Evaluation of autoantibodies against oxidized LDL and antioxidant status in top soccer and basketball players after 4 months of competition

Antioxidant status and titers of autoantibodies against oxidized low-density lipoproteins (ox-LDL-Ab) were investigated in top soccer (S; n = 21, age 24.6 +/- 4.3 years) and basketball (B; n = 9, age: 29.8 +/- 5.7 years) players in resting conditions after 4 months of regular training and competition. Plasma antioxidant status (vitamins A, C, E, and selenium) appeared to be normal when compared with a control population of 123 healthly and sedentary individuals. However, some marginal deficiency in vitamins C, E, and proteins sulfhydryl were observed. Moreover, high levels of glutathion peroxidase (GPx) enzyme were detected in 7 out of 30 players (5S and 2B). Despite an apparent normal antioxidant status, elevated levels (> 3,000 mIU/ml) in ox-LDL-Ab were found in half the players (12S and 4B) with a maximum reaching 6000 mIU/ml (normal range: 200-600 mIU/ml), showing an in vivo LDL oxidation. There was no correlation between ox-LDL-Ab titers and chlolesterol, LDL cholesterol, or antioxidant levels. Nevertheless, plasma vitamin C concentration was lower in athletes having high levels of ox-LDL-Ab when compared with those with normal levels (8.49 +/- 3.14 mu g/ml vs. 10.39 +/- 2.55 mu g/ml), but this difference was not statistically significant. In conclusion, our data suggest that potential atherogenic and cardiovascular risks as reflected by high titers in ox-LDL-Ab may exist in some top athletes despite a nonaltered antioxidant status. (C) 2000 Elsevier Science Inc.