Fig 1.
Effects of W9 and risedronate administration on alveolar bone loss in OPG-/- mice.
(A) Experimental design. W9 or vehicle was administered subcutaneously three times/day for the first 5 days to 12-week-old male OPG–/–mice. Risedronate was administered once a day at 0.1 mg/kg body weight for the first 3 days. Saline (vehicle) was administered to OPG–/– and WT mice similarly to W9 administration. Each group of mice was sacrificed on day 6 (n = 7). (B) Three-dimensional μCT images of maxillae from WT mice and OPG–/–mice. (C) A schematic diagram for measurement of the distance between CEJ and ABC on μCT images. (D) The CEJ-ABC distance in WT mice and in OPG–/–mice. (E) μCT images of the interradicular septum of the first molar (M1) in mandibles from WT mice (an area surrounded by a white dotted line) and OPG–/–mice. (F) Bone volume/tissue volume (BV/TV) was measured in the M1 interradicular septum from WT mice and in OPG–/–mice treated with or without W9 and risedronate (n = 7). Data are expressed as the mean ± SD in (D) and (F). *: p<0.05. Scale bar, 0.5 mm.
Fig 2.
Effects of W9 and risedronate administration on alveolar bone resorption in OPG-/- mice.
(A) Histological analysis of the interradicular septum of the first molar (M1) in mandibles from WT mice and OPG–/–mice treated with and without W9 or risedronate. Mandible tissues were subjected to Villanueva bone staining. (B) Osteoclasts in the M1 interradicular septum from WT and OPG–/–mice. Multinucleated osteoclasts are surrounded by white dotted lines. (C) TRAP staining of maxillae from WT and of OPG–/–mice. TRAP-positive osteoclasts (red cells) were observed in the M1 interradicular septum in alveolar bone areas. (D) The number of TRAP-positive cells/bone surface (N/mm) was determined in the M1 interradicular septum (n = 5). Data are expressed as the means ± SD. *: p<0.05. Scale bar, 50 μm.
Table 1.
Histomorphometric analysis of the protective effects of W9 on alveolar bone loss in OPG-/- mice.
Fig 3.
Effects of W9 and risedronate administration on alveolar bone formation in OPG-/- mice.
(A) Histological analysis of the interradicular septum of the first molar (M1) in mandibles from WT and OPG–/–mice treated with and without W9 or risedronate. Mandible tissues were subjected to Villanueva bone staining. Mature osteoblasts were indicated by arrows. (B) Osterix staining of maxillae from WT and OPG–/–mice. Osterix-positive cells in nuclei (brown, arrows) were observed in the M1 interradicular septum in alveolar bone areas. (C) The number of osterix-positive cells/bone surface (N/mm) was determined in the M1 interradicular septum (n = 5). (D) ALP staining of maxillae from WT and OPG–/–mice. ALP-positive cells were observed in the M1 interradicular septum in alveolar bone areas. (E) Serum ALP activities were measured with an ALP kit (n = 7). Data are expressed as the mean ± SD in (C) and (E). *: p<0.05. Scale bar, 50 μm.
Fig 4.
Effects of W9 and risedronate administration on Wnt/β-catenin signaling of alveolar bone in OPG-/- mice.
(A) Histological analysis of the interradicular septum of the first molar (M1) in maxillae from WT and OPG–/–mice treated with and without W9 or risedronate. β-catenin staining of WT and OPG–/–mice. β-catenin-positive cells in nuclei (brown) were observed in the M1 interradicular septum in alveolar bone areas. (B) Sclerostin and TRAP double staining of WT and OPG–/–mice. Sclerostin-positive osteocytes (brown) were observed in the M1 interradicular septum in alveolar bone areas. Sclerostin-positive osteocytes are indicated by black arrows. (C) The number of sclerostin-positive cells/bone area (N/mm2) was determined in the M1 interradicular septum (n = 5). Data are expressed as the mean ± SD. *: p<0.05. Scale bar, 50 μm.