Differential effects of p38MAP kinase inhibitors on the expression of inflammation-associated genes in primary, interleukin-1beta-stimulated human chondrocytes.
OBJECTIVE
A main challenge in the therapy of osteoarthritis (OA) is the development of drugs that will modify the disease. Reliable test systems are necessary to enable an efficient screening of therapeutic substances. We therefore established a chondrocyte-based in vitro cell culture model in order to characterize different p38MAPK inhibitors.


METHODS
Interleukin-1beta (IL-1beta)-stimulated human OA chondrocytes were treated with the p38MAPK inhibitors Birb 796, pamapimod, SB203580 and the new substance CBS-3868. Birb 796- and SB203580-treated cells were analysed in a genome-wide microarray analysis. The efficacy of all inhibitors was characterized by quantitative gene expression analysis and the quantification of PGE(2) and NO release.


RESULTS
Microarray analysis revealed inhibitor-specific differences in gene expression. Whereas SB203580 had a broad effect on chondrocytes, Birb 796 counteracted the IL-1beta effect more specifically. All p38MAPK inhibitors significantly inhibited the IL-1beta-induced gene expression of COX-2, mPGES1, iNOS, matrix metalloproteinase 13 (MMP13) and TNFRSF11B, as well as PGE(2) release. Birb 796 and CBS-3868 showed a higher efficacy than SB203580 and pamapimod at inhibiting the expression of COX-2 and MMP13 genes, as well as PGE(2) release. In the case of mPGES1 and TNFRSF11B gene expression, CBS-3868 exceeded the efficacy of Birb 796.


CONCLUSIONS
Our test system could differentially characterize inhibitors of the same primary pharmaceutical target. It reflects processes relevant in OA and is based on chondrocytes that are mainly responsible for cartilage degradation. It therefore represents a valuable tool for drug screening in between functional in vitro testing and in vivo models.
Joos
H
H
Division for Biochemistry of Joint and Connective Tissue Diseases, Department of Orthopedics, University of Ulm, Ulm, Germany.
Albrecht
W
W
Laufer
S
S
Brenner
R E
RE
D018929:Cell Culture Techniques; D019902:Chondrocytes / Q000187:drug effects* / Q000378:metabolism*; D015232:Dinoprostone / Q000378:metabolism; D004353:Drug Evaluation, Preclinical / Q000379:methods*; D015870:Gene Expression / Q000187:drug effects*; D006801:Humans; D018836:Inflammation Mediators / Q000378:metabolism*; D053583:Interleukin-1beta / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D009569:Nitric Oxide / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods; D047428:Protein Kinase Inhibitors / Q000494:pharmacology*; D048051:p38 Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors*
D018836:Inflammation Mediators; D053583:Interleukin-1beta; D047428:Protein Kinase Inhibitors; D009569:Nitric Oxide; D048051:p38 Mitogen-Activated Protein Kinases; D015232:Dinoprostone