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Wang Y, Zhao S, Wang S, Zhang J, Zhao Y, Ye C, Zhao Z, Li J, Shen H, Wu D. Electrochemistry detection of estrogenic effect: Regulation of de novo purine synthesis and catabolism by gibberellin and fulvestrant. Bioelectrochemistry 2024; 156:108634. [PMID: 38160510 DOI: 10.1016/j.bioelechem.2023.108634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 12/16/2023] [Accepted: 12/22/2023] [Indexed: 01/03/2024]
Abstract
The estrogenic effect of plant growth regulators has been received little attention, which leads to the lack of relevant toxicity data. In this study, the estrogenic effect induced by gibberellin with ERα-dependent manner was found by E-screen and western blot methods, and the electrochemical signals of MCF-7 cells regulated by gibberellin and fulvestrant were investigated. The results showed that the electrochemical signals of MCF-7 cells were increased by gibberellin, while reduced by fulvestrant significantly, and displayed an extremely sensitive response to the effects of estrogenic effect induced by ERα agonist and antagonist. Western blot results showed that the expressions of phosphoribosyl pyrophosphate amidotransferase and hypoxanthine nucleotide dehydrogenase in de novo purine synthesis and adenine deaminase in catabolism were more effective regulated by gibberellin and fulvestrant, resulting in significant changes of the levels of guanine, hypoxanthine and xanthine in cells, and then electrochemical signals. The results provide a theoretical basis for the establishment of new electrochemical detection method of the estrogenic effect of plant regulators.
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Affiliation(s)
- Yuhang Wang
- College of Pharmacy, Jiamusi University, Jiamusi, Heilongjiang 154007, PR China
| | - Shuo Zhao
- College of Pharmacy, Jiamusi University, Jiamusi, Heilongjiang 154007, PR China
| | - Shuhong Wang
- College of Pharmacy, Jiamusi University, Jiamusi, Heilongjiang 154007, PR China
| | - Jing Zhang
- College of Pharmacy, Jiamusi University, Jiamusi, Heilongjiang 154007, PR China
| | - Yanli Zhao
- College of Pharmacy, Jiamusi University, Jiamusi, Heilongjiang 154007, PR China; Heilongjiang Provincial Key Laboratory of New Drug Development and Pharmacotoxicological Evaluation, Jiamusi University, Jiamusi 154007, PR China
| | - Cai Ye
- College of Pharmacy, Jiamusi University, Jiamusi, Heilongjiang 154007, PR China; Heilongjiang Provincial Key Laboratory of New Drug Development and Pharmacotoxicological Evaluation, Jiamusi University, Jiamusi 154007, PR China
| | - Zhiyu Zhao
- College of Pharmacy, Jiamusi University, Jiamusi, Heilongjiang 154007, PR China
| | - Jinlian Li
- College of Pharmacy, Jiamusi University, Jiamusi, Heilongjiang 154007, PR China; Heilongjiang Provincial Key Laboratory of New Drug Development and Pharmacotoxicological Evaluation, Jiamusi University, Jiamusi 154007, PR China.
| | - Hongkuan Shen
- Jiamusi Inspection and Testing Center, Jiamusi, Heilongjiang 154007, PR China.
| | - Dongmei Wu
- College of Pharmacy, Jiamusi University, Jiamusi, Heilongjiang 154007, PR China; Heilongjiang Provincial Key Laboratory of New Drug Development and Pharmacotoxicological Evaluation, Jiamusi University, Jiamusi 154007, PR China.
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2
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Nguyen ATN, Tran QL, Baltos JA, McNeill SM, Nguyen DTN, May LT. Small molecule allosteric modulation of the adenosine A 1 receptor. Front Endocrinol (Lausanne) 2023; 14:1184360. [PMID: 37435481 PMCID: PMC10331460 DOI: 10.3389/fendo.2023.1184360] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2023] [Accepted: 05/23/2023] [Indexed: 07/13/2023] Open
Abstract
G protein-coupled receptors (GPCRs) represent the target for approximately a third of FDA-approved small molecule drugs. The adenosine A1 receptor (A1R), one of four adenosine GPCR subtypes, has important (patho)physiological roles in humans. A1R has well-established roles in the regulation of the cardiovascular and nervous systems, where it has been identified as a potential therapeutic target for a number of conditions, including cardiac ischemia-reperfusion injury, cognition, epilepsy, and neuropathic pain. A1R small molecule drugs, typically orthosteric ligands, have undergone clinical trials. To date, none have progressed into the clinic, predominantly due to dose-limiting unwanted effects. The development of A1R allosteric modulators that target a topographically distinct binding site represent a promising approach to overcome current limitations. Pharmacological parameters of allosteric ligands, including affinity, efficacy and cooperativity, can be optimized to regulate A1R activity with high subtype, spatial and temporal selectivity. This review aims to offer insights into the A1R as a potential therapeutic target and highlight recent advances in the structural understanding of A1R allosteric modulation.
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Affiliation(s)
- Anh T. N. Nguyen
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia
| | - Quan L. Tran
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia
| | - Jo-Anne Baltos
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia
| | - Samantha M. McNeill
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia
| | - Diep T. N. Nguyen
- Department of Information Technology, Faculty of Engineering and Technology, Vietnam National University, Hanoi, Vietnam
| | - Lauren T. May
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia
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3
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Alberto AVP, Ferreira NCDS, Bonavita AGC, Nihei OK, de Farias FP, Bisaggio RDC, de Albuquerque C, Savino W, Coutinho‐Silva R, Persechini PM, Alves LA. Physiologic roles of P2 receptors in leukocytes. J Leukoc Biol 2022; 112:983-1012. [PMID: 35837975 PMCID: PMC9796137 DOI: 10.1002/jlb.2ru0421-226rr] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Revised: 06/13/2022] [Indexed: 01/01/2023] Open
Abstract
Since their discovery in the 1970s, purinergic receptors have been shown to play key roles in a wide variety of biologic systems and cell types. In the immune system, purinergic receptors participate in innate immunity and in the modulation of the adaptive immune response. In particular, P2 receptors, which respond to extracellular nucleotides, are widely expressed on leukocytes, causing the release of cytokines and chemokines and the formation of inflammatory mediators, and inducing phagocytosis, degranulation, and cell death. The activity of these receptors is regulated by ectonucleotidases-expressed in these same cell types-which regulate the availability of nucleotides in the extracellular environment. In this article, we review the characteristics of the main purinergic receptor subtypes present in the immune system, focusing on the P2 family. In addition, we describe the physiologic roles of the P2 receptors already identified in leukocytes and how they can positively or negatively modulate the development of infectious diseases, inflammation, and pain.
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Affiliation(s)
- Anael Viana Pinto Alberto
- Laboratory of Cellular Communication, Oswaldo Cruz InstituteOswaldo Cruz FoundationRio de JaneiroRJBrazil
| | | | | | - Oscar Kenji Nihei
- Center of Education and LetterState University of the West of ParanáFoz do IguaçuPRBrazil
| | | | - Rodrigo da Cunha Bisaggio
- Laboratory of Cellular Communication, Oswaldo Cruz InstituteOswaldo Cruz FoundationRio de JaneiroRJBrazil,Federal Institute of Education, Science, and Technology of Rio de JaneiroRio de JaneiroRJBrazil
| | | | - Wilson Savino
- Laboratory on Thymus Research, Oswaldo Cruz InstituteOswaldo Cruz FoundationRio de JaneiroRJBrazil,Brazilian National Institute of Science and Technology on NeuroimmunomodulationRio de Janeiro Research Network on NeuroinflammationRio de JaneiroRJBrazil
| | - Robson Coutinho‐Silva
- Laboratory of Immunophysiology, Carlos Chagas Filho Biophysics InstituteFederal University of Rio de JaneiroRio de JaneiroRJBrazil
| | - Pedro Muanis Persechini
- Laboratory of Immunobiophysics, Carlos Chagas Filho Biophysics InstituteFederal University of Rio de JaneiroRio de JaneiroRJBrazil
| | - Luiz Anastacio Alves
- Laboratory of Cellular Communication, Oswaldo Cruz InstituteOswaldo Cruz FoundationRio de JaneiroRJBrazil
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4
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Zimmermann H. History of ectonucleotidases and their role in purinergic signaling. Biochem Pharmacol 2020; 187:114322. [PMID: 33161020 DOI: 10.1016/j.bcp.2020.114322] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 11/03/2020] [Accepted: 11/03/2020] [Indexed: 12/15/2022]
Abstract
Ectonucleotidases are key for purinergic signaling. They control the duration of activity of purinergic receptor agonists. At the same time, they produce hydrolysis products as additional ligands of purinergic receptors. Due to the considerable diversity of enzymes, purinergic receptor ligands and purinergic receptors, deciphering the impact of extracellular purinergic receptor control has become a challenge. The first group of enzymes described were the alkaline phosphatases - at the time not as nucleotide-metabolizing but as nonspecific phosphatases. Enzymes now referred to as nucleoside triphosphate diphosphohydrolases and ecto-5'-nucleotidase were the first and only nucleotide-specific ectonucleotidases identified. And they were the first group of enzymes related to purinergic signaling. Additional research brought to light a surprising number of ectoenzymes with broad substrate specificity, which can also hydrolyze nucleotides. This short overview traces the development of the field and briefly highlights important results and benefits for therapies of human diseases achieved within nearly a century of investigations.
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Affiliation(s)
- Herbert Zimmermann
- Goethe University, Institute of Cell Biology and Neuroscience, Max-von-Laue-Str. 13, 60438 Frankfurt am Main, Germany.
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Effendi WI, Nagano T, Kobayashi K, Nishimura Y. Focusing on Adenosine Receptors as a Potential Targeted Therapy in Human Diseases. Cells 2020; 9:E785. [PMID: 32213945 PMCID: PMC7140859 DOI: 10.3390/cells9030785] [Citation(s) in RCA: 83] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Revised: 03/21/2020] [Accepted: 03/23/2020] [Indexed: 02/07/2023] Open
Abstract
Adenosine is involved in a range of physiological and pathological effects through membrane-bound receptors linked to G proteins. There are four subtypes of adenosine receptors, described as A1AR, A2AAR, A2BAR, and A3AR, which are the center of cAMP signal pathway-based drug development. Several types of agonists, partial agonists or antagonists, and allosteric substances have been synthesized from these receptors as new therapeutic drug candidates. Research efforts surrounding A1AR and A2AAR are perhaps the most enticing because of their concentration and affinity; however, as a consequence of distressing conditions, both A2BAR and A3AR levels might accumulate. This review focuses on the biological features of each adenosine receptor as the basis of ligand production and describes clinical studies of adenosine receptor-associated pharmaceuticals in human diseases.
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Affiliation(s)
- Wiwin Is Effendi
- Division of Respiratory Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan; (W.I.E.); (K.K.); (Y.N.)
- Department of Pulmonology and Respiratory Medicine, Medical Faculty of Airlangga University, Surabaya 60131, Indonesia
| | - Tatsuya Nagano
- Division of Respiratory Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan; (W.I.E.); (K.K.); (Y.N.)
| | - Kazuyuki Kobayashi
- Division of Respiratory Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan; (W.I.E.); (K.K.); (Y.N.)
| | - Yoshihiro Nishimura
- Division of Respiratory Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan; (W.I.E.); (K.K.); (Y.N.)
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Mathematical model reveals role of nucleotide signaling in airway surface liquid homeostasis and its dysregulation in cystic fibrosis. Proc Natl Acad Sci U S A 2017; 114:E7272-E7281. [PMID: 28808008 DOI: 10.1073/pnas.1617383114] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Mucociliary clearance is composed of three components (i.e., mucin secretion, airway surface hydration, and ciliary-activity) which function coordinately to clear inhaled microbes and other foreign particles from airway surfaces. Airway surface hydration is maintained by water fluxes driven predominantly by active chloride and sodium ion transport. The ion channels that mediate electrogenic ion transport are regulated by extracellular purinergic signals that signal through G protein-coupled receptors. These purinoreceptors and the signaling pathways they activate have been identified as possible therapeutic targets for treating lung disease. A systems-level description of airway surface liquid (ASL) homeostasis could accelerate development of such therapies. Accordingly, we developed a mathematical model to describe the dynamic coupling of ion and water transport to extracellular purinergic signaling. We trained our model from steady-state and time-dependent experimental measurements made using normal and cystic fibrosis (CF) cultured human airway epithelium. To reproduce CF conditions, reduced chloride secretion, increased potassium secretion, and increased sodium absorption were required. The model accurately predicted ASL height under basal normal and CF conditions and the collapse of surface hydration due to the accelerated nucleotide metabolism associated with CF exacerbations. Finally, the model predicted a therapeutic strategy to deliver nucleotide receptor agonists to effectively rehydrate the ASL of CF airways.
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7
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Lee SC, Lee H, Oh KB, Hwang IS, Yang H, Park MR, Ock SA, Woo JS, Im GS, Hwang S. Production and Breeding of Transgenic Cloned Pigs Expressing Human CD73. Dev Reprod 2017; 21:157-165. [PMID: 28785737 PMCID: PMC5532308 DOI: 10.12717/dr.2017.21.2.157] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Revised: 05/04/2017] [Accepted: 05/08/2017] [Indexed: 11/17/2022]
Abstract
One of the reasons to causing blood coagulation in the tissue of xenografted
organs was known to incompatibility of the blood coagulation and
anti-coagulation regulatory system between TG pigs and primates. Thus,
overexpression of human CD73 (hCD73) in the pig endothelial cells is considered
as a method to reduce coagulopathy after pig-to-non-human-primate
xenotransplantation. This study was performed to produce and breed transgenic
pigs expressing hCD73 for the studies immune rejection responses and could
provide a successful application of xenotransplantation. The transgenic cells
were constructed an hCD73 expression vector under control porcine Icam2 promoter
(pIcam2-hCD73) and established donor cell lines expressing hCD73. The numbers of
transferred reconstructed embryos were 127 ± 18.9. The pregnancy and delivery
rate of surrogates were 8/18 (44%) and 3/18 (16%). The total number of delivered
cloned pigs were 10 (2 alive, 7 mummy, and 1 died after birth). Among them,
three live hCD73-pigs were successfully delivered by Caesarean section, but one
was dead after birth. The two hCD73 TG cloned pigs had normal reproductive
ability. They mated with wild type (WT) MGH (Massachusetts General Hospital)
female sows and produced totally 16 piglets. Among them, 5 piglets were
identified as hCD73 TG pigs. In conclusion, we successfully generated the hCD73
transgenic cloned pigs and produced their litters by natural mating. It can be
possible to use a mate for the production of multiple transgenic pigs such as
α-1,3-galactosyltransferase knock-out /hCD46 for xenotransplantation.
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Affiliation(s)
- Seung-Chan Lee
- Animal Biotechnology Division, National Institute of Animal Science, RDA, Wanju 55365, Republic of Korea
| | - Haesun Lee
- Animal Biotechnology Division, National Institute of Animal Science, RDA, Wanju 55365, Republic of Korea
| | - Keon Bong Oh
- Animal Biotechnology Division, National Institute of Animal Science, RDA, Wanju 55365, Republic of Korea
| | - In-Sul Hwang
- Animal Biotechnology Division, National Institute of Animal Science, RDA, Wanju 55365, Republic of Korea
| | - Hyeon Yang
- Animal Biotechnology Division, National Institute of Animal Science, RDA, Wanju 55365, Republic of Korea
| | - Mi-Ryung Park
- Animal Biotechnology Division, National Institute of Animal Science, RDA, Wanju 55365, Republic of Korea
| | - Sun-A Ock
- Animal Biotechnology Division, National Institute of Animal Science, RDA, Wanju 55365, Republic of Korea
| | - Jae-Seok Woo
- Animal Biotechnology Division, National Institute of Animal Science, RDA, Wanju 55365, Republic of Korea
| | - Gi-Sun Im
- Animal Biotechnology Division, National Institute of Animal Science, RDA, Wanju 55365, Republic of Korea
| | - Seongsoo Hwang
- Animal Biotechnology Division, National Institute of Animal Science, RDA, Wanju 55365, Republic of Korea
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8
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Pelikant-Małecka I, Sielicka A, Kaniewska E, Smoleński RT, Słomińska EM. Influence of 4-pyridone-3-carboxamide-1Β-D-ribonucleoside (4PYR) on activities of extracellular enzymes in endothelial human cells. NUCLEOSIDES NUCLEOTIDES & NUCLEIC ACIDS 2017; 35:732-736. [PMID: 27906624 DOI: 10.1080/15257770.2016.1174263] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Previous studies demonstrated that human endothelial cells were capable to phosphorylate 4-pyridone-3-carboxamide-1β-D-ribonucleoside (4PYR) to monophosphate (4PYMP) and formed another metabolite-an analog of NAD (4PYRAD). Elevated levels of 4PYMP and 4PYRAD had an adverse effect on energy balance-depressed adenosine triphosphate (ATP) and nicotinamide adenine dinucleotide (NAD) concentration in human endothelial cells. Ecto-enzymes such as ecto-nucleoside triphosphate diphosphohydrolase (eNTPD); ecto-5'-nucleotidase (e5'NT); and ecto-adenosine deaminase (eADA) are involved in controlling of inflammation and platelet aggregation. This study aimed to evaluate influence of 4PYR and its metabolites on activities of extracellular enzymes in human endothelial cells. Endothelial cells (endothelial cell line HMEC-1) were treated with 100 uM 4PYR for 0, 24, 48, or 72 hours. After incubation, intact HMEC-1 cells were incubated with suitable substrate. Simultaneously, in another path of experiments intracellular concentration of 4PYMP and 4PYRAD had been analyzed. Conversion of extracellular nucleotides into their products and intracellular concentration of 4PYMP and 4PYRAD were measured by high performance liquid chromatography (HPLC). We demonstrated that eNTPD and e5'NT activities increase after 72 hours of cell treatment with 4PYR as compared to control (0.40 ± 0.02 versus 0.29 ± 0.02 nmol/min/mg protein; 13.3 ± 0.6 versus 8.30 ± 0.34 nmol/min/mg protein, respectively, mean ± SEM). eADA activity decreases after 24 hours of cells treatment with 4PYR as compared to control (1.55 ± 0.06 versus 1.92 ± 0.13 nmol/min/mg protein, respectively, mean ± SEM). 4PYR and its derivatives have positive effect on ecto-enzymes related with ATP degradation pathway. We conclude that these increases in extracellular enzyme activities are an adaptive response to decreased intracellular ATP and NAD arising from 4PYR uptake. These changes may protect the cells from the inflammatory result of external ATP degradation.
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Affiliation(s)
- I Pelikant-Małecka
- a Department of Biochemistry , Medical University of Gdansk , Gdansk , Poland
| | - A Sielicka
- a Department of Biochemistry , Medical University of Gdansk , Gdansk , Poland.,b Structural Heart Research Lab, Division of Cardiothoracic Surgery, Emory University , Atlanta , Georgia , USA
| | - E Kaniewska
- a Department of Biochemistry , Medical University of Gdansk , Gdansk , Poland
| | - R T Smoleński
- a Department of Biochemistry , Medical University of Gdansk , Gdansk , Poland
| | - E M Słomińska
- a Department of Biochemistry , Medical University of Gdansk , Gdansk , Poland
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9
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Boddum K, Jensen TP, Magloire V, Kristiansen U, Rusakov DA, Pavlov I, Walker MC. Astrocytic GABA transporter activity modulates excitatory neurotransmission. Nat Commun 2016; 7:13572. [PMID: 27886179 PMCID: PMC5133667 DOI: 10.1038/ncomms13572] [Citation(s) in RCA: 129] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Accepted: 10/14/2016] [Indexed: 12/12/2022] Open
Abstract
Astrocytes are ideally placed to detect and respond to network activity. They express ionotropic and metabotropic receptors, and can release gliotransmitters. Astrocytes also express transporters that regulate the extracellular concentration of neurotransmitters. Here we report a previously unrecognized role for the astrocytic GABA transporter, GAT-3. GAT-3 activity results in a rise in astrocytic Na+ concentrations and a consequent increase in astrocytic Ca2+ through Na+/Ca2+ exchange. This leads to the release of ATP/adenosine by astrocytes, which then diffusely inhibits neuronal glutamate release via activation of presynaptic adenosine receptors. Through this mechanism, increases in astrocytic GAT-3 activity due to GABA released from interneurons contribute to 'diffuse' heterosynaptic depression. This provides a mechanism for homeostatic regulation of excitatory transmission in the hippocampus.
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Affiliation(s)
- Kim Boddum
- Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK.,Faculty of Health and Medical Sciences, Department of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark
| | - Thomas P Jensen
- Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK
| | - Vincent Magloire
- Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK
| | - Uffe Kristiansen
- Faculty of Health and Medical Sciences, Department of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark
| | - Dmitri A Rusakov
- Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK
| | - Ivan Pavlov
- Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK
| | - Matthew C Walker
- Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK
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Lietsche J, Imran I, Klein J. Extracellular levels of ATP and acetylcholine during lithium-pilocarpine induced status epilepticus in rats. Neurosci Lett 2015; 611:69-73. [PMID: 26610905 DOI: 10.1016/j.neulet.2015.11.028] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Revised: 11/12/2015] [Accepted: 11/17/2015] [Indexed: 01/23/2023]
Abstract
Acetylcholine (ACh) and ATP are rapidly acting neurotransmitters with a putative role in epileptic seizures. In the present study we investigated extracellular concentrations of both neurotransmitters in parallel by microdialysis in rat hippocampus. We found that infusion of neostigmine increases, while calcium-free perfusion and infusion of tetrodotoxin (TTX) decreases, ACh levels. Calcium-free perfusion also decreased ATP levels which were, however, not affected by neostigmine or TTX. During status epilepticus, ACh levels were increased threefold but returned to baseline after the termination of seizures by diazepam. ATP levels were unchanged during status epilepticus but a several-fold increase was seen when AOPCP, an inhibitor of 5'-endonucleotidase, was infused. The results demonstrate an increase of ATP levels during epileptic seizures which, however, was not of neuronal origin.
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Affiliation(s)
- Jana Lietsche
- Department of Pharmacology, College of Pharmacy, Goethe University of Frankfurt, Germany
| | - Imran Imran
- Faculty of Pharmacy, Bahauddin Zakariya University, Multan, Pakistan
| | - Jochen Klein
- Department of Pharmacology, College of Pharmacy, Goethe University of Frankfurt, Germany.
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11
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De Giorgi M, Pelikant-Malecka I, Sielicka A, Slominska EM, Giovannoni R, Cinti A, Cerrito MG, Lavitrano M, Smolenski RT. Functional analysis of expression of human ecto-nucleoside triphosphate diphosphohydrolase-1 and/or ecto-5'-nucleotidase in pig endothelial cells. NUCLEOSIDES NUCLEOTIDES & NUCLEIC ACIDS 2015; 33:313-8. [PMID: 24940685 DOI: 10.1080/15257770.2014.896466] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Adenine nucleosides and nucleotides are important signaling molecules involved in control of key mechanisms of xenotransplant rejection. Extracellular pathway that converts ATP and ADP to AMP, and AMP to adenosine mainly mediated by ecto-nucleoside triphosphate diphosphohydrolase 1, (ENTPD1 or CD39) and ecto-5'-nucleotidase (E5NT or CD73) respectively, is considered as important target for xenograft protection. To clarify feasibility of combined expression of human ENTPD1 and E5NT and to study its functional effect we transfected pig endothelial cell line (PIEC) with both genes together. To do this we have produced a dicistronic construct bearing F2A sequence in frame between human E5NT and human ENTPD1 coding sequences. PIEC cells were mock-transfected as transfection control or transfected with plasmids encoding human ENTPD1 or human E5NT. PIEC cells were exposed to 50 μM ATP or 50 μM ADP or 50 μM AMP. Conversion of extracellular substrates into products (ATP/ADP/AMP/adenosine) was measured by HPLC in the media collected at specific time intervals. Following addition of AMP, production of adenosine in the medium of E5NT/ENTPD1- and E5NT- transfected cells increased to 14.2±1.1 and 24.5±3.4 μM respectively while it remained below 1 μM in controls and in ENTPD1-transfected cells. A marked increase of adenosine formation from ADP or ATP was observed only in E5NT/ENTPD1-transfected cells (11.7±0.1 and 5.7±2.2 μM respectively) but not in any other condition studied. This study indicates feasibility and functionality of combined expression of human E5NT and ENTPD1 in pig endothelial cells using F2A sequence bearing construct.
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Affiliation(s)
- M De Giorgi
- a Department of Surgery and Translational Medicine , University of Milano-Bicocca , Milano , Italy
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12
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Gifford JR, Heal C, Bridges J, Goldthorpe S, Mack GW. Changes in dermal interstitial ATP levels during local heating of human skin. J Physiol 2012; 590:6403-11. [PMID: 23045344 DOI: 10.1113/jphysiol.2012.240523] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Heating skin is believed to activate vanilloid type III and IV transient receptor potential ion channels (TRPV3, TRPV4, respectively), resulting in the release of ATP into the interstitial fluid. We examined the hypothesis that local skin heating would result in an accumulation of ATP in the interstitial fluid that would be related with a rise in skin blood flow (SkBF) and temperature sensation. Two microdialysis probes were inserted into the dermis on the dorsal aspect of the forearm in 15 young, healthy subjects. The probed skin was maintained at 31°C, 35°C, 39°C and 43°C for 8 min periods, during which SkBF was monitored as cutaneous vascular conductance (CVC). Dialysate was collected and analysed for ATP ([ATP](d)) using a luciferase-based assay, and ratings of perceived warmth were taken at each temperature. At a skin temperature of 31°C, [ATP](d) averaged 18.93 ± 4.06 nm and CVC averaged 12.57 ± 1.59% peak. Heating skin to 35°C resulted in an increase in CVC (17.63 ± 1.27% peak; P < 0.05), but no change in [ATP](d). Heating skin to 39°C and 43°C resulted in a decreased [ATP](d) (5.88 ± 1.68 nm and 8.75 ± 3.44 nm, respectively; P < 0.05), which was accompanied by significant elevations in CVC (38.90 ± 1.37% peak and 60.32 ± 1.95% peak, respectively; P < 0.05). Ratings of perceived warmth increased in proportion to the increase in skin temperature (r(2) = 0.75, P < 0.05). In conclusion, our data indicate that an accumulation of interstitial ATP does not occur during local heating, and therefore does not have a role in temperature sensation or the dilator response in human skin. Nevertheless, the low threshold of dilatation (35°C) indicates a possible role for the TRPV3, TRPV4 channels or the sensitization of other ion channels in mediating the dilator response.
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Affiliation(s)
- Jayson R Gifford
- Department of Exercise Sciences, Brigham Young University, Provo, UT, USA.
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Zimmermann H, Zebisch M, Sträter N. Cellular function and molecular structure of ecto-nucleotidases. Purinergic Signal 2012; 8:437-502. [PMID: 22555564 PMCID: PMC3360096 DOI: 10.1007/s11302-012-9309-4] [Citation(s) in RCA: 768] [Impact Index Per Article: 64.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2011] [Accepted: 02/01/2012] [Indexed: 12/12/2022] Open
Abstract
Ecto-nucleotidases play a pivotal role in purinergic signal transmission. They hydrolyze extracellular nucleotides and thus can control their availability at purinergic P2 receptors. They generate extracellular nucleosides for cellular reuptake and salvage via nucleoside transporters of the plasma membrane. The extracellular adenosine formed acts as an agonist of purinergic P1 receptors. They also can produce and hydrolyze extracellular inorganic pyrophosphate that is of major relevance in the control of bone mineralization. This review discusses and compares four major groups of ecto-nucleotidases: the ecto-nucleoside triphosphate diphosphohydrolases, ecto-5'-nucleotidase, ecto-nucleotide pyrophosphatase/phosphodiesterases, and alkaline phosphatases. Only recently and based on crystal structures, detailed information regarding the spatial structures and catalytic mechanisms has become available for members of these four ecto-nucleotidase families. This permits detailed predictions of their catalytic mechanisms and a comparison between the individual enzyme groups. The review focuses on the principal biochemical, cell biological, catalytic, and structural properties of the enzymes and provides brief reference to tissue distribution, and physiological and pathophysiological functions.
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Affiliation(s)
- Herbert Zimmermann
- Institute of Cell Biology and Neuroscience, Molecular and Cellular Neurobiology, Biologicum, Goethe-University Frankfurt, Max-von-Laue-Str. 13, 60438, Frankfurt am Main, Germany.
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Czarnecka J, Roszek K, Jabłoński A, Smoliński DJ, Komoszyński M. Some aspects of purinergic signaling in the ventricular system of porcine brain. Acta Vet Scand 2011; 53:54. [PMID: 21995888 PMCID: PMC3213016 DOI: 10.1186/1751-0147-53-54] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2011] [Accepted: 10/13/2011] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND Numerous signaling pathways function in the brain ventricular system, including the most important - GABAergic, glutaminergic and dopaminergic signaling. Purinergic signalization system - comprising nucleotide receptors, nucleotidases, ATP and adenosine and their degradation products - are also present in the brain. However, the precise role of nucleotide signalling pathway in the ventricular system has been not elucidated so far. The aim of our research was the identification of all three elements of purinergic signaling pathway in the porcine brain ventricular system. RESULTS Besides nucleotide receptors on the ependymocytes surface, we studied purines and pyrimidines in the CSF, including mechanisms of nucleotide signaling in the swine model (Sus scrofa domestica). The results indicate presence of G proteins coupled P2Y receptors on ependymocytes and also P2X receptors engaged in fast signal transmission. Additionally we found in CSF nucleotides and adenosine in the concentration sufficient to P receptors activation. These extracellular nucleotides are metabolised by adenylate kinase and nucleotidases from at least two families: NTPDases and NPPases. A low activity of these nucleotide metabolising enzymes maintains nucleotides concentration in ventricular system in micromolar range. ATP is degraded into adenosine and inosine. CONCLUSIONS Our results confirm the thesis about cross-talking between brain and ventricular system functioning in physiological as well as pathological conditions. The close interaction of brain and ventricular system may elicit changes in qualitative and quantitative composition of purines and pyrimidines in CSF. These changes can be dependent on the physiological state of brain, including pathological processes in CNS.
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Ferenz KB, Rose K, König S, Krieglstein J. ATP-NGF-complex, but not NGF, is the neuroprotective ligand. Neurochem Int 2011; 59:989-95. [PMID: 21930174 DOI: 10.1016/j.neuint.2011.08.020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2011] [Revised: 08/25/2011] [Accepted: 08/26/2011] [Indexed: 12/12/2022]
Abstract
We have shown previously that nerve growth factor (NGF) requires only low nanomolar ATP concentrations in the cell culture medium to protect cortical rat neurons (CRN) from cellular damage induced by staurosporine (STS). We have also demonstrated before that NGF and other growth factors form stable non-covalent complexes with ATP. Here we demonstrated that 8N(1)ATP-NGF, but not NGF, protected CRN against damage. The photo-reactive ATP derivative 8N(3)ATP was incubated with NGF and was trapped in its position by UV irradiation forming a covalent bond. The cross-link with a molar ratio of 1:1 (8N(1)ATP:NGF) was confirmed by mass spectrometry. Circular dichroism experiments revealed that 8N(1)ATP altered the secondary structure of NGF in the same way as ATP did. Covalently bound 8N(1)ATP-NGF was shown to be stable in the presence of the ATP-hydrolyzing enzyme alkaline phosphatase while the non-covalent ATP-NGF-complex dissociated with the removal of free ATP from the solution. 8N(1)ATP-NGF protected CRN against damage by STS independently of free ATP in the culture medium. These results suggest that the ATP-NGF-complex, but not NGF, is the active ligand.
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Affiliation(s)
- Katja Bettina Ferenz
- Institut für Pharmazeutische und Medizinische Chemie, Fachbereich Chemie und Pharmazie, Germany
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Knowles AF. The GDA1_CD39 superfamily: NTPDases with diverse functions. Purinergic Signal 2011; 7:21-45. [PMID: 21484095 DOI: 10.1007/s11302-010-9214-7] [Citation(s) in RCA: 117] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2010] [Accepted: 12/21/2010] [Indexed: 01/05/2023] Open
Abstract
The first comprehensive review of the ubiquitous "ecto-ATPases" by Plesner was published in 1995. A year later, a lymphoid cell activation antigen, CD39, that had been cloned previously, was shown to be an ecto-ATPase. A family of proteins, related to CD39 and a yeast GDPase, all containing the canonical apyrase conserved regions in their polypeptides, soon started to expand. They are now recognized as members of the GDA1_CD39 protein family. Because proteins in this family hydrolyze nucleoside triphosphates and diphosphates, a unifying nomenclature, nucleoside triphosphate diphopshohydrolases (NTPDases), was established in 2000. Membrane-bound NTPDases are either located on the cell surface or membranes of intracellular organelles. Soluble NTPDases exist in the cytosol and may be secreted. In the last 15 years, molecular cloning and functional expression have facilitated biochemical characterization of NTPDases of many organisms, culminating in the recent structural determination of the ecto-domain of a mammalian cell surface NTPDase and a bacterial NTPDase. The first goal of this review is to summarize the biochemical, mutagenesis, and structural studies of the NTPDases. Because of their ability in hydrolyzing extracellular nucleotides, the mammalian cell surface NTPDases (the ecto-NTPDases) which regulate purinergic signaling have received the most attention. Less appreciated are the functions of intracellular NTPDases and NTPDases of other organisms, e.g., bacteria, parasites, Drosophila, plants, etc. The second goal of this review is to summarize recent findings which demonstrate the involvement of the NTPDases in multiple and diverse physiological processes: pathogen-host interaction, plant growth, eukaryote cell protein and lipid glycosylation, eye development, and oncogenesis.
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Affiliation(s)
- Aileen F Knowles
- Department of Chemistry and Biochemistry, San Diego State University, 5500 Campanile Drive, San Diego, CA, 92182-1030, USA,
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Meilanov IS, Klichkhanov NK, Djafarova AM, Tikra MH. Thermal denaturation of acetylcholinesterase of brain synaptic membranes of ground squirrels in hibernation. NEUROCHEM J+ 2010. [DOI: 10.1134/s1819712410040021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Gunosewoyo H, Kassiou M. P2X purinergic receptor ligands: recently patented compounds. Expert Opin Ther Pat 2010; 20:625-46. [DOI: 10.1517/13543771003702424] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Kudryashov IE. Effects of some derivatives of purine nucleotides in the nervous tissue: Focus on adenosine and xanthine. NEUROCHEM J+ 2009. [DOI: 10.1134/s1819712409040011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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21
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Ichikawa J, Gemba H. Cell density-dependent changes in intracellular Ca2+ mobilization via the P2Y2 receptor in rat bone marrow stromal cells. J Cell Physiol 2009; 219:372-81. [PMID: 19140137 DOI: 10.1002/jcp.21680] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Bone marrow stromal cells (BMSCs) are an interesting subject of research because they have characteristics of mesenchymal stem cells. We investigated intracellular Ca(2+) signaling in rat BMSCs. Agonists for purinergic receptors increased intracellular Ca(2+) levels ([Ca(2+)](i)). The order of potency followed ATP = UTP > ADP = UDP. ATP-induced rise in [Ca(2+)](i) was suppressed by U73122 and suramin, but not by pyridoxalphosphate-6-azophenyl-2',4'-disulfonic acid (PPADS), suggesting the functional expression of G protein-coupled P2Y(2) receptors. RT-PCR and immunohistochemical studies also showed the expression of P2Y(2) receptors. [Ca(2+)](i) response to UTP changed with cell density. The UTP-induced rise in [Ca(2+)](i) was greatest at high density. V(max) (maximum Ca(2+) response) and EC(50) (agonist concentration that evokes 50% of V(max)) suggest that the amount and property of P2Y(2) receptors were changed by cell density. Note that UTP induced Ca(2+) oscillation at only medium cell density. Pharmacological studies indicated that UTP-induced Ca(2+) oscillation required Ca(2+) influx by store-operated Ca(2+) entry. Carbenoxolone, a gap junction blocker, enhanced Ca(2+) oscillation. Immunohistochemical and quantitative real-time PCR studies revealed that proliferating cell nuclear antigen (PCNA)-positive cells declined but the mRNA expression level of the P2Y(2) receptor increased as cell density increased. Co-application of fetal calf serum with UTP induced Ca(2+) oscillation at high cell density. These results suggest that the different patterns observed for [Ca(2+)](i) mobilization with respect to cell density may be associated with cell cycle progression.
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Affiliation(s)
- Jun Ichikawa
- Department of Physiology 2, Kansai Medical University, Osaka, Japan.
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22
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Adenine nucleotide effect on intraocular pressure: Involvement of the parasympathetic nervous system. Exp Eye Res 2009; 89:63-70. [PMID: 19250934 DOI: 10.1016/j.exer.2009.02.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2008] [Revised: 01/18/2009] [Accepted: 02/16/2009] [Indexed: 01/02/2023]
Abstract
Nucleotides are present in the aqueous humor possibly exerting physiological effects on intraocular pressure (IOP). To determine the effect of nucleotides such as ATP and its related derivatives on IOP, New Zealand white rabbits were used. IOP was measured in rabbits treated topically either with saline (control) or with a single dose (10 microg/microL) of adenine nucleotides (ATP, 2-meS-ATP, ATP-gamma-S, alpha,beta-meADP, alpha,beta-meATP and beta,gamma-meATP). Those nucleotides reducing IOP (alpha,beta-meATP and beta,gamma-meATP) were then tested in concentrations ranging from 1 to 100 microg/microL to obtain the IC(50) value. Several antagonists for the P2 and adenosine A1 receptors (all at 10 microg/microL) were assayed 30 min before the application of the hypotensive nucleotide beta,gamma-meATP. To see whether the nucleotide was acting directly on the structures involved in aqueous humor dynamics or on the autonomic nerves controlling IOP, animal denervation and sympathetic (yohimbine and ICI-118,551 at 10 microg/microL) and parasympathetic (atropine and hexametonium at 10 microg/microL) receptors' antagonists were used 30 min before the instillation of beta,gamma-meATP. alpha,beta-meATP and beta,gamma-meATP decreased IOP to 60% of control value (basal IOP=23.2+/-1.3 mmHg), with IC(50) of 1.59+/-0.21 microg/microLand 0.56+/-0.62 microg/microL, which corresponds to 3mM and 1mM respectively. Denervation completely abolished the effect of beta,gamma-meATP. Sympathetic antagonists did not modify the hypotensive effect of beta,gamma-meATP, but parasympathetic antagonists were able to abolish it. Among the series of adenine nucleotide tested, alpha,beta-meATP and beta,gamma-meATP presented hypotensive actions on IOP. beta,gamma-meATP seems to stimulate cholinergic terminals being its final effect the IOP reduction. Therefore, these two nucleotides are interesting pharmacological tools for those pathologies related with high intraocular pressure.
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Langer D, Hammer K, Koszalka P, Schrader J, Robson S, Zimmermann H. Distribution of ectonucleotidases in the rodent brain revisited. Cell Tissue Res 2008; 334:199-217. [PMID: 18843508 DOI: 10.1007/s00441-008-0681-x] [Citation(s) in RCA: 122] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2008] [Accepted: 08/19/2008] [Indexed: 12/20/2022]
Abstract
Nucleotides comprise a major class of signaling molecules in the nervous system. They can be released from nerve cells, glial cells, and vascular cells where they exert their function via ionotropic (P2X) or metabotropic (P2Y) receptors. Signaling via extracellular nucleotides and also adenosine is controlled and modulated by cell-surface-located enzymes (ectonucleotidases) that hydrolyze the nucleotide to the respective nucleoside. Extracellular hydrolysis of nucleotide ligands involves a considerable number of enzymes with differing catalytic properties differentially affecting the nucleotide signaling pathway. It is therefore important to investigate which type of ectonucleotidase(s) contributes to the control of nucleotide signaling in distinct cellular and physiological settings. By using a classical enzyme histochemical approach and employing various substrates, inhibitors, and knockout animals, we provide, for the first time, a comparative analysis of the overall distribution of catalytic activities reflecting four ectonucleotidase families: ecto-5'-nucleotidase, alkaline phosphatases, ectonucleoside triphosphate diphosphohydrolases (E-NTPDases), and ectonucleotide pyrophyphatases/phosphodiesterases (E-NPPs). We place into perspective the earlier literature and provide novel evidence for a parenchymal localization of tissue non-specific alkaline phosphatase, E-NPPs, and E-NTPDases in the mouse brain. In addition, we specify the location of ectonucleotidases within the brain vasculature. Most notably, brain vessels do not express ecto-5'-nucleotidase. The preponderance of individual enzymes differs considerably between brain locations. The contribution of all types of ectonucleotidases thus needs to be considered in physiological and pharmacological studies of purinergic signaling in the brain.
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Affiliation(s)
- David Langer
- Institute of Cell Biology and Neuroscience, Biocenter, Goethe University Frankfurt am Main, Max-von-Laue-Str. 9, 60438, Frankfurt, Germany
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Yegutkin GG. Nucleotide- and nucleoside-converting ectoenzymes: Important modulators of purinergic signalling cascade. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2008; 1783:673-94. [PMID: 18302942 DOI: 10.1016/j.bbamcr.2008.01.024] [Citation(s) in RCA: 851] [Impact Index Per Article: 53.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2007] [Revised: 01/15/2008] [Accepted: 01/22/2008] [Indexed: 12/19/2022]
Abstract
The involvement of extracellular nucleotides and adenosine in an array of cell-specific responses has long been known and appreciated, but the integrative view of purinergic signalling as a multistep coordinated cascade has emerged recently. Current models of nucleotide turnover include: (i) transient release of nanomolar concentrations of ATP and ADP; (ii) triggering of signalling events via a series of ligand-gated (P2X) and metabotropic (P2Y) receptors; (iii) nucleotide breakdown by membrane-bound and soluble nucleotidases, including the enzymes of ecto-nucleoside triphosphate diphosphohydrolase (E-NTPDase) family, ecto-nucleotide pyrophosphatase/phosphodiesterase (E-NPP) family, ecto-5'-nucleotidase/CD73, and alkaline phosphatases; (iv) interaction of the resulting adenosine with own nucleoside-selective receptors; and finally, (v) extracellular adenosine inactivation via adenosine deaminase and purine nucleoside phosphorylase reactions and/or nucleoside uptake by the cells. In contrast to traditional paradigms that focus on purine-inactivating mechanisms, it has now become clear that "classical" intracellular ATP-regenerating enzymes, adenylate kinase, nucleoside diphosphate (NDP) kinase and ATP synthase can also be co-expressed on the cell surface. Furthermore, data on the ability of various cells to retain micromolar ATP levels in their pericellular space, as well as to release other related compounds (adenosine, UTP, dinucleotide polyphosphates and nucleotide sugars) gain another important insight into our understanding of mechanisms regulating a signalling cascade. This review summarizes recent advances in this rapidly evolving field, with particular emphasis on the nucleotide-releasing and purine-converting pathways in the vasculature.
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Affiliation(s)
- Gennady G Yegutkin
- MediCity Research Laboratory, University of Turku and National Public Health Institute, Turku, Finland.
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25
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One-step Bioluminescence ATPase Assay for the Evaluation of Neurotoxic Effects of Metal Ions. MONATSHEFTE FUR CHEMIE 2007. [DOI: 10.1007/s00706-007-0595-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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26
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Osman L, Amrani M, Isley C, Yacoub MH, Smolenski RT. Stimulatory effects of atorvastatin on extracellular nucleotide degradation in human endothelial cells. NUCLEOSIDES NUCLEOTIDES & NUCLEIC ACIDS 2007; 25:1125-8. [PMID: 17065076 DOI: 10.1080/15257770600894196] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Endothelial degradation of extracellular nucleotides is known to be an important mechanism in regulation of thrombosis, inflammation and immune response. It is possible that this pathway is a target for pleiotropic drugs such as atorvastatin. We studied therefore the effect of atorvastatin on extracellular nucleotide degradation in human endothelial cells. Atorvastatin treatment of human umbilical vein endothelial cells (HUVEC) and human microvascular endothelial cells (HMEC-1) resulted in significant increase in ATP breakdown and adenosine formation both if analysed in intact cell studies and as enzyme activity in cell lysates. We conclude that one of the beneficial effects of atorvastatin may include acceleration of extracellular nucleotide breakdown. This will attenuate nucleotide mediated pro-inflammatory effect and stimulate protective mechanisms of adenosine.
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Affiliation(s)
- L Osman
- Heart Science Centre, Imperial College at Harefield Hospital, Harefield, UK
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Schetinger MRC, Morsch VM, Bonan CD, Wyse ATS. NTPDase and 5'-nucleotidase activities in physiological and disease conditions: new perspectives for human health. Biofactors 2007; 31:77-98. [PMID: 18806312 DOI: 10.1002/biof.5520310205] [Citation(s) in RCA: 160] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Extracellular nucleotides and nucleosides act as signaling molecules involved in a wide spectrum of biological effects. Their levels are controlled by a complex cell surface-located group of enzymes called ectonucleotidases. There are four major families of ectonucleotidases, nucleoside triphosphate diphosphohydrolases (NTPDases/CD39), ectonucleotide pyrophosphatase/phosphodiesterases (E-NPPs), alkaline phosphatases and ecto-5'-nucleotidase. In the last few years, substantial progress has been made toward the molecular identification of members of the ectonucleotidase families and their enzyme structures and functions. In this review, there is an emphasis on the involvement of NTPDase and 5'-nucleotidase activities in disease processes in several tissues and cell types. Brief background information is given about the general characteristics of these enzymes, followed by a discussion of their roles in thromboregulatory events in diabetes, hypertension, hypercholesterolemia and cancer, as well as in pathological conditions where platelets are less responsive, such as in chronic renal failure. In addition, immunomodulation and cell-cell interactions involving these enzymes are considered, as well as ATP and ADP hydrolysis under different clinical conditions related with alterations in the immune system, such as acute lymphoblastic leukemia (ALL), B-chronic lymphocytic leukemia (B-CLL) and infections associated with human immunodeficiency virus (HIV). Finally, changes in ATP, ADP and AMP hydrolysis induced by inborn errors of metabolism, seizures and epilepsy are discussed in order to highlight the importance of these enzymes in the control of neuronal activity in pathological conditions. Despite advances made toward understanding the molecular structure of ectonucleotidases, much more investigation will be necessary to entirely grasp their role in physiological and pathological conditions.
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Affiliation(s)
- Maria Rosa C Schetinger
- Laboratório de Enzimologia Toxicológica, Departamento de Química, CCNE, Universidade Federal de Santa Maria, Avenida Roraima, no 1000, Cidade Universitária, Bairro Camobi, Santa Maria-RS, 97105-900, Brazil.
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De Jesus JB, Ferreira MA, Cuervo P, Britto C, e Silva-Filho FC, Meyer-Fernandes JR. Iron modulates ecto-phosphohydrolase activities in pathogenic trichomonads. Parasitol Int 2006; 55:285-90. [PMID: 17010660 DOI: 10.1016/j.parint.2006.08.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2006] [Revised: 07/21/2006] [Accepted: 08/21/2006] [Indexed: 11/27/2022]
Abstract
The presence of iron in the extracellular medium is essential for both in vivo and in vitro survival of pathogenic microorganisms, including Trichomonas vaginalis and Tritrichomonas foetus. In these parasites, iron is directly involved in the proliferation, protein expression and activation of critical enzymes. The purpose of this study was to investigate the role of iron in ecto-ATPase, ecto-phophatase and secreted phosphatase activities of these trichomonads. We observed that trichomonads grown in iron-depleted medium exhibited a remarkable decrease in both ecto-ATPase and ecto-phosphatase activities, when compared to those cultivated under control conditions (iron-rich medium). Furthermore, parasites grown in iron-depleted medium restored their enzyme activities when they were re-inoculated into fresh iron-rich medium. We demonstrated that modulation of ecto-phosphohydrolase activities is due neither to enzyme-iron nor to substrate-iron complex formation, since iron addition directly to the medium where the enzymatic reactions occurred did not alter their activities. Previously, we had reported that a fresh clinical isolate of T. vaginalis was much more cytotoxic to epithelial cell monolayers than a long-term cultured one. In this study we witnessed that the fresh isolate of T. vaginalis presented higher activities to all herein investigated enzymes than the long-term cultured one. Altogether, our data clearly point out that iron has a pivotal role in the expression of phosphohydrolases in both trichomonads.
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Affiliation(s)
- José Batista De Jesus
- Departamento de Bioquímica e Biologia Molecular, Instituto Oswaldo Cruz, Pav Leônidas Deane, Brasil, 4365, Manguinhos, Rio de Janeiro, RJ, Brazil.
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Wozniacka A, Szajerski P, Adamus J, Gebicki J, Sysa-Jedrzejowska A. In search for new antipsoriatic agents: NAD topical composition. Skin Pharmacol Physiol 2006; 20:37-42. [PMID: 17035720 DOI: 10.1159/000096170] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2005] [Accepted: 04/21/2006] [Indexed: 11/19/2022]
Abstract
The aim of the study was to examine the effectiveness of the oxidized form of nicotinamide adenine dinucleotide (NAD(+)), adenosine precursor, in 37 patients suffering from psoriasis. As NAD(+) is known to be relatively unstable, the second goal was to establish the proper conditions for the satisfactory stability of topical NAD(+) composition. In each patient, two matching plaques were selected for the study. Topical treatment with 1 or 0.3% NAD(+) in Vaseline ointment administered twice daily was compared with overnight therapy with 0.1% anthralin applied for 12 h and placebo. The enzymatic method was applied to determine the stability of NAD(+) in Vaseline ointment. After a 4-week application, the reduction in erythema, infiltration and desquamation caused by 1 or 0.3% topical NAD(+) composition was similar to the reduction caused by 0.1% anthralin. It was demonstrated that NAD(+) underwent a considerable decomposition at room temperature, while it was sufficiently stable at 5 degrees C; thus, for a longer use the agent should be stored at fridge temperature. NAD(+) therapy combines good efficacy, cosmetic acceptability and convenient twice-daily application.
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Affiliation(s)
- A Wozniacka
- Department of Dermatology, Medical University, Lodz, Poland.
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Abbracchio MP, Burnstock G, Boeynaems JM, Barnard EA, Boyer JL, Kennedy C, Knight GE, Fumagalli M, Gachet C, Jacobson KA, Weisman GA. International Union of Pharmacology LVIII: update on the P2Y G protein-coupled nucleotide receptors: from molecular mechanisms and pathophysiology to therapy. Pharmacol Rev 2006; 58:281-341. [PMID: 16968944 PMCID: PMC3471216 DOI: 10.1124/pr.58.3.3] [Citation(s) in RCA: 987] [Impact Index Per Article: 54.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
There have been many advances in our knowledge about different aspects of P2Y receptor signaling since the last review published by our International Union of Pharmacology subcommittee. More receptor subtypes have been cloned and characterized and most orphan receptors de-orphanized, so that it is now possible to provide a basis for a future subdivision of P2Y receptor subtypes. More is known about the functional elements of the P2Y receptor molecules and the signaling pathways involved, including interactions with ion channels. There have been substantial developments in the design of selective agonists and antagonists to some of the P2Y receptor subtypes. There are new findings about the mechanisms underlying nucleotide release and ectoenzymatic nucleotide breakdown. Interactions between P2Y receptors and receptors to other signaling molecules have been explored as well as P2Y-mediated control of gene transcription. The distribution and roles of P2Y receptor subtypes in many different cell types are better understood and P2Y receptor-related compounds are being explored for therapeutic purposes. These and other advances are discussed in the present review.
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Affiliation(s)
- Maria P Abbracchio
- Department of Pharmacological Sciences, University of Milan, Milan, Italy
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Milosević M, Petrović S, Demajo M, Horvat A. Effects of metal ions on plasma membrane Mg2+-atpase in rat uterus and ovaries. Ann N Y Acad Sci 2006; 1048:445-8. [PMID: 16154973 DOI: 10.1196/annals.1342.061] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The in vitro effects of cadmium and mercury were investigated on the Mg(2+)-ATPase activity of plasma membranes from the rat ovary and uterus. ATP hydrolyzing activities were significant and dose-dependent-inhibited in both plasma membrane preparations by both metals. According to the IC(50) and apparent K(i), Cd(2+) was most potent in the ovary, while Hg(2+) was most potent in the uterus. In ovaries and uterus, Cd(2+) inhibits competitively, while Hg(2+) inhibits noncompetitively in both organs. The observed inhibition was a consequence of direct action of the chosen metal ions on the enzyme protein and by decreasing ATP hydrolysis, Hg(2+) and Cd(2+) may affect mammalian fertility.
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Affiliation(s)
- Maja Milosević
- Institute of Nuclear Sciences Vinca, Laboratory for Molecular Biology and Endocrinology, Belgrade, Serbia and Montenegro
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Marcet B, Boeynaems JM. Relationships between cystic fibrosis transmembrane conductance regulator, extracellular nucleotides and cystic fibrosis. Pharmacol Ther 2006; 112:719-32. [PMID: 16828872 DOI: 10.1016/j.pharmthera.2006.05.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2006] [Accepted: 05/26/2006] [Indexed: 10/24/2022]
Abstract
Cystic fibrosis (CF) is one of the most common lethal autosomal recessive genetic diseases in the Caucasian population, with a frequency of about 1 in 3000 livebirths. CF is due to a mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene encoding the CFTR protein, a cyclic adenosine 5'-monophosphate (cAMP)-regulated chloride channel localized in the apical membrane of epithelial cells. CFTR is a multifunctional protein which, in addition to be a Cl-channel, is also a regulator of multiple ion channels and other proteins. In particular CFTR has been reported to play a role in the outflow of adenosine 5'-triphosphate (ATP) from cells, but this remains controversial. Extracellular nucleotides are signaling molecules that regulate ion transport and mucociliary clearance by acting on P2 nucleotide receptors, in particular the P2Y(2) receptor. Nucleotides activating the P2Y(2) receptor represent thus one pharmacotherapeutic strategy to treat CF disease, via improvement of mucus hydration and mucociliary clearance in airways. Phase II clinical trials have recently shown that aerosolized denufosol (INS37217, Inspire(R)) improves pulmonary function in CF patients: denufosol was granted orphan drug status and phase III trials are planned. Here, we review what is known about the relationship between extracellular nucleotides and CFTR, the role of extracellular nucleotides in epithelial pathophysiology and their putative role as therapeutic agents.
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Affiliation(s)
- Brice Marcet
- Institute of Interdisciplinary Research, IRIBHM, Université Libre de Bruxelles, Campus Erasme (Bât C5-110), route de Lennik 808, 1070 Brussels, Belgium.
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Bours MJL, Swennen ELR, Di Virgilio F, Cronstein BN, Dagnelie PC. Adenosine 5'-triphosphate and adenosine as endogenous signaling molecules in immunity and inflammation. Pharmacol Ther 2006; 112:358-404. [PMID: 16784779 DOI: 10.1016/j.pharmthera.2005.04.013] [Citation(s) in RCA: 770] [Impact Index Per Article: 42.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2005] [Accepted: 04/20/2005] [Indexed: 02/07/2023]
Abstract
Human health is under constant threat of a wide variety of dangers, both self and nonself. The immune system is occupied with protecting the host against such dangers in order to preserve human health. For that purpose, the immune system is equipped with a diverse array of both cellular and non-cellular effectors that are in continuous communication with each other. The naturally occurring nucleotide adenosine 5'-triphosphate (ATP) and its metabolite adenosine (Ado) probably constitute an intrinsic part of this extensive immunological network through purinergic signaling by their cognate receptors, which are widely expressed throughout the body. This review provides a thorough overview of the effects of ATP and Ado on major immune cell types. The overwhelming evidence indicates that ATP and Ado are important endogenous signaling molecules in immunity and inflammation. Although the role of ATP and Ado during the course of inflammatory and immune responses in vivo appears to be extremely complex, we propose that their immunological role is both interdependent and multifaceted, meaning that the nature of their effects may shift from immunostimulatory to immunoregulatory or vice versa depending on extracellular concentrations as well as on expression patterns of purinergic receptors and ecto-enzymes. Purinergic signaling thus contributes to the fine-tuning of inflammatory and immune responses in such a way that the danger to the host is eliminated efficiently with minimal damage to healthy tissues.
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Affiliation(s)
- M J L Bours
- Maastricht University, Department of Epidemiology, Nutrition and Toxicology Research Institute Maastricht, P.O. Box 616, 6200 MD Maastricht, The Netherlands.
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Robson SC, Sévigny J, Zimmermann H. The E-NTPDase family of ectonucleotidases: Structure function relationships and pathophysiological significance. Purinergic Signal 2006; 2:409-30. [PMID: 18404480 PMCID: PMC2254478 DOI: 10.1007/s11302-006-9003-5] [Citation(s) in RCA: 712] [Impact Index Per Article: 39.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2005] [Accepted: 01/23/2006] [Indexed: 12/17/2022] Open
Abstract
Ectonucleotidases are ectoenzymes that hydrolyze extracellular nucleotides to the respective nucleosides. Within the past decade, ectonucleotidases belonging to several enzyme families have been discovered, cloned and characterized. In this article, we specifically address the cell surface-located members of the ecto-nucleoside triphosphate diphosphohydrolase (E-NTPDase/CD39) family (NTPDase1,2,3, and 8). The molecular identification of individual NTPDase subtypes, genetic engineering, mutational analyses, and the generation of subtype-specific antibodies have resulted in considerable insights into enzyme structure and function. These advances also allow definition of physiological and patho-physiological implications of NTPDases in a considerable variety of tissues. Biological actions of NTPDases are a consequence (at least in part) of the regulated phosphohydrolytic activity on extracellular nucleotides and consequent effects on P2-receptor signaling. It further appears that the spatial and temporal expression of NTPDases by various cell types within the vasculature, the nervous tissues and other tissues impacts on several patho-physiological processes. Examples include acute effects on cellular metabolism, adhesion, activation and migration with other protracted impacts upon developmental responses, inclusive of cellular proliferation, differentiation and apoptosis, as seen with atherosclerosis, degenerative neurological diseases and immune rejection of transplanted organs and cells. Future clinical applications are expected to involve the development of new therapeutic strategies for transplantation and various inflammatory cardiovascular, gastrointestinal and neurological diseases.
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Affiliation(s)
- Simon C. Robson
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts USA
| | - Jean Sévigny
- Centre de Recherche en Rhumatologie et Immunologie, Université Laval, Québec, Québec Canada
| | - Herbert Zimmermann
- Institut fuer Zellbiologie und Neurowissenschaft, Biozentrum der J.W. Goethe-Universitaet, Marie-Curie-Str. 9, D-60439 Frankfurt am Main, Germany
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Song CJ, Steinebrunner I, Wang X, Stout SC, Roux SJ. Extracellular ATP induces the accumulation of superoxide via NADPH oxidases in Arabidopsis. PLANT PHYSIOLOGY 2006; 140:1222-32. [PMID: 16428598 PMCID: PMC1435826 DOI: 10.1104/pp.105.073072] [Citation(s) in RCA: 210] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Extracellular ATP can serve as a signaling agent in animal cells, and, as suggested by recent reports, may also do so in plant cells. In animal cells it induces the production of reactive oxygen species through the mediation of NADPH oxidase. Similarly, here we report that in leaves of Arabidopsis (Arabidopsis thaliana), applied ATP, but not AMP or phosphate, induces the accumulation of superoxide (O2-) in a biphasic, dose-dependent manner, with a threshold at 500 nm ATP. This effect did not require ATP hydrolysis for it was mimicked by ATPgammaS. ATP also induced increased levels of Arabidopsis respiratory burst oxidase homolog D (AtrbohD) mRNA, but ATP-treated plants that had disrupted AtrbohD and AtrbohF genes did not accumulate O2-, indicating that NADPH oxidases are responsible for the induced O2- accumulation. Inhibitors of mammalian P2-type ATP receptors abolished ATP-induced O2- production, suggesting that the ATP effects may be mediated through P2-like receptors in plants. Cytosolic Ca2+ and calmodulin are likely to help transduce the ATP responses, as they do in animal cells, because a Ca2+ channel blocker, a Ca2+ chelator, and calmodulin antagonist all reduced ATP-induced O2- accumulation. Furthermore, ATP treatment enhanced the expression of genes that are induced by wounds and other stresses. The ATP measured at wound sites averaged 40 microm, well above the level needed to induce O2- accumulation and gene expression changes. Transgenic plants overexpressing an apyrase gene had reduced O2- production in response to applied ATP and wounding. Together, these data suggest a possible role for extracellular ATP as a signal potentially in wound and stress responses.
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Affiliation(s)
- Charlotte J Song
- Section of Molecular Cell and Developmental Biology, University of Texas, Austin, Texas 78712, USA
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Silva AC, Morsch ALB, Zanin RF, Corrêa MC, Arantes LC, Araujo MC, Morsch VM, Schetinger MRC. Enzymes that hydrolyze adenine nucleotides in chronic renal failure: relationship between hemostatic defects and renal failure severity. Biochim Biophys Acta Mol Basis Dis 2006; 1741:282-8. [PMID: 16019192 DOI: 10.1016/j.bbadis.2005.06.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2004] [Revised: 06/08/2005] [Accepted: 06/08/2005] [Indexed: 11/28/2022]
Abstract
The activities of the enzymes NTPDase (E.C.3.6.1.5, apyrase, ATP diphosphohydrolase, ecto-CD 39) and 5'-nucleotidase (E.C.3.1.3.5, CD 73) were analyzed in platelets from patients with chronic renal failure (CRF), both undergoing hemodialysis treatment (HD) and not undergoing hemodialysis (ND), as well as from a control group. The results showed an increase in platelet NTPDase activity in CRF patients on HD treatment (52.88%) with ATP as substrate (P<0.0001). ADP hydrolysis was decreased (33.68% and 39.75%) in HD and ND patients, respectively. In addition, 5'-nucleotidase activity was elevated in the HD (160%) and ND (81.49%) groups when compared to the control (P<0.0001). Significant correlation was found among ATP, ADP and AMP hydrolysis and plasma creatinine and urea levels (P<0.0001). Patients were compared statistically according the time of hemodialysis treatment. We found enhanced NTPDase and 5'-nucleotidase activities between 49 and 72 months on HD patients. Our result suggests the existence of alterations in nucleotide hydrolysis in platelets of CRF patients. Possibly, this altered nucleotide hydrolysis could contribute to hemostasis abnormalities found in CRF.
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Affiliation(s)
- Adriane C Silva
- Departamento de Química, Centro de Ciências Naturais e Exatas, Universidade Federal de Santa Maria, Avenue Roraima, 97105-900, Santa Maria, RS, Brazil
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Entringer PF, Gondim KC, Meyer-Fernandes JR. Ecto-nucleotidase activities in the fat body of Rhodnius prolixus. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2006; 61:1-9. [PMID: 16380977 DOI: 10.1002/arch.20087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
In this study, we describe the ability of intact fat body of an insect, Rhodnius prolixus, to hydrolyze extracellular ATP. In these fat bodies, the ATP hydrolysis was low in the absence of any divalent metal, and was stimulated by MgCl(2). Both activities (in the absence or presence of MgCl(2)) were linear with time for at least 30 min. In order to confirm the observed nucleotidase activities as ecto-nucleotidases, we used an impermeant inhibitor, DIDS (4, 4'-diisothiocyanostylbene 2'-2'-disulfonic acid). This reagent inhibited both nucleotidase activities and its inhibitory effect was suppressed by ATP. Both ecto-nucleotidase activities were insensitive to inhibitors of other ATPase and phosphatase activities, such as oligomycin, sodium azide, bafilomycin, ouabain, vanadate, molybdate, sodium fluoride, levamizole, tartrate, p-NPP, sodium phosphate, and suramin. Concanavalin A, activator of some ecto-ATPases, was able to stimulate the Mg(2+)-independent nucleotidase activity, but not the Mg(2+)-dependent one. The Mg(2+)-independent nucleotidase activity was enhanced with increases in the pH in the range between 6.4-8.0, but the Mg(2+)-dependent nucleotidase activity was not affected. Besides MgCl(2) , the ecto-ATPase activity was also stimulated by CaCl(2),() MnCl(2), and SrCl(2), but not by ZnCl(2). ATP, ADP, and AMP were the best substrates for the Mg(2+)-dependent ecto-nucleotidase activity, and CTP, GTP, and UTP produced very low reaction rates. However, the Mg(2+)-independent nucleotidase activity recognized all these nucleotides producing similar reaction rates, but GTP was a less efficient substrate. The possible role of the two ecto-nucleotidase activities present on the cell surface of fat body of Rhodnius prolixus, which are distinguished by their substrate specificity and their response to Mg(2+), is discussed.
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Affiliation(s)
- Petter F Entringer
- Instituto de Bioquímica Médica, Universidade Federal do Rio de Janeiro, CCS, Bloco H, sala H2-013, Ilha do Fundão, 21941-590 Rio de Janeiro, Brazil
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Czarnecka J, Cieślak M, Michał K. Application of solid phase extraction and high-performance liquid chromatography to qualitative and quantitative analysis of nucleotides and nucleosides in human cerebrospinal fluid. J Chromatogr B Analyt Technol Biomed Life Sci 2005; 822:85-90. [PMID: 15993662 DOI: 10.1016/j.jchromb.2005.05.026] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2004] [Revised: 05/06/2005] [Accepted: 05/15/2005] [Indexed: 11/20/2022]
Abstract
New method of qualitative and quantitative analysis of nucleotides in human cerebrospinal fluid (CSF), based on the combination of extraction of purines and pyrimidines to the solid phase (SPE) and high-performance liquid chromatography (HPLC), was proposed. Use of SPE and lyophilization of samples allowed for the first time to detect the presence of di- and triphosphonucleotides in human CSF. Concentration of those compounds varied from 0.003 to 5.0 microM. Differences in the nucleotide mixture composition in human CSF detected with the new method are coupled with the neurological disorders and might be a basis for an efficient diagnostic tool.
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Affiliation(s)
- Joanna Czarnecka
- Biochemistry Department, Nicolaus Copernicus University, 9 Gagarina St, 87-100 Toruń, Poland
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Burrell HE, Wlodarski B, Foster BJ, Buckley KA, Sharpe GR, Quayle JM, Simpson AWM, Gallagher JA. Human keratinocytes release ATP and utilize three mechanisms for nucleotide interconversion at the cell surface. J Biol Chem 2005; 280:29667-76. [PMID: 15958381 DOI: 10.1074/jbc.m505381200] [Citation(s) in RCA: 99] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Nucleotide activation of P2 receptors is important in autocrine and paracrine regulation in many tissues. In the epidermis, nucleotides are involved in proliferation, differentiation, and apoptosis. In this study, we have used a combination of luciferin-luciferase luminometry, pharmacological inhibitors, and confocal microscopy to demonstrate that HaCaT keratinocytes release ATP into the culture medium, and that there are three mechanisms for nucleotide interconversion, resulting in ATP generation at the cell surface. Addition of ADP, GTP, or UTP to culture medium elevated the ATP concentration. ADP to ATP conversion was inhibited by diadenosine pentaphosphate, oligomycin, and UDP, suggesting the involvement of cell surface adenylate kinase, F(1)F(0) ATP synthase, and nucleoside diphosphokinase (NDPK), respectively, which was supported by immunohistochemistry. Simultaneous addition of ADP and GTP elevated ATP above that for each nucleotide alone indicating that GTP acts as a phosphate donor. However, the activity of NDPK, F(1)F(0) ATP synthase or the forward reaction of adenylate kinase could not fully account for the culture medium ATP content. We postulate that this discrepancy is due to the reverse reaction of adenylate kinase utilizing AMP. In normal human skin, F(1)F(0) ATP synthase and NDPK were differentially localized, with mitochondrial expression in the basal layer, and cell surface expression in the differentiated layers. We and others have previously demonstrated that keratinocytes express multiple P2 receptors. In this study we now identify the potential sources of extracellular ATP required to activate these receptors and provide better understanding of the role of nucleotides in normal epidermal homeostasis and wound healing.
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Affiliation(s)
- Helen E Burrell
- Department of Human Anatomy & Cell Biology, School of Biomedical Sciences, University of Liverpool, The Sherrington Buildings, UK.
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Tuytten R, Lemière F, Van Dongen W, Slegers H, Newton RP, Esmans EL. Investigation of the use of immobilised metal affinity chromatography for the on-line sample clean up and pre-concentration of nucleotides prior to their determination by ion pair liquid chromatography-electrospray mass spectrometry: a pilot study. J Chromatogr B Analyt Technol Biomed Life Sci 2005; 809:189-98. [PMID: 15315764 DOI: 10.1016/j.jchromb.2004.06.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2003] [Revised: 06/01/2004] [Accepted: 06/07/2004] [Indexed: 11/19/2022]
Abstract
This study explored an alternative way to enrich and pre-purify biological samples containing nucleoside mono-, di- and triphosphates. These compounds were trapped by immobilised metal affinity chromatography (IMAC) on a Poros 20 MC IMAC-column, which was conditioned with Fe3+. The IMAC-column was implemented in a column switching set-up separating nucleoside mono-, di- and triphosphates on a Hypersil ODS 35 mm x 0.3 mm capillary column hyphenated to electrospray mass spectrometry resulting in the first miniaturised column switching liquid chromatography-mass spectrometry (LC-MS) system for nucleotides.
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Affiliation(s)
- Robin Tuytten
- The Nucleoside Research and Mass Spectrometry Unit, Department of Chemistry, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium
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Görgen M, Turatti K, Medeiros AR, Buffon A, Bonan CD, Sarkis JJF, Pereira GS. Aqueous extract of Ilex paraguariensis decreases nucleotide hydrolysis in rat blood serum. JOURNAL OF ETHNOPHARMACOLOGY 2005; 97:73-77. [PMID: 15652278 DOI: 10.1016/j.jep.2004.10.015] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2004] [Revised: 09/24/2004] [Accepted: 10/18/2004] [Indexed: 05/24/2023]
Abstract
Mate is a xanthine-containing beverage, which is prepared as an infusion of the dried and ground leaves of Ilex paraguariensis St. Hil. (Aquifoliacea). Previous reports have shown that Ilex paraguariensis has the highest levels of caffeine and theobromine when compared to other Ilex species. Furthermore, mate is able to interfere in the circulatory system, acting as a diuretic and hypotensive agent. Many processes of vascular injury result in the release of adenine nucleotides, which exert a variety of effects. Nucleoside 5' tri- and diphosphates may be hydrolyzed by members of the ecto-nucleoside triphosphate diphosphohydrolase (E-NTPDase) family. The synchronic action of a NTPDase and a 5'-nucleotidase promotes the catabolism of ATP to adenosine, which is able to control the extracellular nucleotides/nucleosides ratio. The chronic ingestion of aqueous extract of Ilex paraguariensis by rats during 15 days significantly decreased ATP (55%), ADP (50%) and AMP (40%) hydrolysis in blood serum. These results suggest changes in the balance of purine levels induced by Ilex paraguariensis ingestion. Considering the potential effects of Ilex paraguariensis in the circulatory system, these results may be relevant since NTPDases are a novel drug target for the treatment of cardiovascular diseases.
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Affiliation(s)
- Milena Görgen
- Laboratório de Bioquímica, UNIVATES Centro Universitário, Lajeado, Rua Avelino Tallini, 171 CEP: 95900-000 Caixa Posta 155, Lajeado, RS, Brazil
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Kukulski F, Sévigny J, Komoszyński M. Comparative hydrolysis of extracellular adenine nucleotides and adenosine in synaptic membranes from porcine brain cortex, hippocampus, cerebellum and medulla oblongata. Brain Res 2005; 1030:49-56. [PMID: 15567336 DOI: 10.1016/j.brainres.2004.09.044] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/24/2004] [Indexed: 11/17/2022]
Abstract
We have investigated the metabolism of extracellular adenine nucleotides and adenosine in porcine brain. The cortex synaptic plasma membranes hydrolyzed ATP to ADP, AMP and adenosine. We also observed a slow hydrolysis of adenosine with the concomitant accumulation of inosine. These results indicate that NTPDase1, NTPDase2, ecto-5'-nucleotidase, and adenosine deaminase are present in cortex synaptic membranes from porcine brain. We further showed that all these enzymes are also abundant in synaptic membranes from hippocampus, cerebellum, and medulla oblongata and compared their specific activities. Brain cortex and hippocampus exhibited higher activities of NTPDase1 and NTPDase2 than cerebellum and medulla oblongata. It was consistent with the high level of the expression of NTPDases in the two first structures. Adenosine deaminase activity was found in all brain structures analyzed; however, it was lower than the activity of ecto-nucleotidases. Taken together, our data suggest that investigated enzymes have a ubiquitous abundance in porcine brain, and observed differences in their activities in cortex, hippocampus, cerebellum, and medulla oblongata may correlate with the pattern of P2 receptor expression in these brain areas. In addition, low activity of adenosine deaminase may indicate that nonenzymatic mechanism(s) are responsible for the termination of P1 receptor signaling in porcine brain.
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Affiliation(s)
- Filip Kukulski
- Department of Biochemistry, Institute of General and Molecular Biology, N. Copernicus University of Toruń, Toruń, Poland.
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Sissons J, Alsam S, Jayasekera S, Khan NA. Ecto-ATPases of clinical and non-clinical isolates of Acanthamoeba. Microb Pathog 2004; 37:231-9. [PMID: 15519044 DOI: 10.1016/j.micpath.2004.01.004] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2003] [Revised: 01/06/2004] [Accepted: 01/06/2004] [Indexed: 11/28/2022]
Abstract
Acanthamoeba are opportunistic protozoan parasites that can cause fatal granulomatous amoebic encephalitis and eye keratitis, however the pathogenic mechanisms of Acanthamoeba remain unclear. In this study, we described the ability of live Acanthamoeba to hydrolyse extracellular ATP. Both clinical and non-clinical isolates belonging to genotypes, T1, T2, T3, T4 and T7 exhibited ecto-ATPase activities in vitro. Using non-denaturing polyacrylamide gel electrophoresis, ecto-ATPases were further characterized. All Acanthamoeba isolates tested, exhibited a single ecto-ATPase band (approximate molecular weight of 272 kDa). However, clinical isolates exhibited additional bands suggesting that ecto-ATPases may play a role in the pathogenesis of Acanthamoeba. This was supported using suramin (ecto-ATPase inhibitor), which inhibited Acanthamoeba-induced host cell cytotoxicity. Previously, we and others have shown that Acanthamoeba binds to host cells using their mannose-binding protein and binding can be blocked using exogenous alpha-mannose. In this study, we observed that alpha-mannose significantly increased ecto-ATPase activities of pathogenic Acanthamoeba belonging to T1, T2, T3 and T4 genotypes but had no effect on non-pathogenic Acanthamoeba (belonging to T7 genotype). Overall, we have shown, for the first time, that Acanthamoeba exhibit ecto-ATPase activities, which may play a role in the pathogenesis of Acanthamoeba as well as their potential role in the differentiation of pathogenic Acanthamoeba.
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Affiliation(s)
- James Sissons
- School of Biological and Chemical Sciences, Birkbeck College, University of London, London WC1E 7HX, UK
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Borges E, Vuaden FC, Cognato GDP, Fauth MDG, Bonan CD, Turcato G, Rossi ICDC, Dias RD. Effects of starvation on haemolymphatic glucose levels, glycogen contents and nucleotidase activities in different tissues ofHelix aspersa(Müller, 1774) (mollusca, gastropoda). ACTA ACUST UNITED AC 2004; 301:891-7. [PMID: 15673110 DOI: 10.1002/jez.a.121] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
In the present study, the glucose concentration in the haemolymph and glycogen levels were determined in the various body parts of the Helix aspersa snail after feeding lettuce ad libitum and after various periods of starvation. To characterize the effect of starvation on nucleotidase activity, enzyme assays were performed on membranes of the nervous ganglia and digestive gland. Results demonstrated the maintenance of the haemolymph glucose concentration for up to 30 days of starvation, probably due to the consumption of glycogen from the mantle. In the nervous ganglia, depletion of glycogen occurs progressively during the different periods of starvation. No significant changes were observed on ATP and ADP hydrolysis in the membranes of nervous ganglia and no alterations in Ca2+ -ATPase and Mg2+ -ATPase occurred in the membranes of the digestive gland of H. aspersa during the different periods of starvation. Although there were no changes in the enzyme activities during starvation, they could be modulated by effectors in situ with concomitant changes in products/reactants during starvation.
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Affiliation(s)
- Eliane Borges
- Laboratório de Pesquisa Bioquímica, Departamento de Ciências Fisiológicas, Faculdade de Biociências, Pontifícia Universidade Católica do Rio Grande do Sul, Caixa postal 1429, 90619-900, Porto Alegre, RS, Brazil
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Tasca T, Bonan CD, Carli GAD, Battastini AMO, Sarkis JJF. Characterization of an ecto-5'-nucleotidase (EC 3.1.3.5) activity in intact cells of Trichomonas vaginalis. Exp Parasitol 2004; 105:167-73. [PMID: 14969694 DOI: 10.1016/j.exppara.2003.12.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2003] [Revised: 09/02/2003] [Accepted: 12/01/2003] [Indexed: 11/16/2022]
Abstract
The enzymatic properties of an ecto-5'-nucleotidase were described in Trichomonas vaginalis. The enzyme hydrolyzes nucleoside monophosphates in optimum pH values of 7.5 and 6.5 for the 30236 strain and for the 30238 strain, respectively. Mg(2+) and Ca(2+) were activators of AMP hydrolysis in both strains. The apparent K(m) (Michaelis constant) values for Mg(2+)-AMP were 111.4+/-28.1 microM (mean+/-SD, n=3) for 30236 strain and 420.2+/-35.7 microM (mean+/-SD, n=3) for 30238 strain. The ecto-5'-nucleotidase activity was insensitive to levamisole and tetramisole, inhibitors of alkaline phosphatases, whereas alpha,beta-methylene-ADP inhibited the enzymatic activity of both strains. Our results showed that the AMP hydrolysis presents differences in some kinetic parameters between the two strains investigated. An analysis of the enzymatic chain involved in the ATP hydrolysis to adenosine will contribute to understanding the biochemical aspects of the parasite and the mechanisms related to host-parasite interactions.
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Affiliation(s)
- Tiana Tasca
- Departamento de Bioquímica, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
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Burnstock G, Knight GE. Cellular Distribution and Functions of P2 Receptor Subtypes in Different Systems. INTERNATIONAL REVIEW OF CYTOLOGY 2004; 240:31-304. [PMID: 15548415 DOI: 10.1016/s0074-7696(04)40002-3] [Citation(s) in RCA: 581] [Impact Index Per Article: 29.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
This review is aimed at providing readers with a comprehensive reference article about the distribution and function of P2 receptors in all the organs, tissues, and cells in the body. Each section provides an account of the early history of purinergic signaling in the organ?cell up to 1994, then summarizes subsequent evidence for the presence of P2X and P2Y receptor subtype mRNA and proteins as well as functional data, all fully referenced. A section is included describing the plasticity of expression of P2 receptors during development and aging as well as in various pathophysiological conditions. Finally, there is some discussion of possible future developments in the purinergic signaling field.
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Affiliation(s)
- Geoffrey Burnstock
- Autonomic Neuroscience Institute, Royal Free and University College Medical School, London NW3 2PF, United Kingdom
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Tasca T, Borges FP, Bonan CD, De Carli GA, Battastini AMO, Sarkis JJF. Effects of metronidazole and tinidazole on NTPDase1 and ecto-5'-nucleotidase from intact cells of Trichomonas vaginalis. FEMS Microbiol Lett 2003; 226:379-84. [PMID: 14553936 DOI: 10.1016/s0378-1097(03)00637-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Here we report the effects of metronidazole and tinidazole on NTPDase1 and ecto-5'-nucleotidase from intact cells of Trichomonas vaginalis. Adenosine triphosphate (ATP) and adenosine diphosphate (ADP) hydrolysis was 5- to 7-fold higher for the fresh clinical strain, when compared with the ATCC (American Type Culture Collection) strain. ATP hydrolysis was activated in the presence of metronidazole in the ATCC strain, whilst it was inhibited 33% by 50 microM tinidazole in a fresh clinical isolate. The treatment of cells in the presence of metronidazole for 2 h inhibited ATP and ADP hydrolysis, whilst treatment with tinidazole inhibited ATP and ADP hydrolysis only in the fresh clinical isolate. The drugs did not change the ecto-5'-nucleotidase activity for both strains. Our results suggest that the modulation of extracellular ATP and ADP levels during treatment with these drugs could be a parasitic defence strategy as a survival mechanism in an adverse environment.
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Affiliation(s)
- Tiana Tasca
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos 2600-Anexo, 90035-003 Porto Alegre, RS, Brazil
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Picher M, Graff RD, Lee GM. Extracellular nucleotide metabolism and signaling in the pathophysiology of articular cartilage. ACTA ACUST UNITED AC 2003; 48:2722-36. [PMID: 14558075 DOI: 10.1002/art.11289] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Maryse Picher
- School of Medicine, University of North Carolina, Chapel Hill 27599, USA.
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Pintor J, Peláez T, Peral A. Adenosine tetraphosphate, Ap4, a physiological regulator of intraocular pressure in normotensive rabbit eyes. J Pharmacol Exp Ther 2003; 308:468-73. [PMID: 14600249 DOI: 10.1124/jpet.103.058669] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Adenosine 5' tetraphosphate, Ap(4), is a natural nucleotide present in many biological systems. This nucleotide has been found as a constituent of the nucleotide pool present in the aqueous humor of New Zealand rabbits. HPLC analysis confirmed its identity and calculated its concentration levels to be 197 +/- 21 nM. When applied topically to the rabbit eyes, this mononucleotide produced a reduction in the intraocular pressure, which was dose-dependent. The pD(2) value calculated from the dose-response curve was 7.28 +/- 0.47, which is equivalent to 52.48 nM. The time course of such intraocular pressure reduction presented a maximal decrease of IOP to 75.1 +/- 2.3% compared with the vehicle control value (100%), and the effect lasted for more than 2 h. Cross-desensitization studies demonstrated that Ap(4) effect was mediated via a P2X receptor in this system. P2 receptor antagonists suramin, pyridoxal phosphate 6-azophenyl-2',4'-disulfonic acid (PPADS), and reactive blue 2 (RB-2) showed that only the latter was able to revert the effect of Ap(4). Antagonists of adrenoceptors and cholinoceptors were able to partially reverse the effect of this nucleotide; this might indicate a connection with the neural mechanisms that control the intraocular pressure.
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Affiliation(s)
- Jesús Pintor
- Departmentos de Bioquimica, Escuela Universitaria Optica, Universidad Complutense de Madrid, Spain.
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Fujii Y, Nomura T, Yokoyama R, Shinoda S, Okamoto K. Studies of the mechanism of action of the aerolysin-like hemolysin of Aeromonas sobria in stimulating T84 cells to produce cyclic AMP. Infect Immun 2003; 71:1557-60. [PMID: 12595476 PMCID: PMC148825 DOI: 10.1128/iai.71.3.1557-1560.2003] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We previously reported that the aerolysin-like hemolysin of Aeromonas sobria stimulates T84 cells to produce cyclic AMP, which then emerges in the culture medium. In order to clarify the mechanism of action of the hemolysin, we examined the involvement of adenosine nucleotide. The results show that the hemolysin stimulates T84 cells to release ATP, which is then converted to adenosine by ectonucleotidase. The adenosine generated might stimulate the P1 adenosine receptors of T84 cells to produce cyclic AMP.
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Affiliation(s)
- Yoshio Fujii
- Institute of Pharmacognosy, Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Yamashiro, Tokushima, Tokushima 770-8514, Japan.
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