Objective:To elucidate the mechanisms of 4 effective components from a Chinese medicine formula,namely Qingre Huoxue Jiedu Formula(QHJ heat-and toxin-clearing and blood-activating formula),in the treatment of nerve growth factor(NGF)-induced psoriasis.Methods:Keratinocyte proliferation and T cell proliferation models were developed using NGF.An NGF solution(NGF+DMEM,100 ng/mL)was added to all induced groups and treated groups and were cultured for 24 h,while a solution with NTRK1 antagonist(K252a+DEME,300 nmol/L)was added and cultured for 1 h.The models were used to evaluate the effects of the treatment with each of the 4 components of QHJ,namely shikonin,paeonol,astilbin and ursolic acid.Cell apoptosis and proliferation were measured by flow cytometry analysis and CCK8 assay,respectively.The mRNA expression levels of Bax,Bcl-xl,and NGF receptor(NGFR)were assessed by quantitative real-time PCR(qRT-PCR)and Western blot analysis,respectively.Results:(1)All QHJ-treated groups showed significantly increased cell apoptosis and inhibition of cell proliferation compared with the NGF-induced groups(P＜0.05).In addition,treatment with QHJ plus NTRK1 significantly enhanced cell apoptosis and inhibition of cell proliferation compared with cells treated with QHJ only(P＜0.05),particularly in cells treated with ursolic acid.(2)QHJ-treated groups showed higher protein expression levels of Bax,Bcl-xl compared with other groups(P＜0.05).Additionally,treatment with QHJ plus NTRK1 significantly increased the protein expression levels of Bax,Bcl-xl and NGFR compared with those treated with QHJ only(all P＜0.05),especially in those treated with shikonin.Conclusion:The action mechanism of QHJ on psoriasis might be through enhancing cell apoptosis and inhibition of cell proliferation,and upregulating the expression level of Bax,Bcl-xl and NGFR.