Dammarane-type saponins with proprotein convertase subtilisin/kexin type 9 inhibitory activity from Gynostemma pentaphyllum

Seven undescribed dammarane-type saponins, gypenosides LXXXI-LXXXVII, together with four known compounds, were isolated from the whole herb of Gynostemma pentaphyllum. The chemical structures of these undescribed compounds were elucidated on the basis of physical and spectroscopic analysis and comparison with literature data. All the isolates were evaluated for their proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitory activities in HepG2 cells. Among them, gypenosides LXXXII-LXXXVII, gynosaponin II, IV and VI suppressed the expression of PCSK9 in LPDS-induced HepG2 cells at 20 μM; gypenosides LXXXII, LXXXV and LXXXVII showed inhibitory activities against PCSK9 at 10 μM; notably, gypenoside LXXXII still exhibited inhibitory activity against PCSK9 at 5 μM.