1
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Hansen CE, Kamermans A, Mol K, Berve K, Rodriguez-Mogeda C, Fung WK, van Het Hof B, Fontijn RD, van der Pol SMA, Michalick L, Kuebler WM, Kenkhuis B, van Roon-Mom W, Liedtke W, Engelhardt B, Kooij G, Witte ME, de Vries HE. Inflammation-induced TRPV4 channels exacerbate blood-brain barrier dysfunction in multiple sclerosis. J Neuroinflammation 2024; 21:72. [PMID: 38521959 PMCID: PMC10960997 DOI: 10.1186/s12974-024-03069-9] [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: 12/21/2023] [Accepted: 03/18/2024] [Indexed: 03/25/2024] Open
Abstract
BACKGROUND Blood-brain barrier (BBB) dysfunction and immune cell migration into the central nervous system (CNS) are pathogenic drivers of multiple sclerosis (MS). Ways to reinstate BBB function and subsequently limit neuroinflammation present promising strategies to restrict disease progression. However, to date, the molecular players directing BBB impairment in MS remain poorly understood. One suggested candidate to impact BBB function is the transient receptor potential vanilloid-type 4 ion channel (TRPV4), but its specific role in MS pathogenesis remains unclear. Here, we investigated the role of TRPV4 in BBB dysfunction in MS. MAIN TEXT In human post-mortem MS brain tissue, we observed a region-specific increase in endothelial TRPV4 expression around mixed active/inactive lesions, which coincided with perivascular microglia enrichment in the same area. Using in vitro models, we identified that microglia-derived tumor necrosis factor-α (TNFα) induced brain endothelial TRPV4 expression. Also, we found that TRPV4 levels influenced brain endothelial barrier formation via expression of the brain endothelial tight junction molecule claudin-5. In contrast, during an inflammatory insult, TRPV4 promoted a pathological endothelial molecular signature, as evidenced by enhanced expression of inflammatory mediators and cell adhesion molecules. Moreover, TRPV4 activity mediated T cell extravasation across the brain endothelium. CONCLUSION Collectively, our findings suggest a novel role for endothelial TRPV4 in MS, in which enhanced expression contributes to MS pathogenesis by driving BBB dysfunction and immune cell migration.
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Grants
- 813294 European Union´s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant (ENTRAIN)
- 813294 European Union´s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant (ENTRAIN)
- 813294 European Union´s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant (ENTRAIN)
- 813294 European Union´s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant (ENTRAIN)
- 91719305 Dutch Research Council, NWO, Vidi grant
- 91719305 Dutch Research Council, NWO, Vidi grant
- 91719305 Dutch Research Council, NWO, Vidi grant
- 18-1023MS Stichting MS Research
- 20-1106MS Stichting MS Research
- 20-1106MS Stichting MS Research
- 18-1023MS Stichting MS Research
- 20-1106MS Stichting MS Research
- 81X3100216 Deutsches Zentrum für Herz-Kreislaufforschung
- SFB-TR84 : subprojects A02 & C09, SFB-1449 subproject B01, SFB 1470 subproject A04, KU1218/9-1, KU1218/11-1, and KU1218/12-1 Deutsche Forschungsgemeinschaft
- PROVID (01KI20160A) and SYMPATH (01ZX1906A) Bundesministerium für Bildung und Forschung
- HA2016-02-02 Hersenstichting
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Affiliation(s)
- Cathrin E Hansen
- Department of Molecular Cell Biology and Immunology, Amsterdam UMC Location Vrije Universiteit Amsterdam, De Boelelaan 1117, Amsterdam, The Netherlands.
- Amsterdam Neuroscience, Amsterdam UMC, Amsterdam, The Netherlands.
- MS Center Amsterdam, Amsterdam UMC Location VU Medical Center, Amsterdam, The Netherlands.
| | - Alwin Kamermans
- Department of Molecular Cell Biology and Immunology, Amsterdam UMC Location Vrije Universiteit Amsterdam, De Boelelaan 1117, Amsterdam, The Netherlands
- Amsterdam Neuroscience, Amsterdam UMC, Amsterdam, The Netherlands
- MS Center Amsterdam, Amsterdam UMC Location VU Medical Center, Amsterdam, The Netherlands
| | - Kevin Mol
- Department of Biomedical Engineering and Physics, Amsterdam UMC Location University of Amsterdam, Meibergdreef 9, Amsterdam, The Netherlands
| | - Kristina Berve
- Theodor Kocher Institute, University of Bern, Bern, Switzerland
| | - Carla Rodriguez-Mogeda
- Department of Molecular Cell Biology and Immunology, Amsterdam UMC Location Vrije Universiteit Amsterdam, De Boelelaan 1117, Amsterdam, The Netherlands
- Amsterdam Neuroscience, Amsterdam UMC, Amsterdam, The Netherlands
- MS Center Amsterdam, Amsterdam UMC Location VU Medical Center, Amsterdam, The Netherlands
| | - Wing Ka Fung
- Department of Molecular Cell Biology and Immunology, Amsterdam UMC Location Vrije Universiteit Amsterdam, De Boelelaan 1117, Amsterdam, The Netherlands
| | - Bert van Het Hof
- Department of Molecular Cell Biology and Immunology, Amsterdam UMC Location Vrije Universiteit Amsterdam, De Boelelaan 1117, Amsterdam, The Netherlands
| | - Ruud D Fontijn
- Department of Molecular Cell Biology and Immunology, Amsterdam UMC Location Vrije Universiteit Amsterdam, De Boelelaan 1117, Amsterdam, The Netherlands
| | - Susanne M A van der Pol
- Department of Molecular Cell Biology and Immunology, Amsterdam UMC Location Vrije Universiteit Amsterdam, De Boelelaan 1117, Amsterdam, The Netherlands
| | - Laura Michalick
- Institute of Physiology, Corporate member of the Freie Universität Berlin and Humboldt Universität to Berlin, Charité-Universitätsmedizin Berlin, Berlin, Germany
- DZHK (German Centre for Cardiovascular Research), Partner Site Berlin, Berlin, Germany
| | - Wolfgang M Kuebler
- Institute of Physiology, Corporate member of the Freie Universität Berlin and Humboldt Universität to Berlin, Charité-Universitätsmedizin Berlin, Berlin, Germany
- DZHK (German Centre for Cardiovascular Research), Partner Site Berlin, Berlin, Germany
- Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada
- Departments of Surgery and Physiology, University of Toronto, Toronto, ON, Canada
| | - Boyd Kenkhuis
- Department of Human Genetics, Leiden University Medical Center Leiden, Leiden, The Netherlands
- UK Dementia Research Institute at University of Edinburgh, Edinburgh, UK
| | - Willeke van Roon-Mom
- Department of Human Genetics, Leiden University Medical Center Leiden, Leiden, The Netherlands
| | - Wolfgang Liedtke
- Department of Neurology, Duke University, Durham, NY, USA
- Department of Molecular Pathobiology, New York University College of Dentistry, New York, USA
| | | | - Gijs Kooij
- Department of Molecular Cell Biology and Immunology, Amsterdam UMC Location Vrije Universiteit Amsterdam, De Boelelaan 1117, Amsterdam, The Netherlands
- Amsterdam Neuroscience, Amsterdam UMC, Amsterdam, The Netherlands
- MS Center Amsterdam, Amsterdam UMC Location VU Medical Center, Amsterdam, The Netherlands
- Amsterdam Institute for Immunology and Infectious Diseases, Amsterdam UMC, Amsterdam, The Netherlands
| | - Maarten E Witte
- Department of Molecular Cell Biology and Immunology, Amsterdam UMC Location Vrije Universiteit Amsterdam, De Boelelaan 1117, Amsterdam, The Netherlands
- Amsterdam Neuroscience, Amsterdam UMC, Amsterdam, The Netherlands
- MS Center Amsterdam, Amsterdam UMC Location VU Medical Center, Amsterdam, The Netherlands
- Amsterdam Institute for Immunology and Infectious Diseases, Amsterdam UMC, Amsterdam, The Netherlands
| | - Helga E de Vries
- Department of Molecular Cell Biology and Immunology, Amsterdam UMC Location Vrije Universiteit Amsterdam, De Boelelaan 1117, Amsterdam, The Netherlands.
- Amsterdam Neuroscience, Amsterdam UMC, Amsterdam, The Netherlands.
- MS Center Amsterdam, Amsterdam UMC Location VU Medical Center, Amsterdam, The Netherlands.
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2
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Moccia F, Brunetti V, Soda T, Berra-Romani R, Scarpellino G. Cracking the Endothelial Calcium (Ca 2+) Code: A Matter of Timing and Spacing. Int J Mol Sci 2023; 24:16765. [PMID: 38069089 PMCID: PMC10706333 DOI: 10.3390/ijms242316765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 11/16/2023] [Accepted: 11/24/2023] [Indexed: 12/18/2023] Open
Abstract
A monolayer of endothelial cells lines the innermost surface of all blood vessels, thereby coming into close contact with every region of the body and perceiving signals deriving from both the bloodstream and parenchymal tissues. An increase in intracellular Ca2+ concentration ([Ca2+]i) is the main mechanism whereby vascular endothelial cells integrate the information conveyed by local and circulating cues. Herein, we describe the dynamics and spatial distribution of endothelial Ca2+ signals to understand how an array of spatially restricted (at both the subcellular and cellular levels) Ca2+ signals is exploited by the vascular intima to fulfill this complex task. We then illustrate how local endothelial Ca2+ signals affect the most appropriate vascular function and are integrated to transmit this information to more distant sites to maintain cardiovascular homeostasis. Vasorelaxation and sprouting angiogenesis were selected as an example of functions that are finely tuned by the variable spatio-temporal profile endothelial Ca2+ signals. We further highlighted how distinct Ca2+ signatures regulate the different phases of vasculogenesis, i.e., proliferation and migration, in circulating endothelial precursors.
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Affiliation(s)
- Francesco Moccia
- Laboratory of General Physiology, Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, 27100 Pavia, Italy; (V.B.); (G.S.)
| | - Valentina Brunetti
- Laboratory of General Physiology, Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, 27100 Pavia, Italy; (V.B.); (G.S.)
| | - Teresa Soda
- Department of Health Sciences, University of Magna Graecia, 88100 Catanzaro, Italy;
| | - Roberto Berra-Romani
- Department of Biomedicine, School of Medicine, Benemérita Universidad Autónoma de Puebla, Puebla 72410, Mexico;
| | - Giorgia Scarpellino
- Laboratory of General Physiology, Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, 27100 Pavia, Italy; (V.B.); (G.S.)
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3
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Badaoui M, Chanson M. Intercellular Communication in Airway Epithelial Cell Regeneration: Potential Roles of Connexins and Pannexins. Int J Mol Sci 2023; 24:16160. [PMID: 38003349 PMCID: PMC10671439 DOI: 10.3390/ijms242216160] [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: 09/26/2023] [Revised: 10/19/2023] [Accepted: 11/08/2023] [Indexed: 11/26/2023] Open
Abstract
Connexins and pannexins are transmembrane proteins that can form direct (gap junctions) or indirect (connexons, pannexons) intercellular communication channels. By propagating ions, metabolites, sugars, nucleotides, miRNAs, and/or second messengers, they participate in a variety of physiological functions, such as tissue homeostasis and host defense. There is solid evidence supporting a role for intercellular signaling in various pulmonary inflammatory diseases where alteration of connexin/pannexin channel functional expression occurs, thus leading to abnormal intercellular communication pathways and contributing to pathophysiological aspects, such as innate immune defense and remodeling. The integrity of the airway epithelium, which is the first line of defense against invading microbes, is established and maintained by a repair mechanism that involves processes such as proliferation, migration, and differentiation. Here, we briefly summarize current knowledge on the contribution of connexins and pannexins to necessary processes of tissue repair and speculate on their possible involvement in the shaping of the airway epithelium integrity.
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Affiliation(s)
| | - Marc Chanson
- Department of Cell Physiology & Metabolism, Faculty of Medicine, University of Geneva, 1211 Geneva, Switzerland;
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4
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De Bock M, De Smet MA, Verwaerde S, Tahiri H, Schumacher S, Van Haver V, Witschas K, Steinhäuser C, Rouach N, Vandenbroucke RE, Leybaert L. Targeting gliovascular connexins prevents inflammatory blood-brain barrier leakage and astrogliosis. JCI Insight 2022; 7:135263. [PMID: 35881483 PMCID: PMC9462469 DOI: 10.1172/jci.insight.135263] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 07/18/2022] [Indexed: 11/17/2022] Open
Abstract
The blood-brain barrier is formed by capillary endothelial cells expressing Cx37, Cx40 and Cx43, and is joined by closely apposed astrocytes expressing Cx43 and Cx30. We investigated whether connexin-targeting peptides could limit barrier leakage triggered by LPS-induced systemic inflammation in mice. Intraperitoneal LPS increased endothelial and astrocytic Cx43 expression, elevated TNFα, IL1β, IFNγ and IL6 in plasma and IL6 in the brain, and induced barrier leakage recorded over 24h. Barrier leakage was largely prevented by global Cx43 knockdown and Cx43/Cx30 double-knockout in astrocytes, slightly diminished by endothelial Cx43 knockout and not protected by global Cx30 knockout. Intravenous administration of Gap27 or Tat-Gap19 just before LPS also prevented barrier leakage, and intravenous BAPTA-AM to chelate intracellular calcium was equally effective. Patch-clamp experiments demonstrated LPS-induced Cx43 hemichannel opening in endothelial cells, which was suppressed by Gap27, Gap19 and BAPTA. LPS additionally triggered astrogliosis that was prevented by intravenous Tat-Gap19 or BAPTA-AM. Cortically applied Tat-Gap19 or BAPTA-AM to primarily target astrocytes, also strongly diminished barrier leakage. In vivo dye uptake and in vitro patch-clamp showed Cx43 hemichannel opening in astrocytes that was induced by IL6 in a calcium-dependent manner. We conclude that targeting endothelial and astrocytic connexins is a powerful approach to limit barrier failure and astrogliosis.
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Affiliation(s)
- Marijke De Bock
- Department of Basic & Applied Medical Sciences, Ghent University, Ghent, Belgium
| | - Maarten Aj De Smet
- Department of Basic & Applied Medical Sciences, Ghent University, Ghent, Belgium
| | - Stijn Verwaerde
- Department of Basic & Applied Medical Sciences, Ghent University, Ghent, Belgium
| | - Hanane Tahiri
- Department of Basic & Applied Medical Sciences, Ghent University, Ghent, Belgium
| | - Steffi Schumacher
- Department of Basic & Applied Medical Sciences, Ghent University, Ghent, Belgium
| | - Valérie Van Haver
- Department of Basic & Applied Medical Sciences, Ghent University, Ghent, Belgium
| | - Katja Witschas
- Department of Basic & Applied Medical Sciences, Ghent University, Ghent, Belgium
| | | | - Nathalie Rouach
- Center for Interdisiplinary Research in Biology (CIRB), College de France, Paris, France
| | | | - Luc Leybaert
- Department of Basic & Applied Medical Sciences, Ghent University, Ghent, Belgium
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5
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Rinaldi C, Donato L, Alibrandi S, Scimone C, D’Angelo R, Sidoti A. Oxidative Stress and the Neurovascular Unit. Life (Basel) 2021; 11:life11080767. [PMID: 34440511 PMCID: PMC8398978 DOI: 10.3390/life11080767] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 07/27/2021] [Accepted: 07/28/2021] [Indexed: 12/15/2022] Open
Abstract
The neurovascular unit (NVU) is a relatively recent concept that clearly describes the relationship between brain cells and their blood vessels. The components of the NVU, comprising different types of cells, are so interrelated and associated with each other that they are considered as a single functioning unit. For this reason, even slight disturbances in the NVU could severely affect brain homeostasis and health. In this review, we aim to describe the current state of knowledge concerning the role of oxidative stress on the neurovascular unit and the role of a single cell type in the NVU crosstalk.
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Affiliation(s)
- Carmela Rinaldi
- Department of Biomedical, Dental, Morphological and Functional Imaging Sciences, University of Messina, Via Consolare Valeria 1, 98125 Messina, Italy; (C.R.); (L.D.); (S.A.); (R.D.); (A.S.)
| | - Luigi Donato
- Department of Biomedical, Dental, Morphological and Functional Imaging Sciences, University of Messina, Via Consolare Valeria 1, 98125 Messina, Italy; (C.R.); (L.D.); (S.A.); (R.D.); (A.S.)
- Department of Biomolecular Strategies, Genetics and Avant-Garde Therapies, Istituto Euro-Mediterraneo di Scienza e Tecnologia (I.E.ME.S.T.), Via Michele Miraglia, 90139 Palermo, Italy
| | - Simona Alibrandi
- Department of Biomedical, Dental, Morphological and Functional Imaging Sciences, University of Messina, Via Consolare Valeria 1, 98125 Messina, Italy; (C.R.); (L.D.); (S.A.); (R.D.); (A.S.)
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Viale Ferdinando Stagno d’Alcontres 31, 98166 Messina, Italy
| | - Concetta Scimone
- Department of Biomedical, Dental, Morphological and Functional Imaging Sciences, University of Messina, Via Consolare Valeria 1, 98125 Messina, Italy; (C.R.); (L.D.); (S.A.); (R.D.); (A.S.)
- Department of Biomolecular Strategies, Genetics and Avant-Garde Therapies, Istituto Euro-Mediterraneo di Scienza e Tecnologia (I.E.ME.S.T.), Via Michele Miraglia, 90139 Palermo, Italy
- Correspondence:
| | - Rosalia D’Angelo
- Department of Biomedical, Dental, Morphological and Functional Imaging Sciences, University of Messina, Via Consolare Valeria 1, 98125 Messina, Italy; (C.R.); (L.D.); (S.A.); (R.D.); (A.S.)
| | - Antonina Sidoti
- Department of Biomedical, Dental, Morphological and Functional Imaging Sciences, University of Messina, Via Consolare Valeria 1, 98125 Messina, Italy; (C.R.); (L.D.); (S.A.); (R.D.); (A.S.)
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6
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Strauss RE, Gourdie RG. Cx43 and the Actin Cytoskeleton: Novel Roles and Implications for Cell-Cell Junction-Based Barrier Function Regulation. Biomolecules 2020; 10:E1656. [PMID: 33321985 PMCID: PMC7764618 DOI: 10.3390/biom10121656] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 12/07/2020] [Accepted: 12/07/2020] [Indexed: 12/13/2022] Open
Abstract
Barrier function is a vital homeostatic mechanism employed by epithelial and endothelial tissue. Diseases across a wide range of tissue types involve dynamic changes in transcellular junctional complexes and the actin cytoskeleton in the regulation of substance exchange across tissue compartments. In this review, we focus on the contribution of the gap junction protein, Cx43, to the biophysical and biochemical regulation of barrier function. First, we introduce the structure and canonical channel-dependent functions of Cx43. Second, we define barrier function and examine the key molecular structures fundamental to its regulation. Third, we survey the literature on the channel-dependent roles of connexins in barrier function, with an emphasis on the role of Cx43 and the actin cytoskeleton. Lastly, we discuss findings on the channel-independent roles of Cx43 in its associations with the actin cytoskeleton and focal adhesion structures highlighted by PI3K signaling, in the potential modulation of cellular barriers. Mounting evidence of crosstalk between connexins, the cytoskeleton, focal adhesion complexes, and junctional structures has led to a growing appreciation of how barrier-modulating mechanisms may work together to effect solute and cellular flux across tissue boundaries. This new understanding could translate into improved therapeutic outcomes in the treatment of barrier-associated diseases.
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Affiliation(s)
- Randy E. Strauss
- Virginia Tech, Translational Biology Medicine and Health (TBMH) Program, Roanoke, VA 24016, USA
| | - Robert G. Gourdie
- Center for Heart and Reparative Medicine Research, Fralin Biomedical Research Institute at Virginia Tech Carilion, Roanoke, VA 24016, USA
- Virginia Tech Carilion School of Medicine, Roanoke, VA 24016, USA
- Department of Biomedical Engineering and Mechanics, Virginia Polytechnic Institute and State University, Blacksburg, VA 24060, USA
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7
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Maruyama S, Akanuma SI, Kubo Y, Hosoya KI. Characteristics of Hemichannel-Mediated Substrate Transport in Human Retinal Pigment Epithelial Cells under Deprivation of Extracellular Ca 2. Biol Pharm Bull 2020; 43:1241-1247. [PMID: 32741944 DOI: 10.1248/bpb.b20-00290] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Retinal pigment epithelial (RPE) cells form the outer blood-retinal barrier (BRB) and regulate drug/compound exchange between the neural retina and blood in the fenestrated blood vessels of retinal choroid via membrane transporters. Recent studies have elucidated that RPE cells express hemichannels, which are opened by extracellular Ca2+ depletion and accept several drugs/compounds as a transporting substrate. The objective of this study was to elucidate the hemichannel-mediated compound transport properties of the outer BRB. In human RPE cells, namely ARPE-19 cells, time-dependent uptake of fluorescent hemichannel substrates, such as Lucifer Yellow, sulforhodamine-101 (SR-101), and propidium iodide (PI) was promoted under Ca2+-depleted conditions. The uptake of these substrates under Ca2+-depleted conditions exhibited saturable kinetics with a Michaelis-Menten constant (Km) of 87-109 µM. In addition, SR-101 and PI uptake by ARPE-19 cells was dependent of extracellular Ca2+ concentration, and that under Ca2+-depleted conditions was significantly decreased by typical substrates and/or inhibitors for hemichannels. Moreover, Ca2+-depleted conditions promoted the efflux transport of calcein from ARPE-19 cells, and the promoted calcein efflux transport was significantly inhibited by a typical hemichannel inhibitor. These results suggested that hemichannels at the outer BRB were involved in the influx and efflux transport of drugs/compounds.
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Affiliation(s)
- Souhei Maruyama
- Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama
| | - Shin-Ichi Akanuma
- Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama
| | - Yoshiyuki Kubo
- Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama
| | - Ken-Ichi Hosoya
- Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama
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8
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Ma X, Liu W. Calcium signaling in brain microvascular endothelial cells and its roles in the function of the blood-brain barrier. Neuroreport 2020; 30:1271-1277. [PMID: 31688421 DOI: 10.1097/wnr.0000000000001357] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The blood-brain barrier (BBB) plays critical roles in maintaining the stability of the brain's internal milieu, providing nutrients for the brain, and preventing toxic materials from the blood from entering the brain. The cellular structure of the BBB is mainly composed of brain microvascular endothelial cells (BMVECs), which are surrounded by astrocytic endfeet that are connected by tight junction proteins, pericytes and astrocytes. Recently, several studies have shown that aberrant increase in intracellular calcium levels in BMVECs lead to cellular metabolic disturbances and subsequent impairment of BBB integrity. Although multiple stresses can lead to intracellular calcium accumulation, inherent protective mechanisms in affected cells are subsequently activated to maintain calcium homeostasis. However, once the increase in intracellular calcium goes beyond a certain threshold, disturbances in cellular structures, protein expression, and the BBB permeability are inevitable. Here, we review recent research on the different factors regulating intracellular calcium concentrations and the mechanisms related to how calcium signaling cascades protect the BMVECs from outside injury. We also consider the potential of calcium signaling regulators as therapeutic targets for modulating intracellular calcium homeostasis and ameliorating BBB disruption in patients with calcium-related pathologies.
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Affiliation(s)
- Xingjie Ma
- Department of Intensive Care, The Affiliated Hospital of Yangzhou University, Yangzhou University, Yangzhou, China
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9
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Genova T, Gaglioti D, Munaron L. Regulation of Vessel Permeability by TRP Channels. Front Physiol 2020; 11:421. [PMID: 32431625 PMCID: PMC7214926 DOI: 10.3389/fphys.2020.00421] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Accepted: 04/07/2020] [Indexed: 12/13/2022] Open
Abstract
The vascular endothelium constitutes a semi-permeable barrier between blood and interstitial fluids. Since an augmented endothelial permeability is often associated to pathological states, understanding the molecular basis for its regulation is a crucial biomedical and clinical challenge. This review focuses on the processes controlling paracellular permeability that is the permeation of fluids between adjacent endothelial cells (ECs). Cytosolic calcium changes are often detected as early events preceding the alteration of the endothelial barrier (EB) function. For this reason, great interest has been devoted in the last decades to unveil the molecular mechanisms underlying calcium fluxes and their functional relationship with vessel permeability. Beyond the dicotomic classification between store-dependent and independent calcium entry at the plasma membrane level, the search for the molecular components of the related calcium-permeable channels revealed a difficult task for intrinsic and technical limitations. The contribution of redundant channel-forming proteins including members of TRP superfamily and Orai1, together with the very complex intracellular modulatory pathways, displays a huge variability among tissues and along the vascular tree. Moreover, calcium-independent events could significantly concur to the regulation of vascular permeability in an intricate and fascinating multifactorial framework.
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Affiliation(s)
- Tullio Genova
- Department of Life Sciences and Systems Biology, University of Turin, Turin, Italy
| | - Deborah Gaglioti
- Department of Life Sciences and Systems Biology, University of Turin, Turin, Italy
| | - Luca Munaron
- Department of Life Sciences and Systems Biology, University of Turin, Turin, Italy
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10
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Tachikawa M, Murakami K, Akaogi R, Akanuma SI, Terasaki T, Hosoya KI. Polarized hemichannel opening of pannexin 1/connexin 43 contributes to dysregulation of transport function in blood-brain barrier endothelial cells. Neurochem Int 2019; 132:104600. [PMID: 31712070 DOI: 10.1016/j.neuint.2019.104600] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2019] [Revised: 10/18/2019] [Accepted: 11/07/2019] [Indexed: 01/06/2023]
Abstract
Dysregulation of blood-brain barrier (BBB) transport exacerbates brain damage in acute ischemic stroke. Here, we aimed to investigate the mechanism of this BBB transport dysregulation by studying the localization and function of pannexin (Px) and connexin (Cx) hemichannels in blood-brain barrier endothelial cells of rat (TR-BBB13 cells) and human (hCMEC/D3 cells) under acute ischemic stroke-mimicking oxygen/glucose deprivation (OGD) and extracellular Ca2+ ([Ca2+]e)-free conditions. TR-BBB13 cells showed increased uptake of hemichannel-permeable sulforhodamine 101, and this increase was markedly inhibited by carbenoxolone, a hemichannel inhibitor. Transcripts of Px1 and Cx43 were detected in TR-BBB13 cells and freshly isolated brain microvascular endothelial cells. The basal compartment-to-cell uptake of hemichannel-permeable propidium iodide was selectively enhanced in hCMEC/D3 cells under [Ca2+]e-free conditions in the basal Transwell chamber. Immunohistochemical analysis revealed the predominant localization of Cx43 on the lateral membranes of hCMEC/D3 cells. [3H]Taurine uptake by hCMEC/D3 cells was significantly reduced in the absence of [Ca2+]e. Functional knock-down of Px1 and Cx43 with mimetic peptides significantly inhibited the increase of ATP release from hCMEC/D3 cells under [Ca2+]e-free conditions. These results suggest that polarized Px1/Cx43 hemichannel opening in brain capillary endothelial cells under acute ischemic stroke-mimicking conditions contributes to dysregulation of BBB transport function, resulting in release of intracellular taurine and ATP.
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Affiliation(s)
- Masanori Tachikawa
- Division of Membrane Transport and Drug Targeting, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan; Graduate School of Biomedical Sciences, Tokushima University, Tokushima, Japan.
| | - Koji Murakami
- Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan
| | - Ryo Akaogi
- Division of Membrane Transport and Drug Targeting, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan
| | - Shin-Ichi Akanuma
- Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan
| | - Tetsuya Terasaki
- Division of Membrane Transport and Drug Targeting, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan
| | - Ken-Ichi Hosoya
- Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan
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11
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Abudara V, Retamal MA, Del Rio R, Orellana JA. Synaptic Functions of Hemichannels and Pannexons: A Double-Edged Sword. Front Mol Neurosci 2018; 11:435. [PMID: 30564096 PMCID: PMC6288452 DOI: 10.3389/fnmol.2018.00435] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Accepted: 11/08/2018] [Indexed: 01/18/2023] Open
Abstract
The classical view of synapses as the functional contact between presynaptic and postsynaptic neurons has been challenged in recent years by the emerging regulatory role of glial cells. Astrocytes, traditionally considered merely supportive elements are now recognized as active modulators of synaptic transmission and plasticity at the now so-called "tripartite synapse." In addition, an increasing body of evidence indicates that beyond immune functions microglia also participate in various processes aimed to shape synaptic plasticity. Release of neuroactive compounds of glial origin, -process known as gliotransmission-, constitute a widespread mechanism through which glial cells can either potentiate or reduce the synaptic strength. The prevailing vision states that gliotransmission depends on an intracellular Ca2+/exocytotic-mediated release; notwithstanding, growing evidence is pointing at hemichannels (connexons) and pannexin channels (pannexons) as alternative non-vesicular routes for gliotransmitters efflux. In concurrence with this novel concept, both hemichannels and pannexons are known to mediate the transfer of ions and signaling molecules -such as ATP and glutamate- between the cytoplasm and the extracellular milieu. Importantly, recent reports show that glial hemichannels and pannexons are capable to perceive synaptic activity and to respond to it through changes in their functional state. In this article, we will review the current information supporting the "double edge sword" role of hemichannels and pannexons in the function of central and peripheral synapses. At one end, available data support the idea that these channels are chief components of a feedback control mechanism through which gliotransmitters adjust the synaptic gain in either resting or stimulated conditions. At the other end, we will discuss how the excitotoxic release of gliotransmitters and [Ca2+]i overload linked to the opening of hemichannels/pannexons might impact cell function and survival in the nervous system.
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Affiliation(s)
- Verónica Abudara
- Departamento de Fisiología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Mauricio A Retamal
- Centro de Fisiología Celular e Integrativa, Facultad de Medicina, Clínica Alemana Universidad del Desarrollo, Santiago, Chile.,Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, Texas Tech University Health Sciences Center, Lubbock, TX, United States.,Programa de Comunicación Celular en Cáncer, Instituto de Ciencias e Innovación en Medicina, Santiago, Chile
| | - Rodrigo Del Rio
- Laboratory of Cardiorespiratory Control, Departamento de Fisiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile.,Centro de Envejecimiento y Regeneración, Pontificia Universidad Católica de Chile, Santiago, Chile.,Centro de Excelencia en Biomedicina de Magallanes, Universidad de Magallanes, Punta Arenas, Chile
| | - Juan A Orellana
- Departamento de Neurología, Escuela de Medicina and Centro Interdisciplinario de Neurociencias, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile.,Centro de Investigación y Estudio del Consumo de Alcohol en Adolescentes, Santiago, Chile
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12
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Function of Connexins in the Interaction between Glial and Vascular Cells in the Central Nervous System and Related Neurological Diseases. Neural Plast 2018; 2018:6323901. [PMID: 29983707 PMCID: PMC6015683 DOI: 10.1155/2018/6323901] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 05/06/2018] [Accepted: 05/14/2018] [Indexed: 02/05/2023] Open
Abstract
Neuronal signaling together with synapse activity in the central nervous system requires a precisely regulated microenvironment. Recently, the blood-brain barrier is considered as a “neuro-glia-vascular unit,” a structural and functional compound composed of capillary endothelial cells, glial cells, pericytes, and neurons, which plays a pivotal role in maintaining the balance of the microenvironment in and out of the brain. Tight junctions and adherens junctions, which function as barriers of the blood-brain barrier, are two well-known kinds in the endothelial cell junctions. In this review, we focus on the less-concerned contribution of gap junction proteins, connexins in blood-brain barrier integrity under physio-/pathology conditions. In the neuro-glia-vascular unit, connexins are expressed in the capillary endothelial cells and prominent in astrocyte endfeet around and associated with maturation and function of the blood-brain barrier through a unique signaling pathway and an interaction with tight junction proteins. Connexin hemichannels and connexin gap junction channels contribute to the physiological or pathological progress of the blood-brain barrier; in addition, the interaction with other cell-cell-adhesive proteins is also associated with the maintenance of the blood-brain barrier. Lastly, we explore the connexins and connexin channels involved in the blood-brain barrier in neurological diseases and any programme for drug discovery or delivery to target or avoid the blood-brain barrier.
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13
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Branca JJV, Maresca M, Morucci G, Becatti M, Paternostro F, Gulisano M, Ghelardini C, Salvemini D, Di Cesare Mannelli L, Pacini A. Oxaliplatin-induced blood brain barrier loosening: a new point of view on chemotherapy-induced neurotoxicity. Oncotarget 2018; 9:23426-23438. [PMID: 29805744 PMCID: PMC5955120 DOI: 10.18632/oncotarget.25193] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 04/02/2018] [Indexed: 12/23/2022] Open
Abstract
Oxaliplatin is a key drug in the treatment of advanced metastatic colorectal cancer. Despite its beneficial effects in tumor reduction, the most prevalent side-effect of oxaliplatin treatment is a chemotherapy-induced neuropathy that frequently forces to discontinue the therapy. Indeed, along with direct damage to peripheral nerves, the chemotherapy-related neurotoxicity involves also the central nervous system (CNS) as demonstrated by pain chronicity and cognitive impairment (also known as chemobrain), a newly described pharmacological side effect. The presence of the blood brain barrier (BBB) is instrumental in preventing the entry of the drug into the CNS; here we tested the hypothesis that oxaliplatin might enter the endothelial cells of the BBB vessels and trigger a signaling pathway that induce the disassembly of the tight junctions, the critical components of the BBB integrity. By using a rat brain endothelial cell line (RBE4) we investigated the signaling pathway that ensued the entry of oxaliplatin within the cell. We found that the administration of 10 μM oxaliplatin for 8 and 16 h induced alterations of the tight junction (TJs) proteins zonula occludens-1 (ZO-1) and of F-actin, thus highlighting BBB alteration. Furthermore, we reported that intracellular oxaliplatin rapidly induced increased levels of reactive oxygen species and endoplasmic reticulum stress, assessed by the evaluation of glucose-regulated protein GRP78 expression levels. These events were accompanied by activation of caspase-3 that led to extracellular ATP release. These findings suggested a possible novel mechanism of action for oxaliplatin toxicity that could explain, at least in part, the chemotherapy-related central effects.
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Affiliation(s)
- Jacopo Junio Valerio Branca
- Department of Experimental and Clinical Medicine, Anatomy and Histology Section, University of Florence, Florence, Italy
| | - Mario Maresca
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Pharmacology and Toxicology Section, University of Florence, Florence, Italy
| | - Gabriele Morucci
- Department of Experimental and Clinical Medicine, Anatomy and Histology Section, University of Florence, Florence, Italy
| | - Matteo Becatti
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio", University of Florence, Florence, Italy
| | - Ferdinando Paternostro
- Department of Experimental and Clinical Medicine, Anatomy and Histology Section, University of Florence, Florence, Italy
| | - Massimo Gulisano
- Department of Experimental and Clinical Medicine, Anatomy and Histology Section, University of Florence, Florence, Italy
| | - Carla Ghelardini
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Pharmacology and Toxicology Section, University of Florence, Florence, Italy
| | - Daniela Salvemini
- Department of Pharmacology and Physiology Saint Louis University, Saint Louis, Missouri, United States
| | - Lorenzo Di Cesare Mannelli
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Pharmacology and Toxicology Section, University of Florence, Florence, Italy
| | - Alessandra Pacini
- Department of Experimental and Clinical Medicine, Anatomy and Histology Section, University of Florence, Florence, Italy
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14
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Innovative in cellulo method as an alternative to in vivo neurovirulence test for the characterization and quality control of human live Yellow Fever virus vaccines: A pilot study. Biologicals 2018; 53:19-29. [PMID: 29580693 DOI: 10.1016/j.biologicals.2018.03.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 03/09/2018] [Accepted: 03/16/2018] [Indexed: 01/11/2023] Open
Abstract
Live attenuated vaccines have proved to be mostly valuable in the prevention of infectious diseases in humans, especially in developing countries. The safety and potency of vaccine, and the consistency of vaccine batch-to-batch manufacturing, must be proven before being administrated to humans. For now, the tests used to control vaccine safety largely involve animal testing. For live viral vaccines, regulations require suppliers to demonstrate the absence of neurovirulence in animals, principally in non-human primates and mice. In a search to reduce the use of animals and embracing the 3Rs principles (Replacement, Reduction, Refinement in the use of laboratory animals), we developed a new Blood-Brain Barrier Minibrain (BBB-Minibrain) in cellulo device to evaluate the neuroinvasiveness/neurovirulence of live Yellow Fever virus (YFV) vaccines. A pilot study was performed using the features of two distinct YFV strains, with the ultimate goal of proposing a companion test to characterize YFV neurovirulence. Here, we demonstrate that the BBB-Minibrain model is a promising alternative to consider for future replacement of YFV vaccine in vivo neurovirulence testing (see graphical abstract).
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15
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Guerra G, Lucariello A, Perna A, Botta L, De Luca A, Moccia F. The Role of Endothelial Ca 2+ Signaling in Neurovascular Coupling: A View from the Lumen. Int J Mol Sci 2018; 19:E938. [PMID: 29561829 PMCID: PMC5979341 DOI: 10.3390/ijms19040938] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 03/16/2018] [Accepted: 03/17/2018] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Neurovascular coupling (NVC) is the mechanism whereby an increase in neuronal activity (NA) leads to local elevation in cerebral blood flow (CBF) to match the metabolic requirements of firing neurons. Following synaptic activity, an increase in neuronal and/or astrocyte Ca2+ concentration leads to the synthesis of multiple vasoactive messengers. Curiously, the role of endothelial Ca2+ signaling in NVC has been rather neglected, although endothelial cells are known to control the vascular tone in a Ca2+-dependent manner throughout peripheral vasculature. METHODS We analyzed the literature in search of the most recent updates on the potential role of endothelial Ca2+ signaling in NVC. RESULTS We found that several neurotransmitters (i.e., glutamate and acetylcholine) and neuromodulators (e.g., ATP) can induce dilation of cerebral vessels by inducing an increase in endothelial Ca2+ concentration. This, in turn, results in nitric oxide or prostaglandin E2 release or activate intermediate and small-conductance Ca2+-activated K⁺ channels, which are responsible for endothelial-dependent hyperpolarization (EDH). In addition, brain endothelial cells express multiple transient receptor potential (TRP) channels (i.e., TRPC3, TRPV3, TRPV4, TRPA1), which induce vasodilation by activating EDH. CONCLUSIONS It is possible to conclude that endothelial Ca2+ signaling is an emerging pathway in the control of NVC.
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Affiliation(s)
- Germano Guerra
- Department of Medicine and Health Sciences "Vincenzo Tiberio", University of Molise, via F. De Santis, 86100 Campobasso, Italy.
| | - Angela Lucariello
- Department of Mental Health and Preventive Medicine, Section of Human Anatomy, University of Campania "L. Vanvitelli", 81100 Naples, Italy.
| | - Angelica Perna
- Department of Medicine and Health Sciences "Vincenzo Tiberio", University of Molise, via F. De Santis, 86100 Campobasso, Italy.
| | - Laura Botta
- Laboratory of General Physiology, Department of Biology and Biotechnology "L. Spallanzani", University of Pavia, via Forlanini 6, 27100 Pavia, Italy.
| | - Antonio De Luca
- Department of Mental Health and Preventive Medicine, Section of Human Anatomy, University of Campania "L. Vanvitelli", 81100 Naples, Italy.
| | - Francesco Moccia
- Laboratory of General Physiology, Department of Biology and Biotechnology "L. Spallanzani", University of Pavia, via Forlanini 6, 27100 Pavia, Italy.
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16
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Willebrords J, Maes M, Crespo Yanguas S, Vinken M. Inhibitors of connexin and pannexin channels as potential therapeutics. Pharmacol Ther 2017; 180:144-160. [PMID: 28720428 PMCID: PMC5802387 DOI: 10.1016/j.pharmthera.2017.07.001] [Citation(s) in RCA: 106] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
While gap junctions support the exchange of a number of molecules between neighboring cells, connexin hemichannels provide communication between the cytosol and the extracellular environment of an individual cell. The latter equally holds true for channels composed of pannexin proteins, which display an architecture reminiscent of connexin hemichannels. In physiological conditions, gap junctions are usually open, while connexin hemichannels and, to a lesser extent, pannexin channels are typically closed, yet they can be activated by a number of pathological triggers. Several agents are available to inhibit channels built up by connexin and pannexin proteins, including alcoholic substances, glycyrrhetinic acid, anesthetics and fatty acids. These compounds not always strictly distinguish between gap junctions, connexin hemichannels and pannexin channels, and may have effects on other targets as well. An exception lies with mimetic peptides, which reproduce specific amino acid sequences in connexin or pannexin primary protein structure. In this paper, a state-of-the-art overview is provided on inhibitors of cellular channels consisting of connexins and pannexins with specific focus on their mode-of-action and therapeutic potential.
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Affiliation(s)
- Joost Willebrords
- Department of In Vitro Toxicology and Dermato-cosmetology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, Belgium
| | - Michaël Maes
- Department of In Vitro Toxicology and Dermato-cosmetology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, Belgium
| | - Sara Crespo Yanguas
- Department of In Vitro Toxicology and Dermato-cosmetology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, Belgium
| | - Mathieu Vinken
- Department of In Vitro Toxicology and Dermato-cosmetology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, Belgium.
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17
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Abstract
Neuronal survival, electrical signaling and synaptic activity require a well-balanced micro-environment in the central nervous system. This is achieved by the blood-brain barrier (BBB), an endothelial barrier situated in the brain capillaries, that controls near-to-all passage in and out of the brain. The endothelial barrier function is highly dependent on signaling interactions with surrounding glial, neuronal and vascular cells, together forming the neuro-glio-vascular unit. Within this functional unit, connexin (Cx) channels are of utmost importance for intercellular communication between the different cellular compartments. Connexins are best known as the building blocks of gap junction (GJ) channels that enable direct cell-cell transfer of metabolic, biochemical and electric signals. In addition, beyond their role in direct intercellular communication, Cxs also form unapposed, non-junctional hemichannels in the plasma membrane that allow the passage of several paracrine messengers, complementing direct GJ communication. Within the NGVU, Cxs are expressed in vascular endothelial cells, including those that form the BBB, and are eminent in astrocytes, especially at their endfoot processes that wrap around cerebral vessels. However, despite the density of Cx channels at this so-called gliovascular interface, it remains unclear as to how Cx-based signaling between astrocytes and BBB endothelial cells may converge control over BBB permeability in health and disease. In this review we describe available evidence that supports a role for astroglial as well as endothelial Cxs in the regulation of BBB permeability during development as well as in disease states.
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18
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Zuccolo E, Lim D, Kheder DA, Perna A, Catarsi P, Botta L, Rosti V, Riboni L, Sancini G, Tanzi F, D'Angelo E, Guerra G, Moccia F. Acetylcholine induces intracellular Ca 2+ oscillations and nitric oxide release in mouse brain endothelial cells. Cell Calcium 2017; 66:33-47. [PMID: 28807148 DOI: 10.1016/j.ceca.2017.06.003] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Revised: 06/05/2017] [Accepted: 06/10/2017] [Indexed: 01/29/2023]
Abstract
Basal forebrain neurons increase cortical blood flow by releasing acetylcholine (Ach), which stimulates endothelial cells (ECs) to produce the vasodilating gasotransmitter, nitric oxide (NO). Surprisingly, the mechanism whereby Ach induces NO synthesis in brain microvascular ECs is unknown. An increase in intracellular Ca2+ concentration recruits a multitude of endothelial Ca2+-dependent pathways, such as Ca2+/calmodulin endothelial NO synthase (eNOS). The present investigation sought to investigate the role of intracellular Ca2+ signaling in Ach-induced NO production in bEND5 cells, an established model of mouse brain microvascular ECs, by conventional imaging of cells loaded with the Ca2+-sensitive dye, Fura-2/AM, and the NO-sensitive fluorophore, DAF-DM diacetate. Ach induced dose-dependent Ca2+ oscillations in bEND5 cells, 300 μM being the most effective dose to generate a prolonged Ca2+ burst. Pharmacological manipulation revealed that Ach-evoked Ca2+ oscillations required metabotropic muscarinic receptor (mAchR) activation and were patterned by a complex interplay between repetitive ER Ca2+ release via inositol-1,4,5-trisphosphate receptors (InsP3Rs) and store-operated Ca2+ entry (SOCE). A comprehensive real time-polymerase chain reaction analysis demonstrated the expression of the transcripts encoding for M3-mAChRs, InsP3R1 and InsP3R3, Stim1-2 and Orai2. Next, we found that Ach-induced NO production was hindered by L-NAME, a selective NOS inhibitor, and BAPTA, a membrane permeable intracellular Ca2+ buffer. Moreover, Ach-elicited NO synthesis was blocked by the pharmacological abrogation of the accompanying Ca2+ spikes. Overall, these data shed novel light on the molecular mechanisms whereby neuronally-released Ach controls neurovascular coupling in blood microvessels.
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Affiliation(s)
- Estella Zuccolo
- Laboratory of General Physiology, Department of Biology and Biotechnology "Lazzaro Spallanzani", University of Pavia, Pavia, Italy
| | - Dmitry Lim
- Department of Pharmaceutical Sciences, University of Eastern Piedment "Amedeo Avogadro", Novara, Italy
| | - Dlzar Ali Kheder
- Laboratory of General Physiology, Department of Biology and Biotechnology "Lazzaro Spallanzani", University of Pavia, Pavia, Italy; Department of Biology, University of Zakho, Kurdistan-Region of Iraq, Iraq
| | - Angelica Perna
- Department of Medicine and Health Sciences "Vincenzo Tiberio", University of Molise, Via F. De Santis, 86100 Campobasso, Italy
| | - Paolo Catarsi
- Center for the Study of Myelofibrosis, Research Laboratory of Biotechnology, Foundation IRCCS Policlinico San Matteo, Pavia, Italy
| | - Laura Botta
- Laboratory of General Physiology, Department of Biology and Biotechnology "Lazzaro Spallanzani", University of Pavia, Pavia, Italy
| | - Vittorio Rosti
- Center for the Study of Myelofibrosis, Research Laboratory of Biotechnology, Foundation IRCCS Policlinico San Matteo, Pavia, Italy
| | - Laura Riboni
- Department of Medical Biotechnology and Translational Medicine, LITA-Segrate, University of Milan, Segrate, 20090 Milan, Italy
| | - Giulio Sancini
- Department of Experimental Medicine, University of Milano-Bicocca, 20900 Monza, Italy
| | - Franco Tanzi
- Laboratory of General Physiology, Department of Biology and Biotechnology "Lazzaro Spallanzani", University of Pavia, Pavia, Italy
| | - Egidio D'Angelo
- Department of Brain and Behavioral Sciences, University of Pavia, 27100 Pavia, Italy; Brain Connectivity Center, C. Mondino National Neurological Institute, 27100 Pavia, Italy
| | - Germano Guerra
- Department of Medicine and Health Sciences "Vincenzo Tiberio", University of Molise, Via F. De Santis, 86100 Campobasso, Italy.
| | - Francesco Moccia
- Laboratory of General Physiology, Department of Biology and Biotechnology "Lazzaro Spallanzani", University of Pavia, Pavia, Italy.
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19
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Luo B, Zhao L, Zhang X, Kan B, Liu Y, Jia Y, Han J, Yu J. Acupuncture upregulates G protein coupled activity in SAMP8 mice. Acupunct Med 2017; 35:289-296. [PMID: 28450287 DOI: 10.1136/acupmed-2016-011139] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/30/2016] [Indexed: 11/04/2022]
Abstract
BACKGROUND Transmembrane and intracellular signal transduction of G protein is closely related to the pathophysiology of Alzheimer's disease (AD). OBJECTIVE To explore the effects of Sanjiao acupuncture on G protein signal transduction pathways in the pathogenesis of AD. METHODS 36 senescence-accelerated (SAM) prone 8 mice were divided into three groups that remained untreated (SAMP8, n=12) or received Sanjiao acupuncture (SAMP8+SA, n=12) or control acupuncture (SAMP8+CA, n=12). An additional control group of SAM resistant 1 mice was included (SAMR1 group, n=12). Morris water maze tests were used to investigate learning and memory abilities. Immunoprecipitation and Western blotting were used to study expression of G protein subunits and their activities in the cortex/hippocampus. RESULTS Behavioural analysis showed that acupuncture attenuated the severe cognitive deficits observed in untreated/CA-treated SAMP8 mice. The findings of the G protein activation assays via immunoprecipitation and Western blots were that the physiologically coupled activation rate (PCAR) and maximal coupled activation rate (MCAR) of Gαs and Gαi were decreased in the cortex of SAMP8 vs SAMR1 mice. Sanjiao acupuncture induced an upregulation in the PCAR of Gαs and Gαi. In the hippocampus of untreated SAMP8 mice, the PCAR of Gαs and MCAR of both Gαs and Gαi declined, and Sanjiao acupuncture was associated with an upregulation in the MCAR of Gαs and Gαi. There were no significant differences in Gαs and Gαi expression between the groups. CONCLUSIONS Sanjiao acupuncture attenuates cognitive deficits in a mouse model of AD via upregulation of G protein activity and stabilisation of the cellular signal.
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Affiliation(s)
- Benhua Luo
- First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin, China.,Guangxi University of Traditional Chinese Medicine, Nanning, China.,Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Lan Zhao
- First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin, China.,Tianjin Key Laboratory of Acupuncture and Moxibustion, Tianjin, China
| | - Xuezhu Zhang
- First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin, China.,Tianjin Key Laboratory of Acupuncture and Moxibustion, Tianjin, China
| | - Bohong Kan
- First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin, China.,Tianjin Key Laboratory of Acupuncture and Moxibustion, Tianjin, China
| | - Yunhe Liu
- First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Yujie Jia
- First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin, China.,Tianjin Key Laboratory of Acupuncture and Moxibustion, Tianjin, China
| | - Jingxian Han
- First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Jianchun Yu
- First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin, China
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20
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Qudrat A, Truong K. Engineering Synthetic Proteins to Generate Ca 2+ Signals in Mammalian Cells. ACS Synth Biol 2017; 6:582-590. [PMID: 28301940 DOI: 10.1021/acssynbio.6b00310] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The versatility of Ca2+ signals allows it to regulate diverse cellular processes such as migration, apoptosis, motility and exocytosis. In some receptors (e.g., VEGFR2), Ca2+ signals are generated upon binding their ligand(s) (e.g., VEGF-A). Here, we employed a design strategy to engineer proteins that generate a Ca2+ signal upon binding various extracellular stimuli by creating fusions of protein domains that oligomerize to the transmembrane domain and the cytoplasmic tail of the VEGFR2. To test the strategy, we created chimeric proteins that generate Ca2+ signals upon stimulation with various extracellular stimuli (e.g., rapamycin, EDTA or extracellular free Ca2+). By coupling these chimeric proteins that generate Ca2+ signals with proteins that respond to Ca2+ signals, we rewired, for example, dynamic cellular blebbing to increases in extracellular free Ca2+. Thus, using this design strategy, it is possible to engineer proteins to generate a Ca2+ signal to rewire a wide range of extracellular stimuli to a wide range of Ca2+-activated processes.
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Affiliation(s)
- Anam Qudrat
- Institute of Biomaterials
and Biomedical Engineering, University of Toronto, 164 College
Street, Toronto, Ontario M5S 3G9, Canada
| | - Kevin Truong
- Institute of Biomaterials
and Biomedical Engineering, University of Toronto, 164 College
Street, Toronto, Ontario M5S 3G9, Canada
- Edward
S. Rogers, Sr. Department of Electrical and Computer Engineering, University of Toronto, 10 King’s College Circle, Toronto, Ontario M5S 3G4, Canada
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21
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Bader A, Bintig W, Begandt D, Klett A, Siller IG, Gregor C, Schaarschmidt F, Weksler B, Romero I, Couraud PO, Hell SW, Ngezahayo A. Adenosine receptors regulate gap junction coupling of the human cerebral microvascular endothelial cells hCMEC/D3 by Ca 2+ influx through cyclic nucleotide-gated channels. J Physiol 2017; 595:2497-2517. [PMID: 28075020 DOI: 10.1113/jp273150] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Accepted: 12/16/2016] [Indexed: 12/25/2022] Open
Abstract
KEY POINTS Gap junction channels are essential for the formation and regulation of physiological units in tissues by allowing the lateral cell-to-cell diffusion of ions, metabolites and second messengers. Stimulation of the adenosine receptor subtype A2B increases the gap junction coupling in the human blood-brain barrier endothelial cell line hCMEC/D3. Although the increased gap junction coupling is cAMP-dependent, neither the protein kinase A nor the exchange protein directly activated by cAMP were involved in this increase. We found that cAMP activates cyclic nucleotide-gated (CNG) channels and thereby induces a Ca2+ influx, which leads to the increase in gap junction coupling. The report identifies CNG channels as a possible physiological link between adenosine receptors and the regulation of gap junction channels in endothelial cells of the blood-brain barrier. ABSTRACT The human cerebral microvascular endothelial cell line hCMEC/D3 was used to characterize the physiological link between adenosine receptors and the gap junction coupling in endothelial cells of the blood-brain barrier. Expressed adenosine receptor subtypes and connexin (Cx) isoforms were identified by RT-PCR. Scrape loading/dye transfer was used to evaluate the impact of the A2A and A2B adenosine receptor subtype agonist 2-phenylaminoadenosine (2-PAA) on the gap junction coupling. We found that 2-PAA stimulated cAMP synthesis and enhanced gap junction coupling in a concentration-dependent manner. This enhancement was accompanied by an increase in gap junction plaques formed by Cx43. Inhibition of protein kinase A did not affect the 2-PAA-related enhancement of gap junction coupling. In contrast, the cyclic nucleotide-gated (CNG) channel inhibitor l-cis-diltiazem, as well as the chelation of intracellular Ca2+ with BAPTA, or the absence of external Ca2+ , suppressed the 2-PAA-related enhancement of gap junction coupling. Moreover, we observed a 2-PAA-dependent activation of CNG channels by a combination of electrophysiology and pharmacology. In conclusion, the stimulation of adenosine receptors in hCMEC/D3 cells induces a Ca2+ influx by opening CNG channels in a cAMP-dependent manner. Ca2+ in turn induces the formation of new gap junction plaques and a consecutive sustained enhancement of gap junction coupling. The report identifies CNG channels as a physiological link that integrates gap junction coupling into the adenosine receptor-dependent signalling of endothelial cells of the blood-brain barrier.
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Affiliation(s)
- Almke Bader
- Institute of Biophysics, Leibniz University Hannover, Hannover, Germany
| | - Willem Bintig
- Institute of Biochemistry, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Daniela Begandt
- Walter Brendel Centre of Experimental Medicine, Department of Cardiovascular Physiology and Pathophysiology, Biomedical Center, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany
| | - Anne Klett
- Institute of Biophysics, Leibniz University Hannover, Hannover, Germany
| | - Ina G Siller
- Institute of Biophysics, Leibniz University Hannover, Hannover, Germany
| | - Carola Gregor
- Department of NanoBiophotonics, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | | | - Babette Weksler
- Weill Medical College of Cornell University, New York, NY, USA
| | - Ignacio Romero
- Department of Biological Sciences, The Open University, Walton Hall, Milton Keynes, UK
| | - Pierre-Olivier Couraud
- INSERM, U1016, Institut Cochin, Paris, France.,CNRS, UMR8104, Paris, France.,Université Paris Descartes, Paris, France
| | - Stefan W Hell
- Department of NanoBiophotonics, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Anaclet Ngezahayo
- Institute of Biophysics, Leibniz University Hannover, Hannover, Germany.,Center for Systems Neuroscience Hannover, University of Veterinary Medicine Hannover Foundation, Hannover, Germany
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22
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Duan CY, Zhang J, Wu HL, Li T, Liu LM. Regulatory mechanisms, prophylaxis and treatment of vascular leakage following severe trauma and shock. Mil Med Res 2017; 4:11. [PMID: 28361006 PMCID: PMC5370457 DOI: 10.1186/s40779-017-0117-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 03/06/2017] [Indexed: 02/08/2023] Open
Abstract
Vascular leakage, or increased vascular permeability, is a common but important pathological process for various critical diseases, including severe trauma, shock, sepsis, and multiple organ dysfunction syndrome (MODS), and has become one of the most important causes of death for intensive care units (ICU) patients. Currently, although there has been some progress in knowledge of the pathogenesis of these vascular disorders, the detailed mechanisms remain unclear, and effective prophylaxis and treatment are still lacking. In this study, we aimed to provide a review of the literature regarding the regulatory mechanisms and prophylaxis as well as the treatment of vascular leakage in critical diseases such as severe trauma and shock, which could be beneficial for the overall clinical treatment of vascular leakage disorders.
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Affiliation(s)
- Chen-Yang Duan
- State Key Laboratory of Trauma, Burns and Combined Injury, Second Department of Research Institute of Surgery, Daping Hospital, Third Military Medical University, Chongqing, 400042 China
| | - Jie Zhang
- State Key Laboratory of Trauma, Burns and Combined Injury, Second Department of Research Institute of Surgery, Daping Hospital, Third Military Medical University, Chongqing, 400042 China
| | - Hui-Ling Wu
- State Key Laboratory of Trauma, Burns and Combined Injury, Second Department of Research Institute of Surgery, Daping Hospital, Third Military Medical University, Chongqing, 400042 China
| | - Tao Li
- State Key Laboratory of Trauma, Burns and Combined Injury, Second Department of Research Institute of Surgery, Daping Hospital, Third Military Medical University, Chongqing, 400042 China
| | - Liang-Ming Liu
- State Key Laboratory of Trauma, Burns and Combined Injury, Second Department of Research Institute of Surgery, Daping Hospital, Third Military Medical University, Chongqing, 400042 China
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23
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Kaisar MA, Sajja RK, Prasad S, Abhyankar VV, Liles T, Cucullo L. New experimental models of the blood-brain barrier for CNS drug discovery. Expert Opin Drug Discov 2016; 12:89-103. [PMID: 27782770 DOI: 10.1080/17460441.2017.1253676] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
INTRODUCTION The blood-brain barrier (BBB) is a dynamic biological interface which actively controls the passage of substances between the blood and the central nervous system (CNS). From a biological and functional standpoint, the BBB plays a crucial role in maintaining brain homeostasis inasmuch that deterioration of BBB functions are prodromal to many CNS disorders. Conversely, the BBB hinders the delivery of drugs targeting the brain to treat a variety of neurological diseases. Area covered: This article reviews recent technological improvements and innovation in the field of BBB modeling including static and dynamic cell-based platforms, microfluidic systems and the use of stem cells and 3D printing technologies. Additionally, the authors laid out a roadmap for the integration of microfluidics and stem cell biology as a holistic approach for the development of novel in vitro BBB platforms. Expert opinion: Development of effective CNS drugs has been hindered by the lack of reliable strategies to mimic the BBB and cerebrovascular impairments in vitro. Technological advancements in BBB modeling have fostered the development of highly integrative and quasi- physiological in vitro platforms to support the process of drug discovery. These advanced in vitro tools are likely to further current understanding of the cerebrovascular modulatory mechanisms.
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Affiliation(s)
- Mohammad A Kaisar
- a Department of Pharmaceutical Sciences , Texas Tech University Health Sciences Center , Amarillo , TX , USA
| | - Ravi K Sajja
- a Department of Pharmaceutical Sciences , Texas Tech University Health Sciences Center , Amarillo , TX , USA
| | - Shikha Prasad
- a Department of Pharmaceutical Sciences , Texas Tech University Health Sciences Center , Amarillo , TX , USA
| | - Vinay V Abhyankar
- c Biological Microsystems Division at The University of Texas at Arlington Research Institute , Fort Worth , TX , USA
| | - Taylor Liles
- a Department of Pharmaceutical Sciences , Texas Tech University Health Sciences Center , Amarillo , TX , USA
| | - Luca Cucullo
- a Department of Pharmaceutical Sciences , Texas Tech University Health Sciences Center , Amarillo , TX , USA.,b Center for Blood Brain Barrier Research , Texas Tech University Health Sciences Center , Amarillo , TX , USA
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24
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B7-H1 shapes T-cell-mediated brain endothelial cell dysfunction and regional encephalitogenicity in spontaneous CNS autoimmunity. Proc Natl Acad Sci U S A 2016; 113:E6182-E6191. [PMID: 27671636 DOI: 10.1073/pnas.1601350113] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Molecular mechanisms that determine lesion localization or phenotype variation in multiple sclerosis are mostly unidentified. Although transmigration of activated encephalitogenic T cells across the blood-brain barrier (BBB) is a crucial step in the disease pathogenesis of CNS autoimmunity, the consequences on brain endothelial barrier integrity upon interaction with such T cells and subsequent lesion formation and distribution are largely unknown. We made use of a transgenic spontaneous mouse model of CNS autoimmunity characterized by inflammatory demyelinating lesions confined to optic nerves and spinal cord (OSE mice). Genetic ablation of a single immune-regulatory molecule in this model [i.e., B7-homolog 1 (B7-H1, PD-L1)] not only significantly increased incidence of spontaneous CNS autoimmunity and aggravated disease course, especially in the later stages of disease, but also importantly resulted in encephalitogenic T-cell infiltration and lesion formation in normally unaffected brain regions, such as the cerebrum and cerebellum. Interestingly, B7-H1 ablation on myelin oligodendrocyte glycoprotein-specific CD4+ T cells, but not on antigen-presenting cells, amplified T-cell effector functions, such as IFN-γ and granzyme B production. Therefore, these T cells were rendered more capable of eliciting cell contact-dependent brain endothelial cell dysfunction and increased barrier permeability in an in vitro model of the BBB. Our findings suggest that a single immune-regulatory molecule on T cells can be ultimately responsible for localized BBB breakdown, and thus substantial changes in lesion topography in the context of CNS autoimmunity.
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25
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Dobrynina LA, Kalashnikova LA, Bakulin IS, Kremneva EI, Krotenkova MV, Shamtieva KV. [Posterior reversible encephalopathy syndrome due to hypocalcemia: a description of a case and an analysis of a pathogenic role of electrolyte disturbances]. Zh Nevrol Psikhiatr Im S S Korsakova 2016; 116:70-77. [PMID: 27500881 DOI: 10.17116/jnevro20161167170-77] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Afemale patient with recurrent posterior reversible encephalopathy syndrome, severe hypocalcemia due to extirpation of the parathyroid glands is described. The disease was characterized by the acute development of headache, seizures, cognitive and behavioral disorders, mental confusion, transitory blood pressure increasing. The vasogenic edema in the posterior parts of the brain, detected by CT at the first exacerbation,was completely regressed. The residual neurological deficit and MRI changes remained after the recurrent exacerbations. Main clinical features of PRESare explained by hypocalcemia and accompanying electrolyte disturbances.The reported case shows the necessity to study blood electrolytes in patients with PRES to clarify their pathogenic role and the necessity of drug correction.
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26
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Soon ASC, Chua JW, Becker DL. Connexins in endothelial barrier function - novel therapeutic targets countering vascular hyperpermeability. Thromb Haemost 2016; 116:852-867. [PMID: 27488046 DOI: 10.1160/th16-03-0210] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Accepted: 07/15/2016] [Indexed: 12/14/2022]
Abstract
Prolonged vascular hyperpermeability is a common feature of many diseases. Vascular hyperpermeability is typically associated with changes in the expression patterns of adherens and tight junction proteins. Here, we focus on the less-appreciated contribution of gap junction proteins (connexins) to basal vascular permeability and endothelial dysfunction. First, we assess the association of connexins with endothelial barrier integrity by introducing tools used in connexin biology and relating the findings to customary readouts in vascular biology. Second, we explore potential mechanistic ties between connexins and junction regulation. Third, we review the role of connexins in microvascular organisation and development, focusing on interactions of the endothelium with mural cells and tissue-specific perivascular cells. Last, we see how connexins contribute to the interactions between the endothelium and components of the immune system, by using neutrophils as an example. Mounting evidence of crosstalk between connexins and other junction proteins suggests that we rethink the way in which different junction components contribute to endothelial barrier function. Given the multiple points of connexin-mediated communication arising from the endothelium, there is great potential for synergism between connexin-targeted inhibitors and existing immune-targeted therapeutics. As more drugs targeting connexins progress through clinical trials, it is hoped that some might prove effective at countering vascular hyperpermeability.
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Affiliation(s)
| | | | - David Laurence Becker
- David L. Becker, PhD, Lee Kong Chian School of Medicine, Nanyang Technological University, 11 Mandalay Road, 308232 Singapore, Tel: +65 6592 3961, Fax: +65 6515 0417, E-mail:
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27
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Immortalized endothelial cell lines for in vitro blood–brain barrier models: A systematic review. Brain Res 2016; 1642:532-545. [DOI: 10.1016/j.brainres.2016.04.024] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 04/05/2016] [Accepted: 04/12/2016] [Indexed: 12/18/2022]
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28
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Esseltine JL, Laird DW. Next-Generation Connexin and Pannexin Cell Biology. Trends Cell Biol 2016; 26:944-955. [PMID: 27339936 DOI: 10.1016/j.tcb.2016.06.003] [Citation(s) in RCA: 93] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Revised: 06/02/2016] [Accepted: 06/06/2016] [Indexed: 01/17/2023]
Abstract
Connexins and pannexins are two families of large-pore channel forming proteins that are capable of passing small signaling molecules. While connexins serve the seminal task of direct gap junctional intercellular communication, pannexins are far less understood but function primarily as single membrane channels in autocrine and paracrine signaling. Advancements in connexin and pannexin biology in recent years has revealed that in addition to well-described classical functions at the plasma membrane, exciting new evidence suggests that connexins and pannexins participate in alternative pathways involving multiple intracellular compartments. Here we briefly highlight classical functions of connexins and pannexins but focus our attention mostly on the transformative findings that suggest that these channel-forming proteins may serve roles far beyond our current understandings.
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Affiliation(s)
- Jessica L Esseltine
- Department of Anatomy and Cell Biology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, ON, Canada
| | - Dale W Laird
- Department of Anatomy and Cell Biology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, ON, Canada.
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29
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De Bock M, Van Haver V, Vandenbroucke RE, Decrock E, Wang N, Leybaert L. Into rather unexplored terrain-transcellular transport across the blood-brain barrier. Glia 2016; 64:1097-123. [DOI: 10.1002/glia.22960] [Citation(s) in RCA: 92] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Revised: 11/16/2015] [Accepted: 12/03/2015] [Indexed: 01/22/2023]
Affiliation(s)
- Marijke De Bock
- Physiology Group, Department of Basic Medical Sciences; Ghent University; Ghent Belgium
| | - Valérie Van Haver
- Physiology Group, Department of Basic Medical Sciences; Ghent University; Ghent Belgium
| | - Roosmarijn E. Vandenbroucke
- Inflammation Research Center, VIB; Ghent Belgium
- Department of Biomedical Molecular Biology; Ghent University; Ghent Belgium
| | - Elke Decrock
- Physiology Group, Department of Basic Medical Sciences; Ghent University; Ghent Belgium
| | - Nan Wang
- Physiology Group, Department of Basic Medical Sciences; Ghent University; Ghent Belgium
| | - Luc Leybaert
- Physiology Group, Department of Basic Medical Sciences; Ghent University; Ghent Belgium
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30
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Rakkar K, Bayraktutan U. Increases in intracellular calcium perturb blood–brain barrier via protein kinase C-alpha and apoptosis. Biochim Biophys Acta Mol Basis Dis 2016; 1862:56-71. [DOI: 10.1016/j.bbadis.2015.10.016] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Revised: 10/14/2015] [Accepted: 10/20/2015] [Indexed: 12/11/2022]
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31
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Liu X, Gangoso E, Yi C, Jeanson T, Kandelman S, Mantz J, Giaume C. General anesthetics have differential inhibitory effects on gap junction channels and hemichannels in astrocytes and neurons. Glia 2015; 64:524-36. [PMID: 26666873 DOI: 10.1002/glia.22946] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Accepted: 11/16/2015] [Indexed: 11/07/2022]
Abstract
Astrocytes represent a major non-neuronal cell population actively involved in brain functions and pathologies. They express a large amount of gap junction proteins that allow communication between adjacent glial cells and the formation of glial networks. In addition, these membrane proteins can also operate as hemichannels, through which "gliotransmitters" are released, and thus contribute to neuroglial interaction. There are now reports demonstrating that alterations of astroglial gap junction communication and/or hemichannel activity impact neuronal and synaptic activity. Two decades ago we reported that several general anesthetics inhibited gap junctions in primary cultures of astrocytes (Mantz et al., (1993) Anesthesiology 78(5):892-901). As there are increasing studies investigating neuroglial interactions in anesthetized mice, we here updated this previous study by employing acute cortical slices and by characterizing the effects of general anesthetics on both astroglial gap junctions and hemichannels. As hemichannel activity is not detected in cortical astrocytes under basal conditions, we treated acute slices with the endotoxin LPS or proinflammatory cytokines to induce hemichannel activity in astrocytes, which in turn activated neuronal hemichannels. We studied two extensively used anesthetics, propofol and ketamine, and the more recently developed dexmedetomidine. We report that these drugs have differential inhibitory effects on gap junctional communication and hemichannel activity in astrocytes when used in their respective, clinically relevant concentrations, and that dexmedetomidine appears to be the least effective on both channel functions. In addition, the three anesthetics have similar effects on neuronal hemichannels. Altogether, our observations may contribute to optimizing the selection of anesthetics for in vivo animal studies.
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Affiliation(s)
- Xinhe Liu
- Collège De France, Center for Interdisciplinary Research in Biology (CIRB)/Centre National De La Recherche Scientifique, Unité Mixte De Recherche 7241/Institut National De La Santé Et De La Recherche Médicale U1050, Paris Cedex 05, France.,University Pierre Et Marie Curie, Paris, France.,MEMOLIFE Laboratory of Excellence and Paris Science Lettre Research University, Paris, France
| | - Ester Gangoso
- Collège De France, Center for Interdisciplinary Research in Biology (CIRB)/Centre National De La Recherche Scientifique, Unité Mixte De Recherche 7241/Institut National De La Santé Et De La Recherche Médicale U1050, Paris Cedex 05, France.,University Pierre Et Marie Curie, Paris, France.,MEMOLIFE Laboratory of Excellence and Paris Science Lettre Research University, Paris, France
| | - Chenju Yi
- Collège De France, Center for Interdisciplinary Research in Biology (CIRB)/Centre National De La Recherche Scientifique, Unité Mixte De Recherche 7241/Institut National De La Santé Et De La Recherche Médicale U1050, Paris Cedex 05, France.,University Pierre Et Marie Curie, Paris, France.,MEMOLIFE Laboratory of Excellence and Paris Science Lettre Research University, Paris, France
| | - Tiffany Jeanson
- Collège De France, Center for Interdisciplinary Research in Biology (CIRB)/Centre National De La Recherche Scientifique, Unité Mixte De Recherche 7241/Institut National De La Santé Et De La Recherche Médicale U1050, Paris Cedex 05, France.,University Pierre Et Marie Curie, Paris, France.,MEMOLIFE Laboratory of Excellence and Paris Science Lettre Research University, Paris, France
| | - Stanislas Kandelman
- Département D'anesthésie Et De Réanimation, HUPNVS, Université Paris Diderot, Paris, France
| | - Jean Mantz
- Service D'anesthésie Réanimation, Hôpital Européen Georges Pompidou, Paris Descartes University, Paris, France.,Unité D'histopathologie Humaine Et Modèles Animaux Département Infection Et Epidémiologie Institut Pasteur 25, Rue Du Docteur Roux, Paris, France
| | - Christian Giaume
- Collège De France, Center for Interdisciplinary Research in Biology (CIRB)/Centre National De La Recherche Scientifique, Unité Mixte De Recherche 7241/Institut National De La Santé Et De La Recherche Médicale U1050, Paris Cedex 05, France.,University Pierre Et Marie Curie, Paris, France.,MEMOLIFE Laboratory of Excellence and Paris Science Lettre Research University, Paris, France
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32
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Soares ES, Mendonça MCP, da Cruz-Höfling MA. eNOS uncoupling in the cerebellum after BBB disruption by exposure to Phoneutria nigriventer spider venom. Toxicon 2015. [PMID: 26206339 DOI: 10.1016/j.toxicon.2015.07.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Numerous studies have shown that the venom of Phoneutria nigriventer (PNV) armed-spider causes excitotoxic signals and blood-brain barrier breakdown (BBBb) in rats. Nitric oxide (NO) is a signaling molecule which has a role in endothelium homeostasis and vascular health. The present study investigated the relevance of endothelial NO synthase (eNOS) uncoupling to clinical neurotoxic evolution induced by PNV. eNOS immunoblotting of cerebellum lysates processed through low-temperature SDS-PAGE revealed significant increased monomerization of the enzyme at critical periods of severe envenoming (1-2 h), whereas eNOS dimerization reversal paralleled to amelioration of animals condition (5-72 h). Moreover, eNOS uncoupling was accompanied by increased expression in calcium-sensing calmodulin protein and calcium-binding calbindin-D28 protein in cerebellar neurons. It is known that greater eNOS monomers than dimers implies the inability of eNOS to produce NO leading to superoxide production and endothelial/vascular barrier dysfunction. We suggest that transient eNOS deactivation and disturbances in calcium handling reduce NO production and enhance production of free radicals thus contributing to endothelial dysfunction in the cerebellum of envenomed rats. In addition, eNOS uncoupling compromises the enzyme capacity to respond to shear stress contributing to perivascular edema and it is one of the mechanisms involved in the BBBb promoted by PNV.
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Affiliation(s)
- Edilene Siqueira Soares
- Department of Biochemistry and Tissue Biology, Institute of Biology, State University of Campinas (UNICAMP), Zip Code 13 083-970, Campinas, SP, Brazil
| | - Monique Culturato Padilha Mendonça
- Department of Biochemistry and Tissue Biology, Institute of Biology, State University of Campinas (UNICAMP), Zip Code 13 083-970, Campinas, SP, Brazil; Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas (UNICAMP), Zip Code 13 083-970, Campinas, SP, Brazil
| | - Maria Alice da Cruz-Höfling
- Department of Biochemistry and Tissue Biology, Institute of Biology, State University of Campinas (UNICAMP), Zip Code 13 083-970, Campinas, SP, Brazil; Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas (UNICAMP), Zip Code 13 083-970, Campinas, SP, Brazil.
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33
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Schirmeier S, Klämbt C. The Drosophila blood-brain barrier as interface between neurons and hemolymph. Mech Dev 2015; 138 Pt 1:50-5. [PMID: 26103549 DOI: 10.1016/j.mod.2015.06.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Revised: 06/01/2015] [Accepted: 06/16/2015] [Indexed: 02/05/2023]
Abstract
The blood-brain barrier is an evolutionary ancient structure that provides direct support and protection of the nervous system. In all systems, it establishes a tight diffusion barrier that hinders uncontrolled paracellular diffusion into the nervous system. In invertebrates, the blood-brain barrier separates the nervous system from the hemolymph. Thus, the barrier-forming cells need to actively import ions and nutrients into the nervous system. In addition, metabolic or environmental signals from the external world have to be transmitted across the barrier into the nervous system. The first blood-brain barrier that formed during evolution was most likely based on glial cells. Invertebrates as well as primitive vertebrates still have a purely glial-based blood-brain barrier. Here we review the development and function of the barrier forming glial cells at the example of Drosophila.
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Affiliation(s)
- Stefanie Schirmeier
- Institut für Neuro- und Verhaltensbiologie, Badestr. 9, 48149 Münster, Germany
| | - Christian Klämbt
- Institut für Neuro- und Verhaltensbiologie, Badestr. 9, 48149 Münster, Germany.
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34
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Marques F, Sousa JC. The choroid plexus is modulated by various peripheral stimuli: implications to diseases of the central nervous system. Front Cell Neurosci 2015; 9:136. [PMID: 26236190 PMCID: PMC4394702 DOI: 10.3389/fncel.2015.00136] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2014] [Accepted: 03/23/2015] [Indexed: 12/30/2022] Open
Abstract
The blood brain barrier (BBB) and the blood cerebrospinal fluid barrier (BCSFB) form the barriers of the brain. These barriers are essential not only for the protection of the brain, but also in regulating the exchange of cells and molecules in and out of the brain. The choroid plexus (CP) epithelial cells and the arachnoid membrane form the BCSFB. The CP is structurally divided into two independent compartments: one formed by a unique and continuous line of epithelial cells that rest upon a basal lamina; and, a second consisting of a central core formed by connective and highly vascularized tissue populated by diverse cell types (fibroblasts, macrophages and dendritic cells). Here, we review how the CP transcriptome and secretome vary depending on the nature and duration of the stimuli to which the CP is exposed. Specifically, when the peripheral stimulation is acute the CP response is rapid, strong and transient, whereas if the stimulation is sustained in time the CP response persists but it is weaker. Furthermore, not all of the epithelium responds at the same time to peripheral stimulation, suggesting the existence of a synchrony system between individual CP epithelial cells.
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Affiliation(s)
- Fernanda Marques
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho Braga, Portugal ; ICVS/3B's - PT Government Associate Laboratory Braga/Guimarães, Portugal
| | - João C Sousa
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho Braga, Portugal ; ICVS/3B's - PT Government Associate Laboratory Braga/Guimarães, Portugal
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35
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Decrock E, De Bock M, Wang N, Bol M, Gadicherla AK, Leybaert L. Electroporation loading and flash photolysis to investigate intra- and intercellular Ca2+ signaling. Cold Spring Harb Protoc 2015; 2015:239-49. [PMID: 25734071 DOI: 10.1101/pdb.top066068] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Many cellular functions are driven by variations in the intracellular Ca(2+) concentration ([Ca(2+)]i), which may appear as a single-event transient [Ca(2+)]i elevation, repetitive [Ca(2+)]i increases known as Ca(2+) oscillations, or [Ca(2+)]i increases propagating in the cytoplasm as Ca(2+) waves. Additionally, [Ca(2+)]i changes can be communicated between cells as intercellular Ca(2+) waves (ICWs). ICWs are mediated by two possible mechanisms acting in parallel: one involving gap junctions that form channels directly linking the cytoplasm of adjacent cells and one involving a paracrine messenger, in most cases ATP, that is released into the extracellular space, leading to [Ca(2+)]i changes in neighboring cells. The intracellular messenger inositol 1,4,5-trisphosphate (IP3) that triggers Ca(2+) release from Ca(2+) stores is crucial in these two ICW propagation scenarios, and is also a potent trigger to initiate ICWs. Loading inactive, "caged" IP3 into cells followed by photolytic "uncaging" with UV light, thereby liberating IP3, is a well-established method to trigger [Ca(2+)]i changes in single cells that is also effective in initiating ICWs. We here describe a method to load cells with caged IP3 by local electroporation of monolayer cell cultures and to apply flash photolysis to increase intracellular IP3 and induce [Ca(2+)]i changes, or initiate ICWs. Moreover, the electroporation method allows loading of membrane-impermeable agents that interfere with IP3 and Ca(2+) signaling.
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Affiliation(s)
- Elke Decrock
- Department of Basic Medical Sciences, Physiology Group, Ghent University, 9000 Ghent, Belgium
| | - Marijke De Bock
- Department of Basic Medical Sciences, Physiology Group, Ghent University, 9000 Ghent, Belgium
| | - Nan Wang
- Department of Basic Medical Sciences, Physiology Group, Ghent University, 9000 Ghent, Belgium
| | - Mélissa Bol
- Department of Basic Medical Sciences, Physiology Group, Ghent University, 9000 Ghent, Belgium
| | - Ashish K Gadicherla
- Department of Basic Medical Sciences, Physiology Group, Ghent University, 9000 Ghent, Belgium
| | - Luc Leybaert
- Department of Basic Medical Sciences, Physiology Group, Ghent University, 9000 Ghent, Belgium
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36
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Kaneko Y, Tachikawa M, Akaogi R, Fujimoto K, Ishibashi M, Uchida Y, Couraud PO, Ohtsuki S, Hosoya KI, Terasaki T. Contribution of pannexin 1 and connexin 43 hemichannels to extracellular calcium-dependent transport dynamics in human blood-brain barrier endothelial cells. J Pharmacol Exp Ther 2015; 353:192-200. [PMID: 25670633 DOI: 10.1124/jpet.114.220210] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Dysregulation of blood-brain barrier (BBB) transport function is thought to exacerbate neuronal damage in acute ischemic stroke. The purpose of this study was to clarify the characteristics of pannexin (Px) and/or connexin (Cx) hemichannel(s)-mediated transport of organic anions and cations in human BBB endothelial cell line hCMEC/D3 and to identify inhibitors of hemichannel opening in hCMEC/D3 cells in the absence of extracellular Ca(2+), a condition mimicking acute ischemic stroke. In the absence of extracellular Ca(2+), the cells showed increased uptake and efflux transport of organic ionic fluorescent dyes. Classic hemichannel inhibitors markedly inhibited the enhanced uptake and efflux. Quantitative targeted absolute proteomics confirmed Px1 and Cx43 protein expression in plasma membrane of hCMEC/D3 cells. Knockdown of Px1 and Cx43 with the small interfering RNAs significantly inhibited the enhanced uptake and efflux of organic anionic and cationic fluorescent dyes. Clinically used cilnidipine and progesterone, which have neuroprotective effects in animal ischemia models, were identified as inhibitors of hemichannel opening. These findings suggest that altered transport dynamics at the human BBB in the absence of extracellular Ca(2+) is at least partly attributable to opening of Px1 and Cx43 hemichannels. Therefore, we speculate that Px1 and Cx43 may be potential drug targets to ameliorate BBB transport dysregulation during acute ischemia.
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Affiliation(s)
- Yosuke Kaneko
- Division of Membrane Transport and Drug Targeting, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan (Y.K., M.T., R.A., Y.U., T.T.); Department of Applied Chemistry and Biochemistry, Faculty of Engineering, Kyushu Sangyo University, Fukuoka, Japan (K.F., M.I.); INSERM, U1016, Institut Cochin and CNRS, UMR8104, and Université Paris Descartes, Paris, France (P.-O.C.); Department of Pharmaceutical Microbiology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan (S.O.); and Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan (K.H.)
| | - Masanori Tachikawa
- Division of Membrane Transport and Drug Targeting, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan (Y.K., M.T., R.A., Y.U., T.T.); Department of Applied Chemistry and Biochemistry, Faculty of Engineering, Kyushu Sangyo University, Fukuoka, Japan (K.F., M.I.); INSERM, U1016, Institut Cochin and CNRS, UMR8104, and Université Paris Descartes, Paris, France (P.-O.C.); Department of Pharmaceutical Microbiology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan (S.O.); and Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan (K.H.)
| | - Ryo Akaogi
- Division of Membrane Transport and Drug Targeting, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan (Y.K., M.T., R.A., Y.U., T.T.); Department of Applied Chemistry and Biochemistry, Faculty of Engineering, Kyushu Sangyo University, Fukuoka, Japan (K.F., M.I.); INSERM, U1016, Institut Cochin and CNRS, UMR8104, and Université Paris Descartes, Paris, France (P.-O.C.); Department of Pharmaceutical Microbiology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan (S.O.); and Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan (K.H.)
| | - Kazuhisa Fujimoto
- Division of Membrane Transport and Drug Targeting, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan (Y.K., M.T., R.A., Y.U., T.T.); Department of Applied Chemistry and Biochemistry, Faculty of Engineering, Kyushu Sangyo University, Fukuoka, Japan (K.F., M.I.); INSERM, U1016, Institut Cochin and CNRS, UMR8104, and Université Paris Descartes, Paris, France (P.-O.C.); Department of Pharmaceutical Microbiology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan (S.O.); and Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan (K.H.)
| | - Megumi Ishibashi
- Division of Membrane Transport and Drug Targeting, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan (Y.K., M.T., R.A., Y.U., T.T.); Department of Applied Chemistry and Biochemistry, Faculty of Engineering, Kyushu Sangyo University, Fukuoka, Japan (K.F., M.I.); INSERM, U1016, Institut Cochin and CNRS, UMR8104, and Université Paris Descartes, Paris, France (P.-O.C.); Department of Pharmaceutical Microbiology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan (S.O.); and Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan (K.H.)
| | - Yasuo Uchida
- Division of Membrane Transport and Drug Targeting, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan (Y.K., M.T., R.A., Y.U., T.T.); Department of Applied Chemistry and Biochemistry, Faculty of Engineering, Kyushu Sangyo University, Fukuoka, Japan (K.F., M.I.); INSERM, U1016, Institut Cochin and CNRS, UMR8104, and Université Paris Descartes, Paris, France (P.-O.C.); Department of Pharmaceutical Microbiology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan (S.O.); and Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan (K.H.)
| | - Pierre-Olivier Couraud
- Division of Membrane Transport and Drug Targeting, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan (Y.K., M.T., R.A., Y.U., T.T.); Department of Applied Chemistry and Biochemistry, Faculty of Engineering, Kyushu Sangyo University, Fukuoka, Japan (K.F., M.I.); INSERM, U1016, Institut Cochin and CNRS, UMR8104, and Université Paris Descartes, Paris, France (P.-O.C.); Department of Pharmaceutical Microbiology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan (S.O.); and Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan (K.H.)
| | - Sumio Ohtsuki
- Division of Membrane Transport and Drug Targeting, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan (Y.K., M.T., R.A., Y.U., T.T.); Department of Applied Chemistry and Biochemistry, Faculty of Engineering, Kyushu Sangyo University, Fukuoka, Japan (K.F., M.I.); INSERM, U1016, Institut Cochin and CNRS, UMR8104, and Université Paris Descartes, Paris, France (P.-O.C.); Department of Pharmaceutical Microbiology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan (S.O.); and Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan (K.H.)
| | - Ken-ichi Hosoya
- Division of Membrane Transport and Drug Targeting, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan (Y.K., M.T., R.A., Y.U., T.T.); Department of Applied Chemistry and Biochemistry, Faculty of Engineering, Kyushu Sangyo University, Fukuoka, Japan (K.F., M.I.); INSERM, U1016, Institut Cochin and CNRS, UMR8104, and Université Paris Descartes, Paris, France (P.-O.C.); Department of Pharmaceutical Microbiology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan (S.O.); and Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan (K.H.)
| | - Tetsuya Terasaki
- Division of Membrane Transport and Drug Targeting, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan (Y.K., M.T., R.A., Y.U., T.T.); Department of Applied Chemistry and Biochemistry, Faculty of Engineering, Kyushu Sangyo University, Fukuoka, Japan (K.F., M.I.); INSERM, U1016, Institut Cochin and CNRS, UMR8104, and Université Paris Descartes, Paris, France (P.-O.C.); Department of Pharmaceutical Microbiology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan (S.O.); and Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan (K.H.)
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D'hondt C, Iyyathurai J, Himpens B, Leybaert L, Bultynck G. Cx43-hemichannel function and regulation in physiology and pathophysiology: insights from the bovine corneal endothelial cell system and beyond. Front Physiol 2014; 5:348. [PMID: 25309448 PMCID: PMC4162354 DOI: 10.3389/fphys.2014.00348] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Accepted: 08/25/2014] [Indexed: 12/13/2022] Open
Abstract
Intercellular communication in primary bovine corneal endothelial cells (BCECs) is mainly driven by the release of extracellular ATP through Cx43 hemichannels. Studying the characteristics of Ca2+-wave propagation in BCECs, an important form of intercellular communication, in response to physiological signaling events has led to the discovery of important insights in the functional properties and regulation of native Cx43 hemichannels. Together with ectopic expression models for Cx43 hemichannels and truncated/mutated Cx43 versions, it became very clear that loop/tail interactions play a key role in controlling the activity of Cx43 hemichannels. Interestingly, the negative regulation of Cx43 hemichannels by enhanced actin/myosin contractility seems to impinge upon loss of these loop/tail interactions essential for opening Cx43 hemichannels. Finally, these molecular insights have spurred the development of novel peptide tools that can selectively inhibit Cx43 hemichannels, but neither Cx43 gap junctions nor hemichannels formed by other Cx isoforms. These tools now set the stage to hunt for novel physiological functions for Cx43 hemichannels in primary cells and tissues and to tackle disease conditions associated with excessive, pathological Cx43-hemichannel openings.
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Affiliation(s)
- Catheleyne D'hondt
- Laboratory of Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine, Katholieke Universiteit Leuven Leuven, Belgium
| | - Jegan Iyyathurai
- Laboratory of Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine, Katholieke Universiteit Leuven Leuven, Belgium
| | - Bernard Himpens
- Laboratory of Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine, Katholieke Universiteit Leuven Leuven, Belgium
| | - Luc Leybaert
- Physiology Group, Department of Basic Medical Sciences, Faculty of Medicine and Health Sciences, Ghent University Ghent, Belgium
| | - Geert Bultynck
- Laboratory of Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine, Katholieke Universiteit Leuven Leuven, Belgium
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Functional Role of Connexins and Pannexins in the Interaction Between Vascular and Nervous System. J Cell Physiol 2014; 229:1336-45. [DOI: 10.1002/jcp.24563] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2013] [Accepted: 01/16/2014] [Indexed: 01/22/2023]
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Vendel E, de Lange ECM. Functions of the CB1 and CB 2 receptors in neuroprotection at the level of the blood-brain barrier. Neuromolecular Med 2014; 16:620-42. [PMID: 24929655 DOI: 10.1007/s12017-014-8314-x] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2014] [Accepted: 05/14/2014] [Indexed: 12/30/2022]
Abstract
The cannabinoid (CB) receptors are the main targets of the cannabinoids, which include plant cannabinoids, endocannabinoids and synthetic cannabinoids. Over the last few years, accumulated evidence has suggested a role of the CB receptors in neuroprotection. The blood-brain barrier (BBB) is an important brain structure that is essential for neuroprotection. A link between the CB receptors and the BBB is thus likely, but this possible connection has only recently gained attention. Cannabinoids and the BBB share the same mechanisms of neuroprotection and both protect against excitotoxicity (CB1), cell death (CB1), inflammation (CB2) and oxidative stress (possibly CB independent)-all processes that also damage the BBB. Several examples of CB-mediated protection of the BBB have been found, such as inhibition of leukocyte influx and induction of amyloid beta efflux across the BBB. Moreover, the CB receptors were shown to improve BBB integrity, particularly by restoring the tightness of the tight junctions. This review demonstrated that both CB receptors are able to restore the BBB and neuroprotection, but much uncertainty about the underlying signaling cascades still exists and further investigation is needed.
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Affiliation(s)
- Esmée Vendel
- Division of Pharmacology, Leiden Academic Centre for Drug Research, Leiden University, Einsteinweg 55, 2333CC, PO Box 9502, 2300 RA, Leiden, The Netherlands
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40
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A new angle on blood-CNS interfaces: A role for connexins? FEBS Lett 2014; 588:1259-70. [DOI: 10.1016/j.febslet.2014.02.060] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Revised: 02/27/2014] [Accepted: 02/28/2014] [Indexed: 12/12/2022]
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41
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Kyan Y, Ueda Y, Yoshida M, Sasahara K, Shinya K. Transcriptome profiling of brain edemas caused by influenza infection and lipopolysaccharide treatment. J Med Virol 2013; 86:905-11. [PMID: 24306925 DOI: 10.1002/jmv.23801] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/21/2013] [Indexed: 12/11/2022]
Abstract
Influenza A virus-associated encephalopathy triggered by influenza virus infection often occurs in children aged five and younger in Japan. However, the mechanisms behind Influenza A virus-associated encephalopathy are not yet well understood. This study developed an Influenza A virus-associated encephalopathy-like model using mice infected with Influenza A virus and given lipopolysaccharide treatment. The results showed that the mice used in the model suffered from brain edemas nearly three times more severe, as well as having higher cytokine levels in sera compared to those of the control groups. Using gene expression profiling, cytokine-related genes were found not to be up-regulated in the brain in situ, while protein coding genes, which are known to be involved in blood-brain barrier disruption, were up-regulated. Categorizing the functional groups using gene ontology revealed the terms "ion channels," "calcium oscillation," and "membrane transporter activities." The blood-brain barrier disruption found in this Influenza A virus-associated encephalopathy model can therefore be assumed to be due to a cellular electrolyte imbalance of the neuronal tissue, in addition to a cytokine storm.
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Affiliation(s)
- Yukihiro Kyan
- Graduate School of Medicine, Kobe University, Hyogo, Japan
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42
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De Bock M, Kerrebrouck M, Wang N, Leybaert L. Neurological manifestations of oculodentodigital dysplasia: a Cx43 channelopathy of the central nervous system? Front Pharmacol 2013; 4:120. [PMID: 24133447 PMCID: PMC3783840 DOI: 10.3389/fphar.2013.00120] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Accepted: 09/02/2013] [Indexed: 12/30/2022] Open
Abstract
The coordination of tissue function is mediated by gap junctions (GJs) that enable direct cell–cell transfer of metabolic and electric signals. GJs are formed by connexins of which Cx43 is most widespread in the human body. In the brain, Cx43 GJs are mostly found in astroglia where they coordinate the propagation of Ca2+ waves, spatial K+ buffering, and distribution of glucose. Beyond its role in direct intercellular communication, Cx43 also forms unapposed, non-junctional hemichannels in the plasma membrane of glial cells. These allow the passage of several neuro- and gliotransmitters that may, combined with downstream paracrine signaling, complement direct GJ communication among glial cells and sustain glial-neuronal signaling. Mutations in the GJA1 gene encoding Cx43 have been identified in a rare, mostly autosomal dominant syndrome called oculodentodigital dysplasia (ODDD). ODDD patients display a pleiotropic phenotype reflected by eye, hand, teeth, and foot abnormalities, as well as craniofacial and bone malformations. Remarkably, neurological symptoms such as dysarthria, neurogenic bladder (manifested as urinary incontinence), spasticity or muscle weakness, ataxia, and epilepsy are other prominent features observed in ODDD patients. Over 10 mutations detected in patients diagnosed with neurological disorders are associated with altered functionality of Cx43 GJs/hemichannels, but the link between ODDD-related abnormal channel activities and neurologic phenotype is still elusive. Here, we present an overview on the nature of the mutants conveying structural and functional changes of Cx43 channels and discuss available evidence for aberrant Cx43 GJ and hemichannel function. In a final step, we examine the possibilities of how channel dysfunction may lead to some of the neurological manifestations of ODDD.
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Affiliation(s)
- Marijke De Bock
- Physiology Group, Department of Basic Medical Sciences, Ghent University Ghent, Belgium
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43
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Bittner S, Ruck T, Schuhmann MK, Herrmann AM, Moha ou Maati H, Bobak N, Göbel K, Langhauser F, Stegner D, Ehling P, Borsotto M, Pape HC, Nieswandt B, Kleinschnitz C, Heurteaux C, Galla HJ, Budde T, Wiendl H, Meuth SG. Endothelial TWIK-related potassium channel-1 (TREK1) regulates immune-cell trafficking into the CNS. Nat Med 2013; 19:1161-5. [PMID: 23933981 DOI: 10.1038/nm.3303] [Citation(s) in RCA: 116] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Accepted: 07/16/2013] [Indexed: 12/13/2022]
Abstract
The blood-brain barrier (BBB) is an integral part of the neurovascular unit (NVU). The NVU is comprised of endothelial cells that are interconnected by tight junctions resting on a parenchymal basement membrane ensheathed by pericytes, smooth muscle cells and a layer of astrocyte end feet. Circulating blood cells, such as leukocytes, complete the NVU. BBB disruption is common in several neurological diseases, but the molecular mechanisms involved remain largely unknown. We analyzed the role of TWIK-related potassium channel-1 (TREK1, encoded by KCNK2) in human and mouse endothelial cells and the BBB. TREK1 was downregulated in endothelial cells by treatment with interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α). Blocking TREK1 increased leukocyte transmigration, whereas TREK1 activation had the opposite effect. We identified altered mitogen-activated protein (MAP) kinase signaling, actin remodeling and upregulation of cellular adhesion molecules as potential mechanisms of increased migration in TREK1-deficient (Kcnk2(-/-)) cells. In Kcnk2(-/-) mice, brain endothelial cells showed an upregulation of the cellular adhesion molecules ICAM1, VCAM1 and PECAM1 and facilitated leukocyte trafficking into the CNS. Following the induction of experimental autoimmune encephalomyelitis (EAE) by immunization with a myelin oligodendrocyte protein (MOG)35-55 peptide, Kcnk2(-/-) mice showed higher EAE severity scores that were accompanied by increased cellular infiltrates in the central nervous system (CNS). The severity of EAE was attenuated in mice given the amyotrophic lateral sclerosis drug riluzole or fed a diet enriched with linseed oil (which contains the TREK-1 activating omega-3 fatty acid α-linolenic acid). These beneficial effects were reduced in Kcnk2(-/-) mice, suggesting TREK-1 activating compounds may be used therapeutically to treat diseases related to BBB dysfunction.
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Affiliation(s)
- Stefan Bittner
- 1] Department of Neurology, University of Münster, Münster, Germany. [2]
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44
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De Bock M, Wang N, Decrock E, Bol M, Gadicherla AK, Culot M, Cecchelli R, Bultynck G, Leybaert L. Endothelial calcium dynamics, connexin channels and blood-brain barrier function. Prog Neurobiol 2013; 108:1-20. [PMID: 23851106 DOI: 10.1016/j.pneurobio.2013.06.001] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Revised: 06/12/2013] [Accepted: 06/18/2013] [Indexed: 01/11/2023]
Abstract
Situated between the circulation and the brain, the blood-brain barrier (BBB) protects the brain from circulating toxins while securing a specialized environment for neuro-glial signaling. BBB capillary endothelial cells exhibit low transcytotic activity and a tight, junctional network that, aided by the cytoskeleton, restricts paracellular permeability. The latter is subject of extensive research as it relates to neuropathology, edema and inflammation. A key determinant in regulating paracellular permeability is the endothelial cytoplasmic Ca(2+) concentration ([Ca(2+)]i) that affects junctional and cytoskeletal proteins. Ca(2+) signals are not one-time events restricted to a single cell but often appear as oscillatory [Ca(2+)]i changes that may propagate between cells as intercellular Ca(2+) waves. The effect of Ca(2+) oscillations/waves on BBB function is largely unknown and we here review current evidence on how [Ca(2+)]i dynamics influence BBB permeability.
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Affiliation(s)
- Marijke De Bock
- Dept. of Basic Medical Sciences, Ghent University, Ghent, Belgium.
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45
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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: 3.6] [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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46
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Spray DC, Hanstein R, Lopez-Quintero SV, Stout RF, Suadicani SO, Thi MM. Gap junctions and Bystander Effects: Good Samaritans and executioners. ACTA ACUST UNITED AC 2012; 2:1-15. [PMID: 23565352 DOI: 10.1002/wmts.72] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The "Bystander" and "Good Samaritan" effects involve the transfer of toxic or beneficial compounds from one cell to a generally adjacent other through gap junction channels and through extracellular routes. The variety of injuries in which bystander cell killing or protection occurs has greatly expanded in the last decade to include infectious agents and therapeutic compounds, radiation injury, chaperones in cell therapy and apoptosis in development. This has been accompanied by the appreciation that both gap junction mediated and paracrine routes are used for the signaling of the "kiss of life" and the "kiss of death" and that manipulations of these pathways and the molecules that use them may find therapeutic utility in treatment of a variety of pathological conditions.
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Affiliation(s)
- David C Spray
- Dominick P. Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461 ; Department of Medicine, Albert Einstein College of Medicine, Bronx, NY 10461
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