Plant extracts from stinging nettle (Urtica dioica), an antirheumatic remedy, inhibit the proinflammatory transcription factor NF-κ-B

Activation of transcription factor NF-kappa B is elevated in several chronic inflammatory, diseases and is responsible for the enhanced expression of many proinflammatory gene products. Extracts from leaves of stinging nettle (Urtica dioica) are used as antiinflammatory remedies in rheumatoid arthritis. Standardized preparations of these extracts (IDS23) suppress cytokine production, but their mode of action remains unclear. Here we demonstrate that treatment of different cells with IDS23 potently inhibits NF-kappa B activation. An inhibitory effect nas observed in response to several stimuli, suggesting that IDS23 suppressed a common NF-kappa B pathway. Inhibition of NF-kappa B activation by IDS23 was not mediated by a direct modification of DNA binding, but rather by preventing degradation of its inhibitory subunit I kappa B-alpha Our results suggests that part of the antiinflammatory effect of Urtica extract may be ascribed to its inhibitory effect on NF-kappa B activation, (C) 1999 Federation of European Biochemical Societies.