Biomechanical and Bone Material Properties of Schnurri‐3 Null Mice

JBMR Plus

Barbara M Misof¹  Paul Roschger¹  Jochen G Hofstaetter¹  Stéphane Blouin¹  Eleftherios P Paschalis¹  Klaus Klaushofer¹  Ruth Zoehrer¹  Richard Weinkamer²  Christiane Schueler³  Reinhold G Erben³  Dallas C Jones⁴ 

[1] 1st Medical Department Hanusch Hospital Ludwig Boltzmann Institute of Osteology at the Hanusch Hospital of WGKK and AUVA Trauma Centre Meidling Vienna Austria;Department of Biomaterials Max Planck Institute of Colloids and Interfaces Potsdam Germany;Department of Biomedical Sciences University of Veterinary Medicine Vienna Austria;Department of Immunology and Infectious Diseases Harvard School of Public Health Boston MA USA;

关键词: Shn3‐NULL MICE;    Shn3‐DEFICIENCY;    BONE BIOMECHANICS;    BONE MATERIAL QUALITY;    BONE MINERALIZATION;    DENSITY DISTRIBUTION;    COLLAGEN CROSS‐LINK RATIO;   

DOI  :  10.1002/jbm4.10226

来源: DOAJ

【 摘 要 】

ABSTRACT Schnurri‐3 (Shn3) is an essential regulator of postnatal skeletal remodeling. Shn3‐deficient mice (Shn3–/–) have high bone mass; however, their bone mechanical and material properties have not been investigated to date. We performed three‐point bending of femora, compression tests of L3 vertebrae. We also measured intrinsic material properties, including bone mineralization density distribution (BMDD) and osteocyte lacunae section (OLS) characteristics by quantitative backscatter electron imaging, as well as collagen cross‐linking by Fourier transform infrared microspectroscopy of femora from Shn3–/– and WT mice at different ages (6 weeks, 4 months, and 18 months). Moreover, computer modeling was performed for the interpretation of the BMDD outcomes. Femora and L3 vertebrae from Shn3–/– aged 6 weeks revealed increased ultimate force (2.2‐ and 3.2‐fold, p < .01, respectively). Mineralized bone volume at the distal femoral metaphysis was about twofold (at 6 weeks) to eightfold (at 4 and 18 months of age) in Shn3–/– (p < .001). Compared with WT, the average degree of trabecular bone mineralization was similar at 6 weeks, but increased at 4 and 18 months of age (+12.6% and +7.7%, p < .01, respectively) in Shn3–/–. The analysis of OLS characteristics revealed a higher OLS area for Shn3–/– versus WT at all ages (+16%, +23%, +21%, respectively, p < .01). The collagen cross‐link ratio was similar between groups. We conclude that femora and vertebrae from Shn3–/– had higher ultimate force in mechanical testing. Computer modeling demonstrated that in cases of highly increased bone volume, the average degree of bone matrix mineralization can be higher than in WT bone, which was actually measured in the older Shn3–/– groups. The area of 2D osteocyte lacunae sections was also increased in Shn3‐deficiency, which could only partly be explained by larger remnant areas of primary cortical bone. © 2019 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research.

【 授权许可】

Unknown