Extracellular vesicles (EVs) have important roles in pregnancy development and vascular homeostasis. It is proposed that excess glucose levels can change the biochemical composition of placental derived EVs. Here, we investigated the proteomic profile and endothelial vascular actions of small placental EVs, following high glucose exposure.
Healthy placental human tissue was collected at term caesarean section (n=5). Placental explant tissue was cultured for 48 hours under high-glucose or control conditions. EVs were isolated from explant media by ultracentrifugation. Protein was isolated from EVs and assessed by Liquid Chromatography-Mass Spectrometry. Human umbilical vein endothelial cells (HUVECs, n=6) were treated with EVs from either control or high-glucose culture conditions and endothelial activation was assessed (qPCR, ELISA, Western Blot, and leukocyte adhesion assay). Wire myography assessed human omental artery response, following incubation with control or high-glucose placental EVs (n=5).
5,167 proteins were identified in placental EVs; 57 proteins were uniquely expressed in high-glucose conditions. The most abundant proteins identified were associated with cell adhesion, ubiquitination, angiogenesis, cellular repair, growth, and survival. Treatment of HUVECs with placental EVs significantly upregulated markers of endothelial dysfunction (VCAM, ICAM), pro-inflammation (CCL2, CCL7, CX3CL1), and oxidative stress (NOS3); and downregulated CXCL8 (inflammatory cytokine). No difference in expression or leukocyte adhesion between high-glucose and control conditions were observed.
The proteome of EVs was altered in placenta exposed to high-glucose. Placental EVs drove vascular dysfunction and inflammation. These data hold significant potential to inform how high placental glucose availability can change bioactive compounds in EVs and their actions on vasculature.