Christos D. Georgiou

Obesity in children and adolescents has been associated with oxidative stress (OS). The lipid hydroperoxides (LOOH) and the malondialdehyde (MDA) and thiobarbituric reactive substances (TBARS) that oxidatively modify proteins (Pr) (i.e., PrMDA and PrTBARS, respectively) represent markers of OS-associated lipid peroxidation. We aimed to assess OS in children and adolescents with obesity using—for the first time—markers involved in the early and late lipid oxidation process. LOOH, PrMDA, and PrTBARS were investigated in 41 children and adolescents with obesity and 31 controls. Obesity was defined as BMI > 95% for age and sex. The PrMDA/PrTBARS pair, which reflects a late peroxidation stage, was found to be significantly high (39%/180%) in children and adolescents with obesity compared to controls (p < 0.001). Similarly, the early LOOH peroxidation stage marker was increased by 30%. The studied OS parameters were not influenced by sex or age. Our study introduces LOOH, PrTBARS, and PrMDA as markers for evaluating OS in children and adolescents with obesity. LOOH, PrTBARS, and PrMDA may also hold promise as prognostic markers for potential obesity-associated long-term complications.