Evaluation of the influence of prostaglandin E2 on recombinant equine interleukin-1beta-stimulated matrix metalloproteinases 1, 3, and 13 and tissue inhibitor of matrix metalloproteinase 1 expression in equine chondrocyte cultures.
OBJECTIVE
To determine the effects of prostaglandin E2 (PGE2) on recombinant equine interleukin (IL)-1beta-stimulated expression of matrix metalloproteinases (MMP 1, MMP 3, MMP 13) and tissue inhibitor of matrix metalloproteinase 1 (TIMP 1) in vitro.


METHODS
Cultured equine chondrocytes.


METHODS
Stationary monolayers of first-passage chondrocytes were exposed to graduated concentrations of PGE2 with or without a subsaturating dose (50 pg/ml) of recombinant equine IL-1beta (reIL-1beta) to induce expression of MMP 1, MMP 3, MMP 13, and TIMP 1, followed by RNA isolation and northern blotting. In subsequent experiments, gene expression was similarly quantified from mRNA isolated from cultures pretreated with phenylbutazone to quench endogenous PGE2 synthesis, followed by exposure to reIL-1beta and exogenous PGE2 (5 mg/ml) with appropriate controls.


RESULTS
Exogenous PGE2 (10 mg/ml) significantly reduced reIL-1beta-induced expression of MMP 1, MMP 3, MMP 13, and TIMP 1. Abrogation of cytokine induction with this dose of PGE2 was comparable to that for dexamethasone (10(-5) M) control. Similarly, pretreatment with phenylbutazone, followed by exposure to relL-1beta and PGE2 (5 mg/ml), was associated with a reduced expression of the genes of interest, an effect that was significant for MMP 1, MMP 13, and TIMP 1.


CONCLUSIONS
The MMP and TIMP 1 are important mediators in the pathophysiologic events in osteoarthritis. The potential for physiologically relevant regulation of expression of these genes by PGE2 is a consideration in the use of drugs that inhibit prostanoid synthesis in the treatment of equine arthropathies.
Tung
Jayne T
JT
Department of Large Animal Clinical Sciences, Michigan State University, East Lansing 48824, USA.
Arnold
Carolyn E
CE
Alexander
Lee H
LH
Yuzbasiyan-Gurkan
Vilma
V
Venta
Patrick J
PJ
Richardson
Dean W
DW
Caron
John P
JP
D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology; D015152:Blotting, Northern / Q000662:veterinary; D019902:Chondrocytes / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology*; D015232:Dinoprostone / Q000494:pharmacology*; D004347:Drug Interactions; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D006736:Horses / Q000378:metabolism*; D007375:Interleukin-1 / Q000494:pharmacology*; D020782:Matrix Metalloproteinases / Q000096:biosynthesis* / Q000235:genetics; D010653:Phenylbutazone / Q000494:pharmacology; D012313:RNA / Q000737:chemistry / Q000235:genetics; D011994:Recombinant Proteins / Q000494:pharmacology; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000662:veterinary; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000096:biosynthesis* / Q000235:genetics
D000894:Anti-Inflammatory Agents, Non-Steroidal; D007375:Interleukin-1; D011994:Recombinant Proteins; D019715:Tissue Inhibitor of Metalloproteinase-1; D012313:RNA; D020782:Matrix Metalloproteinases; D010653:Phenylbutazone; D015232:Dinoprostone