FIGURE 6.
Influence of ePPi on the loss of phenotype induced by IL-1β. A, effect of ePPi on the activation of JNK pathway by IL-1β. Chondrocytes were stimulated with 10 ng/ml of IL-1β, in the presence and the absence of 0.1 mm of ePPi for the indicated times. Proteins were extracted and subjected to Western blotting using anti-phospho- and anti-total-JNK antibodies. Images presented are representative of three independent experiments. B, effect of SP600125 and ePPi on the dedifferentiating effects of IL-1β. Total RNA was extracted from chondrocytes challenged for 1 h with SP600125 (5 μm), then stimulated with 10 ng/ml of IL-1β in the presence and absence of 0.1 mm of ePPi. Total RNA was subjected to RT-qPCR analysis. The levels of mRNA of interest were normalized to that of S29 (used as reference gene). Results are presented in histograms as means (± S.D.) over S29 value (n = 3). Statistically significant differences from vehicle or vehicle + PPi are indicated as *, p < 0.05, and from cells stimulated with IL-1β and from cells stimulated with IL-1β + PPi as #, p < 0.05.