GPS-1-1

Traditional Chinese medicine Glycyrrhiza uralensis (G. uralensis) exerts anti-inflammatory and anti-allergic effects. However, there is currently no valid evidence regarding its anti-histamine effect. This study aimed to elucidate the antihistamine effect of Glycyrrhiza uralensis Fisch essential oils (GUEOs) and glabridin (Gla) extracted from G. uralensis in SPF KM mice and investigate the underlying mechanisms. The chemical components of GUEOs were analyzed using gas chromatography-mass spectrometry (GC-MS), and quality control was conducted. An acute histamine allergy model was established in SPF KM mice following one week of continuous histamine administration. Scratching behavior and appearance of back scratches were observed. Hematoxylin and eosin staining was used to detect the thickness of the mouse dermis. Toluidine blue staining was performed on dermal tissues to count the number of mast cells. Immunohistochemistry was used to determine the integrated optical density (IOD) values of nerve growth factor (NGF) and interleukin-1β (IL-1β). Quantitative Real-time polymerase chain reaction (qRT-PCR) was used to determine the relative intensity of IL-4 and IL-6. Enzyme-linked immunosorbent assay (ELISA) was employed to detect the content of interferon-γ (IFN-γ)，IL-1 and filaggrin (FLG). Compared with the model group, both the GUEOs and Gla groups exhibited reduced scratching behavior in mice, accompanied by epidermal thinning, decreased mast cell numbers, downregulated expression of IL-1β, NGF, IL-4, IL-6, IFN-γ, and IL-1, and upregulated FLG expression. We showed that GUEOs and Gla exert a favorable inhibitory effect on histamine-induced allergic inflammation in mice, suggesting that G. uralensis can serve as a promising natural anti-histamine agent.