Figure 1

Treatment with r-Irisin prevents bone loss in femurs from hindlimb-suspended mice. (a) Contact radiographs of selected long bones from normal loading mice (Rest veh-inj) and unloaded mice treated with vehicle or recombinant Irisin (r-Irisin, 100 µg kg⁻¹ per week for 28 days, mice were sacrificed 24 hours after last dose). Arrows indicate difference in radiodensity between femur of unloaded mice treated with vehicle and femur of unloaded mice treated with recombinant Irisin. (b) Representative micro-CT-generated section images and calculated cortical and trabecular parameters of femurs harvested from Rest mice vehicle- or Irisin-injected and Unload mice vehicle- or r-Irisin-injected. Cortical bone parameters included bone mineral density (BMD) and cortical thickness (Ct.Th). Trabecular bone parameters included bone mineral density (BMD), bone volume/total volume (BV/TV), trabecular number (Tb.N), trabecular thickness (Tb.Th), trabecular separation (Tb Sp) and Fractal Dimension. Data are presented as mean ± SEM. n = 7–8 mice per group. All data were normally distributed according to the Shapiro-Wilk normality test and analyzed by one-way ANOVA and Bonferroni’s post hoc analysis. Cohen’s d values were measured for non-significant differences of results and can be found as Supplementary Table S1. *p ≤ 0.05, **p ≤ 0.01 versus Rest vehicle-injected mice. ^{^} p ≤ 0.05, ^{^^} p ≤ 0.01 versus Unload vehicle-injected mice.