Fig. 7

MG-CM promoted bone fracture repair in vivo. a The regenerative bone in fracture areas was detected by micro-CT at postoperative 2 weeks. b Quantitative analysis of BV/TV of regenerative tissues in fracture areas. c H&E staining and Masson’s trichrome staining were performed to observe the histological structures of regenerative tissues. d, e Immunohistochemistry staining was employed to detect the expression of OCN in the newly formed bone followed by quantitative analysis. Abbreviations: NG-CM, conditioned media from endothelial progenitor cells under normal gravity; MG-CM, conditioned media from endothelial progenitor cells under microgravity; BV/TV, bone volume per tissue volume; H&E, hematoxylin and eosin; OCN, osteocalcin. Data were presented as the mean ± standard deviation. *P < 0.05, **P < 0.01, and ***P < 0.001