Effects of non-steroidal antiinflammatory drugs and dexamethasone on the activity and expression of matrix metalloproteinase-1, matrix metalloproteinase-3 and tissue inhibitor of metalloproteinases-1 by bovine articular chondrocytes.
OBJECTIVE
To determine the in-vitro effects of several non-steroidal antiinflammatory drugs and the glucocorticoid dexamethasone on the IL-1 altered expression and activity of MMP-1, MMP-3 and TIMP-1 by bovine articular chondrocytes.


METHODS
Bovine chondrocytes were cultured in alginate gel beads. Cells were treated with IL-1alpha in the presence of vehicle or drugs at various concentrations. After 48 h mRNA expression of MMP-1, MMP-3, and of the tissue inhibitor of metalloproteinases (TIMP-1) was analysed by RT-PCR-ELISA. The protein synthesis of TIMP-1 and MMP-3 was determined by immunoprecipitation. The activity of enzymes and inhibitors was measured by functional assays.


RESULTS
IL-1 increased the expression and activity of MMPs. In contrast, TIMP activity remained unchanged although TIMP-1 expression was down-regulated. All tested NSAIDs and dexamethasone inhibited collagenase activity induced by IL-1. Transcript levels of MMP-1, however, were only reduced by indomethacin, meloxicam, naproxen and dexamethasone. Proteoglycanase activity was only reduced by indomethacin, meloxicam and dexamethasone. These effects were pre-translational as confirmed by immunoprecipitation. The IL-1 decreased expression of TIMP-1 was further reduced by dexamethasone, which resulted in a significant loss of TIMP activity. No effects on TIMP activity or TIMP-1 biosynthesis were observed after treatment of chondrocytes with NSAIDs.


CONCLUSIONS
Our studies clearly demonstrate that marked differences exist between individual NSAIDs with respect to their ability to modulate the imbalance between proteases and inhibitors during OA and RA, suggesting that the respective modes of action are independent of the inhibition of cyclooxygenases. Due to their co-regulation of MMPs and TIMP(s) glucocorticoids should be carefully studied for their overall effect on ECM proteolysis.
Sadowski
T
T
Institute of Pharmacology and Toxicology, University of Bonn, Germany. thorsten.sadowski@biochem.uni-kiel.de
Steinmeyer
J
J
D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology*; D002358:Cartilage, Articular / Q000201:enzymology; D002417:Cattle; D002478:Cells, Cultured; D019902:Chondrocytes / Q000187:drug effects / Q000201:enzymology*; D017364:Collagenases / Q000378:metabolism; D003907:Dexamethasone / Q000494:pharmacology*; D005938:Glucocorticoids / Q000494:pharmacology*; D007213:Indomethacin / Q000494:pharmacology; D007375:Interleukin-1 / Q000494:pharmacology; D008297:Male; D020781:Matrix Metalloproteinase 1 / Q000235:genetics / Q000378:metabolism; D019278:Matrix Metalloproteinase 3 / Q000235:genetics / Q000378:metabolism; D020782:Matrix Metalloproteinases / Q000235:genetics / Q000378:metabolism*; D000077239:Meloxicam; D008666:Metalloendopeptidases / Q000378:metabolism; D009288:Naproxen / Q000494:pharmacology; D011233:Precipitin Tests / Q000379:methods; D012333:RNA, Messenger / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013843:Thiazines / Q000494:pharmacology; D013844:Thiazoles / Q000494:pharmacology; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000235:genetics / Q000378:metabolism*
D000894:Anti-Inflammatory Agents, Non-Steroidal; D005938:Glucocorticoids; D007375:Interleukin-1; D012333:RNA, Messenger; D013843:Thiazines; D013844:Thiazoles; D019715:Tissue Inhibitor of Metalloproteinase-1; D009288:Naproxen; D003907:Dexamethasone; C022474:proteoglycan-degrading metalloendopeptidases; D017364:Collagenases; D020782:Matrix Metalloproteinases; D008666:Metalloendopeptidases; D019278:Matrix Metalloproteinase 3; D020781:Matrix Metalloproteinase 1; D000077239:Meloxicam; D007213:Indomethacin