Effect of six compounds isolated from rhizome of Anemone raddeana on the superoxide generation in human neutrophil

The effect of six compounds isolated from rhizome of Anemone raddeana on the superoxide generation in human neutrophils was investigated. The six compounds examined were 3-acetyloleanolic acid (AOA), oleanolic acid (OA), eleutheroside K (EK), oleanolic acid-3-O-alpha-L-rhamnopyranosyl-(1 --> 2)-[beta-D-glucopyranosyl-(1 --> 4)]-alpha-L-arabinopyranoside (Rd10), raddeanoside 12 (Rd12) and raddeanoside 13 (Rd13). AOA, OA, Rd12 and Rd13 suppressed the superoxide generation induced by N-formyl-methionyl-leucyl-phenylalanine (fMLP) in a concentration-dependent manner. EK and Rd10 significantly enhanced the fMLP-induced superoxide generation in a specific narrow range of low concentration (0.5-0.75 microM), while these compounds more efficiently suppressed the superoxide generation than the other four compounds in other concentrations. In the case of superoxide generation induced by phorbol 12-myristate 13-acetate (PMA), Rd12, OA, EK and Rd10 dose-dependently suppressed the superoxide generation but AOA and Rd13 gave no effect. Arachidonic acid-induced superoxide generation was suppressed by EK, Rd10, Rd12 and Rd13, but was weakly enhanced by AOA and OA. Rd12 dose-dependently inhibited fMLP-induced tyrosyl phosphorylation of 123.0, 79.4, 60.3, 56.2 and 50.1 kDa proteins in human neutrophil. On the other hand, RD10 and EK enhanced the tyrosyl phosphorylation of these proteins in a low concentration range. These phenomena were parallel to the suppression of the fMLP-induced superoxide generations.