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Gerasimovskaya E, Patil RS, Davies A, Maloney ME, Simon L, Mohamed B, Cherian-Shaw M, Verin AD. Extracellular purines in lung endothelial permeability and pulmonary diseases. Front Physiol 2024; 15:1450673. [PMID: 39234309 PMCID: PMC11372795 DOI: 10.3389/fphys.2024.1450673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2024] [Accepted: 08/05/2024] [Indexed: 09/06/2024] Open
Abstract
The purinergic signaling system is an evolutionarily conserved and critical regulatory circuit that maintains homeostatic balance across various organ systems and cell types by providing compensatory responses to diverse pathologies. Despite cardiovascular diseases taking a leading position in human morbidity and mortality worldwide, pulmonary diseases represent significant health concerns as well. The endothelium of both pulmonary and systemic circulation (bronchial vessels) plays a pivotal role in maintaining lung tissue homeostasis by providing an active barrier and modulating adhesion and infiltration of inflammatory cells. However, investigations into purinergic regulation of lung endothelium have remained limited, despite widespread recognition of the role of extracellular nucleotides and adenosine in hypoxic, inflammatory, and immune responses within the pulmonary microenvironment. In this review, we provide an overview of the basic aspects of purinergic signaling in vascular endothelium and highlight recent studies focusing on pulmonary microvascular endothelial cells and endothelial cells from the pulmonary artery vasa vasorum. Through this compilation of research findings, we aim to shed light on the emerging insights into the purinergic modulation of pulmonary endothelial function and its implications for lung health and disease.
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Affiliation(s)
| | - Rahul S Patil
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA, United States
| | - Adrian Davies
- Department of Internal Medicine, Medical College of Georgia, Augusta University, Augusta, GA, United States
| | - McKenzie E Maloney
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA, United States
- Office of Academic Affairs, Medical College of Georgia, Augusta University, Augusta, GA, United States
| | - Liselle Simon
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA, United States
| | - Basmah Mohamed
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA, United States
| | - Mary Cherian-Shaw
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA, United States
| | - Alexander D Verin
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA, United States
- Department of Medicine, Medical College of Georgia, Augusta University, Augusta, GA, United States
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2
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Effah F, Elzein A, Taiwo B, Baines D, Bailey A, Marczylo T. In Vitro high-throughput toxicological assessment of E-cigarette flavors on human bronchial epithelial cells and the potential involvement of TRPA1 in cinnamon flavor-induced toxicity. Toxicology 2023; 496:153617. [PMID: 37595738 DOI: 10.1016/j.tox.2023.153617] [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: 04/27/2023] [Revised: 08/06/2023] [Accepted: 08/15/2023] [Indexed: 08/20/2023]
Abstract
Electronic cigarettes (ECs) are considered a less hazardous alternative to tobacco smoking but are not harmless. Growing concerns about the safety profiles of flavors in e-liquids underpin the need for this study. Here, we screened 53 nicotine-free flavored e-liquids (across 15 flavor categories) across a 3-point concentration range (0.25%, 0.5%, and 1% v/v) in a high-throughput fashion in human bronchial epithelial (HBEC-3KT) submerged cell cultures to identify 'toxic hits' using in vitro endpoint assays comprising cell count, cell viability, and lactate dehydrogenase (LDH). We observed significant, dose-dependent adverse effects only with cinnamon, vanilla tobacco, and hazelnut e-liquids compared to media-only and PG/VG vehicle controls. Hence, we further analyzed these three flavors for their effects on HBEC-3KT proliferation, mitochondrial health, and oxidative stress. A significant decrease in cell proliferation after 36 h was observed for each e-liquid toxic hit compared to media-only and PG/VG controls. Hazelnut (at all concentrations) and vanilla tobacco (1%) increased cytoplasmic reactive oxygen species generation compared to media-only and PG/VG controls. Conversely, all three flavors at 0.5% and 1% significantly decreased mitochondrial membrane potential compared to PG/VG and media-only controls. Chemical analysis revealed that all three flavors contained volatile organic compounds. We hypothesized that the cytotoxicity of cinnamon might be mediated via TRPA1; however, TRPA1 antagonist AP-18 (10 μM) did not mitigate these effects, and cinnamon significantly increased TRPA1 transcript levels. Therefore, pathways mediating cinnamon's cytotoxicity warrant further investigations. This study could inform public health authorities on the relative health risks assessment following exposure to EC flavor ingredients.
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Affiliation(s)
- Felix Effah
- Pharmacology Section, St George's University of London, Cranmer Terrace, SW17 0RE London, UK; UK Health Security Agency, Radiation, Chemical and Environmental Hazards, Chilton, Didcot, Oxfordshire OX11 ORQ, UK.
| | - Atallah Elzein
- UK Health Security Agency, Radiation, Chemical and Environmental Hazards, Chilton, Didcot, Oxfordshire OX11 ORQ, UK
| | - Benjamin Taiwo
- Physiology Section, St George's University of London, Cranmer Terrace, SW17 0RE London, UK
| | - Deborah Baines
- Infection and Immunity Institute, St George's University of London, Cranmer Terrace, SW17 0RE London, UK
| | - Alexis Bailey
- Pharmacology Section, St George's University of London, Cranmer Terrace, SW17 0RE London, UK
| | - Tim Marczylo
- UK Health Security Agency, Radiation, Chemical and Environmental Hazards, Chilton, Didcot, Oxfordshire OX11 ORQ, UK.
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3
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Ley-Ngardigal S, Bertolin G. Approaches to monitor ATP levels in living cells: where do we stand? FEBS J 2022; 289:7940-7969. [PMID: 34437768 DOI: 10.1111/febs.16169] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 07/30/2021] [Accepted: 08/25/2021] [Indexed: 01/14/2023]
Abstract
ATP is the most universal and essential energy molecule in cells. This is due to its ability to store cellular energy in form of high-energy phosphate bonds, which are extremely stable and readily usable by the cell. This energy is key for a variety of biological functions such as cell growth and division, metabolism, and signaling, and for the turnover of biomolecules. Understanding how ATP is produced and hydrolyzed with a spatiotemporal resolution is necessary to understand its functions both in physiological and in pathological contexts. In this review, first we will describe the organization of the electron transport chain and ATP synthase, the main molecular motor for ATP production in mitochondria. Second, we will review the biochemical assays currently available to estimate ATP quantities in cells, and we will compare their readouts, strengths, and weaknesses. Finally, we will explore the palette of genetically encoded biosensors designed for microscopy-based approaches, and show how their spatiotemporal resolution opened up the possibility to follow ATP levels in living cells.
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Affiliation(s)
- Seyta Ley-Ngardigal
- CNRS, Univ Rennes, IGDR (Genetics and Development Institute of Rennes), Rennes, France.,LVMH Research Perfumes and Cosmetics, Saint-Jean-de-Braye, France
| | - Giulia Bertolin
- CNRS, Univ Rennes, IGDR (Genetics and Development Institute of Rennes), Rennes, France
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4
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Jamison DA, Anand Narayanan S, Trovão NS, Guarnieri JW, Topper MJ, Moraes-Vieira PM, Zaksas V, Singh KK, Wurtele ES, Beheshti A. A comprehensive SARS-CoV-2 and COVID-19 review, Part 1: Intracellular overdrive for SARS-CoV-2 infection. Eur J Hum Genet 2022; 30:889-898. [PMID: 35577935 PMCID: PMC9108708 DOI: 10.1038/s41431-022-01108-8] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 03/20/2022] [Accepted: 04/12/2022] [Indexed: 12/15/2022] Open
Abstract
COVID-19, the disease caused by SARS-CoV-2, has claimed approximately 5 million lives and 257 million cases reported globally. This virus and disease have significantly affected people worldwide, whether directly and/or indirectly, with a virulent pathogen that continues to evolve as we race to learn how to prevent, control, or cure COVID-19. The focus of this review is on the SARS-CoV-2 virus' mechanism of infection and its proclivity at adapting and restructuring the intracellular environment to support viral replication. We highlight current knowledge and how scientific communities with expertize in viral, cellular, and clinical biology have contributed to increase our understanding of SARS-CoV-2, and how these findings may help explain the widely varied clinical observations of COVID-19 patients.
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Affiliation(s)
| | - S Anand Narayanan
- COVID-19 International Research Team, Medford, MA, USA.
- Department of Nutrition & Integrative Physiology, Florida State University, Tallahassee, FL, USA.
| | - Nídia S Trovão
- COVID-19 International Research Team, Medford, MA, USA
- Fogarty International Center, National Institutes of Health, Bethesda, MD, USA
| | - Joseph W Guarnieri
- COVID-19 International Research Team, Medford, MA, USA
- Center for Mitochondrial and Epigenomic Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Michael J Topper
- COVID-19 International Research Team, Medford, MA, USA
- Department of Oncology, The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD, USA
| | - Pedro M Moraes-Vieira
- COVID-19 International Research Team, Medford, MA, USA
- Department of Genetics, Evolution, Microbiology and Immunology, Institute of Biology, University of Campinas, Campinas, SP, Brazil
- Obesity and Comorbidities research Center (OCRC), University of Campinas, Campinas, SP, Brazil
- Experimental Medicine Research Cluster, University of Campinas, Campinas, Brazil
| | - Viktorija Zaksas
- COVID-19 International Research Team, Medford, MA, USA
- Center for Translational Data Science, University of Chicago, Chicago, IL, USA
| | - Keshav K Singh
- COVID-19 International Research Team, Medford, MA, USA
- Department of Genetics, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Eve Syrkin Wurtele
- COVID-19 International Research Team, Medford, MA, USA
- Center for Metabolic Biology, Bioinformatics and Computational Biology, and Genetics Development, and Cell Biology, Iowa State University, Ames, IA, USA
| | - Afshin Beheshti
- COVID-19 International Research Team, Medford, MA, USA.
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA, USA.
- KBR, Space Biosciences Division, NASA Ames Research Center, Moffett Field, CA, USA.
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5
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Manzoor S, Khalid M, Idrees M. P2X4 receptors mediate induction of antioxidants, fibrogenic cytokines and ECM transcripts; in presence of replicating HCV in in vitro setting: An insight into role of P2X4 in fibrosis. PLoS One 2022; 17:e0259727. [PMID: 35594248 PMCID: PMC9122194 DOI: 10.1371/journal.pone.0259727] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Accepted: 03/02/2022] [Indexed: 11/19/2022] Open
Abstract
Background & aims
Major HCV infections lead to chronic hepatitis, which results in progressive liver disease including fibrosis, cirrhosis and eventually hepatocellular carcinoma (HCC). P2X4 and P2X7 are most widely distributed receptors on hepatocytes.
Methods
Full length P2X4 (1.7kb) (Rattus norvegicus) was sub cloned in mammalian expression vector pcDNA3.1+. Two stable cell lines 293T/P2X4 (experimental) and 293T/ NV or null vector (control) were established. Both cell lines were inoculated with high viral titers human HCV sera and control human sera. Successfully infected cells harvested on day 5 and day 9 of post infection were used for further studies.
Results
The results revealed a significant increase in gene expression of P2X4 on day 5 and day 9 Post -infection in cells infected with HCV sera compared with cells inoculated with control sera. Quantitative real time PCR analysis revealed that HO-1 was significantly upregulated in presence of P2X4 in HCV infected cells (P2X4/HCV) when compared with control NV/HCV cells. A significant decrease was observed in expression of Cu/ZnSOD in presence of P2X4 in HCV infected cells compared to control NV/HCV cells. However, expression of both antioxidants was observed unaltered in cells harvested on day 9 post infection. Gene expression of angiotensin II significantly increased in HCV infected cells in presence of P2X4 on day 5 and day 9 of post infection when compared with control NV/HCV cells. A significant increase in gene expression of TNF-α and TGF-β was observed in HCV infected cells in presence of P2X4 on day 9 post infection in comparison with control (NV/HCV cells). However, gene expression of adipokine leptin was not affected in both experimental (P2X4/HCV) and control (NV/HCV) groups on day 5 and day 9 of post infection. Extracellular matrix proteins, laminin and elastin genes expression also significantly increased in presence of P2X4 (HCV/P2X4) on day 9 of post-infection compared to control group NV/HCV cells.
Conclusion
In conclusion, these findings constitute the evidence that P2X4 receptors in the presence of HCV play a significant role in the regulation of key antioxidant enzymes (HO-1, Cu/ZnSOD), in the induction of proinflammatory. cytokine (TNF-α), profibrotic cytokine (TGF-β) vasoactive cytokine (angiotensin II). P2X4 also increases the expression of extracellular matrix proteins (laminin and elastin) in the presence of HCV.
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Affiliation(s)
- Sobia Manzoor
- Center of Excellence in Molecular Biology (CEMB), University of Punjab, Lahore, Pakistan
- Atta-ur-Rahman School of Applied Biosciences (ASAB), National University of Science and Technology (NUST), Islamabad, Pakistan
- * E-mail: ,
| | - Madiha Khalid
- Atta-ur-Rahman School of Applied Biosciences (ASAB), National University of Science and Technology (NUST), Islamabad, Pakistan
| | - Muhammad Idrees
- Center of Excellence in Molecular Biology (CEMB), University of Punjab, Lahore, Pakistan
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6
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Rao R, Shah S, Bhattacharya D, Toukam DK, Cáceres R, Pomeranz Krummel DA, Sengupta S. Ligand-Gated Ion Channels as Targets for Treatment and Management of Cancers. Front Physiol 2022; 13:839437. [PMID: 35350689 PMCID: PMC8957973 DOI: 10.3389/fphys.2022.839437] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 02/07/2022] [Indexed: 12/24/2022] Open
Abstract
Ligand-gated ion channels are an ionotropic receptor subtype characterized by the binding of an extracellular ligand, followed by the transient passage of ions through a transmembrane pore. Ligand-gated ion channels are commonly subcategorized into three superfamilies: purinoreceptors, glutamate receptors, and Cys-loop receptors. This classification is based on the differing topographical morphology of the receptors, which in turn confers functional differences. Ligand-gated ion channels have a diverse spatial and temporal expression which implicate them in key cellular processes. Given that the transcellular electrochemical gradient is finely tuned in eukaryotic cells, any disruption in this homeostasis can contribute to aberrancies, including altering the activity of pro-tumorigenic molecular pathways, such as the MAPK/ERK, RAS, and mTOR pathways. Ligand-gated ion channels therefore serve as a potential targetable system for cancer therapeutics. In this review, we analyze the role that each of the three ligand-gated ion channel superfamilies has concerning tumor proliferation and as a target for the treatment of cancer symptomatology.
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Affiliation(s)
| | | | | | | | | | - Daniel A. Pomeranz Krummel
- Department of Neurology and Rehabilitation Medicine, University of Cincinnati, Cincinnati, OH, United States
| | - Soma Sengupta
- Department of Neurology and Rehabilitation Medicine, University of Cincinnati, Cincinnati, OH, United States
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7
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Fabian KP, Wolfson B, Hodge JW. From Immunogenic Cell Death to Immunogenic Modulation: Select Chemotherapy Regimens Induce a Spectrum of Immune-Enhancing Activities in the Tumor Microenvironment. Front Oncol 2021; 11:728018. [PMID: 34497771 PMCID: PMC8419351 DOI: 10.3389/fonc.2021.728018] [Citation(s) in RCA: 58] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 07/29/2021] [Indexed: 12/22/2022] Open
Abstract
Cancer treatment has rapidly entered the age of immunotherapy, and it is becoming clear that the effective therapy of established tumors necessitates rational multi-combination immunotherapy strategies. But even in the advent of immunotherapy, the clinical role of standard-of-care chemotherapy regimens still remains significant and may be complementary to emerging immunotherapeutic approaches. Depending on dose, schedule, and agent, chemotherapy can induce immunogenic cell death, resulting in the release of tumor antigens to stimulate an immune response, or immunogenic modulation, sensitizing surviving tumor cells to immune cell killing. While these have been previously defined as distinct processes, in this review we examine the published mechanisms supporting both immunogenic cell death and immunogenic modulation and propose they be reclassified as similar effects termed "immunogenic cell stress." Treatment-induced immunogenic cell stress is an important result of cytotoxic chemotherapy and future research should consider immunogenic cell stress as a whole rather than just immunogenic cell death or immunogenic modulation. Cancer treatment strategies should be designed specifically to take advantage of these effects in combination immunotherapy, and novel chemotherapy regimens should be designed and investigated to potentially induce all aspects of immunogenic cell stress.
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Affiliation(s)
| | | | - James W. Hodge
- Laboratory of Tumor Immunology and Biology, Center for Cancer Research, National Cancer Institute, Bethesda, MD, United States
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8
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Drill M, Jones NC, Hunn M, O'Brien TJ, Monif M. Antagonism of the ATP-gated P2X7 receptor: a potential therapeutic strategy for cancer. Purinergic Signal 2021; 17:215-227. [PMID: 33728582 PMCID: PMC8155177 DOI: 10.1007/s11302-021-09776-9] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Accepted: 02/18/2021] [Indexed: 12/19/2022] Open
Abstract
The P2X receptor 7 (P2X7R) is a plasma membrane receptor sensing extracellular ATP associated with a wide variety of cellular functions. It is most commonly expressed on immune cells and is highly upregulated in a number of human cancers where it can play a trophic role in tumorigenesis. Activation of this receptor leads to the formation of a non-selective cation channel, which has been associated with several cellular functions mediated by the PI3K/Akt pathway and protein kinases. Due to its broad range of functions, the receptor represents a potential therapeutic target for a number of cancers. This review describes the range of mechanisms associated with P2X7R activation in cancer settings and highlights the potential of targeted inhibition of P2X7R as a therapy. It also describes in detail a number of key P2X7R antagonists currently in pre-clinical and clinical development, including oxidised ATP, Brilliant Blue G (BBG), KN-62, KN-04, A740003, A438079, GSK1482160, CE-224535, JNJ-54175446, JNJ-55308942, and AZ10606120. Lastly, it summarises the in vivo studies and clinical trials associated with the use and development of these P2X7R antagonists in different disease contexts.
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Affiliation(s)
- Matthew Drill
- Department of Neuroscience, Faculty of Medicine, Nursing and Health Sciences, Central Clinical School, Monash University, Melbourne, VIC, Australia
- Department of Physiology, Melbourne University, Parkville, VIC, Australia
- Department of Neurology, Alfred Health, Melbourne, VIC, Australia
| | - Nigel C Jones
- Department of Neuroscience, Faculty of Medicine, Nursing and Health Sciences, Central Clinical School, Monash University, Melbourne, VIC, Australia
| | - Martin Hunn
- Department of Neuroscience, Faculty of Medicine, Nursing and Health Sciences, Central Clinical School, Monash University, Melbourne, VIC, Australia
- Department of Neurosurgery, Alfred Hospital, Melbourne, VIC, Australia
| | - Terence J O'Brien
- Department of Neuroscience, Faculty of Medicine, Nursing and Health Sciences, Central Clinical School, Monash University, Melbourne, VIC, Australia
- Department of Neurology, Alfred Health, Melbourne, VIC, Australia
| | - Mastura Monif
- Department of Neuroscience, Faculty of Medicine, Nursing and Health Sciences, Central Clinical School, Monash University, Melbourne, VIC, Australia.
- Department of Physiology, Melbourne University, Parkville, VIC, Australia.
- Department of Neurology, Alfred Health, Melbourne, VIC, Australia.
- Department of Neurology, Melbourne Health, Parkville, VIC, Australia.
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9
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Relja B, Land WG. Damage-associated molecular patterns in trauma. Eur J Trauma Emerg Surg 2020; 46:751-775. [PMID: 31612270 PMCID: PMC7427761 DOI: 10.1007/s00068-019-01235-w] [Citation(s) in RCA: 100] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 09/27/2019] [Indexed: 12/13/2022]
Abstract
In 1994, the "danger model" argued that adaptive immune responses are driven rather by molecules released upon tissue damage than by the recognition of "strange" molecules. Thus, an alternative to the "self versus non-self recognition model" has been provided. The model, which suggests that the immune system discriminates dangerous from safe molecules, has established the basis for the future designation of damage-associated molecular patterns (DAMPs), a term that was coined by Walter G. Land, Seong, and Matzinger. The pathological importance of DAMPs is barely somewhere else evident as in the posttraumatic or post-surgical inflammation and regeneration. Since DAMPs have been identified to trigger specific immune responses and inflammation, which is not necessarily detrimental but also regenerative, it still remains difficult to describe their "friend or foe" role in the posttraumatic immunogenicity and healing process. DAMPs can be used as biomarkers to indicate and/or to monitor a disease or injury severity, but they also may serve as clinically applicable parameters for optimized indication of the timing for, i.e., secondary surgeries. While experimental studies allow the detection of these biomarkers on different levels including cellular, tissue, and circulatory milieu, this is not always easily transferable to the human situation. Thus, in this review, we focus on the recent literature dealing with the pathophysiological importance of DAMPs after traumatic injury. Since dysregulated inflammation in traumatized patients always implies disturbed resolution of inflammation, so-called model of suppressing/inhibiting inducible DAMPs (SAMPs) will be very briefly introduced. Thus, an update on this topic in the field of trauma will be provided.
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Affiliation(s)
- Borna Relja
- Experimental Radiology, Department of Radiology and Nuclear Medicine, Otto von Guericke University Magdeburg, Magdeburg, Germany.
- Department of Trauma, Hand and Reconstructive Surgery, University Hospital Frankfurt, Goethe University Frankfurt am Main, 60590, Frankfurt, Germany.
| | - Walter Gottlieb Land
- Molecular ImmunoRheumatology, INSERM UMR_S1109, Laboratory of Excellence Transplantex, University of Strasbourg, Strasbourg, France
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10
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Khalafalla MG, Woods LT, Jasmer KJ, Forti KM, Camden JM, Jensen JL, Limesand KH, Galtung HK, Weisman GA. P2 Receptors as Therapeutic Targets in the Salivary Gland: From Physiology to Dysfunction. Front Pharmacol 2020; 11:222. [PMID: 32231563 PMCID: PMC7082426 DOI: 10.3389/fphar.2020.00222] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Accepted: 02/18/2020] [Indexed: 12/12/2022] Open
Abstract
Although often overlooked in our daily lives, saliva performs a host of necessary physiological functions, including lubricating and protecting the oral cavity, facilitating taste sensation and digestion and maintaining tooth enamel. Therefore, salivary gland dysfunction and hyposalivation, often resulting from pathogenesis of the autoimmune disease Sjögren's syndrome or from radiotherapy of the head and neck region during cancer treatment, severely reduce the quality of life of afflicted patients and can lead to dental caries, periodontitis, digestive disorders, loss of taste and difficulty speaking. Since their initial discovery in the 1970s, P2 purinergic receptors for extracellular nucleotides, including ATP-gated ion channel P2X and G protein-coupled P2Y receptors, have been shown to mediate physiological processes in numerous tissues, including the salivary glands where P2 receptors represent a link between canonical and non-canonical saliva secretion. Additionally, extracellular nucleotides released during periods of cellular stress and inflammation act as a tissue alarmin to coordinate immunological and tissue repair responses through P2 receptor activation. Accordingly, P2 receptors have gained widespread clinical interest with agonists and antagonists either currently undergoing clinical trials or already approved for human use. Here, we review the contributions of P2 receptors to salivary gland function and describe their role in salivary gland dysfunction. We further consider their potential as therapeutic targets to promote physiological saliva flow, prevent salivary gland inflammation and enhance tissue regeneration.
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Affiliation(s)
- Mahmoud G. Khalafalla
- Department of Biochemistry, University of Missouri, Columbia, MO, United States
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, United States
- Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
| | - Lucas T. Woods
- Department of Biochemistry, University of Missouri, Columbia, MO, United States
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, United States
| | - Kimberly J. Jasmer
- Department of Biochemistry, University of Missouri, Columbia, MO, United States
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, United States
| | - Kevin Muñoz Forti
- Department of Biochemistry, University of Missouri, Columbia, MO, United States
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, United States
| | - Jean M. Camden
- Department of Biochemistry, University of Missouri, Columbia, MO, United States
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, United States
| | - Janicke L. Jensen
- Institute of Clinical Dentistry, Section of Oral Surgery and Oral Medicine, University of Oslo, Oslo, Norway
| | - Kirsten H. Limesand
- Department of Nutritional Sciences, University of Arizona, Tucson, AZ, United States
| | - Hilde K. Galtung
- Institute of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway
| | - Gary A. Weisman
- Department of Biochemistry, University of Missouri, Columbia, MO, United States
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, United States
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11
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Lillis T, Veis A, Sakellaridis N, Tsirlis A, Dailiana Z. Effect of clopidogrel in bone healing-experimental study in rabbits. World J Orthop 2019; 10:434-445. [PMID: 31908992 PMCID: PMC6937425 DOI: 10.5312/wjo.v10.i12.434] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 08/27/2019] [Accepted: 09/13/2019] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Clopidogrel is a widely prescribed drug for prevention of myocardial infarction and stroke in patients at risk. It inhibits thrombus formation via inhibition of the P2Y12 purinergic receptor on platelets, which is important in their activation by ADP. However, the P2Y12 receptor has also been found to be expressed in both osteoblasts and osteoclasts. Accumulated evidence suggests that purinergic receptors regulate important functions of bone turnover. Previous studies on the effect of clopidogrel on bone metabolism indicated potential harmful effects, but their results remain conflicting. Thus, clopidogrel treatment may affect bone healing, but it has not yet been studied. AIM To evaluate if continuous perioperative clopidogrel treatment has any negative effect on bone healing in the rabbit calvarial defect model. METHODS Sixteen male white New Zealand rabbits were randomly assigned in two groups: One group received daily 3 mg/kg of clopidogrel per os and the other group received the vehicle alone for a week prior to the surgical procedures; the treatments were continued for another 6 wk postoperatively. The surgical procedures included generation of two circular calvarial defects 11 mm in diameter in every animal. After the 6-wk period of healing, postmortem radiographic and histomorphometric evaluation of the defects was performed. RESULTS Both the surgical procedures and the postoperative period were uneventful and well tolerated by all the animals, without any surgical wound dehiscence, signs of infection or other complication. New bone was formed either inwards from the defect margins or in the central portion of the defect as separated bony islets. While defect healing was still incomplete in both groups, the clopidogrel group had significantly improved radiographic healing scores. Moreover, the histomorphometric analysis showed that bone regeneration (%) was 28.07 ± 7.7 for the clopidogrel group and 19.47 ± 4.9 for the control group, showing a statistically significant difference between them (P = 0.018). Statistically significant difference was also found in the defect bridging (%), i.e. 72.17 ± 21.2 for the clopidogrel group and 41.17 ± 8.5 for the control group, respectively (P = 0.004), whereas there was no statistical difference in bone tissue density between the groups. CONCLUSION Our results indicate that maintenance of perioperative clopidogrel treatment does not negatively affect bone healing but rather promotes it. Further research is needed in order to find useful applications of this finding.
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Affiliation(s)
- Theodoros Lillis
- Department of Orthopaedic Surgery, Faculty of Medicine, University of Thessaly, Biopolis, Larissa 41500, Greece
- Department of Dentoalveolar Surgery, Implantology and Oral Radiology, Faculty of Dentistry, Aristotle University of Thessaloniki, Panepistimioupoli, Thessaloniki 54124, Greece
| | - Alexander Veis
- Department of Dentoalveolar Surgery, Implantology and Oral Radiology, Faculty of Dentistry, Aristotle University of Thessaloniki, Panepistimioupoli, Thessaloniki 54124, Greece
| | - Nikolaos Sakellaridis
- Department of Clinical Pharmacology, Faculty of Medicine, University of Thessaly, Biopolis, Larissa 41500, Greece
| | - Anastasios Tsirlis
- Department of Dentoalveolar Surgery, Implantology and Oral Radiology, Faculty of Dentistry, Aristotle University of Thessaloniki, Panepistimioupoli, Thessaloniki 54124, Greece
| | - Zoe Dailiana
- Department of Orthopaedic Surgery, Faculty of Medicine, University of Thessaly, Biopolis, Larissa 41500, Greece
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12
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Ma C, Kuzma ML, Bai X, Yang J. Biomaterial-Based Metabolic Regulation in Regenerative Engineering. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2019; 6:1900819. [PMID: 31592416 PMCID: PMC6774061 DOI: 10.1002/advs.201900819] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 05/26/2019] [Indexed: 05/22/2023]
Abstract
Recent advances in cell metabolism studies have deepened the appreciation of the role of metabolic regulation in influencing cell behavior during differentiation, angiogenesis, and immune response in the regenerative engineering scenarios. However, the understanding of whether the intracellular metabolic pathways could be influenced by material-derived cues remains limited, although it is now well appreciated that material cues modulate cell functions. Here, an overview of how the regulation of different aspect of cell metabolism, including energy homeostasis, oxygen homeostasis, and redox homeostasis could contribute to modulation of cell function is provided. Furthermore, recent evidence demonstrating how material cues, including the release of inherent metabolic factors (e.g., ions, regulatory metabolites, and oxygen), tuning of the biochemical cues (e.g., inherent antioxidant properties, cell adhesivity, and chemical composition of nanomaterials), and changing in biophysical cues (topography and surface stiffness), may impact cell metabolism toward modulated cell behavior are discussed. Based on the resurgence of interest in cell metabolism and metabolic regulation, further development of biomaterials enabling metabolic regulation toward dictating cell function is poised to have substantial implications for regenerative engineering.
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Affiliation(s)
- Chuying Ma
- Department of Biomedical EngineeringMaterials Research InstituteThe Huck Institutes of the Life SciencesThe Pennsylvania State UniversityUniversity ParkPA16802USA
| | - Michelle L. Kuzma
- Department of Biomedical EngineeringMaterials Research InstituteThe Huck Institutes of the Life SciencesThe Pennsylvania State UniversityUniversity ParkPA16802USA
| | - Xiaochun Bai
- Academy of OrthopedicsGuangdong ProvinceProvincial Key Laboratory of Bone and Joint Degenerative DiseasesThe Third Affiliated Hospital of Southern Medical UniversityGuangzhou510280China
- Department of Cell BiologyKey Laboratory of Mental Health of the Ministry of EducationSchool of Basic Medical SciencesSouthern Medical UniversityGuangzhou510515China
| | - Jian Yang
- Department of Biomedical EngineeringMaterials Research InstituteThe Huck Institutes of the Life SciencesThe Pennsylvania State UniversityUniversity ParkPA16802USA
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13
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Vallon V, Unwin R, Inscho EW, Leipziger J, Kishore BK. Extracellular Nucleotides and P2 Receptors in Renal Function. Physiol Rev 2019; 100:211-269. [PMID: 31437091 DOI: 10.1152/physrev.00038.2018] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The understanding of the nucleotide/P2 receptor system in the regulation of renal hemodynamics and transport function has grown exponentially over the last 20 yr. This review attempts to integrate the available data while also identifying areas of missing information. First, the determinants of nucleotide concentrations in the interstitial and tubular fluids of the kidney are described, including mechanisms of cellular release of nucleotides and their extracellular breakdown. Then the renal cell membrane expression of P2X and P2Y receptors is discussed in the context of their effects on renal vascular and tubular functions. Attention is paid to effects on the cortical vasculature and intraglomerular structures, autoregulation of renal blood flow, tubuloglomerular feedback, and the control of medullary blood flow. The role of the nucleotide/P2 receptor system in the autocrine/paracrine regulation of sodium and fluid transport in the tubular and collecting duct system is outlined together with its role in integrative sodium and fluid homeostasis and blood pressure control. The final section summarizes the rapidly growing evidence indicating a prominent role of the extracellular nucleotide/P2 receptor system in the pathophysiology of the kidney and aims to identify potential therapeutic opportunities, including hypertension, lithium-induced nephropathy, polycystic kidney disease, and kidney inflammation. We are only beginning to unravel the distinct physiological and pathophysiological influences of the extracellular nucleotide/P2 receptor system and the associated therapeutic perspectives.
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Affiliation(s)
- Volker Vallon
- Departments of Medicine and Pharmacology, University of California San Diego & VA San Diego Healthcare System, San Diego, California; Centre for Nephrology, Division of Medicine, University College London, London, United Kingdom; IMED ECD CVRM R&D, AstraZeneca, Gothenburg, Sweden; Department of Medicine, Division of Nephrology, The University of Alabama at Birmingham, Birmingham, Alabama; Department of Biomedicine/Physiology, Aarhus University, Aarhus, Denmark; Departments of Internal Medicine and Nutrition and Integrative Physiology, and Center on Aging, University of Utah Health & Nephrology Research, VA Salt Lake City Healthcare System, Salt Lake City, Utah
| | - Robert Unwin
- Departments of Medicine and Pharmacology, University of California San Diego & VA San Diego Healthcare System, San Diego, California; Centre for Nephrology, Division of Medicine, University College London, London, United Kingdom; IMED ECD CVRM R&D, AstraZeneca, Gothenburg, Sweden; Department of Medicine, Division of Nephrology, The University of Alabama at Birmingham, Birmingham, Alabama; Department of Biomedicine/Physiology, Aarhus University, Aarhus, Denmark; Departments of Internal Medicine and Nutrition and Integrative Physiology, and Center on Aging, University of Utah Health & Nephrology Research, VA Salt Lake City Healthcare System, Salt Lake City, Utah
| | - Edward W Inscho
- Departments of Medicine and Pharmacology, University of California San Diego & VA San Diego Healthcare System, San Diego, California; Centre for Nephrology, Division of Medicine, University College London, London, United Kingdom; IMED ECD CVRM R&D, AstraZeneca, Gothenburg, Sweden; Department of Medicine, Division of Nephrology, The University of Alabama at Birmingham, Birmingham, Alabama; Department of Biomedicine/Physiology, Aarhus University, Aarhus, Denmark; Departments of Internal Medicine and Nutrition and Integrative Physiology, and Center on Aging, University of Utah Health & Nephrology Research, VA Salt Lake City Healthcare System, Salt Lake City, Utah
| | - Jens Leipziger
- Departments of Medicine and Pharmacology, University of California San Diego & VA San Diego Healthcare System, San Diego, California; Centre for Nephrology, Division of Medicine, University College London, London, United Kingdom; IMED ECD CVRM R&D, AstraZeneca, Gothenburg, Sweden; Department of Medicine, Division of Nephrology, The University of Alabama at Birmingham, Birmingham, Alabama; Department of Biomedicine/Physiology, Aarhus University, Aarhus, Denmark; Departments of Internal Medicine and Nutrition and Integrative Physiology, and Center on Aging, University of Utah Health & Nephrology Research, VA Salt Lake City Healthcare System, Salt Lake City, Utah
| | - Bellamkonda K Kishore
- Departments of Medicine and Pharmacology, University of California San Diego & VA San Diego Healthcare System, San Diego, California; Centre for Nephrology, Division of Medicine, University College London, London, United Kingdom; IMED ECD CVRM R&D, AstraZeneca, Gothenburg, Sweden; Department of Medicine, Division of Nephrology, The University of Alabama at Birmingham, Birmingham, Alabama; Department of Biomedicine/Physiology, Aarhus University, Aarhus, Denmark; Departments of Internal Medicine and Nutrition and Integrative Physiology, and Center on Aging, University of Utah Health & Nephrology Research, VA Salt Lake City Healthcare System, Salt Lake City, Utah
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14
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Tezza S, Ben Nasr M, D'Addio F, Vergani A, Usuelli V, Falzoni S, Bassi R, Dellepiane S, Fotino C, Rossi C, Maestroni A, Solini A, Corradi D, Giani E, Mameli C, Bertuzzi F, Pezzolesi MG, Wasserfall CH, Atkinson MA, Füchtbauer EM, Ricordi C, Folli F, Di Virgilio F, Pileggi A, Dhe-Paganon S, Zuccotti GV, Fiorina P. Islet-Derived eATP Fuels Autoreactive CD8 + T Cells and Facilitates the Onset of Type 1 Diabetes. Diabetes 2018; 67:2038-2053. [PMID: 30065030 PMCID: PMC6905486 DOI: 10.2337/db17-1227] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Accepted: 07/06/2018] [Indexed: 01/13/2023]
Abstract
Extracellular ATP (eATP) activates T cells by engaging the P2X7R receptor. We identified two loss-of-function P2X7R mutations that are protective against type 1 diabetes (T1D) and thus hypothesized that eATP/P2X7R signaling may represent an early step in T1D onset. Specifically, we observed that in patients with newly diagnosed T1D, P2X7R is upregulated on CD8+ effector T cells in comparison with healthy control subjects. eATP is released at high levels by human/murine islets in vitro in high-glucose/inflammatory conditions, thus upregulating P2X7R on CD8+ T cells in vitro. P2X7R blockade with oxidized ATP reduces the CD8+ T cell-mediated autoimmune response in vitro and delays diabetes onset in NOD mice. Autoreactive CD8+ T-cell activation is highly dependent upon eATP/P2X7R-mediated priming, while a novel sP2X7R recombinant protein abrogates changes in metabolism and the autoimmune response associated with CD8+ T cells. eATP/P2X7R signaling facilitates the onset of autoimmune T1D by fueling autoreactive CD8+ cells and therefore represents a novel targeted therapeutic for the disorder.
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Affiliation(s)
- Sara Tezza
- Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, MA
| | - Moufida Ben Nasr
- Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, MA
- International Center for Type 1 Diabetes, Pediatric Clinical Romeo and Enrica Invernizzi Research Center, and L. Sacco Department of Biomedical and Clinical Science, University of Milan, Milan, Italy
| | - Francesca D'Addio
- Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, MA
- International Center for Type 1 Diabetes, Pediatric Clinical Romeo and Enrica Invernizzi Research Center, and L. Sacco Department of Biomedical and Clinical Science, University of Milan, Milan, Italy
| | - Andrea Vergani
- Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, MA
| | - Vera Usuelli
- Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, MA
- International Center for Type 1 Diabetes, Pediatric Clinical Romeo and Enrica Invernizzi Research Center, and L. Sacco Department of Biomedical and Clinical Science, University of Milan, Milan, Italy
| | - Simonetta Falzoni
- Department of Morphology, Surgery and Experimental Medicine, University of Ferrara, Ferrara, Italy
| | - Roberto Bassi
- Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, MA
| | - Sergio Dellepiane
- Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, MA
| | - Carmen Fotino
- Diabetes Research Institute, University of Miami, FL
| | - Chiara Rossi
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Anna Maestroni
- International Center for Type 1 Diabetes, Pediatric Clinical Romeo and Enrica Invernizzi Research Center, and L. Sacco Department of Biomedical and Clinical Science, University of Milan, Milan, Italy
| | - Anna Solini
- Department of Surgical, Medical and Molecular Pathology and Critical Care Medicine, University of Pisa, Pisa, Italy
| | - Domenico Corradi
- Pathology and Laboratory Medicine, University of Parma, Parma, Italy
| | - Elisa Giani
- Pediatric Clinical Romeo and Enrica Invernizzi Research Center, L. Sacco Department of Biomedical and Clinical Science, University of Milan, and Department of Pediatrics, Children's Hospital Buzzi, Milan, Italy
| | - Chiara Mameli
- Pediatric Clinical Romeo and Enrica Invernizzi Research Center, L. Sacco Department of Biomedical and Clinical Science, University of Milan, and Department of Pediatrics, Children's Hospital Buzzi, Milan, Italy
| | - Federico Bertuzzi
- Diabetology Unit, ASST Grande Ospedale Metropolitano Niguarda, Milan, Italy
| | - Marcus G Pezzolesi
- Division of Nephrology & Hypertension and Diabetes & Metabolism Research Center, University of Utah, Salt Lake City, UT
| | - Clive H Wasserfall
- Department of Pathology, Immunology and Laboratory Medicine, University of Florida, Gainesville, FL
| | - Mark A Atkinson
- Department of Pathology, Immunology and Laboratory Medicine, University of Florida, Gainesville, FL
| | | | | | - Franco Folli
- Endocrinology and Metabolism, Department of Health Science, University of Milan, Milan, Italy
- ASST Santi Paolo e Carlo, Ospedali San Paolo e San Carlo Borromeo, Milan, Italy
| | - Francesco Di Virgilio
- Department of Morphology, Surgery and Experimental Medicine, University of Ferrara, Ferrara, Italy
| | | | | | - Gian Vincenzo Zuccotti
- International Center for Type 1 Diabetes, Pediatric Clinical Romeo and Enrica Invernizzi Research Center, and L. Sacco Department of Biomedical and Clinical Science, University of Milan, Milan, Italy
- Pediatric Clinical Romeo and Enrica Invernizzi Research Center, L. Sacco Department of Biomedical and Clinical Science, University of Milan, and Department of Pediatrics, Children's Hospital Buzzi, Milan, Italy
| | - Paolo Fiorina
- Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, MA
- International Center for Type 1 Diabetes, Pediatric Clinical Romeo and Enrica Invernizzi Research Center, and L. Sacco Department of Biomedical and Clinical Science, University of Milan, Milan, Italy
- Division of Endocrinology, ASST Fatebenefratelli-Sacco, Milan, Italy
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15
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Abstract
This review summarizes a short list of currently discussed trauma-induced danger-associated molecular patterns (DAMP). Due to the bivalent character and often pleiotropic effects of a DAMP, it is difficult to describe its "friend or foe" role in post-traumatic inflammation and regeneration, both systemically as well locally in tissues. DAMP can be used as biomarkers to indicate or monitor disease or injury severity, but also may serve as clinically applicable parameters for better indication and timing of surgery. Due to the inflammatory processes at the local tissue level or the systemic level, the precise role of DAMP is not always clear to define. While in vitro and experimental studies allow for the detection of these biomarkers at the different levels of an organism-cellular, tissue, circulation-this is not always easily transferable to the human setting. Increased knowledge exploring the dual role of DAMP after trauma, and concentrating on their nuclear functions, transcriptional targets, release mechanisms, cellular sources, multiple functions, their interactions and potential therapeutic targeting is warranted.
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Affiliation(s)
- Borna Relja
- Department of Trauma, Hand and Reconstructive Surgery, University Hospital Frankfurt, Goethe University, 60590, Frankfurt, Germany.
| | - Katharina Mörs
- Department of Trauma, Hand and Reconstructive Surgery, University Hospital Frankfurt, Goethe University, 60590, Frankfurt, Germany
| | - Ingo Marzi
- Department of Trauma, Hand and Reconstructive Surgery, University Hospital Frankfurt, Goethe University, 60590, Frankfurt, Germany
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16
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Zuccarini M, Giuliani P, Buccella S, Di Liberto V, Mudò G, Belluardo N, Carluccio M, Rossini M, Condorelli DF, Rathbone MP, Caciagli F, Ciccarelli R, Di Iorio P. Modulation of the TGF-β1-induced epithelial to mesenchymal transition (EMT) mediated by P1 and P2 purine receptors in MDCK cells. Purinergic Signal 2017; 13:429-442. [PMID: 28616713 PMCID: PMC5714834 DOI: 10.1007/s11302-017-9571-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Accepted: 05/29/2017] [Indexed: 12/17/2022] Open
Abstract
Epithelial to mesenchymal transition (EMT) occurs during embryogenesis or under pathological conditions such as hypoxia, injury, chronic inflammation, or tissue fibrosis. In renal tubular epithelial cells (MDCK), TGF-β1 induces EMT by reducing or increasing epithelial or mesenchymal marker expression, respectively. In this study, we confirmed that the cAMP analogues, 8-CPT-cAMP or N6-Ph-cAMP, inhibited the TGF-β1-driven overexpression of the mesenchymal markers ZEB-1, Slug, Fibronectin, and α-SMA. Furthermore, we showed that A1, A2A, P2Y1, P2Y11, and P2X7 purine receptor agonists modulated the TGF-β1-induced EMT through the involvement of PKA and/or MAPK/ERK signaling. The stimulation of A2A receptor reduced the overexpression of the EMT-related markers, mainly through the cAMP-dependent PKA pathway, as confirmed by cell pre-treatment with Myr-PKI. Both A1 and P2Y1 receptor stimulation exacerbated the TGF-β1-driven effects, which were reduced by cell pre-treatment with the MAPK inhibitor PD98059, according to the increased ERK1/2 phosphorylation upon receptor activation. The effects induced by P2Y11 receptor activation were oppositely modulated by PKA or MAPK inhibition, in line with the dual nature of the Gs- and Gq-coupled receptor. Differently, P2X7 receptor induced, per se, similar and not additive effects compared to TGF-β1, after prolonged cell exposure to BzATP. These results suggest a putative role of purine receptors as target for anti-fibrotic agents.
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Affiliation(s)
- Mariachiara Zuccarini
- Department of Medical and Oral Sciences and Biotechnologies, "G.d'Annunzio" University of Chieti-Pescara, Chieti, Italy.
| | - Patricia Giuliani
- Department of Medical and Oral Sciences and Biotechnologies, "G.d'Annunzio" University of Chieti-Pescara, Chieti, Italy
| | - Silvana Buccella
- Department of Medical and Oral Sciences and Biotechnologies, "G.d'Annunzio" University of Chieti-Pescara, Chieti, Italy
| | - Valentina Di Liberto
- Department of Experimental Biomedicine and Clinical Neurosciences, University of Palermo, Palermo, Italy
| | - Giuseppa Mudò
- Department of Experimental Biomedicine and Clinical Neurosciences, University of Palermo, Palermo, Italy
| | - Natale Belluardo
- Department of Experimental Biomedicine and Clinical Neurosciences, University of Palermo, Palermo, Italy
| | - Marzia Carluccio
- Department of Medical and Oral Sciences and Biotechnologies, "G.d'Annunzio" University of Chieti-Pescara, Chieti, Italy
| | - Margherita Rossini
- Department of Medical and Oral Sciences and Biotechnologies, "G.d'Annunzio" University of Chieti-Pescara, Chieti, Italy
| | | | - Michel Piers Rathbone
- Department of Medicine, Division of Neurology, McMaster University, Hamilton, ON, Canada
| | - Francesco Caciagli
- Department of Medical and Oral Sciences and Biotechnologies, "G.d'Annunzio" University of Chieti-Pescara, Chieti, Italy
| | - Renata Ciccarelli
- Department of Medical and Oral Sciences and Biotechnologies, "G.d'Annunzio" University of Chieti-Pescara, Chieti, Italy
| | - Patrizia Di Iorio
- Department of Medical and Oral Sciences and Biotechnologies, "G.d'Annunzio" University of Chieti-Pescara, Chieti, Italy
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17
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Cell culture: complications due to mechanical release of ATP and activation of purinoceptors. Cell Tissue Res 2017; 370:1-11. [PMID: 28434079 PMCID: PMC5610203 DOI: 10.1007/s00441-017-2618-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Accepted: 03/21/2017] [Indexed: 12/11/2022]
Abstract
There is abundant evidence that ATP (adenosine 5′-triphosphate) is released from a variety of cultured cells in response to mechanical stimulation. The release mechanism involved appears to be a combination of vesicular exocytosis and connexin and pannexin hemichannels. Purinergic receptors on cultured cells mediate both short-term purinergic signalling of secretion and long-term (trophic) signalling such as proliferation, migration, differentiation and apoptosis. We aim in this review to bring to the attention of non-purinergic researchers using tissue culture that the release of ATP in response to mechanical stress evoked by the unavoidable movement of the cells acting on functional purinergic receptors on the culture cells is likely to complicate the interpretation of their data.
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18
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Moriguchi-Mori K, Higashio H, Isobe K, Kumagai M, Sasaki K, Satoh YI, Kuji A, Saino T. P2Y purinoceptors mediate ATP-induced changes in intracellular calcium and amylase release in acinar cells of mouse parotid glands. Biomed Res 2016; 37:37-49. [PMID: 26912139 DOI: 10.2220/biomedres.37.37] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Adenosine 5'-triphosphate (ATP) can act as an extracellular signal that regulates various cellular functions. The present study aimed to determine which purinoceptors play a role in ATP-induced changes in intracellular Ca(2+) ([Ca(2+)]i) and amylase secretion in mouse parotid glands. ATP induced a steep increase in [Ca(2+)]i in acinar cells. The removal of extracellular Ca(2+) or the use of Ca(2+) channel blockers slightly inhibited this increase. Inhibition of PLCγ by U73122 and of IP3 by xestospongin C did not completely block this increase. The purinoceptor antagonists suramin and reactive blue-2 strongly inhibited the ATP-induced changes in [Ca(2+)]i. 2-MeSATP induced a strong increase in [Ca(2+)]i, while Bz-ATP induced a small [Ca(2+)]i increase, and UTP and α,β-MeATP had no effect. The potency order of ATP analogs (2-MeSATP > ATP >> UTP) suggested that P2Y1 and P2Y12 play a significant role in the cellular response to ATP. RT-PCR revealed that P2X2,4,7 and P2Y1,2,10,12,14 were expressed in acinar cells. Ca(2+)-dependent exocytotic secretion of amylase was detected in parotid glands. These findings indicated that ATP activates P2Y receptors more than P2X receptors at low concentrations. Thus, P2Y receptors were found to be the main receptors involved in Ca(2+)-related cell homeostasis and amylase secretion in mouse parotid glands.
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19
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de Almeida-Pereira L, Magalhães CF, Repossi MG, Thorstenberg MLP, Sholl-Franco A, Coutinho-Silva R, Ventura ALM, Fragel-Madeira L. Adenine Nucleotides Control Proliferation In Vivo of Rat Retinal Progenitors by P2Y 1 Receptor. Mol Neurobiol 2016; 54:5142-5155. [PMID: 27558237 DOI: 10.1007/s12035-016-0059-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Accepted: 08/15/2016] [Indexed: 11/30/2022]
Abstract
Previous studies demonstrated that exogenous ATP is able to regulate proliferation of retinal progenitor cells (RPCs) in vitro possibly via P2Y1 receptor, a G protein-coupled receptor. Here, we evaluated the function of adenine nucleotides in vivo during retinal development of newborn rats. Intravitreal injection of apyrase, an enzyme that hydrolyzes nucleotides, reduced cell proliferation in retinas at postnatal day 2 (P2). This decrease was reversed when retinas were treated together with ATPγ-S or ADPβ-S, two hydrolysis-resistant analogs of ATP and ADP, respectively. During early postnatal days (P0 to P5), an increase in ectonucleotidase (E-NTPDase) activity was observed in the retina, suggesting a decrease in the availability of adenine nucleotides, coinciding with the end of proliferation. Interestingly, intravitreal injection of the E-NTPDase inhibitor ARL67156 increased proliferation by around 60 % at P5 rats. Furthermore, immunolabeling against P2Y1 receptor was observed overall in retina layers from P2 rats, including proliferating Ki-67-positive cells in the neuroblastic layer (NBL), suggesting that this receptor could be responsible for the action of adenine nucleotides upon proliferation of RPCs. Accordingly, intravitreal injection of MRS2179, a selective antagonist of P2Y1 receptors, reduced cell proliferation by approximately 20 % in P2 rats. Moreover, treatment with MRS 2179 caused an increase in p57KIP2 and cyclin D1 expression, a reduction in cyclin E and Rb phosphorylated expression and in BrdU-positive cell number. These data suggest that the adenine nucleotides modulate the proliferation of rat RPCs via activation of P2Y1 receptors regulating transition from G1 to S phase of the cell cycle.
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Affiliation(s)
- Luana de Almeida-Pereira
- Department of Neurobiology, Institute of Biology, Fluminense Federal University, Niterói, Brazil
| | - Camila Feitosa Magalhães
- Department of Neurobiology, Institute of Biology, Fluminense Federal University, Niterói, Brazil
| | - Marinna Garcia Repossi
- Department of Neurobiology, Institute of Biology, Fluminense Federal University, Niterói, Brazil
| | | | - Alfred Sholl-Franco
- Institute of Biophysics Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Robson Coutinho-Silva
- Institute of Biophysics Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | | | - Lucianne Fragel-Madeira
- Department of Neurobiology, Institute of Biology, Fluminense Federal University, Niterói, Brazil.
- Laboratório de Desenvolvimento e Regeneração Neural, Departmento de Neurobiologia, Universidade Federal Fluminense, Cx. Postal 100180, Niterói, RJ, 24020-141, Brazil.
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20
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Wright A, Mahaut-Smith M, Symon F, Sylvius N, Ran S, Bafadhel M, Muessel M, Bradding P, Wardlaw A, Vial C. Impaired P2X1 Receptor-Mediated Adhesion in Eosinophils from Asthmatic Patients. THE JOURNAL OF IMMUNOLOGY 2016; 196:4877-84. [PMID: 27183585 DOI: 10.4049/jimmunol.1501585] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Accepted: 04/08/2016] [Indexed: 12/13/2022]
Abstract
Eosinophils play an important role in the pathogenesis of asthma and can be activated by extracellular nucleotides released following cell damage or inflammation. For example, increased ATP concentrations were reported in bronchoalveolar lavage fluids of asthmatic patients. Although eosinophils are known to express several subtypes of P2 receptors for extracellular nucleotides, their function and contribution to asthma remain unclear. In this article, we show that transcripts for P2X1, P2X4, and P2X5 receptors were expressed in healthy and asthmatic eosinophils. The P2X receptor agonist α,β-methylene ATP (α,β-meATP; 10 μM) evoked rapidly activating and desensitizing inward currents (peak 18 ± 3 pA/pF at -60 mV) in healthy eosinophils, typical of P2X1 homomeric receptors, which were abolished by the selective P2X1 antagonist NF449 (1 μM) (3 ± 2 pA/pF). α,β-meATP-evoked currents were smaller in eosinophils from asthmatic patients (8 ± 2 versus 27 ± 5 pA/pF for healthy) but were enhanced following treatment with a high concentration of the nucleotidase apyrase (17 ± 5 pA/pF for 10 IU/ml and 11 ± 3 pA/pF for 0.32 IU/ml), indicating that the channels are partially desensitized by extracellular nucleotides. α,β-meATP (10 μM) increased the expression of CD11b activated form in eosinophils from healthy, but not asthmatic, donors (143 ± 21% and 108 ± 11% of control response, respectively). Furthermore, α,β-meATP increased healthy (18 ± 2% compared with control 10 ± 1%) but not asthmatic (13 ± 1% versus 10 ± 0% for control) eosinophil adhesion. Healthy human eosinophils express functional P2X1 receptors whose activation leads to eosinophil αMβ2 integrin-dependent adhesion. P2X1 responses are constitutively reduced in asthmatic compared with healthy eosinophils, probably as the result of an increase in extracellular nucleotide concentration.
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Affiliation(s)
- Adam Wright
- Institute for Lung Health, National Institute for Health Research Respiratory Biomedical Research Unit, University Hospitals of Leicester National Health Service Trust, Leicester LE3 9QP, United Kingdom
| | - Martyn Mahaut-Smith
- Department of Molecular and Cell Biology, University of Leicester, Leicester LE1 9HN, United Kingdom
| | - Fiona Symon
- Institute for Lung Health, National Institute for Health Research Respiratory Biomedical Research Unit, University Hospitals of Leicester National Health Service Trust, Leicester LE3 9QP, United Kingdom; Department of Infection, Immunity and Inflammation, University of Leicester, Leicester LE1 9HN, United Kingdom
| | - Nicolas Sylvius
- Core Biotechnology Services, University of Leicester, Leicester LE1 9HN, United Kingdom; and
| | - Shaun Ran
- Institute for Lung Health, National Institute for Health Research Respiratory Biomedical Research Unit, University Hospitals of Leicester National Health Service Trust, Leicester LE3 9QP, United Kingdom; Department of Infection, Immunity and Inflammation, University of Leicester, Leicester LE1 9HN, United Kingdom
| | - Mona Bafadhel
- Respiratory Medicine Unit, Nuffield Department of Clinical Medicine, University of Oxford, Oxford OX3 7FZ, United Kingdom
| | - Michelle Muessel
- Institute for Lung Health, National Institute for Health Research Respiratory Biomedical Research Unit, University Hospitals of Leicester National Health Service Trust, Leicester LE3 9QP, United Kingdom; Department of Infection, Immunity and Inflammation, University of Leicester, Leicester LE1 9HN, United Kingdom
| | - Peter Bradding
- Institute for Lung Health, National Institute for Health Research Respiratory Biomedical Research Unit, University Hospitals of Leicester National Health Service Trust, Leicester LE3 9QP, United Kingdom; Department of Infection, Immunity and Inflammation, University of Leicester, Leicester LE1 9HN, United Kingdom
| | - Andrew Wardlaw
- Institute for Lung Health, National Institute for Health Research Respiratory Biomedical Research Unit, University Hospitals of Leicester National Health Service Trust, Leicester LE3 9QP, United Kingdom; Department of Infection, Immunity and Inflammation, University of Leicester, Leicester LE1 9HN, United Kingdom
| | - Catherine Vial
- Institute for Lung Health, National Institute for Health Research Respiratory Biomedical Research Unit, University Hospitals of Leicester National Health Service Trust, Leicester LE3 9QP, United Kingdom; Department of Molecular and Cell Biology, University of Leicester, Leicester LE1 9HN, United Kingdom;
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21
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Tsai SH, Takeda K. Regulation of allergic inflammation by the ectoenzyme E-NPP3 (CD203c) on basophils and mast cells. Semin Immunopathol 2016; 38:571-9. [PMID: 27130555 DOI: 10.1007/s00281-016-0564-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Accepted: 04/26/2016] [Indexed: 01/16/2023]
Abstract
Adenosine 5'-triphosphate (ATP) is released from dying or damaged cells, as well as from activated cells. Once secreted, extracellular ATP induces several immune responses via P2X and P2Y receptors. Basophils and mast cells release ATP upon FcεRI-crosslinking, and ATP activates basophils and mast cells in an autocrine manner. Nucleotide-converting ectoenzymes, such as E-NTPD1, E-NTPD7, and E-NPP3, inhibit ATP-dependent immune responses by hydrolyzing ATP, thereby contributing to immune response regulation. E-NPP3 is a well-known activation marker for human basophils. E-NPP3's physiologic function has recently been disclosed in mice. E-NPP3 is rapidly induced on basophils and mast cells after FcεRI-crosslinking and hydrolyzes extracellular ATP on cell surfaces to prevent ATP-dependent excess activation of basophils and mast cells. In the absence of E-NPP3, basophils and mast cells are overactivated and mice suffer from severe chronic allergic inflammation. Thus, the ATP-hydrolyzing ectoenzymes E-NPP3 has a nonnegligible role in the regulation of basophil- and mast cell-mediated allergic responses.
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Affiliation(s)
- Shih Han Tsai
- Laboratory of Immune Regulation, Department of Microbiology and Immunology, Graduate School of Medicine, WPI Immunology Frontier Research Center, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Kiyoshi Takeda
- Laboratory of Immune Regulation, Department of Microbiology and Immunology, Graduate School of Medicine, WPI Immunology Frontier Research Center, Osaka University, Suita, Osaka, 565-0871, Japan. .,Core Research for Evolutional Science and Technology, Japan Agency for Medical Research and Development, Tokyo, 100-0004, Japan.
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22
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Bhattacharya S, Imbery JF, Ampem PT, Giovannucci DR. Crosstalk between purinergic receptors and canonical signaling pathways in the mouse salivary gland. Cell Calcium 2015; 58:589-97. [PMID: 26443524 DOI: 10.1016/j.ceca.2015.09.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Revised: 09/22/2015] [Accepted: 09/25/2015] [Indexed: 01/21/2023]
Abstract
Isolated clusters of mouse parotid acinar cells in combination with live cell imaging were used to explore the crosstalk in molecular signaling between purinergic, cholinergic and adrenergic pathways that integrate to control fluid and protein secretion. This crosstalk was manifested by (1) β-adrenergic receptor activation and amplification of P2X4R evoked Ca(2+) signals, (2) β-adrenergic-induced amplification of P2X7R-evoked Ca(2+) signals and (3) muscarinic receptor induced activation of P2X7Rs via exocytotic activity. The findings from our study reveal that purinoceptor-mediated Ca(2+) signaling is modulated by crosstalk with canonical signaling pathways in parotid acinar cells. Integration of these signals are likely important for dynamic control of saliva secretion to match physiological demand in the parotid gland.
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Affiliation(s)
- Sumit Bhattacharya
- Department of Neurosciences, University of Toledo Medical Center, 3000 Arlington Avenue, Toledo, OH 43614, USA
| | - John F Imbery
- Department of Neurosciences, University of Toledo Medical Center, 3000 Arlington Avenue, Toledo, OH 43614, USA
| | - Prince Tuffour Ampem
- Department of Neurosciences, University of Toledo Medical Center, 3000 Arlington Avenue, Toledo, OH 43614, USA
| | - David R Giovannucci
- Department of Neurosciences, University of Toledo Medical Center, 3000 Arlington Avenue, Toledo, OH 43614, USA.
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23
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Colgan SP, Curtis VF, Lanis JM, Glover LE. Metabolic regulation of intestinal epithelial barrier during inflammation. Tissue Barriers 2015; 3:e970936. [PMID: 25838978 DOI: 10.4161/21688362.2014.970936] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Accepted: 09/25/2014] [Indexed: 12/21/2022] Open
Abstract
The gastrointestinal mucosa has proven to be an interesting tissue for which to investigate disease-related metabolism. In this review, we outline some evidence that implicates metabolic signaling as important features of barrier in the healthy and disease. Studies from cultured cell systems, animal models and human patients have revealed that metabolites generated within the inflammatory microenvironment are central to barrier regulation. These studies have revealed a prominent role for hypoxia and hypoxia-inducible factor (HIF) at key steps in adenine nucleotide metabolism and within the creatine kinase pathway. Results from animal models of intestinal inflammation have demonstrated an almost uniformly beneficial influence of HIF stabilization on disease outcomes and barrier function. Studies underway to elucidate the contribution of immune responses will provide additional insight into how metabolic changes contribute to the complexity of the gastrointestinal tract and how such information might be harnessed for therapeutic benefit.
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Key Words
- AMP, adenosine monophosphate
- CK, creatine kinase
- ChIP, chromatin immunoprecipitation
- Colitis
- HIF, hypoxia-inducible factor
- PHD, prolyl hydroxylase
- PMN, polymorphonuclear leukcoyte, neutrophil
- TJ, tight junction
- VASP, vasodilator-stimulated
- ZO-1, zonula occludens-1
- creatine
- epithelium
- inflammation
- metabolism
- mucosa
- murine model
- neutrophil
- nucleoside
- nucleotidase
- nucleotide
- phosphocreatine
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Affiliation(s)
- Sean P Colgan
- Departments of Medicine and the Mucosal Inflammation Program; University of Colorado School of Medicine ; Aurora, CO USA
| | - Valerie F Curtis
- Departments of Medicine and the Mucosal Inflammation Program; University of Colorado School of Medicine ; Aurora, CO USA
| | - Jordi M Lanis
- Departments of Medicine and the Mucosal Inflammation Program; University of Colorado School of Medicine ; Aurora, CO USA
| | - Louise E Glover
- Departments of Medicine and the Mucosal Inflammation Program; University of Colorado School of Medicine ; Aurora, CO USA
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24
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Signalling molecules in the urothelium. BIOMED RESEARCH INTERNATIONAL 2014; 2014:297295. [PMID: 25177686 PMCID: PMC4142380 DOI: 10.1155/2014/297295] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Revised: 07/18/2014] [Accepted: 07/18/2014] [Indexed: 12/14/2022]
Abstract
The urothelium was long considered to be a silent barrier protecting the body from the toxic effects of urine. However, today a number of dynamic abilities of the urothelium are well recognized, including its ability to act as a sensor of the intravesical environment. During recent years several pathways of these urothelial abilities have been proposed and a major part of these pathways includes release of signalling molecules. It is now evident that the urothelium represents only one part of the sensory web. Urinary bladder signalling is finely tuned machinery of signalling molecules, acting in autocrine and paracrine manner, and their receptors are specifically distributed among different types of cells in the urinary bladder. In the present review the current knowledge of the formation, release, and signalling effects of urothelial acetylcholine, ATP, adenosine, and nitric oxide in health and disease is discussed.
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25
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Haanes KA, Kowal JM, Arpino G, Lange SC, Moriyama Y, Pedersen PA, Novak I. Role of vesicular nucleotide transporter VNUT (SLC17A9) in release of ATP from AR42J cells and mouse pancreatic acinar cells. Purinergic Signal 2014; 10:431-40. [PMID: 24488439 DOI: 10.1007/s11302-014-9406-7] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Accepted: 01/08/2014] [Indexed: 12/11/2022] Open
Abstract
ATP is released from cells in response to various stimuli. Our previous studies on pancreas indicated that pancreatic acini could be major stores of secreted ATP. In the present study, our aim was to establish the role of the vesicular nucleotide transporter (VNUT), SLC17A9, in storage and release of ATP. Freshly prepared acini from mice and AR42J rat acinar cells were used in this study. We illustrate that in AR42J cells, quinacrine (an ATP store marker) and Bodipy ATP (a fluorescent ATP analog) co-localized with VNUT-mCherry to vesicles/granules. Furthermore, in acini and AR42J cells, a marker of the zymogen granule membranes, Rab3D, and VNUT co-localized. Dexamethasone treatment of AR42J cells promoted formation of acinar structures, paralleled by increased amylase and VNUT expression, and increased ATP release in response to cholinergic stimulation. Mechanical stimulus (pressure) and cell swelling also induced ATP release, but this was not influenced by dexamethasone, most likely indicating different non-zymogen-related release mechanism. In conclusion, we propose that VNUT-dependent ATP release pathway is associated with agonist-induced secretion process and downstream purinergic signalling in pancreatic ducts.
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Affiliation(s)
- K A Haanes
- Department of Biology, Section Molecular Integrative Physiology, University of Copenhagen, August Krogh Building, Universitetsparken 13, Copenhagen, 2100, Denmark
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26
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Calcium phosphate-bearing matrices induce osteogenic differentiation of stem cells through adenosine signaling. Proc Natl Acad Sci U S A 2014; 111:990-5. [PMID: 24395775 DOI: 10.1073/pnas.1321717111] [Citation(s) in RCA: 246] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Synthetic matrices emulating the physicochemical properties of tissue-specific ECMs are being developed at a rapid pace to regulate stem cell fate. Biomaterials containing calcium phosphate (CaP) moieties have been shown to support osteogenic differentiation of stem and progenitor cells and bone tissue formation. By using a mineralized synthetic matrix mimicking a CaP-rich bone microenvironment, we examine a molecular mechanism through which CaP minerals induce osteogenesis of human mesenchymal stem cells with an emphasis on phosphate metabolism. Our studies show that extracellular phosphate uptake through solute carrier family 20 (phosphate transporter), member 1 (SLC20a1) supports osteogenic differentiation of human mesenchymal stem cells via adenosine, an ATP metabolite, which acts as an autocrine/paracrine signaling molecule through A2b adenosine receptor. Perturbation of SLC20a1 abrogates osteogenic differentiation by decreasing intramitochondrial phosphate and ATP synthesis. Collectively, this study offers the demonstration of a previously unknown mechanism for the beneficial role of CaP biomaterials in bone repair and the role of phosphate ions in bone physiology and regeneration. These findings also begin to shed light on the role of ATP metabolism in bone homeostasis, which may be exploited to treat bone metabolic diseases.
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27
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Vergani A, Fotino C, D’Addio F, Tezza S, Podetta M, Gatti F, Chin M, Bassi R, Molano RD, Corradi D, Gatti R, Ferrero ME, Secchi A, Grassi F, Ricordi C, Sayegh MH, Maffi P, Pileggi A, Fiorina P. Effect of the purinergic inhibitor oxidized ATP in a model of islet allograft rejection. Diabetes 2013; 62:1665-75. [PMID: 23315496 PMCID: PMC3636636 DOI: 10.2337/db12-0242] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The lymphocytic ionotropic purinergic P2X receptors (P2X1R-P2X7R, or P2XRs) sense ATP released during cell damage-activation, thus regulating T-cell activation. We aim to define the role of P2XRs during islet allograft rejection and to establish a novel anti-P2XRs strategy to achieve long-term islet allograft function. Our data demonstrate that P2X1R and P2X7R are induced in islet allograft-infiltrating cells, that only P2X7R is increasingly expressed during alloimmune response, and that P2X1R is augmented in both allogeneic and syngeneic transplantation. In vivo short-term P2X7R targeting (using periodate-oxidized ATP [oATP]) delays islet allograft rejection, reduces the frequency of Th1/Th17 cells, and induces hyporesponsiveness toward donor antigens. oATP-treated mice displayed preserved islet grafts with reduced Th1 transcripts. P2X7R targeting and rapamycin synergized in inducing long-term islet function in 80% of transplanted mice and resulted in reshaping of the recipient immune system. In vitro P2X7R targeting using oATP reduced T-cell activation and diminished Th1/Th17 cytokine production. Peripheral blood mononuclear cells obtained from long-term islet-transplanted patients showed an increased percentage of P2X7R⁺CD4⁺ T cells compared with controls. The beneficial effects of oATP treatment revealed a role for the purinergic system in islet allograft rejection, and the targeting of P2X7R is a novel strategy to induce long-term islet allograft function.
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MESH Headings
- Adenosine Triphosphate/analogs & derivatives
- Adenosine Triphosphate/therapeutic use
- Adult
- Animals
- Female
- Graft Rejection/prevention & control
- Humans
- Immunosuppression Therapy
- Immunosuppressive Agents/therapeutic use
- Islets of Langerhans Transplantation/adverse effects
- Islets of Langerhans Transplantation/immunology
- Islets of Langerhans Transplantation/pathology
- Male
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Mice, Knockout
- Middle Aged
- Purinergic P2X Receptor Antagonists/therapeutic use
- Receptors, Purinergic P2X7/chemistry
- Receptors, Purinergic P2X7/genetics
- Receptors, Purinergic P2X7/metabolism
- Sirolimus/therapeutic use
- T-Lymphocyte Subsets/drug effects
- T-Lymphocyte Subsets/immunology
- Transplantation, Heterotopic/adverse effects
- Transplantation, Heterotopic/immunology
- Transplantation, Heterotopic/pathology
- Transplantation, Homologous
- Transplantation, Isogeneic
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Affiliation(s)
- Andrea Vergani
- Transplantation Research Center, Nephrology Division, Boston Children’s Hospital and Brigham and Women’s Hospital/Harvard Medical School, Boston, Massachusetts
- Transplant Medicine, San Raffaele Scientific Institute, Milan, Italy
| | - Carmen Fotino
- Diabetes Research Institute, University of Miami, Miami, Florida
| | - Francesca D’Addio
- Transplant Medicine, San Raffaele Scientific Institute, Milan, Italy
| | - Sara Tezza
- Transplantation Research Center, Nephrology Division, Boston Children’s Hospital and Brigham and Women’s Hospital/Harvard Medical School, Boston, Massachusetts
| | - Michele Podetta
- Diabetes Research Institute, University of Miami, Miami, Florida
| | - Francesca Gatti
- Transplantation Research Center, Nephrology Division, Boston Children’s Hospital and Brigham and Women’s Hospital/Harvard Medical School, Boston, Massachusetts
| | - Melissa Chin
- Transplantation Research Center, Nephrology Division, Boston Children’s Hospital and Brigham and Women’s Hospital/Harvard Medical School, Boston, Massachusetts
| | - Roberto Bassi
- Transplantation Research Center, Nephrology Division, Boston Children’s Hospital and Brigham and Women’s Hospital/Harvard Medical School, Boston, Massachusetts
| | - Ruth D. Molano
- Diabetes Research Institute, University of Miami, Miami, Florida
| | - Domenico Corradi
- Pathology and Laboratory Medicine, University of Parma, Parma, Italy
| | - Rita Gatti
- Pathology and Laboratory Medicine, University of Parma, Parma, Italy
| | - Maria E. Ferrero
- Department of Human Morphology and Biomedical Science, University of Milan, Milan, Italy
| | - Antonio Secchi
- Transplant Medicine, San Raffaele Scientific Institute, Milan, Italy
- Vita-Salute San Raffaele University, Milan, Italy
| | - Fabio Grassi
- Institute for Research in Biomedicine, Bellinzona, Switzerland
| | - Camillo Ricordi
- Diabetes Research Institute, University of Miami, Miami, Florida
| | - Mohamed H. Sayegh
- Transplantation Research Center, Nephrology Division, Boston Children’s Hospital and Brigham and Women’s Hospital/Harvard Medical School, Boston, Massachusetts
| | - Paola Maffi
- Transplant Medicine, San Raffaele Scientific Institute, Milan, Italy
| | | | - Paolo Fiorina
- Transplantation Research Center, Nephrology Division, Boston Children’s Hospital and Brigham and Women’s Hospital/Harvard Medical School, Boston, Massachusetts
- Transplant Medicine, San Raffaele Scientific Institute, Milan, Italy
- Corresponding author: Paolo Fiorina,
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28
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Choi RCY, Chu GKY, Siow NL, Yung AWY, Yung LY, Lee PSC, Lo CCW, Simon J, Dong TTX, Barnard EA, Tsim KWK. Activation of UTP-sensitive P2Y2 receptor induces the expression of cholinergic genes in cultured cortical neurons: a signaling cascade triggered by Ca2+ mobilization and extracellular regulated kinase phosphorylation. Mol Pharmacol 2013; 84:50-61. [PMID: 23592515 DOI: 10.1124/mol.112.084160] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
ATP functions as an extracellular signaling molecule that is costored and coreleased with neurotransmitters at central and peripheral neuronal synapses. Stimulation by ATP upregulates the expression of synaptic genes in muscle-including the genes for nicotine acetylcholine receptor (α-, δ-, and ε-subunits) and acetylcholinesterase (AChE)-via the P2Y receptor (P2YR), but the trophic response of neurons to the activation of P2YRs is less well understood. We reported that cultured cortical neurons and the developing rat brain expressed different types of P2YRs, and among these the UTP-sensitive P2Y2R was the most abundant. P2Y2R was found to exist in membrane rafts and it colocalized with the postsynaptic protein PSD-95 in cortical neurons. Notably, agonist-dependent stimulation of P2Y2R elevated the neuronal expression of cholinergic genes encoding AChE, PRiMA (an anchor for the globular form AChE), and choline acetyltransferase, and this induction was mediated by a signaling cascade that involved Ca(2+) mobilization and extracellular regulated kinases 1/2 activation. The importance of P2Y2R action was further shown by the receptor's synergistic effect with P2Y1R in enhancing cholinergic gene expression via the robust stimulation of Ca(2+) influx. Taken together our results revealed a developmental function of P2Y2R in promoting synaptic gene expression and demonstrated the influence of costimulation of P2Y1R and P2Y2R in neurons.
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Affiliation(s)
- Roy C Y Choi
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China.
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29
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Regateiro FS, Cobbold SP, Waldmann H. CD73 and adenosine generation in the creation of regulatory microenvironments. Clin Exp Immunol 2013. [PMID: 23199317 DOI: 10.1111/j.1365-2249.2012.04623.x] [Citation(s) in RCA: 121] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Extracellular adenosine 5'-triphosphate (ATP) acts on many immune cells to promote inflammation. Conversely, the ATP metabolite adenosine is mainly an anti-inflammatory molecule. The ecto-enzymes CD39 and CD73 can dephosphorylate extracellular ATP to adenosine, thereby controlling this important pathway of immune modulation. Despite their established roles in the immune system, little is known of how CD39 and CD73 are themselves regulated. Recent data have shown that CD73 expression and adenosine generation are up-regulated by transforming growth factor-β, depending on the cytokine content of the local microenvironment. We review here these recent findings and discuss their implications in disease.
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Affiliation(s)
- F S Regateiro
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
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30
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Colgan SP, Fennimore B, Ehrentraut SF. Adenosine and gastrointestinal inflammation. J Mol Med (Berl) 2013; 91:157-64. [PMID: 23296303 DOI: 10.1007/s00109-012-0990-0] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Revised: 12/04/2012] [Accepted: 12/18/2012] [Indexed: 12/23/2022]
Abstract
Nucleosides such as adenosine (Ado) influence nearly every aspect of physiology and pathophysiology. Extracellular nucleotides liberated at local sites of inflammation are metabolized through regulated phosphohydrolysis by a series of ecto-nucleotidases including ectonucleoside triphosphate diphosphohydrolase-1 (CD39) and ecto-5'-nucleotidase (CD73), found on the surface of a variety of cell types. Once generated, Ado is made available to bind and activate one of four G protein-coupled Ado receptors. Recent in vitro and in vivo studies implicate Ado in a broad array of tissue-protective mechanisms that provide new insight into adenosine actions. Studies in cultured cells and murine tissues have indicated that Ado receptors couple to novel posttranslational protein modifications, including Cullin deneddylation, as a new anti-inflammatory mechanism. Studies in Ado receptor-null mice have been revealing and indicate a particularly important role for the Ado A2B receptor in animal models of intestinal inflammation. Here, we review contributions of Ado to cell and tissue stress responses, with a particular emphasis on the gastrointestinal mucosa.
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Affiliation(s)
- Sean P Colgan
- Department of Medicine and Mucosal Inflammation Program, University of Colorado School of Medicine, 12700 East 19th Ave., MS B-146, Aurora, CO 80045, USA.
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31
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Vergani A, Tezza S, D'Addio F, Fotino C, Liu K, Niewczas M, Bassi R, Molano RD, Kleffel S, Petrelli A, Soleti A, Ammirati E, Frigerio M, Visner G, Grassi F, Ferrero ME, Corradi D, Abdi R, Ricordi C, Sayegh MH, Pileggi A, Fiorina P. Long-term heart transplant survival by targeting the ionotropic purinergic receptor P2X7. Circulation 2012; 127:463-75. [PMID: 23250993 DOI: 10.1161/circulationaha.112.123653] [Citation(s) in RCA: 90] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND Heart transplantation is a lifesaving procedure for patients with end-stage heart failure. Despite much effort and advances in the field, current immunosuppressive regimens are still associated with poor long-term cardiac allograft outcomes, and with the development of complications, including infections and malignancies, as well. The development of a novel, short-term, and effective immunomodulatory protocol will thus be an important achievement. The purine ATP, released during cell damage/activation, is sensed by the ionotropic purinergic receptor P2X7 (P2X7R) on lymphocytes and regulates T-cell activation. Novel clinical-grade P2X7R inhibitors are available, rendering the targeting of P2X7R a potential therapy in cardiac transplantation. METHODS AND RESULTS We analyzed P2X7R expression in patients and mice and P2X7R targeting in murine recipients in the context of cardiac transplantation. Our data demonstrate that P2X7R is specifically upregulated in graft-infiltrating lymphocytes in cardiac-transplanted humans and mice. Short-term P2X7R targeting with periodate-oxidized ATP promotes long-term cardiac transplant survival in 80% of murine recipients of a fully mismatched allograft. Long-term survival of cardiac transplants was associated with reduced T-cell activation, T-helper cell 1/T-helper cell 17 differentiation, and inhibition of STAT3 phosphorylation in T cells, thus leading to a reduced transplant infiltrate and coronaropathy. In vitro genetic upregulation of the P2X7R pathway was also shown to stimulate T-helper cell 1/T-helper cell 17 cell generation. Finally, P2X7R targeting halted the progression of coronaropathy in a murine model of chronic rejection as well. CONCLUSIONS P2X7R targeting is a novel clinically relevant strategy to prolong cardiac transplant survival.
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Affiliation(s)
- Andrea Vergani
- Transplantation Research Center, Boston Children's Hospital, Harvard Medical School, Enders Building 5th floor, Rm EN530, 300 Longwood Ave, Boston, MA 02115, USA
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32
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Stenmark KR, Yeager ME, El Kasmi KC, Nozik-Grayck E, Gerasimovskaya EV, Li M, Riddle SR, Frid MG. The adventitia: essential regulator of vascular wall structure and function. Annu Rev Physiol 2012; 75:23-47. [PMID: 23216413 PMCID: PMC3762248 DOI: 10.1146/annurev-physiol-030212-183802] [Citation(s) in RCA: 273] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The vascular adventitia acts as a biological processing center for the retrieval, integration, storage, and release of key regulators of vessel wall function. It is the most complex compartment of the vessel wall and is composed of a variety of cells, including fibroblasts, immunomodulatory cells (dendritic cells and macrophages), progenitor cells, vasa vasorum endothelial cells and pericytes, and adrenergic nerves. In response to vascular stress or injury, resident adventitial cells are often the first to be activated and reprogrammed to influence the tone and structure of the vessel wall; to initiate and perpetuate chronic vascular inflammation; and to stimulate expansion of the vasa vasorum, which can act as a conduit for continued inflammatory and progenitor cell delivery to the vessel wall. This review presents the current evidence demonstrating that the adventitia acts as a key regulator of vascular wall function and structure from the outside in.
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Affiliation(s)
- Kurt R. Stenmark
- University of Colorado Denver, Division of Pediatric Critical Care, Aurora, CO 80045
| | - Michael E. Yeager
- University of Colorado Denver, Division of Pediatric Critical Care, Aurora, CO 80045
| | - Karim C. El Kasmi
- University of Colorado Denver, Division of Pediatric Critical Care, Aurora, CO 80045
| | - Eva Nozik-Grayck
- University of Colorado Denver, Division of Pediatric Critical Care, Aurora, CO 80045
| | | | - Min Li
- University of Colorado Denver, Division of Pediatric Critical Care, Aurora, CO 80045
| | - Suzette R. Riddle
- University of Colorado Denver, Division of Pediatric Critical Care, Aurora, CO 80045
| | - Maria G. Frid
- University of Colorado Denver, Division of Pediatric Critical Care, Aurora, CO 80045
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33
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Abstract
Pancreatic cells contain specialised stores for ATP. Purinergic receptors (P2 and P1) and ecto-nucleotidases are expressed in both endocrine and exocrine calls, as well as in stromal cells. The pancreas, especially the endocrine cells, were an early target for the actions of ATP. After the historical perspective of purinergic signalling in the pancreas, the focus of this review will be the physiological functions of purinergic signalling in the regulation of both endocrine and exocrine pancreas. Next, we will consider possible interaction between purinergic signalling and other regulatory systems and their relation to nutrient homeostasis and cell survival. The pancreas is an organ exhibiting several serious diseases - cystic fibrosis, pancreatitis, pancreatic cancer and diabetes - and some are associated with changes in life-style and are increasing in incidence. There is upcoming evidence for the role of purinergic signalling in the pathophysiology of the pancreas, and the new challenge is to understand how it is integrated with other pathological processes.
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Affiliation(s)
- G Burnstock
- University College Medical School, Autonomic Neuroscience Centre, Rowland Hill Street, London NW3 2PF, UK.
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34
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Lee MG, Ohana E, Park HW, Yang D, Muallem S. Molecular mechanism of pancreatic and salivary gland fluid and HCO3 secretion. Physiol Rev 2012; 92:39-74. [PMID: 22298651 DOI: 10.1152/physrev.00011.2011] [Citation(s) in RCA: 275] [Impact Index Per Article: 22.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Fluid and HCO(3)(-) secretion is a vital function of all epithelia and is required for the survival of the tissue. Aberrant fluid and HCO(3)(-) secretion is associated with many epithelial diseases, such as cystic fibrosis, pancreatitis, Sjögren's syndrome, and other epithelial inflammatory and autoimmune diseases. Significant progress has been made over the last 20 years in our understanding of epithelial fluid and HCO(3)(-) secretion, in particular by secretory glands. Fluid and HCO(3)(-) secretion by secretory glands is a two-step process. Acinar cells secrete isotonic fluid in which the major salt is NaCl. Subsequently, the duct modifies the volume and electrolyte composition of the fluid to absorb the Cl(-) and secrete HCO(3)(-). The relative volume secreted by acinar and duct cells and modification of electrolyte composition of the secreted fluids varies among secretory glands to meet their physiological functions. In the pancreas, acinar cells secrete a small amount of NaCl-rich fluid, while the duct absorbs the Cl(-) and secretes HCO(3)(-) and the bulk of the fluid in the pancreatic juice. Fluid secretion appears to be driven by active HCO(3)(-) secretion. In the salivary glands, acinar cells secrete the bulk of the fluid in the saliva that is driven by active Cl(-) secretion and contains high concentrations of Na(+) and Cl(-). The salivary glands duct absorbs both the Na(+) and Cl(-) and secretes K(+) and HCO(3)(-). In this review, we focus on the molecular mechanism of fluid and HCO(3)(-) secretion by the pancreas and salivary glands, to highlight the similarities of the fundamental mechanisms of acinar and duct cell functions, and to point out the differences to meet gland-specific secretions.
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Affiliation(s)
- Min Goo Lee
- Department of Pharmacology, Yonsei University College of Medicine, Seoul, Korea
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Bhattacharya S, Verrill DS, Carbone KM, Brown S, Yule DI, Giovannucci DR. Distinct contributions by ionotropic purinoceptor subtypes to ATP-evoked calcium signals in mouse parotid acinar cells. J Physiol 2012; 590:2721-37. [PMID: 22451435 DOI: 10.1113/jphysiol.2012.228148] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
There is emerging consensus that P2X₄ and P2X₇ ionotropic purinoceptors (P2X₄R and P2X₇R) are critical players in regulating [Ca²⁺]i dynamics and fluid secretion in the salivary gland. In contrast, details regarding their compartmentalization and selective activation, contributions to the spatiotemporal properties of intracellular signals and roles in regulating protein exocytosis and ion channel activity have remained largely undefined. To address these concerns, we profiled mouse parotid acinar cells using live-cell imaging to follow the spatial and temporal features of ATP-evoked Ca²⁺ dynamics and exocytotic activity. Selective activation of P2X7Rs revealed an apical-to-basal [Ca²⁺]i signal that initiated at the sub-luminal border and propagated with a wave speed estimated at 17.3 ± 4.3 μm s⁻¹ (n =6). The evoked Ca²⁺ spike consisted of Ca²⁺ influx and Ca²⁺-induced Ca²⁺ release from intracellular Ca²⁺ channels. In contrast, selective activation of P2X₄Rs induced a Ca²⁺ signal that initiated basally and propagated toward the lumen with a wave speed of 4.3 ± 0.2 μm s⁻¹ (n =8) that was largely independent of intracellular Ca²⁺ channel blockade. Consistent with these observations, P2X₇R expression was enriched in the sub-luminal regions of acinar cells while P2X₄R appeared localized to basal areas. In addition, we showed that P2X₄R and P2X₇R activation evokes exocytosis in parotid acinar cells. Our studies also demonstrate that the P2X₄R-mediated [Ca²⁺]i rise and subsequent protein exocytosis was enhanced by ivermectin (IVR). Thus, in addition to furthering our understanding of salivary gland physiology, this study identifies P2X₄R as a potential target for treatment of salivary hypofunction diseases.
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Affiliation(s)
- Sumit Bhattacharya
- Department of Neurosciences, University of Toledo College of Medicine, Toledo, OH, USA
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Kelly CJ, Colgan SP. Targeting Hypoxia to Augment Mucosal Barrier Function. JOURNAL OF EPITHELIAL BIOLOGY & PHARMACOLOGY 2012; 5:67-76. [PMID: 28824735 PMCID: PMC5560425 DOI: 10.2174/1875044301205010067] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Sites of inflammation are associated with profound changes in tissue metabolism. Studies in vitro and in vivo have shown that the activation of the hypoxia-inducible factor (HIF) serves as an adaptive pathway for the resolution of inflammation associated with various murine disease models. The resolution of disease occurs, at least in part, through transcriptional regulation of non-classical epithelial barrier genes. There is significant recent interest in harnessing hypoxia-inducible pathways, including targeting the HIF and the proyl-hydroxylase (PHD) enzymes that stabilize HIF, to promote mucosal healing. Here, we review the signaling pathways involved and define how hypoxia-associated signaling provides mechanistic insight into augmenting barrier function in mucosal inflammatory disease.
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Affiliation(s)
- Caleb J Kelly
- Mucosal Inflammation Program, Department of Medicine, University of Colorado Health Sciences Center, Aurora, CO USA
| | - Sean P Colgan
- Mucosal Inflammation Program, Department of Medicine, University of Colorado Health Sciences Center, Aurora, CO USA
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Colgan SP, Eltzschig HK. Adenosine and hypoxia-inducible factor signaling in intestinal injury and recovery. Annu Rev Physiol 2011; 74:153-75. [PMID: 21942704 DOI: 10.1146/annurev-physiol-020911-153230] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The gastrointestinal mucosa has proven to be an interesting tissue in which to investigate disease-related metabolism. In this review, we outline some of the evidence that implicates hypoxia-mediated adenosine signaling as an important signature within both healthy and diseased mucosa. Studies derived from cultured cell systems, animal models, and human patients have revealed that hypoxia is a significant component of the inflammatory microenvironment. These studies have revealed a prominent role for hypoxia-induced factor (HIF) and hypoxia signaling at several steps along the adenine nucleotide metabolism and adenosine receptor signaling pathways. Likewise, studies to date in animal models of intestinal inflammation have demonstrated an almost uniformly beneficial influence of HIF stabilization on disease outcomes. Ongoing studies to define potential similarities with and differences between innate and adaptive immune responses will continue to teach us important lessons about the complexity of the gastrointestinal tract. Such information has provided new insights into disease pathogenesis and, importantly, will provide insights into new therapeutic targets.
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Affiliation(s)
- Sean P Colgan
- Departments of Medicine and Anesthesiology and the Mucosal Inflammation Program, University of Colorado School of Medicine, Aurora, Colorado 80045, USA.
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Abstract
The common theme of this introductory article and the minireviews that follow in this special issue is the concept of microenvironments within tissues and surrounding cells that would be ideal signaling venues for a biologically active purinergic ligand. Collectively, the editors/authors and the other contributing authors agree that nucleotides and nucleosides would be most potent within a confined system. A talented cadre of purinergics has been solicited to discuss purinergic signaling in his or her favorite microenvironment within a given organ or tissue. We are gratified by the large number of original articles that also have successfully navigated the peer review process and are part of this special issue. These concepts are not simply purinergic, but the idea of maximal potency in a tissue microenvironment and surrounding specialized cells within a tissue pertains to any autacoid or paracrine agonist.
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Affiliation(s)
- Erik M Schwiebert
- Departments of Physiology and Biophysics and Cell Biology, University of Alabama at Birmingham, Birmingham, AL, USA.
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Czarnecka J, Roszek K, Jabłoński A, Smoliński DJ, Komoszyński M. Some aspects of purinergic signaling in the ventricular system of porcine brain. Acta Vet Scand 2011; 53:54. [PMID: 21995888 PMCID: PMC3213016 DOI: 10.1186/1751-0147-53-54] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2011] [Accepted: 10/13/2011] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND Numerous signaling pathways function in the brain ventricular system, including the most important - GABAergic, glutaminergic and dopaminergic signaling. Purinergic signalization system - comprising nucleotide receptors, nucleotidases, ATP and adenosine and their degradation products - are also present in the brain. However, the precise role of nucleotide signalling pathway in the ventricular system has been not elucidated so far. The aim of our research was the identification of all three elements of purinergic signaling pathway in the porcine brain ventricular system. RESULTS Besides nucleotide receptors on the ependymocytes surface, we studied purines and pyrimidines in the CSF, including mechanisms of nucleotide signaling in the swine model (Sus scrofa domestica). The results indicate presence of G proteins coupled P2Y receptors on ependymocytes and also P2X receptors engaged in fast signal transmission. Additionally we found in CSF nucleotides and adenosine in the concentration sufficient to P receptors activation. These extracellular nucleotides are metabolised by adenylate kinase and nucleotidases from at least two families: NTPDases and NPPases. A low activity of these nucleotide metabolising enzymes maintains nucleotides concentration in ventricular system in micromolar range. ATP is degraded into adenosine and inosine. CONCLUSIONS Our results confirm the thesis about cross-talking between brain and ventricular system functioning in physiological as well as pathological conditions. The close interaction of brain and ventricular system may elicit changes in qualitative and quantitative composition of purines and pyrimidines in CSF. These changes can be dependent on the physiological state of brain, including pathological processes in CNS.
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Identification of ionotrophic purinergic receptors in Huh-7 cells and their response towards structural proteins of HCV genotype 3a. Virol J 2011; 8:431. [PMID: 21899776 PMCID: PMC3177911 DOI: 10.1186/1743-422x-8-431] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2011] [Accepted: 09/08/2011] [Indexed: 01/13/2023] Open
Abstract
Hepatitis C virus (HCV) is a major health problem in developing countries including Pakistan. Chronic HCV infection results in progressive liver disease including fibrosis, cirrhosis, insulin resistance and eventually hepatocellular carcinoma (HCC). Ionotrophic purinergic (P2X) receptors are identified to involve in a spectrum of physiological and pathophysiological processes. However, the role of P2X receptors in HCV liver associated diseases still remains to be investigated. The current study was designed to identify the presence of P2X receptors in human liver cells. Furthermore, it investigates the response of P2X receptors towards HCV structural proteins (E1E2). To determine that how many isoforms of P2X receptors are expressed in human liver cells, human hepatoma cell line (Huh-7) was used. Transcripts (mRNA) of five different isoforms of P2X receptors were identified in Huh-7 cells. To examine the gene expression of identified isoforms of P2X receptors in presence of HCV structural proteins E1E2, Huh-7/E1E2 cell line (stably expressing HCV structural proteins E1E2) was used. The results showed significant increase (6.2 fold) in gene expression of P2X4 receptors in Huh-7/E1E2 cells as compared to control Huh-7 cells. The findings of present study confirmed the presence of transcripts of five different isoforms of P2X receptors in human liver cells and suggest that P2X4 receptors could be represented an important component of the purinergic signaling complex in HCV induced liver pathogenesis.
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Bauerle JD, Grenz A, Kim JH, Lee HT, Eltzschig HK. Adenosine generation and signaling during acute kidney injury. J Am Soc Nephrol 2011; 22:14-20. [PMID: 21209250 DOI: 10.1681/asn.2009121217] [Citation(s) in RCA: 104] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Acute kidney injury (AKI) is among the leading causes of morbidity and mortality in hospitalized patients. Particularly in the perioperative period, the most common cause of AKI is renal ischemia. At present, therapeutic modalities to prevent or treat AKI are extremely limited and the search for novel therapeutic interventions for ischemic AKI is an area of intense investigation. Recent studies implicate the endogenous signaling molecule, adenosine, in kidney protection from ischemia. As such, enzymatic production of adenosine from its precursor molecules ATP and AMP, and signaling events through adenosine receptors, play a critical role in attenuating renal inflammation and preserving kidney function during episodes of renal ischemia. Utilizing genetic mouse models with defects in adenosine generation or signaling provide strong evidence for the key role of extracellular adenosine in adapting renal tissues to limited oxygen availability and attenuating hypoxia-driven inflammation of the kidneys. Moreover, experimental therapeutics targeting individual adenosine receptors demonstrate strong prophylactic or therapeutic effects during murine AKI. If these experimental strategies can be translated into a clinical setting, adenosine receptor therapeutics may become an integral part in the prevention or treatment of AKI from renal ischemia.
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Affiliation(s)
- Jessica D Bauerle
- Mucosal Inflammation Program, Department of Anesthesiology, University of Colorado Denver, 12700 E 19 Avenue, Mailstop B112, Research Complex 2, Room 7124, Aurora, CO 80045, USA
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Novak I, Jans IM, Wohlfahrt L. Effect of P2X(7) receptor knockout on exocrine secretion of pancreas, salivary glands and lacrimal glands. J Physiol 2010; 588:3615-27. [PMID: 20643770 DOI: 10.1113/jphysiol.2010.190017] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The purinergic P2X(7) receptors are expressed in different cell types where they have varied functions, including regulation of cell survival. The P2X(7) receptors are also expressed in exocrine glands, but their integrated role in secretion is unclear. The aim of our study was to determine whether the P2X(7) receptors affect fluid secretion in pancreas, salivary glands and tear glands. We monitored gland secretions in in vivo preparations of wild-type and P2X(7)(-/-) (Pfizer) mice stimulated with pilocarpine. In cell preparations from pancreas, parotid and lacrimal glands we measured ATP release and intracellular Ca(2+) activity using Fura-2. The data showed that pancreatic secretion and salivary secretions were reduced in P2X(7)(-/-) mice, and in contrast, tear secretion was increased in P2X(7)(-/-) mice. The secretory phenotype was also dependent on the sex of the animal, such that males were more dependent on the P2X(7) receptor expression. ATP release in all cell preparations could be elicited by carbachol and other agonists, and this was independent of the P2X(7) receptor expression. ATP and carbachol increased intracellular Ca(2+) activity, but responses depended on the gland type, presence of the P2X(7) receptor and the sex of the animal. Together, these results demonstrate that cholinergic stimulation leads to release of ATP that can via P2X(7) receptors up-regulate pancreatic and salivary secretion but down-regulate tear secretion. Our data also indicate that there is an interaction between purinergic and cholinergic receptor signalling and that function of the P2X(7) receptor is suppressed in females. We conclude that the P2X(7) receptors are important in short-term physiological regulation of exocrine gland secretion.
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Affiliation(s)
- Ivana Novak
- Department of Biology, August Krogh Building, Universitetsparken 13, University of Copenhagen, DK 2100 Copenhagen Ø, Denmark.
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Extracellular ATP and P2Y2 receptors mediate intercellular Ca(2+) waves induced by mechanical stimulation in submandibular gland cells: Role of mitochondrial regulation of store operated Ca(2+) entry. Cell Calcium 2010; 47:65-76. [PMID: 20022109 DOI: 10.1016/j.ceca.2009.11.006] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2009] [Revised: 11/13/2009] [Accepted: 11/17/2009] [Indexed: 12/29/2022]
Abstract
Coordination of Ca(2+) signaling among cells contributes to synchronization of salivary gland cell function. However, mechanisms that underlie this signaling remain elusive. Here, intercellular Ca(2+) waves (ICW) in submandibular gland cells were investigated using Fura-2 fluorescence imaging. Mechanical stimulation of single cells induced ICW propagation from the stimulated cells through approximately 7 layers of cells or approximately 120microm. Our findings indicate that an extracellular ATP-dependent pathway is involved because the purinergic receptor antagonist suramin and the ATP hydrolyzing enzyme apyrase blocked ICW propagation. However, the gap junction uncoupler oleamide had no effect. ATP is released from mechanically stimulated cells possibly through opening of mechanosensitive maxi-anion channels, and does not appear to be directly linked to cytosolic Ca(2+). The ICW is propagated by diffusing ATP, which activates purinergic receptors in neighboring cells. This purinergic signaling induces a Ca(2+) transient that is dependent on Ca(2+) release via IP(3) receptors in the ER and store operated Ca(2+) entry (SOCE). Finally, inhibition of mitochondrial Ca(2+) uptake modified ICW indicating an important role of these organelles in this phenomenon. These studies increase our understanding of purinergic receptor signaling in salivary gland cells, and its role as a coordination mechanism of Ca(2+) signals induced by mechanical stimulation.
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P2 receptor-mediated signaling in mast cell biology. Purinergic Signal 2009; 6:3-17. [PMID: 19921464 DOI: 10.1007/s11302-009-9173-z] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2009] [Accepted: 10/23/2009] [Indexed: 12/22/2022] Open
Abstract
Mast cells are widely recognized as effector cells of allergic inflammatory reactions. They contribute to the pathogenesis of different chronic inflammatory diseases, wound healing, fibrosis, thrombosis/fibrinolysis, and anti-tumor immune responses. In this paper, we summarized the role of P2X and P2Y receptors in mast cell activation and effector functions. Mast cells are an abundant source of ATP which is stored in their granules and secreted upon activation. We discuss the contribution of mast cells to the extracellular ATP release and to the maintenance of extracellular nucleotides pool. Recent publications highlight the importance of purinergic signaling for the pathogenesis of chronic airway inflammation. Therefore, the role of ATP and P2 receptors in allergic inflammation with focus on mast cells was analyzed. Finally, ATP functions as mast cell autocrine/paracrine factor and as messenger in intercellular communication between mast cells, nerves, and glia in the central nervous system.
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Hwang SM, Li J, Koo NY, Choi SY, Lee SJ, Oh SB, Castro R, Kim JS, Park K. Role of purinergic receptor in alpha fodrin degradation in Par C5 cells. J Dent Res 2009; 88:927-32. [PMID: 19783801 DOI: 10.1177/0022034509342227] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Autoantibodies specific for alpha-fodrin fragments are found in the tissues of persons afflicted with Sjögren's syndrome (SS). However, the mechanism for alpha-fodrin degradation remains elusive. The following experiments utilized Par C5 cells to examine the role of P2X7 receptor (P2X7R) in apoptosis, particularly in the cleavage and release of alpha-fodrin, an apparent SS autoantigen. Five mM ATP stimulation induced apoptotic cell death with a sustained Ca2+ influx, which was mimicked in HEK cells transfected with P2X7R. ATP also induced cleavage of alpha-fodrin mediated by caspase-3 and calpain, releasing alpha-fodrin fragments through membrane blebs. However, both apoptotic cell death and alpha-fodrin cleavage were inhibited in the presence of 300 microM oxidized-ATP (ox-ATP), an irreversible blocker of P2X7R, or in Ca(2+)-free solution. We concluded that P2X7R plays an important role in apoptosis and alpha-fodrin degradation in salivary epithelial cells, providing an important clue elucidating the presence of alpha-fodrin fragments in SS tissues.
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Affiliation(s)
- S-M Hwang
- Department of Physiology, School of Dentistry, Seoul National University and Dental Research Institute, Yeongeon Dong 28, Chongno Ku, Seoul 110-749, Korea
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Hwang SM, Koo NY, Choi SY, Chun GS, Kim JS, Park K. P2X7 Receptor-mediated Membrane Blebbing in Salivary Epithelial Cells. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2009; 13:175-9. [PMID: 19885034 DOI: 10.4196/kjpp.2009.13.3.175] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2009] [Revised: 05/06/2009] [Accepted: 05/18/2009] [Indexed: 11/15/2022]
Abstract
High concentrations of ATP induce membrane blebbing. However, the underlying mechanism involved in epithelial cells remains unclear. In this study, we investigated the role of the P2X7 receptor (P2X7R) in membrane blebbing using Par C5 cells. We stimulated the cells with 5 mM of ATP for 1~2 hrs and found the characteristics of membrane blebbing, a hallmark of apoptotic cell death. In addition, 500 microM Bz-ATP, a specific P2X7R agonist, induced membrane blebbing. However, 300 microM of Ox-ATP, a P2X7R antagonist, inhibited ATP-induced membrane blebbing, suggesting that ATP-induced membrane blebbing is mediated by P2X7R. We found that ATP-induced membrane blebbing was mediated by ROCK I activation and MLC phosphorylation, but not by caspase-3. Five mM of ATP evoked a biphasic [Ca(2+)](i) response; a transient [Ca(2+)](i) peak and sustained [Ca(2+)](i) increase secondary to ATP-stimulated Ca(2+) influx. These results suggest that P2X7R plays a role in membrane blebbing of the salivary gland epithelial cells.
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Affiliation(s)
- Sung-Min Hwang
- Department of Physiology, School of Dentistry, Seoul National University and Dental Research Institute, Seoul 110-749, Korea
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Praetorius HA, Leipziger J. ATP release from non-excitable cells. Purinergic Signal 2009; 5:433-46. [PMID: 19301146 DOI: 10.1007/s11302-009-9146-2] [Citation(s) in RCA: 181] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2007] [Accepted: 03/03/2008] [Indexed: 02/06/2023] Open
Abstract
All cells release nucleotides and are in one way or another involved in local autocrine and paracrine regulation of organ function via stimulation of purinergic receptors. Significant technical advances have been made in recent years to quantify more precisely resting and stimulated adenosine triphosphate (ATP) concentrations in close proximity to the plasma membrane. These technical advances are reviewed here. However, the mechanisms by which cells release ATP continue to be enigmatic. The current state of knowledge on different suggested mechanisms is also reviewed. Current evidence suggests that two separate regulated modes of ATP release co-exist in non-excitable cells: (1) a conductive pore which in several systems has been found to be the channel pannexin 1 and (2) vesicular release. Modes of stimulation of ATP release are reviewed and indicate that both subtle mechanical stimulation and agonist-triggered release play pivotal roles. The mechano-sensor for ATP release is not yet defined.
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Affiliation(s)
- Helle A Praetorius
- Department of Physiology and Biophysics, Aarhus University, Ole Worms Alle 160, 8000, Aarhus, Denmark
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Novak I, Haanes KA, Hansen MR, Krabbe S, Hede SE. Extracellular purinergic signaling in pancreas. THE JOURNAL OF MEDICAL INVESTIGATION 2009; 56 Suppl:355-6. [PMID: 20224224 DOI: 10.2152/jmi.56.355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Ivana Novak
- Department of Biology, August Krogh Building, University of Copenhagen, Copenhagen, Denmark
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Nakamoto T, Brown DA, Catalán MA, Gonzalez-Begne M, Romanenko VG, Melvin JE. Purinergic P2X7 receptors mediate ATP-induced saliva secretion by the mouse submandibular gland. J Biol Chem 2008; 284:4815-22. [PMID: 19097994 DOI: 10.1074/jbc.m808597200] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Salivary glands express multiple isoforms of P2X and P2Y nucleotide receptors, but their in vivo physiological roles are unclear. P2 receptor agonists induced salivation in an ex vivo submandibular gland preparation. The nucleotide selectivity sequence of the secretion response was BzATP >> ATP > ADP >> UTP, and removal of external Ca(2+) dramatically suppressed the initial ATP-induced fluid secretion ( approximately 85%). Together, these results suggested that P2X receptors are the major purinergic receptor subfamily involved in the fluid secretion process. Mice with targeted disruption of the P2X(7) gene were used to evaluate the role of the P2X(7) receptor in nucleotide-evoked fluid secretion. P2X(7) receptor protein and BzATP-activated inward cation currents were absent, and importantly, purinergic receptor agonist-stimulated salivation was suppressed by more than 70% in submandibular glands from P2X(7)-null mice. Consistent with these observations, the ATP-induced increases in [Ca(2+)](i) were nearly abolished in P2X(7)(-/-) submandibular acinar and duct cells. ATP appeared to also act through the P2X(7) receptor to inhibit muscarinic-induced fluid secretion. These results demonstrate that the ATP-sensitive P2X(7) receptor regulates fluid secretion in the mouse submandibular gland.
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Affiliation(s)
- Tetsuji Nakamoto
- Center for Oral Biology, University of Rochester Medical Center, Rochester, New York 14642, USA
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Weissmüller T, Campbell EL, Rosenberger P, Scully M, Beck PL, Furuta GT, Colgan SP. PMNs facilitate translocation of platelets across human and mouse epithelium and together alter fluid homeostasis via epithelial cell-expressed ecto-NTPDases. J Clin Invest 2008; 118:3682-92. [PMID: 18924612 DOI: 10.1172/jci35874] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2008] [Accepted: 09/03/2008] [Indexed: 02/03/2023] Open
Abstract
Mucosal diseases are often characterized by an inflammatory infiltrate that includes polymorphonuclear leukocytes (PMNs), monocytes, lymphocytes, and platelets. A number of studies have suggested that the interaction of platelets with leukocytes has an essential proinflammatory role. Here, we examined whether platelets migrate across mucosal epithelium, as PMNs are known to do, and whether platelets influence epithelial cell function. Initial studies revealed that human platelets did not efficiently transmigrate across human epithelial cell monolayers. However, in the presence of human PMNs, platelet movement across the epithelium was proportional to the extent of PMN transmigration, and strategies that blocked PMN transmigration diminished platelet movement. Furthermore, platelet-PMN comigration was observed in intestinal tissue derived from human patients with inflammatory bowel disease (IBD). The translocated platelets were found to release large quantities of ATP, which was metabolized to adenosine via a 2-step enzymatic reaction mediated by ecto-nucleotidases, including CD73 and ecto-nucleoside triphosphate diphosphohydrolases (ecto-NTPDases), expressed on the apical membrane of the intestinal epithelial cells. In vitro studies and a mouse model of intestinal inflammation were employed to define a mechanism involving adenosine-mediated induction of electrogenic chloride secretion, with concomitant water movement into the intestinal lumen. These studies demonstrate that ecto-NTPDases are expressed on the apical membrane of epithelial cells and are involved in what we believe to be a previously unappreciated function for platelets in the inflamed intestine, which might promote bacterial clearance under inflammatory conditions.
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Affiliation(s)
- Thomas Weissmüller
- Division of Gastroenterology, University of Colorado Denver School of Medicine, Aurora, Colorado, USA
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