Poster Presentation Australasian Diabetes in Pregnancy Society Annual Scientific Meeting 2016

Exosomal profile present in maternal and foetal circulation during pregnancies with diabetes (#118)

Stefanie Adam 1 , Katherin Scholz-Romero 1 , Gregory E Rice 1 , Martha Lappas 2 , Carlos Salomon 1 3
  1. Exosome Biology Laboratory, Centre for Clinical Diagnostics (CCD), University of Queensland Centre for Clinical Research (UQCCR), Herston, QLD, Australia
  2. Obstetrics, Nutrition and Endocrinology Group, Department of Obstetrics and Gynaecology, University of Melbourne, Melbourne, Victoria, Australia
  3. Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Ochsner Clinic Foundation, New Orleans, Louisiana, USA

Background: Diabetes during pregnancy is associated with risks to women and foetus such as miscarriage, preeclampsia and preterm birth. In recent years, we have established that exosomes increase during normal gestation where their release from placental cells increase in response to glucose concentration. The aim of this study was to determine the concentration of exoomes present in maternal and foetal circulation in women with with pre-gestational diabetes (Type 1 and 2) and gestational diabetes (treated with diet or insulin).

Methods: Plasma was obtained from maternal and cord blood from women with diabetes type 1 (DM1), type 2 (DM2) and gestational diabetes treated with diet (GDM-diet) or insulin (GDM-insulin) at time of delivery. Exosomes were isolated through differential and buoyant density centrifugation and characterised by size distribution, enrichment of TSG101 and morphology using NanoSight, Western Blot and electron microscopy, respectively. Total number of exosomes (EXO) present in maternal and foetal circulation was determined by nanoparticle tracking analysis and presented as vesicles per mL plasma.

Results: Exosomes were identified as spherical vesicles with size distribution ~100 nm and positive for the enriched exosomal marker TSG101. EXO was significantly higher in diabetic pregnancies compared to normal (p<0.05) in both maternal and foetal plasma. Interestingly, EXO was significantly higher in foetal plasma compared to maternal plasma matched by conditions (normal 1.16x109 vs 1.62x109, GDM-diet 1.7x109 vs 2.64x109, GDM-insulin 1.8x109 vs 2.60x108, DT1 9.6x108 vs 2.78x109 and DT2 1.7x109 vs 2.69x109, for maternal and foetal, respectively). EXO in foetal plasma was correlated with glucose levels after OGTT at 2h and EXO in maternal plasma was correlated with birth weight in normal and DT1 pregnancies.

Conclusions: The data obtained in this study was the first to characterise changes in maternal and fetal plasma exosomes in diabetic pregnancies. As such, it may provide a baseline that will facilitate the understanding on the role of exosomes during gestation.