2007 Fiscal Year Final Research Report Summary
Osteocyte functions in osteoporosis of underused bone. Establishing a rat underuse model and its application to the analysis of drug effect
| Project/Area Number |
18592075
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Pathobiological dentistry/Dental radiology
|
|---|
| Research Institution | Kanagawa Dental College |
|---|
Principal Investigator |
TAKAGAKI Yuko Kanagawa Dental College, Department of Functional Biology, Associate Professor (60050689)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
KASHIMA Isamu Kanagawa Dental College, Department of Maxillofacial Diagnostic Science, Professor (00130914)
|
|---|
| Project Period (FY) |
2006 – 2007
|
| Keywords | osteoporosis / disuse osteoporosis / restraint / (osteocyte) lacuna / osteocytes / confocal Raman spectroscopy / bone strength / fracture |
|---|
| Research Abstract |
Lack of estrogen after menopause and reduced activity (hypokinesis) are both important factors in the pathogenesis of osteoporosis in the elderly women. To compare the contribution of these two factors independently, we developed an animal model of ovariectomized (OVX) and sham-operated rats, which were housed in cages with limited space. The experimental cages restricted standing and walking, while allowing other activities such as eating, drinking and changing positions. After sacrificing rats at week 12, femora and tibia were examined with peripheral quantitative computed tomography (pQCT), laser Raman spectroscopy, three point bending, and histopathology. Although significantly elevated levels of metabolic markers, CTx, and osteocalcin were recorded in OVX groups compared to the Sham groups, results of bone strength as well as geometric parameters revealed significant differences only between Sham and Restricted groups. In the Restricted rat tibial cortices, both the number of empty osteocytic lacunae and lacuno-canalicular sclerostin staining were significantly increased. Not only was the bone thinner, narrowed marrow space was accompanied by the increased endocortical bone formation rate. Osteoclast activity was not necessarily associated with the osteoporotic pathology in the restrained rat bones. The uncoupling of osteoblastic and osteoclastic activities as well as the disorganized osteocyte network suggests a predominant role of osteocytic control over the cortical bone loss in the sedentary individuals. This model proved useful in evaluating the effect of drugs on bone by showing synergy between PTH and walking. The uneven outward extension of cortical bone was suggested from the local variation in the intensity of the synergistic effect.
|
Research Products
(28 results)
-
-
-
[Journal Article] Low-intensity pulsed ultrasound accelerates periodontal wound healing after flap surgery.2008
Author(s)
Ikai H, Tamura, T., Watanabe, T., Itou, M., Sugaya, A., Iwabuchi, T., Mikuni-Takagaki, Y., Deguchi, S.
-
Journal Title
Journal of Periodontal Research 43
Pages: 212-216
Description
「研究成果報告書概要(欧文)」より
-
-
-
-
-
-
-
[Journal Article] A crucial role for MMP-2 in osteocytic canalicular formation and bone metabolism.2006
Author(s)
Inoue K, Mikuni-Takagaki Y, Oikawa K, Itoh T, Inada M, Noguch, T, Park JS, Onodera, T, Krane SM, Noda M, Itohara S
-
Journal Title
Journal of Biological Chemistry 281
Pages: 33814-33824
Description
「研究成果報告書概要(欧文)」より
-
[Journal Article] αVβ3 integrin ligands enhance volume-sensitive calcium influx in mechanically stretched osteocytes.2006
Author(s)
Miyauchi A, Gotoh M, Kamioka H, Notoya K, Sekiya H, Takagi Y, Yoshimoto Y, Ishikawa H, Chihara K, Takano-Yamamoto T, Fujita T, Mikuni-Takagaki Y
-
Journal Title
Journal of Bone and Mineral Metabolism 24
Pages: 498-504
Description
「研究成果報告書概要(欧文)」より
-
-
-
-
-
[Presentation] Abnormal tibial torsion may cause an earliest detectable deformity in STR Ort Crlj osteoarthritis mouse model2007
Author(s)
Naruse, K., et. al.
Organizer
6th Combined Meeting of the Orthopedic Research Societies of Australia, Britain, Canada, Europe, Japan, Korea, Taiwan, USA
Place of Presentation
Honolulu,USA
Year and Date
2007-10-23
Description
「研究成果報告書概要(和文)」より
-
[Presentation] Osteocyte specific survival through freeze-thaw and-80℃ storage in unprocessed rat long bones2007
Author(s)
Ohashi, M., et. al.
Organizer
6th Combined Meeting of the Orthopedic Research Societies of Australia, Britain, Canada, Europe, Japan, Korea, Taiwan, USA
Place of Presentation
Honolulu,USA
Year and Date
2007-10-23
Description
「研究成果報告書概要(和文)」より
-
[Presentation] Abnormal tibial torsion may cause an earliest detectable deformity in STR Ort Crlj osteoarthritis mouse model.2007
Author(s)
Naruse K, Urabe K, Mikuni-Takagaki Y, Itoman M
Organizer
6th Combined Meeting of the Orthopedic Research Societies of Australia/New Zealand, Britain, Canada, Europe
Place of Presentation
Japan, Korea, Taiwan, and USA, Honolulu
Year and Date
2007-10-23
Description
「研究成果報告書概要(欧文)」より
-
[Presentation] Osteocyte-specific survival thrdugh freeze-thaw and-80oC storage in unprocessed rat long bones.2007
Author(s)
Ohashi M, Urabe K, Naruse K, Mikuni-Takagaki Y, Itoman M
Organizer
6th Combined Meeting of the Orthopedic Research Societies of Australia/New Zealand, Britain, Canada, Europe
Place of Presentation
Japan, Korea, Taiwan, and USA, Honolulu
Year and Date
2007-10-23
Description
「研究成果報告書概要(欧文)」より
-
-
-
-
-
-
-
-
-
