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Hayes G, Pinto J, Sparks SN, Wang C, Suri S, Bulte DP. Vascular smooth muscle cell dysfunction in neurodegeneration. Front Neurosci 2022; 16:1010164. [PMID: 36440263 PMCID: PMC9684644 DOI: 10.3389/fnins.2022.1010164] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Accepted: 10/24/2022] [Indexed: 09/01/2023] Open
Abstract
Vascular smooth muscle cells (VSMCs) are the key moderators of cerebrovascular dynamics in response to the brain's oxygen and nutrient demands. Crucially, VSMCs may provide a sensitive biomarker for neurodegenerative pathologies where vasculature is compromised. An increasing body of research suggests that VSMCs have remarkable plasticity and their pathophysiology may play a key role in the complex process of neurodegeneration. Furthermore, extrinsic risk factors, including environmental conditions and traumatic events can impact vascular function through changes in VSMC morphology. VSMC dysfunction can be characterised at the molecular level both preclinically, and clinically ex vivo. However the identification of VSMC dysfunction in living individuals is important to understand changes in vascular function at the onset and progression of neurological disorders such as dementia, Alzheimer's disease, and Parkinson's disease. A promising technique to identify changes in the state of cerebral smooth muscle is cerebrovascular reactivity (CVR) which reflects the intrinsic dynamic response of blood vessels in the brain to vasoactive stimuli in order to modulate regional cerebral blood flow (CBF). In this work, we review the role of VSMCs in the most common neurodegenerative disorders and identify physiological systems that may contribute to VSMC dysfunction. The evidence collected here identifies VSMC dysfunction as a strong candidate for novel therapeutics to combat the development and progression of neurodegeneration, and highlights the need for more research on the role of VSMCs and cerebrovascular dynamics in healthy and diseased states.
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Affiliation(s)
- Genevieve Hayes
- Department of Engineering Science, Institute of Biomedical Engineering, University of Oxford, Oxford, United Kingdom
| | - Joana Pinto
- Department of Engineering Science, Institute of Biomedical Engineering, University of Oxford, Oxford, United Kingdom
| | - Sierra N. Sparks
- Department of Engineering Science, Institute of Biomedical Engineering, University of Oxford, Oxford, United Kingdom
| | - Congxiyu Wang
- Department of Psychiatry, University of Oxford, Oxford, United Kingdom
- Oxford Centre for Human Brain Activity, Wellcome Centre for Integrative Neuroimaging, University of Oxford, Oxford, United Kingdom
| | - Sana Suri
- Department of Psychiatry, University of Oxford, Oxford, United Kingdom
- Oxford Centre for Human Brain Activity, Wellcome Centre for Integrative Neuroimaging, University of Oxford, Oxford, United Kingdom
| | - Daniel P. Bulte
- Department of Engineering Science, Institute of Biomedical Engineering, University of Oxford, Oxford, United Kingdom
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Adenosine Receptors Profile in Fibromuscular Dysplasia. Biomedicines 2022; 10:biomedicines10112831. [PMID: 36359350 PMCID: PMC9687922 DOI: 10.3390/biomedicines10112831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Revised: 10/19/2022] [Accepted: 11/02/2022] [Indexed: 11/09/2022] Open
Abstract
Fibromuscular dysplasia (FMD) is a non-inflammatory vascular disease that is characterized by unexplained systemic hypertension occurring in young people, associated with arterial stenosis, aneurysm rupture, intracranial/renal infarction, and stroke. Although the gold standard for the diagnosis remains catheter-angiography, biological markers would be helpful due to the delay from first symptom to diagnosis. Adenosine is an ATP derivative, that may be implicated in FMD pathophysiology. We hypothesized that changes in adenosine blood level (ABL) and production of adenosine receptors may be associated with FMD. Using peripheral blood mononuclear cells, we evaluated A1, A2A, and A2B receptor production by Western blot, in 67 patients (17 men and 50 women, mean (range) age 55 (29−77) years and 40 controls, 10 men and 30 women, mean (range) age 56 (37−70)). ABL was evaluated by liquid chromatography, mass spectrometry. ABL was significantly higher in patients vs. controls, mean (range): 1.7 (0.7−3) µmol/L vs. controls 0.6 (0.4−0.8) µmol/L (+180%) p < 0.001. While A1R and A2AR production did not differ in patients and controls, we found an over-production of A2BR in patients: 1.70 (0.90−2.40; arbitrary units) vs. controls = 1.03 (0.70−1.40), mean + 65% (p < 0.001). A2BR production with a cut off of 1.3 arbitrary units, gives a good sensitivity and specificity for the diagnosis. Production measurement of A2BR on monocytes and ABL could help in the diagnosis, especially in atypical or with poor symptoms.
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Effendi WI, Nagano T, Kobayashi K, Nishimura Y. Focusing on Adenosine Receptors as a Potential Targeted Therapy in Human Diseases. Cells 2020; 9:E785. [PMID: 32213945 PMCID: PMC7140859 DOI: 10.3390/cells9030785] [Citation(s) in RCA: 78] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Revised: 03/21/2020] [Accepted: 03/23/2020] [Indexed: 02/07/2023] Open
Abstract
Adenosine is involved in a range of physiological and pathological effects through membrane-bound receptors linked to G proteins. There are four subtypes of adenosine receptors, described as A1AR, A2AAR, A2BAR, and A3AR, which are the center of cAMP signal pathway-based drug development. Several types of agonists, partial agonists or antagonists, and allosteric substances have been synthesized from these receptors as new therapeutic drug candidates. Research efforts surrounding A1AR and A2AAR are perhaps the most enticing because of their concentration and affinity; however, as a consequence of distressing conditions, both A2BAR and A3AR levels might accumulate. This review focuses on the biological features of each adenosine receptor as the basis of ligand production and describes clinical studies of adenosine receptor-associated pharmaceuticals in human diseases.
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Affiliation(s)
- Wiwin Is Effendi
- Division of Respiratory Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan; (W.I.E.); (K.K.); (Y.N.)
- Department of Pulmonology and Respiratory Medicine, Medical Faculty of Airlangga University, Surabaya 60131, Indonesia
| | - Tatsuya Nagano
- Division of Respiratory Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan; (W.I.E.); (K.K.); (Y.N.)
| | - Kazuyuki Kobayashi
- Division of Respiratory Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan; (W.I.E.); (K.K.); (Y.N.)
| | - Yoshihiro Nishimura
- Division of Respiratory Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan; (W.I.E.); (K.K.); (Y.N.)
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Smith SA, Newby AC, Bond M. Ending Restenosis: Inhibition of Vascular Smooth Muscle Cell Proliferation by cAMP. Cells 2019; 8:cells8111447. [PMID: 31744111 PMCID: PMC6912325 DOI: 10.3390/cells8111447] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Revised: 11/14/2019] [Accepted: 11/14/2019] [Indexed: 12/17/2022] Open
Abstract
Increased vascular smooth muscle cell (VSMC) proliferation contributes towards restenosis after angioplasty, vein graft intimal thickening and atherogenesis. The second messenger 3′ 5′ cyclic adenosine monophosphate (cAMP) plays an important role in maintaining VSMC quiescence in healthy vessels and repressing VSMC proliferation during resolution of vascular injury. Although the anti-mitogenic properties of cAMP in VSMC have been recognised for many years, it is only recently that we gained a detailed understanding of the underlying signalling mechanisms. Stimuli that elevate cAMP in VSMC inhibit G1-S phase cell cycle progression by inhibiting expression of cyclins and preventing S-Phase Kinase Associated Protein-2 (Skp2-mediated degradation of cyclin-dependent kinase inhibitors. Early studies implicated inhibition of MAPK signalling, although this does not fully explain the anti-mitogenic effects of cAMP. The cAMP effectors, Protein Kinase A (PKA) and Exchange Protein Activated by cAMP (EPAC) act together to inhibit VSMC proliferation by inducing Cyclic-AMP Response Element Binding protein (CREB) activity and inhibiting members of the RhoGTPases, which results in remodelling of the actin cytoskeleton. Cyclic-AMP induced actin remodelling controls proliferation by modulating the activity of Serum Response Factor (SRF) and TEA Domain Transcription Factors (TEAD), which regulate expression of genes required for proliferation. Here we review recent research characterising these mechanisms, highlighting novel drug targets that may allow the anti-mitogenic properties of cAMP to be harnessed therapeutically to limit restenosis.
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Affiliation(s)
| | | | - Mark Bond
- Correspondence: ; Tel.: +44-117-3423586
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Nitschke Y, Yan Y, Buers I, Kintziger K, Askew K, Rutsch F. ENPP1-Fc prevents neointima formation in generalized arterial calcification of infancy through the generation of AMP. Exp Mol Med 2018; 50:1-12. [PMID: 30369595 PMCID: PMC6204430 DOI: 10.1038/s12276-018-0163-5] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Revised: 05/08/2018] [Accepted: 07/12/2018] [Indexed: 12/12/2022] Open
Abstract
Generalized arterial calcification of infancy (GACI) is associated with widespread arterial calcification and stenoses and is caused by mutations in ENPP1. ENPP1 encodes for ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1), which cleaves ATP to generate inorganic pyrophosphate (PPi) and adenosine monophosphate (AMP) extracellularly. The current study was designed to define the prevalence of arterial stenoses in GACI individuals and to identify the mechanism through which ENPP1 deficiency causes intimal proliferation. Furthermore, we aimed to effectively prevent and treat neointima formation in an animal model of GACI through the systemic administration of recombinant human (rh)ENPP1-Fc protein. Based on a literature review, we report that arterial stenoses are present in at least 72.4% of GACI cases. We evaluated the effect of rhENPP1-Fc on ENPP1-silenced human vascular smooth muscle cells (VSMCs) and on induced intimal proliferation in Enpp1-deficient ttw/ttw mice treated with carotid ligation. We demonstrate that silencing ENPP1 in VSMCs resulted in a tenfold increase in proliferation relative to that of cells transfected with negative control siRNA. The addition of rhENPP1-Fc, AMP or adenosine restored the silenced ENPP1-associated proliferation. In contrast, neither PPi nor etidronate, a current off-label treatment for GACI, had an effect on VSMC proliferation. Furthermore, subcutaneous rhENPP1-Fc protein replacement was effective in preventing and treating intimal hyperplasia induced by carotid ligation in an animal model of GACI. We conclude that ENPP1 inhibits neointima formation by generating AMP. RhENPP1-Fc may serve as an approach for the effective prevention and treatment of arterial stenoses in GACI. A protein replacement therapy may prove useful in tackling calcification and narrowing of the arteries in babies with a severe genetic disorder. Generalized Arterial Calcification of Infancy (GACI) is a rare condition in which infants’ arteries become calcified and their blood vessels internally scarred. It often leads to congestive heart failure. The ENPP1 gene encodes a protein that is crucial to preventing excess calcium build-up in the body. Mutations in the ENPP1 gene lead to GACI, but no therapies for the condition exist. Now, Frank Rutsch at Muenster University Children’s Hospital in Germany and co-workers have shown that administering a protein replacement can inhibit blood vessel scarring and arterial clogging in GACI mice models and in human stem cell cultures. The protein replacement boosts production of a key metabolic molecule called adenosine monophosphate.
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Affiliation(s)
- Yvonne Nitschke
- Department of General Pediatrics, Münster University Children's Hospital, Albert-Schweitzer-Campus 1, D-48149, Münster, Germany.,Cells in Motion Cluster of Excellence, Münster University, Münster, Germany
| | - Yan Yan
- Alexion Pharmaceuticals, 100 College St, New Haven, CT, USA
| | - Insa Buers
- Department of General Pediatrics, Münster University Children's Hospital, Albert-Schweitzer-Campus 1, D-48149, Münster, Germany.,Cells in Motion Cluster of Excellence, Münster University, Münster, Germany
| | - Kristina Kintziger
- Department of General Pediatrics, Münster University Children's Hospital, Albert-Schweitzer-Campus 1, D-48149, Münster, Germany
| | - Kim Askew
- Alexion Pharmaceuticals, 100 College St, New Haven, CT, USA
| | - Frank Rutsch
- Department of General Pediatrics, Münster University Children's Hospital, Albert-Schweitzer-Campus 1, D-48149, Münster, Germany. .,Cells in Motion Cluster of Excellence, Münster University, Münster, Germany.
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Alencar AKN, Montes GC, Barreiro EJ, Sudo RT, Zapata-Sudo G. Adenosine Receptors As Drug Targets for Treatment of Pulmonary Arterial Hypertension. Front Pharmacol 2017; 8:858. [PMID: 29255415 PMCID: PMC5722832 DOI: 10.3389/fphar.2017.00858] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Accepted: 11/09/2017] [Indexed: 01/05/2023] Open
Abstract
Pulmonary arterial hypertension (PAH) is a clinical condition characterized by pulmonary arterial remodeling and vasoconstriction, which promote chronic vessel obstruction and elevation of pulmonary vascular resistance. Long-term right ventricular (RV) overload leads to RV dysfunction and failure, which are the main determinants of life expectancy in PAH subjects. Therapeutic options for PAH remain limited, despite the introduction of prostacyclin analogs, endothelin receptor antagonists, phosphodiesterase type 5 inhibitors, and soluble guanylyl cyclase stimulators within the last 15 years. Through addressing the pulmonary endothelial and smooth muscle cell dysfunctions associated with PAH, these interventions delay disease progression but do not offer a cure. Emerging approaches to improve treatment efficacy have focused on beneficial actions to both the pulmonary vasculature and myocardium, and several new targets have been investigated and validated in experimental PAH models. Herein, we review the effects of adenosine and adenosine receptors (A1, A2A, A2B, and A3) on the cardiovascular system, focusing on the A2A receptor as a pharmacological target. This receptor induces pulmonary vascular and heart protection in experimental models, specifically models of PAH. Targeting the A2A receptor could potentially serve as a novel and efficient approach for treating PAH and concomitant RV failure. A2A receptor activation induces pulmonary endothelial nitric oxide synthesis, smooth muscle cell hyperpolarization, and vasodilation, with important antiproliferative activities through the inhibition of collagen deposition and vessel wall remodeling in the pulmonary arterioles. The pleiotropic potential of A2A receptor activation is highlighted by its additional expression in the heart tissue, where it participates in the regulation of intracellular calcium handling and maintenance of heart chamber structure and function. In this way, the activation of A2A receptor could prevent the production of a hypertrophic and dysfunctional phenotype in animal models of cardiovascular diseases.
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Affiliation(s)
- Allan K N Alencar
- Programa de Pesquisa em Desenvolvimento de Fármacos, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Guilherme C Montes
- Programa de Pesquisa em Desenvolvimento de Fármacos, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Eliezer J Barreiro
- Programa de Pesquisa em Desenvolvimento de Fármacos, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Roberto T Sudo
- Programa de Pesquisa em Desenvolvimento de Fármacos, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Gisele Zapata-Sudo
- Programa de Pesquisa em Desenvolvimento de Fármacos, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
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7
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The Adenosinergic System as a Therapeutic Target in the Vasculature: New Ligands and Challenges. Molecules 2017; 22:molecules22050752. [PMID: 28481238 PMCID: PMC6154114 DOI: 10.3390/molecules22050752] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 04/24/2017] [Accepted: 05/02/2017] [Indexed: 12/20/2022] Open
Abstract
Adenosine is an adenine base purine with actions as a modulator of neurotransmission, smooth muscle contraction, and immune response in several systems of the human body, including the cardiovascular system. In the vasculature, four P1-receptors or adenosine receptors—A1, A2A, A2B and A3—have been identified. Adenosine receptors are membrane G-protein receptors that trigger their actions through several signaling pathways and present differential affinity requirements. Adenosine is an endogenous ligand whose extracellular levels can reach concentrations high enough to activate the adenosine receptors. This nucleoside is a product of enzymatic breakdown of extra and intracellular adenine nucleotides and also of S-adenosylhomocysteine. Adenosine availability is also dependent on the activity of nucleoside transporters (NTs). The interplay between NTs and adenosine receptors’ activities are debated and a particular attention is given to the paramount importance of the disruption of this interplay in vascular pathophysiology, namely in hypertension., The integration of important functional aspects of individual adenosine receptor pharmacology (such as in vasoconstriction/vasodilation) and morphological features (within the three vascular layers) in vessels will be discussed, hopefully clarifying the importance of adenosine receptors/NTs for modulating peripheral mesenteric vascular resistance. In recent years, an increase interest in purine physiology/pharmacology has led to the development of new ligands for adenosine receptors. Some of them have been patented as having promising therapeutic activities and some have been chosen to undergo on clinical trials. Increased levels of endogenous adenosine near a specific subtype can lead to its activation, constituting an indirect receptor targeting approach either by inhibition of NT or, alternatively, by increasing the activity of enzymes responsible for ATP breakdown. These findings highlight the putative role of adenosinergic players as attractive therapeutic targets for cardiovascular pathologies, namely hypertension, heart failure or stroke. Nevertheless, several aspects are still to be explored, creating new challenges to be addressed in future studies, particularly the development of strategies able to circumvent the predicted side effects of these therapies.
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Kazemi MH, Raoofi Mohseni S, Hojjat-Farsangi M, Anvari E, Ghalamfarsa G, Mohammadi H, Jadidi-Niaragh F. Adenosine and adenosine receptors in the immunopathogenesis and treatment of cancer. J Cell Physiol 2017; 233:2032-2057. [DOI: 10.1002/jcp.25873] [Citation(s) in RCA: 97] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2017] [Accepted: 02/21/2017] [Indexed: 12/18/2022]
Affiliation(s)
- Mohammad H. Kazemi
- Student Research Committee, Department of Immunology, School of Medicine; Iran University of Medical Sciences (IUMS); Tehran Iran
- Immunology Research Center; Tabriz University of Medical Sciences; Tabriz Iran
| | - Sahar Raoofi Mohseni
- Department of Immunology, School of Public Health; Tehran University of Medical Sciences; Tehran Iran
| | - Mohammad Hojjat-Farsangi
- Department of Oncology-Pathology, Immune and Gene Therapy Lab, Cancer Center Karolinska (CCK); Karolinska University Hospital Solna and Karolinska Institute; Stockholm Sweden
- Department of Immunology, School of Medicine; Bushehr University of Medical Sciences; Bushehr Iran
| | - Enayat Anvari
- Faculty of Medicine, Department of Physiology; Ilam University of Medical Sciences; Ilam Iran
| | - Ghasem Ghalamfarsa
- Medicinal Plants Research Center; Yasuj University of Medical Sciences; Yasuj Iran
| | - Hamed Mohammadi
- Immunology Research Center; Tabriz University of Medical Sciences; Tabriz Iran
- Faculty of Medicine, Department of Immunology; Tabriz University of Medical Sciences; Tabriz Iran
| | - Farhad Jadidi-Niaragh
- Immunology Research Center; Tabriz University of Medical Sciences; Tabriz Iran
- Department of Immunology, School of Public Health; Tehran University of Medical Sciences; Tehran Iran
- Faculty of Medicine, Department of Immunology; Tabriz University of Medical Sciences; Tabriz Iran
- Drug Applied Research Center; Tabriz University of Medical Sciences; Tabriz Iran
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Abstract
Adenosine is an endogenous nucleoside with multiple biological properties which plays a central role in the pathophysiology of tissue ischemia. Adenosine signals an imbalance between oxygen demand and supply, and it initiates responses to redress such a discrepancy. Besides its vasodilating properties, adenosine possesses anti-platelet and anti-neutrophil activities and provides cytoprotection. Adenosine is presumably the main mediator of the preconditioning phenomenon. During ischemia of the lower limbs, adenosine plays a physiological role by inducing vasodilatation and by preventing microcirculatory failure. Exercise training prolongs claudication distance possibly by inducing pulse increases of adenosine and consequently skeletal muscle preconditioning. Moreover, the adenosine increase which follows the administration of some drugs, such as buflomedil and propionylcarnitine, opens new perspectives in the management of leg ischemia. In fact, the concept arises of an ischemic (exercise-dependent) or pharmacologic preconditioning in the treatment of patients with claudication.
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Affiliation(s)
- F Laghi Pasini
- Institute of Medical Semeiotics, University of Siena, Siena, Italy, Section of Clinical Immunology, University of Siena, Siena, Italy
| | - PL Capecchi
- Institute of Medical Semeiotics, University of Siena, Siena, Italy, Section of Clinical Immunology, University of Siena, Siena, Italy
| | - T Di Perri
- Institute of Medical Semeiotics, University of Siena, Siena, Italy
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Sun Y, Huang P. Adenosine A2B Receptor: From Cell Biology to Human Diseases. Front Chem 2016; 4:37. [PMID: 27606311 PMCID: PMC4995213 DOI: 10.3389/fchem.2016.00037] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 08/11/2016] [Indexed: 12/26/2022] Open
Abstract
Extracellular adenosine is a ubiquitous signaling molecule that modulates a wide array of biological processes. Recently, significant advances have been made in our understanding of A2B adenosine receptor (A2BAR). In this review, we first summarize some of the general characteristics of A2BAR, and then we describe the multiple binding partners of the receptor, such as newly identified α-actinin-1 and p105, and discuss how these associated proteins could modulate A2BAR's functions, including certain seemingly paradoxical functions of the receptor. Growing evidence indicates a critical role of A2BAR in cancer, renal disease, and diabetes, in addition to its importance in the regulation of vascular diseases, and lung disease. Here, we also discuss the role of A2BAR in cancer, renal disease, and diabetes and the potential of the receptor as a target for treating these three diseases.
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Affiliation(s)
- Ying Sun
- Department of Biology, South University of Science and Technology of ChinaShenzhen, China; Shenzhen Key Laboratory of Cell Microenvironment, South University of Science and Technology of ChinaShenzhen, China
| | - Pingbo Huang
- Division of Life Science, Hong Kong University of Science and TechnologyHong Kong, China; Division of Biomedical Engineering, Hong Kong University of Science and TechnologyHong Kong, China; State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and TechnologyHong Kong, China
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11
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Ferrari D, Gambari R, Idzko M, Müller T, Albanesi C, Pastore S, La Manna G, Robson SC, Cronstein B. Purinergic signaling in scarring. FASEB J 2016; 30:3-12. [PMID: 26333425 PMCID: PMC4684510 DOI: 10.1096/fj.15-274563] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Accepted: 08/17/2015] [Indexed: 12/23/2022]
Abstract
Adenosine (ADO) and nucleotides such as ATP, ADP, and uridine 5'-triphosphate (UTP), among others, may serve as extracellular signaling molecules. These mediators activate specific cell-surface receptors-namely, purinergic 1 and 2 (P1 and P2)-to modulate crucial pathophysiological responses. Regulation of this process is maintained by nucleoside and nucleotide transporters, as well as the ectonucleotidases ectonucleoside triphosphate diphosphohydrolase [ENTPD; cluster of differentiation (CD)39] and ecto-5'-nucleotidase (5'-NT; CD73), among others. Cells involved in tissue repair, healing, and scarring respond to both ADO and ATP. Our recent investigations have shown that modulation of purinergic signaling regulates matrix deposition during tissue repair and fibrosis in several organs. Cells release adenine nucleotides into the extracellular space, where these mediators are converted by CD39 and CD73 into ADO, which is anti-inflammatory in the short term but may also promote dermal, heart, liver, and lung fibrosis with repetitive signaling under defined circumstances. Extracellular ATP stimulates cardiac fibroblast proliferation, lung inflammation, and fibrosis. P2Y2 (UTP/ATP) and P2Y6 [ADP/UTP/uridine 5'-diphosphate (UDP)] have been shown to have profibrotic effects, as well. Modulation of purinergic signaling represents a novel approach to preventing or diminishing fibrosis. We provide an overview of the current understanding of purinergic signaling in scarring and discuss its potential to prevent or decrease fibrosis.
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Affiliation(s)
- Davide Ferrari
- *Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy; Department of Pneumology, University of Freiburg, Freiburg, Germany; Laboratory of Immunology and Laboratory of Tissue Engineering and Cutaneous Physiopathology, Istituto Dermopatico dell'Immacolata, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Rome, Italy; Department of Specialized, Diagnostic, and Experimental Medicine, University of Bologna, Bologna, Italy; Department of Medicine, Beth Israel Deaconess Medical Center, Harvard University, Boston, Massachusetts, USA; and Department of Medicine, New York University, New York, New York, USA
| | - Roberto Gambari
- *Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy; Department of Pneumology, University of Freiburg, Freiburg, Germany; Laboratory of Immunology and Laboratory of Tissue Engineering and Cutaneous Physiopathology, Istituto Dermopatico dell'Immacolata, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Rome, Italy; Department of Specialized, Diagnostic, and Experimental Medicine, University of Bologna, Bologna, Italy; Department of Medicine, Beth Israel Deaconess Medical Center, Harvard University, Boston, Massachusetts, USA; and Department of Medicine, New York University, New York, New York, USA
| | - Marco Idzko
- *Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy; Department of Pneumology, University of Freiburg, Freiburg, Germany; Laboratory of Immunology and Laboratory of Tissue Engineering and Cutaneous Physiopathology, Istituto Dermopatico dell'Immacolata, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Rome, Italy; Department of Specialized, Diagnostic, and Experimental Medicine, University of Bologna, Bologna, Italy; Department of Medicine, Beth Israel Deaconess Medical Center, Harvard University, Boston, Massachusetts, USA; and Department of Medicine, New York University, New York, New York, USA
| | - Tobias Müller
- *Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy; Department of Pneumology, University of Freiburg, Freiburg, Germany; Laboratory of Immunology and Laboratory of Tissue Engineering and Cutaneous Physiopathology, Istituto Dermopatico dell'Immacolata, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Rome, Italy; Department of Specialized, Diagnostic, and Experimental Medicine, University of Bologna, Bologna, Italy; Department of Medicine, Beth Israel Deaconess Medical Center, Harvard University, Boston, Massachusetts, USA; and Department of Medicine, New York University, New York, New York, USA
| | - Cristina Albanesi
- *Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy; Department of Pneumology, University of Freiburg, Freiburg, Germany; Laboratory of Immunology and Laboratory of Tissue Engineering and Cutaneous Physiopathology, Istituto Dermopatico dell'Immacolata, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Rome, Italy; Department of Specialized, Diagnostic, and Experimental Medicine, University of Bologna, Bologna, Italy; Department of Medicine, Beth Israel Deaconess Medical Center, Harvard University, Boston, Massachusetts, USA; and Department of Medicine, New York University, New York, New York, USA
| | - Saveria Pastore
- *Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy; Department of Pneumology, University of Freiburg, Freiburg, Germany; Laboratory of Immunology and Laboratory of Tissue Engineering and Cutaneous Physiopathology, Istituto Dermopatico dell'Immacolata, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Rome, Italy; Department of Specialized, Diagnostic, and Experimental Medicine, University of Bologna, Bologna, Italy; Department of Medicine, Beth Israel Deaconess Medical Center, Harvard University, Boston, Massachusetts, USA; and Department of Medicine, New York University, New York, New York, USA
| | - Gaetano La Manna
- *Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy; Department of Pneumology, University of Freiburg, Freiburg, Germany; Laboratory of Immunology and Laboratory of Tissue Engineering and Cutaneous Physiopathology, Istituto Dermopatico dell'Immacolata, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Rome, Italy; Department of Specialized, Diagnostic, and Experimental Medicine, University of Bologna, Bologna, Italy; Department of Medicine, Beth Israel Deaconess Medical Center, Harvard University, Boston, Massachusetts, USA; and Department of Medicine, New York University, New York, New York, USA
| | - Simon C Robson
- *Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy; Department of Pneumology, University of Freiburg, Freiburg, Germany; Laboratory of Immunology and Laboratory of Tissue Engineering and Cutaneous Physiopathology, Istituto Dermopatico dell'Immacolata, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Rome, Italy; Department of Specialized, Diagnostic, and Experimental Medicine, University of Bologna, Bologna, Italy; Department of Medicine, Beth Israel Deaconess Medical Center, Harvard University, Boston, Massachusetts, USA; and Department of Medicine, New York University, New York, New York, USA
| | - Bruce Cronstein
- *Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy; Department of Pneumology, University of Freiburg, Freiburg, Germany; Laboratory of Immunology and Laboratory of Tissue Engineering and Cutaneous Physiopathology, Istituto Dermopatico dell'Immacolata, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Rome, Italy; Department of Specialized, Diagnostic, and Experimental Medicine, University of Bologna, Bologna, Italy; Department of Medicine, Beth Israel Deaconess Medical Center, Harvard University, Boston, Massachusetts, USA; and Department of Medicine, New York University, New York, New York, USA
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Dubey RK, Fingerle J, Gillespie DG, Mi Z, Rosselli M, Imthurn B, Jackson EK. Adenosine Attenuates Human Coronary Artery Smooth Muscle Cell Proliferation by Inhibiting Multiple Signaling Pathways That Converge on Cyclin D. Hypertension 2015; 66:1207-19. [PMID: 26416848 PMCID: PMC4644125 DOI: 10.1161/hypertensionaha.115.05912] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Accepted: 09/07/2015] [Indexed: 01/01/2023]
Abstract
The goal of this study was to determine whether and how adenosine affects the proliferation of human coronary artery smooth muscle cells (HCASMCs). In HCASMCs, 2-chloroadenosine (stable adenosine analogue), but not N(6)-cyclopentyladenosine, CGS21680, or N(6)-(3-iodobenzyl)-adenosine-5'-N-methyluronamide, inhibited HCASMC proliferation (A2B receptor profile). 2-Chloroadenosine increased cAMP, reduced phosphorylation (activation) of ERK and Akt (protein kinases known to increase cyclin D expression and activity, respectively), and reduced levels of cyclin D1 (cyclin that promotes cell-cycle progression in G1). Moreover, 2-chloroadenosine inhibited expression of S-phase kinase-associated protein-2 (Skp2; promotes proteolysis of p27(Kip1)) and upregulated levels of p27(Kip1) (cell-cycle regulator that impairs cyclin D function). 2-Chloroadenosine also inhibited signaling downstream of cyclin D, including hyperphosphorylation of retinoblastoma protein and expression of cyclin A (S phase cyclin). Knockdown of A2B receptors prevented the effects of 2-chloroadenosine on ERK1/2, Akt, Skp2, p27(Kip1), cyclin D1, cyclin A, and proliferation. Likewise, inhibition of adenylyl cyclase and protein kinase A abrogated 2-chloroadenosine's inhibitory effects on Skp2 and stimulatory effects on p27(Kip1) and rescued HCASMCs from 2-chloroadenosine-mediated inhibition. Knockdown of p27(Kip1) also reversed the inhibitory effects of 2-chloroadenosine on HCASMC proliferation. In vivo, peri-arterial (rat carotid artery) 2-chloroadenosine (20 μmol/L for 7 days) downregulated vascular expression of Skp2, upregulated vascular expression of p27(Kip1), and reduced neointima hyperplasia by 71% (P<0.05; neointimal thickness: control, 37 424±18 371 pixels; treated, 10 352±2824 pixels). In conclusion, the adenosine/A2B receptor/cAMP/protein kinase A axis inhibits HCASMC proliferation by blocking multiple signaling pathways (ERK1/2, Akt, and Skp2) that converge at cyclin D, a key G1 cyclin that controls cell-cycle progression.
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Affiliation(s)
- Raghvendra K Dubey
- From the Department of Reproductive Endocrinology, University Hospital Zurich, Switzerland (R.K.D., M.R., B.I.); Zurich Center for Integrative Human Physiology (ZIHP), University of Zurich, Switzerland (R.K.D.); Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine (D.G.G., Z.M., E.K.J.); and Preclinical Pharma Research 68/209, F. Hoffmann-La-Roche, Basel, Switzerland (J.F.).
| | - Jürgen Fingerle
- From the Department of Reproductive Endocrinology, University Hospital Zurich, Switzerland (R.K.D., M.R., B.I.); Zurich Center for Integrative Human Physiology (ZIHP), University of Zurich, Switzerland (R.K.D.); Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine (D.G.G., Z.M., E.K.J.); and Preclinical Pharma Research 68/209, F. Hoffmann-La-Roche, Basel, Switzerland (J.F.)
| | - Delbert G Gillespie
- From the Department of Reproductive Endocrinology, University Hospital Zurich, Switzerland (R.K.D., M.R., B.I.); Zurich Center for Integrative Human Physiology (ZIHP), University of Zurich, Switzerland (R.K.D.); Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine (D.G.G., Z.M., E.K.J.); and Preclinical Pharma Research 68/209, F. Hoffmann-La-Roche, Basel, Switzerland (J.F.)
| | - Zaichuan Mi
- From the Department of Reproductive Endocrinology, University Hospital Zurich, Switzerland (R.K.D., M.R., B.I.); Zurich Center for Integrative Human Physiology (ZIHP), University of Zurich, Switzerland (R.K.D.); Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine (D.G.G., Z.M., E.K.J.); and Preclinical Pharma Research 68/209, F. Hoffmann-La-Roche, Basel, Switzerland (J.F.)
| | - Marinella Rosselli
- From the Department of Reproductive Endocrinology, University Hospital Zurich, Switzerland (R.K.D., M.R., B.I.); Zurich Center for Integrative Human Physiology (ZIHP), University of Zurich, Switzerland (R.K.D.); Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine (D.G.G., Z.M., E.K.J.); and Preclinical Pharma Research 68/209, F. Hoffmann-La-Roche, Basel, Switzerland (J.F.)
| | - Bruno Imthurn
- From the Department of Reproductive Endocrinology, University Hospital Zurich, Switzerland (R.K.D., M.R., B.I.); Zurich Center for Integrative Human Physiology (ZIHP), University of Zurich, Switzerland (R.K.D.); Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine (D.G.G., Z.M., E.K.J.); and Preclinical Pharma Research 68/209, F. Hoffmann-La-Roche, Basel, Switzerland (J.F.)
| | - Edwin K Jackson
- From the Department of Reproductive Endocrinology, University Hospital Zurich, Switzerland (R.K.D., M.R., B.I.); Zurich Center for Integrative Human Physiology (ZIHP), University of Zurich, Switzerland (R.K.D.); Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine (D.G.G., Z.M., E.K.J.); and Preclinical Pharma Research 68/209, F. Hoffmann-La-Roche, Basel, Switzerland (J.F.)
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Abstract
There are nineteen different receptor proteins for adenosine, adenine and uridine nucleotides, and nucleotide sugars, belonging to three families of G protein-coupled adenosine and P2Y receptors, and ionotropic P2X receptors. The majority are functionally expressed in blood vessels, as purinergic receptors in perivascular nerves, smooth muscle and endothelial cells, and roles in regulation of vascular contractility, immune function and growth have been identified. The endogenous ligands for purine receptors, ATP, ADP, UTP, UDP and adenosine, can be released from different cell types within the vasculature, as well as from circulating blood cells, including erythrocytes and platelets. Many purine receptors can be activated by two or more of the endogenous ligands. Further complexity arises because of interconversion between ligands, notably adenosine formation from the metabolism of ATP, leading to complex integrated responses through activation of different subtypes of purine receptors. The enzymes responsible for this conversion, ectonucleotidases, are present on the surface of smooth muscle and endothelial cells, and may be coreleased with neurotransmitters from nerves. What selectivity there is for the actions of purines/pyrimidines comes from differential expression of their receptors within the vasculature. P2X1 receptors mediate the vasocontractile actions of ATP released as a neurotransmitter with noradrenaline (NA) from sympathetic perivascular nerves, and are located on the vascular smooth muscle adjacent to the nerve varicosities, the sites of neurotransmitter release. The relative contribution of ATP and NA as functional cotransmitters varies with species, type and size of blood vessel, neuronal firing pattern, the tone/pressure of the blood vessel, and in ageing and disease. ATP is also a neurotransmitter in non-adrenergic non-cholinergic perivascular nerves and mediates vasorelaxation via smooth muscle P2Y-like receptors. ATP and adenosine can act as neuromodulators, with the most robust evidence being for prejunctional inhibition of neurotransmission via A1 adenosine receptors, but also prejunctional excitation and inhibition of neurotransmission via P2X and P2Y receptors, respectively. P2Y2, P2Y4 and P2Y6 receptors expressed on the vascular smooth muscle are coupled to vasocontraction, and may have a role in pathophysiological conditions, when purines are released from damaged cells, or when there is damage to the protective barrier that is the endothelium. Adenosine is released during hypoxia to increase blood flow via vasodilator A2A and A2B receptors expressed on the endothelium and smooth muscle. ATP is released from endothelial cells during hypoxia and shear stress and can act at P2Y and P2X4 receptors expressed on the endothelium to increase local blood flow. Activation of endothelial purine receptors leads to the release of nitric oxide, hyperpolarising factors and prostacyclin, which inhibits platelet aggregation and thus ensures patent blood flow. Vascular purine receptors also regulate endothelial and smooth muscle growth, and inflammation, and thus are involved in the underlying processes of a number of cardiovascular diseases.
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Affiliation(s)
- Vera Ralevic
- School of Life Sciences, Queen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, United Kingdom.
| | - William R Dunn
- School of Life Sciences, Queen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, United Kingdom
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Antonioli L, Blandizzi C, Csóka B, Pacher P, Haskó G. Adenosine signalling in diabetes mellitus--pathophysiology and therapeutic considerations. Nat Rev Endocrinol 2015; 11:228-41. [PMID: 25687993 DOI: 10.1038/nrendo.2015.10] [Citation(s) in RCA: 124] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Adenosine is a key extracellular signalling molecule that regulates several aspects of tissue function by activating four G-protein-coupled receptors, A1, A2A, A2B and A1 adenosine receptors. Accumulating evidence highlights a critical role for the adenosine system in the regulation of glucose homeostasis and the pathophysiology of type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM). Although adenosine signalling is known to affect insulin secretion, new data indicate that adenosine signalling also contributes to the regulation of β-cell homeostasis and activity by controlling the proliferation and regeneration of these cells as well as the survival of β cells in inflammatory microenvironments. Furthermore, adenosine is emerging as a major regulator of insulin responsiveness by controlling insulin signalling in adipose tissue, muscle and liver; adenosine also indirectly mediates effects on inflammatory and/or immune cells in these tissues. This Review critically discusses the role of the adenosine-adenosine receptor system in regulating both the onset and progression of T1DM and T2DM, and the potential of pharmacological manipulation of the adenosinergic system as an approach to manage T1DM, T2DM and their associated complications.
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Affiliation(s)
- Luca Antonioli
- Department of Clinical and Experimental Medicine, University of Pisa, Via Roma 55, 56126 Pisa, Italy
| | - Corrado Blandizzi
- Department of Clinical and Experimental Medicine, University of Pisa, Via Roma 55, 56126 Pisa, Italy
| | - Balázs Csóka
- Department of Surgery and Center for Immunity and Inflammation, Rutgers-New Jersey Medical School, 185 South Orange Avenue, University Heights, Newark, NJ 07103, USA
| | - Pál Pacher
- Section on Oxidative Stress Tissue Injury, Laboratories of Physiological Studies, NIH/NIAAA, 5625 Fishers Lane, Bethesda, MD 20892, USA
| | - György Haskó
- Department of Surgery and Center for Immunity and Inflammation, Rutgers-New Jersey Medical School, 185 South Orange Avenue, University Heights, Newark, NJ 07103, USA
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Helenius MH, Vattulainen S, Orcholski M, Aho J, Komulainen A, Taimen P, Wang L, de Jesus Perez VA, Koskenvuo JW, Alastalo TP. Suppression of endothelial CD39/ENTPD1 is associated with pulmonary vascular remodeling in pulmonary arterial hypertension. Am J Physiol Lung Cell Mol Physiol 2015; 308:L1046-57. [PMID: 25820525 DOI: 10.1152/ajplung.00340.2014] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Accepted: 03/24/2015] [Indexed: 11/22/2022] Open
Abstract
Endothelial cell (EC) dysfunction plays a role in the pathobiology of occlusive vasculopathy in pulmonary arterial hypertension (PAH). Purinergic signaling pathways, which consist of extracellular nucleotide and nucleoside-mediated cell signaling through specific receptors, are known to be important regulators of vascular tone and remodeling. Therefore, we hypothesized that abnormalities in the vascular purinergic microenvironment are associated with PAH. Enzymatic clearance is crucial to terminate unnecessary cell activation; one of the most abundantly expressed enzymes on the EC surface is E-NTPDase1/CD39, which hydrolyzes ATP and ADP to AMP. we used histological samples from patients and healthy donors, radioisotope-labeled substrates to measure ectoenzyme activity, and a variety of in vitro approaches to study the role of CD39 in PAH. Immunohistochemistry on human idiopathic PAH (IPAH) patients' lungs demonstrated that CD39 was significantly downregulated in the endothelium of diseased small arteries. Similarly, CD39 expression and activity were decreased in cultured pulmonary ECs from IPAH patients. Suppression of CD39 in vitro resulted in EC phenotypic switch that gave rise to apoptosis-resistant pulmonary arterial endothelial cells and promoted a microenvironment that induced vascular smooth muscle cell migration. we also identified that the ATP receptor P2Y11 is essential for ATP-mediated EC survival. Furthermore, we report that apelin, a known regulator of pulmonary vascular homeostasis, can potentiate the activity of CD39 both in vitro and in vivo. we conclude that sustained attenuation of CD39 activity through ATP accumulation is tightly linked to vascular dysfunction and remodeling in PAH and could represent a novel target for therapy.
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Affiliation(s)
- Mikko H Helenius
- Children's Hospital Helsinki, Pediatric Cardiology, University of Helsinki and Helsinki University Central Hospital, Helsinki, Finland
| | - Sanna Vattulainen
- Children's Hospital Helsinki, Pediatric Cardiology, University of Helsinki and Helsinki University Central Hospital, Helsinki, Finland
| | - Mark Orcholski
- Division of Pulmonary and Critical Care Medicine, Stanford University, Stanford, California
| | - Joonas Aho
- Research Centre of Applied and Preventive Cardiovascular Medicine, University of Turku, Turku, Finland
| | - Anne Komulainen
- Children's Hospital Helsinki, Pediatric Cardiology, University of Helsinki and Helsinki University Central Hospital, Helsinki, Finland
| | - Pekka Taimen
- Department of Pathology, University of Turku and Turku University Hospital, Turku, Finland; and
| | - Lingli Wang
- Division of Pulmonary and Critical Care Medicine, Stanford University, Stanford, California
| | | | - Juha W Koskenvuo
- Research Centre of Applied and Preventive Cardiovascular Medicine, University of Turku, Turku, Finland; Department of Clinical Physiology and Nuclear Medicine, Helsinki University Central Hospital, Helsinki, Finland
| | - Tero-Pekka Alastalo
- Children's Hospital Helsinki, Pediatric Cardiology, University of Helsinki and Helsinki University Central Hospital, Helsinki, Finland;
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Roche PL, Filomeno KL, Bagchi RA, Czubryt MP. Intracellular Signaling of Cardiac Fibroblasts. Compr Physiol 2015; 5:721-60. [DOI: 10.1002/cphy.c140044] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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17
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Burnstock G, Ralevic V. Purinergic signaling and blood vessels in health and disease. Pharmacol Rev 2013; 66:102-92. [PMID: 24335194 DOI: 10.1124/pr.113.008029] [Citation(s) in RCA: 219] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Purinergic signaling plays important roles in control of vascular tone and remodeling. There is dual control of vascular tone by ATP released as a cotransmitter with noradrenaline from perivascular sympathetic nerves to cause vasoconstriction via P2X1 receptors, whereas ATP released from endothelial cells in response to changes in blood flow (producing shear stress) or hypoxia acts on P2X and P2Y receptors on endothelial cells to produce nitric oxide and endothelium-derived hyperpolarizing factor, which dilates vessels. ATP is also released from sensory-motor nerves during antidromic reflex activity to produce relaxation of some blood vessels. In this review, we stress the differences in neural and endothelial factors in purinergic control of different blood vessels. The long-term (trophic) actions of purine and pyrimidine nucleosides and nucleotides in promoting migration and proliferation of both vascular smooth muscle and endothelial cells via P1 and P2Y receptors during angiogenesis and vessel remodeling during restenosis after angioplasty are described. The pathophysiology of blood vessels and therapeutic potential of purinergic agents in diseases, including hypertension, atherosclerosis, ischemia, thrombosis and stroke, diabetes, and migraine, is discussed.
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Affiliation(s)
- Geoffrey Burnstock
- Autonomic Neuroscience Centre, University College Medical School, Rowland Hill Street, London NW3 2PF, UK; and Department of Pharmacology, The University of Melbourne, Australia.
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18
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Hinze AV, Mayer P, Harst A, von Kügelgen I. P2X1 receptor-mediated inhibition of the proliferation of human coronary smooth muscle cells involving the transcription factor NR4A1. Purinergic Signal 2013; 9:677-86. [PMID: 23873636 PMCID: PMC3889386 DOI: 10.1007/s11302-013-9380-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2013] [Accepted: 07/03/2013] [Indexed: 01/28/2023] Open
Abstract
Adenine nucleotides acting at P2X1 receptors are potent vasoconstrictors. Recently, we demonstrated that activation of adenosine A2B receptors on human coronary smooth muscle cells inhibits cell proliferation by the induction of the nuclear receptor subfamily 4, group A, member 1 (NR4A1; alternative notation Nur77). In the present study, we searched for long-term effects mediated by P2X1 receptors by analyzing receptor-mediated changes in cell proliferation and in the expression of NR4A1. Cultured human coronary smooth muscle cells were treated with selective receptor ligands. Effects on proliferation were determined by counting cells and measuring changes in impedance. The induction of transcription factors was assessed by qPCR. The P2X receptor agonist α,β-methylene-ATP and its analog β,γ-methylene-ATP inhibited cell proliferation by about 50 % after 5 days in culture with half-maximal concentrations of 0.3 and 0.08 μM, respectively. The effects were abolished or markedly attenuated by the P2X1 receptor antagonist NF449 (carbonylbis-imino-benzene-triylbis-(carbonylimino)tetrakis-benzene-1,3-disulfonic acid; 100 nM and 1 μM). α,β-methylene-ATP and β,γ-methylene-ATP applied for 30 min to 4 h increased the expression of NR4A1; NF449 blocked or attenuated this effect. Small interfering RNA directed against NR4A1 diminished the antiproliferative effects of α,β-methylene-ATP and β,γ-methylene-ATP. α,β-methylene-ATP (0.1 to 30 μM) decreased migration of cultured human coronary smooth muscle cells in a chamber measuring changes in impedance; NF449 blocked the effect. In conclusion, our results demonstrate for the first time that adenine nucleotides acting at P2X1 receptors inhibit the proliferation of human coronary smooth muscle cells via the induction of the early gene NR4A1.
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Affiliation(s)
- Annette Viktoria Hinze
- />Federal Institute for Drugs and Medical Devices, Kurt-Georg-Kiesinger-Allee 3, 53175 Bonn, Germany
- />Department of Pharmacology and Toxicology, University of Bonn, 53105 Bonn, Germany
- />Department of Clinical Chemistry and Clinical Pharmacology, University of Bonn, 53105 Bonn, Germany
| | - Peter Mayer
- />Federal Institute for Drugs and Medical Devices, Kurt-Georg-Kiesinger-Allee 3, 53175 Bonn, Germany
| | - Anja Harst
- />Federal Institute for Drugs and Medical Devices, Kurt-Georg-Kiesinger-Allee 3, 53175 Bonn, Germany
| | - Ivar von Kügelgen
- />Department of Pharmacology and Toxicology, University of Bonn, 53105 Bonn, Germany
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Paeoniflorin inhibits pulmonary artery smooth muscle cells proliferation via upregulating A2B adenosine receptor in rat. PLoS One 2013; 8:e69141. [PMID: 23935939 PMCID: PMC3728310 DOI: 10.1371/journal.pone.0069141] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Accepted: 06/12/2013] [Indexed: 11/22/2022] Open
Abstract
Paeoniflorin (PF), which is the main active ingredient in the root of Paeonia Radix, has many pharmacological effects. Here, we investigated the effect of PF on rat pulmonary artery smooth muscle cells (PASMCs) under hypoxic conditions and explored the mechanisms of the effects. The anti-proliferative effect of PF increased in a dose dependent manner. At the highest dose (20 μmol/L), the anti-proliferative effect of PF peaked at 24 h after administration. However, the selective A2B adenosine receptor (A2BAR) antagonist MRS1754 abolished it. PF increased A2BAR mRNA levels from 0.0763±0.0067 of β-actin mRNA levels (hypoxia group) to 0.1190±0.0139 (P<0.05) measured by Real Time Reverse Transcription-Polymerase Chain Reaction. A2BAR protein expression measured by Western Blot was also increased. PF inhibited the proliferation of PASMCs by blocking cell cycle progression in the S phase. These data indicated that activation of A2BAR might be involved in the anti-proliferative effect of PF on PASMCs under hypoxic conditions. The results suggested that a new mechanism of PF could be relevant to the management of clinical hypoxic pulmonary hypertension.
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Jackson EK, Gillespie DG. Regulation of Cell Proliferation by the Guanosine-Adenosine Mechanism: Role of Adenosine Receptors. Physiol Rep 2013; 1:e00024. [PMID: 23956837 PMCID: PMC3743120 DOI: 10.1002/phy2.24] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
A recent study (American Journal of Physiology – Cell Physiology 304:C406–C421, 2013) suggests that extracellular guanosine increases extracellular adenosine by modifying the disposition of extracellular adenosine (“guanosine–adenosine mechanism”) and that the guanosine–adenosine mechanism is not mediated by classical adenosine transport systems (SLC28 and SLC29 families) nor by classical adenosine-metabolizing enzymes. The present investigation had two aims (1) to test the hypothesis that the “guanosine–adenosine mechanism” affects cell proliferation; and (2) to determine whether the transporters SLC19A1, SLC19A2, SLC19A3, or SLC22A2 (known to carrier guanosine analogs) might be responsible for the guanosine–adenosine mechanism. In the absence of added adenosine, guanosine had little effect on the proliferation of coronary artery vascular smooth muscle cells (vascular conduit cells) or preglomerular vascular smooth muscle cells (vascular resistance cells). However, in the presence of added adenosine (3 or 10 μmol/L), guanosine (10–100 μmol/L) decreased proliferation of both cell types, thus resulting in a highly significant (P < 0.000001) interaction between guanosine and adenosine on cell proliferation. The guanosine–adenosine interaction on cell proliferation was abolished by 1,3-dipropyl-8-(p-sulfophenyl)xanthine (adenosine receptor antagonist). Guanosine (30 μmol/L) increased extracellular levels of adenosine when adenosine (3 μmol/L) was added to the medium. This effect was not reproduced by high concentrations of methotrexate (100 μmol/L), thiamine (1000 μmol/L), chloroquine (1000 μmol/L), or acyclovir (10,000 μmol/L), archetypal substrates for SLC19A1, SLC19A2, SLC19A3, and SLC22A2, respectively; and guanosine still increased adenosine levels in the presence of these compounds. In conclusion, the guanosine–adenosine mechanism affects cell proliferation and is not mediated by SLC19A1, SLC19A2, SLC19A3, or SLC22A2.
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Affiliation(s)
- Edwin K Jackson
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15219
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21
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Ahmad A, Schaack JB, White CW, Ahmad S. Adenosine A2A receptor-dependent proliferation of pulmonary endothelial cells is mediated through calcium mobilization, PI3-kinase and ERK1/2 pathways. Biochem Biophys Res Commun 2013; 434:566-71. [PMID: 23583199 DOI: 10.1016/j.bbrc.2013.03.115] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Accepted: 03/26/2013] [Indexed: 12/13/2022]
Abstract
Hypoxia and HIF-2α-dependent A2A receptor expression and activation increase proliferation of human lung microvascular endothelial cells (HLMVECs). This study was undertaken to investigate the signaling mechanisms that mediate the proliferative effects of A2A receptor. A2A receptor-mediated proliferation of HLMVECs was inhibited by intracellular calcium chelation, and by specific inhibitors of ERK1/2 and PI3-kinase (PI3K). The adenosine A2A receptor agonist CGS21680 caused intracellular calcium mobilization in controls and, to a greater extent, in A2A receptor-overexpressing HLMVECs. Adenoviral-mediated A2A receptor overexpression as well as receptor activation by CGS21680 caused increased PI3K activity and Akt phosphorylation. Cells overexpressing A2A receptor also manifested enhanced ERK1/2 phosphorylation upon CGS21680 treatment. A2A receptor activation also caused enhanced cAMP production. Likewise, treatment with 8Br-cAMP increased PI3K activity. Hence A2A receptor-mediated cAMP production and PI3K and Akt phosphorylation are potential mediators of the A2A-mediated proliferative response of HLMVECs. Cytosolic calcium mobilization and ERK1/2 phosphorylation are other critical effectors of HLMVEC proliferation and growth. These studies underscore the importance of adenosine A2A receptor in activation of survival and proliferative pathways in pulmonary endothelial cells that are mediated through PI3K/Akt and ERK1/2 pathways.
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Affiliation(s)
- Aftab Ahmad
- Pediatric Airway Research Center, Department of Pediatrics, Aurora, CO 80045, USA.
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Adenosine A3 receptor-induced proliferation of primary human coronary smooth muscle cells involving the induction of early growth response genes. J Mol Cell Cardiol 2012; 53:639-45. [DOI: 10.1016/j.yjmcc.2012.08.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2012] [Revised: 08/03/2012] [Accepted: 08/04/2012] [Indexed: 11/22/2022]
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Abstract
Cardiovascular disease, a leading cause of death and morbidity, is regulated, among various factors, by inflammation. The level of the metabolite adenosine is augmented under stress, including inflammatory, hypoxic, or injurious events. Adenosine has been shown to affect various physiological and pathological processes, largely through 1 or more of its 4 types of receptors: the A1 and A3 adenylyl cyclase inhibitory receptors and the A2A and A2B adenylyl cyclase stimulatory receptors. This article focuses on reviewing common and distinct effects of the 2 A2-type adenosine receptors on vascular disease and the mechanisms involved. Understanding the pathogenesis of vascular disease mediated by these receptors is important to the development of therapeutics and to the prevention and management of disease.
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Affiliation(s)
- Hillary A. Johnston-Cox
- Departments of Medicine and Biochemistry, Whitaker Cardiovascular Institute, and Evans Center for Interdisciplinary Biomedical Research, Boston University School of Medicine, Boston, MA 02118
| | - Milka Koupenova
- Departments of Medicine and Biochemistry, Whitaker Cardiovascular Institute, and Evans Center for Interdisciplinary Biomedical Research, Boston University School of Medicine, Boston, MA 02118
| | - Katya Ravid
- Departments of Medicine and Biochemistry, Whitaker Cardiovascular Institute, and Evans Center for Interdisciplinary Biomedical Research, Boston University School of Medicine, Boston, MA 02118
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Jackson EK, Ren J, Gillespie DG. 2',3'-cAMP, 3'-AMP, and 2'-AMP inhibit human aortic and coronary vascular smooth muscle cell proliferation via A2B receptors. Am J Physiol Heart Circ Physiol 2011; 301:H391-401. [PMID: 21622827 DOI: 10.1152/ajpheart.00336.2011] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Rat vascular smooth muscle cells (VSMCs) from renal microvessels metabolize 2',3'-cAMP to 2'-AMP and 3'-AMP, and these AMPs are converted to adenosine that inhibits microvascular VSMC proliferation via A(2B) receptors. The goal of this study was to test whether this mechanism also exists in VSMCs from conduit arteries and whether it is similarly expressed in human vs. rat VSMCs. Incubation of rat and human aortic VSMCs with 2',3'-cAMP concentration-dependently increased levels of 2'-AMP and 3'-AMP in the medium, with a similar absolute increase in 2'-AMP vs. 3'-AMP. In contrast, in human coronary VSMCs, 2',3'-cAMP increased 2'-AMP levels yet had little effect on 3'-AMP levels. In all cell types, 2',3'-cAMP increased levels of adenosine, but not 5'-AMP, and 2',3'-AMP inhibited cell proliferation. Antagonism of A(2B) receptors (MRS-1754), but not A(1) (1,3-dipropyl-8-cyclopentylxanthine), A(2A) (SCH-58261), or A(3) (VUF-5574) receptors, attenuated the antiproliferative effects of 2',3'-cAMP. In all cell types, 2'-AMP, 3'-AMP, and 5'-AMP increased adenosine levels, and inhibition of ecto-5'-nucleotidase blocked this effect of 5'-AMP but not that of 2'-AMP nor 3'-AMP. Also, 2'-AMP, 3'-AMP, and 5'-AMP, like 2',3'-cAMP, exerted antiproliferative effects that were abolished by antagonism of A(2B) receptors with MRS-1754. In conclusion, VSMCs from conduit arteries metabolize 2',3'-cAMP to AMPs, which are metabolized to adenosine. In rat and human aortic VSMCs, both 2'-AMP and 3'-AMP are involved in this process, whereas, in human coronary VSMCs, 2',3'-cAMP is mainly converted to 2'-AMP. Because adenosine inhibits VSMC proliferation via A(2B) receptors, local vascular production of 2',3'-cAMP may protect conduit arteries from atherosclerosis.
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Affiliation(s)
- Edwin K Jackson
- Dept. of Pharmacology and Chemical Biology, Univ. of Pittsburgh School of Medicine, 100 Technology Drive, Rm. 514, Pittsburgh, PA 15219-3130, USA.
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Xiang HJ, Chai FL, Wang DS, Dou KF. Downregulation of the adenosine a2b receptor by RNA interference inhibits hepatocellular carcinoma cell growth. ISRN ONCOLOGY 2011; 2011:875684. [PMID: 22091434 PMCID: PMC3195956 DOI: 10.5402/2011/875684] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/25/2011] [Accepted: 03/08/2011] [Indexed: 11/23/2022]
Abstract
To investigate the biological effect of adenosine A2b receptor (A2bR) on the human hepatocellular carcinoma cell line HepG2, three A2bR siRNA constructs were transiently transfected into HepG2 cells. The results showed that A2bR siRNA reduced the levels of A2bR mRNA and protein. In order to further detect the function of A2bR, we established a stable hepatocellular carcinoma cell line (HepG2) expressing siRNA targeting the adenosine A2b receptor. Targeted RNAi significantly inhibited tumor cell growth in vitro, and flow cytometry (FCM) showed that significantly more cells expressing A2bR siRNA were in the G0/G1 phase compared to the untransfected group ((89.56% ± 3.15%) versus (56.19% ± 1.58%), P < 0.01). These results indicated that silencing the expression of adenosine A2b receptor in HepG2 cells can suppress cell growth effectively by blocking the cell cycle. Downregulation of adenosine A2b receptor gene expression with RNA interference could be a new approach to hepatocellular carcinoma therapy.
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Affiliation(s)
- Hong-Jun Xiang
- Department of Hepatobiliary Surgery, Lanzhou General Hospital, Lanzhou Military Area Command of Chinese People's Liberation Army, 98 XiaoXiHu Road, Lanzhou 730050, China
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Jackson EK, Gillespie DG, Dubey RK. 2'-AMP and 3'-AMP inhibit proliferation of preglomerular vascular smooth muscle cells and glomerular mesangial cells via A2B receptors. J Pharmacol Exp Ther 2011; 337:444-50. [PMID: 21270135 DOI: 10.1124/jpet.110.178137] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Studies show that kidneys produce 2',3'-cAMP, 2',3'-cAMP is exported and metabolized to 2'-AMP and 3'-AMP, 2'-AMP and 3'-AMP are metabolized to adenosine, 2',3'-cAMP inhibits proliferation of preglomerular vascular smooth muscle cells (PGVSMCs) and glomerular mesangial cells (GMCs), and A(2B) (not A(1), A(2A), or A(3)) adenosine receptors mediate part of the antiproliferative effects of 2',3'-cAMP. These findings suggest that extracellular 2',3'-cAMP attenuates proliferation of PGVSMCs and GMCs partly via conversion to corresponding AMPs, which are metabolized to adenosine that activates A(2B) receptors. This hypothesis predicts that extracellular 2'-AMP and 3'-AMP should exert A(2B) receptor-mediated antiproliferative effects. Therefore, we examined the antiproliferative effects (cell counts) of 2'-AMP and 3'-AMP. In PGVSMCs and GMCs, 2'-AMP and 3'-AMP exerted concentration-dependent antiproliferative effects. 3'-AMP was equipotent with and 2'-AMP was 3-fold less potent than 5'-AMP (prototypical adenosine precursor). In PGVSMCs, the effects of 2'-AMP and 3'-AMP were mimicked by adenosine, and 8-[4-[((4-cyanophenyl)carbamoylmethyl)oxy]phenyl]-1,3-di(n-propyl)xanthine (MRS-1754) (A(2B) receptor antagonist) equally blocked the antiproliferative effects of 2'-AMP, 3'-AMP, and adenosine but less effectively blocked the effects of 2',3'-cAMP. Similar results were obtained in GMCs except that MRS-1754 also incompletely blocked the effects of 3'-AMP. We conclude that in PGVSMCs, 2'-AMP and 3'-AMP are antiproliferative, the antiproliferative effects of 2'-AMP and 3'-AMP are mediated nearly entirely by adenosine/A(2B) receptors, and some of the antiproliferative effects of 2',3'-cAMP are independent of adenosine/A(2B) receptors. Similar conclusions apply to GMCs except that 3'-AMP also has actions independent of adenosine/A(2B) receptors. Because A(2B) receptors are renoprotective, 2'-AMP and 3'-AMP may provide renoprotection by generating adenosine that activates A(2B) receptors.
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Affiliation(s)
- Edwin K Jackson
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, 100 Technology Dr., Pittsburgh, PA 15219, USA.
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Mayer P, Hinze AV, Harst A, von Kügelgen I. A₂B receptors mediate the induction of early genes and inhibition of arterial smooth muscle cell proliferation via Epac. Cardiovasc Res 2010; 90:148-56. [PMID: 21109603 DOI: 10.1093/cvr/cvq371] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
AIMS Extracellular adenosine and adenine nucleotides play important roles in the regulation of the blood vessel tonus and platelet aggregation. Less is known about the effects of these extracellular signalling molecules on gene expression in vascular smooth muscle cells involved in long-term vascular effects. In the present study, we therefore searched for adenosine-induced changes in the expression of early genes in cultured human coronary artery smooth muscle cells (HCASMCs). METHODS AND RESULTS Whole-genome DNA array hybridization revealed that adenosine induced a set of early genes including the nuclear receptor subfamily 4, group A, member 1 (NR4A1/Nur77/TR3). The pattern of the effects of adenosine on gene expression resembles the change in expression induced by the direct activator of adenylate cyclase forskolin. Real-time reverse-transcriptase PCR confirmed that adenosine and its analogue N-ethyl-carboxamidoadenosine elicited a strong induction of NR4A1. These effects were markedly attenuated by A(2B) receptor antagonists including 8-[4-(4-benzylpiperazide-1-sulfonyl)phenyl]-1-propylxanthine (PSB-601) and were mimicked by a cyclic AMP (cAMP) analogue [8-(4-chlorophenylthio)-2'-O-methyl-cAMP, 8CPT] acting on the exchange protein activated by cAMP (Epac). Long-term experiments over 5 days showed that 2-chloroadenosine decreased cell proliferation in the presence of platelet-derived growth factor. This effect of 2-chloroadenosine was also attenuated by PSB-601 and mimicked by 8CPT. Treatment with small interfering RNA directed against NR4A1 attenuated the inhibitory effect of 8CPT on proliferation. CONCLUSIONS In summary, our results demonstrate the operation of adenosine A₂(B) receptors mediating an early induction of NR4A1 and a decrease in cell proliferation via the cAMP/Epac pathway in HCASMCs.
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Affiliation(s)
- Peter Mayer
- Federal Institute for Drugs and Medical Devices, Bonn, Germany.
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28
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Jackson EK, Ren J, Gillespie DG, Dubey RK. Extracellular 2,3-cyclic adenosine monophosphate is a potent inhibitor of preglomerular vascular smooth muscle cell and mesangial cell growth [corrected]. Hypertension 2010; 56:151-8. [PMID: 20516392 DOI: 10.1161/hypertensionaha.110.152454] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Recently we discovered that intact kidneys release into the extracellular compartment 2',3'-cAMP (a positional isomer of 3',5'-cAMP with unknown pharmacology) and metabolize 2',3'-cAMP to 2'-AMP, 3'-AMP, and adenosine. Because adenosine inhibits growth of vascular smooth muscle cells and mesangial cells, we tested the hypothesis that extracellular 2',3'-cAMP attenuates growth of preglomerular vascular smooth muscle and mesangial cells via production of adenosine. For comparison, all of the experiments were performed with both 2',3'-cAMP and 3',5'-cAMP. In study 1, 2',3'-cAMP, 3',5'-cAMP, 5'-AMP, 3'-AMP, or 2'-AMP was incubated with cells and purines measured in the medium by mass spectrometry. Both preglomerular vascular smooth muscle and mesangial cells metabolized 3',5'-cAMP to 5'-AMP and adenosine; 5'-AMP to adenosine; 2',3'-cAMP to 2'-AMP, 3'-AMP, and adenosine; and 2'-AMP and 3'-AMP to adenosine. 3-Isobutyl-1-methylxanthine (phosphodiesterase inhibitor) and 1,3-dipropyl-8-p-sulfophenylxanthine (ecto-phosphodiesterase inhibitor) blocked conversion of 3',5'-cAMP to 5'-AMP and adenosine, and alpha,beta-methylene-adenosine-5'-diphosphate (CD73 inhibitor) blocked conversion of 5'-AMP to adenosine. These enzyme inhibitors had little effect on metabolism of 2',3'-cAMP, 2'-AMP, or 3'-AMP. For study 2, 2',3'-cAMP and 3',5'-cAMP profoundly inhibited proliferation (thymidine incorporation and cell number) of both cell types, with 2',3'-cAMP more potent than 3',5'-cAMP. Antagonism of A(2B) receptors (MRS-1724), but not A(1) (1,3-dipropyl-8-cyclopentylxanthine), A(2A) (SCH-58261), or A(3) (VUF-5574) receptors, attenuated the growth inhibitory effects of 2',3'-cAMP and 3',5'-cAMP. Extracellular 2',3'-cAMP inhibits growth of preglomerular vascular smooth muscle and mesangial cells more profoundly than does 3',5'-cAMP. Although both cAMPs inhibit growth in part via conversion to adenosine followed by A(2B) receptor activation, their metabolism is mediated by different enzymes.
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Affiliation(s)
- Edwin K Jackson
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, 100 Technology Dr, Suite 450, Pittsburgh, PA 15219, USA.
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Aherne CM, Kewley EM, Eltzschig HK. The resurgence of A2B adenosine receptor signaling. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2010; 1808:1329-39. [PMID: 20546702 DOI: 10.1016/j.bbamem.2010.05.016] [Citation(s) in RCA: 107] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2010] [Revised: 05/16/2010] [Accepted: 05/17/2010] [Indexed: 01/05/2023]
Abstract
Since its discovery as a low-affinity adenosine receptor (AR), the A2B receptor (A2BAR), has proven enigmatic in its function. The previous discovery of the A2AAR, which shares many similarities with the A2BAR but demonstrates significantly greater affinity for its endogenous ligand, led to the original perception that the A2BAR was not of substantial physiologic relevance. In addition, lack of specific pharmacological agents targeting the A2BAR made its initial characterization challenging. However, the importance of this receptor was reconsidered when it was observed that the A2BAR is highly transcriptionally regulated by factors implicated in inflammatory hypoxia. Moreover, the notion that during ischemia or inflammation extracellular adenosine is dramatically elevated to levels sufficient for A2BAR activation, indicated that A2BAR signaling may be important to dampen inflammation particularly during tissue hypoxia. In addition, the recent advent of techniques for murine genetic manipulation along with development of pharmacological agents with enhanced A2BAR specificity has provided invaluable tools for focused studies on the explicit role of A2BAR signaling in different disease models. Currently, studies performed with combined genetic and pharmacological approaches have demonstrated that A2BAR signaling plays a tissue protective role in many models of acute diseases e.g. myocardial ischemia, or acute lung injury. These studies indicate that the A2BAR is expressed on a wide variety of cell types and exerts tissue/cell specific effects. This is an important consideration for future studies where tissue or cell type specific targeting of the A2BAR may be used as therapeutic approach.
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Affiliation(s)
- Carol M Aherne
- Department of Anesthesiology, University of Colorado, Aurora, CO, USA
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30
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Dubey RK, Rosselli M, Gillespie DG, Mi Z, Jackson EK. Extracellular 3',5'-cAMP-adenosine pathway inhibits glomerular mesangial cell growth. J Pharmacol Exp Ther 2010; 333:808-15. [PMID: 20194527 DOI: 10.1124/jpet.110.166371] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Abnormal growth of glomerular mesangial cells (GMCs) contributes to the pathophysiology of many types of nephropathy. Because adenosine is an autocrine/paracrine factor that potentially could regulate GMC proliferation and because the extracellular 3',5'-cAMP-adenosine pathway (i.e., the conversion of extracellular 3',5'-cAMP to 5'-AMP and adenosine on the cell surface) could generate adenosine in the biophase of GMC receptors, we investigated the role of the 3',5'-cAMP-adenosine pathway in modulating growth [cell proliferation, DNA synthesis ([(3)H]thymidine incorporation), collagen synthesis ([(3)H]proline incorporation), and mitogen-activated protein kinase activity] of GMCs. The addition of exogenous 3',5'-cAMP to human GMCs increased extracellular levels of 5'-AMP, adenosine, and inosine, and 3-isobutyl-1-methylxanthine (phosphodiesterase inhibitor), 1,3-dipropyl-8-p-sulfophenylxanthine (ecto-phosphodiesterase inhibitor), and alpha,beta-methylene-adenosine-5'-diphosphate (ecto-5'-nucleotidase inhibitor) attenuated the increases in adenosine and inosine. Forskolin augmented extracellular 3',5'-cAMP and adenosine concentrations, and 2',5'-dideoxyadenosine (adenylyl cyclase inhibitor) blocked these increases. Exogenous 3',5'-cAMP and forskolin inhibited all indices of cell growth, and antagonism of A(2) [(E)-8-(3,4-dimethoxystyryl)-1,3-dipropyl-7-methylxanthine, KF17837] or A(1)/A(2) (1,3-dipropyl-8-p-sulfophenylxanthine, DPSPX), but not A(1) (8-cyclopentyl-1,3-dipropylxanthine), or A(3){N-(2-methoxyphenyl)-N'-[2-(3-pyridinyl)-4-quinazolinyl]-urea, VUF5574}, adenosine receptors blocked the growth-inhibitory actions of exogenous 3',5'-cAMP, but not the effects of 8-bromo-3',5'-cAMP (stable 3',5'-cAMP analog). Erythro-9-(2-hydroxy-3-nonyl)adenine (adenosine deaminase inhibitor) plus 5-iodotubercidin (adenosine kinase inhibitor) enhanced the growth inhibition by exogenous 3',5'-cAMP and forskolin, and A(2) receptor antagonism blocked this effect. In rat GMCs, down-regulation of A(2B) receptors with antisense, but not sense or scrambled, oligonucleotides abrogated the inhibitory effects of 3',5'-cAMP and forskolin on cell growth. The extracellular 3',5'-cAMP-adenosine pathway exists in GMCs and attenuates cell growth via A(2B) receptors. Pharmacological augmentation of this pathway could abate pathological glomerular remodeling.
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Affiliation(s)
- Raghvendra K Dubey
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15219-3130, USA
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31
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Choi M, Yoon J, Choi C. Label-free optical control of arterial contraction. JOURNAL OF BIOMEDICAL OPTICS 2010; 15:015006. [PMID: 20210446 DOI: 10.1117/1.3316404] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The diameters of blood vessels, especially in the brain, change dynamically over time to provide sufficient blood supply as needed. No existing technique allows noninvasive control of vascular diameter in vivo. We report that label-free irradiation with a femtosecond pulsed laser can trigger blood vessel contraction in vivo. In response to laser irradiation, cultured vascular smooth muscle cells showed a rapid increase in calcium concentration, followed by cell contraction. In a murine thinned skull window model, laser irradiation focused in the arterial vessel wall caused localized vascular contraction, followed by recovery. The nonlinear nature of the pulsed laser allowed highly specific targeting of subcortical vessels without affecting the surrounding region. We believe that femtosecond pulsed laser irradiation will become a useful experimental tool in the field of vascular biology.
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Affiliation(s)
- Myunghwan Choi
- Korea Advanced Institute of Science and Technology (KAIST), Department of Bio and Brain Engineering, Yuseong-gu, Daejeon, Korea
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St Hilaire C, Carroll SH, Chen H, Ravid K. Mechanisms of induction of adenosine receptor genes and its functional significance. J Cell Physiol 2008; 218:35-44. [PMID: 18767039 DOI: 10.1002/jcp.21579] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Adenosine is a metabolite generated and released from cells, particularly under injury or stress. It elicits protective or damaging responses via signaling through the adenosine receptors, including the adenylyl cyclase inhibitory A(1) and A(3), and the adenylyl cyclase stimulatory A(2A) and A(2B). Multiple adenosine receptor types, including stimulatory and inhibitory, can be found in the same cell, suggesting that a careful balance of adenosine receptor expression in a particular cell is necessary for a specific adenosine-induced response. This balance could be controlled by differential expression of the adenosine receptor genes under different stimuli. Here, we have reviewed an array of studies that have characterized basal or induced expression of the adenosine receptors and common as well as distinct mechanisms of effect, in hopes that ongoing studies on this topic will further elucidate detailed mechanisms of adenosine receptor regulation, leading to potential therapeutic applications.
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Affiliation(s)
- Cynthia St Hilaire
- Department of Biochemistry and Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, Massachusetts 02118, USA
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St Hilaire C, Koupenova M, Carroll SH, Smith BD, Ravid K. TNF-alpha upregulates the A2B adenosine receptor gene: The role of NAD(P)H oxidase 4. Biochem Biophys Res Commun 2008; 375:292-6. [PMID: 18647598 DOI: 10.1016/j.bbrc.2008.07.059] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2008] [Accepted: 07/15/2008] [Indexed: 12/11/2022]
Abstract
Proliferation of vascular smooth muscle cells (VSMC), oxidative stress, and elevated inflammatory cytokines are some of the components that contribute to plaque formation in the vasculature. The cytokine tumor necrosis factor-alpha (TNF-alpha) is released during vascular injury, and contributes to lesion formation also by affecting VSMC proliferation. Recently, an A(2B) adenosine receptor (A(2B)AR) knockout mouse illustrated that this receptor is a tissue protector, in that it inhibits VSMC proliferation and attenuates the inflammatory response following injury, including the release of TNF-alpha. Here, we show a regulatory loop by which TNF-alpha upregulates the A(2B)AR in VSMC in vitro and in vivo. The effect of this cytokine is mimicked by its known downstream target, NAD(P)H oxidase 4 (Nox4). Nox4 upregulates the A(2B)AR, and Nox inhibitors dampen the effect of TNF-alpha. Hence, our study is the first to show that signaling associated with Nox4 is also able to upregulate the tissue protecting A(2B)AR.
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Affiliation(s)
- Cynthia St Hilaire
- Department of Biochemistry, The Whitaker Cardiovascular Institute, Boston University School of Medicine, 715 Albany Street, Boston, MA 02118, USA
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Martinelli A, Tuccinardi T. Molecular modeling of adenosine receptors: new results and trends. Med Res Rev 2008; 28:247-77. [PMID: 17492754 DOI: 10.1002/med.20106] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Adenosine is a ubiquitous neuromodulator, which carries out its biological task by stimulating four cell surface receptors (A(1), A(2A), A(2B), and A(3)). Adenosine receptors (ARs) are members of the superfamily of G protein-coupled receptors (GPCRs). Their discovery opened up new avenues for potential drug treatment of a variety of conditions such as asthma, neurodegenerative disorders, chronic inflammatory diseases, and many other physiopathological states that are believed to be associated with changes in adenosine levels. Knowledge of the 3D structure of ARs could be of great help in the task of understanding their function and in the rational design of specific ligands. However, since GPCRs are membrane-bound proteins, high-resolution structural characterization is still an extremely difficult task. For this reason, great importance has been placed on molecular modeling studies and, particularly in the last few years, on homology modeling (HM) techniques. The publication of the first high-resolution crystal structure for bovine rhodopsin (bRh), a GPCR superfamily member, provides the option of utilizing HM to generate 3D models based on detailed structural information. In this review we report, analyze, and compare the main experimental data, computational HM procedures and validation methods used for ARs, describing in detail the most successful results.
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Affiliation(s)
- Adriano Martinelli
- Dipartimento di Scienze Farmaceutiche, Università di Pisa, via Bonanno 6, 56126 Pisa, Italy.
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35
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Tabrizi MA, Baraldi PG, Preti D, Romagnoli R, Saponaro G, Baraldi S, Moorman AR, Zaid AN, Varani K, Borea PA. 1,3-Dipropyl-8-(1-phenylacetamide-1H-pyrazol-3-yl)-xanthine derivatives as highly potent and selective human A2B adenosine receptor antagonists. Bioorg Med Chem 2008; 16:2419-30. [DOI: 10.1016/j.bmc.2007.11.058] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2007] [Revised: 11/14/2007] [Accepted: 11/21/2007] [Indexed: 10/22/2022]
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Lambertucci C, Cristalli G, Dal Ben D, Kachare DD, Bolcato C, Klotz KN, Spalluto G, Volpini R. New 2,6,9-trisubstituted adenines as adenosine receptor antagonists: a preliminary SAR profile. Purinergic Signal 2007; 3:339-46. [PMID: 18404447 PMCID: PMC2072915 DOI: 10.1007/s11302-007-9068-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2007] [Accepted: 07/31/2007] [Indexed: 11/30/2022] Open
Abstract
A new series of 2,6,9-trisubstituted adenines (5-14) have been prepared and evaluated in radioligand binding studies for their affinity at the human A(1), A(2A) and A(3) adenosine receptors and in adenylyl cyclase experiments for their potency at the human A(2B) subtype. From this preliminary study the conclusion can be drawn that introduction of bulky chains at the N (6) position of 9-propyladenine significantly increased binding affinity at the human A(1) and A(3) adenosine receptors, while the presence of a chlorine atom at the 2 position resulted in a not univocal effect, depending on the receptor subtype and/or on the substituent present in the N (6) position. However, in all cases, the presence in the 2 position of a chlorine atom favoured the interaction with the A(2A) subtype. These results demonstrated that, although the synthesized compounds were found to be quite inactive at the human A(2B) subtype, adenine is a useful template for further development of simplified adenosine receptor antagonists with distinct receptor selectivity profiles.
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Affiliation(s)
- Catia Lambertucci
- Department of Chemical Sciences, University of Camerino, 62032 Camerino, Italy
| | - Gloria Cristalli
- Department of Chemical Sciences, University of Camerino, 62032 Camerino, Italy
| | - Diego Dal Ben
- Department of Chemical Sciences, University of Camerino, 62032 Camerino, Italy
| | - Dhuldeo D. Kachare
- Department of Chemical Sciences, University of Camerino, 62032 Camerino, Italy
| | - Chiara Bolcato
- Department of Pharmaceutical Sciences, University of Trieste, 34127 Trieste, Italy
| | - Karl-Norbert Klotz
- Institut für Pharmakologie und Toxikologie, Universität Würzburg, 97078 Würzburg, Germany
| | - Giampiero Spalluto
- Department of Pharmaceutical Sciences, University of Trieste, 34127 Trieste, Italy
- Dipartimento di Scienze Farmaceutiche, p.le Europa, 1, 34127 Trieste, Italy
| | - Rosaria Volpini
- Department of Chemical Sciences, University of Camerino, 62032 Camerino, Italy
- Dipartimento di Scienze Chimiche, via S. Agostino, 1, 62032 Camerino, Italy
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Kalkan S, Hocaoglu N, Akgun A, Gidener S, Tuncok Y. Effects of adenosine receptor antagonists on amitriptyline-induced vasodilation in rat isolated aorta. Clin Toxicol (Phila) 2007; 45:600-4. [PMID: 17558638 DOI: 10.1080/15563650701397068] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
BACKGROUND Although we have previously demonstrated the beneficial effects of adenosine receptor antagonists in preventing cardiovascular toxicity of amitriptyline in rats, it is not clear whether adenosine receptors in heart or in vasculature are dominant. The aim of the current study was to investigate the role of adenosine A(2a) receptors on amitriptyline-induced vasodilation in rat isolated aorta. METHODS After determining EC(80) of noradrenalin (NA) (the concentration of noradrenalin that produces 80% of maximal contractile response) as 10(-5)M, the IC(50) value of amitriptyline was measured in rat isolated aorta (the drug concentration causing a half- maximal inhibition of contractile responses to NA); IC(50) of amitriptyline was then compared in the presence of the DPCPX (a selective adenosine A(1) antagonist), CSC (a selective A(2a) antagonist) or DMSO (a solvent for adenosine antagonists). Statistical analysis was done using the Student t test. RESULTS Amitriptyline-inhibited 49.9 +/- 3.7 % contractile response to NA on aorta segments at 1.8 x 10(-5)M (IC(50)). While DPCPX increased amitriptyline-induced inhibition on contractile response to NA dose dependently, CSC decreased the contractile response to NA only at 10(-5)M. DMSO did not change amitriptyline-induced IC(50). CONCLUSION Adenosine A(2a) receptor stimulation seems to be responsible partly for amitriptyline-induced vasodilation and hypotension since the adenosine A(1) antagonist, DPCPX, increased amitriptyline-induced vasodilation in rat isolated aorta.
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Affiliation(s)
- Sule Kalkan
- Dokuz Eylul University, School of Medicine, Department of Pharmacology, Izmir, Turkey.
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Yang D, Zhang Y, Nguyen HG, Koupenova M, Chauhan AK, Makitalo M, Jones MR, Hilaire CS, Seldin DC, Toselli P, Lamperti E, Schreiber BM, Gavras H, Wagner DD, Ravid K. The A2B adenosine receptor protects against inflammation and excessive vascular adhesion. J Clin Invest 2006; 116:1913-23. [PMID: 16823489 PMCID: PMC1483170 DOI: 10.1172/jci27933] [Citation(s) in RCA: 282] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2006] [Accepted: 04/25/2006] [Indexed: 01/22/2023] Open
Abstract
Adenosine has been described as playing a role in the control of inflammation, but it has not been certain which of its receptors mediate this effect. Here, we generated an A2B adenosine receptor-knockout/reporter gene-knock-in (A2BAR-knockout/reporter gene-knock-in) mouse model and showed receptor gene expression in the vasculature and macrophages, the ablation of which causes low-grade inflammation compared with age-, sex-, and strain-matched control mice. Augmentation of proinflammatory cytokines, such as TNF-alpha, and a consequent downregulation of IkappaB-alpha are the underlying mechanisms for an observed upregulation of adhesion molecules in the vasculature of these A2BAR-null mice. Intriguingly, leukocyte adhesion to the vasculature is significantly increased in the A2BAR-knockout mice. Exposure to an endotoxin results in augmented proinflammatory cytokine levels in A2BAR-null mice compared with control mice. Bone marrow transplantations indicated that bone marrow (and to a lesser extent vascular) A2BARs regulate these processes. Hence, we identify the A2BAR as a new critical regulator of inflammation and vascular adhesion primarily via signals from hematopoietic cells to the vasculature, focusing attention on the receptor as a therapeutic target.
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Affiliation(s)
- Dan Yang
- Department of Biochemistry and Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, Massachusetts, USA.
CBR Institute for Biomedical Research and Department of Pathology, Harvard Medical School, Boston, Massachusetts, USA.
Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Ying Zhang
- Department of Biochemistry and Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, Massachusetts, USA.
CBR Institute for Biomedical Research and Department of Pathology, Harvard Medical School, Boston, Massachusetts, USA.
Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Hao G. Nguyen
- Department of Biochemistry and Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, Massachusetts, USA.
CBR Institute for Biomedical Research and Department of Pathology, Harvard Medical School, Boston, Massachusetts, USA.
Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Milka Koupenova
- Department of Biochemistry and Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, Massachusetts, USA.
CBR Institute for Biomedical Research and Department of Pathology, Harvard Medical School, Boston, Massachusetts, USA.
Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Anil K. Chauhan
- Department of Biochemistry and Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, Massachusetts, USA.
CBR Institute for Biomedical Research and Department of Pathology, Harvard Medical School, Boston, Massachusetts, USA.
Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Maria Makitalo
- Department of Biochemistry and Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, Massachusetts, USA.
CBR Institute for Biomedical Research and Department of Pathology, Harvard Medical School, Boston, Massachusetts, USA.
Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Matthew R. Jones
- Department of Biochemistry and Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, Massachusetts, USA.
CBR Institute for Biomedical Research and Department of Pathology, Harvard Medical School, Boston, Massachusetts, USA.
Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Cynthia St. Hilaire
- Department of Biochemistry and Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, Massachusetts, USA.
CBR Institute for Biomedical Research and Department of Pathology, Harvard Medical School, Boston, Massachusetts, USA.
Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - David C. Seldin
- Department of Biochemistry and Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, Massachusetts, USA.
CBR Institute for Biomedical Research and Department of Pathology, Harvard Medical School, Boston, Massachusetts, USA.
Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Paul Toselli
- Department of Biochemistry and Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, Massachusetts, USA.
CBR Institute for Biomedical Research and Department of Pathology, Harvard Medical School, Boston, Massachusetts, USA.
Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Edward Lamperti
- Department of Biochemistry and Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, Massachusetts, USA.
CBR Institute for Biomedical Research and Department of Pathology, Harvard Medical School, Boston, Massachusetts, USA.
Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Barbara M. Schreiber
- Department of Biochemistry and Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, Massachusetts, USA.
CBR Institute for Biomedical Research and Department of Pathology, Harvard Medical School, Boston, Massachusetts, USA.
Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Haralambos Gavras
- Department of Biochemistry and Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, Massachusetts, USA.
CBR Institute for Biomedical Research and Department of Pathology, Harvard Medical School, Boston, Massachusetts, USA.
Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Denisa D. Wagner
- Department of Biochemistry and Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, Massachusetts, USA.
CBR Institute for Biomedical Research and Department of Pathology, Harvard Medical School, Boston, Massachusetts, USA.
Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Katya Ravid
- Department of Biochemistry and Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, Massachusetts, USA.
CBR Institute for Biomedical Research and Department of Pathology, Harvard Medical School, Boston, Massachusetts, USA.
Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
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Varani K, Gessi S, Merighi S, Vincenzi F, Cattabriga E, Benini A, Klotz KN, Baraldi PG, Tabrizi MA, Lennan SM, Leung E, Borea PA. Pharmacological characterization of novel adenosine ligands in recombinant and native human A2B receptors. Biochem Pharmacol 2005; 70:1601-12. [PMID: 16219300 DOI: 10.1016/j.bcp.2005.08.018] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2005] [Revised: 08/31/2005] [Accepted: 08/31/2005] [Indexed: 01/11/2023]
Abstract
The present study was designed to evaluate the effects of novel and recognised compounds at human recombinant A(2B) adenosine receptors expressed in Chinese hamster ovary (hA(2B)CHO), in human embryonic kidney 293 (hA(2B)HEK-293) and at endogenous A(2B) receptors in human mast cells (HMC-1). Saturation binding experiments performed using the new high affinity A(2B) adenosine radioligand [(3)H]-N-benzo[1,3]dioxol-5-yl-2-[5-(2,6-dioxo-1,3-dipropyl-2,3,6,7-tetra hydro-1H-purin-8-yl)-1-methyl-1H-pyrazol-3-yloxy]-acetamide ([(3)H]-MRE 2029F20) revealed a single class of binding sites in hA(2B)CHO, hA(2B)HEK-293 and HMC-1 cells with K(D) (nM) of 1.65+/-0.18, 2.83+/-0.34, 2.62+/-0.27 and B(max) (fmol/mg protein) of 36+/-4, 475+/-50 and 128+/-15, respectively. The pharmacological profile of new compounds, determined in inhibition binding experiments in hA(2B)HEK-293 cells using [(3)H]-MRE 2029F20, showed a rank order of potency typical of the A(2B) receptors with K(i) values in the range 3.2-28nM. In functional assays, recognised agonists and antagonists were studied by evaluating their capability to modulate the cAMP production in hA(2B)CHO and in HMC-1 cells. Novel compounds were able to decrease NECA-stimulated cAMP production in hA(2B)CHO and in HMC-1 cells showing a high potency. New compounds were also able to inhibit cAMP levels in the absence of NECA and in the presence of forskolin stimulation in hA(2B)CHO and in HMC-1 cells. In HEK-293 cells MRE 2029F20 reduced cAMP basal levels with an IC(50) value of 2.9+/-0.3nM. These results suggest that novel compounds are antagonists with an inverse agonist activity in recombinant and native human A(2B) receptors.
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Affiliation(s)
- Katia Varani
- Department of Clinical and Experimental Medicine, Pharmacology Unit, University of Ferrara, via Fossato di Mortara 17-19, 44100 Ferrara, Italy
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40
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Jones MR, Zhao Z, Sullivan CP, Schreiber BM, Stone PJ, Toselli PA, Kagan HM, Cohen RA, Ravid K. A(3) adenosine receptor deficiency does not influence atherogenesis. J Cell Biochem 2005; 92:1034-43. [PMID: 15258925 DOI: 10.1002/jcb.20122] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Atherosclerosis is a multifactorial disease, the progression of which is modulated by several factors, including inflammation and hypercholesterolemia. The A(3) adenosine receptor (A(3)AR) has been reported to affect mast cell degranulation leading to inflammation, as well as to influence cardiovascular homeostasis. Here, we show that its deletion can also impact vascular smooth muscle cell (VSMC) proliferation in vitro. Based on these observations, we hypothesized that A(3)AR deficiency would affect atheromatous lesion development in vivo. Our results indicate that the expression of the matrix enzyme lysyl oxidase (LO) is increased while the proliferation potential of VSMC is decreased in A(3)AR-null aortas. This is in accordance with the previously reported inverse correlation between LO level and proliferation. Nevertheless, we found that A(3)-deficiency does not protect vessels against atherogenesis. This was demonstrated in mouse models of high fat diet-induced atherosclerosis and guidewire-induced femoral artery injury. We conclude that the contributions of the A(3)AR to inflammation and to modulating LO levels are not significant enough to control vascular response to injury.
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MESH Headings
- Animals
- Aorta/cytology
- Aorta/enzymology
- Aorta/metabolism
- Arteriosclerosis/genetics
- Base Sequence
- Blotting, Western
- Cells, Cultured
- DNA Primers
- DNA Replication
- Elastin/metabolism
- Immunohistochemistry
- Mice
- Mice, Inbred C57BL
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/enzymology
- Muscle, Smooth, Vascular/metabolism
- Protein-Lysine 6-Oxidase/metabolism
- Receptor, Adenosine A3/genetics
- Receptor, Adenosine A3/physiology
- Up-Regulation
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Affiliation(s)
- Matthew R Jones
- Department of Biochemistry, Boston University School of Medicine, Boston, Massachusetts 02118, USA
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41
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Abstract
Many cell types in the kidney express adenosine receptors, and adenosine has multiple effects on renal function. Although adenosine is produced within the kidney by several biochemical reactions, recent studies support a novel mechanism for renal adenosine production, the extracellular cAMP-adenosine pathway. This extracellular cAMP-adenosine pathway is initiated by efflux of cAMP from cells following activation of adenylyl cyclase. Extracellular cAMP is then converted to adenosine by the serial actions of ecto-phosphodiesterase and ecto-5'-nucleotidase. When extracellular cAMP is converted to adenosine near the biophase of cAMP production and efflux, this local extracellular cAMP-adenosine pathway permits tight coupling of the site of adenosine production to the site of adenosine receptors. cAMP in renal compartments may also be formed by tissues/organs remote from the kidney. For example, stimulation of hepatic adenylyl cyclase by the pancreatic hormone glucagon increases circulating cAMP, which is filtered at the glomerulus and concentrated in the tubular lumen as water is extracted from the ultrafiltrate. Conversion of hepatic-derived cAMP to adenosine in the kidney completes a pancreatohepatorenal cAMP-adenosine pathway that may serve as an endocrine link between the pancreas, liver, and kidney.
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Affiliation(s)
- Edwin K Jackson
- Center for Clinical Pharmacology, Department of Pharmacology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261, USA. edj+@pitt.edu
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42
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Cheng MK, Doumad AB, Jiang H, Falck JR, McGiff JC, Carroll MA. Epoxyeicosatrienoic acids mediate adenosine-induced vasodilation in rat preglomerular microvessels (PGMV) via A2A receptors. Br J Pharmacol 2004; 141:441-8. [PMID: 14718251 PMCID: PMC1574221 DOI: 10.1038/sj.bjp.0705640] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Activation of rat adenosine2A receptors (A2A R) dilates preglomerular microvessels (PGMV), an effect mediated by epoxyeicosatrienoic acids (EETs). Incubation of PGMV with a selective A2A R agonist, 2-p-(2-carboxyethyl) phenethylamino-5'-N-ethylcarboxamidoadenosine (CGS 21680; 100 microM), increased isolated PGMV EET levels to 7.57+/-1.53 ng mg-1 protein from 1.06+/-0.22 ng mg-1 protein in controls (P<0.05), without affecting hydroxyeicosatetraenoic acid (HETE) levels (10.8+/-0.69 vs 11.02+/-0.74 ng mg-1 protein). CGS 21680-stimulated EETs was abolished by preincubation with an A2A R antagonist, 4-(2-[7-amino-2-(2-furyl)[1,2,4]triazolo[2,3-a][1,3,5]triazin-5-ylamino]ethyl)phenol (ZM241385) (100 microM). A selective epoxygenase inhibitor, methylsulfonyl-propargyloxyphenylhexanamide (MS-PPOH; 12 microM) prevented CGS 21680-induced increase in EETs, indicating inhibition of de novo synthesis of EETs. In pressurized (80 mmHg) renal arcuate arteries (110-130 microm) preconstricted with phenylephrine (20 nM), superfusion with CGS 21680 (0.01-10 microM) increased the internal diameter (i.d.) concentration-dependently; vasodilation was independent of nitric oxide and cyclooxygenase activity. CGS 21680 (10 microM) increased i.d. by 32+/-6 microm; vasodilation was prevented by inhibition of EET synthesis with MS-PPOH. Addition of 3 nM 5,6-EET, 8,9-EET and 11,12-EET increased i.d. by 53+/-9, 17+/-4 and 53+/-5 microm, respectively, whereas 14,15-EET was inactive. The responses to 5,6-EET were, however, significantly inhibited by indomethacin. We conclude that 11,12-EET is the likely mediator of A2A R-induced dilation of rat PGMV. Activation of A2A R coupled to de novo EET stimulation may represent an important mechanism in regulating preglomerular microvascular tone. British Journal of Pharmacology (2004) 141, 441-448. doi:10.1038/sj.bjp.0705640
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Affiliation(s)
- M K Cheng
- Department of Pharmacology, New York Medical College, Valhalla, NY 10595, U.S.A
| | - A B Doumad
- Department of Pharmacology, New York Medical College, Valhalla, NY 10595, U.S.A
| | - H Jiang
- Department of Pharmacology, New York Medical College, Valhalla, NY 10595, U.S.A
| | - J R Falck
- Department of Molecular Genetics, University of Texas, Southwestern Medical Center, Dallas, TX 75235, U.S.A
| | - J C McGiff
- Department of Pharmacology, New York Medical College, Valhalla, NY 10595, U.S.A
| | - M A Carroll
- Department of Pharmacology, New York Medical College, Valhalla, NY 10595, U.S.A
- Author for correspondence:
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43
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Yaar R, Jones MR, Chen JF, Ravid K. Animal models for the study of adenosine receptor function. J Cell Physiol 2004; 202:9-20. [PMID: 15389588 DOI: 10.1002/jcp.20138] [Citation(s) in RCA: 109] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Adenosine receptors represent a family of G-protein coupled receptors that are ubiquitously expressed in a wide variety of tissues. This family contains four receptor subtypes: A1 and A3, which mediate inhibition of adenylyl cyclase; and A2a and A2b, which mediate stimulation of this enzyme. Currently, all receptor subtypes have been genetically deleted in mouse models except for the A2b adenosine receptor, and some have been overexpressed in selective tissues of transgenic mice. Studies involving these transgenic mice indicated that receptor levels are rate limiting, as effects were amplified upon increases in receptor level. The knockout models pointed to clusters of activities related to the physiologies of the cardiovascular and the nervous systems, which are either reduced or enhanced upon specific receptor deletion. Interestingly, the trend of effects on these systems is similar in the A1 and A3 adenosine receptor knockout mice and opposite to the effects observed in the A2a adenosine receptor knockout model. This review summarizes in vitro studies on pathways affected by each adenosine receptor, and primarily focuses on the above in vivo models generated to investigate the physiologic role of adenosine receptors. Furthermore, it illustrates the need for multiple adenosine receptor subtype deficiency studies in mice and the deletion of the A2b subtype.
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Affiliation(s)
- R Yaar
- Department of Biochemistry, Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, Massachusetts, USA
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44
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Mujoomdar M, Hoskin D, Blay J. Adenosine stimulation of the proliferation of colorectal carcinoma cell lines. Roles of cell density and adenosine metabolism. Biochem Pharmacol 2003; 66:1737-47. [PMID: 14563484 DOI: 10.1016/s0006-2952(03)00548-3] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Adenosine is a purine nucleoside which is present at micromolar concentrations in the extracellular fluid of solid cancers as a result of tissue hypoxia. Adenosine acts to promote tumor survival by inhibiting the cell-mediated anti-tumor immune response. However, its role in modulating proliferation of the tumor cell population is unclear. Differing results have been obtained using adenosine analogues or by interfering with adenosine metabolism. We examined the effect of adenosine itself on DNA synthesis and cell growth in six different human and mouse colorectal carcinoma cell lines, from different sites and at different stages of differentiation. Adenosine given as a single dose consistently stimulated DNA synthesis and cell proliferation in all cell lines tested, with an EC(50) of 3.8-30 microM and a maximum stimulation being reached at 10-100 microM. AMP and ATP also stimulated cell proliferation at similar doses. The stimulation by adenosine varied depending upon the culture cell density, with the greatest mitogenic effect at subconfluent densities. Adenosine was metabolized by cellular adenosine deaminase and adenosine kinase. The half-life (t(1/2)) for the decline in adenosine concentration in the medium following a single addition was between 40 min and 3 hr depending on the cell line and culture conditions. The rate of production of endogenous adenosine was low under normoxic culture conditions. Continuous dosing of cultures with adenosine to provide a steady-state concentration showed that proliferation could be stimulated by low micromolar concentrations of adenosine. We conclude that adenosine is stimulatory to the growth of human colorectal carcinoma cells at concentrations present within the tumor extracellular environment.
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Affiliation(s)
- Michelle Mujoomdar
- Department of Pharmacology, Faculty of Medicine, Sir Charles Tupper Medical Building, Dalhousie University, Halifax, NS, Canada B3H 4H7
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45
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Abstract
The purine nucleoside adenosine acts via four distinct adenosine receptor subtypes: the adenosine A(1), A(2A), A(2B), and A(3) receptor. They are all G protein-coupled receptors (GPCR) coupling to classical second messenger pathways such as modulation of cAMP production or the phospholipase C (PLC) pathway. In addition, they couple to mitogen-activated protein kinases (MAPK), which could give them a role in cell growth, survival, death and differentiation. Although each of the adenosine receptors can activate one or more of the MAPKs, the mechanisms appear to differ substantially, both between receptor subtypes in the same cell type and between the same receptor in different cell types.
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Affiliation(s)
- Gunnar Schulte
- Department of Physiology and Pharmacology, Karolinska Institutet, S-171 77, Stockholm, Sweden.
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46
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Nucciarelli F, Mearini E, Minelli A. Effects of adenosine on prostate adenocarcinoma PC-3 and bladder carcinoma J82 cell lines. Drug Dev Res 2003. [DOI: 10.1002/ddr.10183] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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47
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Jackson EK, Dubey RK. Role of the extracellular cAMP-adenosine pathway in renal physiology. Am J Physiol Renal Physiol 2001; 281:F597-612. [PMID: 11553506 DOI: 10.1152/ajprenal.2001.281.4.f597] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Adenosine exerts physiologically significant receptor-mediated effects on renal function. For example, adenosine participates in the regulation of preglomerular and postglomerular vascular resistances, glomerular filtration rate, renin release, epithelial transport, intrarenal inflammation, and growth of mesangial and vascular smooth muscle cells. It is important, therefore, to understand the mechanisms that generate extracellular adenosine within the kidney. In addition to three "classic" pathways of adenosine biosynthesis, contemporary studies are revealing a novel mechanism for renal adenosine production termed the "extracellular cAMP-adenosine pathway." The extracellular cAMP-adenosine pathway is defined as the egress of cAMP from cells during activation of adenylyl cyclase, followed by the extracellular conversion of cAMP to adenosine by the serial actions of ecto-phosphodiesterase and ecto-5'-nucleotidase. This mechanism of extracellular adenosine production may provide hormonal control of adenosine levels in the cell-surface biophase in which adenosine receptors reside. Tight coupling of the site of adenosine production to the site of adenosine receptors would permit a low-capacity mechanism of adenosine biosynthesis to have a large impact on adenosine receptor activation. The purposes of this review are to summarize the physiological roles of adenosine in the kidney; to describe the classic pathways of renal adenosine biosynthesis; to review the evidence for the existence of the extracellular cAMP-adenosine pathway; and to describe possible physiological roles of the extracellular cAMP-adenosine pathway, with particular emphasis on the kidney.
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Affiliation(s)
- E K Jackson
- Department of Pharmacology, University of Pittsburgh School of Medicine, 3550 Terrace St., Pittsburgh, PA 15261, USA. edj+@pitt.edu
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48
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Akalal DB, Nagle GT. Mollusk-derived growth factor: cloning and developmental expression in the central nervous system and reproductive tract of Aplysia. BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 2001; 91:163-8. [PMID: 11457505 DOI: 10.1016/s0169-328x(01)00127-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We have isolated and characterized an atrial gland cDNA that corrects the previously reported sequence for Aplysia atrial gland granule-specific antigen (AGSA), a glycoprotein of unknown function. We designated the protein mollusk-derived growth factor (MDGF) to distinguish the revised sequence from AGSA and to emphasize its similarity to an insect-derived growth factor (IDGF). We describe MDGF mRNA expression that suggests a possible role during embryonic development and CNS injury repair.
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Affiliation(s)
- D B Akalal
- Marine Biomedical Institute and Department of Anatomy and Neurosciences, University of Texas Medical Branch, Medical Research Building, Galveston, TX 77555-1043, USA.
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49
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Baraldi PG, Cacciari B, Romagnoli R, Klotz KN, Spalluto G, Varani K, Gessi S, Merighi S, Borea PA. Pyrazolo[4,3-e]1,2,4-triazolo[1,5-c]pyrimidine derivatives as adenosine receptor ligands: A starting point for searching A2B adenosine receptor antagonists. Drug Dev Res 2001. [DOI: 10.1002/ddr.1191] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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50
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Sommerschild HT, Kirkebøen KA. Adenosine and cardioprotection during ischaemia and reperfusion--an overview. Acta Anaesthesiol Scand 2000; 44:1038-55. [PMID: 11028722 DOI: 10.1034/j.1399-6576.2000.440903.x] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Adenosine is a local hormone, with numerous tissue-specific biological functions. In the myocardium, adenosine is released in small amounts at constant basal rate during normoxia. During ischaemia the production of adenosine increases several fold due to breakdown of adenosine triphosphate (ATP). Increased production of adenosine causes coronary vasodilatation. Thus, adenosine couples myocardial metabolism and flow during ischaemia and is called a homeostatic or "retaliatory metabolite". Furthermore, adenosine has electrophysiological effects in supraventricular tissue, causing a decrease in heart rate. In 1985 it was discovered that adenosine also exerts cardioprotective effects directly on cardiomyocytes. The aim of this review is to give an overview of the role of adenosine as a directly cytoprotective agent during myocardial ischaemia and reperfusion. We will focus on its effects on the myocytes, elicited by stimulation of adenosine receptors in sarcolemma, which triggers intracellular signalling systems. We will also address the new aspect that adenosine can influence regulation of gene expression. There is evidence that the myocardium is capable of endogenous adaptation in response to ischaemia, namely "hibernation" and early and late phases of "preconditioning". Endogenous substances produced during ischaemia probably trigger these responses. We will discuss the role of adenosine in these different settings. Adenosine can be given exogenously through intravasal routes; however, this review will also focus on the effects of endogenously produced adenosine. We will discuss pharmacological ways to increase endogenous levels of adenosine, and the effects of such interventions during ischaemia and reperfusion. Finally, we will review results from studies in humans together with relevant experimental studies, and indicate potential therapeutic implications of adenosine.
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Affiliation(s)
- H T Sommerschild
- lnstitute for Experimental Medical Research, Ullevål Hospital, Oslo, Norway.
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