Six dammarane-type saponins were extracted from steamed Panax notoginseng. Their chemical structures were identified spectroscopically as ginsenosides Rh1 (1), Rg1 (2), 20 (S)-Rg3 (3), 20 (R)-Rg3 (4), Rb3 (5), and Rb1 (6). Compounds (0.1-10 μM) were tested for inhibition of tumor necrosis factor-α (TNF)-induced nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) luciferase reporter activity using a human kidney 293T cell-based assay. Ginsenoside Rb3 (5) showed the most significant activity with an IC50 of 8.2 μM. This compound also inhibited the induction of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) messenger Ribonucleic acid (mRNA) in a dose-dependent manner after HepG2 cells had been treated with TNF-α (10 ng/mL).
Keywords: Antitumor; Panax notoginseng; dammarane-type ginsenoside; inhibitory activity.