Tian Zhi-Ling, Jiang Shu-Kun, Zhang Miao, Wang Meng, Li Jiao-Yong, Zhao Rui, Wang Lin-Lin, Li Shan-Shan, Liu Min, Zhang Meng-Zhou, Guan Da-Wei
Department of Forensic Pathology, China Medical University School of Forensic Medicine, No.77, Puhe Road, Shenbei New Area, Shenyang, 110122, Liaoning Province, People's Republic of China.
Int J Legal Med. 2016 Jan;130(1):163-72. doi: 10.1007/s00414-015-1251-x. Epub 2015 Aug 27.
The study was focused on time-dependent expressions of paired-box transcription factor 7 (Pax7) and myoblast determination protein (MyoD) during skeletal muscle wound healing. An animal model of skeletal muscle contusion was established in 40 Sprague-Dawley male rats. Samples were taken at 1, 3, 5, 7, 9, 13, 17, and 21 days after injury, respectively (five rats in each posttraumatic interval). Five rats were employed as control. By morphometric analysis, the data based on the number of Pax7(+)/MyoD(-), Pax7(+)/MyoD(+), and Pax7(-)/MyoD(+) cells were highly correlated with the wound age. Pax7 and MyoD expressions were upregulated after injury by Western blot and quantitative real-time PCR assays. The relative quantity of Pax7 protein peaked at 5 days after injury, which was >1.13, and decreased thereafter. Similarly, the relative quantity of MyoD mRNA expression peaked at 3 days after injury, which was >2.59. The relative quantity of Pax7 protein >0.73 or mRNA expression >2.38 or the relative quantity of MyoD protein >1.33 suggested a wound age of 3 to 7 days. The relative quantity of MyoD mRNA expression >2.02 suggested a wound age of 1 to 7 days post-injury. In conclusion, the expressions of Pax7 and MyoD are upregulated in a time-dependent manner during skeletal muscle wound healing, suggesting that Pax7 and MyoD may be potential markers for wound age estimation in skeletal muscle.
该研究聚焦于骨骼肌创伤愈合过程中成对盒转录因子7（Pax7）和成肌细胞决定蛋白（MyoD）的时间依赖性表达。在40只雄性Sprague-Dawley大鼠中建立骨骼肌挫伤动物模型。分别在损伤后1、3、5、7、9、13、17和21天取样（每个创伤后时间段5只大鼠）。5只大鼠作为对照。通过形态计量分析，基于Pax7(+)/MyoD(-)、Pax7(+)/MyoD(+)和Pax7(-)/MyoD(+)细胞数量的数据与伤口年龄高度相关。通过蛋白质印迹法和定量实时PCR检测发现，损伤后Pax7和MyoD表达上调。Pax7蛋白的相对量在损伤后5天达到峰值，>1.13，此后下降。同样，MyoD mRNA表达的相对量在损伤后3天达到峰值，>2.59。Pax7蛋白相对量>0.73或mRNA表达>2.38或MyoD蛋白相对量>1.33表明伤口年龄为3至7天。MyoD mRNA表达相对量>2.02表明损伤后1至7天的伤口年龄。总之，在骨骼肌创伤愈合过程中，Pax7和MyoD的表达呈时间依赖性上调，提示Pax7和MyoD可能是估计骨骼肌伤口年龄的潜在标志物。
