Impact of physical activity on redox status and nitric oxide bioavailability in nonoverweight and overweight/obese prepubertal children

• Published in: Free radical biology & medicine 2021-02, Vol.163, p.116-124
• Main Authors: Leite-Almeida, Laura, Morato, Manuela, Cosme, Dina, Afonso, Joana, Areias, José C., Guerra, António, Caldas Afonso, Alberto, Albino-Teixeira, António, Sousa, Teresa, Correia-Costa, Liane
• Format: Article
• Language: English
• Subjects: Antioxidant capacity; Cardiometabolic risk factors; Childhood obesity; Exercise; Nitric oxide; Oxidative stress; Physical activity
• ISSN: 0891-5849; 1873-4596
• DOI: 10.1016/j.freeradbiomed.2020.12.005

Nutritional status might contribute to variations induced by physical activity (PA) in redox status biomarkers. We investigated the influence of PA on redox status and nitric oxide (NO) production/metabolism biomarkers in nonoverweight and overweight/obese prepubertal children. We performed a cross-sectional evaluation of 313 children aged 8–9 years (163 nonoverweight, 150 overweight/obese) followed since birth in a cohort study (Generation XXI, Porto, Portugal). Plasma total antioxidant status (P-TAS), plasma and urinary isoprostanes (P-Isop, U-Isop), urinary hydrogen peroxide (U–H2O2), myeloperoxidase (MPO) and plasma and urinary nitrates and nitrites (P-NOx, U-NOx) were assessed, as well as their association with variables of reported PA quantification (categories of PA frequency (>1x/week and ≤1x/week)and continuous PA index (obtained by the sum of points)) in a questionnaire with increasing ranks from sedentary to vigorous activity levels. U-NOx was significantly higher in children who presented higher PA index scores and higher PA frequency. Separately by BMI classes, U-NOx was significantly higher only in nonoverweight children who practiced PA more frequently (p = 0.037). In overweight/obese children, but not in nonoverweight, P-TAS was higher among children with higher PA frequency (p = 0.007). Homeostasis model assessment index (HOMA-IR) was significantly lower in more active overweight/obese children, but no differences were observed in nonoverweight children. In the fully adjusted multivariate linear regression models for P-TAS, in the overweight/obese group, children with higher PA frequency presented higher P-TAS. In the U-NOx models, U-NOx significantly increased with PA index, only in nonoverweight children. Our results provide additional evidence in support of a protective effect of physical activity, in nonoverweight by increasing NO bioavailability and in overweight/obese children by enhancing systemic antioxidant capacity and insulin sensitivity. These results highlight the importance of engaging in regular physical exercise, particularly among overweight/obese children, in which a positive association between oxidant status and cardiometabolic risk markers has been described. [Display omitted] •Exercise improves NO bioavailability in nonoverweight children.•Exercise improves antioxidant capacity in overweight/obese children.•Exercise improves insulin sensitivity in overweight/obese children.