Incorporation of arachidonic acid and eicosapentaenoic acid into phospholipids by polymorphonuclear leukocytes in vitro

Lipids ◽  
1984 ◽  
Vol 19 (8) ◽  
pp. 573-577 ◽  
Author(s):  
Jen-Sie Tou
Keyword(s):  
Arachidonic Acid ◽  
Eicosapentaenoic Acid ◽  
Polymorphonuclear Leukocytes

scholarly journals Arachidonic acid metabolism and the adhesion of human polymorphonuclear leukocytes to cultured vascular endothelial cells

Blood ◽  
1983 ◽  
Vol 62 (4) ◽  
pp. 889-895 ◽  
Author(s):  
MR Buchanan ◽  
MJ Vazquez ◽  
MA Jr Gimbrone
Keyword(s):  
Endothelial Cells ◽  
Arachidonic Acid ◽  
Endothelial Cell ◽  
Polymorphonuclear Leukocytes ◽  
Acid Metabolism ◽  
Arachidonic Acid Metabolism ◽  
Vascular Endothelial ◽  
Endothelial Monolayers

Abstract Polymorphonuclear leukocytes (PMN) adhere to the vascular endothelial lining in vivo and to the surfaces of cultured endothelial cells in vitro, but the mechanisms of these cellular interactions remain unclear. Arachidonic acid metabolites, both cyclooxygenase- and lipoxygenase-derived, have been shown to influence PMN locomotion, secretion, and adhesion to artificial surfaces. To determine whether such mediators also are involved in regulating PMN-endothelial cell interactions, we have examined the effects of prostacyclin and various inhibitors of arachidonic acid metabolism on the adherence of radiolabeled PMN to cultured bovine aortic endothelial cells. Confluent endothelial monolayers were incubated with washed suspensions of radiolabeled human PMN (which contained less than 1% platelet contamination) at 37 degrees C for 30 min, then subjected to a standardized wash procedure and the number of adherent leukocytes determined radiometrically. Under basal conditions, i.e., in the absence of exogenous activating stimuli, 4,163 +/- 545 PMN adhered per square millimeter of endothelial surface (mean +/- SEM, n = 12). This basal adhesion (which corresponds to approximately 4–5 leukocytes per endothelial cell) was unaffected when the leukocytes and endothelial monolayers were pretreated with cyclooxygenase inhibitors (100 microM aspirin or 1–5 microM indomethacin) or PGI2 (10(-9)-10(6) M). Thus, basal PMN-endothelial adhesion in this in vitro model system does not appear to be dependent on endogenous cyclooxygenase derivatives of arachidonate or to be sensitive to inhibition by exogenous prostacyclin. In contrast, leukocyte adhesion was significantly reduced by pretreatment with 5,8,11,14- or 4,7,10,13-eicosatetraynoic acid, 0.5- 5 mM sodium salicylate, or 10–1,000 microM indomethacin, antiinflammatory agents that can interfere with the metabolism of arachidonic acid via non-cyclooxygenase-dependent mechanisms. These observations may be relevant to the interactions of circulating PMN with vascular endothelium under both physiologic and pathophysiologic conditions in vivo.

scholarly journals Arachidonic acid metabolism and the adhesion of human polymorphonuclear leukocytes to cultured vascular endothelial cells

Blood ◽  
1983 ◽  
Vol 62 (4) ◽  
pp. 889-895
Author(s):  
MR Buchanan ◽  
MJ Vazquez ◽  
MA Jr Gimbrone
Keyword(s):  
Endothelial Cells ◽  
Arachidonic Acid ◽  
Endothelial Cell ◽  
Polymorphonuclear Leukocytes ◽  
Acid Metabolism ◽  
Arachidonic Acid Metabolism ◽  
Vascular Endothelial ◽  
Endothelial Monolayers

Polymorphonuclear leukocytes (PMN) adhere to the vascular endothelial lining in vivo and to the surfaces of cultured endothelial cells in vitro, but the mechanisms of these cellular interactions remain unclear. Arachidonic acid metabolites, both cyclooxygenase- and lipoxygenase-derived, have been shown to influence PMN locomotion, secretion, and adhesion to artificial surfaces. To determine whether such mediators also are involved in regulating PMN-endothelial cell interactions, we have examined the effects of prostacyclin and various inhibitors of arachidonic acid metabolism on the adherence of radiolabeled PMN to cultured bovine aortic endothelial cells. Confluent endothelial monolayers were incubated with washed suspensions of radiolabeled human PMN (which contained less than 1% platelet contamination) at 37 degrees C for 30 min, then subjected to a standardized wash procedure and the number of adherent leukocytes determined radiometrically. Under basal conditions, i.e., in the absence of exogenous activating stimuli, 4,163 +/- 545 PMN adhered per square millimeter of endothelial surface (mean +/- SEM, n = 12). This basal adhesion (which corresponds to approximately 4–5 leukocytes per endothelial cell) was unaffected when the leukocytes and endothelial monolayers were pretreated with cyclooxygenase inhibitors (100 microM aspirin or 1–5 microM indomethacin) or PGI2 (10(-9)-10(6) M). Thus, basal PMN-endothelial adhesion in this in vitro model system does not appear to be dependent on endogenous cyclooxygenase derivatives of arachidonate or to be sensitive to inhibition by exogenous prostacyclin. In contrast, leukocyte adhesion was significantly reduced by pretreatment with 5,8,11,14- or 4,7,10,13-eicosatetraynoic acid, 0.5- 5 mM sodium salicylate, or 10–1,000 microM indomethacin, antiinflammatory agents that can interfere with the metabolism of arachidonic acid via non-cyclooxygenase-dependent mechanisms. These observations may be relevant to the interactions of circulating PMN with vascular endothelium under both physiologic and pathophysiologic conditions in vivo.

Phorbol ester up-regulates capacities for nuclear translocation and phosphorylation of 5-lipoxygenase in Mono Mac 6 cells and human polymorphonuclear leukocytes

Blood ◽  
2001 ◽  
Vol 97 (8) ◽  
pp. 2487-2495 ◽  
Author(s):  
Oliver Werz ◽  
Jenny Klemm ◽  
Bengt Samuelsson ◽  
Olof Rådmark
Keyword(s):  
Arachidonic Acid ◽  
Polymorphonuclear Leukocytes ◽  
Phorbol Esters ◽  
Nuclear Translocation ◽  
Kinase Inhibitor ◽  
Calcium Ionophore ◽  
Monocytic Cell ◽  
Monocytic Cell Line ◽  
Human Polymorphonuclear Leukocytes

Abstract The leukotrienes are inflammatory mediators derived from arachidonic acid. It was demonstrated that the priming of leukocytes with phorbol-12-myristate-13-acetate (PMA) leads to the increased formation of 5-lipoxygenase (5-LO) products in parallel with the increased association of 5-LO with the nucleus and the activation of kinases that can phosphorylate 5-LO in vitro. Stimulation of the monocytic cell line Mono Mac 6 with calcium ionophore gave low 5-LO product formation and no detectable redistribution of 5-LO. However, after priming of Mono Mac 6 cells with phorbol esters, ionophore led to the association of 45% to 75% of cellular 5-LO with the nuclear membrane, to 5-LO kinase activation, to enhanced release of arachidonate, and to substantial leukotriene synthesis. Similar results were obtained for human polymorphonuclear leukocytes stimulated with low-dose ionophore. In addition, for each cell type, PMA priming up-regulated leukotriene biosynthesis in the presence of exogenous arachidonic acid. A protein kinase inhibitor, calphostin C, reduced the association of 5-LO with the nucleus and 5-LO kinase activity, and the formation of 5-LO products was inhibited. These results suggest that PMA up-regulates leukotriene biosynthesis not only by increasing the release of endogenous arachidonate, but also by increasing the capacity for 5-LO phosphorylation and for the translocation of 5-LO to the nucleus in leukocytes.

Chlorobutanol, a Preservative of Desmopressin, Inhibits Human Platelet Aggregation and Release In Vitro

1990 ◽  
Vol 64 (03) ◽  
pp. 473-477 ◽  
Author(s):  
Shih-Luen Chen ◽  
Wu-Chang Yang ◽  
Tung-Po Huang ◽  
Shiang Wann ◽  
Che-ming Teng
Keyword(s):  
Arachidonic Acid ◽  
Platelet Aggregation ◽  
Atp Release ◽  
Free Calcium ◽  
Dependent Manner ◽  
Antiplatelet Effect ◽  
Human Platelet Aggregation ◽  
Acid Pathway ◽  
Arachidonic Acid Pathway

SummaryTherapeutic preparations of desmopressin for parenteral use contain the preservative chlorobutanol (5 mg/ml). We show here that chlorobutanol is a potent inhibitor of platelet aggregation and release. It exhibited a significant inhibitory activity toward several aggregation inducers in a concentration- and time-dependent manner. Thromboxane B2 formation, ATP release, and elevation of cytosolic free calcium caused by collagen, ADP, epinephrine, arachidonic acid and thrombin respectively were markedly inhibited by chlorobutanol. Chlorobutanol had no effect on elastase- treated platelets and its antiplatelet effect could be reversed. It is concluded that the antiplatelet effect of chlorobutanol is mainly due to its inhibition on the arachidonic acid pathway but it is unlikely to have a nonspecitic toxic effect. This antiplatelet effect of chlorobutanol suggests that desmopressin, when administered for improving hemostasis, should not contain chlorobutanol as a preservative.

Defibrotide Inhibits Platelet Activation by Cathepsin G Released From Stimulated Polymorphonuclear Leukocytes

1992 ◽  
Vol 67 (06) ◽  
pp. 660-664 ◽  
Author(s):  
Virgilio Evangelista ◽  
Paola Piccardoni ◽  
Giovanni de Gaetano ◽  
Chiara Cerletti
Keyword(s):  
Platelet Activation ◽  
Polymorphonuclear Leukocytes ◽  
Direct Interaction ◽  
Cathepsin G ◽  
In Vivo Test ◽  
Cell Functions ◽  
Test Models ◽  
Antithrombotic Effects

SummaryDefibrotide is a polydeoxyribonucleotide with antithrombotic effects in experimental animal models. Most of the actions of this drug have been observed in in vivo test models but no effects have been reported in in vitro systems. In this paper we demonstrate that defibrotide interferes with polymorphonuclear leukocyte-induced human platelet activation in vitro. This effect was not related to any direct interaction with polymorphonuclear leukocytes or platelets, but was due to the inhibition of cathepsin G, the main biochemical mediator of this cell-cell cooperation. Since cathepsin G not only induces platelet activation but also affects some endothelial cell functions, the anticathepsin G activity of defibrotide could help to explain the antithrombotic effect of this drug.

The d-Enantiomer Form of Indobufen Totally Accounts for the Anti-Cyclooxygenase and Antiplatelet Activity Ex Vivo and for the Increase in Bleeding Time by Indobufen in Man

1992 ◽  
Vol 67 (02) ◽  
pp. 258-263 ◽  
Author(s):  
Raffaele De Caterina ◽  
Rosa Sicari ◽  
An Yan ◽  
Walter Bernini ◽  
Daniela Giannessi ◽  
...  
Keyword(s):  
Arachidonic Acid ◽  
Platelet Aggregation ◽  
Plasma Levels ◽  
Bleeding Time ◽  
Ex Vivo ◽  
Random Sequence ◽  
Antiplatelet Agent ◽  
Antiplatelet Drug ◽  
Double Blind

SummaryIndobufen is an antiplatelet drug able to inhibit thromboxane production and cyclooxygenase-dependent platelet aggregation by a reversible inhibition of cyclooxygenase. Indobufen exists in two enantiomeric forms, of which only d-indobufen is active in vitro in inhibiting cyclooxygenase. In order to verify that also inhibition of platelet function is totally accounted for by d-indobufen, ten patients with proven coronary artery disease (8 male, 2 female, age, mean ± S.D., 58.7 ± 7.5 years) were given, in random sequence, both 100 mg d-indobufen and 200 mg dl-indobufen as single administrations in a double-blind crossover design study with a washout period between treatments of 72 h. In all patients thromboxane (TX) B2 generation after spontaneous clotting (at 0, 1, 2, 4, 6, 8, 12, 24 h), drug plasma levels (at the same times), platelet aggregation in response to ADP, adrenaline, arachidonic acid, collagen, PAF, and bleeding time (at 0, 2, 12 h) were evaluated after each treatment. Both treatments determined peak inhibition of TXB2 production at 2 h from administration, with no statistical difference between the two treatments (97 ±3% for both treatments). At 12 h inhibition was 87 ± 6% for d-indobufen and 88 ± 6% for dl-indobufen (p = NS). Inhibition of TXB2 production correlated significantly with plasma levels of the drugs. Maximum inhibitory effect on aggregation was seen in response to collagen 1.5 pg/ml (63 ± 44% for d-indobufen and 81 ± 22% for dl-indobufen) and arachidonic acid 0.5-2 mM (78 ± 34% for d-indobufen and 88 ± 24% for dl-indobufen) at 2 h after each administration. An effect of both treatments on platelet aggregation after 12 h was present only for adrenaline 2 μM (55 ± 41% for d-indobufen and 37 ± 54% for dl-indobufen), collagen 1.5 pg/ml (69 ± 30% for d-indobufen and 51 ± 61% for dl-indobufen), arachidonic acid 0.5-2 mM (56 ± 48% for d-indobufen and 35 ± 49% for dl-indobufen). The extent of inhibition of TX production and the extent of residual platelet aggregation were never significantly different between treatments. Bleeding time prolongation was similar in the two treatment groups without showing a pronounced and long lasting effect (from 7.0 ± 2.0 min to 10.0 ± 3.0 min at 2 h and 8.0 ± 2.0 min at 12 h for d-indobufen; from 6.0 ±1.0 min to 8.5 ± 2.0 min at 2 h and 8.0 ± 1.0 min at 12 h for dl-indobufen). These results demonstrate that the biological activity of dl-indobufen as an antiplatelet agent in vivo is totally accounted for by d-indobufen.

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