Figure 1.

Butyrate and proprionate inhibit osteoclast differentiation in vitro. (A) Osteoclasts were differentiated from equivalent numbers of bone marrow derived macrophages (BMDM) in the presence of M-CSF and RANKL. GPR41, GPR109, and GPR43 expression was assessed by real-time PCR in osteoclast cultures before, 24 h, or 48 h after addition of RANKL. Gene expression was normalized to Hprt. (B) Equal numbers of BMDM were treated with acetate, proprionate, and butyrate at the indicated concentrations in the presence of RANKL and M-CSF and TRAP positive multinuclear cell (MNC) were counted. Representative TRAP stained are shown. (C) 200 μM of individual SCFA were added before, 24 h, or 48 h after addition of RANKL and TRAP positive MNC were counted. Data are shown as mean ± SEM. Difference between groups are determined by one-way ANOVA. * P < 0.05; ** P < 0.01; *** P < 0.001.