Diarylheptanoids from Alnus hirsuta inhibit the NF-kB activation and NO and TNF-alpha production.

Six diarylheptanoids (1-6) from the stem bark of Alnus hirsuta were investigated for their inhibitory activity against LPS-induced NF-kB activation and NO and TNF-alpha production. Among them, compounds 2, 3, and 6 displayed inhibitory activity against NF-kB activation and NO and TNF-alpha production with IC50 values of 9.2-9.9 microM, 18.2-19.3 microM, and 22.3-23.7 microM, respectively, in RAW264.7 cells. Three active compounds had no significant cytotoxicity in RAW264.7 cells at their effective concentrations. This is the first report of NF-kB-inhibitory activity of these compounds and supports the pharmacological use of A. hirsuta, which has been employed as a herbal medicine for the treatment of inflammatory diseases.