milan, Italy (G.B.)
| | - Carlotta Ronchi
- Department of Biotechnology and Biosciences, Università degli Studi di Milano-Bicocca, Milan, Italy (M.A., E.T., A.L., C.R., F.P., M.R., A.Z.); Windtree Therapeutics Inc., Warrington, Pennsylvania (M.F., P.B., P.F., G.B.); CVie Therapeutics Limited, Taipei, Taiwan (S.-C.H.); Graduate Institute of Clinical Medicinal Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan (G.-J.C.); and Università Vita-Salute San Raffaele, Milan, Italy (G.B.)
| | - Gwo-Jyh Chang
- Department of Biotechnology and Biosciences, Università degli Studi di Milano-Bicocca, Milan, Italy (M.A., E.T., A.L., C.R., F.P., M.R., A.Z.); Windtree Therapeutics Inc., Warrington, Pennsylvania (M.F., P.B., P.F., G.B.); CVie Therapeutics Limited, Taipei, Taiwan (S.-C.H.); Graduate Institute of Clinical Medicinal Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan (G.-J.C.); and Università Vita-Salute San Raffaele, Milan, Italy (G.B.)
| | - Francesco Peri
- Department of Biotechnology and Biosciences, Università degli Studi di Milano-Bicocca, Milan, Italy (M.A., E.T., A.L., C.R., F.P., M.R., A.Z.); Windtree Therapeutics Inc., Warrington, Pennsylvania (M.F., P.B., P.F., G.B.); CVie Therapeutics Limited, Taipei, Taiwan (S.-C.H.); Graduate Institute of Clinical Medicinal Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan (G.-J.C.); and Università Vita-Salute San Raffaele, Milan, Italy (G.B.)
| | - Patrizia Ferrari
- Department of Biotechnology and Biosciences, Università degli Studi di Milano-Bicocca, Milan, Italy (M.A., E.T., A.L., C.R., F.P., M.R., A.Z.); Windtree Therapeutics Inc., Warrington, Pennsylvania (M.F., P.B., P.F., G.B.); CVie Therapeutics Limited, Taipei, Taiwan (S.-C.H.); Graduate Institute of Clinical Medicinal Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan (G.-J.C.); and Università Vita-Salute San Raffaele, Milan, Italy (G.B.)
| | - Giuseppe Bianchi
- Department of Biotechnology and Biosciences, Università degli Studi di Milano-Bicocca, Milan, Italy (M.A., E.T., A.L., C.R., F.P., M.R., A.Z.); Windtree Therapeutics Inc., Warrington, Pennsylvania (M.F., P.B., P.F., G.B.); CVie Therapeutics Limited, Taipei, Taiwan (S.-C.H.); Graduate Institute of Clinical Medicinal Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan (G.-J.C.); and Università Vita-Salute San Raffaele, Milan, Italy (G.B.)
| | - Marcella Rocchetti
- Department of Biotechnology and Biosciences, Università degli Studi di Milano-Bicocca, Milan, Italy (M.A., E.T., A.L., C.R., F.P., M.R., A.Z.); Windtree Therapeutics Inc., Warrington, Pennsylvania (M.F., P.B., P.F., G.B.); CVie Therapeutics Limited, Taipei, Taiwan (S.-C.H.); Graduate Institute of Clinical Medicinal Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan (G.-J.C.); and Università Vita-Salute San Raffaele, Milan, Italy (G.B.)
| | - Antonio Zaza
- Department of Biotechnology and Biosciences, Università degli Studi di Milano-Bicocca, Milan, Italy (M.A., E.T., A.L., C.R., F.P., M.R., A.Z.); Windtree Therapeutics Inc., Warrington, Pennsylvania (M.F., P.B., P.F., G.B.); CVie Therapeutics Limited, Taipei, Taiwan (S.-C.H.); Graduate Institute of Clinical Medicinal Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan (G.-J.C.); and Università Vita-Salute San Raffaele, Milan, Italy (G.B.)
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Badone B, Ronchi C, Lodola F, Knaust AE, Hansen A, Eschenhagen T, Zaza A. Characterization of the PLN p.Arg14del Mutation in Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes. Int J Mol Sci 2021; 22:13500. [PMID: 34948294 PMCID: PMC8709382 DOI: 10.3390/ijms222413500] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 12/10/2021] [Accepted: 12/12/2021] [Indexed: 01/19/2023] Open
Abstract
Phospholamban (PLN) is the natural inhibitor of the sarco/endoplasmic reticulum Ca2+ ATP-ase (SERCA2a). Heterozygous PLN p.Arg14del mutation is associated with an arrhythmogenic dilated cardiomyopathy (DCM), whose pathogenesis has been attributed to SERCA2a "superinhibition". AIM To test in cardiomyocytes (hiPSC-CMs) derived from a PLN p.Arg14del carrier whether (1) Ca2+ dynamics and protein localization were compatible with SERCA2a superinhibition and (2) if functional abnormalities could be reverted by pharmacological SERCA2a activation (PST3093). METHODS Ca2+ transients (CaT) were recorded at 36 °C in hiPSC-CMs clusters during field stimulation. SERCA2a and PLN where immunolabeled in single hiPSC-CMs. Mutant preparations (MUT) were compared to isogenic wild-type ones (WT), obtained by mutation reversal. RESULTS WT and MUT differed for the following properties: (1) CaT time to peak (tpeak) and half-time of CaT decay were shorter in MUT; (2) several CaT profiles were identified in WT, "hyperdynamic" ones largely prevailed in MUT; (3) whereas tpeak rate-dependently declined in WT, it was shorter and rate-independent in MUT; (4) diastolic Ca2+ rate-dependently accumulated in WT, but not in MUT. When applied to WT, PST3093 turned all the above properties to resemble those of MUT; when applied to MUT, PST3093 had a smaller or negligible effect. Preferential perinuclear SERCA2a-PLN localization was lost in MUT hiPSC-CMs. CONCLUSIONS Functional data converge to argue for PLN p.Arg14del incompetence in inhibiting SERCA2a in the tested case, thus weakening the rationale for therapeutic SERCA2a activation. Mechanisms alternative to SERCA2a superinhibition should be considered in the pathogenesis of DCM, possibly including dysregulation of Ca2+-dependent transcription.
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Affiliation(s)
- Beatrice Badone
- Laboratory of Cardiac Cellular Physiology, Department of Biotechnology and Bioscience, University of Milano-Bicocca, 20126 Milan, Italy; (B.B.); (C.R.); (F.L.)
| | - Carlotta Ronchi
- Laboratory of Cardiac Cellular Physiology, Department of Biotechnology and Bioscience, University of Milano-Bicocca, 20126 Milan, Italy; (B.B.); (C.R.); (F.L.)
| | - Francesco Lodola
- Laboratory of Cardiac Cellular Physiology, Department of Biotechnology and Bioscience, University of Milano-Bicocca, 20126 Milan, Italy; (B.B.); (C.R.); (F.L.)
| | - Anika E. Knaust
- Department of Experimental Pharmacology and Toxicology, Cardiovascular Research Center, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; (A.E.K.); (A.H.); (T.E.)
- German Centre for Cardiovascular Research (DZHK), Partner Site Hamburg/Kiel/Lübeck, 20249 Hamburg, Germany
| | - Arne Hansen
- Department of Experimental Pharmacology and Toxicology, Cardiovascular Research Center, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; (A.E.K.); (A.H.); (T.E.)
- German Centre for Cardiovascular Research (DZHK), Partner Site Hamburg/Kiel/Lübeck, 20249 Hamburg, Germany
| | - Thomas Eschenhagen
- Department of Experimental Pharmacology and Toxicology, Cardiovascular Research Center, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; (A.E.K.); (A.H.); (T.E.)
- German Centre for Cardiovascular Research (DZHK), Partner Site Hamburg/Kiel/Lübeck, 20249 Hamburg, Germany
| | - Antonio Zaza
- Laboratory of Cardiac Cellular Physiology, Department of Biotechnology and Bioscience, University of Milano-Bicocca, 20126 Milan, Italy; (B.B.); (C.R.); (F.L.)
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Mollanoori H, Naderi N, Amin A, Hassani B, Shahraki H, Teimourian S. A novel human T17N-phospholamban variation in idiopathic dilated cardiomyopathy. GENE REPORTS 2018. [DOI: 10.1016/j.genrep.2018.06.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Zhang B, Novitskaya T, Wheeler DG, Xu Z, Chepurko E, Huttinger R, He H, Varadharaj S, Zweier JL, Song Y, Xu M, Harrell FE, Su YR, Absi T, Kohr MJ, Ziolo MT, Roden DM, Shaffer CM, Galindo CL, Wells QS, Gumina RJ. Kcnj11 Ablation Is Associated With Increased Nitro-Oxidative Stress During Ischemia-Reperfusion Injury: Implications for Human Ischemic Cardiomyopathy. Circ Heart Fail 2017; 10:CIRCHEARTFAILURE.116.003523. [PMID: 28209764 DOI: 10.1161/circheartfailure.116.003523] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Accepted: 01/06/2017] [Indexed: 11/16/2022]
Abstract
BACKGROUND Despite increased secondary cardiovascular events in patients with ischemic cardiomyopathy (ICM), the expression of innate cardiac protective molecules in the hearts of patients with ICM is incompletely characterized. Therefore, we used a nonbiased RNAseq approach to determine whether differences in cardiac protective molecules occur with ICM. METHODS AND RESULTS RNAseq analysis of human control and ICM left ventricular samples demonstrated a significant decrease in KCNJ11 expression with ICM. KCNJ11 encodes the Kir6.2 subunit of the cardioprotective KATP channel. Using wild-type mice and kcnj11-deficient (kcnj11-null) mice, we examined the effect of kcnj11 expression on cardiac function during ischemia-reperfusion injury. Reactive oxygen species generation increased in kcnj11-null hearts above that found in wild-type mice hearts after ischemia-reperfusion injury. Continuous left ventricular pressure measurement during ischemia and reperfusion demonstrated a more compromised diastolic function in kcnj11-null compared with wild-type mice during reperfusion. Analysis of key calcium-regulating proteins revealed significant differences in kcnj11-null mice. Despite impaired relaxation, kcnj11-null hearts increased phospholamban Ser16 phosphorylation, a modification that results in the dissociation of phospholamban from sarcoendoplasmic reticulum Ca2+, thereby increasing sarcoendoplasmic reticulum Ca2+-mediated calcium reuptake. However, kcnj11-null mice also had increased 3-nitrotyrosine modification of the sarcoendoplasmic reticulum Ca2+-ATPase, a modification that irreversibly impairs sarcoendoplasmic reticulum Ca2+ function, thereby contributing to diastolic dysfunction. CONCLUSIONS KCNJ11 expression is decreased in human ICM. Lack of kcnj11 expression increases peroxynitrite-mediated modification of the key calcium-handling protein sarcoendoplasmic reticulum Ca2+-ATPase after myocardial ischemia-reperfusion injury, contributing to impaired diastolic function. These data suggest a mechanism for ischemia-induced diastolic dysfunction in patients with ICM.
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Affiliation(s)
- Bo Zhang
- From the Division of Cardiovascular Medicine, Davis Heart and Lung Research Institute (B.Z., D.G.W., Z.X., R.H., H.H., S.V., J.L.Z.), Department of Physiology and Cell Biology (B.Z., J.L.Z., M.J.K., M.T.Z.), The Ohio State University, Columbus; Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, HuBei, China (B.Z.); Department of Biostatistics (Y.S., M.X., F.E.H.), Division of Clinical Pharmacology, Department of Medicine (D.M.R., C.M.S.), Division of Cardiac Surgery, Department of Surgery (T.A.), Division of Cardiovascular Medicine (T. N., E. C., Y.R.S., D.R., C.L.G., Q.S.W, R.J.G.), Department of Pharmacology and Department of Pathology, Immunology, and Microbiology (R.J.G.), Vanderbilt University Medical Center, Nashville, TN
| | - Tatiana Novitskaya
- From the Division of Cardiovascular Medicine, Davis Heart and Lung Research Institute (B.Z., D.G.W., Z.X., R.H., H.H., S.V., J.L.Z.), Department of Physiology and Cell Biology (B.Z., J.L.Z., M.J.K., M.T.Z.), The Ohio State University, Columbus; Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, HuBei, China (B.Z.); Department of Biostatistics (Y.S., M.X., F.E.H.), Division of Clinical Pharmacology, Department of Medicine (D.M.R., C.M.S.), Division of Cardiac Surgery, Department of Surgery (T.A.), Division of Cardiovascular Medicine (T. N., E. C., Y.R.S., D.R., C.L.G., Q.S.W, R.J.G.), Department of Pharmacology and Department of Pathology, Immunology, and Microbiology (R.J.G.), Vanderbilt University Medical Center, Nashville, TN
| | - Debra G Wheeler
- From the Division of Cardiovascular Medicine, Davis Heart and Lung Research Institute (B.Z., D.G.W., Z.X., R.H., H.H., S.V., J.L.Z.), Department of Physiology and Cell Biology (B.Z., J.L.Z., M.J.K., M.T.Z.), The Ohio State University, Columbus; Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, HuBei, China (B.Z.); Department of Biostatistics (Y.S., M.X., F.E.H.), Division of Clinical Pharmacology, Department of Medicine (D.M.R., C.M.S.), Division of Cardiac Surgery, Department of Surgery (T.A.), Division of Cardiovascular Medicine (T. N., E. C., Y.R.S., D.R., C.L.G., Q.S.W, R.J.G.), Department of Pharmacology and Department of Pathology, Immunology, and Microbiology (R.J.G.), Vanderbilt University Medical Center, Nashville, TN
| | - Zhaobin Xu
- From the Division of Cardiovascular Medicine, Davis Heart and Lung Research Institute (B.Z., D.G.W., Z.X., R.H., H.H., S.V., J.L.Z.), Department of Physiology and Cell Biology (B.Z., J.L.Z., M.J.K., M.T.Z.), The Ohio State University, Columbus; Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, HuBei, China (B.Z.); Department of Biostatistics (Y.S., M.X., F.E.H.), Division of Clinical Pharmacology, Department of Medicine (D.M.R., C.M.S.), Division of Cardiac Surgery, Department of Surgery (T.A.), Division of Cardiovascular Medicine (T. N., E. C., Y.R.S., D.R., C.L.G., Q.S.W, R.J.G.), Department of Pharmacology and Department of Pathology, Immunology, and Microbiology (R.J.G.), Vanderbilt University Medical Center, Nashville, TN
| | - Elena Chepurko
- From the Division of Cardiovascular Medicine, Davis Heart and Lung Research Institute (B.Z., D.G.W., Z.X., R.H., H.H., S.V., J.L.Z.), Department of Physiology and Cell Biology (B.Z., J.L.Z., M.J.K., M.T.Z.), The Ohio State University, Columbus; Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, HuBei, China (B.Z.); Department of Biostatistics (Y.S., M.X., F.E.H.), Division of Clinical Pharmacology, Department of Medicine (D.M.R., C.M.S.), Division of Cardiac Surgery, Department of Surgery (T.A.), Division of Cardiovascular Medicine (T. N., E. C., Y.R.S., D.R., C.L.G., Q.S.W, R.J.G.), Department of Pharmacology and Department of Pathology, Immunology, and Microbiology (R.J.G.), Vanderbilt University Medical Center, Nashville, TN
| | - Ryan Huttinger
- From the Division of Cardiovascular Medicine, Davis Heart and Lung Research Institute (B.Z., D.G.W., Z.X., R.H., H.H., S.V., J.L.Z.), Department of Physiology and Cell Biology (B.Z., J.L.Z., M.J.K., M.T.Z.), The Ohio State University, Columbus; Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, HuBei, China (B.Z.); Department of Biostatistics (Y.S., M.X., F.E.H.), Division of Clinical Pharmacology, Department of Medicine (D.M.R., C.M.S.), Division of Cardiac Surgery, Department of Surgery (T.A.), Division of Cardiovascular Medicine (T. N., E. C., Y.R.S., D.R., C.L.G., Q.S.W, R.J.G.), Department of Pharmacology and Department of Pathology, Immunology, and Microbiology (R.J.G.), Vanderbilt University Medical Center, Nashville, TN
| | - Heng He
- From the Division of Cardiovascular Medicine, Davis Heart and Lung Research Institute (B.Z., D.G.W., Z.X., R.H., H.H., S.V., J.L.Z.), Department of Physiology and Cell Biology (B.Z., J.L.Z., M.J.K., M.T.Z.), The Ohio State University, Columbus; Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, HuBei, China (B.Z.); Department of Biostatistics (Y.S., M.X., F.E.H.), Division of Clinical Pharmacology, Department of Medicine (D.M.R., C.M.S.), Division of Cardiac Surgery, Department of Surgery (T.A.), Division of Cardiovascular Medicine (T. N., E. C., Y.R.S., D.R., C.L.G., Q.S.W, R.J.G.), Department of Pharmacology and Department of Pathology, Immunology, and Microbiology (R.J.G.), Vanderbilt University Medical Center, Nashville, TN
| | - Saradhadevi Varadharaj
- From the Division of Cardiovascular Medicine, Davis Heart and Lung Research Institute (B.Z., D.G.W., Z.X., R.H., H.H., S.V., J.L.Z.), Department of Physiology and Cell Biology (B.Z., J.L.Z., M.J.K., M.T.Z.), The Ohio State University, Columbus; Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, HuBei, China (B.Z.); Department of Biostatistics (Y.S., M.X., F.E.H.), Division of Clinical Pharmacology, Department of Medicine (D.M.R., C.M.S.), Division of Cardiac Surgery, Department of Surgery (T.A.), Division of Cardiovascular Medicine (T. N., E. C., Y.R.S., D.R., C.L.G., Q.S.W, R.J.G.), Department of Pharmacology and Department of Pathology, Immunology, and Microbiology (R.J.G.), Vanderbilt University Medical Center, Nashville, TN
| | - Jay L Zweier
- From the Division of Cardiovascular Medicine, Davis Heart and Lung Research Institute (B.Z., D.G.W., Z.X., R.H., H.H., S.V., J.L.Z.), Department of Physiology and Cell Biology (B.Z., J.L.Z., M.J.K., M.T.Z.), The Ohio State University, Columbus; Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, HuBei, China (B.Z.); Department of Biostatistics (Y.S., M.X., F.E.H.), Division of Clinical Pharmacology, Department of Medicine (D.M.R., C.M.S.), Division of Cardiac Surgery, Department of Surgery (T.A.), Division of Cardiovascular Medicine (T. N., E. C., Y.R.S., D.R., C.L.G., Q.S.W, R.J.G.), Department of Pharmacology and Department of Pathology, Immunology, and Microbiology (R.J.G.), Vanderbilt University Medical Center, Nashville, TN
| | - Yanna Song
- From the Division of Cardiovascular Medicine, Davis Heart and Lung Research Institute (B.Z., D.G.W., Z.X., R.H., H.H., S.V., J.L.Z.), Department of Physiology and Cell Biology (B.Z., J.L.Z., M.J.K., M.T.Z.), The Ohio State University, Columbus; Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, HuBei, China (B.Z.); Department of Biostatistics (Y.S., M.X., F.E.H.), Division of Clinical Pharmacology, Department of Medicine (D.M.R., C.M.S.), Division of Cardiac Surgery, Department of Surgery (T.A.), Division of Cardiovascular Medicine (T. N., E. C., Y.R.S., D.R., C.L.G., Q.S.W, R.J.G.), Department of Pharmacology and Department of Pathology, Immunology, and Microbiology (R.J.G.), Vanderbilt University Medical Center, Nashville, TN
| | - Meng Xu
- From the Division of Cardiovascular Medicine, Davis Heart and Lung Research Institute (B.Z., D.G.W., Z.X., R.H., H.H., S.V., J.L.Z.), Department of Physiology and Cell Biology (B.Z., J.L.Z., M.J.K., M.T.Z.), The Ohio State University, Columbus; Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, HuBei, China (B.Z.); Department of Biostatistics (Y.S., M.X., F.E.H.), Division of Clinical Pharmacology, Department of Medicine (D.M.R., C.M.S.), Division of Cardiac Surgery, Department of Surgery (T.A.), Division of Cardiovascular Medicine (T. N., E. C., Y.R.S., D.R., C.L.G., Q.S.W, R.J.G.), Department of Pharmacology and Department of Pathology, Immunology, and Microbiology (R.J.G.), Vanderbilt University Medical Center, Nashville, TN
| | - Frank E Harrell
- From the Division of Cardiovascular Medicine, Davis Heart and Lung Research Institute (B.Z., D.G.W., Z.X., R.H., H.H., S.V., J.L.Z.), Department of Physiology and Cell Biology (B.Z., J.L.Z., M.J.K., M.T.Z.), The Ohio State University, Columbus; Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, HuBei, China (B.Z.); Department of Biostatistics (Y.S., M.X., F.E.H.), Division of Clinical Pharmacology, Department of Medicine (D.M.R., C.M.S.), Division of Cardiac Surgery, Department of Surgery (T.A.), Division of Cardiovascular Medicine (T. N., E. C., Y.R.S., D.R., C.L.G., Q.S.W, R.J.G.), Department of Pharmacology and Department of Pathology, Immunology, and Microbiology (R.J.G.), Vanderbilt University Medical Center, Nashville, TN
| | - Yan Ru Su
- From the Division of Cardiovascular Medicine, Davis Heart and Lung Research Institute (B.Z., D.G.W., Z.X., R.H., H.H., S.V., J.L.Z.), Department of Physiology and Cell Biology (B.Z., J.L.Z., M.J.K., M.T.Z.), The Ohio State University, Columbus; Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, HuBei, China (B.Z.); Department of Biostatistics (Y.S., M.X., F.E.H.), Division of Clinical Pharmacology, Department of Medicine (D.M.R., C.M.S.), Division of Cardiac Surgery, Department of Surgery (T.A.), Division of Cardiovascular Medicine (T. N., E. C., Y.R.S., D.R., C.L.G., Q.S.W, R.J.G.), Department of Pharmacology and Department of Pathology, Immunology, and Microbiology (R.J.G.), Vanderbilt University Medical Center, Nashville, TN
| | - Tarek Absi
- From the Division of Cardiovascular Medicine, Davis Heart and Lung Research Institute (B.Z., D.G.W., Z.X., R.H., H.H., S.V., J.L.Z.), Department of Physiology and Cell Biology (B.Z., J.L.Z., M.J.K., M.T.Z.), The Ohio State University, Columbus; Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, HuBei, China (B.Z.); Department of Biostatistics (Y.S., M.X., F.E.H.), Division of Clinical Pharmacology, Department of Medicine (D.M.R., C.M.S.), Division of Cardiac Surgery, Department of Surgery (T.A.), Division of Cardiovascular Medicine (T. N., E. C., Y.R.S., D.R., C.L.G., Q.S.W, R.J.G.), Department of Pharmacology and Department of Pathology, Immunology, and Microbiology (R.J.G.), Vanderbilt University Medical Center, Nashville, TN
| | - Mark J Kohr
- From the Division of Cardiovascular Medicine, Davis Heart and Lung Research Institute (B.Z., D.G.W., Z.X., R.H., H.H., S.V., J.L.Z.), Department of Physiology and Cell Biology (B.Z., J.L.Z., M.J.K., M.T.Z.), The Ohio State University, Columbus; Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, HuBei, China (B.Z.); Department of Biostatistics (Y.S., M.X., F.E.H.), Division of Clinical Pharmacology, Department of Medicine (D.M.R., C.M.S.), Division of Cardiac Surgery, Department of Surgery (T.A.), Division of Cardiovascular Medicine (T. N., E. C., Y.R.S., D.R., C.L.G., Q.S.W, R.J.G.), Department of Pharmacology and Department of Pathology, Immunology, and Microbiology (R.J.G.), Vanderbilt University Medical Center, Nashville, TN
| | - Mark T Ziolo
- From the Division of Cardiovascular Medicine, Davis Heart and Lung Research Institute (B.Z., D.G.W., Z.X., R.H., H.H., S.V., J.L.Z.), Department of Physiology and Cell Biology (B.Z., J.L.Z., M.J.K., M.T.Z.), The Ohio State University, Columbus; Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, HuBei, China (B.Z.); Department of Biostatistics (Y.S., M.X., F.E.H.), Division of Clinical Pharmacology, Department of Medicine (D.M.R., C.M.S.), Division of Cardiac Surgery, Department of Surgery (T.A.), Division of Cardiovascular Medicine (T. N., E. C., Y.R.S., D.R., C.L.G., Q.S.W, R.J.G.), Department of Pharmacology and Department of Pathology, Immunology, and Microbiology (R.J.G.), Vanderbilt University Medical Center, Nashville, TN
| | - Dan M Roden
- From the Division of Cardiovascular Medicine, Davis Heart and Lung Research Institute (B.Z., D.G.W., Z.X., R.H., H.H., S.V., J.L.Z.), Department of Physiology and Cell Biology (B.Z., J.L.Z., M.J.K., M.T.Z.), The Ohio State University, Columbus; Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, HuBei, China (B.Z.); Department of Biostatistics (Y.S., M.X., F.E.H.), Division of Clinical Pharmacology, Department of Medicine (D.M.R., C.M.S.), Division of Cardiac Surgery, Department of Surgery (T.A.), Division of Cardiovascular Medicine (T. N., E. C., Y.R.S., D.R., C.L.G., Q.S.W, R.J.G.), Department of Pharmacology and Department of Pathology, Immunology, and Microbiology (R.J.G.), Vanderbilt University Medical Center, Nashville, TN
| | - Christian M Shaffer
- From the Division of Cardiovascular Medicine, Davis Heart and Lung Research Institute (B.Z., D.G.W., Z.X., R.H., H.H., S.V., J.L.Z.), Department of Physiology and Cell Biology (B.Z., J.L.Z., M.J.K., M.T.Z.), The Ohio State University, Columbus; Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, HuBei, China (B.Z.); Department of Biostatistics (Y.S., M.X., F.E.H.), Division of Clinical Pharmacology, Department of Medicine (D.M.R., C.M.S.), Division of Cardiac Surgery, Department of Surgery (T.A.), Division of Cardiovascular Medicine (T. N., E. C., Y.R.S., D.R., C.L.G., Q.S.W, R.J.G.), Department of Pharmacology and Department of Pathology, Immunology, and Microbiology (R.J.G.), Vanderbilt University Medical Center, Nashville, TN
| | - Cristi L Galindo
- From the Division of Cardiovascular Medicine, Davis Heart and Lung Research Institute (B.Z., D.G.W., Z.X., R.H., H.H., S.V., J.L.Z.), Department of Physiology and Cell Biology (B.Z., J.L.Z., M.J.K., M.T.Z.), The Ohio State University, Columbus; Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, HuBei, China (B.Z.); Department of Biostatistics (Y.S., M.X., F.E.H.), Division of Clinical Pharmacology, Department of Medicine (D.M.R., C.M.S.), Division of Cardiac Surgery, Department of Surgery (T.A.), Division of Cardiovascular Medicine (T. N., E. C., Y.R.S., D.R., C.L.G., Q.S.W, R.J.G.), Department of Pharmacology and Department of Pathology, Immunology, and Microbiology (R.J.G.), Vanderbilt University Medical Center, Nashville, TN
| | - Quinn S Wells
- From the Division of Cardiovascular Medicine, Davis Heart and Lung Research Institute (B.Z., D.G.W., Z.X., R.H., H.H., S.V., J.L.Z.), Department of Physiology and Cell Biology (B.Z., J.L.Z., M.J.K., M.T.Z.), The Ohio State University, Columbus; Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, HuBei, China (B.Z.); Department of Biostatistics (Y.S., M.X., F.E.H.), Division of Clinical Pharmacology, Department of Medicine (D.M.R., C.M.S.), Division of Cardiac Surgery, Department of Surgery (T.A.), Division of Cardiovascular Medicine (T. N., E. C., Y.R.S., D.R., C.L.G., Q.S.W, R.J.G.), Department of Pharmacology and Department of Pathology, Immunology, and Microbiology (R.J.G.), Vanderbilt University Medical Center, Nashville, TN
| | - Richard J Gumina
- From the Division of Cardiovascular Medicine, Davis Heart and Lung Research Institute (B.Z., D.G.W., Z.X., R.H., H.H., S.V., J.L.Z.), Department of Physiology and Cell Biology (B.Z., J.L.Z., M.J.K., M.T.Z.), The Ohio State University, Columbus; Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, HuBei, China (B.Z.); Department of Biostatistics (Y.S., M.X., F.E.H.), Division of Clinical Pharmacology, Department of Medicine (D.M.R., C.M.S.), Division of Cardiac Surgery, Department of Surgery (T.A.), Division of Cardiovascular Medicine (T. N., E. C., Y.R.S., D.R., C.L.G., Q.S.W, R.J.G.), Department of Pharmacology and Department of Pathology, Immunology, and Microbiology (R.J.G.), Vanderbilt University Medical Center, Nashville, TN.
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7
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Phospholamban is concentrated in the nuclear envelope of cardiomyocytes and involved in perinuclear/nuclear calcium handling. J Mol Cell Cardiol 2016; 100:1-8. [PMID: 27642167 DOI: 10.1016/j.yjmcc.2016.09.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2016] [Revised: 08/26/2016] [Accepted: 09/13/2016] [Indexed: 11/20/2022]
Abstract
AIMS Phospholamban (PLB) regulates the cardiac Ca2+-ATPase (SERCA2a) in sarcoplasmic reticulum (SR). However, the localization of PLB at subcellular sites outside the SR and possible contributions to Ca2+ cycling remain unknown. We examined the intracellular distribution of PLB and tested whether a pool of PLB exists in the nuclear envelope (NE) that might regulate perinuclear/nuclear Ca2+ (nCa2+) handling in cardiomyocytes (CMs). METHODS AND RESULTS Using confocal immunofluorescence microscopy and immunoblot analyses of CMs and CM nuclei, we discovered that PLB was highly concentrated in NE. Moreover, the ratio of PLB levels to SERCA levels was greater in NE than in SR. The increased levels of PLB in NE were a consistent finding using a range of antibodies, tissue samples, and species. To address a possible role in affecting Ca2+ handling, we used Fluo-4 based confocal Ca2+ imaging, with scan-lines across cytosol and nuclei, and evaluated the effects of PLB on cytosolic and nCa2+ uptake and release in mouse CMs. In intact CMs, isoproterenol increased amplitude and decreased the decay time of Ca2+ transients not only in cytosol but also in nuclear regions. In saponin-permeabilized mouse CMs ([Ca2+]i=400nM), we measured spontaneous Ca2+ waves after specific reversal of PLB activity by addition of the Fab fragment of an anti-PLB monoclonal antibody (100μg/ml). This highly selective immunological reagent enhanced Ca2+ uptake (faster decay times) and Ca2+ release (greater intensity) in both cytosol and across the nuclear regions. CONCLUSIONS Besides SR, PLB is concentrated in NE of CMs, and may be involved in modulation of nCa2+ dynamics.
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Sanoudou D, Kolokathis F, Arvanitis D, Al-Shafai K, Krishnamoorthy N, Buchan RJ, Walsh R, Tsiapras D, Barton PJ, Cook SA, Kremastinos D, Yacoub M. Genetic modifiers to the PLN L39X mutation in a patient with DCM and sustained ventricular tachycardia? Glob Cardiol Sci Pract 2015; 2015:29. [PMID: 26535225 PMCID: PMC4614339 DOI: 10.5339/gcsp.2015.29] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Accepted: 04/30/2015] [Indexed: 11/03/2022] Open
Affiliation(s)
- Despina Sanoudou
- 4 Dept. of Internal Medicine, Medical School, University of Athens, Greece. ; Biomedical Research Foundation of the Academy of Athens, Greece
| | | | | | - Kholoud Al-Shafai
- Qatar Cardiovascular Research Center (QCRC), Qatar Foundation, Doha, Qatar
| | | | - Rachel J Buchan
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton and Harefield NHS Foundation Trust, London, UK. ; National Heart & Lung Institute, Imperial College London, London, UK
| | - Roddy Walsh
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton and Harefield NHS Foundation Trust, London, UK. ; National Heart & Lung Institute, Imperial College London, London, UK
| | | | - Paul Jr Barton
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton and Harefield NHS Foundation Trust, London, UK. ; National Heart & Lung Institute, Imperial College London, London, UK
| | - Stuart A Cook
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton and Harefield NHS Foundation Trust, London, UK. ; National Heart & Lung Institute, Imperial College London, London, UK. ; NIHR Cardiovascular Biomedical Research Unit, Royal Brompton and Harefield NHS Foundation Trust, London, UK
| | | | - Magdi Yacoub
- Qatar Cardiovascular Research Center (QCRC), Qatar Foundation, Doha, Qatar. ; NIHR Cardiovascular Biomedical Research Unit, Royal Brompton and Harefield NHS Foundation Trust, London, UK
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9
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Liu GS, Morales A, Vafiadaki E, Lam CK, Cai WF, Haghighi K, Adly G, Hershberger RE, Kranias EG. A novel human R25C-phospholamban mutation is associated with super-inhibition of calcium cycling and ventricular arrhythmia. Cardiovasc Res 2015; 107:164-74. [PMID: 25852082 DOI: 10.1093/cvr/cvv127] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Accepted: 03/20/2015] [Indexed: 12/26/2022] Open
Abstract
AIMS Depressed sarcoplasmic reticulum (SR) Ca(2+) cycling, a universal characteristic of human and experimental heart failure, may be associated with genetic alterations in key Ca(2+)-handling proteins. In this study, we identified a novel PLN mutation (R25C) in dilated cardiomyopathy (DCM) and investigated its functional significance in cardiomyocyte Ca(2+)-handling and contractility. METHODS AND RESULTS Exome sequencing identified a C73T substitution in the coding region of PLN in a family with DCM. The four heterozygous family members had implantable cardiac defibrillators, and three developed prominent ventricular arrhythmias. Overexpression of R25C-PLN in adult rat cardiomyocytes significantly suppressed the Ca(2+) affinity of SR Ca(2+)-ATPase (SERCA2a), resulting in decreased SR Ca(2+) content, Ca(2+) transients, and impaired contractile function, compared with WT-PLN. These inhibitory effects were associated with enhanced interaction of R25C-PLN with SERCA2, which was prevented by PKA phosphorylation. Accordingly, isoproterenol stimulation relieved the depressive effects of R25C-PLN in cardiomyocytes. However, R25C-PLN also elicited increases in the frequency of Ca(2+) sparks and waves as well as stress-induced aftercontractions. This was accompanied by increased Ca(2+)/calmodulin-dependent protein kinase II activity and hyper-phosphorylation of RyR2 at serine 2814. CONCLUSION The findings demonstrate that human R25C-PLN is associated with super-inhibition of SERCA2a and Ca(2+) transport as well as increased SR Ca(2+) leak, promoting arrhythmogenesis under stress conditions. This is the first mechanistic evidence that increased PLN inhibition may impact both SR Ca(2+) uptake and Ca(2+) release activities and suggests that the human R25C-PLN may be a prognostic factor for increased ventricular arrhythmia risk in DCM carriers.
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Affiliation(s)
- Guan-Sheng Liu
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, PO Box 670575, 231 Albert Sabin Way, Cincinnati, OH, USA
| | - Ana Morales
- Division of Human Genetics, Ohio State University College of Medicine, Columbus, OH, USA Dorothy M. Davis Heart and Lung Research Institute, Ohio State University College of Medicine, Columbus, OH 45267-0575, USA
| | - Elizabeth Vafiadaki
- Molecular Biology Division, Biomedical Research Foundation, Academy of Athens, Greece
| | - Chi Keung Lam
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, PO Box 670575, 231 Albert Sabin Way, Cincinnati, OH, USA
| | - Wen-Feng Cai
- Department of Pathology and Laboratory Medicine, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Kobra Haghighi
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, PO Box 670575, 231 Albert Sabin Way, Cincinnati, OH, USA
| | - George Adly
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, PO Box 670575, 231 Albert Sabin Way, Cincinnati, OH, USA
| | - Ray E Hershberger
- Division of Human Genetics, Ohio State University College of Medicine, Columbus, OH, USA Dorothy M. Davis Heart and Lung Research Institute, Ohio State University College of Medicine, Columbus, OH 45267-0575, USA Division of Cardiovascular Medicine, Department of Internal Medicine, Ohio State University College of Medicine, Columbus, OH, USA
| | - Evangelia G Kranias
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, PO Box 670575, 231 Albert Sabin Way, Cincinnati, OH, USA Molecular Biology Division, Biomedical Research Foundation, Academy of Athens, Greece
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10
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Chen Z. Competitive displacement of wild-type phospholamban from the Ca2+-free cardiac calcium pump by phospholamban mutants with different binding affinities. J Mol Cell Cardiol 2014; 76:130-7. [DOI: 10.1016/j.yjmcc.2014.08.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2014] [Revised: 08/08/2014] [Accepted: 08/25/2014] [Indexed: 11/29/2022]
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11
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Abrol N, Smolin N, Armanious G, Ceholski DK, Trieber CA, Young HS, Robia SL. Phospholamban C-terminal residues are critical determinants of the structure and function of the calcium ATPase regulatory complex. J Biol Chem 2014; 289:25855-66. [PMID: 25074938 DOI: 10.1074/jbc.m114.562579] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
To determine the structural and regulatory role of the C-terminal residues of phospholamban (PLB) in the membranes of living cells, we fused fluorescent protein tags to PLB and sarco/endoplasmic reticulum calcium ATPase (SERCA). Alanine substitution of PLB C-terminal residues significantly altered fluorescence resonance energy transfer (FRET) from PLB to PLB and SERCA to PLB, suggesting a change in quaternary conformation of PLB pentamer and SERCA-PLB regulatory complex. Val to Ala substitution at position 49 (V49A) had particularly large effects on PLB pentamer structure and PLB-SERCA regulatory complex conformation, increasing and decreasing probe separation distance, respectively. We also quantified a decrease in oligomerization affinity, an increase in binding affinity of V49A-PLB for SERCA, and a gain of inhibitory function as quantified by calcium-dependent ATPase activity. Notably, deletion of only a few C-terminal residues resulted in significant loss of PLB membrane anchoring and mislocalization to the cytoplasm and nucleus. C-terminal truncations also resulted in progressive loss of PLB-PLB FRET due to a decrease in the apparent affinity of PLB oligomerization. We quantified a similar decrease in the binding affinity of truncated PLB for SERCA and loss of inhibitory potency. However, despite decreased SERCA-PLB binding, intermolecular FRET for Val(49)-stop (V49X) truncation mutant was paradoxically increased as a result of an 11.3-Å decrease in the distance between donor and acceptor fluorophores. We conclude that PLB C-terminal residues are critical for localization, oligomerization, and regulatory function. In particular, the PLB C terminus is an important determinant of the quaternary structure of the SERCA regulatory complex.
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Affiliation(s)
- Neha Abrol
- From the Department of Cell and Molecular Physiology, Loyola University Chicago, Maywood, Illinois 60153 and
| | - Nikolai Smolin
- From the Department of Cell and Molecular Physiology, Loyola University Chicago, Maywood, Illinois 60153 and
| | - Gareth Armanious
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Delaine K Ceholski
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Catharine A Trieber
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Howard S Young
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Seth L Robia
- From the Department of Cell and Molecular Physiology, Loyola University Chicago, Maywood, Illinois 60153 and
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12
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Koch SE, Haworth KJ, Robbins N, Smith MA, Lather N, Anjak A, Jiang M, Varma P, Jones WK, Rubinstein J. Age- and gender-related changes in ventricular performance in wild-type FVB/N mice as evaluated by conventional and vector velocity echocardiography imaging: a retrospective study. ULTRASOUND IN MEDICINE & BIOLOGY 2013; 39:2034-2043. [PMID: 23791351 PMCID: PMC4857602 DOI: 10.1016/j.ultrasmedbio.2013.04.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2012] [Revised: 03/28/2013] [Accepted: 04/04/2013] [Indexed: 06/02/2023]
Abstract
Detailed studies in animal models to assess the importance of aging animals in cardiovascular research are rather scarce. The increase in mouse models used to study cardiovascular disease makes the establishment of physiologic aging parameters in myocardial function in both male and female mice critical. Forty-four FVB/N mice were studied at multiple time points between the ages of 3 and 16 mo using high-frequency echocardiography. Our study found that there is an age-dependent decrease in several systolic and diastolic function parameters in male mice, but not in female mice. This study establishes the physiologic age- and gender-related changes in myocardial function that occur in mice and can be measured with echocardiography. We report baseline values for traditional echocardiography and advanced echocardiographic techniques to measure discrete changes in cardiac function in the commonly employed FVB/N strain.
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Affiliation(s)
- Sheryl E. Koch
- Internal Medicine, Division of Cardiology, University of Cincinnati, Cincinnati, Ohio, USA
| | - Kevin J. Haworth
- Internal Medicine, Division of Cardiology, University of Cincinnati, Cincinnati, Ohio, USA
- Biomedical Engineering Program, University of Cincinnati, Cincinnati, Ohio, USA
| | - Nathan Robbins
- Emergency Medicine, University of Cincinnati, Cincinnati, Ohio, USA
| | - Margaret A. Smith
- Internal Medicine, Division of Cardiology, University of Cincinnati, Cincinnati, Ohio, USA
| | - Navneet Lather
- Internal Medicine, Division of Cardiology, University of Cincinnati, Cincinnati, Ohio, USA
| | - Ahmad Anjak
- Internal Medicine, Division of Cardiology, University of Cincinnati, Cincinnati, Ohio, USA
| | - Min Jiang
- Internal Medicine, Division of Cardiology, University of Cincinnati, Cincinnati, Ohio, USA
| | - Priyanka Varma
- Internal Medicine, Division of Cardiology, University of Cincinnati, Cincinnati, Ohio, USA
| | - W. Keith Jones
- Department of Pharmacology & Cell Biophysics, University of Cincinnati, Cincinnati, Ohio, USA
| | - Jack Rubinstein
- Internal Medicine, Division of Cardiology, University of Cincinnati, Cincinnati, Ohio, USA
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13
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Sivakumaran V, Stanley BA, Tocchetti CG, Ballin JD, Caceres V, Zhou L, Keceli G, Rainer PP, Lee DI, Huke S, Ziolo MT, Kranias EG, Toscano JP, Wilson GM, O'Rourke B, Kass DA, Mahaney JE, Paolocci N. HNO enhances SERCA2a activity and cardiomyocyte function by promoting redox-dependent phospholamban oligomerization. Antioxid Redox Signal 2013; 19:1185-97. [PMID: 23919584 PMCID: PMC3785857 DOI: 10.1089/ars.2012.5057] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
AIMS Nitroxyl (HNO) interacts with thiols to act as a redox-sensitive modulator of protein function. It enhances sarcoplasmic reticular Ca(2+) uptake and myofilament Ca(2+) sensitivity, improving cardiac contractility. This activity has led to clinical testing of HNO donors for heart failure. Here we tested whether HNO alters the inhibitory interaction between phospholamban (PLN) and the sarcoplasmic reticulum Ca(2+)-ATPase (SERCA2a) in a redox-dependent manner, improving Ca(2+) handling in isolated myocytes/hearts. RESULTS Ventriculocytes, sarcoplasmic reticulum (SR) vesicles, and whole hearts were isolated from control (wildtype [WT]) or PLN knockout (pln(-/-)) mice. Compared to WT, pln(-/-) myocytes displayed enhanced resting sarcomere shortening, peak Ca(2+) transient, and blunted β-adrenergic responsiveness. HNO stimulated shortening, relaxation, and Ca(2+) transient in WT cardiomyocytes, and evoked positive inotropy/lusitropy in intact hearts. These changes were markedly blunted in pln(-/-) cells/hearts. HNO enhanced SR Ca(2+) uptake in WT but not pln(-/-) SR-vesicles. Spectroscopic studies in insect cell microsomes expressing SERCA2a±PLN showed that HNO increased Ca(2+)-dependent SERCA2a conformational flexibility but only when PLN was present. In cardiomyocytes, HNO achieved this effect by stabilizing PLN in an oligomeric disulfide bond-dependent configuration, decreasing the amount of free inhibitory monomeric PLN available. INNOVATION HNO-dependent redox changes in myocyte PLN oligomerization relieve PLN inhibition of SERCA2a. CONCLUSIONS PLN plays a central role in HNO-induced enhancement of SERCA2a activity, leading to increased inotropy/lusitropy in intact myocytes and hearts. PLN remains physically associated with SERCA2a; however, less monomeric PLN is available resulting in decreased inhibition of the enzyme. These findings offer new avenues to improve Ca(2+) handling in failing hearts.
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Affiliation(s)
- Vidhya Sivakumaran
- 1 Division of Cardiology, Johns Hopkins Medical Institutions , Baltimore, Maryland
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14
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Allosteric regulation of SERCA by phosphorylation-mediated conformational shift of phospholamban. Proc Natl Acad Sci U S A 2013; 110:17338-43. [PMID: 24101520 DOI: 10.1073/pnas.1303006110] [Citation(s) in RCA: 104] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The membrane protein complex between the sarcoplasmic reticulum Ca(2+)-ATPase (SERCA) and phospholamban (PLN) controls Ca(2+) transport in cardiomyocytes, thereby modulating cardiac contractility. β-Adrenergic-stimulated phosphorylation of PLN at Ser-16 enhances SERCA activity via an unknown mechanism. Using solid-state nuclear magnetic resonance spectroscopy, we mapped the physical interactions between SERCA and both unphosphorylated and phosphorylated PLN in membrane bilayers. We found that the allosteric regulation of SERCA depends on the conformational equilibrium of PLN, whose cytoplasmic regulatory domain interconverts between three different states: a ground T state (helical and membrane associated), an excited R state (unfolded and membrane detached), and a B state (extended and enzyme-bound), which is noninhibitory. Phosphorylation at Ser-16 of PLN shifts the populations toward the B state, increasing SERCA activity. We conclude that PLN's conformational equilibrium is central to maintain SERCA's apparent Ca(2+) affinity within a physiological window. This model represents a paradigm shift in our understanding of SERCA regulation by posttranslational phosphorylation and suggests strategies for designing innovative therapeutic approaches to enhance cardiac muscle contractility.
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15
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Gomes AC, Falcão-Pires I, Pires AL, Brás-Silva C, Leite-Moreira AF. Rodent models of heart failure: an updated review. Heart Fail Rev 2013; 18:219-49. [PMID: 22446984 DOI: 10.1007/s10741-012-9305-3] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Heart failure (HF) is one of the major health and economic burdens worldwide, and its prevalence is continuously increasing. The study of HF requires reliable animal models to study the chronic changes and pharmacologic interventions in myocardial structure and function and to follow its progression toward HF. Indeed, during the past 40 years, basic and translational scientists have used small animal models to understand the pathophysiology of HF and find more efficient ways of preventing and managing patients suffering from congestive HF (CHF). Each species and each animal model has advantages and disadvantages, and the choice of one model over another should take them into account for a good experimental design. The aim of this review is to describe and highlight the advantages and drawbacks of some commonly used HF rodents models, including both non-genetically and genetically engineered models, with a specific subchapter concerning diastolic HF models.
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Affiliation(s)
- A C Gomes
- Department of Physiology and Cardiothoracic Surgery, Faculty of Medicine, University of Porto, Alameda Professor Hernâni Monteiro, 4200-319, Porto, Portugal
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16
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Targeting protein-protein interactions within the cyclic AMP signaling system as a therapeutic strategy for cardiovascular disease. Future Med Chem 2013; 5:451-64. [PMID: 23495691 DOI: 10.4155/fmc.12.216] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The cAMP signaling system can trigger precise physiological cellular responses that depend on the fidelity of many protein-protein interactions, which act to bring together signaling intermediates at defined locations within cells. In the heart, cAMP participates in the fine control of excitation-contraction coupling, hence, any disregulation of this signaling cascade can lead to cardiac disease. Due to the ubiquitous nature of the cAMP pathway, general inhibitors of cAMP signaling proteins such as PKA, EPAC and PDEs would act non-specifically and universally, increasing the likelihood of serious 'off target' effects. Recent advances in the discovery of peptides and small molecules that disrupt the protein-protein interactions that underpin cellular targeting of cAMP signaling proteins are described and discussed.
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17
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Abstract
Heart disease remains the leading cause of death and disability in the Western world. Current therapies aim at treating the symptoms rather than the subcellular mechanisms, underlying the etiology and pathological remodeling in heart failure. A universal characteristic, contributing to the decreased contractile performance in human and experimental failing hearts, is impaired calcium sequestration into the sarcoplasmic reticulum (SR). SR calcium uptake is mediated by a Ca(2+)-ATPase (SERCA2), whose activity is reversibly regulated by phospholamban (PLN). Dephosphorylated PLN is an inhibitor of SERCA and phosphorylation of PLN relieves this inhibition. However, the initial simple view of a PLN/SERCA regulatory complex has been modified by our recent identification of SUMO, S100 and the histidine-rich Ca-binding protein as regulators of SERCA activity. In addition, PLN activity is regulated by 2 phosphoproteins, the inhibitor-1 of protein phosphatase 1 and the small heat shock protein 20, which affect the overall SERCA-mediated Ca-transport. This review will highlight the regulatory mechanisms of cardiac contractility by the multimeric SERCA/PLN-ensemble and the potential for new therapeutic avenues targeting this complex by using small molecules and gene transfer methods.
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Affiliation(s)
- Evangelia G Kranias
- Department of Pharmacology and Cell Biophysics, College of Medicine, University of Cincinnati, 231 Albert Sabin Way, Cincinnati, OH 45267-0575, USA.
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18
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Nagai T, Komuro I. Gene and cytokine therapy for heart failure: molecular mechanisms in the improvement of cardiac function. Am J Physiol Heart Circ Physiol 2012; 303:H501-12. [PMID: 22777420 DOI: 10.1152/ajpheart.00130.2012] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Despite significant advances in pharmacological and clinical treatment, heart failure (HF) remains a leading cause of morbidity and mortality worldwide. Many new therapeutic strategies, including cell transplantation, gene delivery, and cytokines or other small molecules, have been explored to treat HF. Recent advancement of our understanding of the molecules that regulate cardiac function uncover many of the therapeutic key molecules to treat HF. Furthermore, a theory of paracrine mechanism, which underlies the beneficial effects of cell therapy, leads us to search novel target molecules for genetic or pharmacological strategy. Gene therapy means delivery of genetic materials into cells to achieve therapeutic effects. Recently, gene transfer technology in the cardiovascular system has been improved and several therapeutic target genes have been started to examine in clinical research, and some of the promising results have been emerged. Among the various bioactive reagents, cytokines such as granulocyte colony-stimulating factor and erythropoietin have been well examined, and a number of clinical trials for acute myocardial infarction and chronic HF have been conducted. Although further research is needed in both preclinical and clinical areas in terms of molecular mechanisms, safety, and efficiency, both gene and cytokine therapy have a great possibility to open the new era of the treatment of HF.
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Affiliation(s)
- Toshio Nagai
- Department of Cardiovascular Science and Medicine, Chiba University Graduate School of Medicine, Chiba, Japan
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19
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Ceholski DK, Trieber CA, Holmes CFB, Young HS. Lethal, hereditary mutants of phospholamban elude phosphorylation by protein kinase A. J Biol Chem 2012; 287:26596-605. [PMID: 22707725 DOI: 10.1074/jbc.m112.382713] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
The sarcoplasmic reticulum calcium pump (SERCA) and its regulator, phospholamban, are essential components of cardiac contractility. Phospholamban modulates contractility by inhibiting SERCA, and this process is dynamically regulated by β-adrenergic stimulation and phosphorylation of phospholamban. Herein we reveal mechanistic insight into how four hereditary mutants of phospholamban, Arg(9) to Cys, Arg(9) to Leu, Arg(9) to His, and Arg(14) deletion, alter regulation of SERCA. Deletion of Arg(14) disrupts the protein kinase A recognition motif, which abrogates phospholamban phosphorylation and results in constitutive SERCA inhibition. Mutation of Arg(9) causes more complex changes in function, where hydrophobic substitutions such as cysteine and leucine eliminate both SERCA inhibition and phospholamban phosphorylation, whereas an aromatic substitution such as histidine selectively disrupts phosphorylation. We demonstrate that the role of Arg(9) in phospholamban function is multifaceted: it is important for inhibition of SERCA, it increases the efficiency of phosphorylation, and it is critical for protein kinase A recognition in the context of the phospholamban pentamer. Given the synergistic consequences on contractility, it is not surprising that the mutants cause lethal, hereditary dilated cardiomyopathy.
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Affiliation(s)
- Delaine K Ceholski
- Department of Biochemistry, University of Alberta, Edmonton, Alberta T6G 2H7, Canada
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20
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Tilgmann C, Pollesello P, Ovaska M, Kaivola J, Pystynen J, Tiainen E, Yliperttula M, Annila A, Levijoki J. Discovery and Structural Characterization of a Phospholamban-Binding Cyclic Peptide and Design of Novel Inhibitors of Phospholamban. Chem Biol Drug Des 2012; 81:463-73. [DOI: 10.1111/j.1747-0285.2012.01409.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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21
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Medeiros A, Biagi DG, Sobreira TJP, de Oliveira PSL, Negrão CE, Mansur AJ, Krieger JE, Brum PC, Pereira AC. Mutations in the human phospholamban gene in patients with heart failure. Am Heart J 2011; 162:1088-1095.e1. [PMID: 22137083 DOI: 10.1016/j.ahj.2011.07.028] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2011] [Accepted: 07/21/2011] [Indexed: 11/28/2022]
Abstract
BACKGROUND Phospholamban (PLN) is a crucial Ca(2+) cycling protein and a primary mediator of the β-adrenergic effects resulting in enhanced cardiac output. Mutations in the gene encoding PLN have been associated with idiopathic dilated cardiomyopathy; however, no systematic search for PLN mutations in heart failure has been conducted. METHODS We screened a cohort of 1,014 Brazilian patients with heart failure for mutations in the PLN gene. Molecular modeling studies of the mutations found were developed. Different disease etiologies were present in our sample: idiopathic, ischemic, Chagas, valvular, hypertensive, and others. RESULTS We identified 4 unrelated patients with PLN mutations (prevalence of 0.4%), 3 of them in the same amino acid residue (R9). Two patients presented a G-T missense mutation at the G26 nucleotide, which encodes an Arg-Leu substitution at codon 9 (R9L). One patient presented a G-A missense mutation at the same nucleotide, which encodes an Arg-His substitution at codon 9 (R9H). The fourth affected patient presented a T-G nonsense mutation at the nucleotide 116, substituting a termination codon for Leu-39 (L39stop). Molecular modeling studies suggested that R9L and R9H mutations might affect the region involved in protein kinase A docking and probably affect the mechanism modulating the release of phosphorylated PLN from the substrate binding site of protein kinase A. CONCLUSIONS Mutations in the PLN gene are a rare cause of heart failure, present almost exclusively in patients with dilated cardiomyopathy etiology. The Arg9 and Leu39 residues are the leading location of mutations described at this locus to date. Despite the few mutated residues described to date, the clinical spectrum of presentation appears to vary considerably.
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22
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Improving cardiac Ca⁺² transport into the sarcoplasmic reticulum in heart failure: lessons from the ubiquitous SERCA2b Ca⁺² pump. Biochem Soc Trans 2011; 39:781-7. [PMID: 21599649 DOI: 10.1042/bst0390781] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
As a major Ca2+ pump in the sarcoplasmic reticulum of the cardiomyocyte, SERCA2a (sarcoplasmic/endoplasmic reticulum Ca2+-ATPase 2a) controls the relaxation and contraction of the cardiomyocyte. It is meticulously regulated by adapting its expression levels and affinity for Ca2+ ions to the physiological demand of the heart. Dysregulation of the SERCA2a activity entails poor cardiomyocyte contractility, resulting in heart failure. Conversely, improving cardiac SERCA2a activity, e.g. by boosting its expression level or by increasing its affinity for Ca2+, is a promising strategy to rescue contractile dysfunction of the failing heart. The structures of the related SERCA1a Ca2+ pump and the Na+/K+-ATPase of the plasma membrane exposed the pumping mechanism and conserved domain architecture of these ion pumps. However, how the Ca2+ affinity of SERCA2a is regulated at the molecular level remained unclear. A structural and functional analysis of the closely related SERCA2b Ca2+ pump, i.e. the housekeeping Ca2+ pump found in the endoplasmic reticulum and the only SERCA isoform characterized by a high Ca2+ affinity, aimed to fill this gap. We demonstrated the existence of a novel and highly conserved site on the SERCA2 pump mediating Ca2+ affinity regulation by the unique C-terminus of SERCA2b (2b-tail). It differs from the earlier-described target site of the affinity regulator phospholamban. Targeting this novel site may provide a new approach to improve SERCA2a function in the failing heart. Strikingly, the intramembrane interaction site of the 2b-tail in SERCA2b shares sequence and structural homology with the binding site of the β-subunit on the α Na+/K+-ATPase. Thus P-type ATPases seem to have developed related mechanisms of regulation, and it is a future challenge for us to discover these general principles of P-type regulation.
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23
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Brum P, Bacurau A, Medeiros A, Ferreira J, Vanzelli A, Negrão C. Aerobic exercise training in heart failure: impact on sympathetic hyperactivity and cardiac and skeletal muscle function. Braz J Med Biol Res 2011; 44:827-35. [DOI: 10.1590/s0100-879x2011007500075] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2011] [Accepted: 06/06/2011] [Indexed: 01/01/2023] Open
Affiliation(s)
| | | | - A. Medeiros
- Universidade de São Paulo, Brasil; Universidade Federal de São Paulo, Brasil
| | | | | | - C.E. Negrão
- Universidade de São Paulo, Brasil; Universidade de São Paulo, Brasil
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24
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Raake PWJ, Tscheschner H, Reinkober J, Ritterhoff J, Katus HA, Koch WJ, Most P. Gene therapy targets in heart failure: the path to translation. Clin Pharmacol Ther 2011; 90:542-53. [PMID: 21866097 DOI: 10.1038/clpt.2011.148] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Heart failure (HF) is the common end point of cardiac diseases. Despite the optimization of therapeutic strategies and the consequent overall reduction in HF-related mortality, the key underlying intracellular signal transduction abnormalities have not been addressed directly. In this regard, the gaps in modern HF therapy include derangement of β-adrenergic receptor (β-AR) signaling, Ca(2+) disbalances, cardiac myocyte death, diastolic dysfunction, and monogenetic cardiomyopathies. In this review we discuss the potential of gene therapy to fill these gaps and rectify abnormalities in intracellular signaling. We also examine current vector technology and currently available vector-delivery strategies, and we delineate promising gene therapy structures. Finally, we analyze potential limitations related to the transfer of successful preclinical gene therapy approaches to HF treatment in the clinic, as well as impending strategies aimed at overcoming these limitations.
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Affiliation(s)
- P W J Raake
- Division of Cardiology, Department of Internal Medicine III, University of Heidelberg, Heidelberg, Germany
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25
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Vandecaetsbeek I, Vangheluwe P, Raeymaekers L, Wuytack F, Vanoevelen J. The Ca2+ pumps of the endoplasmic reticulum and Golgi apparatus. Cold Spring Harb Perspect Biol 2011; 3:cshperspect.a004184. [PMID: 21441596 DOI: 10.1101/cshperspect.a004184] [Citation(s) in RCA: 154] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The various splice variants of the three SERCA- and the two SPCA-pump genes in higher vertebrates encode P-type ATPases of the P(2A) group found respectively in the membranes of the endoplasmic reticulum and the secretory pathway. Of these, SERCA2b and SPCA1a represent the housekeeping isoforms. The SERCA2b form is characterized by a luminal carboxy terminus imposing a higher affinity for cytosolic Ca(2+) compared to the other SERCAs. This is mediated by intramembrane and luminal interactions of this extension with the pump. Other known affinity modulators like phospholamban and sarcolipin decrease the affinity for Ca(2+). The number of proteins reported to interact with SERCA is rapidly growing. Here, we limit the discussion to those for which the interaction site with the ATPase is specified: HAX-1, calumenin, histidine-rich Ca(2+)-binding protein, and indirectly calreticulin, calnexin, and ERp57. The role of the phylogenetically older and structurally simpler SPCAs as transporters of Ca(2+), but also of Mn(2+), is also addressed.
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Affiliation(s)
- Ilse Vandecaetsbeek
- Laboratory of Ca-transport ATPases, Department of Molecular Cell Biology, K.U. Leuven, Leuven, Belgium
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26
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Akin BL, Chen Z, Jones LR. Superinhibitory phospholamban mutants compete with Ca2+ for binding to SERCA2a by stabilizing a unique nucleotide-dependent conformational state. J Biol Chem 2010; 285:28540-52. [PMID: 20622261 DOI: 10.1074/jbc.m110.151779] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Three cross-linkable phospholamban (PLB) mutants of increasing inhibitory strength (N30C-PLB < N27A,N30C,L37A-PLB (PLB3) < N27A,N30C,L37A,V49G-PLB (PLB4)) were used to determine whether PLB decreases the Ca(2+) affinity of SERCA2a by competing for Ca(2+) binding. The functional effects of N30C-PLB, PLB3, and PLB4 on Ca(2+)-ATPase activity and E1 approximately P formation were correlated with their binding interactions with SERCA2a measured by chemical cross-linking. Successively higher Ca(2+) concentrations were required to both activate the enzyme co-expressed with N30C-PLB, PLB3, and PLB4 and to dissociate N30C-PLB, PLB3, and PLB4 from SERCA2a, suggesting competition between PLB and Ca(2+) for binding to SERCA2a. This was confirmed with the Ca(2+) pump mutant, D351A, which is catalytically inactive but retains strong Ca(2+) binding. Increasingly higher Ca(2+) concentrations were also required to dissociate N30C-PLB, PLB3, and PLB4 from D351A, demonstrating directly that PLB antagonizes Ca(2+) binding. Finally, the specific conformation of E2 (Ca(2+)-free state of SERCA2a) that binds PLB was investigated using the Ca(2+)-pump inhibitors thapsigargin and vanadate. Cross-linking assays conducted in the absence of Ca(2+) showed that PLB bound preferentially to E2 with bound nucleotide, forming a remarkably stable complex that is highly resistant to both thapsigargin and vanadate. In the presence of ATP, N30C-PLB had an affinity for SERCA2a approaching that of vanadate (micromolar), whereas PLB3 and PLB4 had much higher affinities, severalfold greater than even thapsigargin (nanomolar or higher). We conclude that PLB decreases Ca(2+) binding to SERCA2a by stabilizing a unique E2.ATP state that is unable to bind thapsigargin or vanadate.
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Affiliation(s)
- Brandy L Akin
- Krannert Institute of Cardiology and the Department of Biochemistry, Indiana University School of Medicine, Indianapolis, Indiana 46202, USA
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27
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Zhang ZY, Liu XH, Hu WC, Rong F, Wu XD. The calcineurin-myocyte enhancer factor 2c pathway mediates cardiac hypertrophy induced by endoplasmic reticulum stress in neonatal rat cardiomyocytes. Am J Physiol Heart Circ Physiol 2010; 298:H1499-509. [PMID: 20207814 DOI: 10.1152/ajpheart.00980.2009] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Endoplasmic reticulum (ER) stress (ERS) is involved in various cardiovascular diseases. Our previous study verified that ERS took part in the development of cardiac hypertrophy; however, its mechanism is still unclear. This study aimed to investigate the roles of the calcineurin (CaN) signal pathway in hypertrophy induced by the ERS inductor thapsigargin (TG) in neonatal cardiomyocytes from Sprague-Dawley rats. Investigation of ER chaperone expression, ER staining, and calreticulin immunofluorescence were used to detect the ERS response. mRNA expression of atrial natriuretic peptide and brain natriuretic peptide, total protein synthesis rate, and cell surface area were used to evaluate cardiac hypertrophy induced by TG. TG induced a significant ERS response along with hypertrophy in a dose- and time-dependent manner in cardiomyocytes, which was verified by treatment with tunicamycin, another ERS inducer. Furthermore, TG induced a significant elevation of the intracellular Ca(2+) level, CaN activation, and myocyte enhancer factor 2c (MEF2c) expression in a dose- and time-dependent manner in cardiomyocytes. Cyclosporine A, a CaN inhibitor, markedly suppressed MEF2c nuclear translocation and inhibited TG-induced hypertrophy. These results demonstrate that ERS induces cardiac hypertrophy and that the CaN-MEF2c pathway is involved in ERS-induced hypertrophy in cardiomyocytes.
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Affiliation(s)
- Zhen-Ying Zhang
- Department of Pathophysiology, Chinese PLA General Hospital, 28 Fuxing Road, Beijing, China
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28
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Cini G, Carpi A, Mechanick J, Cini L, Camici M, Galetta F, Giardino R, Russo M, Iervasi G. Thyroid hormones and the cardiovascular system: Pathophysiology and interventions. Biomed Pharmacother 2009; 63:742-53. [DOI: 10.1016/j.biopha.2009.08.003] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2009] [Accepted: 08/24/2009] [Indexed: 10/20/2022] Open
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The anti-apoptotic protein HAX-1 is a regulator of cardiac function. Proc Natl Acad Sci U S A 2009; 106:20776-81. [PMID: 19920172 DOI: 10.1073/pnas.0906998106] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The HS-1 associated protein X-1 (HAX-1) is a ubiquitously expressed protein that protects cardiomyocytes from programmed cell death. Here we identify HAX-1 as a regulator of contractility and calcium cycling in the heart. HAX-1 overexpression reduced sarcoplasmic reticulum Ca-ATPase (SERCA2) pump activity in isolated cardiomyocytes and in vivo, leading to depressed myocyte calcium kinetics and mechanics. Conversely, downregulation of HAX-1 enhanced calcium cycling and contractility. The inhibitory effects of HAX-1 were abolished upon phosphorylation of phospholamban, which plays a fundamental role in controlling basal contractility and constitutes a key downstream effector of the beta-adrenergic signaling cascade. Mechanistically, HAX-1 promoted formation of phospholamban monomers, the active/inhibitory units of the calcium pump. Indeed, ablation of PLN rescued HAX-1 inhibition of contractility in vivo. Thus, HAX-1 represents a regulatory mechanism in cardiac calcium cycling and its responses to sympathetic stimulation, implicating its importance in calcium homeostasis and cell survival.
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30
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Vandecaetsbeek I, Raeymaekers L, Wuytack F, Vangheluwe P. Factors controlling the activity of the SERCA2a pump in the normal and failing heart. Biofactors 2009; 35:484-99. [PMID: 19904717 DOI: 10.1002/biof.63] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Heart failure is the leading cause of death in western countries and is often associated with impaired Ca(2+) handling in the cardiomyocyte. In fact, cardiomyocyte relaxation and contraction are tightly controlled by the activity of the cardiac sarco(endo)plasmic reticulum (ER/SR) Ca(2+) pump SERCA2a, pumping Ca(2+) from the cytosol into the lumen of the ER/SR. This review addresses three important facets that control the SERCA2 activity in the heart. First, we focus on the alternative splicing of the SERCA2 messenger, which is strictly regulated in the developing heart. This splicing controls the formation of three SERCA2 splice variants with different enzymatic properties. Second, we will discuss the role and regulation of SERCA2a activity in the normal and failing heart. The two well-studied Ca(2+) affinity modulators phospholamban and sarcolipin control the activity of SERCA2a within a narrow window. An aberrantly high or low Ca(2+) affinity is often observed in and may even trigger cardiac failure. Correcting SERCA2a activity might therefore constitute a therapeutic approach to improve the contractility of the failing heart. Finally, we address the controversies and unanswered questions of other putative regulators of the cardiac Ca(2+) pump, such as sarcalumenin, HRC, S100A1, Bcl-2, HAX-1, calreticulin, calnexin, ERp57, IRS-1, and -2.
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Affiliation(s)
- Ilse Vandecaetsbeek
- Department of Molecular Cell Biology, Laboratory of Ca(2+)-transport ATPases, K.U.Leuven, Leuven, Belgium
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Abstract
Oxysterols are biologically active molecules that result from the oxidation of cholesterol. Several oxysterols are found in macrophages and macrophage-derived 'foam cells' in atherosclerotic tissue. Lipophilic oxysterols penetrate cell membranes and, therefore, their concentrations can reach harmful levels in endothelial and smooth muscle cells located in close proximity to the atherosclerotic plaques or inflammatory zones. New findings suggest that the effects of oxysterols on cardiomyocytes can lead to cell hypertrophy and death. This may make oxysterols one of the major factors precipitating morbidity in atherosclerosis-induced cardiac diseases and inflammation-induced heart complications. The pathological actions of oxysterols on muscle cells were shown to depend on dysfunctional Ca(2+) signaling; however, the mechanisms of the effects remain to be elucidated. Understanding the effects of oxysterols could lead to therapies that modulate malfunction of cardiomyocytes. This review discusses the experimental findings and the relevance of oxysterols to heart failure, and suggests strategies for important future investigations.
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Affiliation(s)
- Valeriy Lukyanenko
- Medical Biotechnology Center, University of Maryland Biotechnology Institute, Baltimore, MD 21201, USA.
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32
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Lukyanenko V, Chikando A, Lederer WJ. Mitochondria in cardiomyocyte Ca2+ signaling. Int J Biochem Cell Biol 2009; 41:1957-71. [PMID: 19703657 PMCID: PMC3522519 DOI: 10.1016/j.biocel.2009.03.011] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2008] [Revised: 03/20/2009] [Accepted: 03/26/2009] [Indexed: 10/20/2022]
Abstract
Ca(2+) signaling is of vital importance to cardiac cell function and plays an important role in heart failure. It is based on sarcolemmal, sarcoplasmic reticulum and mitochondrial Ca(2+) cycling. While the first two are well characterized, the latter remains unclear, controversial and technically challenging. In mammalian cardiac myocytes, Ca(2+) influx through L-type calcium channels in the sarcolemmal membrane triggers Ca(2+) release from the nearby junctional sarcoplasmic reticulum to produce Ca(2+) sparks. When this triggering is synchronized by the cardiac action potential, a global [Ca(2+)](i) transient arises from coordinated Ca(2+) release events. The ends of intermyofibrillar mitochondria are located within 20 nm of the junctional sarcoplasmic reticulum and thereby experience a high local [Ca(2+)] during the Ca(2+) release process. Both local and global Ca(2+) signals may thus influence calcium signaling in mitochondria and, reciprocally, mitochondria may contribute to the local control of calcium signaling. In addition to the intermyofibrillar mitochondria, morphologically distinct mitochondria are also located in the perinuclear and subsarcolemmal regions of the cardiomyocyte and thus experience a different local [Ca(2+)]. Here we review the literature in regard to several issues of broad interest: (1) the ultrastructural basis for mitochondrion - sarcoplasmic reticulum cross-signaling; (2) mechanisms of sarcoplasmic reticulum signaling; (3) mitochondrial calcium signaling; and (4) the possible interplay of calcium signaling between the sarcoplasmic reticulum and adjacent mitochondria. Finally, this review discusses experimental findings and mathematical models of cardiac calcium signaling between the sarcoplasmic reticulum and mitochondria, identifies weaknesses in these models, and suggests strategies and approaches for future investigations.
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Affiliation(s)
- Valeriy Lukyanenko
- Medical Biotechnology Center, University of Maryland Biotechnology Institute, Baltimore, MD 21201, USA.
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33
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Abstract
Biological sex plays an important role in normal cardiac physiology as well as in the heart's response to cardiac disease. Women generally have better cardiac function and survival than do men in the face of cardiac disease; however, this sex difference is lost when comparing postmenopausal women with age-matched men. Animal models of cardiac disease mirror what is seen in humans. Sex steroid hormones contribute significantly to sex-based differences in cardiac disease outcomes. Estrogen is generally considered to be cardioprotective, whereas testosterone is thought to be detrimental to heart function. Environmental estrogen-like molecules, such as phytoestrogens, can also affect cardiac physiology in both a positive and a negative manner.
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Affiliation(s)
- Elizabeth D Luczak
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, Colorado 80309, USA.
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Tanaka Y, Honda T, Matsuura K, Kimura Y, Inui M. In vitro selection and characterization of DNA aptamers specific for phospholamban. J Pharmacol Exp Ther 2009; 329:57-63. [PMID: 19158349 DOI: 10.1124/jpet.108.149526] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Calcium transport across the membrane of the sarcoplasmic reticulum (SR) plays an important role in the regulation of heart muscle contraction and relaxation. The sarco(endo)plasmic reticulum Ca(2+) ATPase (SERCA) 2a is responsible for Ca(2+) up-take by this organelle and is inhibited in a reversible manner by phospholamban, another SR membrane protein. Thus, alleviation of phospholamban-mediated inhibition of SERCA2a is a potential therapeutic option for heart failure and cardiomyopathy. We have now applied the systematic evolution of ligands by exponential enrichment protocol to a library of single-stranded DNA molecules containing a randomized 40-nucleotide sequence to isolate aptamers that bind phospholamban. One of the obtained aptamers, designated Apt-9, was found to specifically bind to the cytoplasmic region of phospholamban in vitro with high affinity (dissociation constant, approximately 20 nM). Apt-9 increased the Ca(2+)-dependent ATPase activity of cardiac SR vesicles but not that of SR vesicles from skeletal muscle in a concentration-dependent manner. It also shifted the Ca(2+) concentration-response curve for this ATPase activity to the left. These effects of Apt-9 were not mimicked by an oligonucleotide with a scrambled version of the Apt-9 sequence. Thus, our results indicate that Apt-9 activates SERCA2a by alleviating the inhibitory effect of phospholamban on this ATPase, and they suggest that phospholamban-specific aptamers warrant further investigation as potential therapeutic agents for heart failure and cardiomyopathy.
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Affiliation(s)
- Yoshie Tanaka
- Department of Pharmacology, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi 755-8505, Japan
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Seong MH, Bae JW. Recent Advances in Gene Therapy Targeted to Intracellular Calcium Transport for Heart Failure. Chonnam Med J 2009. [DOI: 10.4068/cmj.2009.45.3.145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Affiliation(s)
- Mun Hyuk Seong
- Department of Internal Medicine, Chungbuk National University School of Medicine, Cheongju, Korea
| | - Jang-Whan Bae
- Chungbuk Regional Cardiac Disease Center, Chungbuk National University Hospital, Cheongju, Korea
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36
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The role of thyroid hormone in the pathophysiology of heart failure: clinical evidence. Heart Fail Rev 2008; 15:155-69. [DOI: 10.1007/s10741-008-9126-6] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2008] [Accepted: 11/06/2008] [Indexed: 11/26/2022]
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Abstract
With increasing knowledge of basic molecular mechanisms governing the development of heart failure (HF), the possibility of specifically targeting key pathological players is evolving. Technology allowing for efficient in vivo transduction of myocardial tissue with long-term expression of a transgene enables translation of basic mechanistic knowledge into potential gene therapy approaches. Gene therapy in HF is in its infancy clinically with the predominant amount of experience being from animal models. Nevertheless, this challenging and promising field is gaining momentum as recent preclinical studies in larger animals have been carried out and, importantly, there are 2 newly initiated phase I clinical trials for HF gene therapy. To put it simply, 2 parameters are needed for achieving success with HF gene therapy: (1) clearly identified detrimental/beneficial molecular targets; and (2) the means to manipulate these targets at a molecular level in a sufficient number of cardiac cells. However, several obstacles do exist on our way to efficient and safe gene transfer to human myocardium. Some of these obstacles are discussed in this review; however, it primarily focuses on the molecular target systems that have been subjected to intense investigation over the last decade in an attempt to make gene therapy for human HF a reality.
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Affiliation(s)
- Leif Erik Vinge
- Center for Translational Medicine, George Zallie and Family Laboratory for Cardiovascular Gene Therapy, Thomas Jefferson University, Philadelphia, PA 19107, USA
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38
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Arvanitis DA, Sanoudou D, Kolokathis F, Vafiadaki E, Papalouka V, Kontrogianni-Konstantopoulos A, Theodorakis GN, Paraskevaidis IA, Adamopoulos S, Dorn GW, Kremastinos DT, Kranias EG. The Ser96Ala variant in histidine-rich calcium-binding protein is associated with life-threatening ventricular arrhythmias in idiopathic dilated cardiomyopathy. Eur Heart J 2008; 29:2514-25. [PMID: 18617481 PMCID: PMC2567024 DOI: 10.1093/eurheartj/ehn328] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Aims To investigate whether genetic variants of the histidine-rich calcium (HRC)-binding protein are associated with idiopathic dilated cardiomyopathy (DCM) and its progression. Methods and results We screened 123 idiopathic DCM patients and 96 healthy individuals by single-strand conformation polymorphism analysis and direct sequencing for genetic variants in HRC. Six polymorphisms were detected: Leu35Leu (A/G), Ser43Asn (G/A), Ser96Ala (T/G), Glu202_Glu203insGlu (−/GAG), Asp261del (GAT/−), and an in-frame insertion of 51 amino acids at His321. The analysis of their frequencies did not reveal any significant correlation with DCM development. However, the Ser96Ala polymorphism exhibited a statistically significant correlation with the occurrence of life-threatening ventricular arrhythmias. During a follow-up of 4.02 ± 2.4 years, the risk for ventricular arrhythmias was higher (HR, 9.620; 95% CI, 2.183–42.394; P = 0.003) in the Ala/Ala patients, compared with Ser/Ser homozygous patients. On multivariable Cox regression analysis, the Ser96Ala polymorphism was the only significant genetic arrythmogenesis predictor in DCM patients (HR, 4.191; 95% CI, 0.838–20.967; P = 0.018). Conclusion The Ser96Ala genetic variant of HRC is associated with life-threatening ventricular arrhythmias in idiopathic DCM and may serve as an independent predictor of susceptibility to arrhythmogenesis in the setting of DCM.
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Affiliation(s)
- Demetrios A Arvanitis
- Molecular Biology Division, Biomedical Research Foundation, Academy of Athens, Athens, Greece
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Vafiadaki E, Papalouka V, Arvanitis DA, Kranias EG, Sanoudou D. The role of SERCA2a/PLN complex, Ca2+ homeostasis, and anti-apoptotic proteins in determining cell fate. Pflugers Arch 2008; 457:687-700. [DOI: 10.1007/s00424-008-0506-5] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2008] [Accepted: 03/22/2008] [Indexed: 12/14/2022]
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40
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Caldwell PT, Thorne PA, Johnson PD, Boitano S, Runyan RB, Selmin O. Trichloroethylene disrupts cardiac gene expression and calcium homeostasis in rat myocytes. Toxicol Sci 2008; 104:135-43. [PMID: 18411232 DOI: 10.1093/toxsci/kfn078] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We have been investigating the molecular mechanisms by which trichloroethylene (TCE) might induce cardiac malformations in the embryonic heart. Previous results indicated that TCE disrupted expression of genes encoding proteins involved in regulation of intracellular Ca2+, [Ca2+](i), in cardiac cells, including ryanodine receptor isoform 2 (Ryr2), and sarcoendoplasmatic reticulum Ca2+ ATPase, Serca2a. These observations are important in light of the notion that altered cardiac contractility can produce morphological defects. The hypothesis tested in this study is that the TCE-induced changes in gene expression of Ca2+-associated proteins resulted in altered Ca2+ flux regulation. We used real-time PCR and digital imaging microscopy to characterize effects of various doses of TCE on gene expression and Ca2+ response to vasopressin (VP) in rat cardiac H9c2 myocytes. We observed a reduction in Serca2a and Ryr2 expression at 12 and 48 h after exposure to TCE. In addition, we found significant differences in Ca2+ response to VP in cells treated with TCE doses as low as 10 parts per billion. Taken all together, our data strongly indicate that exposure to TCE disrupts the ability of myocytes to regulate cellular Ca2+ fluxes. Perturbation of calcium signaling alters cardiac cell physiology and signal transduction and may hint to morphogenetic consequences in the context of heart development. These results point to a novel area of TCE biology and, if confirmed in vivo, may help to explain the apparent cardio-specific toxicity of TCE exposure in the rodent embryo.
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Affiliation(s)
- Patricia T Caldwell
- Department of Veterinary Science & Microbiology, University of Arizona, Tucson, Arizona 85721, USA
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41
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Haddad GE, Saunders LJ, Crosby SD, Carles M, del Monte F, King K, Bristow MR, Spinale FG, Macgillivray TE, Semigran MJ, Dec GW, Williams SA, Hajjar RJ, Gwathmey JK. Human cardiac-specific cDNA array for idiopathic dilated cardiomyopathy: sex-related differences. Physiol Genomics 2008; 33:267-77. [DOI: 10.1152/physiolgenomics.00265.2007] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Idiopathic dilated cardiomyopathy (IDCM) constitutes a large portion of patients with heart failure of unknown etiology. Up to 50% of all transplant recipients carry this clinical diagnosis. Female-specific gene expression in IDCM has not been explored. We report sex-related differences in the gene expression profile of ventricular myocardium from patients undergoing cardiac transplantation. We produced and sequenced subtractive cDNA libraries, using human left ventricular myocardium obtained from male transplant recipients with IDCM and nonfailing human heart donors. With the resulting sequence data, we generated a custom human heart failure microarray for IDCM containing 1,145 cardiac-specific oligonucleotide probes. This array was used to characterize RNA samples from female IDCM transplant recipients. We identified a female gene expression pattern that consists of 37 upregulated genes and 18 downregulated genes associated with IDCM. Upon functional analysis of the gene expression pattern, deregulated genes unique to female IDCM were those that are involved in energy metabolism and regulation of transcription and translation. For male patients we found deregulation of genes related to muscular contraction. These data suggest that 1) the gene expression pattern we have detected for IDCM may be specific for this disease and 2) there is a sex-specific profile to IDCM. Our observations further suggest for the first time ever novel targets for treatment of IDCM in women and men.
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Affiliation(s)
- Georges E. Haddad
- Department of Physiology and Biophysics, College of Medicine, Howard University, Washington, District of Columbia
| | | | - Seth D. Crosby
- Microarray Core Facility, Washington University Medical School, St. Louis, Missouri
| | - Maria Carles
- Gwathmey, Incorporated, Cambridge, Massachusetts
| | - Federica del Monte
- Cardiovascular Research Center, Beth Israel Deaconess Medical Center, Boston, Massachusetts
| | - Kindra King
- Gwathmey, Incorporated, Cambridge, Massachusetts
| | - Michael R. Bristow
- Division of Cardiology, School of Medicine, University of Colorado Health Sciences Center, Denver, Colorado
| | - Francis G. Spinale
- Cardiothoracic Surgery, Medical University of South Carolina, Charleston, South Carolina
| | | | - Marc J. Semigran
- Cardiology Division, Gray/Bigelow, Massachusetts General Hospital, Boston
| | - G. William Dec
- Cardiology Division, Gray/Bigelow, Massachusetts General Hospital, Boston
| | - Steven A. Williams
- Department of Biological Sciences, Smith College, Northampton, Massachusetts
| | - Roger J. Hajjar
- Cardiovascular Research Center, Mount Sinai School of Medicine, New York, New York
| | - Judith K. Gwathmey
- Gwathmey, Incorporated, Cambridge, Massachusetts
- Boston University School of Medicine, Cambridge, Massachusetts
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42
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Medeiros A, Rolim NPL, Oliveira RSF, Rosa KT, Mattos KC, Casarini DE, Irigoyen MC, Krieger EM, Krieger JE, Negrão CE, Brum PC. Exercise training delays cardiac dysfunction and prevents calcium handling abnormalities in sympathetic hyperactivity-induced heart failure mice. J Appl Physiol (1985) 2008; 104:103-9. [DOI: 10.1152/japplphysiol.00493.2007] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Exercise training (ET) is a coadjuvant therapy in preventive cardiology. It delays cardiac dysfunction and exercise intolerance in heart failure (HF); however, the molecular mechanisms underlying its cardioprotection are poorly understood. We tested the hypothesis that ET would prevent Ca2+ handling abnormalities and ventricular dysfunction in sympathetic hyperactivity-induced HF mice. A cohort of male wild-type (WT) and congenic α2A/α2C-adrenoceptor knockout (α2A/α2CARKO) mice with C57BL6/J genetic background (3–5 mo of age) were randomly assigned into untrained and exercise-trained groups. ET consisted of 8-wk swimming session, 60 min, 5 days/wk. Fractional shortening (FS) was assessed by two-dimensional guided M-mode echocardiography. The protein expression of ryanodine receptor (RyR), phospho-Ser2809-RyR, sarcoplasmic reticulum Ca2+ ATPase (SERCA2), Na+/Ca2+ exchanger (NCX), phospholamban (PLN), phospho-Ser16-PLN, and phospho-Thr17-PLN were analyzed by Western blotting. At 3 mo of age, no significant difference in FS and exercise tolerance was observed between WT and α2A/α2CARKO mice. At 5 mo, when cardiac dysfunction is associated with lung edema and increased plasma norepinephrine levels, α2A/α2CARKO mice presented reduced FS paralleled by decreased SERCA2 (26%) and NCX (34%). Conversely, α2A/α2CARKO mice displayed increased phospho-Ser16-PLN (76%) and phospho-Ser2809-RyR (49%). ET in α2A/α2CARKO mice prevented exercise intolerance, ventricular dysfunction, and decreased plasma norepinephrine. ET significantly increased the expression of SERCA2 (58%) and phospho-Ser16-PLN (30%) while it restored the expression of phospho-Ser2809-RyR to WT levels. Collectively, we provide evidence that improved net balance of Ca2+ handling proteins paralleled by a decreased sympathetic activity on ET are, at least in part, compensatory mechanisms against deteriorating ventricular function in HF.
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43
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Mu J, Qu D, Bartczak A, Phillips MJ, Manuel J, He W, Koscik C, Mendicino M, Zhang L, Clark DA, Grant DR, Backx PH, Levy GA, Adamson SL. Fgl2 deficiency causes neonatal death and cardiac dysfunction during embryonic and postnatal development in mice. Physiol Genomics 2007; 31:53-62. [PMID: 17550996 DOI: 10.1152/physiolgenomics.00026.2007] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
We hypothesized that cardiac dysfunction was responsible for the high perinatal lethality that we previously reported in fibrinogen-like protein 2 (Fgl2) knockout (KO) mice. We therefore used ultrasound biomicroscopy to assess left ventricular (LV) cardiac structure and function during development in Fgl2 KO and wild-type (WT) mice. The only deaths observed between embryonic day (E)8.5 (onset of heart beating) and postnatal day (P)28 (weaning) were within 3 days after birth, when 33% of Fgl2 KO pups died. Histopathology and Doppler assessments suggested that death was due to acute congestive cardiac failure without evidence of valvular or other obvious cardiac structural abnormalities. Heart rates in Fgl2 KO embryos were significantly reduced at E8.5 and E17.5, and irregular heart rhythms were significantly more common in Fgl2 KO (21/26) than WT (2/21) embryos at E13.5. Indexes of systolic and/or diastolic cardiac function were also abnormal in KO mice at E13.5 and E17.5, in postnatal mice studied at P1, and in KO mice surviving to P28. M-mode analysis showed no difference in LV diastolic chamber dimension, although posterior wall thickness was thinner at P7 and P28 in Fgl2 KO mice. We conclude that Fgl2 deficiency is not associated with obvious structural cardiac defects but is associated with a high incidence of neonatal death as well as contractile dysfunction and rhythm abnormalities during embryonic and postnatal development in mice.
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Affiliation(s)
- Junwu Mu
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada
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Rodriguez P, Mitton B, Nicolaou P, Chen G, Kranias EG. Phosphorylation of human inhibitor-1 at Ser67 and/or Thr75 attenuates stimulatory effects of protein kinase A signaling in cardiac myocytes. Am J Physiol Heart Circ Physiol 2007; 293:H762-9. [PMID: 17416610 DOI: 10.1152/ajpheart.00104.2007] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The depressed function of failing hearts has been partially attributed to increased protein phosphatase-1 through its impaired regulation by inhibitor-1. Phosphorylation of inhibitor-1 at Thr35 by PKA results in potent inhibition of protein phosphatase-1 activity, while phosphorylation at Ser67 or Thr75 by PKC attenuates the inhibitory activity. To examine the functional role of dual-site (Ser67, Thr75) phosphorylation of inhibitor-1 by PKC, the constitutively phosphorylated Ser67 (S67D) and/or Thr75 (T75D) human inhibitor-1 forms were expressed in adult cardiomyocytes. Expression of either single or double phosphorylated inhibitor-1 was associated with similar decreases in cardiac contractility, indicating that maximal inhibition can be elicited by each of these sites alone and that their inhibitory effects are not additive. Notably, activation of the cAMP pathway could only partially reverse the depressed contractile parameters. Accordingly, protein phosphatase-1 activity remained elevated, phosphorylation of phospholamban at Ser16 was decreased, and the EC(50) values of the sarcoplasmic reticulum calcium transport system were higher compared with controls. Thus phosphorylation of Ser67 and/or Thr75 in inhibitor-1 may mitigate the stimulatory effects of the cAMP pathway, resulting in compromised cardiac function.
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Affiliation(s)
- Patricia Rodriguez
- Department of Pharmacology and Cell Biophysics, University of Cincinnati, College of Medicine, 231 Albert Sabin Way, Cincinnati, OH 45267-0575, USA
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45
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De Keulenaer GW, Brutsaert DL. Systolic and diastolic heart failure: Different phenotypes of the same disease? Eur J Heart Fail 2007; 9:136-43. [PMID: 16884955 DOI: 10.1016/j.ejheart.2006.05.014] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2005] [Revised: 02/20/2006] [Accepted: 05/24/2006] [Indexed: 11/16/2022] Open
Abstract
Traditional pathophysiological concepts of chronic heart failure have largely focused on the haemodynamic consequences of ventricular systolic dysfunction. How these concepts relate to the pathophysiology of diastolic heart failure, i.e., heart failure with a preserved ejection fraction is, however, unclear, causing uncertainty about pathophysiology, diagnosis and management. Recent measurements of regional myocardial systolic function in patients with diastolic heart failure indicate that systolic and diastolic heart failure may be more closely related than previously anticipated. Rather than being considered as separate diseases with a distinct pathophysiology, systolic and diastolic heart failure may be merely different clinical presentations within a phenotypic spectrum of one and the same disease. In this review, we will interpret these new insights in a broader conceptual context of chronic heart failure and design novel paradigms in which systolic and diastolic heart failure jointly progress in a pathophysiological time trajectory of only one disease.
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46
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Vafiadaki E, Sanoudou D, Arvanitis DA, Catino DH, Kranias EG, Kontrogianni-Konstantopoulos A. Phospholamban Interacts with HAX-1, a Mitochondrial Protein with Anti-apoptotic Function. J Mol Biol 2007; 367:65-79. [PMID: 17241641 DOI: 10.1016/j.jmb.2006.10.057] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2006] [Revised: 10/11/2006] [Accepted: 10/16/2006] [Indexed: 01/29/2023]
Abstract
Phospholamban (PLN) is a key regulator of Ca(2+) homeostasis and contractility in the heart. Its regulatory effects are mediated through its interaction with the sarcoplasmic reticulum Ca(2+)-ATPase, (SERCA2a), resulting in alterations of its Ca(2+)-affinity. To identify additional proteins that may interact with PLN, we used the yeast-two-hybrid system to screen an adult human cardiac cDNA library. HS-1 associated protein X-1 (HAX-1) was identified as a PLN-binding partner. The minimal binding regions were mapped to amino acid residues 203-245 for HAX-1 and residues 16-22 for PLN. The interaction between the two proteins was confirmed using GST-HAX-1, bound to the glutathione-matrix, which specifically adsorbed native PLN from human or mouse cardiac homogenates, while in reciprocal binding studies, recombinant His-HAX-1 bound GST-PLN. Kinetic studies using surface plasmon resonance yielded a K(D) of approximately 1 muM as the binding affinity for the PLN/HAX-1 complex. Phosphorylation of PLN by cAMP-dependent protein kinase reduced binding to HAX-1, while increasing concentrations of Ca(2+) diminished the PLN/HAX-1 interaction in a dose-dependent manner. HAX-1 concentrated to mitochondria, but upon transient co-transfection of HEK 293 cells with PLN, HAX-1 redistributed and co-localized with PLN at the endoplasmic reticulum. Analysis of the anti-apoptotic function of HAX-1 revealed that the presence of PLN enhanced the HAX-1 protective effects from hypoxia/reoxygenation-induced cell death. These findings suggest a possible link between the Ca(2+) handling by the sarcoplasmic reticulum and cell survival mediated by the PLN/HAX-1 interaction.
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Affiliation(s)
- Elizabeth Vafiadaki
- Molecular Biology Division, Center for Basic Research, Foundation for Biomedical Research of the Academy of Athens, Soranou Efesiou 4, Athens 115 27, Greece
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47
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de Keulenaer GW, Brutsaert DL. Pathophysiology and Clinical Impact of Diastolic Heart Failure. CARDIOVASCULAR MEDICINE 2007. [DOI: 10.1007/978-1-84628-715-2_56] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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48
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Vangheluwe P, Sipido KR, Raeymaekers L, Wuytack F. New perspectives on the role of SERCA2's Ca2+ affinity in cardiac function. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2006; 1763:1216-28. [PMID: 17005265 DOI: 10.1016/j.bbamcr.2006.08.025] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2006] [Accepted: 08/10/2006] [Indexed: 11/21/2022]
Abstract
Cardiomyocyte relaxation and contraction are tightly controlled by the activity of the cardiac sarco(endo)plasmic reticulum (SR) Ca2+ transport ATPase (SERCA2a). The SR Ca2+ -uptake activity not only determines the speed of Ca(2+) removal during relaxation, but also the SR Ca2+ content and therefore the amount of Ca2+ released for cardiomyocyte contraction. The Ca2+ affinity is the major determinant of the pump's activity in the physiological Ca2+ concentration range. In the heart, the affinity of the pump for Ca2+ needs to be controlled between narrow borders, since an imbalanced affinity may evoke hypertrophic cardiomyopathy. Several small proteins (phospholamban, sarcolipin) adjust the Ca2+ affinity of the pump to the physiological needs of the cardiomyocyte. It is generally accepted that a chronically reduced Ca2+ affinity of the pump contributes to depressed SR Ca2+ handling in heart failure. Moreover, a persistently lower Ca2+ affinity is sufficient to impair cardiomyocyte SR Ca2+ handling and contractility inducing dilated cardiomyopathy in mice and humans. Conversely, the expression of SERCA2a, a pump with a lower Ca2+ affinity than the housekeeping isoform SERCA2b, is crucial to maintain normal cardiac function and growth. Novel findings demonstrated that a chronically increased Ca2+ affinity also may trigger cardiac hypertrophy in mice and humans. In addition, recent studies suggest that some models of heart failure are marked by a higher affinity of the pump for Ca2+, and hence by improved cardiomyocyte relaxation and contraction. Depressed cardiomyocyte SR Ca2+ uptake activity may therefore not be a universal hallmark of heart failure.
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Affiliation(s)
- P Vangheluwe
- Laboratory of Physiology, University of Leuven, Herestraat 49, bus 802, B-3000 Leuven, Belgium.
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49
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Luckey SW, Mansoori J, Fair K, Antos CL, Olson EN, Leinwand LA. Blocking cardiac growth in hypertrophic cardiomyopathy induces cardiac dysfunction and decreased survival only in males. Am J Physiol Heart Circ Physiol 2006; 292:H838-45. [PMID: 17012357 DOI: 10.1152/ajpheart.00615.2006] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Mutations in myosin heavy chain (MyHC) can cause hypertrophic cardiomyopathy (HCM) that is characterized by hypertrophy, histopathology, contractile dysfunction, and sudden death. The signaling pathways involved in the pathology of HCM have not been elucidated, and an unresolved question is whether blocking hypertrophic growth in HCM may be maladaptive or beneficial. To address these questions, a mouse model of HCM was crossed with an antihypertrophic mouse model of constitutive activated glycogen synthase kinase-3beta (caGSK-3beta). Active GSK-3beta blocked cardiac hypertrophy in both male and female HCM mice. However, doubly transgenic males (HCM/GSK-3beta) demonstrated depressed contractile function, reduced sarcoplasmic (endo) reticulum Ca(2+)-ATPase (SERCA) expression, elevated atrial natriuretic factor (ANF) expression, and premature death. In contrast, female HCM/GSK-3beta double transgenic mice exhibited similar cardiac histology, function, and survival to their female HCM littermates. Remarkably, dietary modification from a soy-based diet to a casein-based diet significantly improved survival in HCM/GSK-3beta males. These findings indicate that activation of GSK-3beta is sufficient to limit cardiac growth in this HCM model and the consequence of caGSK-3beta was sexually dimorphic. Furthermore, these results show that blocking hypertrophy by active GSK-3beta in this HCM model is not therapeutic.
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Affiliation(s)
- Stephen W Luckey
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, Campus Box 347, Boulder, Colorado 80309-0347, USA
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Mori S, Gibson G, McTiernan CF. Differential expression of MMPs and TIMPs in moderate and severe heart failure in a transgenic model. J Card Fail 2006; 12:314-25. [PMID: 16679266 DOI: 10.1016/j.cardfail.2006.01.009] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2005] [Revised: 01/07/2006] [Accepted: 01/16/2006] [Indexed: 11/23/2022]
Abstract
BACKGROUND Altered expression of matrix metalloproteinases (MMPs) and their endogenous inhibitors (TIMPs) accompanies the development of heart failure (HF). However, changes in MMP and TIMP protein levels or activity during the progression from compensated to decompensated failure remains incompletely examined. METHODS AND RESULTS Transgenic mice (Tg) with cardiac-specific overexpression of tumor necrosis factor-alpha (TNF1.6) develop a sex-related, progressive cardiac dilation and HF. Echocardiographic measures were used to categorize HF severity in male (M) and female (F) Tg and wild-type (WT) mice between 4 and 50 weeks of age. Cardiac TIMPs-1, TIMPs-2, and MMP-3 (enzyme-linked immunosorbent assay), and potential (APMA-activated) MMP-9 activity were measured at similar ages. In situ zymography assessed tissue gelatinase activity. Systolic function, ventricular dimensions, and presence of pleural effusions identified severe HF in younger M Tg mice (by 18 weeks) and older F Tg (>34 weeks). Regardless of age, sex, or HF severity, Tg mice expressed significantly more TIMP-1 (Tg 119-193 pg/mg vs. WT 13-24 pg/mg, P < .001) and potential MMP-9 activity (Tg 0.41-0.58 ng/mg vs. WT 0.015-0.028 ng/mg, P < .002). M Tg expressed elevated MMP-3 (4 weeks, 0.16 +/- 0.1 ng/mg protein vs. WT 0.04 +/- 0.01 ng/mg, P < .003), which increased with age and HF severity (18 weeks, 0.51 +/- 0.3 ng/mg P < .01). F Tg showed no increase in MMP-3 at 4 weeks but a progressive increase with age and HF severity (18 weeks 0.09 +/- 0.04 ng/mg, P < .02 vs. Tg M or WT; 34 weeks 0.13 +/- 0.02 ng/mg, P < .001 vs. WT). To test the hypothesis that increased MMP-3 may differentially activate MMP-9 in M Tg, in situ zymography was performed and revealed a significant increase in gelatinase activity in M Tg mice relative to both WT and F Tg. CONCLUSION MMP-3 may regulate activation of MMP-9/gelatinase, the progression of cardiac remodeling, and development of decompensated heart failure.
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Affiliation(s)
- Satsuki Mori
- Cardiovascular Institute of the UPMC Health System, University of Pittsburgh, Pennsylvania, USA
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