Evaluation of Artemisia dubia folium extract-mediated immune efficacy through developing a murine model for acute and chronic stages of atopic dermatitis

Background Atopic dermatitis (AD) is a biphasic type of skin inflammation characterized by a predominance of type-2 (T(H)2) and type-1 (T(H)1) helper T cell-biased immune responses at the acute and persistent chronic phases, respectively. The present study was aimed to evaluate the efficacy of Artemisia dubia folium extract (ADFE) on AD-like skin lesions through developing a murine model for acute and chronic stages of AD. To induce acute phase AD, the dorsal skin of BALB/c mice was sensitized twice a week with 1% 2, 4-dinitrochlorobenzene (DNCB), followed by challenge (twice) in the following week with 0.2% DNCB. To induce persistent chronic AD, some mice were challenged twice a week for 4 more weeks. After the second challenge, the dorsal skin was exposed to 3% ADFE (five times per week) for 2 weeks (acute phase) or 4 weeks (persistent chronic phase). Results The paradigm of T(H)2 or T(H)1 predominance at the acute and chronic phase, respectively, was observed in this mouse model. During the acute phase, we observed an increased IL-4/IFN-gamma ratio in splenic culture supernatants, an increased IgG1/IgG2a ratio in serum, and elevated serum IgE levels; however, the skew toward T(H)2 responses was diminished during the chronic stage. Compared with vehicle controls, ADFE reduced the IL-4/IFN-gamma and IgG1/IgG2a ratios in acute AD, but both ratios increased during the chronic stage. Conclusions Our results suggest that ADFE concomitantly suppresses the T(H)2 predominant response in acute AD, as well as the T(H)1 predominant response in chronic AD. Thus, ADFE is a candidate therapeutic for AD.