The effect of alcohol consumption on endothelial adhesion molecule expression

Endothelial adhesion molecules (AM) play an important role in the pathogenesis of several diseases namely infections, neoplasms and chronic inflammatory diseases. Because alcoholic hepatitis and even atherosclerosis are considered as inflammatory diseases and ethanol may modulate inflammatory response, several researchers have investigated the link between ethanol consumption, endothelial AM and the development of both processes. In vitro, animal and human studies have analysed the effects of ethanol and non-alcoholic components of alcoholic beverages on inflammatory biomarkers of atherosclerosis such as monocyte and endothelial AM. These studies have shown that both ethanol and non-alcoholic components of alcoholic beverages, mainly polyphenols, reduce intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and E-selectin expression of vascular endothelium, as well as monocyte adhesion to this endothelium. These data suggest that moderate alcohol intake has an anti-inflammatory effect on the cardiovascular system and reduces early serum markers of atherosclerosis. However, at higher doses ethanol may exert an inflammatory effect. In fact, chronic alcoholics exhibit significantly higher serum levels of endothelial AM than abstainers and moderate drinkers. In addition, an upregulation of E-selectin, ICAM-1 and VCAM-1 is also detected in liver biopsies obtained from patients with alcoholic hepatitis and cirrhosis. The clinical usefulness of the measurement of serum endothelial AM is discussed.