Skip to main content
Fig. 3 | Molecular Medicine

Fig. 3

From: Deficiency of sphingomyelin synthase 1 but not sphingomyelin synthase 2 reduces bone formation due to impaired osteoblast differentiation

Fig. 3

Decreased bone formation in adult Sp7-Cre;SMS1f/f;SMS2−/− mice. a Hematoxylin-eosin staining of the distal femurs of 15-week-old C57BL/6, SMS1f/f;SMS2−/−, Sp7-Cre;SMS1+/+;SMS2+/−, and Sp7-Cre;SMS1f/f;SMS2−/− mice (scale bar 200 μm). b Quantitative analysis of width of the growth plate in C57BL/6, SMS1f/f;SMS2−/−, Sp7-Cre;SMS1+/+;SMS2+/−, and Sp7-Cre;SMS1f/f;SMS2−/− mice. c Calcein double-labeling at an interval of 3 days of femurs of 15-week-old C57BL/6, SMS1f/f;SMS2−/−, Sp7-Cre;SMS1+/+;SMS2+/−, and Sp7-Cre;SMS1f/f;SMS2−/− mice. The distance between two calcein-labeled mineralization fronts is indicated by red arrow heads at the midshaft of femurs (left). Von Kossa staining of the distal femurs of 15-week-old C57BL/6, SMS1f/f;SMS2−/−, Sp7-Cre;SMS1+/+;SMS2+/−, and Sp7-Cre;SMS1f/f;SMS2−/− mice. Undemineralized sections of the femurs of Sp7-Cre;SMS1f/f;SMS2−/− mice show that there is little trabecular interconnection (middle), that bone mass is almost normal, and that there is extensive accumulation of osteoid (right). Mineralized bone is stained black, unmineralized osteoid is stained in red. Osteoid is indicated by white arrow heads. d Histomorphometric analysis of the femurs of 15-week-old C57BL/6, SMS1f/f;SMS2−/−, Sp7-Cre;SMS1+/+;SMS2+/−, Sp7-Cre;SMS1+/+;SMS2−/−, and Sp7-Cre;SMS1f/f;SMS2−/− mice. MAR, mineral apposition rate; BFR/BS, bone formation rate/bone surface; MS/BS, mineralizing surface/bone surface; OV/OB, osteoid volume/bone volume; OS/BS, osteoid surface/bone surface; Ob.S/BS, Osteoblast surface/bone surface; ES/BS, eroded surface/bone surface; N.Oc/B.Pm, Osteoclast numbers/osteoclast perimeter; Oc.S/BS, osteoclast surface/bone surface; *, p < 0.05 versus C57BL/6, SMS1f/f;SMS2−/−, Sp7-Cre;SMS1+/+;SMS2+/−, and Sp7-Cre;SMS1+/+;SMS2−/−; mean ± SD, n = 8–10 for each genotype. e Relative abundance of gene expression of calvarial bone from C57BL/6, SMS1f/f;SMS2−/−, Sp7-Cre;SMS1+/+;SMS2+/−, Sp7-Cre;SMS1+/+;SMS2−/−, and Sp7-Cre;SMS1f/f;SMS2−/− mice. Significant downregulation of COL1A1, ALP, OCN, OPN, and BSP expression was observed in Sp7-Cre;SMS1f/f;SMS2−/− mice. f Relative abundance of RANK, RANKL, and OPG expression and the RANKL/OPG ratio for each mouse. Quantitative analysis of RT-PCR using RNA from p5 calvarial bone. Mean ± SD, *p < 0.05 versus C57BL/6, SMS1f/f;SMS2−/− and Sp7-Cre;SMS1+/+;SMS2+/−, **p < 0.005 versus C57BL/6 and Sp7-Cre;SMS1+/+;SMS2+/−; n = 10 for each genotype

Back to article page