Chemical composition-based characterization of the anti-allergic ef- fect of Guominkang Formula on IgE-mediated mast cells activation and passive cutaneous anaphylaxis

Guominkang (GMK), a Chinese medicine formula, has been used to treat allergic diseases in clinical settings for many years. To evaluate the antiallergic effect and molecular mechanism of action of GMK extract, RBL-2H3 cell models and passive cu-taneous anaphylaxis (PCA) mouse models were established. High performance liquid chromatography (HPLC) and ultra-high perform-ance liquid chromatography-mass spectrometry (UHPLC-MS) analyses were performed to characterize the chemical composition of GMK. A total of 94 compounds were identified or tentatively identified from GMK. Three of them, emodin, ursolic acid, and hama-udol, were identified for the first time as potential active compounds in GMK, since they inhibited the degranulation of mast cells. The anti-allergic effect of hamaudol was the first to be discovered. GMK could markedly mitigate the shade of Evans Blue extravasation and ear incrassation in PCA mouse models. Additionally, GMK significantly inhibited the degranulation of mast cells, suppressed mast cell degranulation by reducing Ca2+influx and the levels of TNF-alpha, IL-4, and histamine, and markedly inhibited the phosphorylation of Lyn, Syk, PLC gamma 1, I kappa B alpha, and NF-kappa B p65. Molecular docking results indicated that hamaudol and emodin had strong interaction with Fc RI and NF-kappa B related proteins, while ursolic acid only interacted with NF-kappa B associated proteins. These results suggest GMK sup-presses the activation of MCs both in vivo and in vitro. The underlying mechanism of its anti-allergic activity is associated with the in-hibition of Fc RI and NF-kappa B activation.