Alkaloids from Chelidonium majus and their inhibitory effects on LPS-induced NO production in RAW264.7 cells.

Abstract A new alkaloid, methyl 2′-(7,8-dihydrosanguinarine-8-yl)acetate ( 1 ), together with six known alkaloids, stylopine ( 2 ), protopine ( 3 ), norchelidonine ( 4 ), chelidonine ( 5 ), berberine ( 6 ), and 8-hydroxydihydrosanguinarine ( 7 ), were isolated from Chelidonium majus . Their chemical structures were primarily established using 1D and 2D NMR techniques and mass spectrometry. The anti-inflammatory activity of the isolates was examined for their inhibitory effects on LPS-induced NO production in macrophage RAW264.7 cells. Among them, compounds 5 and 7 showed strong inhibitory activities toward the LPS-induced NO production in macrophage RAW264.7 cells with IC 50 values of 7.3 and 4.5 μM, respectively. In addition, compounds 5 and 7 inhibited the inductions of COX-2 and iNOS mRNA in dose-dependent manners, indicating that these compounds attenuated the syntheses of these transcripts at the transcriptional level.