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Overexpression of DMP1 accelerates mineralization and alters cortical bone biomechanical properties in vivo.

ABSTRACT: Dentin matrix protein-1 (DMP1) is a key regulator of biomineralization. Here, we examine changes in structural, geometric, and material properties of cortical bone in a transgenic mouse model overexpressing DMP1. Micro-computed tomography and three-point bending were performed on 90 femora of wild type and transgenic mice at 1, 2, 4, and 6 months. Fourier transform infrared imaging was performed at 2 months. We found that the transgenic femurs were longer (p<0.01), more robust in cross-section (p<0.05), stronger (p<0.05), but had less post-yield strain and displacement (p<0.01), and higher tissue mineral density (p<0.01) than the wild type femurs at 1 and 2 months. At 2 months, the transgenic femurs also had a higher mineral-to-matrix ratio (p<0.05) and lower carbonate substitution (p<0.05) compared to wild type femurs. These findings indicate that increased mineralization caused by overexpressing DMP1 led to increased structural cortical bone properties associated with decreased ductility during the early post-natal period.

SUBMITTER: Bhatia A

PROVIDER: S-EPMC3222863 | biostudies-literature | 2012 Jan

REPOSITORIES: biostudies-literature

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Overexpression of DMP1 accelerates mineralization and alters cortical bone biomechanical properties in vivo.

Bhatia Ankush A Albazzaz Michael M Espinoza Orías Alejandro A AA Inoue Nozomu N Miller Lisa M LM Acerbo Alvin A George Anne A Sumner Dale R DR

Journal of the mechanical behavior of biomedical materials 20110929 1

Dentin matrix protein-1 (DMP1) is a key regulator of biomineralization. Here, we examine changes in structural, geometric, and material properties of cortical bone in a transgenic mouse model overexpressing DMP1. Micro-computed tomography and three-point bending were performed on 90 femora of wild type and transgenic mice at 1, 2, 4, and 6 months. Fourier transform infrared imaging was performed at 2 months. We found that the transgenic femurs were longer (p<0.01), more robust in cross-section ( ...[more]

PMID: 22100074

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Dataset Information

Overexpression of DMP1 accelerates mineralization and alters cortical bone biomechanical properties in vivo.

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Overexpression of DMP1 accelerates mineralization and alters cortical bone biomechanical properties in vivo.

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