Abstract

Anacardium occidentale belongs to the Anacardiaceae family. It had been scientifically proven to have antihypercholesterolemia effect in high cholesterol diet induced animal laboratory study. However there is no study regarding the mechanisms involves in cholesterol reducing effect by A. occidentale leaves extract. In this study, cytotoxic assessment and anti-cholesterol activity of A. occidentale leaves aqueous extract (AOE) were investigated. Cytotoxic study was performed by exposing hepatoma cell (Hep G2) towards AOE with concentration ranging from 0.002 to 20mg/mL for 24 h. Anacardium occidentale extract was found to be not toxic to the cell. Then, the highest and not toxic AOE concentrations (20, 10, 5 and 2.5 mg/mL) were selected for anti-cholesterol study. The ability of AOE to reducecholesterol in cell culture experiment was carried out by pretreating Hep G2 with selected concentrations of AOE in 6-well plate before the cell was exposed to low density lipoprotein (LDL). The concentration of farnesyl-diphosphate farnesyltransferase (FDFT1), apolipoprotein A1 (Apo A1), lecithin-cholesterol acyltransferase (LCAT), low density lipoprotein receptor (LDL R), scavenger receptor B1 (SR-B1), ATP binding cassette transporter A1 (ABCA-1) and hepatic lipase (HL) were determined from the 6-well plate media. The results showed that AOE did not significantly increase the concentration of LDLR. However, AOE significantly increased the concentration of FDFT1, APO A1, LCAT, SRB-1, ABCA- 1 and HL. The HMGR activity experiment showed that all selected AOE concentrations cannot significantly reduce the HMGR enzyme activity. These findings suggested that AOE may involve in reverse cholesterol transport process to reduce cholesterol metabolism in Hep G2 cell.