Chondroprotective Effect of Cynaroside in IL-1β-Induced Primary Rat Chondrocytes and Organ Explants via NF-κB and MAPK Signaling Inhibition

Figure 5

Effects of cynaroside on IL-1β-induced activation of NF-κB and phosphorylation of MAPKs in primary rat chondrocytes. Cells were pretreated with cynaroside (40, 80, and 160 μM) for 1 h, followed by IL-1β (10 ng/mL) stimulation for 1 h. (a) Phosphorylation levels of IκB-α and NF-κB p65 translocation to the nucleus were determined using western blot analysis. (b, c) Quantitative data of (a) were analyzed using ImageJ software. (d) Protein levels of phosphorylation of MAPKs (ERK, JNK, and p38) were determined using western blot analysis. (e) Quantitative data of (d) were analyzed using ImageJ software. α-Tubulin and lamin B1 were used as cytosolic and nuclear internal controls, respectively. ^## compared with the control group; , , and compared with the IL-1β-treated group. CON: control; IκB-α: nuclear factor of kappa light polypeptide gene enhancer in B-cell inhibitor, alpha; p65: NF-kappa-B p65 subunit; ERK: extracellular signal-regulated kinase; JNK: c-Jun N-terminal kinase.

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