Delayed activation of D-glucose transport in type II diabetes mellitus

Peripheral insulin resistance is suggested to play an important role in the pathogenesis of type II diabetes mellitus. In this study we investigated insulin receptor binding, D-glucose transport under equilibrium conditions for insulin and the activation kinetics of insulin stimulated D-glucose transport in isolated human adipocytes from type II diabetics and healthy controls. While the insulin receptor binding affinity was not significantly different between both groups, basal and insulin stimulated glucose transport rates were reduced in adipocytes from type II diabetics compared to normal controls. The activation of D-glucose transport was significantly delayed in the diabetics, the time to achieve maximal transport rates was 7.7 +/- 1.1 vs. 4.2 +/- 1.4 min, respectively (p < 0.05). Thus a reduced velocity of glucose transport activation by insulin appears to be a further factor contributing to peripheral insulin resistance in type II diabetics.