1
|
Brollo M, Salvator H, Grassin-Delyle S, Glorion M, Descamps D, Buenestado A, Naline E, Tenor H, Tiotiu A, Devillier P. The IL-4/13-induced production of M2 chemokines by human lung macrophages is enhanced by adenosine and PGE 2. Int Immunopharmacol 2024; 128:111557. [PMID: 38266451 DOI: 10.1016/j.intimp.2024.111557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 01/12/2024] [Accepted: 01/15/2024] [Indexed: 01/26/2024]
Abstract
BACKGROUND AND PURPOSE Lung macrophages (LMs) are critically involved in respiratory diseases. The primary objective of the present study was to determine whether or not an adenosine analog (NECA) and prostaglandin E2 (PGE2) affected the interleukin (IL)-4- and IL-13-induced release of M2a chemokines (CCL13, CCL17, CCL18, and CCL22) by human LMs. EXPERIMENTAL APPROACH Primary macrophages isolated from resected human lungs were incubated with NECA, PGE2, roflumilast, or vehicle and stimulated with IL-4 or IL-13 for 24 h. The levels of chemokines and PGE2 in the culture supernatants were measured using ELISAs and enzyme immunoassays. KEY RESULTS Exposure to IL-4 (10 ng/mL) and IL-13 (50 ng/mL) was associated with greater M2a chemokine production but not PGE2 production. PGE2 (10 ng/mL) and NECA (10-6 M) induced the production of M2a chemokines to a lesser extent but significantly enhanced the IL-4/IL-13-induced production of these chemokines. At either a clinically relevant concentration (10-9 M) or at a concentration (10-7 M) that fully inhibited phosphodiesterase 4 (PDE4) activity, roflumilast did not increase the production of M2a chemokines and did not modulate their IL-13-induced production, regardless of the presence or absence of PGE2. CONCLUSIONS NECA and PGE2 enhanced the IL-4/IL-13-induced production of M2a chemokines. The inhibition of PDE4 by roflumilast did not alter the production of these chemokines. These results contrast totally with the previously reported inhibitory effects of NECA, PGE2, and PDE4 inhibitors on the lipopolysaccharide-induced release of tumor necrosis factor alpha and M1 chemokines in human LMs.
Collapse
Affiliation(s)
- Marion Brollo
- Laboratory of Research in Respiratory Pharmacology, Faculté des Sciences de la Vie Simone Veil, VIM, UMR-0892, INRAE, UVSQ, Université Paris-Saclay, France
| | - Hélène Salvator
- Laboratory of Research in Respiratory Pharmacology, Faculté des Sciences de la Vie Simone Veil, VIM, UMR-0892, INRAE, UVSQ, Université Paris-Saclay, France; Department of Airway Diseases, Respiratory Pharmacology Unit, Foch Hospital, Suresnes, France
| | - Stanislas Grassin-Delyle
- Department of Airway Diseases, Respiratory Pharmacology Unit, Foch Hospital, Suresnes, France; Department of Airway Diseases, Thoracic surgery, Foch Hospital, Suresnes, France
| | - Mathieu Glorion
- Laboratory of Research in Respiratory Pharmacology, Faculté des Sciences de la Vie Simone Veil, VIM, UMR-0892, INRAE, UVSQ, Université Paris-Saclay, France; INSERM U1173, Infection & Inflammation, Département de Biotechnologie de la Santé, Université Paris-Saclay, Montigny-le-Bretonneux, France
| | - Delphyne Descamps
- VIM, UMR-0892, INRAE, UVSQ, Université Paris-Saclay, Jouy-en-Josas, France
| | - Amparo Buenestado
- Laboratory of Research in Respiratory Pharmacology, Faculté des Sciences de la Vie Simone Veil, VIM, UMR-0892, INRAE, UVSQ, Université Paris-Saclay, France
| | - Emmanuel Naline
- Laboratory of Research in Respiratory Pharmacology, Faculté des Sciences de la Vie Simone Veil, VIM, UMR-0892, INRAE, UVSQ, Université Paris-Saclay, France; Department of Airway Diseases, Respiratory Pharmacology Unit, Foch Hospital, Suresnes, France
| | | | - Angelica Tiotiu
- Department of Pulmonary Medicine, University Hospital Saint-Luc, Institut of Experimental and Clinical Research (IREC), University of Louvain, Brussels, Belgium
| | - Philippe Devillier
- Laboratory of Research in Respiratory Pharmacology, Faculté des Sciences de la Vie Simone Veil, VIM, UMR-0892, INRAE, UVSQ, Université Paris-Saclay, France; Department of Airway Diseases, Respiratory Pharmacology Unit, Foch Hospital, Suresnes, France.
| |
Collapse
|
2
|
Giffney HE, Cummins EP, Murphy EP, Brayden DJ, Crean D. Protein kinase D, ubiquitin and proteasome pathways are involved in adenosine receptor-stimulated NR4A expression in myeloid cells. Biochem Biophys Res Commun 2021; 555:19-25. [PMID: 33812054 DOI: 10.1016/j.bbrc.2021.03.082] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 03/10/2021] [Accepted: 03/15/2021] [Indexed: 01/12/2023]
Abstract
Adenosine is a purine nucleoside pivotal for homeostasis in cells and tissues. Stimulation of the adenosine receptors (AR) has been shown to regulate the nuclear orphan receptor 4A (NR4A1-3) family, resulting in attenuation of hyper-inflammatory responses in myeloid cells. The NR4A1-3 orphan receptors are early immediate response genes and transcriptional regulators of cell and tissue homeostasis. The signal transduction and transcriptional mechanism(s) of how AR-stimulation promotes NR4A expression in myeloid cells is unknown and is the focus of this study. We confirm that adenosine and the stable analogue, 5'-N-Ethylcarboxamidoadenosine (NECA), enhance NR4A1-3 expression in THP-1 cells. Pharmacological approaches identified that protein kinase D (PKD) mediates AR-stimulated NR4A expression in myeloid cells and reveals no involvement of PKA nor PKC. The role of NF-κB, a principal regulator of NR4A expression in myeloid cells, was examined as a possible transcriptional regulator downstream of PKD. Utilising BAY11-7082 and MG-132, inhibitors of the respective ubiquitin and proteasome pathways essential for NF-κB activation, suggested a prospective role for NF-κB, or more specifically signalling via IKKα/β. However, biological interventional studies using overexpression of IκBα in myeloid cells and MEF cells lacking IKKα and IKKβ (IKKα/β-/-) revealed the NF-κB pathway is not utilised in mediating AR-stimulated NR4A expression. Thus, this study contributes mechanistic insight into how AR signalling modulates the expression of NR4A receptors, pivotal regulators of inflammatory responses in myeloid cells.
Collapse
Affiliation(s)
- Hugh E Giffney
- School of Veterinary Medicine, University College Dublin, Ireland; UCD Conway Institute, University College Dublin, Ireland
| | - Eoin P Cummins
- UCD Conway Institute, University College Dublin, Ireland; UCD School of Medicine, University College Dublin, Ireland
| | | | - David J Brayden
- School of Veterinary Medicine, University College Dublin, Ireland; UCD Conway Institute, University College Dublin, Ireland
| | - Daniel Crean
- School of Veterinary Medicine, University College Dublin, Ireland; UCD Conway Institute, University College Dublin, Ireland.
| |
Collapse
|
3
|
Polak D, Talar M, Wolska N, Wojkowska DW, Karolczak K, Kramkowski K, Bonda TA, Watala C, Przygodzki T. Adenosine Receptor Agonist HE-NECA Enhances Antithrombotic Activities of Cangrelor and Prasugrel in vivo by Decreasing of Fibrinogen Density in Thrombus. Int J Mol Sci 2021; 22:3074. [PMID: 33802928 PMCID: PMC8002731 DOI: 10.3390/ijms22063074] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 03/11/2021] [Accepted: 03/15/2021] [Indexed: 02/04/2023] Open
Abstract
Blood platelets' adenosine receptors (AR) are considered to be a new target for the anti-platelet therapy. This idea is based on in vitro studies which show that signaling mediated by these receptors leads to a decreased platelet response to activating stimuli. In vivo evidence for the antithrombotic activity of AR agonists published to date were limited, however, to the usage of relatively high doses given in bolus. The present study was aimed at verifying if these substances used in lower doses in combination with inhibitors of P2Y12 could serve as components of dual anti-platelet therapy. We have found that a selective A2A agonist 2-hexynyl-5'-N-ethylcarboxamidoadenosine (HE-NECA) improved the anti-thrombotic properties of either cangrelor or prasugrel in the model of ferric chloride-induced experimental thrombosis in mice. Importantly, HE-NECA was effective not only when applied in bolus as other AR agonists in the up-to-date published studies, but also when given chronically. In vitro thrombus formation under flow conditions revealed that HE-NECA enhanced the ability of P2Y12 inhibitors to decrease fibrinogen content in thrombi, possibly resulting in their lower stability. Adenosine receptor agonists possess a certain hypotensive effect and an ability to increase the blood-brain barrier permeability. Therefore, the effects of anti-thrombotic doses of HE-NECA on blood pressure and the blood-brain barrier permeability in mice were tested. HE-NECA applied in bolus caused a significant hypotension in mice, but the effect was much lower when the substance was given in doses corresponding to that obtained by chronic administration. At the same time, no significant effect of HE-NECA was observed on the blood-brain barrier. We conclude that chronic administration of the A2A agonist can be considered a potential component of a dual antithrombotic therapy. However, due to the hypotensive effect of the substances, dosage and administration must be elaborated to minimize the side-effects. The total number of animals used in the experiments was 146.
Collapse
Affiliation(s)
- Dawid Polak
- Department of Haemostasis and Haemostatic Disorders, Chair of Biomedical Sciences, Medical University of Lodz, Mazowiecka 6/8, 92-235 Lodz, Poland; (D.P.); (M.T.); (N.W.); (D.W.W.); (K.K.); (C.W.)
| | - Marcin Talar
- Department of Haemostasis and Haemostatic Disorders, Chair of Biomedical Sciences, Medical University of Lodz, Mazowiecka 6/8, 92-235 Lodz, Poland; (D.P.); (M.T.); (N.W.); (D.W.W.); (K.K.); (C.W.)
| | - Nina Wolska
- Department of Haemostasis and Haemostatic Disorders, Chair of Biomedical Sciences, Medical University of Lodz, Mazowiecka 6/8, 92-235 Lodz, Poland; (D.P.); (M.T.); (N.W.); (D.W.W.); (K.K.); (C.W.)
| | - Dagmara W. Wojkowska
- Department of Haemostasis and Haemostatic Disorders, Chair of Biomedical Sciences, Medical University of Lodz, Mazowiecka 6/8, 92-235 Lodz, Poland; (D.P.); (M.T.); (N.W.); (D.W.W.); (K.K.); (C.W.)
| | - Kamil Karolczak
- Department of Haemostasis and Haemostatic Disorders, Chair of Biomedical Sciences, Medical University of Lodz, Mazowiecka 6/8, 92-235 Lodz, Poland; (D.P.); (M.T.); (N.W.); (D.W.W.); (K.K.); (C.W.)
| | - Karol Kramkowski
- Department of Physical Chemistry, Medical University of Bialystok, Mickiewicza 2A, 15-089 Bialystok, Poland;
| | - Tomasz A. Bonda
- Department of General and Experimental Pathology, Medical University of Bialystok, Mickiewicza 2C, 15-222 Bialystok, Poland;
| | - Cezary Watala
- Department of Haemostasis and Haemostatic Disorders, Chair of Biomedical Sciences, Medical University of Lodz, Mazowiecka 6/8, 92-235 Lodz, Poland; (D.P.); (M.T.); (N.W.); (D.W.W.); (K.K.); (C.W.)
| | - Tomasz Przygodzki
- Department of Haemostasis and Haemostatic Disorders, Chair of Biomedical Sciences, Medical University of Lodz, Mazowiecka 6/8, 92-235 Lodz, Poland; (D.P.); (M.T.); (N.W.); (D.W.W.); (K.K.); (C.W.)
| |
Collapse
|
4
|
Przygodzki T, Wolska N, Talar M, Polak D, Gapinska M, Watala C. Comparison of different microscopy approaches to quantification of inhibitory effect on thrombus formation under flow conditions by the example of adenosine receptor agonist HE-NECA. J Pharmacol Toxicol Methods 2018; 94:94-104. [PMID: 30031827 DOI: 10.1016/j.vascn.2018.07.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Revised: 06/18/2018] [Accepted: 07/17/2018] [Indexed: 12/31/2022]
Abstract
INTRODUCTION Thrombus formation in vitro in flow conditions and its visualization and quantification with the use of microscopy are widely utilized to evaluate activity of compounds with a potential antithrombotic activity. Visualization and quantification of thrombi can be performed with the use of wide-field or confocal microscopy. Acquiring reliable numerical data from wide-field microscopy images of objects which have a complex three-dimensional structure is strongly influenced by the methods used for image analysis. This can be a possible source of inaccuracy in assessment of antithrombotic activity of a tested substance. We aimed to verify how different approaches to the quantification of wide-field images can affect the evaluation of an antiplatelet effect of a tested substance. METHODS We compared three algorithms of image analysis to evaluate an effect of 2-hexynyl-5'-ethylcarboxamidoadenosine (HE-NECA), a compound of a moderate antiplatelet activity on thrombus formation, and of abciximab - a potent antiplatelet compound. Also, we studied how the results obtained in a wide-field imaging correspond to those obtained by means of confocal imaging. RESULTS Three algorithms for analysis of wide-field images showed antiplatelet effect of HE-NECA or abciximab. Absolute values of thrombus area and outcomes of the evaluation of inhibition efficacy of HE-NECA were significantly different between the algorithms. Analysis of volumes and heights of thrombi obtained by confocal imaging confirmed inhibitory effect of HE-NECA, but the evaluated levels of inhibition were significantly different from that obtained by wide-field imaging. DISCUSSION We conclude that wide-field imaging provides reliable qualitative data on an inhibitory effect on thrombus formation, despite differences which can emerge from various approaches to image analysis. However, quantitative evaluation and comparison of the efficacy of inhibitors on the basis of total area occupied by thrombi obtained by wide-field microscopy should be made with caution. To obtain a reliable quantitative assessment of the effect of a tested compound on thrombus structure the use of confocal microscopy is inevitable.
Collapse
Affiliation(s)
- Tomasz Przygodzki
- Department of Haemostatic Disorders, Chair of Biomedical Sciences, Faculty of Health Sciences, Medical University of Lodz, 6/8 Mazowiecka Street, 92-235 Lodz, Poland.
| | - Nina Wolska
- Department of Haemostatic Disorders, Chair of Biomedical Sciences, Faculty of Health Sciences, Medical University of Lodz, 6/8 Mazowiecka Street, 92-235 Lodz, Poland
| | - Marcin Talar
- Department of Haemostatic Disorders, Chair of Biomedical Sciences, Faculty of Health Sciences, Medical University of Lodz, 6/8 Mazowiecka Street, 92-235 Lodz, Poland
| | - Dawid Polak
- Department of Haemostatic Disorders, Chair of Biomedical Sciences, Faculty of Health Sciences, Medical University of Lodz, 6/8 Mazowiecka Street, 92-235 Lodz, Poland
| | - Magdalena Gapinska
- Laboratory of Microscopic Imaging and Specialized Biological Techniques, Faculty of Biology and Environmental Protection, University of Lodz, 12/16 Banacha Street, 90-237 Lodz, Poland
| | - Cezary Watala
- Department of Haemostatic Disorders, Chair of Biomedical Sciences, Faculty of Health Sciences, Medical University of Lodz, 6/8 Mazowiecka Street, 92-235 Lodz, Poland
| |
Collapse
|
5
|
Aamodt KI, Aramandla R, Brown JJ, Fiaschi-Taesch N, Wang P, Stewart AF, Brissova M, Powers AC. Development of a reliable automated screening system to identify small molecules and biologics that promote human β-cell regeneration. Am J Physiol Endocrinol Metab 2016; 311:E859-E868. [PMID: 27624103 PMCID: PMC5130356 DOI: 10.1152/ajpendo.00515.2015] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Accepted: 09/09/2016] [Indexed: 11/22/2022]
Abstract
Numerous compounds stimulate rodent β-cell proliferation; however, translating these findings to human β-cells remains a challenge. To examine human β-cell proliferation in response to such compounds, we developed a medium-throughput in vitro method of quantifying adult human β-cell proliferation markers. This method is based on high-content imaging of dispersed islet cells seeded in 384-well plates and automated cell counting that identifies fluorescently labeled β-cells with high specificity using both nuclear and cytoplasmic markers. β-Cells from each donor were assessed for their function and ability to enter the cell cycle by cotransduction with adenoviruses encoding cell cycle regulators cdk6 and cyclin D3. Using this approach, we tested 12 previously identified mitogens, including neurotransmitters, hormones, growth factors, and molecules, involved in adenosine and Tgf-1β signaling. Each compound was tested in a wide concentration range either in the presence of basal (5 mM) or high (11 mM) glucose. Treatment with the control compound harmine, a Dyrk1a inhibitor, led to a significant increase in Ki-67+ β-cells, whereas treatment with other compounds had limited to no effect on human β-cell proliferation. This new scalable approach reduces the time and effort required for sensitive and specific evaluation of human β-cell proliferation, thus allowing for increased testing of candidate human β-cell mitogens.
Collapse
Affiliation(s)
- Kristie I Aamodt
- Department of Molecular Physiology and Biophysics, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Radhika Aramandla
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Judy J Brown
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Nathalie Fiaschi-Taesch
- Division of Endocrinology, Diabetes, and Bone Disease, Department of Medicine, Mount Sinai Medical Center, New York, New York; and
| | - Peng Wang
- Division of Endocrinology, Diabetes, and Bone Disease, Department of Medicine, Mount Sinai Medical Center, New York, New York; and
| | - Andrew F Stewart
- Division of Endocrinology, Diabetes, and Bone Disease, Department of Medicine, Mount Sinai Medical Center, New York, New York; and
| | - Marcela Brissova
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee;
| | - Alvin C Powers
- Department of Molecular Physiology and Biophysics, Vanderbilt University Medical Center, Nashville, Tennessee
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
- Veterans Affairs Tennessee Valley Healthcare System, Nashville, Tennessee
| |
Collapse
|
6
|
Iur'eva KS, Nevskaia KV, Dziuman AN, Ikkert OP, Ivanov VV, Saltykova IV, Sazonov AÉ, Ogorodova LM. [Stimulation of adenosine receptors on myeloid cells enhance leukocyte migration at the site of burn injury]. Biomed Khim 2014; 60:246-57. [PMID: 24837313 DOI: 10.18097/pbmc20146002246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Adenosine, endogenous purine nucleoside, is an ATP metabolite that also acts as an extracellular signaling molecule. The concentration of extracellular adenosine rises during hypoxia and cell damage leading to numerous pleiotropic effects. Although a high concentration of adenosine was found at burn injury, the effect has not been well elucidated. We have studied human peripheral blood myeloid cell, due to their expression of specific adenosine receptors and capacity to migrate to the site of burn injury. We have shown that myeloid cells after 72 hours of stimulation of adenosine receptors develop altered expression of surface antigens: preserved monocyte's marker CD14 with already expressed dendritic cell markers (CD209, CD1a). Whereas untreated cells have already lost monocyte marker in 72 hours, and express CD1a more abundantly. Adenosine modified myeloid cells express also higher levels of mRNA of proinflammatory cytokines and chemoattractants (IL-6, IL-8, IL-1 b). Using mouse model of the burn injury we have shown, that adenosine modified bone marrow derived myeloid cells injected in the site of the injury promote migration of granulocytes, monocytes, macrophages, and fibroblasts on the 7th day after burn. Thus, stimulation of adenosine receptors alters differentiation and function of myeloid cells. In the site of burn injury adenosine modified myeloid cells augment cell migration due to paracrine factors.
Collapse
|
7
|
Acurio J, Troncoso F, Bertoglia P, Salomon C, Aguayo C, Sobrevia L, Escudero C. Potential role of A2B adenosine receptors on proliferation/migration of fetal endothelium derived from preeclamptic pregnancies. Biomed Res Int 2014; 2014:274507. [PMID: 24877077 PMCID: PMC4024414 DOI: 10.1155/2014/274507] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Accepted: 04/01/2014] [Indexed: 01/10/2023]
Abstract
To investigate the functionality of A2B adenosine receptor (A2BAR) and the nitric oxide (NO) and vascular endothelial growth factor (VEGF) signaling pathway in the endothelial cell proliferation/migration during preeclampsia, we used human umbilical vein endothelial cells (HUVECs) isolated from normal pregnancies (n = 15) or pregnancies with preeclampsia (n = 15). Experiments were performed in presence or absence of the nonselective adenosine receptor agonist NECA, the A2BAR selective antagonist MRS-1754, and the nitric oxide synthase (NOS) inhibitor L-NAME. Results indicated that cells from preeclampsia exhibited a significant higher protein level of A2BAR and logEC50 for NECA-mediated proliferation than normotensive pregnancies. The stimulatory effect of NECA (10 μM, 24 h) on cell proliferation was prevented by MRS-1754 (5 nM) coincubation only in cells from normotensive pregnancies. Nevertheless, L-NAME (100 μM, 24 h) reduced the NECA-induced cell proliferation/migration in HUVEC from normal pregnancy; however in preeclampsia only NECA-induced cell proliferation was reduced by L-NAME. Moreover, NECA increased protein nitration and abundance of VEGF in cells from normal pregnancy and effect prevented by MRS-1754 coincubation. Nevertheless, in preeclampsia NECA did not affect the protein level of VEGF. In conclusion HUVECs from preeclampsia exhibit elevated protein level of A2BAR and impairment of A2BAR-mediated NO/VEGF signaling pathway.
Collapse
Affiliation(s)
- Jesenia Acurio
- Vascular Physiology Laboratory, Group of Investigation in Tumor Angiogenesis (GIANT), Group of Research and Innovation in Vascular Health (GRIVAS Health), Department of Basic Sciences, Faculty of Sciences, Universidad del Bío-Bío, Chillán, Chile
| | - Felipe Troncoso
- Vascular Physiology Laboratory, Group of Investigation in Tumor Angiogenesis (GIANT), Group of Research and Innovation in Vascular Health (GRIVAS Health), Department of Basic Sciences, Faculty of Sciences, Universidad del Bío-Bío, Chillán, Chile
| | - Patricio Bertoglia
- Vascular Physiology Laboratory, Group of Investigation in Tumor Angiogenesis (GIANT), Group of Research and Innovation in Vascular Health (GRIVAS Health), Department of Basic Sciences, Faculty of Sciences, Universidad del Bío-Bío, Chillán, Chile
- Obstetrics and Gynecology Department, Herminda Martin Clinical Hospital, Chillan, Chile
| | - Carlos Salomon
- University of Queensland Centre for Clinical Research (UQCCR), Faculty of Medicine and Biomedical Sciences, University of Queensland, Herston, QLD 4006, Australia
| | - Claudio Aguayo
- Department of Clinical Biochemistry and Immunology, Faculty of Pharmacy, University of Concepción, Chile
| | - Luis Sobrevia
- University of Queensland Centre for Clinical Research (UQCCR), Faculty of Medicine and Biomedical Sciences, University of Queensland, Herston, QLD 4006, Australia
- Cellular and Molecular Physiology Laboratory (CMPL), Division of Obstetrics and Gynecology, Faculty of Medicine, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Carlos Escudero
- Vascular Physiology Laboratory, Group of Investigation in Tumor Angiogenesis (GIANT), Group of Research and Innovation in Vascular Health (GRIVAS Health), Department of Basic Sciences, Faculty of Sciences, Universidad del Bío-Bío, Chillán, Chile
| |
Collapse
|
8
|
Gohar EY, El-gowilly SM, El-Gowelli HM, El-Demellawy MA, El-Mas MM. PI3K/Akt-independent NOS/HO activation accounts for the facilitatory effect of nicotine on acetylcholine renal vasodilations: modulation by ovarian hormones. PLoS One 2014; 9:e95079. [PMID: 24733557 PMCID: PMC3986343 DOI: 10.1371/journal.pone.0095079] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2013] [Accepted: 03/24/2014] [Indexed: 12/21/2022] Open
Abstract
We investigated the effect of chronic nicotine on cholinergically-mediated renal vasodilations in female rats and its modulation by the nitric oxide synthase (NOS)/heme oxygenase (HO) pathways. Dose-vasodilatory response curves of acetylcholine (0.01–2.43 nmol) were established in isolated phenylephrine-preconstricted perfused kidneys obtained from rats treated with or without nicotine (0.5–4.0 mg/kg/day, 2 weeks). Acetylcholine vasodilations were potentiated by low nicotine doses (0.5 and 1 mg/kg/day) in contrast to no effect for higher doses (2 and 4 mg/kg/day). The facilitatory effect of nicotine was acetylcholine specific because it was not observed with other vasodilators such as 5′-N-ethylcarboxamidoadenosine (NECA, adenosine receptor agonist) or papaverine. Increases in NOS and HO-1 activities appear to mediate the nicotine-evoked enhancement of acetylcholine vasodilation because the latter was compromised after pharmacologic inhibition of NOS (L-NAME) or HO-1 (zinc protoporphyrin, ZnPP). The renal protein expression of phosphorylated Akt was not affected by nicotine. We also show that the presence of the two ovarian hormones is necessary for the nicotine augmentation of acetylcholine vasodilations to manifest because nicotine facilitation was lost in kidneys of ovariectomized (OVX) and restored after combined, but not individual, supplementation with medroxyprogesterone acetate (MPA) and estrogen (E2). Together, the data suggests that chronic nicotine potentiates acetylcholine renal vasodilation in female rats via, at least partly, Akt-independent HO-1 upregulation. The facilitatory effect of nicotine is dose dependent and requires the presence of the two ovarian hormones.
Collapse
Affiliation(s)
- Eman Y. Gohar
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt
| | - Sahar M. El-gowilly
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt
| | - Hanan M. El-Gowelli
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt
| | - Maha A. El-Demellawy
- Medical Biotechnology Department, City for Scientific Research & Technology Applications, Borg El-Arab, Alexandria, Egypt
| | - Mahmoud M. El-Mas
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt
- * E-mail:
| |
Collapse
|
9
|
Ehrentraut H, Westrich JA, Eltzschig HK, Clambey ET. Adora2b adenosine receptor engagement enhances regulatory T cell abundance during endotoxin-induced pulmonary inflammation. PLoS One 2012; 7:e32416. [PMID: 22389701 PMCID: PMC3289657 DOI: 10.1371/journal.pone.0032416] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2011] [Accepted: 01/30/2012] [Indexed: 01/01/2023] Open
Abstract
Anti-inflammatory signals play an essential role in constraining the magnitude of an inflammatory response. Extracellular adenosine is a critical tissue-protective factor, limiting the extent of inflammation. Given the potent anti-inflammatory effects of extracellular adenosine, we sought to investigate how extracellular adenosine regulates T cell activation and differentiation. Adenosine receptor activation by a pan adenosine-receptor agonist enhanced the abundance of murine regulatory T cells (Tregs), a cell type critical in constraining inflammation. Gene expression studies in both naïve CD4 T cells and Tregs revealed that these cells expressed multiple adenosine receptors. Based on recent studies implicating the Adora2b in endogenous anti-inflammatory responses during acute inflammation, we used a pharmacologic approach to specifically activate Adora2b. Indeed, these studies revealed robust enhancement of Treg differentiation in wild-type mice, but not in Adora2b−/− T cells. Finally, when we subjected Adora2b-deficient mice to endotoxin-induced pulmonary inflammation, we found that these mice experienced more severe inflammation, characterized by increased cell recruitment and increased fluid leakage into the airways. Notably, Adora2b-deficient mice failed to induce Tregs after endotoxin-induced inflammation and instead had an enhanced recruitment of pro-inflammatory effector T cells. In total, these data indicate that the Adora2b adenosine receptor serves a potent anti-inflammatory role, functioning at least in part through the enhancement of Tregs, to limit inflammation.
Collapse
Affiliation(s)
| | | | | | - Eric T. Clambey
- Mucosal Inflammation Program, Department of Anesthesiology, University of Colorado Denver, Aurora, Colorado, United States of America
- * E-mail:
| |
Collapse
|
10
|
Owen SJ, Massa HH, Rose'Meyer RB. Loss of adenosine A2B receptor mediated relaxant responses in the aged female rat bladder; effects of dietary phytoestrogens. Naunyn Schmiedebergs Arch Pharmacol 2012; 385:539-49. [PMID: 22237834 DOI: 10.1007/s00210-011-0722-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2011] [Accepted: 12/22/2011] [Indexed: 12/12/2022]
Abstract
This study examined the effect of age, ovariectomy and dietary phytoestrogen ingestion on adenosine A(2B) receptor mediated relaxant responses and mRNA expression of adenosine receptor subtypes in the rat isolated bladder. Female Wistar rats (8 weeks) were anaesthetised and the ovaries were removed (ovx) or left intact (sham). Rats were fed either normal rat chow (soy, phytoestrogens) or a non-soy (phytoestrogen free) diet. Isolated bladder from rats aged 12, 24 or 52 weeks were pre-contracted with 3 μM carbachol prior to a concentration response curve to 5'-(N-ethylcarboxamido) adenosine (NECA) being obtained. In 12-week-old rats, the bladder exhibited enhanced relaxant responses to NECA in soy-fed rats (P < 0.05), whilst at 24 weeks of age, the relaxant responses to NECA were attenuated in all the groups studied except soy-treated sham rat bladders in which the relaxant responses were enhanced. At 52 weeks of age, no relaxant effects were observed in any of the treatment groups and NECA-induced contractile responses occurred. In all bladders, the adenosine A(2B) receptor was the most abundantly expressed. In bladders from young and mature female rats, the mRNA expression of adenosine receptors (A(1), A(2A) and A(2B)) was lowest in the bladder from non-soy-fed ovariectomised animals and the use of phytoestrogens in the diet increased the mRNA expression of these receptors (P < 0.05). While a soy diet improves the relaxant effects to the adenosine analogue via adenosine A(2B) receptors in bladders from younger rats, the benefits are lost with advancing age.
Collapse
Affiliation(s)
- Suzzanne J Owen
- School of Medical Sciences, Griffith University, Gold Coast Campus, Queensland, 4222, Australia
| | | | | |
Collapse
|
11
|
Kovárů H, Kováru F, Lisá V. Effect of fluoxetine and adenosine receptor NECA agonist on G alpha q/11 protein of C6 glioma cells. Neuro Endocrinol Lett 2012; 33:614-618. [PMID: 23160219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Accepted: 10/07/2012] [Indexed: 06/01/2023]
Abstract
OBJECTIVES Trimeric G-proteins play a crucial role in the transmembrane signalling to intracellular pathways via effector phospholipase C (1,4,5 IP3) or adenylylcyclase (cAMP). G-protein modulation is considered to participate in the antidepressant mode of action by neurotransmitter G-protein coupled receptors (GPCR). Adenosine is naturally occured nucleoside and adenosine receptor belongs to GPCR family. Properties and functions of ubiquitous adenosine receptor were described with number of agonists and antagonists. METHODS In C6 glioma cells, we studied acute administration of SSRI antidepressants - fluoxetine, sertraline and citalopram. We used immunochemical estimation (ELISA) of the main types of G-protein alpha subunits from isolated membranes of C6 glioma cells. We also estimated effect of NECA agonist on fluoxetine induced signalling via 1,4,5 IP3 and its levels. RESULTS Results show involvement of the antidepressant drugs in the C6 glioma signal transduction cascades and their modulation in dependence on the antidepressant of SSRI type. We measured main G alpha protein profiles after fluoxetine, sertraline and citalopram administration. We found significant changes as following: decreased G alpha Gq/11 for fluoxetine, low G alpha s for sertraline and both high G alpha q/11 and high G alpha s for citalopram. Furthermore the NECA (5´-N-ethylcarboxamido- adenosine) agonist of adenosine receptor alone evoked high decrease of G alpha q/11 levels. Whereas fluoxetine influenced G alpha q/11 decline was abolished by NECA in concentration manner, especially at 10-8 and 10-9 M concentrations. These results support abolishion NECA effect on fluoxetin influenced 1,4,5 IP3 signalling via PLC. CONCLUSION Main G alpha profiles are dependent on SSRI type antidepressant. Abolishing both fluoxetine evoked G alpha q/11 and and 1,4,5 IP3 signalling can indicate parallel interference between G-protein coupled receptors (GPCR) and the cell response. Presented data are first findings about adenosine receptor interaction with fluoxetine signalling. Thus in vitro studies contribute to the clarification of the molecular basis of antidepressant action.
Collapse
Affiliation(s)
- Hana Kovárů
- 1st Faculty of Medicine, Charles University in Prague, Prague, Czech Republic.
| | | | | |
Collapse
|
12
|
Csóka B, Selmeczy Z, Koscsó B, Németh ZH, Pacher P, Murray PJ, Kepka-Lenhart D, Morris SM, Gause WC, Leibovich SJ, Haskó G. Adenosine promotes alternative macrophage activation via A2A and A2B receptors. FASEB J 2012; 26:376-86. [PMID: 21926236 PMCID: PMC3250237 DOI: 10.1096/fj.11-190934] [Citation(s) in RCA: 286] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2011] [Accepted: 09/01/2011] [Indexed: 01/04/2023]
Abstract
Adenosine has been implicated in suppressing the proinflammatory responses of classically activated macrophages induced by Th1 cytokines. Alternative macrophage activation is induced by the Th2 cytokines interleukin (IL)-4 and IL-13; however, the role of adenosine in governing alternative macrophage activation is unknown. We show here that adenosine treatment of IL-4- or IL-13-activated macrophages augments the expression of alternative macrophage markers arginase-1, tissue inhibitor of matrix metalloproteinase-1 (TIMP-1), and macrophage galactose-type C-type lectin-1. The stimulatory effect of adenosine required primarily A(2B) receptors because the nonselective adenosine receptor agonist 5'-N-ethylcarboxamidoadenosine (NECA) increased both arginase activity (EC(50)=261.8 nM) and TIMP-1 production (EC(50)=80.67 nM), and both pharmacologic and genetic blockade of A(2B) receptors prevented the effect of NECA. A(2A) receptors also contributed to the adenosine augmentation of IL-4-induced TIMP-1 release, as both adenosine and NECA were less efficacious in augmenting TIMP-1 release by A(2A) receptor-deficient than control macrophages. Of the transcription factors known to drive alternative macrophage activation, CCAAT-enhancer-binding protein β was required, while cAMP response element-binding protein and signal transducer and activator of transcription 6 were dispensable in mediating the effect of adenosine. We propose that adenosine receptor activation suppresses inflammation and promotes tissue restitution, in part, by promoting alternative macrophage activation.
Collapse
Affiliation(s)
| | | | | | - Zoltán H. Németh
- Department of Surgery
- Department of Surgery, Morristown Memorial Hospital, Morristown, New Jersey, USA
| | - Pál Pacher
- National Institute on Alcohol Abuse and Alcoholism, Bethesda, Maryland, USA
| | - Peter J. Murray
- Department of Infectious Diseases and
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Diane Kepka-Lenhart
- Department of Microbiology and Molecular Genetics, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and
| | - Sidney M. Morris
- Department of Microbiology and Molecular Genetics, University of Pittsburgh, Pittsburgh, Pennsylvania, USA; and
| | | | - S. Joseph Leibovich
- Department of Cell Biology and Molecular Medicine, University of Medicine and Dentistry of New Jersey, New Jersey Medical School, Newark, New Jersey, USA
| | - György Haskó
- Department of Surgery
- Department of Medical Chemistry, Medical and Health Science Center, University of Debrecen, Debrecen, Hungary
| |
Collapse
|
13
|
Figler RA, Wang G, Srinivasan S, Jung DY, Zhang Z, Pankow JS, Ravid K, Fredholm B, Hedrick CC, Rich SS, Kim JK, LaNoue KF, Linden J. Links between insulin resistance, adenosine A2B receptors, and inflammatory markers in mice and humans. Diabetes 2011; 60:669-79. [PMID: 21270276 PMCID: PMC3028369 DOI: 10.2337/db10-1070] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To determine the mechanisms by which blockade of adenosine A(2B) receptors (A(2B)Rs) reduces insulin resistance. RESEARCH DESIGN AND METHODS We investigated the effects of deleting or blocking the A(2B)R on insulin sensitivity using glucose tolerance tests (GTTs) and hyperinsulinemic-euglycemic clamps in mouse models of type 2 diabetes. The effects of diabetes on A(2B)R transcription and signaling were measured in human and mouse macrophages and mouse endothelial cells. In addition, tag single nucleotide polymorphisms (SNPs) in ~42 kb encompassing the A(2B)R gene, ADORA2B, were evaluated for associations with markers of diabetes and inflammation. RESULTS Treatment of mice with the nonselective adenosine receptor agonist 5'-N-ethylcarboxamidoadensoine (NECA) increased fasting blood glucose and slowed glucose disposal during GTTs. These responses were inhibited by A(2B)R deletion or blockade and minimally affected by deletion of A(1)Rs or A(2A)Rs. During hyperinsulinemic-euglycemic clamp of diabetic KKA(Y) mice, A(2B)R antagonism increased glucose infusion rate, reduced hepatic glucose production, and increased glucose uptake into skeletal muscle and brown adipose tissue. Diabetes caused a four- to sixfold increase in A(2B)R mRNA in endothelial cells and macrophages and resulted in enhanced interleukin (IL)-6 production in response to NECA due to activation of protein kinases A and C. Five consecutive tag SNPs in ADORA2B were highly correlated with IL-6 and C-reactive protein (CRP). Diabetes had a highly significant independent effect on variation in inflammatory markers. The strength of associations between several ADORA2B SNPs and inflammatory markers was increased when accounting for diabetes status. CONCLUSIONS Diabetes affects the production of adenosine and the expression of A(2B)Rs that stimulate IL-6 and CRP production, insulin resistance, and the association between ADORA2B SNPs and inflammatory markers. We hypothesize that increased A(2B)R signaling in diabetes increases insulin resistance in part by elevating proinflammatory mediators. Selective A(2B)R blockers may be useful to treat insulin resistance.
Collapse
Affiliation(s)
- Robert A. Figler
- Cardiovascular Research Center, University of Virginia, Charlottesville, Virginia
| | - Guoquan Wang
- Adenosine Therapeutics Group of PGxHealth, Clinical Data Incorporated, Charlottesville, Virginia
| | - Susseela Srinivasan
- Cardiovascular Research Center, University of Virginia, Charlottesville, Virginia
| | - Dae Young Jung
- Department of Cellular and Molecular Physiology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Zhiyou Zhang
- Department of Cellular and Molecular Physiology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - James S. Pankow
- Department of Epidemiology and Community Health, University of Minnesota, Minneapolis, Minnesota
| | - Katya Ravid
- Department of Biochemistry, Boston University, Boston, Massachusetts
| | - Bertil Fredholm
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Catherine C. Hedrick
- Cardiovascular Research Center, University of Virginia, Charlottesville, Virginia
| | - Stephen S. Rich
- Center for Public Health Genomics, University of Virginia, Charlottesville, Virginia
| | - Jason K. Kim
- Department of Cellular and Molecular Physiology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Kathryn F. LaNoue
- Department of Biochemistry, Boston University, Boston, Massachusetts
| | - Joel Linden
- Cardiovascular Research Center, University of Virginia, Charlottesville, Virginia
- Corresponding author: Joel Linden,
| |
Collapse
|
14
|
Kovárů H, Kovaru F, Ondráčkova P, Lisá V, Fiserová A. Effect of fluoxetine or adenosine receptor NECA agonist on G-proteins of C6 glioma cells or NK immunocytes. Neuro Endocrinol Lett 2011; 32:274-278. [PMID: 21712787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 04/24/2011] [Accepted: 05/20/2011] [Indexed: 05/31/2023]
Abstract
OBJECTIVE Neurochemical approaches to antidepressant effects and depressive disorder are also focusing on G-protein coupled receptors (GPCR) and subsequent signalling. Trimeric G-proteins play a crucial role in transmembrane signalling, its amplification and processing. It is evident that immune system participates in antidepressant mode of action by neurotransmitter GPCR. METHODS We studied the effect of acute administration of fluoxetine or NECA agonist of adenosine receptor (GPCR) on C6 glioma cells and natural killer (NK) cell line, innate immunity. We used immunochemical estimation (ELISA) of the main types of G-protein alpha subunits from isolated membranes of tested cells. RESULTS Significant reduction of G alpha q/11 subunits after acute administration of fluoxetine or NECA agonist was found. In contrast, no significant influence of G alpha s or G alpha i1,2 subunit levels of C6 glioma cells were observed. Lowered Gq/11 signalling was in accordance with decreased 2nd messenger 1,4,5 IP3 formation by PLC. Acute effect of fluoxetine or NECA agonist on NK cell line resulted in significantly reduced G alpha q/11 levels without changes in G alpha s and G alpha i1,2. Furthermore, we determined that NECA agonist was able to abolish fluoxetine-evoked G alpha q/11 levels of NK cell line. CONCLUSIONS Results show involvement of fluoxetine in the C6 glioma signal transduction and were comparable with NK cells. Similar inhibiton of G alpha q/11 by NECA agonist in both C6 glioma cells and NK cell line was determined. Furthermore NECA induced attenuation of fluoxetine evoked Galpha q/11 signalling can indicate parallel interference between GPCR and final response. Finally, we determined similarity in both interleukin 2, IL2 immunostimulator and fluoxetine evoked G q/11 levels in NK cell line and thus fluoxetine action could be related to signalling aspects of neuroimmunomodulatory activity.
Collapse
Affiliation(s)
- Hana Kovárů
- 1st Faculty of Medicine, Charles University in Prague, Prague, Czech Republic.
| | | | | | | | | |
Collapse
|
15
|
Keene AM, Balasubramanian R, Lloyd J, Shainberg A, Jacobson KA. Multivalent dendrimeric and monomeric adenosine agonists attenuate cell death in HL-1 mouse cardiomyocytes expressing the A(3) receptor. Biochem Pharmacol 2010; 80:188-96. [PMID: 20346920 PMCID: PMC2880883 DOI: 10.1016/j.bcp.2010.03.020] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2010] [Revised: 03/15/2010] [Accepted: 03/16/2010] [Indexed: 11/15/2022]
Abstract
Multivalent dendrimeric conjugates of GPCR ligands may have increased potency or selectivity in comparison to monomeric ligands, a phenomenon that was tested in a model of cytoprotection in mouse HL-1 cardiomyocytes. Quantitative RT-PCR indicated high expression levels of endogenous A(1) and A(2A) adenosine receptors (ARs), but not of A(2B) and A(3)ARs. Activation of the heterologously expressed human A(3)AR in HL-1 cells by AR agonists significantly attenuated cell damage following 4h exposure to H(2)O(2) (750 microM) but not in untransfected cells. The A(3) agonist IB-MECA (EC(50) 3.8 microM) and the non-selective agonist NECA (EC(50) 3.9 microM) protected A(3) AR-transfected cells against H(2)O(2) in a concentration-dependent manner, as determined by lactate dehydrogenase release. A generation 5.5 PAMAM (polyamidoamine) dendrimeric conjugate of a N(6)-chain-functionalized adenosine agonist was synthesized and its mass indicated an average of 60 amide-linked nucleoside moieties out of 256 theoretical attachment sites. It non-selectively activated the A(3)AR to inhibit forskolin-stimulated cAMP formation (IC(50) 66nM) and, similarly, protected A(3)-transfected HL-1 cells from apoptosis-inducing H(2)O(2) with greater potency (IC(50) 35nM) than monomeric nucleosides. Thus, a PAMAM conjugate retained AR binding affinity and displayed greatly enhanced cardioprotective potency.
Collapse
Affiliation(s)
- Athena M. Keene
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-0810 USA
| | - Ramachandran Balasubramanian
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-0810 USA
| | - John Lloyd
- Mass Spectrometry Facility, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-0810 USA
| | - Asher Shainberg
- Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel
| | - Kenneth A. Jacobson
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-0810 USA
| |
Collapse
|
16
|
Yang D, Chen H, Koupenova M, Carroll SH, Eliades A, Freedman JE, Toselli P, Ravid K. A new role for the A2b adenosine receptor in regulating platelet function. J Thromb Haemost 2010; 8:817-27. [PMID: 20102488 DOI: 10.1111/j.1538-7836.2010.03769.x] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND Activation of platelets is a critical component of atherothrombosis and plays a central role in the progression of unstable cardiovascular syndromes. Adenosine, acting through adenosine receptors, increases intracellular cAMP levels and inhibits platelet aggregation. The A2a adenosine receptor has already been recognized as a mediator of adenosine-dependent effects on platelet aggregation, and here we present a new role for the A2b adenosine receptor (A2bAR) in this process. METHODS AND RESULTS As compared with platelets from wild-type controls, platelets derived from A2bAR knockout mice have significantly greater ADP receptor activation-induced aggregation. Although mouse megakaryocytes and platelets express low levels of the A2bAR transcript, this gene is highly upregulated following injury and systemic inflammation in vivo. Under these conditions, A2bAR-mediated inhibition of platelet aggregation significantly increases. Our studies also identify a novel mechanism by which the A2bAR could regulate platelet aggregation; namely, ablation of the A2bAR leads to upregulated expression of the P2Y1 ADP receptor, whereas A2bAR-mediated or direct elevation of cAMP has the opposite effect. Thus, the A2bAR regulates platelet function beyond mediating the immediate effect of adenosine on aggregation. CONCLUSIONS Taken together, these investigations show for the first time that the platelet A2bAR is upregulated under stress in vivo, plays a significant role in regulating ADP receptor expression, and inhibits agonist-induced platelet aggregation.
Collapse
MESH Headings
- Adenosine A2 Receptor Agonists
- Adenosine Diphosphate/blood
- Adenosine-5'-(N-ethylcarboxamide)/pharmacology
- Animals
- Blood Platelets/drug effects
- Blood Platelets/metabolism
- Cells, Cultured
- Cyclic AMP/blood
- Disease Models, Animal
- Femoral Artery/injuries
- Femoral Artery/metabolism
- Genotype
- Inflammation/chemically induced
- Inflammation/genetics
- Inflammation/metabolism
- Lipopolysaccharides
- Megakaryocytes/metabolism
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Phenotype
- Platelet Aggregation/drug effects
- Platelet Aggregation/genetics
- RNA, Messenger/blood
- Receptor, Adenosine A2B/blood
- Receptor, Adenosine A2B/deficiency
- Receptor, Adenosine A2B/genetics
- Receptors, Purinergic P2/blood
- Receptors, Purinergic P2/genetics
- Receptors, Purinergic P2Y1
- Time Factors
- Up-Regulation
Collapse
Affiliation(s)
- D Yang
- Department of Biochemistry, Boston University School of Medicine, Boston, MA 02118, USA
| | | | | | | | | | | | | | | |
Collapse
|
17
|
Tavares Gomes AL, Maia FB, Oliveira-Silva P, Marques Ventura AL, Paes-De-Carvalho R, Serfaty CA, Campello-Costa P. Purinergic modulation in the development of the rat uncrossed retinotectal pathway. Neuroscience 2009; 163:1061-8. [PMID: 19619617 DOI: 10.1016/j.neuroscience.2009.07.029] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2009] [Revised: 07/15/2009] [Accepted: 07/15/2009] [Indexed: 11/16/2022]
Abstract
Adenosine is a neuromodulator implicated in nervous system development and plasticity and its effects are mediated by inhibitory (A(1), A(3)) and excitatory (A(2a), A(2b)) receptors. The role of adenosine in the synaptic activity depends mainly on a balanced activation of A(1) and A(2a) receptors which are activated by various ranges of adenosine concentrations. Herein, we investigated the expression of A(1) and A(2a) receptors and also the accumulation of cAMP in the superior colliculus at different stages of development. Furthermore, we examined the effects of an acute in vivo blockade of adenosine deaminase during the critical period when the elimination of misplaced axons/terminals takes place with a simultaneous fine tuning of terminal arbors into appropriate terminal zones. Lister Hooded rats ranging from postnatal days (PND) 0-70 were used for ontogeny studies. Our results indicate that A(1) expression in the visual layers of the superior colliculus is higher until PND 28, while A(2a) expression increases after PND 28 in a complementary developmental pattern. Accordingly, the incubation of collicular slices with 5'-N-ethylcarboxamido-adenosine, a non-specific adenosine receptor agonist, showed a significant reduction in cAMP accumulation at PND 14 and an increase in adults. For the anatomical studies, the uncrossed retinotectal projections were traced after the intraocular injection of horseradish peroxidase. One group received daily injections of an adenosine deaminase inhibitor (erythro-9(2-hydroxy-3-nonyl adenine), 10 mg/kg i.p.) between PND 10 and 13, while control groups were treated with vehicle injections (NaCl 0.9%, i.p.). We found that a short-term blockade of adenosine deaminase during the second postnatal week induced an expansion of retinotectal terminal fields in the rostrocaudal axis of the tectum. Taken together, the results suggest that a balance of purinergic A(1) and A(2a) receptors through cAMP signaling plays a pivotal role during the development of topographic order in the retinotectal pathway.
Collapse
Affiliation(s)
- A L Tavares Gomes
- Programa de Neurociências, Departamento de Neurobiologia, Instituto de Biologia, Universidade Federal Fluminense, Niteroi, RJ, Brazil
| | | | | | | | | | | | | |
Collapse
|
18
|
Detoraki A, Staiano RI, Granata F, Giannattasio G, Prevete N, de Paulis A, Ribatti D, Genovese A, Triggiani M, Marone G. Vascular endothelial growth factors synthesized by human lung mast cells exert angiogenic effects. J Allergy Clin Immunol 2009; 123:1142-9, 1149.e1-5. [PMID: 19275959 DOI: 10.1016/j.jaci.2009.01.044] [Citation(s) in RCA: 150] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2008] [Revised: 01/13/2009] [Accepted: 01/14/2009] [Indexed: 11/19/2022]
Abstract
BACKGROUND Angiogenesis and lymphangiogenesis are critical for several allergic, inflammatory, and neoplastic disorders. Mast cells infiltrate the sites of inflammation and tumors. OBJECTIVE We sought to characterize the expression and functions of vascular endothelial growth factors (VEGFs) and their receptors (VEGFRs) in human mast cells. METHODS VEGF expression was evaluated by means of RT-PCR and Western blotting in primary human lung mast cells and in the mast cell lines LAD-2 and HMC-1. Angiogenic activity of mast cell supernatants was determined by using the chick embryo chorioallantoic membrane assay. VEGFR expression was assessed by means of RT-PCR and flow cytometry. Modified Boyden chambers were used for chemotaxis assay. RESULTS Human mast cells express VEGF-A, VEGF-B, VEGF-C, and VEGF-D at both the mRNA and protein level. Prostaglandin E(2) (PGE(2)) enhanced the expression of VEGFA, VEGFB, and VEGFC, whereas an adenosine analog (5'-[N-ethylcarboxamido] adenosine [NECA]) increased VEGFA, VEGFC, and VEGFD expression. In addition, PGE(2) and NECA enhanced VEGF-A release, and supernatants of PGE(2)- and NECA-activated human lung mast cells induced angiogenic responses in the chorioallantoic membrane assay that were inhibited by an anti-VEGF-A antibody. Mast cells expressed mRNA for VEGFR1 and VEGFR2. These receptors were present on the mast cell surface. VEGF-A(165), VEGF-B(167), VEGF-C, VEGF-D, and placental growth factor 1 induced mast cell chemotaxis. These chemotactic effects were mediated by the activation of both VEGFR-1 and VEGFR-2. CONCLUSION Our data indicate that human mast cells are both a source and a target of angiogenic and lymphangiogenic factors and therefore might play a role in inflammatory and neoplastic angiogenesis through the expression of several forms of VEGFs and their receptors.
Collapse
Affiliation(s)
- Aikaterini Detoraki
- Department of Clinical Immunology and Allergy, Center for Basic and Clinical Immunology Research (CISI), University of Naples Federico II, Naples, Italy
| | | | | | | | | | | | | | | | | | | |
Collapse
|
19
|
Hosseinzadeh H, Jaafari MR, Shamsara J. Selective inhibitory effect of adenosine A1 receptor agonists on the proliferation of human tumor cell lines. Iran Biomed J 2008; 12:203-208. [PMID: 19079533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
BACKGROUND In this study, the effects of three structural analogues of adenosine upon proliferation of human tumor cells were investigated. Previous research showed a cytotoxic effect of adenosine via A3 receptor and A1 receptor and sometimes this effect was receptor independent. The researches showed a differential cytotoxic effect of adenosine and its A3 agonists on cancerous cells, while other studies demonstrated tumor promoting effect of adenosine and its A1 agonists. The purpose of the present study was the evaluation of the possible selective anti-tumor effect of A1 receptor agonists on cancerous cells. METHODS The substances of N6-cyclohexyl-adenosine (CHA, A1 agonist), R-isomer of N6 phenylisopropyladenosine (R-PIA, A1 agonist) and N5-eethylcarboxamido-adenosine (NECA, adenosine A1-A2 non-specific agonist) were tested for their anti-proliferative effect using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay method. Hep G2, Hep2, CACO2, ACHN and L929 cell lines were used in this assay. RESULTS CHA inhibited cell proliferation in three cell lines (in concentration of 5-50 microM) and R-isomer of R-PIA in one cell line (in concentration of 10-50 microM). These effects were inhibited partially by addition of 1,3-Dipropyl-8-cyclopentylxanthine (A1 antagonist). The NECA analogue had no inhibitory effect on the cell proliferations. All of the substances had no cytotoxic effect on L929 cells (mouse connective tissue fibroblast cell line). CONCLUSION CHA and R-PIA had inhibitory effect on the proliferation of human tumor cell lines partially via A1 receptor, while they didn't show such effect on fibroblast cells. These results suggest that A1 adenosine receptor agonist have a good potential of specific anti-tumor activity.
Collapse
Affiliation(s)
- Hossein Hosseinzadeh
- Pharmaceutical Research Center, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Mahmoud R Jaafari
- Pharmaceutical Research Center, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
- Biotechnology Research Center, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Jamal Shamsara
- Pharmaceutical Research Center, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
| |
Collapse
|
20
|
Listos J, Talarek S, Fidecka S. Involvement of adenosine receptor agonists on the development of hypersensitivity to acute dose of morphine during morphine withdrawal period. Pharmacol Rep 2008; 60:679-685. [PMID: 19066414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2008] [Revised: 08/27/2008] [Indexed: 05/27/2023]
Abstract
In the present study, the involvement of the selective adenosine A1 (CPA) and A2A (CGS 21680) and non-selective adenosine A1/A2A (NECA) receptor agonists on the development of hypersensitivity to acute morphine injection given during opiate withdrawal was investigated. Intraperitioneal (ip) injections of morphine at increasing doses (10, 20, 30, 40, 50 mg/kg) for 6 consecutive days produced a state of dependence. On the 6th day, in the morning, animals were injected with the last dose of morphine (50 mg/kg, ip). Each day, 20 min before each injection of morphine, adenosine receptor agonists were also administered. Seven days after cessation of the morphine treatment, on the 13th day of the experiment, all animals were challenged with a dose of morphine (10 mg/kg, ip). A clear increase in locomotor activity was observed, indicating that hypersensitivity had developed. Our study has demonstrated the presence of an attenuating effect of adenosinergic drugs, such as CGS 21680 and NECA, but not CPA, on the development of hypersensitivity. The results indicate that stimulation of the adenosine A2A receptor plays some role in modulating the neuroadaptive changes appearing during chronic opioid treatment and that adenosine A2A receptor agonists may serve as useful drugs in relapse protection. Our investigations focused on adenosine A2A agonists as possible vehicles for pharmacotherapy for morphine addiction.
Collapse
Affiliation(s)
- Joanna Listos
- Department of Pharmacology and Pharmacodynamic, Medical University of Lublin, Staszica 4, PL 20-081 Lublin, Poland.
| | | | | |
Collapse
|
21
|
Brand F, Klutz AM, Jacobson KA, Fredholm BB, Schulte G. Adenosine A(2A) receptor dynamics studied with the novel fluorescent agonist Alexa488-APEC. Eur J Pharmacol 2008; 590:36-42. [PMID: 18603240 DOI: 10.1016/j.ejphar.2008.05.036] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2008] [Revised: 05/07/2008] [Accepted: 05/22/2008] [Indexed: 11/18/2022]
Abstract
G protein-coupled receptors, such as the adenosine A(2A) receptor, are dynamic proteins, which undergo agonist-dependent redistribution from the cell surface to intracellular membranous compartments, such as endosomes. In order to study the kinetics of adenosine A(2A) receptor redistribution in living cells, we synthesized a novel fluorescent agonist, Alexa488-APEC. Alexa488-APEC binds to adenosine A(2A) (K(i)=149+/-27 nM) as well as A(3) receptors (K(i)=240+/-160 nM) but not to adenosine A(1) receptors. Further, we characterized the dose-dependent increase in Alexa488-APEC-induced cAMP production as well as cAMP response element binding (CREB) protein phosphorylation, verifying the ligand's functionality at adenosine A(2A) but not A(2B) receptors. In live-cell imaging studies, Alexa488-APEC-induced adenosine A(2A) receptor internalization, which was blocked by the competitive reversible antagonist ZM 241385 and hyperosmolaric sucrose. Further, internalized adenosine A(2A) receptors co-localized with clathrin and Rab5, indicating that agonist stimulation promotes adenosine A(2A) receptor uptake through a clathrin-dependent mechanism to Rab5-positive endosomes. The basic characterization of Alexa488-APEC described here showed that it provides a useful tool for tracing adenosine A(2A) receptors in vitro.
Collapse
Affiliation(s)
- Frank Brand
- Karolinska Institutet, Department of Physiology & Pharmacology, Sect. Receptor Biology & Signaling, S-171 77 Stockholm, Sweden
| | | | | | | | | |
Collapse
|
22
|
Wei J, Yu WQ, Gao QZ. [Advances in the study of A2B adenosine receptor antagonists]. Yao Xue Xue Bao 2008; 43:241-246. [PMID: 18630258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
A2B adenosine receptor is involved in the control of mast cell degranulation, interleukin-8 synthesis and cell growth. A2B adenosine receptor antagonists may serve as novel drugs for asthma, Alzheimer' s disease, cystic fibrosis and type-II diabetes. Therefore, seeking for the highly selective A2B adenosine receptor antagonists has been one of great interest. The molecular basis, structure-activity relationship of selective A2B adenosine receptor antagonists and their interactions with A2B adenosine receptor were reviewed.
Collapse
Affiliation(s)
- Jing Wei
- School of Pharmaceutical Science and Technology, Tianjin University, Tianjin 300072, China
| | | | | |
Collapse
|
23
|
Sun WC, Moore JN, Hurley DJ, Vandenplas ML, Linden JM, Murray TF. Pharmacologic characterization of novel adenosine A2A receptor agonists in equine neutrophils. Am J Vet Res 2007; 68:981-7. [PMID: 17764413 DOI: 10.2460/ajvr.68.9.981] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To evaluate anti-inflammatory effects of several novel adenosine receptor agonists and to determine their specificity for various adenosine receptor subtypes on neutrophils, cells heterologously expressing equine adenosine receptors, or equine brain membranes. SAMPLE POPULATION Neutrophils isolated from 8 healthy horses. PROCEDURES Radioligand binding experiments were performed to compare binding affinities of adenosine receptor agonists to equine adenosine A(1), A(2A), and A(3) receptor subtypes. Effects of these agonists on endotoxin-induced production of reactive oxygen species (ROS) by equine neutrophils and roles of specific adenosine receptor subtypes and cAMP production in mediating these effects were determined. RESULTS Radioligand binding experiments yielded a ranked order of affinity for the brain equine A(2A) receptor on the basis of 50% inhibitory concentrations (IC(50)) of the agonists as follows: ATL307 (IC(50) = 1.9nM) and ATL313 > ATL309 and ATL310 > ATL202 > 2-([p-2- carboxyethyl] phenylethylamino)-5'-N-ethylcarboxyamidoadenosine > 5'-N-ethylcarboxamidoadenosine. Furthermore, ATL313 had approximately 100-fold greater selectivity for A(2A) over A(1) and A(3) receptors. In functional assays with equine neutrophils, the compounds inhibited endotoxin-induced ROS production and stimulated production of cAMP with the same ranked order of potency. Results of experiments performed with selective adenosine receptor antagonists indicated that functional effects of ATL313 were via stimulation of A(2A) receptors. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that activation of A(2A) receptors exerted anti-inflammatory effects on equine neutrophils and that stable, highly selective adenosine A(2A) receptor agonists may be developed for use in management of horses and other domestic animals with septic and nonseptic inflammatory diseases.
Collapse
Affiliation(s)
- Wan-chun Sun
- Department of Large Animal Medicine, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA
| | | | | | | | | | | |
Collapse
|
24
|
Wiktorowska-Owczarek A, Namiecinska M, Balcerczyk A, Nowak JZ. Human micro- and macrovessel-derived endothelial cells: a comparative study on the effects of adrenaline and a selective adenosine A2-type receptor agonist under normoxic and hypoxic conditions. Pharmacol Rep 2007; 59:800-806. [PMID: 18195474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2007] [Revised: 12/06/2007] [Indexed: 05/25/2023]
Abstract
Adrenaline is a highly effective stimulator of cyclic AMP (cAMP) production in microvascular endothelial cells (ECs)--HMEC-1, showing only a moderate activity in macrovascular ECs--HUVEC. In both EC preparations, adrenaline acts via beta-type receptors. Selective stimulation of adenosine A(2)-type receptors resulted in comparable increases in cAMP formation in ECs lining micro- and macrovessels. Hypoxia largely suppressed the cAMP effects resulting from stimulation of both beta-adrenoceptors and adenosine A(2) type receptors in ECs of microvessels (HMEC-1). In contrast, hypoxia had only slight effect on these responses in ECs of macrovessels (HUVEC). The present data provide further evidence of functional differences between microvessel- and macrovessel-derived ECs.
Collapse
|
25
|
Sun WC, Moore JN, Hurley DJ, Vandenplas ML, Linden J, Cao Z, Murray TF. Adenosine A2A receptor agonists inhibit lipopolysaccharide-induced production of tumor necrosis factor-alpha by equine monocytes. Vet Immunol Immunopathol 2007; 121:91-100. [PMID: 17913243 DOI: 10.1016/j.vetimm.2007.08.011] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2007] [Revised: 08/15/2007] [Accepted: 08/20/2007] [Indexed: 11/16/2022]
Abstract
Adenosine is an endogenous nucleoside that regulates many physiological processes by activating one or more adenosine receptor subtypes, namely A1, A2A, A2B and A3. The results of previous studies indicate that adenosine analogues inhibit lipopolysaccharide (LPS)-induced production of reactive oxygen species (ROS) by equine neutrophils primarily through activation of A2A receptors. Because peripheral blood monocytes produce cytokines that are responsible for many of the deleterious effects of LPS, the current study was performed to evaluate the effects of an array of novel adenosine receptor agonists on LPS-induced production of tumor necrosis factor-alpha (TNF-alpha), and to assess the selectively of these agonists for equine adenosine A2A over the A1 receptor. Radioligand binding studies performed with equine tissues expressing adenosine A1 and A2A receptor subtypes yielded a rank order of affinity for the equine A2A receptor of ATL307>ATL309 approximately ATL310 approximately ATL313>ATL202 approximately ATL361 approximately ATL376>ATL372>CGS21680>NECA. Co-incubation of equine peripheral blood monocytes with LPS and these agonists resulted in inhibition of TNF-alpha production with a rank order of potency that strongly correlated with their binding affinities for equine adenosine A2A receptors. Results of experiments performed with one of the adenosine receptor agonists (ATL313) and selective adenosine receptor antagonists confirmed that inhibition of LPS-induced production of TNF-alpha occurred via stimulation of A2A receptors. Although incubation of monocytes with IB-MECA, a compound purported to act as an adenosine A3 receptor agonist, reduced LPS-induced TNF-alpha production, this effect of IB-MECA was inhibited by the A2A selective antagonist ZM241385 but not by the A3 receptor antagonist MRS1220. These results indicate that the adenosine receptor subtype responsible for regulation of LPS-induced cytokine production by equine monocytes is the A2A receptor. To address the signal transduction mechanism responsible for the anti-inflammatory effects of ATL313 in equine monocytes, production of cAMP was compared in the presence and absence of either the adenosine A2A receptor antagonist ZM241385 or the adenosine A2B receptor antagonist MRS1706. In the absence of the antagonists, ATL313 increased production of cAMP; ZM241385 inhibited this effect of ATL313, whereas MRS1706 did not. Furthermore, incubation of monocytes with either the stable analogue of cAMP, dibutyryl cAMP, or forskolin, an activator of adenylyl cyclase, also inhibited LPS-induced production of TNF-alpha production by equine monocytes. Collectively, the results of the current study indicate that adenosine analogues inhibit LPS-induced production of TNF-alpha by equine monocytes primarily via activation of adenosine A2A receptors and do so in a cAMP-dependent manner. The results of this study indicate that stable adenosine analogues that are selective for adenosine A2A receptors may be suitable for development as anti-inflammatory drugs in horses.
Collapse
Affiliation(s)
- Wan-Chun Sun
- Department of Large Animal Medicine, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, United States
| | | | | | | | | | | | | |
Collapse
|
26
|
Sun WC, Moore JN, Hurley DJ, Vandenplas ML, Murray TF. Effects of stimulation of adenosine A2A receptors on lipopolysaccharide-induced production of reactive oxygen species by equine neutrophils. Am J Vet Res 2007; 68:649-56. [PMID: 17542699 DOI: 10.2460/ajvr.68.6.649] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To assess the anti-inflammatory effects of an adenosine analogue on lipopolysaccharide (LPS)-stimulated equine neutrophils. SAMPLE POPULATION Neutrophils obtained from 10 healthy horses. PROCEDURES An adenosine analogue (5'-N-ethylcarboxamidoadenosine [NECA]) was tested for its ability to inhibit production of reactive oxygen species (ROS) in LPS-stimulated equine neutrophils. Selective adenosine receptor antagonists were used to identify the receptor subtype responsible for effects. To assess the mechanism of action of NECA, cAMP concentrations were measured, and effects of dibutyryl cAMP (a stable analogue of cAMP) and rolipram (a type 4 phosphodiesterase inhibitor) were investigated. RESULTS NECA elicited concentration-dependent inhibition of ROS production that was inhibited by ZM241385, a selective adenosine A(2A) receptor antagonist; this effect of NECA was not affected by the adenosine A(2B) receptor antagonist MRS1706. Also, ZM241385 blocked NECA-induced increases in cAMP concentrations, whereas MRS1706 did not alter this effect of NECA. Rolipram potentiated NECA-induced inhibition of ROS production, and dibutyryl cAMP also inhibited ROS production. CONCLUSIONS AND CLINICAL RELEVANCE Activation of adenosine A(2A) receptors inhibited ROS production by LPS-stimulated equine neutrophils in a cAMP-dependent manner. These results suggest that stable adenosine A(2A) receptor agonists may be developed as suitable anti-inflammatory drugs in horses.
Collapse
Affiliation(s)
- Wan-chun Sun
- Department of Large Animal Medicine, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA
| | | | | | | | | |
Collapse
|
27
|
Pierson PM, Peteri-Brunbäck B, Pisani DF, Abbracchio MP, Mienville JM, Rosso L. A(2b) receptor mediates adenosine inhibition of taurine efflux from pituicytes. Biol Cell 2007; 99:445-54. [PMID: 17391106 DOI: 10.1042/bc20070028] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND INFORMATION Recent work suggests that part of the control of vasopressin output is mediated by taurine released from pituicytes, the astroglial cells of the neurohypophysis. Taurine release, in turn, is stimulated by hypotonic conditions and by vasopressin itself. As adenosine is generated from ATP co-released with vasopressin, it appeared important to study its effects on taurine efflux from pituicytes. RESULTS We measured radioactive efflux from cultured pituicytes and whole neurohypophyses pre-loaded with [(3)H]taurine. Cultured pituicytes were also used to study adenosine-receptor mRNA expression. Taurine efflux elicited by hypotonic shocks is approximately 30-50% smaller in the presence of 10 microM adenosine or 1 microM NECA (5'-N-ethylcarboxamidoadenosine). Both compounds also inhibited basal efflux in a manner that was not immediately reversible. Agonists of the adenosine A1-, A2a- or A3-receptor subtypes have no relevant effect on basal taurine release, and the A1-receptor antagonist DPCPX (8-cyclopentyl-1,3-dipropylxanthine) has no effect on the inhibition of release by NECA. In turn, the A2b-receptor antagonists MRS 1706 {N-(4-acetylphenyl)-2-[4-(2,3,6,7-tetrahydro-2,6-dioxo-1,3-dipropyl-1H-purin-8-yl)phenoxy]acetamide} or alloxazine partially reverse the inhibition of basal or hypotonicity-evoked efflux by NECA. Both A1- and A2b-receptor mRNAs are expressed in pituicytes, which is consistent with an A1-receptor-mediated effect on cell morphology and an A2b-receptor-mediated effect on taurine release. Forskolin and dibutyryl cAMP mimic the inhibitory effects of purinergics on basal taurine efflux, and the adenylate cyclase inhibitor DDA (2',5'-dideoxyadenosine) partially reverses the inhibition of the hypotonic response by NECA.Conclusions. Our results suggest that purinergic inhibition of taurine efflux from pituicytes operates through A2b receptors coupled to intracellular cAMP increase. They point to a possible modulation of neurohypophysial hormone output by endogenous adenosine released in either physiological or pathological situations.
Collapse
Affiliation(s)
- Patricia M Pierson
- CNRS UMR 6548, Laboratoire de Physiologie Cellulaire et Moléculaire, Université de Nice-Sophia Antipolis, Nice, France
| | | | | | | | | | | |
Collapse
|
28
|
Abstract
Adenosine and adenosine receptor antagonists are involved in glucose homoeostasis. The participating receptors are not known, mainly due to a lack of specific agonists and antagonists, but are reasonable targets for anti-diabetic therapy. The stable, albeit nonselective, adenosine analogue NECA (5'-N-ethylcarboxamidoadenosine) (10 microM) reduced glucose-stimulated insulin release from INS-1 cells. This was mimicked by A(1)-(CHA), A(2A)-(CGS-21680) and A(3)-receptor agonists (Cl-IB-MECA). Two newly synthesized A(2B)-receptor antagonists, PSB-53 and PSB-1115, counteracted the inhibitory effect of NECA. These in-vitro effects were mirrored by in-vivo data with respect to CHA, CGS and Cl-IB-MECA. Distinct concentrations of either PSB-53 or PSB-1115 reversed the decrease in plasma insulin induced by NECA. This was not mimicked by a corresponding change in blood glucose. The effect of PSB-1115 was also obvious in diabetic GotoKakizaki rats: plasma insulin was increased whereas blood glucose was unchanged. During most experiments the effects on blood glucose were not impressive probably because of the physiologically necessary homoeostasis. The adenosine levels were not different in normal Wistar rats and in diabetic GotoKakzaki rats. Altogether the A(2B)-receptor antagonists showed an anti-diabetic potential mainly by increasing plasma insulin levels under conditions when the adenosine tonus was elevated in-vivo and increased insulin release in-vitro.
Collapse
Affiliation(s)
- D Rüsing
- Department of Pharmacology, Institute of Pharmaceutical and Medicinal Chemistry, University of Muenster, Germany
| | | | | |
Collapse
|
29
|
Morikawa T, Tanaka N, Kubota Y, Mizuno H, Nakamura K, Kunitomo M, Shinozuka K. ATP modulates the release of noradrenaline through two different prejunctional receptors on the adrenergic nerves of rat prostate. Clin Exp Pharmacol Physiol 2007; 34:601-5. [PMID: 17581215 DOI: 10.1111/j.1440-1681.2007.04627.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
1. The effects of adenosine and ATP receptor agonists on the release of endogenous noradrenaline from electrically stimulated (2 Hz, 0.1 msec) rat prostate were examined in order to clarify the pharmacological properties of prejunctional receptors for adenosine and ATP on the adrenergic nerve varicosities in the prostate. Noradrenaline was quantified by HPLC coupled with electrochemical detection techniques. 2. Both adenosine and ATP receptor agonists (1 micromol/L) inhibited noradrenaline release and the relative order of inhibitory effect was N(6)-cyclopentyl-adenosine (CPA) > 5'-N-ethylcarboxamidoadenosine > 2-chloroadenosine > adenosine > 2-methylthio-ATP (2mSATP) > AMP > ATP. 3. The adenosine receptor agonist CPA (1 nmol/L-1 micromol/L) and the ATP receptor agonist 2mSATP (100 nmol/L-100 micromol/L) inhibited the stimulation-induced release of noradrenaline in a concentration-dependent manner. The concentrations of CPA and 2mSATP that produced 50% inhibition of noradrenaline release were 9.6 nmol/L and 1.4 micromol/L, respectively. 4. 1,3-Dipropyl-8-cyclopentylxanthine, an adenosine A(1) receptor antagonist, significantly reduced the inhibitory effects of not only CPA, but also 2mSATP. 5. Suramin, an ATP receptor antagonist, significantly reduced the inhibitory effects of 2mSATP, but not those of CPA. 6. Pyridoxalphosphate-6-azophenyl-2',4'-disulphonic acid, another ATP receptor antagonist, had no effect on the inhibitory action of either agonist. 7. These results suggest that, in the sympathetic nerve terminals of rat prostate, adenosine and ATP induce inhibition of noradrenaline release via the activation of adenosine A(1) and/or xanthine-sensitive ATP receptors, which play an inhibitory regulatory role in adrenergic neurotransmission in the prostate.
Collapse
Affiliation(s)
- Tsugumi Morikawa
- Department of Pharmacology, School of Pharmaceutical Sciences, Mukogawa Women's University, Nishinomiya, Japan
| | | | | | | | | | | | | |
Collapse
|
30
|
Breschi MC, Blandizzi C, Fogli S, Martinelli C, Adinolfi B, Calderone V, Camici M, Martinotti E, Nieri P. In vivo adenosine A(2B) receptor desensitization in guinea-pig airway smooth muscle: implications for asthma. Eur J Pharmacol 2007; 575:149-57. [PMID: 17716655 DOI: 10.1016/j.ejphar.2007.07.051] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2007] [Revised: 06/28/2007] [Accepted: 07/17/2007] [Indexed: 11/17/2022]
Abstract
This study was aimed at characterizing the role of adenosine receptor subtypes in the contractility modulation of guinea-pig airway smooth muscle in normal and pathological settings. In vitro and in vivo experiments were performed by testing selective agonists and antagonists on isolated tracheal smooth muscle preparations and pulmonary inflation pressure, respectively, under normal conditions or following ovalbumin-induced allergic sensitization. In normal and sensitized animals, the adenosine A(2A)/A(2B) receptor agonist, NECA, evoked relaxing responses of isolated tracheal preparations precontracted with histamine, and such an effect was reversed by the adenosine A(2B) antagonist, MRS 1706, in the presence or in the absence of epithelium. The expression of mRNA coding for adenosine A(2B) receptors was demonstrated in tracheal specimens. In vitro desensitization with 100 microM NECA markedly reduced the relaxing effect of the agonist. In vivo NECA or adenosine administration to normal animals inhibited histamine-mediated bronchoconstriction, while these inhibitory effects no longer occurred in sensitized guinea-pigs. Adenosine plasma levels were significantly higher in sensitized than normal animals. In conclusion, our data demonstrate that: (i) adenosine A(2B) receptors are responsible for the relaxing effects of adenosine on guinea-pig airways; (ii) these receptors can undergo rapid adaptive changes that may affect airway smooth muscle responsiveness to adenosine; (iii) ovalbumin-induced sensitization promotes a reversible inactivation of adenosine A(2B) receptors which can be ascribed to homologous desensitization. These findings can be relevant to better understand adenosine functions in airways as well as mechanisms of action of asthma therapies targeting the adenosine system.
Collapse
Affiliation(s)
- Maria Cristina Breschi
- Department of Psychiatry, Neurobiology, Pharmacology and Biotechnology, University of Pisa, Via Bonanno 6, I-56126, Pisa, Italy.
| | | | | | | | | | | | | | | | | |
Collapse
|
31
|
Kang MJ, Koh HC. Involvement of guanylate cyclase in the cardiovascular response induced by adenosine A2B receptor stimulation in the posterior hypothalamus of the anesthetized rats. Auton Neurosci 2007; 134:55-60. [PMID: 17363336 DOI: 10.1016/j.autneu.2007.02.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2006] [Revised: 01/31/2007] [Accepted: 02/11/2007] [Indexed: 11/29/2022]
Abstract
Cardiovascular inhibitory effects induced by the posterior hypothalamic adenosine A(2) receptors were suggested by our previous reports. In this experiment, we examined the influence of the posterior hypothalamic adenosine A(2B) receptors on central cardiovascular regulation of blood pressure (BP) and heart rate (HR). Posterior hypothalamic injection of drugs was performed in anesthetized, artificially ventilated male Sprague-Dawley rats. Injection of 5'-(N-cyclopropyl)-carboxamidoadenosine (CPCA; 2 nmol), an adenosine A(2) receptor agonist, showed the decrease of arterial blood pressure and heart rate, and the alloxazine, an adenosine A(2B) receptor antagonist, partially blocked the depressor and bradycardiac effects of CPCA (2 nmol). To examine the role of adenosine A(2B) receptors among the adenosine A(2) subtypes, we applied the 5'-N-Ethylcarboxamidoadenosine (NECA), an adenosine A(2B) receptor agonist, to the posterior hypothalamus. Injection of NECA (1, 4 and 8 nmol) produced a dose-dependent decrease of arterial blood pressure and HR. Pretreatment with alloxazine (5 nmol) partially blocked the depressor and bradycardiac effects of NECA (4 nmol). Also, pretreatment with LY-83,583 (5 nmol), a soluble guanylate cyclase inhibitor, attenuated the depressor and bradycardiac effects of NECA (4 nmol). However, pretreatment with MDL-12,330 (10 nmol), an adenylate cyclase inhibitor, did not affect these effects of NECA (4 nmol). These results suggest that adenosine A(2B) receptor in the posterior hypothalamus plays an inhibitory role in central cardiovascular regulation, and that guanylate cyclase mediates the depressor and bradycardiac actions of adenosine A(2B) receptors.
Collapse
Affiliation(s)
- Min Jeong Kang
- Department of Pharmacology, College of Medicine, Hanyang University, 17 Haengdang-Dong, Sungdong-Ku, Seoul 133-791, Republic of Korea
| | | |
Collapse
|
32
|
Haschemi A, Wagner O, Marculescu R, Wegiel B, Robson SC, Gagliani N, Gallo D, Chen JF, Bach FH, Otterbein LE. Cross-regulation of carbon monoxide and the adenosine A2a receptor in macrophages. J Immunol 2007; 178:5921-9. [PMID: 17442976 DOI: 10.4049/jimmunol.178.9.5921] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Adenosine and heme oxygenase-1 (HO-1) exert a wide range of anti-inflammatory and immunomodulatory actions, making them crucial regulatory molecules. Despite the diversity in their modes of action, the similarity of biological effects of adenosine and HO-1 led us to hypothesize a possible interrelationship between them. We assessed a potential role for HO-1 in the ability of adenosine or 5'-N-ethylcarboxamidoadenosine (NECA), a stable adenosine analog, to modify the response of LPS-stimulated macrophages. Adenosine and NECA markedly induced HO-1 and blocked LPS-induced TNF-alpha production via adenosine A2aR-mediated signaling; blocking of HO-1 by RNA interference abrogated the effects of adenosine and NECA on TNF-alpha. HO-1 overexpression or exposure to carbon monoxide (CO), a product of HO-1 enzymatic activity, resulted in augmented A2aR mRNA and protein levels in RAW264.7 cells and primary macrophages. The induction of A2aR expression by HO-1 or CO resulted in an increase in the sensitivity to the anti-inflammatory effects of adenosine and NECA, which was lost in macrophages isolated from A2aR-deficient mice. Moreover, a decrease in cAMP levels upon NECA stimulation of naive macrophages was counterbalanced by CO exposure to up-regulate A2aR levels. This implies adenosine receptor isoform switch as a selective modification in macrophage phenotype. Taken together, these data suggest the existence of a positive feedback loop among adenosine, HO-1, CO, and the A2aR in the chronological resolution of the inflammatory response.
Collapse
Affiliation(s)
- Arvand Haschemi
- Transplant and Immunobiology Research Centers, Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, 99 Brookline Avenue, Boston, MA 02215, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
33
|
Kuno A, Critz SD, Cui L, Solodushko V, Yang XM, Krahn T, Albrecht B, Philipp S, Cohen MV, Downey JM. Protein kinase C protects preconditioned rabbit hearts by increasing sensitivity of adenosine A2b-dependent signaling during early reperfusion. J Mol Cell Cardiol 2007; 43:262-71. [PMID: 17632123 PMCID: PMC2729547 DOI: 10.1016/j.yjmcc.2007.05.016] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2006] [Revised: 05/11/2007] [Accepted: 05/15/2007] [Indexed: 11/28/2022]
Abstract
Although protein kinase C (PKC) plays a key role in ischemic preconditioning (IPC), the actual mechanism of that protection is unknown. We recently found that protection from IPC requires activation of adenosine receptors during early reperfusion. We, therefore, hypothesized that PKC might act to increase the heart's sensitivity to adenosine. IPC limited infarct size in isolated rabbit hearts subjected to 30-min regional ischemia/2-h reperfusion and IPC's protection was blocked by the PKC inhibitor chelerythrine given during early reperfusion revealing involvement of PKC at reperfusion. Similarly chelerythrine infused in the early reperfusion period blocked the increased phosphorylation of the protective kinases Akt and ERK1/2 observed after IPC. Infusing phorbol 12-myristate 13-acetate (PMA), a PKC activator, during early reperfusion mimicked IPC's protection. As expected, the protection triggered by PMA at reperfusion was blocked by chelerythrine, but surprisingly it was also blocked by MRS1754, an adenosine A(2b) receptor-selective antagonist, suggesting that PKC was somehow facilitating signaling from the A(2b) receptors. NECA [5'-(N-ethylcarboxamido) adenosine], a potent but not selective A(2b) receptor agonist, increased phosphorylation of Akt and ERK1/2 in a dose-dependent manner. Pretreating hearts with PMA or brief preconditioning ischemia had no effect on phosphorylation of Akt or ERK1/2 per se but markedly lowered the threshold for NECA to induce their phosphorylation. BAY 60-6583, a highly selective A(2b) agonist, also caused phosphorylation of ERK1/2 and Akt. MRS1754 prevented phosphorylation induced by BAY 60-6583. BAY 60-6583 limited infarct size when given to ischemic hearts at reperfusion. These results suggest that activation of cardiac A(2b) receptors at reperfusion is protective, but because of the very low affinity of the receptors endogenous cardiac adenosine is unable to trigger their signaling. We propose that the key protective event in IPC occurs when PKC increases the heart's sensitivity to adenosine so that endogenous adenosine can activate A(2b)-dependent signaling.
Collapse
Affiliation(s)
- Atsushi Kuno
- Department of Physiology, University of South Alabama, College of Medicine, Mobile, AL
| | - Stuart D. Critz
- Department of Cell Biology and Neuroscience, University of South Alabama, College of Medicine, Mobile, AL
| | - Lin Cui
- Department of Physiology, University of South Alabama, College of Medicine, Mobile, AL
| | - Victoriya Solodushko
- Department of Physiology, University of South Alabama, College of Medicine, Mobile, AL
| | - Xi-Ming Yang
- Department of Physiology, University of South Alabama, College of Medicine, Mobile, AL
| | | | | | - Sebastian Philipp
- Department of Physiology, University of South Alabama, College of Medicine, Mobile, AL
| | - Michael V. Cohen
- Department of Physiology, University of South Alabama, College of Medicine, Mobile, AL
- Department of Medicine, University of South Alabama, College of Medicine, Mobile, AL
| | - James M. Downey
- Department of Physiology, University of South Alabama, College of Medicine, Mobile, AL
| |
Collapse
|
34
|
D'hondt C, Srinivas SP, Vereecke J, Himpens B. Adenosine opposes thrombin-induced inhibition of intercellular calcium wave in corneal endothelial cells. Invest Ophthalmol Vis Sci 2007; 48:1518-27. [PMID: 17389480 DOI: 10.1167/iovs.06-1062] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE In corneal endothelial cells, intercellular Ca(2+) waves elicited by a mechanical stimulus involve paracrine intercellular communication, mediated by ATP release via connexin hemichannels, as well as gap junctional intercellular communication. Both mechanisms are inhibited by thrombin, which activates RhoA and hence results in myosin light chain phosphorylation. This study was conducted to examine the effects of adenosine, which is known to oppose thrombin-induced RhoA activation, thereby leading to myosin light chain dephosphorylation, on gap junctional intercellular communication and paracrine intercellular communication in cultured bovine corneal endothelial cells. METHODS An intercellular Ca(2+) wave was elicited by applying a mechanical stimulus to a single cell in a confluent monolayer. The area of Ca(2+) wave propagation was measured by [Ca(2+)](i) imaging using the fluorescent dye Fluo-4. Gap junctional intercellular communication was assessed by fluorescence recovery after photobleaching. Activity of hemichannels was determined by uptake of the hydrophilic dye Lucifer yellow in a Ca(2+)-free medium containing 2 mM EGTA. Adenosine triphosphate (ATP) release in response to mechanical stimulation was measured using the luciferin-luciferase technique. Gap26, a connexin mimetic peptide, was used to block hemichannels. RESULTS Exposure to thrombin or TRAP-6 (a selective PAR-1 agonist) inhibited the Ca(2+) wave propagation by 70%. Pretreatment with adenosine prevented this inhibitory effect of thrombin. NECA (a potent A2B agonist) and forskolin, agents known to elevate cAMP in bovine corneal endothelial cells, also suppressed the effect of thrombin. The A1 receptor agonist CPA failed to inhibit the effect of thrombin. Similar to the effects on Ca(2+) wave propagation, adenosine prevented the thrombin-induced reduction in the fluorescence recovery during photobleaching experiments. Furthermore, pretreatment with adenosine prevented both thrombin and TRAP-6 from blocking the uptake of Lucifer yellow in a Ca(2+)-free medium. However, adenosine was ineffective in overcoming the Gap26-mediated block of Lucifer yellow uptake. In consistence with Lucifer yellow uptake through hemichannels, the thrombin-induced inhibition of ATP release was overcome by pretreatment with adenosine. CONCLUSIONS Adenosine prevents thrombin-induced inhibition of hemichannel-mediated paracrine intercellular communication and of gap junctional intercellular communication. The mechanism involves an increase in cAMP, which results in inhibition of RhoA and a subsequent decrease in myosin light chain phosphorylation. Since myosin light chain dephosphorylation causes a decrease in contractility of the actin cytoskeleton, the results suggest possible effects of the actin cytoskeleton on gap junctions and connexin hemichannels.
Collapse
Affiliation(s)
- Catheleyne D'hondt
- Laboratory of Physiology, KU Leuven (Katholieke Universiteit Leuven), Campus Gasthuisberg O/N, B-3000 Leuven, Belgium
| | | | | | | |
Collapse
|
35
|
Hermansson NO, Morgan DGA, Drmota T, Larsson N. Adenosine is not a direct GHSR agonist--artificial cross-talk between GHSR and adenosine receptor pathways. Acta Physiol (Oxf) 2007; 190:77-86. [PMID: 17428235 DOI: 10.1111/j.1365-201x.2007.01691.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
AIM To assess if adenosine is a direct growth hormone secretagogue receptor (GHSR) agonist by investigating the mechanism behind adenosine induced calcium release in human embryonic kidney 293s (HEK) cells expressing GHSR. METHODS Calcium mobilization, cyclic adenosine monophosphate (cAMP) and IP(3) experiments were performed using HEK cells stably expressing GHSR and/or adenosine A(2B) receptor (A(2B)R). RESULTS Adenosine has been widely reported as a GHSR agonist. In our hands, adenosine and forskolin stimulated calcium release from IP(3) controlled stores in HEK-GHSR cells but not in non-transfected HEK cells. This release was not accompanied by increased IP(3) levels. The calcium release was both cholera toxin and U73122 sensitive, indicating the involvement of both Galpha(s)/adenylyl cyclase and Galpha(q/11)/phospholipase C pathways. Importantly, the GHSR inverse agonist [D-Arg(1) D-Phe(5) D-Trp(7,9) Leu(11)]-Substance P (SP-analogue) blocked the adenosine stimulated calcium release, demonstrating that GHSR is involved. Assessment of the GHSR-dependent calcium release using adenosine receptor agonists and antagonists resulted in a rank order of potencies resembling the profile of A(2B)R. A(2B)R over-expression in HEK-GHSR cells enhanced potency and efficacy of the adenosine induced calcium release without increasing IP(3) production. Moreover, A(2B)R over-expression in HEK cells potentiated NECA-induced cAMP production. However, GHSR expression had no effect on intracellular cAMP production. CONCLUSION In HEK-GHSR cells adenosine activates endogenously expressed A(2B)R resulting in calcium mobilization. We hypothesize that the responsible mechanism is cAMP-dependent sensitization of IP(3) receptors for the high basal level of IP(3) caused by GHSR constitutive activity. Altogether, our results demonstrate that adenosine is not a direct GHSR agonist.
Collapse
Affiliation(s)
- N-O Hermansson
- Department of Lead Generation, AstraZeneca R&D Mölndal, Mölndal, Sweden
| | | | | | | |
Collapse
|
36
|
Hua X, Erikson CJ, Chason KD, Rosebrock CN, Deshpande DA, Penn RB, Tilley SL. Involvement of A1 adenosine receptors and neural pathways in adenosine-induced bronchoconstriction in mice. Am J Physiol Lung Cell Mol Physiol 2007; 293:L25-32. [PMID: 17468137 DOI: 10.1152/ajplung.00058.2007] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
High levels of adenosine can be measured from the lungs of asthmatics, and it is well recognized that aerosolized 5'AMP, the precursor of adenosine, elicits robust bronchoconstriction in patients with this disease. Characterization of mice with elevated adenosine levels secondary to the loss of adenosine deaminase (ADA) expression, the primary metabolic enzyme for adenosine, further support a role for this ubiquitous mediator in the pathogenesis of asthma. To begin to identify pathways by which adenosine can alter airway tone, we examined adenosine-induced bronchoconstriction in four mouse lines, each lacking one of the receptors for this nucleoside. We show, using direct measures of airway mechanics, that adenosine can increase airway resistance and that this increase in resistance is mediated by binding the A(1) receptor. Further examination of this response using pharmacologically, surgically, and genetically manipulated mice supports a model in which adenosine-induced bronchoconstriction occurs indirectly through the activation of sensory neurons.
Collapse
Affiliation(s)
- Xiaoyang Hua
- Department of Medicine, Division of Pulmonary and Critical Care Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-7219, USA
| | | | | | | | | | | | | |
Collapse
|
37
|
Zhu CB, Steiner JA, Munn JL, Daws LC, Hewlett WA, Blakely RD. Rapid stimulation of presynaptic serotonin transport by A(3) adenosine receptors. J Pharmacol Exp Ther 2007; 322:332-40. [PMID: 17460150 DOI: 10.1124/jpet.107.121665] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The inactivation of synaptic serotonin (5-hydroxytryptamine, 5-HT) is largely established through the actions of the presynaptic, antidepressant-sensitive 5-HT transporter (SERT, SLC6A4). Recent studies have demonstrated post-translational regulation of SERT mediated by multiple Ser/Thr kinases, including protein kinases C and G (PKC and PKG) and p38 mitogen-activated protein kinase (MAPK), as well as the Ser/Thr phosphatase PP2A. Less well studied are specific surface receptors that target these signaling pathways to control SERT surface expression and/or catalytic rates. Using rat basophilic leukemia 2H3 cell line (RBL-2H3), we previously established that activation of A(3) adenosine receptors (A(3)AR) stimulates SERT activity via both PKG and p38 MAPK (Zhu et al., 2004a). Whether A(3)ARs regulate SERT in the central nervous system (CNS) is unknown. Here we report that the A(3)AR agonist N(6)-(3-iodobenzyl)-N-methyl-5'carbamoyladenosine (IB-MECA) rapidly (10 min) and selectively stimulates 5-HT transport in mouse midbrain, hippocampal, and cortical synaptosomes. IB-MECA-induced stimulation of 5-HT uptake is blocked by the selective A(3)AR antagonist 3-ethyl-5-benzyl-2-methyl-phenylethynyl-6-phenyl-1,4(+/-)dihydropyridine-3,5-dicarboxylate (MRS1191) and is absent from synaptosomes prepared from A(3)AR knockout mice. Kinetic analyses demonstrate that IB-MECA induces an increase of 5-HT transport V(max) with no significant change in K(m). As in RBL-2H3 cells, IB-MECA stimulation of synaptosomal 5-HT uptake can be blocked by preincubation with PKG antagonists N-[2-(methylamino)ethy]-5-isoquinoline-sulfonamide (H8) and DT-2 (YGRKKRRQRRRPPLRK(5)H), as well as by the p38 MAPK inhibitor SB203580 [4-(4-fluorophenyl)-2-(4-methylsulfinylphenyl)-5-(4-pyridyl)-1H-imidazole]. Chronoamperometry studies in the anesthetized rat hippocampus support a role for A(3)ARs in SERT regulation in vivo. Together, these results identify a novel, region-specific action of CNS A(3)ARs in the modulation of SERT-mediated 5-HT transport that may be relevant for the etiology and/or therapy of 5-HT-linked brain disorders.
Collapse
Affiliation(s)
- Chong-Bin Zhu
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | | | | | | | | | | |
Collapse
|
38
|
Németh ZH, Bleich D, Csóka B, Pacher P, Mabley JG, Himer L, Vizi ES, Deitch EA, Szabó C, Cronstein BN, Haskó G. Adenosine receptor activation ameliorates type 1 diabetes. FASEB J 2007; 21:2379-88. [PMID: 17405852 PMCID: PMC2225539 DOI: 10.1096/fj.07-8213com] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Growing evidence indicates that adenosine receptors could be promising therapeutic targets in autoimmune diseases. Here we studied the role of adenosine receptors in controlling the course of type 1 diabetes. Diabetes in CD-1 mice was induced by multiple-low-dose-streptozotocin (MLDS) treatment and in nonobese diabetic (NOD) mice by cyclophosphamide injection. The nonselective adenosine receptor agonist 5'-N-ethylcarboxamidoadenosine (NECA) prevented diabetes development in both MLDS-challenged mice and in cyclophosphamide-treated NOD mice. The effect of NECA was reversed by the selective A2B receptor antagonist N-(4-cyanophenyl)-2-[4-(2,3,6,7-tetrahydro-2,6-dioxo-1,3-dipropyl-1H-purin-8-yl)phenoxy]acetamide (MRS 1754). The selective A1 receptor agonist 2-chloro-N6-cyclopentyladenosine (CCPA) and A3 receptor agonist N6-(3-iodobenzyl)-adenosine-5'-N-methyluronamide (IB-MECA) were less efficacious in ameliorating the course of diabetes. NECA inhibited diabetes in A2A receptor KO mice and the selective A2A receptor agonist 2-p-(2-carboxyethyl)phenethyl-amino-5'-N-ethyl-carboxamidoadenosine (CGS21680) had no effect in normal mice, indicating a lack of role of A2A receptors. NECA failed to prevent cytokine-induced beta-cell death in vitro, but NECA strongly suppressed expression of the proinflammatory cytokines TNF-alpha, MIP-1alpha, IL-12, and IFN-gamma in pancreata, endotoxin, or anti-CD3-stimulated splenic cells, and T helper 1 lymphocytes, indicating that the beneficial effect of NECA was due to immunomodulation. These results demonstrate that adenosine receptor ligands are potential candidates for the treatment of type 1 diabetes.
Collapse
MESH Headings
- Adenosine-5'-(N-ethylcarboxamide)/pharmacology
- Adenosine-5'-(N-ethylcarboxamide)/therapeutic use
- Animals
- Cells, Cultured/drug effects
- Cells, Cultured/physiology
- Cytokines/metabolism
- Diabetes Mellitus, Experimental/physiopathology
- Diabetes Mellitus, Experimental/prevention & control
- Diabetes Mellitus, Type 1/pathology
- Diabetes Mellitus, Type 1/physiopathology
- Diabetes Mellitus, Type 1/prevention & control
- Gene Amplification
- Insulin/metabolism
- Male
- Mice
- Mice, Inbred NOD
- Pancreas/drug effects
- Pancreas/metabolism
- Pancreas/pathology
- Purinergic P1 Receptor Agonists
- Receptors, Purinergic P1/genetics
- Receptors, Purinergic P1/physiology
- Th1 Cells/immunology
- Th2 Cells/immunology
Collapse
Affiliation(s)
- Zoltán H. Németh
- Department of Surgery, University of Medicine and Dentistry of New Jersey, New Jersey Medical School, Newark, New Jersey, USA
| | - David Bleich
- Department of Medicine, University of Medicine and Dentistry of New Jersey, New Jersey Medical School, Newark, New Jersey, USA
| | - Balázs Csóka
- Department of Surgery, University of Medicine and Dentistry of New Jersey, New Jersey Medical School, Newark, New Jersey, USA
| | - Pál Pacher
- Section on Oxidative Stress and Tissue Injury, Laboratory of Physiological Studies, National Institutes of Health, National Institute on Alcohol Abuse and Alcoholism, Bethesda, Maryland, USA
| | - Jon G. Mabley
- School of Pharmacy and Biomolecular Sciences, University of Brighton, Cockcroft Building, Brighton, UK
| | - Leonóra Himer
- Department of Pharmacology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Hungary
| | - E. Sylvester Vizi
- Department of Pharmacology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Hungary
| | - Edwin A. Deitch
- Department of Surgery, University of Medicine and Dentistry of New Jersey, New Jersey Medical School, Newark, New Jersey, USA
| | - Csaba Szabó
- Department of Surgery, University of Medicine and Dentistry of New Jersey, New Jersey Medical School, Newark, New Jersey, USA
| | - Bruce N. Cronstein
- Division of Clinical Pharmacology, Department of Medicine, New York University School of Medicine, New York, New York, USA
| | - György Haskó
- Department of Surgery, University of Medicine and Dentistry of New Jersey, New Jersey Medical School, Newark, New Jersey, USA
- Department of Pharmacology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Hungary
- Correspondence: Department of Surgery, UMDNJ-New Jersey Medical School, 185 South Orange Ave., University Heights, Newark, NJ 07103, USA. E-mail:
| |
Collapse
|
39
|
Tang Y, Li X, He J, Lu J, Diwu Z. Real-time and high throughput monitoring of cAMP in live cells using a fluorescent membrane potential-sensitive dye. Assay Drug Dev Technol 2007; 4:461-71. [PMID: 16945018 DOI: 10.1089/adt.2006.4.461] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Adenosine-3',5'-cyclic monophosphate (cAMP) conveys the signals from G-protein coupled receptors (GPCRs) and regulates a variety of downstream cellular events. However, there are few robust assays available for measuring cAMP in live cells. Most of the existing cAMP assays require cell lysis and/or have relatively low throughput. We report a live cell-based cAMP assay that has been developed to record the real-time changes in intracellular cAMP. By employing a mutated cyclic-nucleotide-gated ion channel (CNGC) as the cAMP biosensor, the change of cAMP level is coupled to the change of transmembrane potential that is measured through a new fluorescent membrane potential (MP)-sensitive dye, HLB 021-152. We have successfully used HLB 021-152 for homogeneously monitoring cAMP stimulations in live cells under both serum-containing and serum-free environments. Upon stimulating the endogenous or heterogenous GPCRs on CNGC-cloned human embryonic kidney 293 cells with agonists, the fluorescence signal of HLB 021-152 increases rapidly. It has much greater assay dynamic range than DiSBAC2(3), the existing "gold standard" dye for measuring cellular MP. This new MP dye can be readily formulated for high throughput screening of GPCR modulators either with serum or without serum.
Collapse
Affiliation(s)
- Yi Tang
- AnaSpec Inc., San Jose, CA 95131, USA
| | | | | | | | | |
Collapse
|
40
|
Mustafa SJ, Nadeem A, Fan M, Zhong H, Belardinelli L, Zeng D. Effect of a specific and selective A(2B) adenosine receptor antagonist on adenosine agonist AMP and allergen-induced airway responsiveness and cellular influx in a mouse model of asthma. J Pharmacol Exp Ther 2006; 320:1246-51. [PMID: 17159162 DOI: 10.1124/jpet.106.112250] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
It has been previously proposed that adenosine plays an important role in the pathogenesis of asthma. The proposed mechanism of action for nucleoside adenosine is to activate A(2B) adenosine receptors (AR) and to indirectly modulate levels of mediators in the lung. In vivo data supporting the role of A(2B) AR in airway reactivity and inflammation in allergic animal models are lacking. The present study describes the effects of a selective A(2B) AR antagonist, CVT-6883 [3-ethyl-1-propyl-8-[1-(3-trifluoromethylbenzyl)-1H-pyrazol-4-yl]-3,7-dihydropurine-2,6-dione], on airway reactivity and inflammation in an allergic mouse model of asthma. Mice were sensitized with ragweed (i.p.) on days 1 and 6 and challenged with 0.5% ragweed on days 11, 12, and 13. On day 14, airway reactivity to 5'-N-ethylcarboxamidoadenosine (NECA), AMP, or allergen challenge was measured in terms of enhanced pause (Penh). Aerosolized NECA elicited concentration-dependent increases in Penh, which were significantly attenuated by CVT-6883 (0.4, 1.0, or 2.5 mg/kg i.p.). Aerosolized AMP elicited significant increases in Penh in sensitized mice, and the effect was significantly attenuated by either CVT-6883 (1 mg/kg i.p.) or montelukast (1 mg/kg i.p.). Allergen challenge induced late allergic response in sensitized mice, which was inhibited by CVT-6883 (1 mg/kg i.p.). Allergen challenge also increased the number of cells in bronchoalveolar lavage fluid obtained from sensitized mice, and that was reduced by either CVT-6883 (6 mg/ml aerosolization for 5 min) or theophylline (36 mg/ml aerosolization for 5 min). These results suggest that A(2B)AR antagonism plays an important role in inhibition of airway reactivity and inflammation in this model of allergic asthma.
Collapse
Affiliation(s)
- S Jamal Mustafa
- Department of Physiology and Pharmacology, School of Medicine, West Virginia University, Morgantown, WV 26506, USA.
| | | | | | | | | | | |
Collapse
|
41
|
Ryzhov S, McCaleb JL, Goldstein AE, Biaggioni I, Feoktistov I. Role of adenosine receptors in the regulation of angiogenic factors and neovascularization in hypoxia. J Pharmacol Exp Ther 2006; 320:565-72. [PMID: 17132813 DOI: 10.1124/jpet.106.114850] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Because hypoxia increases extracellular adenosine levels and stimulates angiogenesis, we evaluated the relative roles of reduced oxygen concentrations and adenosine receptor activation in the production of angiogenic factors. In vitro, we analyzed the effects of hypoxia and adenosine on the secretion of angiogenic factors from human microvascular endothelial cells (HMEC-1). To study the effects of hypoxia alone, we scavenged adenosine from the hypoxic medium with adenosine deaminase, and we used the stable adenosine analog 5'-N-ethylcarboxamidoadenosine (NECA) to study the effects of stimulation of adenosine receptors. In the absence of adenosine, hypoxia stimulated vascular endothelial growth factor (VEGF) but not interleukin-8 (IL-8) secretion from HMEC-1. In contrast, NECA stimulated both VEGF and IL-8 secretion. VEGF secretion was increased 1.9 +/- 0.04-fold with NECA (10 microM) and 1.7 +/- 0.1-fold with hypoxia (5% O(2)) but 3.8 +/- 0.1-fold when these two stimuli were combined. Thus, adenosine receptors act in a cooperative fashion with hypoxia to stimulate VEGF and induce IL-8 secretion not stimulated by hypoxia alone. In vivo, antagonism of adenosine receptors with caffeine abrogated VEGF up-regulation induced by local injection of NECA into the mouse hind limb and produced a 46% reduction of neovascularization in a mouse ischemic hind limb model. Our study suggests that adenosine actions are not redundant but rather are complementary to the direct effects of hypoxia. Stimulation of adenosine receptors not only contributes to the overall effect of hypoxia but also has additional actions in the regulation of angiogenic factors. Thus, adenosine receptors represent a potential therapeutic target for regulation of neovascularization.
Collapse
Affiliation(s)
- Sergey Ryzhov
- Department of Medicine, Vanderbilt University, Nashville, TN 37232-6300, USA
| | | | | | | | | |
Collapse
|
42
|
Ramanathan M, Pinhal-Enfield G, Hao I, Leibovich SJ. Synergistic up-regulation of vascular endothelial growth factor (VEGF) expression in macrophages by adenosine A2A receptor agonists and endotoxin involves transcriptional regulation via the hypoxia response element in the VEGF promoter. Mol Biol Cell 2006; 18:14-23. [PMID: 17065555 PMCID: PMC1751314 DOI: 10.1091/mbc.e06-07-0596] [Citation(s) in RCA: 94] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Macrophages are an important source of vascular endothelial growth factor (VEGF). Adenosine A2A receptor (A2AR) agonists with Toll-like receptor (TLR) 2, 4, 7, and 9 agonists synergistically induce macrophage VEGF expression. We show here using VEGF promoter-luciferase reporter constructs that the TLR4 agonist Escherichia coli lipopolysaccharide (LPS) and the A2AR agonists NECA and CGS21680 synergistically augment VEGF transcription in macrophages and that the HRE in the VEGF promoter is essential for this transcription. We examined whether LPS and/or NECA induce HIF-1alpha expression. HIF-1alpha mRNA levels were increased in LPS-treated macrophages in an NF-kappaB-dependent manner; NECA strongly increased these levels in an A2AR-dependent manner. LPS induced luciferase expression from a HIF-1alpha promoter-luciferase construct in an A2AR-independent manner. Further stimulation with NECA did not increase HIF-1alpha promoter activity, indicating that the A2AR-dependent increase in HIF-1alpha mRNA is post-transcriptional. LPS/NECA treatment also increased HIF-1alpha protein and DNA binding levels. Deletion of putative NF-kappaB-binding sites from the VEGF promoter did not affect LPS/NECA-induced VEGF promoter activity, suggesting that NF-kappaB is not directly involved in VEGF transcription. Taken together, these data indicate that LPS/NECA-induced VEGF expression involves transcriptional regulation of the VEGF promoter by HIF-1alpha through the HRE. HIF-1alpha is transcriptionally induced by LPS and post-transcriptionally up-regulated in an A2AR-dependent manner.
Collapse
Affiliation(s)
- Madhuri Ramanathan
- Department of Cell Biology and Molecular Medicine and The Cardiovascular Research Institute, New Jersey Medical School, University of Medicine and Dentistry of New Jersey, Newark, NJ 07103
| | - Grace Pinhal-Enfield
- Department of Cell Biology and Molecular Medicine and The Cardiovascular Research Institute, New Jersey Medical School, University of Medicine and Dentistry of New Jersey, Newark, NJ 07103
| | - Irene Hao
- Department of Cell Biology and Molecular Medicine and The Cardiovascular Research Institute, New Jersey Medical School, University of Medicine and Dentistry of New Jersey, Newark, NJ 07103
| | - Samuel Joseph Leibovich
- Department of Cell Biology and Molecular Medicine and The Cardiovascular Research Institute, New Jersey Medical School, University of Medicine and Dentistry of New Jersey, Newark, NJ 07103
| |
Collapse
|
43
|
Rossi M, Dimida A, Dell'anno MT, Trincavelli ML, Agretti P, Giorgi F, Corsini GU, Pinchera A, Vitti P, Tonacchera M, Maggio R. The thyroid disruptor 1,1,1-trichloro-2,2-bis(p-chlorophenyl)-ethane appears to be an uncompetitive inverse agonist for the thyrotropin receptor. J Pharmacol Exp Ther 2006; 320:465-74. [PMID: 17062616 DOI: 10.1124/jpet.106.113613] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In this study, we aimed at establishing whether two previously identified thyroid disruptors, the insecticide 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) and Aroclor 1254 (a complex mixture of polychlorinated water), may inhibit thyrotropin (TSH) receptor (TSHr) activity. DDT and Aroclor 1254 were shown to inhibit both the basal and bovine TSH (bTSH)-stimulated accumulation of cAMP in Chinese hamster ovary (CHO)-K1 cells stably transfected with the TSHr. Furthermore, both DDT and Aroclor 1254 did indeed prevent cAMP accumulation, as induced by the constitutive activity of a point mutant TSHr(I486M) transiently transfected in African green monkey kidney fibroblast (COS)-7 cells. Neither trypsin digestion of the extracellular domain (ECD) nor deletion of the ECD in a mutant TSHr trunk transiently transfected in COS-7 cells counteracted the inhibitory activity of DDT and Aroclor 1254. DDT exerted a weak inhibitory activity against forskolin in both CHO-K1 and COS-7 cells, whereas it was nil against the agonists dopamine and 5'-(N-ethyl-carboxamido)-adenosine (NECA) in CHO cells stably transfected with the dopamine D1 receptor and in COS-7 cells transiently transfected with the adenosine type 2a receptor (A2a) receptor. Furthermore, DDT was inactive against the stimulation by isoproterenol of the endogenously expressed beta2 adrenergic receptor in COS-7 cells. Conversely, Aroclor 1254 inhibited completely forskolin activity in CHO-K1 cells but not in COS-7 cells. Furthermore, it did not prevent accumulation of cAMP as induced by NECA in A2a transfected cells. The analog of DDT, diphenylethylene, was inactive against bTSH-induced increase in cAMP in CHO-K1 cells stably transfected with the TSHr. We interpreted these results as indicating that DDT and possibly Aroclor 1254 may have an uncompetitive inverse agonist activity for the TSHr.
Collapse
Affiliation(s)
- Mario Rossi
- Department of Neurosciences, Centre of Excellence for the Study of Damage to the Nervous and Endocrine Systems Produced by Environmental, Alimentary, and Pharmacological Agents, University of Pisa, Pisa, Italy
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
44
|
Suzuki T, Namba K, Tsuga H, Nakata H. Regulation of pharmacology by hetero-oligomerization between A1 adenosine receptor and P2Y2 receptor. Biochem Biophys Res Commun 2006; 351:559-65. [PMID: 17070771 DOI: 10.1016/j.bbrc.2006.10.075] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2006] [Accepted: 10/16/2006] [Indexed: 11/19/2022]
Abstract
Adenosine and ATP/UTP are main components of the purinergic system that modulate cellular and tissue functions via specific adenosine and P2 receptors, respectively. Here, we explored the possibility that A(1) adenosine receptor (A(1)R) and P2Y(2) receptor (P2Y(2)R) form heterodimers with novel pharmacological properties. Coimmunoprecipitation showed these receptors directly associate in A(1)R/P2Y(2)R-cotransfected HEK293T cells. Agonist binding by the A(1)R was significantly inhibited by P2Y(2)R agonists only in membranes from cotransfected cells. The functional activity of A(1)R, as indicated by the G(i/o)-mediated inhibition of adenylyl cyclase, in the cotransfected cells was attenuated by the simultaneous addition of A(1)R and P2Y(2)R agonists. The increase in intracellular Ca(2+) levels induced by P2Y(2)R activation of G(q/11) was synergistically enhanced by the simultaneous addition of an A(1)R agonist in the coexpressing cells. These results suggest that oligomerization of A(1)R and P2Y(2)R generates a unique complex in which the simultaneous activation of the two receptors induces a structural alteration that interferes signaling via G(i/o) but enhances signaling via G(q/11).
Collapse
Affiliation(s)
- Tokiko Suzuki
- Department of Molecular Cell Signaling, Tokyo Metropolitan Institute for Neuroscience, 2-6 Musashidai, Fuchu, Tokyo 183-8526, Japan
| | | | | | | |
Collapse
|
45
|
Grden M, Podgorska M, Kocbuch K, Szutowicz A, Pawelczyk T. Expression of adenosine receptors in cardiac fibroblasts as a function of insulin and glucose level. Arch Biochem Biophys 2006; 455:10-7. [PMID: 17011509 DOI: 10.1016/j.abb.2006.08.022] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2006] [Revised: 08/28/2006] [Accepted: 08/28/2006] [Indexed: 11/26/2022]
Abstract
Adenosine among other factors is known to regulate the growth and function of cardiac fibroblasts (CFs). Its action is mediated by cell-surface receptors linked to a variety of signaling systems. The goal of present work was to examine the effects of glucose and insulin on adenosine receptors (ARs) mRNA and protein level in primary culture of rat CFs by means of real-time PCR and Western blot. Elevated glucose level increased the expression of A(1)-AR, A(2A)-AR, decreased the expression of A(3)-AR, and had no effect on A(2B)-AR expression. On the other hand insulin suppressed the expression of A(1)-AR, and A(2B)-AR, and had no effect on A(2A)-AR and A(3)-AR expression. Our measurements showed that accumulation of cAMP in response to ARs agonists correlated well with the changes in receptors expression level. These results indicate that changes in glucose and insulin level independently and differentially regulate the ARs expression and functional state in CFs.
Collapse
Affiliation(s)
- Marzena Grden
- Department of Molecular Medicine, Medical University of Gdansk, 80-211 Gdansk, Poland
| | | | | | | | | |
Collapse
|
46
|
Faria M, Magalhães-Cardoso T, Lafuente-de-Carvalho JM, Correia-de-Sá P. Corpus Cavernosum from Men with Vasculogenic Impotence Is Partially Resistant to Adenosine Relaxation due to Endothelial A2B Receptor Dysfunction. J Pharmacol Exp Ther 2006; 319:405-13. [PMID: 16837560 DOI: 10.1124/jpet.106.107821] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Although adenosine has been implicated in penile erection in human males, the receptor subtype responsible for adenosine regulation of human corpus cavernosum (HCC) smooth muscle tone is still a matter of debate. Using selective adenosine agonists and antagonists, we aimed at characterizing the adenosine receptors mediating relaxation of precontracted (with 1 microM phenylephrine) HCC strips. HCC specimens were collected from control subjects (organ donors) and from patients with severe vasculogenic erectile dysfunction (ED). In control subjects, adenosine and 5'-N-ethyl-carboxamide adenosine (NECA) fully relaxed HCC. The selective A(2A) receptor agonist 2-[4-(2-p-carboxy ethyl)phenylamino]-5'-N-ethylcarboxamido adenosine (CGS21680C) produced only a partial relaxation (30-50%) of HCC, which could be further enhanced by simultaneous application of 100 microM NECA. The selective A(2B) receptor antagonist N-(4-acetylphenyl)-2-[4-(2,3,6,7-tetrahydro-2,6-dioxo-1,3-dipropyl-1H-purin-8-il)phenoxy] acetamida (MRS1706) (10 nM) attenuated NECA-induced relaxation without affecting CGS21680C action. The A(2A) receptor antagonist 4-{2-[7-amino-2-(2-furyl)[1,2,4]triazolo-[2,3-a][1,3,5]triazin-5-ylamino]ethyl}phenol (ZM241385) (50 nM) consistently reduced the actions of both agonists. In contrast to CGS21680C, NECA-induced relaxation was attenuated when endothelial production of NO and prostanoids was reduced by 100 microM N(G)-nitro-l-arginine and 10 microM indomethacin, respectively. HCC strips from patients with vasculogenic ED were partially resistant to NECA but kept relaxation to CGS21680C; the remaining effect was sensitive to blockade of A(2A) receptors with 50 nM ZM241385. Data suggest that adenosine regulates HCC smooth muscle tone through the activation of two receptor populations, CGS21680C-sensitive (A(2A)) and -insensitive (A(2B)) receptors, located on smooth muscle fibers and on endothelial cells, respectively. Endothelial dysfunction may be correlated with a loss of adenosine A(2B) receptor activity in penile vessels from men with vasculogenic ED.
Collapse
Affiliation(s)
- Miguel Faria
- Laboratório de Farmacologia, Instituto de Ciências Biomédicas de Abel Salazar, Universidade do Porto, L. Prof. Abel Salazar 2, 4099-003 Porto, Portugal
| | | | | | | |
Collapse
|
47
|
Jenner TL, Rose'Meyer RB. Loss of vascular adenosine A1 receptors with age in the rat heart. Vascul Pharmacol 2006; 45:341-9. [PMID: 16824805 DOI: 10.1016/j.vph.2006.05.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2006] [Revised: 04/28/2006] [Accepted: 05/11/2006] [Indexed: 10/24/2022]
Abstract
OBJECTIVE To investigate the effects of age on adenosine A1 receptor (ADORA1) mediated vascular, inotropic and chronotropic functional responses in isolated rat hearts. METHODS NECA (5'-(N-ethylcarboxamido)adenosine) and R-PIA (R-N6-(1-methyl-2-phenylethyl)adenosine) concentration-response curves were produced in Langendorff prepared hearts isolated from immature (6 weeks), young (16 weeks) and mature (52 weeks) male Wistar rats and the effects of DPCPX (ADORA1 antagonist, 8-cyclopentyl-1,3-dipropylxanthine, 30 nM) and pertussis toxin pre-treatment (PTX, 48 h, 10 microg/kg i.p., inhibits G(i/o)-protein) were observed. RESULTS NECA mediated coronary vasodilation and induced biphasic concentration-response curves in hearts from immature rats (pEC50 8.5 (8.1-8.9) and 11.3 (10.3-12.3)). At the low sensitivity site, the potency of NECA increased in young but not mature rats and remained unchanged at the high sensitivity site. Both DPCPX and PTX each blocked NECA at the high sensitivity site in immature rats, producing monophasic concentration-response curves (pEC50 8.6 (8.5-9.9) for DPCPX and pEC50 8.7 (8.3-9.0) for PTX), but not in young and mature rats. A vasoconstrictor response was observed at low NECA concentrations in hearts from PTX pre-treated immature rats, but not in hearts from young and mature rats, and the response was inhibited by DPCPX. No age related changes were observed in R-PIA mediated negative inotropic and chronotropic responses (P>0.05). CONCLUSION ADORA1 mediates a vasodilator response as well as a vasoconstrictor response in the coronary resistance vessels; the latter occurs via a PTX-insensitive pathway and declines with age.
Collapse
Affiliation(s)
- Tamsin L Jenner
- School of Medical Sciences, Griffith University Gold Coast Campus, Southport, QLD 9726, Australia.
| | | |
Collapse
|
48
|
Abstract
Adenosine stimulates contraction of airway smooth muscle, but the mechanism is widely considered indirect, depending on release of contractile agonists from mast cells and nerves. The goal was to determine whether adenosine, by itself, directly regulates calcium signaling in human bronchial smooth muscle cells (HBSMC). Primary cultures of HBSMC from normal subjects were loaded with fura 2-AM, and cytosolic calcium concentrations ([Ca(2+)](i)) were determined ratiometrically by imaging single cells. The nonselective adenosine receptor agonist, 5'-N-ethylcarboxamidoadenosine (NECA), and the adenosine A(1) receptor agonist, N(6)-cyclopentyladenosine (CPA), both stimulated rapid, transient increases in [Ca(2+)](i). In contrast, there were no calcium responses to 2-p-(2-carboxyethyl)phenethylamino-5'-N-ethylcarboxamido-adenosine (100 nM) or N(6)-(3-iodobenzyl)-adenosine-5'-N-methyluronamide (100 nM), selective agonists at adenosine A(2A) receptors and adenosine A(3) receptors, respectively. Calcium responses to NECA and CPA were inhibited by 8-cyclopentyl-1,3-dipropylxanthine, an adenosine A(1) receptor antagonist, and by pertussis toxin (PTX). In other experiments, NECA stimulated calcium transients in the absence of extracellular calcium, but not when cells were preincubated in cyclopiazonic acid or thapsigargin to empty intracellular calcium stores. Calcium responses were attenuated by xestospongin C and 2-aminoethoxydiphenylborane, inhibitors of inositol trisphosphate (IP(3)) receptors, and by U73122, an inhibitor of phospholipase C. It was concluded that stimulation of adenosine A(1) receptors on HBSMC rapidly mobilizes intracellular calcium stores by a mechanism dependent on PTX-sensitive G proteins, and IP(3) signaling. These findings suggest that, in addition to its well-established indirect effects on HBSMC, adenosine also has direct effects on contractile signaling pathways.
Collapse
Affiliation(s)
- Michael F Ethier
- Department of Medicine, 364 Plantation Street, LRB, Room 370A, University of Massachusetts Medical School, Worcester, 01605, USA.
| | | |
Collapse
|
49
|
Ryzhov S, Goldstein AE, Biaggioni I, Feoktistov I. Cross-talk between G(s)- and G(q)-coupled pathways in regulation of interleukin-4 by A(2B) adenosine receptors in human mast cells. Mol Pharmacol 2006; 70:727-35. [PMID: 16707627 DOI: 10.1124/mol.106.022780] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Human mast cells express functional A(2A) and A(2B) adenosine receptors. However, only stimulation of A(2B), not A(2A), leads to secretion of interleukin (IL)-4, an important step in adenosine receptor-mediated induction of IgE synthesis by B-cells. In this study, we investigate intracellular pathways that link stimulation of A(2B) receptors to IL-4 up-regulation in HMC-1 mast cells. Both A(2A) and A(2B) receptors couple to G(s) proteins and stimulate adenylate cyclase, but only A(2B) stimulates phospholipase Cbeta through coupling to G(q) proteins leading to activation of protein kinase C and calcium mobilization. Inhibition of phospholipase Cbeta completely blocked A(2B) receptor-dependent IL-4 secretion. The protein kinase C inhibitor 2-{8-[(dimethylamino)-methyl]-6,7,8,9-tetrahydropyrido[1,2-a]indol-3-yl}-3-(1-methyl-1H-indol-3-yl)maleimide (Ro-32-0432) had no effect on A(2B) receptor-mediated IL-4 secretion but inhibited phorbol 12-myristate 13-acetate-stimulated IL-4 secretion. In contrast, chelation of intracellular Ca(2+) inhibited both A(2B) receptor- and ionomycin-dependent IL-4 secretion. This Ca(2+)-sensitive pathway probably includes calcineurin and nuclear factor of activated T cells, because A(2B) receptor-dependent IL-4 secretion was blocked with cyclosporin A or 11R-VIVIT peptide. G(s)-linked pathways also play a role in the A(2B) receptor-dependent stimulation of IL-4 secretion; inhibition of adenylate cyclase or protein kinase A attenuated A(2B) receptor-dependent IL-4 secretion. Although stimulation of adenylate cyclase with forskolin did not increase IL-4 secretion on its own, it potentiated the effect of Pasteurella multocida toxin by 2-fold and ionomycin by 3-fold. Both forskolin and stimulation of A(2B) receptors up-regulated NFATc1 protein levels. We conclude that A(2B) receptors up-regulate IL-4 through G(q) signaling that is potentiated via cross-talk with G(s)-coupled pathways.
Collapse
Affiliation(s)
- Sergey Ryzhov
- Divisions of Cardiovascular Medicine, Vanderbilt University, Nashville, TN 37232-6300, USA
| | | | | | | |
Collapse
|
50
|
Ishibashi T, Dakin KA, Stevens B, Lee PR, Kozlov SV, Stewart CL, Fields RD. Astrocytes promote myelination in response to electrical impulses. Neuron 2006; 49:823-32. [PMID: 16543131 PMCID: PMC1474838 DOI: 10.1016/j.neuron.2006.02.006] [Citation(s) in RCA: 490] [Impact Index Per Article: 27.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2005] [Revised: 12/30/2005] [Accepted: 02/03/2006] [Indexed: 01/07/2023]
Abstract
Myelin, the insulating layers of membrane wrapped around axons by oligodendrocytes, is essential for normal impulse conduction. It forms during late stages of fetal development but continues into early adult life. Myelination correlates with cognitive development and can be regulated by impulse activity through unknown molecular mechanisms. Astrocytes do not form myelin, but these nonneuronal cells can promote myelination in ways that are not understood. Here, we identify a link between myelination, astrocytes, and electrical impulse activity in axons that is mediated by the cytokine leukemia inhibitory factor (LIF). These findings show that LIF is released by astrocytes in response to ATP liberated from axons firing action potentials, and LIF promotes myelination by mature oligodendrocytes. This activity-dependent mechanism promoting myelination could regulate myelination according to functional activity or environmental experience and may offer new approaches to treating demyelinating diseases.
Collapse
Affiliation(s)
- Tomoko Ishibashi
- Nervous System Development and Plasticity Section, National Institute of Child Health and Human Development, Bethesda, Maryland 20892, USA
| | | | | | | | | | | | | |
Collapse
|