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

The topical anti-inflammatory activity of a germacrane derivative [1,4-dihydroxy-germacra-5E-10(14)-diene; DHGD] isolated from Achillea pannonica Scheele (Asteraceae) was investigated employing the Croton oil-induced dermatitis in the mouse ear. Its effects on the oedematous response and on leukocytes infiltration are described. The germacrane derivative significantly inhibited 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 oedematous response (61%) higher than that induced by an equimolar dose of indomethacin (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 that of the equimolar dose of indomethacin (51% inhibition) also on granulocytes recruitment at the site of inflammation. Hydrocortisone (0.10 mu mol/cm(2)) reduced the cellular infiltrate by 44%.