Human ACAT-1 and -2 inhibitory activities of saucerneol B, manassantin A and B isolated from Saururus chinensis

Compounds 1– 3 isolated from the methanolic extracts of Saururus chinensis root inhibited hACAT-1 and hACAT-2 activities. The EtOAc-soluble fraction, which contained compounds 1– 3, of methanol extracts of S. chinensis exhibited strong cholesterol-lowering effect in high cholesterol-fed mice. The sesquineolignan, saucerneol B ( 1), and dineolignans, manassantin A ( 2), and manassantin B ( 3), were isolated from the methanol extracts of Saururus chinensis root and elucidated by their spectroscopic data analysis. Compounds 1– 3 inhibited hACAT-1 and hACAT-2 with IC 50 values of 43.0 and 124.0 μM for 1, of 39.0 and 8.0 μM for 2, of 82.0 μM and only 32% inhibition at 1 mM for 3, respectively. The EtOAc-soluble fraction, which contained compounds 1– 3, of methanol extracts of S. chinensis exhibited strong cholesterol-lowering effect in high cholesterol-fed mice.