Upregulation of enzymatic antioxidants in CD4+ T cells of autistic children

Abstract

Autism spectrum disorder (ASD) is a neurodevelopmental disorder which begins in early childhood and presents itself with characteristic symptoms such as repetitive behavioral patterns and problems in speech/social interactions. Adaptive immune system is thought to be involved in the etiology of ASD. T cells orchestrate amplification of inflammation through release of inflammatory mediators; however, antioxidant defenses have not been evaluated in CD4+ T cells of ASD subjects. In this study we evaluated intracellular enzymatic antioxidant potential through measurement of major antioxidant enzymes (SOD, GPx, and GR) in ASD subjects and typically developing control (TDC) children and further assessed its role in modulation of inflammation. Our data reveal that there is an increase in antioxidant potential (SOD, GPx, GR) in CD4+ T cells of ASD subjects as compared to TDC children at both protein and activity level. Further, this antioxidant increase was associated with upregulated IL-17A levels in CD4+ T cells. This was corroborated by oxidant treatment in vitro. Pretreatment with oxidant, H2O2 led to attenuation of IL-17A levels along with increased oxidative stress in stimulated CD4+ T cells from ASD subjects. These data reveal that antioxidant play an essential role in modulation of inflammatory potential in CD4+ T cells of ASD subjects.