Haemoglobin E (HbE), an unstable haemoglobin, is highly susceptible to oxidative damages. We examined how acute or chronic physiological challenge induced by exercise affects antioxidant response in HbE carriers. Two independent studies were conducted in individuals with HbE trait and paired normal Hb. In study 1, sedentary participants were tested in a graded maximal exercise and blood samples were collected before, immediately after, and 45 minutes after an acute exercise. Our data showed that erythrocyte glutathione peroxidase (GPx) activity failed to recover in HbE carriers after 45 minutes of rest. In study 2, athletes were trained in a 10-week strenuous training and blood samples were collected before and after training period. We found that athletes with HbE carriers showed a larger increase in plasma GPx activity compared to those with normal Hb. These data suggest that HbE carriers could cope with exercise-induced oxidative stress by adjusting endogenous antioxidant markers.
Keywords: athletes; glutathione peroxidase; haemoglobinopathy; oxidative stress; training.