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Jung C, Rezar R, Wischmann P, Masyuk M, Datz C, Bruno RR, Kelm M, Wernly B. The role of anemia on admission in acute coronary syndrome - An umbrella review of systematic reviews and meta-analyses. Int J Cardiol 2022; 367:1-10. [PMID: 36055474 DOI: 10.1016/j.ijcard.2022.08.052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Revised: 08/10/2022] [Accepted: 08/24/2022] [Indexed: 01/28/2023]
Abstract
INTRODUCTION The role of erythrocytes in the acute coronary syndrome (ACS) is complex. The aim of this review in terms of PICO (P: patients; I: intervention; C: comparison; O: outcome) was to summarize systematic reviews in patients (P) with acute coronary syndrome, evaluating the effects of (I) 1) iron deficiency, 2) administration of an erythropoiesis-stimulating agent (ESA), 3) anemia on admission, 4) red blood cell transfusion, 5) a restrictive transfusion strategy in comparison (C) to 1) no iron deficiency, 2) no ESA 3) no anemia on admission, 4) no red blood cell transfusion, 5) a liberal transfusion strategy on mortality (O). METHODS We used AMSTAR2 to assess the methodological quality of systematic reviews and grade the available research. The primary endpoint was all-cause mortality. RESULTS Using the data from 2,787,005 patients, the following conditions were associated with worse outcome in patients with ACS: anemia on admission (RR 2.08 95%CI 1.70-2.55) and transfusion (1.93 95%CI 1.12-3.34) of red blood cells. A liberal transfusion (RR 0.86 95%CI 0.70-1-05), administration of ESA (RR 0.55 95%CI 0.22-1.33) and iron deficiency (OR 1.24 95%CI 0.12-13.13) were not associated with altered all-cause mortality. CONCLUSION Patients suffering from ACS and anemia on admission are at particular risk for adverse outcome. There is evidence of associations between adverse outcomes and receiving red blood cell transfusions.
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Affiliation(s)
- Christian Jung
- Department of Cardiology, Pulmonology and Vascular Medicine, Medical Faculty, Heinrich-Heine-University Düsseldorf, Moorenstraße 5, 40225 Duesseldorf, Germany.
| | - Richard Rezar
- Department of Cardiology and Intensive Care Medicine, Paracelsus Medical University of Salzburg, Müllner Hauptstraße 48, 5020 Salzburg, Austria.
| | - Patricia Wischmann
- Department of Cardiology, Pulmonology and Vascular Medicine, Medical Faculty, Heinrich-Heine-University Düsseldorf, Moorenstraße 5, 40225 Duesseldorf, Germany
| | - Maryna Masyuk
- Department of Cardiology, Pulmonology and Vascular Medicine, Medical Faculty, Heinrich-Heine-University Düsseldorf, Moorenstraße 5, 40225 Duesseldorf, Germany
| | - Christian Datz
- Department of Internal Medicine, Teaching Hospital of the Paracelsus Medical University Salzburg, General Hospital Oberndorf, Paracelsus Medical University Salzburg, Oberndorf, Austria.
| | - Raphael Romano Bruno
- Department of Cardiology, Pulmonology and Vascular Medicine, Medical Faculty, Heinrich-Heine-University Düsseldorf, Moorenstraße 5, 40225 Duesseldorf, Germany
| | - Malte Kelm
- Department of Cardiology, Pulmonology and Vascular Medicine, Medical Faculty, Heinrich-Heine-University Düsseldorf, Moorenstraße 5, 40225 Duesseldorf, Germany
| | - Bernhard Wernly
- Department of Internal Medicine, Teaching Hospital of the Paracelsus Medical University Salzburg, General Hospital Oberndorf, Paracelsus Medical University Salzburg, Oberndorf, Austria; Center for Public Health and Healthcare Research, Paracelsus Medical University of Salzburg, Strubergasse 21, 5020 Salzburg, Austria
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Leal Denis MF, Lefevre SD, Alvarez CL, Lauri N, Enrique N, Rinaldi DE, Gonzalez-Lebrero R, Vecchio LE, Espelt MV, Stringa P, Muñoz-Garay C, Milesi V, Ostuni MA, Herlax V, Schwarzbaum PJ. Regulation of extracellular ATP of human erythrocytes treated with α-hemolysin. Effects of cell volume, morphology, rheology and hemolysis. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2019; 1866:896-915. [PMID: 30726708 DOI: 10.1016/j.bbamcr.2019.01.018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Revised: 01/10/2019] [Accepted: 01/30/2019] [Indexed: 12/17/2022]
Abstract
Alpha-hemolysin (HlyA) of uropathogenic strains of Escherichia coli irreversibly binds to human erythrocytes (RBCs) and triggers activation of ATP release and metabolic changes ultimately leading to hemolysis. We studied the regulation of extracellular ATP (ATPe) of RBCs exposed to HlyA. Luminometry was used to assess ATP release and ATPe hydrolysis, whereas changes in cell volume and morphology were determined by electrical impedance, ektacytometry and aggregometry. Exposure of RBCs to HlyA induced a strong increase of [ATPe] (3-36-fold) and hemolysis (1-44-fold), partially compensated by [ATPe] hydrolysis by ectoATPases and intracellular ATPases released by dead cells. Carbenoxolone, a pannexin 1 inhibitor, partially inhibited ATP release (43-67%). The un-acylated toxin ProHlyA and the deletion analog HlyA∆914-936 were unable to induce ATP release or hemolysis. For HlyA treated RBCs, a data driven mathematical model showed that simultaneous lytic and non-lytic release mainly governed ATPe kinetics, while ATPe hydrolysis became important after prolonged toxin exposure. HlyA induced a 1.5-fold swelling, while blocking this swelling reduced ATP release by 77%. Blocking ATPe activation of purinergic P2X receptors reduced swelling by 60-80%. HlyA-RBCs showed an acute 1.3-2.2-fold increase of Ca2+i, increased crenation and externalization of phosphatidylserine. Perfusion of HlyA-RBCs through adhesion platforms showed strong adhesion to activated HMEC cells, followed by rapid detachment. HlyA exposed RBCs exhibited increased sphericity under osmotic stress, reduced elongation under shear stress, and very low aggregation in viscous media. Overall results showed that HlyA-RBCs displayed activated ATP release, high but weak adhesivity, low deformability and aggregability and high sphericity.
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Affiliation(s)
- M F Leal Denis
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Química y Fisico-Química Biológicas (IQUIFIB) "Prof. Alejandro C. Paladini", Facultad de Farmacia y Bioquímica, Junín 956 Buenos Aires, Argentina.; Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Departamento de Química Analítica, Cátedra de Química Química Analítica y Fisicoquímica, Junín 956 Buenos Aires, Argentina
| | - S D Lefevre
- UMR-S1134, Integrated Biology of Red Blood Cells, INSERM, Université Paris Diderot, Sorbonne Paris Cité, Université de la Réunion, Université des Antilles, F-75015 Paris, France.; Institut National de la Transfusion Sanguine, Laboratoire d'Excellence GR-Ex, F-75015 Paris, France
| | - C L Alvarez
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Química y Fisico-Química Biológicas (IQUIFIB) "Prof. Alejandro C. Paladini", Facultad de Farmacia y Bioquímica, Junín 956 Buenos Aires, Argentina.; Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Biodiversidad y Biología Experimental, Intendente Güiraldes 2160 Buenos Aires, Argentina
| | - N Lauri
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Química y Fisico-Química Biológicas (IQUIFIB) "Prof. Alejandro C. Paladini", Facultad de Farmacia y Bioquímica, Junín 956 Buenos Aires, Argentina.; Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Biológica. Cátedra de Química Biológica Superior, Junín 956 Buenos Aires, Argentina
| | - N Enrique
- Universidad Nacional de La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Estudios Inmunológicos y Fisiopatológicos (IIFP), Facultad de Ciencias Exactas, Calle 47 y 115 La Plata, Argentina.; Universidad Nacional de la Plata, Facultad de Ciencias Exactas, Departamento de Ciencias Biológicas, Cátedra de Fisiología, Calle 47, Casco Urbano, La Plata, Argentina
| | - D E Rinaldi
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Química y Fisico-Química Biológicas (IQUIFIB) "Prof. Alejandro C. Paladini", Facultad de Farmacia y Bioquímica, Junín 956 Buenos Aires, Argentina.; Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Departamento de Química Biológica, Cátedra de Química Biológica, Junín 956 Buenos Aires, Argentina
| | - R Gonzalez-Lebrero
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Química y Fisico-Química Biológicas (IQUIFIB) "Prof. Alejandro C. Paladini", Facultad de Farmacia y Bioquímica, Junín 956 Buenos Aires, Argentina.; Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Departamento de Química Biológica, Cátedra de Química Biológica, Junín 956 Buenos Aires, Argentina
| | - L E Vecchio
- Universidad Nacional de La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Estudios Inmunológicos y Fisiopatológicos (IIFP), Facultad de Ciencias Exactas, Calle 47 y 115 La Plata, Argentina.; Universidad Nacional de la Plata, Facultad de Ciencias Exactas, Departamento de Ciencias Biológicas, Cátedra de Fisiología, Calle 47, Casco Urbano, La Plata, Argentina
| | - M V Espelt
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Química y Fisico-Química Biológicas (IQUIFIB) "Prof. Alejandro C. Paladini", Facultad de Farmacia y Bioquímica, Junín 956 Buenos Aires, Argentina.; Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Biológica. Cátedra de Química Biológica Superior, Junín 956 Buenos Aires, Argentina
| | - P Stringa
- Universidad Nacional de La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Estudios Inmunológicos y Fisiopatológicos (IIFP), Facultad de Ciencias Exactas, Calle 47 y 115 La Plata, Argentina.; Universidad Favaloro, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Medicina Traslacional, Trasplante y Bioingeniería (IMETTyB), Av. Entre Ríos 495, Buenos Aires, Argentina.; Universidad Nacional de La Plata, Laboratorio de Trasplante de Órganos y Tejidos, Facultad de Ciencias, Calle 60 y 120, La Plata, Argentina
| | - C Muñoz-Garay
- Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México (UNAM), Av. Universidad s/n, Cuernavaca, Mexico
| | - V Milesi
- Universidad Nacional de La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Estudios Inmunológicos y Fisiopatológicos (IIFP), Facultad de Ciencias Exactas, Calle 47 y 115 La Plata, Argentina.; Universidad Nacional de la Plata, Facultad de Ciencias Exactas, Departamento de Ciencias Biológicas, Cátedra de Fisiología, Calle 47, Casco Urbano, La Plata, Argentina
| | - M A Ostuni
- UMR-S1134, Integrated Biology of Red Blood Cells, INSERM, Université Paris Diderot, Sorbonne Paris Cité, Université de la Réunion, Université des Antilles, F-75015 Paris, France.; Institut National de la Transfusion Sanguine, Laboratoire d'Excellence GR-Ex, F-75015 Paris, France
| | - V Herlax
- Universidad Nacional de La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP) "Prof. Dr. Rodolfo R. Brenner", Facultad de Ciencias Médicas, Av. 60 y Av. 120, La Plata, Argentina.; Universidad Nacional de La Plata, Facultad de Ciencias Médicas, Av. 60 y Av. 120, La Plata, Argentina
| | - P J Schwarzbaum
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Química y Fisico-Química Biológicas (IQUIFIB) "Prof. Alejandro C. Paladini", Facultad de Farmacia y Bioquímica, Junín 956 Buenos Aires, Argentina.; Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Biológica. Cátedra de Química Biológica Superior, Junín 956 Buenos Aires, Argentina..
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Druggable Targets in Cyclic Nucleotide Signaling Pathways in Apicomplexan Parasites and Kinetoplastids against Disabling Protozoan Diseases in Humans. Int J Mol Sci 2019; 20:ijms20010138. [PMID: 30609697 PMCID: PMC6337498 DOI: 10.3390/ijms20010138] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2018] [Revised: 12/19/2018] [Accepted: 12/24/2018] [Indexed: 12/20/2022] Open
Abstract
Cell signaling in eukaryotes is an evolutionarily conserved mechanism to respond and adapt to various environmental changes. In general, signal sensation is mediated by a receptor which transfers the signal to a cascade of effector proteins. The cyclic nucleotides 3′,5′-cyclic adenosine monophosphate (cAMP) and 3′,5′-cyclic guanosine monophosphate (cGMP) are intracellular messengers mediating an extracellular stimulus to cyclic nucleotide-dependent kinases driving a change in cell function. In apicomplexan parasites and kinetoplastids, which are responsible for a variety of neglected, tropical diseases, unique mechanisms of cyclic nucleotide signaling are currently identified. Collectively, cyclic nucleotides seem to be essential for parasitic proliferation and differentiation. However, there is no a genomic evidence for canonical G-proteins in these parasites while small GTPases and secondary effector proteins with structural differences to host orthologues occur. Database entries encoding G-protein-coupled receptors (GPCRs) are still without functional proof. Instead, signals from the parasite trigger GPCR-mediated signaling in the host during parasite invasion and egress. The role of cyclic nucleotide signaling in the absence of G-proteins and GPCRs, with a particular focus on small GTPases in pathogenesis, is reviewed here. Due to the absence of G-proteins, apicomplexan parasites and kinetoplastids may use small GTPases or their secondary effector proteins and host canonical G-proteins during infection. Thus, the feasibility of targeting cyclic nucleotide signaling pathways in these parasites, will be an enormous challenge for the identification of selective, pharmacological inhibitors since canonical host proteins also contribute to pathogenesis.
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Zhao Y, Wang X, Wang R, Chen D, Noviana M, Zhu H. Nitric oxide inhibits hypoxia-induced impairment of human RBC deformability through reducing the cross-linking of membrane protein band 3. J Cell Biochem 2018; 120:305-320. [PMID: 30218451 DOI: 10.1002/jcb.27359] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Accepted: 06/26/2018] [Indexed: 12/26/2022]
Abstract
AIM Nitric oxide (NO) prevents the decline of RBC deformability under high altitude and other ischemic and hypoxic conditions, but the clear mechanisms remain unknown. Here, we have carried out a systematic study to find the mechanisms of NO-induced regulation of RBC deformability under hypoxia. METHODS NO levels, RBCs membrane elongation index (EI), membrane protein band 3 methemoglobin (MetHb) were determined during hypoxia (0 to 120 minutes). To validate the role of NO in regulating RBC deformability, tests were also performed with a NO donor (sodium nitroprusside) or a NO synthase inhibitor (l-nitro-arginine methylester) under 60 minutes hypoxia. RESULTS Hypoxia for 45 minutes increased NO levels from 25.65 ± 1.95 to 35.26 ± 2.01 μmol/L, and there was a plateau after 60 minutes hypoxia. The EI did not change before 45 minutes hypoxia, but decreased from 0.567 ± 0.019 to 0.409 ± 0.042 (30 Pa) after 60 minutes hypoxia. The cross-linking of band 3 and phosphotyrosine increased after 45 minutes hypoxia. All can be alleviated by supplement NO and aggregated by inhibiting NOS. However, the MetHb was not present this trend. CONCLUSION NO may prevent decreased of RBCs deformability through reducing the cross-linking of membrane band 3 under hypoxia; this helps microvascular perfusion of RBCs during ischemic and hypoxic disease states.
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Affiliation(s)
- Yajin Zhao
- Key Laboratory of Biorheological Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Chongqing, China
| | - Xiang Wang
- Key Laboratory of Biorheological Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Chongqing, China
| | - Ruofeng Wang
- Key Laboratory of Biorheological Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Chongqing, China
| | - Dong Chen
- Key Laboratory of Biorheological Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Chongqing, China
| | - Milody Noviana
- Key Laboratory of Biorheological Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Chongqing, China
| | - Hongliang Zhu
- Key Laboratory of Biorheological Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Chongqing, China
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Marginedas-Freixa I, Alvarez CL, Moras M, Leal Denis MF, Hattab C, Halle F, Bihel F, Mouro-Chanteloup I, Lefevre SD, Le Van Kim C, Schwarzbaum PJ, Ostuni MA. Human erythrocytes release ATP by a novel pathway involving VDAC oligomerization independent of pannexin-1. Sci Rep 2018; 8:11384. [PMID: 30061676 PMCID: PMC6065367 DOI: 10.1038/s41598-018-29885-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Accepted: 07/20/2018] [Indexed: 12/14/2022] Open
Abstract
We previously demonstrated that the translocase protein TSPO2 together with the voltage-dependent anion channel (VDAC) and adenine nucleotide transporter (ANT) were involved in a membrane transport complex in human red blood cells (RBCs). Because VDAC was proposed as a channel mediating ATP release in RBCs, we used TSPO ligands together with VDAC and ANT inhibitors to test this hypothesis. ATP release was activated by TSPO ligands, and blocked by inhibitors of VDAC and ANT, while it was insensitive to pannexin-1 blockers. TSPO ligand increased extracellular ATP (ATPe) concentration by 24–59% over the basal values, displaying an acute increase in [ATPe] to a maximal value, which remained constant thereafter. ATPe kinetics were compatible with VDAC mediating a fast but transient ATP efflux. ATP release was strongly inhibited by PKC and PKA inhibitors as well as by depleting intracellular cAMP or extracellular Ca2+, suggesting a mechanism involving protein kinases. TSPO ligands favoured VDAC polymerization yielding significantly higher densities of oligomeric bands than in unstimulated cells. Polymerization was partially inhibited by decreasing Ca2+ and cAMP contents. The present results show that TSPO ligands induce polymerization of VDAC, coupled to activation of ATP release by a supramolecular complex involving VDAC, TSPO2 and ANT.
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Affiliation(s)
- Irene Marginedas-Freixa
- UMR-S1134, Integrated Biology of Red Blood Cells, INSERM, Université Paris Diderot, Sorbonne Paris Cité, Université de la Réunion, Université des Antilles, F-75015, Paris, France.,Institut National de la Transfusion Sanguine, Laboratoire d'Excellence GR-Ex, F-75015, Paris, France
| | - Cora Lilia Alvarez
- Instituto de Química y Fisico-Química Biológicas "Prof. Alejandro C. Paladini", UBA, CONICET, Facultad de Farmacia y Bioquímica, Junín 956, Buenos Aires, Argentina.,Universidad de Buenos Aires. Facultad Ciencias Exactas y Naturales, Departamento de Biodiversidad y Biología Experimental, Buenos Aires, Argentina
| | - Martina Moras
- UMR-S1134, Integrated Biology of Red Blood Cells, INSERM, Université Paris Diderot, Sorbonne Paris Cité, Université de la Réunion, Université des Antilles, F-75015, Paris, France.,Institut National de la Transfusion Sanguine, Laboratoire d'Excellence GR-Ex, F-75015, Paris, France
| | - María Florencia Leal Denis
- Instituto de Química y Fisico-Química Biológicas "Prof. Alejandro C. Paladini", UBA, CONICET, Facultad de Farmacia y Bioquímica, Junín 956, Buenos Aires, Argentina.,Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Departamento de Química Analítica y Fisicoquímica, Cátedra de Química Analítica, Buenos Aires, Argentina
| | - Claude Hattab
- UMR-S1134, Integrated Biology of Red Blood Cells, INSERM, Université Paris Diderot, Sorbonne Paris Cité, Université de la Réunion, Université des Antilles, F-75015, Paris, France.,Institut National de la Transfusion Sanguine, Laboratoire d'Excellence GR-Ex, F-75015, Paris, France
| | - François Halle
- UMR7200, Laboratoire d'Innovation Thérapeutique, Faculty of Pharmacy, University of Strasbourg, CNRS, 67400, Illkirch Graffenstaden, France
| | - Frédéric Bihel
- UMR7200, Laboratoire d'Innovation Thérapeutique, Faculty of Pharmacy, University of Strasbourg, CNRS, 67400, Illkirch Graffenstaden, France
| | - Isabelle Mouro-Chanteloup
- UMR-S1134, Integrated Biology of Red Blood Cells, INSERM, Université Paris Diderot, Sorbonne Paris Cité, Université de la Réunion, Université des Antilles, F-75015, Paris, France.,Institut National de la Transfusion Sanguine, Laboratoire d'Excellence GR-Ex, F-75015, Paris, France
| | - Sophie Denise Lefevre
- UMR-S1134, Integrated Biology of Red Blood Cells, INSERM, Université Paris Diderot, Sorbonne Paris Cité, Université de la Réunion, Université des Antilles, F-75015, Paris, France.,Institut National de la Transfusion Sanguine, Laboratoire d'Excellence GR-Ex, F-75015, Paris, France
| | - Caroline Le Van Kim
- UMR-S1134, Integrated Biology of Red Blood Cells, INSERM, Université Paris Diderot, Sorbonne Paris Cité, Université de la Réunion, Université des Antilles, F-75015, Paris, France.,Institut National de la Transfusion Sanguine, Laboratoire d'Excellence GR-Ex, F-75015, Paris, France
| | - Pablo Julio Schwarzbaum
- Instituto de Química y Fisico-Química Biológicas "Prof. Alejandro C. Paladini", UBA, CONICET, Facultad de Farmacia y Bioquímica, Junín 956, Buenos Aires, Argentina.,Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Departamento de Química Biológica. Cátedra de Química Biológica Superior, Buenos Aires, Argentina
| | - Mariano Anibal Ostuni
- UMR-S1134, Integrated Biology of Red Blood Cells, INSERM, Université Paris Diderot, Sorbonne Paris Cité, Université de la Réunion, Université des Antilles, F-75015, Paris, France. .,Institut National de la Transfusion Sanguine, Laboratoire d'Excellence GR-Ex, F-75015, Paris, France.
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Kuchel PW, Shishmarev D. Accelerating metabolism and transmembrane cation flux by distorting red blood cells. SCIENCE ADVANCES 2017; 3:eaao1016. [PMID: 29057326 PMCID: PMC5647125 DOI: 10.1126/sciadv.aao1016] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Accepted: 09/21/2017] [Indexed: 06/07/2023]
Abstract
Under static conditions, mammalian red blood cells (RBCs) require a continuous supply of energy, typically via glucose, to maintain their biconcave disc shape. Mechanical distortion, in a complementary way, should lead to increased energy demand that is manifest in accelerated glycolysis. The experimental challenge in observing this phenomenon was met by reversibly and reproducibly distorting the cells and noninvasively measuring glycolytic flux. This was done with a gel-distorting device that was coupled with 13C nuclear magnetic resonance (NMR) spectroscopy. We measured [3-13C]l-lactate production from [1,6-13C]d-glucose in the RBCs suspended in gelatin gels, and up to 90% rate enhancements were recorded. Thus, for the first time, we present experiments that demonstrate the linkage of mechanical distortion to metabolic changes in whole mammalian cells. In seeking a mechanism for the linkage between shape and energy supply, we measured transmembrane cation flux with Cs+ (as a K+ congener) using 133Cs NMR spectroscopy, and the cation flux was increased up to fivefold. The postulated mechanism for these notable (in terms of whole-body energy consumption) responses is stimulation of Ca-adenosine triphosphatase by increased transmembrane flux of Ca2+ via the channel protein Piezo1 and increased glycolysis because its flux is adenosine triphosphate demand-regulated.
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Purinergic control of red blood cell metabolism: novel strategies to improve red cell storage quality. BLOOD TRANSFUSION = TRASFUSIONE DEL SANGUE 2017; 15:535-542. [PMID: 28488967 DOI: 10.2450/2017.0366-16] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Accepted: 02/23/2017] [Indexed: 02/08/2023]
Abstract
Transfusion of stored blood is regarded as one of the great advances in modern medicine. However, during storage in the blood bank, red blood cells (RBCs) undergo a series of biochemical and biomechanical changes that affect cell morphology and physiology and potentially impair transfusion safety and efficacy. Despite reassuring evidence from clinical trials, it is universally accepted that the storage lesion(s) results in the altered physiology of long-stored RBCs and helps explain the rapid clearance of up to one-fourth of long-stored RBCs from the recipient's bloodstream at 24 hours after administration. These considerations explain the importance of understanding and mitigating the storage lesion. With the emergence of new technologies that have enabled large-scale and in-depth screening of the RBC metabolome and proteome, recent studies have provided novel insights into the molecule-level metabolic changes underpinning the accumulation of storage lesions to RBCs in the blood bank and alternative storage strategies to mitigate such lesion(s). These approaches borrow from recent insights on the biochemistry of RBC adaptation to high altitude hypoxia. We recently conducted investigations in genetically modified mice and revealed novel insights into the role of adenosine signalling in response to hypoxia as a previously unrecognised cascade regulating RBC glucose metabolism and increasing O2 release, while decreasing inflammation and tissue injuries in animal models. Here, we will discuss the molecular mechanisms underlying the role of purinergic molecules, including adenosine and adenosine triphosphate in manipulating RBCs and blood vessels in response to hypoxia. We will also speculate about new therapeutic possibilities to improve the quality of stored RBCs and the prognosis after transfusion.
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Purpura M, Rathmacher JA, Sharp MH, Lowery RP, Shields KA, Partl JM, Wilson JM, Jäger R. Oral Adenosine-5'-triphosphate (ATP) Administration Increases Postexercise ATP Levels, Muscle Excitability, and Athletic Performance Following a Repeated Sprint Bout. J Am Coll Nutr 2017; 36:177-183. [PMID: 28080323 DOI: 10.1080/07315724.2016.1246989] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
OBJECTIVE Oral adenosine-5'-triphosphate (ATP) administration has failed to increase plasma ATP levels; however, chronic supplementation with ATP has shown to increase power, strength, lean body mass, and blood flow in trained athletes. The purpose of this study was to investigate the effects of ATP supplementation on postexercise ATP levels and on muscle activation and excitability and power following a repeated sprint bout. METHODS In a double-blind, placebo-controlled, randomized design, 42 healthy male individuals were given either 400 mg of ATP as disodium salt or placebo for 2 weeks prior to an exercise bout. During the exercise bout, muscle activation and excitability (ME, ratio of power output to muscle activation) and Wingate test peak power were measured during all sprints. ATP and metabolites were measured at baseline, after supplementation, and immediately following exercise. RESULTS Oral ATP supplementation prevented a drop in ATP, adenosine-5'-diphosphate (ADP), and adenosine-5'-monophosphate (AMP) levels postexercise (p < 0.05). No group by time interaction was observed for muscle activation. Following the supplementation period, muscle excitability significantly decreased in later bouts 8, 9, and 10 in the placebo group (-30.5, -28.3, and -27.9%, respectively; p < 0.02), whereas ATP supplementation prevented the decline in later bouts. ATP significantly increased Wingate peak power in later bouts compared to baseline (bout 8: +18.3%, bout 10: +16.3%). CONCLUSIONS Oral ATP administration prevents exercise-induced declines in ATP and its metabolite and enhances peak power and muscular excitability, which may be beneficial for sports requiring repeated high-intensity sprinting bouts.
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Affiliation(s)
| | - John A Rathmacher
- c Applied Science and Performance Institute , Tampa , Florida , USA.,d Metabolic Technologies Inc. , Ames , Iowa , USA.,e Department of Animal Sciences , Iowa State University , Ames , Iowa , USA
| | - Matthew H Sharp
- b Department of Health Sciences and Human Performance , The University of Tampa , Tampa , Florida , USA
| | - Ryan P Lowery
- c Applied Science and Performance Institute , Tampa , Florida , USA
| | - Kevin A Shields
- b Department of Health Sciences and Human Performance , The University of Tampa , Tampa , Florida , USA
| | - Jeremy M Partl
- b Department of Health Sciences and Human Performance , The University of Tampa , Tampa , Florida , USA
| | - Jacob M Wilson
- c Applied Science and Performance Institute , Tampa , Florida , USA
| | - Ralf Jäger
- a Increnovo LLC , Milwaukee , Wisconsin , USA
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9
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Libert N, Harrois A, Duranteau J. Haemodynamic coherence in haemorrhagic shock. Best Pract Res Clin Anaesthesiol 2016; 30:429-435. [DOI: 10.1016/j.bpa.2016.11.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Accepted: 11/07/2016] [Indexed: 01/22/2023]
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10
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Leal Denis MF, Alvarez HA, Lauri N, Alvarez CL, Chara O, Schwarzbaum PJ. Dynamic Regulation of Cell Volume and Extracellular ATP of Human Erythrocytes. PLoS One 2016; 11:e0158305. [PMID: 27355484 PMCID: PMC4927150 DOI: 10.1371/journal.pone.0158305] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2016] [Accepted: 06/13/2016] [Indexed: 11/18/2022] Open
Abstract
Introduction The peptide mastoparan 7 (MST7) triggered in human erythrocytes (rbcs) the release of ATP and swelling. Since swelling is a well-known inducer of ATP release, and extracellular (ATPe), interacting with P (purinergic) receptors, can affect cell volume (Vr), we explored the dynamic regulation between Vr and ATPe. Methods and Treatments We made a quantitative assessment of MST7-dependent kinetics of Vr and of [ATPe], both in the absence and presence of blockers of ATP efflux, swelling and P receptors. Results In rbcs 10 μM MST7 promoted acute, strongly correlated changes in [ATPe] and Vr. Whereas MST7 induced increases of 10% in Vr and 190 nM in [ATPe], blocking swelling in a hyperosmotic medium + MST7 reduced [ATPe] by 40%. Pre-incubation of rbcs with 10 μM of either carbenoxolone or probenecid, two inhibitors of the ATP conduit pannexin 1, reduced [ATPe] by 40–50% and swelling by 40–60%, while in the presence of 80 U/mL apyrase, an ATPe scavenger, cell swelling was prevented. While exposure to 10 μM NF110, a blocker of ATP-P2X receptors mediating sodium influx, reduced [ATPe] by 48%, and swelling by 80%, incubation of cells in sodium free medium reduced swelling by 92%. Analysis and Discussion Results were analyzed by means of a mathematical model where ATPe kinetics and Vr kinetics were mutually regulated. Model dependent fit to experimental data showed that, upon MST7 exposure, ATP efflux required a fast 1960-fold increase of ATP permeability, mediated by two kinetically different conduits, both of which were activated by swelling and inactivated by time. Both experimental and theoretical results suggest that, following MST7 exposure, ATP is released via two conduits, one of which is mediated by pannexin 1. The accumulated ATPe activates P2X receptors, followed by sodium influx, resulting in cell swelling, which in turn further activates ATP release. Thus swelling and P2X receptors constitute essential components of a positive feedback loop underlying ATP-induced ATP release of rbcs.
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Affiliation(s)
- M. Florencia Leal Denis
- Instituto de Química y Fisicoquímica Biológicas “Prof. A. C. Paladini”, Universidad de Buenos Aires, CONICET, FFyB, Buenos Aires, Argentina
| | - H. Ariel Alvarez
- Instituto de Física de Líquidos y Sistemas Biológicos (IFLYSIB), CONICET, Universidad Nacional de La Plata (UNLP), La Plata, Argentina
| | - Natalia Lauri
- Instituto de Química y Fisicoquímica Biológicas “Prof. A. C. Paladini”, Universidad de Buenos Aires, CONICET, FFyB, Buenos Aires, Argentina
| | - Cora L. Alvarez
- Instituto de Química y Fisicoquímica Biológicas “Prof. A. C. Paladini”, Universidad de Buenos Aires, CONICET, FFyB, Buenos Aires, Argentina
| | - Osvaldo Chara
- Instituto de Física de Líquidos y Sistemas Biológicos (IFLYSIB), CONICET, Universidad Nacional de La Plata (UNLP), La Plata, Argentina
- Center for Information Services and High Performance Computing (ZIH), Technische Universität Dresden (TUD), Dresden, Germany
| | - Pablo J. Schwarzbaum
- Instituto de Química y Fisicoquímica Biológicas “Prof. A. C. Paladini”, Universidad de Buenos Aires, CONICET, FFyB, Buenos Aires, Argentina
- * E-mail:
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Joy JM, Vogel RM, Moon JR, Falcone PH, Mosman MM, Kim MP. Twelve weeks supplementation with an extended-release caffeine and ATP-enhancing supplement may improve body composition without affecting hematology in resistance-trained men. J Int Soc Sports Nutr 2016; 13:25. [PMID: 27293386 PMCID: PMC4901467 DOI: 10.1186/s12970-016-0136-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Accepted: 06/01/2016] [Indexed: 11/23/2022] Open
Abstract
Background Increased ATP levels may enhance training-induced muscle accretion and fat loss, and caffeine is a known ergogenic aid. A novel supplement containing ancient peat and apple extracts has reported enhanced mitochondrial ATP production and it has been coupled with an extended-release caffeine. Therefore, the purpose of this investigation was to determine the effects of this supplement on body composition when used in conjunction with 12 weeks of resistance training. Methods Twenty-one resistance-trained subjects (27.2 ± 5.6y; 173.5 ± 5.7 cm; 82.8 ± 12.0 kg) completed this study. Subjects supplemented daily with either 1 serving of the supplement (TRT), which consisted of 150 mg ancient peat and apple extracts, 180 mg blend of caffeine anhydrous and pterostilbene-bound caffeine, and 38 mg B vitamins, or an equal-volume, visually-identical placebo (PLA) 45 min prior to training or at the same time of day on rest days. Supervised resistance training consisted of 8 weeks of daily undulating periodized training followed by a 2-week overreach and a 2-week taper phase. Body composition was assessed using DEXA and ultrasound at weeks 0, 4, 8, 10, and 12. Vital signs and blood markers were assessed at weeks 0, 8, and 12. Results Significant group x time (p < 0.05) interactions were present for cross-sectional area of the rectus femoris, which increased in TRT (+1.07 cm2) versus PLA (−0.08 cm2), as well as muscle thickness (TRT: +0.49 cm; PLA: +0.04 cm). A significant group x time (p < 0.05) interaction existed for creatinine (TRT: +0.00 mg/dL; PLA: +0.15 mg/dL) and estimated glomerular filtration rate (TRT: −0.70 mL/min/1.73; PLA: −14.6 mL/min/1.73), which remained within clinical ranges, but no other significant observations were observed. Conclusions Supplementation with a combination of extended-release caffeine and ancient peat and apple extracts may enhance resistance training-induced skeletal muscle hypertrophy without adversely affecting blood chemistry.
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Affiliation(s)
- Jordan M Joy
- Department of Nutrition and Food Sciences, Texas Woman's University, 401 AME Drive #7101, Denton, TX 76207 USA
| | - Roxanne M Vogel
- Department of Nutrition and Food Sciences, Texas Woman's University, 401 AME Drive #7101, Denton, TX 76207 USA
| | - Jordan R Moon
- American Public University System, School of Health Sciences, Charles Town, WV USA
| | - Paul H Falcone
- MusclePharm Sports Science Institute, MusclePharm Corp., Denver, CO USA
| | | | - Michael P Kim
- MusclePharm Sports Science Institute, MusclePharm Corp., Denver, CO USA
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12
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Hellhammer K, Zeus T, Verde PE, Veulemanns V, Kahlstadt L, Wolff G, Erkens R, Westenfeld R, Navarese EP, Merx MW, Rassaf T, Kelm M. Red cell distribution width in anemic patients undergoing transcatheter aortic valve implantation. World J Cardiol 2016; 8:220-230. [PMID: 26981217 PMCID: PMC4766272 DOI: 10.4330/wjc.v8.i2.220] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Revised: 10/03/2015] [Accepted: 11/25/2015] [Indexed: 02/06/2023] Open
Abstract
AIM: To determine the impact of red blood cell distribution width on outcome in anemic patients undergoing transcatheter aortic valve implantation (TAVI).
METHODS: In a retrospective single center cohort study we determined the impact of baseline red cell distribution width (RDW) and anemia on outcome in 376 patients with aortic stenosis undergoing TAVI. All patients were discussed in the institutional heart team and declined for surgical aortic valve replacement due to high operative risk. Collected data included patient characteristics, imaging findings, periprocedural in hospital data, laboratory results and follow up data. Blood samples for hematology and biochemistry analysis were taken from every patient before and at fixed intervals up to 72 h after TAVI including blood count and creatinine. Descriptive statistics were used for patient’s characteristics. Kaplan-Meier survival curves were used for time to event outcomes. A recursive partitioning regression and classification was used to investigate the association between potential risk factors and outcome variables.
RESULTS: Mean age in our study population was 81 ± 6.1 years. Anemia was prevalent in 63.6% (n = 239) of our patients. Age and creatinine were identified as risk factors for anemia. In our study population, anemia per se did influence 30-d mortality but did not predict longterm mortality. In contrast, a RDW > 14% showed to be highly predictable for a reduced short- and longterm survival in patients with aortic valve disease after TAVI procedure.
CONCLUSION: Age and kidney function determine the degree of anemia. The anisocytosis of red blood cells in anemic patients supplements prognostic information in addition to that derived from the WHO-based definition of anemia.
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Abstract
Functional components of the microcirculation provide oxygen and nutrients and remove waste products from the tissue beds of the body's organs. Shock states overwhelmingly stress functional capacity of the microcirculation, resulting in microcirculatory failure. In septic shock, inflammatory mediators contribute to hemodynamic instability. In nonseptic shock states, the microcirculation is better able to compensate for alterations in vascular resistance, cardiac output, and blood pressure. Therefore, global hemodynamic and oxygen delivery parameters are appropriate for assessing, monitoring, and guiding therapy in hypovolemic and cardiogenic shock but, alone, are inadequate for septic shock.
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Affiliation(s)
- Shannan K Hamlin
- Nursing Research and Evidence-Based Practice, Houston Methodist Hospital, MGJ 11-017, Houston, TX 77030, USA.
| | - C Lee Parmley
- Vanderbilt University Hospital, 1211 21st Avenue South, S3408 MCN, Nashville, TN 37212, USA; Department of Anesthesiology, Division of Critical Care, Vanderbilt University School of Medicine, 1211 21st Avenue South, S3408 MCN, Nashville, TN 37212, USA
| | - Sandra K Hanneman
- Center for Nursing Research, University of Texas Health Science Center at Houston School of Nursing, Room #594, 6901 Bertner Avenue, Houston, TX 77030, USA
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14
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Benedik PS, Hamlin SK. The physiologic role of erythrocytes in oxygen delivery and implications for blood storage. Crit Care Nurs Clin North Am 2016; 26:325-35. [PMID: 25169686 DOI: 10.1016/j.ccell.2014.04.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Erythrocytes are not just oxygen delivery devices but play an active metabolic role in modulating microvascular blood flow. Hemoglobin and red blood cell morphology change as local oxygen levels fall, eliciting the release of adenosine triphosphate and nitric oxide to initiate local vasodilation. Aged erythrocytes undergo physical and functional changes such that some of the red cell's most physiologically helpful attributes are diminished. This article reviews the functional anatomy and applied physiology of the erythrocyte and the microcirculation with an emphasis on how erythrocytes modulate microvascular function. The effects of cell storage on the metabolic functions of the erythrocyte are also briefly discussed.
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Affiliation(s)
- Penelope S Benedik
- Department of Acute and Continuing Care, School of Nursing, University of Texas Health Science Center at Houston, 6901 Bertner Street, SON 682, Houston, TX 77030, USA.
| | - Shannan K Hamlin
- Nursing Research and Evidence-Based Practice, Houston Methodist Hospital, 6565 Fannin, MGJ 11-017, Houston, TX 77030, USA
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Abstract
Aerobic exercise training leads to cardiovascular changes that markedly increase aerobic power and lead to improved endurance performance. The functionally most important adaptation is the improvement in maximal cardiac output which is the result of an enlargement in cardiac dimension, improved contractility, and an increase in blood volume, allowing for greater filling of the ventricles and a consequent larger stroke volume. In parallel with the greater maximal cardiac output, the perfusion capacity of the muscle is increased, permitting for greater oxygen delivery. To accommodate the higher aerobic demands and perfusion levels, arteries, arterioles, and capillaries adapt in structure and number. The diameters of the larger conduit and resistance arteries are increased minimizing resistance to flow as the cardiac output is distributed in the body and the wall thickness of the conduit and resistance arteries is reduced, a factor contributing to increased arterial compliance. Endurance training may also induce alterations in the vasodilator capacity, although such adaptations are more pronounced in individuals with reduced vascular function. The microvascular net increases in size within the muscle allowing for an improved capacity for oxygen extraction by the muscle through a greater area for diffusion, a shorter diffusion distance, and a longer mean transit time for the erythrocyte to pass through the smallest blood vessels. The present article addresses the effect of endurance training on systemic and peripheral cardiovascular adaptations with a focus on humans, but also covers animal data.
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Affiliation(s)
- Ylva Hellsten
- Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Michael Nyberg
- Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
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16
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Burnstock G. Blood cells: an historical account of the roles of purinergic signalling. Purinergic Signal 2015; 11:411-34. [PMID: 26260710 PMCID: PMC4648797 DOI: 10.1007/s11302-015-9462-7] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Accepted: 07/23/2015] [Indexed: 12/17/2022] Open
Abstract
The involvement of purinergic signalling in the physiology of erythrocytes, platelets and leukocytes was recognised early. The release of ATP and the expression of purinoceptors and ectonucleotidases on erythrocytes in health and disease are reviewed. The release of ATP and ADP from platelets and the expression and roles of P1, P2Y(1), P2Y(12) and P2X1 receptors on platelets are described. P2Y(1) and P2X(1) receptors mediate changes in platelet shape, while P2Y(12) receptors mediate platelet aggregation. The changes in the role of purinergic signalling in a variety of disease conditions are considered. The successful use of P2Y(12) receptor antagonists, such as clopidogrel and ticagrelor, for the treatment of thrombosis, myocardial infarction and stroke is discussed.
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Affiliation(s)
- Geoffrey Burnstock
- Autonomic Neuroscience Centre, University College Medical School, Rowland Hill Street, London, NW3 2PF, UK.
- Department of Pharmacology and Therapeutics, The University of Melbourne, Melbourne, Australia.
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Nyberg M, Gliemann L, Hellsten Y. Vascular function in health, hypertension, and diabetes: effect of physical activity on skeletal muscle microcirculation. Scand J Med Sci Sports 2015; 25 Suppl 4:60-73. [DOI: 10.1111/sms.12591] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/28/2015] [Indexed: 12/31/2022]
Affiliation(s)
- M. Nyberg
- Department of Nutrition, Exercise and Sports; University of Copenhagen; Copenhagen Denmark
| | - L. Gliemann
- Department of Nutrition, Exercise and Sports; University of Copenhagen; Copenhagen Denmark
| | - Y. Hellsten
- Department of Nutrition, Exercise and Sports; University of Copenhagen; Copenhagen Denmark
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A Putative Non-Canonical Ras-Like GTPase from P. falciparum: Chemical Properties and Characterization of the Protein. PLoS One 2015; 10:e0140994. [PMID: 26540393 PMCID: PMC4634863 DOI: 10.1371/journal.pone.0140994] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Accepted: 10/02/2015] [Indexed: 12/16/2022] Open
Abstract
During its development the malaria parasite P. falciparum has to adapt to various different environmental contexts. Key cellular mechanisms involving G-protein coupled signal transduction chains are assumed to act at these interfaces. Heterotrimeric G-proteins are absent in Plasmodium. We here describe the first cloning and expression of a putative, non-canonical Ras-like G protein (acronym PfG) from Plasmodium. PfG reveals an open reading frame of 2736 bp encoding a protein of 912 amino acids with a theoretical pI of 8.68 and a molecular weight of 108.57 kDa. Transcript levels and expression are significantly increased in the erythrocytic phase in particular during schizont and gametocyte formation. Most notably, PfG has GTP binding capacity and GTPase activity due to an EngA2 domain present in small Ras-like GTPases in a variety of Bacillus species and Mycobacteria. By contrast, plasmodial PfG is divergent from any human alpha-subunit. PfG was expressed in E. coli as a histidine-tagged fusion protein and was stable only for 3.5 hours. Purification was only possible under native conditions by Nickel-chelate chromatography and subsequent separation by Blue Native PAGE. Binding of a fluorescent GTP analogue BODIPY® FL guanosine 5’O-(thiotriphosphate) was determined by fluorescence emission. Mastoparan stimulated GTP binding in the presence of Mg2+. GTPase activity was determined colorimetrically. Activity expressed as absolute fluorescence was 50% higher for the human paralogue than the activity of the parasitic enzyme. The PfG protein is expressed in the erythrocytic stages and binds GTP after immunoprecipitation. Immunofluorescence using specific antiserum suggests that PfG localizes to the parasite cytosol. The current data suggest that the putitative, Ras-like G-protein might be involved in a non-canonical signaling pathway in Plasmodium. Research on the function of PfG with respect to pathogenesis and antimalarial chemotherapy is currently under way.
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Joy JM, Falcone PH, Vogel RM, Mosman MM, Kim MP, Moon JR. Supplementation with a proprietary blend of ancient peat and apple extract may improve body composition without affecting hematology in resistance-trained men. Appl Physiol Nutr Metab 2015; 40:1171-7. [PMID: 26489051 DOI: 10.1139/apnm-2015-0241] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Adenosine-5'-triphosphate (ATP) is primarily known as a cellular source of energy. Increased ATP levels may have the potential to enhance body composition. A novel, proprietary blend of ancient peat and apple extracts has been reported to increase ATP levels, potentially by enhancing mitochondrial ATP production. Therefore, the purpose of this investigation was to determine the supplement's effects on body composition when consumed during 12 weeks of resistance training. Twenty-five healthy, resistance-trained, male subjects (age, 27.7 ± 4.8 years; height, 176.0 ± 6.5 cm; body mass, 83.2 ± 12.1 kg) completed this study. Subjects supplemented once daily with either 1 serving (150 mg) of a proprietary blend of ancient peat and apple extracts (TRT) or placebo (PLA). Supervised resistance training consisted of 8 weeks of daily undulating periodized training followed by a 2-week overreach and a 2-week taper phase. Body composition was assessed using dual-energy X-ray absorptiometry and ultrasound at weeks 0, 4, 8, 10, and 12. Vital signs and blood markers were assessed at weeks 0, 8, and 12. Significant group × time (p < 0.05) interactions were present for ultrasound-determined cross-sectional area, which increased in TRT (+0.91 cm(2)) versus PLA (-0.08 cm(2)), as well as muscle thickness (TRT: +0.46; PLA: +0.04 cm). A significant group × time (p < 0.05) interaction existed for creatinine (TRT: +0.06; PLA: +0.15 mg/dL), triglycerides (TRT: +24.1; PLA: -20.2 mg/dL), and very-low-density lipoprotein (TRT: +4.9; PLA: -3.9 mg/dL), which remained within clinical ranges. Supplementation with a proprietary blend of ancient peat and apple extracts may enhance resistance training-induced skeletal muscle hypertrophy without affecting fat mass or blood chemistry in healthy males.
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Affiliation(s)
- Jordan M Joy
- a MusclePharm Sports Science Institute, MusclePharm Corp., Denver, CO 80239, USA
| | - Paul H Falcone
- a MusclePharm Sports Science Institute, MusclePharm Corp., Denver, CO 80239, USA
| | - Roxanne M Vogel
- a MusclePharm Sports Science Institute, MusclePharm Corp., Denver, CO 80239, USA
| | - Matt M Mosman
- a MusclePharm Sports Science Institute, MusclePharm Corp., Denver, CO 80239, USA
| | - Michael P Kim
- a MusclePharm Sports Science Institute, MusclePharm Corp., Denver, CO 80239, USA
| | - Jordan R Moon
- a MusclePharm Sports Science Institute, MusclePharm Corp., Denver, CO 80239, USA.,b Department of Sports Exercise Science, US Sports Academy, Daphne, AL 36526, USA
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20
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Abstract
PURPOSE OF REVIEW Oxygen (O2) delivery, the maintenance of which is fundamental to supporting those with critical illness, is a function of blood O2 content and flow. Here, we review red blood cell (RBC) physiology relevant to disordered O2 delivery in the critically ill. RECENT FINDINGS Flow (rather than content) is the focus of O2 delivery regulation. O2 content is relatively fixed, whereas flow fluctuates by several orders of magnitude. Thus, blood flow volume and distribution vary to maintain coupling between O2 delivery and demand. The trapping, processing and delivery of nitric oxide (NO) by RBCs has emerged as a conserved mechanism through which regional blood flow is linked to biochemical cues of perfusion sufficiency. We will review conventional RBC physiology that influences O2 delivery (O2 affinity & rheology) and introduce a new paradigm for O2 delivery homeostasis based on coordinated gas transport and vascular signaling by RBCs. SUMMARY By coordinating vascular signaling in a fashion that links O2 and NO flux, RBCs couple vessel caliber (and thus blood flow) to O2 need in tissue. Malfunction of this signaling system is implicated in a wide array of pathophysiologies and may be explanatory for the dysoxia frequently encountered in the critical care setting.
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21
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Swenson ER. New insights into carbonic anhydrase inhibition, vasodilation, and treatment of hypertensive-related diseases. Curr Hypertens Rep 2015; 16:467. [PMID: 25079851 DOI: 10.1007/s11906-014-0467-3] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Carbonic anhydrase (CA) and its inhibitors are relevant to many physiological processes and diseases. The enzyme is differentially expressed throughout the body, in concentration and subcellular location, and as 13 catalytically active isoforms. Blood vessels contain small amounts of CA, but the enzyme's role in vascular physiology and blood pressure regulation is uncertain. However, considerable recent evidence points to vasodilation by CA inhibitors. CA inhibition in vascular smooth muscle, endothelium, heart, blood cells, and nervous system could all contribute. It is equally plausible that other targets besides CA for all known CA inhibitors may account for their vascular effects. I will review this knowledge and important remaining gaps relating to treatment of hypertensive-related diseases with potent sulfonamide inhibitors, such as acetazolamide; but also the possibility that CA inhibition by thiazides and loop diuretics, although generally weaker, may have antihypertensive effects beyond their inhibition of renal sodium transporters.
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Affiliation(s)
- Erik R Swenson
- Department of Veterans Affairs, Pulmonary and Critical Care Medicine, VA Puget Sound Health Care System, University of Washington, 1660 South Columbian Way, Seattle, WA, USA,
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22
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Zeng NF, Ristenpart WD. Mechanical response of red blood cells entering a constriction. BIOMICROFLUIDICS 2014; 8:064123. [PMID: 25553197 PMCID: PMC4265125 DOI: 10.1063/1.4904058] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Accepted: 12/02/2014] [Indexed: 05/15/2023]
Abstract
Most work on the dynamic response of red blood cells (RBCs) to hydrodynamic stress has focused on linear velocity profiles. Relatively little experimental work has examined how individual RBCs respond to pressure driven flow in more complex geometries, such as the flow at the entrance of a capillary. Here, we establish the mechanical behaviors of healthy RBCs undergoing a sudden increase in shear stress at the entrance of a narrow constriction. We pumped RBCs through a constriction in a microfluidic device and used high speed video to visualize and track the flow behavior of more than 4400 RBCs. We show that approximately 85% of RBCs undergo one of four distinct modes of motion: stretching, twisting, tumbling, or rolling. Intriguingly, a plurality of cells (∼30%) exhibited twisting (rotation around the major axis parallel to the flow direction), a mechanical behavior that is not typically observed in linear velocity profiles. We present detailed statistical analyses on the dynamics of each motion and demonstrate that the behavior is highly sensitive to the location of the RBC within the channel. We further demonstrate that the observed tumbling, twisting, and rolling rotations can be rationalized qualitatively in terms of rigid body mechanics. The detailed experimental statistics presented here should serve as a useful resource for modeling of RBC behavior under physiologically important flow conditions.
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Affiliation(s)
- Nancy F Zeng
- Department of Chemical Engineering and Materials Science, University of California Davis , Davis, California 95616, USA
| | - William D Ristenpart
- Department of Chemical Engineering and Materials Science, University of California Davis , Davis, California 95616, USA
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23
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Jäger R, Roberts MD, Lowery RP, Joy JM, Cruthirds CL, Lockwood CM, Rathmacher JA, Purpura M, Wilson JM. Oral adenosine-5'-triphosphate (ATP) administration increases blood flow following exercise in animals and humans. J Int Soc Sports Nutr 2014; 11:28. [PMID: 25006331 PMCID: PMC4086998 DOI: 10.1186/1550-2783-11-28] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Accepted: 06/02/2014] [Indexed: 01/22/2023] Open
Abstract
INTRODUCTION Extracellular adenosine triphosphate (ATP) stimulates vasodilation by binding to endothelial ATP-selective P2Y2 receptors; a phenomenon, which is posited to be accelerated during exercise. Herein, we used a rat model to examine how different dosages of acute oral ATP administration affected the femoral blood flow response prior to, during, and after an exercise bout. In addition, we performed a single dose chronic administration pilot study in resistance trained athletes. METHODS ANIMAL STUDY Male Wistar rats were gavage-fed the body surface area, species adjusted human equivalent dose (HED) of either 100 mg (n=4), 400 mg (n=4), 1,000 mg (n=5) or 1,600 mg (n=5) of oral ATP as a disodium salt (Peak ATP®, TSI, Missoula, MT). Rats that were not gavage-fed were used as controls (CTL, n=5). Blood flow was monitored continuously: a) 60 min prior to, b) during and c) 90 min following an electrically-evoked leg-kicking exercise. Human Study: In a pilot study, 12 college-aged resistance-trained subjects were given 400 mg of ATP (Peak ATP®, TSI, Missoula, MT) daily for 12 weeks, and prior to an acute arm exercise bout at weeks 1, 4, 8, and 12. Ultrasonography-determined volumetric blood flow and vessel dilation in the brachial artery was measured at rest, at rest 30 minutes after supplementation, and then at 0, 3, and 6 minutes after the exercise. RESULTS ANIMAL STUDY Rats fed 1,000 mg HED demonstrated significantly greater recovery blood flow (p < 0.01) and total blood flow AUC values (p < 0.05) compared to CTL rats. Specifically, blood flow was elevated in rats fed 1,000 mg HED versus CTL rats at 20 to 90 min post exercise when examining 10-min blood flow intervals (p < 0.05). When examining within-group differences relative to baseline values, rats fed the 1,000 mg and 1,600 mg HED exhibited the most robust increases in blood flow during exercise and into the recovery period. Human study: At weeks 1, 8, and 12, ATP supplementation significantly increased blood flow, along with significant elevations in brachial dilation. CONCLUSIONS Oral ATP administration can increase post-exercise blood flow, and may be particularly effective during exercise recovery.
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Affiliation(s)
- Ralf Jäger
- Increnovo LLC, 2138 E Lafayette Pl, Milwaukee, WI 53202, USA
| | - Michael D Roberts
- School of Kinesiology, Molecular and Applied Sciences Laboratory, Auburn University, Auburn, AL 36849, USA
| | - Ryan P Lowery
- Department of Health Sciences and Human Performance, The University of Tampa, 318 N Boulevard, Tampa, FL 33606, USA
| | - Jordan M Joy
- Department of Health Sciences and Human Performance, The University of Tampa, 318 N Boulevard, Tampa, FL 33606, USA
| | - Clayton L Cruthirds
- Department of Biomedical Sciences, College of Veterinary Medicine, University of Missouri-Columbia, 1600 Rollins, Columbia, MO 65211, USA
| | | | - John A Rathmacher
- Metabolic Technologies Inc., 2711 S Loop Dr, Suite 4400, Ames, IA 50010, USA ; Department of Animal Sciences, Iowa State University, Ames, IA, 50011, USA
| | - Martin Purpura
- Increnovo LLC, 2138 E Lafayette Pl, Milwaukee, WI 53202, USA
| | - Jacob M Wilson
- Department of Health Sciences and Human Performance, The University of Tampa, 318 N Boulevard, Tampa, FL 33606, USA
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Richards JP, Stephenson AH, Ellsworth ML, Sprague RS. Synergistic effects of C-peptide and insulin on low O2-induced ATP release from human erythrocytes. Am J Physiol Regul Integr Comp Physiol 2013; 305:R1331-6. [PMID: 24089376 DOI: 10.1152/ajpregu.00341.2013] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Erythrocytes participate in the matching of oxygen (O2) delivery with local need in skeletal muscle via the release of O2 and the vasodilator, ATP. It was reported that a concentration of insulin found in humans with insulin resistance inhibits low O2-induced ATP release. However, in vivo, insulin is coreleased with connecting peptide (C-peptide) at equimolar concentrations, but because of the shorter insulin half-life, the peptides circulate at ratios of C-peptide to insulin ranging from 1:1 to 6:1. Here, we investigate the hypothesis that C-peptide and insulin work synergistically to maintain low O2-induced ATP release from human erythrocytes. Using a thin-film tonometer to alter O2 tension, we determined that either C-peptide or insulin alone inhibits low O2-induced ATP release in a concentration-dependent manner; however, coadministration of the peptides at a 1:1 ratio does not (n = 5; P < 0.05). Because this ratio of C-peptide to insulin is not present in vivo for extended periods, we also investigated the effect of additional physiological ratios on ATP release. In the presence of insulin concentrations that would be found in fasting humans (0.05 nM), C-peptide to insulin ratios of 4:1 and 6:1 did not adversely affect low O2-induced ATP release. However, at a concentration of insulin found in the peripheral circulation of humans under postprandial conditions (0.5 nM), a ratio of C-peptide to insulin of 6:1 inhibited low O2-induced ATP release (n = 5). These findings demonstrate a heretofore unrecognized synergism between C-peptide and insulin that could have physiological importance in the regulation of perfusion distribution in skeletal muscle.
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Affiliation(s)
- Jennifer P Richards
- Department of Pharmacological and Physiological Science, Saint Louis University, St. Louis, Missouri
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25
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Wilson JM, Joy JM, Lowery RP, Roberts MD, Lockwood CM, Manninen AH, Fuller JC, De Souza EO, Baier SM, Wilson SM, Rathmacher JA. Effects of oral adenosine-5'-triphosphate supplementation on athletic performance, skeletal muscle hypertrophy and recovery in resistance-trained men. Nutr Metab (Lond) 2013; 10:57. [PMID: 24330670 PMCID: PMC3849389 DOI: 10.1186/1743-7075-10-57] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2013] [Accepted: 09/13/2013] [Indexed: 11/23/2022] Open
Abstract
Background Currently, there is a lack of studies examining the effects of adenosine-5′-triphosphate (ATP) supplementation utilizing a long-term, periodized resistance-training program (RT) in resistance-trained populations. Therefore, we investigated the effects of 12 weeks of 400 mg per day of oral ATP on muscular adaptations in trained individuals. We also sought to determine the effects of ATP on muscle protein breakdown, cortisol, and performance during an overreaching cycle. Methods The study was a 3-phase randomized, double-blind, and placebo- and diet-controlled intervention. Phase 1 was a periodized resistance-training program. Phase 2 consisted of a two week overreaching cycle in which volume and frequency were increased followed by a 2-week taper (Phase 3). Muscle mass, strength, and power were examined at weeks 0, 4, 8, and 12 to assess the chronic effects of ATP; assessment performance variables also occurred at the end of weeks 9 and 10, corresponding to the mid and endpoints of the overreaching cycle. Results There were time (p < 0.001), and group x time effects for increased total body strength (+55.3 ± 6.0 kg ATP vs. + 22.4 ± 7.1 kg placebo, p < 0.001); increased vertical jump power (+ 796 ± 75 ATP vs. 614 ± 52 watts placebo, p < 0.001); and greater ultrasound determined muscle thickness (+4.9 ± 1.0 ATP vs. (2.5 ± 0.6 mm placebo, p < 0.02) with ATP supplementation. During the overreaching cycle, there were group x time effects for strength and power, which decreased to a greater extent in the placebo group. Protein breakdown was also lower in the ATP group. Conclusions Our results suggest oral ATP supplementation may enhance muscular adaptations following 12-weeks of resistance training, and prevent decrements in performance following overreaching. No statistically or clinically significant changes in blood chemistry or hematology were observed. Trial registration ClinicalTrials.gov NCT01508338
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Abstract
The pancreas is an organ with a central role in nutrient breakdown, nutrient sensing and release of hormones regulating whole body nutrient homeostasis. In diabetes mellitus, the balance is broken-cells can be starving in the midst of plenty. There are indications that the incidence of diabetes type 1 and 2, and possibly pancreatogenic diabetes, is rising globally. Events leading to insulin secretion and action are complex, but there is emerging evidence that intracellular nucleotides and nucleotides are not only important as intracellular energy molecules but also as extracellular signalling molecules in purinergic signalling cascades. This signalling takes place at the level of the pancreas, where the close apposition of various cells-endocrine, exocrine, stromal and immune cells-contributes to the integrated function. Following an introduction to diabetes, the pancreas and purinergic signalling, we will focus on the role of purinergic signalling and its changes associated with diabetes in the pancreas and selected tissues/organ systems affected by hyperglycaemia and other stress molecules of diabetes. Since this is the first review of this kind, a comprehensive historical angle is taken, and common and divergent roles of receptors for nucleotides and nucleosides in different organ systems will be given. This integrated picture will aid our understanding of the challenges of the potential and currently used drugs targeted to specific organ/cells or disorders associated with diabetes.
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Affiliation(s)
- Geoffrey Burnstock
- Autonomic Neuroscience Centre, University College Medical School, Rowland Hill Street, London, NW3 2PF UK
- Department of Pharmacology, Melbourne University, Melbourne, Australia
| | - Ivana Novak
- Molecular and Integrative Physiology, Department of Biology, University of Copenhagen, August Krogh Building, Universitetsparken 13, 2100 Copenhagen Ø, Denmark
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Leal Denis MF, Incicco JJ, Espelt MV, Verstraeten SV, Pignataro OP, Lazarowski ER, Schwarzbaum PJ. Kinetics of extracellular ATP in mastoparan 7-activated human erythrocytes. Biochim Biophys Acta Gen Subj 2013; 1830:4692-707. [PMID: 23742824 DOI: 10.1016/j.bbagen.2013.05.033] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Revised: 04/24/2013] [Accepted: 05/20/2013] [Indexed: 01/26/2023]
Abstract
BACKGROUND The peptide mastoparan 7 (MST7) stimulated ATP release in human erythrocytes. We explored intra- and extracellular processes governing the time-dependent accumulation of extracellular ATP (i.e., ATPe kinetics). METHODS Human erythrocytes were treated with MST7 in the presence or absence of two blockers of pannexin 1. ATPe concentration was monitored by luciferin-luciferase based real-time luminometry. RESULTS Exposure of human erythrocytes to MST7 led to an acute increase in [ATPe], followed by a slower increase phase. ATPe kinetics reflected a strong activation of ATP efflux and a low rate of ATPe hydrolysis by ectoATPase activity. Enhancement of [ATPe] by MST7 required adhesion of erythrocytes to poly-D-lysin-coated coverslips, and correlated with a 31% increase of cAMP and 10% cell swelling. However, when MST7 was dissolved in a hyperosmotic medium to block cell swelling, ATPe accumulation was inhibited by 49%. Erythrocytes pre-exposure to 10μM of either carbenoxolone or probenecid, two blockers of pannexin 1, exhibited a partial reduction of ATP efflux. Erythrocytes from pannexin 1 knockout mice exhibited similar ATPe kinetics as those of wild type mice erythrocytes exposed to pannexin 1 blockers. CONCLUSIONS MST7 induced release of ATP required either cell adhesion or strong activation of cAMP synthesis. Part of this release required cell swelling. Kinetic analysis and a data driven model suggested that ATP efflux is mediated by two ATP conduits displaying different kinetics, with one conduit being fully blocked by pannexin 1 blockers. GENERAL SIGNIFICANCE Kinetic analysis of extracellular ATP accumulation from human erythrocytes and potential effects on microcirculation.
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28
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Proctor DN, Moore DJ. Lifelong physical activity and blood flow to active muscles: sufficient supply to meet the demand. J Physiol 2013. [PMID: 23204098 DOI: 10.1113/jphysiol.2012.245183] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Affiliation(s)
- David N Proctor
- Department of Kinesiology, 105 Noll Laboratory, The Pennsylvania State University, University Park, PA 16802, USA.
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Liu Y, Sun CW, Honavar J, Townes T, Patel RP. Role of the b93cys, ATP and adenosine in red cell dependent hypoxic vasorelaxation. INTERNATIONAL JOURNAL OF PHYSIOLOGY, PATHOPHYSIOLOGY AND PHARMACOLOGY 2013; 5:21-31. [PMID: 23525514 PMCID: PMC3601459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 01/03/2013] [Accepted: 02/19/2013] [Indexed: 06/02/2023]
Abstract
Two of the proposed mechanisms by which red blood cells (RBC) mediate hypoxic vasorelaxation by coupling hemoglobin deoxygenation to the activation of nitric oxide signaling involve ATP-release from RBC and S-nitrosohemoglobin (b93C(SNO)Hb) dependent bioactivity. However, different studies have reached opposite conclusions regarding the aforementioned mechanisms. Using isolated vessels, hypoxic vasorelaxation induced by human, C57BL/6 or mouse RBC which exclusively express either native human hemoglobin (HbC93) or human hemoglobin in which the conserved b93cys was replaced with Ala (HbC93A) were compared. All RBCs stimulated hypoxic vasodilation to similar extents suggesting the b93cys is not required for this RBC-mediated function. Hypoxic vasorelaxation was inhibited by co-incubation of ATP-pathway blockers including L-NAME (eNOS inhibitor) and Apyrase. Moreover, we tested if modulation of adenosine-dependent signaling affected RBC-dependent vasorelaxation using pan- or subtype specific adenosine receptor blockers, or adenosine deaminase (ADA). Interestingly, ADA and adenosine A2 receptor blockade, but not A1 receptor blockade, inhibited HbC93, HbC93A dependent hypoxic vasorelaxation. Equivalent results were obtained with human RBC. These data suggest that using isolated vessels, RBC do not require the presence of the b93cys to elicit hypoxic vasorelaxation and mediate this response via ATP- and a novel adenosine-dependent mechanism.
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Affiliation(s)
- Yanping Liu
- Departments of Pathology and Center for Free Radical Biology, University of Alabama at Birmingham Birmingham AL 35294, USA
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30
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Zuo L, Li Q, Sun B, Xu Z, Ge Z. Cilostazol promotes mitochondrial biogenesis in human umbilical vein endothelial cells through activating the expression of PGC-1α. Biochem Biophys Res Commun 2013; 433:52-7. [PMID: 23485471 DOI: 10.1016/j.bbrc.2013.02.068] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2013] [Accepted: 02/19/2013] [Indexed: 11/30/2022]
Abstract
Mitochondrial dysfunction is frequently observed in vascular diseases. Cilostazol is a drug approved by the US Food and Drug Administration for the treatment of intermittent claudication. Cilostazol increases intracellular cyclic adenosine monophosphate (cAMP) levels through inhibition of type III phosphodiesterase. The effects of cilostazol in mitochondrial biogenesis in human umbilical vein endothelial cells (HUVECs) were investigated in this study. Cilostazol treated HUVECs displayed increased levels of ATP, mitochondrial DNA/nuclear DNA ratio, expressions of cytochrome B, and mitochondrial mass, suggesting an enhanced mitochondrial biogenesis induced by cilostazol. The promoted mitochondrial biogenesis could be abolished by Protein kinase A (PKA) specific inhibitor H-89, implying that PKA pathway played a critical role in increased mitochondrial biogenesis after cilostazol treatment. Indeed, expression levels of peroxisome proliferator activator receptor gamma-coactivator 1α (PGC-1α), NRF 1 and mitochondrial transcription factor A (TFAM) were significantly increased in HUVECs after incubation with cilostazol at both mRNA levels and protein levels. Importantly, knockdown of PGC-1α could abolish cilostazol-induced mitochondrial biogenesis. Enhanced expression of p-CREB and PGC-1α induced by cilostazol could be inhibited by H-89. Moreover, the increased expression of PGC-1α induced by cilostazol could be inhibited by downregulation of CREB using CREB siRNA at both mRNA and protein levels. All the results indicated that cilostazol promoted mitochondrial biogenesis through activating the expression of PGC-1α in HUVECs, which was mediated by PKA/CREB pathway.
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Affiliation(s)
- Luning Zuo
- Shandong University, 44# Wenhua Xi Road, Jinan, Shandong 250012, PR China
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31
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Ishida K, Matsumoto T, Taguchi K, Kamata K, Kobayashi T. Mechanisms underlying reduced P2Y(1) -receptor-mediated relaxation in superior mesenteric arteries from long-term streptozotocin-induced diabetic rats. Acta Physiol (Oxf) 2013; 207:130-41. [PMID: 22759594 DOI: 10.1111/j.1748-1716.2012.02469.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2011] [Revised: 05/29/2012] [Accepted: 06/25/2012] [Indexed: 12/20/2022]
Abstract
AIM Extracellular nucleotides activate cell-surface purinergic (P2) receptors, contribute to the local regulation of vascular tone and play important roles in pathophysiological states. However, little is known about the vasodilator effects of P2Y(1) -receptor activation in diabetic states. We hypothesized that in a model of established type 1 diabetes, long-term streptozotocin (STZ)-induced diabetic rats, the arterial relaxation elicited by a P2Y(1) -receptor agonist would be impaired. METHODS Relaxations to adenosine 5'-diphosphate sodium salt (ADP), 2-MeSADP (selective P2Y(1) -receptor agonist) and adenosine 5'-triphosphate disodium salt (ATP) were examined in superior mesenteric artery rings from long-term STZ-induced diabetic rats (at 50-57 weeks after STZ injection). ADP-stimulated nitric oxide (NO) production in the superior mesenteric artery was assessed by measuring the levels of NO metabolites. Mesenteric artery expressions of P2Y(1) receptor, and ADP-stimulated levels of phosphorylated endothelial NO synthase (eNOS) (at Ser(1177) and at Thr(495) ) and eNOS were detected by Western blotting. RESULTS Arteries from diabetic rats exhibited (vs. those from age-matched control rats): (i) reduced ADP-induced relaxation, which was partly or completely inhibited by endothelial denudation, by NOS inhibitor treatment and by a selective P2Y(1) -receptor antagonist, (ii) reduced 2-MeSADP-induced relaxation, (iii) reduced ADP-stimulated release of NO metabolites and (iv) impaired ADP-induced stimulation of eNOS activity (as evidenced by reduced the fold increase in eNOS phosphorylation at Ser(1177) with no difference in fold increase in eNOS phosphorylation at Thr(495) ). The protein expression of P2Y(1) receptor did not differ between diabetic and control arteries. CONCLUSIONS These results suggest that P2Y(1) -receptor-mediated vasodilatation is impaired in superior mesenteric arteries from long-term type 1 diabetic rats. This impairment is because of reduced P2Y(1) -receptor-mediated NO signalling, rather than to reduced P2Y(1) -receptor expression.
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Affiliation(s)
- K. Ishida
- Department of Physiology and Morphology, Institute of Medicinal Chemistry; Hoshi University; Shinagawa-ku; Tokyo; Japan
| | - T. Matsumoto
- Department of Physiology and Morphology, Institute of Medicinal Chemistry; Hoshi University; Shinagawa-ku; Tokyo; Japan
| | - K. Taguchi
- Department of Physiology and Morphology, Institute of Medicinal Chemistry; Hoshi University; Shinagawa-ku; Tokyo; Japan
| | - K. Kamata
- Department of Physiology and Morphology, Institute of Medicinal Chemistry; Hoshi University; Shinagawa-ku; Tokyo; Japan
| | - T. Kobayashi
- Department of Physiology and Morphology, Institute of Medicinal Chemistry; Hoshi University; Shinagawa-ku; Tokyo; Japan
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32
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Sandilos JK, Bayliss DA. Physiological mechanisms for the modulation of pannexin 1 channel activity. J Physiol 2012; 590:6257-66. [PMID: 23070703 DOI: 10.1113/jphysiol.2012.240911] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
It is widely recognized that ATP, along with other nucleotides, subserves important intercellular signalling processes. Among various nucleotide release mechanisms, the relatively recently identified pannexin 1 (Panx1) channel is gaining prominence by virtue of its ability to support nucleotide permeation and release in a variety of different tissues. Here, we review recent advances in our understanding of the factors that control Panx1 channel activity. By using electrophysiological and biochemical approaches, diverse mechanisms that dynamically regulate Panx1 channel function have been identified in various settings; these include, among others, activation by caspase-mediated channel cleavage in apoptotic immune cells, by G protein-coupled receptors in vascular smooth muscle, by low oxygen tension in erythrocytes and neurons, by high extracellular K(+) in various cell types and by stretch/strain in airway epithelia. Delineating the distinct mechanisms of Panx1 modulation that prevail in different physiological contexts provides the possibility that these channels, and ATP release, could ultimately be targeted in a context-dependent manner.
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Affiliation(s)
- Joanna K Sandilos
- Department of Pharmacology, University of Virginia, Charlottesville, VA, USA.
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Rathmacher JA, Fuller JC, Baier SM, Abumrad NN, Angus HF, Sharp RL. Adenosine-5'-triphosphate (ATP) supplementation improves low peak muscle torque and torque fatigue during repeated high intensity exercise sets. J Int Soc Sports Nutr 2012; 9:48. [PMID: 23046855 PMCID: PMC3483284 DOI: 10.1186/1550-2783-9-48] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Accepted: 10/03/2012] [Indexed: 01/08/2023] Open
Abstract
Background Intracellular concentrations of adenosine-5’-triphosphate (ATP) are many times greater than extracellular concentrations (1–10 mM versus 10–100 nM, respectively) and cellular release of ATP is tightly controlled. Transient rises in extracellular ATP and its metabolite adenosine have important signaling roles; and acting through purinergic receptors, can increase blood flow and oxygenation of tissues; and act as neurotransmitters. Increased blood flow not only increases substrate availability but may also aid in recovery through removal of metabolic waste products allowing muscles to accomplish more work with less fatigue. The objective of the present study was to determine if supplemental ATP would improve muscle torque, power, work, or fatigue during repeated bouts of high intensity resistance exercise. Methods Sixteen participants (8 male and 8 female; ages: 21–34 years) were enrolled in a double-blinded, placebo-controlled study using a crossover design. The participants received either supplemental ATP (400 mg/d divided into 2 daily doses) or placebo for 15 d. After an overnight fast, participants underwent strength and fatigue testing, consisting of 3 sets of 50 maximal knee extensions performed on a Biodex® leg dynamometer. Results No differences were detected in high peak torque, power, or total work with ATP supplementation; however, low peak torque in set 2 was significantly improved (p < 0.01). Additionally, in set 3, a trend was detected for less torque fatigue with ATP supplementation (p < 0.10). Conclusions Supplementation with 400 mg ATP/d for 15 days tended to reduce muscle fatigue and improved a participant’s ability to maintain a higher force output at the end of an exhaustive exercise bout.
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Affiliation(s)
- John A Rathmacher
- Department of Animal Science, Iowa State University, Ames, IA, 50010, USA.
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Chilian WM, Yin L, Ohanyan VA. Mysteries in the local control of blood flow: a physiological "whodunit" involving red cell release of ATP? Circ Res 2012; 111:156-7. [PMID: 22773423 DOI: 10.1161/circresaha.112.273060] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Goldman D, Fraser GM, Ellis CG, Sprague RS, Ellsworth ML, Stephenson AH. Toward a multiscale description of microvascular flow regulation: o(2)-dependent release of ATP from human erythrocytes and the distribution of ATP in capillary networks. Front Physiol 2012; 3:246. [PMID: 22934004 PMCID: PMC3429024 DOI: 10.3389/fphys.2012.00246] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2012] [Accepted: 06/15/2012] [Indexed: 11/27/2022] Open
Abstract
Integration of the numerous mechanisms that have been suggested to contribute to optimization of O2 supply to meet O2 need in skeletal muscle requires a systems biology approach which permits quantification of these physiological processes over a wide range of length scales. Here we describe two individual computational models based on in vivo and in vitro studies which, when incorporated into a single robust multiscale model, will provide information on the role of erythrocyte-released ATP in perfusion distribution in skeletal muscle under both physiological and pathophysiological conditions. Healthy human erythrocytes exposed to low O2 tension release ATP via a well characterized signaling pathway requiring activation of the G-protein, Gi, and adenylyl cyclase leading to increases in cAMP. This cAMP then activates PKA and subsequently CFTR culminating in ATP release via pannexin 1. A critical control point in this pathway is the level of cAMP which is regulated by pathway-specific phosphodiesterases. Using time constants (~100 ms) that are consistent with measured erythrocyte ATP release, we have constructed a dynamic model of this pathway. The model predicts levels of ATP release consistent with measurements obtained over a wide range of hemoglobin O2 saturations (sO2). The model further predicts how insulin, at concentrations found in pre-diabetes, enhances the activity of PDE3 and reduces intracellular cAMP levels leading to decreased low O2-induced ATP release from erythrocytes. The second model, which couples O2 and ATP transport in capillary networks, shows how intravascular ATP and the resulting conducted vasodilation are affected by local sO2, convection and ATP degradation. This model also predicts network-level effects of decreased ATP release resulting from elevated insulin levels. Taken together, these models lay the groundwork for investigating the systems biology of the regulation of microvascular perfusion distribution by erythrocyte-derived ATP.
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Affiliation(s)
- Daniel Goldman
- Department of Medical Biophysics, University of Western Ontario London, ON, Canada
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36
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Owusu BY, Stapley R, Patel RP. Nitric oxide formation versus scavenging: the red blood cell balancing act. J Physiol 2012; 590:4993-5000. [PMID: 22687616 DOI: 10.1113/jphysiol.2012.234906] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Nitric oxide (NO) is a key modulator of vascular homeostasis controlling critical functions related to blood flow, respiration, cell death and proliferation, and protecting the vasculature from pro-inflammatory and coagulative stresses. Inhibition of NO formation, and/or diversion of NO away from its physiological signalling targets lead to dysregulated NO bioavailability, a hallmark of numerous vascular and pulmonary diseases. Current concepts suggest that the balance between NO formation and NO scavenging is critical in disease development, with the corollary being that redressing the balance offers a target for therapeutic intervention. Evidence presented over the last two decades has seen red blood cells (RBCs) and haemoglobin specifically emerge as prominent effectors in this paradigm. In this symposium review article, we discuss recent insights into the mechanisms by which RBCs may modulate the balance between NO-formation and inhibition. We discuss how these mechanisms may become dysfunctional to cause disease, highlight key questions that remain, and discuss the potential impact of these insights on therapeutic opportunities.
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Affiliation(s)
- Benjamin Y Owusu
- Department of Pathology, University of Alabama at Birmingham, 901 19th Street South, BMRII 532, Birmingham, AL 35294, USA
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Fähling M, Persson PB. Oxygen sensing, uptake, delivery, consumption and related disorders. Acta Physiol (Oxf) 2012; 205:191-3. [PMID: 22520692 DOI: 10.1111/j.1748-1716.2012.02432.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- M. Fähling
- Institute of Vegetative Physiology; Charité-Universitaetsmedizin Berlin; Berlin; Germany
| | - P. B. Persson
- Institute of Vegetative Physiology; Charité-Universitaetsmedizin Berlin; Berlin; Germany
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Ellsworth ML, Sprague RS. Regulation of blood flow distribution in skeletal muscle: role of erythrocyte-released ATP. J Physiol 2012; 590:4985-91. [PMID: 22586223 DOI: 10.1113/jphysiol.2012.233106] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
The maintenance of adequate tissue O(2) levels in skeletal muscle is vital for normal physiology and requires a well regulated and appropriately distributed convective O(2) supply. Inherent in this fundamental physiological process is the requirement for a mechanism which both senses tissue O(2) need and locally adjusts flow to appropriately meet that need. Over the past several years we and others have suggested that, in skeletal muscle, O(2) carrying erythrocytes participate in the regulation of total blood flow and its distribution by releasing ATP. Importantly, the release of this vasoactive molecule must be both rapid and well controlled if it is to serve an important physiological role. Here we provide insights into three distinct regulated signalling pathways within the erythrocyte that are activated by exposure to reduced O(2) tension or in response to binding of agonists to the prostacyclin or β-adrenergic receptors. Although much has been learned about the role of the erythrocyte in perfusion of skeletal muscle, much remains to be understood. However, what is clear is that the long established passive carrier of O(2) also contributes to the regulation of the distribution of microvascular perfusion in skeletal muscle by virtue of its capacity to release ATP.
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Affiliation(s)
- Mary L Ellsworth
- Department of Pharmacological and Physiological Science, Saint Louis University School of Medicine, 1402 South Grand Boulevard, St Louis, MO 63104, USA.
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Purinoceptor signaling in malaria-infected erythrocytes. Microbes Infect 2012; 14:779-86. [PMID: 22580091 DOI: 10.1016/j.micinf.2012.04.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2012] [Revised: 04/13/2012] [Accepted: 04/13/2012] [Indexed: 01/25/2023]
Abstract
Human erythrocytes are endowed with ATP release pathways and metabotropic and ionotropic purinoceptors. This review summarizes the pivotal function of purinergic signaling in erythrocyte control of vascular tone, in hemolytic septicemia, and in malaria. In malaria, the intraerythrocytic parasite exploits the purinergic signaling of its host to adapt the erythrocyte to its requirements.
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40
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Losing control over adenosine 5'-triphosphate release: implications for the red blood cell storage lesion. Crit Care Med 2011; 39:2573-4. [PMID: 22005234 DOI: 10.1097/ccm.0b013e31822a55fa] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Sprague RS, Bowles EA, Achilleus D, Stephenson AH, Ellis CG, Ellsworth ML. A selective phosphodiesterase 3 inhibitor rescues low PO2-induced ATP release from erythrocytes of humans with type 2 diabetes: implication for vascular control. Am J Physiol Heart Circ Physiol 2011; 301:H2466-72. [PMID: 21963837 DOI: 10.1152/ajpheart.00729.2011] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Erythrocytes, via release of ATP in areas of low oxygen (O(2)) tension, are components of a regulatory system for the distribution of perfusion in skeletal muscle ensuring optimal O(2) delivery to meet tissue needs. In type 2 diabetes (DM2), there are defects in O(2) supply to muscle as well as a failure of erythrocytes to release ATP. The goal of this study was to ascertain if a phosphodiesterase 3 (PDE3) inhibitor, cilostazol, would rescue low O(2)-induced ATP release from DM2 erythrocytes and, thereby, enable these cells to dilate isolated erythrocyte-perfused skeletal muscle arterioles exposed to decreased extraluminal O(2). Erythrocytes were obtained from healthy humans (HH; n = 12) and humans with DM2 (n = 17). We determined that 1) PDE3B is similarly expressed in both groups, 2) mastoparan 7 (G(i) activation) stimulates increases in cAMP in HH but not in DM2 erythrocytes, and 3) pretreatment of DM2 erythrocytes with cilostazol resulted in mastoparan 7-induced increases in cAMP not different from those in HH cells. Most importantly, cilostazol restored the ability of DM2 erythrocytes to release ATP in response to low O(2). In contrast with perfusion with HH erythrocytes, isolated hamster retractor muscle arterioles perfused with DM2 erythrocytes constricted in response to low extraluminal PO(2). However, in the presence of cilostazol (100 μM), DM2 erythrocytes induced vessel dilation not different from that seen with HH erythrocytes. Thus rescue of low O(2)-induced ATP release from DM2 erythrocytes by cilostazol restored the ability of erythrocytes to participate in the regulation of perfusion distribution in skeletal muscle.
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Affiliation(s)
- Randy S Sprague
- Department of Pharmacological and Physiological Science, Saint Louis University School of Medicine, Missouri 63104, USA.
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42
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Bravo DM, Gimenes AC, Nascimento RB, Ferreira EVM, Siqueira ACB, Meda EDS, Neder JA, Nery LE. Skeletal muscle reoxygenation after high-intensity exercise in mitochondrial myopathy. Eur J Appl Physiol 2011; 112:1763-71. [PMID: 21898145 DOI: 10.1007/s00421-011-2136-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2010] [Accepted: 08/16/2011] [Indexed: 11/29/2022]
Abstract
This study addressed whether O(2) delivery during recovery from high-intensity, supra-gas exchange threshold exercise would be matched to O(2) utilization at the microvascular level in patients with mitochondrial myopathy (MM). Off-exercise kinetics of (1) pulmonary O(2) uptake VO(2P) (2) an index of fractional O(2) extraction by near-infrared spectroscopy (Δ[deoxy-Hb + Mb]) in the vastus lateralis and (3) cardiac output (Q'(T)) by impedance cardiography were assessed in 12 patients with biopsy-proven MM (chronic progressive external ophthalmoplegia) and 12 age- and gender-matched controls. Kinetics of VO(2P) were significantly slower in patients than controls (τ = 53.8 ± 16.5 vs. 38.8 ± 7.6 s, respectively; p < 0.05). Q'(T), however, declined at similar rates (τ = 64.7 ± 18.8 vs. 73.0 ± 21.6 s; p > 0.05) being typically slower than [Formula: see text] in both groups. Importantly, Δ[deoxy-Hb + Mb] dynamics (MRT) were equal to, or faster than, τVO(2P) in patients and controls, respectively. In fact, there were no between-group differences in τVO(2P)MRTΔ[deoxy-Hb + Mb] (1.1 ± 0.4 vs. 1.0 ± 0.2, p > 0.05) thereby indicating similar rates of microvascular O(2) delivery. These data indicate that the slower rate of recovery of muscle metabolism after high-intensity exercise is not related to impaired microvascular O(2) delivery in patients with MM. This phenomenon, therefore, seems to reflect the intra-myocyte abnormalities that characterize this patient population.
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Affiliation(s)
- Daniela M Bravo
- Division of Respiratory Medicine, Department of Medicine, Pulmonary Function and Clinical Exercise Physiology Unit, Federal University of Sao Paulo, Paulista School of Medicine, Rua Botucatu, 740 3rd floor, Vila Clementino, Sao Paulo, Sao Paulo CEP 04023-062, Brazil.
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43
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Weinberg JA, Barnum SR, Patel RP. Red blood cell age and potentiation of transfusion-related pathology in trauma patients. Transfusion 2011; 51:867-73. [PMID: 21496048 DOI: 10.1111/j.1537-2995.2011.03098.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The specific negative clinical manifestations associated with the transfusion of stored red blood cells (RBCs) and the corresponding mechanisms responsible for such phenomena remain poorly defined. Our recent studies document that leukoreduced older RBC units potentiate transfusion-related toxicity in trauma patients. It is our hypothesis that the transfusion of relatively older blood impedes microvascular perfusion. The central mechanisms proposed to mediate this microcirculatory alteration include: 1) the loss of RBC-dependent control of nitric oxide-mediated homeostasis concerning vasodilation and 2) immune cell and complement activation. In this review, we outline the background for our hypothesis and detail our current investigations toward the understanding of this pathophysiology.
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Affiliation(s)
- Jordan A Weinberg
- Department of Surgery, University of Tennessee Health Science Center, 910 Madison Avenue, #224, Memphis, TN 38103, USA.
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