Fig. 4

Comparison of BMSC proliferation and osteogenic differentiation between aged osteoporotic rats in the loading and unloading groups. A Comparison of proliferation ability at each time point; the proliferation ability of the loading group was lower than that of the unloading group on the first day, and the ability then gradually increased until there was no significant difference. B Osteogenic induction of BMSCs was performed for 14 days. Representative images of Alizarin Red staining show the widespread distribution of calcium salt deposits (red). C Compared with those in the unloading group, the mRNA expression levels of ALP, OCN, Collagen I, and RUNX2 in the BMSCs of rats in the loading group were significantly lower than those in the unloading group. D The BMSC expression levels of collagen I and RUNX2 in the loading group were lower than those in the unloading group. The data are expressed as the mean ± SEM. **P < 0.01, ****P < 0.0001 vs. the unloading group