Orientation of mineral crystallites and mineral density during skeletal development in mice deficient in tissue non-specific alkaline phosphatase
| Autor: | T Vandenbos, W Beertsen, P Roschgr, Peter Fratzl, Nadja Fratzl-Zelman, W Tesch, Klaus Klaushofer |
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| Přispěvatelé: | Parodontologie (OUD, ACTA) |
| Rok vydání: | 2003 |
| Předmět: |
Endocrinology
Diabetes and Metabolism Sialoglycoproteins Long bone Mutant Osteocalcin Bone Matrix Mineralization (biology) Collagen Type I Bone remodeling Immunolabeling Mice Calcification Physiologic Bone Density medicine Animals Orthopedics and Sports Medicine Osteopontin Mice Knockout Minerals Bone Development biology Chemistry Anatomy Alkaline Phosphatase Cell biology medicine.anatomical_structure biology.protein Cortical bone Crystallization |
| Zdroj: | Journal of Bone and Mineral Research, 18, 117-125. Wiley-Blackwell Tesch, W, van den Bos, T, Roschgr, P, Fratzl-Zelman, N, Klaushofer, K, Beertsen, W & Fratzl, P 2003, ' Orientation of mineral crystallites and mineral density during skeletal development in mice deficient in tissue non-specific alkaline phosphatase ', Journal of Bone and Mineral Research, vol. 18, pp. 117-125 . https://doi.org/10.1359/jbmr.2003.18.1.117 Journal of Bone and Mineral Research, 18, 117-125. American Society for Bone and Mineral Research |
| ISSN: | 0884-0431 |
| Popis: | Tissue nonspecific alkaline phosphatase (TNALP) is thought to play an important role in mineralization processes, although its exact working mechanism is not known. In the present investigation we have studied mineral crystal characteristics in the developing skeleton of TNALP-deficient mice. Null mutants (n = 7) and their wild-type littermates (n = 7) were bred and killed between 8 and 22 days after birth. Skeletal tissues were processed to assess mineral characteristics (small angle X-ray scattering, quantitative backscattered electron imaging), and to analyze bone by light microscopy and immunolabeling. The results showed a reduced longitudinal growth and a strongly delayed epiphyseal ossification in the null mutants. This was accompanied by disturbances in mineralization pattern, in that crystallites were not orderly aligned with respect to the longitudinal axis of the cortical bone. Among the null mutants, a great variability in the mineralization parameters was noticed. Also, immunolabeling of osteopontin (OPN) revealed an abnormal distribution pattern of the protein within the bone matrix. Whereas in the wild-type animals OPN was predominantly observed in cement and reversal lines, in the null mutants, OPN was also randomly dispersed throughout the nonmineralized matrix, with focal densities. In contrast, the distribution pattern of osteocalcin (OC) was comparable in both types of animals. It is concluded that ablation of TNALP results not only in hypomineralization of the skeleton, but also in a severe disorder of the mineral crystal alignment pattern in the corticalis of growing long bone in association with a disordered matrix architecture, presumably as a result of impaired bone remodeling and maturation. |
| Databáze: | OpenAIRE |
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