Immunostimulatory effects of cycloartane-type triterpene glycosides from astragalus species.
In the course of our research on the oligoglycosidic constituents 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-kappaB) activation in a human macrophage/monocyte cell line, THP-1. All compounds were inactive at 100 microg/ml except astragaloside I which increased NF-kappaB directed luciferase expression to levels about 65% as compared with maximal stimulation by E. coli lipopolysaccharide (LPS) at 10 microg/ml. None of the compounds were active at low dosage levels (0.1 microg/ml) in combination with 50 ng/ml LPS. Astragaloside I also increased mRNA expression of the inflammatory cytokines interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) 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.
Bedir
E
E
National Center for Natural Products Research, Research Institute of' Pharmaceutical Sciences,The University of Mississippi, 38677, USA.
Pugh
N
N
Calis
I
I
Pasco
D S
DS
Khan
I A
IA
D000276:Adjuvants, Immunologic / Q000494:pharmacology*; D002478:Cells, Cultured; D006027:Glycosides / Q000737:chemistry / Q000494:pharmacology*; D006801:Humans; D008262:Macrophage Activation / Q000187:drug effects; D008264:Macrophages / Q000187:drug effects* / Q000276:immunology; D019684:Magnoliopsida / Q000737:chemistry*; D016328:NF-kappa B / Q000378:metabolism; D012503:Saponins / Q000737:chemistry / Q000494:pharmacology; D014315:Triterpenes / Q000737:chemistry / Q000494:pharmacology*
D000276:Adjuvants, Immunologic; D006027:Glycosides; D016328:NF-kappa B; D012503:Saponins; D014315:Triterpenes; C085352:cycloartane