Sauchinone, a Lignan from Saururus chinensis, Suppresses iNOS Expression through the Inhibition of Transactivation Activity of RelA of NF-kB

Sauchinone, a known lignan, was isolated from the root of Saururus chinensis as an active principle responsible for inhibiting the production of NO in LPS-stimulated RAW264.7 cells by activity-guided fractionation. Sauchinone dose-dependently inhibited not only the production of NO, but also the expression of iNOS mRNA and protein in LPS-stimulated RAW 264.7 cells. Furthermore, sauchinone prevented LPS-induced NF-kB activation, which is known to play a critical role in iNOS expression, assessed by a reporter assay under the control of NF-kB. (omitted)