Fig. 1

Ex-4 synergizes with ED-71 to stimulate bone formation and reduce the blood glucose levels in db/db mice. A Typical three-dimensional and two-dimensional coronal images of tibia were obtained by Micro-CT. B HE staining. Bar, 500 μm. C The bone volume/tissue volume, trabeculae bone number, trabeculae bone thickness and trabeculae bone space were further analyzed in HE staining (n = 4). D and E Immunohistochemistry of ALP (arrows) (D) and immunohistochemistry of Col I (brown color) (E). Bar, 100 μm. F Immunoreactivity quantitative evaluation of ALP and Col I. G Serum calcium and phosphorus levels (n = 4). H Comparison of blood glucose levels between WT and db/db mice, and changes in blood glucose of each group during the treatment (n = 4). I HE staining. Bar, 200 μm. Values are expressed as mean ± standard deviation, *p < 0.05, **p < 0.01, ***p < 0.001. CON control, Ex-4 exendin-4, ED-71 eldecalcitol, Ex-4 + ED-71 exendin-4 + eldecalcitol, WT wild-type mice, BV/TV bone volume/tissue volume, Tb.N trabeculae bone number, Tb.Th trabeculae bone thickness, Tb.Sp Trabeculae bone space, ALP alkaline phosphatase, Col I collagen I