NF-κB inhibitory activities of glycosides and alkaloids from zanthoxylum schinifolium stems

Zanthoxylum schinifolium is an aromatic shrub, the pericarp and leaves of which are widely used in culinary applications in East Asian countries. In the present study, one new neolignan glycoside, zanthoxyloside A (1) together with 16 known glycosides (2-12) and alkaloids (13-17), were isolated from methanol extract of the stems of Z. schinifolium. The absolute configuration of one known monoterpenoid glycoside (2) was determined. The structures of the isolated compounds were established by one dimensional (1D), 2D NMR and mass spectrometry. The nuclear factor-κB (NF-κB) inhibitory activities of the isolated compounds stimulated with tumor necrosis factor alpha (TNFa) were measured using a luciferase reporter system. Compounds 1, 5, 16, and 17 exhibited significant inhibition of NF-κB activation in a dose-dependent manner. Furthermore, compounds 1, 5, 16, and 17 inhibited TNFa-induced expression of inducible nitric oxide synthase (iNOS) and intercellular adhesion molecule-1 (ICAM-1) mRNA and dose-dependent inhibition of iNOS promoter activity.