Cartilage-specific over-expression of CCN family member 2/connective tissue growth factor (CCN2/CTGF) stimulates insulin-like growth factor expression and bone growth.
Cartilage-specific over-expression of CCN family member 2/connective tissue growth factor (CCN2/CTGF) stimulates insulin-like growth factor expression and bone growth.
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DOI：
10.1371/journal.pone.0059226
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发表时间：
2013
期刊：
影响因子：
3.7
通讯作者：
Takigawa M
中科院分区：
文献类型：
--
作者：
Tomita N;Hattori T;Itoh S;Aoyama E;Yao M;Yamashiro T;Takigawa M
先前我们表明CCN家族成员2/结缔组织生长因子（CCN 2）促进体外生长软骨细胞的增殖、分化和成熟。为了阐明CCN 2在体内软骨发育中的特定作用和分子机制，在本研究中，我们产生了过表达CCN 2的转基因小鼠，并分析了它们在软骨和骨发育方面的作用。产生在软骨中在6 kb-Col 2a 1-增强子/启动子的控制下表达ccn 2/lacZ融合基因的转基因小鼠。软骨和骨发育的变化进行了组织学和免疫组织学分析，并通过显微CT。培养原代软骨细胞以及肢芽间充质细胞并分析软骨相关基因表达的变化，并在培养物中用重组CCN 2处理非转基因软骨细胞。新生的转基因小鼠显示其长骨延长，蛋白多糖含量增加和II型胶原积累。转基因骨骼的显微CT分析表明骨厚度和矿物质密度增加。软骨细胞增殖在转基因软骨中增强。在体外短期培养的转基因软骨细胞中，col 2a 1、聚集蛋白聚糖和ccn 2基因的表达显著增强;在长期培养中，这些基因的表达水平进一步增强。此外，在体外软骨形成强烈增强。IGF-I和IGF-II mRNA水平在转基因软骨细胞中升高，用重组CCN 2处理非转基因软骨细胞刺激这些mRNA的表达。向非转基因软骨细胞中加入CCN 2诱导IGFR的磷酸化，并且CCN 2过表达的软骨细胞显示IGFR的磷酸化增强。我们的数据表明，观察到的CCN 2的影响可能部分介导的CCN 2诱导的IGF-I和IGF-II的过表达。这些发现表明，CCN 2在转基因小鼠中的过表达加速了软骨内骨化过程，导致其长骨长度增加。我们的研究结果还表明，局部增强的IGF-I或IGF-II可能参与这种延长的骨生长。
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.
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影响因子：
4.8
作者：
Chen, CC;Chen, NY;Lau, LF
通讯作者：
Lau, LF
影响因子：
5.3
作者：
Lefebvre, V;Huang, WD;deCrombrugghe, B
通讯作者：
deCrombrugghe, B
影响因子：
10.5
作者：
Murakami, S;Balmes, G;de Crombrugghe, B
通讯作者：
de Crombrugghe, B
影响因子：
4.8
作者：
Hattori, Takako;Eberspaecher, Heidi;de Crombrugghe, Benoit
通讯作者：
de Crombrugghe, Benoit
影响因子：
--
作者：
HOLMDAHL, R;RUBIN, K;WIGZELL, H
通讯作者：
WIGZELL, H