Deoxypodophyllotoxin (DPT), a naturally occurring flavolignan with anti-inflammatory
activity, was isolated from Anthriscus sylvestris Hoffm., and we examined its effects on the expression of inducible nitric oxide synthase
(iNOS) in lipopolysaccharide (LPS)-stimulated, murine macrophage-like RAW264.7 cells.
Western blot analysis performed with specific anti-iNOS antibodies showed that a decrease
in nitric oxide (NO) was accompanied by a decrease in the iNOS protein level. To clarify
the mechanistic basis for DPT's ability to inhibit iNOS induction, we examined the
effect of DPT on NF-κB transcriptional activity and DNA binding activity. DPT potently
suppressed both reporter gene activity and DNA binding activity. These findings suggest
that DPT in RAW264.7 cells abolished LPS-induced iNOS expression by inhibiting the
transcription factor, NF-B.
Acknowledgements: This work was supported by Korea Research Foundation Grant (KRF-2006–005-J01102).
References: 1. Lin C. X. et al. (2004) Planta Med. 70:474–476.
2. Lee S. H., et al. (2004) Biol. Pharm. Bull. 27:786–788.
3. Lin C. X. et al. (2006) Planta Med. 72: 786–791.