A–C: Effects of IGF-1 or/and PDGF-bb on the IL-1β-induced Akt activation in chondrocytes in monolayer cultures.

<p>Primary chondrocytes were either stimulated with 10 ng/ml IL-1β, pre-stimulated with 10 ng/ml IGF-1, 10 ng/ml PDGF-bb or a combination of both growth factors (5 ng/ml each) for 12 h and treated with 10 ng/ml IL-1β for the indicated times. Whole cell extracts were immunoprecipitated with anti-IKK-α antibody followed by western blot analysis using anti-Akt, anti-phospho-specific Akt and anti-IKK-α antibodies. The results shown are representative of three independent experiments.