Plasma glutathione peroxidase activity negatively correlates with atopic diseases in children but not adults: an exploratory study

Atopic diseases, including atopic dermatitis, food allergy, allergic rhinitis, asthma, and eosinophilic esophagitis (EoE), are characterized by chronic inflammatory responses to aero- and/or food allergens. Oxidative stress has been increasingly implicated in the pathogenesis of these conditions. Antioxidant glutathione peroxidase (GPX) enzymes help mitigate oxidative stress by neutralizing hydrogen peroxide and lipid hydroperoxides. Since EoE requires invasive procedures for diagnosis and surveillance, our primary aim was to determine whether plasma GPX activity levels can be used as a non-invasive biomarker for disease activity, and our secondary aim was to determine whether plasma GPX activity levels correlate with other atopic diseases. While plasma GPX activity levels did not correlate with EoE, they did negatively correlate with non-EoE atopic disease in pediatric, but not adult subjects. These findings necessitate future studies to determine their clinical utility and underlying mechanisms.