FEBS Lett. 1997 Jan; 402(1): 85-90.

Sesquiterpene lactone containing Mexican Indian medicinal plants and pure sesquiterpene lactones as potent inhibitors of transcription factor NF-kappaB.

Bork PM, Schmitz ML, Kuhnt M, Escher C, Heinrich M.

Institute of Pharmaceutical Biology, Albert-Ludwigs University, Freiburg, Germany.

The potential inhibitory effect of 54 Mexican Indian medicinal plants on the activation of transcription factor NF-kappaB was studied. Band-shift experiments identified the ethanolic leaf extracts of Artemisia ludoviciana ssp. mexicana, Calea zacatechichi, and Polymnia maculata (all rich in sesquiterpene lactones) as inhibitors of NF-kappaB down to a concentration of 25 microg/ml. The sesquiterpene lactones isohelenin and parthenolide prevented NF-kappaB activation completely as low as 5 microM. Treatment of HeLa cells with leaf extract of A. ludoviciana ssp. mexicana, isohelenin and parthenolide prevented the induction of transcription on the IL-6 promoter. These experiments identify the eudesmanolide and germacranolide type of sesquiterpene lactones as potent non-antioxidant inhibitors of NF-kappaB. All plants active in the NF-kappaB assay also showed a delay in the onset of capillary reactions of the allantois membrane in a physiological model for anti-inflammatory activity - the HET-CAM assay.