Anti-allergic and anti-inflammatory effects of butanol extract from Arctium Lappa L

BACKGROUND Atopic dermatitis is a chronic, allergic inflammatory skin disease that is accompanied by markedly increased levels of inflammatory cells, including eosinophils, mast cells, and T cells. Arctium lappa L. is a traditional medicine in Asia. This study examined whether a butanol extract of A. lappa (ALBE) had previously unreported anti-allergic or anti-inflammatory effects. METHODS This study examined the effect of ALBE on the release of β-hexosaminidase in antigen-stimulated-RBL-2H3 cells. We also evaluated the ConA-induced expression of IL-4, IL-5, mitogen-activated protein kinases (MAPKs), and nuclear factor (NF)-κB using RT-PCR, Western blotting, and ELISA in mouse splenocytes after ALBE treatment. RESULTS We observed significant inhibition of β-hexosaminidase release in RBL-2H3 cells and suppressed mRNA expression and protein secretion of IL-4 and IL-5 induced by ConA-treated primary murine splenocytes after ALBE treatment. Additionally, ALBE (100 μg/mL) suppressed not only the transcriptional activation of NF-κB, but also the phosphorylation of MAPKs in ConA-treated primary splenocytes. CONCLUSIONS These results suggest that ALBE inhibits the expression of IL-4 and IL-5 by downregulating MAPKs and NF-κB activation in ConA-treated splenocytes and supports the hypothesis that ALBE may have beneficial effects in the treatment of allergic diseases, including atopic dermatitis.