Effects of Moderate Ethanol Consumption on Lipid Metabolism and Inflammation through Regulation of Gene Expression in Rats

Abstract

Evidence supports a J or U‐shaped correlation with consumption of alcohol and cardiovascular disease (CVD) risk and suggests that light to moderate drinking as opposed to excessive consumption may provide some cardiovascular benefits. The present study examined the underlying mechanisms of how moderate alcohol consumption provides a protective effect against cardiovascular disease. Twenty‐four 109 day old, male Wistar rats were divided into a control group and a treatment group (n=12/group). The treatment group was administered a 20% v/v ethanol solution on alternate days for 12 weeks. There was no difference in body weight gain between the two groups, however, epididymal fat weight was lower in ethanol‐fed rats (P=0.030). Blood glucose was lower in the ethanol group compared to control (P=0.030). Total cholesterol levels (P=0.036) and LDL‐cholesterol levels (P=0.031) were also lower in the ethanol group. There was a significant reduction seen in the expression of hydroxymethylglutaryl‐coenzyme A reductase (Hmgcr) and sterol regulatory element‐binding protein‐2 (Srebp‐2) in the ethanol group (P=0.026 and P=0.034, respectively), suggesting that ethanol lowers cholesterol levels via downregulation of genes involved in cholesterol synthesis. Paraoxonase‐1 (Pon‐1), which is associated with inhibition of LDL‐cholesterol oxidation, was upregulated in the ethanol group (P=0.029). Cyclooxygenase‐2 (Cox‐2) and nuclear factor NF‐kappa‐B p65 subunit (Rela) gene expression was significantly decreased in ethanol‐treated rats (P=0.016 and P=0.047, respectively), indicating possible anti‐inflammatory effects. These findings suggest that moderate ethanol consumption may reduce the risk of CVD by reducing body fat, improving blood cholesterol and blood glucose, and modulation of gene expression involved in inflammation.Support or Funding InformationThis study was funded by NIH AA02329 and supported by San Diego State University N302L Advanced Nutrition Laboratory.