Increased trabecular bone and improved biomechanics in an osteocalcin-null rat model created by CRISPR/Cas9 technology
Osteocalcin, also known as bone γ-carboxyglutamate protein (Bglap), is expressed by osteoblasts and is commonly used as a clinical marker of bone turnover. A mouse model of osteocalcin deficiency has implicated osteocalcin as a mediator of changes to the skeleton, endocrine system, reproductive orga...
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| Format: | Article |
| Language: | English |
| Published: |
The Company of Biologists
2016-10-01
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| Series: | Disease Models & Mechanisms |
| Subjects: | |
| Online Access: | http://dmm.biologists.org/content/9/10/1169 |
| _version_ | 1818527404664029184 |
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| author | Laura J. Lambert Anil K. Challa Aidi Niu Lihua Zhou Janusz Tucholski Maria S. Johnson Tim R. Nagy Alan W. Eberhardt Patrick N. Estep Robert A. Kesterson Jayleen M. Grams |
| author_facet | Laura J. Lambert Anil K. Challa Aidi Niu Lihua Zhou Janusz Tucholski Maria S. Johnson Tim R. Nagy Alan W. Eberhardt Patrick N. Estep Robert A. Kesterson Jayleen M. Grams |
| author_sort | Laura J. Lambert |
| collection | DOAJ |
| description | Osteocalcin, also known as bone γ-carboxyglutamate protein (Bglap), is expressed by osteoblasts and is commonly used as a clinical marker of bone turnover. A mouse model of osteocalcin deficiency has implicated osteocalcin as a mediator of changes to the skeleton, endocrine system, reproductive organs and central nervous system. However, differences between mouse and human osteocalcin at both the genome and protein levels have challenged the validity of extrapolating findings from the osteocalcin-deficient mouse model to human disease. The rat osteocalcin (Bglap) gene locus shares greater synteny with that of humans. To further examine the role of osteocalcin in disease, we created a rat model with complete loss of osteocalcin using the CRISPR/Cas9 system. Rat osteocalcin was modified by injection of CRISPR/Cas9 mRNA into the pronuclei of fertilized single cell Sprague-Dawley embryos, and animals were bred to homozygosity and compound heterozygosity for the mutant alleles. Dual-energy X-ray absorptiometry (DXA), glucose tolerance testing (GTT), insulin tolerance testing (ITT), microcomputed tomography (µCT), and a three-point break biomechanical assay were performed on the excised femurs at 5 months of age. Complete loss of osteocalcin resulted in bones with significantly increased trabecular thickness, density and volume. Cortical bone volume and density were not increased in null animals. The bones had improved functional quality as evidenced by an increase in failure load during the biomechanical stress assay. Differences in glucose homeostasis were observed between groups, but there were no differences in body weight or composition. This rat model of complete loss of osteocalcin provides a platform for further understanding the role of osteocalcin in disease, and it is a novel model of increased bone formation with potential utility in osteoporosis and osteoarthritis research. |
| first_indexed | 2024-12-11T06:35:44Z |
| format | Article |
| id | doaj.art-4416ba08da51475b9e8b9c3f546ec6a0 |
| institution | Directory Open Access Journal |
| issn | 1754-8403 1754-8411 |
| language | English |
| last_indexed | 2024-12-11T06:35:44Z |
| publishDate | 2016-10-01 |
| publisher | The Company of Biologists |
| record_format | Article |
| series | Disease Models & Mechanisms |
| spelling | doaj.art-4416ba08da51475b9e8b9c3f546ec6a02022-12-22T01:17:22ZengThe Company of BiologistsDisease Models & Mechanisms1754-84031754-84112016-10-019101169117910.1242/dmm.025247025247Increased trabecular bone and improved biomechanics in an osteocalcin-null rat model created by CRISPR/Cas9 technologyLaura J. Lambert0Anil K. Challa1Aidi Niu2Lihua Zhou3Janusz Tucholski4Maria S. Johnson5Tim R. Nagy6Alan W. Eberhardt7Patrick N. Estep8Robert A. Kesterson9Jayleen M. Grams10 Department of Genetics, University of Alabama at Birmingham, Birmingham, AL 35294, USA Department of Genetics, University of Alabama at Birmingham, Birmingham, AL 35294, USA Department of Surgery, University of Alabama at Birmingham, Birmingham, AL 35294, USA Department of Surgery, University of Alabama at Birmingham, Birmingham, AL 35294, USA Department of Surgery, University of Alabama at Birmingham, Birmingham, AL 35294, USA Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, AL 35294, USA Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, AL 35294, USA Department of Biomedical Engineering, University of Alabama at Birmingham, Birmingham, AL 35294, USA Department of Biomedical Engineering, University of Alabama at Birmingham, Birmingham, AL 35294, USA Department of Genetics, University of Alabama at Birmingham, Birmingham, AL 35294, USA Department of Surgery, University of Alabama at Birmingham, Birmingham, AL 35294, USA Osteocalcin, also known as bone γ-carboxyglutamate protein (Bglap), is expressed by osteoblasts and is commonly used as a clinical marker of bone turnover. A mouse model of osteocalcin deficiency has implicated osteocalcin as a mediator of changes to the skeleton, endocrine system, reproductive organs and central nervous system. However, differences between mouse and human osteocalcin at both the genome and protein levels have challenged the validity of extrapolating findings from the osteocalcin-deficient mouse model to human disease. The rat osteocalcin (Bglap) gene locus shares greater synteny with that of humans. To further examine the role of osteocalcin in disease, we created a rat model with complete loss of osteocalcin using the CRISPR/Cas9 system. Rat osteocalcin was modified by injection of CRISPR/Cas9 mRNA into the pronuclei of fertilized single cell Sprague-Dawley embryos, and animals were bred to homozygosity and compound heterozygosity for the mutant alleles. Dual-energy X-ray absorptiometry (DXA), glucose tolerance testing (GTT), insulin tolerance testing (ITT), microcomputed tomography (µCT), and a three-point break biomechanical assay were performed on the excised femurs at 5 months of age. Complete loss of osteocalcin resulted in bones with significantly increased trabecular thickness, density and volume. Cortical bone volume and density were not increased in null animals. The bones had improved functional quality as evidenced by an increase in failure load during the biomechanical stress assay. Differences in glucose homeostasis were observed between groups, but there were no differences in body weight or composition. This rat model of complete loss of osteocalcin provides a platform for further understanding the role of osteocalcin in disease, and it is a novel model of increased bone formation with potential utility in osteoporosis and osteoarthritis research.http://dmm.biologists.org/content/9/10/1169OsteocalcinBone strengthBone structureGenetic animal modelsOsteocalcin knockout |
| spellingShingle | Laura J. Lambert Anil K. Challa Aidi Niu Lihua Zhou Janusz Tucholski Maria S. Johnson Tim R. Nagy Alan W. Eberhardt Patrick N. Estep Robert A. Kesterson Jayleen M. Grams Increased trabecular bone and improved biomechanics in an osteocalcin-null rat model created by CRISPR/Cas9 technology Disease Models & Mechanisms Osteocalcin Bone strength Bone structure Genetic animal models Osteocalcin knockout |
| title | Increased trabecular bone and improved biomechanics in an osteocalcin-null rat model created by CRISPR/Cas9 technology |
| title_full | Increased trabecular bone and improved biomechanics in an osteocalcin-null rat model created by CRISPR/Cas9 technology |
| title_fullStr | Increased trabecular bone and improved biomechanics in an osteocalcin-null rat model created by CRISPR/Cas9 technology |
| title_full_unstemmed | Increased trabecular bone and improved biomechanics in an osteocalcin-null rat model created by CRISPR/Cas9 technology |
| title_short | Increased trabecular bone and improved biomechanics in an osteocalcin-null rat model created by CRISPR/Cas9 technology |
| title_sort | increased trabecular bone and improved biomechanics in an osteocalcin null rat model created by crispr cas9 technology |
| topic | Osteocalcin Bone strength Bone structure Genetic animal models Osteocalcin knockout |
| url | http://dmm.biologists.org/content/9/10/1169 |
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