Triterpenoid-enriched extract of Ilex kudingcha inhibits aggregated LDL-induced lipid deposition in macrophages by downregulating low density lipoprotein receptor-related protein 1 (LRP1)

Macrophage-derived foam cell formation is considered to be a critical step in the development of atherosclerosis. In the present study, we evaluated the inhibitory effect of Ilex kudingcha triterpenoid-enriched extract (TS) on foam cell formation in THP-1 macrophage cells induced by aggregated low density lipoproteins (agLDL). The inhibition of low density lipoprotein receptor-related protein 1 (LRP1) expression after TS treatment is based on mRNA and protein levels in the macrophages. These inductions were sterol regulatory element-binding protein-2 (SREBP2) dependent. On the basis of the in vitro results, the anti-atherosclerotic activity of TS was investigated in ApoE−/− mice fed a high-fat diet, ApoE−/− mice treated with TS for 6 weeks appeared to have decreased aortic sinus lesions compared with the untreated mice. These findings indicate that TS may act as an anti-atherosclerotic agent.