Changes And Significance Of The Expression Of LL-37 In Serum Of Rosacea Patients

Background:Rosacea is a common chronic inflammatory skin disease,mainly involving facial blood vessels and hair follicle sebaceous glands.The clinical manifestations are paroxysmal flushing or persistent erythema in the middle of the face,which may be accompanied by telangiectasia,papules,pustules and other symptoms.The pathogenesis of rosacea is not fully understood,and may be related to high temperature or cold stimulation,ultraviolet rays,stress,endocrine disorders,demodex infection,microbial stimulation,genetics,etc..The abnormal activation of innate and acquired immune and neurovascular unbalance are the basis of the pathogenesis of rosacea.It has been reported in the literature that many factors can stimulate the secretion of LL-37 through different ways,improving the activity of LL-37,and promoting the development of the disease.LL-37 is the only cathelicidin found in human body.Its precursor peptide hCAP-18 is treated with kallikrein 5(KLK5)to release the active fragment LL-37.LL-37 can regulate immunity,including leukocyte chemotaxis,angiogenesis and activation of NF-kB,which are related to the morphological features of rosacea,such as facial erythema,telangiectasia,papules,pustular,etc.By confirming that the cathelicidin in rosacea have pathogenic effects,injection of these peptide fragments found in the skin of the patient into the skin of the mouse results in a rosacea-like disease.This may suggest that LL-37 plays a role in the pathogenesis of rosacea,but its specific effects are not clear,and the level of LL-37 in serum of rosacea patients has not been studied.Clinically,it is recommended to use hydroxychloroquine combined with tacrolimus in the treatment of rosacea.However,its role in the mechanism of action on rosacea is still unclear,so we need to continue to study.Objective:To investigate whether there is any difference in serum LL-37 level between rosacea patients and healthy controls.To study the effect of hydroxychloroquine and tacrolimus 0.1%ointment on the expression of LL-37 in serum of rosacea patients,evaluate the efficacy,and provide theoretical basis for the clinical treatment of hydroxychloroquine combined with tacrolimus 0.1%ointment in rosacea patients.Methods:It collected 30 patients(experimental group)and 30 health people(control group)of the dermatological clinic in Zhujiang Hospital.The experimental group were treated with hydroxychloroquine together with tacrolimus 0.1%ointment.The hydroxychloroquine was taken orally,twice a day,every time of 200mg,the tacrolimus 0.1%ointment was applied to the affected part of the face twice a day for 8 weeks.the control group was not treated.2 ml of peripheral blood of patients with rosacea before and after treatment and control group were taken,and the serum LL-37 was detected by ELISA.Results:There was no significant difference in age between the experimental group and the control group(t=-0.306,p>0.05).Compared with the control group,the serum LL-37 was highly expressed in the experimental group before treatment(Z=-6.594,p<0.001).Compared with before treatment,the expression of serum LL-37 was significantly decreased in the experimental group after treatment(t=8.244,)<0.001).Compared with the control group,the serum LL-37 was highly expressed in the experimental group after treatment(Z=-3.711,p<0.001).Conclusion:This study suggests that the pathogenesis of rosacea is closely related to elevated expression level of LL-37.The clinical efficacy of hydroxychloroquine combined with tacrolimus in the treatment of rosacea is exact.The mechanism by which hydroxychloroquine and tacrolimus treat rosacea is inhibiting the expression of LL-37,but not only by inhibiting LL-37.