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Al-Aqtash R, Collier DM. Ionotropic purinergic receptor 7 (P2X7) channel structure and pharmacology provides insight regarding non-nucleotide agonism. Channels (Austin) 2024; 18:2355150. [PMID: 38762911 PMCID: PMC11110710 DOI: 10.1080/19336950.2024.2355150] [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: 04/01/2024] [Accepted: 05/10/2024] [Indexed: 05/21/2024] Open
Abstract
P2X7 is a member of the Ionotropic Purinergic Receptor (P2X) family. The P2X family of receptors is composed of seven (P2X1-7), ligand-gated, nonselective cation channels. Changes in P2X expression have been reported in multiple disease models. P2Xs have large complex extracellular domains that function as receptors for a variety of ligands, including endogenous and synthetic agonists and antagonists. ATP is the canonical agonist. ATP affinity ranges from nanomolar to micromolar for most P2XRs, but P2X7 has uniquely poor ATP affinity. In many physiological settings, it may be difficult to achieve the millimolar extracellular ATP concentrations needed for P2X7 channel activation; however, channel function is implicated in pain sensation, immune cell function, cardiovascular disease, cancer, and osteoporosis. Multiple high-resolution P2X7 structures have been solved in apo-, ATP-, and antagonist-bound states. P2X7 structural data reveal distinct allosteric and orthosteric antagonist-binding sites. Both allosteric and orthosteric P2X7 antagonists are well documented to inhibit ATP-evoked channel current. However, a growing body of evidence supports P2X7 activation by non-nucleotide agonists, including extracellular histone proteins and human cathelicidin-derived peptides (LL-37). Interestingly, P2X7 non-nucleotide agonism is not inhibited by allosteric antagonists, but is inhibited by orthosteric antagonists. Herein, we review P2X7 function with a focus on the efficacy of available pharmacology on P2X7 channel current activation by non-nucleotide agonists in effort to understand agonist/antagonist efficacy, and consider the impact of these data on the current understanding of P2X7 in physiology and disease given these limitations of P2X7-selective antagonists and incomplete knockout mouse models.
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Affiliation(s)
- Rua’a Al-Aqtash
- Department of Pharmaceutical Sciences, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Daniel M. Collier
- Department of Pharmaceutical Sciences, University of Tennessee Health Science Center, Memphis, TN, USA
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2
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Leite-Aguiar R, Bello-Santos VG, Castro NG, Coutinho-Silva R, Savio LEB. Techniques for evaluating the ATP-gated ion channel P2X7 receptor function in macrophages and microglial cells. J Immunol Methods 2024; 532:113727. [PMID: 38997100 DOI: 10.1016/j.jim.2024.113727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Revised: 05/31/2024] [Accepted: 07/08/2024] [Indexed: 07/14/2024]
Abstract
Resident macrophages are tissue-specific innate immune cells acting as sentinels, constantly patrolling their assigned tissue to maintain homeostasis, and quickly responding to pathogenic invaders or molecular danger signals molecules when necessary. Adenosine triphosphate (ATP), when released to the extracellular medium, acts as a danger signal through specific purinergic receptors. Interaction of ATP with the purinergic receptor P2X7 activates macrophages and microglial cells in different pathological conditions, triggering inflammation. The highly expressed P2X7 receptor in these cells induces cell membrane permeabilization, inflammasome activation, cell death, and the production of inflammatory mediators, including cytokines and nitrogen and oxygen-reactive species. This review explores the techniques to evaluate the functional and molecular aspects of the P2X7 receptor, particularly in macrophages and microglial cells. Polymerase chain reaction (PCR), Western blotting, and immunocytochemistry or immunohistochemistry are essential for assessing gene and protein expression in these cell types. Evaluation of P2X7 receptor function involves the use of ATP and selective agonists and antagonists and diverse techniques, including electrophysiology, intracellular calcium measurements, ethidium bromide uptake, and propidium iodide cell viability assays. These techniques are crucial for studying the role of P2X7 receptors in immune responses, neuroinflammation, and various pathological conditions. Therefore, a comprehensive understanding of the functional and molecular aspects of the P2X7 receptor in macrophages and microglia is vital for unraveling its involvement in immune modulation and its potential as a therapeutic target. The methodologies presented and discussed herein offer valuable tools for researchers investigating the complexities of P2X7 receptor signaling in innate immune cells in health and disease.
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Affiliation(s)
- Raíssa Leite-Aguiar
- Laboratório de Imunofisiologia, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | | | | | - Robson Coutinho-Silva
- Laboratório de Imunofisiologia, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Luiz Eduardo Baggio Savio
- Laboratório de Imunofisiologia, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil..
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3
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Torres-Rico M, García-Calvo V, Gironda-Martínez A, Pascual-Guerra J, García AG, Maneu V. Targeting calciumopathy for neuroprotection: focus on calcium channels Cav1, Orai1 and P2X7. Cell Calcium 2024; 123:102928. [PMID: 39003871 DOI: 10.1016/j.ceca.2024.102928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2024] [Revised: 07/02/2024] [Accepted: 07/05/2024] [Indexed: 07/16/2024]
Abstract
As the uncontrolled entry of calcium ions (Ca2+) through plasmalemmal calcium channels is a cell death trigger, the conjecture is here raised that mitigating such an excess of Ca2+ entry should rescue from death the vulnerable neurons in neurodegenerative diseases (NDDs). However, this supposition has failed in some clinical trials (CTs). Thus, a recent CT tested whether isradipine, a blocker of the Cav1 subtype of voltage-operated calcium channels (VOCCs), exerted a benefit in patients with Parkinson's disease (PD); however, outcomes were negative. This is one more of the hundreds of CTs done under the principle of one-drug-one-target, that have failed in Alzheimer's disease (AD) and other NDDs during the last three decades. As there are myriad calcium channels to let Ca2+ ions gain the cell cytosol, it seems reasonable to predict that blockade of Ca2+ entry through a single channel may not be capable of preventing the Ca2+ flood of cells by the uncontrolled Ca2+ entry. Furthermore, as Ca2+ signaling is involved in the regulation of myriad functions in different cell types, it seems also reasonable to guess that a therapy should be more efficient by targeting different cells with various drugs. Here, we propose to mitigate Ca2+ entry by the simultaneous partial blockade of three quite different subtypes of plasmalemmal calcium channels that is, the Cav1 subtype of VOCCs, the Orai1 store-operated calcium channel (SOCC), and the purinergic P2X7 calcium channel. All three channels are expressed in both microglia and neurons. Thus, by targeting the three channels with a combination of three drug blockers we expect favorable changes in some of the pathogenic features of NDDs, namely (i) to mitigate Ca2+ entry into microglia; (ii) to decrease the Ca2+-dependent microglia activation; (iii) to decrease the sustained neuroinflammation; (iv) to decrease the uncontrolled Ca2+ entry into neurons; (v) to rescue vulnerable neurons from death; and (vi) to delay disease progression. In this review we discuss the arguments underlying our triad hypothesis in the sense that the combination of three repositioned medicines targeting Cav1, Orai1, and P2X7 calcium channels could boost neuroprotection and delay the progression of AD and other NDDs.
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Affiliation(s)
| | | | - Adrián Gironda-Martínez
- Instituto Fundación Teófilo Hernando, Madrid, Spain; Departamento de Farmacología y Terapéutica, Universidad Autónoma de Madrid, Madrid, Spain
| | | | - Antonio G García
- Instituto Fundación Teófilo Hernando, Madrid, Spain; Departamento de Farmacología y Terapéutica, Universidad Autónoma de Madrid, Madrid, Spain; Facultad de Medicina, Instituto de Investigación Sanitaria del Hospital Universitario La Princesa, Universidad Autónoma de Madrid, Madrid, Spain.
| | - Victoria Maneu
- Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante, Alicante, Spain.
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4
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Fortuny-Gomez A, Fountain SJ. Pharmacological differences between human and mouse P2X4 receptor explored using old and new tools. Purinergic Signal 2024:10.1007/s11302-024-10018-x. [PMID: 38767821 DOI: 10.1007/s11302-024-10018-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Accepted: 05/08/2024] [Indexed: 05/22/2024] Open
Abstract
There is growing interest in the P2X4 receptor as a therapeutic target for several cardiovascular, inflammatory and neurological conditions. Key to exploring the physiological and pathophysiological roles of P2X4 is access to selective compounds to probe function in cells, tissues and animal models. There has been a recent growth in selective antagonists for P2X4, though agonist selectivity is less well studied. As there are some known pharmacological differences between P2X receptors from different species, it is important to understand these differences when designing a pharmacological strategy to probe P2X4 function in human tissue and mouse models. Here, we provide a systematic comparison of agonist and antagonist pharmacology in 1321N1 cells expressing either human or mouse P2X4 orthologues. We identify a rank order of agonist potency of ATP > 2-MeSATP > αβmeATP = BzATP > CTP = γ-[(propargyl)-imido]-ATP for human P2X4 and ATP > 2-MeSATP = CTP > ATPγS = γ-[(propargyl)-imido]-ATP = BzATP for mouse. Human P2X4 is not activated by ATPγS but can be activated by αβmeATP. We identify a rank order of antagonist potency of BAY-1797 = PSB-12062 = BX-430 > 5-BDBD > TNP-ATP = PPADS for human P2X4 and BAY-1797 > PSB-12062 = PPADS > TNP-ATP for mouse. Mouse P2X4 is not antagonised by 5-BDBD or BX-430. The study reveals key pharmacological differences between human and mouse P2X4, highlighting caution when selecting tools for comparative studies between human and mouse and ascribing cellular responses of some commonly used agonists to P2X4.
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Affiliation(s)
- Anna Fortuny-Gomez
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, UK
| | - Samuel J Fountain
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, UK.
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Gardner EC, Tramont C, Bachanová P, Wang C, Do H, Boutz DR, Kar S, Zemelman BV, Gollihar JD, Ellington AD. Engineering a human P2X2 receptor with altered ligand selectivity in yeast. J Biol Chem 2024; 300:107248. [PMID: 38556082 PMCID: PMC11063903 DOI: 10.1016/j.jbc.2024.107248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Revised: 03/14/2024] [Accepted: 03/23/2024] [Indexed: 04/02/2024] Open
Abstract
P2X receptors are a family of ligand gated ion channels found in a range of eukaryotic species including humans but are not naturally present in the yeast Saccharomyces cerevisiae. We demonstrate the first recombinant expression and functional gating of the P2X2 receptor in baker's yeast. We leverage the yeast host for facile genetic screens of mutant P2X2 by performing site saturation mutagenesis at residues of interest, including SNPs implicated in deafness and at residues involved in native binding. Deep mutational analysis and rounds of genetic engineering yield mutant P2X2 F303Y A304W, which has altered ligand selectivity toward the ATP analog AMP-PNP. The F303Y A304W variant shows over 100-fold increased intracellular calcium amplitudes with AMP-PNP compared to the WT receptor and has a much lower desensitization rate. Since AMP-PNP does not naturally activate P2X receptors, the F303Y A304W P2X2 may be a starting point for downstream applications in chemogenetic cellular control. Interestingly, the A304W mutation selectively destabilizes the desensitized state, which may provide a mechanistic basis for receptor opening with suboptimal agonists. The yeast system represents an inexpensive, scalable platform for ion channel characterization and engineering by circumventing the more expensive and time-consuming methodologies involving mammalian hosts.
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Affiliation(s)
- Elizabeth C Gardner
- Department of Molecular Biosciences, Center for Systems and Synthetic Biology, The University of Texas at Austin, Austin, Texas, USA
| | - Caitlin Tramont
- Department of Molecular Biosciences, Center for Systems and Synthetic Biology, The University of Texas at Austin, Austin, Texas, USA
| | - Petra Bachanová
- Department of Molecular Biosciences, Center for Systems and Synthetic Biology, The University of Texas at Austin, Austin, Texas, USA
| | - Chad Wang
- Department of Molecular Biosciences, Center for Systems and Synthetic Biology, The University of Texas at Austin, Austin, Texas, USA
| | - Hannah Do
- Department of Molecular Biosciences, Center for Systems and Synthetic Biology, The University of Texas at Austin, Austin, Texas, USA
| | - Daniel R Boutz
- Antibody Discovery and Accelerated Protein Therapeutics, Department of Pathology & Genomic Medicine, Houston Methodist Research Institute, Houston, Texas, USA
| | - Shaunak Kar
- Antibody Discovery and Accelerated Protein Therapeutics, Department of Pathology & Genomic Medicine, Houston Methodist Research Institute, Houston, Texas, USA
| | - Boris V Zemelman
- Department of Neuroscience, Center for Learning and Memory, The University of Texas at Austin, Austin, Texas, USA.
| | - Jimmy D Gollihar
- Antibody Discovery and Accelerated Protein Therapeutics, Department of Pathology & Genomic Medicine, Houston Methodist Research Institute, Houston, Texas, USA.
| | - Andrew D Ellington
- Department of Molecular Biosciences, Center for Systems and Synthetic Biology, The University of Texas at Austin, Austin, Texas, USA.
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6
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Benson LN, Deck KS, Mora CJ, Guo Y, Rafferty TM, Li LX, Huang L, Andrews JT, Qin Z, Trott DW, Hoover RS, Liu Y, Mu S. P2X7-Mediated Antigen-Independent Activation of CD8 + T Cells Promotes Salt-Sensitive Hypertension. Hypertension 2024; 81:530-540. [PMID: 38193292 PMCID: PMC10922507 DOI: 10.1161/hypertensionaha.123.21819] [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: 07/17/2023] [Accepted: 12/27/2023] [Indexed: 01/10/2024]
Abstract
BACKGROUND CD8+ T cells (CD8Ts) have been implicated in hypertension. However, the specific mechanisms are not fully understood. In this study, we explore the contribution of the P2X7 (purinergic receptor P2X7) receptor to CD8T activation and subsequent promotion of sodium retention in the kidney. METHODS We used mouse models of hypertension. Wild type were used as genetic controls, OT1 and Rag2/OT1 mice were utilized to determine antigen dependency, and P2X7-knockout mice were studied to define the role of P2X7 in activating CD8Ts and promoting hypertension. Blood pressure was monitored continuously and kidneys were obtained at different experimental end points. Freshly isolated CD8Ts from mice for activation assays and ATP stimulation. CD8T activation-induced promotion of sodium retention was explored in cocultures of CD8Ts and mouse DCTs. RESULTS We found that OT1 and Rag2/OT1 mice, which are nonresponsive to common antigens, still developed hypertension and CD8T-activation in response to deoxycorticosterone acetate/salt treatment, similar to wild-type mice. Further studies identified the P2X7 receptor on CD8Ts as a possible mediator of this antigen-independent activation of CD8Ts in hypertension. Knockout of the P2X7 receptor prevented calcium influx and cytokine production in CD8Ts. This finding was associated with reduced CD8T-DCT stimulation, reversal of excessive salt retention in DCTs, and attenuated development of salt-sensitive hypertension. CONCLUSIONS Our findings suggest a novel mechanism by which CD8Ts are activated in hypertension to exacerbate salt retention and infer that the P2X7 receptor on CD8Ts may represent a new therapeutic target to attenuate T-cell-mediated immunopathology in hypertension.
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Affiliation(s)
| | | | | | | | | | - Lin-Xi Li
- Department of Microbiology and Immunology
| | - Lu Huang
- Department of Microbiology and Immunology
| | | | - Zhiqiang Qin
- Department of Pathology, University of Arkansas for Medical Sciences, Little Rock, AR 72205
| | - Daniel W. Trott
- Department of Kinesiology, University of Texas at Arlington, Arlington, TX 76019
| | - Robert S. Hoover
- Department of Medicine, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | | | - Shengyu Mu
- Department of Pharmacology and Toxicology
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7
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Sluyter R, McEwan TBD, Sophocleous RA, Stokes L. Methods for studying P2X4 receptor ion channels in immune cells. J Immunol Methods 2024; 526:113626. [PMID: 38311008 DOI: 10.1016/j.jim.2024.113626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Revised: 01/28/2024] [Accepted: 02/01/2024] [Indexed: 02/06/2024]
Abstract
The P2X4 receptor is a trimeric ligand-gated ion channel activated by adenosine 5'-triphosphate (ATP). P2X4 is present in immune cells with emerging roles in inflammation and immunity, and related disorders. This review aims to provide an overview of the methods commonly used to study P2X4 in immune cells, focusing on those methods used to assess P2RX4 gene expression, the presence of the P2X4 protein, and P2X4 ion channel activity in these cells from humans, dogs, mice and rats. P2RX4 gene expression in immune cells is commonly assessed using semi-quantitative and quantitative reverse-transcriptase-PCR. The presence of P2X4 protein in immune cells is mainly assessed using anti-P2X4 polyclonal antibodies with immunoblotting or immunochemistry, but the use of these antibodies, as well as monoclonal antibodies and nanobodies to detect P2X4 with flow cytometry is increasing. Notably, use of an anti-P2X4 monoclonal antibody and flow cytometry has revealed that P2X4 is present on immune cells with a rank order of expression in eosinophils, then neutrophils and monocytes, then basophils and B cells, and finally T cells. P2X4 ion channel activity has been assessed mainly by Ca2+ flux assays using the cell permeable Ca2+-sensitive dyes Fura-2 and Fluo-4 with fluorescence microscopy, spectrophotometry, or flow cytometry. However, other methods including electrophysiology, and fluorescence assays measuring Na+ flux (using sodium green tetra-acetate) and dye uptake (using YO-PRO-12+) have been applied. Collectively, these methods have demonstrated the presence of functional P2X4 in monocytes and macrophages, microglia, eosinophils, mast cells and CD4+ T cells, with other evidence suggestive of functional P2X4 in dendritic cells, neutrophils, B cells and CD8+ T cells.
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Affiliation(s)
- Ronald Sluyter
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia.
| | - Tahnee B-D McEwan
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia
| | - Reece A Sophocleous
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia
| | - Leanne Stokes
- School of Pharmacy, University of East Anglia, Norwich, Norfolk NR4 7TJ, UK
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Fukuyama K, Motomura E, Okada M. Age-Dependent Activation of Purinergic Transmission Contributes to the Development of Epileptogenesis in ADSHE Model Rats. Biomolecules 2024; 14:204. [PMID: 38397441 PMCID: PMC10886636 DOI: 10.3390/biom14020204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 02/05/2024] [Accepted: 02/06/2024] [Indexed: 02/25/2024] Open
Abstract
To explore the developmental processes of epileptogenesis/ictogenesis, this study determined age-dependent functional abnormalities associated with purinergic transmission in a genetic rat model (S286L-TG) of autosomal-dominant sleep-related hypermotor epilepsy (ADSHE). The age-dependent fluctuations in the release of ATP and L-glutamate in the orbitofrontal cortex (OFC) were determined using microdialysis and ultra-high-performance liquid chromatography with mass spectrometry (UHPLC-MS). ATP release from cultured astrocytes was also determined using UHPLC-MS. The expressions of P2X7 receptor (P2X7R), connexin 43, phosphorylated-Akt and phosphorylated-Erk were determined using capillary immunoblotting. No functional abnormalities associated with purinergic transmission could be detected in the OFC of 4-week-old S286L-TG and cultured S286L-TG astrocytes. However, P2X7R expression, as well as basal and P2X7R agonist-induced ATP releases, was enhanced in S286L-TG OFC in the critical ADSHE seizure onset period (7-week-old). Long-term exposure to a modest level of P2X7R agonist, which could not increase astroglial ATP release, for 14 d increased the expressions of P2X7R and connexin 43 and the signaling of Akt and Erk in astrocytes, and it enhanced the sensitivity of P2X7R to its agonists. Akt but not Erk increased P2X7R expression, whereas both Akt and Erk increased connexin 43 expression. Functional abnormalities, enhanced ATP release and P2X7R expression were already seen before the onset of ADSHE seizure in S286L-TG. Additionally, long-term exposure to the P2X7R agonist mimicked the functional abnormalities associated with purinergic transmission in astrocytes, similar to those in S286L-TG OFC. Therefore, these results suggest that long-term modestly enhanced purinergic transmission and/or activated P2X7R are, at least partially, involved in the development of the epileptogenesis of ADSHE, rather than that of ictogenesis.
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Affiliation(s)
| | | | - Motohiro Okada
- Department of Neuropsychiatry, Division of Neuroscience, Graduate School of Medicine, Mie University, Tsu 514-8507, Japan; (K.F.); (E.M.)
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Ding L, Qian J, Yu X, Wu Q, Mao J, Liu X, Wang Y, Guo D, Su R, Xie H, Yin S, Zhou L, Zheng S. Blocking MARCO + tumor-associated macrophages improves anti-PD-L1 therapy of hepatocellular carcinoma by promoting the activation of STING-IFN type I pathway. Cancer Lett 2024; 582:216568. [PMID: 38065400 DOI: 10.1016/j.canlet.2023.216568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 11/16/2023] [Accepted: 11/27/2023] [Indexed: 12/24/2023]
Abstract
The PD-L1/PD-1 axis is a classic immunotherapy target. However, anti-PD-L1/PD-1 therapy alone can not achieve satisfactory results in solid tumors, especially liver cancer. Among the several factors involved in tumor anti-PD-L1/PD-1 treatment resistance, tumor-associated macrophages (TAMs) have attracted attention because of their immunosuppressive ability. TAMs with a macrophage receptor with a collagenous structure (MARCO) are a macrophage subset group with strong immunosuppressive abilities. Clinical specimens and animal experiments revealed a negative correlation between MARCO + TAMs and patient prognosis with liver cancer. Transcriptional data and in vitro and in vivo experiments revealed that MARCO + TAM immunosuppressive ability was related to secretion. MARCO suppressed IFN-β secretion from TAMs, reducing antigen presentation molecule expression, infiltration, and CD8+T cell dysfunction, thus producing an immunosuppressive microenvironment in liver cancer. MARCO can promote dying tumor cell clearance by macrophages, reducing tumor-derived cGAMP and ATP accumulation in the tumor microenvironment and inhibiting sting-IFN-β pathway activation mediated by P2X7R in MARCO+TAMs. Animal experiments revealed that the MARCO and PD-L1 monoclonal antibody combination could significantly inhibit liver cancer growth. Conclusively, targeting MARCO+TAMs can significantly improve anti-PD-L1 resistance in liver cancer, making it a potential novel immune target for liver cancer therapy.
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Affiliation(s)
- Limin Ding
- Division of Hepatobiliary and Pancreatic Surgery, Department of Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310003, China; NHC Key Laboratory of Combined Multi-organ Transplantation, Hangzhou, 310003, China; Key Laboratory of the Diagnosis and Treatment of Organ Transplantation, Research Unit of Collaborative Diagnosis and Treatment for Hepatobiliary and Pancreatic Cancer, Chinese Academy of Medical Sciences(2019RU019), Hangzhou, 310003, China; Key Laboratory of Organ Transplantation, Research Center for Diagnosis and Treatment of Hepatobiliary Diseases, Zhejiang Province, Hangzhou, 310003, China
| | - Junjie Qian
- Division of Hepatobiliary and Pancreatic Surgery, Department of Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310003, China; NHC Key Laboratory of Combined Multi-organ Transplantation, Hangzhou, 310003, China; Key Laboratory of the Diagnosis and Treatment of Organ Transplantation, Research Unit of Collaborative Diagnosis and Treatment for Hepatobiliary and Pancreatic Cancer, Chinese Academy of Medical Sciences(2019RU019), Hangzhou, 310003, China; Key Laboratory of Organ Transplantation, Research Center for Diagnosis and Treatment of Hepatobiliary Diseases, Zhejiang Province, Hangzhou, 310003, China
| | - Xizhi Yu
- Division of Hepatobiliary and Pancreatic Surgery, Department of Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310003, China; NHC Key Laboratory of Combined Multi-organ Transplantation, Hangzhou, 310003, China; Key Laboratory of the Diagnosis and Treatment of Organ Transplantation, Research Unit of Collaborative Diagnosis and Treatment for Hepatobiliary and Pancreatic Cancer, Chinese Academy of Medical Sciences(2019RU019), Hangzhou, 310003, China; Key Laboratory of Organ Transplantation, Research Center for Diagnosis and Treatment of Hepatobiliary Diseases, Zhejiang Province, Hangzhou, 310003, China
| | - Qinchuan Wu
- Division of Hepatobiliary and Pancreatic Surgery, Department of Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310003, China; NHC Key Laboratory of Combined Multi-organ Transplantation, Hangzhou, 310003, China; Key Laboratory of the Diagnosis and Treatment of Organ Transplantation, Research Unit of Collaborative Diagnosis and Treatment for Hepatobiliary and Pancreatic Cancer, Chinese Academy of Medical Sciences(2019RU019), Hangzhou, 310003, China; Key Laboratory of Organ Transplantation, Research Center for Diagnosis and Treatment of Hepatobiliary Diseases, Zhejiang Province, Hangzhou, 310003, China
| | - Jing Mao
- Division of Hepatobiliary and Pancreatic Surgery, Department of Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310003, China; NHC Key Laboratory of Combined Multi-organ Transplantation, Hangzhou, 310003, China; Key Laboratory of the Diagnosis and Treatment of Organ Transplantation, Research Unit of Collaborative Diagnosis and Treatment for Hepatobiliary and Pancreatic Cancer, Chinese Academy of Medical Sciences(2019RU019), Hangzhou, 310003, China; Key Laboratory of Organ Transplantation, Research Center for Diagnosis and Treatment of Hepatobiliary Diseases, Zhejiang Province, Hangzhou, 310003, China
| | - Xi Liu
- Division of Hepatobiliary and Pancreatic Surgery, Department of Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310003, China; NHC Key Laboratory of Combined Multi-organ Transplantation, Hangzhou, 310003, China; Key Laboratory of the Diagnosis and Treatment of Organ Transplantation, Research Unit of Collaborative Diagnosis and Treatment for Hepatobiliary and Pancreatic Cancer, Chinese Academy of Medical Sciences(2019RU019), Hangzhou, 310003, China; Key Laboratory of Organ Transplantation, Research Center for Diagnosis and Treatment of Hepatobiliary Diseases, Zhejiang Province, Hangzhou, 310003, China
| | - Yubo Wang
- Division of Hepatobiliary and Pancreatic Surgery, Department of Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310003, China; NHC Key Laboratory of Combined Multi-organ Transplantation, Hangzhou, 310003, China; Key Laboratory of the Diagnosis and Treatment of Organ Transplantation, Research Unit of Collaborative Diagnosis and Treatment for Hepatobiliary and Pancreatic Cancer, Chinese Academy of Medical Sciences(2019RU019), Hangzhou, 310003, China; Key Laboratory of Organ Transplantation, Research Center for Diagnosis and Treatment of Hepatobiliary Diseases, Zhejiang Province, Hangzhou, 310003, China
| | - Danjing Guo
- NHC Key Laboratory of Combined Multi-organ Transplantation, Hangzhou, 310003, China; Key Laboratory of the Diagnosis and Treatment of Organ Transplantation, Research Unit of Collaborative Diagnosis and Treatment for Hepatobiliary and Pancreatic Cancer, Chinese Academy of Medical Sciences(2019RU019), Hangzhou, 310003, China; Key Laboratory of Organ Transplantation, Research Center for Diagnosis and Treatment of Hepatobiliary Diseases, Zhejiang Province, Hangzhou, 310003, China
| | - Rong Su
- NHC Key Laboratory of Combined Multi-organ Transplantation, Hangzhou, 310003, China; Key Laboratory of the Diagnosis and Treatment of Organ Transplantation, Research Unit of Collaborative Diagnosis and Treatment for Hepatobiliary and Pancreatic Cancer, Chinese Academy of Medical Sciences(2019RU019), Hangzhou, 310003, China; Key Laboratory of Organ Transplantation, Research Center for Diagnosis and Treatment of Hepatobiliary Diseases, Zhejiang Province, Hangzhou, 310003, China
| | - Haiyang Xie
- NHC Key Laboratory of Combined Multi-organ Transplantation, Hangzhou, 310003, China; Key Laboratory of the Diagnosis and Treatment of Organ Transplantation, Research Unit of Collaborative Diagnosis and Treatment for Hepatobiliary and Pancreatic Cancer, Chinese Academy of Medical Sciences(2019RU019), Hangzhou, 310003, China; Key Laboratory of Organ Transplantation, Research Center for Diagnosis and Treatment of Hepatobiliary Diseases, Zhejiang Province, Hangzhou, 310003, China
| | - Shengyong Yin
- NHC Key Laboratory of Combined Multi-organ Transplantation, Hangzhou, 310003, China; Key Laboratory of the Diagnosis and Treatment of Organ Transplantation, Research Unit of Collaborative Diagnosis and Treatment for Hepatobiliary and Pancreatic Cancer, Chinese Academy of Medical Sciences(2019RU019), Hangzhou, 310003, China; Key Laboratory of Organ Transplantation, Research Center for Diagnosis and Treatment of Hepatobiliary Diseases, Zhejiang Province, Hangzhou, 310003, China
| | - Lin Zhou
- NHC Key Laboratory of Combined Multi-organ Transplantation, Hangzhou, 310003, China; Key Laboratory of the Diagnosis and Treatment of Organ Transplantation, Research Unit of Collaborative Diagnosis and Treatment for Hepatobiliary and Pancreatic Cancer, Chinese Academy of Medical Sciences(2019RU019), Hangzhou, 310003, China; Key Laboratory of Organ Transplantation, Research Center for Diagnosis and Treatment of Hepatobiliary Diseases, Zhejiang Province, Hangzhou, 310003, China.
| | - ShuSen Zheng
- Division of Hepatobiliary and Pancreatic Surgery, Department of Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310003, China; NHC Key Laboratory of Combined Multi-organ Transplantation, Hangzhou, 310003, China; Key Laboratory of the Diagnosis and Treatment of Organ Transplantation, Research Unit of Collaborative Diagnosis and Treatment for Hepatobiliary and Pancreatic Cancer, Chinese Academy of Medical Sciences(2019RU019), Hangzhou, 310003, China; Key Laboratory of Organ Transplantation, Research Center for Diagnosis and Treatment of Hepatobiliary Diseases, Zhejiang Province, Hangzhou, 310003, China.
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10
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Fukuyama K, Motomura E, Okada M. Age-Dependent Activation of Pannexin1 Function Contributes to the Development of Epileptogenesis in Autosomal Dominant Sleep-related Hypermotor Epilepsy Model Rats. Int J Mol Sci 2024; 25:1619. [PMID: 38338895 PMCID: PMC10855882 DOI: 10.3390/ijms25031619] [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: 01/12/2024] [Revised: 01/23/2024] [Accepted: 01/25/2024] [Indexed: 02/12/2024] Open
Abstract
To explore the processes of epileptogenesis/ictogenesis, this study determined the age-dependent development of the functional abnormalities in astroglial transmission associated with pannexin1-hemichannel using a genetic rat model of autosomal dominant sleep-related hypermotor epilepsy (ADSHE) named 'S286L-TG'. Pannexin1 expression in the plasma membrane of primary cultured cortical astrocytes and the orbitofrontal cortex (OFC), which is an ADSHE focus region, were determined using capillary immunoblotting. Astroglial D-serine releases induced by artificial high-frequency oscillation (HFO)-evoked stimulation, the removal of extracellular Ca2+, and the P2X7 receptor agonist (BzATP) were determined using ultra-high performance liquid chromatography (UHPLC). The expressions of pannexin1 in the plasma membrane fraction of the OFC in S286L-TG at four weeks old were almost equivalent when compared to the wild type. The pannexin1 expression in the OFC of the wild type non-statistically decreased age-dependently, whereas that in S286L-TG significantly increased age-dependently, resulting in relatively increasing pannexin1 expression from the 7- (at the onset of interictal discharge) and 10-week-old (after the ADSHE seizure onset) S286L-TG compared to the wild type. However, no functional abnormalities of astroglial pannexin1 expression or D-serine release through the pannexin1-hemichannels from the cultured astrocytes of S286L-TG could be detected. Acutely HFO-evoked stimulation, such as physiological ripple burst (200 Hz) and epileptogenic fast ripple burst (500 Hz), frequency-dependently increased both pannexin1 expression in the astroglial plasma membrane and astroglial D-serine release. Neither the selective inhibitors of pannexin1-hemichannel (10PANX) nor connexin43-hemichannel (Gap19) affected astroglial D-serine release during the resting stage, whereas HFO-evoked D-serine release was suppressed by both inhibitors. The inhibitory effect of 10PANX on the ripple burst-evoked D-serine release was more predominant than that of Gap19, whereas fast ripple burst-evoked D-serine release was predominantly suppressed by Gap19 rather than 10PANX. Astroglial D-serine release induced by acute exposure to BzATP was suppressed by 10PANX but not by Gap19. These results suggest that physiological ripple burst during the sleep spindle plays important roles in the organization of some components of cognition in healthy individuals, but conversely, it contributes to the initial development of epileptogenesis/ictogenesis in individuals who have ADSHE vulnerability via activation of the astroglial excitatory transmission associated with pannexin1-hemichannels.
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Affiliation(s)
| | | | - Motohiro Okada
- Department of Neuropsychiatry, Division of Neuroscience, Graduate School of Medicine, Mie University, Tsu 514-8507, Japan; (K.F.); (E.M.)
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11
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Falco MV, Fabbiani G, Maciel C, Valdivia S, Vitureira N, Russo RE. P2X7 receptor activation awakes a dormant stem cell niche in the adult spinal cord. Front Cell Neurosci 2023; 17:1288676. [PMID: 38164435 PMCID: PMC10757934 DOI: 10.3389/fncel.2023.1288676] [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: 09/04/2023] [Accepted: 11/08/2023] [Indexed: 01/03/2024] Open
Abstract
The ependyma of the spinal cord is a latent stem cell niche that is reactivated by injury, generating new cells that migrate to the lesion site to limit the damage. The mechanisms by which ependymal cells are reactivated after injury remain poorly understood. ATP has been proposed to act as a diffusible "danger signal" to alert about damage and start repair. Indeed, spinal cord injury (SCI) generates an increase in extracellular ATP around the lesion epicenter that lasts for several hours and affects the functional outcome after the damage. The P2X7 receptor (P2X7r) has functional properties (e.g., low sensitivity for ATP, high permeability for Ca2+) that makes it a suitable candidate to act as a detector of tissue damage. Because ependymal cells express functional P2X7r that generate an inward current and regenerative Ca2+ waves, we hypothesize that the P2X7r has a main role in the mechanisms by which progenitor-like cells in the ependyma react to tissue damage. To test this possibility, we simulated the P2X7r activation that occurs after SCI by in vivo intraspinal injection of the selective agonist BzATP nearby the central canal. We found that BzATP rescued ependymal cells from quiescence by triggering a proliferative response similar to that generated by injury. In addition, P2X7r activation by BzATP induced a shift of ependymal cells to a glial fibrillary acidic protein (GFAP) phenotype similar to that induced by injury. However, P2X7r activation did not trigger the migration of ependyma-derived cells as occurs after tissue damage. Injection of BzATP induced the expression of connexin 26 (Cx26) in ependymal cells, an event needed for the proliferative reaction after injury. BzATP did not induce these changes in ependymal cells of P2X7-/- mice supporting a specific action on P2X7r. In vivo blockade of P2X7r with the potent antagonist AZ10606120 reduced significantly the injury-induced proliferation of ependymal cells. Our data indicate that P2X7r has a key role in the "awakening" of the ependymal stem cell niche after injury and suggest purinergic signaling is an interesting target to improve the contribution of endogenous progenitors to repair.
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Affiliation(s)
- María Victoria Falco
- Departamento de Neurofisiología Celular y Molecular, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo, Uruguay
| | - Gabriela Fabbiani
- Departamento de Neurofisiología Celular y Molecular, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo, Uruguay
| | - Cecilia Maciel
- Departamento de Neurofisiología Celular y Molecular, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo, Uruguay
| | - Spring Valdivia
- Departamento de Neurofisiología Celular y Molecular, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo, Uruguay
| | - Nathalia Vitureira
- Departamento de Fisiología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Raúl E. Russo
- Departamento de Neurofisiología Celular y Molecular, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo, Uruguay
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12
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Scherr BF, Reiner MF, Baumann F, Höhne K, Müller T, Ayata K, Müller-Quernheim J, Idzko M, Zissel G. Prevention of M2 polarization and temporal limitation of differentiation in monocytes by extracellular ATP. BMC Immunol 2023; 24:11. [PMID: 37353774 PMCID: PMC10288684 DOI: 10.1186/s12865-023-00546-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 06/06/2023] [Indexed: 06/25/2023] Open
Abstract
BACKGROUND Elevated levels of extracellular adenosine triphosphate (ATP) modulate immunologic pathways and are considered to be a danger signal in inflammation, lung fibrosis and cancer. Macrophages can be classified into two main types: M1 macrophages are classically activated, pro-inflammatory macrophages, whereas M2 macrophages are alternatively activated, pro-fibrotic macrophages. In this study, we examined the effect of ATP on differentiation of native human monocytes into these macrophage subtypes. We characterized M1 and M2 like macrophages by their release of Interleukin-1beta (IL-1β) and Chemokine (C-C motif) ligand 18 (CCL18), respectively. RESULTS Monocytes were stimulated with ATP or the P2X7 receptor agonist Benzoylbenzoyl-ATP (Bz-ATP), and the production of various cytokines was analyzed, with a particular focus on CCL18 and IL-1β, along with the expression of different purinergic receptors. Over a 72 h period of cell culture, monocytes spontaneously differentiated to M2 like macrophages, as indicated by an increased release of CCL18. Immediate stimulation of monocytes with ATP resulted in a dose-dependent reduction in CCL18 release, but had no effect on the concentration of IL-1β. In contrast, delayed stimulation with ATP had no effect on either CCL18 or IL-1β release. Similar results were observed in a model of inflammation using lipopolysaccharide-stimulated human monocytes. Stimulation with the P2X7 receptor agonist Bz-ATP mimicked the effect of ATP on M2-macrophage differentiation, indicating that P2X7 is involved in ATP-induced inhibition of CCL18 release. Indeed, P2X7 was downregulated during spontaneous M2 differentiation, which may partially explain the ineffectiveness of late ATP stimulation of monocytes. However, pre-incubation of monocytes with PPADS, Suramin (unselective P2X- and P2Y-receptor blockers) and KN62 (P2X7-antagonist) failed to reverse the reduction of CCL18 by ATP. CONCLUSIONS ATP prevents spontaneous differentiation of monocytes into M2-like macrophages in a dose- and time-dependent manner. These effects were not mediated by P2X and P2Y receptors.
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Affiliation(s)
- Benedikt F Scherr
- Department of Pneumology, Medical Center, Faculty of Medicine, University of Freiburg, Engesserstr. 4 5thFloor, 79106 79108, Freiburg, Germany
- Institute of Intensive Care Medicine, University Hospital Zurich, 8091, Zurich, Switzerland
| | - Martin F Reiner
- Department of Cardiology, University Heart Center, University Hospital Zurich, 8091, Zurich, Switzerland
| | - Flavia Baumann
- Emergency Department, University Hospital Zurich, 8091, Zurich, Switzerland
| | - Kerstin Höhne
- Department of Pneumology, Medical Center, Faculty of Medicine, University of Freiburg, Engesserstr. 4 5thFloor, 79106 79108, Freiburg, Germany
| | - Tobias Müller
- Department of Pneumology, Medical Center, Faculty of Medicine, University of Freiburg, Engesserstr. 4 5thFloor, 79106 79108, Freiburg, Germany
- Department of Pneumology, University Medical Center Mannheim, University of Heidelberg, 68167, Mannheim, Germany
| | - Korcan Ayata
- Department of Pneumology, Medical Center, Faculty of Medicine, University of Freiburg, Engesserstr. 4 5thFloor, 79106 79108, Freiburg, Germany
- Department of Biomedicine, University of Basel, 4031, Basel, Switzerland
| | - Joachim Müller-Quernheim
- Department of Pneumology, Medical Center, Faculty of Medicine, University of Freiburg, Engesserstr. 4 5thFloor, 79106 79108, Freiburg, Germany
| | - Marco Idzko
- Department of Pneumology, Medical Center, Faculty of Medicine, University of Freiburg, Engesserstr. 4 5thFloor, 79106 79108, Freiburg, Germany
- Division of Pulmonology, Department of Medicine II, Medical University of Vienna, 1090, Vienna, Austria
| | - Gernot Zissel
- Department of Pneumology, Medical Center, Faculty of Medicine, University of Freiburg, Engesserstr. 4 5thFloor, 79106 79108, Freiburg, Germany.
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Rupert M, Bhattacharya A, Sivcev S, Knezu M, Cimicka J, Zemkova H. Identification of residues in the first transmembrane domain of the P2X7 that regulates receptor trafficking, sensitization, and dye uptake function. J Neurochem 2023; 165:874-891. [PMID: 36945903 DOI: 10.1111/jnc.15813] [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: 10/16/2022] [Revised: 02/24/2023] [Accepted: 03/14/2023] [Indexed: 03/23/2023]
Abstract
P2X receptors (P2X1-7) are trimeric ion channels activated by extracellular ATP. Each P2X subunit contains two transmembrane helices (TM1 and TM2). We substituted all residues in TM1 of rat P2X7 with alanine or leucine one by one, expressed mutants in HEK293T cells, and examined the pore permeability by recording both membrane currents and fluorescent dye uptake in response to agonist application. Alanine substitution of G27, K30, H34, Y40, F43, L45, M46, and D48 inhibited agonist-stimulated membrane current and dye uptake, and all but one substitution, D48A, prevented surface expression. Mutation V41A partially reduced both membrane current and dye uptake, while W31A and A44L showed reduced dye uptake not accompanied by reduced membrane current. Mutations T28A, I29A, and L33A showed small changes in agonist sensitivity, but they had no or small impact on dye uptake function. Replacing charged residues with residues of the same charge (K30R, H34K, and D48E) rescued receptor function, while replacement with residues of opposite charge inhibited (K30E and H34E) or potentiated (D48K) receptor function. Prolonged stimulation with agonist-induced current facilitation and a leftward shift in the dose-response curve in the P2X7 wild-type and most functional mutants, but sensitization was absent in the W31A, L33A, and A44L. Detailed analysis of the decay of responses revealed two kinetically distinct mechanisms of P2X7 deactivation: fast represents agonist unbinding, and slow might represent resetting of the receptor to the resting closed state. These results indicate that conserved and receptor-specific TM1 residues control surface expression of the P2X7 protein, non-polar residues control receptor sensitization, and D48 regulates intrinsic channel properties.
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Affiliation(s)
- Marian Rupert
- Institute of Physiology, Academy of Sciences of the Czech Republic, Prague, Czech Republic
- 1st Faculty of Medicine, Charles University in Prague, Prague, Czech Republic
| | - Anirban Bhattacharya
- Institute of Physiology, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Sonja Sivcev
- Institute of Physiology, Academy of Sciences of the Czech Republic, Prague, Czech Republic
- Faculty of Sciences, Charles University in Prague, Prague, Czech Republic
| | - Michal Knezu
- Institute of Physiology, Academy of Sciences of the Czech Republic, Prague, Czech Republic
- Faculty of Sciences, Charles University in Prague, Prague, Czech Republic
| | - Jana Cimicka
- Institute of Physiology, Academy of Sciences of the Czech Republic, Prague, Czech Republic
- 1st Faculty of Medicine, Charles University in Prague, Prague, Czech Republic
| | - Hana Zemkova
- Institute of Physiology, Academy of Sciences of the Czech Republic, Prague, Czech Republic
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14
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Grohs L, Cheng L, Cönen S, Haddad BG, Bülow A, Toklucu I, Ernst L, Körner J, Schmalzing G, Lampert A, Machtens JP, Hausmann R. Diclofenac and other non-steroidal anti-inflammatory drugs (NSAIDs) are competitive antagonists of the human P2X3 receptor. Front Pharmacol 2023; 14:1120360. [PMID: 37007008 PMCID: PMC10060569 DOI: 10.3389/fphar.2023.1120360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Accepted: 02/24/2023] [Indexed: 03/18/2023] Open
Abstract
Introduction: The P2X3 receptor (P2X3R), an ATP-gated non-selective cation channel of the P2X receptor family, is expressed in sensory neurons and involved in nociception. P2X3R inhibition was shown to reduce chronic and neuropathic pain. In a previous screening of 2000 approved drugs, natural products, and bioactive substances, various non-steroidal anti-inflammatory drugs (NSAIDs) were found to inhibit P2X3R-mediated currents.Methods: To investigate whether the inhibition of P2X receptors contributes to the analgesic effect of NSAIDs, we characterized the potency and selectivity of various NSAIDs at P2X3R and other P2XR subtypes using two-electrode voltage clamp electrophysiology.Results: We identified diclofenac as a hP2X3R and hP2X2/3R antagonist with micromolar potency (with IC50 values of 138.2 and 76.7 µM, respectively). A weaker inhibition of hP2X1R, hP2X4R, and hP2X7R by diclofenac was determined. Flufenamic acid (FFA) inhibited hP2X3R, rP2X3R, and hP2X7R (IC50 values of 221 µM, 264.1 µM, and ∼900 µM, respectively), calling into question its use as a non-selective ion channel blocker, when P2XR-mediated currents are under study. Inhibition of hP2X3R or hP2X2/3R by diclofenac could be overcome by prolonged ATP application or increasing concentrations of the agonist α,β-meATP, respectively, indicating competition of diclofenac and the agonists. Molecular dynamics simulation showed that diclofenac largely overlaps with ATP bound to the open state of the hP2X3R. Our results suggest a competitive antagonism through which diclofenac, by interacting with residues of the ATP-binding site, left flipper, and dorsal fin domains, inhibits the gating of P2X3R by conformational fixation of the left flipper and dorsal fin domains. In summary, we demonstrate the inhibition of the human P2X3 receptor by various NSAIDs. Diclofenac proved to be the most effective antagonist with a strong inhibition of hP2X3R and hP2X2/3R and a weaker inhibition of hP2X1R, hP2X4R, and hP2X7R.Discussion: Considering their involvement in nociception, inhibition of hP2X3R and hP2X2/3R by micromolar concentrations of diclofenac, which are rarely reached in the therapeutic range, may play a minor role in analgesia compared to the high-potency cyclooxygenase inhibition but may explain the known side effect of taste disturbances caused by diclofenac.
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Affiliation(s)
- Laura Grohs
- Institute of Clinical Pharmacology, RWTH Aachen University, Aachen, Germany
- Department of Neurology, University Hospital, RWTH Aachen University, Aachen, Germany
| | - Linhan Cheng
- Institute of Clinical Pharmacology, RWTH Aachen University, Aachen, Germany
| | - Saskia Cönen
- Institute of Clinical Pharmacology, RWTH Aachen University, Aachen, Germany
- Molecular and Cellular Physiology (IBI-1), Institute of Biological Information Processing (IBI), Forschungszentrum Jülich, Jülich, Germany
| | - Bassam G. Haddad
- Molecular and Cellular Physiology (IBI-1), Institute of Biological Information Processing (IBI), Forschungszentrum Jülich, Jülich, Germany
| | - Astrid Bülow
- Institute of Clinical Pharmacology, RWTH Aachen University, Aachen, Germany
- Department of Plastic Surgery, Hand Surgery—Burn Center, University Hospital, RWTH Aachen University, Aachen, Germany
| | - Idil Toklucu
- Institute of Physiology (Neurophysiology), RWTH Aachen University, Aachen, Germany
| | - Lisa Ernst
- Institute for Laboratory Animal Science and Experimental Surgery, RWTH Aachen University, Aachen, Germany
| | - Jannis Körner
- Institute of Physiology (Neurophysiology), RWTH Aachen University, Aachen, Germany
- Department of Anesthesiology, University Hospital, RWTH Aachen University, Aachen, Germany
| | - Günther Schmalzing
- Institute of Clinical Pharmacology, RWTH Aachen University, Aachen, Germany
| | - Angelika Lampert
- Institute of Physiology (Neurophysiology), RWTH Aachen University, Aachen, Germany
| | - Jan-Philipp Machtens
- Institute of Clinical Pharmacology, RWTH Aachen University, Aachen, Germany
- Molecular and Cellular Physiology (IBI-1), Institute of Biological Information Processing (IBI), Forschungszentrum Jülich, Jülich, Germany
| | - Ralf Hausmann
- Institute of Clinical Pharmacology, RWTH Aachen University, Aachen, Germany
- *Correspondence: Ralf Hausmann,
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15
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Triazoles with inhibitory action on P2X7R impaired the acute inflammatory response in vivo and modulated the hemostatic balance in vitro and ex vivo. Inflamm Res 2022; 72:237-250. [PMID: 36463339 PMCID: PMC9734322 DOI: 10.1007/s00011-022-01664-1] [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: 07/04/2022] [Revised: 10/20/2022] [Accepted: 10/25/2022] [Indexed: 12/05/2022] Open
Abstract
OBJECTIVE The present study aimed to investigate five triazole compounds as P2X7R inhibitors and evaluate their ability to reduce acute inflammation in vivo. MATERIAL The synthetic compounds were labeled 5e, 8h, 9i, 11, and 12. TREATMENT We administered 500 ng/kg triazole analogs in vivo, (1-10 µM) in vitro, and 1000 mg/kg for toxicological assays. METHODS For this, we used in vitro experiments, such as platelet aggregation, in vivo experiments of paw edema and peritonitis in mice, and in silico experiments. RESULTS The tested substances 5e, 8h, 9i, 11, and 12 produced a significant reduction in paw edema. Molecules 5e, 8h, 9i, 11, and 12 inhibited carrageenan-induced peritonitis. Substances 5e, 8h, 9i, 11, and 12 showed an anticoagulant effect, and 5e at a concentration of 10 µM acted as a procoagulant. All derivatives, except for 11, had pharmacokinetic, physicochemical, and toxicological properties suitable for substances that are candidates for new drugs. In addition, the ADMET risk assessment shows that derivatives 8h, 11, 5e, and 9i have high pharmacological potential. Finally, docking tests indicated that the derivatives have binding energies comparable to the reference antagonist with a competitive inhibition profile. CONCLUSIONS Together, the results indicate that the molecules tested as antagonist drugs of P2X7R had anti-inflammatory action against the acute inflammatory response.
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16
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Abstract
Within the family of purinergic receptors, the P2X1 receptor is a ligand-gated ion channel that plays a role in urogenital, immune and cardiovascular function. Specifically, the P2X1 receptor has been implicated in controlling smooth muscle contractions of the vas deferens and therefore has emerged as an exciting drug target for male contraception. In addition, the P2X1 receptor contributes to smooth muscle contractions of the bladder and is a target to treat bladder dysfunction. Finally, platelets and neutrophils have populations of P2X1 receptors that could be targeted for thrombosis and inflammatory conditions. Drugs that specifically target the P2X1 receptor have been challenging to develop, and only recently have small molecule antagonists of the P2X1 receptor been available. However, these ligands need further biological validation for appropriate selectivity and drug-like properties before they will be suitable for use in preclinical models of disease. Although the atomic structure of the P2X1 receptor has yet to be determined, the recent discovery of several other P2X receptor structures and improvements in the field of structural biology suggests that this is now a distinct possibility. Such efforts may significantly improve drug discovery efforts at the P2X1 receptor.
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17
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Isaak A, Dobelmann C, Füsser FT, Erlitz KS, Koch O, Junker A. Unveiling the Structure-Activity Relationships at the Orthosteric Binding Site of P2X Ion Channels: The Route to Selectivity. J Med Chem 2022; 65:11291-11308. [PMID: 35930402 DOI: 10.1021/acs.jmedchem.2c00812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The orthosteric ATP-binding site of the P2X receptors is poorly understood. Only a few compounds were well characterized for their P2X receptor functional activity and subtype selectivity. This study represents the first fully functional characterization of various ATP derivatives combined with in silico studies to advance the understanding of SARs at the orthosteric binding sites of P2X receptors leading to the identification of 2-chloro-3-trifluoromethylbenzoyl ATP ester as a novel pan-P2X receptor agonist and several subtype-selective P2X receptor agonists. Furthermore, esterification of both hydroxyl functions of ATP using 1-naphthoic acid has led to compound 26 acting as an antagonist at P2X1-4 and P2X2/3 receptors and an agonist at P2X7 receptors. This particular ATP derivative will allow interrogating the P2X7 receptor function while antagonizing all other P2X receptor subtypes and therefore serve as a valuable pharmacological tool in the future.
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Affiliation(s)
- Andreas Isaak
- European Institute for Molecular Imaging (EIMI), Waldeyerstr. 15, Münster 48149, Germany
| | - Clemens Dobelmann
- European Institute for Molecular Imaging (EIMI), Waldeyerstr. 15, Münster 48149, Germany
| | - Friederike Theresa Füsser
- Institut für Pharmazeutische und Medizinische Chemie der Universität Münster, Corrensstr. 48, Münster 48149, Germany
| | | | - Oliver Koch
- Institut für Pharmazeutische und Medizinische Chemie der Universität Münster, Corrensstr. 48, Münster 48149, Germany
| | - Anna Junker
- European Institute for Molecular Imaging (EIMI), Waldeyerstr. 15, Münster 48149, Germany
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18
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Chen Z, Huang Q, Song X, Ford NC, Zhang C, Xu Q, Lay M, He SQ, Dong X, Hanani M, Guan Y. Purinergic signaling between neurons and satellite glial cells of mouse dorsal root ganglia modulates neuronal excitability in vivo. Pain 2022; 163:1636-1647. [PMID: 35027518 PMCID: PMC9771604 DOI: 10.1097/j.pain.0000000000002556] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 11/24/2021] [Indexed: 10/19/2022]
Abstract
ABSTRACT Primary sensory neurons in dorsal root ganglia (DRG) are wrapped by satellite glial cells (SGCs), and neuron-SGC interaction may affect somatosensation, especially nociceptive transmission. P2-purinergic receptors (P2Rs) are key elements in the two-way interactions between DRG neurons and SGCs. However, because the cell types are in such close proximity, conventional approaches such as in vitro culture and electrophysiologic recordings are not adequate to investigate the physiologically relevant responses of these cells at a population level. Here, we performed in vivo calcium imaging to survey the activation of hundreds of DRG neurons in Pirt-GCaMP6s mice and to assess SGC activation in GFAP-GCaMP6s mice in situ. By combining pharmacologic and electrophysiologic techniques, we investigated how ganglionic purinergic signaling initiated by α,β-methyleneadenosine 5'-triphosphate (α,β-MeATP) modulates neuronal activity and excitability at a population level. We found that α,β-MeATP induced robust activation of small neurons-likely nociceptors-through activation of P2X3R. Large neurons, which are likely non-nociceptive, were also activated by α,β-MeATP, but with a delay. Blocking pannexin 1 channels attenuated the late phase response of DRG neurons, indicating that P2R stimulation may subsequently induce paracrine ATP release, which could further activate cells in the ganglion. Moreover, ganglionic α,β-MeATP treatment in vivo sensitized small neurons and enhanced responses of spinal wide-dynamic-range neurons to subsequent C-fiber inputs, suggesting that modulation via ganglionic P2R signaling could significantly affect nociceptive neuron excitability and pain transmission. Therefore, targeting functional P2Rs within ganglia may represent an important new strategy for pain modulation.
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Affiliation(s)
- Zhiyong Chen
- Department of Anesthesiology and Critical Care Medicine, the Johns Hopkins University, School of Medicine, Baltimore, MD, United States
| | - Qian Huang
- Department of Anesthesiology and Critical Care Medicine, the Johns Hopkins University, School of Medicine, Baltimore, MD, United States
| | - Xiaodan Song
- Department of Anesthesiology and Critical Care Medicine, the Johns Hopkins University, School of Medicine, Baltimore, MD, United States
| | - Neil C. Ford
- Department of Anesthesiology and Critical Care Medicine, the Johns Hopkins University, School of Medicine, Baltimore, MD, United States
| | - Chi Zhang
- Department of Anesthesiology and Critical Care Medicine, the Johns Hopkins University, School of Medicine, Baltimore, MD, United States
| | - Qian Xu
- The Solomon H. Snyder Department of Neuroscience, Center for Sensory Biology, Johns Hopkins University, School of Medicine, Baltimore, MD, United States
- Howard Hughes Medical Institute, Johns Hopkins University, School of Medicine, Baltimore, MD, United States
| | - Mark Lay
- The Solomon H. Snyder Department of Neuroscience, Center for Sensory Biology, Johns Hopkins University, School of Medicine, Baltimore, MD, United States
| | - Shao-Qiu He
- Department of Anesthesiology and Critical Care Medicine, the Johns Hopkins University, School of Medicine, Baltimore, MD, United States
| | - Xinzhong Dong
- The Solomon H. Snyder Department of Neuroscience, Center for Sensory Biology, Johns Hopkins University, School of Medicine, Baltimore, MD, United States
- Howard Hughes Medical Institute, Johns Hopkins University, School of Medicine, Baltimore, MD, United States
| | - Menachem Hanani
- Laboratory of Experimental Surgery, Hadassah-Hebrew University Medical Center, Faculty of Medicine, Hebrew University of Jerusalem, Mount Scopus, Jerusalem, Israel
| | - Yun Guan
- Department of Anesthesiology and Critical Care Medicine, the Johns Hopkins University, School of Medicine, Baltimore, MD, United States
- Department of Neurological Surgery, Johns Hopkins University, School of Medicine, Baltimore, MD, United States
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19
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BzATP Activates Satellite Glial Cells and Increases the Excitability of Dorsal Root Ganglia Neurons In Vivo. Cells 2022; 11:cells11152280. [PMID: 35892578 PMCID: PMC9330736 DOI: 10.3390/cells11152280] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Revised: 07/18/2022] [Accepted: 07/21/2022] [Indexed: 12/14/2022] Open
Abstract
The purinergic system plays an important role in pain transmission. Recent studies have suggested that activation of P2-purinergic receptors (P2Rs) may be involved in neuron-satellite glial cell (SGC) interactions in the dorsal root ganglia (DRG), but the details remain unclear. In DRG, P2X7R is selectively expressed in SGCs, which closely surround neurons, and is highly sensitive to 3’-O-(4-Benzoyl) benzoyl-ATP (BzATP). Using calcium imaging in intact mice to survey a large number of DRG neurons and SGCs, we examined how intra-ganglionic purinergic signaling initiated by BzATP affects neuronal activities in vivo. We developed GFAP-GCaMP6s and Pirt-GCaMP6s mice to express the genetically encoded calcium indicator GGCaM6s in SGCs and DRG neurons, respectively. The application of BzATP to the ganglion induced concentration-dependent activation of SGCs in GFAP-GCaMP6s mice. In Pirt-GCaMP6s mice, BzATP initially activated more large-size neurons than small-size ones. Both glial and neuronal responses to BzATP were blocked by A438079, a P2X7R-selective antagonist. Moreover, blockers to pannexin1 channels (probenecid) and P2X3R (A317491) also reduced the actions of BzATP, suggesting that P2X7R stimulation may induce the opening of pannexin1 channels, leading to paracrine ATP release, which could further excite neurons by acting on P2X3Rs. Importantly, BzATP increased the responses of small-size DRG neurons and wide-dynamic range spinal neurons to subsequent peripheral stimuli. Our findings suggest that intra-ganglionic purinergic signaling initiated by P2X7R activation could trigger SGC-neuron interaction in vivo and increase DRG neuron excitability.
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20
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Sophocleous RA, Ooi L, Sluyter R. The P2X4 Receptor: Cellular and Molecular Characteristics of a Promising Neuroinflammatory Target. Int J Mol Sci 2022; 23:ijms23105739. [PMID: 35628550 PMCID: PMC9147237 DOI: 10.3390/ijms23105739] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 05/18/2022] [Accepted: 05/18/2022] [Indexed: 02/07/2023] Open
Abstract
The adenosine 5′-triphosphate-gated P2X4 receptor channel is a promising target in neuroinflammatory disorders, but the ability to effectively target these receptors in models of neuroinflammation has presented a constant challenge. As such, the exact role of P2X4 receptors and their cell signalling mechanisms in human physiology and pathophysiology still requires further elucidation. To this end, research into the molecular mechanisms of P2X4 receptor activation, modulation, and inhibition has continued to gain momentum in an attempt to further describe the role of P2X4 receptors in neuroinflammation and other disease settings. Here we provide an overview of the current understanding of the P2X4 receptor, including its expression and function in cells involved in neuroinflammatory signalling. We discuss the pharmacology of P2X4 receptors and provide an overview of P2X4-targeting molecules, including agonists, positive allosteric modulators, and antagonists. Finally, we discuss the use of P2X4 receptor modulators and antagonists in models of neuroinflammatory cell signalling and disease.
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Affiliation(s)
- Reece Andrew Sophocleous
- Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia; (R.A.S.); (L.O.)
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia
| | - Lezanne Ooi
- Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia; (R.A.S.); (L.O.)
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia
| | - Ronald Sluyter
- Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia; (R.A.S.); (L.O.)
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia
- Correspondence: ; Tel.: +612-4221-5508
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21
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Landini L, Souza Monteiro de Araujo D, Titiz M, Geppetti P, Nassini R, De Logu F. TRPA1 Role in Inflammatory Disorders: What Is Known So Far? Int J Mol Sci 2022; 23:ijms23094529. [PMID: 35562920 PMCID: PMC9101260 DOI: 10.3390/ijms23094529] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 04/11/2022] [Accepted: 04/18/2022] [Indexed: 02/01/2023] Open
Abstract
The transient receptor potential ankyrin 1 (TRPA1), a member of the TRP superfamily of channels, is primarily localized in a subpopulation of primary sensory neurons of the trigeminal, vagal, and dorsal root ganglia, where its activation mediates neurogenic inflammatory responses. TRPA1 expression in resident tissue cells, inflammatory, and immune cells, through the indirect modulation of a large series of intracellular pathways, orchestrates a range of cellular processes, such as cytokine production, cell differentiation, and cytotoxicity. Therefore, the TRPA1 pathway has been proposed as a protective mechanism to detect and respond to harmful agents in various pathological conditions, including several inflammatory diseases. Specific attention has been paid to TRPA1 contribution to the transition of inflammation and immune responses from an early defensive response to a chronic pathological condition. In this view, TRPA1 antagonists may be regarded as beneficial tools for the treatment of inflammatory conditions.
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22
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Second Messenger 2'3'-cyclic GMP-AMP (2'3'-cGAMP):Synthesis, transmission, and degradation. Biochem Pharmacol 2022; 198:114934. [PMID: 35104477 DOI: 10.1016/j.bcp.2022.114934] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Revised: 01/20/2022] [Accepted: 01/24/2022] [Indexed: 01/07/2023]
Abstract
Cyclic GMP-AMP synthase (cGAS) senses foreign DNA to produce 2'3'-cyclic GMP-AMP (2'3'-cGAMP). 2'3'-cGAMP is a second messenger that binds and activates the adaptor protein STING, which triggers the innate immune response. As a STING agonist, the small molecule 2'3'-cGAMP plays pivotal roles in antiviral defense and has adjuvant applications, and anti-tumor effects. 2'3'-cGAMP and its analogs are thus putative targets for immunotherapy and are currently being testedin clinical trials to treat solid tumors. However, several barriers to further development have emerged from these studies, such as evidence of immune and inflammatory side-effects, poor pharmacokinetics, and undesirable biodistribution. Here, we review the status of 2'3'-cGAMP research and outline the role of 2'3'-cGAMP in immune signaling, adjuvant applications, and cancer immunotherapy, as well as various 2'3'-cGAMP detection methods.
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23
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Wong J, Gu BJ, Teoh H, Krupa M, Monif M, Slee M, Wiley JS. Flow Cytometry Identifies an Early Stage of Platelet Apoptosis Produced by Agonists of the P2X1 and P2X7 Receptors. Platelets 2022; 33:621-631. [PMID: 35042433 DOI: 10.1080/09537104.2021.1981844] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Platelets express P2X1 receptors and our data also show the expression of P2X7 receptors. We studied the role of both receptors in platelet apoptosis by incubation of PRP with P2X agonists, then centrifuged to remove viable platelets, and analyzed the supernatant by flow cytometry to identify a sparse platelet-derived population that stained with MitoTracker dyes and CD41. BzATP, a potent agonist of P2X receptors, and ABT737, an activator of intrinsic apoptosis, produced altered platelets that stained moderately for annexin V and corresponded to an early stage apoptotic platelet (ESAP). Over a range of BzATP concentrations, we observed a dose-dependent formation of ESAPs between 5 and 500 uM BzATP, together with a variable formation of ESAPs at nanomolar ATP or BzATP (50-200 nM). Production of ESAPs occurred with αβ-meATP, while responses with either BzATP or αβ-meATP showed desensitization at a higher agonist concentration. Formation of ESAPs by either 100 nM or 0.5 mM BzATP was inhibited by preincubation of platelets with latrunculin A, an inhibitor of the actin cytoskeleton that prevents apoptosis. ESAP production was totally inhibited by preincubation of platelets with methyl-beta-cyclodextrin, which removes cholesterol from lipid rafts. Our data show that both P2X1 and P2X7 receptors are localized in platelet lipid rafts where P2X-agonists act to produce early stage apoptotic platelets.
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Affiliation(s)
- Joelyn Wong
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria, Australia
| | - Ben J Gu
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria, Australia
| | - Harry Teoh
- College of Medicine and Public Health, Flinders University of South Australia, Bedford Park, Australia
| | - Malgorzata Krupa
- College of Medicine and Public Health, Flinders University of South Australia, Bedford Park, Australia
| | - Mastura Monif
- Department of Neurology, Royal Melbourne Hospital, Parkville, Australia.,Department of Neuroscience, Monash University, Clayton, Australia
| | - Mark Slee
- College of Medicine and Public Health, Flinders University of South Australia, Bedford Park, Australia
| | - James S Wiley
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria, Australia.,Haematology Department, Box Hill Hospital, Australia
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24
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Holzer AK, Karreman C, Suciu I, Furmanowsky LS, Wohlfarth H, Loser D, Dirks WG, Pardo González E, Leist M. OUP accepted manuscript. Stem Cells Transl Med 2022; 11:727-741. [PMID: 35689659 PMCID: PMC9299516 DOI: 10.1093/stcltm/szac031] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 04/09/2022] [Indexed: 11/12/2022] Open
Abstract
In vitro models of the peripheral nervous system would benefit from further refinements to better support studies on neuropathies. In particular, the assessment of pain-related signals is still difficult in human cell cultures. Here, we harnessed induced pluripotent stem cells (iPSCs) to generate peripheral sensory neurons enriched in nociceptors. The objective was to generate a culture system with signaling endpoints suitable for pharmacological and toxicological studies. Neurons generated by conventional differentiation protocols expressed moderate levels of P2X3 purinergic receptors and only low levels of TRPV1 capsaicin receptors, when maturation time was kept to the upper practically useful limit of 6 weeks. As alternative approach, we generated cells with an inducible NGN1 transgene. Ectopic expression of this transcription factor during a defined time window of differentiation resulted in highly enriched nociceptor cultures, as determined by functional (P2X3 and TRPV1 receptors) and immunocytochemical phenotyping, complemented by extensive transcriptome profiling. Single cell recordings of Ca2+-indicator fluorescence from >9000 cells were used to establish the “fraction of reactive cells” in a stimulated population as experimental endpoint, that appeared robust, transparent and quantifiable. To provide an example of application to biomedical studies, functional consequences of prolonged exposure to the chemotherapeutic drug oxaliplatin were examined at non-cytotoxic concentrations. We found (i) neuronal (allodynia-like) hypersensitivity to otherwise non-activating mechanical stimulation that could be blocked by modulators of voltage-gated sodium channels; (ii) hyper-responsiveness to TRPV1 receptor stimulation. These findings and several other measured functional alterations indicate that the model is suitable for pharmacological and toxicological studies related to peripheral neuropathies.
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Affiliation(s)
- Anna-Katharina Holzer
- In vitro Toxicology and Biomedicine, Department Inaugurated by the Doerenkamp-Zbinden Foundation, University of Konstanz, Konstanz, Germany
- Graduate School Biological Sciences (GBS), University of Konstanz, Konstanz, Germany
| | - Christiaan Karreman
- In vitro Toxicology and Biomedicine, Department Inaugurated by the Doerenkamp-Zbinden Foundation, University of Konstanz, Konstanz, Germany
| | - Ilinca Suciu
- In vitro Toxicology and Biomedicine, Department Inaugurated by the Doerenkamp-Zbinden Foundation, University of Konstanz, Konstanz, Germany
| | - Lara-Seline Furmanowsky
- In vitro Toxicology and Biomedicine, Department Inaugurated by the Doerenkamp-Zbinden Foundation, University of Konstanz, Konstanz, Germany
| | - Harald Wohlfarth
- In vitro Toxicology and Biomedicine, Department Inaugurated by the Doerenkamp-Zbinden Foundation, University of Konstanz, Konstanz, Germany
| | - Dominik Loser
- NMI Natural and Medical Sciences Institute at the University of Tübingen, Reutlingen, Germany
| | - Wilhelm G Dirks
- Department of Human and Animal Cell Lines, DSMZ, German Collection of Microorganisms and Cell Cultures and German Biological Resource Center, Braunschweig, Germany
| | - Emilio Pardo González
- NMI Natural and Medical Sciences Institute at the University of Tübingen, Reutlingen, Germany
| | - Marcel Leist
- Corresponding author: Marcel Leist, PhD, In Vitro Toxicology and Biomedicine, Dept Inaugurated by the Doerenkamp-Zbinden Foundation at the University of Konstanz, Universitaetsstr. 10, Konstanz 78457, Germany.
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25
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Yan D, Earp HS, DeRyckere D, Graham DK. Targeting MERTK and AXL in EGFR Mutant Non-Small Cell Lung Cancer. Cancers (Basel) 2021; 13:5639. [PMID: 34830794 PMCID: PMC8616094 DOI: 10.3390/cancers13225639] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 11/09/2021] [Accepted: 11/10/2021] [Indexed: 12/20/2022] Open
Abstract
MERTK and AXL are members of the TAM family of receptor tyrosine kinases and are abnormally expressed in 69% and 93% of non-small cell lung cancers (NSCLCs), respectively. Expression of MERTK and/or AXL provides a survival advantage for NSCLC cells and correlates with lymph node metastasis, drug resistance, and disease progression in patients with NSCLC. The TAM receptors on host tumor infiltrating cells also play important roles in the immunosuppressive tumor microenvironment. Thus, MERTK and AXL are attractive biologic targets for NSCLC treatment. Here, we will review physiologic and oncologic roles for MERTK and AXL with an emphasis on the potential to target these kinases in NSCLCs with activating EGFR mutations.
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Affiliation(s)
- Dan Yan
- Aflac Cancer and Blood Disorders Center, Children’s Healthcare of Atlanta, Department of Pediatrics, Emory University, Atlanta, GA 30322, USA; (D.Y.); (D.D.)
| | - H. Shelton Earp
- UNC Lineberger Comprehensive Cancer Center, Department of Medicine, Chapel Hill, NC 27599, USA;
- Department of Pharmacology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Deborah DeRyckere
- Aflac Cancer and Blood Disorders Center, Children’s Healthcare of Atlanta, Department of Pediatrics, Emory University, Atlanta, GA 30322, USA; (D.Y.); (D.D.)
| | - Douglas K. Graham
- Aflac Cancer and Blood Disorders Center, Children’s Healthcare of Atlanta, Department of Pediatrics, Emory University, Atlanta, GA 30322, USA; (D.Y.); (D.D.)
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26
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Receptor-specific Ca 2+ oscillation patterns mediated by differential regulation of P2Y purinergic receptors in rat hepatocytes. iScience 2021; 24:103139. [PMID: 34646983 PMCID: PMC8496176 DOI: 10.1016/j.isci.2021.103139] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 07/26/2021] [Accepted: 09/14/2021] [Indexed: 11/21/2022] Open
Abstract
Extracellular agonists linked to inositol-1,4,5-trisphosphate (IP3) formation elicit cytosolic Ca2+ oscillations in many cell types, but despite a common signaling pathway, distinct agonist-specific Ca2+ spike patterns are observed. Using qPCR, we show that rat hepatocytes express multiple purinergic P2Y and P2X receptors (R). ADP acting through P2Y1R elicits narrow Ca2+ oscillations, whereas UTP acting through P2Y2R elicits broad Ca2+ oscillations, with composite patterns observed for ATP. P2XRs do not play a role at physiological agonist levels. The discrete Ca2+ signatures reflect differential effects of protein kinase C (PKC), which selectively modifies the falling phase of the Ca2+ spikes. Negative feedback by PKC limits the duration of P2Y1R-induced Ca2+ spikes in a manner that requires extracellular Ca2+. By contrast, P2Y2R is resistant to PKC negative feedback. Thus, the PKC leg of the bifurcated IP3 signaling pathway shapes unique Ca2+ oscillation patterns that allows for distinct cellular responses to different agonists. Distinct stereotypic Ca2+ oscillations are elicited by P2Y1 and P2Y2 receptors P2X receptors do not contribute to the generation of Ca2+ oscillations Agonist-specific Ca2+ spike shapes reflect discrete modes of PKC negative feedback Bifurcation of IP3/PKC signaling yields unique Ca2+ oscillation signatures
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27
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Ford AP, Dillon MP, Kitt MM, Gever JR. The discovery and development of gefapixant. Auton Neurosci 2021; 235:102859. [PMID: 34403981 DOI: 10.1016/j.autneu.2021.102859] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 07/06/2021] [Accepted: 07/21/2021] [Indexed: 01/02/2023]
Abstract
Gefapixant is the approved generic name for a compound also known as MK-7264, and prior to that AF-219 and RO-4926219. It is the first-in-class clinically developed antagonist for the P2X3 subtype of trimeric ionotropic purinergic receptors, a family of ATP-gated excitatory ion channels, showing nanomolar potency for the human P2X3 homotrimeric channel and essentially no activity at related channels devoid of P2X3 subunits. As the first P2X3 antagonist to have progressed into clinical studies it has now progressed to the point of successful completion of Phase 3 investigations for the treatment of cough, and the NDA application is under review with US FDA for treatment of refractory chronic cough or unexplained chronic cough. The molecule was discovered in the laboratories of Roche Pharmaceuticals in Palo Alto, California, but clinical development then continued with the formation of Afferent Pharmaceuticals for the purpose of identifying the optimal therapeutic indication for this novel mechanism and establishing a clinical plan for development in the optimal patient populations selected. Geoff Burnstock was a close collaborator and advisor to the P2X3 program for close to two decades of discovery and development. Progression of gefapixant through later stage clinical studies has been conducted by the research laboratories of Merck & Co., Inc., Kenilworth, NJ, USA (MRL; following acquisition of Afferent in 2016), who may commercialize the product once authorization has been granted by regulatory authorities.
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Affiliation(s)
- Anthony P Ford
- CuraSen Therapeutics, 930 Brittan Avenue, Suite 306, San Carlos, CA 94070, USA.
| | - Michael P Dillon
- Ideaya Biosciences, 7000 Shoreline Court, Suite 350, South San Francisco, CA 94080, USA
| | - Michael M Kitt
- Axalbion LTD., C/O Medicines Evaluation Unit, The Langley Building, Southmoor Road, Wythenshawe, M23 9QZ Manchester, UK
| | - Joel R Gever
- CuraSen Therapeutics, 930 Brittan Avenue, Suite 306, San Carlos, CA 94070, USA
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28
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Magni L, Bouazzi R, Heredero Olmedilla H, Petersen PSS, Tozzi M, Novak I. The P2X7 Receptor Stimulates IL-6 Release from Pancreatic Stellate Cells and Tocilizumab Prevents Activation of STAT3 in Pancreatic Cancer Cells. Cells 2021; 10:cells10081928. [PMID: 34440697 PMCID: PMC8391419 DOI: 10.3390/cells10081928] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 06/30/2021] [Accepted: 07/23/2021] [Indexed: 12/12/2022] Open
Abstract
Pancreatic stellate cells (PSCs) are important pancreatic fibrogenic cells that interact with pancreatic cancer cells to promote the progression of pancreatic ductal adenocarcinoma (PDAC). In the tumor microenvironment (TME), several factors such as cytokines and nucleotides contribute to this interplay. Our aim was to investigate whether there is an interaction between IL-6 and nucleotide signaling, in particular, that mediated by the ATP-sensing P2X7 receptor (P2X7R). Using human cell lines of PSCs and cancer cells, as well as primary PSCs from mice, we show that ATP is released from both PSCs and cancer cells in response to mechanical and metabolic cues that may occur in the TME, and thus activate the P2X7R. Functional studies using P2X7R agonists and inhibitors show that the receptor is involved in PSC proliferation, collagen secretion and IL-6 secretion and it promotes cancer cell migration in a human PSC-cancer cell co-culture. Moreover, conditioned media from P2X7R-stimulated PSCs activated the JAK/STAT3 signaling pathway in cancer cells. The monoclonal antibody inhibiting the IL-6 receptor, Tocilizumab, inhibited this signaling. In conclusion, we show an important mechanism between PSC-cancer cell interaction involving ATP and IL-6, activating P2X7 and IL-6 receptors, respectively, both potential therapeutic targets in PDAC.
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MESH Headings
- Animals
- Antibodies, Monoclonal, Humanized/pharmacology
- Antibodies, Monoclonal, Humanized/therapeutic use
- Antineoplastic Agents, Immunological/pharmacology
- Antineoplastic Agents, Immunological/therapeutic use
- Carcinoma, Pancreatic Ductal/drug therapy
- Carcinoma, Pancreatic Ductal/metabolism
- Carcinoma, Pancreatic Ductal/physiopathology
- Cell Communication
- Cell Line, Tumor
- Cell Movement
- Cell Proliferation
- Humans
- Interleukin-6/metabolism
- Male
- Mice
- Pancreatic Stellate Cells/metabolism
- Pancreatic Stellate Cells/physiology
- Receptors, Purinergic P2X7/metabolism
- STAT3 Transcription Factor/metabolism
- Signal Transduction
- Tumor Microenvironment
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29
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Loser D, Hinojosa MG, Blum J, Schaefer J, Brüll M, Johansson Y, Suciu I, Grillberger K, Danker T, Möller C, Gardner I, Ecker GF, Bennekou SH, Forsby A, Kraushaar U, Leist M. Functional alterations by a subgroup of neonicotinoid pesticides in human dopaminergic neurons. Arch Toxicol 2021; 95:2081-2107. [PMID: 33778899 PMCID: PMC8166715 DOI: 10.1007/s00204-021-03031-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 03/17/2021] [Indexed: 12/16/2022]
Abstract
Neonicotinoid pesticides, originally developed to target the insect nervous system, have been reported to interact with human receptors and to activate rodent neurons. Therefore, we evaluated in how far these compounds may trigger signaling in human neurons, and thus, affect the human adult or developing nervous system. We used SH-SY5Y neuroblastoma cells as established model of nicotinic acetylcholine receptor (nAChR) signaling. In parallel, we profiled dopaminergic neurons, generated from LUHMES neuronal precursor cells, as novel system to study nAChR activation in human post-mitotic neurons. Changes of the free intracellular Ca2+ concentration ([Ca2+]i) were used as readout, and key findings were confirmed by patch clamp recordings. Nicotine triggered typical neuronal signaling responses that were blocked by antagonists, such as tubocurarine and mecamylamine. Pharmacological approaches suggested a functional expression of α7 and non-α7 nAChRs on LUHMES cells. In this novel test system, the neonicotinoids acetamiprid, imidacloprid, clothianidin and thiacloprid, but not thiamethoxam and dinotefuran, triggered [Ca2+]i signaling at 10-100 µM. Strong synergy of the active neonicotinoids (at low micromolar concentrations) with the α7 nAChR-positive allosteric modulator PNU-120596 was observed in LUHMES and SH-SY5Y cells, and specific antagonists fully inhibited such signaling. To provide a third line of evidence for neonicotinoid signaling via nAChR, we studied cross-desensitization: pretreatment of LUHMES and SH-SY5Y cells with active neonicotinoids (at 1-10 µM) blunted the signaling response of nicotine. The pesticides (at 3-30 µM) also blunted the response to the non-α7 agonist ABT 594 in LUHMES cells. These data show that human neuronal cells are functionally affected by low micromolar concentrations of several neonicotinoids. An effect of such signals on nervous system development is a toxicological concern.
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Affiliation(s)
- Dominik Loser
- NMI Natural and Medical Sciences Institute at the University of Tübingen, 72770, Reutlingen, Germany
- NMI TT GmbH, 72770, Reutlingen, Germany
- In Vitro Toxicology and Biomedicine, Department Inaugurated by the Doerenkamp-Zbinden Foundation, University of Konstanz, Universitaetsstr. 10, 78457, Konstanz, Germany
| | - Maria G Hinojosa
- Department of Biochemistry and Biophysics, Stockholm University, 106 91, Stockholm, Sweden
| | - Jonathan Blum
- In Vitro Toxicology and Biomedicine, Department Inaugurated by the Doerenkamp-Zbinden Foundation, University of Konstanz, Universitaetsstr. 10, 78457, Konstanz, Germany
| | - Jasmin Schaefer
- NMI Natural and Medical Sciences Institute at the University of Tübingen, 72770, Reutlingen, Germany
- NMI TT GmbH, 72770, Reutlingen, Germany
| | - Markus Brüll
- In Vitro Toxicology and Biomedicine, Department Inaugurated by the Doerenkamp-Zbinden Foundation, University of Konstanz, Universitaetsstr. 10, 78457, Konstanz, Germany
| | - Ylva Johansson
- Department of Biochemistry and Biophysics, Stockholm University, 106 91, Stockholm, Sweden
| | - Ilinca Suciu
- In Vitro Toxicology and Biomedicine, Department Inaugurated by the Doerenkamp-Zbinden Foundation, University of Konstanz, Universitaetsstr. 10, 78457, Konstanz, Germany
| | - Karin Grillberger
- Department of Pharmaceutical Sciences, University of Vienna, Vienna, Austria
| | - Timm Danker
- NMI Natural and Medical Sciences Institute at the University of Tübingen, 72770, Reutlingen, Germany
- NMI TT GmbH, 72770, Reutlingen, Germany
| | - Clemens Möller
- Life Sciences Faculty, Albstadt-Sigmaringen University, 72488, Sigmaringen, Germany
| | - Iain Gardner
- CERTARA UK Limited, Simcyp Division, Level 2-Acero, 1 Concourse Way, Sheffield, S1 2BJ, UK
| | - Gerhard F Ecker
- Department of Pharmaceutical Sciences, University of Vienna, Vienna, Austria
| | | | - Anna Forsby
- Department of Biochemistry and Biophysics, Stockholm University, 106 91, Stockholm, Sweden
| | - Udo Kraushaar
- NMI Natural and Medical Sciences Institute at the University of Tübingen, 72770, Reutlingen, Germany
| | - Marcel Leist
- In Vitro Toxicology and Biomedicine, Department Inaugurated by the Doerenkamp-Zbinden Foundation, University of Konstanz, Universitaetsstr. 10, 78457, Konstanz, Germany.
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Functional P2X 7 Receptors in the Auditory Nerve of Hearing Rodents Localize Exclusively to Peripheral Glia. J Neurosci 2021; 41:2615-2629. [PMID: 33563723 DOI: 10.1523/jneurosci.2240-20.2021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 12/03/2020] [Accepted: 01/09/2021] [Indexed: 11/21/2022] Open
Abstract
P2X7 receptors (P2X7Rs) are associated with numerous pathophysiological mechanisms, and this promotes them as therapeutic targets for certain neurodegenerative conditions. However, the identity of P2X7R-expressing cells in the nervous system remains contentious. Here, we examined P2X7R functionality in auditory nerve cells from rodents of either sex, and determined their functional and anatomic expression pattern. In whole-cell recordings from rat spiral ganglion cultures, the purinergic agonist 2',3'-O-(4-benzoylbenzoyl)-ATP (BzATP) activated desensitizing currents in spiral ganglion neurons (SGNs) but non-desensitizing currents in glia that were blocked by P2X7R-specific antagonists. In imaging experiments, BzATP gated sustained Ca2+ entry into glial cells. BzATP-gated uptake of the fluorescent dye YO-PRO-1 was reduced and slowed by P2X7R-specific antagonists. In rats, P2X7Rs were immuno-localized predominantly within satellite glial cells (SGCs) and Schwann cells (SCs). P2X7R expression was not detected in the portion of the auditory nerve within the central nervous system. Mouse models allowed further exploration of the distribution of cochlear P2X7Rs. In GENSAT reporter mice, EGFP expression driven via the P2rx7 promoter was evident in SGCs and SCs but was undetectable in SGNs. A second transgenic model showed a comparable cellular distribution of EGFP-tagged P2X7Rs. In wild-type mice the discrete glial expression was confirmed using a P2X7-specific nanobody construct. Our study shows that P2X7Rs are expressed by peripheral glial cells, rather than by afferent neurons. Description of functional signatures and cellular distributions of these enigmatic proteins in the peripheral nervous system (PNS) will help our understanding of ATP-dependent effects contributing to hearing loss and other sensory neuropathies.SIGNIFICANCE STATEMENT P2X7 receptors (P2X7Rs) have been the subject of much scrutiny in recent years. They have been promoted as therapeutic targets in a number of diseases of the nervous system, yet the specific cellular location of these receptors remains the subject of intense debate. In the auditory nerve, connecting the inner ear to the brainstem, we show these multimodal ATP-gated channels localize exclusively to peripheral glial cells rather than the sensory neurons, and are not evident in central glia. Physiologic responses in the peripheral glia display classical hallmarks of P2X7R activation, including the formation of ion-permeable and also macromolecule-permeable pores. These qualities suggest these proteins could contribute to glial-mediated inflammatory processes in the auditory periphery under pathologic disease states.
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Jarvis MF. Geoffery Burnstock's influence on the evolution of P2X3 receptor pharmacology. Purinergic Signal 2021; 17:33-39. [PMID: 33029713 PMCID: PMC7955014 DOI: 10.1007/s11302-020-09744-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 09/30/2020] [Indexed: 12/29/2022] Open
Affiliation(s)
- Michael F Jarvis
- Global Medical Affairs, Abbvie, Inc., 1 N Waukegan Rd., North Chicago, IL, 60064, USA.
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Teixeira JM, Pimentel RM, Abdalla HB, Sousa HMX, Macedo CG, Napimoga MH, Tambeli CH, Oliveira‐Fusaro MCG, Clemente‐Napimoga JT. P2X7‐induced nociception in the temporomandibular joint of rats depends on inflammatory mechanisms and C‐fibres sensitization. Eur J Pain 2021; 25:1107-1118. [DOI: 10.1002/ejp.1732] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Juliana M. Teixeira
- Faculdade São Leopoldo Mandic Área de Fisiologia Instituto de Pesquisas São Leopoldo Mandic Campinas Brazil
| | - Rafael M. Pimentel
- Faculdade São Leopoldo Mandic Área de Fisiologia Instituto de Pesquisas São Leopoldo Mandic Campinas Brazil
| | - Henrique B. Abdalla
- Faculdade São Leopoldo Mandic Área de Fisiologia Instituto de Pesquisas São Leopoldo Mandic Campinas Brazil
| | - Hortência M. X. Sousa
- Laboratory of Orofacial Pain Department of Physiology Piracicaba Dental School State University of Campinas (UNICAMP) Piracicaba Brazil
| | - Cristina G. Macedo
- Faculdade São Leopoldo Mandic Área de Fisiologia Instituto de Pesquisas São Leopoldo Mandic Campinas Brazil
| | - Marcelo H. Napimoga
- Faculdade São Leopoldo Mandic Área de Imunologia Instituto de Pesquisas São Leopoldo Mandic Campinas Brazil
| | - Cláudia H. Tambeli
- Department of Structural and Functional Biology Institute of Biology State University of Campinas (UNICAMP) Campinas Brazil
| | - Maria C. G. Oliveira‐Fusaro
- Laboratory of Studies of Pain and Inflammation School of Applied Sciences State University of Campinas (UNICAMP) Limeira São Paulo Brazil
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That was then, this is now: the development of our knowledge and understanding of P2 receptor subtypes. Purinergic Signal 2021; 17:9-23. [PMID: 33527235 PMCID: PMC7954963 DOI: 10.1007/s11302-021-09763-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Accepted: 01/06/2021] [Indexed: 11/17/2022] Open
Abstract
P2 receptors are present in virtually all tissues and cell types in the human body, and they mediate the physiological and pharmacological actions of extracellular purine and pyrimidine nucleotides. They were first characterised and named by Geoff Burnstock in 1978, then subdivided into P2X and P2Y purinoceptors in 1985 on the basis of pharmacological criteria in functional studies on native receptors. Molecular cloning of receptors in the 1990s revealed P2X receptors to comprise seven different subunits that interact to produce functional homo- and heterotrimeric ligand-gated cation channels. A family of eight P2Y G protein–coupled receptors were also cloned, which can form homo- and heterodimers. Deep insight into the molecular mechanisms of agonist and antagonist action has been provided by more recent determination of the tertiary and quaternary structures of several P2X and P2Y receptor subtypes. Agonists and antagonists that are highly selective for individual subtypes are now available and some are in clinical use. This has all come about because of the intelligence, insight and drive of the force of nature that was Geoff Burnstock.
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Loser D, Schaefer J, Danker T, Möller C, Brüll M, Suciu I, Ückert AK, Klima S, Leist M, Kraushaar U. Human neuronal signaling and communication assays to assess functional neurotoxicity. Arch Toxicol 2021; 95:229-252. [PMID: 33269408 PMCID: PMC7811517 DOI: 10.1007/s00204-020-02956-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 11/16/2020] [Indexed: 01/08/2023]
Abstract
Prediction of drug toxicity on the human nervous system still relies mainly on animal experiments. Here, we developed an alternative system allowing assessment of complex signaling in both individual human neurons and on the network level. The LUHMES cultures used for our approach can be cultured in 384-well plates with high reproducibility. We established here high-throughput quantification of free intracellular Ca2+ concentrations [Ca2+]i as broadly applicable surrogate of neuronal activity and verified the main processes by patch clamp recordings. Initially, we characterized the expression pattern of many neuronal signaling components and selected the purinergic receptors to demonstrate the applicability of the [Ca2+]i signals for quantitative characterization of agonist and antagonist responses on classical ionotropic neurotransmitter receptors. This included receptor sub-typing and the characterization of the anti-parasitic drug suramin as modulator of the cellular response to ATP. To exemplify potential studies on ion channels, we characterized voltage-gated sodium channels and their inhibition by tetrodotoxin, saxitoxin and lidocaine, as well as their opening by the plant alkaloid veratridine and the food-relevant marine biotoxin ciguatoxin. Even broader applicability of [Ca2+]i quantification as an end point was demonstrated by measurements of dopamine transporter activity based on the membrane potential-changing activity of this neurotransmitter carrier. The substrates dopamine or amphetamine triggered [Ca2+]i oscillations that were synchronized over the entire culture dish. We identified compounds that modified these oscillations by interfering with various ion channels. Thus, this new test system allows multiple types of neuronal signaling, within and between cells, to be assessed, quantified and characterized for their potential disturbance.
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Affiliation(s)
- Dominik Loser
- NMI Natural and Medical Sciences Institute at the University of Tuebingen, 72770, Reutlingen, Germany
- NMI TT GmbH, 72770, Reutlingen, Germany
- Life Sciences Faculty, Albstadt-Sigmaringen University, 72488, Sigmaringen, Germany
| | - Jasmin Schaefer
- NMI Natural and Medical Sciences Institute at the University of Tuebingen, 72770, Reutlingen, Germany
- NMI TT GmbH, 72770, Reutlingen, Germany
| | | | - Clemens Möller
- Life Sciences Faculty, Albstadt-Sigmaringen University, 72488, Sigmaringen, Germany
| | - Markus Brüll
- In Vitro Toxicology and Biomedicine, Department Inaugurated by the Doerenkamp-Zbinden Foundation, University of Konstanz, Universitaetsstr. 10, 78457, Constance, Germany
| | - Ilinca Suciu
- In Vitro Toxicology and Biomedicine, Department Inaugurated by the Doerenkamp-Zbinden Foundation, University of Konstanz, Universitaetsstr. 10, 78457, Constance, Germany
| | - Anna-Katharina Ückert
- In Vitro Toxicology and Biomedicine, Department Inaugurated by the Doerenkamp-Zbinden Foundation, University of Konstanz, Universitaetsstr. 10, 78457, Constance, Germany
| | - Stefanie Klima
- In Vitro Toxicology and Biomedicine, Department Inaugurated by the Doerenkamp-Zbinden Foundation, University of Konstanz, Universitaetsstr. 10, 78457, Constance, Germany
| | - Marcel Leist
- In Vitro Toxicology and Biomedicine, Department Inaugurated by the Doerenkamp-Zbinden Foundation, University of Konstanz, Universitaetsstr. 10, 78457, Constance, Germany.
| | - Udo Kraushaar
- NMI Natural and Medical Sciences Institute at the University of Tuebingen, 72770, Reutlingen, Germany
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Dissection of P2X4 and P2X7 Receptor Current Components in BV-2 Microglia. Int J Mol Sci 2020; 21:ijms21228489. [PMID: 33187309 PMCID: PMC7696836 DOI: 10.3390/ijms21228489] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 11/09/2020] [Accepted: 11/09/2020] [Indexed: 12/21/2022] Open
Abstract
Microglia cells represent the immune system of the central nervous system. They become activated by ATP released from damaged and inflamed tissue via purinergic receptors. Ionotropic purinergic P2X4 and P2X7 receptors have been shown to be involved in neurological inflammation and pain sensation. Whether the two receptors assemble exclusively as homotrimers or also as heterotrimers is still a matter of debate. We investigated the expression of P2X receptors in BV-2 microglia cells applying the whole-cell voltage-clamp technique. We dissected P2X4 and P2X7 receptor-mediated current components by using specific P2X4 and P2X7 receptor blockers and by their characteristic current kinetics. We found that P2X4 and P2X7 receptors are activated independently from each other, indicating that P2X4/P2X7 heteromers are not of functional significance in these cells. The pro-inflammatory mediators lipopolysaccharide and interferon γ, if applied in combination, upregulated P2X4, but not P2X7 receptor-dependent current components also arguing against phenotypically relevant heteromerization of P2X4 and P2X7 receptor subunits.
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36
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Development of a Mouse Reporter Strain for the Purinergic P2X 2 Receptor. eNeuro 2020; 7:ENEURO.0203-20.2020. [PMID: 32669344 PMCID: PMC7418537 DOI: 10.1523/eneuro.0203-20.2020] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 06/23/2020] [Accepted: 07/03/2020] [Indexed: 02/06/2023] Open
Abstract
The ATP-sensitive P2X2 ionotropic receptor plays a critical role in a number of signal processes including taste and hearing, carotid body detection of hypoxia, the exercise pressor reflex and sensory transduction of mechanical stimuli in the airways and bladder. Elucidation of the role of P2X2 has been hindered by the lack of selective tools. In particular, detection of P2X2 using established pharmacological and biochemical techniques yields dramatically different expression patterns, particularly in the peripheral and central nervous systems. Here, we have developed a knock-in P2X2-cre mouse, which we crossed with a cre-sensitive tdTomato reporter mouse to determine P2X2 expression. P2X2 was found in more than 80% of nodose vagal afferent neurons, but not in jugular vagal afferent neurons. Reporter expression correlated in vagal neurons with sensitivity to α,β methylene ATP (αβmATP). P2X2 was expressed in 75% of petrosal afferents, but only 12% and 4% of dorsal root ganglia (DRG) and trigeminal afferents, respectively. P2X2 expression was limited to very few cell types systemically. Together with the central terminals of P2X2-expressing afferents, reporter expression in the CNS was mainly found in brainstem neurons projecting mossy fibers to the cerebellum, with little expression in the hippocampus or cortex. The structure of peripheral terminals of P2X2-expressing afferents was demonstrated in the tongue (taste buds), carotid body, trachea and esophagus. P2X2 was observed in hair cells and support cells in the cochlear, but not in spiral afferent neurons. This mouse strain provides a novel approach to the identification and manipulation of P2X2-expressing cell types.
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Carluccio M, Zuccarini M, Ziberi S, Giuliani P, Morabito C, Mariggiò MA, Lonardo MT, Adinolfi E, Orioli E, Di Iorio P, Caciagli F, Ciccarelli R. Involvement of P2X7 Receptors in the Osteogenic Differentiation of Mesenchymal Stromal/Stem Cells Derived from Human Subcutaneous Adipose Tissue. Stem Cell Rev Rep 2020; 15:574-589. [PMID: 30955192 DOI: 10.1007/s12015-019-09883-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The ionotropic P2X7 receptor (P2X7R) is involved in bone homeostasis but its role in osteogenesis is controversial. Thus, we investigated the expression of P2X7R and the effects exerted by its modulation in mesenchymal stromal cells from human subcutaneous adipose tissue (S-ASCs), which have potential therapeutic application in bone regenerative medicine. We found that undifferentiated S-ASCs expressed P2X7R and its functional splice variants P2X7AR and P2X7BR. Cell stimulation by P2X7R agonist BzATP (100 μM) neither modified proliferation nor caused membrane pore opening while increasing intracellular Ca2+ levels and migration. The P2X7R antagonist A438079 reversed these effects. However, 25-100 μM BzATP, administered to S-ASCs undergoing osteogenic differentiation, dose-dependently decreased extracellular matrix mineralization and expression of osteogenic transcription factors Runx2, alkaline phosphatase and osteopontin. These effects were not coupled to cell proliferation reduction or to cell death increase, but were associated to decrease in P2X7AR and P2X7BR expression. In contrast, expression of P2X7R, especially P2X7BR isoform, significantly increased during the osteogenic process. Noteworthy, the antagonist A438079, administered alone, at first restrained cell differentiation, enhancing it later. Accordingly, A438079 reversed BzATP effects only in the second phase of S-ASCs osteogenic differentiation. Apyrase, a diphosphohydrolase converting ATP/ADP into AMP, showed a similar behavior. Altogether, findings related to A438079 or apyrase effects suggest an earlier and prevailing pro-osteogenic activity by endogenous ATP and a later one by adenosine derived from endogenous ATP metabolism. Conversely, P2X7R pharmacological stimulation by BzATP, mimicking the effects of high ATP levels occurring during tissue injuries, depressed receptor expression/activity impairing MSC osteogenic differentiation.
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Affiliation(s)
- Marzia Carluccio
- Department of Medical, Oral and Biotechnology Sciences, Section of Pharmacology, University of Chieti-Pescara, Via dei Vestini 29, 66100, Chieti, Italy.,Aging Research Center and Translational Medicine, University of Chieti-Pescara, Chieti, Italy.,StemTeCh Group, Chieti, Italy
| | - Mariachiara Zuccarini
- Department of Medical, Oral and Biotechnology Sciences, Section of Pharmacology, University of Chieti-Pescara, Via dei Vestini 29, 66100, Chieti, Italy.,Aging Research Center and Translational Medicine, University of Chieti-Pescara, Chieti, Italy
| | - Sihana Ziberi
- Department of Medical, Oral and Biotechnology Sciences, Section of Pharmacology, University of Chieti-Pescara, Via dei Vestini 29, 66100, Chieti, Italy.,Aging Research Center and Translational Medicine, University of Chieti-Pescara, Chieti, Italy.,StemTeCh Group, Chieti, Italy
| | - Patricia Giuliani
- Department of Medical, Oral and Biotechnology Sciences, Section of Pharmacology, University of Chieti-Pescara, Via dei Vestini 29, 66100, Chieti, Italy.,Aging Research Center and Translational Medicine, University of Chieti-Pescara, Chieti, Italy
| | - Caterina Morabito
- Aging Research Center and Translational Medicine, University of Chieti-Pescara, Chieti, Italy.,StemTeCh Group, Chieti, Italy.,Department of Neuroscience, Imaging and Clinical Sciences, University of Chieti-Pescara, Chieti, Italy
| | - Maria A Mariggiò
- Aging Research Center and Translational Medicine, University of Chieti-Pescara, Chieti, Italy.,StemTeCh Group, Chieti, Italy.,Department of Neuroscience, Imaging and Clinical Sciences, University of Chieti-Pescara, Chieti, Italy
| | | | - Elena Adinolfi
- Department of Morphology, Surgery end Experimental Medicine, University of Ferrara, Ferrara, Italy
| | - Elisa Orioli
- Department of Morphology, Surgery end Experimental Medicine, University of Ferrara, Ferrara, Italy
| | - Patrizia Di Iorio
- Department of Medical, Oral and Biotechnology Sciences, Section of Pharmacology, University of Chieti-Pescara, Via dei Vestini 29, 66100, Chieti, Italy.,Aging Research Center and Translational Medicine, University of Chieti-Pescara, Chieti, Italy
| | - Francesco Caciagli
- Department of Medical, Oral and Biotechnology Sciences, Section of Pharmacology, University of Chieti-Pescara, Via dei Vestini 29, 66100, Chieti, Italy.,Aging Research Center and Translational Medicine, University of Chieti-Pescara, Chieti, Italy
| | - Renata Ciccarelli
- Department of Medical, Oral and Biotechnology Sciences, Section of Pharmacology, University of Chieti-Pescara, Via dei Vestini 29, 66100, Chieti, Italy. .,Aging Research Center and Translational Medicine, University of Chieti-Pescara, Chieti, Italy. .,StemTeCh Group, Chieti, Italy.
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38
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Resolving the Ionotropic P2X4 Receptor Mystery Points Towards a New Therapeutic Target for Cardiovascular Diseases. Int J Mol Sci 2020; 21:ijms21145005. [PMID: 32679900 PMCID: PMC7404342 DOI: 10.3390/ijms21145005] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 07/09/2020] [Accepted: 07/13/2020] [Indexed: 12/18/2022] Open
Abstract
Adenosine triphosphate (ATP) is a primordial versatile autacoid that changes its role from an intracellular energy saver to a signaling molecule once released to the extracellular milieu. Extracellular ATP and its adenosine metabolite are the main activators of the P2 and P1 purinoceptor families, respectively. Mounting evidence suggests that the ionotropic P2X4 receptor (P2X4R) plays pivotal roles in the regulation of the cardiovascular system, yet further therapeutic advances have been hampered by the lack of selective P2X4R agonists. In this review, we provide the state of the art of the P2X4R activity in the cardiovascular system. We also discuss the role of P2X4R activation in kidney and lungs vis a vis their interplay to control cardiovascular functions and dysfunctions, including putative adverse effects emerging from P2X4R activation. Gathering this information may prompt further development of selective P2X4R agonists and its translation to the clinical practice.
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Sophocleous RA, Berg T, Finol-Urdaneta RK, Sluyter V, Keshiya S, Bell L, Curtis SJ, Curtis BL, Seavers A, Bartlett R, Dowton M, Stokes L, Ooi L, Sluyter R. Pharmacological and genetic characterisation of the canine P2X4 receptor. Br J Pharmacol 2020; 177:2812-2829. [PMID: 32017039 DOI: 10.1111/bph.15009] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Revised: 01/16/2020] [Accepted: 01/17/2020] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND AND PURPOSE P2X4 receptors are emerging therapeutic targets for treating chronic pain and cardiovascular disease. Dogs are well-recognised natural models of human disease, but information regarding P2X4 receptors in dogs is lacking. To aid the development and validation of P2X4 receptor ligands, we have characterised and compared canine and human P2X4 receptors. EXPERIMENTAL APPROACH Genomic DNA was extracted from whole blood samples from 101 randomly selected dogs and sequenced across the P2RX4 gene to identify potential missense variants. Recombinant canine and human P2X4 receptors tagged with Emerald GFP were expressed in 1321N1 and HEK293 cells and analysed by immunoblotting and confocal microscopy. In these cells, receptor pharmacology was characterised using nucleotide-induced Fura-2 AM measurements of intracellular Ca2+ and known P2X4 receptor antagonists. P2X4 receptor-mediated inward currents in HEK293 cells were assessed by automated patch clamp. KEY RESULTS No P2RX4 missense variants were identified in any canine samples. Canine and human P2X4 receptors were localised primarily to lysosomal compartments. ATP was the primary agonist of canine P2X4 receptors with near identical efficacy and potency at human receptors. 2'(3')-O-(4-benzoylbenzoyl)-ATP, but not ADP, was a partial agonist with reduced potency for canine P2X4 receptors compared to the human orthologues. Five antagonists inhibited canine P2X4 receptors, with 1-(2,6-dibromo-4-isopropyl-phenyl)-3-(3-pyridyl)urea displaying reduced sensitivity and potency at canine P2X4 receptors. CONCLUSION AND IMPLICATIONS P2X4 receptors are highly conserved across dog pedigrees and display expression patterns and pharmacological profiles similar to human receptors, supporting validation and use of therapeutic agents for P2X4 receptor-related disease onset and management in dogs and humans.
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Affiliation(s)
- Reece A Sophocleous
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia.,Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
| | - Tracey Berg
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia.,Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
| | - Rocio K Finol-Urdaneta
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia.,Electrophysiology Facility for Cell Phenotyping and Drug Discovery, Wollongong, NSW, Australia
| | - Vanessa Sluyter
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia.,Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
| | - Shikara Keshiya
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia.,Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
| | - Lachlan Bell
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia.,Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
| | | | | | - Aine Seavers
- Oak Flats Veterinary Clinic, Oak Flats, NSW, Australia
| | - Rachael Bartlett
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia.,Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
| | - Mark Dowton
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
| | - Leanne Stokes
- School of Pharmacy, University of East Anglia, Norwich, UK
| | - Lezanne Ooi
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia.,Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
| | - Ronald Sluyter
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia.,Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
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40
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P2X3 and P2X2/3 receptors activation induces articular hyperalgesia by an indirect sensitization of the primary afferent nociceptor in the rats' knee joint. Eur J Pharmacol 2020; 879:173054. [PMID: 32145326 DOI: 10.1016/j.ejphar.2020.173054] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 02/27/2020] [Accepted: 02/28/2020] [Indexed: 12/30/2022]
Abstract
We have previously shown that endogenous adenosine 5'-triphosphate (ATP), via P2X3 and P2X2/3 receptors, plays an essential role in carrageenan-induced articular hyperalgesia model in rats' knee joint. In the present study, we used the rat knee joint incapacitation test, Enzyme-Linked Immunosorbent Assay (ELISA), and myeloperoxidase enzyme activity assay, to test the hypothesis that the activation of P2X3 and P2X2/3 receptors by their agonist induces articular hyperalgesia mediated by the inflammatory mediators bradykinin, prostaglandin, sympathomimetic amines, pro-inflammatory cytokines and by neutrophil migration. We also tested the hypothesis that the activation of P2X3 and P2X2/3 receptors contributes to the articular hyperalgesia induced by the inflammatory mediators belonging to carrageenan inflammatory cascade. The non-selective P2X3 and P2X2/3 receptors agonist αβ-meATP induced a dose-dependent articular hyperalgesia, which was significantly reduced by the selective antagonists for P2X3 and P2X2/3 receptors (A-317491), bradykinin B1- (DALBK) or B2-receptors (bradyzide), β1-(atenolol) or β2-adrenoceptors (ICI-118,551), by the pre-treatment with cyclooxygenase inhibitor (indomethacin) or with the nonspecific selectin inhibitor (Fucoidan). αβ-meATP induced the release of pro-inflammatory cytokines TNFα, IL-1β, IL-6, and CINC-1, as well as the neutrophil migration. Moreover, the co-administration of A-317491 significantly reduced the articular hyperalgesia induced by bradykinin, prostaglandin E2 (PGE2), and dopamine. These findings suggest that peripheral P2X3 and P2X2/3 receptors activation induces articular hyperalgesia by an indirect sensitization of the primary afferent nociceptor of rats' knee joint through the release of inflammatory mediators. Further, they also indicate that the activation of these purinergic receptors by endogenous ATP mediates the bradykinin-, PGE2-, and dopamine-induced articular hyperalgesia.
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41
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Blockade of the Phagocytic Receptor MerTK on Tumor-Associated Macrophages Enhances P2X7R-Dependent STING Activation by Tumor-Derived cGAMP. Immunity 2020; 52:357-373.e9. [PMID: 32049051 DOI: 10.1016/j.immuni.2020.01.014] [Citation(s) in RCA: 230] [Impact Index Per Article: 57.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 12/03/2019] [Accepted: 01/22/2020] [Indexed: 12/19/2022]
Abstract
Clearance of apoptotic cells by macrophages prevents excessive inflammation and supports immune tolerance. Here, we examined the effect of blocking apoptotic cell clearance on anti-tumor immune response. We generated an antibody that selectively inhibited efferocytosis by phagocytic receptor MerTK. Blockade of MerTK resulted in accumulation of apoptotic cells within tumors and triggered a type I interferon response. Treatment of tumor-bearing mice with anti-MerTK antibody stimulated T cell activation and synergized with anti-PD-1 or anti-PD-L1 therapy. The anti-tumor effect induced by anti-MerTK treatment was lost in Stinggt/gt mice, but not in Cgas-/- mice. Abolishing cGAMP production in Cgas-/- tumor cells, depletion of extracellular ATP, or inactivation of the ATP-gated P2X7R channel also compromised the effects of MerTK blockade. Mechanistically, extracellular ATP acted via P2X7R to enhance the transport of extracellular cGAMP into macrophages and subsequent STING activation. Thus, MerTK blockade increases tumor immunogenicity and potentiates anti-tumor immunity, which has implications for cancer immunotherapy.
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Upregulation of Epithelial-To-Mesenchymal Transition Markers and P2X7 Receptors Is Associated to Increased Invasiveness Caused by P2X7 Receptor Stimulation in Human Glioblastoma Stem Cells. Cells 2019; 9:cells9010085. [PMID: 31905754 PMCID: PMC7016938 DOI: 10.3390/cells9010085] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 12/23/2019] [Accepted: 12/25/2019] [Indexed: 12/11/2022] Open
Abstract
Glioblastoma (GBM) stem cells (GSCs), which contribute to GBM unfavorable prognosis, show high expression levels of ATP/P2X7 receptors (P2X7R). Here, we reported that cells exposure to 2’(3’)-O-(4-benzoylbenzoyl)-ATP (BzATP), a P2X7R agonist, up-regulated the expression of markers associated to epithelial-to-mesenchymal transition (EMT), a process likely contributing to GSC malignancy, and increased GSC migration/invasiveness like the known EMT inducer, Transforming Growth Factor β1 (TGFβ1). These effects were coupled to phosphorylation of SMAD2, a downstream effector in the TGFβ pathway, suggesting its involvement in P2X7R-mediated activity in GSCs. All BzATP effects, including a decrease in the caspase 3/7 activity in GSC medium, were mostly counteracted by the P2X7R antagonist A438079. Finally, BzATP increased the subunit expression of two main human P2X7R splice variants, the full-length P2X7A and the truncated P2X7B, lacking the carboxylic tail, which have different functional properties depending on their arrangement. Since up-regulation of A/B subunits might favor their assembly into a heterotrimeric P2X7R with great sensitivity towards agonists and cell energy support, this is in line with increased EMT markers expression, cell migration/invasion and GSC survival observed following P2X7R stimulation. As in GBM microenvironment extracellular ATP levels may activate P2X7R, our data suggest a P2X7R role in GBM recurrence/invasiveness.
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Beswick P, Wahab B, Honey MA, Paradowski M, Jiang K, Lochner M, Murrell-Lagnado RD, Thompson AJ. A challenge finding P2X1 and P2X4 ligands. Neuropharmacology 2019; 157:107674. [PMID: 31238045 DOI: 10.1016/j.neuropharm.2019.107674] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 05/24/2019] [Accepted: 06/17/2019] [Indexed: 01/09/2023]
Abstract
Identifying novel small-molecule P2X1 and P2X4 ligands with sub-type specificity and high-affinity remains a pharmacological challenge. Here we use computational methods, electrophysiology and fluorescent microplate assays to screen for ligand candidates acting at these receptors. Modelling and docking identified 80 compounds for testing at P2X4 receptors, and 20 of these showed >50% inhibition in fluorescence-based assays, making them appealing for further SAR studies. Confirmation of activity by two-electrode voltage clamp, followed by their elaboration resulted in only minor improvements in potency, with the highest IC50 being 295 μM. Testing on P2X1 receptors, resulted in a series of biguanide compounds that yielded a maximum IC50 of 100 μM, but no consistent SAR could be found. Potencies of established antagonists gave expected results, although the measured potencies varied between techniques and no antagonism could be found for compounds such as paroxetine, carbamazepine, 9(10H)-acridanone, acridinol and phenoxazine-type heterocycles. This study highlights the challenge of identifying P2X4 and P2X1 ligands and suggests that a combination of complimentary approaches is needed if we are to be confident of ligand activities at these receptors.
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Affiliation(s)
- Paul Beswick
- Sussex Drug Discovery Centre, School of Life Sciences, University of Sussex, Brighton, UK
| | - Ben Wahab
- Sussex Drug Discovery Centre, School of Life Sciences, University of Sussex, Brighton, UK
| | - Mark A Honey
- Sussex Drug Discovery Centre, School of Life Sciences, University of Sussex, Brighton, UK
| | | | - Ke Jiang
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bühlstrasse 28, 3012, Bern, Switzerland
| | - Martin Lochner
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bühlstrasse 28, 3012, Bern, Switzerland
| | - Ruth D Murrell-Lagnado
- Sussex Drug Discovery Centre, School of Life Sciences, University of Sussex, Brighton, UK
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Nurkhametova D, Kudryavtsev I, Guselnikova V, Serebryakova M, Giniatullina RR, Wojciechowski S, Tore F, Rizvanov A, Koistinaho J, Malm T, Giniatullin R. Activation of P2X7 Receptors in Peritoneal and Meningeal Mast Cells Detected by Uptake of Organic Dyes: Possible Purinergic Triggers of Neuroinflammation in Meninges. Front Cell Neurosci 2019; 13:45. [PMID: 30814932 PMCID: PMC6381076 DOI: 10.3389/fncel.2019.00045] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Accepted: 01/28/2019] [Indexed: 12/24/2022] Open
Abstract
Extracellular ATP activates inflammasome and triggers the release of multiple cytokines in various immune cells, a process primarily mediated by P2X7 receptors. However, the expression and functional properties of P2X7 receptors in native mast cells in tissues such as meninges where migraine pain originates from have not been explored. Here we report a novel model of murine cultured meningeal mast cells and using these, as well as easily accessible peritoneal mast cells, studied the mechanisms of ATP-mediated mast cell activation. We show that ATP induced a time and dose-dependent activation of peritoneal mast cells as analyzed by the uptake of organic dye YO-PRO1 as well as 4,6-diamidino-2-phenylindole (DAPI). Both YO-PRO1 and DAPI uptake in mast cells was mediated by the P2X7 subtype of ATP receptors as demonstrated by the inhibitory effect of P2X7 antagonist A839977. Consistent with this, significant YO-PRO1 uptake was promoted by the P2X7 agonist 2′,3′-O-(benzoyl-4-benzoyl)-ATP (BzATP). Extracellular ATP-induced degranulation of native and cultured meningeal mast cells was shown with Toluidine Blue staining. Taken together, these data demonstrate the important contribution of P2X7 receptors to ATP-driven activation of mast cells, suggesting these purinergic mechanisms as potential triggers of neuroinflammation and pain sensitization in migraine.
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Affiliation(s)
- Dilyara Nurkhametova
- Laboratory of Neurobiology, Kazan Federal University, Kazan, Russia.,A.I.Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Igor Kudryavtsev
- Department of Immunology, Institute of Experimental Medicine, St. Petersburg, Russia.,Department of Fundamental Medicine, Far Eastern Federal University, Vladivostok, Russia
| | - Valeriia Guselnikova
- A.I.Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland.,Department of General and Special Morphology, Institute of Experimental Medicine, St. Petersburg, Russia
| | - Maria Serebryakova
- Department of Immunology, Institute of Experimental Medicine, St. Petersburg, Russia
| | - Raisa R Giniatullina
- A.I.Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Sara Wojciechowski
- A.I.Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Fatma Tore
- School of Medicine, Biruni University, Istanbul, Turkey
| | - Albert Rizvanov
- Department of Exploratory Research, Scientific and Educational Center of Pharmaceutics, Kazan Federal University, Kazan, Russia
| | - Jari Koistinaho
- A.I.Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland.,Neuroscience Center, Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
| | - Tarja Malm
- A.I.Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Rashid Giniatullin
- Laboratory of Neurobiology, Kazan Federal University, Kazan, Russia.,A.I.Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
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45
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Leeson HC, Chan-Ling T, Lovelace MD, Brownlie JC, Gu BJ, Weible MW. P2X7 receptor signaling during adult hippocampal neurogenesis. Neural Regen Res 2019; 14:1684-1694. [PMID: 31169175 PMCID: PMC6585562 DOI: 10.4103/1673-5374.257510] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Neurogenesis is a persistent and essential feature of the adult mammalian hippocampus. Granular neurons generated from resident pools of stem or progenitor cells provide a mechanism for the formation and consolidation of new memories. Regulation of hippocampal neurogenesis is complex and multifaceted, and numerous signaling pathways converge to modulate cell proliferation, apoptosis, and clearance of cellular debris, as well as synaptic integration of newborn immature neurons. The expression of functional P2X7 receptors in the central nervous system has attracted much interest and the regulatory role of this purinergic receptor during adult neurogenesis has only recently begun to be explored. P2X7 receptors are exceptionally versatile: in their canonical role they act as adenosine triphosphate-gated calcium channels and facilitate calcium-signaling cascades exerting control over the cell via calcium-encoded sensory proteins and transcription factor activation. P2X7 also mediates transmembrane pore formation to regulate cytokine release and facilitate extracellular communication, and when persistently stimulated by high extracellular adenosine triphosphate levels large P2X7 pores form, which induce apoptotic cell death through cytosolic ion dysregulation. Lastly, as a scavenger receptor P2X7 directly facilitates phagocytosis of the cellular debris that arises during neurogenesis, as well as during some disease states. Understanding how P2X7 receptors regulate the physiology of stem and progenitor cells in the adult hippocampus is an important step towards developing useful therapeutic models for regenerative medicine. This review considers the relevant aspects of adult hippocampal neurogenesis and explores how P2X7 receptor activity may influence the molecular physiology of the hippocampus, and neural stem and progenitor cells.
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Affiliation(s)
- Hannah C Leeson
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland; Griffith Institute for Drug Discovery, Griffith University, Brisbane, Queensland, Australia
| | - Tailoi Chan-Ling
- Discipline of Anatomy and Histology, School of Medical Science; Bosch Institute, The University of Sydney, Sydney, New South Wales, Australia
| | - Michael D Lovelace
- Discipline of Anatomy and Histology, School of Medical Science, The University of Sydney; Applied Neurosciences Program, Peter Duncan Neurosciences Research Unit, St. Vincent's Centre for Applied Medical Research; Faculty of Medicine, St. Vincent's Clinical School, University of New South Wales Sydney, Sydney, New South Wales, Australia
| | - Jeremy C Brownlie
- School of Environment and Science, Griffith University, Brisbane, Queensland, Australia
| | - Ben J Gu
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria, Australia
| | - Michael W Weible
- Griffith Institute for Drug Discovery, Griffith University, Brisbane, Queensland; Bosch Institute, The University of Sydney, Sydney, New South Wales; School of Environment and Science, Griffith University, Brisbane, Queensland, Australia
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46
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Keating N, Dev K, Hynes AC, Quinlan LR. Mechanism of luminal ATP activated chloride secretion in a polarized epithelium. J Physiol Sci 2019; 69:85-95. [PMID: 29949063 PMCID: PMC10717936 DOI: 10.1007/s12576-018-0623-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Accepted: 06/06/2018] [Indexed: 10/14/2022]
Abstract
There are both secretory and absorptive pathways working in tandem to support ionic movement driving fluid secretion across epithelia. The mechanisms exerting control of fluid secretion in the oviduct is yet to be fully determined. This study explored the role of apical or luminal extracellular ATP (ATPe)-stimulated ion transport in an oviduct epithelium model, using the Ussing chamber short-circuit current (Isc) technique. Basal Isc in oviduct epithelium in response to apical ATPe comprises both chloride secretion and sodium absorption and has distinct temporal phases. A rapid transient peak followed by a sustained small increase above baseline. Both phases of the apical ATPe Isc response are sensitive to anion (HCO3-, Cl-) and cation (Na+) replacement. Additionally, the role of apical chloride channels, basolateral potassium channels and intracellular calcium in supporting the peak Isc current was confirmed. The role of ATP breakdown to adenosine resulting in the activation of P2 receptors was supported by examining the effects of non-hydrolyzable forms of ATP. A P2YR2 potency profile of ATP = UTP > ADP was generated for the apical membrane, suggesting the involvement of the P2YR2 subtype of purinoceptor. A P2X potency profile of ATP = 2MeSATP > alpha,beta-meATP > BzATP was also generated for the apical membrane. In conclusion, these results provide strong evidence that purinergic activation of apical P2YR2 promotes chloride secretion and is thus an important factor in fluid formation by the oviduct.
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Affiliation(s)
- N Keating
- Physiology, School of Medicine, National University of Ireland, Galway, University Road, Galway, Ireland
| | - K Dev
- Physiology, School of Medicine, National University of Ireland, Galway, University Road, Galway, Ireland
| | - A C Hynes
- Physiology, School of Medicine, National University of Ireland, Galway, University Road, Galway, Ireland
| | - L R Quinlan
- Physiology, School of Medicine, National University of Ireland, Galway, University Road, Galway, Ireland.
- CÚRAM, Centre for Research in Medical Devices, NUI Galway, University Road, Galway, Ireland.
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47
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Thorstenberg ML, Rangel Ferreira MV, Amorim N, Canetti C, Morrone FB, Alves Filho JC, Coutinho-Silva R. Purinergic Cooperation Between P2Y 2 and P2X7 Receptors Promote Cutaneous Leishmaniasis Control: Involvement of Pannexin-1 and Leukotrienes. Front Immunol 2018; 9:1531. [PMID: 30038612 PMCID: PMC6046465 DOI: 10.3389/fimmu.2018.01531] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2018] [Accepted: 06/20/2018] [Indexed: 12/11/2022] Open
Abstract
The release of damage-associated molecular patterns, including uridine triphosphate (UTP) and adenosine triphosphate (ATP) to the extracellular milieu is a key component of innate immune response to infection. Previously, we showed that macrophage infection by the protozoan parasite Leishmania amazonensis—the etiological agent of cutaneous leishmaniasis—can be controlled by ATP- and UTP-mediated activation of P2Y and P2X7 receptors (activated by UTP/ATP and ATP, respectively), which provided comparable immune responses against the parasite. Interestingly, in context of Leishmania amazonensis infection, UTP/P2Y triggered apoptosis, reactive oxygen species, and oxide nitric (NO) production, which are characteristic of P2X7 receptor activation. Here, we examined a possible “cross-talk” between P2Y2 and P2X7 receptors, and the requirement for pannexin-1 (PANX-1) in the control of L. amazonensis infection in mouse peritoneal macrophages and in vivo. UTP treatment reduced L. amazonensis parasite load, induced extracellular ATP release [which was pannexin-1 (PANX-1) dependent], and triggered leukotriene B4 (LTB4) production in macrophages. UTP-induced parasite control was blocked by pharmacological antagonism of P2Y2 or P2X7 receptors and was absent in macrophages lacking P2X7 or PANX-1. In addition, ATP release induced by UTP was also inhibited by PANX-1 blocker carbenoxolone, and partially reversed by inhibitors of vesicle traffic and actin cytoskeleton dynamics. In vivo, UTP treatment reduced footpad and popliteal lymph node parasite load, and the lesion in wild-type (WT) mice; fact not observed in P2X7−/− mice. Our data reveal that P2Y2 and P2X7 receptors cooperate to trigger potent innate immune responses against L. amazonensis infection.
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Affiliation(s)
- Maria Luiza Thorstenberg
- Laboratório de Imunofisiologia, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Marcos Vinícius Rangel Ferreira
- Laboratório de Imunofisiologia, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Natália Amorim
- Laboratório de inflamação, Instituto de Biofísica Carlos Chagas Filho, Rio de Janeiro, Brazil
| | - Claudio Canetti
- Laboratório de inflamação, Instituto de Biofísica Carlos Chagas Filho, Rio de Janeiro, Brazil
| | - Fernanda B Morrone
- Laboratório de Farmacologia Aplicada, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, Brazil
| | - José Carlos Alves Filho
- Departamento de Farmacologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Robson Coutinho-Silva
- Laboratório de Imunofisiologia, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
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48
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Young CNJ, Górecki DC. P2RX7 Purinoceptor as a Therapeutic Target-The Second Coming? Front Chem 2018; 6:248. [PMID: 30003075 PMCID: PMC6032550 DOI: 10.3389/fchem.2018.00248] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Accepted: 06/08/2018] [Indexed: 12/22/2022] Open
Abstract
The P2RX7 receptor is a unique member of a family of extracellular ATP (eATP)-gated ion channels expressed in immune cells, where its activation triggers the inflammatory cascade. Therefore, P2RX7 has been long investigated as a target in the treatment of infectious and inflammatory diseases. Subsequently, P2RX7 signaling has been documented in other physiological and pathological processes including pain, CNS and psychiatric disorders and cancer. As a result, a range of P2RX7 antagonists have been developed and trialed. Interestingly, the recent crystallization of mammalian and chicken receptors revealed that most widely-used antagonists may bind a unique allosteric site. The availability of crystal structures allows rational design of improved antagonists and modeling of binding sites of the known or presumed inhibitors. However, several unanswered questions limit the cogent development of P2RX7 therapies. Firstly, this receptor functions as an ion channel, but its chronic stimulation by high eATP causes opening of the non-selective large pore (LP), which can trigger cell death. Not only the molecular mechanism of LP opening is still not fully understood but its function(s) are also unclear. Furthermore, how can tumor cells take advantage of P2RX7 for growth and spread and yet survive overexpression of potentially cytotoxic LP in the eATP-rich environment? The recent discovery of the feedback loop, wherein the LP-evoked release of active MMP-2 triggers the receptor cleavage, provided one explanation. Another mechanism might be that of cancer cells expressing a structurally altered P2RX7 receptor, devoid of the LP function. Exploiting such mechanisms should lead to the development of new, less toxic anticancer treatments. Notably, targeted inhibition of P2RX7 is crucial as its global blockade reduces the immune and inflammatory responses, which have important anti-tumor effects in some types of malignancies. Therefore, another novel approach is the synthesis of tissue/cell specific P2RX7 antagonists. Progress has been aided by the development of p2rx7 knockout mice and new conditional knock-in and knock-out models are being created. In this review, we seek to summarize the recent advances in our understanding of molecular mechanisms of receptor activation and inhibition, which cause its re-emergence as an important therapeutic target. We also highlight the key difficulties affecting this development.
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Affiliation(s)
- Chris N. J. Young
- Molecular Medicine Laboratory, Institute of Biomedical and Biomolecular Sciences, School of Pharmacy and Biomedical Sciences, University of Portsmouth, Portsmouth, United Kingdom
- Faculty of Health and Life Sciences, The School of Allied Health Sciences, De Montfort University, Leicester, United Kingdom
| | - Dariusz C. Górecki
- Molecular Medicine Laboratory, Institute of Biomedical and Biomolecular Sciences, School of Pharmacy and Biomedical Sciences, University of Portsmouth, Portsmouth, United Kingdom
- The General Karol Kaczkowski Military Institute of Hygiene and Epidemiology, Warsaw, Poland
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49
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Purinergic modulation of frog electroretinographic responses: The role of the ionotropic receptor P2X7. Vis Neurosci 2018; 34:E015. [PMID: 28965497 DOI: 10.1017/s0952523817000128] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The contribution of the purinergic receptors P2X7 (P2X7Rs) to the electroretinographic (ERG) responses was studied by testing the effects of the selective P2X7R antagonist A438079 and the selective P2X7R agonist Bz-ATP on the electroretinograms obtained in perfused frog (Rana ridibunda) eyecup preparations under a variety of stimulation conditions. The P2X7R blockade by 200 µM A438079 diminished the amplitude of the photoreceptor components: the a-wave and the pharmacologically isolated mass receptor potential. In the pure rod-driven and pure cone-driven responses, the amplitude of the postreceptoral ON (b-wave) and OFF (d-wave) components was also diminished. The OFF responses were affected to a greater extent compared to the ON responses. In the mixed rod- and cone-driven responses, obtained in the mesopic intensity range, the b-wave amplitude was increased, while the d-wave amplitude was decreased. The amplitude of the oscillatory potentials was diminished. The relative amplitude changes produced by the P2X7R blockade were greater in the dark-adapted compared to the light-adapted eyes. The application of 100 µM Bz-ATP produced small effects opposite to those of the antagonist, while a prolonged (>20 min) treatment with 1 mM Bz-ATP resulted in a significant amplitude reduction or even abolishment of b- and d-waves. Our results show that endogenous ATP through its P2X7Rs exerts significant, mostly potentiating effects on the ERG photoreceptor and postreceptoral responses. There is a clear ON/OFF asymmetry of the effects on the ERG postreceptoral responses favoring OFF responses: they are always strongly potentiated, while the ON responses are either less potentiated (in the rod-driven and most of the cone-driven responses) or even inhibited (in the mixed rod- and cone-driven responses). The overstimulation of P2X7Rs can produce acute pathological changes, that is, a decrease or abolishment of the ERG responses.
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50
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Savio LEB, de Andrade Mello P, da Silva CG, Coutinho-Silva R. The P2X7 Receptor in Inflammatory Diseases: Angel or Demon? Front Pharmacol 2018; 9:52. [PMID: 29467654 PMCID: PMC5808178 DOI: 10.3389/fphar.2018.00052] [Citation(s) in RCA: 283] [Impact Index Per Article: 47.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 01/15/2018] [Indexed: 12/13/2022] Open
Abstract
Under physiological conditions, adenosine triphosphate (ATP) is present at low levels in the extracellular milieu, being massively released by stressed or dying cells. Once outside the cells, ATP and related nucleotides/nucleoside generated by ectonucleotidases mediate a high evolutionary conserved signaling system: the purinergic signaling, which is involved in a variety of pathological conditions, including inflammatory diseases. Extracellular ATP has been considered an endogenous adjuvant that can initiate inflammation by acting as a danger signal through the activation of purinergic type 2 receptors-P2 receptors (P2Y G-protein coupled receptors and P2X ligand-gated ion channels). Among the P2 receptors, the P2X7 receptor is the most extensively studied from an immunological perspective, being involved in both innate and adaptive immune responses. P2X7 receptor activation induces large-scale ATP release via its intrinsic ability to form a membrane pore or in association with pannexin hemichannels, boosting purinergic signaling. ATP acting via P2X7 receptor is the second signal to the inflammasome activation, inducing both maturation and release of pro-inflammatory cytokines, such as IL-1β and IL-18, and the production of reactive nitrogen and oxygen species. Furthermore, the P2X7 receptor is involved in caspases activation, as well as in apoptosis induction. During adaptive immune response, P2X7 receptor modulates the balance between the generation of T helper type 17 (Th17) and T regulatory (Treg) lymphocytes. Therefore, this receptor is involved in several inflammatory pathological conditions. In infectious diseases and cancer, P2X7 receptor can have different and contrasting effects, being an angel or a demon depending on its level of activation, cell studied, type of pathogen, and severity of infection. In neuroinflammatory and neurodegenerative diseases, P2X7 upregulation and function appears to contribute to disease progression. In this review, we deeply discuss P2X7 receptor dual function and its pharmacological modulation in the context of different pathologies, and we also highlight the P2X7 receptor as a potential target to treat inflammatory related diseases.
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Affiliation(s)
- Luiz E B Savio
- Laboratory of Immunophysiology, Biophysics Institute Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Paola de Andrade Mello
- Division of Gastroenterology, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Harvard University, Boston, MA, United States
| | - Cleide Gonçalves da Silva
- Division of Vascular Surgery, Department of Surgery, Center for Vascular Biology Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States
| | - Robson Coutinho-Silva
- Laboratory of Immunophysiology, Biophysics Institute Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
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