Saponins from Allii Macrostemonis Bulbus attenuate atherosclerosis by inhibiting macrophage foam cell formation and inflammation

Allii Macrostemonis Bulbus (AMB) is a traditional Chinese medicine with medicinal and food homology. AMB has various biological activities, including anti-coagulation, lipid-lowering, anti-tumor, and antioxidant effects. Saponins from Allium macrostemonis Bulbus (SAMB), the predominant beneficial compounds, also exhibited lipid-lowering and anti-inflammatory properties. However, the effect of SAMB on atherosclerosis and the underlying mechanisms are still unclear. This study aimed to elucidate the pharmacological impact of SAMB on atherosclerosis. In apolipoprotein E deficiency (ApoE^−/−) mice with high-fat diet feeding, oral SAMB administration significantly attenuated inflammation and atherosclerosis plaque formation. The in vitro experiments demonstrated that SAMB effectively suppressed oxidized-LDL-induced foam cell formation by down-regulating CD36 expression, thereby inhibiting lipid endocytosis in bone marrow-derived macrophages. Additionally, SAMB effectively blocked LPS-induced inflammatory response in bone marrow-derived macrophages potentially through modulating the NF-κB/NLRP3 pathway. In conclusion, SAMB exhibits a potential anti-atherosclerotic effect by inhibiting macrophage foam cell formation and inflammation. These findings provide novel insights into potential preventive and therapeutic strategies for the clinical management of atherosclerosis.