ABSTRACT
Objective To observe the performances of autophagy and inlfammatory cytokines in wounded mice skin at different time, and to explore the relationship between these performances and the duration of wound in the mice. Methods RT-PCR and West-blot methods were used to detect the genetic expression and protein expression of Beclin-1, LC-3, IL-1α, IL-1β, and MCP-1 in wounded skin of the mice. Results After the mice’s skin was wounded, the level of IL-1a and IL-1β genetic and protein expression increased early, the peak was found after 12 hours, and then decreased; the expression of MCP-1 began to increase after 6 hours and it reached peak after 48 hours, then decreased; while the genetic and protein expression of LC3 and beclin-1 began to increase after 6 hours, and the peak was seen after 24hours, then decreased too. Conclusion After the mice’s skin was wounded, the starting and the peak of the expression of autophagy came later than those of inlfammatory cytokines, it is found the level of the expression of inlfammatory cytokines was showing a downward trend when the expression of autophagy reached the peak. This performance may be caused by increasing inlfammatory cytokines in the tissue of the incised wound, which activated the autophagy, and when the level of autophagy reached a certain degree, it could suppress the excessive inlfammatory reaction. So the autophagy and the inlfammatory cytokines interact regularly after the mice’s skin was wounded, and such interaction offers us a reference to infer the injury time after injury.
ABSTRACT
Objective:To explore the expression of MMP-2 and MMP-9 in rat skin after injury and its relationship with the wound time,in order to supply an experimental evidence for the prediction of injury time.Methods:After a model of incision of rat's skin was set,immuno-histochemistry technique and auto-image analysis were used to study the expression of MMP-2 and MMP-9 at different post-traumatic time intervals in both antemortem and post-mortem groups.Results:The expression of MMP-2 and MMP-9 in ante mortem group was higher than that in the normal control group(P0.05).Further,the expression of MMP-2 could be detected as increasing at 0.5 h,and reached maximum on 3 d,maintained the high level to the 5th day,then decreased gradually ,returned to norma1 lastly on 12～14 d.Compared with MMP-2,the expression of MMP-9 could be detected increasing at l h,and reached maximum on 3 d,maintained the high level to the 5th day,then decreased gradually,returned to norma1 lastly on 12～14 d .From 0.5 h to 3 d of wound interva1,the expression of MMP isoforms were identified in a large number of infiltrating neutrophilic granulocytes ,afterwards the fibroblastic cells(FBCs) and the vascular endothelial cells accounted for the most part of the MMP-2and MMP-9 positive cells.Conclusion:The expression of MMP-2 and MMP-9 in rat's skin is time dependent after skin injury,which could be used as a bio-marker to determine the time of injury.