Objective and design: To compare two anti-inflammatory drugs: CSAIDS (SB203580) and hydrocortisone on iNOS and COX-2 expression.
Material or subjects: Murine macrophages and bovine chondrocytes stimulated with LPS and human OA-affected cartilage were used in this study.
Treatment: The macrophages and chondrocytes were preincubated (30 min) with 0.1-1.0 microM CSAIDS or 10 microM of hydrocortisone before stimulating them with 1-100 microg/ml LPS.
Methods: The end products of iNOS and COX-2: nitric oxide (NO) and PGE2 were estimated by Greiss method and RIA, respectively.
Results: CSAIDS (1 microM) inhibited the production of NO and PGE2 (p< or =0.01) in bovine chondrocytes, but not in murine macrophages (RAW 264.7) (p< or =0.1). In fact, CSAIDS (in murine macrophages) marginally augmented nitrite accumulation (approximately 20%) at 14-24 h of LPS stimulation. Western blot analysis of COX-2 in bovine chondrocytes show decrease in COX-2 expression by hydrocortisone but not CSAIDS, although hydrocortisone and CSAIDS inhibit PGE2 accumulation. Hydrocortisone inhibited both PGE2 and NO production significantly (p< or =0.01) in murine macrophages. Furthermore, hydrocortisone significantly inhibited (p< or =0.01) PGE2 but marginally (p< or =0.05) NO in bovine chondrocytes.
Conclusion: These experiments demonstrate differential action of CSAIDS and hydrocortisone on NO and PGE2 production in bovine chondrocytes and RAW 264.7 cells.