Better knowledge on the disturbed mechanisms implicated in materno-fetal long-chain polyunsaturated fatty acid (LC-PUFA) transfer in pregnancies with gestational diabetes mellitus (GDM) may have potentially high implications for later on in effective LC-PUFA supplementation. We studied in vivo placental transfer of fatty acids (FA) using stable isotope tracers administrated to 11 control and 9 GDM pregnant women (6 treated with insulin). Subjects received orally [13C]palmitic, [13C]oleic and [13C]linoleic acids, and [13C]docosahexaenoic acid (13C-DHA) 12 h before elective caesarean section. Maternal blood samples were collected at −12, −3, −2, and −1 h, delivery, and +1 h. Placental tissue and venous cord blood were also collected. FA were quantified by gas chromatography (GC) and 13C enrichments by GC-isotope ratio mass spectrometry. [13C]FA concentration was higher in total lipids of maternal plasma in GDM vs. controls, except for [13C]DHA. Moreover, [13C]DHA showed lower placenta/maternal plasma ratio in GDM vs. controls and significantly lower cord/maternal plasma ratio. For the other studied FA, ratios were not different between GDM and controls. Disturbed [13C]DHA placental uptake occurs in both GDM treated with diet or insulin, whereas the last ones also have lower [13C]DHA in venous cord. The tracer study pointed toward impaired placental DHA uptake as critical step, whereas the transfer of the rest of [13C]FA was less affected. GDM under insulin treatment could also have higher fetal fat storage, contributing to reduce [13C]DHA in venous cord. DHA transfer to the fetus was reduced in GDM pregnancies compared with controls, which might affect the programming of neurodevelopment in their neonates.
Docosahexaenoic Acid (DHA) Supplementation Benefits Pregnancy Complicated with Gestational Diabetes Mellitus (GDM)