Effects of IGF-1 or/and PDGF-bb on IL-1β-induced NF-κB-dependent pro-inflammatory, pro-apoptotic and matrix degrading gene products in chondrocytes.

<p>To determine whether <i>IGF-1</i> or/and <i>PDGF-bb</i>exert effects on IL-1β-induced NF-κB-dependent expression of pro-inflammatory, pro-apoptotic and matrix degrading gene products, primary chondrocytes were either stimulated with 10 ng/ml IL-1β, 10 ng/ml PDGF-bb, 10 ng/ml IGF-1 or combination of both growth factors (5 ng/ml each) or pre-stimulated for 12 h with 10 ng/ml PDGF-bb, 10 ng/ml IGF-1 or combination of both growth factors (5 ng/ml each) followed by 10 ng/ml IL-1β for 24. Equal amounts of total proteins were separated by SDS-PAGE and analyzed by immunoblotting using antibodies raised against COX-2, MMP-9 and MMP-13 and active caspase-3. Stimulation with IL-1β resulted in production of COX-2, MMP-9, MMP-13 and caspase-3 cleavage. Pre-treatment with a combination of both IGF-1 or/and PDGF-bb downregulated COX-2, MMP-9, MMP-13 and cleaved caspase-3.