Miragliotta Vincenzo, Raphaël Kevin, Ipiña Zoë, Lussier Jacques G, Theoret Christine L
Department of Veterinary Anatomy, Biochemistry and Physiology, University of Pisa, Pisa, Italy.
Physiol Genomics. 2009 Jul 9;38(2):149-57. doi: 10.1152/physiolgenomics.90383.2008. Epub 2009 Apr 28.
Wound healing in horses is complicated, particularly when wounds are on the limb. The objectives of this study were to clone equine thrombospondin II (THBS2) and secreted protein acidic and cysteine-rich (SPARC) cDNAs and to compare the spatiotemporal expression of mRNAs and proteins during repair of body and limb wounds. These molecules were targeted in view of their potential biological contribution to angiogenesis, which is exacerbated during the repair of limb wounds in horses. Cloning was achieved by screening size-selected cDNA libraries previously derived from 7-day-old wounds. Expression was studied in unwounded skin and in samples from 1, 2, 3, 4, and 6 wk old wounds of the body and limb. Temporal gene expression was determined by semiquantitative RT-PCR, while protein expression was mapped immunohistochemically. The temporal pattern of expression for both genes was similar; wounding caused immediate upregulation of mRNA, which did not return to baseline by the end of the study, and overexpression was noted in body relative to limb wounds. Immunostaining for THBS2 and SPARC was induced by wounding, though no differences in stain location or intensity were detected between body and limb wounds. This study is the first to characterize equine cDNA for THBS2 and SPARC and to document mRNA expression over the different phases of repair. THBS2 and SPARC might modulate angiogenesis during wound healing in the horse, which could protect against the disproportionate fibroplasia commonly afflicting limb wounds and leading to the development of exuberant granulation tissue.
马匹的伤口愈合很复杂，尤其是当伤口位于肢体上时。本研究的目的是克隆马血小板反应蛋白II（THBS2）和富含酸性和半胱氨酸的分泌蛋白（SPARC）的cDNA，并比较身体和肢体伤口修复过程中mRNA和蛋白质的时空表达。鉴于这些分子对血管生成可能具有的生物学作用，而在马的肢体伤口修复过程中血管生成会加剧，因此将它们作为研究对象。通过筛选先前从7日龄伤口获得的大小选择cDNA文库来实现克隆。在未受伤的皮肤以及身体和肢体1、2、3、4和6周龄伤口的样本中研究表达情况。通过半定量RT-PCR确定基因的时间表达，而通过免疫组织化学绘制蛋白质表达图谱。两个基因的时间表达模式相似；受伤导致mRNA立即上调，在研究结束时未恢复到基线水平，并且相对于肢体伤口，身体伤口中观察到过表达。THBS2和SPARC的免疫染色是由伤口诱导的，尽管在身体和肢体伤口之间未检测到染色位置或强度的差异。本研究首次对马的THBS2和SPARC的cDNA进行了表征，并记录了修复不同阶段的mRNA表达。THBS2和SPARC可能在马的伤口愈合过程中调节血管生成，这可以防止肢体伤口常见的过度纤维化，并导致过度增生性肉芽组织的形成。
