Biomedical Research Centre, Vancouver, Canada.
J Orthop Res. 2011 Feb;29(2):289-96. doi: 10.1002/jor.21220. Epub 2010 Aug 25.
This study investigated the expression of Scleraxis in a murine model of patellar tendon injury in which the central third of the patellar tendon was unilaterally injured. The presence of tendon pathology was assessed using dual photon microscopy, conventional histology and microCT. Tendon pathology was also quantified noninvasively over a 12-week period using high-frequency ultrasound and laser Doppler flowmetry. Gene expression (Scx, Tnmd, and Col1a1) was determined at defined end-points (1, 4, 8, and 12 weeks) using qPCR on RNA from individual patellar tendons on injured and uninjured sides. There was significant development of tendon pathology as gauged by ultrasound and laser Doppler over 12 weeks. Injured tendons demonstrated significant histological and microCT evidence of pathological change, and disorganized collagen with reduced density. The expression of Scx and Col1a1 was unchanged at 1 week, significantly upregulated at 4 and 8 weeks, and had returned to baseline by 12 weeks. Tnmd expression was unchanged at 1 week, and significantly increased at 4, 8, and 12 weeks. Patellar tendon injury was associated with marked increases in the expression of Scx, Tnmd, and Col1a1. Our data suggest new roles for Scleraxis in coordinating the response to injury in the pathogenesis of tendon disorders.
本研究通过单侧髌腱中央三分之一损伤的小鼠模型，调查了 Scleraxis 在其中的表达情况。采用双光子显微镜、常规组织学和 microCT 评估腱病的存在。在 12 周的时间内，还通过高频超声和激光多普勒血流仪对腱病进行了非侵入性定量评估。通过对损伤侧和未损伤侧的单个髌腱的 RNA 进行 qPCR，在特定时间点（1、4、8 和 12 周）确定基因表达（Scx、Tnmd 和 Col1a1）。在 12 周的时间内，通过超声和激光多普勒检测到腱病明显发展。损伤的腱显示出明显的组织学和 microCT 病理性改变，胶原排列紊乱，密度降低。Scx 和 Col1a1 的表达在 1 周时没有变化，在 4 周和 8 周时显著上调，并在 12 周时恢复到基线水平。Tnmd 的表达在 1 周时没有变化，在 4、8 和 12 周时显著增加。髌腱损伤与 Scx、Tnmd 和 Col1a1 表达的显著增加有关。我们的数据表明，Scleraxis 在协调对肌腱疾病发病机制中损伤反应方面具有新的作用。
