Yu-ping-feng-san (YPFS) is a Chinese medical formula that is used clinically for allergic diseases and characterized by reducing
allergy relapse. Our previous studies demonstrated that YPFS efficiently inhibited T helper 2
cytokines in allergic
inflammation. The underlying mechanisms of action of YPFS and its effective components remain unclear. In this study, it was shown that YPFS significantly inhibited production of
thymic stromal lymphopoietin (TSLP), an epithelial cell-derived initiative factor in allergic
inflammation, in vitro and in vivo. A method of human bronchial epithelial cell (16HBE) binding combined with HPLC-MS (named 16HBE-HPLC-MS) was established to explore potential active components of YPFS. The following five components bound to 16HBE cells: calycosin-7-glucoside,
ononin, claycosin, sec-o-glucosylhamaudol and
formononetin. Serum from YPFS-treated mice was analyzed and three major components were detected claycosin,
formononetin and
cimifugin. Among these, claycosin and
formononetin were detected by 16HBE-HPLC-MS and in the serum of YPFS-treated mice. Claycosin and
formononetin decreased the level of TSLP markedly at the initial stage of allergic
inflammation in vivo. Nuclear factor (NF)-κB, a key
transcription factor in TSLP production, was also inhibited by claycosin and
formononetin, either in terms of transcriptional activation or its nuclear translocation in vitro. Allergic
inflammation was reduced by claycosin and
formononetin when they are administered only at the initial stage in a murine model of atopic
contact dermatitis. Thus, epithelial cell binding combined with HPLC-MS is a valid method for screening active components from
complex mixtures of Chinese medicine. It was demonstrated that the compounds screened from YPFS significantly attenuated allergic
inflammation probably by reducing TSLP production via regulating NF-κB activation.