Effect Of Xiangpi Shengji Ointment On The Expression Of MMP-1, MMP-2, MMP-9, MMP-13, TIMP-1 And TIMP-2 In Wound Tissue Of Rat Chronic Wound Mode

Objective: This study is based on establishing a rat chronic wound model and intervening with Xiangpi Shengji ointment,so as to dynamically observe the changes of the contents of MMP-1,MMP-2,MMP-9,MMP-13,TIMP-1 and TIMP-2 in the wound tissue at four different time points.The purpose of this study is to explore the microscopic mechanism of the test product in the treatment of chronic wounds,so as to provide a solid experimental theoretical basis for the application of Xiangpi Shengji Ointment in the clinical treatment of chronic wounds.Methods:Based on the full-thickness skin defect method of Academician Fu Xiaobing et al,SD male rats were fed in the experimental center for 7 days to establish a chronic wound model.According to the body weight of the experimental mice,they were divided into 4 groups by random number table method,namely blank group,model group,experimental group and control group,with 24 mice in each group.After grouping,recombinant bovine basic fibroblast growth factor gel and Xiangpi Shengji ointment were used to intervene the treatment of the control group and the experimental group,while the other two groups were treated with normal saline.Results:After the experiment,none of the experimental mice in each group died,among which their vital signs were stable,and activity status,food intake and water intake were normal,and the wound application position was good.Wound Healing Rate: The wound healing rates of the control group and the experimental group at 4 time points were higher than those of the model group(P<0.05).There was no significant difference in the wound healing rate between the experimental group and the control group on the 3rd and14 th days of treatment(P>0.05).The wound healing rate of the control group on the 7th and 21 st days of treatment was slightly lower than that of the experimental group(P<0.05).Pathological Detection: Through observation,the skin of the experimental mice in the blank group was normal,with normal skin appendages,regular collagen fibers and a small amount of fibroblasts.On the 3rd day,tissue necrosis area,a large number of inflammatory cell infiltration,obvious edema and disordered and sparse capillary distribution were observed in each group under the microscope.On the 7th day,the inflammatory cell infiltration,edema and capillary distribution of the experimental mice in each group were improved to varying degrees,and the improvement in the experimental group and the control group was more significant than that in the model group.On the14 th day,the conditions of the experimental mice in each group were further improved,and the improvement of the experimental group and the control group was still significantly better than that of the model group.By observation,on the 21 st day,except for the model group,there were almost no inflammatory cells in the other two groups of experimental mice,and at the same time,neatly arranged collagen fibers and normal skin appendages were seen growing,and capillaries were abundant.Collagen fibers with disordered sequence can be seen in the model group.Analysis of the differences in the expression of cytokines in the wounds between the groups: the blank group was not given special treatment,and there was no significant difference in the expression levels of each cytokine before and after(P>0.05),and the expression levels of each cytokine were lower at four time points than the other three groups(P<0.05).Analysis of the differences in the expression of cytokines in the wounds between the groups: the blank group was not given special treatment,and there was no significant difference in the expression levels of each cytokine before and after(P>0.05),and the expression levels of each cytokine were lower at four time points than the other three groups(P<0.05).On the 7th day after treatment: the expressions of MMP-1,MMP-2,MMP-9,MMP-13,TIMP-1 and TIMP-2 in the wound tissues of the experimental group and the control group were higher than those of the model group(P< 0.05),the experimental group was higher than the control group(P<0.05).On the 14 th day after treatment: the expressions of MMP-1,MMP-2 and MMP-9in the wound tissues of the experimental group and the control group were lower than those of the model group(P<0.05),and the expressions of TIMP-1 and TIMP-2 all were higher than the model group(P<0.05).On the 21 st day after treatment: the expressions of MMP-1,MMP-2,MMP-9,MMP-13 and TIMP-1 in the wound tissues of the experimental group and the control group were lower than those of the model group(P<0.05).The expression of TIMP-2 in the experimental group was lower than that in the control group(P<0.05).Trend analysis of cytokines in wound tissue of each group: The expressions of MMP-1,MMP-2,MMP-9,MMP-13,TIMP-1 and TIMP-2 in the model group entirely showed a continuous increasing trend.Besides,the control group was similar to the experimental group,the expressions of MMP-1,MMP-2,MMP-9,MMP-13,TIMP-1 and TIMP-2 all showed a trend of first increasing and then decreasing,but the peak of TIMP-1and TIMP-2 appeared later than that of MMP-1,MMP-2,MMP-9,MMP-13.Conclusions:(1)Xiangpi Shengji Ointment can significantly improve the healing rate of chronic wounds,significantly shorten the healing time of wounds,effectively promote the improvement of wound tissues,and accelerate the repair of chronic wounds.(2)Xiangpi Shengji Ointment can effectively increase the expression levels of MMP-1,MMP-2,MMP-9 and MMP-13 in the granulation tissue of chronic wounds in the early stage,and effectively regulate the expression levels of TIMP-1 and TIMP-2 in the granulation tissue of early chronic wounds.Besides,it can inhibit the relative activities of MMP-1,MMP-2,MMP-9,and MMP-13,thereby regulating the homeostasis of ECM and accelerating the healing of chronic wounds.(3)Xiangpi Shengji Ointment can affect the expression of matrix protease and matrix protease inhibitors,which may be able to maintain the dynamic balance between the two types of factors.