Diabetes mellitus type 2 is a disease associated with an increased release of reactive oxygen species (ROS). Peroxiredoxins are a new group of peroxidases thought to be of great anti-oxidative importance especially in situations of high amounts of free radicals (e.g. inflammation, physical activity). Therefore, we studied the expression (immunohistochemistry) of peroxiredoxins 1 to 6 in red blood cells (RBCs) of non-insulin-dependent (type II) diabetics (n=6, male; age: 6414; BMI: 31.23,3 kg/m²) before and after a three months endurance exercise intervention (2 times a week, 45 minutes at 2 mM lactate). Moreover, the basal expression of peroxiredoxins in RBCs of diabetics was compared to the basal expression in RBCs of non-diabetic men (n=6; age: 577; BMI: 29,44,1 kg/m²). In addition, we measured 8-isoprostan formation in erythrocytes before and after the training intervention.

In red blood cells, we only observed the presence of peroxiredoxin-isoforms 1 and 2. In comparison to non-diabetics the expression of peroxiredoxin 1 was significantly augmented in diabetic men. Endurance training significantly increased the protein expression of peroxiredoxin 1 and 2 in diabetics.

Conclusions: 

Diabetes mellitus type II induces an up-regulation of peroxiredoxin 1 in red blood cells. Physical activity ameliorates the anti-oxidative capacity in red blood cells by the up-regulation of peroxiredoxins 1 and 2. These alterations may effectively counteract the systemic release of ROS in situations of physical exercise.