Sesquiterpene lactones from Dimerostemma species (Asteraceae) and in vitro potential anti-inflammatory activities

Abstract

Two Brazilian species of Dimerostemma (Asteraceae) were chemically investigated. Two known sesquiterpene lactones (STLs), a germacrolide and an eudesmanolide, were isolated from D. episcopale while D. brasilianum afforded the new germacranolide 1β,5β,10α-trihydroxy-8α- angeloyloxy-germacra-3,11(13)-dien-6α,12-olide in addition to a known one. Structure identification based on NMR and MS analyses. 1β,10α, 4α,5β-Diepoxy-8α-angeloyloxy-costunolide isolated from D. brasilianum was studied for its anti-inflammatory activity. This STL completely inhibited DNA binding of the transcription factor NF-κB at a concentration of 5 μM and 10 μM in Jurkat T and Raw 264.7 cells, respectively. Elastase release from human neutrophils was reduced to 50% at a concentrations of 23 μM after stimulation with PAF and of 27 μM after stimulation with fMLP without showing cytotoxic effects. Additionally, elastase was also directly inhibited. © 2006 Verlag der Zeitschrift für Naturforschung.