Induction of cyclooxygenase by interleukin 1: comparative study between human synovial cells and chondrocytes.
OBJECTIVE
To investigate the regulation of the prostaglandin (PG) synthesis by interleukin 1 (IL-1) in human synovial cells and chondrocytes.


METHODS
Both cell types stimulated by human recombinant IL-1 synthesized PGE2, PGF2 alpha and 6-keto-PGF1 alpha.


RESULTS
PGE2 was the major PG synthesized. When arachidonic acid was added exogenously at the end of the stimulation, an increase in the prostaglandin synthesis was observed after 6 and 24 h suggesting that cyclooxygenase is the limiting enzyme. Using actinomycin D and cycloheximide, PG synthesis was shown to be protein synthesis dependent. Inhibition of the constitutive cyclooxygenase by aspirin before the IL-1 stimulation confirmed that the increased prostaglandin synthesis was due to a de novo synthesis of cyclooxygenase.


CONCLUSIONS
This enzyme induction by IL-1 was found to be similar in both cell types.
Knott
I
I
Laboratoire de Biochimie Cellulaire, Facultés Universitaires Notre-Dame de la Paix, Namur, Belgium.
Dieu
M
M
Burton
M
M
Houbion
A
A
Remacle
J
J
Raes
M
M
D016718:Arachidonic Acid / Q000494:pharmacology; D001241:Aspirin / Q000494:pharmacology; D002356:Cartilage / Q000187:drug effects* / Q000201:enzymology; D002478:Cells, Cultured; D003520:Cyclophosphamide / Q000494:pharmacology; D003609:Dactinomycin / Q000494:pharmacology; D015232:Dinoprostone / Q000096:biosynthesis; D004790:Enzyme Induction / Q000187:drug effects; D006801:Humans; D007375:Interleukin-1 / Q000494:pharmacology*; D010741:Phospholipases A / Q000378:metabolism; D011451:Prostaglandin-Endoperoxide Synthases / Q000096:biosynthesis* / Q000235:genetics; D011453:Prostaglandins / Q000096:biosynthesis*; D014176:Protein Biosynthesis / Q000187:drug effects; D011994:Recombinant Proteins / Q000494:pharmacology; D013583:Synovial Membrane / Q000187:drug effects* / Q000201:enzymology; D014158:Transcription, Genetic / Q000187:drug effects
D007375:Interleukin-1; D011453:Prostaglandins; D011994:Recombinant Proteins; D003609:Dactinomycin; D016718:Arachidonic Acid; D003520:Cyclophosphamide; D011451:Prostaglandin-Endoperoxide Synthases; D010741:Phospholipases A; D015232:Dinoprostone; D001241:Aspirin