Fig. 2

Resveratrol and curcumin inhibit U0126-induced stimulation of activated caspase-3 and degradation of integrin in primary chondrocytes. Serum-starved human articular chondrocytes were either stimulated for 0, 12, 24, 36, 48 h with 10 ng/ml IL-1β, 1 μM U0126 or pre-treated with 10 μM resveratrol and 10 μM curcumin for 4 h followed by 0-, 12-, 24-, 36-, 48-h stimulation with 10 ng/ml IL-1β or 1 μM U0126. Equal amounts (500 ng protein per lane) of total proteins were separated by 12 and 7.5% SDS-PAGE followed by immunoblotting with anti-active caspase-3 and anti-β1-integrin antibodies. A time-dependent downregulation of β1-integrin and stimulation of activated caspase-3 expression was observed. In contrast, pre-treatment with resveratrol and curcumin resulted in a time-dependent increase in β1-integrin expression and inhibition of activated caspase-3. Synthesis of the housekeeping protein β-actin remained unaffected. Data shown are representative of three independent experiments