Regulation of nitric oxide and prostaglandin E2 production by CSAIDSTM (SB203580) in murine macrophages and bovine chondrocytes stimulated with LPS

Abstract.

Objective and Design: To compare two anti-inflammatory drugs: CSAIDS^TM (SB 203580) 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 μM CSAIDS^TM or 10 μM of hydrocortisone before stimulating them with 1-100 μg/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^TM (1 μM) inhibited the production of NO and PGE₂ (p ≤ 0.01) in bovine chondrocytes, but not in murine macrophages (RAW 264.7) (p ≤ 0.1). In fact, CSAIDS^TM (in murine macrophages) marginally augmented nitrite accumulation (∼ 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^TM, although hydrocortisone and CSAIDS^TM inhibit PGE₂ accumulation. Hydrocortisone inhibited both PGE₂ and NO production significantly (p ≤ 0.01) in murine macrophages. Furthermore, hydrocortisone significantly inhibited (p ≤ 0.01) PGE₂ but marginally (p ≤ 0.05) NO in bovine chondrocytes.¶Conclusion: These experiments demonstrate differential action of CSAIDS^TM and hydrocortisone on NO and PGE₂ production in bovine chondrocytes and RAW 264.7 cells.