Topical anti-inflammatory activity of a new germacrane derivative from Achillea pannonica

The topical anti-inflammatory activity of a germacrane derivative [1,4-dihy droxy-germacra-5E-10(14)-diene; DHGD] isolated from Achillea pannonica Sche ele (Asteraceae) was investigated employing the Croton oil-induced dermatit is in the mouse ear. Its effects on the oedematous response and on leukocyt es infiltration are described. The germacrane derivative significantly inhi bited ear oedema in a dose-dependent manner, with an ID50 of 0.40 mu mol/cm (2). DHGD (0.75 mu mol/cm(2)) provoked a global inhibition of the oedematou s response (61%) higher than that induced by an equimolar dose of indometha cin (43%) within 24 hours; the reduction induced by hydrocortisone (0.10 mu mol/cm(2)) was 68%. The effect of DHGD (61% inhibition) was higher than th at of the equimolar dose of indomethacin (51% inhibition) also on granulocy tes recruitment at the site of inflammation. Hydrocortisone (0.10 mu mol/cm (2)) reduced the cellular infiltrate by 44%.