scholarly journals Adenosine: a physiological modulator of superoxide anion generation by human neutrophils.

1983 ◽  
Vol 158 (4) ◽  
pp. 1160-1177 ◽  
Author(s):  
B N Cronstein ◽  
S B Kramer ◽  
G Weissmann ◽  
R Hirschhorn

The effects of adenosine were studied on human neutrophils with respect to their generation of superoxide anion, degranulation, and aggregation in response to soluble stimuli. Adenosine markedly inhibited superoxide anion generation by neutrophils stimulated with N-formyl methionyl leucyl phenylalanine (FMLP), concanavalin A (Con A), calcium ionophore A23187, and zymosan-treated serum; it inhibited this response to PMA to a far lesser extent. The effects of adenosine were evident at concentrations ranging from 1 to 1,000 microM with maximal inhibition at 100 microM. Cellular uptake of adenosine was not required for adenosine-induced inhibition since inhibition was maintained despite the addition of dipyridamole, which blocks nucleoside uptake. Nor was metabolism of adenosine required, since both deoxycoformycin (DCF) and erythro-9-(2-hydroxy-3-nonyl) adenine did not interfere with adenosine inhibition of superoxide anion generation. The finding that 2-chloroadenosine, which is not metabolized, resembled adenosine in its ability to inhibit superoxide anion generation added further evidence that adenosine metabolism was not required for inhibition of superoxide anion generation by neutrophils. Unexpectedly, endogenously generated adenosine was present in supernatants of neutrophil suspensions at 0.14-0.28 microM. Removal of endogenous adenosine by incubation of neutrophils with exogenous adenosine deaminase (ADA) led to marked enhancement of superoxide anion generation in response to FMLP. Inactivation of ADA with DCF abrogated the enhancement of superoxide anion generation. Thus, the enhancement was not due to a nonspecific effect of added protein. Nor was the enhancement due to the generation of hypoxanthine or inosine by deamination of adenosine, since addition of these compounds did not affect neutrophil function. Adenosine did not significantly affect either aggregation or lysozyme release and only modestly affected beta-glucuronidase release by neutrophils stimulated with FMLP. These data indicate that adenosine (at concentrations that are present in plasma) acting via cell surface receptors is a specific modulator of superoxide anion generation by neutrophils.

2019 ◽  
Vol 77 (15) ◽  
pp. 3059-3075 ◽  
Author(s):  
Aneta Manda-Handzlik ◽  
Weronika Bystrzycka ◽  
Adrianna Cieloch ◽  
Eliza Glodkowska-Mrowka ◽  
Ewa Jankowska-Steifer ◽  
...  

Abstract Despite great interest, the mechanism of neutrophil extracellular traps (NETs) release is not fully understood and some aspects of this process, e.g. the role of reactive nitrogen species (RNS), still remain unclear. Therefore, our aim was to investigate the mechanisms underlying RNS-induced formation of NETs and contribution of RNS to NETs release triggered by various physiological and synthetic stimuli. The involvement of RNS in NETs formation was studied in primary human neutrophils and differentiated human promyelocytic leukemia cells (HL-60 cells). RNS (peroxynitrite and nitric oxide) efficiently induced NETs release and potentiated NETs-inducing properties of platelet activating factor and lipopolysaccharide. RNS-induced NETs formation was independent of autophagy and histone citrullination, but dependent on the activity of phosphoinositide 3-kinases (PI3K) and myeloperoxidase, as well as selective degradation of histones H2A and H2B by neutrophil elastase. Additionally, NADPH oxidase activity was required to release NETs upon stimulation with NO, as shown in NADPH-deficient neutrophils isolated from patients with chronic granulomatous disease. The role of RNS was further supported by increased RNS synthesis upon stimulation of NETs release with phorbol 12-myristate 13-acetate and calcium ionophore A23187. Scavenging or inhibition of RNS formation diminished NETs release triggered by these stimuli while scavenging of peroxynitrite inhibited NO-induced NETs formation. Our data suggest that RNS may act as mediators and inducers of NETs release. These processes are PI3K-dependent and ROS-dependent. Since inflammatory reactions are often accompanied by nitrosative stress and NETs formation, our studies shed a new light on possible mechanisms engaged in various immune-mediated conditions.


Blood ◽  
1984 ◽  
Vol 64 (6) ◽  
pp. 1184-1192 ◽  
Author(s):  
GW Sullivan ◽  
GR Donowitz ◽  
JA Sullivan ◽  
GL Mandell

Abstract Stimulated neutrophils show ionic fluxes that may function as “transducers” between stimuli and effector functions. Using fluorescent probes, patterns of membrane-associated calcium (chlortetracycline, CTC) and membrane potential (3–3′-dipentyloxacarbocyanine, di-O-C5 (3)) in single living human neutrophils were observed with a fluorescence microscope fitted with an image intensifier and photometer. Fluorescence changes were related to chemiluminescence. In unstimulated neutrophils, CTC and di-O-C5 (3) fluorescence was brightest in the perinuclear region. Di-O-C5 (3) fluorescence was also seen in mitochondria. Neutrophil stimulation with zymosan, phorbol myristate acetate (PMA) or calcium ionophore (A23187) resulted in loss of di-O-C5 (3) and CTC fluorescence and chemiluminescence proportional to the strength of the stimulus. Experiments demonstrated the independence of these processes. (1) Digitonin stimulation caused chemiluminescence and di-O-C5 (3) darkening without loss of CTC fluorescence. (2) Depolarization of neutrophils did not induce CTC darkening or chemiluminescence. (3) Calcium ionophore (A23187) stimulation of neutrophils in calcium-free medium resulted in normal di-O-C5 (3) and CTC darkening, but a blunted chemiluminescence peak. (4) Calcium ionophore (A23187) stimulated the loss of di-O-C5 (3) and CTC fluorescence from chronic granulomatous disease neutrophils, but did not trigger an oxidative burst. Although neutrophil depolarization, calcium release from membranes, and oxidative activity are linked, these processes can clearly be separated.


Blood ◽  
1989 ◽  
Vol 73 (2) ◽  
pp. 588-591 ◽  
Author(s):  
SR McColl ◽  
C Kreis ◽  
JF DiPersio ◽  
P Borgeat ◽  
PH Naccache

Abstract Pre-incubation of human neutrophils with pertussis toxin significantly inhibited the neutrophil-directed biologic actions of granulocyte- macrophage colony-stimulating factor (GM-CSF) in three separate assays: the induction of c-fos mRNA, the enhancement of both platelet- activating factor-induced mobilization of intracellular calcium, and stimulation of leukotriene synthesis by the calcium ionophore A23187. Cholera toxin did not have an effect on the latter two assays. Pre- treatment of human neutrophils with pertussis toxin did not affect the binding of GM-CSF to its surface receptor. These results provide the first evidence that a pertussis toxin substrate plays an important mediatory role in the mechanism of action of GM-CSF.


1989 ◽  
Vol 257 (1) ◽  
pp. H33-H37 ◽  
Author(s):  
Z. S. Katusic ◽  
P. M. Vanhoutte

The calcium ionophore A23187 causes endothelium-dependent contractions in canine basilar arteries. Removal of the endothelium, or treatment with indomethacin or superoxide dismutase (SOD), prevented the endothelium-dependent excitatory effect of the calcium ionophore. Catalase and deferoxamine were without effect. Superoxide anion generated by xanthine plus xanthine oxidase in the presence of catalase caused contractions of the vascular smooth muscle, which were abolished by SOD or heat inactivation of xanthine oxidase. The A23187-induced production of prostaglandins F2 alpha and E2 and thromboxane B2 was abolished by the removal of endothelium and by treatment with indomethacin but was not affected by the presence of SOD plus catalase. These observations are consistent with the hypothesis that superoxide anion, rather than prostaglandins generated by hydroperoxidase activity of cyclooxygenase, is an endothelium-derived contracting factor in canine cerebral arteries.


Blood ◽  
1984 ◽  
Vol 64 (6) ◽  
pp. 1184-1192
Author(s):  
GW Sullivan ◽  
GR Donowitz ◽  
JA Sullivan ◽  
GL Mandell

Stimulated neutrophils show ionic fluxes that may function as “transducers” between stimuli and effector functions. Using fluorescent probes, patterns of membrane-associated calcium (chlortetracycline, CTC) and membrane potential (3–3′-dipentyloxacarbocyanine, di-O-C5 (3)) in single living human neutrophils were observed with a fluorescence microscope fitted with an image intensifier and photometer. Fluorescence changes were related to chemiluminescence. In unstimulated neutrophils, CTC and di-O-C5 (3) fluorescence was brightest in the perinuclear region. Di-O-C5 (3) fluorescence was also seen in mitochondria. Neutrophil stimulation with zymosan, phorbol myristate acetate (PMA) or calcium ionophore (A23187) resulted in loss of di-O-C5 (3) and CTC fluorescence and chemiluminescence proportional to the strength of the stimulus. Experiments demonstrated the independence of these processes. (1) Digitonin stimulation caused chemiluminescence and di-O-C5 (3) darkening without loss of CTC fluorescence. (2) Depolarization of neutrophils did not induce CTC darkening or chemiluminescence. (3) Calcium ionophore (A23187) stimulation of neutrophils in calcium-free medium resulted in normal di-O-C5 (3) and CTC darkening, but a blunted chemiluminescence peak. (4) Calcium ionophore (A23187) stimulated the loss of di-O-C5 (3) and CTC fluorescence from chronic granulomatous disease neutrophils, but did not trigger an oxidative burst. Although neutrophil depolarization, calcium release from membranes, and oxidative activity are linked, these processes can clearly be separated.


Blood ◽  
1990 ◽  
Vol 76 (10) ◽  
pp. 2098-2104 ◽  
Author(s):  
PH Naccache ◽  
C Gilbert ◽  
AC Caon ◽  
M Gaudry ◽  
CK Huang ◽  
...  

Abstract The role of tyrosine kinases in the responses of human neutrophils to chemotactic factors was examined using the recently described inhibitor erbstatin. Pre-incubation with erbstatin decreased the amount of tyrosine phosphorylation induced by the formylated oligopeptide formyl- methionyl-leucyl-phenylalanine (fMet-Leu-Phe) without effecting the binding of [3H]-fMet-Leu-Phe. Erbstatin also dose-dependently inhibited the production of superoxide anion induced by fMet-Leu-Phe and platelet- activating factor, but did not affect the oxidative burst induced by either the calcium ionophore A23187 or the phorbol ester phorbol 12- myristate 13-acetate. Furthermore, erbstatin diminished the cytosolic acidification elicited by fMet-Leu-Phe, platelet-activating factor, and leukotriene B4. In contrast, erbstatin was without effect on the increase in the levels of cytoplasmic free calcium and polymerized actin elicited by fMet-Leu-Phe, C5a, leukotriene B4 and platelet- activating factor, whereas the increase in cytoplasmic free calcium elicited by platelet-derived growth factor was inhibited by erbstatin. In addition, erbstatin affected neither the release of elastase stimulated by these agonists nor the release of beta-glucosaminidase, lysozyme or vitamin B12-binding protein induced by fMet-Leu-Phe. These results indicate that tyrosine protein kinases are involved in the signaling pathways employed by chemotactic factors in the stimulation of selective functional responses (and superoxide production in particular) in human neutrophils.


2019 ◽  
Vol 25 ◽  
pp. 107602961985364
Author(s):  
Valery Leytin ◽  
Armen V. Gyulkhandanyan ◽  
John Freedman

In nucleated cells, the extrinsic pathway of the programmed cell death (apoptosis) is triggered by interaction of death ligands of the tumor necrosis factor superfamily with the death receptors on external cell surface membrane. In this review, we present evidence that, in contrast to nucleated cells, apoptosis in anucleate platelets can be induced through bypassing the death receptors, using instead specific receptors on the platelet surface mediating platelet activation, aggregation, and blood coagulation. These platelet surface receptors include the protease-activated receptor 1 of thrombin and glycoproteins IIbIIIa and Ibα, receptors of fibrinogen, and von Willebrand factor. The pro-apoptotic BH3 mimetic ABT-737 and calcium ionophore A23187 also trigger platelet apoptosis without using death receptors. These agents induce the intrinsic pathway of platelet apoptosis by direct targeting mitochondrial and extra-mitochondrial apoptotic responses.


1985 ◽  
Vol 63 (12) ◽  
pp. 1543-1546 ◽  
Author(s):  
Colette F. Strnad ◽  
Kenneth Wong

The calcium ionophore, A23187, and the tumor-promoting phorbol ester, phorbol 12-myristate 13-acetate (PMA), interacted synergistically to elicit an accelerated superoxide production response in human neutrophils. The lag period preceding PMA-induced superoxide generation was decreased in a dose-dependent manner by A23187 at a concentration range from 1.0 × 10−8 to 1.0 × 10−5 M. Superoxide production rate, however, was subject to biphasic effects. While the rate was potentiated in a dose-dependent manner at A23187 concentrations below 1.0 × 10−6 M, inhibitory influences became manifest at higher concentrations. Total superoxide production was subject to inhibitory effects, characterized by a mean inhibitory dose of 1.3 × 10−6 M. The synergistic interaction of A23187 with PMA is consistent with a role for protein kinase C in neutrophil activation. Inhibition at high A23187 concentrations appeared to result from the effects of elevated intracellular Ca2+ levels on either NADPH oxidase itself, or some step in the transduction process linking protein kinase C to the oxidase complex.


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