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Tichauer JE, Rovegno M. Role of astrocytes connexins - pannexins in acute brain injury. Neurotherapeutics 2025; 22:e00523. [PMID: 39848901 DOI: 10.1016/j.neurot.2025.e00523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2024] [Revised: 12/31/2024] [Accepted: 01/02/2025] [Indexed: 01/25/2025] Open
Abstract
Acute brain injuries (ABIs) encompass a broad spectrum of primary injuries such as ischemia, hypoxia, trauma, and hemorrhage that converge into secondary injury where some mechanisms show common determinants. In this regard, astroglial connexin and pannexin channels have been shown to play an important role. These channels are transmembrane proteins sharing similar topology and form gateways between adjacent cells named gap junctions (GJs) and pores into unopposed membranes named hemichannels (HCs). In astrocytes, GJs and HCs enable intercellular communication and have active participation in normal brain physiological processes, such as calcium waves, synapsis modulation, regional blood flow regulation, and homeostatic control of the extracellular environment, among others. However, after acute brain injury, astrocytes can change their phenotype and modify the activity of both channels and hemichannels, which can result in the amplification of danger signals, increased mediators of inflammation, and neuronal death, contributing to the expansion of brain damage and neurological deterioration. This is known as secondary brain damage. In this review, we discussed the main biological mechanism of secondary brain damage with a particular focus on astroglial connexin and pannexin participation during acute brain injuries.
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Affiliation(s)
- Juan E Tichauer
- Departamento de Medicina Intensiva, Facultad de Medicina, Pontificia Universidad Católica de Chile, Chile.
| | - Maximiliano Rovegno
- Departamento de Medicina Intensiva, Facultad de Medicina, Pontificia Universidad Católica de Chile, Chile.
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2
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Li Y, Acosta FM, Jiang JX. Gap Junctions or Hemichannel-Dependent and Independent Roles of Connexins in Fibrosis, Epithelial-Mesenchymal Transitions, and Wound Healing. Biomolecules 2023; 13:1796. [PMID: 38136665 PMCID: PMC10742173 DOI: 10.3390/biom13121796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 12/09/2023] [Accepted: 12/12/2023] [Indexed: 12/24/2023] Open
Abstract
Fibrosis initially appears as a normal response to damage, where activated fibroblasts produce large amounts of the extracellular matrix (ECM) during the wound healing process to assist in the repair of injured tissue. However, the excessive accumulation of the ECM, unresolved by remodeling mechanisms, leads to organ dysfunction. Connexins, a family of transmembrane channel proteins, are widely recognized for their major roles in fibrosis, the epithelial-mesenchymal transition (EMT), and wound healing. Efforts have been made in recent years to identify novel mediators and targets for this regulation. Connexins form gap junctions and hemichannels, mediating communications between neighboring cells and inside and outside of cells, respectively. Recent evidence suggests that connexins, beyond forming channels, possess channel-independent functions in fibrosis, the EMT, and wound healing. One crucial channel-independent function is their role as the primary functional component for cell adhesion. Other channel-independent functions of connexins involve their roles in mitochondria and exosomes. This review summarizes the latest advances in the channel-dependent and independent roles of connexins in fibrosis, the EMT, and wound healing, with a particular focus on eye diseases, emphasizing their potential as novel, promising therapeutic targets.
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Affiliation(s)
- Yuting Li
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA; (Y.L.); (F.M.A.)
- Department of Pathology, Basic Medical School, Ningxia Medical University, Yinchuan 750004, China
| | - Francisca M. Acosta
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA; (Y.L.); (F.M.A.)
| | - Jean X. Jiang
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA; (Y.L.); (F.M.A.)
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3
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Marmolejo-Garza A, Krabbendam IE, Luu MDA, Brouwer F, Trombetta-Lima M, Unal O, O'Connor SJ, Majerníková N, Elzinga CRS, Mammucari C, Schmidt M, Madesh M, Boddeke E, Dolga AM. Negative modulation of mitochondrial calcium uniporter complex protects neurons against ferroptosis. Cell Death Dis 2023; 14:772. [PMID: 38007529 PMCID: PMC10676387 DOI: 10.1038/s41419-023-06290-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 10/30/2023] [Accepted: 11/07/2023] [Indexed: 11/27/2023]
Abstract
Ferroptosis is an iron- and reactive oxygen species (ROS)-dependent form of regulated cell death, that has been implicated in Alzheimer's disease and Parkinson's disease. Inhibition of cystine/glutamate antiporter could lead to mitochondrial fragmentation, mitochondrial calcium ([Ca2+]m) overload, increased mitochondrial ROS production, disruption of the mitochondrial membrane potential (ΔΨm), and ferroptotic cell death. The observation that mitochondrial dysfunction is a characteristic of ferroptosis makes preservation of mitochondrial function a potential therapeutic option for diseases associated with ferroptotic cell death. Mitochondrial calcium levels are controlled via the mitochondrial calcium uniporter (MCU), the main entry point of Ca2+ into the mitochondrial matrix. Therefore, we have hypothesized that negative modulation of MCU complex may confer protection against ferroptosis. Here we evaluated whether the known negative modulators of MCU complex, ruthenium red (RR), its derivative Ru265, mitoxantrone (MX), and MCU-i4 can prevent mitochondrial dysfunction and ferroptotic cell death. These compounds mediated protection in HT22 cells, in human dopaminergic neurons and mouse primary cortical neurons against ferroptotic cell death. Depletion of MICU1, a [Ca2+]m gatekeeper, demonstrated that MICU is protective against ferroptosis. Taken together, our results reveal that negative modulation of MCU complex represents a therapeutic option to prevent degenerative conditions, in which ferroptosis is central to the progression of these pathologies.
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Affiliation(s)
- Alejandro Marmolejo-Garza
- Faculty of Science and Engineering, Department of Molecular Pharmacology, Groningen Research Institute of Pharmacy (GRIP), University of Groningen, 9713 AV, Groningen, The Netherlands
- Department of Biomedical Sciences of Cells & Systems, Section Molecular Neurobiology, Faculty of Medical Sciences, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Inge E Krabbendam
- Faculty of Science and Engineering, Department of Molecular Pharmacology, Groningen Research Institute of Pharmacy (GRIP), University of Groningen, 9713 AV, Groningen, The Netherlands
| | - Minh Danh Anh Luu
- Faculty of Science and Engineering, Department of Molecular Pharmacology, Groningen Research Institute of Pharmacy (GRIP), University of Groningen, 9713 AV, Groningen, The Netherlands
| | - Famke Brouwer
- Faculty of Science and Engineering, Department of Molecular Pharmacology, Groningen Research Institute of Pharmacy (GRIP), University of Groningen, 9713 AV, Groningen, The Netherlands
| | - Marina Trombetta-Lima
- Faculty of Science and Engineering, Department of Molecular Pharmacology, Groningen Research Institute of Pharmacy (GRIP), University of Groningen, 9713 AV, Groningen, The Netherlands
- Department of Biomedical Sciences of Cells & Systems, Section Molecular Neurobiology, Faculty of Medical Sciences, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Osman Unal
- Faculty of Science and Engineering, Department of Molecular Pharmacology, Groningen Research Institute of Pharmacy (GRIP), University of Groningen, 9713 AV, Groningen, The Netherlands
| | - Shane J O'Connor
- Faculty of Science and Engineering, Department of Molecular Pharmacology, Groningen Research Institute of Pharmacy (GRIP), University of Groningen, 9713 AV, Groningen, The Netherlands
| | - Naďa Majerníková
- Department of Pathology and Medical Biology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Carolina R S Elzinga
- Faculty of Science and Engineering, Department of Molecular Pharmacology, Groningen Research Institute of Pharmacy (GRIP), University of Groningen, 9713 AV, Groningen, The Netherlands
| | - Cristina Mammucari
- Department of Biomedical Sciences, University of Padua, 35131, Padua, Italy
| | - Martina Schmidt
- Faculty of Science and Engineering, Department of Molecular Pharmacology, Groningen Research Institute of Pharmacy (GRIP), University of Groningen, 9713 AV, Groningen, The Netherlands
| | - Muniswamy Madesh
- Department of Medicine/Cardiology, Center for Mitochondrial Medicine, University of Texas Health San Antonio, San Antonio, TX, 78229, USA
| | - Erik Boddeke
- Department of Biomedical Sciences of Cells & Systems, Section Molecular Neurobiology, Faculty of Medical Sciences, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Amalia M Dolga
- Faculty of Science and Engineering, Department of Molecular Pharmacology, Groningen Research Institute of Pharmacy (GRIP), University of Groningen, 9713 AV, Groningen, The Netherlands.
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Cetin-Ferra S, Francis SC, Cooper AT, Neikirk K, Marshall AG, Hinton A, Murray SA. Mitochondrial Connexins and Mitochondrial Contact Sites with Gap Junction Structure. Int J Mol Sci 2023; 24:ijms24109036. [PMID: 37240383 DOI: 10.3390/ijms24109036] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Revised: 05/16/2023] [Accepted: 05/16/2023] [Indexed: 05/28/2023] Open
Abstract
Mitochondria contain connexins, a family of proteins that is known to form gap junction channels. Connexins are synthesized in the endoplasmic reticulum and oligomerized in the Golgi to form hemichannels. Hemichannels from adjacent cells dock with one another to form gap junction channels that aggregate into plaques and allow cell-cell communication. Cell-cell communication was once thought to be the only function of connexins and their gap junction channels. In the mitochondria, however, connexins have been identified as monomers and assembled into hemichannels, thus questioning their role solely as cell-cell communication channels. Accordingly, mitochondrial connexins have been suggested to play critical roles in the regulation of mitochondrial functions, including potassium fluxes and respiration. However, while much is known about plasma membrane gap junction channel connexins, the presence and function of mitochondrial connexins remain poorly understood. In this review, the presence and role of mitochondrial connexins and mitochondrial/connexin-containing structure contact sites will be discussed. An understanding of the significance of mitochondrial connexins and their connexin contact sites is essential to our knowledge of connexins' functions in normal and pathological conditions, and this information may aid in the development of therapeutic interventions in diseases linked to mitochondria.
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Affiliation(s)
- Selma Cetin-Ferra
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Sharon C Francis
- Department of Physiology, Morehouse School of Medicine, Atlanta, GA 30310, USA
| | - Anthonya T Cooper
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Kit Neikirk
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN 37232, USA
- Department of Biology, University of Hawaii, Hilo, HI 96720, USA
| | - Andrea G Marshall
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN 37232, USA
| | - Antentor Hinton
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN 37232, USA
| | - Sandra A Murray
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
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Zhang J, Riquelme MA, Hua R, Acosta FM, Gu S, Jiang JX. Connexin 43 hemichannels regulate mitochondrial ATP generation, mobilization, and mitochondrial homeostasis against oxidative stress. eLife 2022; 11:e82206. [PMID: 36346745 PMCID: PMC9642995 DOI: 10.7554/elife.82206] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 10/25/2022] [Indexed: 11/09/2022] Open
Abstract
Oxidative stress is a major risk factor that causes osteocyte cell death and bone loss. Prior studies primarily focus on the function of cell surface expressed Cx43 channels. Here, we reported a new role of mitochondrial Cx43 (mtCx43) and hemichannels (HCs) in modulating mitochondria homeostasis and function in bone osteocytes under oxidative stress. In murine long bone osteocyte-Y4 cells, the translocation of Cx43 to mitochondria was increased under H2O2-induced oxidative stress. H2O2 increased the mtCx43 level accompanied by elevated mtCx43 HC activity, determined by dye uptake assay. Cx43 knockdown (KD) by the CRISPR-Cas9 lentivirus system resulted in impairment of mitochondrial function, primarily manifested as decreased ATP production. Cx43 KD had reduced intracellular reactive oxidative species levels and mitochondrial membrane potential. Additionally, live-cell imaging results demonstrated that the proton flux was dependent on mtCx43 HCs because its activity was specifically inhibited by an antibody targeting Cx43 C-terminus. The co-localization and interaction of mtCx43 and ATP synthase subunit F (ATP5J2) were confirmed by Förster resonance energy transfer and a protein pull-down assay. Together, our study suggests that mtCx43 HCs regulate mitochondrial ATP generation by mediating K+, H+, and ATP transfer across the mitochondrial inner membrane and the interaction with mitochondrial ATP synthase, contributing to the maintenance of mitochondrial redox levels in response to oxidative stress.
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Affiliation(s)
- Jingruo Zhang
- Department of Biochemistry and Structural Biology, University of Texas Health Science CenterSan AntonioUnited States
| | - Manuel A Riquelme
- Department of Biochemistry and Structural Biology, University of Texas Health Science CenterSan AntonioUnited States
| | - Rui Hua
- Department of Biochemistry and Structural Biology, University of Texas Health Science CenterSan AntonioUnited States
| | - Francisca M Acosta
- Department of Biochemistry and Structural Biology, University of Texas Health Science CenterSan AntonioUnited States
| | - Sumin Gu
- Department of Biochemistry and Structural Biology, University of Texas Health Science CenterSan AntonioUnited States
| | - Jean X Jiang
- Department of Biochemistry and Structural Biology, University of Texas Health Science CenterSan AntonioUnited States
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Boengler K, Leybaert L, Ruiz-Meana M, Schulz R. Connexin 43 in Mitochondria: What Do We Really Know About Its Function? Front Physiol 2022; 13:928934. [PMID: 35860665 PMCID: PMC9289461 DOI: 10.3389/fphys.2022.928934] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 05/26/2022] [Indexed: 01/04/2023] Open
Abstract
Connexins are known for their ability to mediate cell-cell communication via gap junctions and also form hemichannels that pass ions and molecules over the plasma membrane when open. Connexins have also been detected within mitochondria, with mitochondrial connexin 43 (Cx43) being the best studied to date. In this review, we discuss evidence for Cx43 presence in mitochondria of cell lines, primary cells and organs and summarize data on its localization, import and phosphorylation status. We further highlight the influence of Cx43 on mitochondrial function in terms of respiration, opening of the mitochondrial permeability transition pore and formation of reactive oxygen species, and also address the presence of a truncated form of Cx43 termed Gja1-20k. Finally, the role of mitochondrial Cx43 in pathological conditions, particularly in the heart, is discussed.
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Affiliation(s)
- Kerstin Boengler
- Institute of Physiology, Justus-Liebig University, Giessen, Germany
| | - Luc Leybaert
- Department of Basic and Applied Medical Sciences—Physiology Group, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium
| | - Marisol Ruiz-Meana
- Cardiovascular Diseases Research Group, Vall d’Hebron Institut de Recerca (VHIR), Vall d’Hebron Hospital Universitari, Barcelona, Spain
| | - Rainer Schulz
- Institute of Physiology, Justus-Liebig University, Giessen, Germany
- *Correspondence: Rainer Schulz,
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Activation of Cx43 Hemichannels Induces the Generation of Ca 2+ Oscillations in White Adipocytes and Stimulates Lipolysis. Int J Mol Sci 2021; 22:ijms22158095. [PMID: 34360859 PMCID: PMC8347185 DOI: 10.3390/ijms22158095] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 07/22/2021] [Accepted: 07/26/2021] [Indexed: 12/11/2022] Open
Abstract
The aim of the study was to investigate the mechanisms of Ca2+ oscillation generation upon activation of connexin-43 and regulation of the lipolysis/lipogenesis balance in white adipocytes through vesicular ATP release. With fluorescence microscopy it was revealed that a decrease in the concentration of extracellular calcium ([Ca2+]ex) results in two types of Ca2+ responses in white adipocytes: Ca2+ oscillations and transient Ca2+ signals. It was found that activation of the connexin half-channels is involved in the generation of Ca2+ oscillations, since the blockers of the connexin hemichannels-carbenoxolone, octanol, proadifen and Gap26-as well as Cx43 gene knockdown led to complete suppression of these signals. The activation of Cx43 in response to the reduction of [Ca2+]ex was confirmed by TIRF microscopy. It was shown that in response to the activation of Cx43, ATP-containing vesicles were released from the adipocytes. This process was suppressed by knockdown of the Cx43 gene and by bafilomycin A1, an inhibitor of vacuolar ATPase. At the level of intracellular signaling, the generation of Ca2+ oscillations in white adipocytes in response to a decrease in [Ca2+]ex occurred due to the mobilization of the Ca2+ ions from the thapsigargin-sensitive Ca2+ pool of IP3R as a result of activation of the purinergic P2Y1 receptors and phosphoinositide signaling pathway. After activation of Cx43 and generation of the Ca2+ oscillations, changes in the expression levels of key genes and their encoding proteins involved in the regulation of lipolysis were observed in white adipocytes. This effect was accompanied by a decrease in the number of adipocytes containing lipid droplets, while inhibition or knockdown of Cx43 led to inhibition of lipolysis and accumulation of lipid droplets. In this study, we investigated the mechanism of Ca2+ oscillation generation in white adipocytes in response to a decrease in the concentration of Ca2+ ions in the external environment and established an interplay between periodic Ca2+ modes and the regulation of the lipolysis/lipogenesis balance.
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Martins-Marques T, Rodriguez-Sinovas A, Girao H. Cellular crosstalk in cardioprotection: Where and when do reactive oxygen species play a role? Free Radic Biol Med 2021; 169:397-409. [PMID: 33892116 DOI: 10.1016/j.freeradbiomed.2021.03.044] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2021] [Revised: 03/14/2021] [Accepted: 03/25/2021] [Indexed: 12/16/2022]
Abstract
A well-balanced intercellular communication between the different cells within the heart is vital for the maintenance of cardiac homeostasis and function. Despite remarkable advances on disease management and treatment, acute myocardial infarction remains the major cause of morbidity and mortality worldwide. Gold standard reperfusion strategies, namely primary percutaneous coronary intervention, are crucial to preserve heart function. However, reestablishment of blood flow and oxygen levels to the infarcted area are also associated with an accumulation of reactive oxygen species (ROS), leading to oxidative damage and cardiomyocyte death, a phenomenon termed myocardial reperfusion injury. In addition, ROS signaling has been demonstrated to regulate multiple biological pathways, including cell differentiation and intercellular communication. Given the importance of cell-cell crosstalk in the coordinated response after cell injury, in this review, we will discuss the impact of ROS in the different forms of inter- and intracellular communication, as well as the role of gap junctions, tunneling nanotubes and extracellular vesicles in the propagation of oxidative damage in cardiac diseases, particularly in the context of ischemia/reperfusion injury.
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Affiliation(s)
- Tania Martins-Marques
- Univ Coimbra, Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, Coimbra, Portugal; Univ Coimbra, Center for Innovative Biomedicine and Biotechnology (CIBB), Coimbra, Portugal; Clinical Academic Centre of Coimbra (CACC), Coimbra, Portugal
| | - Antonio Rodriguez-Sinovas
- Cardiovascular Diseases Research Group, Department of Cardiology, Vall D'Hebron Institut de Recerca (VHIR), Vall D'Hebron Hospital Universitari, Vall D'Hebron Barcelona Hospital Campus, Passeig Vall D'Hebron, 119-129, 08035, Barcelona, Spain; Departament de Medicina, Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain; Centro de Investigación Biomédica en Red Sobre Enfermedades Cardiovasculares (CIBERCV), Madrid, Spain
| | - Henrique Girao
- Univ Coimbra, Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, Coimbra, Portugal; Univ Coimbra, Center for Innovative Biomedicine and Biotechnology (CIBB), Coimbra, Portugal; Clinical Academic Centre of Coimbra (CACC), Coimbra, Portugal.
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9
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Connexins in the Heart: Regulation, Function and Involvement in Cardiac Disease. Int J Mol Sci 2021; 22:ijms22094413. [PMID: 33922534 PMCID: PMC8122935 DOI: 10.3390/ijms22094413] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 04/12/2021] [Accepted: 04/20/2021] [Indexed: 12/20/2022] Open
Abstract
Connexins are a family of transmembrane proteins that play a key role in cardiac physiology. Gap junctional channels put into contact the cytoplasms of connected cardiomyocytes, allowing the existence of electrical coupling. However, in addition to this fundamental role, connexins are also involved in cardiomyocyte death and survival. Thus, chemical coupling through gap junctions plays a key role in the spreading of injury between connected cells. Moreover, in addition to their involvement in cell-to-cell communication, mounting evidence indicates that connexins have additional gap junction-independent functions. Opening of unopposed hemichannels, located at the lateral surface of cardiomyocytes, may compromise cell homeostasis and may be involved in ischemia/reperfusion injury. In addition, connexins located at non-canonical cell structures, including mitochondria and the nucleus, have been demonstrated to be involved in cardioprotection and in regulation of cell growth and differentiation. In this review, we will provide, first, an overview on connexin biology, including their synthesis and degradation, their regulation and their interactions. Then, we will conduct an in-depth examination of the role of connexins in cardiac pathophysiology, including new findings regarding their involvement in myocardial ischemia/reperfusion injury, cardiac fibrosis, gene transcription or signaling regulation.
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Wang X, Feng L, Xin M, Hao Y, Wang X, Shang P, Zhao M, Hou S, Zhang Y, Xiao Y, Ma D, Feng J. Mechanisms underlying astrocytic connexin-43 autophagy degradation during cerebral ischemia injury and the effect on neuroinflammation and cell apoptosis. Biomed Pharmacother 2020; 127:110125. [PMID: 32361163 DOI: 10.1016/j.biopha.2020.110125] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 03/18/2020] [Accepted: 03/27/2020] [Indexed: 12/26/2022] Open
Abstract
Connexin-43 (Cx43) is the most abundant gap junction protein in the nervous system. It enables cell communication and has important physiological roles including ion transport and substrate exchange, all of which have been implicated in cerebral ischemia injury. Our previous in vitro and in vivo studies have demonstrated that Cx43 is internalized and degraded during ischemia stress. However, the significance of ischemia-induced degradation of Cx43 remains unclear. Herein, we demonstrated that Cx43 degradation during ischemia injury is mediated by selective autophagy; additionally, we identified two related autophagy receptors-OPTN and NDP52. Cx43 degradation during ischemia requires its phosphorylation and ubiquitination, which are mediated by PKC, Src kinases, and ubiquitin kinase PINK1. Using point mutagenesis, we identified three phosphorylation sites underlying Cx43 autophagy degradation under ischemic stress. Cx43 degradation inhibition promoted the transition of astrocytes from a pro-inflammatory to an anti-inflammatory status, based on the levels of IL-10 and TNF in ischemia. Knockdown or accelerated degradation of Cx43 protected astrocytes from apoptosis under ischemic stress. These findings elucidate the underlying mechanism of astrocytic Cx43 autophagic degradation during ischemia. The study has identified potentially novel therapeutic strategies against ischemic stroke and evidence of crosstalk between autophagic degradation of Cx43, astrocytic apoptosis, and neuroinflammation.
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Affiliation(s)
- Xinyu Wang
- Department of Neurology, The First Hospital of Jilin University, Changchun 130021, China
| | - Liangshu Feng
- Department of Neurology, The First Hospital of Jilin University, Changchun 130021, China
| | - Meiying Xin
- Department of Neurology, The First Hospital of Jilin University, Changchun 130021, China
| | - Yulei Hao
- Department of Neurology, The First Hospital of Jilin University, Changchun 130021, China
| | - Xu Wang
- Department of Neurology, The First Hospital of Jilin University, Changchun 130021, China
| | - Pei Shang
- Department of Neurology, The First Hospital of Jilin University, Changchun 130021, China
| | - Mingming Zhao
- Department of Neurology, The First Hospital of Jilin University, Changchun 130021, China
| | - Shuai Hou
- Department of Neurology, The First Hospital of Jilin University, Changchun 130021, China
| | - Yunhai Zhang
- Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, No. 88 Keling Street, Suzhou 215163, China
| | - Yun Xiao
- Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, No. 88 Keling Street, Suzhou 215163, China
| | - Di Ma
- Department of Neurology, The First Hospital of Jilin University, Changchun 130021, China.
| | - Jiachun Feng
- Department of Neurology, The First Hospital of Jilin University, Changchun 130021, China.
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11
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Ma D, Feng L, Cheng Y, Xin M, You J, Yin X, Hao Y, Cui L, Feng J. Astrocytic gap junction inhibition by carbenoxolone enhances the protective effects of ischemic preconditioning following cerebral ischemia. J Neuroinflammation 2018; 15:198. [PMID: 29976213 PMCID: PMC6034345 DOI: 10.1186/s12974-018-1230-5] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Accepted: 06/20/2018] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Stroke is the second leading cause of death worldwide and the most common cause of adult-acquired disability in many nations. Thus, attenuating the damage after ischemic injury and improving patient prognosis are of great importance. We have indicated that ischemic preconditioning (IP) can effectively reduce the damage of ischemia reperfusion and that inhibition of gap junctions may further reduce this damage. Although we confirmed that the function of gap junctions is closely associated with glutamate, we did not investigate the mechanism. In the present study, we aimed to clarify whether the blockade of cellular communication at gap junctions leads to significant reductions in the levels of glutamate released by astrocytes following cerebral ischemia. METHODS To explore this hypothesis, we utilized the specific blocking agent carbenoxolone (CBX) to inhibit the opening and internalization of connexin 43 channels in an in vitro model of oxygen-glucose deprivation/re-oxygenation (OGD/R), following IP. RESULTS OGD/R resulted in extensive astrocytic glutamate release following upregulation of hemichannel activity, thus increasing reactive oxygen species (ROS) generation and subsequent cell death. However, we observed significant increases in neuronal survival in neuron-astrocyte co-cultures that were subjected to IP prior to OGD/R. Moreover, the addition of CBX enhanced the protective effects of IP during the re-oxygenation period following OGD, by means of blocking the release of glutamate, increasing the level of the excitatory amino acid transporter 1, and downregulating glutamine expression. CONCLUSIONS Our results suggest that combined use of IP and CBX represents a novel therapeutic strategy to attenuate damage from cerebral ischemia with minimal adverse side effects.
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Affiliation(s)
- Di Ma
- Department of Neurology and Neuroscience center, The First Hospital of Jilin University, Changchun 130021, Jilin Province, People’s Republic of China
- http://www.jdyy.cn/
| | - Liangshu Feng
- Department of Neurology and Neuroscience center, The First Hospital of Jilin University, Changchun 130021, Jilin Province, People’s Republic of China
- http://www.jdyy.cn/
| | - Yingying Cheng
- Department of Neurology and Neuroscience center, The First Hospital of Jilin University, Changchun 130021, Jilin Province, People’s Republic of China
- http://www.jdyy.cn/
| | - Meiying Xin
- Department of Neurology and Neuroscience center, The First Hospital of Jilin University, Changchun 130021, Jilin Province, People’s Republic of China
- http://www.jdyy.cn/
| | - Jiulin You
- Department of Neurology and Neuroscience center, The First Hospital of Jilin University, Changchun 130021, Jilin Province, People’s Republic of China
- http://www.jdyy.cn/
| | - Xiang Yin
- Department of Neurology and Neuroscience center, The First Hospital of Jilin University, Changchun 130021, Jilin Province, People’s Republic of China
- http://www.jdyy.cn/
| | - Yulei Hao
- Department of Neurology and Neuroscience center, The First Hospital of Jilin University, Changchun 130021, Jilin Province, People’s Republic of China
- http://www.jdyy.cn/
| | - Li Cui
- Department of Neurology and Neuroscience center, The First Hospital of Jilin University, Changchun 130021, Jilin Province, People’s Republic of China
- http://www.jdyy.cn/
| | - Jiachun Feng
- Department of Neurology and Neuroscience center, The First Hospital of Jilin University, Changchun 130021, Jilin Province, People’s Republic of China
- http://www.jdyy.cn/
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12
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Romanov RA, Lasher RS, High B, Savidge LE, Lawson A, Rogachevskaja OA, Zhao H, Rogachevsky VV, Bystrova MF, Churbanov GD, Adameyko I, Harkany T, Yang R, Kidd GJ, Marambaud P, Kinnamon JC, Kolesnikov SS, Finger TE. Chemical synapses without synaptic vesicles: Purinergic neurotransmission through a CALHM1 channel-mitochondrial signaling complex. Sci Signal 2018; 11:11/529/eaao1815. [PMID: 29739879 DOI: 10.1126/scisignal.aao1815] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Conventional chemical synapses in the nervous system involve a presynaptic accumulation of neurotransmitter-containing vesicles, which fuse with the plasma membrane to release neurotransmitters that activate postsynaptic receptors. In taste buds, type II receptor cells do not have conventional synaptic features but nonetheless show regulated release of their afferent neurotransmitter, ATP, through a large-pore, voltage-gated channel, CALHM1. Immunohistochemistry revealed that CALHM1 was localized to points of contact between the receptor cells and sensory nerve fibers. Ultrastructural and super-resolution light microscopy showed that the CALHM1 channels were consistently associated with distinctive, large (1- to 2-μm) mitochondria spaced 20 to 40 nm from the presynaptic membrane. Pharmacological disruption of the mitochondrial respiratory chain limited the ability of taste cells to release ATP, suggesting that the immediate source of released ATP was the mitochondrion rather than a cytoplasmic pool of ATP. These large mitochondria may serve as both a reservoir of releasable ATP and the site of synthesis. The juxtaposition of the large mitochondria to areas of membrane displaying CALHM1 also defines a restricted compartment that limits the influx of Ca2+ upon opening of the nonselective CALHM1 channels. These findings reveal a distinctive organelle signature and functional organization for regulated, focal release of purinergic signals in the absence of synaptic vesicles.
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Affiliation(s)
- Roman A Romanov
- Institute of Cell Biophysics, Russian Academy of Science, Pushchino, Moscow Region 142290, Russia.,Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, A-1090 Vienna, Austria.,Immanuel Kant Baltic Federal University, Kaliningrad 236041, Russia
| | - Robert S Lasher
- Rocky Mountain Taste and Smell Center, Department of Cell and Developmental Biology, University Colorado School of Medicine, Aurora, CO 80045, USA
| | - Brigit High
- Rocky Mountain Taste and Smell Center, Department of Cell and Developmental Biology, University Colorado School of Medicine, Aurora, CO 80045, USA
| | - Logan E Savidge
- Rocky Mountain Taste and Smell Center, Department of Cell and Developmental Biology, University Colorado School of Medicine, Aurora, CO 80045, USA
| | - Adam Lawson
- Rocky Mountain Taste and Smell Center, Department of Cell and Developmental Biology, University Colorado School of Medicine, Aurora, CO 80045, USA
| | - Olga A Rogachevskaja
- Institute of Cell Biophysics, Russian Academy of Science, Pushchino, Moscow Region 142290, Russia
| | - Haitian Zhao
- Litwin-Zucker Research Center for the Study of Alzheimer's Disease, The Feinstein Institute for Medical Research, Manhasset, NY 11030, USA
| | - Vadim V Rogachevsky
- Institute of Cell Biophysics, Russian Academy of Science, Pushchino, Moscow Region 142290, Russia.,United Pushchino Center for Electron Microscopy, Pushchino, Moscow Region 142290, Russia
| | - Marina F Bystrova
- Institute of Cell Biophysics, Russian Academy of Science, Pushchino, Moscow Region 142290, Russia
| | - Gleb D Churbanov
- Institute of Cell Biophysics, Russian Academy of Science, Pushchino, Moscow Region 142290, Russia
| | - Igor Adameyko
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, A-1090 Vienna, Austria.,Department of Physiology and Pharmacology, Karolinska Institutet, SE-17177 Stockholm, Sweden
| | - Tibor Harkany
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, A-1090 Vienna, Austria.,Department of Neuroscience, Karolinska Institutet, SE-17177 Stockholm, Sweden
| | - Ruibiao Yang
- Rocky Mountain Taste and Smell Center, Department of Cell and Developmental Biology, University Colorado School of Medicine, Aurora, CO 80045, USA
| | - Grahame J Kidd
- Department of Neuroscience, Lerner Research Institute, Cleveland Clinic, and 3D-Electron Microscopy, Renovo Neural Inc., Cleveland, OH 44195, USA
| | - Philippe Marambaud
- Litwin-Zucker Research Center for the Study of Alzheimer's Disease, The Feinstein Institute for Medical Research, Manhasset, NY 11030, USA
| | - John C Kinnamon
- Rocky Mountain Taste and Smell Center, Department of Biological Sciences, University of Denver, Denver, CO 80210, USA
| | - Stanislav S Kolesnikov
- Institute of Cell Biophysics, Russian Academy of Science, Pushchino, Moscow Region 142290, Russia.
| | - Thomas E Finger
- Rocky Mountain Taste and Smell Center, Department of Cell and Developmental Biology, University Colorado School of Medicine, Aurora, CO 80045, USA.
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13
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Abstract
Major depressive disorder (MDD) is a chronic and debilitating illness that affects over 350 million people worldwide; however, current treatments have failed to cure or prevent the progress of depression. Increasing evidence suggests a crucial role for connexins in MDD. In this review, we have summarised recent accomplishments regarding the role of connexins, gap junctions, and hemichannels in the aetiology of MDD, and discussed the limitations of current research. A blockage of gap junctions or hemichannels induces depressive behaviour. Possible underlying mechanisms include the regulation of neurosecretory functions and synaptic activity by gap junctions and hemichannels. Gap junctions are functionally inhibited under stress conditions. Conversely, hemichannel permeability is increased. Antidepressants inhibit hemichannel permeability; however, they have contrasting effects on the function of gap junctions under normal conditions and can protect them against stress. In conclusion, the blockage of hemichannels concurrent with improvements in gap junction functionality might be potential targets for depression treatment.
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Affiliation(s)
- Cong-Yuan Xia
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica & Neuroscience Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Zhen-Zhen Wang
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica & Neuroscience Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Tohru Yamakuni
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai 980-8578, Japan
| | - Nai-Hong Chen
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica & Neuroscience Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China; College of Pharmacy, Hunan University of Chinese Medicine, Changsha, Hunan 410208, China.
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14
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Cardiotoxic Effects of Short-Term Doxorubicin Administration: Involvement of Connexin 43 in Calcium Impairment. Int J Mol Sci 2017; 18:ijms18102121. [PMID: 29019935 PMCID: PMC5666803 DOI: 10.3390/ijms18102121] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Revised: 09/29/2017] [Accepted: 10/09/2017] [Indexed: 12/12/2022] Open
Abstract
The use of Doxorubicin (DOXO), a potent antineoplastic agent, is limited by the development of cardiotoxicity. DOXO-induced cardiotoxicity is multifactorial, although alterations in calcium homeostasis, seem to be involved. Since even the Connexin43 (Cx43) plays a pivotal role in these two phenomena, in this study we have analyzed the effects of DOXO on Cx43 expression and localization. Damage caused by anthracyclines on cardiomyocytes is immediate after each injection, in the present study we used a short-term model of DOXO-induced cardiomyopathy. C57BL/6j female mice were randomly divided in groups and injected with DOXO (2 or 10 mg/kg i.p.) for 1–3 or 7 days once every other day. Cardiac function was assessed by Echocardiography. Sarco/endoplasmic reticulum Ca2+-ATPase (SERCAII) and phospholamban (PLB) expression were assessed by Western blot analysis, intracellular [Ca2+] were detected spectrofluorometrically by means of Fura-2 pentakis (acetoxymethyl) ester (FURA-2AM), and Cx43 and pCx43 expression and localization was analyzed by Western blot and confirmed by immunofluorescence analysis. DOXO induces impairment in Ca2+ homeostasis, already evident after a single administration, and affects Cx43 expression and localization. Our data suggest that DOXO-induced alterations in Ca2+ homeostasis causes in the cells the induction of compensatory mechanisms until a certain threshold, above which cardiac injury is triggered.
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15
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Roy S, Jiang JX, Li AF, Kim D. Connexin channel and its role in diabetic retinopathy. Prog Retin Eye Res 2017; 61:35-59. [PMID: 28602949 DOI: 10.1016/j.preteyeres.2017.06.001] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2017] [Revised: 05/30/2017] [Accepted: 06/02/2017] [Indexed: 12/18/2022]
Abstract
Diabetic retinopathy is the leading cause of blindness in the working age population. Unfortunately, there is no cure for this devastating ocular complication. The early stage of diabetic retinopathy is characterized by the loss of various cell types in the retina, namely endothelial cells and pericytes. As the disease progresses, vascular leakage, a clinical hallmark of diabetic retinopathy, becomes evident and may eventually lead to diabetic macular edema, the most common cause of vision loss in diabetic retinopathy. Substantial evidence indicates that the disruption of connexin-mediated cellular communication plays a critical role in the pathogenesis of diabetic retinopathy. Yet, it is unclear how altered communication via connexin channel mediated cell-to-cell and cell-to-extracellular microenvironment is linked to the development of diabetic retinopathy. Recent observations suggest the possibility that connexin hemichannels may play a role in the pathogenesis of diabetic retinopathy by allowing communication between cells and the microenvironment. Interestingly, recent studies suggest that connexin channels may be involved in regulating retinal vascular permeability. These cellular events are coordinated at least in part via connexin-mediated intercellular communication and the maintenance of retinal vascular homeostasis. This review highlights the effect of high glucose and diabetic condition on connexin channels and their impact on the development of diabetic retinopathy.
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Affiliation(s)
- Sayon Roy
- Departments of Medicine and Ophthalmology, Boston University School of Medicine, Boston, MA, United States.
| | - Jean X Jiang
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center, San Antonio, TX, United States
| | - An-Fei Li
- Department of Ophthalmology, Taipei Veterans General Hospital and National Yang-Ming University, Taipei, Taiwan
| | - Dongjoon Kim
- Departments of Medicine and Ophthalmology, Boston University School of Medicine, Boston, MA, United States
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16
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Decrock E, Hoorelbeke D, Ramadan R, Delvaeye T, De Bock M, Wang N, Krysko DV, Baatout S, Bultynck G, Aerts A, Vinken M, Leybaert L. Calcium, oxidative stress and connexin channels, a harmonious orchestra directing the response to radiotherapy treatment? BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2017; 1864:1099-1120. [DOI: 10.1016/j.bbamcr.2017.02.007] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Revised: 02/02/2017] [Accepted: 02/04/2017] [Indexed: 02/07/2023]
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17
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Mitochondrial Cx43 hemichannels contribute to mitochondrial calcium entry and cell death in the heart. Basic Res Cardiol 2017; 112:27. [PMID: 28364353 DOI: 10.1007/s00395-017-0618-1] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Accepted: 03/30/2017] [Indexed: 10/19/2022]
Abstract
Mitochondrial connexin 43 (Cx43) plays a key role in cardiac cytoprotection caused by repeated exposure to short periods of non-lethal ischemia/reperfusion, a condition known as ischemic preconditioning. Cx43 also forms calcium (Ca2+)-permeable hemichannels that may potentially lead to mitochondrial Ca2+ overload and cell death. Here, we studied the role of Cx43 in facilitating mitochondrial Ca2+ entry and investigated its downstream consequences. To that purpose, we used various connexin-targeting peptides interacting with extracellular (Gap26) and intracellular (Gap19, RRNYRRNY) Cx43 domains, and tested their effect on mitochondrial dye- and Ca2+-uptake, electrophysiological properties of plasmalemmal and mitochondrial Cx43 channels, and cell injury/cell death. Our results in isolated mice cardiac subsarcolemmal mitochondria indicate that Cx43 forms hemichannels that contribute to Ca2+ entry and may trigger permeability transition and cell injury/death. RRNYRRNY displayed the strongest effects in all assays and inhibited plasma membrane as well as mitochondrial Cx43 hemichannels. RRNYRRNY also strongly reduced the infarct size in ex vivo cardiac ischemia-reperfusion studies. These results indicate that Cx43 contributes to mitochondrial Ca2+ homeostasis and is involved in triggering cell injury/death pathways that can be inhibited by RRNYRRNY peptide.
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18
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Yulyana Y, Tovmasyan A, Ho IAW, Sia KC, Newman JP, Ng WH, Guo CM, Hui KM, Batinic-Haberle I, Lam PYP. Redox-Active Mn Porphyrin-based Potent SOD Mimic, MnTnBuOE-2-PyP(5+), Enhances Carbenoxolone-Mediated TRAIL-Induced Apoptosis in Glioblastoma Multiforme. Stem Cell Rev Rep 2016; 12:140-55. [PMID: 26454429 DOI: 10.1007/s12015-015-9628-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Glioblastoma multiforme is the most malignant tumor of the brain and is challenging to treat due to its highly invasive nature and heterogeneity. Malignant brain tumor displays high metabolic activity which perturbs its redox environment and in turn translates to high oxidative stress. Thus, pushing the oxidative stress level to achieve the maximum tolerable threshold that induces cell death is a potential strategy for cancer therapy. Previously, we have shown that gap junction inhibitor, carbenoxolone (CBX), is capable of enhancing tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) -induced apoptosis in glioma cells. Since CBX is known to induce oxidative stress, we hypothesized that the addition of another potent mediator of oxidative stress, powerful SOD mimic MnTnBuOE-2-PyP(5+) (MnBuOE), could further enhance TRAIL-driven therapeutic efficacy in glioma cells. Our results showed that combining TRAIL + CBX with MnBuOE significantly enhances cell death of glioma cell lines and this enhancement could be further potentiated by CBX pretreatment. MnBuOE-driven cytotoxicity is due to its ability to take advantage of oxidative stress imposed by CBX + TRAIL system, and enhance it in the presence of endogenous reductants, ascorbate and thiol, thereby producing cytotoxic H2O2, and in turn inducing death of glioma cells but not normal astrocytes. Most importantly, combination treatment significantly reduces viability of TRAIL-resistant Asian patient-derived glioma cells, thus demonstrating the potential clinical use of our therapeutic system. It was reported that H2O2 is involved in membrane depolarization-based sensitization of cancer cells toward TRAIL. MnBuOE is entering Clinical Trials as a normal brain radioprotector in glioma patients at Duke University increasing Clinical relevance of our studies.
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Affiliation(s)
- Yulyana Yulyana
- Laboratory of Cancer Gene Therapy, Cellular and Molecular Research Division, Humphrey Oei Institute of Cancer Research, National Cancer Centre, 11 Hospital Drive, Singapore, 169610, Singapore
| | - Artak Tovmasyan
- Department of Radiation Oncology, Duke University Medical Center, Research Drive 281b/285 MSRB I, Box 3455, Durham, NC, 27710, USA
| | - Ivy A W Ho
- Laboratory of Cancer Gene Therapy, Cellular and Molecular Research Division, Humphrey Oei Institute of Cancer Research, National Cancer Centre, 11 Hospital Drive, Singapore, 169610, Singapore.,National Neuroscience Institute, Singapore, Singapore
| | - Kian Chuan Sia
- Laboratory of Cancer Gene Therapy, Cellular and Molecular Research Division, Humphrey Oei Institute of Cancer Research, National Cancer Centre, 11 Hospital Drive, Singapore, 169610, Singapore.,National University of Singapore, Singapore, Singapore
| | - Jennifer P Newman
- Laboratory of Cancer Gene Therapy, Cellular and Molecular Research Division, Humphrey Oei Institute of Cancer Research, National Cancer Centre, 11 Hospital Drive, Singapore, 169610, Singapore
| | - Wai Hoe Ng
- Department of Neurosurgery, National Neuroscience Institute, Singapore, Singapore
| | - Chang Ming Guo
- Department of Orthopedics, Singapore General Hospital, Singapore, Singapore
| | - Kam Man Hui
- Bek Chai Heah Laboratory of Cancer Genomics, Cellular and Molecular Research Division, Humphrey Oei Institute of Cancer Research, National Cancer Centre of Singapore, Singapore, Singapore.,Cancer and Stem Cells Biology Program, Duke-NUS Graduate Medical School, Singapore, Singapore.,Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,Institute of Molecular and Cell Biology, A*STAR, Proteos, Singapore
| | - Ines Batinic-Haberle
- Department of Radiation Oncology, Duke University Medical Center, Research Drive 281b/285 MSRB I, Box 3455, Durham, NC, 27710, USA. .,Duke Cancer Institute, Duke University Medical Centre, Durham, NC, USA.
| | - Paula Y P Lam
- Laboratory of Cancer Gene Therapy, Cellular and Molecular Research Division, Humphrey Oei Institute of Cancer Research, National Cancer Centre, 11 Hospital Drive, Singapore, 169610, Singapore. .,Cancer and Stem Cells Biology Program, Duke-NUS Graduate Medical School, Singapore, Singapore. .,Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.
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19
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Neuroprotective Effect of Salvianolic Acids against Cerebral Ischemia/Reperfusion Injury. Int J Mol Sci 2016; 17:ijms17071190. [PMID: 27455249 PMCID: PMC4964559 DOI: 10.3390/ijms17071190] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Revised: 07/18/2016] [Accepted: 07/18/2016] [Indexed: 01/23/2023] Open
Abstract
This study investigated the neuroprotective effect of salvianolic acids (SA) against ischemia/reperfusion (I/R) injury, and explored whether the neuroprotection was dependent on mitochondrial connexin43 (mtCx43) via the phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) pathway. In vitro, we measured astrocyte apoptosis, mitochondrial membrane potential, and also evaluated the morphology of astrocyte mitochondria with transmission electron microscopy. In vivo, we determined the cerebral infarction volume and measured superoxide dismutase (SOD) activity and malondialdehyde (MDA) content. Additionally, mtCx43, p-mtCx43, AKT, and p-AKT levels were determined. In vitro, we found that I/R injury induced apoptosis, decreased cell mitochondrial membrane potential (MMP), and damaged mitochondrial morphology in astrocytes. In vivo, we found that I/R injury resulted in a large cerebral infarction, decreased SOD activity, and increased MDA expression. Additionally, I/R injury reduced both the p-mtCx43/mtCx43 and p-AKT/AKT ratios. We reported that both in vivo and in vitro, SA ameliorated the detrimental outcomes of the I/R. Interestingly, co-administering an inhibitor of the PI3K/AKT pathway blunted the effects of SA. SA represents a potential treatment option for cerebral infarction by up-regulating mtCx43 through the PI3K/AKT pathway.
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20
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Abstract
Doxorubicin is the highly effective anthracycline, but its clinical use is limited by cardiotoxicity and consequent dysfunction. It has been proposed that the etiology of this is related to mitochondrial dysfunction. Connexin 43 (Cx43), the principal protein building block of cardiac gap junctions and hemichannels, plays an important role in cardioprotection. Recent reports confirmed the presence of Cx43 in the mitochondria as well. In this study, the role of mitochondrial Cx43 was evaluated 3 or 6 h after Doxorubicin administration to the rat heart cell line H9c2. Pharmacological inhibition of Hsp90 demonstrated that the mitochondrial Cx43 conferred cardioprotection by reducing cytosolic and mitochondrial reactive oxygen species production, mitochondrial calcium overload and mitochondrial membrane depolarization and cytochrome c release. In conclusion, our study demonstrates that Cx43 plays an important role in the protection of cardiac cells from Doxorubicin-induced toxicity.
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21
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Hou S, Shen PP, Zhao MM, Liu XP, Xie HY, Deng F, Feng JC. Mechanism of Mitochondrial Connexin43's Protection of the Neurovascular Unit under Acute Cerebral Ischemia-Reperfusion Injury. Int J Mol Sci 2016; 17:ijms17050679. [PMID: 27164087 PMCID: PMC4881505 DOI: 10.3390/ijms17050679] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Revised: 04/27/2016] [Accepted: 04/29/2016] [Indexed: 02/08/2023] Open
Abstract
We observed mitochondrial connexin43 (mtCx43) expression under cerebral ischemia-reperfusion (I/R) injury, analyzed its regulation, and explored its protective mechanisms. Wistar rats were divided into groups based on injections received before middle cerebral artery occlusion (MCAO). Cerebral infarction volume was detected by 2,3,5-triphenyltetrazolim chloride staining, and cell apoptosis was observed by transferase dUTP nick end labeling. We used transmission electron microscopy to observe mitochondrial morphology and determined superoxide dismutase (SOD) activity and malondialdehyde (MDA) content. MtCx43, p-mtCx43, protein kinase C (PKC), and p-PKC expression were detected by Western blot. Compared with those in the IR group, cerebral infarction volumes in the carbenoxolone (CBX) and diazoxide (DZX) groups were obviously smaller, and the apoptosis indices were down-regulated. Mitochondrial morphology was damaged after I/R, especially in the IR and 5-hydroxydecanoic acid (5-HD) groups. Similarly, decreased SOD activity and increased MDA were observed after MCAO; CBX, DZX, and phorbol-12-myristate-13-acetate (PMA) reduced mitochondrial functional injury. Expression of mtCx43 and p-mtCx43 and the p-Cx43/Cx43 ratio were significantly lower in the IR group than in the sham group. These abnormalities were ameliorated by CBX, DZX, and PMA. MtCx43 may protect the neurovascular unit from acute cerebral IR injury via PKC activation induced by mitoKATP channel agonists.
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Affiliation(s)
- Shuai Hou
- Department of Neurology and Neuroscience center, the First Hospital of Jilin University, Changchun 130021, China.
| | - Ping-Ping Shen
- Department of Neurology and Neuroscience center, the First Hospital of Jilin University, Changchun 130021, China.
| | - Ming-Ming Zhao
- Department of Neurology and Neuroscience center, the First Hospital of Jilin University, Changchun 130021, China.
| | - Xiu-Ping Liu
- Department of Neurology and Neuroscience center, the First Hospital of Jilin University, Changchun 130021, China.
| | - Hong-Yan Xie
- Department of Neurology and Neuroscience center, the First Hospital of Jilin University, Changchun 130021, China.
| | - Fang Deng
- Department of Neurology and Neuroscience center, the First Hospital of Jilin University, Changchun 130021, China.
| | - Jia-Chun Feng
- Department of Neurology and Neuroscience center, the First Hospital of Jilin University, Changchun 130021, China.
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22
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Morel S, Christoffersen C, Axelsen LN, Montecucco F, Rochemont V, Frias MA, Mach F, James RW, Naus CC, Chanson M, Lampe PD, Nielsen MS, Nielsen LB, Kwak BR. Sphingosine-1-phosphate reduces ischaemia-reperfusion injury by phosphorylating the gap junction protein Connexin43. Cardiovasc Res 2016; 109:385-96. [PMID: 26762268 DOI: 10.1093/cvr/cvw004] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Accepted: 01/09/2016] [Indexed: 01/29/2023] Open
Abstract
AIM Increasing evidence points to lipoprotein composition rather than reverse cholesterol transport in the cardioprotective properties of high-density lipoproteins (HDLs). HDL binding to receptors at the surface of cardiomyocytes activates signalling pathways promoting survival, but downstream targets are largely unknown. Here, we investigate the pathways by which the sphingosine-1-phosphate (S1P) constituent of HDL limits cell death induced by cardiac ischaemia-reperfusion (I/R). METHODS AND RESULTS Apolipoprotein M (ApoM) transgenic (Apom-Tg) mice, in which plasma S1P is increased by 296%, and wild-type (WT) mice were subjected to in vivo I/R. Infarct size, neutrophil infiltration into the infarcted area, and serum Troponin I were less pronounced in Apom-Tg mice. In vitro experiments suggest that this cardioprotection depends on direct effects of S1P on cardiomyocytes, whereas leucocyte recruitment seems only indirectly affected. Importantly, short-term S1P treatment at the onset of reperfusion was sufficient to reduce I/R injury in isolated perfused hearts. Mechanistic in vitro and ex vivo studies revealed that 5 min of S1P treatment induced phosphorylation of the gap junction protein Connexin43 (Cx43) on Serine368 (S368), which was mediated by S1P2 and S1P3, but not by S1P1, receptors in cardiomyocytes. Finally, S1P-induced reduction of infarct size after ex vivo I/R was lost in hearts of mice with a truncated C-terminus of Cx43 (Cx43(K258/KO)) or in which the S368 is mutated to a non-phosphorylatable alanine (Cx43(S368A/S368A)). CONCLUSION Our study reveals an important molecular pathway by which modulating the apoM/S1P axis has a therapeutic potential in the fight against I/R injury in the heart.
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Affiliation(s)
- Sandrine Morel
- Department of Pathology and Immunology, University of Geneva, CMU, F06.2747.a, Rue Michel-Servet 1, Geneva 1211, Switzerland
| | - Christina Christoffersen
- Department of Clinical Biochemistry, Rigshospitalet, Copenhagen 2100, Denmark Department of Biomedical Sciences, Copenhagen 2200, Denmark
| | - Lene N Axelsen
- Department of Biomedical Sciences, Copenhagen 2200, Denmark The Danish National Research Foundation Centre for Cardiac Arrhythmia, Copenhagen 2200, Denmark
| | - Fabrizio Montecucco
- Department of Medical Specialties-Cardiology, University of Geneva, Geneva 1211, Switzerland
| | - Viviane Rochemont
- Department of Pathology and Immunology, University of Geneva, CMU, F06.2747.a, Rue Michel-Servet 1, Geneva 1211, Switzerland
| | - Miguel A Frias
- Department of Medical Specialties-Endocrinology, Diabetology, Hypertension and Nutrition, University of Geneva, Geneva 1211, Switzerland
| | - Francois Mach
- Department of Medical Specialties-Cardiology, University of Geneva, Geneva 1211, Switzerland
| | - Richard W James
- Department of Medical Specialties-Endocrinology, Diabetology, Hypertension and Nutrition, University of Geneva, Geneva 1211, Switzerland
| | - Christian C Naus
- Department of Cellular and Physiological Science, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Marc Chanson
- Department of Pediatrics, University of Geneva, Geneva 1211, Switzerland Department of Cell Physiology and Metabolism, University of Geneva, Geneva 1211, Switzerland
| | - Paul D Lampe
- Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Morten S Nielsen
- Department of Biomedical Sciences, Copenhagen 2200, Denmark The Danish National Research Foundation Centre for Cardiac Arrhythmia, Copenhagen 2200, Denmark
| | - Lars B Nielsen
- Department of Clinical Biochemistry, Rigshospitalet, Copenhagen 2100, Denmark Department of Biomedical Sciences, Copenhagen 2200, Denmark Department of Clinical Medicine, University of Copenhagen, Copenhagen 2100, Denmark
| | - Brenda R Kwak
- Department of Pathology and Immunology, University of Geneva, CMU, F06.2747.a, Rue Michel-Servet 1, Geneva 1211, Switzerland Department of Medical Specialties-Cardiology, University of Geneva, Geneva 1211, Switzerland
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23
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Förster D, Reiser G. Supportive or detrimental roles of P2Y receptors in brain pathology?--The two faces of P2Y receptors in stroke and neurodegeneration detected in neural cell and in animal model studies. Purinergic Signal 2015; 11:441-54. [PMID: 26407872 DOI: 10.1007/s11302-015-9471-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Accepted: 09/14/2015] [Indexed: 12/28/2022] Open
Abstract
This review describing the role of P2Y receptors in neuropathological conditions focuses on obvious differences between results demonstrating either a role in neuroprotection or in neurodegeneration, depending on in vitro and in vivo models. Such critical juxtaposition puts special emphasis on discussions of beneficial and detrimental effects of P2Y receptor agonists and antagonists in these models. The mechanisms reported to underlie the protection in vitro include increased expression of oxidoreductase genes, like carbonyl reductase and thioredoxin reductase; increased expression of inhibitor of apoptosis protein-2; extracellular signal-regulated kinase- and Akt-mediated antiapoptotic signaling; increased expression of Bcl-2 proteins, neurotrophins, neuropeptides, and growth factors; decreased Bax expression; non-amyloidogenic APP shedding; and increased neurite outgrowth in neuronal cells. Animal studies investigating the influence of P2Y receptors in middle cerebral artery occlusion (MCAO) models for stroke prove beneficial effects of P2Y receptor antagonists. In MCAO mice and rats, the application of broad-range P2 receptor antagonists decreased the infarct volume and improved neurological outcome. Moreover, antagonists of the P2Y1 receptor, one of the most abundant P2Y receptor subtypes in brain tissue, decreased neuronal loss and improved spatial memory in rats after traumatic brain injury (TBI). Currently available data show a discrepancy between in vitro and in vivo models concerning the benefits of P2Y receptor activation in pathological conditions. In vitro models demonstrate protection by P2Y receptor agonists, but in vivo P2Y receptor activation deteriorates the outcome after MCAO and controlled cortical impact brain injury, a TBI model. To broaden the scope of the review, we additionally discuss publications that demonstrate detrimental effects of P2Y receptor agonists in vitro and publications showing protective effects of agonists in vivo. All these studies help to better understand the significant role of P2Y receptors especially in stroke models and to develop pharmacological strategies for the treatment of stroke.
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Affiliation(s)
- Daniel Förster
- Otto-von-Guericke-Universität Magdeburg, Medizinische Fakultät, Institut für Neurobiochemie (Institut für Inflammation und Neurodegeneration), Leipziger Straße 44, 39120, Magdeburg, Germany
| | - Georg Reiser
- Otto-von-Guericke-Universität Magdeburg, Medizinische Fakultät, Institut für Neurobiochemie (Institut für Inflammation und Neurodegeneration), Leipziger Straße 44, 39120, Magdeburg, Germany.
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Maes M, Cogliati B, Crespo Yanguas S, Willebrords J, Vinken M. Roles of connexins and pannexins in digestive homeostasis. Cell Mol Life Sci 2015; 72:2809-21. [PMID: 26084872 DOI: 10.1007/s00018-015-1961-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Accepted: 06/11/2015] [Indexed: 12/21/2022]
Abstract
Connexin proteins are abundantly present in the digestive system. They primarily form gap junctions, which control the intercellular exchange of critical homeostasis regulators. By doing so, gap junctions drive a plethora of gastrointestinal and hepatic functional features, including gastric and gut motility, gastric acid secretion, intestinal innate immune defense, xenobiotic biotransformation, glycogenolysis, bile secretion, ammonia detoxification and plasma protein synthesis. In the last decade, it has become clear that connexin hemichannels, which are the structural precursors of gap junctions, also provide a pathway for cellular communication, namely between the cytosol and the extracellular environment. Although merely pathological functions have been described, some physiological roles have been attributed to connexin hemichannels, in particular in the modulation of colonic motility. This equally holds true for cellular channels composed of pannexins, connexin-like proteins recently identified in the intestine and the liver, which have become acknowledged key players in inflammatory processes and that have been proposed to control colonic motility, secretion and blood flow.
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Affiliation(s)
- Michaël Maes
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090, Brussels, Belgium
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Schulz R, Görge PM, Görbe A, Ferdinandy P, Lampe PD, Leybaert L. Connexin 43 is an emerging therapeutic target in ischemia/reperfusion injury, cardioprotection and neuroprotection. Pharmacol Ther 2015; 153:90-106. [PMID: 26073311 DOI: 10.1016/j.pharmthera.2015.06.005] [Citation(s) in RCA: 163] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Accepted: 05/29/2015] [Indexed: 12/22/2022]
Abstract
Connexins are widely distributed proteins in the body that are crucially important for heart and brain functions. Six connexin subunits form a connexon or hemichannel in the plasma membrane. Interactions between two hemichannels in a head-to-head arrangement result in the formation of a gap junction channel. Gap junctions are necessary to coordinate cell function by passing electrical current flow between heart and nerve cells or by allowing exchange of chemical signals and energy substrates. Apart from its localization at the sarcolemma of cardiomyocytes and brain cells, connexins are also found in the mitochondria where they are involved in the regulation of mitochondrial matrix ion fluxes and respiration. Connexin expression is affected by age and gender as well as several pathophysiological alterations such as hypertension, hypertrophy, diabetes, hypercholesterolemia, ischemia, post-myocardial infarction remodeling or heart failure, and post-translationally connexins are modified by phosphorylation/de-phosphorylation and nitros(yl)ation which can modulate channel activity. Using knockout/knockin technology as well as pharmacological approaches, one of the connexins, namely connexin 43, has been identified to be important for cardiac and brain ischemia/reperfusion injuries as well as protection from it. Therefore, the current review will focus on the importance of connexin 43 for irreversible injury of heart and brain tissues following ischemia/reperfusion and will highlight the importance of connexin 43 as an emerging therapeutic target in cardio- and neuroprotection.
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Affiliation(s)
- Rainer Schulz
- Institut für Physiologie, JustusLiebig Universität Giessen, Gießen, Germany.
| | | | - Anikó Görbe
- Cardiovascular Research Group, Department of Biochemistry, Faculty of Medicine, University of Szeged, Hungary; Pharmahungary Group, Szeged, Hungary
| | - Péter Ferdinandy
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary; Pharmahungary Group, Szeged, Hungary
| | - Paul D Lampe
- Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Luc Leybaert
- Physiology Group, Department Basic Medical Sciences, Ghent University, Belgium
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Baburina YL, Gordeeva AE, Moshkov DA, Krestinina OV, Azarashvili AA, Odinokova IV, Azarashvili TS. Interaction of myelin basic protein and 2',3'-cyclic nucleotide phosphodiesterase with mitochondria. BIOCHEMISTRY (MOSCOW) 2015; 79:555-65. [PMID: 25100014 DOI: 10.1134/s0006297914060091] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The content and distribution of myelin basic protein (MBP) isoforms (17 and 21.5 kDa) as well as 2',3'-cyclic nucleotide-3'-phosphodiesterase (CNPase) were determined in mitochondrial fractions (myelin fraction, synaptic and nonsynaptic mitochondria) obtained after separation of brain mitochondria by Percoll density gradient. All the fractions could accumulate calcium, maintain membrane potential, and initiate the opening of the permeability transition pore (mPTP) in response to calcium overloading. Native mitochondria and structural contacts between membranes of myelin and mitochondria were found in the myelin fraction associated with brain mitochondria. Using Western blot, it was shown that addition of myelin fraction associated with brain mitochondria to the suspension of liver mitochondria can lead to binding of CNPase and MBP, present in the fraction with liver mitochondria under the conditions of both closed and opened mPTP. However, induction of mPTP opening in liver mitochondria was prevented in the presence of myelin fraction associated with brain mitochondria (Ca2+ release rate was decreased 1.5-fold, calcium retention time was doubled, and swelling amplitude was 2.8-fold reduced). These results indicate possible protective properties of MBP and CNPase.
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Affiliation(s)
- Yu L Baburina
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russia.
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Artesi M, Kroonen J, Bredel M, Nguyen-Khac M, Deprez M, Schoysman L, Poulet C, Chakravarti A, Kim H, Scholtens D, Seute T, Rogister B, Bours V, Robe PA. Connexin 30 expression inhibits growth of human malignant gliomas but protects them against radiation therapy. Neuro Oncol 2014; 17:392-406. [PMID: 25155356 DOI: 10.1093/neuonc/nou215] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Accepted: 07/28/2014] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND Glioblastomas remain ominous tumors that almost invariably escape treatment. Connexins are a family of transmembrane, gap junction-forming proteins, some members of which were reported to act as tumor suppressors and to modulate cellular metabolism in response to cytotoxic stress. METHODS We analyzed the copy number and expression of the connexin (Cx)30 gene gap junction beta-6 (GJB6), as well as of its protein immunoreactivity in several public and proprietary repositories of glioblastomas, and their influence on patient survival. We evaluated the effect of the expression of this gap junction protein on the growth, DNA repair and energy metabolism, and treatment resistance of these tumors. RESULTS The GJB6 gene was deleted in 25.8% of 751 analyzed tumors and mutated in 15.8% of 158 tumors. Cx30 immunoreactivity was absent in 28.9% of 145 tumors. Restoration of Cx30 expression in human glioblastoma cells reduced their growth in vitro and as xenografts in the striatum of immunodeficient mice. Cx30 immunoreactivity was, however, found to adversely affect survival in 2 independent retrospective cohorts of glioblastoma patients. Cx30 was found in clonogenic assays to protect glioblastoma cells against radiation-induced mortality and to decrease radiation-induced DNA damage. This radioprotection correlated with a heat shock protein 90-dependent mitochondrial translocation of Cx30 following radiation and an improved ATP production following this genotoxic stress. CONCLUSION These results underline the complex relationship between potential tumor suppressors and treatment resistance in glioblastomas and single out GJB6/Cx30 as a potential biomarker and target for therapeutic intervention in these tumors.
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Affiliation(s)
- Maria Artesi
- Department of Human Genetics, CBIG/GIGA Research Center, University of Liège, Liège, Belgium (M.A., J.K., M.N.-K., L.S., C.P., V.B., P.A.R.); Department of Neurology and Neurosurgery and T. and P. Bonhenn Neuro-Oncology Laboratory, University Hospital of Utrecht, Utrecht, Netherlands (J.K., L.S., T.S., P.A.R.); Robert H. Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Chicago, Illinois (D.S.); Center for Population Health Sciences, Institute for Public Health and Medicine, Northwestern University, Chicago (D.S.); Division of Neuropathology, University Hospital of Liège, Liège, Belgium (M.D.); Division of Neurobiology, CBIG/GIGA Research Center, University Hospital of Liège, Liège, Belgium (B.R.); Department of Radiation Oncology, Arthur G James Comprehensive Cancer Center and Richard L. Solove Research Institute, The Ohio State University Medical Center, Columbus, Ohio (A.C., P.A.R.); Department of Radiation Oncology, Hazelrig-Salter Radiation Oncology Center and UAB Comprehensive Cancer Center, Birmingham, Alabama (M.B., H.K.)
| | - Jerome Kroonen
- Department of Human Genetics, CBIG/GIGA Research Center, University of Liège, Liège, Belgium (M.A., J.K., M.N.-K., L.S., C.P., V.B., P.A.R.); Department of Neurology and Neurosurgery and T. and P. Bonhenn Neuro-Oncology Laboratory, University Hospital of Utrecht, Utrecht, Netherlands (J.K., L.S., T.S., P.A.R.); Robert H. Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Chicago, Illinois (D.S.); Center for Population Health Sciences, Institute for Public Health and Medicine, Northwestern University, Chicago (D.S.); Division of Neuropathology, University Hospital of Liège, Liège, Belgium (M.D.); Division of Neurobiology, CBIG/GIGA Research Center, University Hospital of Liège, Liège, Belgium (B.R.); Department of Radiation Oncology, Arthur G James Comprehensive Cancer Center and Richard L. Solove Research Institute, The Ohio State University Medical Center, Columbus, Ohio (A.C., P.A.R.); Department of Radiation Oncology, Hazelrig-Salter Radiation Oncology Center and UAB Comprehensive Cancer Center, Birmingham, Alabama (M.B., H.K.)
| | - Markus Bredel
- Department of Human Genetics, CBIG/GIGA Research Center, University of Liège, Liège, Belgium (M.A., J.K., M.N.-K., L.S., C.P., V.B., P.A.R.); Department of Neurology and Neurosurgery and T. and P. Bonhenn Neuro-Oncology Laboratory, University Hospital of Utrecht, Utrecht, Netherlands (J.K., L.S., T.S., P.A.R.); Robert H. Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Chicago, Illinois (D.S.); Center for Population Health Sciences, Institute for Public Health and Medicine, Northwestern University, Chicago (D.S.); Division of Neuropathology, University Hospital of Liège, Liège, Belgium (M.D.); Division of Neurobiology, CBIG/GIGA Research Center, University Hospital of Liège, Liège, Belgium (B.R.); Department of Radiation Oncology, Arthur G James Comprehensive Cancer Center and Richard L. Solove Research Institute, The Ohio State University Medical Center, Columbus, Ohio (A.C., P.A.R.); Department of Radiation Oncology, Hazelrig-Salter Radiation Oncology Center and UAB Comprehensive Cancer Center, Birmingham, Alabama (M.B., H.K.)
| | - Minh Nguyen-Khac
- Department of Human Genetics, CBIG/GIGA Research Center, University of Liège, Liège, Belgium (M.A., J.K., M.N.-K., L.S., C.P., V.B., P.A.R.); Department of Neurology and Neurosurgery and T. and P. Bonhenn Neuro-Oncology Laboratory, University Hospital of Utrecht, Utrecht, Netherlands (J.K., L.S., T.S., P.A.R.); Robert H. Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Chicago, Illinois (D.S.); Center for Population Health Sciences, Institute for Public Health and Medicine, Northwestern University, Chicago (D.S.); Division of Neuropathology, University Hospital of Liège, Liège, Belgium (M.D.); Division of Neurobiology, CBIG/GIGA Research Center, University Hospital of Liège, Liège, Belgium (B.R.); Department of Radiation Oncology, Arthur G James Comprehensive Cancer Center and Richard L. Solove Research Institute, The Ohio State University Medical Center, Columbus, Ohio (A.C., P.A.R.); Department of Radiation Oncology, Hazelrig-Salter Radiation Oncology Center and UAB Comprehensive Cancer Center, Birmingham, Alabama (M.B., H.K.)
| | - Manuel Deprez
- Department of Human Genetics, CBIG/GIGA Research Center, University of Liège, Liège, Belgium (M.A., J.K., M.N.-K., L.S., C.P., V.B., P.A.R.); Department of Neurology and Neurosurgery and T. and P. Bonhenn Neuro-Oncology Laboratory, University Hospital of Utrecht, Utrecht, Netherlands (J.K., L.S., T.S., P.A.R.); Robert H. Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Chicago, Illinois (D.S.); Center for Population Health Sciences, Institute for Public Health and Medicine, Northwestern University, Chicago (D.S.); Division of Neuropathology, University Hospital of Liège, Liège, Belgium (M.D.); Division of Neurobiology, CBIG/GIGA Research Center, University Hospital of Liège, Liège, Belgium (B.R.); Department of Radiation Oncology, Arthur G James Comprehensive Cancer Center and Richard L. Solove Research Institute, The Ohio State University Medical Center, Columbus, Ohio (A.C., P.A.R.); Department of Radiation Oncology, Hazelrig-Salter Radiation Oncology Center and UAB Comprehensive Cancer Center, Birmingham, Alabama (M.B., H.K.)
| | - Laurent Schoysman
- Department of Human Genetics, CBIG/GIGA Research Center, University of Liège, Liège, Belgium (M.A., J.K., M.N.-K., L.S., C.P., V.B., P.A.R.); Department of Neurology and Neurosurgery and T. and P. Bonhenn Neuro-Oncology Laboratory, University Hospital of Utrecht, Utrecht, Netherlands (J.K., L.S., T.S., P.A.R.); Robert H. Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Chicago, Illinois (D.S.); Center for Population Health Sciences, Institute for Public Health and Medicine, Northwestern University, Chicago (D.S.); Division of Neuropathology, University Hospital of Liège, Liège, Belgium (M.D.); Division of Neurobiology, CBIG/GIGA Research Center, University Hospital of Liège, Liège, Belgium (B.R.); Department of Radiation Oncology, Arthur G James Comprehensive Cancer Center and Richard L. Solove Research Institute, The Ohio State University Medical Center, Columbus, Ohio (A.C., P.A.R.); Department of Radiation Oncology, Hazelrig-Salter Radiation Oncology Center and UAB Comprehensive Cancer Center, Birmingham, Alabama (M.B., H.K.)
| | - Christophe Poulet
- Department of Human Genetics, CBIG/GIGA Research Center, University of Liège, Liège, Belgium (M.A., J.K., M.N.-K., L.S., C.P., V.B., P.A.R.); Department of Neurology and Neurosurgery and T. and P. Bonhenn Neuro-Oncology Laboratory, University Hospital of Utrecht, Utrecht, Netherlands (J.K., L.S., T.S., P.A.R.); Robert H. Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Chicago, Illinois (D.S.); Center for Population Health Sciences, Institute for Public Health and Medicine, Northwestern University, Chicago (D.S.); Division of Neuropathology, University Hospital of Liège, Liège, Belgium (M.D.); Division of Neurobiology, CBIG/GIGA Research Center, University Hospital of Liège, Liège, Belgium (B.R.); Department of Radiation Oncology, Arthur G James Comprehensive Cancer Center and Richard L. Solove Research Institute, The Ohio State University Medical Center, Columbus, Ohio (A.C., P.A.R.); Department of Radiation Oncology, Hazelrig-Salter Radiation Oncology Center and UAB Comprehensive Cancer Center, Birmingham, Alabama (M.B., H.K.)
| | - Arnab Chakravarti
- Department of Human Genetics, CBIG/GIGA Research Center, University of Liège, Liège, Belgium (M.A., J.K., M.N.-K., L.S., C.P., V.B., P.A.R.); Department of Neurology and Neurosurgery and T. and P. Bonhenn Neuro-Oncology Laboratory, University Hospital of Utrecht, Utrecht, Netherlands (J.K., L.S., T.S., P.A.R.); Robert H. Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Chicago, Illinois (D.S.); Center for Population Health Sciences, Institute for Public Health and Medicine, Northwestern University, Chicago (D.S.); Division of Neuropathology, University Hospital of Liège, Liège, Belgium (M.D.); Division of Neurobiology, CBIG/GIGA Research Center, University Hospital of Liège, Liège, Belgium (B.R.); Department of Radiation Oncology, Arthur G James Comprehensive Cancer Center and Richard L. Solove Research Institute, The Ohio State University Medical Center, Columbus, Ohio (A.C., P.A.R.); Department of Radiation Oncology, Hazelrig-Salter Radiation Oncology Center and UAB Comprehensive Cancer Center, Birmingham, Alabama (M.B., H.K.)
| | - Hyunsoo Kim
- Department of Human Genetics, CBIG/GIGA Research Center, University of Liège, Liège, Belgium (M.A., J.K., M.N.-K., L.S., C.P., V.B., P.A.R.); Department of Neurology and Neurosurgery and T. and P. Bonhenn Neuro-Oncology Laboratory, University Hospital of Utrecht, Utrecht, Netherlands (J.K., L.S., T.S., P.A.R.); Robert H. Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Chicago, Illinois (D.S.); Center for Population Health Sciences, Institute for Public Health and Medicine, Northwestern University, Chicago (D.S.); Division of Neuropathology, University Hospital of Liège, Liège, Belgium (M.D.); Division of Neurobiology, CBIG/GIGA Research Center, University Hospital of Liège, Liège, Belgium (B.R.); Department of Radiation Oncology, Arthur G James Comprehensive Cancer Center and Richard L. Solove Research Institute, The Ohio State University Medical Center, Columbus, Ohio (A.C., P.A.R.); Department of Radiation Oncology, Hazelrig-Salter Radiation Oncology Center and UAB Comprehensive Cancer Center, Birmingham, Alabama (M.B., H.K.)
| | - Denise Scholtens
- Department of Human Genetics, CBIG/GIGA Research Center, University of Liège, Liège, Belgium (M.A., J.K., M.N.-K., L.S., C.P., V.B., P.A.R.); Department of Neurology and Neurosurgery and T. and P. Bonhenn Neuro-Oncology Laboratory, University Hospital of Utrecht, Utrecht, Netherlands (J.K., L.S., T.S., P.A.R.); Robert H. Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Chicago, Illinois (D.S.); Center for Population Health Sciences, Institute for Public Health and Medicine, Northwestern University, Chicago (D.S.); Division of Neuropathology, University Hospital of Liège, Liège, Belgium (M.D.); Division of Neurobiology, CBIG/GIGA Research Center, University Hospital of Liège, Liège, Belgium (B.R.); Department of Radiation Oncology, Arthur G James Comprehensive Cancer Center and Richard L. Solove Research Institute, The Ohio State University Medical Center, Columbus, Ohio (A.C., P.A.R.); Department of Radiation Oncology, Hazelrig-Salter Radiation Oncology Center and UAB Comprehensive Cancer Center, Birmingham, Alabama (M.B., H.K.)
| | - Tatjana Seute
- Department of Human Genetics, CBIG/GIGA Research Center, University of Liège, Liège, Belgium (M.A., J.K., M.N.-K., L.S., C.P., V.B., P.A.R.); Department of Neurology and Neurosurgery and T. and P. Bonhenn Neuro-Oncology Laboratory, University Hospital of Utrecht, Utrecht, Netherlands (J.K., L.S., T.S., P.A.R.); Robert H. Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Chicago, Illinois (D.S.); Center for Population Health Sciences, Institute for Public Health and Medicine, Northwestern University, Chicago (D.S.); Division of Neuropathology, University Hospital of Liège, Liège, Belgium (M.D.); Division of Neurobiology, CBIG/GIGA Research Center, University Hospital of Liège, Liège, Belgium (B.R.); Department of Radiation Oncology, Arthur G James Comprehensive Cancer Center and Richard L. Solove Research Institute, The Ohio State University Medical Center, Columbus, Ohio (A.C., P.A.R.); Department of Radiation Oncology, Hazelrig-Salter Radiation Oncology Center and UAB Comprehensive Cancer Center, Birmingham, Alabama (M.B., H.K.)
| | - Bernard Rogister
- Department of Human Genetics, CBIG/GIGA Research Center, University of Liège, Liège, Belgium (M.A., J.K., M.N.-K., L.S., C.P., V.B., P.A.R.); Department of Neurology and Neurosurgery and T. and P. Bonhenn Neuro-Oncology Laboratory, University Hospital of Utrecht, Utrecht, Netherlands (J.K., L.S., T.S., P.A.R.); Robert H. Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Chicago, Illinois (D.S.); Center for Population Health Sciences, Institute for Public Health and Medicine, Northwestern University, Chicago (D.S.); Division of Neuropathology, University Hospital of Liège, Liège, Belgium (M.D.); Division of Neurobiology, CBIG/GIGA Research Center, University Hospital of Liège, Liège, Belgium (B.R.); Department of Radiation Oncology, Arthur G James Comprehensive Cancer Center and Richard L. Solove Research Institute, The Ohio State University Medical Center, Columbus, Ohio (A.C., P.A.R.); Department of Radiation Oncology, Hazelrig-Salter Radiation Oncology Center and UAB Comprehensive Cancer Center, Birmingham, Alabama (M.B., H.K.)
| | - Vincent Bours
- Department of Human Genetics, CBIG/GIGA Research Center, University of Liège, Liège, Belgium (M.A., J.K., M.N.-K., L.S., C.P., V.B., P.A.R.); Department of Neurology and Neurosurgery and T. and P. Bonhenn Neuro-Oncology Laboratory, University Hospital of Utrecht, Utrecht, Netherlands (J.K., L.S., T.S., P.A.R.); Robert H. Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Chicago, Illinois (D.S.); Center for Population Health Sciences, Institute for Public Health and Medicine, Northwestern University, Chicago (D.S.); Division of Neuropathology, University Hospital of Liège, Liège, Belgium (M.D.); Division of Neurobiology, CBIG/GIGA Research Center, University Hospital of Liège, Liège, Belgium (B.R.); Department of Radiation Oncology, Arthur G James Comprehensive Cancer Center and Richard L. Solove Research Institute, The Ohio State University Medical Center, Columbus, Ohio (A.C., P.A.R.); Department of Radiation Oncology, Hazelrig-Salter Radiation Oncology Center and UAB Comprehensive Cancer Center, Birmingham, Alabama (M.B., H.K.)
| | - Pierre A Robe
- Department of Human Genetics, CBIG/GIGA Research Center, University of Liège, Liège, Belgium (M.A., J.K., M.N.-K., L.S., C.P., V.B., P.A.R.); Department of Neurology and Neurosurgery and T. and P. Bonhenn Neuro-Oncology Laboratory, University Hospital of Utrecht, Utrecht, Netherlands (J.K., L.S., T.S., P.A.R.); Robert H. Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Chicago, Illinois (D.S.); Center for Population Health Sciences, Institute for Public Health and Medicine, Northwestern University, Chicago (D.S.); Division of Neuropathology, University Hospital of Liège, Liège, Belgium (M.D.); Division of Neurobiology, CBIG/GIGA Research Center, University Hospital of Liège, Liège, Belgium (B.R.); Department of Radiation Oncology, Arthur G James Comprehensive Cancer Center and Richard L. Solove Research Institute, The Ohio State University Medical Center, Columbus, Ohio (A.C., P.A.R.); Department of Radiation Oncology, Hazelrig-Salter Radiation Oncology Center and UAB Comprehensive Cancer Center, Birmingham, Alabama (M.B., H.K.)
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Azarashvili T, Baburina Y, Grachev D, Krestinina O, Papadopoulos V, Lemasters JJ, Odinokova I, Reiser G. Carbenoxolone induces permeability transition pore opening in rat mitochondria via the translocator protein TSPO and connexin43. Arch Biochem Biophys 2014; 558:87-94. [PMID: 24995971 DOI: 10.1016/j.abb.2014.06.027] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Revised: 06/18/2014] [Accepted: 06/23/2014] [Indexed: 01/09/2023]
Abstract
Ca(2+)-induced permeability transition pore (mPTP) opening in isolated rat brain mitochondria is promoted through targeting of connexin43. After a threshold Ca(2+) load, mitochondrial membrane potential drops and efflux of accumulated Ca(2+) from the mitochondrial matrix occurs, indicating the mPTP opening. Specific antibodies were used to assess the role of the translocator protein (18kDa; TSPO) and connexin43 in swelling of isolated rat liver and brain mitochondria induced by carbenoxolone and the endogenous TSPO ligand protoporphyrin IX. Mitochondrial membrane potential, Ca(2+) transport and oxygen consumption were determined using selective electrodes. All the parameters were detected simultaneously in a chamber with the selective electrodes. The phosphorylation state of mitochondrial protein targets was assessed. We report that Ca(2+)-induced mitochondrial swelling was strengthened in the presence of both carbenoxolone and protoporphyrin IX. The carbenoxolone- and protoporphyrin IX-accelerated mPTP induction in brain mitochondria was completely prevented by antibodies specific for the mitochondrial translocator protein (TSPO). The anti-TSPO antibodies were more effective than anti-сonnexin43 antibodies. Moreover, carbenoxolone-stimulated phosphorylation of mitochondrial proteins was inhibited by anti-TSPO antibodies. Taken together, the data suggests that, in addition to acting via connexion43, carbenoxolone may exert its effect on mPTP via mitochondrial outer membrane TSPO.
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Affiliation(s)
- Tamara Azarashvili
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Institutskaya Str., Pushchino, Moscow Region 142290, Russia; Institut für Neurobiochemie, Otto-von-Guericke-Universität Magdeburg, Medizinische Fakultät, Leipziger Str. 44, 39120 Magdeburg, Germany.
| | - Yulia Baburina
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Institutskaya Str., Pushchino, Moscow Region 142290, Russia.
| | - Dmitry Grachev
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Institutskaya Str., Pushchino, Moscow Region 142290, Russia.
| | - Olga Krestinina
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Institutskaya Str., Pushchino, Moscow Region 142290, Russia.
| | - Vassilios Papadopoulos
- The Research Institute of the McGill University Health Center, 2155 Guy Street, Suite 500, Montreal, Quebec H3H 2R9, Canada.
| | - John J Lemasters
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Institutskaya Str., Pushchino, Moscow Region 142290, Russia; Department of Drug Discovery & Biomedical Sciences, Medical University of South Carolina, DD504 Drug Discovery Bldg., 70 President St., MSC 140, Charleston, SC 29425, USA; Department of Biochemistry & Molecular Biology, Medical University of South Carolina, DD504 Drug Discovery Bldg., 70 President St., MSC 140, Charleston, SC 29425, USA.
| | - Irina Odinokova
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Institutskaya Str., Pushchino, Moscow Region 142290, Russia.
| | - Georg Reiser
- Institut für Neurobiochemie, Otto-von-Guericke-Universität Magdeburg, Medizinische Fakultät, Leipziger Str. 44, 39120 Magdeburg, Germany.
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Garcia-Dorado D, Ruiz-Meana M, Rodríguez-Sinovas A. Connexin 43 phosphorylation in subsarcolemmal mitochondria: a general cardioprotective signal targeted by fibroblast growth factor-2? Cardiovasc Res 2014; 103:1-2. [PMID: 24835275 DOI: 10.1093/cvr/cvu129] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- David Garcia-Dorado
- Laboratory of Experimental Cardiology, Cardiology Department, Vall d'Hebron Research Institute, Universitat Autònoma de Barcelona, Pg. Vall d'Hebron 119-129, Barcelona 08035, Spain
| | - Marisol Ruiz-Meana
- Laboratory of Experimental Cardiology, Cardiology Department, Vall d'Hebron Research Institute, Universitat Autònoma de Barcelona, Pg. Vall d'Hebron 119-129, Barcelona 08035, Spain
| | - Antonio Rodríguez-Sinovas
- Laboratory of Experimental Cardiology, Cardiology Department, Vall d'Hebron Research Institute, Universitat Autònoma de Barcelona, Pg. Vall d'Hebron 119-129, Barcelona 08035, Spain
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Srisakuldee W, Makazan Z, Nickel BE, Zhang F, Thliveris JA, Pasumarthi KB, Kardami E. The FGF-2-triggered protection of cardiac subsarcolemmal mitochondria from calcium overload is mitochondrial connexin 43-dependent. Cardiovasc Res 2014; 103:72-80. [DOI: 10.1093/cvr/cvu066] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
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31
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Maes M, Decrock E, Cogliati B, Oliveira AG, Marques PE, Dagli MLZ, Menezes GB, Mennecier G, Leybaert L, Vanhaecke T, Rogiers V, Vinken M. Connexin and pannexin (hemi)channels in the liver. Front Physiol 2014; 4:405. [PMID: 24454290 PMCID: PMC3887319 DOI: 10.3389/fphys.2013.00405] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2013] [Accepted: 12/23/2013] [Indexed: 01/14/2023] Open
Abstract
The liver was among the first organs in which connexin proteins have been identified. Hepatocytes harbor connexin32 and connexin26, while non-parenchymal liver cells typically express connexin43. Connexins give rise to hemichannels, which dock with counterparts on adjacent cells to form gap junctions. Both hemichannels and gap junctions provide pathways for communication, via paracrine signaling or direct intercellular coupling, respectively. Over the years, hepatocellular gap junctions have been shown to regulate a number of liver-specific functions and to drive liver cell growth. In the last few years, it has become clear that connexin hemichannels are involved in liver cell death, particularly in hepatocyte apoptosis. This also holds true for hemichannels composed of pannexin1, a connexin-like protein recently identified in the liver. Moreover, pannexin1 hemichannels are key players in the regulation of hepatic inflammatory processes. The current paper provides a concise overview of the features of connexins, pannexins and their channels in the liver.
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Affiliation(s)
- Michaël Maes
- Department of Toxicology, Center for Pharmaceutical Research, Vrije Universiteit Brussel Brussels, Belgium
| | - Elke Decrock
- Physiology Group, Department of Basic Medical Sciences, Ghent University Ghent, Belgium
| | - Bruno Cogliati
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of Sao Paulo Sao Paulo, Brazil
| | - André G Oliveira
- Department of Morphology, Institute of Biological Sciences, Universidade Federal de Minas Gerais Belo Horizonte, Brazil
| | - Pedro E Marques
- Department of Morphology, Institute of Biological Sciences, Universidade Federal de Minas Gerais Belo Horizonte, Brazil
| | - Maria L Z Dagli
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of Sao Paulo Sao Paulo, Brazil
| | - Gustavo B Menezes
- Department of Morphology, Institute of Biological Sciences, Universidade Federal de Minas Gerais Belo Horizonte, Brazil
| | - Gregory Mennecier
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of Sao Paulo Sao Paulo, Brazil
| | - Luc Leybaert
- Physiology Group, Department of Basic Medical Sciences, Ghent University Ghent, Belgium
| | - Tamara Vanhaecke
- Department of Toxicology, Center for Pharmaceutical Research, Vrije Universiteit Brussel Brussels, Belgium
| | - Vera Rogiers
- Department of Toxicology, Center for Pharmaceutical Research, Vrije Universiteit Brussel Brussels, Belgium
| | - Mathieu Vinken
- Department of Toxicology, Center for Pharmaceutical Research, Vrije Universiteit Brussel Brussels, Belgium
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32
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Nielsen MS, Axelsen LN, Sorgen PL, Verma V, Delmar M, Holstein-Rathlou NH. Gap junctions. Compr Physiol 2013; 2:1981-2035. [PMID: 23723031 DOI: 10.1002/cphy.c110051] [Citation(s) in RCA: 310] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Gap junctions are essential to the function of multicellular animals, which require a high degree of coordination between cells. In vertebrates, gap junctions comprise connexins and currently 21 connexins are known in humans. The functions of gap junctions are highly diverse and include exchange of metabolites and electrical signals between cells, as well as functions, which are apparently unrelated to intercellular communication. Given the diversity of gap junction physiology, regulation of gap junction activity is complex. The structure of the various connexins is known to some extent; and structural rearrangements and intramolecular interactions are important for regulation of channel function. Intercellular coupling is further regulated by the number and activity of channels present in gap junctional plaques. The number of connexins in cell-cell channels is regulated by controlling transcription, translation, trafficking, and degradation; and all of these processes are under strict control. Once in the membrane, channel activity is determined by the conductive properties of the connexin involved, which can be regulated by voltage and chemical gating, as well as a large number of posttranslational modifications. The aim of the present article is to review our current knowledge on the structure, regulation, function, and pharmacology of gap junctions. This will be supported by examples of how different connexins and their regulation act in concert to achieve appropriate physiological control, and how disturbances of connexin function can lead to disease.
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Affiliation(s)
- Morten Schak Nielsen
- Department of Biomedical Sciences and The Danish National Research Foundation Centre for Cardiac Arrhythmia, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
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He X, Sandhu HK, Yang Y, Hua F, Belser N, Kim DH, Xia Y. Neuroprotection against hypoxia/ischemia: δ-opioid receptor-mediated cellular/molecular events. Cell Mol Life Sci 2013; 70:2291-303. [PMID: 23014992 PMCID: PMC11113157 DOI: 10.1007/s00018-012-1167-2] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2012] [Revised: 09/08/2012] [Accepted: 09/10/2012] [Indexed: 12/24/2022]
Abstract
Hypoxic/ischemic injury remains the most dreaded cause of neurological disability and mortality. Despite the humbling experiences due to lack of promising therapy, our understanding of the complex cascades underlying the neuronal insult has led to advances in basic science research. One of the most noteworthy has been the effect of opioid receptors, especially the delta-opioid receptor (DOR), on hypoxic/ischemic neurons. Our recent studies, and those of others worldwide, present strong evidence that sheds light on DOR-mediated neuroprotection in the brain, especially in the cortex. The mechanisms of DOR neuroprotection are broadly categorized as: (1) stabilization of the ionic homeostasis, (2) inhibition of excitatory transmitter release, (3) attenuation of disrupted neuronal transmission, (4) increase in antioxidant capacity, (5) regulation of intracellular pathways-inhibition of apoptotic signals and activation of pro-survival signaling, (6) regulation of specific gene and protein expression, and (7) up-regulation of endogenous opioid release and/or DOR expression. Depending upon the severity and duration of hypoxic/ischemic insult, the release of endogenous opioids and DOR expression are regulated in response to the stress, and DOR signaling acts at multiple levels to confer neuronal tolerance to harmful insult. The phenomenon of DOR neuroprotection offers a potential clue for a promising target that may have significant clinical implications in our quest for neurotherapeutics.
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Affiliation(s)
- Xiaozhou He
- The Third Clinical College of Suzhou University, Changzhou, Jiangsu China
| | - Harleen K. Sandhu
- The Vivian L Smith Department of Neurosurgery, The University of Texas Medical School at Houston, Houston, 77030 TX USA
| | - Yilin Yang
- The Third Clinical College of Suzhou University, Changzhou, Jiangsu China
| | - Fei Hua
- The Third Clinical College of Suzhou University, Changzhou, Jiangsu China
| | - Nathalee Belser
- The Vivian L Smith Department of Neurosurgery, The University of Texas Medical School at Houston, Houston, 77030 TX USA
| | - Dong H. Kim
- The Vivian L Smith Department of Neurosurgery, The University of Texas Medical School at Houston, Houston, 77030 TX USA
| | - Ying Xia
- The Vivian L Smith Department of Neurosurgery, The University of Texas Medical School at Houston, Houston, 77030 TX USA
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Sakurai T, Tsuchida M, Lampe PD, Murakami M. Cardiomyocyte FGF signaling is required for Cx43 phosphorylation and cardiac gap junction maintenance. Exp Cell Res 2013; 319:2152-65. [PMID: 23742896 DOI: 10.1016/j.yexcr.2013.05.022] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Revised: 05/22/2013] [Accepted: 05/25/2013] [Indexed: 02/06/2023]
Abstract
Cardiac remodeling resulting from impairment of myocardial integrity leads to heart failure, through still incompletely understood mechanisms. The fibroblast growth factor (FGF) system has been implicated in tissue maintenance, but its role in the adult heart is not well defined. We hypothesized that the FGF system plays a role in the maintenance of cardiac homeostasis, and the impairment of cardiomyocyte FGF signaling leads to pathological cardiac remodeling. We showed that FGF signaling is required for connexin 43 (Cx43) localization at cell-cell contacts in isolated cardiomyocytes and COS7 cells. Lack of FGF signaling led to decreased Cx43 phosphorylation at serines 325/328/330 (S325/328/330), sites known to be important for assembly of gap junctions. Cx43 instability induced by FGF inhibition was restored by the Cx43 S325/328/330 phospho-mimetic mutant, suggesting FGF-dependent phosphorylation of these sites. Consistent with these in vitro findings, cardiomyocyte-specific inhibition of FGF signaling in adult mice demonstrated mislocalization of Cx43 at intercalated discs, whereas localization of N-cadherin and desmoplakin was not affected. This led to premature death resulting from impaired cardiac remodeling. We conclude that cardiomyocyte FGF signaling is essential for cardiomyocyte homeostasis through phosphorylation of Cx43 at S325/328/330 residues which are important for the maintenance of gap junction.
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Affiliation(s)
- Takashi Sakurai
- Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, Yale University School of Medicine, New Haven, CT 06511, USA.
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35
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Sánchez JA, Rodríguez-Sinovas A, Barba I, Miró-Casas E, Fernández-Sanz C, Ruiz-Meana M, Alburquerque-Béjar JJ, García-Dorado D. Activation of RISK and SAFE pathways is not involved in the effects of Cx43 deficiency on tolerance to ischemia-reperfusion injury and preconditioning protection. Basic Res Cardiol 2013; 108:351. [PMID: 23595215 DOI: 10.1007/s00395-013-0351-3] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Revised: 03/22/2013] [Accepted: 04/09/2013] [Indexed: 10/27/2022]
Abstract
Connexin 43 (Cx43) deficiency increases myocardial tolerance to ischemia-reperfusion injury and abolishes preconditioning protection. It is not known whether modifications in baseline signaling through protective RISK or SAFE pathways or in response to preconditioning may contribute to these effects. To answer this question we used Cx43(Cre-ER(T)/fl) mice, in which Cx43 expression is abolished after 4-hydroxytamoxifen (4-OHT) administration. Isolated hearts from Cx43(Cre-ER(T)/fl) mice, or from Cx43(fl/fl) controls, treated with vehicle or 4-OHT, were submitted to global ischemia (40 min) and reperfusion. Cx43 deficiency was associated with reduced infarct size after ischemia-reperfusion (11.17 ± 3.25 % vs. 65.04 ± 3.79, 59.31 ± 5.36 and 65.40 ± 4.91, in Cx43(fl/fl) animals treated with vehicle, Cx43(fl/fl) mice treated with 4-OHT, and Cx43(Cre-ER(T)/fl) mice treated with vehicle, respectively, n = 8-9, p < 0.001). However, the ratio phosphorylated/total protein expression for Akt, ERK-1/2, GSK3β and STAT3 was not increased in normoxic samples from animals lacking Cx43. Instead, a reduction in the phosphorylation state of GSK3β was observed in Cx43-deficient mice (ratio: 0.15 ± 0.02 vs. 0.56 ± 0.11, 0.77 ± 0.15, and 0.46 ± 0.14, respectively, n = 5-6, p < 0.01). Furthermore, ischemic preconditioning (IPC, 4 cycles of 3.5 min of ischemia and 5 min of reperfusion) increased phosphorylation of ERK-1/2, GSK3β, and STAT3 in all hearts without differences between groups (n = 5-6, p < 0.05), although Cx43 deficient mice were not protected by either IPC or pharmacological preconditioning with diazoxide. Our data demonstrate that modification of RISK and SAFE signaling does not contribute to the role of Cx43 in the increased tolerance to myocardial ischemia-reperfusion injury and in preconditioning protection.
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Affiliation(s)
- Jose A Sánchez
- Laboratorio de Cardiología Experimental, Vall d'Hebron University Hospital and Research Institute, Universitat Autònoma de Barcelona, Pg. Vall d'Hebron 119-129, 08035 Barcelona, Spain
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Decrock E, De Bock M, Wang N, Gadicherla AK, Bol M, Delvaeye T, Vandenabeele P, Vinken M, Bultynck G, Krysko DV, Leybaert L. IP3, a small molecule with a powerful message. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2013; 1833:1772-86. [PMID: 23291251 DOI: 10.1016/j.bbamcr.2012.12.016] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2012] [Revised: 12/18/2012] [Accepted: 12/19/2012] [Indexed: 12/22/2022]
Abstract
Research conducted over the past two decades has provided convincing evidence that cell death, and more specifically apoptosis, can exceed single cell boundaries and can be strongly influenced by intercellular communication networks. We recently reported that gap junctions (i.e. channels directly connecting the cytoplasm of neighboring cells) composed of connexin43 or connexin26 provide a direct pathway to promote and expand cell death, and that inositol 1,4,5-trisphosphate (IP3) diffusion via these channels is crucial to provoke apoptosis in adjacent healthy cells. However, IP3 itself is not sufficient to induce cell death and additional factors appear to be necessary to create conditions in which IP3 will exert proapoptotic effects. Although IP3-evoked Ca(2+) signaling is known to be required for normal cell survival, it is also actively involved in apoptosis induction and progression. As such, it is evident that an accurate fine-tuning of this signaling mechanism is crucial for normal cell physiology, while a malfunction can lead to cell death. Here, we review the role of IP3 as an intracellular and intercellular cell death messenger, focusing on the endoplasmic reticulum-mitochondrial synapse, followed by a discussion of plausible elements that can convert IP3 from a physiological molecule to a killer substance. Finally, we highlight several pathological conditions in which anomalous intercellular IP3/Ca(2+) signaling might play a role. This article is part of a Special Issue entitled:12th European Symposium on Calcium.
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Affiliation(s)
- Elke Decrock
- Department of Basic Medical Sciences, Ghent University, Ghent, Belgium
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37
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Bell R, Beeuwkes R, Bøtker HE, Davidson S, Downey J, Garcia-Dorado D, Hausenloy DJ, Heusch G, Ibanez B, Kitakaze M, Lecour S, Mentzer R, Miura T, Opie L, Ovize M, Ruiz-Meana M, Schulz R, Shannon R, Walker M, Vinten-Johansen J, Yellon D. Trials, tribulations and speculation! Report from the 7th Biennial Hatter Cardiovascular Institute Workshop. Basic Res Cardiol 2012; 107:300. [DOI: 10.1007/s00395-012-0300-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2012] [Accepted: 09/11/2012] [Indexed: 02/05/2023]
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Lu G, Jiang S, Ashraf M, Haider KH. Subcellular preconditioning of stem cells: mito-Cx43 gene targeting is cytoprotective via shift of mitochondrial Bak and Bcl-xL balance. Regen Med 2012; 7:323-34. [PMID: 22594326 DOI: 10.2217/rme.12.13] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
AIM To achieve mitochondria-specific expression of connexin-43 (Cx43) transgene for mitochondrial preconditioning in stem cells to improve their survival post-transplantation during heart cell therapy. METHODS & RESULTS Cx43- or GFP-encoding adenoviral vectors with a mitochondrial targeting sequence were constructed for transduction of bone marrow Sca-1(+) cells (>90% transduction efficiency). Double-fluorescence immunostaining for cytochrome-c and Cx43 supported by western blotting confirmed mitochondria-specific Cx43 expression in adenoviral-mito-Cx43-transduced cells ((Cx43)Sca-1(+)). (Cx43)Sca-1(+) showed improved survival under lethal oxygen-glucose deprivation culture conditions. (Cx43)Sca-1(+) showed an increased mitochondrial Bcl-xL:Bak ratio and reduced cytochrome-c release into cytosol with concomitantly abolished caspase-3 activity. An in vivo study was performed such that 2 × 10(6) male (Cx43)Sca-1(+) or (GFP)Sca-1(+) cells were injected into a female rat model of acute myocardial infarction. DMEM-injected rats served as controls. On day 7 post-transplantation, 4.3-fold higher survival of (Cx43)Sca-1(+) cells (p < 0.05 vs control) and reduced terminal deoxynucleotidyl transferase dUTP nick end labeling positivity in the left ventricle (LV) were observed. In comparison, LV ejection fraction (40.2 ± 0.9%), LV fractional shortening (20.0 ± 1.6%) and LV end diastolic dimension (6.5 ± 0.3 mm) were observed in (GFP)Sca-1(+), and treatment with (Cx43)Sca-1(+) cells improved these parameters (47.6 ± 2.5%, p < 0.05; 27.7 ± 1.2%, p < 0.05; and 5.6 ± 0.1 mm, p < 0.05, respectively), along with concomitant reductions in infarction size (33.7 ± 2.9% vs 39.8 ± 1.4%; p < 0.05). CONCLUSION Mitochondria-targeted Cx43 expression is a novel approach to improve stem cell survival in the infarcted heart.
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Affiliation(s)
- Gang Lu
- Department of Pathology & Laboratory Medicine, University of Cincinnati, 231 Albert Sabin Way, Cincinnati, OH 45267, USA
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39
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Rodríguez-Sinovas A, Sánchez JA, Fernandez-Sanz C, Ruiz-Meana M, Garcia-Dorado D. Connexin and pannexin as modulators of myocardial injury. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2011; 1818:1962-70. [PMID: 21839721 DOI: 10.1016/j.bbamem.2011.07.041] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2011] [Revised: 07/20/2011] [Accepted: 07/28/2011] [Indexed: 01/02/2023]
Abstract
Multicellular organisms have developed a variety of mechanisms that allow communication between their cells. Whereas some of these systems, as neurotransmission or hormones, make possible communication between remote areas, direct cell-to-cell communication through specific membrane channels keep in contact neighboring cells. Direct communication between the cytoplasm of adjacent cells is achieved in vertebrates by membrane channels formed by connexins. However, in addition to allowing exchange of ions and small metabolites between the cytoplasms of adjacent cells, connexin channels also communicate the cytosol with the extracellular space, thus enabling a completely different communication system, involving activation of extracellular receptors. Recently, the demonstration of connexin at the inner mitochondrial membrane of cardiomyocytes, probably forming hemichannels, has enlarged the list of actions of connexins. Some of these mechanisms are also shared by a different family of proteins, termed pannexins. Importantly, these systems allow not only communication between healthy cells, but also play an important role during different types of injury. The aim of this review is to discuss the role played by both connexin hemichannels and pannexin channels in cell communication and injury. This article is part of a Special Issue entitled: The Communicating junctions, composition, structure and characteristics.
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Jeyaraman MM, Srisakuldee W, Nickel BE, Kardami E. Connexin43 phosphorylation and cytoprotection in the heart. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2011; 1818:2009-13. [PMID: 21763271 DOI: 10.1016/j.bbamem.2011.06.023] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2011] [Revised: 06/17/2011] [Accepted: 06/27/2011] [Indexed: 01/20/2023]
Abstract
The fundamental role played by connexins including connexin43 (Cx43) in forming intercellular communication channels (gap junctions), ensuring electrical and metabolic coupling between cells, has long been recognized and extensively investigated. There is also increasing recognition that Cx43, and other connexins, have additional roles, such as the ability to regulate cell proliferation, migration, and cytoprotection. Multiple phosphorylation sites, targets of different signaling pathways, are present at the regulatory, C-terminal domain of Cx43, and contribute to constitutive as well as transient phosphorylation Cx43 patterns, responding to ever-changing environmental stimuli and corresponding cellular needs. The present paper will focus on Cx43 in the heart, and provide an overview of the emerging recognition of a relationship between Cx43, its phosphorylation pattern, and development of resistance to injury. We will also review our recent work regarding the role of an enhanced phosphorylation state of Cx43 in cardioprotection. This article is part of a Special Issue entitled: The Communicating junctions, composition, structure and characteristics.
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Decrock E, Vinken M, Bol M, D'Herde K, Rogiers V, Vandenabeele P, Krysko DV, Bultynck G, Leybaert L. Calcium and connexin-based intercellular communication, a deadly catch? Cell Calcium 2011; 50:310-21. [PMID: 21621840 DOI: 10.1016/j.ceca.2011.05.007] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2011] [Revised: 05/03/2011] [Accepted: 05/05/2011] [Indexed: 10/18/2022]
Abstract
Ca(2+) is known as a universal messenger mediating a wide variety of cellular processes, including cell death. In fact, this ion has been proposed as the 'cell death master', not only at the intracellular but also at the intercellular level. The most direct form of intercellular spread of cell death is mediated by gap junction channels. These channels have been shown to propagate cell death as well as cell survival signals between the cytoplasm of neighbouring cells, reflecting the dual role of Ca(2+) signals, i.e. cell death versus survival. Its precursor, the unopposed hemichannel (half of a gap junction channel), has recently joined in as a toxic pore connecting the intracellular with the extracellular environment and allowing the passage of a range of substances. The biochemical nature of the so-called intercellular cell death molecule, transferred through gap junctions or released/taken up via hemichannels, remains elusive but several studies pinpoint Ca(2+) itself or its messenger inositol trisphosphate as the responsible masters in crime. Although direct evidence is still lacking, indirect data including Ca(2+) involvement in intercellular communication and cell death, and effects of intercellular communication on intracellular Ca(2+) homeostasis, support this hypothesis. In addition, hemichannels and their molecular building blocks, connexin or pannexin proteins, may exert their effects on Ca(2+)-dependent cell death at the intracellular level, independently from their channel functions. This review provides a cutting edge overview of the current knowledge and underscores the intimate connection between intercellular communication, Ca(2+) signalling and cell death.
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Affiliation(s)
- Elke Decrock
- Department of Basic Medical Sciences - Physiology Group, Faculty of Medicine and Health Sciences, Ghent University, B-9000 Ghent, Belgium
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