PloS one, 2013-03, Vol.8 (3), p.e59226-e59226
2013
Volltextzugriff (PDF)
Details
- Autor(en) / Beteiligte
- Titel
- Cartilage-specific over-expression of CCN family member 2/connective tissue growth factor (CCN2/CTGF) stimulates insulin-like growth factor expression and bone growth
- Ist Teil von
- PloS one, 2013-03, Vol.8 (3), p.e59226-e59226
- Ort / Verlag
- United States: Public Library of Science
- Erscheinungsjahr
- 2013
- Quelle
- MEDLINE
- Beschreibungen/Notizen
- Previously we showed that CCN family member 2/connective tissue growth factor (CCN2) promotes the proliferation, differentiation, and maturation of growth cartilage cells in vitro. To elucidate the specific role and molecular mechanism of CCN2 in cartilage development in vivo, in the present study we generated transgenic mice overexpressing CCN2 and analyzed them with respect to cartilage and bone development. Transgenic mice were generated expressing a ccn2/lacZ fusion gene in cartilage under the control of the 6 kb-Col2a1-enhancer/promoter. Changes in cartilage and bone development were analyzed histologically and immunohistologically and also by micro CT. Primary chondrocytes as well as limb bud mesenchymal cells were cultured and analyzed for changes in expression of cartilage-related genes, and non-transgenic chondrocytes were treated in culture with recombinant CCN2. Newborn transgenic mice showed extended length of their long bones, increased content of proteoglycans and collagen II accumulation. Micro-CT analysis of transgenic bones indicated increases in bone thickness and mineral density. Chondrocyte proliferation was enhanced in the transgenic cartilage. In in vitro short-term cultures of transgenic chondrocytes, the expression of col2a1, aggrecan and ccn2 genes was substantially enhanced; and in long-term cultures the expression levels of these genes were further enhanced. Also, in vitro chondrogenesis was strongly enhanced. IGF-I and IGF-II mRNA levels were elevated in transgenic chondrocytes, and treatment of non-transgenic chondrocytes with recombinant CCN2 stimulated the expression of these mRNA. The addition of CCN2 to non-transgenic chondrocytes induced the phosphorylation of IGFR, and ccn2-overexpressing chondrocytes showed enhanced phosphorylation of IGFR. Our data indicates that the observed effects of CCN2 may be mediated in part by CCN2-induced overexpression of IGF-I and IGF-II. These findings indicate that CCN2-overexpression in transgenic mice accelerated the endochondral ossification processes, resulting in increased length of their long bones. Our results also indicate the possible involvement of locally enhanced IGF-I or IGF-II in this extended bone growth.
- Sprache
- Englisch
- Identifikatoren
- ISSN: 1932-6203eISSN: 1932-6203DOI: 10.1371/journal.pone.0059226Titel-ID: cdi_plos_journals_1330900319
- Format
- –
- Schlagworte
- Aggrecan, Angiogenesis, Animals, Animals, Newborn, Biochemistry, Biology, Biomarkers - metabolism, Bone (endochondral), Bone and Bones - cytology, Bone and Bones - metabolism, Bone density, Bone growth, Bone mineral density, Bones, Cartilage, Cartilage - cytology, Cartilage - growth & development, Cartilage - metabolism, Cell culture, Cell Proliferation, Chemistry, Chondrocytes, Chondrocytes - cytology, Chondrocytes - metabolism, Chondrogenesis, Collagen (type II), Computed tomography, Connective tissue growth factor, Connective Tissue Growth Factor - genetics, Connective Tissue Growth Factor - metabolism, Connective tissues, Dental schools, Dentistry, Endochondral bone, Endocrinology, Extracellular matrix, Fibroblasts, Fusion protein, Gene Expression, Genes, Heparan sulfate, In vivo methods and tests, Insulin, Insulin-like growth factor I, Insulin-Like Growth Factor I - genetics, Insulin-Like Growth Factor I - metabolism, Insulin-like growth factor II, Insulin-Like Growth Factor II - genetics, Insulin-Like Growth Factor II - metabolism, Insulin-like growth factors, Limb buds, Limb Buds - cytology, Limb Buds - growth & development, Limb Buds - metabolism, Medicine, Mesenchymal Stem Cells - cytology, Mesenchymal Stem Cells - metabolism, Mesenchyme, Mice, Mice, Transgenic, mRNA, Orthodontics, Ossification, Overexpression, Pharmaceutical sciences, Phosphorylation, Promoter Regions, Genetic, Proteins, Proteoglycans, Receptors, Somatomedin - genetics, Receptors, Somatomedin - metabolism, Rodents, Transgenic animals, Transgenic mice, University graduates