FNDC4 Inhibits RANKL-Induced Osteoclast Formation by Suppressing NF-κB Activation and CXCL10 Expression

Figure 4

FNDC4 inhibited RANKL-induced NF-κB activity. (a) BMMs were cultured with M-CSF (30 ng/mL) and RANKL (100 ng/mL) in the presence of FNDC4 (1000 ng/mL) for indicated times. The total cellular lysates were subject to western blotting analysis and immunoblotted with indicated antibodies. (b) The grey level of p-P65 was analyzed by being normalized to total P65. (c) The grey level of p-IκB-α was analyzed by being normalized to β-actin. (d) RAW 264.7 cells were stably transfected with luciferase reporter constructs controlled by NF-κB binding promoter elements. Cells plated in a 48-well plate were pretreated with different concentrations of FNDC4 (100 ng/mL, 500 ng/mL, and 1000 ng/mL) for 1 hour, followed by stimulation with RANKL (100 ng/mL) for another 8 hours; then the luciferase activity was measured. Data were presented as . and compared with the RANKL group.

(a)

(b)

(c)

(d)