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Madaan P, Behl T, Sehgal A, Singh S, Sharma N, Yadav S, Kaur S, Bhatia S, Al-Harrasi A, Abdellatif AAH, Ashraf GM, Abdel-Daim MM, Dailah HG, Anwer MK, Bungau S. Exploring the Therapeutic Potential of Targeting Purinergic and Orexinergic Receptors in Alcoholic Neuropathy. Neurotox Res 2022; 40:646-669. [DOI: 10.1007/s12640-022-00477-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 01/13/2022] [Accepted: 01/19/2022] [Indexed: 12/11/2022]
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Cai X, Yao Y, Teng F, Li Y, Wu L, Yan W, Lin N. The role of P2X7 receptor in infection and metabolism: Based on inflammation and immunity. Int Immunopharmacol 2021; 101:108297. [PMID: 34717202 DOI: 10.1016/j.intimp.2021.108297] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Revised: 10/15/2021] [Accepted: 10/19/2021] [Indexed: 12/20/2022]
Abstract
The P2X7 receptor (P2X7R) is a ligand-gated receptor belonging to the P2 receptor family. It is distributed in various tissues of the human body and is involved in regulating the physiological functions of tissues and cells to affect the occurrence and development of diseases. Unlike all other P2 receptors, the P2X7 receptor is mainly expressed in immune cells and can be activated not only by extracellular nucleotides but also by non-nucleotide substances which act as positive allosteric modulators. In this review, we comprehensively describe the role of the P2X7 receptor in infection and metabolism based on its role as an important regulator of inflammation and immunity, and briefly introduce the structure and general function of the P2X7 receptor. These provide a clear knowledge framework for the study of the P2X7 receptor in human health. Targeting the P2X7 receptor may be an effective method for the treatment of inflammatory and immune diseases. And its role in microbial infection and metabolism may be the main direction for in-depth research on the P2X7 receptor in the future.
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Affiliation(s)
- Xiaoyu Cai
- Department of Clinical Pharmacology, Key Laboratory of Clinical Cancer Pharmacology and Toxicology Research of Zhejiang Province, Affiliated Hangzhou First People's Hospital, Cancer Center, Zhejiang University School of Medicine, Hangzhou 310006, China
| | - Yao Yao
- Department of Pharmacy, Women's Hospital School of Medicine Zhejiang University, Hangzhou 310006, China
| | - Fei Teng
- College of Pharmaceutical Sciences, Zhejiang Chinese Medical University, Hangzhou 310053, China
| | - Yangling Li
- Department of Clinical Pharmacology, Key Laboratory of Clinical Cancer Pharmacology and Toxicology Research of Zhejiang Province, Affiliated Hangzhou First People's Hospital, Cancer Center, Zhejiang University School of Medicine, Hangzhou 310006, China
| | - Linwen Wu
- Department of Clinical Pharmacology, Key Laboratory of Clinical Cancer Pharmacology and Toxicology Research of Zhejiang Province, Affiliated Hangzhou First People's Hospital, Cancer Center, Zhejiang University School of Medicine, Hangzhou 310006, China
| | - Wei Yan
- Department of Clinical Pharmacology, Key Laboratory of Clinical Cancer Pharmacology and Toxicology Research of Zhejiang Province, Affiliated Hangzhou First People's Hospital, Cancer Center, Zhejiang University School of Medicine, Hangzhou 310006, China.
| | - Nengming Lin
- Department of Clinical Pharmacology, Key Laboratory of Clinical Cancer Pharmacology and Toxicology Research of Zhejiang Province, Affiliated Hangzhou First People's Hospital, Cancer Center, Zhejiang University School of Medicine, Hangzhou 310006, China; College of Pharmaceutical Sciences, Zhejiang Chinese Medical University, Hangzhou 310053, China.
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Territo PR, Zarrinmayeh H. P2X 7 Receptors in Neurodegeneration: Potential Therapeutic Applications From Basic to Clinical Approaches. Front Cell Neurosci 2021; 15:617036. [PMID: 33889073 PMCID: PMC8055960 DOI: 10.3389/fncel.2021.617036] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 03/02/2021] [Indexed: 12/27/2022] Open
Abstract
Purinergic receptors play important roles in central nervous system (CNS), where the bulk of these receptors are implicated in neuroinflammatory responses and regulation of cellular function of neurons, microglial and astrocytes. Within the P2X receptor family, P2X7 receptor is generally known for its inactivity in normal conditions and activation by moderately high concentrations (>100 μM) of extracellular adenosine 5′-triphosphate (ATP) released from injured cells as a result of brain injury or pathological conditions. Activation of P2X7R contributes to the activation and proliferation of microglia and directly contribute to neurodegeneration by provoking microglia-mediated neuronal death, glutamate-mediated excitotoxicity, and NLRP3 inflammasome activation that results in initiation, maturity and release of the pro-inflammatory cytokines and generation of reactive oxygen and nitrogen species. These components of the inflammatory response play important roles in many neural pathologies and neurodegeneration disorders. In CNS, expression of P2X7R on microglia, astrocytes, and oligodendrocytes are upregulated under neuroinflammatory conditions. Several in vivo studies have demonstrated beneficial effects of the P2X7 receptor antagonists in animal model systems of neurodegenerative diseases. A number of specific and selective P2X7 receptor antagonists have been developed, but only few of them have shown efficient brain permeability. Finding potent and selective P2X7 receptor inhibitors which are also CNS penetrable and display acceptable pharmacokinetics (PK) has presented challenges for both academic researchers and pharmaceutical companies. In this review, we discuss the role of P2X7 receptor function in neurodegenerative diseases, the pharmacological inhibition of the receptor, and PET radiopharmaceuticals which permit non-invasive monitoring of the P2X7 receptor contribution to neuroinflammation associated with neurodegeneration.
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Affiliation(s)
- Paul R Territo
- Department of Medicine, Indiana University School of Medicine, Indianapolis, IN, United States.,Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, IN, United States
| | - Hamideh Zarrinmayeh
- Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, IN, United States
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Tatsushima K, Hasuzawa N, Wang L, Hiasa M, Sakamoto S, Ashida K, Sudo N, Moriyama Y, Nomura M. Vesicular ATP release from hepatocytes plays a role in the progression of nonalcoholic steatohepatitis. Biochim Biophys Acta Mol Basis Dis 2021; 1867:166013. [PMID: 33212187 DOI: 10.1016/j.bbadis.2020.166013] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 11/03/2020] [Accepted: 11/09/2020] [Indexed: 12/18/2022]
Abstract
Non-alcoholic steatohepatitis (NASH) is becoming a growing public health problem along with the increase of metabolic syndrome worldwide. Extracellular nucleotides are known to serve as a danger signal by initiating purinergic signaling in many inflammatory disorders, although the role of purinergic signaling in the progression of NASH remains to be clarified. Vesicular nucleotide transporter (VNUT) is a key molecule responsible for vesicular ATP release to initiate purinergic signaling. Here, we studied the role of VNUT in the progression of nonalcoholic steatohepatitis. VNUT was expressed in mouse hepatocytes and associated, at least in part, with apolipoprotein B (apoB)-containing vesicles. High glucose stimulation evoked release of appreciable amount of ATP from hepatocytes, which disappeared in hepatocytes of Vnut knockout (Vnut-/-) mice. Glucose treatment also stimulated triglyceride secretion from hepatocytes, which was inhibited by PPADS and MRS211, antagonists of P2Y receptors, and clodronate, a VNUT inhibitor, and was significantly reduced in Vnut-/- mice. In vivo, postprandial secretion of triglyceride from hepatocytes was observed, while the serum triglyceride level was significantly reduced in Vnut-/- mice. On a high-fat diet, the liver of wild type mice exhibited severe inflammation, fibrosis, and macrophage infiltration, which is similar to NASH in humans, while this NASH pathology was not observed in Vnut-/- mice. These results suggest that VNUT-mediated vesicular ATP release regulates triglyceride secretion and involves in chronic inflammation in hepatocytes. Since blockade of vesicular ATP release protects against progression of steatohepatitis, VNUT may be a pharmacological target for NASH.
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Affiliation(s)
- Keita Tatsushima
- Department of Medicine and Bioregulatory Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan; Department of Psychosomatic Medicine, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan; Endocrine Center, Toranomon Hospital, Tokyo 105-8470, Japan
| | - Nao Hasuzawa
- Department of Medicine and Bioregulatory Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan; Division of Endocrinology and Metabolism, Department of Internal Medicine, Kurume University School of Medicine, Kurume 830-0011, Japan
| | - Lixiang Wang
- Department of Medical Biochemistry, Kurume University School of Medicine, Kurume 830-0011, Japan
| | - Miki Hiasa
- Department of Membrane Biochemistry, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama 700-8530, Japan
| | - Shohei Sakamoto
- Department of Medicine and Bioregulatory Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan
| | - Kenji Ashida
- Department of Medicine and Bioregulatory Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan; Division of Endocrinology and Metabolism, Department of Internal Medicine, Kurume University School of Medicine, Kurume 830-0011, Japan
| | - Nobuyuki Sudo
- Department of Psychosomatic Medicine, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan
| | - Yoshinori Moriyama
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Kurume University School of Medicine, Kurume 830-0011, Japan; Department of Membrane Biochemistry, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama 700-8530, Japan.
| | - Masatoshi Nomura
- Department of Medicine and Bioregulatory Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan; Division of Endocrinology and Metabolism, Department of Internal Medicine, Kurume University School of Medicine, Kurume 830-0011, Japan.
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Lan Y, Yang Z, Liu H, Cheng H, Liu S, Tan S. [PSB0739 inhibits formation of semen-derived amyloid fibril]. NAN FANG YI KE DA XUE XUE BAO = JOURNAL OF SOUTHERN MEDICAL UNIVERSITY 2019; 38:1338-1343. [PMID: 30514682 DOI: 10.12122/j.issn.1673-4254.2018.11.10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
OBJECTIVE To explore the inhibitory effect of PSB0739 on the formation of semen-derived amyloid fibrils. METHODS PAP248-286 (440 μmol/L) was incubated with PSB0739 at different concentrations, and at different time points of incubation, aliquots were taken from each sample for Congo red staining to detect the formation of amyloid fibers. The morphology of amyloid fibrils incubated in the presence or absence of PSB0739 was visualized using transmission electron microscope. The effect of PSB0739 on amyloid fibril formation was determined using virus infection assays at different time points, and the surface charges of amyloid fibril incubated with PSB0739 were calculated using a Zeta potentiometer. The cytotoxicity of PSB0739 in Hela cells was determined using MTT assay. The antiviral effect of PSB0738 against HIV- 1 was evaluated by infection assay. RESULTS PSB0739 inhibited SEVI fibril formation in a dose-dependent manner in vitro. At 48 h of incubation, 220 μmol/L of PSB0739 obviously inhibited the formation of amyloid fibrils in 440 μmol/L of SEVI. Transmission electron microscopy revealed that 220 μmol/L PSB0739 prevented PAP248- 286 (440 μmol/L) from forming amyloid fibrils. PSB0739 antagonized SEVI-mediated enhancement of HIV-1 infection, and 1760 μmol/L of PSB0739 completely reversed the positive charge of SEVI (P < 0.05). PSB0739 below the concentration of 62.5 μmol/L showed no obvious cytotoxicity in Hela cells in vitro (P>0.05). PSB0739 showed a direct anti-HIV activity with an IC50 of 21.77±5.15 μmol/L. CONCLUSIONS PSB0739 can inhibit the formation of semen-derived amyloid fibrils in vitro.
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Affiliation(s)
- Yan Lan
- School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China
| | - Zichao Yang
- School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China
| | - Han Liu
- School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China
| | - Hongyan Cheng
- School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China
| | - Shuwen Liu
- School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China
| | - Suiyi Tan
- School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China
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Moldovan RP, Wenzel B, Teodoro R, Neumann W, Dukic-Stefanovic S, Kraus W, Rong P, Deuther-Conrad W, Hey-Hawkins E, Krügel U, Brust P. Studies towards the development of a PET radiotracer for imaging of the P2Y 1 receptors in the brain: synthesis, 18F-labeling and preliminary biological evaluation. Eur J Med Chem 2019; 165:142-159. [PMID: 30665144 DOI: 10.1016/j.ejmech.2019.01.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Revised: 12/20/2018] [Accepted: 01/04/2019] [Indexed: 12/14/2022]
Abstract
Purine nucleotides such as ATP and ADP are important extracellular signaling molecules in almost all tissues activating various subtypes of purinoreceptors. In the brain, the P2Y1 receptor (P2Y1R) subtype mediates trophic functions like differentiation and proliferation, and modulates fast synaptic transmission, both suggested to be affected in diseases of the central nervous system. Research on P2Y1R is limited because suitable brain-penetrating P2Y1R-selective tracers are not yet available. Here, we describe the first efforts to develop an 18F-labeled PET tracer based on the structure of the highly affine and selective, non-nucleotidic P2Y1R allosteric modulator 1-(2-[2-(tert-butyl)phenoxy]pyridin-3-yl)-3-[4-(trifluoromethoxy)phenyl]urea (7). A small series of fluorinated compounds was developed by systematic modification of the p-(trifluoromethoxy)phenyl, the urea and the 2-pyridyl subunits of the lead compound 7. Additionally, the p-(trifluoromethoxy)phenyl subunit was substituted by carborane, a boron-rich cluster with potential applicability in boron neutron capture therapy (BNCT). By functional assays, the new fluorinated derivative 1-{2-[2-(tert-butyl)phenoxy]pyridin-3-yl}-3-[4-(2-fluoroethyl)phenyl]urea (18) was identified with a high P2Y1R antagonistic potency (IC50 = 10 nM). Compound [18F]18 was radiosynthesized by using tetra-n-butyl ammonium [18F]fluoride with high radiochemical purity, radiochemical yield and molar activities. Investigation of brain homogenates using hydrophilic interaction chromatography (HILIC) revealed [18F]fluoride as major radiometabolite. Although [18F]18 showed fast in vivo metabolization, the high potency and unique allosteric binding mode makes this class of compounds interesting for further optimizations and investigation of the theranostic potential as PET tracer and BNCT agent.
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Affiliation(s)
- Rareş-Petru Moldovan
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Permoserstraße 15, 04318, Leipzig, Germany.
| | - Barbara Wenzel
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Permoserstraße 15, 04318, Leipzig, Germany
| | - Rodrigo Teodoro
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Permoserstraße 15, 04318, Leipzig, Germany
| | - Wilma Neumann
- Institute of Inorganic Chemistry, Faculty of Chemistry and Mineralogy, Universität Leipzig, 04103, Leipzig, Germany
| | - Sladjana Dukic-Stefanovic
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Permoserstraße 15, 04318, Leipzig, Germany
| | - Werner Kraus
- BAM Federal Institute for Materials Research and Testing, Richard-Willstätter-Str. 11, 12489, Berlin, Germany
| | - Peijing Rong
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, 100700, Beijing, China
| | - Winnie Deuther-Conrad
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Permoserstraße 15, 04318, Leipzig, Germany
| | - Evamarie Hey-Hawkins
- Institute of Inorganic Chemistry, Faculty of Chemistry and Mineralogy, Universität Leipzig, 04103, Leipzig, Germany
| | - Ute Krügel
- Rudolf Boehm Institute of Pharmacology and Toxicology, Medical Faculty, Universität Leipzig, 04107, Leipzig, Germany
| | - Peter Brust
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Permoserstraße 15, 04318, Leipzig, Germany
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7
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P2Y2R is a direct target of HIF-1α and mediates secretion-dependent cyst growth of renal cyst-forming epithelial cells. Purinergic Signal 2016; 12:687-695. [PMID: 27565965 DOI: 10.1007/s11302-016-9532-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Accepted: 08/18/2016] [Indexed: 01/01/2023] Open
Abstract
Polycystic kidney diseases are characterized by numerous renal cysts that continuously enlarge resulting in compression of intact nephrons and tissue hypoxia. Recently, we have shown that hypoxia-inducible factor (HIF)-1α promotes secretion-dependent cyst expansion, presumably by transcriptional regulation of proteins that are involved in calcium-activated chloride secretion. Here, we report that HIF-1α directly activates expression of the purinergic receptor P2Y2R in human primary renal tubular cells. In addition, we found that P2Y2R is highly expressed in cyst-lining cells of human ADPKD kidneys as well as PKD1 orthologous mouse kidneys. Knockdown of P2Y2R in renal collecting duct cells inhibited calcium-dependent chloride secretion in Ussing chamber analyses. In line with these findings, knockdown of P2Y2R retarded cyst expansion in vitro and prevented ATP- and HIF-1α-dependent cyst growth. In conclusion, P2Y2R mediates ATP-dependent cyst growth and is transcriptionally regulated by HIF-1α. These findings provide further mechanistic evidence on how hypoxia promotes cyst growth.
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Förster D, Reiser G. Supportive or detrimental roles of P2Y receptors in brain pathology?--The two faces of P2Y receptors in stroke and neurodegeneration detected in neural cell and in animal model studies. Purinergic Signal 2015; 11:441-54. [PMID: 26407872 DOI: 10.1007/s11302-015-9471-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Accepted: 09/14/2015] [Indexed: 12/28/2022] Open
Abstract
This review describing the role of P2Y receptors in neuropathological conditions focuses on obvious differences between results demonstrating either a role in neuroprotection or in neurodegeneration, depending on in vitro and in vivo models. Such critical juxtaposition puts special emphasis on discussions of beneficial and detrimental effects of P2Y receptor agonists and antagonists in these models. The mechanisms reported to underlie the protection in vitro include increased expression of oxidoreductase genes, like carbonyl reductase and thioredoxin reductase; increased expression of inhibitor of apoptosis protein-2; extracellular signal-regulated kinase- and Akt-mediated antiapoptotic signaling; increased expression of Bcl-2 proteins, neurotrophins, neuropeptides, and growth factors; decreased Bax expression; non-amyloidogenic APP shedding; and increased neurite outgrowth in neuronal cells. Animal studies investigating the influence of P2Y receptors in middle cerebral artery occlusion (MCAO) models for stroke prove beneficial effects of P2Y receptor antagonists. In MCAO mice and rats, the application of broad-range P2 receptor antagonists decreased the infarct volume and improved neurological outcome. Moreover, antagonists of the P2Y1 receptor, one of the most abundant P2Y receptor subtypes in brain tissue, decreased neuronal loss and improved spatial memory in rats after traumatic brain injury (TBI). Currently available data show a discrepancy between in vitro and in vivo models concerning the benefits of P2Y receptor activation in pathological conditions. In vitro models demonstrate protection by P2Y receptor agonists, but in vivo P2Y receptor activation deteriorates the outcome after MCAO and controlled cortical impact brain injury, a TBI model. To broaden the scope of the review, we additionally discuss publications that demonstrate detrimental effects of P2Y receptor agonists in vitro and publications showing protective effects of agonists in vivo. All these studies help to better understand the significant role of P2Y receptors especially in stroke models and to develop pharmacological strategies for the treatment of stroke.
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Affiliation(s)
- Daniel Förster
- Otto-von-Guericke-Universität Magdeburg, Medizinische Fakultät, Institut für Neurobiochemie (Institut für Inflammation und Neurodegeneration), Leipziger Straße 44, 39120, Magdeburg, Germany
| | - Georg Reiser
- Otto-von-Guericke-Universität Magdeburg, Medizinische Fakultät, Institut für Neurobiochemie (Institut für Inflammation und Neurodegeneration), Leipziger Straße 44, 39120, Magdeburg, Germany.
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King BF. Purinergic signalling in the enteric nervous system (An overview of current perspectives). Auton Neurosci 2015; 191:141-7. [PMID: 26049261 DOI: 10.1016/j.autneu.2015.05.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Purinergic Signalling in the Enteric Nervous System involves the regulated release of ATP (or a structurally-related nucleotide) which activates an extensive suite of membrane-inserted receptors (P2X and P2Y subtypes) on a variety of cell types in the gastrointestinal tract. P2X receptors are gated ion-channels permeable to sodium, potassium and calcium. They depolarise cells, act as a pathway for calcium influx to activate calcium-dependent processes and initiate gene transcription, interact at a molecular level as a form of self-regulation with lipids within the cell wall (e.g. PIP2) and cross-react with other membrane-inserted receptors to regulate their activity (e.g. nAChRs). P2Y receptors are metabotropic receptors that couple to G-proteins. They may release calcium ions from intracellular stores to activate calcium-dependent processes, but also may activate calcium-independent signalling pathways and influence gene transcription. Originally ATP was a candidate only for NANC neurotransmission, for inhibitory motoneurons supplying the muscularis externa of the gastrointestinal tract and bringing about the fast IJP. Purinergic signalling later included neuron-neuron signalling in the ENS, via the production of either fast or slow EPSPs. Later still, purinergic signalling included the neuro-epithelial synapse-for efferent signalling to epithelia cells participating in secretion and absorption, and afferent signalling for chemoreception and mechanoreception at the surface of the mucosa. Many aspects of purinergic signalling have since been addressed in a series of highly-focussed and authoritative reviews. In this overview however, the current focus is on key aspects of purinergic signalling where there remains uncertainty and ambiguity, with the view to stimulating further research in these areas.
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Affiliation(s)
- Brian F King
- University College London (UCL), Department of Neuroscience, Physiology and Pharmacology (NPP), Royal Free Campus, Rowland Hill Street, Hampstead, London NW3 2PF, United Kingdom.
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Bartlett R, Stokes L, Sluyter R. The P2X7 receptor channel: recent developments and the use of P2X7 antagonists in models of disease. Pharmacol Rev 2015; 66:638-75. [PMID: 24928329 DOI: 10.1124/pr.113.008003] [Citation(s) in RCA: 313] [Impact Index Per Article: 34.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The P2X7 receptor is a trimeric ATP-gated cation channel found predominantly, but not exclusively, on immune cells. P2X7 activation results in a number of downstream events, including the release of proinflammatory mediators and cell death and proliferation. As such, P2X7 plays important roles in various inflammatory, immune, neurologic and musculoskeletal disorders. This review focuses on the use of P2X7 antagonists in rodent models of neurologic disease and injury, inflammation, and musculoskeletal and other disorders. The cloning and characterization of human, rat, mouse, guinea pig, dog, and Rhesus macaque P2X7, as well as recent observations regarding the gating and permeability of P2X7, are discussed. Furthermore, this review discusses polymorphic and splice variants of P2X7, as well as the generation and use of P2X7 knockout mice. Recent evidence for emerging signaling pathways downstream of P2X7 activation and the growing list of negative and positive modulators of P2X7 activation and expression are also described. In addition, the use of P2X7 antagonists in numerous rodent models of disease is extensively summarized. Finally, the use of P2X7 antagonists in clinical trials in humans and future directions exploring P2X7 as a therapeutic target are described.
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Affiliation(s)
- Rachael Bartlett
- School of Biological Sciences, University of Wollongong, New South Wales, Australia and Illawarra Health and Medical Research Institute, Wollongong, New South Wales, Australia (R.B., R.S.); and Health Innovations Research Institute, School of Medical Sciences, RMIT University, Bundoora, Victoria, Australia (L.S.)
| | - Leanne Stokes
- School of Biological Sciences, University of Wollongong, New South Wales, Australia and Illawarra Health and Medical Research Institute, Wollongong, New South Wales, Australia (R.B., R.S.); and Health Innovations Research Institute, School of Medical Sciences, RMIT University, Bundoora, Victoria, Australia (L.S.)
| | - Ronald Sluyter
- School of Biological Sciences, University of Wollongong, New South Wales, Australia and Illawarra Health and Medical Research Institute, Wollongong, New South Wales, Australia (R.B., R.S.); and Health Innovations Research Institute, School of Medical Sciences, RMIT University, Bundoora, Victoria, Australia (L.S.)
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11
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Jacobson KA, Balasubramanian R, Deflorian F, Gao ZG. G protein-coupled adenosine (P1) and P2Y receptors: ligand design and receptor interactions. Purinergic Signal 2012; 8:419-36. [PMID: 22371149 PMCID: PMC3360101 DOI: 10.1007/s11302-012-9294-7] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2011] [Accepted: 01/30/2012] [Indexed: 12/17/2022] Open
Abstract
The medicinal chemistry and pharmacology of the four subtypes of adenosine receptors (ARs) and the eight subtypes of P2Y receptors (P2YRs, activated by a range of purine and pyrimidine mono- and dinucleotides) has recently advanced significantly leading to selective ligands. X-ray crystallographic structures of both agonist- and antagonist-bound forms of the A(2A)AR have provided unprecedented three-dimensional detail concerning molecular recognition in the binding site and the conformational changes in receptor activation. It is apparent that this ubiquitous cell signaling system has implications for understanding and treating many diseases. ATP and other nucleotides are readily released from intracellular sources under conditions of injury and organ stress, such as hypoxia, ischemia, or mechanical stress, and through channels and vesicular release. Adenosine may be generated extracellularly or by cellular release. Therefore, depending on pathophysiological factors, in a given tissue, there is often a tonic activation of one or more of the ARs or P2YRs that can be modulated by exogenous agents for a beneficial effect. Thus, this field has provided fertile ground for pharmaceutical development, leading to clinical trials of selective receptor ligands as imaging agents or for conditions including cardiac arrhythmias, ischemia/reperfusion injury, diabetes, pain, thrombosis, Parkinson's disease, rheumatoid arthritis, psoriasis, dry eye disease, pulmonary diseases such as cystic fibrosis, glaucoma, cancer, chronic hepatitis C, and other diseases.
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Affiliation(s)
- Kenneth A Jacobson
- Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
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12
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The role of purinergic receptors in cancer-induced bone pain. J Osteoporos 2012; 2012:758181. [PMID: 23091774 PMCID: PMC3469246 DOI: 10.1155/2012/758181] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2012] [Accepted: 08/22/2012] [Indexed: 12/12/2022] Open
Abstract
Cancer-induced bone pain severely compromises the quality of life of many patients suffering from bone metastasis, as current therapies leave some patients with inadequate pain relief. The recent development of specific animal models has increased the understanding of the molecular and cellular mechanisms underlying cancer-induced bone pain including the involvement of ATP and the purinergic receptors in the progression of the pain state. In nociception, ATP acts as an extracellular messenger to transmit sensory information both at the peripheral site of tissue damage and in the spinal cord. Several of the purinergic receptors have been shown to be important for the development and maintenance of neuropathic and inflammatory pain, and studies have demonstrated the importance of both peripheral and central mechanisms. We here provide an overview of the current literature on the role of purinergic receptors in cancer-induced bone pain with emphasis on some of the difficulties related to studying this complex pain state.
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