Yinxie I Formula attenuates imiquimod-induced psoriasis-like skin inflammation via IL-23/IL-17 axis

Psoriasis is considered a chronic inflammatory skin disorder characterized by keratinocytes hyperproliferation. The IL-23/IL-17 immune pathway has been substantiated in numerous studies to be closely associated with psoriasis progression. Yinxie I Formula is a traditional Chinese medicine made from 9 herbal medicines, which has excellent clinical efficacy in psoriasis. However, to date, the mechanism of action of Yinxie I Formula against psoriasis remains unknown. In this perspective, we discuss the efficacy of Yinxie I Formula in mice with imiquimod (IMQ) induced psoriasis. Yinxie I Formula significantly reduced the area of skin lesions and the inflammatory response in mice with psoriasis. Furthermore, Yinxie I Formula alleviated the expression levels of inflammation-related genes IL-6, IL-17 A, IL-22, IL-23, TNF-α and IL-23, IL-18, IL-6 and IL-1β-related proteins and alleviated the abnormal surge of dendritic cells, macrophages and T cells in the skin and spleen. Meanwhile we found that Yinxie I Formula reduced the release of NO, TNF-α, IL-1β and IL-23 in lipopolysaccharide-induced mouse macrophage RAW264.7 cell line. The results suggest that the therapeutic mechanism of Yinxie I Formula may also be correlated with the STAT signaling pathway. We further analyzed the active ingredient of Yinxie I Formula, Buddleoside, which may be the main substance that exerts the therapeutic effect. In conclusion, we have investigated that Yinxie I Formula attenuates the IMQ-induced inflammatory response in psoriasis by inhibiting the IL-23/IL-17 axis, which lays the foundation for the antipsoriasis mechanism and provides a theoretical basis for the clinical promotion of Yinxie I Formula.