Physical activity blunts oxidative stress response to exercise in sickle cell trait carriers

Abstract

Sickle cell trait (SCT) is characterized by hemorheological and endothelial abnormalities, possibly related to an increase in oxidative stress. Habitual exercise training has been shown to decrease oxidative stress through an up‐regulation of antioxidant defences. The aim of this study is therefore to test if regular physical activity can affect oxidative stress and nitric oxide (NO) metabolism in SCT carriers compared to sedentary counterparts. Plasma levels of 4 oxidative stress markers, antioxidant enzymes activities (SOD and GPX), NO metabolism (NOx) and adhesion molecules were assessed at baseline and following a maximal incremental exercise test (Tex) in 40 trained (T) or sedentary (S) subjects, carriers (SCT) or not (CON) of the sickle cell trait. At Tex, T‐SCT had a lower level of all the oxidative stress markers compared to the 3 others groups. Regardless the disease status (SCT or CON), trained subject had a higher activity of SOD, GPX and NOx at Tex. Finally, the changes in oxidative stress induced by exercise were correlated positively with changes in adhesion molecules and negatively with changes in NOx. Our findings indicate that regular physical training can decrease oxidative stress and improve nitric oxide metabolism and vascular adhesion in response to exercise in sickle cell trait carriers. This is likely explained by the improvement of antioxidant enzymes activities in trained subjects.