Counteractive effect of Paeonia lactiflora root constituent mudanpioside E against suppressive effect of Shoseiryuto-extract on passive cutaneous anaphylaxis reaction in mice.

BACKGROUND

Shoseiryuto-extract (SST) is a herbal formula of Japanese traditional kampo medicine used to treat perennial nasal allergy, rhinitis, and bronchial asthma. SST contains eight crude drugs, and is registered in the 16th Edition of Japanese Pharmacopoeia. Previous studies reported anti-allergic effects of SST, but the contribution of the eight crude drugs in SST on these effects has not been evaluated. In the present study, we evaluated the contribution of the eight crude drugs in SST on anti-allergic effect using passive cutaneous anaphylaxis (PCA) reaction in mice.

METHODS

The mixture of crude drugs was decocted in water and lyophilized to prepare SST. To evaluate the active ingredients, compositions of crude drugs were modified and decocted. The PCA reaction was induced by intravenous injection of ovalbumin (OVA) and Evans blue 48 h after intracutaneous injection of anti-OVA serum in mice ears. The crude drug extract was orally administered to overnight-fasted mice 2h before induction of the PCA reaction. Ears were removed 30 min after induction, and the amount of Evans blue present was measured.

RESULTS

Oral administration of SST suppressed the PCA reaction in a dose-dependent manner. Among the eight crude drugs comprising SST, Asiasarum root, Pinellia tuber, and Glycyrrhiza contributed positively, and Peony root contributed negatively to the anti-allergic effects of SST. We isolated mudanpioside E from the extract of Peony root as the counteracting ingredient to exhibit the anti-allergic effects of Peony root-depleted SST.

CONCLUSIONS

When we used SST for the treatment of allergic diseases, removal of Peony root from the traditional formula could augment its effect.