Abstract
The root cortex of Paeonia suffruticosa Andrews (PSA), also known as Moutan Cortex, is known to have anti-allergic and anti-inflammatory properties. This study investigates the effect and mechanism of PSA by in vivo and in vitro methods. Treatings the root cortex from PSA with up to 0.4 mg/ml of an ethanol extract showed no cytotoxicity in human mast cells. The ethanol extract of PSA (200 mg/kg) significantly inhibited the passive cutaneous anaphylaxis reaction in vivo, and suppressed the release of histamine from rat peritoneal mast cells induced by compound 48/80. It was also found that PSA decreased the expressions of TNF-alpha and IL-6 in PMA- and A23187-stimulated HMC-1 cells. The results show the inactivation of IkappaB-alpha and NF-kappaB, as well as suppression of the phosphorylation of extracellular signal-regulated kinase (ERK). Our findings therefore suggest that PSA could be promising for anti-allergic inflammation by inhibiting the NF-kappaB/IkappaB-alpha signaling pathway and the phosphorylation of ERK.