1
|
Howard E, Hurrell BP, Helou DG, Shafiei-Jahani P, Hasiakos S, Painter J, Srikanth S, Gwack Y, Akbari O. Orai inhibition modulates pulmonary ILC2 metabolism and alleviates airway hyperreactivity in murine and humanized models. Nat Commun 2023; 14:5989. [PMID: 37752127 PMCID: PMC10522697 DOI: 10.1038/s41467-023-41065-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 08/22/2023] [Indexed: 09/28/2023] Open
Abstract
Ca2+ entry via Ca2+ release-activated Ca2+ (CRAC) channels is a predominant mechanism of intracellular Ca2+ elevation in immune cells. Here we show the immunoregulatory role of CRAC channel components Orai1 and Orai2 in Group 2 innate lymphoid cells (ILC2s), that play crucial roles in the induction of type 2 inflammation. We find that blocking or genetic ablation of Orai1 and Orai2 downregulates ILC2 effector function and cytokine production, consequently ameliorating the development of ILC2-mediated airway inflammation in multiple murine models. Mechanistically, ILC2 metabolic and mitochondrial homeostasis are inhibited and lead to the upregulation of reactive oxygen species production. We confirm our findings in human ILC2s, as blocking Orai1 and Orai2 prevents the development of airway hyperreactivity in humanized mice. Our findings have a broad impact on the basic understanding of Ca2+ signaling in ILC2 biology, providing potential insights into the development of therapies for the treatment of allergic and atopic inflammatory diseases.
Collapse
Affiliation(s)
- Emily Howard
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Benjamin P Hurrell
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Doumet Georges Helou
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Pedram Shafiei-Jahani
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Spyridon Hasiakos
- Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Jacob Painter
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Sonal Srikanth
- Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Yousang Gwack
- Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Omid Akbari
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA.
| |
Collapse
|
2
|
Wang YH, Noyer L, Kahlfuss S, Raphael D, Tao AY, Kaufmann U, Zhu J, Mitchell-Flack M, Sidhu I, Zhou F, Vaeth M, Thomas PG, Saunders SP, Stauderman K, Curotto de Lafaille MA, Feske S. Distinct roles of ORAI1 in T cell-mediated allergic airway inflammation and immunity to influenza A virus infection. SCIENCE ADVANCES 2022; 8:eabn6552. [PMID: 36206339 PMCID: PMC9544339 DOI: 10.1126/sciadv.abn6552] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Accepted: 08/22/2022] [Indexed: 06/16/2023]
Abstract
T cell activation and function depend on Ca2+ signals mediated by store-operated Ca2+ entry (SOCE) through Ca2+ release-activated Ca2+ (CRAC) channels formed by ORAI1 proteins. We here investigated how SOCE controls T cell function in pulmonary inflammation during a T helper 1 (TH1) cell-mediated response to influenza A virus (IAV) infection and TH2 cell-mediated allergic airway inflammation. T cell-specific deletion of Orai1 did not exacerbate pulmonary inflammation and viral burdens following IAV infection but protected mice from house dust mite-induced allergic airway inflammation. ORAI1 controlled the expression of genes including p53 and E2F transcription factors that regulate the cell cycle in TH2 cells in response to allergen stimulation and the expression of transcription factors and cytokines that regulate TH2 cell function. Systemic application of a CRAC channel blocker suppressed allergic airway inflammation without compromising immunity to IAV infection, suggesting that inhibition of SOCE is a potential treatment for allergic airway disease.
Collapse
Affiliation(s)
- Yin-Hu Wang
- Department of Pathology, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Lucile Noyer
- Department of Pathology, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Sascha Kahlfuss
- Department of Pathology, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Dimitrius Raphael
- Department of Pathology, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Anthony Y. Tao
- Department of Pathology, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Ulrike Kaufmann
- Department of Pathology, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Jingjie Zhu
- Department of Pathology, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Marisa Mitchell-Flack
- Department of Pathology, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Ikjot Sidhu
- Department of Pathology, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Fang Zhou
- Department of Pathology, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Martin Vaeth
- Department of Pathology, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Paul G. Thomas
- St. Jude’s Children’s Research Hospital, Memphis, TN 38105, USA
| | - Sean P. Saunders
- Division of Pulmonary, Critical Care and Sleep Medicine, Departments of Medicine and Cell Biology, New York University Grossman School of Medicine, NY 10016, USA
| | | | - Maria A. Curotto de Lafaille
- Division of Pulmonary, Critical Care and Sleep Medicine, Departments of Medicine and Cell Biology, New York University Grossman School of Medicine, NY 10016, USA
| | - Stefan Feske
- Department of Pathology, New York University Grossman School of Medicine, New York, NY 10016, USA
| |
Collapse
|
3
|
Title: p53 alters intracellular Ca2+ signaling through regulation of TRPM4. Cell Calcium 2022; 104:102591. [DOI: 10.1016/j.ceca.2022.102591] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Revised: 04/08/2022] [Accepted: 04/18/2022] [Indexed: 12/11/2022]
|
4
|
Maltan L, Najjar H, Tiffner A, Derler I. Deciphering Molecular Mechanisms and Intervening in Physiological and Pathophysiological Processes of Ca 2+ Signaling Mechanisms Using Optogenetic Tools. Cells 2021; 10:3340. [PMID: 34943850 PMCID: PMC8699489 DOI: 10.3390/cells10123340] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 11/17/2021] [Accepted: 11/22/2021] [Indexed: 11/16/2022] Open
Abstract
Calcium ion channels are involved in numerous biological functions such as lymphocyte activation, muscle contraction, neurotransmission, excitation, hormone secretion, gene expression, cell migration, memory, and aging. Therefore, their dysfunction can lead to a wide range of cellular abnormalities and, subsequently, to diseases. To date various conventional techniques have provided valuable insights into the roles of Ca2+ signaling. However, their limited spatiotemporal resolution and lack of reversibility pose significant obstacles in the detailed understanding of the structure-function relationship of ion channels. These drawbacks could be partially overcome by the use of optogenetics, which allows for the remote and well-defined manipulation of Ca2+-signaling. Here, we review the various optogenetic tools that have been used to achieve precise control over different Ca2+-permeable ion channels and receptors and associated downstream signaling cascades. We highlight the achievements of optogenetics as well as the still-open questions regarding the resolution of ion channel working mechanisms. In addition, we summarize the successes of optogenetics in manipulating many Ca2+-dependent biological processes both in vitro and in vivo. In summary, optogenetics has significantly advanced our understanding of Ca2+ signaling proteins and the used tools provide an essential basis for potential future therapeutic application.
Collapse
Affiliation(s)
| | | | | | - Isabella Derler
- Institute of Biophysics, JKU Life Science Center, Johannes Kepler University Linz, A-4020 Linz, Austria; (L.M.); (H.N.); (A.T.)
| |
Collapse
|
5
|
Filho EGF, da Silva EZM, Ong HL, Swaim WD, Ambudkar IS, Oliver C, Jamur MC. RACK1 plays a critical role in mast cell secretion and Ca2+ mobilization by modulating F-actin dynamics. J Cell Sci 2021; 134:263932. [PMID: 34550354 DOI: 10.1242/jcs.252585] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Accepted: 03/15/2021] [Indexed: 11/20/2022] Open
Abstract
Although RACK1 is known to act as a signaling hub in immune cells, its presence and role in mast cells (MCs) is undetermined. MC activation via antigen stimulation results in mediator release and is preceded by cytoskeleton reorganization and Ca2+ mobilization. In this study, we found that RACK1 was distributed throughout the MC cytoplasm both in vivo and in vitro. After RACK1 knockdown (KD), MCs were rounded, and the cortical F-actin was fragmented. Following antigen stimulation, in RACK1 KD MCs, there was a reduction in cortical F-actin, an increase in monomeric G-actin and a failure to organize F-actin. RACK1 KD also increased and accelerated degranulation. CD63+ secretory granules were localized in F-actin-free cortical regions in non-stimulated RACK1 KD MCs. Additionally, RACK1 KD increased antigen-stimulated Ca2+ mobilization, but attenuated antigen-stimulated depletion of ER Ca2+ stores and thapsigargin-induced Ca2+ entry. Following MC activation there was also an increase in interaction of RACK1 with Orai1 Ca2+-channels, β-actin and the actin-binding proteins vinculin and MyoVa. These results show that RACK1 is a critical regulator of actin dynamics, affecting mediator secretion and Ca2+ signaling in MCs. This article has an associated First Person interview with the first author of the paper.
Collapse
Affiliation(s)
- Edismauro G Freitas Filho
- Department of Cell and Molecular Biology and Pathogenic Bioagents, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Av. Bandeirantes 3900, Ribeirão Preto, SP 14049-900, Brazil
| | - Elaine Z M da Silva
- Department of Cell and Molecular Biology and Pathogenic Bioagents, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Av. Bandeirantes 3900, Ribeirão Preto, SP 14049-900, Brazil
| | - Hwei Ling Ong
- Secretory Physiology Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892, USA
| | - William D Swaim
- Secretory Physiology Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892, USA
| | - Indu S Ambudkar
- Secretory Physiology Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892, USA
| | - Constance Oliver
- Department of Cell and Molecular Biology and Pathogenic Bioagents, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Av. Bandeirantes 3900, Ribeirão Preto, SP 14049-900, Brazil
| | - Maria Célia Jamur
- Department of Cell and Molecular Biology and Pathogenic Bioagents, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Av. Bandeirantes 3900, Ribeirão Preto, SP 14049-900, Brazil
| |
Collapse
|
6
|
Jansen C, Shimoda LMN, Starkus J, Lange I, Rysavy N, Maaetoft-Udsen K, Tobita C, Stokes AJ, Turner H. In vitro exposure to Hymenoptera venom and constituents activates discrete ionotropic pathways in mast cells. Channels (Austin) 2020; 13:264-286. [PMID: 31237176 PMCID: PMC8670737 DOI: 10.1080/19336950.2019.1629225] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Calcium entry is central to the functional processes in mast cells and basophils that contribute to the induction and maintenance of inflammatory responses. Mast cells and basophils express an array of calcium channels, which mediate responses to diverse stimuli triggered by small bioactive molecules, physicochemical stimuli and immunological inputs including antigens and direct immune cell interactions. These cells are also highly responsive to certain venoms (such as Hymenoptera envenomations), which cause histamine secretion, cytokine release and an array of pro-inflammatory functional responses. There are gaps in our understanding of the coupling of venom exposure to specific signaling pathways such as activation of calcium channels. In the present study, we performed a current survey of a model mast cell line selected for its pleiotropic responsiveness to multiple pro-inflammatory inputs. As a heterogenous stimulus, Hymenoptera venom activates multiple classes of conductance at the population level but tend to lead to the measurement of only one type of conductance per cell, despite the cell co-expressing multiple channel types. The data show that ICRAC, IARC, and TRPV-like currents are present in the model mast cell populations and respond to venom exposure. We further assessed individual venom components, specifically secretagogues and arachidonic acid, and identified the conductances associated with these stimuli in mast cells. Single-cell calcium assays and immunofluorescence analysis show that there is heterogeneity of channel expression across the cell population, but this heterogeneity does not explain the apparent selectivity for specific channels in response to exposure to venom as a composite stimulus.
Collapse
Affiliation(s)
- C Jansen
- a Laboratory of Immunology and Signal Transduction, Division of Natural Sciences and Mathematics , Chaminade University , Honolulu , Hawai'I , USA
| | - L M N Shimoda
- a Laboratory of Immunology and Signal Transduction, Division of Natural Sciences and Mathematics , Chaminade University , Honolulu , Hawai'I , USA
| | - J Starkus
- a Laboratory of Immunology and Signal Transduction, Division of Natural Sciences and Mathematics , Chaminade University , Honolulu , Hawai'I , USA
| | - I Lange
- b Department of Pharmaceutical Sciences , Daniel K. Inouye College of Pharmacy, University of Hawai'i at Hilo , Hilo , Hawai'i , USA
| | - N Rysavy
- a Laboratory of Immunology and Signal Transduction, Division of Natural Sciences and Mathematics , Chaminade University , Honolulu , Hawai'I , USA
| | - K Maaetoft-Udsen
- a Laboratory of Immunology and Signal Transduction, Division of Natural Sciences and Mathematics , Chaminade University , Honolulu , Hawai'I , USA
| | - C Tobita
- a Laboratory of Immunology and Signal Transduction, Division of Natural Sciences and Mathematics , Chaminade University , Honolulu , Hawai'I , USA
| | - A J Stokes
- c Department of Cell and Molecular Biology, Laboratory of Experimental Medicine, John A. Burns School of Medicine , University of Hawai'i , Honolulu , Hawai'i , USA
| | - H Turner
- a Laboratory of Immunology and Signal Transduction, Division of Natural Sciences and Mathematics , Chaminade University , Honolulu , Hawai'I , USA
| |
Collapse
|
7
|
Kappel S, Borgström A, Stokłosa P, Dörr K, Peinelt C. Store-operated calcium entry in disease: Beyond STIM/Orai expression levels. Semin Cell Dev Biol 2019; 94:66-73. [PMID: 30630032 DOI: 10.1016/j.semcdb.2019.01.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Revised: 11/29/2018] [Accepted: 01/05/2019] [Indexed: 12/19/2022]
Abstract
Precise intracellular calcium signaling is crucial to numerous cellular functions. In non-excitable cells, store-operated calcium entry (SOCE) is a key step in the generation of intracellular calcium signals. Tight regulation of SOCE is important, and dysregulation is involved in several pathophysiological cellular malfunctions. The current underlying SOCE, calcium release-activated calcium current (ICRAC), was first discovered almost three decades ago. Since its discovery, the molecular components of ICRAC, Orai1 and stromal interaction molecule 1 (STIM1), have been extensively investigated. Several regulatory mechanisms and proteins contribute to alterations in SOCE and cellular malfunctions in cancer, immune and neurodegenerative diseases, inflammation, and neuronal disorders. This review summarizes these regulatory mechanisms, including glycosylation, pH sensing, and the regulatory proteins golli, α-SNAP, SARAF, ORMDL3, CRACR2A, and TRPM4 channels.
Collapse
Affiliation(s)
- Sven Kappel
- Institute of Biochemistry and Molecular Medicine, National Center of Competence in Research NCCR TransCure, University of Bern, Bühlstrasse 28, 3012 Bern, Switzerland
| | - Anna Borgström
- Institute of Biochemistry and Molecular Medicine, National Center of Competence in Research NCCR TransCure, University of Bern, Bühlstrasse 28, 3012 Bern, Switzerland
| | - Paulina Stokłosa
- Institute of Biochemistry and Molecular Medicine, National Center of Competence in Research NCCR TransCure, University of Bern, Bühlstrasse 28, 3012 Bern, Switzerland
| | | | - Christine Peinelt
- Institute of Biochemistry and Molecular Medicine, National Center of Competence in Research NCCR TransCure, University of Bern, Bühlstrasse 28, 3012 Bern, Switzerland.
| |
Collapse
|
8
|
Yi MH, Kim HP, Jeong KY, Kim JY, Lee IY, Yong TS. Effects of the Th2-dominant milieu on allergic responses in Der f 1-activated mouse basophils and mast cells. Sci Rep 2018; 8:7706. [PMID: 29769546 PMCID: PMC5955989 DOI: 10.1038/s41598-018-25741-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Accepted: 04/23/2018] [Indexed: 12/25/2022] Open
Abstract
Although basophils and mast cells share similar phenotypic and functional properties, little is known about the difference in the initial Th2 immune responses of these cells following exposure to proteolytic allergens. Here, we investigated the mechanisms of Th2-mediated immune responses in mouse bone marrow-derived basophils (BMBs) and mast cells (BMMCs) via stimulation with the cysteine protease allergen Der f 1. Our results showed that Th2 cytokines were induced from BMBs by active recombinant Der f 1 (rDer f 1 independently with Toll-like receptor (TLR) 2 and TLR4. Although both BMBs and BMMCs expressed protease-activated receptors on their surfaces, PAR expression following exposure to rDer f 1 was altered only in basophils. G protein-coupled receptors in basophils were found to be associated with interleukin (IL)-4 and IL-13 production from BMBs upon Der f 1 treatment. Secretion of Th2 cytokines from rDer f 1-treated basophils was mediated by G protein βγ and phosphatidylinositol 3-kinase γ through the extracellular signal-regulated kinase and c-Jun N-terminal kinase pathways. These findings provide insights into the roles of cysteine proteases in Th2 immune responses, such as allergic diseases, and improve our understanding of the mechanisms of Th2 cytokine production.
Collapse
Affiliation(s)
- Myung-Hee Yi
- Department of Environmental Medical Biology, Arthropods of Medical Importance Resource Bank, Institute of Tropical Medicine, Yonsei University College of Medicine, Seoul, 03722, Korea
| | - Hyoung-Pyo Kim
- Department of Environmental Medical Biology, Arthropods of Medical Importance Resource Bank, Institute of Tropical Medicine, Yonsei University College of Medicine, Seoul, 03722, Korea.,Graduate Program of Nano Science and Technology, Yonsei University College of Medicine, Seoul, 03722, Korea.,Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul, 03722, Korea.,BK21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, 03722, Korea
| | - Kyoung Yong Jeong
- Department of Internal Medicine, Institute of Allergy, Yonsei University College of Medicine, Seoul, Korea
| | - Ju Yeong Kim
- Department of Environmental Medical Biology, Arthropods of Medical Importance Resource Bank, Institute of Tropical Medicine, Yonsei University College of Medicine, Seoul, 03722, Korea
| | - In-Yong Lee
- Department of Environmental Medical Biology, Arthropods of Medical Importance Resource Bank, Institute of Tropical Medicine, Yonsei University College of Medicine, Seoul, 03722, Korea
| | - Tai-Soon Yong
- Department of Environmental Medical Biology, Arthropods of Medical Importance Resource Bank, Institute of Tropical Medicine, Yonsei University College of Medicine, Seoul, 03722, Korea.
| |
Collapse
|
9
|
Gryshchenko O, Gerasimenko JV, Peng S, Gerasimenko OV, Petersen OH. Calcium signalling in the acinar environment of the exocrine pancreas: physiology and pathophysiology. J Physiol 2018; 596:2663-2678. [PMID: 29424931 PMCID: PMC6046068 DOI: 10.1113/jp275395] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Accepted: 01/25/2018] [Indexed: 12/12/2022] Open
Abstract
Key points Ca2+ signalling in different cell types in exocrine pancreatic lobules was monitored simultaneously and signalling responses to various stimuli were directly compared. Ca2+ signals evoked by K+‐induced depolarization were recorded from pancreatic nerve cells. Nerve cell stimulation evoked Ca2+ signals in acinar but not in stellate cells. Stellate cells are not electrically excitable as they, like acinar cells, did not generate Ca2+ signals in response to membrane depolarization. The responsiveness of the stellate cells to bradykinin was markedly reduced in experimental alcohol‐related acute pancreatitis, but they became sensitive to stimulation with trypsin. Our results provide fresh evidence for an important role of stellate cells in acute pancreatitis. They seem to be a critical element in a vicious circle promoting necrotic acinar cell death. Initial trypsin release from a few dying acinar cells generates Ca2+ signals in the stellate cells, which then in turn damage more acinar cells causing further trypsin liberation.
Abstract Physiological Ca2+ signals in pancreatic acinar cells control fluid and enzyme secretion, whereas excessive Ca2+ signals induced by pathological agents induce destructive processes leading to acute pancreatitis. Ca2+ signals in the peri‐acinar stellate cells may also play a role in the development of acute pancreatitis. In this study, we explored Ca2+ signalling in the different cell types in the acinar environment of the pancreatic tissue. We have, for the first time, recorded depolarization‐evoked Ca2+ signals in pancreatic nerves and shown that whereas acinar cells receive a functional cholinergic innervation, there is no evidence for functional innervation of the stellate cells. The stellate, like the acinar, cells are not electrically excitable as they do not generate Ca2+ signals in response to membrane depolarization. The principal agent evoking Ca2+ signals in the stellate cells is bradykinin, but in experimental alcohol‐related acute pancreatitis, these cells become much less responsive to bradykinin and then acquire sensitivity to trypsin. Our new findings have implications for our understanding of the development of acute pancreatitis and we propose a scheme in which Ca2+ signals in stellate cells provide an amplification loop promoting acinar cell death. Initial release of the proteases kallikrein and trypsin from dying acinar cells can, via bradykinin generation and protease‐activated receptors, induce Ca2+ signals in stellate cells which can then, possibly via nitric oxide generation, damage more acinar cells and thereby cause additional release of proteases, generating a vicious circle. Ca2+ signalling in different cell types in exocrine pancreatic lobules was monitored simultaneously and signalling responses to various stimuli were directly compared. Ca2+ signals evoked by K+‐induced depolarization were recorded from pancreatic nerve cells. Nerve cell stimulation evoked Ca2+ signals in acinar but not in stellate cells. Stellate cells are not electrically excitable as they, like acinar cells, did not generate Ca2+ signals in response to membrane depolarization. The responsiveness of the stellate cells to bradykinin was markedly reduced in experimental alcohol‐related acute pancreatitis, but they became sensitive to stimulation with trypsin. Our results provide fresh evidence for an important role of stellate cells in acute pancreatitis. They seem to be a critical element in a vicious circle promoting necrotic acinar cell death. Initial trypsin release from a few dying acinar cells generates Ca2+ signals in the stellate cells, which then in turn damage more acinar cells causing further trypsin liberation.
Collapse
Affiliation(s)
- Oleksiy Gryshchenko
- Cardiff School of Biosciences, Cardiff University, Cardiff CF10 3AX, UK.,Bogomoletz Institute of Physiology, Kyiv 01024, Ukraine
| | | | - Shuang Peng
- Cardiff School of Biosciences, Cardiff University, Cardiff CF10 3AX, UK.,Department of Physiology, Medical College, Jinan University, Guangzhou 510632, China
| | | | - Ole H Petersen
- Cardiff School of Biosciences, Cardiff University, Cardiff CF10 3AX, UK.,Systems Immunity Research Institute, Cardiff University, Cardiff, CF14 4XN, UK
| |
Collapse
|
10
|
Joskova M, Sutovska M, Durdik P, Koniar D, Hargas L, Banovcin P, Hrianka M, Khazaei V, Pappova L, Franova S. The Role of Ion Channels to Regulate Airway Ciliary Beat Frequency During Allergic Inflammation. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 921:27-35. [PMID: 27369295 DOI: 10.1007/5584_2016_247] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Overproduction of mucus is a hallmark of asthma. The aim of this study was to identify potentially effective therapies for removing excess mucus. The role of voltage-gated (Kir 6.1, KCa 1.1) and store-operated ion channels (SOC, CRAC) in respiratory cilia, relating to the tracheal ciliary beat frequency (CBF), was compared under the physiological and allergic airway conditions. Ex vivo experiments were designed to test the local effects of Kir 6.1, KCa 1.1 and CRAC ion channel modulators in a concentration-dependent manner on the CBF. Cilia, obtained with the brushing method, were monitored by a high-speed video camera and analyzed with ciliary analysis software. In natural conditions, a Kir 6.1 opener accelerated CBF, while CRAC blocker slowed it in a concentration-dependent manner. In allergic inflammation, the effect of Kir 6.1 opener was insignificant, with a tendency to decrease CBF. A cilio-inhibitory effect of a CRAC blocker, while gently reduced by allergic inflammation, remained significant. A KCa 1.1 opener turned out to significantly enhance the CBF under the allergic OVA-sensitized conditions. We conclude that optimally attuned concentration of KCa 1.1 openers or special types of bimodal SOC channel blockers, potentially given by inhalation, might benefit asthma.
Collapse
Affiliation(s)
- M Joskova
- Department of Pharmacology, BioMed Martin, Jessenius Faculty of Medicine, Comenius University in Bratislava, 4C Mala Hora St, 036 01, Martin, Slovakia.
| | - M Sutovska
- Department of Pharmacology, BioMed Martin, Jessenius Faculty of Medicine, Comenius University in Bratislava, 4C Mala Hora St, 036 01, Martin, Slovakia
| | - P Durdik
- Department of Children and Adolescents, Jessenius Faculty of Medicine, Comenius University in Bratislava and Martin University Hospital, 2 Kollarova St, 036 01, Martin, Slovakia
| | - D Koniar
- Department of Mechatronics and Electronics, Faculty of Electrical Engineering, University of Zilina, 1 Univerzitna St, 010 26, Zilina, Slovakia
| | - L Hargas
- Department of Mechatronics and Electronics, Faculty of Electrical Engineering, University of Zilina, 1 Univerzitna St, 010 26, Zilina, Slovakia
| | - P Banovcin
- Department of Children and Adolescents, Jessenius Faculty of Medicine, Comenius University in Bratislava and Martin University Hospital, 2 Kollarova St, 036 01, Martin, Slovakia
| | - M Hrianka
- Department of Mechatronics and Electronics, Faculty of Electrical Engineering, University of Zilina, 1 Univerzitna St, 010 26, Zilina, Slovakia
| | - V Khazaei
- Department of Pharmacology, BioMed Martin, Jessenius Faculty of Medicine, Comenius University in Bratislava, 4C Mala Hora St, 036 01, Martin, Slovakia
| | - L Pappova
- Department of Pharmacology, BioMed Martin, Jessenius Faculty of Medicine, Comenius University in Bratislava, 4C Mala Hora St, 036 01, Martin, Slovakia
| | - S Franova
- Department of Pharmacology, BioMed Martin, Jessenius Faculty of Medicine, Comenius University in Bratislava, 4C Mala Hora St, 036 01, Martin, Slovakia
| |
Collapse
|
11
|
Nam JH, Jung HW, Chin YW, Yang WM, Bae HS, Kim WK. Spirodela polyrhiza extract modulates the activation of atopic dermatitis-related ion channels, Orai1 and TRPV3, and inhibits mast cell degranulation. PHARMACEUTICAL BIOLOGY 2017; 55:1324-1329. [PMID: 28290212 PMCID: PMC6130684 DOI: 10.1080/13880209.2017.1300819] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Revised: 11/25/2016] [Accepted: 01/25/2017] [Indexed: 06/06/2023]
Abstract
CONTEXT Spirodela polyrhiza (L.) Schleid. (Lemnaceae), Spirodelae Herba (SH), has been known to relieve inflammation, urticaria and skin symptoms including pruritus, eczema and rash. OBJECTIVE The effects of SH extract on two calcium ion channels, Orai1 and TRPV3, and their potential as novel therapeutics for atopic dermatitis (AD) were investigated. The regulatory role of Orai1 on mast cell degranulation was evaluated. MATERIALS AND METHODS The dried leaves of SH were extracted by 70% methanol. Effects of SH extract (100 μg/mL) in an HEK293T cell line overexpressing human Orai1 or TRPV3 were assessed. Ion channel modulation in transfected HEK293T cells was measured using a conventional whole-cell patch-clamp technique. IgE-antigen complex-stimulated mast cell degranulation was measured by β-hexosaminidase assay with morphological observation after treatment with 20, 50 and 100 μg/mL SH extract. RESULTS SH extract (100 μg/mL) significantly inhibited Orai1 activity (63.8 ± 0.97%) in Orai1-STIM1 co-overexpressed HEK293T cells. SH extract significantly increased TRPV3 activity (81.29 ± 0.05% at -100 mV) compared with the positive control 2-APB (100 μM), which induced full activation. SH extract inhibited degranulation in IgE-antigen complex-stimulated RBL-2H3 mast cells by decreasing β-hexosaminidase activity (3.14 ± 0.03, 2.56 ± 0.12 and 2.29 ± 0.08 mU/mg, respectively). CONCLUSION Our results suggested that SH extract could treat abnormal skin barrier pathologies in AD through modulation of the activities of the calcium ion channels Orai1 and TRPV3 and inhibition of mast cell degranulation. This is the first report of an herbal effect on the modulation of ion channels associated with skin barrier disruption in AD pathogenesis.
Collapse
Affiliation(s)
- Joo Hyun Nam
- Department of Physiology, Dongguk University College of Medicine, Gyeongju, Republic of Korea
- Channelopathy Research Center (CRC), Dongguk University College of Medicine, Goyang, Gyeonggi-do, Republic of Korea
| | - Hyo Won Jung
- College of Korean Medicine, Dongguk University, Gyeongju, Republic of Korea
| | - Young-Won Chin
- College of Pharmacy, Dongguk University, Goyang, Gyeonggi-do, Republic of Korea
| | - Won-Mo Yang
- Department of Biochemistry, Dongguk University College of Medicine, Gyeongju, Republic of Korea
| | - Hyo Sang Bae
- Department of Sasang Constitutional Medicine, College of Korean Medicine, Dongguk University, Goyang, Gyeonggi-do, Republic of Korea
| | - Woo Kyung Kim
- Channelopathy Research Center (CRC), Dongguk University College of Medicine, Goyang, Gyeonggi-do, Republic of Korea
- Department of Internal Medicine, Graduate School of Medicine, Dongguk University, Goyang, Gyeonggi-do, Republic of Korea
| |
Collapse
|
12
|
Bai S, Nagai M, Koerner SK, Veves A, Sun L. Structure-activity relationship study and discovery of indazole 3-carboxamides as calcium-release activated calcium channel blockers. Bioorg Med Chem Lett 2017; 27:393-397. [PMID: 28057422 PMCID: PMC5271583 DOI: 10.1016/j.bmcl.2016.12.062] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Revised: 12/23/2016] [Accepted: 12/24/2016] [Indexed: 02/04/2023]
Abstract
Aberrant activation of mast cells contributes to the development of numerous diseases including cancer, autoimmune disorders, as well as diabetes and its complications. The influx of extracellular calcium via the highly calcium selective calcium-release activated calcium (CRAC) channel controls mast cell functions. Intracellular calcium homeostasis in mast cells can be maintained via the modulation of the CRAC channel, representing a critical point for therapeutic interventions. We describe the structure-activity relationship study (SAR) of indazole-3-carboxamides as potent CRAC channel blockers and their ability to stabilize mast cells. Our SAR results show that the unique regiochemistry of the amide linker is critical for the inhibition of calcium influx, the release of the pro-inflammatory mediators β-hexosaminidase and tumor necrosis factor α by activated mast cells. Thus, the indazole-3-carboxamide 12d actively inhibits calcium influx and stabilizes mast cells with sub-μM IC50. In contrast, its reverse amide isomer 9c is inactive in the calcium influx assay even at 100μM concentration. This requirement of the specific 3-carboxamide regiochemistry in indazoles is unprecedented in known CRAC channel blockers. The new structural scaffolds described in this report expand the structural diversity of the CRAC channel blockers and may lead to the discovery of novel immune modulators for the treatment of human diseases.
Collapse
Affiliation(s)
- Sha Bai
- Center for Drug Discovery and Translational Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Masazumi Nagai
- Center for Drug Discovery and Translational Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Steffi K Koerner
- Center for Drug Discovery and Translational Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Aristidis Veves
- The Rongxiang Xu, MD Center for Regenerative Therapeutics, Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Lijun Sun
- Center for Drug Discovery and Translational Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA.
| |
Collapse
|
13
|
Sun R, Yang Y, Ran X, Yang T. Calcium Influx of Mast Cells Is Inhibited by Aptamers Targeting the First Extracellular Domain of Orai1. PLoS One 2016; 11:e0158223. [PMID: 27390850 PMCID: PMC4938386 DOI: 10.1371/journal.pone.0158223] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Accepted: 06/13/2016] [Indexed: 12/17/2022] Open
Abstract
Using the systematic evolution of ligands by exponential enrichment (SELEX) method, we identified oligonucleotides that bind to the first extracellular domain of the Orai1 protein with high affinities and high specificities. These ligands were isolated from a random single-strand DNA (ssDNA) library with 40 randomized sequence positions, using synthesized peptides with amino acid sequences identical to the first extracellular domain of the Orai1 protein as the targets for SELEX selection. Seven aptamers were obtained after 12 rounds of SELEX. An enzyme-linked oligonucleotide assay (ELONA) was performed to determine the affinities of the aptamers. Aptamer Y1 had the highest affinity (Kd = 1.72×10−8 mol/L) and was selected for functional experiments in mast cells. Using LAD2 cells with the human high-affinity IgE receptor and Ca2+ release activation channel (CRAC), we demonstrated that Aptamer Y1 blocked IgE-mediated β-hexosaminidase release from cells triggered by biotin-IgE and streptavidin. A specific binding assay showed that Aptamer Y1 not only bound the Orai1 peptide specifically but also that the Orai1 peptide did not bind significantly to other random oligonucleotide molecules. Furthermore, Aptamer Y1 regulation of intracellular Ca2+ mobilization was investigated by probing intracellular Ca2+ with a Fluo-4-AM fluorescent probe. We found that Aptamer Y1 inhibits Ca2+ influx into antigen-activated mast cells. These results indicate that the target of Aptamer Y1 in the degranulation pathway is upstream of Ca2+ influx. Therefore, these oligonucleotide agents represent a novel class of CRAC inhibitors that may be useful in the fight against allergic diseases.
Collapse
Affiliation(s)
- Renshan Sun
- Department of Dermatology, Institute of Battle Surgery, Daping Hospital, Third Military Medical University, Chongqing, 400042, China
- * E-mail:
| | - Yongqiang Yang
- Department of Dermatology, Institute of Battle Surgery, Daping Hospital, Third Military Medical University, Chongqing, 400042, China
| | - Xinze Ran
- Institute of Combined Injury, College of Military Preventive Medicine, Third Military Medical University, Chongqing, 400038, China
| | - Tao Yang
- Department of Dermatology, Institute of Battle Surgery, Daping Hospital, Third Military Medical University, Chongqing, 400042, China
| |
Collapse
|
14
|
Papaioannou NE, Voutsas IF, Samara P, Tsitsilonis OE. A flow cytometric approach for studying alterations in the cytoplasmic concentration of calcium ions in immune cells following stimulation with thymic peptides. Cell Immunol 2016; 302:32-40. [DOI: 10.1016/j.cellimm.2016.01.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 12/10/2015] [Accepted: 01/06/2016] [Indexed: 11/29/2022]
|
15
|
Dörr K, Kilch T, Kappel S, Alansary D, Schwär G, Niemeyer BA, Peinelt C. Cell type-specific glycosylation of Orai1 modulates store-operated Ca2+ entry. Sci Signal 2016; 9:ra25. [PMID: 26956484 DOI: 10.1126/scisignal.aaa9913] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
N-glycosylation of cell surface proteins affects protein function, stability, and interaction with other proteins. Orai channels, which mediate store-operated Ca(2+) entry (SOCE), are composed of N-glycosylated subunits. Upon activation by Ca(2+) sensor proteins (stromal interaction molecules STIM1 or STIM2) in the endoplasmic reticulum, Orai Ca(2+) channels in the plasma membrane mediate Ca(2+) influx. Lectins are carbohydrate-binding proteins, and Siglecs are a family of sialic acid-binding lectins with immunoglobulin-like repeats. Using Western blot analysis and lectin-binding assays from various primary human cells and cancer cell lines, we found that glycosylation of Orai1 is cell type-specific. Ca(2+) imaging experiments and patch-clamp experiments revealed that mutation of the only glycosylation site of Orai1 (Orai1N223A) enhanced SOCE in Jurkat T cells. Knockdown of the sialyltransferase ST6GAL1 reduced α-2,6-linked sialic acids in the glycan structure of Orai1 and was associated with increased Ca(2+) entry in Jurkat T cells. In human mast cells, inhibition of sialyl sulfation altered the N-glycan of Orai1 (and other proteins) and increased SOCE. These data suggest that cell type-specific glycosylation influences the interaction of Orai1 with specific lectins, such as Siglecs, which then attenuates SOCE. In summary, the glycosylation state of Orai1 influences SOCE-mediated Ca(2+) signaling and, thus, may contribute to pathophysiological Ca(2+) signaling observed in immune disease and cancer.
Collapse
Affiliation(s)
- Kathrin Dörr
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg 66421, Germany. Molecular Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg 66421, Germany. Center of Human and Molecular Biology, Saarland University, Homburg 66421, Germany
| | - Tatiana Kilch
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg 66421, Germany. Center of Human and Molecular Biology, Saarland University, Homburg 66421, Germany
| | - Sven Kappel
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg 66421, Germany. Center of Human and Molecular Biology, Saarland University, Homburg 66421, Germany
| | - Dalia Alansary
- Molecular Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg 66421, Germany
| | - Gertrud Schwär
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg 66421, Germany. Molecular Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg 66421, Germany
| | - Barbara A Niemeyer
- Molecular Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg 66421, Germany
| | - Christine Peinelt
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg 66421, Germany. Center of Human and Molecular Biology, Saarland University, Homburg 66421, Germany.
| |
Collapse
|
16
|
Calcium signalling in pancreatic stellate cells: Mechanisms and potential roles. Cell Calcium 2016; 59:140-4. [DOI: 10.1016/j.ceca.2016.02.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Accepted: 02/05/2016] [Indexed: 11/22/2022]
|
17
|
Sutovska M, Kocmalova M, Franova S, Vakkalanka S, Viswanadha S. Pharmacodynamic evaluation of RP3128, a novel and potent CRAC channel inhibitor in guinea pig models of allergic asthma. Eur J Pharmacol 2015; 772:62-70. [PMID: 26724844 DOI: 10.1016/j.ejphar.2015.12.047] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Revised: 12/23/2015] [Accepted: 12/23/2015] [Indexed: 10/22/2022]
Abstract
The increase in intracellular Ca(2+) levels through the activation of Ca(2+) release-activated Ca(2+) (CRAC) channels is essential for mediating a wide scale of immune cell responses. Emerging evidence indicates an involvement of abnormal CRAC channel activity in human diseases such as certain types of immunodeficiency, autoimmunity and allergic disorders. This objective of this study was to evaluate the therapeutic potency of a novel CRAC channel inhibitor, RP3128, in experimental models of allergic asthma using guinea pigs. Ovalbumin-induced allergic airway inflammation was determined upon acute and long-term (14 days) oral administration of RP3128. In vivo changes in specific airways resistance (sRaw) and amplitude of isometric contraction (mN) of ASM (in vitro) were estimated to evaluate bronchodilatory effect upon acute and long-term administration of RP3128 or salbutamol. Exhaled nitric oxide (eNO), immunohistochemical and histological analysis of cellular infiltration in airways tissue, and levels of cytokines in plasma as well as bronchoalveolar lavage fluid (BALF), were determined using Bio-Plex® 200 System (BIO-RAD, USA). Ciliary beat frequency (CBF, in Hz) was estimated using a high-speed video camera and LabVIEW™ Software. Additionally, the impact of RP3128 and budesonide on mucociliary clearance was determined. Acute and long-term administration of RP3128 resulted in significant bronchodilation. Long-term administration of RP3128 exceeded the bronchodilatory effect of salbutamol and significantly decreased eNO and cytokine levels in plasma and BALF, which together with histological and immunohistochemical analysis validated its anti-inflammatory effect compared to budesonide. Data demonstrate the therapeutic potential of RP3128 in respiratory diseases causally associated with allergic inflammation.
Collapse
Affiliation(s)
- Martina Sutovska
- Department of Pharmacology, Jessenius Faculty of Medicine, Comenius University, Martin's Biomedical Center (BioMed) Malá Hora, 11161 4D Martin, Slovakia
| | - Michaela Kocmalova
- Department of Pharmacology, Jessenius Faculty of Medicine, Comenius University, Martin's Biomedical Center (BioMed) Malá Hora, 11161 4D Martin, Slovakia
| | - Sona Franova
- Department of Pharmacology, Jessenius Faculty of Medicine, Comenius University, Martin's Biomedical Center (BioMed) Malá Hora, 11161 4D Martin, Slovakia
| | | | - Srikant Viswanadha
- Incozen Therapeutics Pvt. Ltd., 450, Alexandria Knowledge Park, Shameerpet, Hyderabad, India.
| |
Collapse
|
18
|
Discovery and structural optimization of 1-phenyl-3-(1-phenylethyl)urea derivatives as novel inhibitors of CRAC channel. Acta Pharmacol Sin 2015; 36:1137-44. [PMID: 26256403 DOI: 10.1038/aps.2015.52] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2015] [Accepted: 04/27/2015] [Indexed: 02/05/2023] Open
Abstract
AIM Ca(2+)-release-activated Ca(2+) (CRAC) channel, a subfamily of store-operated channels, is formed by calcium release-activated calcium modulator 1 (ORAI1), and gated by stromal interaction molecule 1 (STIM1). CRAC channel may be a novel target for the treatment of immune disorders and allergy. The aim of this study was to identify novel small molecule CRAC channel inhibitors. METHODS HEK293 cells stably co-expressing both ORAI1 and STIM1 were used for high-throughput screening. A hit, 1-phenyl-3-(1-phenylethyl)urea, was identified that inhibited CRAC channels by targeting ORAI1. Five series of its derivatives were designed and synthesized, and their primary structure-activity relationships (SARs) were analyzed. All derivatives were assessed for their effects on Ca(2+) influx through CRAC channels on HEK293 cells, cytotoxicity in Jurkat cells, and IL-2 production in Jurkat cells expressing ORAI1-SS-eGFP. RESULTS A total of 19 hits were discovered in libraries containing 32 000 compounds using the high-throughput screening. 1-Phenyl-3-(1-phenylethyl)urea inhibited Ca(2+) influx with IC50 of 3.25±0.17 μmol/L. SAR study on its derivatives showed that the alkyl substituent on the α-position of the left-side benzylic amine (R1) was essential for Ca(2+) influx inhibition and that the S-configuration was better than the R-configuration. The derivatives in which the right-side R3 was substituted by an electron-donating group showed more potent inhibitory activity than those that were substituted by electron-withdrawing groups. Furthermore, the free N-H of urea was not necessary to maintain the high potency of Ca(2+) influx inhibition. The N,N'-disubstituted or N'-substituted derivatives showed relatively low cytotoxicity but maintained the ability to inhibit IL-2 production. Among them, compound 5b showed an improved inhibition of IL-2 production and low cytotoxicity. CONCLUSION 1-Phenyl-3-(1-phenylethyl)urea is a novel CRAC channel inhibitor that specifically targets ORAI1. This study provides a new chemical scaffold for design and development of CRAC channel inhibitors with improved Ca(2+) influx inhibition, immune inhibition and low cytotoxicity.
Collapse
|
19
|
Yamashita M, Prakriya M. Divergence of Ca(2+) selectivity and equilibrium Ca(2+) blockade in a Ca(2+) release-activated Ca(2+) channel. ACTA ACUST UNITED AC 2014; 143:325-43. [PMID: 24567508 PMCID: PMC3933933 DOI: 10.1085/jgp.201311108] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The Ca2+ selectivity of CRAC channels depends on the kinetics of ion entry and exit as well as the steady-state Ca2+ binding affinity. Prevailing models postulate that high Ca2+ selectivity of Ca2+ release-activated Ca2+ (CRAC) channels arises from tight Ca2+ binding to a high affinity site within the pore, thereby blocking monovalent ion flux. Here, we examined the contribution of high affinity Ca2+ binding for Ca2+ selectivity in recombinant Orai3 channels, which function as highly Ca2+-selective channels when gated by the endoplasmic reticulum Ca2+ sensor STIM1 or as poorly Ca2+-selective channels when activated by the small molecule 2-aminoethoxydiphenyl borate (2-APB). Extracellular Ca2+ blocked Na+ currents in both gating modes with a similar inhibition constant (Ki; ∼25 µM). Thus, equilibrium binding as set by the Ki of Ca2+ blockade cannot explain the differing Ca2+ selectivity of the two gating modes. Unlike STIM1-gated channels, Ca2+ blockade in 2-APB–gated channels depended on the extracellular Na+ concentration and exhibited an anomalously steep voltage dependence, consistent with enhanced Na+ pore occupancy. Moreover, the second-order rate constants of Ca2+ blockade were eightfold faster in 2-APB–gated channels than in STIM1-gated channels. A four-barrier, three–binding site Eyring model indicated that lowering the entry and exit energy barriers for Ca2+ and Na+ to simulate the faster rate constants of 2-APB–gated channels qualitatively reproduces their low Ca2+ selectivity, suggesting that ion entry and exit rates strongly affect Ca2+ selectivity. Noise analysis indicated that the unitary Na+ conductance of 2-APB–gated channels is fourfold larger than that of STIM1-gated channels, but both modes of gating show a high open probability (Po; ∼0.7). The increase in current noise during channel activation was consistent with stepwise recruitment of closed channels to a high Po state in both cases, suggesting that the underlying gating mechanisms are operationally similar in the two gating modes. These results suggest that both high affinity Ca2+ binding and kinetic factors contribute to high Ca2+ selectivity in CRAC channels.
Collapse
Affiliation(s)
- Megumi Yamashita
- Department of Molecular Pharmacology and Biological Chemistry, Northwestern University Feinberg School of Medicine, Chicago, IL 60611
| | | |
Collapse
|
20
|
Signaling pathways activated by a protease allergen in basophils. Proc Natl Acad Sci U S A 2014; 111:E4963-71. [PMID: 25369937 DOI: 10.1073/pnas.1418959111] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Allergic diseases represent a significant burden in industrialized countries, but why and how the immune system responds to allergens remain largely unknown. Because many clinically significant allergens have proteolytic activity, and many helminths express proteases that are necessary for their life cycles, host mechanisms likely have evolved to detect the proteolytic activity of helminth proteases, which may be incidentally activated by protease allergens. A cysteine protease, papain, is a prototypic protease allergen that can directly activate basophils and mast cells, leading to the production of cytokines, including IL-4, characteristic of the type 2 immune response. The mechanism of papain's immunogenic activity remains unknown. Here we have characterized the cellular response activated by papain in basophils. We find that papain-induced IL-4 production requires calcium flux and activation of PI3K and nuclear factor of activated T cells. Interestingly, papain-induced IL-4 production was dependent on the immunoreceptor tyrosine-based activation motif (ITAM) adaptor protein Fc receptor γ-chain, even though the canonical ITAM signaling was not activated by papain. Collectively, these data characterize the downstream signaling pathway activated by a protease allergen in basophils.
Collapse
|
21
|
Petersen O. Can specific calcium channel blockade be the basis for a drug-based treatment of acute pancreatitis? Expert Rev Gastroenterol Hepatol 2014; 8:339-41. [PMID: 24580045 DOI: 10.1586/17474124.2014.896192] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Affiliation(s)
- Ole Petersen
- Cardiff University - Cardiff School of Biosciences, The Sir Martin Evans Building Museum Avenue, Cardiff CF10 3AX, UK
| |
Collapse
|
22
|
Sheridan JT, Gilmore RC, Watson MJ, Archer CB, Tarran R. 17β-Estradiol inhibits phosphorylation of stromal interaction molecule 1 (STIM1) protein: implication for store-operated calcium entry and chronic lung diseases. J Biol Chem 2013; 288:33509-33518. [PMID: 24114840 DOI: 10.1074/jbc.m113.486662] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Sex plays a significant role in the development of lung diseases including asthma, cancer, chronic bronchitis, and cystic fibrosis. In cystic fibrosis, 17β-estradiol (E2) may inhibit store-operated Ca(2+) entry (SOCE) to impinge upon airway secretions, leaving females at greater risk of contracting lung infections. Stromal interaction molecule 1 (STIM1)-mediated SOCE is essential for cell homeostasis and regulates numerous processes including cell proliferation, smooth muscle contraction, and secretion. E2 can signal nongenomically to modulate Ca(2+) signaling, but little is known of the underlying mechanisms. We found that E2 exposure inhibited STIM1 translocation in airway epithelia, preventing SOCE. This correlated with a decrease in STIM1-STIM1 FRET and STIM1 mobility in E2-exposed HEK293T cells co-expressing estrogen receptor α. We also examined the role of STIM1 phosphorylation in E2-mediated inhibition of STIM1 mobility. STIM1 is basally phosphorylated at serine 575, which is required for SOCE. Exposure to E2 significantly decreased STIM1 serine phosphorylation. Mutating serine 575 to an alanine blocked STIM1 phosphorylation, reduced basal STIM1 mobility, and rendered STIM1 insensitive to E2. These data indicate that E2 can signal nongenomically by inhibiting basal phosphorylation of STIM1, leading to a reduction in SOCE.
Collapse
Affiliation(s)
- John T Sheridan
- Department of Cell and Molecular Physiology, the University of North Carolina, Chapel Hill, North Carolina 27599
| | - Rodney C Gilmore
- Cystic Fibrosis/Pulmonary Research and Treatment Center, the University of North Carolina, Chapel Hill, North Carolina 27599
| | - Michael J Watson
- Cystic Fibrosis/Pulmonary Research and Treatment Center, the University of North Carolina, Chapel Hill, North Carolina 27599
| | - Christopher B Archer
- Cystic Fibrosis/Pulmonary Research and Treatment Center, the University of North Carolina, Chapel Hill, North Carolina 27599
| | - Robert Tarran
- Department of Cell and Molecular Physiology, the University of North Carolina, Chapel Hill, North Carolina 27599; Cystic Fibrosis/Pulmonary Research and Treatment Center, the University of North Carolina, Chapel Hill, North Carolina 27599.
| |
Collapse
|
23
|
Kaur R, Sloan LA, Blanchard AD, Smith JL, Churcher I, Wayne GJ, Ludbrook SB. A Phenotypic Screening Approach in Cord Blood–Derived Mast Cells to Identify Anti-Inflammatory Compounds. ACTA ACUST UNITED AC 2013; 18:1223-33. [DOI: 10.1177/1087057113500073] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Mast cells are unique hematopoietic cells that are richly distributed in the skin and mucosal surfaces of the respiratory and gastrointestinal tract. They play a key role in allergic inflammation by releasing a cocktail of granular constituents, including histamine, serine proteases, and various eicosanoids and cytokines. As such, a number of drugs target either inhibition of mast cell degranulation or the products of degranulation. To identify potential novel drugs and mechanisms in mast cell biology, assays were developed to identify inhibitors of mast cell degranulation and activation in a phenotypic screen. Due to the challenges associated with obtaining primary mast cells, cord blood–derived mononuclear cells were reproducibly differentiated to mast cells and assays developed to monitor tryptase release and prostaglandin D2 generation. The tryptase assay was particularly sensitive, requiring only 500 cells per data point, which permitted a set of approximately 12,000 compounds to be screened robustly and cost-effectively. Active compounds were tested for concomitant inhibition of prostaglandin D2 generation. This study demonstrates the robustness and effectiveness of this approach in the identification of potential novel compounds and mechanisms targeting mast cell–driven inflammation, to enable innovative drug discovery efforts to be prosecuted.
Collapse
Affiliation(s)
- Rejbinder Kaur
- GlaxoSmithKline Medicines Research Centre, Stevenage, Hertfordshire, UK
| | - Lisa A. Sloan
- GlaxoSmithKline Medicines Research Centre, Stevenage, Hertfordshire, UK
| | - Andy D. Blanchard
- GlaxoSmithKline Medicines Research Centre, Stevenage, Hertfordshire, UK
| | - Janet L. Smith
- GlaxoSmithKline Medicines Research Centre, Stevenage, Hertfordshire, UK
| | - Ian Churcher
- GlaxoSmithKline Medicines Research Centre, Stevenage, Hertfordshire, UK
| | - Gareth J. Wayne
- GlaxoSmithKline Medicines Research Centre, Stevenage, Hertfordshire, UK
| | | |
Collapse
|
24
|
Abstract
Acute pancreatitis is a human disease in which the pancreatic pro-enzymes, packaged into the zymogen granules of acinar cells, become activated and cause autodigestion. The main causes of pancreatitis are alcohol abuse and biliary disease. A considerable body of evidence indicates that the primary event initiating the disease process is the excessive release of Ca(2+) from intracellular stores, followed by excessive entry of Ca(2+) from the interstitial fluid. However, Ca(2+) release and subsequent entry are also precisely the processes that control the physiological secretion of digestive enzymes in response to stimulation via the vagal nerve or the hormone cholecystokinin. The spatial and temporal Ca(2+) signal patterns in physiology and pathology, as well as the contributions from different organelles in the different situations, are therefore critical issues. There has recently been significant progress in our understanding of both physiological stimulus-secretion coupling and the pathophysiology of acute pancreatitis. Very recently, a promising potential therapeutic development has occurred with the demonstration that the blockade of Ca(2+) release-activated Ca(2+) currents in pancreatic acinar cells offers remarkable protection against Ca(2+) overload, intracellular protease activation and necrosis evoked by a combination of alcohol and fatty acids, which is a major trigger of acute pancreatitis.
Collapse
Affiliation(s)
- Julia V Gerasimenko
- MRC Group, School of Biosciences, Cardiff University, The Sir Martin Evans Building, Museum Avenue, Cardiff CF10 3AX, UK.
| | | | | |
Collapse
|
25
|
Ca2+ release-activated Ca2+ channel blockade as a potential tool in antipancreatitis therapy. Proc Natl Acad Sci U S A 2013; 110:13186-91. [PMID: 23878235 DOI: 10.1073/pnas.1300910110] [Citation(s) in RCA: 137] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Alcohol-related acute pancreatitis can be mediated by a combination of alcohol and fatty acids (fatty acid ethyl esters) and is initiated by a sustained elevation of the Ca(2+) concentration inside pancreatic acinar cells ([Ca(2+)]i), due to excessive release of Ca(2+) stored inside the cells followed by Ca(2+) entry from the interstitial fluid. The sustained [Ca(2+)]i elevation activates intracellular digestive proenzymes resulting in necrosis and inflammation. We tested the hypothesis that pharmacological blockade of store-operated or Ca(2+) release-activated Ca(2+) channels (CRAC) would prevent sustained elevation of [Ca(2+)]i and therefore protease activation and necrosis. In isolated mouse pancreatic acinar cells, CRAC channels were activated by blocking Ca(2+) ATPase pumps in the endoplasmic reticulum with thapsigargin in the absence of external Ca(2+). Ca(2+) entry then occurred upon admission of Ca(2+) to the extracellular solution. The CRAC channel blocker developed by GlaxoSmithKline, GSK-7975A, inhibited store-operated Ca(2+) entry in a concentration-dependent manner within the range of 1 to 50 μM (IC50 = 3.4 μM), but had little or no effect on the physiological Ca(2+) spiking evoked by acetylcholine or cholecystokinin. Palmitoleic acid ethyl ester (100 μM), an important mediator of alcohol-related pancreatitis, evoked a sustained elevation of [Ca(2+)]i, which was markedly reduced by CRAC blockade. Importantly, the palmitoleic acid ethyl ester-induced trypsin and protease activity as well as necrosis were almost abolished by blocking CRAC channels. There is currently no specific treatment of pancreatitis, but our data show that pharmacological CRAC blockade is highly effective against toxic [Ca(2+)]i elevation, necrosis, and trypsin/protease activity and therefore has potential to effectively treat pancreatitis.
Collapse
|
26
|
Velema WA, van der Toorn M, Szymanski W, Feringa BL. Design, Synthesis, and Inhibitory Activity of Potent, Photoswitchable Mast Cell Activation Inhibitors. J Med Chem 2013; 56:4456-64. [DOI: 10.1021/jm400115k] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- Willem A. Velema
- Centre for Systems Chemistry,
Stratingh Institute for Chemistry, University of Groningen, Nijenborgh
4, 9747 AG Groningen, The Netherlands
| | - Marco van der Toorn
- Laboratory of Allergology and
Pulmonary Diseases, Department of Pathology and Medical Biology, University
Medical Centre Groningen, 9713 GZ Groningen, The Netherlands
| | - Wiktor Szymanski
- Centre for Systems Chemistry,
Stratingh Institute for Chemistry, University of Groningen, Nijenborgh
4, 9747 AG Groningen, The Netherlands
| | - Ben L. Feringa
- Centre for Systems Chemistry,
Stratingh Institute for Chemistry, University of Groningen, Nijenborgh
4, 9747 AG Groningen, The Netherlands
| |
Collapse
|
27
|
McNally BA, Somasundaram A, Jairaman A, Yamashita M, Prakriya M. The C- and N-terminal STIM1 binding sites on Orai1 are required for both trapping and gating CRAC channels. J Physiol 2013; 591:2833-50. [PMID: 23613525 DOI: 10.1113/jphysiol.2012.250456] [Citation(s) in RCA: 101] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Ca(2+) release-activated Ca(2+) (CRAC) channels are activated through a mechanism wherein depletion of intracellular calcium stores results in the aggregation of stromal interaction molecule 1 (STIM1), the endoplasmic reticulum (ER) Ca(2+) sensor, and Orai1, the CRAC channel protein, at overlapping sites in the ER and plasma membranes (PMs). The redistribution of CRAC channels is driven through direct STIM1-Orai1 binding, an important event that not only controls gating, but also regulates Orai1 ion selectivity. Orai1 harbours two STIM1 binding sites, one each on the intracellular C- and N-termini. Previous studies have proposed modular functions for these sites, with the C-terminal site thought to regulate STIM1-Orai1 binding and trapping of Orai1 at the ER-PM junctions, and the N-terminal site mediating gating. However, here we find that a variety of mutations in the N-terminal site impair the binding of Orai1 to STIM1 and to the soluble CRAC activation domain (CAD). Gating could be restored in several N- and C-terminal point mutants by directly tethering the minimal STIM1 activation domain (S) to Orai1 (Orai1-SS channels), indicating that loss of gating in these mutants by full-length STIM1 results from insufficient ligand binding. By contrast, gating could not be restored in mutant Orai1-SS channels carrying more drastic deletions that removed the STIM1 binding sites (1-85, 73-85, or 272-279 Orai1), suggesting that STIM1 binding to both sites is essential for channel activation. Moreover, analysis of ion selectivity indicated that the molecular requirements for gating and modulation of ion selectivity are similar, yet substantively different from those for Orai1 puncta formation, suggesting that ion selectivity and gating are mechanistically coupled in CRAC channels. Our results indicate that the C- and N-terminal STIM1 binding sites are both essential for multiple aspects of Orai1 function including STIM1-Orai1 association, Orai1 trapping, and channel activation.
Collapse
Affiliation(s)
- Beth A McNally
- Department of Molecular Pharmacology and Biological Chemistry, Northwestern University School of Medicine, 303 E Chicago Avenue, Ward 8-296, Chicago, IL 60611, USA
| | | | | | | | | |
Collapse
|
28
|
Bergmeier W, Weidinger C, Zee I, Feske S. Emerging roles of store-operated Ca²⁺ entry through STIM and ORAI proteins in immunity, hemostasis and cancer. Channels (Austin) 2013; 7:379-91. [PMID: 23511024 DOI: 10.4161/chan.24302] [Citation(s) in RCA: 90] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Store-operated Ca(2+) entry (SOCE) is an important Ca(2+) influx pathway, which is defined by the fact that depletion of intracellular Ca(2+) stores, mainly the endoplasmic reticulum (ER), triggers the opening of Ca(2+) channels in the plasma membrane. The best characterized SOC channel is the Ca(2+) release-activated Ca(2+) (CRAC) channel, which was first described in cells of the immune system but has since been reported in many different cell types. CRAC channels are multimers of ORAI family proteins, of which ORAI1 is the best characterized. They are activated by stromal interaction molecules (STIM) 1 and 2, which respond to the depletion of intracellular Ca(2+) stores with oligomerization and binding to ORAI proteins. The resulting SOCE is critical for the physiological function of many cell types including immune cells and platelets. Recent studies using cell lines, animal models and primary cells from human patients with defects in SOCE have highlighted the importance of this Ca(2+) entry mechanism in a variety of pathophysiological processes. This review focuses on the role of SOCE in immunity to infection, allergy, hemostasis and cancer.
Collapse
Affiliation(s)
- Wolfgang Bergmeier
- Department of Biochemistry and Biophysics; McAllister Heart Institute; University of North Carolina; Chapel Hill, NC USA
| | - Carl Weidinger
- Department of Pathology; New York University Langone Medical Center; New York, NY USA
| | - Isabelle Zee
- Department of Pathology; New York University Langone Medical Center; New York, NY USA
| | - Stefan Feske
- Department of Pathology; New York University Langone Medical Center; New York, NY USA
| |
Collapse
|
29
|
Medic N, Desai A, Olivera A, Abramowitz J, Birnbaumer L, Beaven MA, Gilfillan AM, Metcalfe DD. Knockout of the Trpc1 gene reveals that TRPC1 can promote recovery from anaphylaxis by negatively regulating mast cell TNF-α production. Cell Calcium 2013; 53:315-26. [PMID: 23489970 DOI: 10.1016/j.ceca.2013.02.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2012] [Revised: 01/10/2013] [Accepted: 02/07/2013] [Indexed: 11/28/2022]
Abstract
Antigen-mediated mast cell (MC) degranulation is the critical early event in the induction of allergic reactions. Transient receptor potential channels (TRPC), particularly TRPC1, are thought to contribute to such MC activation. To explore the contribution of TRPC1 in MC-driven allergic reactions, we examined antigen-mediated anaphylaxis in Trpc1⁻/⁻ and WT mice, and TRPC1 involvement in the activation of MCs derived from the bone marrow (BMMCs) of these mice. In vivo, we observed a similar induction of passive systemic anaphylaxis in the Trpc1⁻/⁻ mice compared to WT controls. Nevertheless, there was delayed recovery from this response in Trpc1⁻/⁻ mice. Furthermore, contrary to expectations, Trpc1⁻/⁻ BMMCs responded to antigen with enhanced calcium signaling but with little defect in degranulation or associated signaling. In contrast, antigen-mediated production of TNF-α, and other cytokines, was enhanced in the Trpc1⁻/⁻ BMMCs, as were calcium-dependent events required for these responses. Additionally, circulating levels of TNF-α in response to antigen were preferentially elevated in the Trpc1⁻/⁻ mice, and administration of an anti-TNF-α antibody blocked the delay in recovery from anaphylaxis in these mice. These data thus provide evidence that, in this model, TRPC1 promotes recovery from the anaphylactic response by repressing antigen-mediated TNF-α release from MCs.
Collapse
Affiliation(s)
- Nevenka Medic
- Laboratory of Allergic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 10 Center Drive MSC 1881, Bethesda, MD 20892-1881, USA
| | | | | | | | | | | | | | | |
Collapse
|
30
|
Abstract
In many animal cells, store-operated Ca(2+) release-activated Ca(2+) (CRAC) channels function as an essential route for Ca(2+) entry. CRAC channels control many fundamental cellular functions including gene expression, motility, and cell proliferation, are involved in the etiology of several disease processes including a severe combined immunodeficiency syndrome, and have emerged as major targets for drug development. Although little was known of the molecular mechanisms of CRAC channel operation for several decades, the discovery of Orai1 as a prototypic CRAC channel protein and STIM1 as the endoplasmic reticulum (ER) Ca(2+) sensor has led to rapid progress in our understanding of the mechanisms and functions of CRAC channels. It is now known that activation of CRAC channels following ER Ca(2+) store depletion is governed by several events, which include the redistributions and accumulations of STIM1 and Orai1 into overlapping puncta at peripheral cellular sites, resulting in direct protein-protein interactions between the two proteins. In this chapter, I review the molecular features of the STIM and Orai proteins that regulate the gating and ion conduction mechanisms of CRAC channels.
Collapse
Affiliation(s)
- Murali Prakriya
- Department of Molecular Pharmacology and Biological Chemistry, Northwestern University, Feinberg School of Medicine, Chicago, Illinois, USA.
| |
Collapse
|
31
|
Mitochondrial function and malfunction in the pathophysiology of pancreatitis. Pflugers Arch 2012; 464:89-99. [PMID: 22653502 DOI: 10.1007/s00424-012-1117-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2012] [Revised: 05/11/2012] [Accepted: 05/15/2012] [Indexed: 12/13/2022]
Abstract
As a primary energy producer, mitochondria play a fundamental role in pancreatic exocrine physiology and pathology. The most frequent aetiology of acute pancreatitis is either gallstones or heavy alcohol consumption. Repeated episodes of acute pancreatitis can result in the development of chronic pancreatitis and increase the lifetime risk of pancreatic cancer 100-fold. Pancreatic cancer is one of the most common causes of cancer mortality with only about 3-4 % of patients surviving beyond 5 years. It has been shown that acute pancreatitis involves Ca²⁺ overload and overproduction of reactive oxygen species in pancreatic acinar cells. Both factors significantly affect mitochondria and lead to cell death. The pathogenesis of inflammation in acute and chronic pancreatitis is tightly linked to the induction of necrosis and apoptosis. There is currently no specific therapy for pancreatitis, but recent findings of an endogenous protective mechanism against Ca²⁺ overload--and particularly the potential to boost this protection--bring hope of new therapeutic approaches.
Collapse
|
32
|
Holowka D, Calloway N, Cohen R, Gadi D, Lee J, Smith NL, Baird B. Roles for ca(2+) mobilization and its regulation in mast cell functions. Front Immunol 2012; 3:104. [PMID: 22586429 PMCID: PMC3346949 DOI: 10.3389/fimmu.2012.00104] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2011] [Accepted: 04/16/2012] [Indexed: 01/08/2023] Open
Abstract
Mobilization of Ca2+ in response to IgE receptor-mediated signaling is a key process in many aspects of mast cell function. Here we summarize our current understanding of the molecular bases for this process and the roles that it plays in physiologically relevant mast cell biology. Activation of IgE receptor signaling by antigen that crosslinks these complexes initiates Ca2+ mobilization as a fast wave that is frequently followed by a series of Ca2+ oscillations which are dependent on Ca2+ influx-mediated by coupling of the endoplasmic reticulum luminal Ca2+ sensor STIM1 to the calcium release activated calcium channel protein Orai1. Granule exocytosis depends on this process, together with the activation of protein kinase C isoforms, and specific roles for these signaling steps are beginning to be understood. Ca2+ mobilization also plays important roles in stimulated exocytosis of recycling endosomes and newly synthesized cytokines, as well as in antigen-mediated chemotaxis of rat mucosal mast cells. Phosphoinositide metabolism plays key roles in all of these processes, and we highlight these roles in several cases.
Collapse
Affiliation(s)
- David Holowka
- Department of Chemistry and Chemical Biology, Cornell University Ithaca, NY, USA
| | | | | | | | | | | | | |
Collapse
|
33
|
Gerasimenko OV, Petersen OH, Gerasimenko JV. Role of intracellular acid Ca(2+) stores in pathological pancreatic protease activation. Expert Rev Gastroenterol Hepatol 2012; 6:129-31. [PMID: 22375516 DOI: 10.1586/egh.12.5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
34
|
Calcium Signaling in Mast Cells: Focusing on L-Type Calcium Channels. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 740:955-77. [DOI: 10.1007/978-94-007-2888-2_44] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
35
|
Petersen OH, Gerasimenko OV, Gerasimenko JV. Pathobiology of acute pancreatitis: focus on intracellular calcium and calmodulin. F1000 MEDICINE REPORTS 2011; 3:15. [PMID: 21876721 PMCID: PMC3155209 DOI: 10.3410/m3-15] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The exocrine pancreas synthesizes all the enzymes needed for intestinal breakdown of proteins, fats, and carbohydrates in our diet. Unfortunately, the proteases needed for the digestion of the meat we eat can, if inappropriately activated inside the acinar cells, also digest the pancreas itself as well as the surrounding tissues, which is what happens in the sometimes fatal human disease acute pancreatitis. The disease is currently untreatable, but significant progress has recently been made in understanding the fundamental processes initiating the pathological changes underlying pancreatic autodigestion. It is now clear that intracellular trypsin activation—a crucial step in pathogenesis—is due to excessive release of Ca2+ from intracellular stores, principally via two types of inositol trisphosphate receptor. The unexpected recent discovery of an intrinsic protective mechanism caused by intracellular calmodulin and, specifically, the finding that this protective effect can be boosted by a membrane-permeable Ca2+-like peptide are promising.
Collapse
Affiliation(s)
- Ole H Petersen
- MRC Group, Cardiff School of Biosciences, Cardiff University Biomedical Sciences Building, Museum Avenue, Cardiff, CF10 3AX UK
| | | | | |
Collapse
|
36
|
Abstract
Mast cells are multifunctional cells that initiate not only IgE-dependent allergic diseases but also play a fundamental role in innate and adaptive immune responses to microbial infection. They are also thought to play a role in angiogenesis, tissue remodeling, wound healing, and tumor repression or growth. The broad scope of these physiologic and pathologic roles illustrates the flexible nature of mast cells, which is enabled in part by their phenotypic adaptability to different tissue microenvironments and their ability to generate and release a diverse array of bioactive mediators in response to multiple types of cell-surface and cytosolic receptors. There is increasing evidence from studies in cell cultures that release of these mediators can be selectively modulated depending on the types or groups of receptors activated. The intent of this review is to foster interest in the interplay among mast cell receptors to help understand the underlying mechanisms for each of the immunological and non-immunological functions attributed to mast cells. The second intent of this review is to assess the pathophysiologic roles of mast cells and their products in health and disease. Although mast cells have a sufficient repertoire of bioactive mediators to mount effective innate and adaptive defense mechanisms against invading microorganisms, these same mediators can adversely affect surrounding tissues in the host, resulting in autoimmune disease as well as allergic disorders.
Collapse
Affiliation(s)
- Alasdair M Gilfillan
- Laboratory of Allergic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892-1881, USA.
| | | |
Collapse
|