The Effect Of Dexamethasone On Asthma Airway Remodeling And Expression Of Epidermal Growth Factor And Interleukin-8

Objective:To observe the expression of Epidermal Growth Factor(EGF)and interleukin-8in bloodserum of airway remodeling rat models.Exploring not only the relationship between theexpression of them and the airway remodeling degree,but also the effects of airway remodelingof asthma with the dexamethasone late phase．Methods:Forty clean male wistar rats were randomly divided into4groups：modeling group(Ngroup);control group(C gronp);early-interventional group(E group);late-inerventional group(Lgroup)．Each group contained ten rats．To establish the model of airway remodeling ofasthma,each rat in groups E,N and L used intraperitoneal injection with10％ovalbumin(OVA)antigen suspension.Then,in the hermetic container,the rats of the groups used ultrasonicatomizing inhalation with1％ovalbumin(OVA)to sensitize and stimulate asthma.Each rat in theE group from the beginning and the L group from the fifteenth day used the dexamethasone(0.5mg/k g)intraperitoneal injection one hour before ultrasonic atomizing inhalation of OVA.Sodium chloride been used instead of OVA and dexamethasone in Control group.Theexpression of EGF in blood serum was measured by ELISA method.Lung tissues were slicedand hematoxylin and eosin stained.The airway morphological parameters were measured bycomputer image analysis of software.The amount of EGF in the lung tissues been detected byimmunology methods.The data was analyzed by SPSS17.0．Results:The various remodeling in airway were observed at all of the rats except the C group.，Theexpression of IL-8、EGF in astmatic rats were much higher than the control group rats(p<0.05).While compare with the N group remodeling in airway was less and he expression of IL-8、EGF were much lower(p<0.05).The expression of IL-8、EGF in E group were lower andthe thicknesses of bronchus wall and airway smooth muscle were significantly thinner in E groupthan those in L group and N group(p<0.05)The amount of IL-8in the serum and EGF arerelated with the rat bronchial airway remodeling degreen.(P<0.001)Conclusions:We proved that the use of dexamethasone can inhibit the development of airway remodelingand the earlier we start dexamethasone using the better it effects;we also found that the amount of IL-8and EGF are correlation with the rat bronchial airway remodeling degree,then weindicate that dexamethasone by lowing the expression of IL-8and EGF to interfere the airwayremodeling process,IL-8and EGF also can been used as one of the indicators to measureairway remodeling severity.