Decreased concentrations of the lipoprotein lipase inhibitor angiopoietin-like protein 4 and increased serum triacylglycerol are associated with increased neonatal fat mass in pregnant women with gestational diabetes mellitus

Abstract

Context: Angiopoietin-like protein 4 (ANGPTL4) is an extracellular inhibitor of lipoprotein lipase (LPL) activity. No studies have been done in pregnancy in which hypertriglyceridemia and tissue-specific changes in LPL activity are present.

Objective: The objective of the study was to determine the relationship between neonatal fat mass (FM) and concentrations of ANGPTL4 and triacylglycerols (TAG) in maternal and cord serum of pregnant women with gestational diabetes mellitus (GDM) compared with controls.

Design: Maternal blood samples (control, n = 90, and GDM, n= 80) and umbilical cord blood were drawn before and after vaginal delivery, respectively. Control and GDM subjects were grouped separately into 3 subgroups, according to neonatal FM: 0-25th percentiles, 25th-75th percentiles, and 75th-100th percentiles.

Outcome measures: Glucose, insulin, TAG, nonesterified fatty acids (NEFAs), and ANGPTL4 were determined in maternal and neonatal serum.

Results: Age and pregestational body mass index did not differ between GDM and control women in any subgroups. Maternal serum of GDM pregnant women who delivered the newborn with the highest FM showed the highest concentrations of TAG and NEFAs and lowest concentration of ANGPTL4, despite glucose and insulin concentrations being independent of changes in neonatal FM. However, cord serum of neonates of GDM patients with the highest FM showed higher concentrations of insulin and lower concentrations of TAG than those with lower neonatal FM but no significant differences in NEFAs or ANGPTL4 concentrations.

Conclusions: 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.