Figure 7.

Luciferase activity of transcriptional factors during cytokine-stimulated osteoclastogenesis. (A) All the cytokines induced enhanced NF-κB activity, although the patterns were different. RANKL, IL-1β and IL-23 induced peak level of luciferase activity of NF-κB at 6 h after administration of these cytokines. The peak level of NF-κB luciferase activity was shown at 12 h after IL-6 administration. In TNF-α and IL-17, NF-κB activity reached peak levels at 24 h. (B) The luciferase activity of AP-1 was increased only at 6 h after TNF-α administration. (C) The luciferase activity of NFAT showed a tendency to be decreased by the stimulation with cytokines, except IL-23 at 6 h and IL-1β at 12 h. (D) The luciferase activity of CREB was increased only at 6 h after the IL-23 challenge. Other cytokines appeared to reduce CREB activity.