Fig. 1

Catalpol enhanced osteogenesis of BMSCs in vitro. a Catalpol chemical structure. b The effect of catalpol on BMSC proliferation was measured per CCK-8 assays. c, d Images and quantification of ALP activity after 7 days of osteogenic induction. e, f Calcium mineralization was assessed via ARS staining and quantification. g, h Western blot analysis of osteogenic-related proteins COL1A1, RUNX2, and OCN. All the experiments were repeated at least 3 times independently. The data are presented as means ± SEM. ^*p < 0.05, ^**p < 0.01 vs. control group, ^##p < 0.01 vs. 100 μM catalpol group