Impaired insulin-mediated glucose uptake in monocytes of short children with intrauterine growth retardation.

Abstract

To determine whether there was an impairment in insulin-mediated glucose uptake in monocytes from short children with intrauterine growth retardation (IUGR) when compared with control subjects. Circulating monocytes were isolated by histopaque gradient separation followed by adherence. Monocytes were incubated with insulin at the following concentrations; 0, 0.1, 0.2, 0.6, 1, 2 and 6 nm. 2-deoxyglucose (2-DG) uptake was measured after incubation with [(3)H]2-DG and expressed as pmol/min/10(6) cells. Insulin-stimulated glucose uptake was determined in two ways: 6 nm insulin concentration minus baseline (6-0 nm) and the regression slope of glucose uptake over the range of log insulin concentrations (slope value). Insulin sensitivity was determined from a 90-min frequently sampled intravenous glucose tolerance test with the minimal model. Short children with IUGR (n = 16) had lower slope (4.6 +/- 1.1 vs. 9.5 +/- 2.0, p = 0.002) and 6-0 nm (8 +/- 2 vs. 15 +/- 3 pmol/min/10(6) cells, p = 0.048) glucose uptake values than normal children (n = 11). There was no difference in baseline glucose uptake between IUGR and normal children (36 +/- 5 vs. 48 +/- 7 pmol/min/10(6) cells). In the five subjects with IUGR that were evaluated, the in vivo insulin sensitivity index and glucose effectiveness were found to be positively correlated with insulin-mediated glucose uptake in monocytes (r = 0.54) and baseline glucose uptake in monocytes, respectively (r = 0.69). Short children with IUGR have impairment in insulin-mediated glucose uptake in monocytes when compared with normal children. Our hitherto limited data indicate that insulin-mediated glucose uptake in monocytes is correlated with in vivo assessment of insulin sensitivity in children with IUGR.