Cyclooxygenase-2-dependent generation of 8-epiprostaglandin F2alpha by lipopolysaccharide-activated J774 macrophages.
OBJECTIVE
The generation of 8-epiprostaglandin F2alpha (8-epi-PGF2alpha) by arachidonic acid (AA)- and lipopolysaccharide (LPS)- stimulated J774 macrophages has been investigated.


METHODS
Murine monocyte/macrophage J774 cell line.


METHODS
Cells were incubated with AA or LPS and the amount of 8-epi-PGF2alpha, 6-ketoprostaglandin F1alpha (6-keto-PGF1alpha) and prostaglandin E2 (PGE2) released in the incubation media measured by radioimmunoassay (RIA) or, in some experiments, by enzyme immunoassay (EIA). The effect of dexamethasone (DXM), cycloheximide (CXM) and 5,5 dimethyl-3-(3-fluorophenyl)-4-(4-methylsulfonyl)phenyl-2(5H)-furanone (DFU), a cyclooxygenase-2 (COX-2) selective inhibitor, on LPS-induced generation of AA metabolites was assessed.


RESULTS
AA induced a significant production of 6-ketoPGF1alpha and PGE2, whereas LPS caused a concentration- and time-dependent increase of 8-epi-PGF2alpha, 6-keto-PGF1alpha and PGE2. DXM (2 microM) as well as CXM (1 microM) significantly decreased (p<0.001; n = 4) the LPS-stimulated production of 8-epi-PGF2alpha (by 86% and 82%, respectively), 6-ketoPGF1alpha (by 78% and 74%, respectively) and PGE2 (by 83% and 78%, respectively). Immunostimulated production of AA metabolites was also inhibited by DFU (IC50 0.3+/-0.04 microM; 0.16 +/- 0.02 microM and 0.11 +/- 0.05 microM for 8-epi-PGF2alpha, 6-keto-PGF1alpha and PGE2, respectively.


CONCLUSIONS
These results demonstrate the role of COX-2 in the generation of 8-epi-PGF2alpha by LPS-stimulated J774 macrophages. The relevance of these findings requires further elucidation.
Sautebin
L
L
Department of Experimental Pharmacology, University of Naples Federico II, Italy. sautebin@unina.it
Ianaro
A
A
Rombolà
L
L
Ialenti
A
A
Sala
A
A
Di Rosa
M
M
D015121:6-Ketoprostaglandin F1 alpha / Q000096:biosynthesis; D000818:Animals; D016718:Arachidonic Acid / Q000494:pharmacology; D002460:Cell Line; D003513:Cycloheximide / Q000494:pharmacology; D051546:Cyclooxygenase 2; D003907:Dexamethasone / Q000494:pharmacology; D015237:Dinoprost / Q000031:analogs & derivatives* / Q000378:metabolism; D015232:Dinoprostone / Q000096:biosynthesis; D005938:Glucocorticoids / Q000494:pharmacology; D007527:Isoenzymes / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008262:Macrophage Activation; D008264:Macrophages / Q000378:metabolism*; D051379:Mice; D011451:Prostaglandin-Endoperoxide Synthases / Q000378:metabolism*; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology
D005938:Glucocorticoids; D007527:Isoenzymes; D008070:Lipopolysaccharides; D011500:Protein Synthesis Inhibitors; C075750:8-epi-prostaglandin F2alpha; D016718:Arachidonic Acid; D015121:6-Ketoprostaglandin F1 alpha; D003907:Dexamethasone; D003513:Cycloheximide; D015237:Dinoprost; D051546:Cyclooxygenase 2; D011451:Prostaglandin-Endoperoxide Synthases; D015232:Dinoprostone