A Continuous Observation of the Degenerative Process in the Intervertebral Disc of Smad3 Gene Knock-Out Mice
A Continuous Observation of the Degenerative Process in the Intervertebral Disc of Smad3 Gene Knock-Out Mice
复制标题
Smad3基因敲除小鼠椎间盘退变过程的连续观察
DOI：
10.1097/brs.0b013e3181a3c7c7
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发表时间：
2009-06-01
期刊：
影响因子：
3
通讯作者：
Wang, Yong-Jun
中科院分区：
文献类型：
--
作者：
Li, Chen-Guang;Liang, Qian-Qian;Wang, Yong-Jun
研究设计.观察不同时间点小母鼠对断头脑瘫（Smad）3（-/-）小鼠脊柱的病理变化。目的观察Smad 3基因敲除小鼠生长过程中椎间盘的退变情况。Smad 3基因敲除（Smad 3（-/-））小鼠表现出与人类骨关节炎相似的表型。尽管IVD软骨终板和关节软骨之间存在相似性，但对探索IVD退变可能由Smad 3缺陷驱动的可能性的兴趣相对较少。分别于生后10、30、60 d处死Smad 3（-/-）小鼠，取脊髓IVD标本进行组织学和免疫组化研究。从这些样本中分离的总RNA用于实时PCR分析II型胶原（Col 2 α 1）、X型胶原（Col 10 α 1）、聚集蛋白聚糖和转化生长因子-β 1（TGF-β 1）。与野生型小鼠相比，Smad 3（-/-）小鼠的体型明显较小。X线片显示Smad 3（-/-）小鼠脊柱畸形、后凸。组织学检查显示，Smad 3（-/-）小鼠椎间盘软骨终板高度降低，蛋白多糖和胶原含量减少。随着生长，尤其是30和60天龄的Smad 3（-/-）小鼠，椎间盘中II型胶原、聚集蛋白聚糖和TGF-β 1的蛋白阳性染色减少，而X型胶原的蛋白阳性染色增加。实时荧光定量PCR检测结果显示，Col 2 α 1、聚集蛋白聚糖和TGF-β 1的mRNA表达水平下降，而Col 10 α 1的mRNA表达水平升高。Smad 3基因敲除小鼠随着生长发生IVD变性。
Study Design. Pathologic changes were observed in the spine of small mother against decapentaplegic (Smad) 3(-/-) mice at different time points.Objective. To observe the degeneration of the intervertebral disc (IVD) in Smad3 gene knock-out mice with growth.Summary of Background Data. Smad3 gene knock-out (Smad3(-/-)) mice displays phenotypes similar to human osteoarthritis. Despite the similarities between IVD cartilage endplate and the articular cartilage, there has been relatively little interest in exploring the possibility that IVD degeneration might be driven by the deficiency of Smad3.Methods. The Smad3(-/-) mice were killed at the 10th, 30th, and 60th day after their birth and the IVD samples of spine were harvested for histologic and immunohistochemical studies. Total RNA isolated from these samples were used for real-time PCR analysis of type II collagen (Col2 alpha 1), type X collagen (Col10 alpha 1), aggrecan, and transforming growth factor-beta 1 (TGF-beta 1).Results. Compared with the wild-type mice, Smad3(-/-) mice appeared significantly smaller in size. Radiograph showed that the spine of Smad3(-/-) mice is malformation and kyphosis. Histologic analysis revealed the declined height of cartilage endplate, decreased proteoglycan and collagen content in disc of Smad3(-/-) mice. With growth, especially of the 30- and 60-day old Smad3(-/-) mice, the protein positive staining of type II collagen, aggrecan, and TGF-beta 1 in the disc decreased, while that of type X collagen increased. And the analysis of real-time PCR showed that the mRNA expression of Col2 alpha 1, aggrecan, and TGF-beta 1 decreased, while that of Col10 alpha 1 increased.Conclusion. Smad3 gene knock-out mice develop IVD degeneration with growth.