1
|
Lazzerini PE, Bertolozzi I, Cartocci A, Ginjupalli VKM, Teneggi PA, Pica D, Merico G, Bogazzi I, Salvini V, Accioli R, Salvadori F, Marzotti T, Cevenini G, Capecchi M, Cantara S, Cantore A, Infantino M, Bisogno S, Finizola F, D'ascenzi F, Laghi‐Pasini F, Acampa M, Capecchi PL, Boutjdir M. Advanced Atrioventricular Block in Athletes: Prevalence and Role of Anti-Ro/Sjögren Syndrome-Related Antigen A Antibodies. J Am Heart Assoc 2024; 13:e034893. [PMID: 38879447 PMCID: PMC11255775 DOI: 10.1161/jaha.124.034893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Accepted: 04/15/2024] [Indexed: 06/19/2024]
Abstract
BACKGROUND Advanced atrioventricular block (AVB), that is, higher than second-degree Mobitz-1, is an abnormal finding in athletes. Despite intensive investigation, in several cases the pathogenesis remains unknown, but frequently pacemaker implantation is still indicated. Increasing evidence points to circulating anti-Ro/Sjögren syndrome-related antigen A (SSA) antibodies cross-reacting with L-type calcium channel and inhibiting the related current as an epidemiologically relevant and potentially reversible cause of isolated AVB in adults. The aim of the study was to determine the prevalence of anti-Ro/SSA-associated advanced AVBs in a large sample of young athletes. METHODS AND RESULTS A total of 2536 consecutive athletes aged <40 years without a history of cardiac diseases/interventions were enrolled in a cross-sectional study. Resting and exercise electrocardiography was performed, and those presenting any AVB were further evaluated by 24-hour Holter ECG. Athletes with second-degree AVBs and their mothers underwent anti-Ro/SSA testing. Moreover, purified immunoglobulin G from subjects with anti-Ro/SSA-positive and anti-Ro/SSA-negative advanced AVB were tested on L-type calcium current and L-type-calcium channel expression using tSA201 cells. The global prevalence of advanced AVB in the overall sample was ≈0.1%, but the risk considerably increased (2%) when intensely trained postpubertal male subjects were selectively considered. While none of the athletes with advanced AVB showed heart abnormalities, in 100% of cases anti-Ro/SSA antibodies were detected. Ex vivo experiments showed that immunoglobulin G from anti-Ro/SSA-positive but not -negative subjects with advanced AVB acutely inhibit L-type calcium current and chronically downregulate L-type-calcium channel expression. CONCLUSIONS Our study provides evidence that advanced AVB occurs in young athletes, in most cases associated with anti-Ro/SSA antibodies blocking L-type calcium channels. These findings may open new avenues for immunomodulating therapies to reduce the risk of life-threatening events in athletes, avoiding or delaying pacemaker implantation.
Collapse
Affiliation(s)
- Pietro Enea Lazzerini
- Department of Medical SciencesSurgery and Neurosciences, Division of Internal Medicine and Geriatrics, Electroimmunology UnitUniversity of SienaSienaItaly
| | - Iacopo Bertolozzi
- Cardiology Intensive Therapy UnitDepartment of Internal MedicineNuovo Ospedale San Giovanni di DioFlorenceItaly
- Former Cardiology Intensive Therapy Unit, Department of Internal MedicineHospital of CarraraCarraraItaly
| | | | | | | | - Davide Pica
- Center for Sports Medicine of CarraraASL Nord‐Ovest ToscanaMassa‐CarraraItaly
| | - Giovanni Merico
- Center for Sports Medicine of CarraraASL Nord‐Ovest ToscanaMassa‐CarraraItaly
| | - Irene Bogazzi
- Emergency DepartmentNuovo Ospedale ApuanoASL Nord‐Ovest ToscanaMassa‐CarraraItaly
| | - Viola Salvini
- Department of Medical SciencesSurgery and Neurosciences, Division of Internal Medicine and Geriatrics, Electroimmunology UnitUniversity of SienaSienaItaly
| | - Riccardo Accioli
- Department of Medical SciencesSurgery and Neurosciences, Division of Internal Medicine and Geriatrics, Electroimmunology UnitUniversity of SienaSienaItaly
| | - Fabio Salvadori
- Department of Medical SciencesSurgery and Neurosciences, Division of Internal Medicine and Geriatrics, Electroimmunology UnitUniversity of SienaSienaItaly
| | - Tommaso Marzotti
- Department of Medical SciencesSurgery and Neurosciences, Division of Internal Medicine and Geriatrics, Electroimmunology UnitUniversity of SienaSienaItaly
| | | | - Matteo Capecchi
- Department of Medical SciencesSurgery and Neurosciences, Division of Internal Medicine and Geriatrics, Electroimmunology UnitUniversity of SienaSienaItaly
| | - Silvia Cantara
- Department of Medical SciencesSurgery and Neurosciences, Division of Internal Medicine and Geriatrics, Electroimmunology UnitUniversity of SienaSienaItaly
- Laboratory of Clinical and Translational ResearchUniversity Hospital of SienaSienaItaly
| | - Anna Cantore
- Department of Medical SciencesSurgery and Neurosciences, Division of Internal Medicine and Geriatrics, Electroimmunology UnitUniversity of SienaSienaItaly
| | - Maria Infantino
- Immunology and Allergology Laboratory Unit S. Giovanni di Dio HospitalFlorenceItaly
| | - Stefania Bisogno
- Department of Medical SciencesSurgery and Neurosciences, Division of Internal Medicine and Geriatrics, Electroimmunology UnitUniversity of SienaSienaItaly
| | - Francesco Finizola
- Internal Medicine DepartmentSant’Antonio Abate Hospital of FivizzanoASL Nord‐Ovest ToscanaMassa‐CarraraItaly
| | - Flavio D'ascenzi
- Department of Medical BiotechnologiesSports Cardiology and Rehabilitation UnitUniversity of SienaSienaItaly
| | - Franco Laghi‐Pasini
- Department of Medical SciencesSurgery and Neurosciences, Division of Internal Medicine and Geriatrics, Electroimmunology UnitUniversity of SienaSienaItaly
| | | | - Pier Leopoldo Capecchi
- Department of Medical SciencesSurgery and Neurosciences, Division of Internal Medicine and Geriatrics, Electroimmunology UnitUniversity of SienaSienaItaly
| | - Mohamed Boutjdir
- Department of Medical BiotechnologiesUniversity of SienaSienaItaly
- New York University Grossman School of MedicineNew YorkNYUSA
| |
Collapse
|
2
|
Zaveri S, Srivastava U, Qu YS, Chahine M, Boutjdir M. Pathophysiology of Ca v1.3 L-type calcium channels in the heart. Front Physiol 2023; 14:1144069. [PMID: 37025382 PMCID: PMC10070707 DOI: 10.3389/fphys.2023.1144069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Accepted: 03/07/2023] [Indexed: 04/08/2023] Open
Abstract
Ca2+ plays a crucial role in excitation-contraction coupling in cardiac myocytes. Dysfunctional Ca2+ regulation alters the force of contraction and causes cardiac arrhythmias. Ca2+ entry into cardiomyocytes is mediated mainly through L-type Ca2+ channels, leading to the subsequent Ca2+ release from the sarcoplasmic reticulum. L-type Ca2+ channels are composed of the conventional Cav1.2, ubiquitously expressed in all heart chambers, and the developmentally regulated Cav1.3, exclusively expressed in the atria, sinoatrial node, and atrioventricular node in the adult heart. As such, Cav1.3 is implicated in the pathogenesis of sinoatrial and atrioventricular node dysfunction as well as atrial fibrillation. More recently, Cav1.3 de novo expression was suggested in heart failure. Here, we review the functional role, expression levels, and regulation of Cav1.3 in the heart, including in the context of cardiac diseases. We believe that the elucidation of the functional and molecular pathways regulating Cav1.3 in the heart will assist in developing novel targeted therapeutic interventions for the aforementioned arrhythmias.
Collapse
Affiliation(s)
- Sahil Zaveri
- Cardiovascular Research Program, VA New York Harbor Healthcare System, New York, NY, United States
- Department of Medicine, Cell Biology and Pharmacology, State University of New York Downstate Health Sciences University, Brooklyn, New York, NY, United States
| | - Ujala Srivastava
- Cardiovascular Research Program, VA New York Harbor Healthcare System, New York, NY, United States
| | - Yongxia Sarah Qu
- Cardiovascular Research Program, VA New York Harbor Healthcare System, New York, NY, United States
- Department of Medicine, Cell Biology and Pharmacology, State University of New York Downstate Health Sciences University, Brooklyn, New York, NY, United States
- Department of Cardiology, New York Presbyterian Brooklyn Methodist Hospital, New York, NY, United States
| | - Mohamed Chahine
- CERVO Brain Research Center, Institut Universitaire en Santé Mentale de Québec, Québec, QC, Canada
- Department of Medicine, Faculté de Médecine, Université Laval, Quebec, QC, Canada
| | - Mohamed Boutjdir
- Cardiovascular Research Program, VA New York Harbor Healthcare System, New York, NY, United States
- Department of Medicine, Cell Biology and Pharmacology, State University of New York Downstate Health Sciences University, Brooklyn, New York, NY, United States
- Division of Cardiology, Department of Medicine, NYU Grossman School of Medicine, New York, NY, United States
- *Correspondence: Mohamed Boutjdir,
| |
Collapse
|
3
|
Hodges SL, Bouza AA, Isom LL. Therapeutic Potential of Targeting Regulated Intramembrane Proteolysis Mechanisms of Voltage-Gated Ion Channel Subunits and Cell Adhesion Molecules. Pharmacol Rev 2022; 74:1028-1048. [PMID: 36113879 PMCID: PMC9553118 DOI: 10.1124/pharmrev.121.000340] [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: 11/08/2021] [Accepted: 05/13/2022] [Indexed: 10/03/2023] Open
Abstract
Several integral membrane proteins undergo regulated intramembrane proteolysis (RIP), a tightly controlled process through which cells transmit information across and between intracellular compartments. RIP generates biologically active peptides by a series of proteolytic cleavage events carried out by two primary groups of enzymes: sheddases and intramembrane-cleaving proteases (iCLiPs). Following RIP, fragments of both pore-forming and non-pore-forming ion channel subunits, as well as immunoglobulin super family (IgSF) members, have been shown to translocate to the nucleus to function in transcriptional regulation. As an example, the voltage-gated sodium channel β1 subunit, which is also an IgSF-cell adhesion molecule (CAM), is a substrate for RIP. β1 RIP results in generation of a soluble intracellular domain, which can regulate gene expression in the nucleus. In this review, we discuss the proposed RIP mechanisms of voltage-gated sodium, potassium, and calcium channel subunits as well as the roles of their generated proteolytic products in the nucleus. We also discuss other RIP substrates that are cleaved by similar sheddases and iCLiPs, such as IgSF macromolecules, including CAMs, whose proteolytically generated fragments function in the nucleus. Importantly, dysfunctional RIP mechanisms are linked to human disease. Thus, we will also review how understanding RIP events and subsequent signaling processes involving ion channel subunits and IgSF proteins may lead to the discovery of novel therapeutic targets. SIGNIFICANCE STATEMENT: Several ion channel subunits and immunoglobulin superfamily molecules have been identified as substrates of regulated intramembrane proteolysis (RIP). This signal transduction mechanism, which generates polypeptide fragments that translocate to the nucleus, is an important regulator of gene transcription. RIP may impact diseases of excitability, including epilepsy, cardiac arrhythmia, and sudden death syndromes. A thorough understanding of the role of RIP in gene regulation is critical as it may reveal novel therapeutic strategies for the treatment of previously intractable diseases.
Collapse
Affiliation(s)
- Samantha L Hodges
- Departments of Pharmacology (S.L.H., A.A.B., L.L.I.), Neurology (L.L.I.), and Molecular & Integrative Physiology (L.L.I.), University of Michigan Medical School, Ann Arbor, Michigan
| | - Alexandra A Bouza
- Departments of Pharmacology (S.L.H., A.A.B., L.L.I.), Neurology (L.L.I.), and Molecular & Integrative Physiology (L.L.I.), University of Michigan Medical School, Ann Arbor, Michigan
| | - Lori L Isom
- Departments of Pharmacology (S.L.H., A.A.B., L.L.I.), Neurology (L.L.I.), and Molecular & Integrative Physiology (L.L.I.), University of Michigan Medical School, Ann Arbor, Michigan
| |
Collapse
|
4
|
Novel re-expression of L-type calcium channel Ca v1.3 in left ventricles of failing human heart. Heart Rhythm 2020; 17:1193-1197. [PMID: 32113898 DOI: 10.1016/j.hrthm.2020.02.025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Accepted: 02/19/2020] [Indexed: 11/17/2022]
|
5
|
Qu YS, Lazzerini PE, Capecchi PL, Laghi-Pasini F, El Sherif N, Boutjdir M. Autoimmune Calcium Channelopathies and Cardiac Electrical Abnormalities. Front Cardiovasc Med 2019; 6:54. [PMID: 31119135 PMCID: PMC6507622 DOI: 10.3389/fcvm.2019.00054] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Accepted: 04/16/2019] [Indexed: 12/24/2022] Open
Abstract
Patients with autoimmune diseases are at increased risk for developing cardiovascular diseases, and abnormal electrocardiographic findings are common. Voltage-gated calcium channels play a major role in the cardiovascular system and regulate cardiac excitability and contractility. Particularly, by virtue of their localization and expression in the heart, calcium channels modulate pace making at the sinus node, conduction at the atrioventricular node and cardiac repolarization in the working myocardium. Consequently, emerging evidence suggests that calcium channels are targets to autoantibodies in autoimmune diseases. Autoimmune-associated cardiac calcium channelopathies have been recognized in both sinus node dysfunction atrioventricular block in patients positive for anti-Ro/La antibodies, and ventricular arrhythmias in patients with dilated cardiomyopathy. In this review, we discuss mechanisms of autoimmune-associated calcium channelopathies and their relationship with the development of cardiac electrical abnormalities.
Collapse
Affiliation(s)
- Yongxia Sarah Qu
- Department of Cardiology, New York Presbyterian Brooklyn Methodist Hospital, Brooklyn, NY, United States.,VA New York Harbor Healthcare System and State University of New York Downstate Medical Center, Brooklyn, NY, United States
| | - Pietro Enea Lazzerini
- Department of Medical Sciences, Surgery and Neurosciences, University of Siena, Siena, Italy
| | - Pier Leopoldo Capecchi
- Department of Medical Sciences, Surgery and Neurosciences, University of Siena, Siena, Italy
| | - Franco Laghi-Pasini
- Department of Medical Sciences, Surgery and Neurosciences, University of Siena, Siena, Italy
| | - Nabil El Sherif
- VA New York Harbor Healthcare System and State University of New York Downstate Medical Center, Brooklyn, NY, United States
| | - Mohamed Boutjdir
- VA New York Harbor Healthcare System and State University of New York Downstate Medical Center, Brooklyn, NY, United States.,NYU School of Medicine, New York, NY, United States
| |
Collapse
|
6
|
Sagawa H, Hoshino S, Yoshioka K, Ding WG, Omatsu-Kanbe M, Nakagawa M, Maruo Y, Matsuura H. Postnatal developmental changes in the sensitivity of L-type Ca 2+ channel to inhibition by verapamil in a mouse heart model. Pediatr Res 2018; 83:1207-1217. [PMID: 29554082 DOI: 10.1038/pr.2018.46] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Accepted: 01/29/2018] [Indexed: 11/09/2022]
Abstract
BackgroundIn the clinical setting, verapamil is contraindicated in neonates and infants, because of the perceived risk of hypotension or bradyarrhythmia. However, it remains unclear whether there is an age-dependent difference in the sensitivity of cardiac L-type Ca2+ channel current (ICa,L) to inhibition by verapamil.MethodsVentricular myocytes were enzymatically dissociated from the hearts of six different age groups (0, 7, 14, 21, 28 days, and 10-15 weeks) of mice, using a similar Langendorff-perfusion method. Whole-cell patch-clamp technique was applied to examine the sensitivity of ICa,L to inhibition, by three classes of structurally different L-type Ca2+ channel antagonists.ResultsVerapamil, nifedipine, and diltiazem concentration-dependently blocked the ventricular ICa,L in all six age groups. However, although nifedipine and diltiazem blocked ventricular ICa,L with a similar potency in all age groups, verapamil more potently blocked ventricular ICa,L in day 0, day 7, day 14, and day 21 mice, than in day 28, and 10-15-week mice.ConclusionIn a mouse heart model, ventricular ICa,L before the weaning age (~21 days of age) exhibited a higher sensitivity to inhibition by verapamil than that after the weaning age, which may explain one possible mechanism associated with the development of verapamil-induced hypotension in human neonates and infants.
Collapse
Affiliation(s)
- Hironori Sagawa
- Department of Physiology, Shiga University of Medical Science, Otsu, Shiga, Japan
| | - Shinsuke Hoshino
- Department of Pediatrics, Shiga University of Medical Science, Otsu, Shiga, Japan
| | - Kengo Yoshioka
- Department of Physiology, Shiga University of Medical Science, Otsu, Shiga, Japan
| | - Wei-Guang Ding
- Department of Physiology, Shiga University of Medical Science, Otsu, Shiga, Japan
| | - Mariko Omatsu-Kanbe
- Department of Physiology, Shiga University of Medical Science, Otsu, Shiga, Japan
| | - Masao Nakagawa
- Department of Pediatrics, Shiga University of Medical Science, Otsu, Shiga, Japan
| | - Yoshihiro Maruo
- Department of Pediatrics, Shiga University of Medical Science, Otsu, Shiga, Japan
| | - Hiroshi Matsuura
- Department of Physiology, Shiga University of Medical Science, Otsu, Shiga, Japan
| |
Collapse
|
7
|
Fernández-Morales JC, Morad M. Regulation of Ca 2+ signaling by acute hypoxia and acidosis in rat neonatal cardiomyocytes. J Mol Cell Cardiol 2017; 114:58-71. [PMID: 29032102 DOI: 10.1016/j.yjmcc.2017.10.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Revised: 09/20/2017] [Accepted: 10/08/2017] [Indexed: 11/25/2022]
Abstract
Ischemic heart disease is an arrhythmogenic condition, accompanied by hypoxia, acidosis, and impaired Ca2+ signaling. Here we report on effects of acute hypoxia and acidification in rat neonatal cardiomyocytes cultures. RESULTS Two populations of neonatal cardiomyocyte were identified based on inactivation kinetics of L-type ICa: rapidly-inactivating ICa (τ~20ms) myocytes (prevalent in 3-4-day cultures), and slow-inactivating ICa (τ≥40ms) myocytes (dominant in 7-day cultures). Acute hypoxia (pO2<5mmHg for 50-100s) suppressed ICa reversibly in both cell-types to different extent and with different kinetics. This disparity disappeared when Ba2+ was the channel charge carrier, or when the intracellular Ca2+ buffering capacity was increased by dialysis of high concentrations of EGTA and BAPTA, suggesting critical role for calcium-dependent inactivation. Suppressive effect of acute acidosis on ICa (~40%, pH6.7), on the other hand, was not cell-type dependent. Isoproterenol enhanced ICa in both cell-types, but protected only against suppressive effects of acidosis and not hypoxia. Hypoxia and acidosis suppressed global Ca2+ transients by ~20%, but suppression was larger, ~35%, at the RyR2 microdomains, using GCaMP6-FKBP targeted probe. Hypoxia and acidosis also suppressed mitochondrial Ca2+ uptake by 40% and 10%, respectively, using mitochondrial targeted Ca2+ biosensor (mito-GCaMP6). CONCLUSION Our studies suggest that acute hypoxia suppresses ICa in rapidly inactivating cell population by a mechanism involving Ca2+-dependent inactivation, while compromised mitochondrial Ca2+ uptake seems also to contribute to ICa suppression in slowly inactivating cell population. Proximity of cellular Ca2+ pools to sarcolemmal Ca2+ channels may contribute to the variability of inactivation kinetics of ICa in the two cell populations, while acidosis suppression of ICa appears mediated by proton-induced block of the calcium channel.
Collapse
Affiliation(s)
| | - Martin Morad
- Cardiac Signaling Center of MUSC, USC and Clemson, Charleston, SC, USA; Department of Pharmacology, Georgetown University Medical Center, Washington, DC, USA.
| |
Collapse
|
8
|
Novel function of α 1D L-type calcium channel in the atria. Biochem Biophys Res Commun 2017; 482:771-776. [DOI: 10.1016/j.bbrc.2016.11.109] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Accepted: 11/18/2016] [Indexed: 11/24/2022]
|
9
|
Li W, Zheng NZ, Yuan Q, Xu K, Yang F, Gu L, Zheng GY, Luo GJ, Fan C, Ji GJ, Zhang B, Cao H, Tian XL. NFAT5-mediated CACNA1C expression is critical for cardiac electrophysiological development and maturation. J Mol Med (Berl) 2016; 94:993-1002. [PMID: 27368804 DOI: 10.1007/s00109-016-1444-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Revised: 06/18/2016] [Accepted: 06/24/2016] [Indexed: 01/30/2023]
Abstract
UNLABELLED Entry of calcium into cardiomyocyte via L-type calcium channel (LTCC) is fundamental to cardiac contraction. CACNA1C, a type of LTCC and a hallmark of a matured ventricular myocyte, is developmentally regulated. Here, we identified 138 potential transcription factors by a comparative genomic study on 5-kb promoter regions of CACNA1C gene across eight vertebrate species, and showed that six factors were developmentally regulated with the expression of Cacna1c in mouse P19cl6 in vitro cardiomyocyte differentiation model. We further demonstrated that the nuclear factor of activated T cells 5 (Nfat5) bound to a consensus sequence TGGAAGCGTTC and activated the transcription of Cacna1c. The siRNA-mediated knockdown of Nfat5 suppressed the expression of Cacna1c and decreased L-type calcium current in mouse neonatal cardiomyocytes. Furthermore, morpholino-mediated knockdown of nfat5 in zebrafish prohibited the expression of cacna1c and resulted in a non-contractile ventricle, while over-expression of either cacna1c or nfat5 rescued this impaired phenotype. Thus, NFAT5-mediated expression of CACNA1C is evolutionarily conserved and critical for cardiac electrophysiological development and maturation of cardiomyocyte. KEY MESSAGE Nfat5 binds to a consensus sequence TGGAAGCGTTC in the promoter of Cacna1c. Nfat5 activates the transcription of Cacna1c. Nfat5 knockdown suppresses Cacna1c expression, decreases L-type calcium current, and results in non-beating ventricle. NFAT5-mediated expression of CACNA1C is evolutionarily conserved. NFAT5-mediated CACNA1C expression is critical for cardiac electrophysiological development and maturation.
Collapse
Affiliation(s)
- Wei Li
- Department of Human Population Genetics, Institute of Molecular Medicine, Peking University, 5 Yiheyuan Road, Beijing, 100871, China
| | - Nai-Zhong Zheng
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, College of Life Sciences, Peking University, 5 Yiheyuan Road, Beijing, 100871, China
| | - Qi Yuan
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Chaoyang District, Beijing, 100101, China
| | - Ke Xu
- Department of Human Population Genetics, Institute of Molecular Medicine, Peking University, 5 Yiheyuan Road, Beijing, 100871, China
| | - Fan Yang
- Department of Human Population Genetics, Institute of Molecular Medicine, Peking University, 5 Yiheyuan Road, Beijing, 100871, China
| | - Lei Gu
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Chaoyang District, Beijing, 100101, China
| | - Gu-Yan Zheng
- Department of Human Population Genetics, Institute of Molecular Medicine, Peking University, 5 Yiheyuan Road, Beijing, 100871, China
| | - Guo-Jie Luo
- School of Electronics Engineering and Computer Science, Peking University, 5 Yiheyuan Road, Beijing, 100871, China
| | - Chun Fan
- Department of Biomedical Engineering, Lerner Research Institute, The Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH, 44195, USA
| | - Guang-Ju Ji
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Chaoyang District, Beijing, 100101, China
| | - Bo Zhang
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, College of Life Sciences, Peking University, 5 Yiheyuan Road, Beijing, 100871, China
| | - Huiqing Cao
- Department of Human Population Genetics, Institute of Molecular Medicine, Peking University, 5 Yiheyuan Road, Beijing, 100871, China.
| | - Xiao-Li Tian
- Department of Human Population Genetics, Institute of Molecular Medicine, Peking University, 5 Yiheyuan Road, Beijing, 100871, China.
| |
Collapse
|
10
|
Freeman JL, Weber GJ, Peterson SM, Nie LH. Embryonic ionizing radiation exposure results in expression alterations of genes associated with cardiovascular and neurological development, function, and disease and modified cardiovascular function in zebrafish. Front Genet 2014; 5:268. [PMID: 25147559 PMCID: PMC4124797 DOI: 10.3389/fgene.2014.00268] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Accepted: 07/21/2014] [Indexed: 01/16/2023] Open
Abstract
The relationship between ionizing radiation (IR) and carcinogenesis is long established, but recently the association between IR and other diseases is starting to be recognized. Currently, there is limited information on the genetic mechanisms governing the role of IR in non-cancer related adverse health effects and in regards to an early developmental exposure. In this study, zebrafish embryos were exposed to a range of IR doses (0, 1, 2, 5, 10 Gy) at 26 h post fertilization (hpf). No significant increase in mortality or hatching rate was observed, but a significant decrease in total larval length, head length, and eye diameter was observed in the 10 Gy dose. Transcriptomic analysis was conducted at 120 hpf to compare gene expression profiles between the control and highest IR dose at which no significant differences were observed in morphological measurements (5 Gy). 253 genes with well-established function or orthology to human genes were significantly altered. Gene ontology and molecular network analysis revealed enrichment of genes associated with cardiovascular and neurological development, function, and disease. Expression of a subset of genetic targets with an emphasis on those associated with the cardiovascular system was assessed using Quantitative PCR (qPCR) to confirm altered expression at 5 Gy and then to investigate alterations at lower doses (1 and 2 Gy). Strong correlation between microarray and qPCR expression values was observed, but zebrafish exposed to 1 or 2 Gy resulted in a significant expression alteration in only one of these genes (LIN7B). Moreover, heart rate was analyzed through 120 hpf following IR dosing at 26 hpf. A significant decrease in heart rate was observed at 10 Gy, while a significant increase in heart rate was observed at 1, 2, and 5 Gy. Overall these findings indicate IR exposure at doses below those that induce gross morphological changes alters heart rate and expression of genes associated with cardiovascular and neurological functions.
Collapse
Affiliation(s)
| | - Gregory J Weber
- School of Health Sciences, Purdue University West Lafayette, IN, USA
| | - Samuel M Peterson
- School of Health Sciences, Purdue University West Lafayette, IN, USA
| | - Linda H Nie
- School of Health Sciences, Purdue University West Lafayette, IN, USA
| |
Collapse
|
11
|
Hofmann F, Flockerzi V, Kahl S, Wegener JW. L-type CaV1.2 calcium channels: from in vitro findings to in vivo function. Physiol Rev 2014; 94:303-26. [PMID: 24382889 DOI: 10.1152/physrev.00016.2013] [Citation(s) in RCA: 235] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
The L-type Cav1.2 calcium channel is present throughout the animal kingdom and is essential for some aspects of CNS function, cardiac and smooth muscle contractility, neuroendocrine regulation, and multiple other processes. The L-type CaV1.2 channel is built by up to four subunits; all subunits exist in various splice variants that potentially affect the biophysical and biological functions of the channel. Many of the CaV1.2 channel properties have been analyzed in heterologous expression systems including regulation of the L-type CaV1.2 channel by Ca(2+) itself and protein kinases. However, targeted mutations of the calcium channel genes confirmed only some of these in vitro findings. Substitution of the respective serines by alanine showed that β-adrenergic upregulation of the cardiac CaV1.2 channel did not depend on the phosphorylation of the in vitro specified amino acids. Moreover, well-established in vitro phosphorylation sites of the CaVβ2 subunit of the cardiac L-type CaV1.2 channel were found to be irrelevant for the in vivo regulation of the channel. However, the molecular basis of some kinetic properties, such as Ca(2+)-dependent inactivation and facilitation, has been approved by in vivo mutagenesis of the CaV1.2α1 gene. This article summarizes recent findings on the in vivo relevance of well-established in vitro results.
Collapse
|
12
|
Cardiac functions of voltage-gated Ca(2+) channels: role of the pharmacoresistant type (E-/R-Type) in cardiac modulation and putative implication in sudden unexpected death in epilepsy (SUDEP). Rev Physiol Biochem Pharmacol 2014; 167:115-39. [PMID: 25280639 DOI: 10.1007/112_2014_21] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Voltage-gated Ca(2+) channels (VGCCs) are ubiquitous in excitable cells. These channels play key roles in many physiological events like cardiac regulation/pacemaker activity due to intracellular Ca(2+) transients. In the myocardium, the Cav1 subfamily (L-type: Cav1.2 and Cav1.3) is the main contributor to excitation-contraction coupling and/or pacemaking, whereas the Cav3 subfamily (T-type: Cav3.1 and Cav3.2) is important in rhythmically firing of the cardiac nodal cells. No established cardiac function has been attributed to the Cav2 family (E-/R-type: Cav2.3) despite accumulating evidence of cardiac dysregulation observed upon deletion of the Cav2.3 gene, the only member of this family so far detected in cardiomyocytes. In this review, we summarize the pathophysiological changes observed after ablation of the E-/R-type VGCC and propose a cardiac mechanism of action for this channel. Also, considering the role played by this channel in epilepsy and its reported sensitivity to antiepileptic drugs, a putative involvement of this channel in the cardiac mechanism of sudden unexpected death in epilepsy is also discussed.
Collapse
|
13
|
Pochaev VA, Krasnyi AM, Ozernyuk ND. Influx of Ca2+ via Cav1.3 calcium channels in satellite cells of muscle fibers in rats. BIOL BULL+ 2013. [DOI: 10.1134/s1062359013050129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
14
|
Karnabi E, Qu Y, Yue Y, Boutjdir M. Calreticulin negatively regulates the surface expression of Cav1.3 L-type calcium channel. Biochem Biophys Res Commun 2013; 437:497-501. [PMID: 23791743 DOI: 10.1016/j.bbrc.2013.06.023] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Accepted: 06/08/2013] [Indexed: 12/19/2022]
Abstract
BACKGROUND The neuroendocrine Cav1.3 L-type Ca channels have been recently found in the Human fetal heart and shown to play a vital role in Ca entry from the sarcolemma into the cell and in Ca homeostasis. Calreticulin, a Ca binding endoplasmic reticulum (ER) resident protein, has been recently shown to translocate to the cell surface where its role and function are just emerging. Here, we demonstrated a novel mechanism of Cav1.3 and calreticulin interaction resulting in downregulation of Cav1.3 channel densities in native Human fetal cardiac cells and Human Embryonic Kidney cell lines (tsA201). METHODS AND RESULTS Cell surface and cytoplasmic staining of calreticulin was demonstrated first in cultured human fetal cardiomyocytes (HFC), gestational age 18-24 weeks, using confocal microscopy thereby establishing that calreticulin is present at the cell surface in HFC. Co-immunoprecipitation from HFC using anti-Cav1.3 Ca channel antibody, and probing with anti-calreticulin antibody revealed a 46 kDa band corresponding to calreticulin suggesting that Cav1.3 Ca channel and calreticulin co-assemble in a macromolecular complex. Co-expression of Cav1.3 and calreticulin in tsA201 cells resulted in a decrease in surface expression of Cav1.3 Ca channels. These findings were consistent with the electrophysiological studies showing that co-transfection of Cav1.3 Ca channel and calreticulin resulted in 55% reduction of Cav1.3 Ca current densities recorded from tsA201 cells. CONCLUSIONS The results show the first evidence that calreticulin: (1) is localized outside the ER on the cell surface of HFC; (2) coimmunoprecipitates with Cav1.3 L-type Ca channel; (3) negatively regulates Cav1.3 surface expression thus resulting in decreased Cav1.3 Ca current densities. The data demonstrate a novel mechanism of modulation of Cav1.3 Ca channel by calreticulin, which may be involved in pathological settings such as autoimmune associated congenital heart block where Cav1.3 Ca channels are downregulated.
Collapse
Affiliation(s)
- Eddy Karnabi
- Cardiovascular Research Program, Department of Physiology and Pharmacology, State University of New York Downstate Medical Center, Brooklyn, USA
| | | | | | | |
Collapse
|
15
|
Diminished vision in healthy aging is associated with increased retinal L-type voltage gated calcium channel ion influx. PLoS One 2013; 8:e56340. [PMID: 23457553 PMCID: PMC3572962 DOI: 10.1371/journal.pone.0056340] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Accepted: 01/08/2013] [Indexed: 11/19/2022] Open
Abstract
Extensive evidence implicates an increase in hippocampal L-type voltage-gated calcium channel (L-VGCC) expression, and ion influx through these channels, in age-related cognitive declines. Here, we ask if this “calcium hypothesis" applies to the neuroretina: Is increased influx via L-VGCCs related to the well-documented but poorly-understood vision declines in healthy aging? In Long-Evans rats we find a significant age-related increase in ion flux through retinal L-VGCCs in vivo (manganese-enhanced MRI (MEMRI)) that are longitudinally linked with progressive vision declines (optokinetic tracking). Importantly, the degree of retinal Mn2+ uptake early in adulthood significantly predicted later visual contrast sensitivity declines. Furthermore, as in the aging hippocampus, retinal expression of a drug-insensitive L-VGCC isoform (α1D) increased – a pattern confirmed in vivo by an age-related decline in sensitivity to L-VGCC blockade. These data highlight mechanistic similarities between retinal and hippocampal aging, and raise the possibility of new treatment targets for minimizing vision loss during healthy aging.
Collapse
|
16
|
Truncation of murine CaV1.2 at Asp 1904 increases CaV1.3 expression in embryonic atrial cardiomyocytes. Pflugers Arch 2013; 465:955-64. [PMID: 23338940 DOI: 10.1007/s00424-012-1212-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2012] [Revised: 12/18/2012] [Accepted: 12/19/2012] [Indexed: 12/25/2022]
Abstract
Cardiac CaV1.2 channels play a critical role in cardiac function. It has been proposed that the carboxyl-terminal intracellular tail of the CaV1.2 channel is the target of Ca(2+)-dependent and Ca(2+)-independent regulation of the channel. Recent studies on C-terminal truncated forms of the CaV1.2 channel reported neonatal death, reduced CaV1.2 current, and failure of β-adrenergic stimulation of these channels in ventricular cardiomyocytes (CMs). Here, we used atrial CMs at embryonic day 18.5 that expressed a C-terminal truncated form of the CaV1.2 channel (Stop/Stop). Surprisingly, the atrial CMs showed robust L-type Ca(2+) currents which could be stimulated by forskolin, an activator of adenylyl cyclase. These currents exhibited a left-ward shift in the voltage-dependent activation curve and a reduced sensitivity to the Ca(2+) channel blocker isradipine as compared to currents in wild-type atrial CMs. RT-PCR analysis revealed normal levels of mRNA for the CaV1.2 channel but a twofold increase in the level of mRNA for the CaV1.3 channel in the Stop/Stop atrium as compared to wild-type atrium. A Western blot analysis indicated an increase of CaV1.3 protein in the Stop/Stop atrium. We suggest that, in contrast to Stop/Stop ventricular CMs, Stop/Stop atrial CMs can compensate the functional loss of the truncated CaV1.2 channel with an upregulation of the CaV1.3 channel.
Collapse
|
17
|
|