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Mitronova GY, Quentin C, Belov VN, Wegener JW, Kiszka KA, Lehnart SE. 1,4-Benzothiazepines with Cyclopropanol Groups and Their Structural Analogues Exhibit Both RyR2-Stabilizing and SERCA2a-Stimulating Activities. J Med Chem 2023; 66:15761-15775. [PMID: 37991191 PMCID: PMC10726367 DOI: 10.1021/acs.jmedchem.3c01235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 10/24/2023] [Accepted: 11/07/2023] [Indexed: 11/23/2023]
Abstract
To discover new multifunctional agents for the treatment of cardiovascular diseases, we designed and synthesized a series of compounds with a cyclopropyl alcohol moiety and evaluated them in biochemical assays. Biological screening identified derivatives with dual activity: preventing Ca2+ leak through ryanodine receptor 2 (RyR2) and enhancing cardiac sarco-endoplasmic reticulum (SR) Ca2+ load by activation of Ca2+-dependent ATPase 2a (SERCA2a). The compounds that stabilize RyR2 at micro- and nanomolar concentrations are either structurally related to RyR-stabilizing drugs or Rycals or have structures similar to them. The novel compounds also demonstrate a good ability to increase ATP hydrolysis mediated by SERCA2a activity in cardiac microsomes, e.g., the half-maximal effective concentration (EC50) was as low as 383 nM for compound 12a, which is 1,4-benzothiazepine with two cyclopropanol groups. Our findings indicate that these derivatives can be considered as new lead compounds to improve cardiac function in heart failure.
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Affiliation(s)
- Gyuzel Y. Mitronova
- Department
of NanoBiophotonics, Max Planck Institute
for Multidisciplinary Sciences, Am Fassberg 11, Göttingen 37077, Germany
- German
Centre for Cardiovascular Research (DZHK), Partner Site Göttingen, Göttingen 37075, Germany
| | - Christine Quentin
- Department
of NanoBiophotonics, Max Planck Institute
for Multidisciplinary Sciences, Am Fassberg 11, Göttingen 37077, Germany
| | - Vladimir N. Belov
- Department
of NanoBiophotonics, Max Planck Institute
for Multidisciplinary Sciences, Am Fassberg 11, Göttingen 37077, Germany
| | - Jörg W. Wegener
- Department
of Cardiology & Pulmonology, Heart Research Center Göttingen, University Medical Center Göttingen, Robert-Koch-Strasse 42a, Göttingen 37075, Germany
- German
Centre for Cardiovascular Research (DZHK), Partner Site Göttingen, Göttingen 37075, Germany
| | - Kamila A. Kiszka
- Department
of NanoBiophotonics, Max Planck Institute
for Multidisciplinary Sciences, Am Fassberg 11, Göttingen 37077, Germany
| | - Stephan E. Lehnart
- Department
of Cardiology & Pulmonology, Heart Research Center Göttingen, University Medical Center Göttingen, Robert-Koch-Strasse 42a, Göttingen 37075, Germany
- German
Centre for Cardiovascular Research (DZHK), Partner Site Göttingen, Göttingen 37075, Germany
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2
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Wan JF, Wang G, Qin FY, Huang DL, Wang Y, Su AL, Zhang HP, Liu Y, Zeng SY, Wei CL, Cheng YX, Liu J. Z16b, a natural compound from Ganoderma cochlear is a novel RyR2 stabilizer preventing catecholaminergic polymorphic ventricular tachycardia. Acta Pharmacol Sin 2022; 43:2340-2350. [PMID: 35190699 PMCID: PMC9433431 DOI: 10.1038/s41401-022-00870-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Accepted: 01/17/2022] [Indexed: 01/18/2023] Open
Abstract
Catecholaminergic polymorphic ventricular tachycardia (CPVT) is an inherited, lethal ventricular arrhythmia triggered by catecholamines. Mutations in genes that encode cardiac ryanodine receptor (RyR2) and proteins that regulate RyR2 activity cause enhanced diastolic Ca2+ release (leak) through the RyR2 channels, resulting in CPVT. Current therapies for CPVT are limited. We found that Z16b, a meroterpenoid isolated from Ganoderma cochlear, inhibited Ca2+ spark frequency (CaSF) in R2474S/ + cardiomyocytes in a dose-dependent manner, with an IC50 of 3.2 μM. Z16b also dose-dependently suppressed abnormal post-pacing Ca2+ release events. Intraperitoneal injection (i.p.) of epinephrine and caffeine stimulated sustained ventricular tachycardia in all R2474S/+ mice, while pretreatment with Z16b (0.5 mg/kg, i.p.) prevented ventricular arrhythmia in 9 of 10 mice, and Z16b administration immediately after the onset of VT abolished sVT in 9 of 12 mice. Of translational significance, Z16b significantly inhibited CaSF and abnormal Ca2+ release events in human CPVT iPS-CMs. Mechanistically, Z16b interacts with RyR2, enhancing the "zipping" state of the N-terminal and central domains of RyR2. A molecular docking simulation and point mutation and pulldown assays identified Z16b forms hydrogen bonds with Arg626, His1670, and Gln2126 in RyR2 as a triangle shape that anchors the NTD and CD interaction and thus stabilizes RyR2 in a tight "zipping" conformation. Our findings support that Z16b is a novel RyR2 stabilizer that can prevent CPVT. It may also serve as a lead compound with a new scaffold for the design of safer and more efficient drugs for treating CPVT.
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Affiliation(s)
- Jiang-Fan Wan
- Guangdong Key Laboratory of Genome Stability and Human Disease Prevention, Department of Pathophysiology, School of Medicine, Shenzhen University, Shenzhen, 518000, China
- College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, China
| | - Gang Wang
- Guangdong Key Laboratory of Genome Stability and Human Disease Prevention, Department of Pathophysiology, School of Medicine, Shenzhen University, Shenzhen, 518000, China
| | - Fu-Ying Qin
- School of Pharmaceutical Sciences, Shenzhen University Health Science Center, Shenzhen, 518000, China
| | - Dan-Ling Huang
- School of Pharmaceutical Sciences, Shenzhen University Health Science Center, Shenzhen, 518000, China
| | - Yan Wang
- Center for Translation Medicine Research and Development, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518000, China
| | - Ai-Ling Su
- Center for Translation Medicine Research and Development, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518000, China
| | - Hai-Ping Zhang
- Center for High Performance Computing, Joint Engineering Research Center for Health Big Data Intelligent Analysis Technology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518000, China
| | - Yang Liu
- Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, 510000, China
| | - Shao-Yin Zeng
- Guangdong Provincial key laboratory of South China Structure Heart Disease, Department of Pediatric Cardiology, Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, 510000, China
| | - Chao-Liang Wei
- Guangdong Key Laboratory of Genome Stability and Human Disease Prevention, Department of Pathophysiology, School of Medicine, Shenzhen University, Shenzhen, 518000, China
| | - Yong-Xian Cheng
- School of Pharmaceutical Sciences, Shenzhen University Health Science Center, Shenzhen, 518000, China.
| | - Jie Liu
- Guangdong Key Laboratory of Genome Stability and Human Disease Prevention, Department of Pathophysiology, School of Medicine, Shenzhen University, Shenzhen, 518000, China.
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3
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Amoni M, Dries E, Ingelaere S, Vermoortele D, Roderick HL, Claus P, Willems R, Sipido KR. Ventricular Arrhythmias in Ischemic Cardiomyopathy-New Avenues for Mechanism-Guided Treatment. Cells 2021; 10:2629. [PMID: 34685609 PMCID: PMC8534043 DOI: 10.3390/cells10102629] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 09/20/2021] [Accepted: 09/23/2021] [Indexed: 12/13/2022] Open
Abstract
Ischemic heart disease is the most common cause of lethal ventricular arrhythmias and sudden cardiac death (SCD). In patients who are at high risk after myocardial infarction, implantable cardioverter defibrillators are the most effective treatment to reduce incidence of SCD and ablation therapy can be effective for ventricular arrhythmias with identifiable culprit lesions. Yet, these approaches are not always successful and come with a considerable cost, while pharmacological management is often poor and ineffective, and occasionally proarrhythmic. Advances in mechanistic insights of arrhythmias and technological innovation have led to improved interventional approaches that are being evaluated clinically, yet pharmacological advancement has remained behind. We review the mechanistic basis for current management and provide a perspective for gaining new insights that centre on the complex tissue architecture of the arrhythmogenic infarct and border zone with surviving cardiac myocytes as the source of triggers and central players in re-entry circuits. Identification of the arrhythmia critical sites and characterisation of the molecular signature unique to these sites can open avenues for targeted therapy and reduce off-target effects that have hampered systemic pharmacotherapy. Such advances are in line with precision medicine and a patient-tailored therapy.
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Affiliation(s)
- Matthew Amoni
- Experimental Cardiology, Department of Cardiovascular Sciences, KU Leuven, 3000 Leuven, Belgium; (M.A.); (E.D.); (S.I.); (H.L.R.); (R.W.)
- Division of Cardiology, University Hospitals Leuven, 3000 Leuven, Belgium
- Department of Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town 7935, South Africa
| | - Eef Dries
- Experimental Cardiology, Department of Cardiovascular Sciences, KU Leuven, 3000 Leuven, Belgium; (M.A.); (E.D.); (S.I.); (H.L.R.); (R.W.)
| | - Sebastian Ingelaere
- Experimental Cardiology, Department of Cardiovascular Sciences, KU Leuven, 3000 Leuven, Belgium; (M.A.); (E.D.); (S.I.); (H.L.R.); (R.W.)
- Division of Cardiology, University Hospitals Leuven, 3000 Leuven, Belgium
| | - Dylan Vermoortele
- Imaging and Cardiovascular Dynamics, Department of Cardiovascular Sciences, KU Leuven, 3000 Leuven, Belgium; (D.V.); (P.C.)
| | - H. Llewelyn Roderick
- Experimental Cardiology, Department of Cardiovascular Sciences, KU Leuven, 3000 Leuven, Belgium; (M.A.); (E.D.); (S.I.); (H.L.R.); (R.W.)
| | - Piet Claus
- Imaging and Cardiovascular Dynamics, Department of Cardiovascular Sciences, KU Leuven, 3000 Leuven, Belgium; (D.V.); (P.C.)
| | - Rik Willems
- Experimental Cardiology, Department of Cardiovascular Sciences, KU Leuven, 3000 Leuven, Belgium; (M.A.); (E.D.); (S.I.); (H.L.R.); (R.W.)
- Division of Cardiology, University Hospitals Leuven, 3000 Leuven, Belgium
| | - Karin R. Sipido
- Experimental Cardiology, Department of Cardiovascular Sciences, KU Leuven, 3000 Leuven, Belgium; (M.A.); (E.D.); (S.I.); (H.L.R.); (R.W.)
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4
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The Relationship between Estrogen and Nitric Oxide in the Prevention of Cardiac and Vascular Anomalies in the Developing Zebrafish (Danio Rerio). Brain Sci 2016; 6:brainsci6040051. [PMID: 27792175 PMCID: PMC5187565 DOI: 10.3390/brainsci6040051] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Revised: 10/05/2016] [Accepted: 10/20/2016] [Indexed: 11/16/2022] Open
Abstract
It has been known that both estrogen (E2) and nitric oxide (NO) are critical for proper cardiovascular system (CVS) function. It has also been demonstrated that E2 acts as an upstream effector in the nitric oxide (NO) pathway. Results from this study indicate that the use of a nitric oxide synthase (NOS) inhibitor (NOSI) which targets specifically neuronal NOS (nNOS or NOS1), proadifen hydrochloride, caused a significant depression of fish heart rates (HR) accompanied by increased arrhythmic behavior. However, none of these phenotypes were evident with either the inhibition of endothelial NOS (eNOS) or inducible NOS (iNOS) isoforms. These cardiac arrhythmias could also be mimicked by inhibition of E2 synthesis with the aromatase inhibitor (AI), 4-OH-A, in a manner similar to that of nNOSI. In both scenarios, by using an NO donor (DETA-NO) in either NO + nNOSI or E2 + AI co-treatments, fish could be significantly rescued from decreased HR and increased arrhythmias. However, the addition of an NOS inhibitor (L-NAME) to the E2 + AI co-treatment fish prevented the rescue of low heart rates and arrhythmias, which strongly implicates the NO pathway as a downstream E2 targeted molecule for the maintenance of healthy cardiomyocyte contractile conditions in the developing zebrafish. Cardiac arrhythmias could be mimicked by the S-nitrosylation pathway inhibitor DTT (1,4-dithiothreitol) but not by ODQ (1H-[1–3]oxadiazolo[4,3-a]quinoxalin-1-one), the inhibitor of the NO receptor molecule sGC in the cGMP-dependent pathway. In both the nNOSI and AI-induced arrhythmic conditions, 100% of the fish expressed the phenotype, but could be rapidly rescued with maximum survival by a washout with dantrolene, a ryanodine Ca2+ channel receptor blocker, compared to the time it took for rescue using a control salt solution. In addition, of the three NOS isoforms, eNOS was the one most implicated in the maintenance of an intact developing fish vascular system. In conclusion, results from this study have shown that nNOS is the prominent isoform that is responsible, in part, for maintaining normal heart rates and prevention of arrhythmias in the developing zebrafish heart failure model. These phenomena are related to the upstream stimulatory regulation by E2. On the other hand, eNOS has a minimal effect and iNOS has little to no influence on this phenomenon. Data also suggests that nNOS acts on the zebrafish cardiomyocytes through the S-nitrosylation pathway to influence the SR ryanidine Ca2+ channels in the excitation-coupling phenomena. In contrast, eNOS is the prominent isoform that influences blood vessel development in this model.
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5
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De Ferrari GM, Dusi V, Spazzolini C, Bos JM, Abrams DJ, Berul CI, Crotti L, Davis AM, Eldar M, Kharlap M, Khoury A, Krahn AD, Leenhardt A, Moir CR, Odero A, Olde Nordkamp L, Paul T, Rosés i Noguer F, Shkolnikova M, Till J, Wilde AA, Ackerman MJ, Schwartz PJ. Clinical Management of Catecholaminergic Polymorphic Ventricular Tachycardia. Circulation 2015; 131:2185-93. [DOI: 10.1161/circulationaha.115.015731] [Citation(s) in RCA: 204] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Accepted: 04/21/2015] [Indexed: 11/16/2022]
Abstract
Background—
Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a genetic disorder causing life-threatening arrhythmias whenever sympathetic activity increases. β-Βlockers are the mainstay of therapy; when they fail, implantable cardioverter-defibrillators (ICDs) are used but often cause multiple shocks. Preliminary results with flecainide appear encouraging. We proposed left cardiac sympathetic denervation (LCSD) as useful additional therapy, but evidence remains anecdotal.
Methods and Results—
We report 63 patients with CPVT who underwent LCSD as secondary (n=54) or primary (n=9) prevention. The median post-LCSD follow-up was 37 months. The 9 asymptomatic patients remained free of major cardiac events. Of the 54 patients with prior major cardiac events either on (n=38) or off (n=16) optimal medical therapy, 13 (24%) had at least 1 recurrence: 0 patients had an aborted cardiac arrest, 2 patients had syncope only, 10 patients had ≥1 appropriate ICD discharges, and 1 patient died suddenly. The 1- and 2-year cumulative event-free survival rates were 87% and 81%. The percentage of patients with major cardiac events despite optimal medical therapy (n=38) was reduced from 100% to 32% (
P
<0.001) after LCSD, and among 29 patients with a presurgical ICD, the rate of shocks dropped by 93% from 3.6 to 0.6 shocks per person per year (
P
<0.001). Patients with an incomplete LCSD (n=7) were more likely to experience major cardiac events after LCSD (71% versus 17%;
P
<0.01) than those with a complete LCSD.
Conclusions—
LCSD is an effective antifibrillatory intervention for patients with CPVT. Whenever syncope occurs despite optimal medical therapy, LCSD could be considered the next step rather than an ICD and could complement ICDs in patients with recurrent shocks.
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Affiliation(s)
- Gaetano M. De Ferrari
- From Department of Cardiology and Cardiovascular Clinical Research Center (G.M.D.F., V.D.) and Division of Vascular Surgery (A.O.), Fondazione IRCCS Policlinico San Matteo, Pavia, Italy; Department of Molecular Medicine, University of Pavia, Italy (G.M.D.T., V.D., C.S., L.C.); Center for Cardiac Arrhythmias of Genetic Origin, IRCCS Istituto Auxologico Italiano, Milano, Italy (C.S., L.C., P.J.S.); Departments of Medicine, Pediatrics, and Molecular Pharmacology & Experimental Therapeutics,
| | - Veronica Dusi
- From Department of Cardiology and Cardiovascular Clinical Research Center (G.M.D.F., V.D.) and Division of Vascular Surgery (A.O.), Fondazione IRCCS Policlinico San Matteo, Pavia, Italy; Department of Molecular Medicine, University of Pavia, Italy (G.M.D.T., V.D., C.S., L.C.); Center for Cardiac Arrhythmias of Genetic Origin, IRCCS Istituto Auxologico Italiano, Milano, Italy (C.S., L.C., P.J.S.); Departments of Medicine, Pediatrics, and Molecular Pharmacology & Experimental Therapeutics,
| | - Carla Spazzolini
- From Department of Cardiology and Cardiovascular Clinical Research Center (G.M.D.F., V.D.) and Division of Vascular Surgery (A.O.), Fondazione IRCCS Policlinico San Matteo, Pavia, Italy; Department of Molecular Medicine, University of Pavia, Italy (G.M.D.T., V.D., C.S., L.C.); Center for Cardiac Arrhythmias of Genetic Origin, IRCCS Istituto Auxologico Italiano, Milano, Italy (C.S., L.C., P.J.S.); Departments of Medicine, Pediatrics, and Molecular Pharmacology & Experimental Therapeutics,
| | - J. Martijn Bos
- From Department of Cardiology and Cardiovascular Clinical Research Center (G.M.D.F., V.D.) and Division of Vascular Surgery (A.O.), Fondazione IRCCS Policlinico San Matteo, Pavia, Italy; Department of Molecular Medicine, University of Pavia, Italy (G.M.D.T., V.D., C.S., L.C.); Center for Cardiac Arrhythmias of Genetic Origin, IRCCS Istituto Auxologico Italiano, Milano, Italy (C.S., L.C., P.J.S.); Departments of Medicine, Pediatrics, and Molecular Pharmacology & Experimental Therapeutics,
| | - Dominic J. Abrams
- From Department of Cardiology and Cardiovascular Clinical Research Center (G.M.D.F., V.D.) and Division of Vascular Surgery (A.O.), Fondazione IRCCS Policlinico San Matteo, Pavia, Italy; Department of Molecular Medicine, University of Pavia, Italy (G.M.D.T., V.D., C.S., L.C.); Center for Cardiac Arrhythmias of Genetic Origin, IRCCS Istituto Auxologico Italiano, Milano, Italy (C.S., L.C., P.J.S.); Departments of Medicine, Pediatrics, and Molecular Pharmacology & Experimental Therapeutics,
| | - Charles I. Berul
- From Department of Cardiology and Cardiovascular Clinical Research Center (G.M.D.F., V.D.) and Division of Vascular Surgery (A.O.), Fondazione IRCCS Policlinico San Matteo, Pavia, Italy; Department of Molecular Medicine, University of Pavia, Italy (G.M.D.T., V.D., C.S., L.C.); Center for Cardiac Arrhythmias of Genetic Origin, IRCCS Istituto Auxologico Italiano, Milano, Italy (C.S., L.C., P.J.S.); Departments of Medicine, Pediatrics, and Molecular Pharmacology & Experimental Therapeutics,
| | - Lia Crotti
- From Department of Cardiology and Cardiovascular Clinical Research Center (G.M.D.F., V.D.) and Division of Vascular Surgery (A.O.), Fondazione IRCCS Policlinico San Matteo, Pavia, Italy; Department of Molecular Medicine, University of Pavia, Italy (G.M.D.T., V.D., C.S., L.C.); Center for Cardiac Arrhythmias of Genetic Origin, IRCCS Istituto Auxologico Italiano, Milano, Italy (C.S., L.C., P.J.S.); Departments of Medicine, Pediatrics, and Molecular Pharmacology & Experimental Therapeutics,
| | - Andrew M. Davis
- From Department of Cardiology and Cardiovascular Clinical Research Center (G.M.D.F., V.D.) and Division of Vascular Surgery (A.O.), Fondazione IRCCS Policlinico San Matteo, Pavia, Italy; Department of Molecular Medicine, University of Pavia, Italy (G.M.D.T., V.D., C.S., L.C.); Center for Cardiac Arrhythmias of Genetic Origin, IRCCS Istituto Auxologico Italiano, Milano, Italy (C.S., L.C., P.J.S.); Departments of Medicine, Pediatrics, and Molecular Pharmacology & Experimental Therapeutics,
| | - Michael Eldar
- From Department of Cardiology and Cardiovascular Clinical Research Center (G.M.D.F., V.D.) and Division of Vascular Surgery (A.O.), Fondazione IRCCS Policlinico San Matteo, Pavia, Italy; Department of Molecular Medicine, University of Pavia, Italy (G.M.D.T., V.D., C.S., L.C.); Center for Cardiac Arrhythmias of Genetic Origin, IRCCS Istituto Auxologico Italiano, Milano, Italy (C.S., L.C., P.J.S.); Departments of Medicine, Pediatrics, and Molecular Pharmacology & Experimental Therapeutics,
| | - Maria Kharlap
- From Department of Cardiology and Cardiovascular Clinical Research Center (G.M.D.F., V.D.) and Division of Vascular Surgery (A.O.), Fondazione IRCCS Policlinico San Matteo, Pavia, Italy; Department of Molecular Medicine, University of Pavia, Italy (G.M.D.T., V.D., C.S., L.C.); Center for Cardiac Arrhythmias of Genetic Origin, IRCCS Istituto Auxologico Italiano, Milano, Italy (C.S., L.C., P.J.S.); Departments of Medicine, Pediatrics, and Molecular Pharmacology & Experimental Therapeutics,
| | - Asaad Khoury
- From Department of Cardiology and Cardiovascular Clinical Research Center (G.M.D.F., V.D.) and Division of Vascular Surgery (A.O.), Fondazione IRCCS Policlinico San Matteo, Pavia, Italy; Department of Molecular Medicine, University of Pavia, Italy (G.M.D.T., V.D., C.S., L.C.); Center for Cardiac Arrhythmias of Genetic Origin, IRCCS Istituto Auxologico Italiano, Milano, Italy (C.S., L.C., P.J.S.); Departments of Medicine, Pediatrics, and Molecular Pharmacology & Experimental Therapeutics,
| | - Andrew D. Krahn
- From Department of Cardiology and Cardiovascular Clinical Research Center (G.M.D.F., V.D.) and Division of Vascular Surgery (A.O.), Fondazione IRCCS Policlinico San Matteo, Pavia, Italy; Department of Molecular Medicine, University of Pavia, Italy (G.M.D.T., V.D., C.S., L.C.); Center for Cardiac Arrhythmias of Genetic Origin, IRCCS Istituto Auxologico Italiano, Milano, Italy (C.S., L.C., P.J.S.); Departments of Medicine, Pediatrics, and Molecular Pharmacology & Experimental Therapeutics,
| | - Antoine Leenhardt
- From Department of Cardiology and Cardiovascular Clinical Research Center (G.M.D.F., V.D.) and Division of Vascular Surgery (A.O.), Fondazione IRCCS Policlinico San Matteo, Pavia, Italy; Department of Molecular Medicine, University of Pavia, Italy (G.M.D.T., V.D., C.S., L.C.); Center for Cardiac Arrhythmias of Genetic Origin, IRCCS Istituto Auxologico Italiano, Milano, Italy (C.S., L.C., P.J.S.); Departments of Medicine, Pediatrics, and Molecular Pharmacology & Experimental Therapeutics,
| | - Christopher R. Moir
- From Department of Cardiology and Cardiovascular Clinical Research Center (G.M.D.F., V.D.) and Division of Vascular Surgery (A.O.), Fondazione IRCCS Policlinico San Matteo, Pavia, Italy; Department of Molecular Medicine, University of Pavia, Italy (G.M.D.T., V.D., C.S., L.C.); Center for Cardiac Arrhythmias of Genetic Origin, IRCCS Istituto Auxologico Italiano, Milano, Italy (C.S., L.C., P.J.S.); Departments of Medicine, Pediatrics, and Molecular Pharmacology & Experimental Therapeutics,
| | - Attilio Odero
- From Department of Cardiology and Cardiovascular Clinical Research Center (G.M.D.F., V.D.) and Division of Vascular Surgery (A.O.), Fondazione IRCCS Policlinico San Matteo, Pavia, Italy; Department of Molecular Medicine, University of Pavia, Italy (G.M.D.T., V.D., C.S., L.C.); Center for Cardiac Arrhythmias of Genetic Origin, IRCCS Istituto Auxologico Italiano, Milano, Italy (C.S., L.C., P.J.S.); Departments of Medicine, Pediatrics, and Molecular Pharmacology & Experimental Therapeutics,
| | - Louise Olde Nordkamp
- From Department of Cardiology and Cardiovascular Clinical Research Center (G.M.D.F., V.D.) and Division of Vascular Surgery (A.O.), Fondazione IRCCS Policlinico San Matteo, Pavia, Italy; Department of Molecular Medicine, University of Pavia, Italy (G.M.D.T., V.D., C.S., L.C.); Center for Cardiac Arrhythmias of Genetic Origin, IRCCS Istituto Auxologico Italiano, Milano, Italy (C.S., L.C., P.J.S.); Departments of Medicine, Pediatrics, and Molecular Pharmacology & Experimental Therapeutics,
| | - Thomas Paul
- From Department of Cardiology and Cardiovascular Clinical Research Center (G.M.D.F., V.D.) and Division of Vascular Surgery (A.O.), Fondazione IRCCS Policlinico San Matteo, Pavia, Italy; Department of Molecular Medicine, University of Pavia, Italy (G.M.D.T., V.D., C.S., L.C.); Center for Cardiac Arrhythmias of Genetic Origin, IRCCS Istituto Auxologico Italiano, Milano, Italy (C.S., L.C., P.J.S.); Departments of Medicine, Pediatrics, and Molecular Pharmacology & Experimental Therapeutics,
| | - Ferran Rosés i Noguer
- From Department of Cardiology and Cardiovascular Clinical Research Center (G.M.D.F., V.D.) and Division of Vascular Surgery (A.O.), Fondazione IRCCS Policlinico San Matteo, Pavia, Italy; Department of Molecular Medicine, University of Pavia, Italy (G.M.D.T., V.D., C.S., L.C.); Center for Cardiac Arrhythmias of Genetic Origin, IRCCS Istituto Auxologico Italiano, Milano, Italy (C.S., L.C., P.J.S.); Departments of Medicine, Pediatrics, and Molecular Pharmacology & Experimental Therapeutics,
| | - Maria Shkolnikova
- From Department of Cardiology and Cardiovascular Clinical Research Center (G.M.D.F., V.D.) and Division of Vascular Surgery (A.O.), Fondazione IRCCS Policlinico San Matteo, Pavia, Italy; Department of Molecular Medicine, University of Pavia, Italy (G.M.D.T., V.D., C.S., L.C.); Center for Cardiac Arrhythmias of Genetic Origin, IRCCS Istituto Auxologico Italiano, Milano, Italy (C.S., L.C., P.J.S.); Departments of Medicine, Pediatrics, and Molecular Pharmacology & Experimental Therapeutics,
| | - Jan Till
- From Department of Cardiology and Cardiovascular Clinical Research Center (G.M.D.F., V.D.) and Division of Vascular Surgery (A.O.), Fondazione IRCCS Policlinico San Matteo, Pavia, Italy; Department of Molecular Medicine, University of Pavia, Italy (G.M.D.T., V.D., C.S., L.C.); Center for Cardiac Arrhythmias of Genetic Origin, IRCCS Istituto Auxologico Italiano, Milano, Italy (C.S., L.C., P.J.S.); Departments of Medicine, Pediatrics, and Molecular Pharmacology & Experimental Therapeutics,
| | - Arthur A.M. Wilde
- From Department of Cardiology and Cardiovascular Clinical Research Center (G.M.D.F., V.D.) and Division of Vascular Surgery (A.O.), Fondazione IRCCS Policlinico San Matteo, Pavia, Italy; Department of Molecular Medicine, University of Pavia, Italy (G.M.D.T., V.D., C.S., L.C.); Center for Cardiac Arrhythmias of Genetic Origin, IRCCS Istituto Auxologico Italiano, Milano, Italy (C.S., L.C., P.J.S.); Departments of Medicine, Pediatrics, and Molecular Pharmacology & Experimental Therapeutics,
| | - Michael J. Ackerman
- From Department of Cardiology and Cardiovascular Clinical Research Center (G.M.D.F., V.D.) and Division of Vascular Surgery (A.O.), Fondazione IRCCS Policlinico San Matteo, Pavia, Italy; Department of Molecular Medicine, University of Pavia, Italy (G.M.D.T., V.D., C.S., L.C.); Center for Cardiac Arrhythmias of Genetic Origin, IRCCS Istituto Auxologico Italiano, Milano, Italy (C.S., L.C., P.J.S.); Departments of Medicine, Pediatrics, and Molecular Pharmacology & Experimental Therapeutics,
| | - Peter J. Schwartz
- From Department of Cardiology and Cardiovascular Clinical Research Center (G.M.D.F., V.D.) and Division of Vascular Surgery (A.O.), Fondazione IRCCS Policlinico San Matteo, Pavia, Italy; Department of Molecular Medicine, University of Pavia, Italy (G.M.D.T., V.D., C.S., L.C.); Center for Cardiac Arrhythmias of Genetic Origin, IRCCS Istituto Auxologico Italiano, Milano, Italy (C.S., L.C., P.J.S.); Departments of Medicine, Pediatrics, and Molecular Pharmacology & Experimental Therapeutics,
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6
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Walweel K, Laver DR. Mechanisms of SR calcium release in healthy and failing human hearts. Biophys Rev 2015; 7:33-41. [PMID: 28509976 PMCID: PMC5425750 DOI: 10.1007/s12551-014-0152-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Accepted: 11/25/2014] [Indexed: 01/08/2023] Open
Abstract
Normal heart contraction and rhythm relies on the proper flow of calcium ions (Ca2+) into cardiac cells and between their intracellular organelles, and any disruption can lead to arrhythmia and sudden cardiac death. Electrical excitation of the surface membrane activates voltage-dependent L-type Ca2+ channels to open and allow Ca2+ to enter the cytoplasm. The subsequent increase in cytoplasmic Ca2+ concentration activates calcium release channels (RyR2) located at specialised Ca2+ release sites in the sarcoplasmic reticulum (SR), which serves as an intracellular Ca2+ store. Animal models have provided valuable insights into how intracellular Ca2+ transport mechanisms are altered in human heart failure. The aim of this review is to examine how Ca2+ release sites are remodelled in heart failure and how this affects intracellular Ca2+ transport with an emphasis on Ca2+ release mechanisms in the SR. Current knowledge on how heart failure alters the regulation of RyR2 by Ca2+ and Mg2+ and how these mechanisms control the activity of RyR2 in the confines of the Ca2+ release sites is reviewed.
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Affiliation(s)
- K Walweel
- School of Biomedical Sciences and Pharmacy, University of Newcastle and Hunter Medical Research Institute, Callaghan, NSW, 2308, Australia
| | - D R Laver
- School of Biomedical Sciences and Pharmacy, University of Newcastle and Hunter Medical Research Institute, Callaghan, NSW, 2308, Australia.
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7
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Dobrev D, Wehrens XHT. Role of RyR2 phosphorylation in heart failure and arrhythmias: Controversies around ryanodine receptor phosphorylation in cardiac disease. Circ Res 2014; 114:1311-9; discussion 1319. [PMID: 24723656 DOI: 10.1161/circresaha.114.300568] [Citation(s) in RCA: 131] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Cardiac ryanodine receptor type 2 plays a key role in excitation-contraction coupling. The ryanodine receptor type 2 channel protein is modulated by various post-translational modifications, including phosphorylation by protein kinase A and Ca(2+)/calmodulin protein kinase II. Despite extensive research in this area, the functional effects of ryanodine receptor type 2 phosphorylation remain disputed. In particular, the potential involvement of increased ryanodine receptor type 2 phosphorylation in the pathogenesis of heart failure and arrhythmias remains a controversial area, which is discussed in this review article.
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Affiliation(s)
- Dobromir Dobrev
- From the Institute of Pharmacology, Faculty of Medicine, University Duisburg-Essen, Essen, Germany (D.D.); and Cardiovascular Research Institute, Departments of Molecular Physiology and Biophysics, and Medicine-Cardiology, Baylor College of Medicine, Houston, TX (X.H.T.W.)
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8
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Liu Z, Cai H, Zhu H, Toque H, Zhao N, Qiu C, Guan G, Dang Y, Wang J. Protein kinase RNA-like endoplasmic reticulum kinase (PERK)/calcineurin signaling is a novel pathway regulating intracellular calcium accumulation which might be involved in ventricular arrhythmias in diabetic cardiomyopathy. Cell Signal 2014; 26:2591-600. [PMID: 25152364 DOI: 10.1016/j.cellsig.2014.08.015] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Accepted: 08/17/2014] [Indexed: 11/18/2022]
Abstract
We previously found that endoplasmic reticulum (ER) stress was involved in ventricular arrhythmias in diabetic cardiomyopathy. The present study was aimed to investigate the possible mechanism. In the in vivo study, diabetes cardiomyopathy (DCM) was induced by streptozotocin (STZ) injection. Hemodynamic and plasma brain natriuretic peptide (BNP) detections were used to evaluate cardiac functions; ECG was used to assess the vulnerability to arrhythmias by recording ventricular arrhythmia events (VAEs). In the in vitro study, high-glucose incubation was employed to mimic the diabetic environment of myocytes. Immunofluorescent staining was used to investigate the nuclear factor of activated T cells (NFAT) nuclear translocation and (FK506-binding protein 12.6) FKBP12.6 disassociation. [(3)H]-ryanodine binding assay was implemented to assess the channel activity of ryanodine receptor. In both in vivo and in vitro studies, activity of calcineurin was determined by colorimetric method, and western blotting was used to detect protein expression levels. In the in vivo study, we found that inhibition of both of ER stress and PERK activation decreased the VAEs in DCM rats, accompanied by reduced activity of calcineurin in myocardial tissue. In the in vitro study, in high-glucose incubated myocytes, the depletion of PERK reduced activity of calcineurin, decreased NFAT translocation and FKBP12.6 disassociation from ryanodine receptor 2 (RyR2). Furthermore, PERK deletion also reduced RyR2 channel activity and consequently impaired intracellular calcium accumulation. We concluded that PERK/calcineurin-pathway was involved in intracellular calcium regulation in myocytes in diabetic heart, which might be the mechanism inducing arrhythmias in DCM.
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Affiliation(s)
- Zhongwei Liu
- Department of Cardiology, Shaanxi Provincial People's Hospital, China
| | - Hui Cai
- Department of Anesthesiology, First Affiliated Hospital of Xi'an Jiaotong University, China
| | - Haitao Zhu
- School of Medicine, Xi'an Jiaotong University, China
| | - Haroldo Toque
- Department of Pharmacology and Toxicology, GA Regents University, USA
| | - Na Zhao
- Department of Cardiology, Shaanxi Provincial People's Hospital, China
| | - Chuan Qiu
- School of Public Health & Tropical Medicine, Tulane University, USA
| | - Gongchang Guan
- Department of Cardiology, Shaanxi Provincial People's Hospital, China
| | - Yonghui Dang
- Department of Forensic Science, Xi'an Jiaotong University School of Medicine, China.
| | - Junkui Wang
- Department of Cardiology, Shaanxi Provincial People's Hospital, China.
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9
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Wang L, Myles RC, De Jesus NM, Ohlendorf AKP, Bers DM, Ripplinger CM. Optical mapping of sarcoplasmic reticulum Ca2+ in the intact heart: ryanodine receptor refractoriness during alternans and fibrillation. Circ Res 2014; 114:1410-21. [PMID: 24568740 DOI: 10.1161/circresaha.114.302505] [Citation(s) in RCA: 104] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
RATIONALE Sarcoplasmic reticulum (SR) Ca(2+) cycling is key to normal excitation-contraction coupling but may also contribute to pathological cardiac alternans and arrhythmia. OBJECTIVE To measure intra-SR free [Ca(2+)] ([Ca(2+)]SR) changes in intact hearts during alternans and ventricular fibrillation (VF). METHODS AND RESULTS Simultaneous optical mapping of Vm (with RH237) and [Ca(2+)]SR (with Fluo-5N AM) was performed in Langendorff-perfused rabbit hearts. Alternans and VF were induced by rapid pacing. SR Ca(2+) and action potential duration (APD) alternans occurred in-phase, but SR Ca(2+) alternans emerged first as cycle length was progressively reduced (217±10 versus 190±13 ms; P<0.05). Ryanodine receptor (RyR) refractoriness played a key role in the onset of SR Ca(2+) alternans, with SR Ca(2+) release alternans routinely occurring without changes in diastolic [Ca(2+)]SR. Sensitizing RyR with caffeine (200 μmol/L) significantly reduced the pacing threshold for both SR Ca(2+) and APD alternans (188±15 and 173±12 ms; P<0.05 versus baseline). Caffeine also reduced the magnitude of spatially discordant SR Ca(2+) alternans, but not APD alternans, the pacing threshold for discordance, or threshold for VF. During VF, [Ca(2+)]SR was high, but RyR remained nearly continuously refractory, resulting in minimal SR Ca(2+) release throughout VF. CONCLUSIONS In intact hearts, RyR refractoriness initiates SR Ca(2+) release alternans that can be amplified by diastolic [Ca(2+)]SR alternans and lead to APD alternans. Sensitizing RyR suppresses spatially concordant but not discordant SR Ca(2+) and APD alternans. Despite increased [Ca(2+)]SR during VF, SR Ca(2+) release was nearly continuously refractory. This novel method provides insight into SR Ca(2+) handling during cardiac alternans and arrhythmia.
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Affiliation(s)
- Lianguo Wang
- From the Department of Pharmacology, School of Medicine, University of California, Davis (L.W., N.M.D.J., A.K.P.O., D.M.B., C.M.R.); and Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (R.C.M.)
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10
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Morimoto S, Hongo K, Kusakari Y, Komukai K, Kawai M, O-Uchi J, Nakayama H, Asahi M, Otsu K, Yoshimura M, Kurihara S. Genetic modulation of the SERCA activity does not affect the Ca(2+) leak from the cardiac sarcoplasmic reticulum. Cell Calcium 2013; 55:17-23. [PMID: 24290743 DOI: 10.1016/j.ceca.2013.10.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2013] [Revised: 10/25/2013] [Accepted: 10/28/2013] [Indexed: 10/26/2022]
Abstract
The Ca(2+) content in the sarcoplasmic reticulum (SR) determines the amount of Ca(2+) released, thereby regulating the magnitude of Ca(2+) transient and contraction in cardiac muscle. The Ca(2+) content in the SR is known to be regulated by two factors: the activity of the Ca(2+) pump (SERCA) and Ca(2+) leak through the ryanodine receptor (RyR). However, the direct relationship between the SERCA activity and Ca(2+) leak has not been fully investigated in the heart. In the present study, we evaluated the role of the SERCA activity in Ca(2+) leak from the SR using a novel saponin-skinned method combined with transgenic mouse models in which the SERCA activity was genetically modulated. In the SERCA overexpression mice, the Ca(2+) uptake in the SR was significantly increased and the Ca(2+) transient was markedly increased. However, Ca(2+) leak from the SR did not change significantly. In mice with overexpression of a negative regulator of SERCA, sarcolipin, the Ca(2+) uptake by the SR was significantly decreased and the Ca(2+) transient was markedly decreased. Again, Ca(2+) leak from the SR did not change significantly. In conclusion, the selective modulation of the SERCA activity modulates Ca(2+) uptake, although it does not change Ca(2+) leak from the SR.
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Affiliation(s)
- Satoshi Morimoto
- Division of Cardiology, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan
| | - Kenichi Hongo
- Division of Cardiology, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan.
| | - Yoichiro Kusakari
- Department of Cell Physiology, The Jikei University School of Medicine, Tokyo, Japan
| | - Kimiaki Komukai
- Division of Cardiology, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan
| | - Makoto Kawai
- Division of Cardiology, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan
| | - Jin O-Uchi
- Center for Translational Medicine, Department of Medicine, Jefferson Medical College, Thomas Jefferson University, Philadelphia, USA
| | - Hiroyuki Nakayama
- Department of Clinical Pharmacology and Pharmacogenomics, Graduate School of Pharmaceutical Sciences, Osaka University, Osaka, Japan
| | - Michio Asahi
- Department of Pharmacology, Faculty of Medicine, Osaka Medical College, Osaka, Japan
| | - Kinya Otsu
- Cardiovascular Division, King's College London, London, United Kingdom
| | - Michihiro Yoshimura
- Division of Cardiology, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan
| | - Satoshi Kurihara
- Department of Cell Physiology, The Jikei University School of Medicine, Tokyo, Japan
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11
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Li N, Wehrens XHT. Extinguishing intracellular calcium leak: a promising antiarrhythmic approach. Heart Rhythm 2012; 10:108-9. [PMID: 23085093 DOI: 10.1016/j.hrthm.2012.10.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2012] [Indexed: 01/12/2023]
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12
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Thevis M, Schänzer W. Illicit organogenesis: Methods and substances of doping and manipulation. Organogenesis 2012; 4:264-71. [PMID: 19337407 DOI: 10.4161/org.4.4.7286] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2008] [Accepted: 10/29/2008] [Indexed: 01/12/2023] Open
Abstract
Doping and manipulation are undesirable companions of professional and amateur sport. Numerous adverse analytical findings as well as confessions of athletes have demonstrated the variety of doping agents and methods as well as the inventiveness of cheating sportsmen. Besides 'conventional' misuse of drugs such as erythropoietin and insulins, experts fear that therapeutics that are currently undergoing clinical trials might be part of current or future doping regimens, which aim for an increased functionality and performance or organs and tissues. Emerging drugs such as selective androgen receptor modulators (SARMs), hypoxia-inducible factor (HIF) complex stabilizers or modulators of muscle fiber calcium channels are considered relevant for current and future doping controls due to their high potential for misuse in sports.
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Affiliation(s)
- Mario Thevis
- Center for Preventive Doping Research; Institute of Biochemistry; German Sport University Cologne; Cologne Germany
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13
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Belcher SM, Chen Y, Yan S, Wang HS. Rapid estrogen receptor-mediated mechanisms determine the sexually dimorphic sensitivity of ventricular myocytes to 17β-estradiol and the environmental endocrine disruptor bisphenol A. Endocrinology 2012; 153:712-20. [PMID: 22166976 PMCID: PMC3275382 DOI: 10.1210/en.2011-1772] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Previously we showed that 17β-estradiol (E(2)) and/or the xenoestrogen bisphenol A (BPA) alter ventricular myocyte Ca(2+) handing, resulting in increased cardiac arrhythmias in a female-specific manner. In the present study, the roles of estrogen receptors (ER) in mediating the rapid contractile and arrhythmogenic effects of estrogens were examined. Contractility was used as an index to assess the impact of E(2) or BPA on Ca(2+) handling in rodent ventricular myocytes. The concentration-response curve for the stimulatory effects of BPA and E(2) on female myocyte was inverted-U shaped. Detectable effects for each compound were observed at 10(-12) M, and the most efficacious concentrations for each were at 10(-9) M. Sensitivity to E(2) and BPA was not observed in male myocytes and was abolished in myocytes from ovariectomized females. Analysis using protein-conjugated E(2) suggests that these rapid actions are induced by membrane-associated receptors. Analysis using selective ER agonists and antagonists and a genetic ERβ knockout mouse model showed that ERα and ERβ have opposing actions in myocytes and that the balance between ERβ and ERα signaling is the prime regulator of the sex-specific sensitivity toward estrogens. The response of female myocytes to E(2) and BPA is dominated by the stimulatory ERβ-mediated signaling, and the absence of BPA and E(2) responsiveness in males is due to a counterbalancing-suppressive action of ERα. We conclude that the sex-specific sensitivity of myocytes to estrogens and the rapid arrhythmogenic effects of BPA and estradiol in the female heart are regulated by the balance between ERα and ERβ signaling.
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Affiliation(s)
- Scott M Belcher
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267-0575, USA
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14
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Pinto JR, Siegfried JD, Parvatiyar MS, Li D, Norton N, Jones MA, Liang J, Potter JD, Hershberger RE. Functional characterization of TNNC1 rare variants identified in dilated cardiomyopathy. J Biol Chem 2011; 286:34404-12. [PMID: 21832052 PMCID: PMC3190822 DOI: 10.1074/jbc.m111.267211] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2011] [Revised: 07/12/2011] [Indexed: 11/06/2022] Open
Abstract
TNNC1, which encodes cardiac troponin C (cTnC), remains elusive as a dilated cardiomyopathy (DCM) gene. Here, we report the clinical, genetic, and functional characterization of four TNNC1 rare variants (Y5H, M103I, D145E, and I148V), all previously reported by us in association with DCM (Hershberger, R. E., Norton, N., Morales, A., Li, D., Siegfried, J. D., and Gonzalez-Quintana, J. (2010) Circ. Cardiovasc. Genet. 3, 155-161); in the previous study, two variants (Y5H and D145E) were identified in subjects who also carried MYH7 and MYBPC3 rare variants, respectively. Functional studies using the recombinant human mutant cTnC proteins reconstituted into porcine papillary skinned fibers showed decreased Ca(2+) sensitivity of force development (Y5H and M103I). Furthermore, the cTnC mutants diminished (Y5H and I148V) or abolished (M103I) the effects of PKA phosphorylation on Ca(2+) sensitivity. Only M103I decreased the troponin activation properties of the actomyosin ATPase when Ca(2+) was present. CD spectroscopic studies of apo (absence of divalent cations)-, Mg(2+)-, and Ca(2+)/Mg(2+)-bound states indicated that all of the cTnC mutants (except I148V in the Ca(2+)/Mg(2+) condition) decreased the α-helical content. These results suggest that each mutation alters the function/ability of the myofilament to bind Ca(2+) as a result of modifications in cTnC structure. One variant (D145E) that was previously reported in association with hypertrophic cardiomyopathy and that produced results in vivo in this study consistent with prior hypertrophic cardiomyopathy functional studies was found associated with the MYBPC3 P910T rare variant, likely contributing to the observed DCM phenotype. We conclude that these rare variants alter the regulation of contraction in some way, and the combined clinical, molecular, genetic, and functional data reinforce the importance of TNNC1 rare variants in the pathogenesis of DCM.
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Affiliation(s)
| | - Jill D. Siegfried
- Cardiovascular Division, Department of Medicine, University of Miami Miller School of Medicine, Miami, Florida 33136
| | | | - Duanxiang Li
- Cardiovascular Division, Department of Medicine, University of Miami Miller School of Medicine, Miami, Florida 33136
| | - Nadine Norton
- Cardiovascular Division, Department of Medicine, University of Miami Miller School of Medicine, Miami, Florida 33136
| | | | - Jingsheng Liang
- From the Department of Molecular and Cellular Pharmacology and
| | - James D. Potter
- From the Department of Molecular and Cellular Pharmacology and
| | - Ray E. Hershberger
- Cardiovascular Division, Department of Medicine, University of Miami Miller School of Medicine, Miami, Florida 33136
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15
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Yan S, Chen Y, Dong M, Song W, Belcher SM, Wang HS. Bisphenol A and 17β-estradiol promote arrhythmia in the female heart via alteration of calcium handling. PLoS One 2011; 6:e25455. [PMID: 21980463 PMCID: PMC3181279 DOI: 10.1371/journal.pone.0025455] [Citation(s) in RCA: 114] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2011] [Accepted: 09/05/2011] [Indexed: 12/25/2022] Open
Abstract
Background There is wide-spread human exposure to bisphenol A (BPA), a ubiquitous estrogenic endocrine disruptor that has been implicated as having potentially harmful effects on human heart health. Higher urine BPA concentrations have been shown to be associated with cardiovascular diseases in humans. However, neither the nature nor the mechanism(s) of BPA action on the heart are understood. Methodology/Principal Findings The rapid (<7 min) effects of BPA and 17β-estradiol (E2) in the heart and ventricular myocytes from rodents were investigated in the present study. In isolated ventricular myocytes from young adult females, but not males, physiological concentrations of BPA or E2 (10−9 M) rapidly induced arrhythmogenic triggered activities. The effects of BPA were particularly pronounced when combined with estradiol. Under conditions of catecholamine stimulation, E2 and BPA promoted ventricular arrhythmias in female, but not male, hearts. The cellular mechanism of the female-specific pro-arrhythmic effects of BPA and E2 were investigated. Exposure to E2 and/or BPA rapidly altered myocyte Ca2+ handling; in particular, estrogens markedly increased sarcoplasmic reticulum (SR) Ca2+ leak, and increased SR Ca2+ load. Ryanodine (10−7 M) inhibition of SR Ca2+ leak suppressed estrogen-induced triggered activities. The rapid response of female myocytes to estrogens was abolished in an estrogen receptor (ER) β knockout mouse model. Conclusions/Significance Physiologically-relevant concentrations of BPA and E2 promote arrhythmias in a female-specific manner in rat hearts; the pro-arrhythmic actions of estrogens are mediated by ERβ-signaling through alterations of myocyte Ca2+ handling, particularly increases in SR Ca2+ leak. Our study provides the first experimental evidence suggesting that exposure to estrogenic endocrine disrupting chemicals and the unique sensitivity of female hearts to estrogens may play a role in arrhythmogenesis in the female heart.
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Affiliation(s)
- Sujuan Yan
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
| | - Yamei Chen
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
| | - Min Dong
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
| | - Weizhong Song
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
| | - Scott M. Belcher
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
| | - Hong-Sheng Wang
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
- * E-mail:
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Abstract
Antiarrhythmic drugs are a group of pharmaceuticals that suppress or prevent abnormal heart rhythms, which are often associated with substantial morbidity and mortality. Current antiarrhythmic drugs that typically target plasma membrane ion channels have limited clinical success and in some cases have been described as being pro-arrhythmic. However, recent studies suggest that pathological release of calcium (Ca(2+)) from the sarcoplasmic reticulum via cardiac ryanodine receptors (RyR2) could represent a promising target for antiarrhythmic therapy. Diastolic SR Ca(2+) release has been linked to arrhythmogenesis in both the inherited arrhythmia syndrome 'catecholaminergic polymorphic ventricular tachycardia' and acquired forms of heart disease (eg, atrial fibrillation, heart failure). Several classes of pharmaceuticals have been shown to reduce abnormal RyR2 activity and may confer protection against triggered arrhythmias through reduction of SR Ca(2+) leak. In this review, we will evaluate the current pharmacological methods for stabilizing RyR2 and suggest treatment modalities based on current evidence of molecular mechanisms.
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17
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Thireau J, Pasquié JL, Martel E, Le Guennec JY, Richard S. New drugs vs. old concepts: a fresh look at antiarrhythmics. Pharmacol Ther 2011; 132:125-45. [PMID: 21420430 DOI: 10.1016/j.pharmthera.2011.03.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2011] [Accepted: 03/01/2011] [Indexed: 01/10/2023]
Abstract
Common arrhythmias, particularly atrial fibrillation (AF) and ventricular tachycardia/fibrillation (VT/VF) are a major public health concern. Classic antiarrhythmic (AA) drugs for AF are of limited effectiveness, and pose the risk of life-threatening VT/VF. For VT/VF, implantable cardiac defibrillators appear to be the unique, yet unsatisfactory, solution. Very few AA drugs have been successful in the last few decades, due to safety concerns or limited benefits in comparison to existing therapy. The Vaughan-Williams classification (one drug for one molecular target) appears too restrictive in light of current knowledge of molecular and cellular mechanisms. New AA drugs such as atrial-specific and/or multichannel blockers, upstream therapy and anti-remodeling drugs, are emerging. We focus on the cellular mechanisms related to abnormal Na⁺ and Ca²⁺ handling in AF, heart failure, and inherited arrhythmias, and on novel strategies aimed at normalizing ionic homeostasis. Drugs that prevent excessive Na⁺ entry (ranolazine) and aberrant diastolic Ca²⁺ release via the ryanodine receptor RyR2 (rycals, dantrolene, and flecainide) exhibit very interesting antiarrhythmic properties. These drugs act by normalizing, rather than blocking, channel activity. Ranolazine preferentially blocks abnormal persistent (vs. normal peak) Na⁺ currents, with minimal effects on normal channel function (cell excitability, and conduction). A similar "normalization" concept also applies to RyR2 stabilizers, which only prevent aberrant opening and diastolic Ca²⁺ leakage in diseased tissues, with no effect on normal function during systole. The different mechanisms of action of AA drugs may increase the therapeutic options available for the safe treatment of arrhythmias in a wide variety of pathophysiological situations.
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Affiliation(s)
- Jérôme Thireau
- Inserm U1046 Physiologie & Médecine Expérimentale du Cœur et des Muscles, Université Montpellier-1, Université Montpellier-2, 34295 Montpellier Cedex 5, France
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18
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van Oort RJ, Garbino A, Wang W, Dixit SS, Landstrom AP, Gaur N, De Almeida AC, Skapura DG, Rudy Y, Burns AR, Ackerman MJ, Wehrens XHT. Disrupted junctional membrane complexes and hyperactive ryanodine receptors after acute junctophilin knockdown in mice. Circulation 2011; 123:979-88. [PMID: 21339484 DOI: 10.1161/circulationaha.110.006437] [Citation(s) in RCA: 204] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Excitation-contraction coupling in striated muscle requires proper communication of plasmalemmal voltage-activated Ca2+ channels and Ca2+ release channels on sarcoplasmic reticulum within junctional membrane complexes. Although previous studies revealed a loss of junctional membrane complexes and embryonic lethality in germ-line junctophilin-2 (JPH2) knockout mice, it has remained unclear whether JPH2 plays an essential role in junctional membrane complex formation and the Ca(2+)-induced Ca(2+) release process in the heart. Our recent work demonstrated loss-of-function mutations in JPH2 in patients with hypertrophic cardiomyopathy. METHODS AND RESULTS To elucidate the role of JPH2 in the heart, we developed a novel approach to conditionally reduce JPH2 protein levels using RNA interference. Cardiac-specific JPH2 knockdown resulted in impaired cardiac contractility, which caused heart failure and increased mortality. JPH2 deficiency resulted in loss of excitation-contraction coupling gain, precipitated by a reduction in the number of junctional membrane complexes and increased variability in the plasmalemma-sarcoplasmic reticulum distance. CONCLUSIONS Loss of JPH2 had profound effects on Ca2+ release channel inactivation, suggesting a novel functional role for JPH2 in regulating intracellular Ca2+ release channels in cardiac myocytes. Thus, our novel approach of cardiac-specific short hairpin RNA-mediated knockdown of junctophilin-2 has uncovered a critical role for junctophilin in intracellular Ca2+ release in the heart.
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Affiliation(s)
- Ralph J van Oort
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, One Baylor Plaza, BCM335, Houston, TX 77030, USA
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19
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Wehrens XHT. CaMKII regulation of the cardiac ryanodine receptor and sarcoplasmic reticulum calcium release. Heart Rhythm 2011; 8:323-5. [PMID: 20887810 PMCID: PMC3020993 DOI: 10.1016/j.hrthm.2010.09.079] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2010] [Accepted: 09/21/2010] [Indexed: 12/19/2022]
Abstract
Spontaneous release of Ca2+ from the sarcoplasmic reticulum has emerged as a mechanism underlying triggered activity and cardiac arrhythmias. Recent studies suggest an important role for increased Ca2+/calmodulin-dependent protein kinase II (CaMKII)-mediated phosphorylation of ryanodine receptors (RyR2) in the induction of arrhythmias. This article briefly reviews the mechanisms underlying CaMKII regulation of RyR2 and discusses directions of current and future research.
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Affiliation(s)
- Xander H T Wehrens
- Department of Molecular Physiology and Biophysics, Department of Medicine (in Cardiology), Baylor College of Medicine, Houston, Texas 77030, USA.
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20
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van Oort RJ, McCauley MD, Dixit SS, Pereira L, Yang Y, Respress JL, Wang Q, De Almeida AC, Skapura DG, Anderson ME, Bers DM, Wehrens XHT. Ryanodine receptor phosphorylation by calcium/calmodulin-dependent protein kinase II promotes life-threatening ventricular arrhythmias in mice with heart failure. Circulation 2010; 122:2669-79. [PMID: 21098440 DOI: 10.1161/circulationaha.110.982298] [Citation(s) in RCA: 235] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
BACKGROUND approximately half of patients with heart failure die suddenly as a result of ventricular arrhythmias. Although abnormal Ca(2+) release from the sarcoplasmic reticulum through ryanodine receptors (RyR2) has been linked to arrhythmogenesis, the molecular mechanisms triggering release of arrhythmogenic Ca(2+) remain unknown. We tested the hypothesis that increased RyR2 phosphorylation by Ca(2+)/calmodulin-dependent protein kinase II is both necessary and sufficient to promote lethal ventricular arrhythmias. METHODS AND RESULTS mice in which the S2814 Ca(2+)/calmodulin-dependent protein kinase II site on RyR2 is constitutively activated (S2814D) develop pathological sarcoplasmic reticulum Ca(2+) release events, resulting in reduced sarcoplasmic reticulum Ca(2+) load on confocal microscopy. These Ca(2+) release events are associated with increased RyR2 open probability in lipid bilayer preparations. At baseline, young S2814D mice have structurally and functionally normal hearts without arrhythmias; however, they develop sustained ventricular tachycardia and sudden cardiac death on catecholaminergic provocation by caffeine/epinephrine or programmed electric stimulation. Young S2814D mice have a significant predisposition to sudden arrhythmogenic death after transverse aortic constriction surgery. Finally, genetic ablation of the Ca(2+)/calmodulin-dependent protein kinase II site on RyR2 (S2814A) protects mutant mice from pacing-induced arrhythmias versus wild-type mice after transverse aortic constriction surgery. CONCLUSIONS our results suggest that Ca(2+)/calmodulin-dependent protein kinase II phosphorylation of RyR2 Ca(2+) release channels at S2814 plays an important role in arrhythmogenesis and sudden cardiac death in mice with heart failure.
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Affiliation(s)
- Ralph J van Oort
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, One Baylor Plaza, BCM335, Houston, TX 77030, USA
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21
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Abstract
Cardiovascular disease is a leading cause of mortality worldwide. While the etiology for the majority of cardiovascular disease is presumed to be a combination of genetic and environmental factors, developments in understanding the basic biology of cardiac disorders have been greatly advanced through discoveries made studying heart diseases that exhibit Mendelian forms of inheritance. Most of these diseases primarily affect children and young adults and include cardiomyopathies, arrhythmias, aortic aneurysms, and congenital heart defects. The discovery of the genetic etiologies for these diseases have had significant impact on our understanding of more complex forms of cardiovascular disease and in some cases have led to novel diagnostic and treatment modalities. In this review, we will summarize these seminal genetic discoveries, highlighting a few that have resulted in significant impact on human disease, and discuss the potential utility of studying Mendelian-inherited heart disease with the development of new genetic technologies and our increased understanding of the human genome.
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Affiliation(s)
- Kim L McBride
- Departments of Pediatrics, The Ohio State University College of Medicine, Columbus, Ohio, USA
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22
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Andersson DC, Marks AR. Fixing ryanodine receptor Ca leak - a novel therapeutic strategy for contractile failure in heart and skeletal muscle. ACTA ACUST UNITED AC 2010; 7:e151-e157. [PMID: 21113427 DOI: 10.1016/j.ddmec.2010.09.009] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
A critical component in regulating cardiac and skeletal muscle contractility is the release of Ca(2+) via ryanodine receptor (RyR) Ca(2+) release channels in the sarcoplasmic reticulum (SR). In heart failure and myopathy, the RyR has been found to be excessively phosphorylated or nitrosylated and depleted of the RyR-stabilizing protein calstabin (FK506 binding protein 12/12.6). This remodeling of the RyR channel complex results in an intracellular SR Ca(2+) leak and impaired contractility. Despite recent advances in heart failure treatment, there are still devastatingly high mortality rates with this disease. Moreover, pharmacological treatment for muscle weakness and myopathy is nearly nonexistent. A novel class of RyR-stabilizing drugs, rycals, which reduce Ca(2+) leak by stabilizing the RyR channels due to preservation of the RyR-calstabin interaction, have recently been shown to improve contractile function in both heart and skeletal muscle. This opens up a novel therapeutic strategy for the treatment of contractile failure in the cardiac and skeletal muscle.
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Affiliation(s)
- Daniel C Andersson
- Department of Physiology and Cellular Biophysics, Clyde and Helen Wu Center for Molecular Cardiology, College of Physicians and Surgeons of Columbia University, New York, NY 10032, USA
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23
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Pessah IN, Cherednichenko G, Lein PJ. Minding the calcium store: Ryanodine receptor activation as a convergent mechanism of PCB toxicity. Pharmacol Ther 2010; 125:260-85. [PMID: 19931307 PMCID: PMC2823855 DOI: 10.1016/j.pharmthera.2009.10.009] [Citation(s) in RCA: 172] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2009] [Accepted: 10/30/2009] [Indexed: 11/24/2022]
Abstract
Chronic low-level polychlorinated biphenyl (PCB) exposures remain a significant public health concern since results from epidemiological studies indicate that PCB burden is associated with immune system dysfunction, cardiovascular disease, and impairment of the developing nervous system. Of these various adverse health effects, developmental neurotoxicity has emerged as a particularly vulnerable endpoint in PCB toxicity. Arguably the most pervasive biological effects of PCBs could be mediated by their ability to alter the spatial and temporal fidelity of Ca2+ signals through one or more receptor-mediated processes. This review will focus on our current knowledge of the structure and function of ryanodine receptors (RyRs) in muscle and nerve cells and how PCBs and related non-coplanar structures alter these functions. The molecular and cellular mechanisms by which non-coplanar PCBs and related structures alter local and global Ca2+ signaling properties and the possible short and long-term consequences of these perturbations on neurodevelopment and neurodegeneration are reviewed.
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Affiliation(s)
- Isaac N Pessah
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, CA 95616, USA.
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24
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Cheng YS, Dai DZ, Dai Y. Stress-induced cardiac insufficiency relating to abnormal leptin and FKBP12.6 is ameliorated by CPU0213, an endothelin receptor antagonist, which is not affected by the CYP3A suppressing effect of erythromycin. J Pharm Pharmacol 2010. [DOI: 10.1211/jpp.61.05.0004] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Abstract
Objectives
Cardiac injury induced by isoprenaline produces stress. This stress can be mediated by the activated endothelin and leptin pathway; thus, the endothelin receptor antagonist CPU0213 may reverse these changes. CPU0213 is metabolized mainly by cytochrome P450 (CYP)3A, thus, erythromycin, an inhibitor of CYP3A, could affect its effects by raising its plasma levels.
Methods
Forty rats were divided into five groups. Group 1 rats were normal. Group 2 rats were administered isoprenaline (1 mg/kg, s.c.) for 10 days. Groups 3, 4 and 5 were administered isoprenaline, but group 3 was given erythromycin (100 mg/kg, p.o.) alone on days six to ten, group 4 was given CPU0213 20 mg/kg (s.c.) on days six to ten, whilst group 5 received erythromycin plus CPU0213 on days six to ten. Measurements were conducted to observe changes in the haemodynamics, cardiac weight index, serum lactate dehydrogenase and creatine kinase levels, and expression of endothelin receptor A (ETa), leptin and its OBRb receptor.
Key findings
In isoprenaline-treated rats, cardiac hypertrophy and dysfunction were found. This was associated with upregulated myocardial leptin protein and OBRb receptor mRNA. Immunohistochemical assay of ETa was upregulated, accompanied with downregulation of FKBP12.6 (calstabin 2) in isoprenaline-treated rats. These effects were significantly reversed by CPU0213. HPLC assay presented an increased plasma level of CPU0213 by erythromycin, but no change in its effects.
Conclusions
CPU0213 improved isoprenaline-induced cardiomyopathy by modulating ETa, leptin and FKBP12.6. However, erythromycin increased plasma levels but did not change its effects.
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Affiliation(s)
- Yu-Si Cheng
- Research Division of Pharmacology, China Pharmaceutical University, Nanjing, China
| | - De-Zai Dai
- Research Division of Pharmacology, China Pharmaceutical University, Nanjing, China
| | - Yin Dai
- Research Division of Pharmacology, China Pharmaceutical University, Nanjing, China
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25
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Thevis M, Thomas A, Kohler M, Beuck S, Möller I, Schäfer M, Rodchenkov G, Yin S, Loo JA, Geyer H, Schänzer W. Mass spectrometry-based characterization of new drugs and methods of performance manipulation in doping control analysis. EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2010; 16:301-312. [PMID: 20530837 DOI: 10.1255/ejms.1047] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Efficient and comprehensive sports drug testing necessitates frequent updating and proactive, preventive anti-doping research, and the early implementation of new, emerging drugs into routine doping controls is an essential aspect. Several new drugs and drug candidates with potential for abuse, including so-called Rycals (ryanodine receptor calstabin complex stabilizers, for example, S-107), hypoxia-inducible factor (HIF) stabilizers, and peroxisome-proliferator-activated receptor (PPAR) delta agonists (for example, GW1516), were studied using different mass spectrometry- and ion mobility-based approaches, and their gas phase dissociation behaviors were elucidated. The detailed knowledge of fragmentation routes allows a more rapid identification of metabolites and structurally related, presumably "tailor-made", analogs potentially designed for doping purposes. The utility of product ion characterization is demonstrated in particular with GW1516, for which oxidation products were readily identified in urine samples by means of diagnostic fragment ions as measured using high resolution/high accuracy mass spectrometry and higher energy collision-induced dissociation (HCD).
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Affiliation(s)
- Mario Thevis
- Center for Preventive Doping Research-Institute of Biochemistry, German Sport University Cologne, Am Sportpark Müngersdorf 6, Cologne, Germany.
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26
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Gwathmey JK, Tsaioun K, Hajjar RJ. Cardionomics: a new integrative approach for screening cardiotoxicity of drug candidates. Expert Opin Drug Metab Toxicol 2009; 5:647-60. [PMID: 19442031 DOI: 10.1517/17425250902932915] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND Despite the FDA guidelines for studies to be performed to rule out potential cardiac toxicity, many drugs have nevertheless entered the market only to be later withdrawn from the market owing to cardiac toxicity. Cardiac toxicity may result from drugs causing impaired function or death of cardiomyocytes, valvular damage, myocardial ischemia and/or ventricular arrhythmias. Negative cardiovascular events have been implicated in 28% of drug withdrawals in the USA. The significance for patients, regulators and the pharmaceutical industry is immense. OBJECTIVE We address whether a more rigorous and integrative approach is needed for cardiovascular safety screening of all new drug candidates. Furthermore, we will present a cardionomics approach that looks at several in vitro and in vivo models that can be applied to all drugs independent of category, therapeutic area or class. METHODS We present examples of drugs demonstrating cardiac toxicity and provide an in-depth review of how calcium homeostasis may be a unifying theme in clinically observed cardiotoxic events. We introduce a cardionomics approach that detects clinical cardiac toxicity early in the drug discovery process, thus, preventing costly late attrition. CONCLUSION The consequences of a failure to detect potential cardiovascular safety issues before clinical launch can have an enormous cost for the pharmaceutical industry, when major drugs are withdrawn due to lawsuits as well as loss of time and resources. An integrated cardionomics approach may reduce the risk of drug withdrawals as a result of unexpected clinical cardiac safety issues.
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Affiliation(s)
- Judith K Gwathmey
- Division of Cardiology, Boston University Medical Center, Cambridge MA 02138, USA.
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27
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Thevis M, Beuck S, Thomas A, Fusshöller G, Sigmund G, Schlörer N, Rodchenkov G, Schäfer M, Schänzer W. Electron ionization mass spectrometry of the ryanodine receptor-based Ca(2+)-channel stabilizer S-107 and its implementation into routine doping control. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2009; 23:2363-2370. [PMID: 19575395 DOI: 10.1002/rcm.4161] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
New insights into the biochemistry of cardiac arrhythmia and skeletal muscle fatigue have yielded new drug candidates to counteract these phenomena. Major biological targets have become ryanodine receptor (RyR)-based Ca(2+)-release channels, which tend to 'leak' under various circumstances including strenuous exercise and, thus, cause aberrant calcium sparks that entail impaired muscle function. Therapeutics, which are referred to as rycals, are currently being developed to treat cardiac arrhythmia via enhancement of calstabin-ryanodine affinities that causes a stabilization of the RyR. These therapeutics possess potential for misuse in sports, and an early implementation of target analytes such as the benzothiazepine derivatives S-107 and JTV-519 or putative metabolites into doping control screening procedures is recommended. Reference compounds, deuterated analogues, and a putative metabolic product were synthesized, and electron ionization mass spectra of these products were studied and dissociation pathways elucidated by means of tandem mass spectrometry (MS/MS) and accurate mass measurements. The characterized analytes were incorporated into existing sports drug testing assays based on liquid-liquid extraction and subsequent gas chromatography/mass spectrometry (GC/MS) analysis, and specificity, lower limit of detection (4-6 ng/mL), intraday and interday precision (1.5-17.2%), as well as recovery (63-66%) were determined. The established procedure proved suitable for routine doping control analysis to detect a potential misuse of the drug candidate S-107 in elite sport.
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Affiliation(s)
- Mario Thevis
- Institute of Biochemistry - Center for Preventive Doping Research, German Sport University Cologne, Am Sportpark Müngersdorf 6, 50933 Cologne, Germany.
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28
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Schulze-Bahr E. Making sense in a nonsense reading frame: suppression of cardiac sodium channel dysfunction. Cardiovasc Res 2009; 83:423-4. [PMID: 19528082 DOI: 10.1093/cvr/cvp196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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29
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Thevis M, Thomas A, Kohler M, Beuck S, Schänzer W. Emerging drugs: mechanism of action, mass spectrometry and doping control analysis. JOURNAL OF MASS SPECTROMETRY : JMS 2009; 44:442-460. [PMID: 19373874 DOI: 10.1002/jms.1584] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The number of compounds and doping methods in sports is in a state of constant flux. In addition to 'traditional' doping agents, such as anabolic androgenic steroids or erythropoietin, new therapeutics and emerging drugs have considerable potential for misuse in elite sport. Such compounds are commonly based on new chemical structures, and the mechanisms underlying their modes of action represent new therapeutic approaches arising from recent advances in medical research; therefore, sports drug testing procedures need to be continuously modified and complementary methods developed, preferably based on mass spectrometry, to enable comprehensive doping controls. This tutorial not only discusses emerging drugs that can be categorized as anabolic agents (selective androgen receptor modulators, SARMs), gene doping [hypoxia-inducible factor stabilizers, peroxisome-proliferator-activated receptor (PPAR)delta-agonists] and erythropoietin-mimetics (Hematide) but also compounds with potentially performance-enhancing properties that are not classified in the current list of the World Anti-Doping Agency. Compounds such as ryanodine-calstabin-complex modulators (benzothiazepines) are included, their mass spectrometric properties discussed, and current approaches in sports drug testing outlined.
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Affiliation(s)
- Mario Thevis
- Center for Preventive Doping Research-Institute of Biochemistry, German Sport University Cologne, Am Sportpark Müngersdorf 6, 50933 Cologne, Germany.
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30
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Liu D, Hewawasam R, Pace SM, Gallant EM, Casarotto MG, Dulhunty AF, Board PG. Dissection of the inhibition of cardiac ryanodine receptors by human glutathione transferase GSTM2-2. Biochem Pharmacol 2009; 77:1181-93. [DOI: 10.1016/j.bcp.2008.12.024] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2008] [Revised: 12/20/2008] [Accepted: 12/22/2008] [Indexed: 11/24/2022]
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31
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Sobie EA. Parameter sensitivity analysis in electrophysiological models using multivariable regression. Biophys J 2009; 96:1264-74. [PMID: 19217846 DOI: 10.1016/j.bpj.2008.10.056] [Citation(s) in RCA: 175] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2008] [Accepted: 10/28/2008] [Indexed: 11/29/2022] Open
Abstract
Computational models of electrical activity and calcium signaling in cardiac myocytes are important tools for understanding physiology. The sensitivity of these models to changes in parameters is often not well-understood, however, because parameter evaluation can be a time-consuming, tedious process. I demonstrate here what I believe is a novel method for rapidly determining how changes in parameters affect outputs. In three models of the ventricular action potential, parameters were randomized, repeated simulations were run, important outputs were calculated, and multivariable regression was performed on the collected results. Random parameters included both maximal rates of ion transport and gating variable characteristics. The procedure generated simplified, empirical models that predicted outputs resulting from new sets of input parameters. The linear regression models were quite accurate, despite nonlinearities in the mechanistic models. Moreover, the regression coefficients, which represent parameter sensitivities, were robust, even when parameters were varied over a wide range. Most importantly, a side-by-side comparison of two similar models identified fundamental differences in model behavior, and revealed model predictions that were both consistent with, and inconsistent with, experimental data. This new method therefore shows promise as a tool for the characterization and assessment of computational models. The general strategy may also suggest methods for integrating traditional quantitative models with large-scale data sets obtained using high-throughput technologies.
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Affiliation(s)
- Eric A Sobie
- Department of Pharmacology and Systems Therapeutics, Mount Sinai School of Medicine, New York, New York 10029, USA.
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32
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Pasquié JL, Richard S. Prolongation in QT interval is not predictive of Ca2+-dependent arrhythmias: implications for drug safety. Expert Opin Drug Saf 2009; 8:57-72. [DOI: 10.1517/14740330802655454] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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33
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Thevis M, Beuck S, Thomas A, Kohler M, Schlörer N, Vajiala I, Schänzer W. Screening for the calstabin-ryanodine receptor complex stabilizers JTV-519 and S-107 in doping control analysis. Drug Test Anal 2009; 1:32-42. [DOI: 10.1002/dta.13] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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34
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Huke S, Bers DM. Ryanodine receptor phosphorylation at Serine 2030, 2808 and 2814 in rat cardiomyocytes. Biochem Biophys Res Commun 2008; 376:80-5. [PMID: 18755143 DOI: 10.1016/j.bbrc.2008.08.084] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2008] [Accepted: 08/20/2008] [Indexed: 10/21/2022]
Abstract
The cardiac ryanodine receptor (RyR) controls Ca2+ release from the sarcoplasmic reticulum (SR) during excitation-contraction coupling. Three phosphorylation sites have been identified: Serine-(S)2808, S2814 and recently S2030. We measured phosphorylation with at least two different antibodies per site and demonstrate that for S2808 results were highly antibody-dependent and two out of three S2808 antibodies did not accurately report phosphorylation level. The RyR was substantially phosphorylated in quiescent rat cardiomyocytes at S2808 and less so at S2814, but appeared to be unphosphorylated at S2030. Basal phosphorylation at S2808/S2814 was maintained by a Ca2+ dependent kinase other than Ca2+/Calmodulin-dependent kinase (CaMKII). During stimulation with Isoproterenol S2808 was phosphorylated by protein kinase A (PKA) and S2814 was phosphorylated by CaMKII. Phosphatase 1 appears to be the main phosphatase dephosphorylating S2808/S2814, but phosphatase 2a may also dephosphorylate S2814. RyR phosphorylation is complex, but important in understanding RyR functional modulation.
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Affiliation(s)
- Sabine Huke
- Department of Physiology, Loyola University Chicago, Maywood, IL 60153, USA; Department of Clinical Pharmacology, Vanderbilt University, Nashville, TN 37232, USA
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35
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Yeh YH, Wakili R, Qi XY, Chartier D, Boknik P, Kääb S, Ravens U, Coutu P, Dobrev D, Nattel S. Calcium-Handling Abnormalities Underlying Atrial Arrhythmogenesis and Contractile Dysfunction in Dogs With Congestive Heart Failure. Circ Arrhythm Electrophysiol 2008; 1:93-102. [DOI: 10.1161/circep.107.754788] [Citation(s) in RCA: 217] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background—
Congestive heart failure (CHF) is a common cause of atrial fibrillation. Focal sources of unknown mechanism have been described in CHF-related atrial fibrillation. The authors hypothesized that abnormal calcium (Ca
2+
) handling contributes to the CHF-related atrial arrhythmogenic substrate.
Methods and Results—
CHF was induced in dogs by ventricular tachypacing (240 bpm �2 weeks). Cellular Ca
2+
-handling properties and expression/phosphorylation status of key Ca
2+
handling and myofilament proteins were assessed in control and CHF atria. CHF decreased cell shortening but increased left atrial diastolic intracellular Ca
2+
concentration ([Ca
2+
]
i
), [Ca
2+
]
i
transient amplitude, and sarcoplasmic reticulum (SR) Ca
2+
load (caffeine-induced [Ca
2+
]
i
release). SR Ca
2+
overload was associated with spontaneous Ca
2+
transient events and triggered ectopic activity, which was suppressed by the inhibition of SR Ca
2+
release (ryanodine) or Na
+
/Ca
2+
exchange. Mechanisms underlying abnormal SR Ca
2+
handling were then studied. CHF increased atrial action potential duration and action potential voltage clamp showed that CHF-like action potentials enhance Ca
2+
i
loading. CHF increased calmodulin-dependent protein kinase II phosphorylation of phospholamban by 120%, potentially enhancing SR Ca
2+
uptake by reducing phospholamban inhibition of SR Ca
2+
ATPase, but it did not affect phosphorylation of SR Ca
2+
-release channels (RyR2). Total RyR2 and calsequestrin (main SR Ca
2+
-binding protein) expression were significantly reduced, by 65% and 15%, potentially contributing to SR dysfunction. CHF decreased expression of total and protein kinase A–phosphorylated myosin-binding protein C (a key contractile filament regulator) by 27% and 74%, potentially accounting for decreased contractility despite increased Ca
2+
transients. Complex phosphorylation changes were explained by enhanced calmodulin-dependent protein kinase IIδ expression and function and type-1 protein-phosphatase activity but downregulated regulatory protein kinase A subunits.
Conclusions—
CHF causes profound changes in Ca
2+
-handling and -regulatory proteins that produce atrial fibrillation–promoting atrial cardiomyocyte Ca
2+
-handling abnormalities, arrhythmogenic triggered activity, and contractile dysfunction.
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Affiliation(s)
- Yung-Hsin Yeh
- From the Department of Medicine and Research Center, Montreal Heart Institute and Université de Montréal (Y.H.Y., R.W., X.Q., D.C., P.C., S.N.), Montreal, Canada; the Department of Pharmacology and Toxicology (R.W., U.R., D.D.), Dresden University of Technology, Dresden, Germany; Chang Gung Memorial Hospital and Chang Gung University (Y.H.Y.), Tao-Yuan, Taiwan; the Department of Pharmacology and Toxicology (P.B.), University of Münster, Münster, Germany; and Ludwig-Maximilians University,
| | - Reza Wakili
- From the Department of Medicine and Research Center, Montreal Heart Institute and Université de Montréal (Y.H.Y., R.W., X.Q., D.C., P.C., S.N.), Montreal, Canada; the Department of Pharmacology and Toxicology (R.W., U.R., D.D.), Dresden University of Technology, Dresden, Germany; Chang Gung Memorial Hospital and Chang Gung University (Y.H.Y.), Tao-Yuan, Taiwan; the Department of Pharmacology and Toxicology (P.B.), University of Münster, Münster, Germany; and Ludwig-Maximilians University,
| | - Xiao-Yan Qi
- From the Department of Medicine and Research Center, Montreal Heart Institute and Université de Montréal (Y.H.Y., R.W., X.Q., D.C., P.C., S.N.), Montreal, Canada; the Department of Pharmacology and Toxicology (R.W., U.R., D.D.), Dresden University of Technology, Dresden, Germany; Chang Gung Memorial Hospital and Chang Gung University (Y.H.Y.), Tao-Yuan, Taiwan; the Department of Pharmacology and Toxicology (P.B.), University of Münster, Münster, Germany; and Ludwig-Maximilians University,
| | - Denis Chartier
- From the Department of Medicine and Research Center, Montreal Heart Institute and Université de Montréal (Y.H.Y., R.W., X.Q., D.C., P.C., S.N.), Montreal, Canada; the Department of Pharmacology and Toxicology (R.W., U.R., D.D.), Dresden University of Technology, Dresden, Germany; Chang Gung Memorial Hospital and Chang Gung University (Y.H.Y.), Tao-Yuan, Taiwan; the Department of Pharmacology and Toxicology (P.B.), University of Münster, Münster, Germany; and Ludwig-Maximilians University,
| | - Peter Boknik
- From the Department of Medicine and Research Center, Montreal Heart Institute and Université de Montréal (Y.H.Y., R.W., X.Q., D.C., P.C., S.N.), Montreal, Canada; the Department of Pharmacology and Toxicology (R.W., U.R., D.D.), Dresden University of Technology, Dresden, Germany; Chang Gung Memorial Hospital and Chang Gung University (Y.H.Y.), Tao-Yuan, Taiwan; the Department of Pharmacology and Toxicology (P.B.), University of Münster, Münster, Germany; and Ludwig-Maximilians University,
| | - Stefan Kääb
- From the Department of Medicine and Research Center, Montreal Heart Institute and Université de Montréal (Y.H.Y., R.W., X.Q., D.C., P.C., S.N.), Montreal, Canada; the Department of Pharmacology and Toxicology (R.W., U.R., D.D.), Dresden University of Technology, Dresden, Germany; Chang Gung Memorial Hospital and Chang Gung University (Y.H.Y.), Tao-Yuan, Taiwan; the Department of Pharmacology and Toxicology (P.B.), University of Münster, Münster, Germany; and Ludwig-Maximilians University,
| | - Ursula Ravens
- From the Department of Medicine and Research Center, Montreal Heart Institute and Université de Montréal (Y.H.Y., R.W., X.Q., D.C., P.C., S.N.), Montreal, Canada; the Department of Pharmacology and Toxicology (R.W., U.R., D.D.), Dresden University of Technology, Dresden, Germany; Chang Gung Memorial Hospital and Chang Gung University (Y.H.Y.), Tao-Yuan, Taiwan; the Department of Pharmacology and Toxicology (P.B.), University of Münster, Münster, Germany; and Ludwig-Maximilians University,
| | - Pierre Coutu
- From the Department of Medicine and Research Center, Montreal Heart Institute and Université de Montréal (Y.H.Y., R.W., X.Q., D.C., P.C., S.N.), Montreal, Canada; the Department of Pharmacology and Toxicology (R.W., U.R., D.D.), Dresden University of Technology, Dresden, Germany; Chang Gung Memorial Hospital and Chang Gung University (Y.H.Y.), Tao-Yuan, Taiwan; the Department of Pharmacology and Toxicology (P.B.), University of Münster, Münster, Germany; and Ludwig-Maximilians University,
| | - Dobromir Dobrev
- From the Department of Medicine and Research Center, Montreal Heart Institute and Université de Montréal (Y.H.Y., R.W., X.Q., D.C., P.C., S.N.), Montreal, Canada; the Department of Pharmacology and Toxicology (R.W., U.R., D.D.), Dresden University of Technology, Dresden, Germany; Chang Gung Memorial Hospital and Chang Gung University (Y.H.Y.), Tao-Yuan, Taiwan; the Department of Pharmacology and Toxicology (P.B.), University of Münster, Münster, Germany; and Ludwig-Maximilians University,
| | - Stanley Nattel
- From the Department of Medicine and Research Center, Montreal Heart Institute and Université de Montréal (Y.H.Y., R.W., X.Q., D.C., P.C., S.N.), Montreal, Canada; the Department of Pharmacology and Toxicology (R.W., U.R., D.D.), Dresden University of Technology, Dresden, Germany; Chang Gung Memorial Hospital and Chang Gung University (Y.H.Y.), Tao-Yuan, Taiwan; the Department of Pharmacology and Toxicology (P.B.), University of Münster, Münster, Germany; and Ludwig-Maximilians University,
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36
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Abstract
Diastolic dysfunction is characterized by prolonged relaxation, increased filling pressure, decreased contraction velocity, and reduced cardiac output. Phenotypical features of diastolic dysfunction can be observed at the level of the isolated myocyte. This article reviews the cellular mechanisms that control relaxation at the level of the myocyte in the healthy situation and discusses the alterations that can affect physiologic function during disease. It focuses specifically on the mechanisms that regulate intracellular calcium handling, and the response of the myofilaments to calcium, including the changes in these components that can contribute to diastolic dysfunction.
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Affiliation(s)
- Muthu Periasamy
- Davis Heart and Lung Research Institute, The Ohio State University, Columbus OH, USA.
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37
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Abstract
Ventricular arrhythmias deteriorating into sudden cardiac death are a major cause of mortality worldwide. The recent linkage of a genetic form of cardiac arrhythmia to mutations in the gene encoding RyR2 (ryanodine receptor 2) has uncovered an important role of this SR (sarcoplasmic reticulum) calcium release channel in triggering arrhythmias. Mutant RyR2 channels give rise to spontaneous release of calcium (Ca(2+)) from the SR during diastole, which enhances the probability of ventricular arrhythmias. Several molecular mechanisms have been proposed to explain the gain-of-function phenotype observed in mutant RyR2 channels. Despite considerable differences between the models discussed in the present review, each predicts spontaneous diastolic Ca(2+) leak from the SR due to incomplete closure of the RyR2 channel. Enhanced SR Ca(2+) leak is also observed in common structural diseases of the heart, such as heart failure. In heart failure, defective channel regulation in the absence of inherited mutations may also increase SR Ca(2+) leak and initiate cardiac arrhythmias. Therefore inhibition of diastolic Ca(2+) leak through SR Ca(2+) release channels has emerged as a new and promising therapeutic target for cardiac arrhythmias.
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38
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Affiliation(s)
- David M. Kaye
- Heart Failure Research Group, Baker Heart Research Institute, Melbourne, Victoria 8008, Australia;
| | - Masahiko Hoshijima
- Institute of Molecular Medicine, University of California, San Diego, La Jolla, California 92093-0346
| | - Kenneth R. Chien
- Cardiovascular Research Center, Massachusetts General Hospital and Harvard Stem Cell Institute, Harvard Medical School, Richard B. Simches Research Centre, Boston, Massachusetts 02114;
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39
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Kaye DM, Krum H. Drug discovery for heart failure: a new era or the end of the pipeline? Nat Rev Drug Discov 2007; 6:127-39. [PMID: 17268484 DOI: 10.1038/nrd2219] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Although there have been significant advances in the therapy of heart failure in recent decades, such as the introduction of beta-blockers and antagonists of the renin-angiotensin system, there is still a major unmet need for better therapies for many patients with heart failure. However, disappointment related to late-stage clinical failures of a number of novel agents, including endothelin antagonists and tumour-necrosis factor blockers, has reduced the impetus of drug development in this field. Here, we review possible targets for heart failure therapy that have emerged from recent progress in our understanding of the underlying disease mechanisms, and highlight key issues that need to be addressed to improve the chances of success of novel therapies directed against these targets.
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Affiliation(s)
- David M Kaye
- Wynn Department of Metabolic Cardiology, Baker Heart Research Institute, PO Box 6492, St Kilda Road Central, Victoria 8008, Australia.
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40
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Abstract
CPU86017 is a novel Class III antiarrhythmic agent derived from berberine and with an improved pharmacological profile, solubility and bioavailability. It is active in suppressing arrhythmias in several animal models. The ED(50) of CPU86017 for suppressing ischemia/reperfusion arrhythmias in rats was 0.22 mg/kg against 2.23 mg/kg for lidocaine. CPU86017 is about 10-fold more potent than lidocaine. It blocks I(K(R.tail)), I(K(S)), and I(Ca(L)) currents with IC(50) values of 25, 14.4, and 11.5 microM, respectively. The plasma t(1/2) of CPU86017, i.v. bolus, in rabbits and dogs is approximately 90 min. The effective plasma levels of CPU86017 in rabbits required to delay the appearance of oubain-induced ventricular arrhythmias is in the range of 0.13-0.31 microg/mL. Higher levels of the drug are required to eliminate ventricular arrhythmias produced by two-stage ligation of the coronary artery in anesthetized dogs. Drug levels in myocardium are much higher than in plasma. CPU80617 has an antioxidant effect that is likely to contribute to its antiarrhythmic activity. The abnormal expression of the ryanodine receptor type 2 (RyR2) and of FKBP12.6 is reduced by CPU80617 during its ventricular tachyarrhythmia-suppressing action. CPU86017 appears to be a promising antiarrhythmic agent with a cardioprotective action. It can be expected to protect from malignant arrhythmias and sudden cardiac death by suppressing molecular events caused by channelopathies.
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Affiliation(s)
- De-Zai Dai
- Research Division of Pharmacology, China Pharmaceutical University, Nanjing, China.
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41
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Durham WJ, Wehrens XHT, Sood S, Hamilton SL. Diseases associated with altered ryanodine receptor activity. Subcell Biochem 2007; 45:273-321. [PMID: 18193641 DOI: 10.1007/978-1-4020-6191-2_10] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Mutations in two intracellular Ca2+ release channels or ryanodine receptors (RyR1 and RyR2) are associated with a number of human skeletal and cardiac diseases. This chapter discusses these diseases in terms of known mechanisms, controversies, and unanswered questions. We also compare the cardiac and skeletal muscle diseases to explore common mechanisms.
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Affiliation(s)
- W J Durham
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX 77030, USA
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42
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Wehrens XHT. The molecular basis of catecholaminergic polymorphic ventricular tachycardia: what are the different hypotheses regarding mechanisms? Heart Rhythm 2006; 4:794-7. [PMID: 17556207 PMCID: PMC3046465 DOI: 10.1016/j.hrthm.2006.12.016] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2006] [Indexed: 10/23/2022]
Affiliation(s)
- Xander H T Wehrens
- Department of Molecular Physiologyand Biophysics, Baylor College of Medicine, Houston, Texas 77030, USA.
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43
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DeWitt MM, MacLeod HM, Soliven B, McNally EM. Phospholamban R14 deletion results in late-onset, mild, hereditary dilated cardiomyopathy. J Am Coll Cardiol 2006; 48:1396-8. [PMID: 17010801 DOI: 10.1016/j.jacc.2006.07.016] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2006] [Revised: 07/10/2006] [Accepted: 07/10/2006] [Indexed: 11/25/2022]
Abstract
OBJECTIVES The purpose of this research was to determine the phenotypic spectrum associated with phospholamban gene (PLN) mutations. BACKGROUND Inheritance contributes to the development of dilated cardiomyopathy. Mutations in the gene encoding PLN have been associated with dilated cardiomyopathy characterized by early onset and the presence of lethal ventricular arrhythmias. METHODS We screened a cohort of 260 unrelated dilated cardiomyopathy patients from a tertiary care referral center for mutations in the PLN gene. RESULTS Family history of cardiomyopathy was present in approximately one-half the individuals in this cohort. We identified 1 family with a deletion of arginine 14 in the PLN. Interestingly, unlike other individuals reported with the identical PLN mutation, these individuals were not diagnosed with dilated cardiomyopathy until their seventh decade when they were only mildly symptomatic with congestive heart failure. CONCLUSIONS The identical PLN mutation can be associated with both mild and severe forms of dilated cardiomyopathy. Additionally, PLN mutations should be considered in late onset cardiomyopathy. (Genetics of Cardiovascular and Neuromuscular Disease; http://www.clinicaltrials.gov/ct/show/NCT00138931?order=1; NCT00138931)
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Affiliation(s)
- Megan M DeWitt
- Department to Medicine, Section of Cardiology, The University of Chicago, Chicago, Illinois, USA
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44
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Lynch MJ, Hill EV, Houslay MD. Intracellular targeting of phosphodiesterase-4 underpins compartmentalized cAMP signaling. Curr Top Dev Biol 2006; 75:225-59. [PMID: 16984814 DOI: 10.1016/s0070-2153(06)75007-4] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The phosphodiesterase-4 (PDE4) enzyme belongs to a family of cAMP-dependent phosphodiesterases that provide the major means of hydrolyzing and, thereby, inactivating the key intracellular second messenger, cAMP. As such, PDE4s are central to the regulation of many diverse signaling processes that allow cells to respond to external stimuli. Four genes (4A, 4B, 4C, and 4D) encode around 20 distinct isoform members of the PDE4 family. Each isoform is characterized by a unique N-terminal region. PDE4s are multidomain metallohydrolases with each domain serving particular roles allowing them to be targeted to varying regions and organelles of intracellular space and regulated in distinct fashions by phosphorylation and protein-protein interaction. Although identical in catalytic function, each isoform locates to distinct regions within the cell so as to create and manage spatially distinct pools of cAMP. The multiplicity of partners associating with members of the four gene PDE4 family places these enzymes in key regulatory positions, permitting them to channel complex biological signals via fundamental signaling cohorts such as G-protein-coupled receptors (GPCRs), arrestins, A-kinase-anchoring proteins (AKAPs), and tyrosyl family kinases. The cAMP cascade has long been linked to cellular growth and embryogenesis and with this comes the implication that PDE4 may play considerable roles in the regulation of progeny development in maturing cells and tissues.
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Affiliation(s)
- Martin J Lynch
- Division of Biochemistry and Molecular Biology, IBLS, Wolfson Building University of Glasgow, Glasgow G12 8QQ, Scotland, United Kingdom
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45
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Schimpf R, Kuschyk J, Veltmann C, Borggrefe M, Wolpert C. [Primary electrical heart disease in adulthood--electrophysiological findings and therapy]. Herzschrittmacherther Elektrophysiol 2005; 16:250-9. [PMID: 16362731 DOI: 10.1007/s00399-005-0492-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2005] [Accepted: 11/10/2005] [Indexed: 05/05/2023]
Abstract
Sudden cardiac death accounts for 100,000 victims in Germany per year. Predominantly, patients with structural heart disease such as coronary artery disease or dilated cardiomyopathy are affected. However, approximately 5-10% of sudden deaths hit patients without structural disease of the heart. The proportion of young patients (< 40 years of age) in this group is even higher (10-20%). In younger patients significantly more diseases like hypertrophic cardiomyopathy, arrhythmogenic right ventricular dysplasia and primary electrical diseases of the heart could be observed such as long QT syndrome, short QT syndrome, Brugada syndrome and catecholaminergic polymorphic ventricular tachycardia. The primary electrical diseases are different concerning their electrocardiographical pattern, clinical triggers of arrhythmias, results of invasive diagnostics and therapy. Meanwhile, molecular genetic screening can reveal specific mutations of ion channels and can identify consecutive functional defects. The significance of programmed ventricular stimulation is at present unclear concerning risk stratification in patients with Brugada syndrome and short QT syndrome and of no significance in long QT syndrome and catecholaminergic polymorphic ventricular tachycardias. The implantable cardioverter defibrillator is the therapy of choice in most symptomatic patients. With increasing knowledge as a result of sophisticated molecular genetic screening, identification of underlying ion channel defects and new details of the mechanisms of arrhythmogenesis, a potential genotype-guided therapy will gain more importance in the future.
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Affiliation(s)
- R Schimpf
- I. Medizinische Klinik, Universitätsklinikum Mannheim, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim.
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