Placental Vesicles Carry Active Endothelial Nitric Oxide Synthase and Their Activity is Reduced in Preeclampsia

Abstract

Supplemental Digital Content is available in the text.

Immunological effects of placental extracellular vesicles

“…These changes are balanced by a reduction in total peripheral resistance, such that by the third trimester, pregnant women have lower blood pressure than nonpregnant women . Exactly what controls these dramatic adaptations is not fully understood, but there is growing evidence that placental EVs are involved …”

“…Placental micro‐EVs have also been reported to inhibit vasodilation of subcutaneous arteries in vitro while in vivo , placental nano‐EVs affected vasodilation of mesenteric arteries in a time‐dependent manner . This may be due to the presence of functional nitric oxide synthase in placental EVs . It is interesting to speculate that the time‐dependent effects of placental EVs on the vasculature may be due to the bioactive proteins delivered by the EVs (immediate effects), while the longer term effects may be due to other molecules present in the EVs (such as miRNA) that can regulate recipient cell gene expression.…”

Extracellular vesicles generated by placental tissues ex vivo: A transport system for immune mediators and growth factors

“…A number of publications have addressed placental EVs and their potential role in pregnancy and its complications . Several ex vivo (eg, placental perfusion) and in vivo systems have been used as a source of EVs. Placental perfusion is a useful method for obtaining large numbers of EVs directly from the placenta; however, this technique is suitable only for a short period of time (2‐6 hours) after delivery .…”

Extracellular vesicles in normal pregnancy and pregnancy‐related diseases

“…The decreased eNOS level is considered to be associated with decreased bioavailability of NO in PE. Motta‐Mejia et al demonstrate that STBEVs isolated from both placenta perfusate and circulating plasma of PE have lower levels of STBEV‐eNOS compared to normal pregnant group. Placental exosomes from PE patients reduce eNOS expression and NO production in HUVECs, which could be attributed to increased expression of miR‐155 in exosomes .…”