Comparison of 1-oleoyl-2-acetyl-glycerol and phorbol myristate acetate as secretagogues for human neutrophils

1986 ◽  
Vol 64 (8) ◽  
pp. 1149-1152 ◽  
Author(s):  
Kenneth Wong ◽  
Christine Chew
Keyword(s):  
Phorbol Myristate Acetate ◽  
Cellular Responses ◽  
Current Evidence ◽  
Human Neutrophils ◽  
Myristate Acetate ◽  
First Order ◽  
Regulatory Constraints ◽  
Kinase C ◽  
Rate Of Decay ◽  
The Stability

Cellular responses induced in human neutrophils by the synthetic diacylglycerol, 1-oleoyl-2-acetyl-glycerol (OAG), paralleled those induced by phorbol myristate acetate (PMA). Like PMA, OAG caused the preferential release of enzymes from specific granules and promoted superoxide (O2−) generation. The efficacy of OAG was similar to that for PMA, but its potency was lower by four orders of magnitude. First derivative kinetic analysis showed that rates of O2− generation elicited by PMA decayed exponentially in a first order manner; the half life was found to be 21 ± 6 min. Results obtained in studies carried out with high OAG concentrations were similar except that after 40 min, the rate of decay increased and became complex order. This difference was attributed to the greater susceptibility of OAG to metabolic alteration, and was reflected in the NADPH oxidase activity of granule rich membrane fractions (GRF) of cells stimulated for 90 min with PMA or OAG. It was found that the O2− generating activity of the PMA treated GRF was significantly greater than that for the OAG treated fraction. Current evidence indicates that cellular responses arise from direct activation of protein kinase C by PMA-OAG. The stability of this complex and the bypassing of normal regulatory constraints may account for the relative longevity of the PMA–OAG O2− respiratory burst.

Effect of phorbol myristate acetate and the chemotactic peptide fNLPNTL on shape and movement of human neutrophils

1987 ◽  
Vol 88 (3) ◽  
pp. 399-406 ◽  
Author(s):  
F.J. Roos ◽  
A. Zimmermann ◽  
H.U. Keller
Keyword(s):  
Phorbol Myristate Acetate ◽  
Human Neutrophils ◽  
Chemotactic Peptide ◽  
Myristate Acetate ◽  
Locomotor Apparatus ◽  
Kinase C ◽  
Motile Cells ◽  
Chemotactic Peptides ◽  
Intracellular Organelles ◽  
Stimulation Of

The results show that the distinct types of shape produced by phorbol myristate acetate (PMA) and by chemotactic peptides (fNLPNTL) are associated with distinct types of neutrophil movement. Whereas the chemotactic peptide can induce front-tail polarity characterized by an expanding front, a contracted tail and preferential unidirectional movements of intracellular organelles, PMA can only elicit non-polar movements characterized by random formation and retraction of projections all over the surface, intracellular movements of organelles being ill-defined and changing in direction. Combined stimulation of human neutrophils with PMA and fNLPNTL results in a suppression of peptide-induced polarity and the formation of non-polar motile cells resembling those stimulated with PMA alone. The results suggest that the diacylglycerol-protein kinase C pathway may be instrumental in transducing or modulating signals to the locomotor apparatus of the cell. PMA-treated cells are, however, still capable of developing directional responses when appropriately stimulated. The findings lead to the hypothesis that distinct types of neutrophil movements are preferentially associated with distinct functions.

scholarly journals Regulation of CD18 expression in human neutrophils as related to shape changes

1993 ◽  
Vol 106 (2) ◽  
pp. 493-501
Author(s):  
A. Volz
Keyword(s):  
Phorbol Myristate Acetate ◽  
Surface Expression ◽  
Cytochalasin D ◽  
Human Neutrophils ◽  
Chemotactic Peptide ◽  
Myristate Acetate ◽  
Surface Distribution ◽  
Quantitative Expression ◽  
High Concentrations ◽  
Shape Changes

The study analyses the distribution and quantitative expression of surface CD18 of neutrophils exposed to distinct stimuli that produce different types of continuous shape changes, including types that are associated with locomotion and others that are not. The chemotactic peptide N-formyl-L-norleucyl-L-leucyl-L-phenylalanine, colchicine and nocodazole were used to induce a polarized locomotor morphology, phorbol myristate acetate, 1,2-dioctanoylglycerol and 1-oleoyl-2-acetyl-glycerol to induce non-polar motile cells ruffling all over the surface and 2H2O to induce non-polar cells performing circus movements as have been previously described. Except for colchicine and nocodazole, these stimuli increased surface expression of CD18. Thus, stimulated shape changes are frequently, though not always, associated with increased surface expression of CD18. High concentrations (10(−7) to 10(−5) M) of phorbol myristate acetate but not of chemotactic peptide induced down-regulation of surface CD18. Cytochalasin D (10(−4) M) stimulated CD18 expression even though it inhibited shape changes. The surface distribution of CD18 determined by light microscopy was uniform in unstimulated cells or in various forms of stimulation except for cells treated with 10(−5) M cytochalasin D. Cytochalasin D (10(−5) M) produced CD18 accumulation at the pole opposite the F-actin cap. Experiments with colchicine, nocodazole, 2H2O and cytochalasin D suggest that microtubules as well as microfilaments modulate surface expression of CD18. The results suggest that protein kinase C and phosphatases play a role in regulating surface expression of CD18 in neutrophils.(ABSTRACT TRUNCATED AT 250 WORDS)

Regulation of paracellular permeability in Caco-2 cell monolayers by protein kinase C

1993 ◽  
Vol 265 (5) ◽  
pp. G955-G962 ◽  
Author(s):  
W. F. Stenson ◽  
R. A. Easom ◽  
T. E. Riehl ◽  
J. Turk
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Phorbol Myristate Acetate ◽  
Paracellular Permeability ◽  
Colonic Adenocarcinoma ◽  
Myristate Acetate ◽  
Cell Monolayers ◽  
Kinase C ◽  
Endogenous Substrate ◽  
Stimulation Of

Caco-2 cells are an enterocyte-like cell line derived from a human colonic adenocarcinoma. Paracellular permeability was assessed in monolayers of these cells by transmonolayer resistance and by the permeation of [3H]mannitol across the monolayer. Paracellular permeability was increased by the protein kinase C (PKC) activator phorbol 12-myristate 13-acetate (50 nM), carbachol (500 microM), and the combination of carbachol (50 microM) and monolein (100 microM), an inhibitor of diacylglycerol kinase, as manifested by a decrease in transmonolayer resistance and an increase in mannitol permeation. The effects of all of these stimuli on transmonolayer resistance were inhibited by staurosporine (3 nM), an inhibitor of PKC. The effects of carbachol plus monolein were also inhibited by atropine (0.1 microM), a muscarinic antagonist. Treatment of the monolayers with each of the stimuli was associated with translocation of PKC activity from cytosol to a membrane-associated state. Stimulation of Caco-2 cell monolayers with phorbol myristate acetate or with the combination of carbachol and monolein was also associated with phosphorylation of the MARCKS protein, an endogenous substrate of PKC. These data support the hypothesis that intestinal paracellular permeability is regulated by the activity of enterocyte PKC and demonstrate that the increase in paracellular permeability induced by binding of carbachol to the muscarinic receptor is mediated by activation of PKC.

Involvement of protein kinase C in macrophage activation by poly(I.C)

1994 ◽  
Vol 266 (1) ◽  
pp. C134-C142 ◽  
Author(s):  
F. R. Lake ◽  
E. C. Dempsey ◽  
J. D. Spahn ◽  
D. W. Riches
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Phorbol Myristate Acetate ◽  
Mrna Levels ◽  
Myristate Acetate ◽  
Western Blots ◽  
Level Of Involvement ◽  
Polycytidylic Acid ◽  
Kinase C ◽  
Polyinosinic Polycytidylic Acid

The expression of cytocidal activity is initiated by the interaction of macrophages with priming [e.g., interferon (IFN)] and triggering stimuli (polyinosinic-polycytidylic acid). We have shown that the triggering step can be initiated in a Ca(2+)-dependent fashion and hypothesized that protein kinase C (PKC) may couple the Ca2+ signal to the expression of a gene product, Bf, that accompanies the expression of macrophage cytocidal activity. Exposure of IFN-primed macrophages to polyinosinic-polycytidylic acid in the presence of the PKC inhibitors H-7 or sphingosine or after downregulation of PKC with phorbol myristate acetate markedly inhibited Bf synthesis. Western blots of macrophage lysates revealed the presence of the alpha-, delta-, and zeta-isozymes of PKC, and all were found to be downregulated by phorbol myristate acetate. Inhibition of PKC also prevented the increase in IFN-beta mRNA levels and partially blocked the response to IFN-beta. These data suggest that the alpha-, delta-, and zeta-isozymes of PKC are involved in signaling leading to Bf expression and that the level of involvement is restricted to the induction and response to IFN-beta.

scholarly journals The chlorinating potential of the human monocyte

Blood ◽  
1983 ◽  
Vol 62 (3) ◽  
pp. 645-651 ◽  
Author(s):  
MB Lampert ◽  
SJ Weiss
Keyword(s):  
Phorbol Myristate Acetate ◽  
Cell Concentration ◽  
Human Monocyte ◽  
Human Neutrophils ◽  
Human Monocytes ◽  
Taurine Chloramine ◽  
Myristate Acetate ◽  
Opsonized Zymosan ◽  
Nitrobenzoic Acid ◽  
Characteristic Absorption Peak

Abstract Human monocytes incubated with phorbol myristate acetate (PMA) or opsonized zymosan particles can chlorinate the beta-amino acid taurine to its monochloramine derivative. Taurine monochloramine can then be quantitated by its ability to oxidize 5-thio-2-nitrobenzoic acid to its disulfide or by its characteristic absorption peak at 252 nm. Stimulated, but not resting, monocytes chlorinated taurine by a process dependent on time, cell concentration, and pH. The formation of taurine chloramine by stimulated monocytes could be inhibited by catalase, azide, or cyanide, was unaffected by superoxide dismutase, and was stimulated by exogenous myeloperoxidase. Thus, taurine chloramine generation by human monocytes appeared dependent on both H2O2 and myeloperoxidase. Compared to human neutrophils, the monocyte could generate similar amounts of chloramine when stimulated with phorbol myristate acetate, but far less if opsonized zymosan particles were used as the trigger. Based on the known ability of the H2O2- myeloperoxidase-Cl- system to generate free HOCl, it would seem that this oxidant is the most likely species responsible for the monocyte- mediated chlorination reactions. Thus, we have used a simple quantitative assay to demonstrate the ability of the human monocyte to generate large quantities of a highly reactive and toxic oxygen metabolite.

Tetanus toxin attenuates the ability of phorbol myristate acetate to mobilize cytosolic protein kinase C in NG-108 cells

Toxicon ◽  
1990 ◽  
Vol 28 (1) ◽  
pp. 13-19 ◽  
Author(s):  
Robert V. Considine ◽  
John K. Bielicki ◽  
Lance L. Simpson ◽  
Joseph R. Sherwin
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Phorbol Myristate Acetate ◽  
Tetanus Toxin ◽  
Myristate Acetate ◽  
Cytosolic Protein ◽  
Kinase C
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