Fig. 3

Bhlhe40 deficiency impairs bone resorption in mice. A, B Mechanical strength and quantification of femurs between Wt and Bhlhe40^−/− mice at 4 weeks (n = 4). C Micro CT and three-dimensional (3D) reconstruction models of the femoral bone trabecula and cortical of Wt and Bhlhe40^−/− mice (4 weeks) (Scale bar, 1 mm). D Quantification of bone parameters by Micro CT from Wt and Bhlhe40^−/− mice (4 weeks) (n = 5). Bone volume fraction (BV/TV); Number of trabeculae (Tb. N); Trabecular bone thickness (Tb. Th); Trabecular bone separation (Tb. Sp); Bone mineral density (BMD); Cortical bone thickness (Ct. Th.) E, F H&E and TRAP staining of femur sections from Wt and Bhlhe40^−/− mice (4 weeks). The yellow arrowhead points to OCs (Scale bar, 150 um). G Immunohistochemistry of RANK in femurs from Wt and Bhlhe40^−/− mice at 4 weeks (Scale bar, 50 μm). H RNA expression of OC-specific genes in BMMs from Wt and Bhlhe40^−/− mice (RANK: n = 4; Others: n = 6). I, J TRAP staining and quantification (n = 5) of OCs from Wt and Bhlhe40^−/− mice (Scale bar, 50 μm). (K) Phalloidin staining of OCs from Wt and Bhlhe40^−/− mice (Scale bar, 50 μm). All data are mean ± SD; * P < 0.05, ** P < 0.01, *** P < 0.001. by unpaired Student’s t test