Figure 3: GDF11 stimulates RANKL-induced osteoclastogenesis.
(a) Representative TRAP staining of the BMMs after 4 days of osteoclast differentiation. 100 ng ml−1 M-CSF was present in all settings. Scale bar, 100 μm. (b,c) Osteoclast number and size. TRAP-positive cells with at least three nuclei were counted as osteoclasts. Results are shown as mean±s.d.; n=9; *P<0.05, **P<0.01 and ***P<0.001 by analysis of variance (ANOVA) with Tukey’s post hoc test. (d,e) Cell proliferation and apoptosis assay. BMMs were cultured in the presence of 100 ng ml−1 M-CSF and 50 ng ml−1 RANKL with indicated amount of rGDF11 for 2 days. Results are shown as mean±s.d.; n=8. (f) Representative images of resorption pits on Osseo Assay surface after 7 days of culture. Scale bar, 100 μm. (g,h) Resorption pits number and resorption area. Results are shown as mean±s.d.; n=8; **P<0.01 and ***P<0.001 by ANOVA with Tukey’s post hoc test. (i) Representative images of osteoclasts in co-cultures with osteoblasts in presence of 1,25(OH)2D3 and PGE2 with indicated amount of rGDF11 for 5 days. Scale bar, 100 μm. (j,k) Osteoclast number and size for the co-cultures. Results are shown as mean±s.d.; n=8. *P<0.05 and ***P<0.001 by ANOVA with Tukey’s post hoc test.
