In normal pregnancies, in contrast to those with gestational diabetes, maternal lipids do not influence neonatal weight. Similar levels of maternal lipids in pregnancies with gestational diabetes and control pregnancies, but higher free fatty acids in the cord blood of those with gestational diabetes, indicate their enhanced placental transport and/or enhanced lipolysis as a result of decreased fetal insulin responsiveness.

OBJECTIVETo determine the concentrations of adipocyte fatty acid–binding protein (AFABP) and other adipocytokines in maternal and cord serum of pregnant women with gestational diabetes mellitus (GDM) and of control subjects and to relate them to indexes of insulin sensitivity.RESEARCH DESIGN AND METHODSIn 86 control and 98 GDM pregnant women, venous blood was collected before vaginal delivery and arterial blood from cord immediately after delivery. Serum insulin and adipocytokines were measured by enzyme-linked immunosorbent assay (ELISA).RESULTSGDM women had higher prepregnancy BMI, and data were adjusted for it. Maternal serum insulin, insulin-to-glucose ratio, homeostasis model assessment (HOMA), AFABP, and retinol-binding protein 4 (RBP4) were higher and adiponectin was lower in GDM than in control subjects, whereas serum glucose, insulin, insulin-to-glucose ratio, HOMA, nonesterified fatty acids, and RBP4 were higher and glycerol, AFABP, and adiponectin were lower in cord blood serum of GDM than of control subjects. AFABP and adiponectin in cord serum of control subjects were higher than in maternal serum; in GDM women no difference was found for AFABP in cord versus maternal serum, although adiponectin remained higher in cord. Values of leptin in both groups were lower in cord than in maternal serum, and those of RBP4 were lower in only GDM women.CONCLUSIONSIt is suggested that fetal tissues are the main source of cord arterial serum AFABP, and in GDM fetuses AFABP values correlate with adiposity markers. A downregulation of adiponectin and upregulation of RBP4 in GDM mothers and their fetuses may be related to their insulin-resistant condition, whereas changes in AFABP do not seem to be related.

In well-controlled GDM pregnancies, decreased maternal ANGPTL4 concentrations and a gradient of TAG toward the fetus are related with higher neonatal FM. However, in GDM fetuses with the highest FM, the potential effect of ANGPTL4 inhibiting adipose tissue LPL activity could be overcome by their hyperinsulinemia.

BackgroundLigands of peroxisome-proliferator activated receptors (PPARs), such as non-esterified fatty acids (NEFAs), induce expression of angiopoietin-like protein 4 (ANGPTL4). Recently ANGPTL4 has been reported to be a mediator of intracellular adipose lipolysis induced by glucocorticoids.ObjectiveTo determine the concentrations of ANGPTL4 in cord serum of neonates born by spontaneous vaginal delivery (SVD) and by pre-labor cesarean section (CS) from healthy women, and to relate them to parameters of neonatal lipolytic activity at birth.MeasurementsIn 54 neonates born by SVD and in 56 neonates born by CS, arterial cord blood was drawn to determine insulin, cortisol, triacylglycerols (TAGs), glycerol, non-esterified fatty acids (NEFAs), individual fatty acids, ANGPTL4, adiponectin, retinol binding protein 4 (RBP4) and leptin.ResultsBirth weight and neonatal fat mass in SVD and CS showed no difference, but the concentrations of glycerol, adiponectin, RBP4, NEFAs and most individual fatty acids were higher in cord serum of neonates born by SVD compared to CS, indicating a higher adipose tissue breakdown in the SVD group. The concentrations of TAG and cortisol were also higher and that of insulin was lower in cord serum of SVD compared to the CS group. However, the concentration in cord serum of ANGPTL4 did not differ between the two groups and no positive correlation with either NEFA or glycerol concentrations were detected.ConclusionANGPTL4 is known to stimulate lipolysis in adults, but does not appear to mediate the increased activity in SVD, indicating the presence of different regulatory inputs.