Background: Inflammation has been postulated to play an important role in atherosclerosis development. Recently, research in this field has been focused on the role of modified lipoproteins, primarily oxidized low density lipoprotein. Adhesion and transendothelial migration of circulating leukocytes, by the action of cell-adhesion molecules, seem to be critical steps in early atherogenesis. Previous in vitro studies on the relationship between ox-LDL and the expression of cell-adhesion molecules on endothelial cells have shown diverging results. Furthermore, there are as yet no reports on the relationship between circulating ox-LDL and cell-adhesion molecules in vivo.
Material/methods: The relationship between circulating ox-LDL and adhesion molecules was measured by ELISA in clinically healthy, 58-year-old men recruited from the general population (n=391).
Results: The results of the present study showed that circulating ox-LDL was associated with sICAM-1 and sE-selectin, but not with sVCAM-1. After adjustment for other risk factors, i.e. systolic blood pressure, LDL cholesterol, apoB, apoA1 and smoking, the observed relationships between ox-LDL and sICAM-1 and sE-selectin, respectively, remained statistically significant.
Conclusions: The observed results fit into the concept that oxidatively modified LDL may regulate the increased expression of cell-adhesion molecules on endothelial cells in vivo. These observations were made in a population-based sample of clinically healthy, middle-aged Caucasian men. Since this was a cross-sectional study no conclusions can be drawn on causality.