Table 6.
Femoral Microarchitecture Assessed by μCT of 2-Month–Old Notch2tm1.1ECan Mutant Mice and Sex-Matched Control Littermates Subjected to Splenectomies or Sham Interventions
| Males | Sham |
Splenectomy |
||
|---|---|---|---|---|
| Control (n = 6) | Notch2tm1.1ECan (n = 5) | Control (n = 7) | Notch2tm1.1ECan (n = 4) | |
| Distal femur trabecular bone | ||||
| Bone/total volume, % | 8.8 ± 2.7 | 5.2 ± 3.2 | 11.1 ± 3.5 | 4.0 ± 2.9∗ |
| Trabecular separation, μm | 207 ± 11 | 281 ± 39∗ | 201 ± 36 | 333 ± 79∗ |
| Trabecular no., 1/mm | 4.9 ± 0.3 | 3.7 ± 0.6∗ | 5.1 ± 0.8 | 3.2 ± 0.8∗ |
| Trabecular thickness, μm | 39 ± 6 | 35 ± 7 | 44 ± 5 | 32 ± 6∗ |
| Connectivity density, 1/mm3 | 215 ± 71 | 123 ± 105 | 269 ± 83 | 85 ± 76∗ |
| Structure-model index | 2.8 ± 0.3 | 3.1 ± 0.4 | 2.7 ± 0.3 | 3.1 ± 0.5∗ |
| Density of material, mg HA/cm3 | 855 ± 18 | 819 ± 26∗ | 867 ± 25 | 800 ± 29∗ |
| Femoral midshaft cortical bone | ||||
| Bone/total volume, % | 87.5 ± 1.3 | 83.9 ± 4.6∗ | 87.8 ± 1.6 | 83.8 ± 2.6∗ |
| Porosity, % | 12.5 ± 1.3 | 16.1 ± 4.6∗ | 12.2 ± 1.6 | 16.2 ± 2.6∗ |
| Cortical thickness, μm | 148 ± 13 | 119 ± 21∗ | 152 ± 11 | 116 ± 13∗ |
| Total area, mm2 | 1.8 ± 0.3 | 1.6 ± 0.3 | 1.9 ± 0.2 | 1.7 ± 0.2∗ |
| Bone area, mm2 | 0.8 ± 0.1 | 0.6 ± 0.1∗ | 0.8 ± 0.1 | 0.6 ± 0.1∗ |
| Periosteal perimeter, mm | 4.8 ± 0.3 | 4.4 ± 0.5 | 4.9 ± 0.3 | 4.7 ± 0.3∗ |
| Endocortical perimeter, mm | 3.6 ± 0.2 | 3.4 ± 0.3 | 3.7 ± 0.3 | 3.7 ± 0.3 |
| Density of material, mg HA/cm3 | 1119 ± 16 | 1093 ± 35 | 1123 ± 21 | 1083 ± 22∗ |
| Females | Sham |
Splenectomy |
||
|---|---|---|---|---|
| Control (n = 5) | Notch2tm1.1ECan (n = 5) | Control (n = 4) | Notch2tm1.1ECan (n = 6) | |
| Distal femur trabecular bone | ||||
| Bone/total volume, % | 5.5 ± 1.0 | 2.6 ± 1.1∗ | 4.8 ± 1.4 | 2.9 ± 1.6∗ |
| Trabecular separation, μm | 261 ± 20 | 355 ± 72 | 272 ± 57 | 402 ± 109 |
| Trabecular no., 1/mm | 3.9 ± 0.3 | 2.9 ± 0.6∗ | 3.8 ± 0.7 | 2.7 ± 0.7∗ |
| Trabecular thickness, μm | 35 ± 2 | 29 ± 3∗ | 33 ± 1 | 30 ± 3 |
| Connectivity density, 1/mm3 | 158 ± 56 | 57 ± 37∗ | 118 ± 54 | 69 ± 44 |
| Structure-model index | 2.8 ± 0.2 | 3.1 ± 0.2 | 3.0 ± 0.1 | 3.0 ± 0.2 |
| Density of material, mg HA/cm3 | 843 ± 16 | 825 ± 7 | 844 ± 16 | 813 ± 24∗ |
| Femoral midshaft cortical bone | ||||
| Bone/total volume, % | 87.1 ± 0.8 | 84.1 ± 3.0 | 85.7 ± 2.2 | 79.9 ± 7.0 |
| Porosity, % | 12.9 ± 0.8 | 15.9 ± 3.0 | 14.3 ± 2.2 | 20.1 ± 7.0 |
| Cortical thickness, μm | 136 ± 10 | 119 ± 18 | 128 ± 14 | 101 ± 23∗ |
| Total area, mm2 | 1.6 ± 0.1 | 1.4 ± 0.1∗ | 1.5 ± 0.1 | 1.5 ± 0.1 |
| Bone area, mm2 | 0.7 ± 0.1 | 0.6 ± 0.1∗ | 0.6 ± 0.1 | 0.5 ± 0.1∗ |
| Periosteal perimeter, mm | 4.4 ± 0.1 | 4.1 ± 0.2∗ | 4.4 ± 0.1 | 4.3 ± 0.2 |
| Endocortical perimeter, mm | 3.4 ± 0.1 | 3.1 ± 0.3 | 3.4 ± 0.1 | 3.4 ± 0.3 |
| Density of material, mg HA/cm3 | 1123 ± 9 | 1099 ± 47 | 1111 ± 20 | 1057 ± 43∗ |
Notch2tm1.1ECan and control sex-matched littermates were subjected to splenectomies or sham interventions at 1 month of age and sacrificed 1 month later for analysis. μCT was performed at the femoral distal end for trabecular or midshaft for cortical bone. Data are expressed as means ± SD of biological replicates.
μCT, microcomputed tomography; HA, hydroxyapatite.
∗
P < 0.05 versus control mice (two-way analysis of variance with Holm-Šídák post-hoc analysis).