Evodiae Fructus extract suppresses inflammatory response in HaCaT cells and improves house dust mite-induced atopic dermatitis in NC/Nga mice

This study was conducted to assess the effect of Evodiae Fructus 70% ethanol extract (EFE) on the pathology of atopic dermatitis using in vitro and in vivo models. The major compounds in EFE were identified by ultra-performance liquid chromatography with tandem mass spectrometry as rutaecarpine, evodiamine, evodol, dehydroevodiamine, limonin, synephrine, evocarpine, dihydroevocarpine, and hydroxyevodiamine. EFE significantly decreased chemokine levels in tumor necrosis factor-alpha/interferon-gamma-stimulated HaCaT cells. In house dust mite-treated NC/Nga mice, topical application of EFE significantly decreased the dermatitis score, epidermal hyperplasia and thickening, mast cell infiltration, and plasma levels of histamine and corticosterone. Thymic stromal lymphopoietin, CD4+ T cells, interleukin-4, and intercellular adhesion molecule-1 expression in the lesioned skin was reduced in the treated mice. The mechanism of EFE was elucidated using transcriptome analysis, followed by experimental validation using Western blotting in HaCaT cells. EFE down-regulated the activation of Janus kinase (JAK)-signal transducers and activators of transcription (STAT) and mitogen-activated protein kinases (MAPK) signaling pathways in HaCaT cells. EFE improves atopic dermatitis-like symptoms by suppressing inflammatory mediators, cytokines, and chemokines by regulating the JAK-STAT and MAPK signaling pathways, suggesting its use as a potential agent for the treatment of atopic dermatitis.