摘要Objective:Psoriasis is a common chronic inflammatory skin disease that is prone to recurrence,and the proinflammatory factor,cysteine-rich protein 61(Cyr61),is important in its pathophysiology.Long-term clinical practice has shown that Sancao Formula(SC),a Chinese herbal compound,is effective in the treat-ment of psoriasis,but the precise mechanism remains unknown.In this study,we investigate the mech-anism by which SC extract alleviates imiquimod(IMQ)-induced psoriasis.Methods:The expression of Cyr61 in psoriatic lesions and normal healthy skin was detected using immunohistochemical analysis to investigate the biological role of Cyr61 in models of psoriatic inflam-mation.A psoriatic mouse model was established by topical application of IMQ,and the effect of topical application of SC extract was evaluated using the psoriasis area and severity index(PASI)score,hematoxylin-eosin staining,and histopathological features of the skin.Next,a HaCaT cell inflammation model was established using interferon-γ(IFN-γ),and the effect of SC extract on the mRNA and protein levels of Cyr61 and intercellular cell adhesion molecule-1(ICAM-1)was confirmed using Western blot and quantitative real-time polymerase chain reaction analyses.Results:Immunohistochemical staining showed that the expression of Cyr61 in psoriatic lesions was higher than that in normal skin samples(78.26％vs 41.18％,P＜0.05),and the number of Cyr61-positive cells in psoriatic lesions was also significantly higher than in normal skin(18.66±2.51 vs 4.33±1.52,P＜0.05).Treatment in mice with IMQ-induced psoriasis showed that SC extract could sig-nificantly improve the inflammatory phenotype,PASI score(10.875±0.744 vs 3.875±0.582,P＜0.05),and pathological features compared with those in IMQ model group;SC treatment was also associated with decreased levels of Cyr61 and ICAM-1.In the IFN-γ-induced inflammatory cell model,the mRNA and protein levels of Cyr61 and ICAM-1 were upregulated,while the SC extract downregulated the levels of Cyr61 and ICAM-1.Conclusion:The results provide a theoretical basis for the involvement of Cyr61 in the pathogenesis of psoriasis,and suggest that SC should be used to target Cyr61 for the prevention of psoriasis recurrence.