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Ito MA, Kojima E, Yanagihara Y, Yoshida K, Matsuoka I. Differential Effects of Gq Protein-Coupled Uridine Receptor Stimulation on IL-8 Production in 1321N1 Human Astrocytoma Cells. Biol Pharm Bull 2022; 45:691-697. [PMID: 35650097 DOI: 10.1248/bpb.b21-01020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
G-protein-coupled receptors (GPCRs) trigger various physiological functions. GPCR-mediated effects largely depend on the receptor-associated G-protein subtypes. However, compelling evidence suggests that single receptor proteins activate multiple G-protein subtypes to induce diverse physiological responses. This study compared responses mediated by three different Gq-binding uridine nucleotide receptors, P2Y2, P2Y4, and P2Y6, by measuring Ca2+ signaling and interleukin (IL)-8 production. In 1321N1 human astrocytoma cells stably expressing these receptors, agonist stimulation evoked concentration-dependent intracellular Ca2+ elevation to a similar extent. In contrast, agonist-induced IL-8 production was prominent in P2Y6-expressing cells, but not in P2Y2- and P2Y4-expressing cells. In addition to inhibition of Gq signaling, G12 signal blockade attenuated uridine 5'-diphosphate (UDP)-induced IL-8 production, suggesting the involvement of a small G-protein pathway. The Rac inhibitor EHop-16 prevented UDP-induced IL-8 release. The P2Y6-triggered IL-8 production was also inhibited by extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and protein kinase B (Akt) inhibitors. These results suggest that P2Y6 receptor-induced IL-8 production requires Gq-mediated Ca2+ signaling as well as G12-mediated activation of Rac. The results also suggest the importance of considering the involvement of multiple G proteins in understanding GPCR-mediated functions.
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Affiliation(s)
- Masa-Aki Ito
- Laboratory of Pharmacology, Faculty of Pharmacy, Takasaki University of Health and Welfare
| | - Erika Kojima
- Laboratory of Pharmacology, Faculty of Pharmacy, Takasaki University of Health and Welfare
| | - Yu Yanagihara
- Laboratory of Pharmacology, Faculty of Pharmacy, Takasaki University of Health and Welfare
| | - Kazuki Yoshida
- Laboratory of Pharmacology, Faculty of Pharmacy, Takasaki University of Health and Welfare
| | - Isao Matsuoka
- Laboratory of Pharmacology, Faculty of Pharmacy, Takasaki University of Health and Welfare
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Obayashi K, Yoshida K, Ito MA, Mori T, Yamamoto K, Imai T, Matsuoka I. Synergistic Cytokine Production by ATP and PGE2 via P2X4 and EP3 Receptors in Mouse Bone-Marrow-Derived Mast Cells. Cells 2022; 11:cells11040616. [PMID: 35203267 PMCID: PMC8870111 DOI: 10.3390/cells11040616] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 02/07/2022] [Accepted: 02/08/2022] [Indexed: 12/31/2022] Open
Abstract
ATP is an important intercellular messenger in the extracellular space. In mast cells (MCs), ATP stimulates the ionotropic P2X4 receptor (P2X4R), resulting in enhanced degranulation and exacerbation of acute allergic reactions. In this study, we investigate whether ATP regulates inflammatory cytokine production in MCs. Gene expression was analyzed by quantitative RT-PCR, and cytokine production was measured using ELISA. The stimulation of mouse bone-marrow-derived MCs (BMMCs) with ATP alone had little effect on cytokine secretion. However, the co-stimulation with prostaglandin (PG) E2 resulted in a marked increase in the secretion of various cytokines, such as tumor necrosis factor-α, interleukin (IL)-6, and IL-13, accompanied by an increase in their mRNA levels. The effects of ATP were inhibited by P2X4R antagonists and diminished in BMMCs derived from P2X4R-deficient mice, suggesting that P2X4R mediated the reaction. The effects of PGE2 were mimicked by an EP3 receptor (EP3R) agonist and blocked by an EP3R antagonist. The synergistic cytokine mRNA elevations induced by ATP and PGE2 were blocked by nuclear factor-κB and Ca2+-calcineurin signaling inhibitors. Altogether, these results suggest that combining P2X4R and EP3R signaling enhances acute degranulation and the subsequent cytokine secretion, exacerbating allergic inflammation.
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Affiliation(s)
- Kosuke Obayashi
- Laboratory of Pharmacology, Faculty of Pharmacy, Takasaki University of Health and Welfare, Takasaki 370-0033, Gunma, Japan; (K.O.); (K.Y.); (M.-a.I.)
| | - Kazuki Yoshida
- Laboratory of Pharmacology, Faculty of Pharmacy, Takasaki University of Health and Welfare, Takasaki 370-0033, Gunma, Japan; (K.O.); (K.Y.); (M.-a.I.)
| | - Masa-aki Ito
- Laboratory of Pharmacology, Faculty of Pharmacy, Takasaki University of Health and Welfare, Takasaki 370-0033, Gunma, Japan; (K.O.); (K.Y.); (M.-a.I.)
| | - Tetsuya Mori
- Laboratory of Allergy and Immunology, Faculty of Pharmacy, Takasaki University of Health and Welfare, Takasaki 370-0033, Gunma, Japan;
| | - Kimiko Yamamoto
- Department of Biomedical Engineering, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan;
| | - Toshiyashu Imai
- Discovery Research Laboratories, Nippon Chemiphar Co., Ltd., Misato 341-0005, Saitama, Japan;
| | - Isao Matsuoka
- Laboratory of Pharmacology, Faculty of Pharmacy, Takasaki University of Health and Welfare, Takasaki 370-0033, Gunma, Japan; (K.O.); (K.Y.); (M.-a.I.)
- Correspondence: ; Tel.: +81-27-352-1180
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Microglia Purinoceptor P2Y6: An Emerging Therapeutic Target in CNS Diseases. Cells 2020; 9:cells9071595. [PMID: 32630251 PMCID: PMC7407337 DOI: 10.3390/cells9071595] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 06/24/2020] [Accepted: 06/29/2020] [Indexed: 12/14/2022] Open
Abstract
The purinergic receptor P2Y6 is expressed in immune cells, including the microglia that are implicated in neurological disorders. Its ligand, UDP, is a signaling molecule that can serve as an “find-me” signal when released in significant quantities by damaged/dying cells. The binding of UDP by P2Y6R leads to the activation of different biochemical pathways, depending on the disease context and the pathological environment. Generally, P2Y6R stimulates phagocytosis. However, whether or not phagocytosis coincides with cell activation or the secretion of pro-inflammatory cytokines needs further investigation. The current review aims to discuss the various functions of P2Y6R in some CNS disorders. We present evidence that P2Y6R may have a detrimental or beneficial role in the nervous system, in the context of neurological pathologies, such as ischemic stroke, Alzheimer’s disease, Parkinson’s disease, radiation-induced brain injury, and neuropathic pain.
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The role of P2Y 6R in cardiovascular diseases and recent development of P2Y 6R antagonists. Drug Discov Today 2020; 25:568-573. [PMID: 31926135 DOI: 10.1016/j.drudis.2019.12.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 11/19/2019] [Accepted: 12/30/2019] [Indexed: 11/21/2022]
Abstract
As a member of the P2Y receptor family with a typical 7-transmembrane structure, P2Y6 purinergic receptor (P2Y6R) belongs to the G-protein-coupled nucleotide receptor activating the phospholipase-C signaling pathway. P2Y6R is widely involved in a range of human diseases, including atherosclerosis and other cardiovascular diseases, gradually attracting attention owing to its inappropriate or excessive activation. In addition, it was reported that P2Y6R might regulate inflammatory responses by governing the maturation and secretion of proinflammatory cytokines. Hence, several P2Y6R antagonists have been subjected to evaluation as new therapeutic strategies in recent years. This review was aimed at summarizing the role of P2Y6R in the pathogenesis of cardiovascular diseases, with an insight into the recent progress on discovery of P2Y6R antagonists.
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Yoshida K, Tajima M, Nagano T, Obayashi K, Ito M, Yamamoto K, Matsuoka I. Co-Stimulation of Purinergic P2X4 and Prostanoid EP3 Receptors Triggers Synergistic Degranulation in Murine Mast Cells. Int J Mol Sci 2019; 20:E5157. [PMID: 31627451 PMCID: PMC6829402 DOI: 10.3390/ijms20205157] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 10/16/2019] [Accepted: 10/16/2019] [Indexed: 01/21/2023] Open
Abstract
Mast cells (MCs) recognize antigens (Ag) via IgE-bound high affinity IgE receptors (FcεRI) and trigger type I allergic reactions. FcεRI-mediated MC activation is regulated by various G protein-coupled receptor (GPCR) agonists. We recently reported that ionotropic P2X4 receptor (P2X4R) stimulation enhanced FcεRI-mediated degranulation. Since MCs are involved in Ag-independent hypersensitivity, we investigated whether co-stimulation with ATP and GPCR agonists in the absence of Ag affects MC degranulation. Prostaglandin E2 (PGE2) induced synergistic degranulation when bone marrow-derived MCs (BMMCs) were co-stimulated with ATP, while pharmacological analyses revealed that the effects of PGE2 and ATP were mediated by EP3 and P2X4R, respectively. Consistently, this response was absent in BMMCs prepared from P2X4R-deficient mice. The effects of ATP and PGE2 were reduced by PI3 kinase inhibitors but were insensitive to tyrosine kinase inhibitors which suppressed the enhanced degranulation induced by Ag and ATP. MC-dependent PGE2-triggered vascular hyperpermeability was abrogated in a P2X4R-deficient mouse ear edema model. Collectively, our results suggest that P2X4R signaling enhances EP3R-mediated MC activation via a different mechanism to that involved in enhancing Ag-induced responses. Moreover, the cooperative effects of the common inflammatory mediators ATP and PGE2 on MCs may be involved in Ag-independent hypersensitivity in vivo.
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Affiliation(s)
- Kazuki Yoshida
- Laboratory of Pharmacology, Faculty of Pharmacy, Takasaki University of Health and Welfare, Takasaki-shi, Gunma 370-0033, Japan.
| | - Makoto Tajima
- Laboratory of Pharmacology, Faculty of Pharmacy, Takasaki University of Health and Welfare, Takasaki-shi, Gunma 370-0033, Japan.
| | - Tomoki Nagano
- Laboratory of Pharmacology, Faculty of Pharmacy, Takasaki University of Health and Welfare, Takasaki-shi, Gunma 370-0033, Japan.
| | - Kosuke Obayashi
- Laboratory of Pharmacology, Faculty of Pharmacy, Takasaki University of Health and Welfare, Takasaki-shi, Gunma 370-0033, Japan.
| | - Masaaki Ito
- Laboratory of Pharmacology, Faculty of Pharmacy, Takasaki University of Health and Welfare, Takasaki-shi, Gunma 370-0033, Japan.
| | - Kimiko Yamamoto
- Department of Biomedical Engineering, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan.
| | - Isao Matsuoka
- Laboratory of Pharmacology, Faculty of Pharmacy, Takasaki University of Health and Welfare, Takasaki-shi, Gunma 370-0033, Japan.
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Alarcón-Vila C, Pizzuto M, Pelegrín P. Purinergic receptors and the inflammatory response mediated by lipids. Curr Opin Pharmacol 2019; 47:90-96. [PMID: 30952060 DOI: 10.1016/j.coph.2019.02.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 02/15/2019] [Accepted: 02/18/2019] [Indexed: 02/07/2023]
Abstract
The inflammatory response is regulated by the production of different extracellular mediators, including lipids and extracellular nucleotides. In the extracellular environment, intermediate lipids activate specific G-protein-coupled receptors (GPCRs) in target cells and promote cell recruitment and activation. Extracellular nucleotides activate two types of receptors, the ionotropic purinergic P2X and the metabotropic purinergic P2Y receptors, inducing the release of cytokines and promoting cell recruitment. Several P2X receptors are associated with an increase in the production of immunoactive lipids mediators, which in turn are able to interfere with the activation of different P2Y receptors, establishing a tight signalling link between purinergic receptors and lipid mediators. In this review, we summarise recent studies indicating signalling crosstalk between purinergic P2X and P2Y receptor activation and lipid mediators with a focus on inflammatory diseases. Novel concepts arising from this crosstalk would result in the development of combinatorial therapies targeting lipid synthesis together with individual P2 receptors for the management of inflammatory diseases.
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Affiliation(s)
- Cristina Alarcón-Vila
- Instituto Murciano de Investigación Biosanitaria IMIB-Arrixaca, Hospital Clínico Universitario Virgen de la Arrixaca, Murcia, Spain
| | - Malvina Pizzuto
- Instituto Murciano de Investigación Biosanitaria IMIB-Arrixaca, Hospital Clínico Universitario Virgen de la Arrixaca, Murcia, Spain
| | - Pablo Pelegrín
- Instituto Murciano de Investigación Biosanitaria IMIB-Arrixaca, Hospital Clínico Universitario Virgen de la Arrixaca, Murcia, Spain.
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Lu SM, Fairn GD. 7-Ketocholesterol impairs phagocytosis and efferocytosis via dysregulation of phosphatidylinositol 4,5-bisphosphate. Traffic 2018; 19:591-604. [PMID: 29693767 DOI: 10.1111/tra.12576] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Revised: 04/16/2018] [Accepted: 04/18/2018] [Indexed: 12/27/2022]
Abstract
The plasma membrane is inhomogeneously organized containing both highly ordered and disordered nanodomains. 7-Ketocholesterol (7KC), an oxysterol formed from the nonenzymatic oxidation of cholesterol, is a potent disruptor of membrane order. Importantly, 7KC is a component of oxidized low-density lipoprotein and accumulates in macrophage and foam cells found in arterial plaques. Using a murine macrophage cell line, J774, we report that both IgG-mediated and phosphatidylserine-mediated phagocytic pathways are inhibited by the accumulation of 7KC. Examination of the well-studied Fcγ receptor pathway revealed that the cell surface receptor abundance and ligand binding are unaltered while downstream signaling and activation of spleen tyrosine kinase is not affected. However, while the recruitment of phospholipase Cγ1 was unaffected its apparent enzymatic activity was compromised resulting in sustained phosphatidylinositol 4,5-bisphosphate [PtdIns(4,5)P2 ] levels and polymerized actin at the base of the phagocytic cup. Additionally, we found that 7KC prevented the activation of PLCβ downstream of the P2Y6 G-protein coupled receptor and that 7KC impaired PLCγ activity in response to a direct elevation of cytosolic calcium induced by ionomycin. Finally, we demonstrate that 7KC partly attenuates the activity of rapamycin recruitable constitutively active PLCβ3. Together, our results demonstrate that the accumulation of 7KC impairs macrophage function by altering PtdIns(4,5)P2 catabolism and, thus, impairing actin depolymerization required for the completion of phagocytosis.
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Affiliation(s)
- Stella M Lu
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada.,Keenan Research Centre for Biomedical Sciences, St. Michael's Hospital, Toronto, ON, Canada
| | - Gregory D Fairn
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada.,Keenan Research Centre for Biomedical Sciences, St. Michael's Hospital, Toronto, ON, Canada.,Department of Surgery and Institute of Medical Science, University of Toronto, Toronto, ON, Canada
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8
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Shinozaki Y, Kashiwagi K, Namekata K, Takeda A, Ohno N, Robaye B, Harada T, Iwata T, Koizumi S. Purinergic dysregulation causes hypertensive glaucoma-like optic neuropathy. JCI Insight 2017; 2:93456. [PMID: 28978804 DOI: 10.1172/jci.insight.93456] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Accepted: 08/24/2017] [Indexed: 12/24/2022] Open
Abstract
Glaucoma is an optic neuropathy characterized by progressive degeneration of retinal ganglion cells (RGCs) and visual loss. Although one of the highest risk factors for glaucoma is elevated intraocular pressure (IOP) and reduction in IOP is the only proven treatment, the mechanism of IOP regulation is poorly understood. We report that the P2Y6 receptor is critical for lowering IOP and that ablation of the P2Y6 gene in mice (P2Y6KO) results in hypertensive glaucoma-like optic neuropathy. Topically applied uridine diphosphate, an endogenous selective agonist for the P2Y6 receptor, decreases IOP. The P2Y6 receptor was expressed in nonpigmented epithelial cells of the ciliary body and controlled aqueous humor dynamics. P2Y6KO mice exhibited sustained elevation of IOP, age-dependent damage to the optic nerve, thinning of ganglion cell plus inner plexiform layers, and a reduction of RGC numbers. These changes in P2Y6KO mice were attenuated by an IOP lowering agent. Consistent with RGC damage, visual functions were impaired in middle-aged P2Y6KO mice. We also found that expression and function of P2Y6 receptors in WT mice were significantly reduced by aging, another important risk factor for glaucoma. In summary, our data show that dysfunctional purinergic signaling causes IOP dysregulation, resulting in glaucomatous optic neuropathy.
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Affiliation(s)
- Youichi Shinozaki
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, and
| | - Kenji Kashiwagi
- Department of Ophthalmology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Yamanashi, Japan
| | - Kazuhiko Namekata
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Akiko Takeda
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, and
| | - Nobuhiko Ohno
- Division of Neurobiology and Bioinformatics, National Institute for Physiological Sciences, Okazaki, Aichi, Japan
| | - Bernard Robaye
- Institute of Interdisciplinary Research and.,Institute of Biology and Molecular Medicine, Université Libre de Bruxelles, Belgium
| | - Takayuki Harada
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Takeshi Iwata
- Division of Molecular and Cellular Biology, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, Japan
| | - Schuichi Koizumi
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, and
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Paniagua-Herranz L, Gil-Redondo JC, Queipo MJ, González-Ramos S, Boscá L, Pérez-Sen R, Miras-Portugal MT, Delicado EG. Prostaglandin E 2 Impairs P2Y 2/P2Y 4 Receptor Signaling in Cerebellar Astrocytes via EP3 Receptors. Front Pharmacol 2017; 8:937. [PMID: 29311938 PMCID: PMC5743739 DOI: 10.3389/fphar.2017.00937] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 12/11/2017] [Indexed: 02/05/2023] Open
Abstract
Prostaglandin E2 (PGE2) is an important bioactive lipid that accumulates after tissue damage or inflammation due to the rapid expression of cyclooxygenase 2. PGE2 activates specific G-protein coupled EP receptors and it mediates pro- or anti-inflammatory actions depending on the cell-context. Nucleotides can also be released in these situations and they even contribute to PGE2 production. We previously described the selective impairment of P2Y nucleotide signaling by PGE2 in macrophages and fibroblasts, an effect independent of prostaglandin receptors but that involved protein kinase C (PKC) and protein kinase D (PKD) activation. Considering that macrophages and fibroblasts influence inflammatory responses and tissue remodeling, a similar mechanism involving P2Y signaling could occur in astrocytes in response to neuroinflammation and brain repair. We analyzed here the modulation of cellular responses involving P2Y2/P2Y4 receptors by PGE2 in rat cerebellar astrocytes. We demonstrate that PGE2 inhibits intracellular calcium responses elicited by UTP in individual cells and that inhibiting this P2Y signaling impairs the astrocyte migration elicited by this nucleotide. Activation of EP3 receptors by PGE2 not only impairs the calcium responses but also, the extracellular regulated kinases (ERK) and Akt phosphorylation induced by UTP. However, PGE2 requires epidermal growth factor receptor (EGFR) transactivation in order to dampen P2Y signaling. In addition, these effects of PGE2 also occur in a pro-inflammatory context, as evident in astrocytes stimulated with bacterial lipopolysaccharide (LPS). While we continue to investigate the intracellular mechanisms responsible for the inhibition of UTP responses, the involvement of novel PKC and PKD in cerebellar astrocytes cannot be excluded, kinases that could promote the internalization of P2Y receptors in fibroblasts.
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Yoshida K, Ito M, Matsuoka I. Divergent regulatory roles of extracellular ATP in the degranulation response of mouse bone marrow-derived mast cells. Int Immunopharmacol 2016; 43:99-107. [PMID: 27988461 DOI: 10.1016/j.intimp.2016.12.014] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Revised: 11/25/2016] [Accepted: 12/09/2016] [Indexed: 02/06/2023]
Abstract
Mast cells (MCs) play a critical role in allergic inflammation. Although purinergic signalling is implicated in the regulation of various immune responses, its role in MC function is not fully understood. In this study, we investigated the regulatory role of purinergic signalling in MC degranulation, using mouse bone marrow-derived mast cells (BMMCs). Notably, BMMCs expressed various functional P2 adenosine triphosphate (ATP) receptors, including ionotropic P2X4 and P2X7, involved in the regulation of BMMC degranulation. Thus, P2X7 receptor activation induced a marked degranulation from BMMCs directly. Although P2X4 receptor activation did not independently induce degranulation, it significantly potentiated the degranulation triggered by antigen-induced, high-affinity IgE receptor (FcεRI) stimulation. In addition, ATP synergistically augmented degranulation induced by adenosine A3 receptor activation. Moreover, BMMCs highly expressed ecto-nucleotidase CD39, but not ecto-5'-nucleotidase (CD73), and were therefore unable to directly convert ATP to adenosine. However, in the presence of CD73-expressing cells, ATP-mediated BMMC stimulation caused a marked degranulation in a CD73- and adenosine-dependent manner. These results demonstrate that purinergic signalling plays an important role in MC degranulation through at least three distinct mechanisms: (1) higher ATP concentrations directly induce degranulation via P2X7 receptor activation, (2) lower ATP concentrations augment FcεRI-mediated degranulation via P2X4 receptor activation, and (3) in an ecto-nucleotidase-enrich environment, ATP and the converted product adenosine induce a synergistic degranulation by P1 and P2 receptor co-activation.
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Affiliation(s)
- Kazuki Yoshida
- Laboratory of Pharmacology, Faculty of Pharmacy, Takasaki University of Health and Welfare, 60 Nakaorui-machi, Takasaki-shi, Gunma 370-0033, Japan
| | - Masaaki Ito
- Laboratory of Pharmacology, Faculty of Pharmacy, Takasaki University of Health and Welfare, 60 Nakaorui-machi, Takasaki-shi, Gunma 370-0033, Japan
| | - Isao Matsuoka
- Laboratory of Pharmacology, Faculty of Pharmacy, Takasaki University of Health and Welfare, 60 Nakaorui-machi, Takasaki-shi, Gunma 370-0033, Japan.
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