[#1996-03] Poria Nukaya, Haruo et al. Isolation of Inhibitors of TPA-Induced Mouse Ear Edema from Hoelen
Isolation of Inhibitors of TPA-Induced Mouse Ear Edema from Hoelen, Poria cocos
Haruo NUKAYA, Hirokazu YAMASHIRO, Hirotatsu FUKAZAWA, Hitoshi ISHIDA, and Kuniro TSUJI
School of Pharmaceutical Sciences, University of Shizuoka, Japan.
Several anti-inflammatory substances are known to inhibit the action of tumor promoters in two-stage mouseskin carcinogenesis.”) Since anti-inflammatory activity may play an important role in the mechanism of anti-tumor promotion, we have searched for new anti-inflammatory substances among natural products. In this study, inhibitory activities against mouse ear edema were measured in a TPA (12-O-tetradecanoyl phorbol 13-acetate)‑induced inflammation model, because inhibitory potency against TPA-induced inflammation may roughly parallel inhibitory activity against tumor promotion.3‘4)
It has been reported that extracts of traditional Chinese medicines used as anti-inflammatory drugs inhibited TPA-induced inflammation.5) The extract of Hoelen was particularly effective. As active compounds in Hoelen, sixteen triterpene carboxylic acids, i.e., pachymic acid, 3β-hydroxylanosta-7,9(11),24-trien-21-oic acid, etc., have already been reported by Yasukawa et a1.6‘71 Here, we describe the isolation of four active compounds from Hoelen, in addition to compounds reported previously, and the determination of their chemical structures.
In our studies on Hoelen, bioassay- and TLC-guided fractionation of the methanol extract by silica gel column chromatography led to an active fraction that did not contain pachymic acid, 3β-hydroxylanosta-7,9(11),24- trien-21-oic acid, etc. Compounds 1-5 were isolated from this fraction by means of HPLC.
