022 The suppressive effect of kaempferol on type 2 inflammation in atopic dermatitis in mouse model

Atopic dermatitis is a chronic relapsing inflammatory common skin disease. It has a complex pathophysiology, that involves a strong genetic predisposition, epidermal dysfunction, and type 2 inflammation. Kaempferol is a natural flavonoid widely found in tea, vegetables, and fruits. It has a wide range of beneficial pharmacological activities, including excellent anti-oxidation and anti-inflammation. However, the therapeutic effect of kaempferol on atopic dermatitis was unclear. We aimed to elucidate the effect of kaempferol on skin inflammation in atopic dermatitis and its inhibitory mechanism on skin inflammation. We assessed the suppressive effect of administration of kaempferol on skin inflammation in calcipotriol-induced atopic dermatitis-like skin inflammation mouse model was investigated, and quantification of skin dermatitis and TEWL were performed. Histopathological study showed the expression of TSLP, cornified envelope proteins such as filaggrin, loricrin and involucrin, and the numbers of infiltrating inflammatory cells including lymphocytes, macrophages, and mast cells into the dermatitis area. The expression of IL4 and IL13 were investigated by real-time PCR and flow cytometry analysis using skin tissue. It was found that kaempferol treatment significantly suppressed calcipotriol-induced dermatitis, TEWL and infiltration of inflammatory cells (p<0.05). Kaempferol treatment improved the decreased filaggrin, loricrin and involucrin expression in calcipotriol-induced dermatitis skin site (p<0.05). The expression of TSLP, IL4 and IL13 were partially decreased in mice treated with kaempferol (p<0.05). It seemed that kaempferol might improve calcipotriol-induced dermatitis via suppression of inflammation and improvement of barrier dysfunction. Kaempferol might have the potential to be a new treatment for atopic dermatitis.