Experimental Study On The Intervention Of Qingshi Antipruritic Ointment On Epidermal Lipid Synthesis In Mice With Atopic Dermatiti

Objective:To establish a mouse model of atopic dermatitis and evaluate its effectiveness,to explore the effect of Qingshi antipruritic ointment on epidermal lipid in mice with atopic dermatitis,and to explore the possible mechanism of its action on the repair of skin barrier injury.Method:The experiment used 2,4-2 nitro chlorobenzene acetone solution manufacturing model,Balb/c mice of atopic dermatitis by SCORAD scores to determine its symptoms and signs,H-E staining,oil-red O staining and transmission electron microscopy of three methods for organization pathology inspection,to observe the skin pathological tissue morphology in skin lesions,skin and the distribution of the stratum corneum lipids,corneous layer ultrastructure changes,etc.,and to determine its inflammatory change and barrier damage situation,evaluation model.In another part of the experiment,Qingshi antipruritic ointment was applied topically to interfere with atopic dermatitis in a mouse model.HE staining sections of skin lesions,oil red O staining slices and transmission electron microscopy pathological slices were observed under light microscope to observe the damage of dermis,epidermal cells and cuticle,and to compare with the positive drug hydrocortisone butyrate cream to evaluate its efficacy.Result:Balb/c mice with AD was made by hapten DNCB,erythema,papule/edema,furfuration and epidermal exfoliation in model mice all accorded with AD-like lesions.SCORAD score showed that there was a significant difference between the model group and the blank group(P<0.01).There was no significant difference among another three groups(P>0.05).Histopathological results of skin lesions in model mice showed that the epidermis structure was damaged,the function of skin barrier was incompetence,and the function of corneum was damaged.Oil red O staining showed that model group was lighter than blank group and the optical density of cuticle decreased significantly(P<0.01).The lipid content in corneum was significantly decreased and lipid barrier was damaged in model group.Transmission electron microscopy showed that the corneurn of model group was discontinuous,the lamellar structure was not obvious,the keratinocytes arranged disorderly,and the skin barrier function was impaired.The model of AD was successful.Compared with the positive drug hydrocortisone butyrate(Youzhuoer),the effection of Qingshi antipruritic ointment in AD model mice was significant on SCORAD score.Both two drugs were significant effects on erythema,papule/edema,furfuration and epidermal exfoliation in AD model mice(P<0.01).There were no significant difference between the two groups(P>0.05).Histopathologically,HE staining showed that there was no significant infiltration of inflammatory cells in the dermis and epidermis of the two groups,while the infiltration of inflammatory cell in model group was obvious.It suggested that anti-inflammatory therapy is effective.Oil red O staining and the optical density of corneum showed that Qingshi antipruritic ointment could promote the recovery of lipid content in corneum of AD mice model,better than the group of Youzhuoer.Transmission electron microscopy showed that the lamellar structure of the corneum was partially restored in the Qingshi antipruritic group compared with the model group,and the lamellar structure of the corneum,Qingshi antipruritic group was slightly better than that of the Youzhuoer group.Conclusion:Qingshi antipruritic ointment can promote the recovery of epidermal structure and cuticle lipid barrier in atopic dermatitis.