Elevated soluble cellular adhesion molecules in subjects with low HDL-cholesterol

The purpose of this study was to investigate whether the expression of cellular adhesion molecules (CAMs) is enhanced in individuals with low HDL cholesterol (HDL-C). Plasma levels of soluble vascular cell adhesion molecule-1 (sVCAM-1), intercellular adhesion molecule-1 (sICAM-1), and E-selectin (sE-selectin) were measured in subjects with low (below the 10th percentile for the Italian population), average, or high (above the 90th percentile) HDL-C. Average sICAM-1 and sE-selectin levels were significantly higher in two groups of 65 individuals with low HDL levels, either hyperlipidemic (320.5±16.0 and 61.4±3.5 ng/mL) or normolipidemic (309.6±13.0 and 60.0±2.7 ng/mL), than in subjects with average HDL levels, either hyperlipidemic (267.0±10.1 and 50.4±2.8 ng/mL) or normolipidemic (257.9±5.4 and 51.1±2.4 ng/mL), or with high HDL levels (254.8±10.2 and 52.5±3.2 ng/mL). No significant difference was found in the plasma sVCAM-1 concentration. HDL-C was inversely correlated with sICAM-1 and sE-selectin in the low-HDL subjects (r2=0.087 and 0.035, P=0.0007 and 0.033, respectively), but not in individuals with normal or elevated HDL-C (r2=0.012 and 0.006). A fenofibrate-induced increase of HDL-C in 20 low-HDL subjects was associated with a significant reduction of plasma sICAM-1 and sE-selectin concentrations. An increased CAMs expression may be a mechanism by which a low plasma HDL level promotes atherogenesis and causes acute atherothrombotic events.