Oxidative Stress Effects on Endothelial Cells Treated With Different Athletes' Sera.

PURPOSE.: Exercise training is a non-pharmacological intervention that improves cardiovascular function and enhances endothelial homeostasis in patients with cardiovascular diseases. However, the amount of benefit achieved varies widely depending on the type and duration of exercise. Moreover, data about the long-term effects of physical activity are scarce. METHODS.: In this study, endothelial cells (ECs), exposed or not to oxidative stress, were conditioned with sera from athletes regularly participating in sports classified as "aerobic" (triathlon), "mixed aerobic-anaerobic" (soccer) and "anaerobic" (sprint running). RESULTS.: Functional and hemodynamic variables did not differ between groups of athletes, whereas there were dramatic changes in serum markers for oxidative stress. Lipid peroxidation assessed by thiobarbituric acid reactive substances assay, and catalase activity were lowest and nitric oxide availability highest in sera of triathletes. ECs cultured in serum from triathletes (T-ECs) had the highest survival, evaluated by MTT, BrdU incorporation and SA-βgal associated senescence assays, and preserved the endothelial appearance before and after stress in contrast to the cells grown in sera from the other athletes. T-ECs also had the highest catalase mRNA expression and, after stress, the highest catalase activity of all the ECs. Moreover, post-stress activity of Sirt1, a NAD-dependent deacetylase involved in cellular stress resistance and a key regulator of longevity, was significantly increased in T-ECs. CONCLUSION.: Different types of exercise training induced different molecular effects in terms of survival, morphology and antioxidant system efficiency. The in vitro technique used herein may help to shed light on the molecular basis of effects of long term physical activity in humans.