Anti-inflammatory glycoterpenoids from Scrophularia auriculata

The activity of the four glycoterpenoids: two saponins, verbascosaponin A a nd verbascosaponin, and two iridoids, scropolioside A and scrovalentinoside , isolated from Scrophularia auriculata ssp. pseudoauriculata, were studied in different models of acute and chronic inflammation. Both saponins signi ficantly inhibited the mouse paw edema induced by carrageenan and ear edema induced by single and multiple doses of 12-O-tetradecanoylphorbol 13-aceta te (TPA). Verbascosaponin A showed a potency twice as high as that of indom ethacin in the acute TPA model. Verbascosaponin A and scropolioside A were active after a long latency period against ethyl phenylpropiolate edema, as are glucocorticoids. When the putative corticoid-like mechanism of the two compounds was studied, verbascosaponin A activity was notably reduced by t he mRNA synthesis inhibitor, actinomycin D, while the effect of scropoliosi de A was partially interfered with by the anti-glucocorticoid drugs used. B oth iridoids were active on the delayed type hypersensitivity reaction. The y significantly reduced the inflammatory lesion and suppressed the cellular infiltration. (C) 2000 Elsevier Science B.V. All rights reserved.