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Published on: January 25, 2018
Expressions of TGF-β1 and EⅢA-FN after Rat Skeletal Muscle Contusion and Wound Age Estimation
R Liu1,2, L Z Ge3, H D Zhang1,2
1Collaborative Innovation Center of Judicial Civilization, Beijing 100088, China.
Abstract:
Objective To study the expressions of transforming growth factor-β1 (TGF-β1) and EⅢA-fibronectin (EⅢA-FN) at different time points of antemortem injury, antemortem injury postmortem expression and postmortem injury and to explore their application value in wound age estimation. Methods A model of rat skeletal muscle contusion was established. The rats were randomly divided into normal control group (n=5), antemortem contusion group (n=40), antemortem contusion postmortem expression group (n=110) and postmortem injury group (n=25). The expressions of TGF-β1 and EⅢA-FN after rat skeletal muscles antemortem contusion were detected with immunohistochemical staining. Expression changes of TGF-β1 and EⅢA-FN mRNA in each group were analyzed with real-time fluorescence quantitative PCR. Results Immunohistochemical staining results showed that a large number of polymorphonuclear leukocyte, mononuclear cells and fibroblastic cells showed a strong expression of TGF-β1 in wounded zones 12 h-14 d after antemortem contusion. EⅢA-FN was mainly distributed in the extracellular matrix, 3 to 7 d post-traumatic. Real-time fluorescence quantitative PCR results showed that TGF-β1 and EⅢA-FN mRNA in antemortem injury group reached the peak at 3 and 5 d post-traumatic respectively. The expressions of TGF-β1 and EⅢA-FN mRNA in antemortem contusion postmortem expression group peaked at 6 h and 12 h postmortem. The expression of TGF-β1 and EⅢA-FN mRNA in postmortem injury group 0.5-12 h postmortem was significantly lower than those of the normal control group and the antemortem contusion group. Conclusion TGF-β1 and EⅢA-FN might become a reference index for skeletal muscle wound age estimation.
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