Disruption of HDL antioxidant properties in children and adolescents with obesity

Abstract

ObjectiveChildhood obesity is associated with alterations in lipoprotein metabolism and increased oxidative stress, assessed by lipid peroxidation products, reactive oxygen species (ROS) and nitric oxide (NO) levels, oxidized/reduced glutathione (GSH/GSSG) ratio, and the activities of superoxide dismutase (SOD) and catalase. High density lipoproteins (HDL) play an antioxidant role, conditioned by cholesteryl ester transfer protein (CETP), paraoxonase (PON) 1, lecithin:cholesterol acyltransferase (LCAT), lipoprotein-associated phospholipase A2 (Lp-PLA2), and apo A-I. This study aims to evaluate HDL antioxidant capacity in children and adolescents with obesity and the status of its conditioning factors.MethodsThirty children and adolescents, 15 with obesity and 15 normal-weight controls were studied in a cross-sectional observational study. Lipid profile and hs-CRP were assessed using standardized methods. Lipid peroxidation products, ROS, NO, GSH and GSSG levels, and catalase, SOD, CETP, LCAT, PON 1 [PON and arylesterase (ARE)] and Lp-PLA2 activities by developed techniques. Total HDL antioxidant activity and its intrinsic oxidation were evaluated.ResultsChildren with obesity showed lower HDL-C and apo A-I levels (p<0.01), reduced CETP (p<0.05), ARE (p<0.05), LCAT (p<0.05), and HDL-associated Lp-PLA2 (p<0.01) activities, increased HDL intrinsic oxidation (p<0.01) and reduced total HDL antioxidant activity (p<0.05). Patients revealed increased oxidative stress: higher ROS (<0.001) and NO levels (p<0.05), lower GSH/GSSG ratio (<0.01) and catalase activity (p<0.001).ConclusionsChildren and adolescents with obesity exhibited reduced HDL antioxidant activity, alterations in its conditioning factors, intrinsic oxidative modification of HDL particles and increased oxidative stress. These alterations may affect long-term cardiovascular risk in children and adolescents with obesity.