The effect of Alcoholic garlic (Allium sativum) extract on ABCA1 expression in human THP-1 macrophages

ATP-binding cassette transporter A1 (ABCA1) is a key mediator of cholesterol efflux to apoA-I in lipid-laden macrophages, the first step of reverse cholesterol transport (RCT) in vivo and a critical step in preventing atherosclerosis. Enhanced ABCA1 expression may inhibit foam cell formation and consequently reduce atherogenic risk. On the other hand, garlic, Allium sativum, and garlic extracts have been demonstrated to have potential cardiovascular benefits. Moreover, garlic has direct antiatherogenic and antiathersclerotic effects on artery walls. The aim of this study was to evaluate the effects of alcoholic garlic extract on the expression of ABCA1 in macrophages.

Cell viability assay was used in order to detect the cytotoxic dose of alcoholic garlic extract on macrophages. Real-time PCR and Western blotting were performed to study the effects of alcoholic garlic extract on the expression of ABCA1. Macrophage cells were treated by different concentrations of alcoholic garlic extract for 48 h. The total RNA of the treated macrophages were extracted and analyzed by real-time PCR. ABCA1 protein expression was also analyzed using the Western blotting technique.

Alcoholic garlic extract increased the ABCA1 mRNA (20-23%) and protein expression (18-37%) in THP-1 macrophage cells compared with the controls (untreated cells).

The results of this study are suggestive of the potential effects of alcoholic garlic extract in increasing ABCA1 expression in macrophages, the possibility of promoting reverse cholesterol efflux in macrophages and preventing atherosclerosis.