Steroidal Saponins from the Rhizomes of Smilax china and Their Inhibitory Effects on Lipopolysaccharide-Induced Proinflammatory Cytokines Expression.

ABSTRACT

Four new furostanol saponins (1  - 4 ) and a new pregane-type saponin (5 ) along with six known steroidal saponins (6  - 11 ) were isolated from the rhizomes of Smilax china. The structures of 1  - 5 were elucidated by extensive analysis of NMR and HR-ESI-MS data in addition to enzymatic hydrolysis and other chemical methods. Compounds 1, 4 , and 11 showed inhibitory activity against the expression of proinflammatory mediators, inducible nitric oxide synthase, interleukin-1ß, interleukin-6, and tumor necrosis factor-α in lipopolysaccharide-induced RAW264.7 cells. Compound 1 , at a concentration of 20 µM, decreased the production of inducible nitric oxide synthase, interleukin-1ß, interleukin-6, and tumor necrosis factor-α by 36, 62, 72, and 67%, respectively, which is comparable to that of the positive control dexamethasone.