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Ovari I, Viczjan G, Erdei T, Takacs B, Tarjanyi V, Zsuga J, Szucs M, Szilvassy Z, Juhasz B, Gesztelyi R. The influence of the way of regression on the results obtained by the receptorial responsiveness method (RRM), a procedure to estimate a change in the concentration of a pharmacological agonist near the receptor. Front Pharmacol 2024; 15:1375955. [PMID: 38756379 PMCID: PMC11096549 DOI: 10.3389/fphar.2024.1375955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Accepted: 04/11/2024] [Indexed: 05/18/2024] Open
Abstract
The receptorial responsiveness method (RRM) enables the estimation of a change in concentration of an (even degradable) agonist, near its receptor, via curve fitting to (at least) two concentration-effect (E/c) curves of a stable agonist. One curve should be generated before this change, and the other afterwards, in the same system. It follows that RRM yields a surrogate parameter ("cx") as the concentration of the stable agonist being equieffective with the change in concentration of the other agonist. However, regression can be conducted several ways, which can affect the accuracy, precision and ease-of-use. This study utilized data of previous ex vivo investigations. Known concentrations of stable agonists were estimated with RRM by performing individual (local) or global fitting, this latter with one or two model(s), using a logarithmic (logcx) or a nonlogarithmic (cx) parameter (the latter in a complex or in a simplified equation), with ordinary least-squares or robust regression, and with an "all-at-once" or "pairwise" fitting manner. We found that the simplified model containing logcx was superior to all alternative models. The most complicated individual regression was the most accurate, followed closely by the moderately complicated two-model global regression and then by the easy-to-perform one-model global regression. The two-model global fitting was the most precise, followed by the individual fitting (closely) and by the one-model global fitting (from afar). Pairwise fitting (two E/c curves at once) improved the estimation. Thus, the two-model global fitting, performed pairwise, and the individual fitting are recommended for RRM, using the simplified model containing logcx.
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Affiliation(s)
- Ignac Ovari
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
- University of Debrecen, Doctoral School of Nutrition and Food Sciences, Debrecen, Hungary
| | - Gabor Viczjan
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Tamas Erdei
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Barbara Takacs
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Vera Tarjanyi
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Judit Zsuga
- Department of Psychiatry, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Miklos Szucs
- Department of Urology and Andrology, Kenezy Gyula Campus, University of Debrecen, Debrecen, Hungary
| | - Zoltan Szilvassy
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Bela Juhasz
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Rudolf Gesztelyi
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
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Viczjan G, Szilagyi A, Takacs B, Ovari I, Szekeres R, Tarjanyi V, Erdei T, Teleki V, Zsuga J, Szilvassy Z, Juhasz B, Varga B, Gesztelyi R. The effect of a long-term treatment with cannabidiol-rich hemp extract oil on the adenosinergic system of the zucker diabetic fatty (ZDF) rat atrium. Front Pharmacol 2022; 13:1043275. [PMID: 36588715 PMCID: PMC9797669 DOI: 10.3389/fphar.2022.1043275] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 12/02/2022] [Indexed: 12/23/2022] Open
Abstract
Cannabidiol (CBD), the most extensively studied non-intoxicating phytocannabinoid, has been attracting a lot of interest worldwide owing to its numerous beneficial effects. The aim of this study was to explore the effect that CBD exerts on the adenosinergic system of paced left atria isolated from obese type Zucker Diabetic Fatty (ZDF) rats, maintained on diabetogenic rat chow, received 60 mg/kg/day CBD or vehicle via gavage for 4 weeks. We found that N6-cyclopentyladenosine (CPA), a relatively stable and poorly transported A1 adenosine receptor agonist, elicited a significantly weaker response in the CBD-treated group than in the vehicle-treated one. In contrast, adenosine, a quickly metabolized and transported adenosine receptor agonist, evoked a significantly stronger response in the CBD-treated group than in the vehicle-treated counterpart (excepting its highest concentrations). These results can be explained only with the adenosine transport inhibitory property of CBD (and not with its adenosine receptor agonist activity). If all the effects of CBD are attributed to the interstitial adenosine accumulation caused by CBD in the myocardium, then a significantly increased adenosinergic activation can be assumed during the long-term oral CBD treatment, suggesting a considerably enhanced adenosinergic protection in the heart. Considering that our results may have been influenced by A1 adenosine receptor downregulation due to the chronic interstitial adenosine accumulation, an adenosinergic activation smaller than it seemed cannot be excluded, but it was above the CBD-naïve level in every case. Additionally, this is the first study offering functional evidence about the adenosine transport inhibitory action of CBD in the myocardium.
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Affiliation(s)
- Gabor Viczjan
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Debrecen, Debrecen, Hungary,University of Debrecen, Doctoral School of Nutrition and Food Sciences, Debrecen, Hungary
| | - Anna Szilagyi
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Barbara Takacs
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Ignac Ovari
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Reka Szekeres
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Vera Tarjanyi
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Tamas Erdei
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Vanda Teleki
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Judit Zsuga
- Department of Psychiatry, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Zoltan Szilvassy
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Bela Juhasz
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Balazs Varga
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Rudolf Gesztelyi
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Debrecen, Debrecen, Hungary,*Correspondence: Rudolf Gesztelyi,
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Martín MG, Dotti CG. Plasma membrane and brain dysfunction of the old: Do we age from our membranes? Front Cell Dev Biol 2022; 10:1031007. [PMID: 36274849 PMCID: PMC9582647 DOI: 10.3389/fcell.2022.1031007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Accepted: 09/20/2022] [Indexed: 11/26/2022] Open
Abstract
One of the characteristics of aging is a gradual hypo-responsiveness of cells to extrinsic stimuli, mainly evident in the pathways that are under hormone control, both in the brain and in peripheral tissues. Age-related resistance, i.e., reduced response of receptors to their ligands, has been shown to Insulin and also to leptin, thyroid hormones and glucocorticoids. In addition, lower activity has been reported in aging for ß-adrenergic receptors, adenosine A2B receptor, and several other G-protein-coupled receptors. One of the mechanisms proposed to explain the loss of sensitivity to hormones and neurotransmitters with age is the loss of receptors, which has been observed in several tissues. Another mechanism that is finding more and more experimental support is related to the changes that occur with age in the lipid composition of the neuronal plasma membrane, which are responsible for changes in the receptors’ coupling efficiency to ligands, signal attenuation and pathway desensitization. In fact, recent works have shown that altered membrane composition—as occurs during neuronal aging—underlies reduced response to glutamate, to the neurotrophin BDNF, and to insulin, all these leading to cognition decay and epigenetic alterations in the old. In this review we present evidence that altered functions of membrane receptors due to altered plasma membrane properties may be a triggering factor in physiological decline, decreased brain function, and increased vulnerability to neuropathology in aging.
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Affiliation(s)
- Mauricio G. Martín
- Cellular and Molecular Neurobiology Department, Instituto Ferreyra (INIMEC)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional de Córdoba (UNC), Córdoba, Argentina
- *Correspondence: Mauricio G. Martín, ; Carlos G. Dotti,
| | - Carlos G. Dotti
- Molecular Neuropathology Unit, Physiological and Pathological Processes Program, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas (CSIC), Universidad Autónoma de Madrid (UAM), Madrid, Spain
- *Correspondence: Mauricio G. Martín, ; Carlos G. Dotti,
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Wölkart G, Stessel H, Fassett E, Teschl E, Friedl K, Trummer M, Schrammel A, Kollau A, Mayer B, Fassett J. Adenosine kinase (ADK) inhibition with ABT-702 induces ADK protein degradation and a distinct form of sustained cardioprotection. Eur J Pharmacol 2022; 927:175050. [PMID: 35618039 DOI: 10.1016/j.ejphar.2022.175050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 05/17/2022] [Accepted: 05/19/2022] [Indexed: 11/18/2022]
Abstract
Pharmacological inhibition of adenosine kinase (ADK), the major route of myocardial adenosine metabolism, can elicit acute cardioprotection against ischemia-reperfusion (IR) by increasing adenosine signaling. Here, we identified a novel, extended effect of the ADK inhibitor, ABT-702, on cardiac ADK protein longevity and investigated its impact on sustained adenosinergic cardioprotection. We found that ABT-702 treatment significantly reduced cardiac ADK protein content in mice 24-72 h after administration (IP or oral). ABT-702 did not alter ADK mRNA levels, but strongly diminished (ADK-L) isoform protein content through a proteasome-dependent mechanism. Langendorff perfusion experiments revealed that hearts from ABT-702-treated mice maintain higher adenosine release long after ABT-702 tissue elimination, accompanied by increased basal coronary flow (CF) and robust tolerance to IR. Sustained cardioprotection by ABT-702 did not involve increased nitric oxide synthase expression, but was completely dependent upon increased adenosine release in the delayed phase (24 h), as indicated by the loss of cardioprotection and CF increase upon perfusion of adenosine deaminase or adenosine receptor antagonist, 8-phenyltheophylline. Importantly, blocking adenosine receptor activity with theophylline during ABT-702 administration prevented ADK degradation, preserved late cardiac ADK activity, diminished CF increase and abolished delayed cardioprotection, indicating that early adenosine receptor signaling induces late ADK degradation to elicit sustained adenosine release. Together, these results indicate that ABT-702 induces a distinct form of delayed cardioprotection mediated by adenosine receptor-dependent, proteasomal degradation of cardiac ADK and enhanced adenosine signaling in the late phase. These findings suggest ADK protein stability may be pharmacologically targeted to achieve sustained adenosinergic cardioprotection.
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Affiliation(s)
- Gerald Wölkart
- Department of Pharmacology and Toxicology, University of Graz, 8010, Graz, Austria
| | - Heike Stessel
- Department of Pharmacology and Toxicology, University of Graz, 8010, Graz, Austria
| | - Erin Fassett
- Department of Pharmacology and Toxicology, University of Graz, 8010, Graz, Austria
| | - Eva Teschl
- Department of Pharmacology and Toxicology, University of Graz, 8010, Graz, Austria
| | - Katrin Friedl
- Department of Pharmacology and Toxicology, University of Graz, 8010, Graz, Austria
| | - Modesta Trummer
- Department of Pharmacology and Toxicology, University of Graz, 8010, Graz, Austria
| | - Astrid Schrammel
- Department of Pharmacology and Toxicology, University of Graz, 8010, Graz, Austria
| | - Alexander Kollau
- Department of Pharmacology and Toxicology, University of Graz, 8010, Graz, Austria
| | - Bernd Mayer
- Department of Pharmacology and Toxicology, University of Graz, 8010, Graz, Austria
| | - John Fassett
- Department of Pharmacology and Toxicology, University of Graz, 8010, Graz, Austria.
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Wragg ES, Pannucci P, Hill SJ, Woolard J, Cooper SL. Involvement of β-adrenoceptors in the cardiovascular responses induced by selective adenosine A 2A and A 2B receptor agonists. Pharmacol Res Perspect 2022; 10:e00975. [PMID: 35643970 PMCID: PMC9148549 DOI: 10.1002/prp2.975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Accepted: 05/09/2022] [Indexed: 11/06/2022] Open
Abstract
A2A and A2B adenosine receptors produce regionally selective regulation of vascular tone and elicit differing effects on mean arterial pressure (MAP), whilst inducing tachycardia. The tachycardia induced by the stimulation of A2A or A2B receptors has been suggested to be mediated by a reflex increase in sympathetic activity. Here, we have investigated the role of β1 - and β2 -adrenoceptors in mediating the different cardiovascular responses to selective A2A and A2B receptor stimulation. Hemodynamic variables were measured in conscious male Sprague-Dawley rats (350-450 g) via pulsed Doppler flowmetry. The effect of intravenous infusion (3 min per dose) of the A2A -selective agonist CGS 21680 (0.1, 0.3, 1.0 µg.kg-1 .min-1 ) or the A2B -selective agonist BAY 60-6583 (4.0, 13.3, 40.0 µg.kg-1 .min-1 ) in the absence or following pre-treatment with the non-selective β-antagonist propranolol (1.0 mg.kg-1 ), the selective β1 -antagonist CGP 20712A (200 µg.kg-1 ), or the selective β2 -antagonist ICI 118,551 (2.0 mg.kg-1 ) was investigated (maintenance doses also administered). CGP 20712A and propranolol significantly reduced the tachycardic response to CGS 21680, with no change in the effect on MAP. ICI 118,551 increased BAY 60-6583-mediated renal and mesenteric flows, but did not affect the heart rate response. CGP 20712A attenuated the BAY 60-6583-induced tachycardia. These data imply a direct stimulation of the sympathetic activity via cardiac β1 -adrenoceptors as a mechanism for the A2A - and A2B -induced tachycardia. However, the regionally selective effects of A2B agonists on vascular conductance were independent of sympathetic activity and may be exploitable for the treatment of acute kidney injury and mesenteric ischemia.
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Affiliation(s)
- Edward S Wragg
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, UK.,Centre of Membrane Proteins and Receptors, University of Birmingham and University of Nottingham, Midlands, UK
| | - Patrizia Pannucci
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, UK.,Centre of Membrane Proteins and Receptors, University of Birmingham and University of Nottingham, Midlands, UK
| | - Stephen J Hill
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, UK.,Centre of Membrane Proteins and Receptors, University of Birmingham and University of Nottingham, Midlands, UK
| | - Jeanette Woolard
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, UK.,Centre of Membrane Proteins and Receptors, University of Birmingham and University of Nottingham, Midlands, UK
| | - Samantha L Cooper
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, UK.,Centre of Membrane Proteins and Receptors, University of Birmingham and University of Nottingham, Midlands, UK
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Skopál A, Kéki T, Tóth PÁ, Csóka B, Koscsó B, Németh ZH, Antonioli L, Ivessa A, Ciruela F, Virág L, Haskó G, Kókai E. Cathepsin D interacts with adenosine A 2A receptors in mouse macrophages to modulate cell surface localization and inflammatory signaling. J Biol Chem 2022; 298:101888. [PMID: 35367412 PMCID: PMC9065627 DOI: 10.1016/j.jbc.2022.101888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 03/21/2022] [Accepted: 03/23/2022] [Indexed: 11/30/2022] Open
Abstract
Adenosine A2A receptor (A2AR)–dependent signaling in macrophages plays a key role in the regulation of inflammation. However, the processes regulating A2AR targeting to the cell surface and degradation in macrophages are incompletely understood. For example, the C-terminal domain of the A2AR and proteins interacting with it are known to regulate receptor recycling, although it is unclear what role potential A2AR-interacting partners have in macrophages. Here, we aimed to identify A2AR-interacting partners in macrophages that may effect receptor trafficking and activity. To this end, we performed a yeast two-hybrid screen using the C-terminal tail of A2AR as the “bait” and a macrophage expression library as the “prey.” We found that the lysosomal protease cathepsin D (CtsD) was a robust hit. The A2AR–CtsD interaction was validated in vitro and in cellular models, including RAW 264.7 and mouse peritoneal macrophage (IPMΦ) cells. We also demonstrated that the A2AR is a substrate of CtsD and that the blockade of CtsD activity increases the density and cell surface targeting of A2AR in macrophages. Conversely, we demonstrate that A2AR activation prompts the maturation and enzymatic activity of CtsD in macrophages. In summary, we conclude that CtsD is a novel A2AR-interacting partner and thus describe molecular and functional interplay that may be crucial for adenosine-mediated macrophage regulation in inflammatory processes.
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Affiliation(s)
- Adrienn Skopál
- Department of Medical Chemistry, Faculty of Medicine, University of Debrecen, Debrecen, Hungary; Doctoral School of Molecular Medicine, University of Debrecen, Debrecen, Hungary
| | - Tamás Kéki
- Department of Medical Chemistry, Faculty of Medicine, University of Debrecen, Debrecen, Hungary; Doctoral School of Molecular Medicine, University of Debrecen, Debrecen, Hungary
| | - Péter Á Tóth
- Department of Medical Chemistry, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Balázs Csóka
- Department of Anesthesiology, Columbia University, New York, New York, USA
| | - Balázs Koscsó
- Department of Pathology, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Zoltán H Németh
- Department of Anesthesiology, Columbia University, New York, New York, USA; Department of Surgery, Morristown Medical Center, Morristown, New Jersey, USA
| | - Luca Antonioli
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Andreas Ivessa
- Department of Cell Biology and Molecular Medicine, Cardiovascular Research Institute, Rutgers New Jersey Medical School, Newark, New Jersey, USA
| | - Francisco Ciruela
- Pharmacology Unit, Department of Pathology and Experimental Therapeutics, School of Medicine and Health Sciences, Institute of Neurosciences, University of Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain; Neuropharmacology and Pain Group, Neuroscience Program, Bellvitge Institute for Biomedical Research, L'Hospitalet de Llobregat, Barcelona, Spain
| | - László Virág
- Department of Medical Chemistry, Faculty of Medicine, University of Debrecen, Debrecen, Hungary; MTA-DE Cell Biology and Signaling Research Group, University of Debrecen, Debrecen, Hungary
| | - György Haskó
- Department of Anesthesiology, Columbia University, New York, New York, USA.
| | - Endre Kókai
- Department of Medical Chemistry, Faculty of Medicine, University of Debrecen, Debrecen, Hungary.
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Kotulova J, Lonova K, Kubickova A, Vrbkova J, Kourilova P, Hajduch M, Dzubak P. 2‑Cl‑IB‑MECA regulates the proliferative and drug resistance pathways, and facilitates chemosensitivity in pancreatic and liver cancer cell lines. Int J Mol Med 2022; 49:31. [PMID: 35039871 PMCID: PMC8788926 DOI: 10.3892/ijmm.2022.5086] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Accepted: 12/14/2021] [Indexed: 12/24/2022] Open
Abstract
Specific A3 adenosine receptor (A3AR) agonist, 2-chloro-N6-(3-iodobenzyl)-5′-N-methylcarboxamidoadenosine (2-Cl-IB-MECA), demonstrates anti-proliferative effects on various types of tumor. In the present study, the cytotoxicity of 2-Cl-IB-MECA was analyzed in a panel of tumor and non-tumor cell lines and its anticancer mechanisms in JoPaca-1 pancreatic and Hep-3B hepatocellular carcinoma cell lines were also investigated. Initially, decreased tumor cell proliferation, cell accumulation in the G1 phase and inhibition of DNA and RNA synthesis was found. Furthermore, western blot analysis showed decreased protein expression level of β-catenin, patched1 (Ptch1) and glioma-associated oncogene homolog zinc finger protein 1 (Gli1), which are components of the Wnt/β-catenin and Sonic hedgehog/Ptch/Gli transduction pathways. In concordance with these findings, the protein expression levels of cyclin D1 and c-Myc were reduced. Using a luciferase assay, it was revealed for the first time a decrease in β-catenin transcriptional activity, as an early event following 2-Cl-IB-MECA treatment. In addition, the protein expression levels of multidrug resistance-associated protein 1 and P-glycoprotein (P-gp) were reduced and the P-gp xenobiotic efflux function was also reduced. Next, the enhancing effects of 2-Cl-IB-MECA on the cytotoxicity of conventional chemotherapy was investigated. It was found that 2-Cl-IB-MECA enhanced carboplatin and doxorubicin cytotoxic effects in the JoPaca-1 and Hep-3B cell lines, and a greater synergy was found in the highly tumorigenic JoPaca-1 cell line. This provides a novel in vitro rationale for the utiliza- tion of 2-Cl-IB-MECA in combination with chemotherapeutic agents, not only for hepatocellular carcinoma, but also for pancreatic cancer. Other currently used conventional chemo- therapeutics, fluorouracil and gemcitabine, showed synergy only when combined with high doses of 2-Cl-IB-MECA. Notably, experiments with A3AR-specific antagonist, N-[9-Chloro-2-(2-furanyl)(1,2,4)-triazolo(1,5-c)quinazolin-5-yl] benzene acetamide, revealed that 2-Cl-IB-MECA had antitumor effects via both A3AR-dependent and -independent pathways. In conclusion, the present study identified novel antitumor mechanisms of 2-Cl-IB-MECA in pancreatic and hepatocellular carcinoma in vitro that further underscores the importance of A3AR agonists in cancer therapy.
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Affiliation(s)
- Jana Kotulova
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University Olomouc, 77900 Olomouc, Czech Republic
| | - Katerina Lonova
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University Olomouc, 77900 Olomouc, Czech Republic
| | - Agata Kubickova
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University Olomouc, 77900 Olomouc, Czech Republic
| | - Jana Vrbkova
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University Olomouc, 77900 Olomouc, Czech Republic
| | - Pavla Kourilova
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University Olomouc, 77900 Olomouc, Czech Republic
| | - Marian Hajduch
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University Olomouc, 77900 Olomouc, Czech Republic
| | - Petr Dzubak
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University Olomouc, 77900 Olomouc, Czech Republic
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Liston TE, Hama A, Boltze J, Poe RB, Natsume T, Hayashi I, Takamatsu H, Korinek WS, Lechleiter JD. Adenosine A1R/A3R (Adenosine A1 and A3 Receptor) Agonist AST-004 Reduces Brain Infarction in a Nonhuman Primate Model of Stroke. Stroke 2021; 53:238-248. [PMID: 34802248 DOI: 10.1161/strokeaha.121.036396] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
BACKGROUND AND PURPOSE Treatment with A1R/A3R (adenosine A1 and A3 receptor) agonists in rodent models of acute ischemic stroke results in significantly reduced lesion volume, indicating activation of adenosine A1R or A3R is cerebroprotective. However, dosing and timing required for cerebroprotection has yet to be established, and whether adenosine A1R/A3R activation will lead to cerebroprotection in a gyrencephalic species has yet to be determined. METHODS The current study used clinical study intervention timelines in a nonhuman primate model of transient, 4-hour middle cerebral artery occlusion to investigate a potential cerebroprotective effect of the dual adenosine A1R/A3R agonist AST-004. Bolus and then 22 hours intravenous infusion of AST-004 was initiated 2 hours after transient middle cerebral artery occlusion. Primary outcome measures included lesion volume, lesion growth kinetics, penumbra volume as well as initial pharmacokinetic-pharmacodynamic relationships measured up to 5 days after transient middle cerebral artery occlusion. Secondary outcome measures included physiological parameters and neurological function. RESULTS Administration of AST-004 resulted in rapid and statistically significant decreases in lesion growth rate and total lesion volume. In addition, penumbra volume decline over time was significantly less under AST-004 treatment compared with vehicle treatment. These changes correlated with unbound AST-004 concentrations in the plasma and cerebrospinal fluid as well as estimated brain A1R and A3R occupancy. No relevant changes in physiological parameters were observed during AST-004 treatment. CONCLUSIONS These findings suggest that administration of AST-004 and combined A1R/A3R agonism in the brain are efficacious pharmacological interventions in acute ischemic stroke and warrant further clinical evaluation.
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Affiliation(s)
- Theodore E Liston
- Astrocyte Pharmaceuticals Inc, Cambridge, MA (T.E.L., R.B.P., W.S.K.)
| | - Aldric Hama
- Hamamatsu Pharma Research Inc, Japan (A.H., I.H., T.N., H.T.)
| | - Johannes Boltze
- Department of Neuroscience, University of Warwick, United Kingdom (J.B.)
| | - Russell B Poe
- Astrocyte Pharmaceuticals Inc, Cambridge, MA (T.E.L., R.B.P., W.S.K.)
| | | | - Ikuo Hayashi
- Hamamatsu Pharma Research Inc, Japan (A.H., I.H., T.N., H.T.)
| | | | - William S Korinek
- Astrocyte Pharmaceuticals Inc, Cambridge, MA (T.E.L., R.B.P., W.S.K.)
| | - James D Lechleiter
- Department of Cell Systems and Anatomy, University of Texas Health San Antonio (J.D.L.)
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9
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Garcia-Garcia L, Olle L, Martin M, Roca-Ferrer J, Muñoz-Cano R. Adenosine Signaling in Mast Cells and Allergic Diseases. Int J Mol Sci 2021; 22:ijms22105203. [PMID: 34068999 PMCID: PMC8156042 DOI: 10.3390/ijms22105203] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 05/10/2021] [Accepted: 05/12/2021] [Indexed: 02/06/2023] Open
Abstract
Adenosine is a nucleoside involved in the pathogenesis of allergic diseases. Its effects are mediated through its binding to G protein-coupled receptors: A1, A2a, A2b and A3. The receptors differ in the type of G protein they recruit, in the effect on adenylyl cyclase (AC) activity and the downstream signaling pathway triggered. Adenosine can produce both an enhancement and an inhibition of mast cell degranulation, indicating that adenosine effects on these receptors is controversial and remains to be clarified. Depending on the study model, A1, A2b, and A3 receptors have shown anti- or pro-inflammatory activity. However, most studies reported an anti-inflammatory activity of A2a receptor. The precise knowledge of the adenosine mechanism of action may allow to develop more efficient therapies for allergic diseases by using selective agonist and antagonist against specific receptor subtypes.
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Affiliation(s)
- Lucia Garcia-Garcia
- Clinical and Experimental Respiratory Immunoallergy (IRCE), Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), 08036 Barcelona, Spain; (L.G.-G.); (L.O.); (M.M.); (J.R.-F.)
| | - Laia Olle
- Clinical and Experimental Respiratory Immunoallergy (IRCE), Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), 08036 Barcelona, Spain; (L.G.-G.); (L.O.); (M.M.); (J.R.-F.)
| | - Margarita Martin
- Clinical and Experimental Respiratory Immunoallergy (IRCE), Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), 08036 Barcelona, Spain; (L.G.-G.); (L.O.); (M.M.); (J.R.-F.)
- Biochemistry and Molecular Biology Unit, Biomedicine Department, Faculty of Medicine, University of Barcelona, 08036 Barcelona, Spain
- ARADyAL, Instituto de Salud Carlos III, 28220 Madrid, Spain
| | - Jordi Roca-Ferrer
- Clinical and Experimental Respiratory Immunoallergy (IRCE), Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), 08036 Barcelona, Spain; (L.G.-G.); (L.O.); (M.M.); (J.R.-F.)
| | - Rosa Muñoz-Cano
- Clinical and Experimental Respiratory Immunoallergy (IRCE), Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), 08036 Barcelona, Spain; (L.G.-G.); (L.O.); (M.M.); (J.R.-F.)
- ARADyAL, Instituto de Salud Carlos III, 28220 Madrid, Spain
- Allergy Section, Hospital Clinic, Universitat de Barcelona, 08036 Barcelona, Spain
- Correspondence: ; Tel.: +34-93-2275540
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10
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Macatangay BJC, Jackson EK, Abebe KZ, Comer D, Cyktor J, Klamar-Blain C, Borowski L, Gillespie DG, Mellors JW, Rinaldo CR, Riddler SA. A Randomized, Placebo-Controlled, Pilot Clinical Trial of Dipyridamole to Decrease Human Immunodeficiency Virus-Associated Chronic Inflammation. J Infect Dis 2021; 221:1598-1606. [PMID: 31282542 DOI: 10.1093/infdis/jiz344] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Accepted: 07/04/2019] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND Adenosine is a potent immunoregulatory nucleoside produced during inflammatory states to limit tissue damage. We hypothesized that dipyridamole, which inhibits cellular adenosine uptake, could raise the extracellular adenosine concentration and dampen chronic inflammation associated with human immunodeficiency virus (HIV) type 1. METHODS Virally suppressed participants receiving antiretroviral therapy were randomized 1:1 for 12 weeks of dipyridamole (100 mg 4 times a day) versus placebo capsules. All participants took open-label dipyridamole during weeks 12-24. Study end points included changes in markers of systemic inflammation (soluble CD163 and CD14, and interleukin 6) and levels of T-cell immune activation (HLA-DR+CD38+). RESULTS Of 40 participants who were randomized, 17 dipyridamole and 18 placebo recipients had baseline and week 12 data available for analyses. There were no significant changes in soluble markers, apart from a trend toward decreased levels of soluble CD163 levels (P = .09). There was a modest decrease in CD8+ T-cell activation (-17.53% change for dipyridamole vs +13.31% for placebo; P = .03), but the significance was lost in the pooled analyses (P = .058). Dipyridamole also reduced CD4+ T-cell activation (-11.11% change; P = .006) in the pooled analyses. In post hoc analysis, detectable plasma dipyridamole levels were associated with higher levels of inosine, an adenosine surrogate, and of cyclic adenosine monophosphate. CONCLUSION Dipyridamole increased extracellular adenosine levels and decreased T-cell activation significantly among persons with HIV-1 infection receiving virally suppressive therapy.
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Affiliation(s)
- Bernard J C Macatangay
- Department of Medicine, University of Pittsburgh School of Medicine, Pennsylvania.,Department of Infectious Diseases and Microbiology, University of Pittsburgh Graduate School of Public Health, Pennsylvania
| | - Edwin K Jackson
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pennsylvania
| | - Kaleab Z Abebe
- Department of Medicine, University of Pittsburgh School of Medicine, Pennsylvania
| | - Diane Comer
- Department of Medicine, University of Pittsburgh School of Medicine, Pennsylvania
| | - Joshua Cyktor
- Department of Medicine, University of Pittsburgh School of Medicine, Pennsylvania
| | - Cynthia Klamar-Blain
- Department of Medicine, University of Pittsburgh School of Medicine, Pennsylvania
| | - Luann Borowski
- Department of Infectious Diseases and Microbiology, University of Pittsburgh Graduate School of Public Health, Pennsylvania
| | - Delbert G Gillespie
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pennsylvania
| | - John W Mellors
- Department of Medicine, University of Pittsburgh School of Medicine, Pennsylvania.,Department of Infectious Diseases and Microbiology, University of Pittsburgh Graduate School of Public Health, Pennsylvania
| | - Charles R Rinaldo
- Department of Infectious Diseases and Microbiology, University of Pittsburgh Graduate School of Public Health, Pennsylvania.,Department of Pathology, University of Pittsburgh School of Medicine, Pennsylvania
| | - Sharon A Riddler
- Department of Medicine, University of Pittsburgh School of Medicine, Pennsylvania.,Department of Infectious Diseases and Microbiology, University of Pittsburgh Graduate School of Public Health, Pennsylvania
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11
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Ogawa A, Nagiri C, Shihoya W, Inoue A, Kawakami K, Hiratsuka S, Aoki J, Ito Y, Suzuki T, Suzuki T, Inoue T, Nureki O, Tanihara H, Tomizawa K, Wei FY. N 6-methyladenosine (m 6A) is an endogenous A3 adenosine receptor ligand. Mol Cell 2021; 81:659-674.e7. [PMID: 33472058 DOI: 10.1016/j.molcel.2020.12.038] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 09/15/2020] [Accepted: 12/24/2020] [Indexed: 02/06/2023]
Abstract
About 150 post-transcriptional RNA modifications have been identified in all kingdoms of life. During RNA catabolism, most modified nucleosides are resistant to degradation and are released into the extracellular space. In this study, we explored the physiological role of these extracellular modified nucleosides and found that N6-methyladenosine (m6A), widely recognized as an epigenetic mark in RNA, acts as a ligand for the human adenosine A3 receptor, for which it has greater affinity than unmodified adenosine. We used structural modeling to define the amino acids required for specific binding of m6A to the human A3 receptor. We also demonstrated that m6A was dynamically released in response to cytotoxic stimuli and facilitated type I allergy in vivo. Our findings implicate m6A as a signaling molecule capable of activating G protein-coupled receptors (GPCRs) and triggering pathophysiological responses, a previously unreported property of RNA modifications.
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Affiliation(s)
- Akiko Ogawa
- Department of Modomics Biology and Medicine, Institute of Development, Aging and Cancer (IDAC), Tohoku University, Sendai 980-8575, Japan; Department of Molecular Physiology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan; Department of Ophthalmology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
| | - Chisae Nagiri
- Department of Biological Sciences, Graduate School of Science, University of Tokyo, Tokyo, Japan
| | - Wataru Shihoya
- Department of Biological Sciences, Graduate School of Science, University of Tokyo, Tokyo, Japan
| | - Asuka Inoue
- Laboratory of Molecular and Cellular Biochemistry, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan; Advanced Research and Development Programs for Medical Innovation (PRIME), Japan Agency for Medical Research and Development (AMED), Tokyo, Japan; Advanced Research and Development Programs for Medical Innovation (LEAP), AMED, Tokyo, Japan
| | - Kouki Kawakami
- Laboratory of Molecular and Cellular Biochemistry, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan
| | - Suzune Hiratsuka
- Laboratory of Molecular and Cellular Biochemistry, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan
| | - Junken Aoki
- Advanced Research and Development Programs for Medical Innovation (LEAP), AMED, Tokyo, Japan; Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo, Japan
| | - Yasuhiro Ito
- Department of Ophthalmology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
| | - Takeo Suzuki
- Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, Tokyo, Japan
| | - Tsutomu Suzuki
- Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, Tokyo, Japan
| | - Toshihiro Inoue
- Department of Ophthalmology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
| | - Osamu Nureki
- Department of Biological Sciences, Graduate School of Science, University of Tokyo, Tokyo, Japan
| | | | - Kazuhito Tomizawa
- Department of Molecular Physiology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan; Center for Metabolic Regulation of Healthy Aging, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
| | - Fan-Yan Wei
- Department of Modomics Biology and Medicine, Institute of Development, Aging and Cancer (IDAC), Tohoku University, Sendai 980-8575, Japan; Department of Molecular Physiology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan; Precursory Research for Embryonic Science and Technology (PRESTO), Japan Science and Technology Agency (JST), Kawaguchi, Japan.
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12
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The Specificity of Downstream Signaling for A 1 and A 2AR Does Not Depend on the C-Terminus, Despite the Importance of This Domain in Downstream Signaling Strength. Biomedicines 2020; 8:biomedicines8120603. [PMID: 33322210 PMCID: PMC7764039 DOI: 10.3390/biomedicines8120603] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 12/07/2020] [Accepted: 12/09/2020] [Indexed: 11/17/2022] Open
Abstract
Recent efforts to determine the high-resolution crystal structures for the adenosine receptors (A1R and A2AR) have utilized modifications to the native receptors in order to facilitate receptor crystallization and structure determination. One common modification is a truncation of the unstructured C-terminus, which has been utilized for all the adenosine receptor crystal structures obtained to date. Ligand binding for this truncated receptor has been shown to be similar to full-length receptor for A2AR. However, the C-terminus has been identified as a location for protein-protein interactions that may be critical for the physiological function of these important drug targets. We show that variants with A2AR C-terminal truncations lacked cAMP-linked signaling compared to the full-length receptor constructs transfected into mammalian cells (HEK-293). In addition, we show that in a humanized yeast system, the absence of the full-length C-terminus affected downstream signaling using a yeast MAPK response-based fluorescence assay, though full-length receptors showed native-like G-protein coupling. To further study the G protein coupling, we used this humanized yeast platform to explore coupling to human-yeast G-protein chimeras in a cellular context. Although the C-terminus was essential for Gα protein-associated signaling, chimeras of A1R with a C-terminus of A2AR coupled to the A1R-specific Gα (i.e., Gαi1 versus Gαs). This surprising result suggests that the C-terminus is important in the signaling strength, but not specificity, of the Gα protein interaction. This result has further implications in drug discovery, both in enabling the experimental use of chimeras for ligand design, and in the cautious interpretation of structure-based drug design using truncated receptors.
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13
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Patinha D, Abreu C, Carvalho C, Cunha OM, Mota M, Afonso J, Sousa T, Albino-Teixeira A, Diniz C, Morato M. Adenosine A 2A and A 3 Receptors as Targets for the Treatment of Hypertensive-Diabetic Nephropathy. Biomedicines 2020; 8:biomedicines8110529. [PMID: 33238361 PMCID: PMC7700226 DOI: 10.3390/biomedicines8110529] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 11/11/2020] [Accepted: 11/17/2020] [Indexed: 12/14/2022] Open
Abstract
Diabetic nephropathy (DN) and hypertension are prime causes for end-stage renal disease (ESRD) that often coexist in patients, but are seldom studied in combination. Kidney adenosine levels are markedly increased in diabetes, and the expression and function of renal adenosine receptors are altered in experimental diabetes. The aim of this work is to explore the impact of endogenous and exogenous adenosine on the expression/distribution profile of its receptors along the nephron of hypertensive rats with experimentally-induced diabetes. Using spontaneously hypertensive (SHR) rats rendered diabetic with streptozotocin (STZ), we show that treatment of SHR-STZ rats with an agonist of adenosine receptors increases A2A immunoreactivity in superficial glomeruli (SG), proximal tubule (PCT), and distal tubule (DCT). Differently, treatment of SHR-STZ rats with a xanthinic antagonist of adenosine receptors decreases adenosine A3 immunoreactivity in SG, PCT, DCT, and collecting duct. There is no difference in the immunoreactivity against the adenosine A1 and A2B receptors between the experimental groups. The agonist of adenosine receptors ameliorates renal fibrosis, probably via A2A receptors, while the antagonist exacerbates it, most likely due to tonic activation of A3 receptors. The reduction in adenosine A3 immunoreactivity might be due to receptor downregulation in response to prolonged activation. Altogether, these results suggest an opposite regulation exerted by endogenous and exogenous adenosine upon the expression of its A2A and A3 receptors along the nephron of hypertensive diabetic rats, which has a functional impact and should be taken into account when considering novel therapeutic targets for hypertensive-diabetic nephropathy.
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Affiliation(s)
- Daniela Patinha
- Department of Biomedicine—Unit of Pharmacology and Therapeutics, Faculty of Medicine, University of Porto, 4200-450 Porto, Portugal; (D.P.); (J.A.); (T.S.); (A.A.-T.)
- The Institute of Biomedical and Clinical Science, Medical School, University of Exeter, EX4 4QJ Exeter, UK
| | - Carla Abreu
- LAQV@REQUIMTE, Laboratory of Pharmacology, Department of Drug Sciences, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal; (C.A.); (C.C.); (O.M.C.); (M.M.); (M.M.)
| | - Carla Carvalho
- LAQV@REQUIMTE, Laboratory of Pharmacology, Department of Drug Sciences, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal; (C.A.); (C.C.); (O.M.C.); (M.M.); (M.M.)
| | - Olga Mariana Cunha
- LAQV@REQUIMTE, Laboratory of Pharmacology, Department of Drug Sciences, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal; (C.A.); (C.C.); (O.M.C.); (M.M.); (M.M.)
| | - Mariana Mota
- LAQV@REQUIMTE, Laboratory of Pharmacology, Department of Drug Sciences, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal; (C.A.); (C.C.); (O.M.C.); (M.M.); (M.M.)
| | - Joana Afonso
- Department of Biomedicine—Unit of Pharmacology and Therapeutics, Faculty of Medicine, University of Porto, 4200-450 Porto, Portugal; (D.P.); (J.A.); (T.S.); (A.A.-T.)
- MedInUP—Center for Drug Discovery and Innovative Medicines, University of Porto, 4200-319 Porto, Portugal
| | - Teresa Sousa
- Department of Biomedicine—Unit of Pharmacology and Therapeutics, Faculty of Medicine, University of Porto, 4200-450 Porto, Portugal; (D.P.); (J.A.); (T.S.); (A.A.-T.)
- MedInUP—Center for Drug Discovery and Innovative Medicines, University of Porto, 4200-319 Porto, Portugal
| | - António Albino-Teixeira
- Department of Biomedicine—Unit of Pharmacology and Therapeutics, Faculty of Medicine, University of Porto, 4200-450 Porto, Portugal; (D.P.); (J.A.); (T.S.); (A.A.-T.)
- MedInUP—Center for Drug Discovery and Innovative Medicines, University of Porto, 4200-319 Porto, Portugal
| | - Carmen Diniz
- LAQV@REQUIMTE, Laboratory of Pharmacology, Department of Drug Sciences, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal; (C.A.); (C.C.); (O.M.C.); (M.M.); (M.M.)
- Correspondence:
| | - Manuela Morato
- LAQV@REQUIMTE, Laboratory of Pharmacology, Department of Drug Sciences, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal; (C.A.); (C.C.); (O.M.C.); (M.M.); (M.M.)
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14
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Zhang D, Wang Y, Lin H, Sun Y, Wang M, Jia Y, Yu X, Jiang H, Xu W, Sun JP, Xu Z. Function and therapeutic potential of G protein-coupled receptors in epididymis. Br J Pharmacol 2020; 177:5489-5508. [PMID: 32901914 DOI: 10.1111/bph.15252] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2020] [Revised: 08/08/2020] [Accepted: 09/03/2020] [Indexed: 12/14/2022] Open
Abstract
Infertility rates for both females and males have increased continuously in recent years. Currently, effective treatments for male infertility with defined mechanisms or targets are still lacking. G protein-coupled receptors (GPCRs) are the largest class of drug targets, but their functions and the implications for the therapeutic development for male infertility largely remain elusive. Nevertheless, recent studies have shown that several members of the GPCR superfamily play crucial roles in the maintenance of ion-water homeostasis of the epididymis, development of the efferent ductules, formation of the blood-epididymal barrier and maturation of sperm. Knowledge of the functions, genetic variations and working mechanisms of such GPCRs, along with the drugs and ligands relevant to their specific functions, provide future directions and a great arsenal for new developments in the treatment of male infertility.
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Affiliation(s)
- Daolai Zhang
- Department of Pharmaceutical Sciences, Binzhou Medical University, Yantai, China.,Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, School of Medicine, Shandong University, Jinan, China
| | - Yanfei Wang
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Qingdao, China
| | - Hui Lin
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, School of Medicine, Shandong University, Jinan, China
| | - Yujing Sun
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, School of Medicine, Shandong University, Jinan, China
| | - Mingwei Wang
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, School of Medicine, Shandong University, Jinan, China
| | - Yingli Jia
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, Peking University, Beijing, China
| | - Xiao Yu
- Department of Physiology, School of Medicine, Shandong University, Jinan, China
| | - Hui Jiang
- Department of Urology, Peking University Third Hospital, Beijing, China.,Department of Reproductive Medicine Center, Peking University Third Hospital, Beijing, China
| | - Wenming Xu
- Joint Laboratory of Reproductive Medicine, SCU-CUHK, Key Laboratory of Obstetric, Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, Sichuan University West China Second University Hospital, Chengdu, China
| | - Jin-Peng Sun
- Department of Pharmaceutical Sciences, Binzhou Medical University, Yantai, China.,Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, School of Medicine, Shandong University, Jinan, China.,Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, Peking University, Beijing, China
| | - Zhigang Xu
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Qingdao, China.,Shandong Provincial Collaborative Innovation Center of Cell Biology, Shandong Normal University, Jinan, China
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15
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Thibeault PE, Ramachandran R. Biased signaling in platelet G-protein coupled receptors. Can J Physiol Pharmacol 2020; 99:255-269. [PMID: 32846106 DOI: 10.1139/cjpp-2020-0149] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Platelets are small megakaryocyte-derived, anucleate, disk-like structures that play an outsized role in human health and disease. Both a decrease in the number of platelets and a variety of platelet function disorders result in petechiae or bleeding that can be life threatening. Conversely, the inappropriate activation of platelets, within diseased blood vessels, remains the leading cause of death and morbidity by affecting heart attacks and stroke. The fine balance of the platelet state in healthy individuals is controlled by a number of receptor-mediated signaling pathways that allow the platelet to rapidly respond and maintain haemostasis. G-protein coupled receptors (GPCRs) are particularly important regulators of platelet function. Here we focus on the major platelet-expressed GPCRs and discuss the roles of downstream signaling pathways (e.g., different G-protein subtypes or β-arrestin) in regulating the different phases of the platelet activation. Further, we consider the potential for selectively targeting signaling pathways that may contribute to platelet responses in disease through development of biased agonists. Such selective targeting of GPCR-mediated signaling pathways by drugs, often referred to as biased signaling, holds promise in delivering therapeutic interventions that do not present significant side effects, especially in finely balanced physiological systems such as platelet activation in haemostasis.
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Affiliation(s)
- Pierre E Thibeault
- Department of Physiology and Pharmacology, University of Western Ontario, 1151 Richmond Street, London, ON N6A5C1, Canada.,Department of Physiology and Pharmacology, University of Western Ontario, 1151 Richmond Street, London, ON N6A5C1, Canada
| | - Rithwik Ramachandran
- Department of Physiology and Pharmacology, University of Western Ontario, 1151 Richmond Street, London, ON N6A5C1, Canada.,Department of Physiology and Pharmacology, University of Western Ontario, 1151 Richmond Street, London, ON N6A5C1, Canada
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16
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Martí Navia A, Dal Ben D, Lambertucci C, Spinaci A, Volpini R, Marques-Morgado I, Coelho JE, Lopes LV, Marucci G, Buccioni M. Adenosine Receptors as Neuroinflammation Modulators: Role of A 1 Agonists and A 2A Antagonists. Cells 2020; 9:cells9071739. [PMID: 32708189 PMCID: PMC7409197 DOI: 10.3390/cells9071739] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 07/17/2020] [Indexed: 01/07/2023] Open
Abstract
The pathological condition of neuroinflammation is caused by the activation of the neuroimmune cells astrocytes and microglia. The autacoid adenosine seems to be an important neuromodulator in this condition. Its main receptors involved in the neuroinflammation modulation are A1AR and A2AAR. Evidence suggests that A1AR activation produces a neuroprotective effect and A2AARs block prevents neuroinflammation. The aim of this work is to elucidate the effects of these receptors in neuroinflammation using the partial agonist 2'-dCCPA (2-chloro-N6-cyclopentyl-2'-deoxyadenosine) (C1 KiA1AR = 550 nM, KiA2AAR = 24,800 nM, and KiA3AR = 5560 nM, α = 0.70, EC50A1AR = 832 nM) and the newly synthesized in house compound 8-chloro-9-ethyl-2-phenethoxyadenine (C2 KiA2AAR = 0.75 nM; KiA1AR = 17 nM and KiA3AR = 227 nM, IC50A2AAR = 251 nM unpublished results). The experiments were performed in in vitro and in in vivo models of neuroinflammation. Results showed that C1 was able to prevent the inflammatory effect induced by cytokine cocktail (TNF-α, IL-1β, and IFN-γ) while C2 possess both anti-inflammatory and antioxidant properties, counteracting both neuroinflammation in mixed glial cells and in an animal model of neuroinflammation. In conclusion, C2 is a potential candidate for neuroinflammation therapy.
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Affiliation(s)
- Aleix Martí Navia
- School of Pharmacy, Medicinal Chemistry Unit, University of Camerino, 62032 Camerino (MC), Italy; (A.M.N.); (D.D.B.); (C.L.); (A.S.); (R.V.); (M.B.)
| | - Diego Dal Ben
- School of Pharmacy, Medicinal Chemistry Unit, University of Camerino, 62032 Camerino (MC), Italy; (A.M.N.); (D.D.B.); (C.L.); (A.S.); (R.V.); (M.B.)
| | - Catia Lambertucci
- School of Pharmacy, Medicinal Chemistry Unit, University of Camerino, 62032 Camerino (MC), Italy; (A.M.N.); (D.D.B.); (C.L.); (A.S.); (R.V.); (M.B.)
| | - Andrea Spinaci
- School of Pharmacy, Medicinal Chemistry Unit, University of Camerino, 62032 Camerino (MC), Italy; (A.M.N.); (D.D.B.); (C.L.); (A.S.); (R.V.); (M.B.)
| | - Rosaria Volpini
- School of Pharmacy, Medicinal Chemistry Unit, University of Camerino, 62032 Camerino (MC), Italy; (A.M.N.); (D.D.B.); (C.L.); (A.S.); (R.V.); (M.B.)
| | - Inês Marques-Morgado
- Instituto de Medicina Molecular, Faculdade de Medicina de Lisboa, Universidade de Lisboa, 1649-028 Lisbon, Portugal; (I.M.-M.); (J.E.C.); (L.V.L.)
| | - Joana E. Coelho
- Instituto de Medicina Molecular, Faculdade de Medicina de Lisboa, Universidade de Lisboa, 1649-028 Lisbon, Portugal; (I.M.-M.); (J.E.C.); (L.V.L.)
| | - Luísa V. Lopes
- Instituto de Medicina Molecular, Faculdade de Medicina de Lisboa, Universidade de Lisboa, 1649-028 Lisbon, Portugal; (I.M.-M.); (J.E.C.); (L.V.L.)
| | - Gabriella Marucci
- School of Pharmacy, Medicinal Chemistry Unit, University of Camerino, 62032 Camerino (MC), Italy; (A.M.N.); (D.D.B.); (C.L.); (A.S.); (R.V.); (M.B.)
- Correspondence: ; Tel.: +39-073-7402-223
| | - Michela Buccioni
- School of Pharmacy, Medicinal Chemistry Unit, University of Camerino, 62032 Camerino (MC), Italy; (A.M.N.); (D.D.B.); (C.L.); (A.S.); (R.V.); (M.B.)
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17
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Kanzato N, Nakachi K, Naka T, Mochizuki S, Miyamae Y, Okada Y. Parkinson's disease therapy with Istradefylline and blood biomarkers of epigenetics. ACTA ACUST UNITED AC 2020. [DOI: 10.1111/ncn3.12415] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Naomi Kanzato
- Department of Neurology Okinawa Prefectural Southern Medical Center & Children's Medical Center Okinawa Japan
| | - Kou Nakachi
- Department of Neurology Okinawa Prefectural Southern Medical Center & Children's Medical Center Okinawa Japan
| | - Taro Naka
- Department of Neurology Okinawa Prefectural Southern Medical Center & Children's Medical Center Okinawa Japan
| | - Satsuki Mochizuki
- Department of Surgery National Defense Medical College Saitama Japan
| | - Yuka Miyamae
- Department of Pathophysiology for Locomotive and Neoplastic Diseases Juntendo University Graduate School of Medicine Tokyo Japan
| | - Yasunori Okada
- Department of Pathophysiology for Locomotive and Neoplastic Diseases Juntendo University Graduate School of Medicine Tokyo Japan
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18
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Exercise-Induced Adaptations to the Mouse Striatal Adenosine System. Neural Plast 2020; 2020:5859098. [PMID: 32399024 PMCID: PMC7204111 DOI: 10.1155/2020/5859098] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 12/18/2019] [Accepted: 12/27/2019] [Indexed: 12/13/2022] Open
Abstract
Adenosine acts as a key regulator of striatum activity, in part, through the antagonistic modulation of dopamine activity. Exercise can increase adenosine activity in the brain, which may impair dopaminergic functions in the striatum. Therefore, long-term repeated bouts of exercise may subsequently generate plasticity in striatal adenosine systems in a manner that promotes dopaminergic activity. This study investigated the effects of long-term voluntary wheel running on adenosine 1 (A1R), adenosine 2A (A2AR), dopamine 1 (D1R), and dopamine 2 (D2R) receptor protein expression in adult mouse dorsal and ventral striatum structures using immunohistochemistry. In addition, equilibrative nucleoside transporter 1 (ENT1) protein expression was examined after wheel running, as ENT1 regulates the bidirectional flux of adenosine between intra- and extracellular space. The results suggest that eight weeks of running wheel access spared age-related increases of A1R and A2AR protein concentrations across the dorsal and ventral striatal structures. Wheel running mildly reduced ENT1 protein levels in ventral striatum subregions. Moreover, wheel running mildly increased D2R protein density within striatal subregions in the dorsal medial striatum, nucleus accumbens core, and the nucleus accumbens shell. However, D1R protein expression in the striatum was unchanged by wheel running. These data suggest that exercise promotes adaptations to striatal adenosine systems. Exercise-reduced A1R and A2AR and exercise-increased D2R protein levels may contribute to improved dopaminergic signaling in the striatum. These findings may have implications for cognitive and behavioral processes, as well as motor and psychiatric diseases that involve the striatum.
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Accuracy and Precision of the Receptorial Responsiveness Method (RRM) in the Quantification of A 1 Adenosine Receptor Agonists. Int J Mol Sci 2019; 20:ijms20246264. [PMID: 31842299 PMCID: PMC6940880 DOI: 10.3390/ijms20246264] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 12/07/2019] [Accepted: 12/09/2019] [Indexed: 12/17/2022] Open
Abstract
The receptorial responsiveness method (RRM) is a procedure that is based on a simple nonlinear regression while using a model with two variables (X, Y) and (at least) one parameter to be determined (cx). The model of RRM describes the co-action of two agonists that consume the same response capacity (due to the use of the same postreceptorial signaling in a biological system). While using RRM, uniquely, an acute increase in the concentration of an agonist (near the receptors) can be quantified (as cx), via evaluating E/c curves that were constructed with the same or another agonist in the same system. As this measurement is sensitive to the implementation of the curve fitting, the goal of the present study was to test RRM by combining different ways and setting options, namely: individual vs. global fitting, ordinary vs. robust fitting, and three weighting options (no weighting vs. weighting by 1/Y2 vs. weighting by 1/SD2). During the testing, RRM was used to estimate the known concentrations of stable synthetic A1 adenosine receptor agonists in isolated, paced guinea pig left atria. The estimates were then compared to the known agonist concentrations (to assess the accuracy of RRM); furthermore, the 95% confidence limits of the best-fit values were also considered (to evaluate the precision of RRM). It was found that, although the global fitting offered the most convenient way to perform RRM, the best estimates were provided by the individual fitting without any weighting, almost irrespective of the fact whether ordinary or robust fitting was chosen.
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Soave M, Kellam B, Woolard J, Briddon SJ, Hill SJ. NanoBiT Complementation to Monitor Agonist-Induced Adenosine A 1 Receptor Internalization. SLAS DISCOVERY 2019; 25:186-194. [PMID: 31583945 PMCID: PMC6974774 DOI: 10.1177/2472555219880475] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Receptor internalization in response to prolonged agonist treatment is an
important regulator of G protein–coupled receptor (GPCR) function. The adenosine
A1 receptor (A1AR) is one of the adenosine receptor
family of GPCRs, and evidence for its agonist-induced internalization is
equivocal. The recently developed NanoBiT technology uses split NanoLuc
Luciferase to monitor changes in protein interactions. We have modified the
human A1AR on the N-terminus with the small high-affinity HiBiT tag.
In the presence of the large NanoLuc subunit (LgBiT), complementation occurs,
reconstituting a full-length functional NanoLuc Luciferase. Here, we have used
complemented luminescence to monitor the internalization of the A1AR
in living HEK293 cells. Agonist treatment resulted in a robust decrease in
cell-surface luminescence, indicating an increase in A1AR
internalization. These responses were inhibited by the A1AR-selective
antagonist 1,3-dipropyl-8-cyclopentylxanthine (DPCPX), with an antagonist
affinity that closely matched that measured using ligand binding with a
fluorescent A1 receptor antagonist (CA200645). The agonist potencies
for inducing A1AR internalization were very similar to the affinities
previously determined by ligand binding, suggesting little or no amplification
of the internalization response. By complementing the HiBiT tag to exogenous
purified LgBiT, it was also possible to perform NanoBRET ligand-binding
experiments using HiBiT–A1AR. This study demonstrates the use of
NanoBiT technology to monitor internalization of the A1AR and offers
the potential to combine these experiments with NanoBRET ligand-binding
assays.
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Affiliation(s)
- Mark Soave
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham Medical School, Queen's Medical Centre, Nottingham, UK.,Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, The Midlands, UK
| | - Barrie Kellam
- Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, The Midlands, UK.,School of Pharmacy, Centre for Biomolecular Sciences, University of Nottingham, Nottingham, UK
| | - Jeanette Woolard
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham Medical School, Queen's Medical Centre, Nottingham, UK.,Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, The Midlands, UK
| | - Stephen J Briddon
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham Medical School, Queen's Medical Centre, Nottingham, UK.,Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, The Midlands, UK
| | - Stephen J Hill
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham Medical School, Queen's Medical Centre, Nottingham, UK.,Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, The Midlands, UK
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Blockade of the Adenosine A 3 Receptor Attenuates Caspase 1 Activation in Renal Tubule Epithelial Cells and Decreases Interleukins IL-1β and IL-18 in Diabetic Rats. Int J Mol Sci 2019; 20:ijms20184531. [PMID: 31540220 PMCID: PMC6770662 DOI: 10.3390/ijms20184531] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 08/10/2019] [Accepted: 08/26/2019] [Indexed: 12/11/2022] Open
Abstract
Diabetic nephropathy (DN) is the main cause of end-stage renal disease, which remains incurable. The progression of DN is associated with progressive and irreversible renal fibrosis and also high levels of adenosine. Our aim was to evaluate the effects of ADORA3 antagonism on renal injury in streptozotocin-induced diabetic rats. An ADORA3 antagonist that was administered in diabetic rats greatly inhibited the levels of inflammatory interleukins IL-1β and IL-18, meanwhile when adenosine deaminase was administered, there was a non-selective attenuation of the inflammatory mediators IL-1β, IL-18, IL-6, and induction of IL-10. The ADORA3 antagonist attenuated the high glucose-induced activation of caspase 1 in HK2 cells in vitro. Additionally, ADORA3 antagonisms blocked the increase in caspase 1 and the nuclear localization of NFκB in the renal tubular epithelium of diabetic rats, both events that are involved in regulating the production and activation of IL-1β and IL-18. The effects of the A3 receptor antagonist resulted in the attenuation of kidney injury, as evidenced by decreased levels of the pro-fibrotic marker α-SMA at histological levels and the restoration of proteinuria in diabetic rats. We conclude that ADORA3 antagonism represents a potential therapeutic target that mechanistically works through the selective blockade of the NLRP3 inflammasome.
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22
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Yu Y, Nguyen DT, Jiang J. G protein-coupled receptors in acquired epilepsy: Druggability and translatability. Prog Neurobiol 2019; 183:101682. [PMID: 31454545 DOI: 10.1016/j.pneurobio.2019.101682] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 07/09/2019] [Accepted: 08/15/2019] [Indexed: 02/06/2023]
Abstract
As the largest family of membrane proteins in the human genome, G protein-coupled receptors (GPCRs) constitute the targets of more than one-third of all modern medicinal drugs. In the central nervous system (CNS), widely distributed GPCRs in neuronal and nonneuronal cells mediate numerous essential physiological functions via regulating neurotransmission at the synapses. Whereas their abnormalities in expression and activity are involved in various neuropathological processes. CNS conditions thus remain highly represented among the indications of GPCR-targeted agents. Mounting evidence from a large number of animal studies suggests that GPCRs play important roles in the regulation of neuronal excitability associated with epilepsy, a common CNS disease afflicting approximately 1-2% of the population. Surprisingly, none of the US Food and Drug Administration (FDA)-approved (>30) antiepileptic drugs (AEDs) suppresses seizures through acting on GPCRs. This disparity raises concerns about the translatability of these preclinical findings and the druggability of GPCRs for seizure disorders. The currently available AEDs intervene seizures predominantly through targeting ion channels and have considerable limitations, as they often cause unbearable adverse effects, fail to control seizures in over 30% of patients, and merely provide symptomatic relief. Thus, identifying novel molecular targets for epilepsy is highly desired. Herein, we focus on recent progresses in understanding the comprehensive roles of several GPCR families in seizure generation and development of acquired epilepsy. We also dissect current hurdles hindering translational efforts in developing GPCRs as antiepileptic and/or antiepileptogenic targets and discuss the counteracting strategies that might lead to a potential cure for this debilitating CNS condition.
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Affiliation(s)
- Ying Yu
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN 38163, USA; Drug Discovery Center, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Davis T Nguyen
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN 38163, USA; Drug Discovery Center, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Jianxiong Jiang
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN 38163, USA; Drug Discovery Center, University of Tennessee Health Science Center, Memphis, TN 38163, USA; Department of Anatomy and Neurobiology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN 38163, USA; Neuroscience Institute, University of Tennessee Health Science Center, Memphis, TN 38163, USA.
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23
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Jacobson KA, Tosh DK, Jain S, Gao ZG. Historical and Current Adenosine Receptor Agonists in Preclinical and Clinical Development. Front Cell Neurosci 2019; 13:124. [PMID: 30983976 PMCID: PMC6447611 DOI: 10.3389/fncel.2019.00124] [Citation(s) in RCA: 128] [Impact Index Per Article: 25.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Accepted: 03/13/2019] [Indexed: 12/22/2022] Open
Abstract
Adenosine receptors (ARs) function in the body’s response to conditions of pathology and stress associated with a functional imbalance, such as in the supply and demand of energy/oxygen/nutrients. Extracellular adenosine concentrations vary widely to raise or lower the basal activation of four subtypes of ARs. Endogenous adenosine can correct an energy imbalance during hypoxia and other stress, for example, by slowing the heart rate by A1AR activation or increasing the blood supply to heart muscle by the A2AAR. Moreover, exogenous AR agonists, antagonists, or allosteric modulators can be applied for therapeutic benefit, and medicinal chemists working toward that goal have reported thousands of such agents. Thus, numerous clinical trials have ensued, using promising agents to modulate adenosinergic signaling, most of which have not succeeded. Currently, short-acting, parenteral agonists, adenosine and Regadenoson, are the only AR agonists approved for human use. However, new concepts and compounds are currently being developed and applied toward preclinical and clinical evaluation, and initial results are encouraging. This review focuses on key compounds as AR agonists and positive allosteric modulators (PAMs) for disease treatment or diagnosis. AR agonists for treating inflammation, pain, cancer, non-alcoholic steatohepatitis, angina, sickle cell disease, ischemic conditions and diabetes have been under development. Multiple clinical trials with two A3AR agonists are ongoing.
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Affiliation(s)
- Kenneth A Jacobson
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Dilip K Tosh
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Shanu Jain
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Zhan-Guo Gao
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, United States
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24
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Zhou Z, Matsumoto T, Jankowski V, Pernow J, Mustafa SJ, Duncker DJ, Merkus D. Uridine adenosine tetraphosphate and purinergic signaling in cardiovascular system: An update. Pharmacol Res 2019; 141:32-45. [PMID: 30553823 PMCID: PMC6685433 DOI: 10.1016/j.phrs.2018.12.009] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Revised: 10/26/2018] [Accepted: 12/12/2018] [Indexed: 02/07/2023]
Abstract
Uridine adenosine tetraphosphate (Up4A), biosynthesized by activation of vascular endothelial growth factor receptor (VEGFR) 2, was initially identified as a potent endothelium-derived vasoconstrictor in perfused rat kidney. Subsequently, the effect of Up4A on vascular tone regulation was intensively investigated in arteries isolated from different vascular beds in rodents including rat pulmonary arteries, aortas, mesenteric and renal arteries as well as mouse aortas, in which Up4A produces vascular contraction. In contrast, Up4A produces vascular relaxation in porcine coronary small arteries and rat aortas. Intravenous infusion of Up4A into conscious rats or mice decreases blood pressure, and intravenous bolus injection of Up4A into anesthetized mice increases coronary blood flow, indicating an overall vasodilator influence in vivo. Although Up4A is the first dinucleotide described that contains both purine and pyrimidine moieties, its cardiovascular effects are exerted mainly through activation of purinergic receptors. These effects not only encompass regulation of vascular tone, but also endothelial angiogenesis, smooth muscle cell proliferation and migration, and vascular calcification. Furthermore, this review discusses a potential role for Up4A in cardiovascular pathophysiology, as plasma levels of Up4A are elevated in juvenile hypertensive patients and Up4A-mediated vascular purinergic signaling changes in cardiovascular disease such as hypertension, diabetes, atherosclerosis and myocardial infarction. Better understanding the vascular effect of the novel dinucleotide Up4A and the purinergic signaling mechanisms mediating its effects will enhance its potential as target for treatment of cardiovascular disease.
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Affiliation(s)
- Zhichao Zhou
- Division of Cardiology, Department of Medicine, Karolinska University Hospital, Karolinska Institutet, Stockholm, Sweden.
| | - Takayuki Matsumoto
- Department of Physiology and Morphology, Institute of Medicinal Chemistry, Hoshi University, Tokyo, Japan
| | - Vera Jankowski
- RWTH-Aachen, Institute for Molecular Cardiovascular Research, Aachen, Germany
| | - John Pernow
- Division of Cardiology, Department of Medicine, Karolinska University Hospital, Karolinska Institutet, Stockholm, Sweden
| | - S Jamal Mustafa
- Department of Physiology, Pharmacology & Neuroscience, Center for Cardiovascular and Respiratory Sciences, Clinical and Translational Science Institute, West Virginia University, Morgantown, WV, United States
| | - Dirk J Duncker
- Division of Experimental Cardiology, Department of Cardiology, Thoraxcenter, Erasmus University Medical Center, Rotterdam, the Netherlands
| | - Daphne Merkus
- Division of Experimental Cardiology, Department of Cardiology, Thoraxcenter, Erasmus University Medical Center, Rotterdam, the Netherlands
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25
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Lordkipanidzé M, Hvas AM, Harrison P. Clinical Tests of Platelet Function. Platelets 2019. [DOI: 10.1016/b978-0-12-813456-6.00033-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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26
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Jacobson KA, Tosh DK, Jain S, Gao ZG. Historical and Current Adenosine Receptor Agonists in Preclinical and Clinical Development. Front Cell Neurosci 2019. [PMID: 30983976 DOI: 10.3389/fncel.2019.00124/bibtex] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023] Open
Abstract
Adenosine receptors (ARs) function in the body's response to conditions of pathology and stress associated with a functional imbalance, such as in the supply and demand of energy/oxygen/nutrients. Extracellular adenosine concentrations vary widely to raise or lower the basal activation of four subtypes of ARs. Endogenous adenosine can correct an energy imbalance during hypoxia and other stress, for example, by slowing the heart rate by A1AR activation or increasing the blood supply to heart muscle by the A2AAR. Moreover, exogenous AR agonists, antagonists, or allosteric modulators can be applied for therapeutic benefit, and medicinal chemists working toward that goal have reported thousands of such agents. Thus, numerous clinical trials have ensued, using promising agents to modulate adenosinergic signaling, most of which have not succeeded. Currently, short-acting, parenteral agonists, adenosine and Regadenoson, are the only AR agonists approved for human use. However, new concepts and compounds are currently being developed and applied toward preclinical and clinical evaluation, and initial results are encouraging. This review focuses on key compounds as AR agonists and positive allosteric modulators (PAMs) for disease treatment or diagnosis. AR agonists for treating inflammation, pain, cancer, non-alcoholic steatohepatitis, angina, sickle cell disease, ischemic conditions and diabetes have been under development. Multiple clinical trials with two A3AR agonists are ongoing.
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Affiliation(s)
- Kenneth A Jacobson
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Dilip K Tosh
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Shanu Jain
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Zhan-Guo Gao
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, United States
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27
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Sek K, Mølck C, Stewart GD, Kats L, Darcy PK, Beavis PA. Targeting Adenosine Receptor Signaling in Cancer Immunotherapy. Int J Mol Sci 2018; 19:ijms19123837. [PMID: 30513816 PMCID: PMC6321150 DOI: 10.3390/ijms19123837] [Citation(s) in RCA: 110] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Revised: 11/27/2018] [Accepted: 11/27/2018] [Indexed: 02/07/2023] Open
Abstract
The immune system plays a major role in the surveillance and control of malignant cells, with the presence of tumor infiltrating lymphocytes (TILs) correlating with better patient prognosis in multiple tumor types. The development of ‘checkpoint blockade’ and adoptive cellular therapy has revolutionized the landscape of cancer treatment and highlights the potential of utilizing the patient’s own immune system to eradicate cancer. One mechanism of tumor-mediated immunosuppression that has gained attention as a potential therapeutic target is the purinergic signaling axis, whereby the production of the purine nucleoside adenosine in the tumor microenvironment can potently suppress T and NK cell function. The production of extracellular adenosine is mediated by the cell surface ectoenzymes CD73, CD39, and CD38 and therapeutic agents have been developed to target these as well as the downstream adenosine receptors (A1R, A2AR, A2BR, A3R) to enhance anti-tumor immune responses. This review will discuss the role of adenosine and adenosine receptor signaling in tumor and immune cells with a focus on their cell-specific function and their potential as targets in cancer immunotherapy.
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Affiliation(s)
- Kevin Sek
- Cancer Immunology Program, Peter MacCallum Cancer Centre, East Melbourne, Victoria 3000, Australia.
- Sir Peter MacCallum Department of Oncology, The University of Melbourne, 3010 Parkville, Australia.
| | - Christina Mølck
- Department of Pathology, University of Melbourne, Parkville 3010, Australia.
| | - Gregory D Stewart
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences and Department of Pharmacology, Monash University, Parkville 3052, Australia.
| | - Lev Kats
- Cancer Immunology Program, Peter MacCallum Cancer Centre, East Melbourne, Victoria 3000, Australia.
- Sir Peter MacCallum Department of Oncology, The University of Melbourne, 3010 Parkville, Australia.
| | - Phillip K Darcy
- Cancer Immunology Program, Peter MacCallum Cancer Centre, East Melbourne, Victoria 3000, Australia.
- Sir Peter MacCallum Department of Oncology, The University of Melbourne, 3010 Parkville, Australia.
- Department of Pathology, University of Melbourne, Parkville 3010, Australia.
- Department of Immunology, Monash University, Clayton 3052, Australia.
| | - Paul A Beavis
- Cancer Immunology Program, Peter MacCallum Cancer Centre, East Melbourne, Victoria 3000, Australia.
- Sir Peter MacCallum Department of Oncology, The University of Melbourne, 3010 Parkville, Australia.
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28
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Cognitive impairments by alcohol and sleep deprivation indicate trait characteristics and a potential role for adenosine A 1 receptors. Proc Natl Acad Sci U S A 2018; 115:8009-8014. [PMID: 30012607 DOI: 10.1073/pnas.1803770115] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Trait-like differences in cognitive performance after sleep loss put some individuals more at risk than others, the basis of such disparities remaining largely unknown. Similarly, interindividual differences in impairment in response to alcohol intake have been observed. We tested whether performance impairments due to either acute or chronic sleep loss can be predicted by an individual's vulnerability to acute alcohol intake. Also, we used positron emission tomography (PET) to test whether acute alcohol infusion results in an up-regulation of cerebral A1 adenosine receptors (A1ARs), similar to the changes previously observed following sleep deprivation. Sustained attention in the psychomotor vigilance task (PVT) was tested in 49 healthy volunteers (26 ± 5 SD years; 15 females) (i) under baseline conditions: (ii) after ethanol intake, and after either (iii) total sleep deprivation (TSD; 35 hours awake; n = 35) or (iv) partial sleep deprivation (PSD; four nights with 5 hours scheduled sleep; n = 14). Ethanol- versus placebo-induced changes in cerebral A1AR availability were measured in 10 healthy male volunteers (31 ± 9 years) with [18F]8-cyclopentyl-3-(3-fluoropropyl)-1-propylxanthine (CPFPX) PET. Highly significant correlations between the performance impairments induced by ethanol and sleep deprivation were found for various PVT parameters, including mean speed (TSD, r = 0.62; PSD, r = 0.84). A1AR availability increased up to 26% in several brain regions with ethanol infusion. Our studies revealed individual trait characteristics for being either vulnerable or resilient to both alcohol and to sleep deprivation. Both interventions induce gradual increases in cerebral A1AR availability, pointing to a potential common molecular response mechanism.
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29
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Vecchio EA, Baltos JA, Nguyen ATN, Christopoulos A, White PJ, May LT. New paradigms in adenosine receptor pharmacology: allostery, oligomerization and biased agonism. Br J Pharmacol 2018; 175:4036-4046. [PMID: 29679502 DOI: 10.1111/bph.14337] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Revised: 03/29/2018] [Accepted: 04/04/2018] [Indexed: 12/17/2022] Open
Abstract
Adenosine receptors are a family of GPCRs containing four subtypes (A1 , A2A , A2B and A3 receptors), all of which bind the ubiquitous nucleoside adenosine. These receptors play an important role in physiology and pathophysiology and therefore represent attractive drug targets for a range of conditions. The theoretical framework surrounding drug action at adenosine receptors now extends beyond the notion of prototypical agonism and antagonism to encompass more complex pharmacological concepts. New paradigms include allostery, in which ligands bind a topographically distinct receptor site from that of the endogenous agonist, homomeric or heteromeric interactions across receptor oligomers and biased agonism, that is, ligand-dependent differential intracellular signalling. This review provides a concise overview of allostery, oligomerization and biased agonism at adenosine receptors and outlines how these paradigms may enhance future drug discovery endeavours focussed on the development of novel therapeutic agents acting at adenosine receptors. LINKED ARTICLES This article is part of a themed section on Molecular Pharmacology of GPCRs. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v175.21/issuetoc.
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Affiliation(s)
- Elizabeth A Vecchio
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne, VIC, Australia.,Department of Pharmacology, Monash University, Melbourne, VIC, Australia
| | - Jo-Anne Baltos
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne, VIC, Australia.,Department of Pharmacology, Monash University, Melbourne, VIC, Australia
| | - Anh T N Nguyen
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne, VIC, Australia.,Department of Pharmacology, Monash University, Melbourne, VIC, Australia
| | - Arthur Christopoulos
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne, VIC, Australia.,Department of Pharmacology, Monash University, Melbourne, VIC, Australia
| | - Paul J White
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne, VIC, Australia
| | - Lauren T May
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne, VIC, Australia.,Department of Pharmacology, Monash University, Melbourne, VIC, Australia
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30
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Ganesana M, Venton BJ. Early changes in transient adenosine during cerebral ischemia and reperfusion injury. PLoS One 2018; 13:e0196932. [PMID: 29799858 PMCID: PMC5969733 DOI: 10.1371/journal.pone.0196932] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Accepted: 04/23/2018] [Indexed: 12/20/2022] Open
Abstract
Adenosine is an important neuromodulator in the central nervous system, and tissue adenosine levels increase during ischemic events, attenuating excitotoxic neuronal injury. Recently, our lab developed an electrochemical fast-scan cyclic voltammetry (FSCV) method that identified rapid, spontaneous changes in adenosine concentrations that last only about 3 seconds. Here, we investigated the effects of cerebral ischemia and reperfusion on the concentration and frequency of transient adenosine release in the caudate-putamen. In anesthetized rats, data were collected for four hours: two hours of normoxia, 30 min of cerebral ischemia induced by bilateral common carotid artery occlusion, and 90 min of reperfusion. Transient adenosine release was increased during the cerebral ischemia period and remained elevated during reperfusion. The total number of adenosine transients increased by 52% during cerebral ischemia and reperfusion compared to normoxia. The concentration of adenosine per event did not increase but the cumulative adenosine concentration during cerebral ischemia and reperfusion increased by 53% because of the higher frequency of events. Further, we evaluated the role of A2A antagonist, SCH442416, a putative neuroprotective agent to affect adenosine transients. SCH442416 significantly decreased the transient frequency during cerebral ischemia-reperfusion by 27% and the cumulative concentration by 31%. Our results demonstrate that this mode of rapid adenosine release increases during early cerebral ischemia-reperfusion injury. Rapid adenosine release could provide fast, local neuromodulation and neuroprotection during cerebral ischemia.
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Affiliation(s)
| | - B Jill Venton
- Department of Chemistry and Neuroscience Graduate Program, University of Virginia, Charlottesville, VA, United States of America
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Bessa-Gonçalves M, Bragança B, Martins-Dias E, Correia-de-Sá P, Fontes-Sousa AP. Is the adenosine A 2B 'biased' receptor a valuable target for the treatment of pulmonary arterial hypertension? Drug Discov Today 2018; 23:1285-1292. [PMID: 29747005 DOI: 10.1016/j.drudis.2018.05.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Revised: 03/25/2018] [Accepted: 05/02/2018] [Indexed: 12/12/2022]
Abstract
Pulmonary arterial hypertension (PAH) is a maladaptive disorder characterized by increased pulmonary vascular resistance leading to right ventricular failure and death. Adenosine released by injured tissues, such as the lung and heart, influences tissue remodeling through the activation of adenosine receptors. Evidence regarding activation of the low-affinity A2BAR by adenosine points towards pivotal roles of this receptor in processes associated with both acute and chronic lung diseases. Conflicting results exist concerning the beneficial or detrimental roles of the A2B 'biased' receptor in right ventricular failure secondary to PAH. In this review, we discuss the pros and cons of manipulating A2BARs as a putative therapeutic target in PAH.
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Affiliation(s)
- Mafalda Bessa-Gonçalves
- Laboratório de Farmacologia e Neurobiologia, Centro de Investigação Farmacológica e Inovação Medicamentosa (MedInUP), Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto (ICBAS-UP), Porto, Portugal
| | - Bruno Bragança
- Laboratório de Farmacologia e Neurobiologia, Centro de Investigação Farmacológica e Inovação Medicamentosa (MedInUP), Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto (ICBAS-UP), Porto, Portugal
| | - Eduardo Martins-Dias
- Laboratório de Farmacologia e Neurobiologia, Centro de Investigação Farmacológica e Inovação Medicamentosa (MedInUP), Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto (ICBAS-UP), Porto, Portugal
| | - Paulo Correia-de-Sá
- Laboratório de Farmacologia e Neurobiologia, Centro de Investigação Farmacológica e Inovação Medicamentosa (MedInUP), Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto (ICBAS-UP), Porto, Portugal
| | - Ana Patrícia Fontes-Sousa
- Laboratório de Farmacologia e Neurobiologia, Centro de Investigação Farmacológica e Inovação Medicamentosa (MedInUP), Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto (ICBAS-UP), Porto, Portugal.
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Chen PZ, He WJ, Zhu ZR, E GJ, Xu G, Chen DW, Gao YQ. Adenosine A 2A receptor involves in neuroinflammation-mediated cognitive decline through activating microglia under acute hypobaric hypoxia. Behav Brain Res 2018; 347:99-107. [PMID: 29501623 DOI: 10.1016/j.bbr.2018.02.038] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Revised: 02/26/2018] [Accepted: 02/26/2018] [Indexed: 01/05/2023]
Abstract
Hypobaric hypoxia (HH) at high altitudes leads to a wide range of cognitive impairments which can handicap human normal activities and performances. However, the underlying mechanism is still unclear. Adenosine A2A receptors (A2ARs) of the brain are pivotal to synaptic plasticity and cognition. Besides, insult-induced up-regulation of A2AR regulates neuroinflammation and therefore induces brain damages in various neuropathological processes. The present study was designed to determine whether A2AR-mediate neuroinflammation involves in cognitive impairments under acute HH. A2AR knock-out and wild-type male mice were exposed to a simulated altitude of 8000 m for 7 consecutive days in a hypobaric chamber and simultaneously received behavioral tests including Morris water maze test and open filed test. A2AR expression, the activation of microglia and the production of TNF-α were evaluated in the hippocampus by immunohistochemistry and ELISA, respectively. Behavioral tests showed that acute HH exposure caused the dysfunction of spatial memory and mood, while genetic inactivation of A2AR attenuated the impairment of spatial memory but not that of mood. Double-labeled immunofluorescence showed that A2ARs were mainly expressed on microglia and up-regulated in the hippocampus of acute HH model mice. Acute HH also induced the accumulation of microglia and increased production of TNF-α in the hippocampus, which could be markedly inhibited by A2AR inactivation. These findings indicate that microglia-mediated neuroinflammation triggered by A2AR activation involves in acute HH-induced spatial memory impairment and that A2AR could be a new target for the pharmacotherapy of cognitive dysfunction at high altitudes.
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Affiliation(s)
- Peng-Zhi Chen
- Institute of Medicine and Hygienic Equipment for High Altitude Region, College of High Altitude Military Medicine, Third Military Medical University, Chongqing, China; Key Laboratory of High Altitude Environmental Medicine, Third Military Medical University, Ministry of Education, Chongqing, China; Key Laboratory of High Altitude Medicine, PLA, Chongqing, China
| | - Wen-Juan He
- Department of Pathophysiology and High Altitude Pathology, College of High Altitude Military Medicine, Third Military Medical University, Chongqing, China
| | - Zhi-Ru Zhu
- Department of Developmental Neuropsychology, School of Psychology, Third Military Medical University, Chongqing, China
| | - Guo-Ji E
- Institute of Medicine and Hygienic Equipment for High Altitude Region, College of High Altitude Military Medicine, Third Military Medical University, Chongqing, China; Key Laboratory of High Altitude Environmental Medicine, Third Military Medical University, Ministry of Education, Chongqing, China; Key Laboratory of High Altitude Medicine, PLA, Chongqing, China
| | - Gang Xu
- Institute of Medicine and Hygienic Equipment for High Altitude Region, College of High Altitude Military Medicine, Third Military Medical University, Chongqing, China; Key Laboratory of High Altitude Environmental Medicine, Third Military Medical University, Ministry of Education, Chongqing, China; Key Laboratory of High Altitude Medicine, PLA, Chongqing, China
| | - De-Wei Chen
- Department of Pathophysiology and High Altitude Pathology, College of High Altitude Military Medicine, Third Military Medical University, Chongqing, China
| | - Yu-Qi Gao
- Institute of Medicine and Hygienic Equipment for High Altitude Region, College of High Altitude Military Medicine, Third Military Medical University, Chongqing, China; Key Laboratory of High Altitude Environmental Medicine, Third Military Medical University, Ministry of Education, Chongqing, China; Key Laboratory of High Altitude Medicine, PLA, Chongqing, China.
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Storme J, Cannaert A, Van Craenenbroeck K, Stove CP. Molecular dissection of the human A 3 adenosine receptor coupling with β-arrestin2. Biochem Pharmacol 2018; 148:298-307. [PMID: 29309765 DOI: 10.1016/j.bcp.2018.01.008] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Accepted: 01/03/2018] [Indexed: 02/07/2023]
Abstract
Besides classical G protein coupling, G protein-coupled receptors (GPCRs) are nowadays well known to show significant signalling via other adaptor proteins, such as β-arrestin2 (βarr2). The elucidation of the molecular mechanism of the GPCR-βarr2 interaction is a prerequisite for the structure-activity based design of biased ligands, which introduces a new chapter in drug discovery. The general mechanism of the interaction is believed to rely on phosphorylation sites, exposed upon agonist binding. However, it is not known whether this mechanism is universal throughout the GPCR family or if GPCR-specific patterns are involved. In recent years, promising orally active agonists for the human A3 adenosine receptor (A3AR), a GPCR highly expressed in inflammatory and cancer cells, have been evaluated in clinical trials for the treatment of rheumatoid arthritis, psoriasis, and hepatocellular carcinoma. In this study, the effect of cytoplasmic modifications of the A3AR on βarr2 recruitment was evaluated in transiently transfected HEK293T cells, using a live-cell split-reporter system (NanoBit®, Promega), based on the structural complementation of NanoLuc luciferase, allowing real-time βarr2 monitoring. The A3AR-selective reference agonist 2-Cl-IB-MECA yielded a robust, concentration dependent (5 nM-1 µM) recruitment of βarr2 (logEC50: -7.798 ± 0.076). The role of putative phosphorylation sites, located in the C-terminal part and cytoplasmic loops, and the role of the 'DRY' motif was evaluated. It was shown that the A3AR C-terminus was dispensable for βarr2 recruitment. This contrasts with studies in the past for the rat A3AR, which pointed at crucial C-terminal phosphorylation sites. When combining truncation of the A3AR with modification of the 'DRY' motif to 'AAY', the βarr2 recruitment was drastically reduced. Recruitment could be partly rescued by back-mutation to 'NQY', or by extending the C-terminus again. In conclusion, other parts of the human A3AR, either cytosolic or exposed upon receptor activation, rather than the C-terminus alone, are responsible for βarr2 recruitment in a complementary or synergistic way.
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Affiliation(s)
- Jolien Storme
- Laboratory of Toxicology, Department of Bioanalysis, Faculty of Pharmaceutical Sciences, Ghent University, Ottergemsesteenweg 460, 9000 Ghent, Belgium
| | - Annelies Cannaert
- Laboratory of Toxicology, Department of Bioanalysis, Faculty of Pharmaceutical Sciences, Ghent University, Ottergemsesteenweg 460, 9000 Ghent, Belgium
| | - Kathleen Van Craenenbroeck
- Laboratory of Toxicology, Department of Bioanalysis, Faculty of Pharmaceutical Sciences, Ghent University, Ottergemsesteenweg 460, 9000 Ghent, Belgium
| | - Christophe P Stove
- Laboratory of Toxicology, Department of Bioanalysis, Faculty of Pharmaceutical Sciences, Ghent University, Ottergemsesteenweg 460, 9000 Ghent, Belgium.
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Leiva A, Guzmán-Gutiérrez E, Contreras-Duarte S, Fuenzalida B, Cantin C, Carvajal L, Salsoso R, Gutiérrez J, Pardo F, Sobrevia L. Adenosine receptors: Modulators of lipid availability that are controlled by lipid levels. Mol Aspects Med 2017; 55:26-44. [DOI: 10.1016/j.mam.2017.01.007] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2016] [Revised: 01/25/2017] [Accepted: 01/25/2017] [Indexed: 12/20/2022]
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Fuentes E, Fuentes M, Caballero J, Palomo I, Hinz S, El-Tayeb A, Müller CE. Adenosine A 2A receptor agonists with potent antiplatelet activity. Platelets 2017; 29:292-300. [PMID: 28504052 DOI: 10.1080/09537104.2017.1306043] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Selected adenosine A2A receptor agonists (PSB-15826, PSB-12404, and PSB-16301) have been evaluated as new antiplatelet agents. In addition, radioligand-binding studies and receptor-docking experiments were performed in order to explain their differential biological effects on a molecular level. Among the tested adenosine derivatives, PSB-15826 was the most potent compound to inhibit platelet aggregation (EC50 0.32 ± 0.05 µmol/L) and platelet P-selectin cell-surface localization (EC50 0.062 ± 0.2 µmol/L), and to increase intraplatelets cAMP levels (EC50 0.24 ± 0.01 µmol/L). The compound was more active than CGS21680 (EC50 0.97±0.07 µmol/L) and equipotent to NECA (EC50 0.31 ± 0.05 µmol/L) in platelet aggregation induced by ADP. In contrast to the results from cAMP assays, Ki values determined in radioligand-binding studies were not predictive of the A2A agonists' antiplatelet activity. Docking studies revealed the key molecular determinants of this new family of adenosine A2A receptor agonists: differences in activities are related to π-stacking interactions between the ligands and the residue His264 in the extracellular loop of the adenosine A2A receptor which may result in increased residence times. In conclusion, these results provide an improved understanding of the requirements of antiplatelet adenosine A2A receptor agonists.
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Affiliation(s)
- Eduardo Fuentes
- a Platelet Research Laboratory, Department of Clinical Biochemistry and Immunohematology, Faculty of Health Sciences , Interdisciplinary Excellence Research Program on Healthy Aging (PIEI-ES), Universidad de Talca , Talca , Chile.,b Núcleo Científico Multidisciplinario , Universidad de Talca , Talca , Chile
| | - Manuel Fuentes
- a Platelet Research Laboratory, Department of Clinical Biochemistry and Immunohematology, Faculty of Health Sciences , Interdisciplinary Excellence Research Program on Healthy Aging (PIEI-ES), Universidad de Talca , Talca , Chile
| | - Julio Caballero
- c Centro de Bioinformatica y Simulacion Molecular (CBSM) , Universidad de Talca , Talca , Chile
| | - Iván Palomo
- a Platelet Research Laboratory, Department of Clinical Biochemistry and Immunohematology, Faculty of Health Sciences , Interdisciplinary Excellence Research Program on Healthy Aging (PIEI-ES), Universidad de Talca , Talca , Chile
| | - Sonja Hinz
- d PharmaCenter Bonn , Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn , Bonn , Germany
| | - Ali El-Tayeb
- d PharmaCenter Bonn , Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn , Bonn , Germany
| | - Christa E Müller
- d PharmaCenter Bonn , Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn , Bonn , Germany
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Piirainen H, Taura J, Kursula P, Ciruela F, Jaakola VP. Calcium modulates calmodulin/α-actinin 1 interaction with and agonist-dependent internalization of the adenosine A 2A receptor. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2017; 1864:674-686. [PMID: 28130124 DOI: 10.1016/j.bbamcr.2017.01.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Revised: 01/14/2017] [Accepted: 01/23/2017] [Indexed: 10/20/2022]
Abstract
Adenosine receptors are G protein-coupled receptors that sense extracellular adenosine to transmit intracellular signals. One of the four adenosine receptor subtypes, the adenosine A2A receptor (A2AR), has an exceptionally long intracellular C terminus (A2AR-ct) that mediates interactions with a large array of proteins, including calmodulin and α-actinin. Here, we aimed to ascertain the α-actinin 1/calmodulin interplay whilst binding to A2AR and the role of Ca2+ in this process. First, we studied the A2AR-α-actinin 1 interaction by means of native polyacrylamide gel electrophoresis, isothermal titration calorimetry, and surface plasmon resonance, using purified recombinant proteins. α-Actinin 1 binds the A2AR-ct through its distal calmodulin-like domain in a Ca2+-independent manner with a dissociation constant of 5-12μM, thus showing an ~100 times lower affinity compared to the A2AR-calmodulin/Ca2+ complex. Importantly, calmodulin displaced α-actinin 1 from the A2AR-ct in a Ca2+-dependent fashion, disrupting the A2AR-α-actinin 1 complex. Finally, we assessed the impact of Ca2+ on A2AR internalization in living cells, a function operated by the A2AR-α-actinin 1 complex. Interestingly, while Ca2+ influx did not affect constitutive A2AR endocytosis, it abolished agonist-dependent internalization. In addition, we demonstrated that the A2AR/α-actinin interaction plays a pivotal role in receptor internalization and function. Overall, our results suggest that the interplay of A2AR with calmodulin and α-actinin 1 is fine-tuned by Ca2+, a fact that might power agonist-mediated receptor internalization and function.
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Affiliation(s)
- Henni Piirainen
- Faculty of Biochemistry and Molecular Medicine, Biocenter Oulu, University of Oulu, Finland
| | - Jaume Taura
- Unitat de Farmacologia, Departament Patologia i Terapèutica Experimental, Facultat de Medicina, IDIBELL, Universitat de Barcelona, Spain; Institut de Neurociències, Universitat de Barcelona, Spain
| | - Petri Kursula
- Faculty of Biochemistry and Molecular Medicine, Biocenter Oulu, University of Oulu, Finland; Department of Biomedicine, University of Bergen, Norway
| | - Francisco Ciruela
- Unitat de Farmacologia, Departament Patologia i Terapèutica Experimental, Facultat de Medicina, IDIBELL, Universitat de Barcelona, Spain; Institut de Neurociències, Universitat de Barcelona, Spain.
| | - Veli-Pekka Jaakola
- Faculty of Biochemistry and Molecular Medicine, Biocenter Oulu, University of Oulu, Finland.
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37
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Cunha RA. How does adenosine control neuronal dysfunction and neurodegeneration? J Neurochem 2016; 139:1019-1055. [PMID: 27365148 DOI: 10.1111/jnc.13724] [Citation(s) in RCA: 301] [Impact Index Per Article: 37.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Revised: 05/23/2016] [Accepted: 06/23/2016] [Indexed: 12/11/2022]
Abstract
The adenosine modulation system mostly operates through inhibitory A1 (A1 R) and facilitatory A2A receptors (A2A R) in the brain. The activity-dependent release of adenosine acts as a brake of excitatory transmission through A1 R, which are enriched in glutamatergic terminals. Adenosine sharpens salience of information encoding in neuronal circuits: high-frequency stimulation triggers ATP release in the 'activated' synapse, which is locally converted by ecto-nucleotidases into adenosine to selectively activate A2A R; A2A R switch off A1 R and CB1 receptors, bolster glutamate release and NMDA receptors to assist increasing synaptic plasticity in the 'activated' synapse; the parallel engagement of the astrocytic syncytium releases adenosine further inhibiting neighboring synapses, thus sharpening the encoded plastic change. Brain insults trigger a large outflow of adenosine and ATP, as a danger signal. A1 R are a hurdle for damage initiation, but they desensitize upon prolonged activation. However, if the insult is near-threshold and/or of short-duration, A1 R trigger preconditioning, which may limit the spread of damage. Brain insults also up-regulate A2A R, probably to bolster adaptive changes, but this heightens brain damage since A2A R blockade affords neuroprotection in models of epilepsy, depression, Alzheimer's, or Parkinson's disease. This initially involves a control of synaptotoxicity by neuronal A2A R, whereas astrocytic and microglia A2A R might control the spread of damage. The A2A R signaling mechanisms are largely unknown since A2A R are pleiotropic, coupling to different G proteins and non-canonical pathways to control the viability of glutamatergic synapses, neuroinflammation, mitochondria function, and cytoskeleton dynamics. Thus, simultaneously bolstering A1 R preconditioning and preventing excessive A2A R function might afford maximal neuroprotection. The main physiological role of the adenosine modulation system is to sharp the salience of information encoding through a combined action of adenosine A2A receptors (A2A R) in the synapse undergoing an alteration of synaptic efficiency with an increased inhibitory action of A1 R in all surrounding synapses. Brain insults trigger an up-regulation of A2A R in an attempt to bolster adaptive plasticity together with adenosine release and A1 R desensitization; this favors synaptotocity (increased A2A R) and decreases the hurdle to undergo degeneration (decreased A1 R). Maximal neuroprotection is expected to result from a combined A2A R blockade and increased A1 R activation. This article is part of a mini review series: "Synaptic Function and Dysfunction in Brain Diseases".
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Affiliation(s)
- Rodrigo A Cunha
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,FMUC-Faculty of Medicine, University of Coimbra, Coimbra, Portugal
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Heterologous, PKC-Mediated Desensitization of Human Histamine H3 Receptors Expressed in CHO-K1 Cells. Neurochem Res 2016; 41:2415-24. [PMID: 27350581 DOI: 10.1007/s11064-016-1954-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 05/06/2016] [Accepted: 05/11/2016] [Indexed: 12/11/2022]
Abstract
Desensitization is a major mechanism to regulate the functional response of G protein-coupled receptors. In this work we studied whether the human histamine H3 receptor of 445 amino acids (hH3R445) experiences heterologous desensitization mediated by PKC activation. Bioinformatic analysis indicated the presence of Serine and Threonine residues susceptible of PKC-mediated phosphorylation on the third intracellular loop and the carboxyl terminus of the hH3R445. In CHO-K1 cells stably transfected with the hH3R445 direct PKC activation by phorbol 12-myristate 13-acetate (TPA, 200 nM) abolished H3R-mediated inhibition of forskolin-stimulated cAMP accumulation. Activation of endogenous purinergic receptors by ATP (adenosine 5'-triphosphate, 10 μM) increased the free calcium intracellular concentration ([Ca(2+)]i) confirming their coupling to phospholipase C stimulation. Incubation with ATP also abolished H3R-mediated inhibition of forskolin-induced cAMP accumulation, and this effect was prevented by the PKC inhibitors Ro-31-8220 and Gö-6976. Pre-incubation with TPA or ATP reduced H3R-mediated stimulation of [(35)S]-GTPγS binding to membranes from CHO-K1-hH3R445 cells by 39.7 and 54.2 %, respectively, with no change in the agonist potency, and the effect was prevented by either Ro-31-8220 or Gö-6976. Exposure to ATP or TPA also resulted in the loss of cell surface H3Rs (-30.4 and -45.1 %) as evaluated by [(3)H]-NMHA binding to intact cells. These results indicate that the hH3R445 undergoes heterologous desensitization upon activation of receptors coupled to PKC stimulation.
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Kim DG, Bynoe MS. A2A adenosine receptor modulates drug efflux transporter P-glycoprotein at the blood-brain barrier. J Clin Invest 2016; 126:1717-33. [PMID: 27043281 PMCID: PMC4855938 DOI: 10.1172/jci76207] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Accepted: 02/18/2016] [Indexed: 11/17/2022] Open
Abstract
The blood-brain barrier (BBB) protects the brain from toxic substances within the peripheral circulation. It maintains brain homeostasis and is a hurdle for drug delivery to the CNS to treat neurodegenerative diseases, including Alzheimer's disease and brain tumors. The drug efflux transporter P-glycoprotein (P-gp) is highly expressed on brain endothelial cells and blocks the entry of most drugs delivered to the brain. Here, we show that activation of the A2A adenosine receptor (AR) with an FDA-approved A2A AR agonist (Lexiscan) rapidly and potently decreased P-gp expression and function in a time-dependent and reversible manner. We demonstrate that downmodulation of P-gp expression and function coincided with chemotherapeutic drug accumulation in brains of WT mice and in primary mouse and human brain endothelial cells, which serve as in vitro BBB models. Lexiscan also potently downregulated the expression of BCRP1, an efflux transporter that is highly expressed in the CNS vasculature and other tissues. Finally, we determined that multiple pathways, including MMP9 cleavage and ubiquitinylation, mediated P-gp downmodulation. Based on these data, we propose that A2A AR activation on BBB endothelial cells offers a therapeutic window that can be fine-tuned for drug delivery to the brain and has potential as a CNS drug-delivery technology.
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MESH Headings
- ATP Binding Cassette Transporter, Subfamily B/biosynthesis
- ATP Binding Cassette Transporter, Subfamily B/genetics
- ATP Binding Cassette Transporter, Subfamily G, Member 2/biosynthesis
- ATP Binding Cassette Transporter, Subfamily G, Member 2/blood
- ATP Binding Cassette Transporter, Subfamily G, Member 2/genetics
- Adenosine A2 Receptor Agonists/pharmacology
- Animals
- Blood-Brain Barrier/metabolism
- Cell Line
- Endothelial Cells/metabolism
- Gene Expression Regulation
- Humans
- Matrix Metalloproteinase 9/genetics
- Matrix Metalloproteinase 9/metabolism
- Mice
- Neoplasm Proteins/blood
- Neoplasm Proteins/genetics
- Proteolysis/drug effects
- Purines/pharmacology
- Pyrazoles/pharmacology
- Receptor, Adenosine A2A/genetics
- Receptor, Adenosine A2A/metabolism
- Ubiquitination/drug effects
- Ubiquitination/genetics
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Elnozahi NA, AlQot HE, Mohy El-Din MM, Bistawroos AE, Abou Zeit-Har MS. Modulation of dopamine-mediated facilitation at the neuromuscular junction of Wistar rats: A role for adenosine A1/A2A receptors and P2 purinoceptors. Neuroscience 2016; 326:45-55. [PMID: 27060487 DOI: 10.1016/j.neuroscience.2016.04.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Revised: 03/31/2016] [Accepted: 04/01/2016] [Indexed: 11/28/2022]
Abstract
This study aims to understand how dopamine and the neuromodulators, adenosine and adenosine triphosphate (ATP) modulate neuromuscular transmission. Adenosine and ATP are well-recognized for their regulatory effects on dopamine in the central nervous system. However, if similar interactions occur at the neuromuscular junction is unknown. We hypothesize that the activation of adenosine A1/A2A and/or P2 purinoceptors may influence the action of dopamine on neuromuscular transmission. Using the rat phrenic nerve hemi-diaphragm, we assessed the influence of dopamine, adenosine and ATP on the height of nerve-evoked muscle twitches. We investigated how the selective blockade of adenosine A1 receptors (2.5nM DPCPX), adenosine A2A receptors (50nM CSC) and P2 purinoceptors (100μM suramin) modified the effects of dopamine. Dopamine alone increased indirect muscle contractions while adenosine and ATP either enhanced or depressed nerve-evoked muscle twitches in a concentration-dependent manner. The facilitatory effects of 256μM dopamine were significantly reduced to 29.62±2.79% or 53.69±5.45% in the presence of DPCPX or CSC, respectively, relative to 70.03±1.57% with dopamine alone. Alternatively, the action of 256μM dopamine was potentiated from 70.03±1.57, in the absence of suramin, to 86.83±4.36%, in the presence of suramin. It can be concluded that the activation of adenosine A1 and A2A receptors and P2 purinoceptors potentially play a central role in the regulation of dopamine effects at the neuromuscular junction. Clinically this study offers new insights for the indirect manipulation of neuromuscular transmission for the treatment of disorders characterized by motor dysfunction.
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Affiliation(s)
- Neveen A Elnozahi
- Department of Pharmacology & Toxicology, Faculty of Pharmacy, Alexandria University, Azarita, P.O. Box: 21521, Alexandria, Egypt
| | - Hadir E AlQot
- Department of Pharmacology & Toxicology, Faculty of Pharmacy, Alexandria University, Azarita, P.O. Box: 21521, Alexandria, Egypt.
| | - Mahmoud M Mohy El-Din
- Department of Pharmacology & Toxicology, Faculty of Pharmacy, Alexandria University, Azarita, P.O. Box: 21521, Alexandria, Egypt
| | - Azza E Bistawroos
- Department of Pharmacology & Toxicology, Faculty of Pharmacy, Alexandria University, Azarita, P.O. Box: 21521, Alexandria, Egypt
| | - Mohamed S Abou Zeit-Har
- Department of Pharmacology & Toxicology, Faculty of Pharmacy, Alexandria University, Azarita, P.O. Box: 21521, Alexandria, Egypt
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41
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Li P, Rial D, Canas PM, Yoo JH, Li W, Zhou X, Wang Y, van Westen GJ, Payen MP, Augusto E, Gonçalves N, Tomé AR, Li Z, Wu Z, Hou X, Zhou Y, IJzerman AP, Boyden ES, Cunha RA, Qu J, Chen JF. Optogenetic activation of intracellular adenosine A2A receptor signaling in the hippocampus is sufficient to trigger CREB phosphorylation and impair memory. Mol Psychiatry 2015; 20:1339-49. [PMID: 25687775 PMCID: PMC4539301 DOI: 10.1038/mp.2014.182] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Revised: 10/28/2014] [Accepted: 11/12/2014] [Indexed: 11/26/2022]
Abstract
Human and animal studies have converged to suggest that caffeine consumption prevents memory deficits in aging and Alzheimer's disease through the antagonism of adenosine A2A receptors (A2ARs). To test if A2AR activation in the hippocampus is actually sufficient to impair memory function and to begin elucidating the intracellular pathways operated by A2AR, we have developed a chimeric rhodopsin-A2AR protein (optoA2AR), which retains the extracellular and transmembrane domains of rhodopsin (conferring light responsiveness and eliminating adenosine-binding pockets) fused to the intracellular loop of A2AR to confer specific A2AR signaling. The specificity of the optoA2AR signaling was confirmed by light-induced selective enhancement of cAMP and phospho-mitogen-activated protein kinase (p-MAPK) (but not cGMP) levels in human embryonic kidney 293 (HEK293) cells, which was abolished by a point mutation at the C terminal of A2AR. Supporting its physiological relevance, optoA2AR activation and the A2AR agonist CGS21680 produced similar activation of cAMP and p-MAPK signaling in HEK293 cells, of p-MAPK in the nucleus accumbens and of c-Fos/phosphorylated-CREB (p-CREB) in the hippocampus, and similarly enhanced long-term potentiation in the hippocampus. Remarkably, optoA2AR activation triggered a preferential p-CREB signaling in the hippocampus and impaired spatial memory performance, while optoA2AR activation in the nucleus accumbens triggered MAPK signaling and modulated locomotor activity. This shows that the recruitment of intracellular A2AR signaling in the hippocampus is sufficient to trigger memory dysfunction. Furthermore, the demonstration that the biased A2AR signaling and functions depend on intracellular A2AR loops prompts the possibility of targeting the intracellular A2AR-interacting partners to selectively control different neuropsychiatric behaviors.
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Affiliation(s)
- Ping Li
- Department of Neurology and Pharmacology, Boston University School of Medicine, Boston, MA 02118
- Molecular Biology Center, Research Institute of Surgery and Daping Hospital, Third Military Medical University, Chongqing, China
| | - Daniel Rial
- CNC – Center for Neuroscience and Cell Biology, University of Coimbra, Portugal
| | - Paula M. Canas
- CNC – Center for Neuroscience and Cell Biology, University of Coimbra, Portugal
| | - Ji-Hoon Yoo
- Department of Neurology and Pharmacology, Boston University School of Medicine, Boston, MA 02118
| | - Wei Li
- Department of Neurology and Pharmacology, Boston University School of Medicine, Boston, MA 02118
- Molecular Biology Center, Research Institute of Surgery and Daping Hospital, Third Military Medical University, Chongqing, China
| | - Xiangtian Zhou
- School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical College Wenzhou, Zhejiang, China
| | - Yumei Wang
- Department of Neurology and Pharmacology, Boston University School of Medicine, Boston, MA 02118
| | | | - Marie-Pierre Payen
- Department of Neurology and Pharmacology, Boston University School of Medicine, Boston, MA 02118
| | - Elisabete Augusto
- Department of Neurology and Pharmacology, Boston University School of Medicine, Boston, MA 02118
- CNC – Center for Neuroscience and Cell Biology, University of Coimbra, Portugal
- Department of Life Sciences, Faculty of Sciences and Technology, University of Coimbra, Portugal
| | - Nélio Gonçalves
- CNC – Center for Neuroscience and Cell Biology, University of Coimbra, Portugal
| | - Angelo R. Tomé
- CNC – Center for Neuroscience and Cell Biology, University of Coimbra, Portugal
- Department of Life Sciences, Faculty of Sciences and Technology, University of Coimbra, Portugal
| | - Zhihui Li
- School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical College Wenzhou, Zhejiang, China
| | - Zhongnan Wu
- School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical College Wenzhou, Zhejiang, China
| | - Xianhua Hou
- Department of Neurology and Pharmacology, Boston University School of Medicine, Boston, MA 02118
| | - Yuanguo Zhou
- Molecular Biology Center, Research Institute of Surgery and Daping Hospital, Third Military Medical University, Chongqing, China
| | - Ad P. IJzerman
- Leiden Academic Centre for Drug Research, Leiden University, Leiden, the Netherlands
| | - Edward S. Boyden
- MIT Media Lab, MIT McGovern Institute, Departments of Biological Engineering and Brain and Cognitive Sciences, MIT, Cambridge, MA 02139
| | - Rodrigo A. Cunha
- CNC – Center for Neuroscience and Cell Biology, University of Coimbra, Portugal
- Faculty of Medicine, University of Coimbra, Portugal
| | - Jia Qu
- School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical College Wenzhou, Zhejiang, China
| | - Jiang-Fan Chen
- Department of Neurology and Pharmacology, Boston University School of Medicine, Boston, MA 02118
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42
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Pak K, Zsuga J, Kepes Z, Erdei T, Varga B, Juhasz B, Szentmiklosi AJ, Gesztelyi R. The effect of adenosine deaminase inhibition on the A1 adenosinergic and M2 muscarinergic control of contractility in eu- and hyperthyroid guinea pig atria. Naunyn Schmiedebergs Arch Pharmacol 2015; 388:853-68. [PMID: 25877465 PMCID: PMC4495724 DOI: 10.1007/s00210-015-1121-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Accepted: 03/30/2015] [Indexed: 11/26/2022]
Abstract
The A1 adenosine and M2 muscarinic receptors exert protective (including energy consumption limiting) effects in the heart. We investigated the influence of adenosine deaminase (ADA) inhibition on a representative energy consumption limiting function, the direct negative inotropic effect elicited by the A1 adenosinergic and M2 muscarinergic systems, in eu- and hyperthyroid atria. Furthermore, we compared the change in the interstitial adenosine level caused by ADA inhibition and nucleoside transport blockade, two well-established processes to stimulate the cell surface A1 adenosine receptors, in both thyroid states. A classical isolated organ technique was applied supplemented with the receptorial responsiveness method (RRM), a concentration estimating procedure. Via measuring the contractile force, the direct negative inotropic capacity of N(6)-cyclopentyladenosine, a selective A1 receptor agonist, and methacholine, a muscarinic receptor agonist, was determined on the left atria isolated from 8-day solvent- and thyroxine-treated guinea pigs in the presence and absence of 2'-deoxycoformycin, a selective ADA inhibitor, and NBTI, a selective nucleoside transporter inhibitor. We found that ADA inhibition (but not nucleoside transport blockade) increased the signal amplification of the A1 adenosinergic (but not M2 muscarinergic) system. This action of ADA inhibition developed in both thyroid states, but it was greater in hyperthyroidism. Nevertheless, ADA inhibition produced a smaller rise in the interstitial adenosine concentration than nucleoside transport blockade did in both thyroid states. Our results indicate that ADA inhibition, besides increasing the interstitial adenosine level, intensifies the atrial A1 adenosinergic function in another (thyroid hormone-sensitive) way, suggesting a new mechanism of action of ADA inhibition.
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Affiliation(s)
- Krisztian Pak
- />Department of Pharmacology, Faculty of Pharmacy, University of Debrecen, Nagyerdei krt. 98, 4032 Debrecen, Hungary
| | - Judit Zsuga
- />Department of Health Systems Management and Quality Management for Health Care, Faculty of Public Health, University of Debrecen, Nagyerdei krt. 98, 4032 Debrecen, Hungary
| | - Zita Kepes
- />Department of Pharmacology, Faculty of Pharmacy, University of Debrecen, Nagyerdei krt. 98, 4032 Debrecen, Hungary
| | - Tamas Erdei
- />Department of Pharmacology, Faculty of Pharmacy, University of Debrecen, Nagyerdei krt. 98, 4032 Debrecen, Hungary
| | - Balazs Varga
- />Department of Pharmacology, Faculty of Pharmacy, University of Debrecen, Nagyerdei krt. 98, 4032 Debrecen, Hungary
| | - Bela Juhasz
- />Department of Pharmacology, Faculty of Pharmacy, University of Debrecen, Nagyerdei krt. 98, 4032 Debrecen, Hungary
| | - Andras Jozsef Szentmiklosi
- />Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Debrecen, Nagyerdei krt. 98, 4032 Debrecen, Hungary
| | - Rudolf Gesztelyi
- />Department of Pharmacology, Faculty of Pharmacy, University of Debrecen, Nagyerdei krt. 98, 4032 Debrecen, Hungary
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43
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Gazerani P, Cairns BE. Adenosine A3 receptor agonists: do recent findings offer new hope in chronic pain treatment? Pain Manag 2015; 5:75-80. [PMID: 25806901 DOI: 10.2217/pmt.15.4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Affiliation(s)
- Parisa Gazerani
- Center for Sensory-Motor Interaction (SMI), Department of Health Science & Technology, Faculty of Medicine, Aalborg University, Fredrik Bajers Vej 7D3, DK-9220 Aalborg East, Denmark
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44
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Godinho RO, Duarte T, Pacini ESA. New perspectives in signaling mediated by receptors coupled to stimulatory G protein: the emerging significance of cAMP efflux and extracellular cAMP-adenosine pathway. Front Pharmacol 2015; 6:58. [PMID: 25859216 PMCID: PMC4373373 DOI: 10.3389/fphar.2015.00058] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Accepted: 03/06/2015] [Indexed: 12/25/2022] Open
Abstract
G protein-coupled receptors (GPCRs) linked to stimulatory G (Gs) proteins (GsPCRs) mediate increases in intracellular cyclic AMP as consequence of activation of nine adenylyl cyclases , which differ considerably in their cellular distribution and activation mechanisms. Once produced, cyclic AMP may act via distinct intracellular signaling effectors such as protein kinase A and the exchange proteins activated by cAMP (Epacs). More recently, attention has been focused on the efflux of cAMP through a specific transport system named multidrug resistance proteins that belongs to the ATP-binding cassette transporter superfamily. Outside the cell, cAMP is metabolized into adenosine, which is able to activate four distinct subtypes of adenosine receptors, members of the GPCR family: A1, A2A, A2B, and A3. Taking into account that this phenomenon occurs in numerous cell types, as consequence of GsPCR activation and increment in intracellular cAMP levels, in this review, we will discuss the impact of cAMP efflux and the extracellular cAMP-adenosine pathway on the regulation of GsPCR-induced cell response.
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Affiliation(s)
- Rosely O Godinho
- Disciplina Farmacologia Celular, Departamento de Farmacologia, Escola Paulista de Medicina, Universidade Federal de São Paulo São Paulo, Brazil
| | - Thiago Duarte
- Disciplina Farmacologia Celular, Departamento de Farmacologia, Escola Paulista de Medicina, Universidade Federal de São Paulo São Paulo, Brazil
| | - Enio S A Pacini
- Disciplina Farmacologia Celular, Departamento de Farmacologia, Escola Paulista de Medicina, Universidade Federal de São Paulo São Paulo, Brazil
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45
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Sobrevia L, Salsoso R, Sáez T, Sanhueza C, Pardo F, Leiva A. Insulin therapy and fetoplacental vascular function in gestational diabetes mellitus. Exp Physiol 2015; 100:231-8. [PMID: 25581778 DOI: 10.1113/expphysiol.2014.082743] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Accepted: 01/06/2015] [Indexed: 01/08/2023]
Abstract
NEW FINDINGS What is the topic of this review? This review focuses on the effects of insulin therapy on fetoplacental vasculature in gestational diabetes mellitus and the potentiating effects of adenosine on this therapy. What advances does it highlight? This review highlights recent studies exploring a potential functional link between insulin receptors and their dependence on adenosine receptor activation (insulin-adenosine axis) to restore placental endothelial function in gestational diabetes mellitus. Gestational diabetes mellitus (GDM) is a disease that occurs during pregnancy and is associated with maternal and fetal hyperglycaemia. Women with GDM are treated via diet to control their glycaemia; however, a proportion of these patients do not achieve the recommended values of glycaemia and are subjected to insulin therapy until delivery. Even if a diet-treated GDM pregnancy leads to normal maternal and newborn glucose levels, fetoplacental vascular dysfunction remains evident. Thus, control of glycaemia via diet does not prevent GDM-associated fetoplacental vascular and metabolic alterations. We review the available information regarding insulin therapy in the context of its potential consequences for fetoplacental vascular function in GDM. We propose the possibility that insulin therapy to produce normoglycaemia in the mother and newborn may require additional therapeutic measures to restore the normal metabolic condition of the vascular network in GDM. A role for A1 and A2A adenosine receptors and insulin receptors A and B as well as a potential functional link in the cell signalling associated with the activation of these receptors is proposed. This possibility could be helpful for the planning of strategies, including adenosine receptor-improved insulin therapy, for the treatment of GDM patients, thereby promoting the wellbeing of the growing fetus, newborn and mother.
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Affiliation(s)
- Luis Sobrevia
- Cellular and Molecular Physiology Laboratory (CMPL), Division of Obstetrics and Gynaecology, School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile; University of Queensland Centre for Clinical Research (UQCCR), Faculty of Medicine and Biomedical Sciences, University of Queensland, Herston, Queensland, Australia; Department of Physiology, Faculty of Pharmacy, Universidad de Sevilla, Seville, Spain
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46
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Naranjo AN, Chevalier A, Cousins GD, Ayettey E, McCusker EC, Wenk C, Robinson AS. Conserved disulfide bond is not essential for the adenosine A2A receptor: Extracellular cysteines influence receptor distribution within the cell and ligand-binding recognition. BIOCHIMICA ET BIOPHYSICA ACTA 2015; 1848:603-14. [PMID: 25445670 PMCID: PMC4565196 DOI: 10.1016/j.bbamem.2014.11.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2014] [Revised: 10/22/2014] [Accepted: 11/10/2014] [Indexed: 11/16/2022]
Abstract
G protein-coupled receptors (GPCRs) are integral membrane proteins involved in cellular signaling and constitute major drug targets. Despite their importance, the relationship between structure and function of these receptors is not well understood. In this study, the role of extracellular disulfide bonds on the trafficking and ligand-binding activity of the human A2A adenosine receptor was examined. To this end, cysteine-to-alanine mutations were conducted to replace individual and both cysteines in three disulfide bonds present in the first two extracellular loops. Although none of the disulfide bonds were essential for the formation of plasma membrane-localized active GPCR, loss of the disulfide bonds led to changes in the distribution of the receptor within the cell and changes in the ligand-binding affinity. These results indicate that in contrast to many class A GPCRs, the extracellular disulfide bonds of the A2A receptor are not essential, but can modulate the ligand-binding activity, by either changing the conformation of the extracellular loops or perturbing the interactions of the transmembrane domains.
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Affiliation(s)
- Andrea N Naranjo
- Department of Chemical and Biomolecular Engineering, University of Delaware, 150 Academy Street, Newark, DE 19716, USA.
| | - Amy Chevalier
- Department of Chemical and Biomolecular Engineering, University of Delaware, 150 Academy Street, Newark, DE 19716, USA.
| | - Gregory D Cousins
- Department of Computer Science, Tulane University, 6823 St. Charles Ave, New Orleans, LA 70118, USA
| | - Esther Ayettey
- Department of Chemical and Biomolecular Engineering, University of Delaware, 150 Academy Street, Newark, DE 19716, USA
| | - Emily C McCusker
- Department of Chemical and Biomolecular Engineering, University of Delaware, 150 Academy Street, Newark, DE 19716, USA.
| | - Carola Wenk
- Department of Computer Science, Tulane University, 6823 St. Charles Ave, New Orleans, LA 70118, USA.
| | - Anne S Robinson
- Department of Chemical and Biomolecular Engineering, Tulane University, 300 Lindy Boggs Laboratory, 6823 St. Charles Ave, New Orleans, LA 70118, USA; Department of Chemical and Biomolecular Engineering, University of Delaware, 150 Academy Street, Newark, DE 19716, USA.
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47
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Ross AE, Venton BJ. Adenosine transiently modulates stimulated dopamine release in the caudate-putamen via A1 receptors. J Neurochem 2014; 132:51-60. [PMID: 25219576 DOI: 10.1111/jnc.12946] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Revised: 08/26/2014] [Accepted: 09/10/2014] [Indexed: 01/20/2023]
Abstract
Adenosine modulates dopamine in the brain via A1 and A2A receptors, but that modulation has only been characterized on a slow time scale. Recent studies have characterized a rapid signaling mode of adenosine that suggests a possible rapid modulatory role. Here, fast-scan cyclic voltammetry was used to characterize the extent to which transient adenosine changes modulate stimulated dopamine release (5 pulses at 60 Hz) in rat caudate-putamen brain slices. Exogenous adenosine was applied and dopamine concentration monitored. Adenosine only modulated dopamine when it was applied 2 or 5 s before stimulation. Longer time intervals and bath application of 5 μM adenosine did not decrease dopamine release. Mechanical stimulation of endogenous adenosine 2 s before dopamine stimulation also decreased stimulated dopamine release by 41 ± 7%, similar to the 54 ± 6% decrease in dopamine after exogenous adenosine application. Dopamine inhibition by transient adenosine was recovered within 10 min. The A1 receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine blocked the dopamine modulation, whereas dopamine modulation was unaffected by the A2A receptor antagonist SCH 442416. Thus, transient adenosine changes can transiently modulate phasic dopamine release via A1 receptors. These data demonstrate that adenosine has a rapid, but transient, modulatory role in the brain. Here, transient adenosine was shown to modulate phasic dopamine release on the order of seconds by acting at the A1 receptor. However, sustained increases in adenosine did not regulate phasic dopamine release. This study demonstrates for the first time a transient, neuromodulatory function of rapid adenosine to regulate rapid neurotransmitter release.
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Affiliation(s)
- Ashley E Ross
- Department of Chemistry, University of Virginia, Charlottesville, Virginia, USA
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48
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Guzmán-Gutiérrez E, Arroyo P, Salsoso R, Fuenzalida B, Sáez T, Leiva A, Pardo F, Sobrevia L. Role of Insulin and Adenosine in the Human Placenta Microvascular and Macrovascular Endothelial Cell Dysfunction in Gestational Diabetes Mellitus. Microcirculation 2014; 21:26-37. [DOI: 10.1111/micc.12077] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Accepted: 07/18/2013] [Indexed: 12/19/2022]
Affiliation(s)
- Enrique Guzmán-Gutiérrez
- Cellular and Molecular Physiology Laboratory (CMPL); Division of Obstetrics and Gynaecology; Medical Research Centre (CIM); School of Medicine; Faculty of Medicine; Pontificia Universidad Católica de Chile; Santiago Chile
| | - Pablo Arroyo
- Cellular and Molecular Physiology Laboratory (CMPL); Division of Obstetrics and Gynaecology; Medical Research Centre (CIM); School of Medicine; Faculty of Medicine; Pontificia Universidad Católica de Chile; Santiago Chile
| | - Rocío Salsoso
- Cellular and Molecular Physiology Laboratory (CMPL); Division of Obstetrics and Gynaecology; Medical Research Centre (CIM); School of Medicine; Faculty of Medicine; Pontificia Universidad Católica de Chile; Santiago Chile
| | - Bárbara Fuenzalida
- Cellular and Molecular Physiology Laboratory (CMPL); Division of Obstetrics and Gynaecology; Medical Research Centre (CIM); School of Medicine; Faculty of Medicine; Pontificia Universidad Católica de Chile; Santiago Chile
- Biomedical Department; Faculty of Health Sciences; Universidad de Antofagasta; Antofagasta Chile
| | - Tamara Sáez
- Cellular and Molecular Physiology Laboratory (CMPL); Division of Obstetrics and Gynaecology; Medical Research Centre (CIM); School of Medicine; Faculty of Medicine; Pontificia Universidad Católica de Chile; Santiago Chile
| | - Andrea Leiva
- Cellular and Molecular Physiology Laboratory (CMPL); Division of Obstetrics and Gynaecology; Medical Research Centre (CIM); School of Medicine; Faculty of Medicine; Pontificia Universidad Católica de Chile; Santiago Chile
| | - Fabián Pardo
- Cellular and Molecular Physiology Laboratory (CMPL); Division of Obstetrics and Gynaecology; Medical Research Centre (CIM); School of Medicine; Faculty of Medicine; Pontificia Universidad Católica de Chile; Santiago Chile
| | - Luis Sobrevia
- Cellular and Molecular Physiology Laboratory (CMPL); Division of Obstetrics and Gynaecology; Medical Research Centre (CIM); School of Medicine; Faculty of Medicine; Pontificia Universidad Católica de Chile; Santiago Chile
- University of Queensland Centre for Clinical Research; Herston Queensland Australia
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49
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Abstract
Platelet function tests have been traditionally used to aid in the diagnosis and management of patients with bleeding problems. Given the role of platelets in atherothrombosis, several dedicated platelet function instruments are now available that are simple to use and can be used as point-of-care assays. These can provide rapid assessment of platelet function within whole blood without the requirement of sample processing. Some tests can be used to monitor antiplatelet therapy and assess risk of bleeding and thrombosis, although current guidelines advise against this. This article discusses the potential utility of tests/instruments that are available.
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Affiliation(s)
- Paul Harrison
- School of Immunity and Infection, University of Birmingham Medical School, Birmingham, UK.
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50
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Penniston JT, Padányi R, Pászty K, Varga K, Hegedus L, Enyedi A. Apart from its known function, the plasma membrane Ca²⁺ATPase can regulate Ca²⁺ signaling by controlling phosphatidylinositol 4,5-bisphosphate levels. J Cell Sci 2013; 127:72-84. [PMID: 24198396 DOI: 10.1242/jcs.132548] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Plasma membrane Ca(2+) ATPases (PMCAs, also known as ATP2B1-ATP2B4) are known targets of phosphatidylinositol 4,5-bisphosphate [PtdIns(4,5)P₂], but if and how they control the PtdIns(4,5)P₂ pool has not been considered. We demonstrate here that PMCAs protect PtdIns(4,5)P₂ in the plasma membrane from hydrolysis by phospholipase C (PLC). Comparison of active and inactive PMCAs indicates that the protection operates by two mechanisms; one requiring active PMCAs, the other not. It appears that the mechanism requiring activity is the removal of the Ca(2+) required for sustained PLC activity, whereas the mechanism not requiring activity is PtdIns(4,5)P₂ binding. We show that in PMCA overexpressing cells, PtdIns(4,5)P₂ binding can lead to less inositol 1,4,5-triphosphate (InsP₃) and diminished Ca(2+) release from intracellular Ca(2+) pools. Inspection of a homology model of PMCA suggests that PMCAs have a conserved cluster of basic residues forming a 'blue collar' at the interface between the membrane core and the cytoplasmic domains. By molecular dynamics simulation, we found that the blue collar forms four binding pockets for the phosphorylated inositol head group of PtdIns(4,5)P₂; these pockets bind PtdIns(4,5)P₂ strongly and frequently. Our studies suggest that by having the ability to bind PtdIns(4,5)P₂, PMCAs can control the accessibility of PtdIns(4,5)P₂ for PLC and other PtdIns(4,5)P₂-mediated processes.
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Affiliation(s)
- John T Penniston
- Institute of Molecular Pharmacology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, H-1025 Budapest, Hungary
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