The Levels of Soluble Adhesion Molecules in Diabetic and Nondiabetic Patients with Combined Hyperlipoproteinemia and the Effect of Ciprofibrate Therapy

Abstract

Cell adhesion molecules are thought to play a role in atherosclerosis. Several clinical trials have shown that fibrate treatment leads to a reduction in coronary events, although the mechanisms are not fully understood. Soluble vascular cell adhesion molecule-1 (sVCAM-1), soluble intercellular adhesion molecule-1 (sICAM-1) and soluble E-selectin plasma concentrations were measured in 10 obese dyslipidemic men (group A), in 10 obese dyslipidemic type 2 diabetic men without coronary artery disease (CAD) (group B), and in 10 dyslipidemic type 2 diabetic men with angiographically documented CAD (group C) before and after 12 weeks of treatment with ciprofibrate. Compared with nondiabetic dyslipidemic men, diabetic patients with CAD or without documented CAD had significantly increased levels of sVCAM-1 (512 ±39 versus 750 ±139 ng/mL; p<0.0001 and 566 ±78 ng/mL; p<0.01, respectively) and sE-selectin (54.8 ±6.9 versus 65.9 ±8.8 ng/mL; p<0.001 and 62.6 ±9.4 ng/mL; p=0.056, respectively). The levels of sICAM-1 were similar in all 3 groups. Multivariate analyses showed that the higher sCAM levels in patients occurred independently of lipoprotein levels. Waist circumference as a marker of abdominal adiposity was the only independent predictor of elevated concentrations of all 3 cell adhesion molecules in multivariate analyses. sE-selectin was associated with HbA₁C levels (p<0.01) in diabetic men at baseline. After 12 weeks of ciprofibrate therapy, sVCAM-1 levels were reduced by 13.5 ±2.1%, sICAM-1 levels by 11.8 ±2.2%, and sE-selectin levels by 17.1 ±3.5% (p<0.01 for all) with the greatest sE-selectin reduction in the diabetic subgroups (p<0.001). There was no correlation between the lowering of soluble adhesion molecules and the magnitude of lipid-lowering effect. An increased level of circulating adhesion molecules may be a mechanism by which dyslipidemia and/or diabetes mellitus promotes atherogenesis, and treatment with ciprofibrate may alter vascular cell activation.