Effects Of MEBT/MEBO On The Expression Of AKT/EGF Signaling System In Chronic Wounds

Objective: To further investigate the mechanism of MEBT/MEBO promoting the repair of chronic refractory wounds from the AKT/EGF signaling pathway.Methods: 60 adult SPF Wistar male rats,12 weeks old,weighing 220g~250g,after 1 weeks of feeding,were randomly divided into blank group 12,control group(acute full-thickness group)12 rats,model group 12,MEBO group 12,bFGF group 12.The rats in the blank group without any injury treatment;control group rats in the modeling of parts for full-thickness skin excision,but without the injection of hydrocortisone;After full-thickness skin excision in the molding parts,the rats in the chronic wounds group are injected the hydrocortisone to make chronic wounds models,then according to the treatment method were randomly divided into model group,MEBO group and bFGF group,12 rats in each group.Wounds in each group were treated immediately after making.On the third days,seventh day and fourteenth day after modeling,4 rats were killed in each group,take fresh wound tissue,immediately placed in liquid nitrogen tanks,and then quickly transferred to the-80℃ after the material is finished.After all ecimens are collected,using Western Blotting,RT-PCR method to detect the protein and gene expression of AKT,EGF and MMP-2.Results:(1)General wound situation and wound healing time: blank group wound recovered best,MEBO group and bFGF group was significantly better than the model group(2)Western Bloting:(1)The MMP-2 expression in granulation tissue of rats wound in MEBO group,bFGF group and control group changed with time are showing a increasing-decreasing trend(P<0.05);Chronic wound group showed a increasing trend(P<0.05);In the blank group,the rats tissue was normal skin,the expression of MMP-2 was not significantly changed due to the absence of injury treatment(P>0.05).(2)The EGFR expression in granulation tissue of rats wound in MEBO group,bFGF group and control group changed with time are showing a increasing-decreasing trend(P<0.05);Chronic wound group showed a increasing trend(P<0.05);The EGFR expression of three time points in MEBO group,bFGF group,control group and chronic wound group have significant differences(P<0.05);In the blank group,the rats tissue was normal skin,the expression of EGFR was not significantly changed due to the absence of injury treatment(P>0.05).(3)The p-AKT expression in granulation tissue of rats wound in MEBO group,bFGF group and control group changed with time are showing a increasing-decreasing trend(P<0.05);Chronic wound group showed a increasing trend(P<0.05);The p-AKT expression of three time points in MEBO group have significant differences(P<0.05);In the blank group,the rats tissue was normal skin,the expression of p-AKT was not significantly changed due to the absence of injury treatment(P>0.05).(3)RT-PCR:(1)The MMP-2 expression in granulation tissue of rats wound in MEBO group,bFGF group and control group changed with time are showing a increasing-decreasing trend(P<0.05);Chronic wound group showed a increasing trend(P<0.05);MMP-2 expression of three time points in MEBO group,bFGF group,control group and chronic wound group have significant differences(P<0.05);In the blank group,the rats tissue was normal skin,the expression of MMP-2 was not significantly changed due to the absence of injury treatment(P>0.05).(2)The EGFR expression in granulation tissue of rats wound in MEBO group,bFGF group and control group changed with time are showing a increasing-decreasing trend(P<0.05);Chronic wound group showed a increasing trend(P<0.05);The EGFR expression of three time points in MEBO group,bFGF group,control group and chronic wound group have significant differences(P<0.05);In the blank group,the rats tissue was normal skin,the expression of EGFR was not significantly changed due to the absence of injury treatment(P>0.05).(3)The p-AKT expression in granulation tissue of rats wound in MEBO group,bFGF group and control group changed with time are showing a increasing-decreasing trend(P<0.05);Chronic wound group showed a increasing trend(P<0.05);The p-AKT expression of three time points in MEBO group,bFGF group and control group have significant differences(P<0.05);In the blank group,the rats tissue was normal skin,the expression of p-AKT was not significantly changed due to the absence of injury treatment(P>0.05).Conclusion:(1)MEBO can promote the healing of chronic wound in rats.(2)MEBO can reduce the expression of MMP-2 and MMP-2 mRNA in the granulation tissue of chronic wound.(3)MEBO can increase the expression levels of p-AKT,EGFR,AKT mRNA,EGFR2 mRNA in granulation tissue of chronic wound.(4)MEBO may promote the wound angiogenesis by activating the AKT signaling pathway in order to increasing the expression of EGFR to promote the wound healing and reducing MMP-2 in order to prevent the EMC degradation.