Antiproliferation of keratinocytes and alleviation of psoriasis by the ethanol extract of Artemisia capillaris

The therapeutic potentials of the ethanol extract of Artemisia capillaris (ACE) for psoriasis were verified in HaCaT cells (as an immortalized human keratinocyte cell line) and imiquimod (IMQ)‐induced psoriasis‐like mouse models. In HaCaT cells, IC₅₀ value of ACE was 37.5 μg/ml after incubating for 72 hr. The antiproliferation activity of ACE in HaCaT cells was further verified by apoptosis assays. The percentage of apoptotic population in ACE‐treated group was significantly higher than that of control group (p < .05). The result of cell cycle arrest assay also supported the observed antiproliferation efficacy of ACE in HaCaT cells. In IMQ‐induced psoriasis‐like mouse models, the Psoriasis Area and Severity Index score of ACE (50 mg/ml; ACE50)‐treated group was significantly lower than that of IMQ group on Day 4 (p < .05). After topical application of ACE on psoriasis‐like lesion for 4 days, the epidermal thickness of (IMQ + ACE50) group was significantly lower than that of IMQ group (p < .05). The expression levels of Ki‐67 and intracellular adhesion molecule‐1 in excised skin tissues of (IMQ + ACE50) group were also lower than those of IMQ group. All these findings suggest that ACE can be used as a promising antipsoriatic agent.