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Minamihata T, Takano K, Moriyama M, Nakamura Y. Lysophosphatidylinositol, an Endogenous Ligand for G Protein-Coupled Receptor 55, Has Anti-inflammatory Effects in Cultured Microglia. Inflammation 2021; 43:1971-1987. [PMID: 32519268 DOI: 10.1007/s10753-020-01271-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Lysophosphatidylinositol (LysoPI), an endogenous ligand for G protein-coupled receptor (GPR) 55, has been known to show various functions in several tissues and cells; however, its roles in the central nervous system (CNS) are not well known. In particular, the detailed effects of LysoPI on microglial inflammatory responses remain unknown. Microglia is the immune cell that has important functions in maintaining immune homeostasis of the CNS. In this study, we explored the effects of LysoPI on inflammatory responses using the mouse microglial cell line BV-2, which was stimulated with lipopolysaccharide (LPS), and some results were confirmed also in rat primary microglia. LysoPI was found to reduce LPS-induced nitric oxide (NO) production and inducible NO synthase protein expression without affecting cell viability in BV-2 cells. LysoPI also suppressed intracellular generation of reactive oxygen species both in BV-2 cells and primary microglia and cytokine release in BV-2 cells. In addition, LysoPI treatment decreased phagocytic activity of LPS-stimulated BV-2 cells and primary microglia. The GPR55 antagonist CID16020046 completely inhibited LysoPI-induced downregulation of phagocytosis in BV-2 microglia, but did not affect the LysoPI-induced decrease in NO production. Our results suggest that LysoPI suppresses microglial phagocytosis via a GPR55-dependent pathway and NO production via a GPR55-independent pathway. LysoPI may contribute to neuroprotection in pathological conditions such as brain injury or neurodegenerative diseases, through its suppressive role in the microglial inflammatory response.
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Affiliation(s)
- Tomoki Minamihata
- Laboratory of Integrative Physiology in Veterinary Sciences, Osaka Prefecture University, 1-58 Rinku Ourai Kita, Izumisano, Osaka, 598-8531, Japan
| | - Katsura Takano
- Laboratory of Integrative Physiology in Veterinary Sciences, Osaka Prefecture University, 1-58 Rinku Ourai Kita, Izumisano, Osaka, 598-8531, Japan
| | - Mitsuaki Moriyama
- Laboratory of Integrative Physiology in Veterinary Sciences, Osaka Prefecture University, 1-58 Rinku Ourai Kita, Izumisano, Osaka, 598-8531, Japan.
| | - Yoichi Nakamura
- Laboratory of Integrative Physiology in Veterinary Sciences, Osaka Prefecture University, 1-58 Rinku Ourai Kita, Izumisano, Osaka, 598-8531, Japan
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Shon JC, Lee SM, Jung JH, Wu Z, Kwon YS, Sim HJ, Seo JS. Integrated metabolomics and lipidomics reveals high accumulation of polyunsaturated lysoglycerophospholipids in human lung fibroblasts exposed to fine particulate matter. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2020; 202:110896. [PMID: 32622306 DOI: 10.1016/j.ecoenv.2020.110896] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 06/10/2020] [Accepted: 06/12/2020] [Indexed: 06/11/2023]
Abstract
Exposure to fine particulate matter (PM) comprising toxic compounds arising from air pollution is a major human health concern. It is linked to increased mortality and incidence of various lung diseases. However, the mechanisms underlying the toxic effects of PM on lung fibroblasts have not been fully explored. We used targeted quantitative metabolomics and lipidomics analysis along with cytotoxicity studies to comprehensively characterize the alterations in the metabolite profiles of human lung fibroblasts (HEL 299) upon exposure to PM2.5 and PM10. This exposure at 50 μg/mL for 72 h induced an abnormally high apoptotic response via triggering intracellular reactive oxygen species (ROS) production and mitochondrial dysfunction through an imbalance between pro- and anti-apoptotic signaling pathways. The cytotoxic effects of PM2.5 were more severe than those of PM10. Metabolomics and lipidomics analyses revealed that PM exposure triggered substantial changes in the cellular metabolite profile, which involved reduced mitochondria-related metabolites such as tricarboxylic acid (TCA) cycle intermediates, amino acids, and free fatty acids as well as increased lysoglycerophospholipids (LPLs) containing polyunsaturated fatty acids. The decrease in mitochondria-related metabolites suggested that PM exposure led to reduced TCA cycle capacity and energy production. Apoptotic and inflammatory responses as well as mitochondrial dysfunction were likely to be accelerated because of excessive accumulation of LPLs, contributing to the disruption of membrane rafts and Ca2+ homeostasis and causing increased mitochondrial ROS formation. These results provide valuable insights regarding the toxic effects of PM exposure. Our study also provides a new direction for research on PM exposure-related health disorders using different cell lines.
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Affiliation(s)
- Jong Cheol Shon
- Environmental Chemistry Research Group, Korea Institute of Toxicology, Jinju, 52834, Republic of Korea
| | - Seon Min Lee
- Biological Resources Research Group, Korea Institute of Toxicology, Jinju, 52834, Republic of Korea
| | - Jung-Hoon Jung
- Environmental Chemistry Research Group, Korea Institute of Toxicology, Jinju, 52834, Republic of Korea
| | - Zhexue Wu
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Kyungpook National University, Daegu, 41566, Republic of Korea
| | - Young Sang Kwon
- Environmental Chemistry Research Group, Korea Institute of Toxicology, Jinju, 52834, Republic of Korea
| | - Hee-Jung Sim
- Environmental Chemistry Research Group, Korea Institute of Toxicology, Jinju, 52834, Republic of Korea
| | - Jong-Su Seo
- Environmental Chemistry Research Group, Korea Institute of Toxicology, Jinju, 52834, Republic of Korea.
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Briand-Mésange F, Pons V, Allart S, Masquelier J, Chicanne G, Beton N, Payrastre B, Muccioli GG, Ausseil J, Davignon JL, Salles JP, Chap H. Glycerophosphodiesterase 3 (GDE3) is a lysophosphatidylinositol-specific ectophospholipase C acting as an endocannabinoid signaling switch. J Biol Chem 2020; 295:15767-15781. [PMID: 32917725 DOI: 10.1074/jbc.ra120.015278] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 09/03/2020] [Indexed: 12/11/2022] Open
Abstract
Endocannabinoid signaling plays a regulatory role in various (neuro)biological functions. 2-arachidonoylglycerol (2-AG) is the most abundant endocannabinoid, and although its canonical biosynthetic pathway involving phosphoinositide-specific phospholipase C and diacylglycerol lipase α is known, alternative pathways remain unsettled. Here, we characterize a noncanonical pathway implicating glycerophosphodiesterase 3 (GDE3, from GDPD2 gene). Human GDE3 expressed in HEK293T cell membranes catalyzed the conversion of lysophosphatidylinositol (LPI) into monoacylglycerol and inositol-1-phosphate. The enzyme was equally active against 1-acyl and 2-acyl LPI. When using 2-acyl LPI, where arachidonic acid is the predominant fatty acid, LC-MS analysis identified 2-AG as the main product of LPI hydrolysis by GDE3. Furthermore, inositol-1-phosphate release into the medium occurred upon addition of LPI to intact cells, suggesting that GDE3 is actually an ecto-lysophospholipase C. In cells expressing G-protein-coupled receptor GPR55, GDE3 abolished 1-acyl LPI-induced signaling. In contrast, upon simultaneous ex-pression of GDE3 and cannabinoid receptor CB2, 2-acyl LPI evoked the same signal as that induced by 2-AG. These data strongly suggest that, in addition to degrading the GPR55 LPI ligand, GDE3 can act as a switch between GPR55 and CB2 signaling. Coincident with a major expression of both GDE3 and CB2 in the spleen, spleens from transgenic mice lacking GDE3 displayed doubling of LPI content compared with WT mice. Decreased production of 2-AG in whole spleen was also observed, supporting the in vivo relevance of our findings. These data thus open a new research avenue in the field of endocannabinoid generation and reinforce the view of GPR55 and LPI being genuine actors of the endocannabinoid system.
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Affiliation(s)
- Fabienne Briand-Mésange
- Center for Physiopathology of Toulouse Purpan, University of Toulouse, Toulouse, France; National Center for Scientific Research, Toulouse, France; National Institute of Health and Medical Research, Paul Sabatier University, Toulouse, France
| | - Véronique Pons
- Institute of Metabolic and Cardiovascular Diseases, Toulouse, France; National Institute of Health and Medical Research, Paul Sabatier University, Toulouse, France
| | - Sophie Allart
- Center for Physiopathology of Toulouse Purpan, University of Toulouse, Toulouse, France; National Center for Scientific Research, Toulouse, France; National Institute of Health and Medical Research, Paul Sabatier University, Toulouse, France
| | - Julien Masquelier
- Bioanalysis and Pharmacology of Bioactive Lipids Research Group, Louvain Drug Research Institute, Catholic University of Louvain, Brussels, Belgium
| | - Gaëtan Chicanne
- Institute of Metabolic and Cardiovascular Diseases, Toulouse, France; National Institute of Health and Medical Research, Paul Sabatier University, Toulouse, France
| | - Nicolas Beton
- Center for Physiopathology of Toulouse Purpan, University of Toulouse, Toulouse, France; National Center for Scientific Research, Toulouse, France; National Institute of Health and Medical Research, Paul Sabatier University, Toulouse, France
| | - Bernard Payrastre
- Institute of Metabolic and Cardiovascular Diseases, Toulouse, France; National Institute of Health and Medical Research, Paul Sabatier University, Toulouse, France
| | - Giulio G Muccioli
- Bioanalysis and Pharmacology of Bioactive Lipids Research Group, Louvain Drug Research Institute, Catholic University of Louvain, Brussels, Belgium
| | - Jérôme Ausseil
- Center for Physiopathology of Toulouse Purpan, University of Toulouse, Toulouse, France; National Center for Scientific Research, Toulouse, France; National Institute of Health and Medical Research, Paul Sabatier University, Toulouse, France
| | - Jean-Luc Davignon
- Center for Physiopathology of Toulouse Purpan, University of Toulouse, Toulouse, France; National Center for Scientific Research, Toulouse, France; National Institute of Health and Medical Research, Paul Sabatier University, Toulouse, France
| | - Jean-Pierre Salles
- Center for Physiopathology of Toulouse Purpan, University of Toulouse, Toulouse, France; National Center for Scientific Research, Toulouse, France; National Institute of Health and Medical Research, Paul Sabatier University, Toulouse, France
| | - Hugues Chap
- Center for Physiopathology of Toulouse Purpan, University of Toulouse, Toulouse, France; National Center for Scientific Research, Toulouse, France; National Institute of Health and Medical Research, Paul Sabatier University, Toulouse, France.
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GPR55-mediated effects on brain microvascular endothelial cells and the blood-brain barrier. Neuroscience 2019; 414:88-98. [PMID: 31279825 DOI: 10.1016/j.neuroscience.2019.06.039] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Revised: 06/26/2019] [Accepted: 06/27/2019] [Indexed: 12/31/2022]
Abstract
GPR55, an atypical cannabinoid receptor activated by lysophosphatidylinositol (LPI) has been involved in various physiological and pathological processes. We examined the effect of GPR55 activation on rat brain microvascular endothelial cells (RBMVEC), an essential component of the blood-brain barrier (BBB). GPR55 was detected in RBMVEC by western blot and immunocytochemistry. Treatment of RBMVEC with LPI increased cytosolic Ca2+ concentration, [Ca2+]i, in a concentration-dependent manner; the effect was abolished by the GPR55 antagonist, ML-193. Repetitive application of LPI induced tachyphylaxis. LPI-induced increase in [Ca2+]i was not sensitive to U-73122, a phospholipase C inhibitor, but was abolished by the blockade of voltage-gated Ca2+ channels or in Ca2+-free saline, indicating that Ca2+ influx was involved in this response. LPI induced a biphasic change in RBMVEC membrane potential: a fast depolarization followed by a long-lasting hyperpolarization. The hyperpolarization phase was prevented by apamin and charibdotoxin, inhibitors of small- and intermediate-conductance Ca2+-activated K+ channels (KCa). Immunofluorescence studies indicate that LPI produced transient changes in tight and adherens junctions proteins and F-actin stress fibers. LPI decreased the electrical resistance of RBMVEC monolayer assessed with Electric Cell-Substrate Impedance Sensing (ECIS) in a dose-dependent manner. In vivo studies indicate that systemic administration of LPI increased the permeability of the BBB, assessed with Evans Blue method. Taken together, our results indicate that GPR55 activation modulates the function of endothelial cells of brain microvessels, produces a transient reduction in endothelial barrier function and increases BBB permeability.
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Guerrero-Alba R, Barragán-Iglesias P, González-Hernández A, Valdez-Moráles EE, Granados-Soto V, Condés-Lara M, Rodríguez MG, Marichal-Cancino BA. Some Prospective Alternatives for Treating Pain: The Endocannabinoid System and Its Putative Receptors GPR18 and GPR55. Front Pharmacol 2019; 9:1496. [PMID: 30670965 PMCID: PMC6331465 DOI: 10.3389/fphar.2018.01496] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Accepted: 12/07/2018] [Indexed: 12/12/2022] Open
Abstract
Background: Marijuana extracts (cannabinoids) have been used for several millennia for pain treatment. Regarding the site of action, cannabinoids are highly promiscuous molecules, but only two cannabinoid receptors (CB1 and CB2) have been deeply studied and classified. Thus, therapeutic actions, side effects and pharmacological targets for cannabinoids have been explained based on the pharmacology of cannabinoid CB1/CB2 receptors. However, the accumulation of confusing and sometimes contradictory results suggests the existence of other cannabinoid receptors. Different orphan proteins (e.g., GPR18, GPR55, GPR119, etc.) have been proposed as putative cannabinoid receptors. According to their expression, GPR18 and GPR55 could be involved in sensory transmission and pain integration. Methods: This article reviews select relevant information about the potential role of GPR18 and GPR55 in the pathophysiology of pain. Results: This work summarized novel data supporting that, besides cannabinoid CB1 and CB2 receptors, GPR18 and GPR55 may be useful for pain treatment. Conclusion: There is evidence to support an antinociceptive role for GPR18 and GPR55.
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Affiliation(s)
- Raquel Guerrero-Alba
- Departamento de Fisiología y Farmacología, Centro de Ciencias Básicas, Universidad Autónoma de Aguascalientes, Aguascalientes, Mexico
| | - Paulino Barragán-Iglesias
- School of Behavioral and Brain Sciences and Center for Advanced Pain Studies, University of Texas at Dallas, Richardson, TX, United States
| | - Abimael González-Hernández
- Departamento de Neurobiología del Desarrollo y Neurofisiología, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Santiago de Querétaro, Mexico
| | - Eduardo E Valdez-Moráles
- Cátedras CONACYT, Departamento de Cirugía, Centro de Ciencias Biomédicas, Universidad Autónoma de Aguascalientes, Aguascalientes, Mexico
| | - Vinicio Granados-Soto
- Neurobiology of Pain Laboratory, Departamento de Farmacobiología, Cinvestav, Mexico City, Mexico
| | - Miguel Condés-Lara
- Departamento de Neurobiología del Desarrollo y Neurofisiología, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Santiago de Querétaro, Mexico
| | - Martín G Rodríguez
- Departamento de Fisiología y Farmacología, Centro de Ciencias Básicas, Universidad Autónoma de Aguascalientes, Aguascalientes, Mexico
| | - Bruno A Marichal-Cancino
- Departamento de Fisiología y Farmacología, Centro de Ciencias Básicas, Universidad Autónoma de Aguascalientes, Aguascalientes, Mexico
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Abstract
Cannabinoids influence cardiovascular variables in health and disease via multiple mechanisms. The chapter covers the impact of cannabinoids on cardiovascular function in physiology and pathology and presents a critical analysis of the proposed signalling pathways governing regulation of cardiovascular function by endogenously produced and exogenous cannabinoids. We know that endocannabinoid system is overactivated under pathological conditions and plays both a protective compensatory role, such as in some forms of hypertension, atherosclerosis and other inflammatory conditions, and a pathophysiological role, such as in disease states associated with excessive hypotension. This chapter focuses on the mechanisms affecting hemodynamics and vasomotor effects of cannabinoids in health and disease states, highlighting mismatches between some studies. The chapter will first review the effects of marijuana smoking on cardiovascular system and then describe the impact of exogenous cannabinoids on cardiovascular parameters in humans and experimental animals. This will be followed by analysis of the impact of cannabinoids on reactivity of isolated vessels. The article critically reviews current knowledge on cannabinoid induction of vascular relaxation by cannabinoid receptor-dependent and -independent mechanisms and dysregulation of vascular endocannabinoid signaling in disease states.
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Affiliation(s)
- Alexander I Bondarenko
- Circulatory Physiology Department, Bogomoletz Institute of Physiology National Academy of Sciences of Ukraine, Kiev, Ukraine.
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7
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Brautigan DL, Li R, Kubicka E, Turner SD, Garcia JS, Weintraut ML, Wong EA. Lysolecithin as feed additive enhances collagen expression and villus length in the jejunum of broiler chickens. Poult Sci 2018; 96:2889-2898. [PMID: 28444343 DOI: 10.3382/ps/pex078] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Accepted: 03/18/2017] [Indexed: 12/15/2022] Open
Abstract
Adding lysolecithin to feed has reportedly improved the performance of broiler chickens. Lysolecithin is generated by phospholipase catalyzed hydrolysis of lecithin. The enzymatic reaction converts various phospholipids into the corresponding lysophospholipids, with lysophosphatidylcholine (LPC) one of the primary products. Here we compared supplementation with a commercial lysolecithin (Lysoforte®) with comparable levels of highly purified LPC for effects on broilers. Despite no differences in weight gain during the starter period, we discovered a significant increase in average villus length with lysolecithin and an increase in villus width with purified LPC. High-throughput gene expression microarray analyses revealed many more genes were regulated in the epithelium of the jejunum by lysolecithin compared to purified LPC. The most up-regulated genes and pathways were for collagen, extracellular matrix, and integrins. Staining sections of the jejunum with Picrosirius Red confirmed the increased deposition of collagen fibrils in the villi of broilers fed lysolecithin, but not purified LPC. Thus, lysolecithin elicits gene expression in the intestinal epithelium, leading to enhanced collagen deposition and villus length. Purified LPC alone as a supplement does not mimic these responses. Feed supplementation with lysolecithin triggers changes in the intestinal epithelium with the potential to improve overall gut health and performance.
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Affiliation(s)
- D L Brautigan
- Center for Cell Signaling and Department of Microbiology, Immunology & Cancer Biology, University of Virginia School of Medicine, Charlottesville 22908
| | - R Li
- Center for Cell Signaling and Department of Microbiology, Immunology & Cancer Biology, University of Virginia School of Medicine, Charlottesville 22908
| | - E Kubicka
- Center for Cell Signaling and Department of Microbiology, Immunology & Cancer Biology, University of Virginia School of Medicine, Charlottesville 22908
| | - S D Turner
- Department of Public Health Sciences, University of Virginia School of Medicine, Charlottesville 22908
| | - J S Garcia
- Department of Animal and Poultry Sciences, Virginia Tech, Blacksburg 24061
| | - M L Weintraut
- Department of Animal and Poultry Sciences, Virginia Tech, Blacksburg 24061
| | - E A Wong
- Department of Animal and Poultry Sciences, Virginia Tech, Blacksburg 24061
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Alhouayek M, Masquelier J, Muccioli GG. Lysophosphatidylinositols, from Cell Membrane Constituents to GPR55 Ligands. Trends Pharmacol Sci 2018; 39:586-604. [PMID: 29588059 DOI: 10.1016/j.tips.2018.02.011] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Revised: 02/20/2018] [Accepted: 02/28/2018] [Indexed: 12/25/2022]
Abstract
Lysophosphatidylinositols (LPIs) are membrane constituents that alter the properties of said membranes. However, recent data showing that the once orphan receptor, GPR55, can act as a receptor for LPIs has sparked a renewed interest in LPIs as bioactive lipids. As evidence supporting the importance of LPIs and/or GPR55 is continuously accumulating and because LPI levels are altered in a number of pathologies such as obesity and cancer, the coming years should bring new, exciting discoveries to this field. In this review, we discuss the recent work on LPIs and on their molecular target, the GPR55 receptor. First, we summarize the metabolism of LPIs before outlining the cellular pathways activated by GPR55. Then, we review the actions of LPIs and GPR55 that could have potential pharmacological or therapeutic applications in several pathophysiological settings, such as cancer, obesity, pain, and inflammation.
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Affiliation(s)
- Mireille Alhouayek
- Bioanalysis and Pharmacology of Bioactive Lipids Research Group, Louvain Drug Research Institute, Université catholique de Louvain, 1200 Bruxelles, Belgium; These authors contributed equally to this work
| | - Julien Masquelier
- Bioanalysis and Pharmacology of Bioactive Lipids Research Group, Louvain Drug Research Institute, Université catholique de Louvain, 1200 Bruxelles, Belgium; These authors contributed equally to this work
| | - Giulio G Muccioli
- Bioanalysis and Pharmacology of Bioactive Lipids Research Group, Louvain Drug Research Institute, Université catholique de Louvain, 1200 Bruxelles, Belgium.
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Bondarenko AI, Panasiuk O, Drachuk K, Montecucco F, Brandt KJ, Mach F. The quest for endothelial atypical cannabinoid receptor: BK Ca channels act as cellular sensors for cannabinoids in in vitro and in situ endothelial cells. Vascul Pharmacol 2018; 102:44-55. [PMID: 29355732 PMCID: PMC6481560 DOI: 10.1016/j.vph.2018.01.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Revised: 01/10/2018] [Accepted: 01/16/2018] [Indexed: 12/20/2022]
Abstract
Endothelium-dependent component of cannabinoid-induced vasodilation has been postulated to require G-protein-coupled non-CB1/CB2 endothelial cannabinoid (eCB) receptor. GPR18 was proposed as a candidate for eCBR. To address the hypothesis that the effects attributed to eCBR are mediated by G-protein-coupled receptor (GPCR)-independent targets, we studied the electrical responses in endothelial cells, focusing on BKCa channels. In patches excised from endothelial-derived EA.hy926 cells, N-arachidonoyl glycine (NAGly) and abnormal cannabidiol (abn-cbd), prototypical agonists for eCB receptor, stimulate single BKCa activity in a concentration- and Ca2+-dependent manner. The postulated eCB receptor inhibitors rimonabant and AM251 were found to inhibit basal and stimulated by NAGly- and abn-cbd BKCa activity in cell-free patches. In isolated mice aortas, abn-cbd and NAGly produced endothelial cell hyperpolarization that was sensitive to paxilline, a selective BKCa inhibitor, but not to GPR18 antibody, and mimicked by NS1619, a direct BKCa opener. In excised patches from mice aortic endothelium, single channel activity with characteristics similar to BKCa was established by the addition of abn-cbd and NAGly. We conclude that the two cannabinoids abn-cbd and NAGly initiate a GPR18-independent activation of BKCa channels in mice aortic endothelial cells that might contribute to vasodilation to cannabinoids.
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Affiliation(s)
- Alexander I Bondarenko
- Circulatory Physiology Department, Bogomoletz Institute of Physiology NAS of Ukraine, Bogomoletz Str 4, Kiev 01024, Ukraine; Institute of Molecular Biology and Biochemistry, Medical University of Graz, Harrachgasse 21/III, Graz, 8010, Austria.
| | - Olga Panasiuk
- Circulatory Physiology Department, Bogomoletz Institute of Physiology NAS of Ukraine, Bogomoletz Str 4, Kiev 01024, Ukraine
| | - Konstantin Drachuk
- Circulatory Physiology Department, Bogomoletz Institute of Physiology NAS of Ukraine, Bogomoletz Str 4, Kiev 01024, Ukraine
| | - Fabrizio Montecucco
- First Clinic of Internal Medicine, Department of Internal Medicine, University of Genoa, 6 viale Benedetto XV, 16132 Genoa, Italy; Ospedale Policlinico San Martino, largo Benzi 10, 16132 Genoa, Italy; Centre of Excellence for Biomedical Research (CEBR), University of Genoa, 9 viale Benedetto XV, 16132 Genoa, Italy
| | - Karim J Brandt
- Division of Cardiology, Foundation for Medical Researches, Department of Internal Medicine, University of Geneva, Av. de la Roseraie 64, CH 1211, Geneva 4, Switzerland
| | - François Mach
- Division of Cardiology, Foundation for Medical Researches, Department of Internal Medicine, University of Geneva, Av. de la Roseraie 64, CH 1211, Geneva 4, Switzerland
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10
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Karpińska O, Baranowska-Kuczko M, Malinowska B, Kloza M, Kusaczuk M, Gęgotek A, Golec P, Kasacka I, Kozłowska H. Mechanisms of l-alpha-lysophosphatidylinositol-induced relaxation in human pulmonary arteries. Life Sci 2017; 192:38-45. [PMID: 29155298 DOI: 10.1016/j.lfs.2017.11.020] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Revised: 11/11/2017] [Accepted: 11/15/2017] [Indexed: 01/13/2023]
Abstract
AIMS l-Alpha-lysophosphatidylinositol (LPI) is an endogenous agonist of G protein-coupled receptor 55 (GPR55) which relaxes mesenteric arteries on activation. The aim of the present study was to determine the influence and underlying mechanisms of LPI-induced relaxation in human pulmonary arteries (hPAs). MAIN METHODS Functional studies were performed in isolated hPAs using organ bath technique. The expression of GPR55 in hPAs and bronchioles was determined by real-time qPCR, Western blot analysis, and immunohistochemistry. KEY FINDINGS LPI induced a concentration-dependent vasorelaxation in endothelium-intact hPAs. This effect was attenuated by the GPR55 antagonist CID16020046, the peroxisome proliferator-activated receptor-γ (PPARγ) antagonist GW9662, the putative endothelial cannabinoid receptor (CBe) antagonist O-1918 and the inhibitor of nitric oxide (NO) synthase (L-NAME). In addition, vasorelaxation was also attenuated by the presence of a high KCl concentration, selective blockers of small (KCa2.3; UCL1684), intermediate (KCa3.1; TRAM-34) and large conductance (KCa1.1; iberiotoxin) calcium-activated potassium channels and by endothelium denudation. However, vasorelaxation was not attenuated by the cannabinoid CB1 receptor antagonist AM251 or by the cyclooxygenase inhibitor indomethacin. SIGNIFICANCE The study showed that the LPI-induced vasorelaxation was endothelium-dependent and mediated by GPR55, PPARγ and CBe receptors, occurred in a NO- and calcium-activated potassium channel-dependent manner in isolated hPAs. LPI seems to possess positive, hypotensive properties in pulmonary vascular bed.
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Affiliation(s)
- Olga Karpińska
- Department of Experimental Physiology and Pathophysiology, Medical University of Białystok, Mickiewicza Str. 2A, 15-089 Białystok, Poland.
| | - Marta Baranowska-Kuczko
- Department of Experimental Physiology and Pathophysiology, Medical University of Białystok, Mickiewicza Str. 2A, 15-089 Białystok, Poland
| | - Barbara Malinowska
- Department of Experimental Physiology and Pathophysiology, Medical University of Białystok, Mickiewicza Str. 2A, 15-089 Białystok, Poland
| | - Monika Kloza
- Department of Experimental Physiology and Pathophysiology, Medical University of Białystok, Mickiewicza Str. 2A, 15-089 Białystok, Poland
| | - Magdalena Kusaczuk
- Department of Pharmaceutical Biochemistry, Medical University of Białystok, Mickiewicza Str. 2A, 15-089 Białystok, Poland
| | - Agnieszka Gęgotek
- Department of Inorganic and Analytical Chemistry, Medical University of Białystok, Mickiewicza Str. 2D, 15-222 Białystok, Poland
| | - Paweł Golec
- Department of Thoracic Surgery, Medical University of Białystok, M. Skłodowskiej-Curie Str. 24A, 15-276 Białystok, Poland
| | - Irena Kasacka
- Department of Histology and Cytophysiology, Medical University of Białystok, Mickiewicza Str. 2C, 15-222 Białystok, Poland
| | - Hanna Kozłowska
- Department of Experimental Physiology and Pathophysiology, Medical University of Białystok, Mickiewicza Str. 2A, 15-089 Białystok, Poland
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Harada K, Kitaguchi T, Kamiya T, Aung KH, Nakamura K, Ohta K, Tsuboi T. Lysophosphatidylinositol-induced activation of the cation channel TRPV2 triggers glucagon-like peptide-1 secretion in enteroendocrine L cells. J Biol Chem 2017; 292:10855-10864. [PMID: 28533434 DOI: 10.1074/jbc.m117.788653] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Revised: 05/17/2017] [Indexed: 01/07/2023] Open
Abstract
The lysophosphatidylinositol (LPI) has crucial roles in multiple physiological processes, including insulin exocytosis from pancreatic islets. However, the role of LPI in secretion of glucagon-like peptide-1 (GLP-1), a hormone that enhances glucose-induced insulin secretion, is unclear. Here, we used the murine enteroendocrine L cell line GLUTag and primary murine small intestinal cells to elucidate the mechanism of LPI-induced GLP-1 secretion. Exogenous LPI addition increased intracellular Ca2+ concentrations ([Ca2+] i ) in GLUTag cells and induced GLP-1 secretion from both GLUTag and acutely prepared primary intestinal cells. The [Ca2+] i increase was suppressed by an antagonist for G protein-coupled receptor 55 (GPR55) and by silencing of GPR55 expression, indicating involvement of Gq and G12/13 signaling pathways in the LPI-induced increased [Ca2+] i levels and GLP-1 secretion. However, GPR55 agonists did not mimic many of the effects of LPI. We also found that phospholipase C inhibitor and Rho-associated kinase inhibitor suppressed the [Ca2+] i increase and that LPI increased the number of focal adhesions, indicating actin reorganization. Of note, blockage or silencing of transient receptor potential cation channel subfamily V member 2 (TRPV2) channels suppressed both the LPI-induced [Ca2+] i increase and GLP-1 secretion. Furthermore, LPI accelerated TRPV2 translocation to the plasma membrane, which was significantly suppressed by a GPR55 antagonist. These findings suggest that TRPV2 activation via actin reorganization induced by Gq and G12/13 signaling is involved in LPI-stimulated GLP-1 secretion in enteroendocrine L cells. Because GPR55 agonists largely failed to mimic the effects of LPI, its actions on L cells are at least partially independent of GPR55 activation.
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Affiliation(s)
- Kazuki Harada
- From the Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo 153-8902, Japan
| | - Tetsuya Kitaguchi
- Cell Signaling Group, Waseda Bioscience Research Institute in Singapore (WABIOS), Singapore 138667, Singapore.,Comprehensive Research Organization, Waseda University, Tokyo 162-0041, Japan, and
| | - Taichi Kamiya
- From the Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo 153-8902, Japan
| | - Kyaw Htet Aung
- National Research Institute for Child Health and Development, Tokyo 157-8535, Japan
| | - Kazuaki Nakamura
- National Research Institute for Child Health and Development, Tokyo 157-8535, Japan
| | - Kunihiro Ohta
- From the Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo 153-8902, Japan
| | - Takashi Tsuboi
- From the Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo 153-8902, Japan,
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12
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Direct activation of Ca 2+ and voltage-gated potassium channels of large conductance by anandamide in endothelial cells does not support the presence of endothelial atypical cannabinoid receptor. Eur J Pharmacol 2017; 805:14-24. [PMID: 28327344 DOI: 10.1016/j.ejphar.2017.03.038] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 03/15/2017] [Accepted: 03/17/2017] [Indexed: 11/23/2022]
Abstract
Endocannabinoid anandamide induces endothelium-dependent relaxation commonly attributed to stimulation of the G-protein coupled endothelial anandamide receptor. The study addressed the receptor-independent effect of anandamide on large conductance Ca2+-dependent K+ channels expressed in endothelial cell line EA.hy926. Under resting conditions, 10µM anandamide did not significantly influence the resting membrane potential. In a Ca2+-free solution the cells were depolarized by ~10mV. Further administration of 10µM anandamide hyperpolarized the cells by ~8mV. In voltage-clamp mode, anandamide elicited the outwardly rectifying whole-cell current sensitive to paxilline but insensitive to GDPβS, a G-protein inhibitor. Administration of 70µM Mn2+, an agent used to promote integrin clustering, reversibly stimulated whole-cell current, but failed to further facilitate the anandamide-stimulated current. In an inside-out configuration, anandamide (0.1-30µM) facilitated single BKCa channel activity in a concentration-dependent manner within a physiological Ca2+ range and a wide range of voltages, mainly by reducing mean closed time. The effect is essentially eliminated following chelation of Ca2+ from the cytosolic face and pre-exposure to cholesterol-reducing agent methyl-β-cyclodextrin. O-1918 (3µM), a cannabidiol analog used as a selective antagonist of endothelial anandamide receptor, reduced BKCa channel activity in inside-out patches. These results do not support the existence of endothelial cannabinoid receptor and indicate that anandamide acts as a direct BKCa opener. The action does not require cell integrity or integrins and is caused by direct modification of BKCa channel activity.
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13
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Bondarenko AI, Montecucco F, Panasiuk O, Sagach V, Sidoryak N, Brandt KJ, Mach F. GPR55 agonist lysophosphatidylinositol and lysophosphatidylcholine inhibit endothelial cell hyperpolarization via GPR-independent suppression of Na +-Ca 2+ exchanger and endoplasmic reticulum Ca 2+ refilling. Vascul Pharmacol 2017; 89:39-48. [PMID: 28064014 DOI: 10.1016/j.vph.2017.01.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Revised: 12/21/2016] [Accepted: 01/03/2017] [Indexed: 11/18/2022]
Abstract
Lysophosphatidylinositol (LPI) and lysophosphatidylcholine (LPC) are lipid signaling molecules that induce endothelium-dependent vasodilation. In addition, LPC suppresses acetylcholine (Ach)-induced responses. We aimed to determine the influence of LPC and LPI on hyperpolarizing responses in vitro and in situ endothelial cells (EC) and identify the underlying mechanisms. Using patch-clamp method, we show that LPI and LPC inhibit EC hyperpolarization to histamine and suppress Na+/Ca2+ exchanged (NCX) currents in a concentration-dependent manner. The inhibition is non-mode-specific and unaffected by intracellular GDPβS infusion and tempol, a superoxide dismutase mimetic. In excised mouse aorta, LPI strongly inhibits the sustained and the peak endothelial hyperpolarization induced by Ach, but not by SKA-31, an opener of Ca2+-dependent K+ channels of intermediate and small conductance. The hyperpolarizing responses to consecutive histamine applications are strongly reduced by NCX inhibition. In a Ca2+-re-addition protocol, bepridil, a NCX inhibitor, and KB-R7943, a blocker of reversed NCX, inhibit the hyperpolarizing responses to Ca2+-re-addition following Ca2+ stores depletion. These finding indicate that LPC and LPI inhibit endothelial hyperpolarization to Ach and histamine independently of G-protein coupled receptors and superoxide anions. Reversed NCX is critical for ER Ca2+ refilling in EC. The inhibition of NCX by LPI and LPC underlies diminished endothelium-dependent responses and endothelial dysfunction accompanied by increased levels of these lipids in the blood.
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Affiliation(s)
- Alexander I Bondarenko
- Circulatory Physiology Department, Bogomoletz Institute of Physiology NAS of Ukraine, Bogomoletz Str.4, 01024 Kiev, Ukraine; Medical University of Graz, Institute of Molecular Biology and Biochemistry, Graz 8010, Austria.
| | - Fabrizio Montecucco
- First Clinic of Internal Medicine, Department of Internal Medicine, University of Genoa, 6 viale Benedetto XV, 16132 Genoa, Italy; IRCCS AOU San Martino - IST Istituto Nazionale per la Ricerca sul Cancro, Largo Benzi 10, 16132 Genoa, Italy
| | - Olga Panasiuk
- Circulatory Physiology Department, Bogomoletz Institute of Physiology NAS of Ukraine, Bogomoletz Str.4, 01024 Kiev, Ukraine
| | - Vadim Sagach
- Circulatory Physiology Department, Bogomoletz Institute of Physiology NAS of Ukraine, Bogomoletz Str.4, 01024 Kiev, Ukraine
| | - Nataliya Sidoryak
- Department of Physiology of Human and Animals, Melitopol State Pedagogical University, Ukraine
| | - Karim J Brandt
- Division of Cardiology, Foundation for Medical Researches, Department of Internal Medicine, University of Geneva, Av. de la Roseraie 64, CH-1211 Geneva 4, Switzerland
| | - François Mach
- Division of Cardiology, Foundation for Medical Researches, Department of Internal Medicine, University of Geneva, Av. de la Roseraie 64, CH-1211 Geneva 4, Switzerland
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14
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Liu B, Song S, Ruz-Maldonado I, Pingitore A, Huang GC, Baker D, Jones PM, Persaud SJ. GPR55-dependent stimulation of insulin secretion from isolated mouse and human islets of Langerhans. Diabetes Obes Metab 2016; 18:1263-1273. [PMID: 27561953 DOI: 10.1111/dom.12780] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2016] [Revised: 08/10/2016] [Accepted: 08/22/2016] [Indexed: 01/15/2023]
Abstract
AIMS The novel cannabinoid receptor GPR55 is expressed by rodent islets and it has been implicated in β-cell function in response to a range of ligands. This study evaluated the effects of GPR55 ligands on intracellular calcium ([Ca2+ ]i ) levels and insulin secretion from islets isolated from GPR55 knockout (GPR55 -/- ) mice, age-matched wildtype (WT) mice and human pancreas. MATERIALS AND METHODS GPR55 expression was determined by Western blotting and fluorescent immunohistochemistry. Changes in [Ca2+ ]i were measured by Fura-2 microfluorimetry. Dynamic insulin secretion was quantified by radioimmunoassay following perifusion of isolated islets. RhoA activity was monitored using a Rho binding domain pull down assay. RESULTS Western blotting indicated that MIN6 β-cells, mouse and human islets express GPR55 and its localization on human β-cells was demonstrated by fluorescent immunohistochemistry. The pharmacological GPR55 agonist O-1602 (10 μM) significantly stimulated [Ca2+ ]i and insulin secretion from WT mouse islets and these stimulatory effects were abolished in islets isolated from GPR55 -/- mice. In contrast, while the putative endogenous GPR55 agonist lysophosphatidylinositol (LPI, 5 µM) and the GPR55 antagonist cannabidiol (CBD, 1 µM) also elevated [Ca2+ ]i and insulin secretion, these effects were sustained in islets from GPR55 -/- mice. Stimulatory effects of O-1602 on [Ca2+ ]i and insulin secretion were also observed in experiments using human islets, but O-1602 did not activate RhoA in MIN6 β-cells. CONCLUSIONS Our results therefore suggest that GPR55 plays an important role in the regulation of mouse and human islet physiology, but LPI and CBD exert stimulatory effects on islet function by a GPR55-independent pathway(s).
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Affiliation(s)
- Bo Liu
- Division of Diabetes and Nutritional Sciences, Diabetes Research Group, King's College London, London, UK
| | - Shuang Song
- Division of Diabetes and Nutritional Sciences, Diabetes Research Group, King's College London, London, UK
| | - Inmaculada Ruz-Maldonado
- Division of Diabetes and Nutritional Sciences, Diabetes Research Group, King's College London, London, UK
| | - Attilio Pingitore
- Division of Diabetes and Nutritional Sciences, Diabetes Research Group, King's College London, London, UK
| | - Guo C Huang
- Division of Diabetes and Nutritional Sciences, Diabetes Research Group, King's College London, London, UK
| | - David Baker
- Centre for Neuroscience and Trauma, Barts and The London School of Medicine and Dentistry, London, UK
| | - Peter M Jones
- Division of Diabetes and Nutritional Sciences, Diabetes Research Group, King's College London, London, UK
| | - Shanta J Persaud
- Division of Diabetes and Nutritional Sciences, Diabetes Research Group, King's College London, London, UK
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15
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Ailte I, Lingelem ABD, Kavaliauskiene S, Bergan J, Kvalvaag AS, Myrann AG, Skotland T, Sandvig K. Addition of lysophospholipids with large head groups to cells inhibits Shiga toxin binding. Sci Rep 2016; 6:30336. [PMID: 27458147 PMCID: PMC4960542 DOI: 10.1038/srep30336] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Accepted: 06/30/2016] [Indexed: 12/20/2022] Open
Abstract
Shiga toxin (Stx), an AB5 toxin, binds specifically to the neutral glycosphingolipid Gb3 at the cell surface before being transported into cells. We here demonstrate that addition of conical lysophospholipids (LPLs) with large head groups inhibit Stx binding to cells whereas LPLs with small head groups do not. Lysophosphatidylinositol (LPI 18:0), the most efficient LPL with the largest head group, was selected for in-depth investigations to study how the binding of Stx is regulated. We show that the inhibition of Stx binding by LPI is reversible and possibly regulated by cholesterol since addition of methyl-β-cyclodextrin (mβCD) reversed the ability of LPI to inhibit binding. LPI-induced inhibition of Stx binding is independent of signalling and membrane turnover as it occurs in fixed cells as well as after depletion of cellular ATP. Furthermore, data obtained with fluorescent membrane dyes suggest that LPI treatment has a direct effect on plasma membrane lipid packing with shift towards a liquid disordered phase in the outer leaflet, while lysophosphoethanolamine (LPE), which has a small head group, does not. In conclusion, our data show that cellular treatment with conical LPLs with large head groups changes intrinsic properties of the plasma membrane and modulates Stx binding to Gb3.
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Affiliation(s)
- Ieva Ailte
- Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, Oslo, Norway.,Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Montebello, Oslo, Norway.,Department of Biosciences, University of Oslo, Oslo, Norway
| | - Anne Berit Dyve Lingelem
- Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, Oslo, Norway.,Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Montebello, Oslo, Norway
| | - Simona Kavaliauskiene
- Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, Oslo, Norway.,Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Montebello, Oslo, Norway.,Department of Biosciences, University of Oslo, Oslo, Norway
| | - Jonas Bergan
- Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, Oslo, Norway.,Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Montebello, Oslo, Norway.,Department of Research and Innovation, Østfold Hospital, Sarpsborg, Norway
| | - Audun Sverre Kvalvaag
- Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, Oslo, Norway.,Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Montebello, Oslo, Norway
| | - Anne-Grethe Myrann
- Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, Oslo, Norway.,Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Montebello, Oslo, Norway
| | - Tore Skotland
- Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, Oslo, Norway.,Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Montebello, Oslo, Norway
| | - Kirsten Sandvig
- Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, Oslo, Norway.,Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Montebello, Oslo, Norway.,Department of Biosciences, University of Oslo, Oslo, Norway
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16
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AL SULEIMANI YM, HILEY CR. Characterization of Calcium Signals Provoked by Lysophosphatidylinositol in Human Microvascular Endothelial Cells. Physiol Res 2016; 65:53-62. [DOI: 10.33549/physiolres.932962] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
The lipid molecule, lysophosphatidylinositol (LPI), is hypothesised to form part of a novel lipid signalling system that involves the G protein-coupled receptor GPR55 and distinct intracellular signalling cascades in endothelial cells. This work aimed to study the possible mechanisms involved in LPI-evoked cytosolic Ca2+ mobilization in human brain microvascular endothelial cells. Changes in intracellular Ca2+ concentrations were measured using cell population Ca2+ assay. LPI evoked biphasic elevation of intracellular calcium concentration, a rapid phase and a sustained phase. The rapid phase was attenuated by the inhibitor of PLC (U 73122), inhibitor of IP3 receptors, 2-APB and the depletor of endoplasmic reticulum Ca2+ store, thapsigargin. The sustained phase, on the other hand, was enhanced by U 73122 and abolished by the RhoA kinase inhibitor, Y-27632. In conclusion, the Ca2+ signal evoked by LPI is characterised by a rapid phase of Ca2+ release from the endoplasmic reticulum, and requires activation of the PLC-IP3 signalling pathway. The sustained phase mainly depends on RhoA kinase activation. LPI acts as novel lipid signalling molecule in endothelial cells, and elevation of cytosolic Ca2+ triggered by it may present an important intracellular message required in gene expression and controlling of vascular tone.
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Affiliation(s)
- Y. M. AL SULEIMANI
- Department of Pharmacology and Clinical Pharmacy, College of Medicine and Health Sciences, Sultan Qaboos University, Sultanate of Oman
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17
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Lysophosphatidylinositol Signalling and Metabolic Diseases. Metabolites 2016; 6:metabo6010006. [PMID: 26784247 PMCID: PMC4812335 DOI: 10.3390/metabo6010006] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Revised: 01/07/2016] [Accepted: 01/11/2016] [Indexed: 11/28/2022] Open
Abstract
Metabolism is a chemical process used by cells to transform food-derived nutrients, such as proteins, carbohydrates and fats, into chemical and thermal energy. Whenever an alteration of this process occurs, the chemical balance within the cells is impaired and this can affect their growth and response to the environment, leading to the development of a metabolic disease. Metabolic syndrome, a cluster of several metabolic risk factors such as abdominal obesity, insulin resistance, high cholesterol and high blood pressure, and atherogenic dyslipidaemia, is increasingly common in modern society. Metabolic syndrome, as well as other diseases, such as diabetes, obesity, hyperlipidaemia and hypertension, are associated with abnormal lipid metabolism. Cellular lipids are the major component of cell membranes; they represent also a valuable source of energy and therefore play a crucial role for both cellular and physiological energy homeostasis. In this review, we will focus on the physiological and pathophysiological roles of the lysophospholipid mediator lysophosphatidylinositol (LPI) and its receptor G-protein coupled receptor 55 (GPR55) in metabolic diseases. LPI is a bioactive lipid generated by phospholipase A (PLA) family of lipases which is believed to play an important role in several diseases. Indeed LPI can affect various functions such as cell growth, differentiation and motility in a number of cell-types. Recently published data suggest that LPI plays an important role in different physiological and pathological contexts, including a role in metabolism and glucose homeostasis.
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18
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Hofmann NA, Yang J, Trauger SA, Nakayama H, Huang L, Strunk D, Moses MA, Klagsbrun M, Bischoff J, Graier WF. The GPR 55 agonist, L-α-lysophosphatidylinositol, mediates ovarian carcinoma cell-induced angiogenesis. Br J Pharmacol 2015; 172:4107-18. [PMID: 25989290 PMCID: PMC4543616 DOI: 10.1111/bph.13196] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Revised: 04/10/2015] [Accepted: 05/11/2015] [Indexed: 12/24/2022] Open
Abstract
Background and Purpose Highly vascularized ovarian carcinoma secretes the putative endocannabinoid and GPR55 agonist, L-α-lysophosphatidylinositol (LPI), into the circulation. We aimed to assess the involvement of this agonist and its receptor in ovarian cancer angiogenesis. Experimental Approach Secretion of LPI by three ovarian cancer cell lines (OVCAR-3, OVCAR-5 and COV-362) was tested by mass spectrometry. Involvement of cancer cell-derived LPI on angiogenesis was tested in the in vivo chicken chorioallantoic membrane (CAM) assay along with the assessment of the effect of LPI on proliferation, network formation, and migration of neonatal and adult human endothelial colony-forming cells (ECFCs). Engagement of GPR55 was verified by using its pharmacological inhibitor CID16020046 and diminution of GPR55 expression by four different target-specific siRNAs. To study underlying signal transduction, Western blot analysis was performed. Key Results Ovarian carcinoma cell-derived LPI stimulated angiogenesis in the CAM assay. Applied LPI stimulated proliferation, network formation, and migration of neonatal ECFCs in vitro and angiogenesis in the in vivo CAM. The pharmacological GPR55 inhibitor CID16020046 inhibited LPI-stimulated ECFC proliferation, network formation and migration in vitro as well as ovarian carcinoma cell- and LPI-induced angiogenesis in vivo. Four target-specific siRNAs against GPR55 prevented these effects of LPI on angiogenesis. These pro-angiogenic effects of LPI were transduced by GPR55-dependent phosphorylation of ERK1/2 and p38 kinase. Conclusions and Implications We conclude that inhibiting the pro-angiogenic LPI/GPR55 pathway appears a promising target against angiogenesis in ovarian carcinoma.
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Affiliation(s)
- Nicole A Hofmann
- Institute for Molecular Biology and Biochemistry, Medical University Graz, Graz, Austria.,Vascular Biology Program, Boston Children's Hospital, Boston, MA, USA.,Department of Surgery, Harvard Medical School, Boston, MA, USA
| | - Jiang Yang
- Vascular Biology Program, Boston Children's Hospital, Boston, MA, USA.,Department of Surgery, Harvard Medical School, Boston, MA, USA
| | - Sunia A Trauger
- FAS Small Molecule Mass Spectrometry Facility, Harvard University, Boston, MA, USA
| | - Hironao Nakayama
- Vascular Biology Program, Boston Children's Hospital, Boston, MA, USA.,Department of Surgery, Harvard Medical School, Boston, MA, USA
| | - Lan Huang
- Vascular Biology Program, Boston Children's Hospital, Boston, MA, USA.,Department of Surgery, Harvard Medical School, Boston, MA, USA
| | - Dirk Strunk
- Experimental and Clinical Cell Therapy Institute, Paracelsus Medical University, Salzburg, Austria
| | - Marsha A Moses
- Vascular Biology Program, Boston Children's Hospital, Boston, MA, USA.,Department of Surgery, Harvard Medical School, Boston, MA, USA
| | - Michael Klagsbrun
- Vascular Biology Program, Boston Children's Hospital, Boston, MA, USA.,Department of Surgery, Harvard Medical School, Boston, MA, USA
| | - Joyce Bischoff
- Department of Surgery, Harvard Medical School, Boston, MA, USA.,Department of Pathology, Harvard Medical School, Boston, MA, USA
| | - Wolfgang F Graier
- Institute for Molecular Biology and Biochemistry, Medical University Graz, Graz, Austria
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19
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Patel S, Garapati C, Chowdhury P, Gupta H, Nesamony J, Nauli S, Boddu SH. Development and evaluation of dexamethasone nanomicelles with potential for treating posterior uveitis after topical application. J Ocul Pharmacol Ther 2015; 31:215-27. [PMID: 25839185 PMCID: PMC11075078 DOI: 10.1089/jop.2014.0152] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Accepted: 02/20/2015] [Indexed: 10/23/2022] Open
Abstract
PURPOSE This study aims at the development and preliminary evaluation of dexamethasone nanomicelles for treating posterior uveitis. Nanomicelles were formulated using polyoxyl 40 stearate (P40S) and polysorbate 80 (P80), which are approved by the FDA for ocular use. METHODS Dexamethasone nanomicelles were prepared and characterized for critical micellar concentration, solubility of dexamethasone, particle size, surface charge, morphology, in vitro drug release, clarity, stability, filtration efficiency, and sterility. Ocular tolerance and the tissue drug distribution of dexamethasone were assessed in rabbits after single and multiple topical administration. RESULTS Dexamethasone nanomicelles (0.1% w/v) were successfully developed and characterized with an optimized composition of P40S/P80=7/3 by weight. The mean diameter of blank and drug-loaded nanomicelles was 13.3±0.4 and 14.5±0.4 nm, respectively. Transmission electron microscopy images revealed the spherical structure of nanomicelles. Nanomicelles were found to be stable with respect to clarity, size and drug content at 4°C and 25°C for up to 6 months. No irritation or redness was observed in the treated eyes as compared with the untreated control rabbit eyes. Therapeutic concentrations of dexamethasone were observed in the retina and choroid after single and multiple topical application in rabbits. CONCLUSION In conclusion, the nanomicelles of P40S and P80 could efficiently solubilize 0.1% dexamethasone in their cores. The results also indicate that mixed nanomicelles could be utilized as a potential delivery system for delivering dexamethasone to treat the back of the eye diseases such as posterior uveitis after topical application.
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Affiliation(s)
- Soohi Patel
- Department of Pharmacy Practice, College of Pharmacy and Pharmaceutical Sciences, The University of Toledo, Toledo, Ohio
| | - Chandrasekhar Garapati
- Department of Pharmacy Practice, College of Pharmacy and Pharmaceutical Sciences, The University of Toledo, Toledo, Ohio
| | - Pallabita Chowdhury
- Department of Pharmacy Practice, College of Pharmacy and Pharmaceutical Sciences, The University of Toledo, Toledo, Ohio
| | - Himanshu Gupta
- Department of Pharmacy Practice, College of Pharmacy and Pharmaceutical Sciences, The University of Toledo, Toledo, Ohio
| | - Jerry Nesamony
- Department of Pharmacy Practice, College of Pharmacy and Pharmaceutical Sciences, The University of Toledo, Toledo, Ohio
| | - Surya Nauli
- Department of Pharmacology, The University of Toledo, Toledo, Ohio
| | - Sai H.S. Boddu
- Department of Pharmacy Practice, College of Pharmacy and Pharmaceutical Sciences, The University of Toledo, Toledo, Ohio
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20
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AlSuleimani YM, Hiley CR. The GPR55 agonist lysophosphatidylinositol relaxes rat mesenteric resistance artery and induces Ca(2+) release in rat mesenteric artery endothelial cells. Br J Pharmacol 2015; 172:3043-57. [PMID: 25652040 DOI: 10.1111/bph.13107] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Revised: 01/11/2015] [Accepted: 02/02/2015] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND AND PURPOSE Lysophosphatidylinositol (LPI), a lipid signalling molecule, activates GPR55 and elevates intracellular Ca(2+). Here, we examine the actions of LPI in the rat resistance mesenteric artery and Ca(2+) responses in endothelial cells isolated from the artery. EXPERIMENTAL APPROACH Vascular responses were studied using wire myographs. Single-cell fluorescence imaging was performed using a MetaFluor system. Hypotensive effects of LPI were assessed using a Biopac system. KEY RESULTS In isolated arteries, LPI-induced vasorelaxation was concentration- and endothelium-dependent and inhibited by CID 16020046, a GPR55 antagonist. The CB1 receptor antagonist AM 251 had no effect, whereas rimonabant and O-1918 significantly potentiated LPI responses. Vasorelaxation was reduced by charybdotoxin and iberiotoxin, alone or combined. LPI decreased systemic arterial pressure. GPR55 is expressed in rat mesenteric artery. LPI caused biphasic elevations of endothelial cell intracellular Ca(2+). Pretreatment with thapsigargin or 2-aminoethoxydiphenyl borate abolished both phases. The PLC inhibitor U73122 attenuated the initial phase and enhanced the second phase, whereas the Rho-associated kinase inhibitor Y-27632 abolished the late phase but not the early phase. CONCLUSIONS AND IMPLICATIONS LPI is an endothelium-dependent vasodilator in the rat small mesenteric artery and a hypotensive agent. The vascular response involves activation of Ca(2+)-sensitive K(+) channels and is not mediated by CB1 receptors, but unexpectedly enhanced by antagonists of the 'endothelial anandamide' receptor. In endothelial cells, LPI utilizes PLC-IP3 and perhaps ROCK-RhoA pathways to elevate intracellular Ca(2+). Overall, these findings support an endothelial site of action for LPI and suggest a possible role for GPR55 in vasculature.
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Affiliation(s)
- Y M AlSuleimani
- Department of Pharmacology, University of Cambridge, Cambridge, UK.,Department of Pharmacology and Clinical Pharmacy, College of Medicine and Health Sciences, Sultan Qaboos University, Alkoudh, Sultanate of Oman
| | - C R Hiley
- Department of Pharmacology, University of Cambridge, Cambridge, UK
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21
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Bondarenko AI. Endothelial atypical cannabinoid receptor: do we have enough evidence? Br J Pharmacol 2014; 171:5573-88. [PMID: 25073723 PMCID: PMC4290703 DOI: 10.1111/bph.12866] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2014] [Revised: 07/14/2014] [Accepted: 07/24/2014] [Indexed: 12/16/2022] Open
Abstract
Cannabinoids and their synthetic analogues affect a broad range of physiological functions, including cardiovascular variables. Although direct evidence is still missing, the relaxation of a vast range of vascular beds induced by cannabinoids is believed to involve a still unidentified non-CB1 , non-CB2 Gi/o protein-coupled receptor located on endothelial cells, the so called endothelial cannabinoid receptor (eCB receptor). Evidence for the presence of an eCB receptor comes mainly from vascular relaxation studies, which commonly employ pertussis toxin as an indicator for GPCR-mediated signalling. In addition, a pharmacological approach is widely used to attribute the relaxation to eCB receptors. Recent findings have indicated a number of GPCR-independent targets for both agonists and antagonists of the presumed eCB receptor, warranting further investigations and cautious interpretation of the vascular relaxation studies. This review will provide a brief historical overview on the proposed novel eCB receptor, drawing attention to the discrepancies between the studies on the pharmacological profile of the eCB receptor and highlighting the Gi/o protein-independent actions of the eCB receptor inhibitors widely used as selective compounds. As the eCB receptor represents an attractive pharmacological target for a number of cardiovascular abnormalities, defining its molecular identity and the extent of its regulation of vascular function will have important implications for drug discovery. This review highlights the need to re-evaluate this subject in a thoughtful and rigorous fashion. More studies are needed to differentiate Gi/o protein-dependent endothelial cannabinoid signalling from that involving the classical CB1 and CB2 receptors as well as its relevance for pathophysiological conditions.
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Affiliation(s)
- Alexander I Bondarenko
- Circulatory Physiology Department, O.O.Bogomoletz Institute of PhysiologyKiev, Ukraine
- Institute of Molecular Biology and Biochemistry, Medical University of GrazGraz, Austria
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Bondarenko AI, Drachuk K, Panasiuk O, Sagach V, Deak AT, Malli R, Graier WF. N-Arachidonoyl glycine suppresses Na⁺/Ca²⁺ exchanger-mediated Ca²⁺ entry into endothelial cells and activates BK(Ca) channels independently of GPCRs. Br J Pharmacol 2014; 169:933-48. [PMID: 23517055 PMCID: PMC3687672 DOI: 10.1111/bph.12180] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2012] [Revised: 01/14/2013] [Accepted: 02/20/2013] [Indexed: 02/03/2023] Open
Abstract
Background and Purpose N-arachidonoyl glycine (NAGly) is a lipoamino acid with vasorelaxant properties. We aimed to explore the mechanisms of NAGly's action on unstimulated and agonist-stimulated endothelial cells. Experimental Approach The effects of NAGly on endothelial electrical signalling were studied in combination with vascular reactivity. Key Results In EA.hy926 cells, the sustained hyperpolarization to histamine was inhibited by the non-selective Na+/Ca2+ exchanger (NCX) inhibitor bepridil and by an inhibitor of reversed mode NCX, KB-R7943. In cells dialysed with Cs+-based Na+-containing solution, the outwardly rectifying current with typical characteristics of NCX was augmented following histamine exposure, further increased upon external Na+ withdrawal and inhibited by bepridil. NAGly (0.3–30 μM) suppressed NCX currents in a URB597- and guanosine 5′-O-(2-thiodiphosphate) (GDPβS)-insensitive manner, [Ca2+]i elevation evoked by Na+ removal and the hyperpolarization to histamine. In rat aorta, NAGly opposed the endothelial hyperpolarization and relaxation response to ACh. In unstimulated EA.hy926 cells, NAGly potentiated the whole-cell current attributable to large-conductance Ca2+-activated K+ (BKCa) channels in a GDPβS-insensitive, paxilline-sensitive manner and produced a sustained hyperpolarization. In cell-free inside-out patches, NAGly stimulated single BKCa channel activity. Conclusion and Implications Our data showed that NCX is a Ca2+ entry pathway in endothelial cells and that NAGly is a potent G-protein-independent modulator of endothelial electrical signalling and has a dual effect on endothelial electrical responses. In agonist pre-stimulated cells, NAGly opposes hyperpolarization and relaxation via inhibition of NCX-mediated Ca2+ entry, while in unstimulated cells, it promotes hyperpolarization via receptor-independent activation of BKCa channels.
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Affiliation(s)
- Alexander I Bondarenko
- Institute of Molecular Biology and Biochemistry, Center of Molecular Medicine, Medical University of Graz, Graz, Austria.
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23
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Abstract
GPR55 belongs to the class A family of G-protein coupled receptor (GPCRs) and its activity is regulated by a range of synthetic and endogenous cannabinoids, and by lipid-derived ligands. Cannabinoids are known to be important in controlling appetite and metabolic balance, and it is now emerging that GPR55 may have a role to play in energy homeostasis through the regulation of food intake, fuel storage in adipocytes, gut motility and insulin secretion. This review summarises our current knowledge of expression and function of GPR55 in tissues involved in metabolic regulation, the signalling cascades through which GPR55 is reported to act to exert its effects, and it comments on the difficulties in reaching firm conclusions when using GPR55 ligands of poor specificity. Understanding the role of GPR55 in energy homeostasis may provide a novel target for therapeutic intervention in obesity and type 2 diabetes mellitus.
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Deak AT, Groschner LN, Alam MR, Seles E, Bondarenko AI, Graier WF, Malli R. The endocannabinoid N-arachidonoyl glycine (NAGly) inhibits store-operated Ca2+ entry by preventing STIM1-Orai1 interaction. J Cell Sci 2012; 126:879-88. [PMID: 23239024 DOI: 10.1242/jcs.118075] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The endocannabiniod anandamide (AEA) and its derivate N-arachidonoyl glycine (NAGly) have a broad spectrum of physiological effects, which are induced by both binding to receptors and receptor-independent modulations of ion channels and transporters. The impact of AEA and NAGly on store-operated Ca(2+) entry (SOCE), a ubiquitous Ca(2+) entry pathway regulating many cellular functions, is unknown. Here we show that NAGly, but not AEA reversibly hinders SOCE in a time- and concentration-dependent manner. The inhibitory effect of NAGly on SOCE was found in the human endothelial cell line EA.hy926, the rat pancreatic β-cell line INS-1 832/13, and the rat basophilic leukemia cell line RBL-2H3. NAGly diminished SOCE independently from the mode of Ca(2+) depletion of the endoplasmic reticulum, whereas it had no effect on Ca(2+) entry through L-type voltage-gated Ca(2+) channels. Enhanced Ca(2+) entry was effectively hampered by NAGly in cells overexpressing the key molecular constituents of SOCE, stromal interacting molecule 1 (STIM1) and the pore-forming subunit of SOCE channels, Orai1. Fluorescence microscopy revealed that NAGly did not affect STIM1 oligomerization, STIM1 clustering, or the colocalization of STIM1 with Orai1, which were induced by Ca(2+) depletion of the endoplasmic reticulum. In contrast, independently from its slow depolarizing effect on mitochondria, NAGly instantly and strongly diminished the interaction of STIM1 with Orai1, indicating that NAGly inhibits SOCE primarily by uncoupling STIM1 from Orai1. In summary, our findings revealed the STIM1-Orai1-mediated SOCE machinery as a molecular target of NAGly, which might have many implications in cell physiology.
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Affiliation(s)
- Andras T Deak
- Institute of Molecular Biology and Biochemistry, Center of Molecular Medicine, Medical University Graz, Graz, Austria
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25
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Grzelczyk A, Gendaszewska-Darmach E. Novel bioactive glycerol-based lysophospholipids: new data -- new insight into their function. Biochimie 2012; 95:667-79. [PMID: 23089136 DOI: 10.1016/j.biochi.2012.10.009] [Citation(s) in RCA: 115] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2012] [Accepted: 10/11/2012] [Indexed: 11/28/2022]
Abstract
Based on the results of research conducted over last two decades, lysophospholipids (LPLs) were observed to be not only structural components of cellular membranes but also biologically active molecules influencing a broad variety of processes such as carcinogenesis, neurogenesis, immunity, vascular development or regulation of metabolic diseases. With a growing interest in the involvement of extracellular lysophospholipids in both normal physiology and pathology, it has become evident that those small molecules may have therapeutic potential. While lysophosphatidic acid (LPA) and sphingosine-1-phosphate (S1P) have been studied in detail, other LPLs such as lysophosphatidylglycerol (LPG), lysophosphatidylserine (LPS), lysophosphatidylinositol (LPI), lysophosphatidylethanolamine (LPE) or even lysophosphatidylcholine (LPC) have not been elucidated to such a high degree. Although information concerning the latter LPLs is sparse as compared to LPA and S1P, within the last couple of years much progress has been made. Recently published data suggest that these compounds may regulate fundamental cellular activities by modulating multiple molecular targets, e.g. by binding to specific receptors and/or altering the structure and fluidity of lipid rafts. Therefore, the present review is devoted to novel bioactive glycerol-based lysophospholipids and recent findings concerning their functions and possible signaling pathways regulating physiological and pathological processes.
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Affiliation(s)
- Anna Grzelczyk
- Institute of Technical Biochemistry, Faculty of Biotechnology and Food Sciences, Lodz University of Technology, Stefanowskiego 4/10, 90-924 Lodz, Poland
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Lysophosphatidylinositol signalling: New wine from an old bottle. Biochim Biophys Acta Mol Cell Biol Lipids 2012; 1821:694-705. [DOI: 10.1016/j.bbalip.2012.01.009] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2011] [Revised: 12/02/2011] [Accepted: 01/03/2012] [Indexed: 01/29/2023]
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Henstridge CM, Balenga NAB, Kargl J, Andradas C, Brown AJ, Irving A, Sanchez C, Waldhoer M. Minireview: recent developments in the physiology and pathology of the lysophosphatidylinositol-sensitive receptor GPR55. Mol Endocrinol 2011; 25:1835-48. [PMID: 21964594 PMCID: PMC5417173 DOI: 10.1210/me.2011-1197] [Citation(s) in RCA: 123] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2011] [Accepted: 09/01/2011] [Indexed: 11/19/2022] Open
Abstract
Emerging data suggest that off-target cannabinoid effects may be mediated via novel seven-transmembrane spanning/G protein-coupled receptors. Due to its cannabinoid sensitivity, the G protein-coupled receptor 55 (GPR55) was recently proposed as a candidate; however, GPR55 is phylogenetically distinct from the traditional cannabinoid receptors, and the conflicting pharmacology, signaling, and functional data have prevented its classification as a novel cannabinoid receptor. Indeed, the most consistent and potent agonist to date is the noncannabinoid lysophospholipid, lysophosphatidylinositol. Here we present new human GPR55 mRNA expression data, providing supportive evidence of GPR55 expression in a vast array of tissues and cell types. Moreover, we summarize major recent developments in GPR55 research and aim to update the reader in the rapidly expanding fields of GPR55 pharmacology, physiology, and pathology.
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