The metabolism of erythrocytes is mainly dependent on the uptake of lactate by the monocarboxylate transporter isoform 1 (MCT1). The present study investigates the influence of a three-month strength training (2x2hrs/week) on protein expression and translocation of the MCT1 and its chaperone CD147 (immunhistochemistry, FACS, immunfluorescence by confocal microscopy) as well as on lactate uptake in erythrocytes of men suffering from non-insulin dependent type 2 diabetes (n=11). Before and after the training period, a WHO-bicycle ergometer testing was performed and blood samples were obtained directly before and 10 min after a WHO-ergometer testing for immunohistochemical erythrocyte analysis. Erythrocyte lactate uptake was determined before, directly after as well as 5 and 10 minutes after the WHO-test.

After three months training intervention, basal erythrocyte lactate concentration of the participants was not altered, erythrocyte lactate concentration was significantly decreased at the maximal cycling power but increased 10 minutes after the WHO-test. Before the training intervention, cytosolic MCT1 distribution did not alter during the ergometer testing; the membraneous CD147 density decreased. MCT1 expression increased and CD147 expression decreased in the erythrocytes after the three month strength training intervention, whereas CD147-density remained unchanged and MCT1-distribution was shifted from the centre to the periphery of the erythrocytes.

Conclusions: 

These strength-training induced alterations of erythrocyte MCT1-expression and location which are paralleled by an increased erythrocyte lactate uptake during regeneration may contribute to an improvement of exercise tolerance in non-insulin-dependent diabetics.