Raised concentrations of lipid peroxidation products (LPO) in pregnant women with impaired glucose tolerance.

INTRODUCTION Lipid peroxidation (LPO) results from oxidative damage to membrane lipids. Whereas LPO rises in normal pregnancy, the effect of gestational diabetes mellitus (GDM) on this process has not been clearly defined. MATERIALS AND METHOD Fasting blood concentrations of malondialdehyde+4-hydroxyalkenals (MDA+4-HDA), as LPO index, TNFa soluble receptors (sTNF-R1 and sTNF-R2), and soluble adhesion molecules (sICAM-1, sVCAM-1), were measured in 51 women at 28 weeks of gestation. The women were divided according to the results of 50.0 g glucose challenge test (GCT) and 75.0 g oral glucose tolerance test (OGTT): Controls (n=20), normal responses to both GCT and OGTT; Intermediate Group (IG) (n=15), abnormal GCT but normal OGTT; GDM group (n=16), abnormal both GCT and OGTT. RESULTS Glucose concentrations in women diagnosed with GDM were within the range of impaired glucose tolerance. There were no significant differences in concentrations of either TNF a soluble receptors R1 and R2, or sICAM-1 or sVCAM-1. LPO concentrations [MDA+4-HDA (nmol/mg protein)] were significantly higher in women with GDM than in the other two groups [64.1±24.3 (mean±SD), 39.3±23.1, 47.0±18.1, for GDM, IG and Controls, respectively; p<0.05]. In multivariate analysis, the only significant independent correlation was between LPO level and glucose at 120 minutes of OGTT (rs=0.42; p=0.009). CONCLUSIONS Oxidative damage to membrane lipids is increased in GDM and might result directly from hyperglycaemia. Physiological significance of this phenomenon remains to be elucidated.