NOX2-Driven Oxidative Stress and Endothelial Dysfunction in Male Elite Adolescent Soccer Players.

BACKGROUND

Intense physical exercise induces oxidative stress and inflammation in adult professional athletes, but data on adolescent elite athletes remain limited.

METHODS

Twenty-four elite adolescent soccer players were recruited and evaluated three times: pre-season baseline (T0), after one month of pre-season training (T1), and at the end of the first half of the competitive season (T2, approximately 4 months after T0). Saliva samples were collected as non-invasive surrogate indicators reflecting oxidative stress- and endothelial-related signaling. In vitro studies were performed on endothelial cells exposed to H2O2 concentrations observed in athletes.

RESULTS

Athletes showed a significant increase in salivary oxidative stress markers (NOX2 levels and H2O2) at T1 and T2 versus T0. Endothelial impairment was evidenced by reduced salivary NOx concentration and elevated endothelin (ET-1) levels. In vitro, endothelial cells exposed to H2O2 (8 μM) showed increased sNOX2-dp and ET-1 levels, reduced eNOS phosphorylation, and impaired tube formation (mesh number and area) compared with untreated cells. NOX2ds-tat treatment reduced cell damage and restored angiogenic capacity.

CONCLUSIONS

Our findings indicate that adolescent elite athletes experience significant salivary oxidative stress- and endothelial-related alterations, potentially reflecting cardiovascular stress. These results underscore the importance of cardiovascular monitoring and the potential benefits of antioxidant strategies, even in young athletes participating in high-intensity sports.