Acyl-coenzyme A: cholesterol acyltransferase (ACAT) esterifies free cholesterol in the liver and the intestine. It has relations with production of lipoproteins and accumulation of cholesteryl esters of the atheroma. Therefore, ACAT inhibitors may act as antihypercholesterolemic and antiatherosclerotic agents.
View Article and Find Full Text PDFIn the search for cell adhesion inhibitors from natural sources, three active compounds were isolated from Chloranthus japonicus Sieb. (Chloranthaceae) roots. The compounds were identified as dimeric sesquiterpenoids of shizukaol B (1), cycloshizukaol A (2) and shizukaol F (3).
View Article and Find Full Text PDFLeukocyte adhesion to the vascular endothelium is a critical initiating step in inflammation and atherosclerosis. We have herein studied the effect of manassantin A (1) and B (2), dineolignans, on interaction of THP-1 monocytic cells and human umbilical vein endothelial cells (HUVEC) and expression of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin in HUVEC. When HUVEC were pretreated with 1 and 2 followed by stimulation with TNF-alpha, adhesion of THP-1 cells to HUVEC decreased in dose-dependent manner with IC50 values of 5 ng/mL and 7 ng/mL, respectively, without cytotoxicity.
View Article and Find Full Text PDFThe accumulation of circulating monocytes in the arterial wall is an early in atherosclerotic plaque formation. Monocyte chemoattractant protein-1 (MCP-1) promotes the migration of monocytes and would play a role in the development of atherosclerotic lesions. Searching for inhibitors of MCP-1-induced cell migration from natural sources, we isolated one active compound through active-guided fractionations from the MeOH extracts of Sophora flavescens Ait (Leguminosae).
View Article and Find Full Text PDFJ Agric Food Chem
February 2005
Acyl-CoA: cholesterol acyltransferase (ACAT), which plays a role in the absorption, storage, and production of cholesterol, has been explored as a potential target for pharmacological intervention of hyperlipidemia and atherosclerotic disease. In our search for ACAT inhibitors from natural sources, the petroleum ether extract of Panax ginseng showed moderate inhibition of ACAT enzyme from rat liver microsomes. Bioactivity-guided fractionations led to the isolation of one new polyacetylenic compound, (9R,10S)-epoxy-16-heptadecene-4, 6-diyne-3-one (1), in addition to the previously reported polyacetylenic compounds 2 and 3.
View Article and Find Full Text PDFBioactivity-guided fractionations for ACAT inhibitor led to the isolation of guineensine from the CHCl (3) extract of Piper longum. Its structure was identified by spectroscopic means (IR, UV, MS and NMR). Guineensine inhibited ACAT activity in a dose-dependent manner with an IC (50) value of 3.
View Article and Find Full Text PDFCell adhesion inhibitors were isolated from the methanol extract of Saururus chinensis roots by bioactivity-guided fractionation. The active compounds were identified as manassantin A ( 1) and B ( 2), dineolignan compounds. Compounds 1 and 2 inhibited PMA-induced ICAM-1/LFA-1-mediated homotypic aggregation of the HL-60 cells without cytotoxicity with MIC values of 1.
View Article and Find Full Text PDFIn the course of our search for Acyl-CoA: cholesterol acyltransferase (ACAT) inhibitors from natural sources, a new type of ACAT inhibitor was isolated from a methanol extract of Diospyros kaki. On the basis of spectral and structural evidence, the compound was identified as pheophorbide A-methyl ester. Pheophorbide A-methyl ester inhibited ACAT activity in a dose dependent manner with an IC50 value of 1.
View Article and Find Full Text PDFIn the course of our search for Acyl-CoA:cholesterol acyltransferase (ACAT) inhibitors from natural sources, a new type of ACAT inhibitor was isolated from the methanol extract of Persicaria vulgaris. On the basis of spectral evidence, the structure of the active compound was identified as pheophorbide A. Pheophorbide A inhibited ACAT activity with an IC 50 value of 1.
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