20(S)-Protopanaxadiol Saponins Mainly Contribute to the Anti-Atherogenic Effects of Panax notoginseng in ApoE Deficient Mice

Atherosclerosis mainly contributes to cardiovascular disease, a leading cause of global morbidity and mortality. Panax notoginseng saponins (PNS) are proved to therapeutically attenuate the formation of atherosclerotic lesions. According to different sapogenin, PNS are generally classified into 20(S)-protopanaxadiol saponins (PDS) and 20(S)-protopanaxatriol saponins (PTS). It was reported that PDS and PTS might exert diverse or even antagonistic bioactivities. In this study, the probable effects of PTS and PDS on atherosclerotic development were investigated and compared in ApoE-deficient mice (ApoE(−/−)). Male mice were gavaged daily by PNS (200 mg/kg/d), PTS (100 mg/kg/d), or PDS (100 mg/kg/d), respectively for eight weeks. The treatments of PNS and PDS, but not PTS, showed decreased atherosclerotic lesions in the entire aorta by 45.6% and 41.3%, respectively, as evaluated by an en-face method. Both PNS and PDS can improve the plaque vulnerability, as evidenced by the increased collagen fiber, increased expression of α- smooth muscle actin (α-SMA), and decreased Cluster of differentiation 14 (CD14). Additionally, PDS also inhibit the nuclear factor kappa B (NF-κB)-mediated vascular inflammation in the aorta. In conclusion, PDS, but not PTS, might mainly contribute to the anti-atherosclerosis of P. notoginseng.