Artemisia capillaris inhibits atopic dermatitis-like skin lesions in Dermatophagoides farinae-sensitized Nc/Nga mice

Background: Artemisia capillaries Thunb. (AC) has been used to treat inflammatory and hepatic disorders such as hepatic injury, hepatic fibrosis and hepatitis. However, the efficacy of AC against atopic dermatitis (AD), an inflammatory disease, has not been examined. In the present study, AC was evaluated for anti-inflammatory and anti-AD effects using both in vitro and in vivo systems. Methods: The contents of six compounds (chlorogenic acid, caffeic acid, isochlorogenic acid A, hyperoside, isoquercitrin and scoparone) in AC were simultaneously assayed using HPLC system. To evaluate the anti-inflammatory effect of AC, NO production was measured in RAW264.7 cell stimulated with 1 mu g/mL LPS. Histamine levels were assayed in MC/9 cells stimulated with 50 nM PMA and 1 mu M A23187. To examine the role of AC in vivo, AC (10 mg/mouse/day) was topically applied for four weeks the back and ears of Dermatophagoides farinae-sensitized Nc/Nga mice. Protopic ointment (0.1% tacrolimus) was used as a positive control. Results: The contents of the six components in AC range from 0.44 to 43.14 mg/g. Chlorogenic acid (21.06 +/- 0.08 mg/g) and isochlorogenic acid A (43.14 +/- 0.12 mg/g) were major components in AC. AC inhibited NO and histamine production in cells respectively. In D. farinae-sensitized Nc/Nga mice, the topical application of AC reduced dermatitis scores, hemorrhage, hypertrophy and hyperkeratosis of the epidermis in the dorsal skin and ear. The treatment of AC also reduced the plasma levels of histamine (1.5 fold) and IgE (1.4 fold). Conclusions: Our results suggest that AC should be explored as a potential therapeutic agent to treat atopic dermatitis and analysis by HPLC will help to improve the quality of AC.