Cycloartane-type glycosides from Astragalus brachycalyx FISCHER and their effects on cytokine release and hemolysis. (September 2017) - Aslanipour, Behnaz
Graphical abstract: Highlights: Two new cycloartane-type saponins were isolated from Astragalus brachycalyx . The compounds exhibited immunostimulatory activities via inducing IL-2 and IFN-γ release. The new compounds were established on the basis of 1D- and 2D NMR spectroscopy and HR–MS. Abstract: Two new tridesmosidic cycloartane-type triterpene glycosides(1 and2) were isolated from the methanolic extract of the roots of Astragalus brachycalyx FISCHER ( A. brachycalyx ) along with ten (3–12) known cycloartane-type triterpene glycosides. Structures of the new compounds were established as 3- O - β -d -xylopyranosyl-6- O - β -d -glucopyranosyl-16- O - β -d -glucopyranosyl-3β, 6α, 16β, 24( S )-25-pentahydroxycycloartane (1 ), 3- O -[α-l -arabinopyranosyl-(1→2)- β -d -xylopyranosyl]-6- O - β -d -glucopyranosyl-16- O - β -d -glucopyranosyl-3β, 6α, 16β, 24( S )-25-pentahydroxycycloartane (2 ), by using 1D and 2D-NMR techniques and mass spectrometry. In vitro immunomodulatory effects and hemolytic activities of the new saponins (1 and2 ) and acetylated form of1 (1a ) were studied together with the BuOH and MeOH extracts of Astragalus brachycalyx . The results have proven that tridesmosidic Astragalus cycloartanes are noteworthy immunomodulatory compounds via induction of cytokine production, namely IL-2 and IFN-γ. The test compounds also resulted slight hemolysis at very high doses substantiating a safer profile compared to the positive control QS-21.