摘要:In the course of our research on the oligoglycosidic constitutents of Turkish Astragalus species, we have isolated a number of cycloartane-type triterpene glycosides. The current study examines the immunostimulatory effects of nineteen of these cycloartane-type compounds using a transcription-based bioassay for Nuclear Factor kappa B (NF-κB) activation in a human macrophage/monocyte cell line, THP-1. All compounds were inactive at 100 μg/ml except astragaloside I which increased NF-κB directed luciferase expression to levels about 65% as compared with maximal stimulation by E. coli lipopolysaccharide (LPS) at 10 μg/ml. None of the compounds were active at low dosage levels (0.1 μg/ml) in combination with 50 ng/ml LPS. Astragaloside I also increased mRNA expression of the inflammatory cytokines interleukin-1β(IL-1β) and tumor necrosis factor-α (TNF-α) as measured using reverse transcriptase-polymerase chain reaction (RT)-PCR. Based on these results it is clear that certain structural features are required for immunostimulation of cycloartane-type triterpene glycosides.
关键词:Astragalus;immunostimulatory;astragaloside I;macrophage;THP-1;nuclear factor kappa B (NF-κB)