Figure 4.

Effect of cynaroside on IL-1β-induced collagen type II and aggrecan in primary rat chondrocytes. (a) Cells were pretreated with cynaroside (40, 80, and 160 μM) for 1 h, followed by IL-1β (10 ng/mL) stimulation for 24 h. Collagen type II and aggrecan were measured in cultured medium using ELISA. Results are represented as mean ± SD of three independent experiments. ^##p < 0.01 compared with the control group; ^∗p < 0.05 and ^∗∗p < 0.01 compared with the IL-1β-treated group. CON: control. (b) Cells were pretreated with cynaroside (40, 80, and 160 μM) for 1 h, followed by IL-1β (10 ng/mL) stimulation for 48 h. Proteoglycan contents were determined using Alcian Blue stain.