Leukocyte–Endothelium Interaction Is Associated with Fat Mass in Children

Abstract

To study leukocyte-endothelium interaction, a measure of the initial phase of atheromatosis, in children with overweight or obesity. A prospective study was conducted in 77 children aged 7-16years; 47 were children with overweight/obesity and 30 were normal weight. Polymorphonuclear neutrophils (PMNs) and peripheral blood mononuclear cells were isolated from venous blood samples and the interaction of leukocytes over a monolayer of human umbilical vein endothelial cells was analyzed using flow chamber microscopy. The variables studied included leukocyte rolling velocity, rolling flux, and adhesion to endothelial cells. These were compared between children with overweight/obesity and control children. Correlation between the measures of leukocyte-endothelium interaction and anthropometric and biochemical variables was evaluated. In comparison with normal weight children, the PMNs and peripheral blood mononuclear cells of the overweight/obesity group showed a reduction in rolling velocity (P=.000 and P=.001, respectively) and an increase in rolling flux (P=.001 and P=.004), and adhesion (P=.003 and P=.002). The homeostasis model of insulin resistance was correlated inversely with rolling velocity and positively with rolling flux in PMNs. C-reactive protein was correlated positively with rolling flux and adhesion in both types of leucocytes. Fat mass index was correlated with all measures of leukocyte-endothelial interaction and proved to be the main predictor of leukocyte adhesion in the multiple regression analysis (P=.001 for PMNs and P=.006 for peripheral blood mononuclear cells). Excess fat mass in children is related to the activation of the leukocyte-endothelium interaction, potentially contributing to the development of atherosclerosis.