Protein oxidation in obesity and insulin resistance

Advanced oxidation protein products (AOPP) are considered reliable markers to estimate the degree of oxidant-mediated protein damage. Data on oxidative stress in childhood obesity and insulin resistance are limited.The aim of this study was to investigate the AOPP level as an oxidative stress marker in obesity and insulin resistance. The study included 57 pubertal obese children and adolescents (30 girls and 27 boys) and 20 healthy pubertal children and adolescents (11 girls and 9 boys).All participants in the obesity group underwent an oral glucose tolerance test (OGTT) and two separate groups were formed according to the existence of insulin resistance.AOPP levels were measured in the obesity and control groups spectrophotometrically. The obesity group consisted of 25 children and adolescents with insulin resistance and 32 subjects without insulin resistance. AOPP levels in the obesity group were found to be significantly higher than those in the control group. Although AOPP levels in the subjects with insulin resistance were higher than the subjects without insulin resistance, there was no significant difference between AOPP levels of subgroups with insulin resistance and without insulin resistance.This study showed protein oxidation in obesity with a novel oxidative stress marker and it also suggests that insulin resistance may play an important role as a source of oxidative stress in the development of other diseases after pubertal years.