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Yoo E, Choe D, Shin J, Cho S, Cho BK. Mini review: Enzyme-based DNA synthesis and selective retrieval for data storage. Comput Struct Biotechnol J 2021; 19:2468-2476. [PMID: 34025937 PMCID: PMC8113751 DOI: 10.1016/j.csbj.2021.04.057] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 04/20/2021] [Accepted: 04/22/2021] [Indexed: 11/26/2022] Open
Abstract
The market for using and storing digital data is growing, with DNA synthesis emerging as an efficient way to store massive amounts of data. Storing information in DNA mainly consists of two steps: data writing and reading. The writing step requires encoding data in DNA, building one nucleotide at a time as a form of single-stranded DNA (ssDNA). Once the data needs to be read, the target DNA is selectively retrieved and sequenced, which will also be in the form of an ssDNA. Recently, enzyme-based DNA synthesis is emerging as a new method to be a breakthrough on behalf of decades-old chemical synthesis. A few enzymatic methods have been presented for data memory, including the use of terminal deoxynucleotidyl transferase. Besides, enzyme-based amplification or denaturation of the target strand into ssDNA provides selective access to the desired dataset. In this review, we summarize diverse enzymatic methods for either synthesizing ssDNA or retrieving the data-containing DNA.
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Affiliation(s)
- Eojin Yoo
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
| | - Donghui Choe
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
| | - Jongoh Shin
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
| | - Suhyung Cho
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea.,Innovative Biomaterials Research Center, KI for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
| | - Byung-Kwan Cho
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea.,Innovative Biomaterials Research Center, KI for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
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2
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Yang J, Li K, Li C, Gu J. Intrinsic Apyrase-Like Activity of Cerium-Based Metal-Organic Frameworks (MOFs): Dephosphorylation of Adenosine Tri- and Diphosphate. Angew Chem Int Ed Engl 2020; 59:22952-22956. [PMID: 32902900 DOI: 10.1002/anie.202008259] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Indexed: 12/15/2022]
Abstract
Apyrase is an important family of extracellular enzymes that catalyse the hydrolysis of high-energy phosphate bonds (HEPBs) in ATP and ADP, thereby modulating many physiological processes and driving life activities. Herein, we report an unexpected discovery that cerium-based metal-organic frameworks (Ce-MOFs) of UiO-66(Ce) have intrinsic apyrase-like activity for ATP/ADP-related physiological processes. The abundant CeIII /CeIV couple sites of Ce-MOFs endow them with the ability to selectively catalyse the hydrolysis of HEPBs of ATP and ADP under physiological conditions. Compared to natural enzymes, they could resist extreme pH and temperature, and present a broad range of working conditions. Based on this finding, a significant inhibitory effect on ADP-induced platelet aggregation was observed upon exposing the platelet-rich plasma (PRP) to the biomimetic UiO-66(Ce) films, prefiguring their wide application potentials in medicine and biotechnology.
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Affiliation(s)
- Jian Yang
- Shanghai Engineering Research Center of Hierarchical Nanomaterials, School of Materials Science and Engineering, East China University of Science and Technology, Shanghai, 200237, China
| | - Ke Li
- Shanghai Engineering Research Center of Hierarchical Nanomaterials, School of Materials Science and Engineering, East China University of Science and Technology, Shanghai, 200237, China
| | - Chunzhong Li
- Shanghai Engineering Research Center of Hierarchical Nanomaterials, School of Materials Science and Engineering, East China University of Science and Technology, Shanghai, 200237, China
| | - Jinlou Gu
- Shanghai Engineering Research Center of Hierarchical Nanomaterials, School of Materials Science and Engineering, East China University of Science and Technology, Shanghai, 200237, China
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3
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Yang J, Li K, Li C, Gu J. Intrinsic Apyrase‐Like Activity of Cerium‐Based Metal–Organic Frameworks (MOFs): Dephosphorylation of Adenosine Tri‐ and Diphosphate. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202008259] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Jian Yang
- Shanghai Engineering Research Center of Hierarchical Nanomaterials School of Materials Science and Engineering East China University of Science and Technology Shanghai 200237 China
| | - Ke Li
- Shanghai Engineering Research Center of Hierarchical Nanomaterials School of Materials Science and Engineering East China University of Science and Technology Shanghai 200237 China
| | - Chunzhong Li
- Shanghai Engineering Research Center of Hierarchical Nanomaterials School of Materials Science and Engineering East China University of Science and Technology Shanghai 200237 China
| | - Jinlou Gu
- Shanghai Engineering Research Center of Hierarchical Nanomaterials School of Materials Science and Engineering East China University of Science and Technology Shanghai 200237 China
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4
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Zhong EH, Ledderose C, De Andrade Mello P, Enjyoji K, Lunderberg JM, Junger W, Robson SC. Structural and functional characterization of engineered bifunctional fusion proteins of CD39 and CD73 ectonucleotidases. Am J Physiol Cell Physiol 2020; 320:C15-C29. [PMID: 33052071 DOI: 10.1152/ajpcell.00430.2020] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Extracellular diphosphate and triphosphate nucleotides are released from activated or injured cells to trigger vascular and immune P2 purinergic receptors, provoking inflammation and vascular thrombosis. These metabokines are scavenged by ectonucleoside triphosphate diphosphohydrolase-1 (E-NTPDase1 or CD39). Further degradation of the monophosphate nucleoside end products occurs by surface ecto-5'-nucleotidase (NMPase) or CD73. These ectoenzymatic processes work in tandem to promote adenosinergic responses, which are immunosuppressive and antithrombotic. These homeostatic ectoenzymatic mechanisms are lost in the setting of oxidative stress, which exacerbates inflammatory processes. We have engineered bifunctional enzymes made up from ectodomains (ECDs) of CD39 and CD73 within a single polypeptide. Human alkaline phosphatase-ectodomain (ALP-ECD) and human acid phosphatase-ectodomain (HAP-ECD) fusion proteins were also generated, characterized, and compared with these CD39-ECD, CD73-ECD, and bifunctional fusion proteins. Through the application of colorimetrical functional assays and high-performance liquid chromatography kinetic assays, we demonstrate that the bifunctional ectoenzymes express high levels of CD39-like NTPDase activity and CD73-like NMPase activity. Chimeric CD39-CD73-ECD proteins were superior in converting triphosphate and diphosphate nucleotides into nucleosides when compared with ALP-ECD and HAP-ECD. We also note a pH sensitivity difference between the bifunctional fusion proteins and parental fusions, as well as ectoenzymatic property distinctions. Intriguingly, these innovative reagents decreased platelet activation to exogenous agonists in vitro. We propose that these chimeric fusion proteins could serve as therapeutic agents in inflammatory diseases, acting to scavenge proinflammatory ATP and also generate anti-inflammatory adenosine.
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Affiliation(s)
- Elizabeth H Zhong
- Department of Anesthesia, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts.,Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts
| | - Carola Ledderose
- Department of Surgery, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts
| | - Paola De Andrade Mello
- Department of Anesthesia, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts.,Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts
| | - Keiichi Enjyoji
- Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts
| | - Justin Mark Lunderberg
- Department of Anesthesia, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts
| | - Wolfgang Junger
- Department of Surgery, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts
| | - Simon C Robson
- Department of Anesthesia, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts.,Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts
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5
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Jeffrey JL, Lawson KV, Powers JP. Targeting Metabolism of Extracellular Nucleotides via Inhibition of Ectonucleotidases CD73 and CD39. J Med Chem 2020; 63:13444-13465. [PMID: 32786396 DOI: 10.1021/acs.jmedchem.0c01044] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
In the tumor microenvironment, unusually high concentrations of extracellular adenosine promote tumor proliferation through various immunosuppressive mechanisms. Blocking adenosine production by inhibiting nucleotide-metabolizing enzymes, such as ectonucleotidases CD73 and CD39, represents a promising therapeutic strategy that may synergize with other immuno-oncology mechanisms and chemotherapies. Emerging small-molecule ectonucleotidase inhibitors have recently entered clinical trials. This Perspective will outline challenges, strategies, and recent advancements in targeting this class with small-molecule inhibitors, including AB680, the first small-molecule CD73 inhibitor to enter clinical development. Specific case studies, including structure-based drug design and lead optimization, will be outlined. Preclinical data on these molecules and their ability to enhance antitumor immunity will be discussed.
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Affiliation(s)
- Jenna L Jeffrey
- Arcus Biosciences, 3928 Point Eden Way, Hayward, California 94545, United States
| | - Kenneth V Lawson
- Arcus Biosciences, 3928 Point Eden Way, Hayward, California 94545, United States
| | - Jay P Powers
- Arcus Biosciences, 3928 Point Eden Way, Hayward, California 94545, United States
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6
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Silkin YA, Silkina EN, Silkin MY. A Study of Some Biochemical Properties of Ecto-ATPase (Nucleotidase) in Erythrocytes of the Black Sea Thornback Ray Raja clavata L. J EVOL BIOCHEM PHYS+ 2020. [DOI: 10.1134/s0022093020010044] [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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7
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Mishra A, Korlepara DB, Kumar M, Jain A, Jonnalagadda N, Bejagam KK, Balasubramanian S, George SJ. Biomimetic temporal self-assembly via fuel-driven controlled supramolecular polymerization. Nat Commun 2018; 9:1295. [PMID: 29602946 PMCID: PMC5878180 DOI: 10.1038/s41467-018-03542-z] [Citation(s) in RCA: 134] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Accepted: 02/22/2018] [Indexed: 12/26/2022] Open
Abstract
Temporal control of supramolecular assemblies to modulate the structural and transient characteristics of synthetic nanostructures is an active field of research within supramolecular chemistry. Molecular designs to attain temporal control have often taken inspiration from biological assemblies. One such assembly in Nature which has been studied extensively, for its well-defined structure and programmable self-assembly, is the ATP-driven seeded self-assembly of actin. Here we show, in a synthetic manifestation of actin self-assembly, an ATP-selective and ATP-fuelled, controlled supramolecular polymerization of a phosphate receptor functionalised monomer. It undergoes fuel-driven nucleation and seeded growth that provide length control and narrow dispersity of the resultant assemblies. Furthermore, coupling via ATP-hydrolysing enzymes yielded its transient characteristics. These results will usher investigations into synthetic analogues of important biological self-assembly motifs and will prove to be a significant advancement toward biomimetic temporally programmed materials.
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Affiliation(s)
- Ananya Mishra
- Supramolecular Chemistry Laboratory, New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur, Bangalore, 560064, India
| | - Divya B Korlepara
- Molecular Simulations Laboratory, Chemistry and Physics of Materials Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur, Bangalore, 560064, India
| | - Mohit Kumar
- Supramolecular Chemistry Laboratory, New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur, Bangalore, 560064, India
| | - Ankit Jain
- Supramolecular Chemistry Laboratory, New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur, Bangalore, 560064, India
| | - Narendra Jonnalagadda
- Supramolecular Chemistry Laboratory, New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur, Bangalore, 560064, India
| | - Karteek K Bejagam
- Molecular Simulations Laboratory, Chemistry and Physics of Materials Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur, Bangalore, 560064, India
| | - Sundaram Balasubramanian
- Molecular Simulations Laboratory, Chemistry and Physics of Materials Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur, Bangalore, 560064, India.
| | - Subi J George
- Supramolecular Chemistry Laboratory, New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur, Bangalore, 560064, India.
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8
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Silkin YA, Silkina EN. The role of ecto-ATPases of erythrocyte plasma membrane in hemodynamics of fishes. J EVOL BIOCHEM PHYS+ 2017. [DOI: 10.1134/s0022093017010094] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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9
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Chen TR, Urban PL. Mass spectrometry-guided refinement of chemical energy buffers. Proc Math Phys Eng Sci 2016; 472:20150812. [PMID: 27436961 PMCID: PMC4950186 DOI: 10.1098/rspa.2015.0812] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Accepted: 05/24/2016] [Indexed: 11/12/2022] Open
Abstract
Biocatalytic reactions often require supplying chemical energy and phosphate groups in the form of adenosine triphosphate (ATP). Auxiliary enzymes can be used to convert a reaction by-product-adenosine diphosphate (ADP)-back to ATP. By employing real-time mass spectrometry (RTMS), one can gain an insight into inter-conversions of reactants in multi-enzyme reaction systems and optimize the reaction conditions. In this study, temporal traces of ions corresponding to adenosine monophosphate (AMP), ADP and ATP provided vital information that could be used to adjust activities of the 'buffering enzymes'. Using the RTMS results as a feedback, we also characterized a bienzymatic energy buffer that enables the recovery of ATP in the cases where it is directly hydrolysed to AMP in the main enzymatic reaction. The significance of careful selection of enzyme activities-guided by RTMS-is exemplified in the synthesis of glucose-6-phosphate by hexokinase in the presence of a buffering enzyme, pyruvate kinase. Relative activities of the two enzymes, present in the reaction mixture, influence biosynthetic reaction yields. This observation supports the conclusion that optimization of chemical energy recycling procedures is critical for the biosynthetic reaction economy.
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Affiliation(s)
- T.-R. Chen
- Department of Applied Chemistry, National Chiao Tung University, 1001 University Road, Hsinchu 300, Taiwan
| | - P. L. Urban
- Department of Applied Chemistry, National Chiao Tung University, 1001 University Road, Hsinchu 300, Taiwan
- Institute of Molecular Science, National Chiao Tung University, 1001 University Road, Hsinchu 300, Taiwan
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10
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Ectonucleotidases in solid organ and allogeneic hematopoietic cell transplantation. J Biomed Biotechnol 2012; 2012:208204. [PMID: 23125523 PMCID: PMC3482062 DOI: 10.1155/2012/208204] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2012] [Accepted: 07/10/2012] [Indexed: 01/27/2023] Open
Abstract
Extracellular nucleotides are ubiquitous signalling molecules which modulate distinct physiological and pathological processes. Nucleotide concentrations in the extracellular space are strictly regulated by cell surface enzymes, called ectonucleotidases, which hydrolyze nucleotides to the respective nucleosides. Recent studies suggest that ectonucleotidases play a significant role in inflammation by adjusting the balance between ATP, a widely distributed proinflammatory danger signal, and the anti-inflammatory mediator adenosine. There is increasing evidence for a central role of adenosine in alloantigen-mediated diseases such as solid organ graft rejection and acute graft-versus-host disease (GvHD). Solid organ and hematopoietic cell transplantation are established treatment modalities for a broad spectrum of benign and malignant diseases. Immunological complications based on the recognition of nonself-antigens between donor and recipient like transplant rejection and GvHD are still major challenges which limit the long-term success of transplantation. Studies in the past two decades indicate that purinergic signalling influences the severity of alloimmune responses. This paper focuses on the impact of ectonucleotidases, in particular, NTPDase1/CD39 and ecto-5'-nucleotidase/CD73, on allograft rejection, acute GvHD, and graft-versus-leukemia effect, and on possible clinical implications for the modulation of purinergic signalling after transplantation.
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11
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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: 775] [Impact Index Per Article: 64.6] [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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12
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Stanojević I, Drakulić D, Petrović S, Milošević M, Jovanović N, Horvat A. Kinetic characterization of ecto-nucleoside triphosphate diphosphohydrolases in brain nerve terminals during rat postnatal development. RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY A 2011. [DOI: 10.1134/s0036024411130292] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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13
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Papanikolaou A, Papafotika A, Christoforidis S. CD39 Reveals Novel Insights into the Role of Transmembrane Domains in Protein Processing, Apical Targeting and Activity. Traffic 2011; 12:1148-65. [DOI: 10.1111/j.1600-0854.2011.01224.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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14
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Acute restraint stress in zebrafish: behavioral parameters and purinergic signaling. Neurochem Res 2011; 36:1876-86. [PMID: 21603935 DOI: 10.1007/s11064-011-0509-z] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/12/2011] [Indexed: 12/20/2022]
Abstract
Despite the extensive knowledge about the effects of acute restraint stress (ARS) in rodents, zebrafish research is still elementary in this field, and the consequences of stress on purinergic system are unclear. Therefore, we evaluated the effects of ARS on behavior, biochemical, and molecular parameters in zebrafish brain. Animals were submitted to a 90 min ARS protocol and tested for anxiety levels, exploratory behavior, and memory performance. Furthermore, we analyzed ectonucleotidase and adenosine deaminase activities and their gene expression profile, as well as transcription of adenosine receptors. ARS increased anxiety, but did not impair locomotion or cognition. ARS significantly increased ATP hydrolysis, decreased cytosolic ADA activity, and changed the entpd and adora gene expression. In conclusion, ARS disturbed zebrafish behavior, and we hypothesize that the augmentation in adenosine-mediated signaling may be a strategy to reestablish homeostasis and normal behavior after a stressful event.
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15
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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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16
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Souza CGD, Böhmer AE, Müller AP, Oses JP, Viola GG, Lesczinski DN, Souza DGD, Knorr L, Moreira JD, Lhullier F, Souza DO, Perry MLS. Effects of a highly palatable diet on lipid and glucose parameters, nitric oxide, and ectonucleotidases activity. Appl Physiol Nutr Metab 2010; 35:591-7. [PMID: 20962914 DOI: 10.1139/h10-048] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Obesity has reached epidemic proportions worldwide and is stimulated by the ready availability of food rich in fat and sugar (highly palatable diet). This type of diet increases the risks of obesity-associated pathologies, such as insulin resistance and cardiovascular disease. Nitric oxide, a potent endogenous vasodilator, is decreased in these pathologies, mostly as a result of insulin resistance. Ectonucleotidases are ecto and soluble enzymes that regulate the availability of the nucleotides ATP, ADP, and AMP and the nucleoside adenosine in the vascular system, thereby affecting vasoconstriction, vasodilatation, and platelet aggregation homeostasis. The aim of this study was to evaluate the effects of a highly palatable diet on serum lipid and glucose parameters, nitric oxide, and ectonucleotidase activity. Forty male Wistar rats were fed 1 of 2 diets for either 45 days or 4 months: standard chow (SC, n = 10) or a highly palatable diet enriched with sucrose (HP, n = 10). Body mass, visceral fat mass, glucose tolerance, cholesterol (total, high-density lipoprotein (HDL) and non-HDL), serum triacylglycerol, liver triacylglycerol, and free glycerol were increased in the HP group after 45 days and after 4 months, whereas insulin levels were not different between the groups at either time. Furthermore, levels of nitric oxide metabolites and ATP, ADP, and AMP hydrolysis were significantly lower in the HP group (p < 0.05) after 4 months. In conclusion, the consumption of the HP diet for 4 months induced overall corporal and metabolic changes, and decreased nitric oxide metabolites and ectonucleotidase activity, thereby promoting an appropriate environment for the development of cardiovascular diseases, without apparent changes in insulin levels.
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Affiliation(s)
- Carolina Guerini de Souza
- Department of Biochemistry, Federal University of Rio Grande do Sul - UFRGS, Rua Ramiro Barcelos, 2600 anexo, CEP 90035003, Porto Alegre, RS, Brazil.
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17
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Rozisky JR, da Silva RS, Adachi LS, Capiotti KM, Ramos DB, Bogo MR, Bonan CD, Sarkis JJF, Torres ILDS. Neonatal morphine exposure alters E-NTPDase activity and gene expression pattern in spinal cord and cerebral cortex of rats. Eur J Pharmacol 2010; 642:72-6. [PMID: 20553911 DOI: 10.1016/j.ejphar.2010.05.044] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2010] [Revised: 04/25/2010] [Accepted: 05/23/2010] [Indexed: 12/25/2022]
Abstract
The neonate opioid system has been frequently investigated, and studies have shown that exposure to drugs in early life can have implications for nervous system development. It has been proposed that adenosine is involved in opioid antinociception, and ATP is involved in central and peripheral mechanisms of nociception. Extracellular nucleotides can be hydrolyzed by E-NTPDases and ecto-5'nucleotidase, which present the functions of removing ATP and generating adenosine. In this study, we evaluated ATP, ADP, and AMP hydrolysis in synaptosomes from spinal cord and cerebral cortex of rats at postnatal day 16 after repeated morphine exposure in early life (postnatal day 8 to 14). Additionally, we evaluated E-NTPDase (1, 2 and 3) and ecto-5'nucleotidase gene expression by semi-quantitative RT-PCR analysis. We observed an increase in ATP hydrolysis in the cerebral cortex, and a decrease in ADP hydrolysis in spinal cord. Expression levels of E-NTPDase 1 decreased in cerebral cortex and increased in spinal cord. Our findings highlight the importance of the purinergic system in young rats submitted to repeated morphine exposure by showing that in the neonatal period such exposure is capable of affecting the control system for nucleotide levels, which can promote changes in modulation or transmission of painful stimuli.
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Affiliation(s)
- Joanna Ripoll Rozisky
- Laboratório de Farmacologia da Dor e da Inflamação, Departamento de Farmacologia, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Rua Sarmento Leite, 500 sala 202, CEP 90050-170, Porto Alegre, Brazil
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18
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Vivian JP, Riedmaier P, Ge H, Le Nours J, Sansom FM, Wilce MCJ, Byres E, Dias M, Schmidberger JW, Cowan PJ, d'Apice AJF, Hartland EL, Rossjohn J, Beddoe T. Crystal structure of a Legionella pneumophila ecto -triphosphate diphosphohydrolase, a structural and functional homolog of the eukaryotic NTPDases. Structure 2010; 18:228-38. [PMID: 20159467 DOI: 10.1016/j.str.2009.11.014] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2009] [Revised: 11/16/2009] [Accepted: 11/24/2009] [Indexed: 12/20/2022]
Abstract
Many pathogenic bacteria have sophisticated mechanisms to interfere with the mammalian immune response. These include the disruption of host extracellular ATP levels that, in humans, is tightly regulated by the nucleoside triphosphate diphosphohydrolase family (NTPDases). NTPDases are found almost exclusively in eukaryotes, the notable exception being their presence in some pathogenic prokaryotes. To address the function of bacterial NTPDases, we describe the structures of an NTPDase from the pathogen Legionella pneumophila (Lpg1905/Lp1NTPDase) in its apo state and in complex with the ATP analog AMPPNP and the subtype-specific NTPDase inhibitor ARL 67156. Lp1NTPDase is structurally and catalytically related to eukaryotic NTPDases and the structure provides a basis for NTPDase-specific inhibition. Furthermore, we demonstrate that the activity of Lp1NTPDase correlates directly with intracellular replication of Legionella within macrophages. Collectively, these findings provide insight into the mechanism of this enzyme and highlight its role in host-pathogen interactions.
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Affiliation(s)
- Julian P Vivian
- The Protein Crystallography Unit, ARC Centre of Excellence in Structural and Functional Microbial Genomics, Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Clayton, Victoria 3800, Australia
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19
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Siebel AM, Rico EP, Capiotti KM, Piato AL, Cusinato CT, Franco TMA, Bogo MR, Bonan CD. In vitro effects of antiepileptic drugs on acetylcholinesterase and ectonucleotidase activities in zebrafish (Danio rerio) brain. Toxicol In Vitro 2010; 24:1279-84. [PMID: 20362660 DOI: 10.1016/j.tiv.2010.03.018] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2010] [Revised: 03/23/2010] [Accepted: 03/28/2010] [Indexed: 01/07/2023]
Abstract
Carbamazepine (CBZ), phenytoin (PHT), and gabapentine (GBP) are classical antiepileptic drugs (AEDs) that act through a variety of mechanisms. We have tested the in vitro effects of CBZ, PHT, and GBP at different concentrations on ectonucleotidase and acetylcholinesterase activities in zebrafish brain. CBZ inhibited ATP hydrolysis at 1000 microM (32%) whereas acetylcholine hydrolysis decreased at 500 microM (25.2%) and 1000 microM (38.7%). PHT increased AMP hydrolysis both at 500 microM (65%) and 1000 microM (64.8%). GBP did not promote any significant changes on ectonucleotidase and acetylcholinesterase activities. These results have shown that CBZ can reduce NTPDase (nucleoside triphosphate diphosphohydrolase) and PHT enhance ecto 5'-nucleotidase activities. Therefore, it is possible to suggest that the AEDs induced-effects on ectonucleotidases are related to enzyme anchorage form. Our findings have also shown that high CBZ concentrations inhibit acetylcholinesterase activity, which can induce an increase of acetylcholine levels. Taken together, these results showed a complex interaction among AEDs, purinergic, and cholinergic systems, providing a better understanding of the AEDs pharmacodynamics.
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Affiliation(s)
- A M Siebel
- Laboratório de Neuroquímica e Psicofarmacologia, Departamento de Biologia Celular e Molecular, Programa de Pós-Graduação em Biologia Celular e Molecular, Faculdade de Biociências, Pontifícia Universidade Católica do Rio Grande do Sul. Avenida Ipiranga, 6681, 90619-900 Porto Alegre, RS, Brazil
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20
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Gaddie KJ, Kirley TL. Proline residues link the active site to transmembrane domain movements in human nucleoside triphosphate diphosphohydrolase 3 (NTPDase3). Purinergic Signal 2010; 6:327-37. [PMID: 21103216 DOI: 10.1007/s11302-010-9180-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2009] [Accepted: 03/01/2010] [Indexed: 10/19/2022] Open
Abstract
The active sites of the membrane-bound nucleoside triphosphate diphosphohydrolases (NTPDases) regulate and are regulated by coordinated and spatially distant movements of their transmembrane helices, modulating enzyme activity, and substrate specificity. Using site-directed mutagenesis, the roles of the conserved proline residues (N-terminal: P52 and P53; C-terminal: P472, P476, P481, P484, and P485) of human NTPDase3, located in the "linker regions" that connect the N- and C-terminal transmembrane helices with the extracellular active site, were examined. Single cysteine substitutions were strategically placed in the transmembrane domain (N-terminal helix: V42C; C-terminal helix: G489C) to serve as cross-linking "sensors" of helical interactions. These "sensor" background mutant proteins (V42C and G489C NTPDase3) are enzymatically active and are cross-linked by copper phenanthroline less efficiently in the presence of adenosine triphosphate (ATP). Proline to alanine substitutions at P53, P481, P484, and P485 in the V42C background, as well as P53, P481, and P484 in the G489C background, exhibited decreased nucleotidase activities. More importantly, alanine substitutions at P53 and P481 in the V42C background and P481 in the G489C background no longer exhibited the ATP-induced decrease in transmembrane cross-linking efficiency. Interestingly, the P485A mutation abolished oxidative cross-linking at G489C both in the presence and absence of ATP. Taken together, these results suggest a role for proline residues 53 and 481 in the linker regions of human NTPDase3 for coupling nucleotide binding at the enzyme active site to movements and/or rearrangements of the transmembrane helices necessary for optimal nucleotide hydrolysis.
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Affiliation(s)
- Keith J Gaddie
- Department of Pharmacology and Cell Biophysics, College of Medicine, University of Cincinnati, P.O. Box 670575, Cincinnati, OH 45267-0575 USA
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21
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Li CS, Lee Y, Knowles AF. The stability of chicken nucleoside triphosphate diphosphohydrolase 8 requires both of its transmembrane domains. Biochemistry 2010; 49:134-46. [PMID: 20000380 DOI: 10.1021/bi901820c] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Chicken nucleoside triphosphate diphosphohydrolase 8 (NTPDase8) is a cell surface ectonucleotidase with a large extracellular domain (ECD) containing the active site and is anchored to the membrane by two transmembrane domains (TMDs) at the N- and C-termini. Unlike other cell surface NTPDases that have been characterized, the chicken NTPDase8 is not susceptible to substrate inactivation or agents that cause membrane perturbation. To determine if the stability of the enzyme is inherent in its ECD, the cDNA construct of the soluble chicken NTPDase8 was expressed and the protein purified. The ATPase activity of the purified soluble chicken NTPDase8 was less than 15% of that of the purified full-length enzyme. Strikingly, in contrast to the membrane-bound enzyme, the activity of the soluble chicken NTPDase8 decreased with time in a temperature-dependent manner as a result of inactivation by ATP, ADP, and P(i). Truncated mutants in which the ECD is anchored by a single TMD at either the N- or the C-terminus by the native chicken NTPDase TMDs or a TMD from a different NTPDase, human NTPDase2, also displayed a nonlinear time course of ATP hydrolysis. While removal of the N- or C-terminal TMD affected protein expression differently, the truncated mutants were generally similar to the soluble chicken NTPDase8 with respect to ATP, ADP, and P(i) inactivation. Other biochemical characteristics, e.g., ATPase/ADPase ratios, inhibition by azide, and affinity for ATP, were also altered when one or both of the TMDs were removed from the chicken NTPDase8. These results indicate that (1) both TMDs of the chicken NTPDase8 are required to maintain stability of the enzyme and maximal catalytic activity and (2) the conformations of the ectodomain in the soluble enzyme and the truncated mutants differ from that of the full-length chicken NTPDase8.
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Affiliation(s)
- Cheryl S Li
- Department of Chemistry and Biochemistry, San Diego State University, San Diego, California 92182-1030, USA
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22
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Grosso S, Rocchi R, Margollicci M, Vatti G, Luddi A, Marchi F, Balestri P. Postictal serum nucleotidases activities in patients with epilepsy. Epilepsy Res 2009; 84:15-20. [PMID: 19157784 DOI: 10.1016/j.eplepsyres.2008.11.020] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2008] [Revised: 11/21/2008] [Accepted: 11/30/2008] [Indexed: 12/20/2022]
Abstract
Adenosine, a potent anticonvulsant, can be produced in the body by the hydrolysis of adenine nucleotides through the action of ecto- or soluble nucleotidases. Changes in nucleotide hydrolysis occur after pentylenetetrazol-induced epileptic events. We evaluated serum ATP, ADP and AMP hydrolysis rates and soluble nucleotide phosphodiesterase (PDEase) activity at 5, 10, 15, 30 and 60 min, and 12h following an epileptic event. Fifteen patients (seven female, eight male; mean age 15.5 years) were included in the study. The type of seizure was generalized in four patients and was localization related in the remaining 11. There were no differences in adenine nucleotide hydrolysis rates between patients and healthy subjects in the interictal stage. In comparison with controls, ATP, ADP and AMP hydrolysis rates were significantly increased at 5 min (53+/-1.4%, 79.2+/-2.8% and 37.0+/-2.6%, respectively) and up to 30 min following the epileptic event. In contrast to ADP and AMP, ATP hydrolysis remained significantly increased at 60 min (71.4+/-1.6%), returning to the basal level after 12h. Serum PDEase activity was also significantly higher in the patients than in healthy subjects, peaking at 15 min (61+/-2.9%) and remaining significantly increased up to 60 min (4.6+/-1.2%) following the epileptic episode. Globally, the variations in the postictal serum ADP hydrolysis rate almost overlapped those of AMP hydrolysis, whereas changes in the ATP hydrolysis rate overlapped those of PDEase activity. The clinical significance of this elevation in postictal soluble serum nucleotidase activity remains to be clarified. However, it is possible to hypothesize that the higher nucleotidase activity might play a role in the modulation of epileptic events.
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Affiliation(s)
- Salvatore Grosso
- Department of Pediatrics, Pediatric Neurology Section, University of Siena, Siena, Italy.
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23
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Structural insight into signal conversion and inactivation by NTPDase2 in purinergic signaling. Proc Natl Acad Sci U S A 2008; 105:6882-7. [PMID: 18458329 DOI: 10.1073/pnas.0802535105] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Cell surface-located nucleoside triphosphate diphosphohydrolases (NTPDase1, -2, -3, and -8) are oligomeric integral membrane proteins responsible for signal conversion and inactivation in extracellular nucleotide-mediated "purinergic" signaling. They catalyze the sequential hydrolysis of the signaling molecule ATP via ADP to AMP. Here we present the structure of the extracellular domain of Rattus norvegicus NTPDase2 in an active state at resolutions between 1.7 A and 2.1 A in four different forms: (i) apo form, (ii) ternary complex with the nonhydrolyzable ATP analog AMPPNP and cofactor Ca(2+), (iii) quaternary complex with Ca(2+) and bound products AMP and phosphate, and (iv) binary product complex with AMP only. Analysis of the ATP (analog) binding mode explains the importance of several residues for activity and allows suggestion of a catalytic mechanism. The carboxylate group of E165 serves as a catalytic base and activates a water molecule, which is well positioned for nucleophilic attack on the terminal phosphate. Based on analysis of the two product complex structures in which AMP adopts different conformations, a substrate binding mode for ADP hydrolysis is proposed. This allows for an understanding of how the same hydrolytic site can be engaged in ATP and ADP but not AMP hydrolysis.
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24
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Pedrazza EL, Senger MR, Rico EP, Zimmermann FF, Pedrazza L, de Freitas Sarkis JJ, Bonan CD. Fluoxetine and nortriptyline affect NTPDase and 5′-nucleotidase activities in rat blood serum. Life Sci 2007; 81:1205-10. [PMID: 17889906 DOI: 10.1016/j.lfs.2007.08.020] [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] [Received: 04/27/2007] [Revised: 08/01/2007] [Accepted: 08/20/2007] [Indexed: 10/22/2022]
Abstract
Depression is a serious condition associated with considerable morbidity and mortality. Selective serotonin reuptake inhibitors and tricyclic antidepressants, such as fluoxetine and nortriptyline, respectively, were commonly used in treatment for depression. Selective serotonin reuptake inhibitors have been associated with increased risk of bleeding complications, possibly as a result of inhibition of platelet aggregation. ATP, ADP and adenosine are signaling molecules in the vascular system and nucleotidases activities are considered an important thromboregulatory system which functions in the maintenance of blood fluidity. Therefore, here we investigate the effect of in vivo (acute and chronic) and in vitro treatments with the antidepressant drugs on nucleotidases activities in rat blood serum. In acute treatment, nortriptyline decreased ATP hydrolysis (41%), but not altered ADP and AMP hydrolysis. In contrast, fluoxetine did not alter NTPDase and ecto-5'-nucleotidase activities. A significant inhibition of ATP, ADP, and AMP hydrolysis were observed in chronic treatment with fluoxetine (60%, 32%, and 42% for ATP, ADP, and AMP hydrolysis, respectively). Similar effects were shown in chronic treatment with nortriptyline (37%, 41%, and 30% for ATP, ADP, and AMP hydrolysis, respectively). In addition, there were no significant changes in NTPDase and ecto-5'-nucleotidase activities when fluoxetine and nortriptyline (100, 250, and 500 microM) were tested in vitro. Our results have shown that fluoxetine and nortriptyline changed the nucleotide catabolism, suggesting that homeostasis of vascular system can be altered by antidepressant treatments.
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Affiliation(s)
- Eduardo Luiz Pedrazza
- Laboratório de Neuroquímica e Psicofarmacologia, Departamento de Biologia Celular e Molecular, Faculdade de Biociências, Pontifícia Universidade Católica do Rio Grande do Sul. Avenida Ipiranga, 6681, 90619-900, Porto Alegre, RS, Brazil
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25
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Leal CAM, Schetinger MRC, Leal DBR, Bauchspiess K, Schrekker CML, Maldonado PA, Morsch VM, da Silva JEP. NTPDase and 5'-nucleotidase activities in platelets of human pregnants with a normal or high risk for thrombosis. Mol Cell Biochem 2007; 304:325-30. [PMID: 17557193 DOI: 10.1007/s11010-007-9515-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2007] [Accepted: 05/16/2007] [Indexed: 10/23/2022]
Abstract
The nucleotide degrading enzymes, ectonucleotidases, present on the platelet surface of human pregnant with a normal (without complications) or high risk for thrombosis (hypertension and gestational diabetes) were studied. NTPDase (E.C. 3.6.1.5, CD39) and 5'-nucleotidase (E.C. 3.1.3.5, CD73) activities of four patient groups, non-pregnant (NP, n = 18), pregnant without complications (P, n = 25), pregnant with hypertension (HP, n = 15) and pregnant with gestational diabetes mellitus (GDP, n = 10), were analyzed. Increased NTPDase activities were observed in the groups P (37.0%, S.D. = 2.03 and 34.0%, S.D. = 3.19), HP (40.0%, S.D. = 3.32 and 56.0%, S.D. = 3.25) and GDP (23.0%, S.D. = 2.30 and 42.0%, S.D. = 2.26) in comparison to the control group NP (p < 0.01, S.D. = 1.92 and S.D. = 2.48) when ATP and ADP were used as substrate, respectively. AMP was used as substrate to determine the 5'-nucleotidase activities, which showed to be elevated in the groups P (45.0%, S.D. = 1.73), HP (54.0%, S.D. = 2.64) and GDP (68.0%, S.D. = 1.69) when compared to the control group NP (p < 0.01, S.D. = 1.26). However, no statistically significant differences were observed between the groups P, HP and GDP. As a consequence, the enhanced ATP, ADP and AMP hydrolysis was ascribed to the pregnancy itself, independent of a normal or high risk for thrombosis. The enhanced NTPDase and 5'-nucleotidase activities in platelets suggest that these enzymes are involved in the thromboregulation process in the pregnancy.
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Affiliation(s)
- Claudio A M Leal
- Departamento de Análises Clínicas e Toxicológicas, Centro de Ciências da Saúde, Universidade Federal de Santa Maria, Av. Roraima, Santa Maria, RS 97105-900, Brazil
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26
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Delwing D, Delwing D, Gonçalves MCF, Sarkis JJF, Wyse ATS. NTPDase and 5'-nucleotidase activities of synaptosomes from hippocampus of rats subjected to hyperargininemia. Neurochem Res 2007; 32:1209-16. [PMID: 17401661 DOI: 10.1007/s11064-007-9292-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2006] [Accepted: 01/19/2007] [Indexed: 10/23/2022]
Abstract
ATP is an important excitatory neurotransmitter and adenosine acts as a neuromodulatory structure inhibiting neurotransmitters release in the central nervous system. Since the ecto-nucleotidase cascade that hydrolyzes ATP to adenosine is involved in the control of brain functions and previous studies realized in our laboratory have recently reported that acute administration of Arg decreases the NTPDase and 5'-nucleotidase activities of rat blood serum, in the present study we investigated the effect of arginine administration on NTPDase and 5'-nucleotidase activities by synaptosomes from hippocampus of rats. First, sixty-days-old rats were treated with a single or a triple intraperitoneal injection of arginine (0.8 g/Kg) or an equivalent volume of 0.9% saline solution (control) and were killed 1 h later. Second, rats received an intracerebroventricular injection of 1.5 mM arginine solution or saline (5 microL) and were killed 1 h later. We also tested the in vitro effect of arginine (0.1-1.5 mM) on nucleotide hydrolysis in synaptosomes from rat hippocampus. Results showed that intraperitoneal arginine administration did not alter nucleotide hydrolysis. On the other hand, arginine administered intracerebroventricularly reduced ATP (32%), ADP (30%) and AMP (21%) hydrolysis, respectively. In addition, arginine added to the incubation medium, provoked a decrease on ATP (19%), ADP (17%) and AMP (23%) hydrolysis, respectively. Furthermore, kinetic studies showed that the inhibitory effect of arginine was uncompetitive in relation to ATP, ADP and AMP. In conclusion, according to our results it seems reasonable to postulate that arginine alters the cascade involved in the extracellular degradation of ATP to adenosine.
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Affiliation(s)
- Débora Delwing
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-Anexo, CEP 90035-003, Porto Alegre, RS, Brazil
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27
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Grinthal A, Guidotti G. Bilayer mechanical properties regulate the transmembrane helix mobility and enzymatic state of CD39. Biochemistry 2007; 46:279-90. [PMID: 17198399 PMCID: PMC2536646 DOI: 10.1021/bi061052p] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
CD39 can exist in at least two distinct functional states depending on the presence and intact membrane integration of its two transmembrane helices. In native membranes, the transmembrane helices undergo dynamic rotational motions that are required for enzymatic activity and are regulated by substrate binding. In this study, we show that bilayer mechanical properties regulate conversion between the two enzymatic functional states by modulating transmembrane helix dynamics. Alteration of membrane properties by insertion of cone-shaped or inverse cone-shaped amphiphiles or by cholesterol removal switches CD39 to the same enzymatic state that removal or solubilization of the transmembrane domains does. The same membrane alterations increase the propensity of both transmembrane helices to rotate within the packed structure, resulting in a structure with greater mobility but not an altered primary conformation. Membrane alteration also abolishes the ability of the substrate to stabilize the helices in their primary conformation, indicating a loss of coupling between substrate binding and transmembrane helix dynamics. Removal of either transmembrane helix mimics the effect of membrane alteration on the mobility and substrate sensitivity of the remaining helix, suggesting that the ends of the extracellular domain have intrinsic flexibility. We suggest that a mechanical bilayer property, potentially elasticity, regulates CD39 by altering the balance between the stability and flexibility of its transmembrane helices and, in turn, of its active site.
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Affiliation(s)
- Alison Grinthal
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts 02138, USA.
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28
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CD39, NTPDase 1, is attached to the plasma membrane by two transmembrane domains. Why? Purinergic Signal 2006; 2:391-8. [PMID: 18404478 PMCID: PMC2254477 DOI: 10.1007/s11302-005-5907-8] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2005] [Revised: 12/14/2005] [Accepted: 12/14/2005] [Indexed: 11/20/2022] Open
Abstract
Since the identification of CD39 and other members of the e-NTPDase (ecto-nucleoside triphosphate diphosphohydrolase) family as the primary enzymes responsible for cell surface nucleotide hydrolysis, one of their most intriguing features has been their unusual topology. The active site lies in the large extracellular region, but instead of being anchored in the membrane by a single transmembrane domain or lipid link like other ectoenzymes, CD39 has two transmembrane domains, one at each end. In this review we discuss evidence that the structure and dynamics of the transmembrane helices are intricately connected to enzymatic function. Removal of either or both transmembrane domains or disruption of their native state by detergent solubilization reduces activity by 90%, indicating that native function requires both transmembrane domains to be present and in the membrane. Enzymatic and mutational analysis of the native and truncated forms has shown that the active site can exist in distinct functional states characterized by different total activities, substrate specificities, hydrolysis mechanisms, and intermediate ADP release during ATP hydrolysis, depending on the state of the transmembrane domains. Disulfide crosslinking of cysteines introduced within the transmembrane helices revealed that they interact within and between molecules, in particular near the extracellular domain, and that activity depends on their organization. Both helices exhibit a high degree of rotational mobility, and the ability to undergo dynamic motions is required for activity and regulated by substrate binding. Recent reports suggest that membrane composition can regulate NTPDase activity. We propose that mechanical bilayer properties, potentially elasticity, might regulate CD39 by altering the balance between stability and mobility of its transmembrane domains.
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29
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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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30
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Böhmer AE, Pochmann D, Sarkis JJF. In vitro effect of homocysteine on nucleotide hydrolysis by blood serum from adult rats. Chem Biol Interact 2006; 160:159-64. [PMID: 16466706 DOI: 10.1016/j.cbi.2006.01.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2005] [Revised: 01/03/2006] [Accepted: 01/11/2006] [Indexed: 11/21/2022]
Abstract
During the past few years, elevated blood levels of homocysteine (Hcy) have been linked to increased risk of premature coronary artery disease, stroke and thromboembolism. These processes can be also related to the ratio adenine nucleotide/adenosine, since extracellularly these nucleotides are associated with modulation of processes such as platelet aggregation, vasodilatation and coronary flow. Furthermore, there are some studies that suggest a relationship between Hcy and plasma adenosine concentrations. The sequential hydrolysis of ATP to adenosine by soluble nucleotidases constitutes one of the systems for rapid inactivation of circulating adenine nucleotides. Thus, the main objective of this study was to evaluate if Hcy can participate in the modulation of the extracellular adenine nucleotide hydrolysis by rat blood serum. Our results showed that Hcy, at final concentrations of 5.0 mM, inhibits in vitro ATP, ADP and AMP hydrolysis by 26, 21 and 16%, respectively. Also Hcy, at final concentrations of 8.0mM, inhibited the in vitro hydrolysis of ATP, ADP and AMP by 46, 44 and 44%, respectively. Kinetic analysis showed that the inhibitions of the three adenine nucleotide hydrolyses in the presence of Hcy, by serum of adult rats, is of the uncompetitive type. The IC50 calculated from the results obtained were 6.52+/-1.75 mM (n = 4), 5.18 +/- 0.64 mM (n = 3) and 5.16 +/- 1.22 mM (n = 3) for ATP, ADP and AMP hydrolysis, respectively.
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Affiliation(s)
- Ana Elisa Böhmer
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-Anexo, CEP 90035-003, Porto Alegre, RS, Brazil
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31
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Glenn JR, White AE, Johnson A, Fox SC, Behan MWH, Dolan G, Heptinstall S. Leukocyte count and leukocyte ecto-nucleotidase are major determinants of the effects of adenosine triphosphate and adenosine diphosphate on platelet aggregation in human blood. Platelets 2005; 16:159-70. [PMID: 16011960 DOI: 10.1080/09537100500063889] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
ADP induces platelet aggregation in human whole blood and platelet-rich plasma (PRP). ATP induces aggregation in whole blood only; this involves leukocytes and is mediated by ADP. Here we studied ATP- and ADP-induced aggregation in patients with raised leukocyte counts (mean 46.2x10(3) leukocytes/microl). Platelet aggregation was measured by platelet counting. ATP, ADP and metabolites were measured by HPLC. Aggregation to ADP (1-10 microM) and ATP (10-100 microM) was markedly reduced, but to ATP (1000 microM) was enhanced (all p<0.001). Aggregation to ADP in PRP was normal. Increasing the leukocyte count in normal blood reproduced the findings in the patients. Adding leukocytes (either MNLs or PMNLs) to normal PRP enabled a response to ATP and caused marked inhibition of ADP-induced aggregation. Breakdown of ATP or ADP to AMP and adenosine in leukocyte-rich plasma was rapid (t1/2=4 min) and far higher than in cell-free plasma or PRP. With ATP there was also formation of ADP, maximal at 4 min. The presence of the ectonucleotidase NTPDase1 (CD39) was demonstrated on MNLs (all of the monocytes and a proportion of the lymphocytes) and all PMNLs by flow cytometry. We conclude that leukocytes provide a means of dephosphorylating ATP which enables ATP-induced aggregation via conversion to ADP, but also convert ADP to AMP and adenosine. Platelet aggregation extent is a balance between these activities, and high white cell counts influence this balance.
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Affiliation(s)
- Jacqueline R Glenn
- Centre for Integrated Systems Biology and Medecine, Institute of Clinical Research, University of Nottingham, Nottingham, UK
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32
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Bruno AN, Fontella FU, Crema LM, Bonan CD, Dalmaz C, Barreto-Chaves MLM, Sarkis JJF. Hyperthyroidism changes nociceptive response and ecto-nucleotidase activities in synaptosomes from spinal cord of rats in different phases of development. Comp Biochem Physiol A Mol Integr Physiol 2005; 140:111-6. [PMID: 15664319 DOI: 10.1016/j.cbpb.2004.11.007] [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: 09/19/2004] [Revised: 11/05/2004] [Accepted: 11/08/2004] [Indexed: 11/20/2022]
Abstract
Changes in transport, receptors and production of extracellular adenosine have been observed after induction of hyperthyroidism. Adenosine is associated with inhibitory actions such as reduction in release of excitatory neurotransmitters and antinociception at spinal site. In contrast, ATP acts as an excitatory neurotransmitter and produces pronociceptive actions. ATP may be completely hydrolyzed to adenosine by an enzyme chain constituted by an ATP diphosphohydrolase and an ecto-5'-nucleotidase, as previously described in the spinal cord. Thus, we now investigated the effects of the hyperthyroidism on adenine nucleotide hydrolysis in the spinal cord and verified the nociceptive response in this pathology during different phases of development. Hyperthyroidism was induced in male Wistar rats, aged 5, 60 and 330 days by daily intraperitoneal injections of L-thyroxine (T4) for 14 days. Nociception was assessed with a tail-flick apparatus. Rats starting the treatment aged 5 days demonstrated a significant increase in ADP and AMP hydrolysis and increased tail-flick latency (TFL). In contrast, in the spinal cord from hyperthyroid rats aged 60 and 330 days old, the hydrolysis of ATP, ADP and AMP were significantly decreased. Accordingly, the tail-flick latency was decreased, indicating a hyperalgesic response. These results suggest the involvement of ecto-nucleotidases in the control of the hyperthyroidism-induced nociceptive response in rats at distinct developmental stages.
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Affiliation(s)
- Alessandra Nejar Bruno
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Avenida Ramiro Barcellos 2600-ANEXO, 90035-003, Porto Alegre, RS, Brazil
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33
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Kapojos JJ, van den Berg A, Borghuis T, Banas B, Huitema S, Poelstra K, Bakker WW. Enhanced ecto-apyrase activity of stimulated endothelial or mesangial cells is downregulated by glucocorticoids in vitro. Eur J Pharmacol 2005; 501:191-8. [PMID: 15464078 DOI: 10.1016/j.ejphar.2004.08.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2004] [Revised: 08/02/2004] [Accepted: 08/04/2004] [Indexed: 10/26/2022]
Abstract
Endothelial as well as mesangial cells show enhanced activity of ecto-apyrase following pro-inflammatory stimulation in vitro. Since this ecto-enzyme appears to be able to regulate plasma hemopexin, which latter molecule plays a role in the pathogenesis of corticosteroid responsive nephrotic syndrome, the question was raised whether glucocorticoids are potentially able to downregulate ecto-apyrase activity of these cells. Therefore, cell cultures of endothelial or mesangial were stimulated with or without lipopolysaccharide (10 ng/ml). Parallel cultures were supplemented with prednisolone with or without the glucocorticoid receptor antagonist mifepristone in various concentrations. After 24 h, cytospins were prepared and cytochemically stained for ecto-apyrase activity. mRNA for apyrase of these cells was detected using reverse transcription-polymerase chain reaction (RT-PCR). Apyrase activity of either cells or soluble apyrase (0.16 U/ml buffer) with or without supplementation of prednisolone were biochemically assayed for their phosphatase activity. The results show significantly decreased ecto-apyrase activity of lipopolysaccharide-stimulated cells after treatment with prednisolone as compared to non-prednisolone-treated cells. Preincubation with mifepristone did not inhibit the effect of prednisolone. Identical mRNA signals for apyrase were found in prednisolone and non-prednisolone-treated cells. Interestingly, soluble apyrase also showed a significant decrease of activity following preincubation with prednisolone. It is concluded that prednisolone is able to downregulate ecto-apyrase of stimulated endothelial or mesangial cells, which may potentially inhibit the conversion of hemopexin to its pro-inflammatory isoform. As blocking of the cytosolic glucocorticoid receptor showed no effect upon the prednisolone action, whereas prednisolone is able to affect soluble apyrase per se, it is felt that this particular action of prednisolone may (at least partly) be mediated through a non-genomic pathway.
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Affiliation(s)
- Jola J Kapojos
- Department of Pathology and Laboratory Medicine, University Hospital Groningen, PO Box 30.001, 9700 RB Groningen, The Netherlands
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Fontella FU, Bruno AN, Crema LM, Battastini AMO, Sarkis JJF, Netto CA, Dalmaz C. Acute and chronic stress alter ecto-nucleotidase activities in synaptosomes from the rat hippocampus. Pharmacol Biochem Behav 2005; 78:341-7. [PMID: 15219776 DOI: 10.1016/j.pbb.2004.04.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2004] [Revised: 04/05/2004] [Accepted: 04/08/2004] [Indexed: 10/26/2022]
Abstract
Hyperactivity of the stress response has long been recognized as maladaptive. The hippocampus, a brain structure important in mediating this response, is known to be affected by chronic stress, a situation reported to induce changes in adenine nucleotide hydrolysis in the rat. The enzymes catalyzing the hydrolysis of ATP to adenosine in the synaptic cleft are thought to have a role in modulating and controlling synaptic transmission. This study aimed to investigate the effect of acute and repeated restraint stress on the ATP, ADP and AMP hydrolyses in rat hippocampal synaptosomes. Adult male Wistar rats were submitted to acute or repeated (15 and 40 days) stress, and ATPase-ADPase, and 5'nucleotidase activities were assayed in the hippocampal synaptosomal fraction. Acute stress induced increased hydrolyses of ATP (21%), ADP (21%) and AMP (40%). In contrast, ATP hydrolysis was increased by 20% in repeatedly stressed rats, without changes in the ADP or AMP hydrolysis. The same results were observed after 15 or 40 days of stress. Therefore, acute stress increases ATP diphosphohydrolase activity which, in association with 5'-nucleotidase, contributes to the elimination of ATP and provides extracellular adenosine. Interestingly, increased ecto-ATPase activity in response to chronic stress reveals an adaptation to this treatment.
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Affiliation(s)
- Fernanda Urruth Fontella
- Departamento de Bioquímica, ICBS, Universidade Federal do Rio Grande do Sul, Rua Domingos Crescêncio, 215/101 90650-090- Porto Alegre, RS, Brazil.
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35
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Dai J, Liu J, Deng Y, Smith TM, Lu M. Structure and protein design of a human platelet function inhibitor. Cell 2004; 116:649-59. [PMID: 15006348 DOI: 10.1016/s0092-8674(04)00172-2] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2003] [Revised: 01/08/2004] [Accepted: 01/20/2004] [Indexed: 10/26/2022]
Abstract
Hematophagous arthropods secrete a salivary apyrase that inhibits platelet activation by catabolizing ADP released from damaged tissues and blood cells. We report the X-ray crystal structures of a human enzyme of the soluble apyrase family in its apo state and bound to a substrate analog. The structures reveal a nucleotide binding domain comprising a five-blade beta propeller, binding determinants of the substrate and the active site, and an unusual calcium binding site with a potential regulatory function. Using a comparative structural biology approach, we were able to redesign the human apyrase so as to enhance its ADPase activity by more than 100-fold. The engineered enzyme is a potent inhibitor of platelet aggregation and may serve as the basis for the development of a new class of antithrombotic agents.
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Affiliation(s)
- Jiayin Dai
- Department of Biochemistry, Weill Medical College of Cornell University, New York, NY 10021, USA
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36
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Torres ILS, Battastini AMO, Buffon A, Fürstenau CR, Siqueira I, Sarkis JJF, Dalmaz C, Ferreira MBC. Ecto-nucleotidase activities in spinal cord of rats changes as function of age. Int J Dev Neurosci 2004; 21:425-9. [PMID: 14659993 DOI: 10.1016/j.ijdevneu.2003.10.001] [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] [Indexed: 10/26/2022] Open
Abstract
An increase in ADP hydrolysis was observed in spinal cord synaptosomal fractions of 2-month-old Wistar male rats, when compared to other ages (1, 4 and 6 months of age), while no change in ATPase activity was observed. Conversely, in female rats, whilst no change in ADPase activity was observed in the spinal cord synaptosomal fraction, ATPase activity diminished with age, in 1-6-month-old animals. 5'-Nucleotidase activity was higher in the 4-month-old male and female rats in relation to 1 and 2-month-old animals. In the female rats, this activity continued to increase at least until 6 months of age. In conclusion, adenine nucleotides hydrolysis in synaptosomes from rat spinal cord is influenced by age and by gender. Since both ATP and adenosine may act as neuromodulators in the spinal cord, influencing several processes such as nociception, the regulation of ATP-metabolizing enzymes in spinal cord is probably important for the normal function of this tissue at different ages.
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Affiliation(s)
- Iraci Lucena S Torres
- Departamento de Bioqui;mica, ICBS, UFRGS, Rua Ramiro Barcelos 2600, Anexo, 90035-003, RS, Porto Alegre, Brazil
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37
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da Silva Torres IL, Bonan CD, Crema L, De Leon Nunes M, Battastini AMO, Sarkis JJF, Dalmaz C, Ferreira MBC. Effect of drugs active at adenosine receptors upon chronic stress-induced hyperalgesia in rats. Eur J Pharmacol 2003; 481:197-201. [PMID: 14642786 DOI: 10.1016/j.ejphar.2003.09.045] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Hyperalgesia and altered activities of enzymes involved in nucleotide hydrolysis are observed after exposure to repeated restraint in rats. Here, we investigated the effect of an adenosine A(1) receptor agonist, N(6)-cyclopentyladenosine (CPA, 3.35 mg/kg, i.p.), adenosine A(1) receptor antagonist, 1,3-dipropyl-8-cyclopentylxanthine (DPCPX, 0.8 mg/kg, i.p.) as well the effect of an adenosine reuptake blocker, dipyridamole (5 mg/kg, i.p.), on nociception in chronically stressed and control rats. We repeatedly submitted rats to restraint for 40 days. Nociception was assessed with a tail-flick apparatus. The control group presented increased tail-flick latencies after administration of CPA and dipyridamole, but this effect was not observed in the stressed group. DPCPX by itself had no effect on nociception. The analgesic effect of CPA and dipyridamole observed in the control group was reverted by DPCPX. These results indicate the involvement of adenosine A(1) receptor in the antinociception observed in control animals and suggest that the pain signaling induced by chronic stress presents a different modulation involving the adenosinergic system.
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Affiliation(s)
- Iraci Lucena da Silva Torres
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
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38
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Sørensen CE, Amstrup J, Rasmussen HN, Ankorina-Stark I, Novak I. Rat pancreas secretes particulate ecto-nucleotidase CD39. J Physiol 2003; 551:881-92. [PMID: 12832497 PMCID: PMC2343304 DOI: 10.1113/jphysiol.2003.049411] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Revised: 06/17/2003] [Accepted: 06/26/2003] [Indexed: 11/08/2022] Open
Abstract
In exocrine pancreas, acini release ATP and the excurrent ducts express several types of purinergic P2 receptors. Thereby, ATP, or its hydrolytic products, might play a role as a paracrine regulator between acini and ducts. The aim of the present study was to elucidate whether this acinar-ductal signalling is regulated by nucleotidase(s), and to characterize and localize one of the nucleotidases within the rat pancreas. Using RT-PCR and Western blotting we show that pancreas expresses the full length ecto-nucleoside triphosphate diphosphohydrolase, CD39. Immunofluorescence shows CD39 localization on basolateral membranes of acini and intracellularly. In small intercalated/ interlobular ducts, CD39 immunofluorescence was localized on the luminal membranes, while in larger ducts it was localized on the basolateral membranes. Upon stimulation with cholecystokinin-octapeptide-8 (CCK-8), acinar CD39 relocalizes in clusters towards the lumen and is secreted. As a result, pancreatic juice collected from intact pancreas stimulated with CCK-8 contained nucleotidase activity, including that of CD39, and no detectable amounts of ATP. Anti-CD39 antibodies detected the full length (78 kDa) CD39 in pancreatic juice. This CD39 was confined only to the particulate and not to the soluble fraction of CCK-8-stimulated secretion. No CD39 activity was detected in secretion stimulated by secretin. The role of secreted particulate, possibly microsomal, CD39 would be to regulate intraluminal ATP concentrations within the ductal tree. In conclusion, we show a novel inducible release of full length particulate CD39, and propose its role in the physiological context of pancreatic secretion.
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Affiliation(s)
- Christiane E Sørensen
- August Krogh Institute, University of Copenhagen, Universitetsparken 13, DK-2100 Copenhagen Ø, Denmark
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39
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Failer BU, Aschrafi A, Schmalzing G, Zimmermann H. Determination of native oligomeric state and substrate specificity of rat NTPDase1 and NTPDase2 after heterologous expression in Xenopus oocytes. EUROPEAN JOURNAL OF BIOCHEMISTRY 2003; 270:1802-9. [PMID: 12694193 DOI: 10.1046/j.1432-1033.2003.03542.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
NTPDase1 and NTPDase2 are two related plasma membrane-located enzymes involved in the extracellular degradation of nucleoside 5'-tri- and -diphosphates. They differ regarding their hydrolysis ratios for ATP and ADP. Both enzymes have a predicted transmembrane domain close to the N- and C-terminus, respectively, connected by an extensive extracellular domain that carries the active site. We expressed the rat-derived enzymes in Xenopus laevis oocytes and analyzed their quarternary structure. As revealed by application of blue native PAGE and a comparison of glutaraldehyde cross-linking, native NTPDase1 and NTPDase2 occur in oligomeric form. Oligomer formation of the cell surface-located pool of the enzymes was verified by surface iodination. The two enzymes differed in oligomeric structure and in oligomer complex stability. NTPDase1 preferentially occurred as a dimer that could be dissociated into monomeric forms in the presence of Coomassie Brilliant blue G-250 and dithiothreitol whereas NTPDase2 revealed higher oligomeric forms up to tetramers, largely resistant to dithiothreitol. Our results further suggest that the enzymes exist in varying oligomeric states. In contrast to NTPDase1, substrate specificity of NTPDase2 was altered with prolonged expression time, resulting in a decrease in the ATPase/ADPase activity ratio from 10 : 1 to 2.5 : 1. This was accompanied by a transition into a higher oligomeric state. Our results suggest that despite close sequence identity, NTPDase1 and NTPDase2 differ in oligomeric structure. Dynamic alterations in oligomeric state may induce changes in substrate preference and thus influence the pattern of extracellular nucleotide degradation in situ.
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Affiliation(s)
- Bernd U Failer
- AK Neurochemie, Biozentrum der J.W.Goethe-Universität, Frankfurt am Main, Germany
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40
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Abraham EH, Salikhova AY, Rapaport E. ATP in the Treatment of Advanced Cancer. CURRENT TOPICS IN MEMBRANES 2003. [DOI: 10.1016/s1063-5823(03)01013-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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41
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Torres ILS, Buffon A, Dantas G, Fürstenau CR, Böhmer AE, Battastini AMO, Sarkis JJF, Dalmaz C, Ferreira MBC. Chronic stress effects on adenine nucleotide hydrolysis in the blood serum and brain structures of rats. Pharmacol Biochem Behav 2002; 74:181-6. [PMID: 12376166 DOI: 10.1016/s0091-3057(02)00994-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
We have previously observed that adenosine 5'-diphosphate (ADP) hydrolysis was decreased 25% in spinal cord synaptosomes of chronically stressed male rats, while no changes were observed in ATPase activity. In the present study, we investigated the effect of chronic stress on the hydrolysis of adenine nucleotides in two cerebral structures (frontal cortex and hypothalamus) and in the blood serum of male rats. Adult male Wistar rats were submitted to 1-h restraint stress/day for 45 days (chronic) and were sacrificed 24 h after the last session of stress. Adenosine 5'-triphosphate (ATP) or ADP hydrolysis was assayed in the synaptosomal fraction obtained from the frontal cortex and hypothalamus of control and chronically stressed animals. No effects on ADP or ATP hydrolysis were observed in any of the cerebral structures analyzed after chronic stress. On the other hand, reduced ADP hydrolysis was observed in the blood serum of chronic stressed rats. It is possible that the effects observed in the blood serum may represent an adaptation to chronic stress and may reflect different functions of nucleotides and/or enzymes in these tissues. It is possible that altered levels of ADPase activity in the serum may be a biochemical marker for chronic stress situations.
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Affiliation(s)
- Iraci Luena S Torres
- Departamento de Bioqui;mica, Instituto de Ciências Básicas da Saúde, UFRGS, Ramiro Barcelos, 2600 Anexo, Lab. 32, 90035-003, RS, Porto Alegre, Brazil
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42
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Wood E, Broekman MJ, Kirley TL, Diani-Moore S, Tickner M, Drosopoulos JHF, Islam N, Park JI, Marcus AJ, Rifkind AB. Cell-type specificity of ectonucleotidase expression and upregulation by 2,3,7,8-tetrachlorodibenzo-p-dioxin. Arch Biochem Biophys 2002; 407:49-62. [PMID: 12392715 DOI: 10.1016/s0003-9861(02)00465-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We report here that induction of ectoATPase by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is cell-type specific and not a generalized response to aryl hydrocarbon (Ah) receptor activation. TCDD increased [14C]-ATP and -ADP metabolism in two mouse hepatoma lines, Hepa1c1c7 and Hepa1-6 cells, but not in human hepatoma HepG2 or HuH-7 cells, human umbilical vein endothelial cells (HUVEC), chick hepatoma (LMH) cells, or chick primary hepatocytes or cardiac myocytes, even though all of those cell types were Ah receptor-responsive, as evidenced by cytochrome P4501A induction. To determine whether the differences in ectonucleotidase responsiveness to TCDD might be related to differences in cell-type ectonucleotidase expression, ATP and ADP metabolite patterns, the products of several classes of ectonucleotidases including ectonucleoside triphosphate diphosphohydrolases (E-NTPDases), ectophosphodiesterase/pyrophosphatases (E-NPP enzymes) and ectoalkaline phosphatase activities were examined. Those patterns, together with results of enzyme assays, Western blotting, or semiquantitative RT-PCR show that NTPDase2 is the main ectonucleotidase for murine and human hepatoma cells, NTPDase3 for chick hepatocytes and LMH cells, and an E-NPP enzyme for chick cardiac myocytes. Evidence for NTPDase2 expression was lacking in all cells except the mouse and human hepatoma cells. TCDD increased expression of the NTPDase2 gene but only in the mouse and not in the human hepatoma cells. TCDD did not increase NTPDase3, NTPDase1, E-NPP, or alkaline phosphatase in any of the cell types examined. The failure of TCDD to increase ATP metabolism in HUVEC, chick LMH cells, hepatocytes, and cardiac myocytes can be attributed to their lack of NTPDase2 expression, while the increase in ATP metabolism by TCDD in the mouse but not the human hepatoma cells can be explained by differences in TCDD effects on mouse and human hepatoma NTPDase2 gene expression. In addition to characterizing effects of TCDD on ectonucleotidases, these studies reveal major differences in the complements of ectonucleotidases present in different cell types. It is likely that such differences are important for cell-specific susceptibility to extracellular nucleotide toxicity and responses to purinergic signaling.
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Affiliation(s)
- Emily Wood
- Department of Pharmacology, Weill Medical College of Cornell University, 1300 York Avenue, New York, NY 10021, USA
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43
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Birk AV, Broekman MJ, Gladek EM, Robertson HD, Drosopoulos JHF, Marcus AJ, Szeto HH. Role of extracellular ATP metabolism in regulation of platelet reactivity. ACTA ACUST UNITED AC 2002; 140:166-75. [PMID: 12271274 DOI: 10.1067/mlc.2002.126719] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Extracellular adenosine triphosphate (ATP) regulates platelet reactivity by way of direct action on platelet purinergic receptors or by hydrolysis to adenosine diphosphate (ADP). Subsequent metabolism of ATP and ADP to adenosine monophosphate (AMP) and adenosine inhibits platelet aggregation. Endothelial cell membrane-bound ecto-ATP/ADPase (CD39, E-NTPDase1) is thought to be the main regulator of platelet responsiveness. However, the findings in studies of CD39-knockout mice imply that nucleotidase(s) in plasma regulates circulating adenine nucleotides levels. Understanding extracellular ATP metabolism by CD39 and plasma nucleotidases is therefore important. In this study, alpha-phosphorus 32- and gamma-phosphorus 32-labeled ATP were rapidly metabolized directly to AMP and pyrophosphate in human plasma at pH 7.4, suggesting the presence of pyrophosphatase/phosphodiesterase-like activity. A specific phosphodiesterase substrate, p-nitrophenol-5'-TMP (p-Nph-5'-TMP), was readily hydrolyzed in human plasma. The antiaggregatory action of beta,gamma-methylene-ATP (AMPPCP) (5 micromol/L) was blocked by DMPX, an adenosine-receptor antagonist, suggesting that in plasma, AMPPCP was metabolized to AMP and adenosine. Recombinant soluble CD39 (solCD39) was used to assess the role of CD39 in ATP metabolism. As little as 0.25 microg/mL of solCD39 inhibited ADP-induced platelet aggregation. However, in the presence of ADP-free ATP (10 micromol/L), solCD39 induced platelet aggregation in a dose-dependent manner. Because AMPPCP could not substitute for ATP in solCD39-stimulated platelet aggregation, it is likely that ADP formation from ATP was required. Endogenous CD39 may thus have a hemostatic function by promoting ADP formation from released ATP, in addition to its antiaggregatory properties. A plasma nucleotidase hydrolyzes ATP directly to AMP. This prevents ADP accumulation and generates adenosine, a potent, locally acting inhibitor of platelet reactivity. The presence of both endothelial CD39 and plasma nucleotidase appears to be important in the maintenance of normal hemostasis and prevention of excessive platelet responsiveness.
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Affiliation(s)
- Alex V Birk
- Department of Pharmacology, Weill Medical College of Cornell University, New York, NY 10021, USA
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44
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Drosopoulos JHF. Roles of Asp54 and Asp213 in Ca2+ utilization by soluble human CD39/ecto-nucleotidase. Arch Biochem Biophys 2002; 406:85-95. [PMID: 12234494 DOI: 10.1016/s0003-9861(02)00414-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Soluble human CD39 (solCD39) rapidly metabolizes nucleotides, especially ADP released from activated platelets, thereby inhibiting further platelet activation and recruitment. Using alanine substitution mutagenesis, we established a functional role for aspartates D54 and D213 in solCD39. Kinetic analyses of D54A and D213A indicated decreased K(m)s of the mutants, compared to wild type, for the cofactor calcium and for the substrates ADP and ATP. These decreases in calcium and nucleotide affinity of the mutants were accompanied by increases in their rate of catalysis. The decreased affinity of the mutants for calcium was responsible for their diminished ability to reverse platelet aggregation in plasma anticoagulated with citrate, a known calcium chelator. Their ADPase activity in the presence of citrated plasma was also decreased, although this could be overcome with excess calcium. Thus, aspartates 54 and 213 are involved in calcium utilization and potentially involved in cation coordination with substrate in the catalytic pocket of solCD39.
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Affiliation(s)
- Joan H F Drosopoulos
- Research Service, Thrombosis Research Laboratory, VA New York Harbor Healthcare System, New York, NY 10010-5050, USA.
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45
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Mihaylova-Todorova ST, Todorov LD, Westfall DP. Enzyme kinetics and pharmacological characterization of nucleotidases released from the guinea pig isolated vas deferens during nerve stimulation: evidence for a soluble ecto-nucleoside triphosphate diphosphohydrolase-like ATPase and a soluble ecto-5'-nucleotidase-like AMPase. J Pharmacol Exp Ther 2002; 302:992-1001. [PMID: 12183656 DOI: 10.1124/jpet.102.033332] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Previously, we have demonstrated that stimulation of the sympathetic nerves of the guinea pig vas deferens evokes release not only of the cotransmitters ATP and norepinephrine but also of soluble nucleotidases that break down extracellular ATP, ADP, and AMP into adenosine. In this study we show that the apparent K(m) values of the releasable enzyme activity vary depending on which of these adenine nucleotides is used as initial substrate. The K(m) value for ATP was 33.6 +/- 2.3 microM, 21.0 +/- 2.3 microM for ADP, and 10.0 +/- 1.1 microM for AMP. The ratios of the V(max) values for each enzyme reaction were 4:2:3. We have also found a different sensitivity of the metabolism of ATP and AMP by releasable nucleotidases to known nucleotidase inhibitors. Suramin inhibited the breakdown of ATP by releasable nucleotidases in a noncompetitive manner and with a K(i) value of 53 microM, but had no effect on the breakdown of AMP. The 5'-nucleotidase inhibitor alpha,beta-methylene ADP inhibited the breakdown of AMP but not that of ATP. Concanavalin A inhibited the breakdown of AMP but had neither inhibitory nor facilitatory effects on the breakdown of ATP. 6-N,N-Diethyl-beta,gamma-dibromomethylene-D-ATP (ARL67156), an ecto-ATPase inhibitor, suppressed ATPase and AMPase activities, whereas NaN(3) (10 mM) affected neither reaction, but inhibited the ADP metabolism. Phosphatase- and phosphodiesterase inhibitors did not affect the activity of the releasable nucleotidases. This evidence suggests that the soluble nucleotidases released during neurogenic stimulation of the guinea pig vas deferens combine an ecto-5'-nucleotidase-like and an ecto-nucleoside triphosphate diphosphohydrolase-like activity.
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Affiliation(s)
- Svetlana T Mihaylova-Todorova
- Department of Pharmacology, University of Nevada School of Medicine, Howard Medical Sciences Building, Room 222, ms 318, Reno, NV 39557-0046, USA.
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Birk AV, Bubman D, Broekman MJ, Robertson HD, Drosopoulos JHF, Marcus AJ, Szeto HH. Role of a novel soluble nucleotide phospho-hydrolase from sheep plasma in inhibition of platelet reactivity: hemostasis, thrombosis, and vascular biology. THE JOURNAL OF LABORATORY AND CLINICAL MEDICINE 2002; 139:116-24. [PMID: 11919550 DOI: 10.1067/mlc.2002.121334] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Ecto- and exoenzymes that metabolize extracellular adenosine diphosphate (ADP), the major promoter of platelet activation and recruitment, are of potential clinical importance because they can metabolically prevent excessive thrombus growth. An ecto-ADPase (CD39, NTPDase1) has been identified on endothelial cells. We demonstrate that ADP and adenosine triphosphate (ATP) are rapidly metabolized to adenosine monophosphate (AMP) in sheep plasma at pH 7.4. This hydrolysis is sensitive to P(1), P(5)-di-(adenosine-5') pentaphosphate (Ap(5)A), and ethylene glycol bis (beta-aminoethyl ether) - N, N, N(-), N(-) tetra-acetate (EGTA) but insensitive to tetramisole (an alkaline phosphatase inhibitor). A specific phosphodiesterase substrate, p -nitrophenol-5'-thymidine monophosphate (TMP) (p -Nph-5'-TMP), was readily hydrolyzed in sheep plasma at a rate of approximately 0.25 nmol/min/mg protein, and this hydrolysis was inhibited by ADP, ATP, and Ap(5)A. Furthermore, 200-fold purified p -Nph-5'-TMP-hydrolyzing activity also hydrolyzed ATP and ADP directly to AMP. When ADP was preincubated in plasma, its ability to induce platelet aggregation was inhibited in a time-dependent manner. This effect was abolished by Ap(5)A. The inhibitory effects on platelet aggregation correlated with hydrolysis of the ADP in plasma. These data suggest that the endogenous soluble plasma phosphohydrolase metabolizes ATP and ADP by means of cleavage of the alpha-beta-phosphodiester bond of nucleoside 5'-phosphate derivatives. This novel biochemical activity inhibits platelet reactivity through hydrolysis of extracellular nucleotides released by activated platelets during (patho)physiological processes, serving a homeostatic and antithrombotic function in vivo.
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Affiliation(s)
- Alex V Birk
- Division of Hematology and Medical Oncology, Department of Medicine, Weill Medical College of Cornell University, New York, New York 10021, USA
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Torres ILS, Buffon A, Silveira PP, Duarte MZD, Bassani MG, Oliveira SS, Battastini AMO, Sarkis JJF, Dalmaz C, Ferreira MBC. Effect of chronic and acute stress on ectonucleotidase activities in spinal cord. Physiol Behav 2002; 75:1-5. [PMID: 11890946 DOI: 10.1016/s0031-9384(01)00605-9] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
We have previously observed that, while acute stress induces analgesia, chronic stress causes a hyperalgesic response in male rats. No effect was observed in females. There is increasing evidence that both ATP and adenosine can modulate pain. Extracellular ATP and ADP are hydrolyzed by an apyrase in synaptosomes from the peripheral and central nervous systems. In the present study, we investigated the effect of chronic and acute stress on ATPase-ADPase and 5'-nucleotidase activities in spinal cord of male and female rats. Adult male and female Wistar rats were submitted to 1 h restraint stress/day for 1 day (acute) or 40 days (chronic) and were sacrificed 24 h later. ATPase-ADPase activities were assayed in the synaptosomal fraction obtained from the spinal cord of control and stressed animals. ADP hydrolysis was decreased 25% in chronically stressed males, while no change was observed on ATPase activity. There was an increase in the 5'-nucleotidase activity in the same group. No effect on ADPase, ATPase or on 5'-nucleotidase activity was observed in females with chronic stress, or after acute stress neither in males or females. Chronic stress reduced ADP hydrolysis and increased 5'-nucleotidase activity in the spinal cord in male rats.
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Affiliation(s)
- Iraci Lucena S Torres
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, UFRGS, 90035-003, Porto Alegre, RS, Brazil.
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Chen W, Guidotti G. The metal coordination of sCD39 during ATP hydrolysis. BMC BIOCHEMISTRY 2001; 2:9. [PMID: 11591225 PMCID: PMC57746 DOI: 10.1186/1471-2091-2-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/25/2001] [Accepted: 09/12/2001] [Indexed: 11/23/2022]
Abstract
BACKGROUND The hydrolysis of ATP and ADP by ecto-nucleoside triphosphate diphosphohydrolase 1 (CD39) requires divalent cations, like Ca2+ and Mg2+. In spite of considerable work, it is not clear whether divalent cations bind to the enzyme in the absence of nucleotide or only as nucleotide-Me+2 complex. Here we study the protein ligands for Me+2. RESULTS When VO2+ was used as a substitute for Ca2+, the ATPase activity of soluble CD39 was 25% of that with Ca2+ as cofactor. Protein ligands of the VO2+-nucleotide complex bound to the catalytic site of soluble CD39 were characterized by electron paramagnetic resonance (EPR) spectroscopy. The EPR spectrum contained one species designated T with VO2+-AMPPNP as ligand. Two species D1 and D2 were observed when VO2+-AMPCP was bound to soluble CD39. The results suggest that species D1 and D2 represent the metal-ADP complexes at the catalytic site of soluble CD39 corresponding to the intermediate formed during ATP hydrolysis and the substrate for further hydrolysis, respectively. CONCLUSIONS VO2+ can functionally substitute for Ca2+ as a cofactor of sCD39, and it produces four different EPR features when bound in the presence of different nucleotides or in the absence of nucleotide. The metal coordination for each conformation corresponding to each EPR species is proposed, and the mechanism of sCD39 catalysis is discussed.
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Affiliation(s)
- Wei Chen
- Department of Molecular and Cellular Biology, Harvard University, 7 Divinity Avenue, Cambridge, MA 02138, USA
| | - Guido Guidotti
- Department of Molecular and Cellular Biology, Harvard University, 7 Divinity Avenue, Cambridge, MA 02138, USA
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