EDN1 and preeclampsia: There is an increase in the peripheral blood concentrations of leptin, plasminogen activator inhibitor-1 (PAI-1), sFlt-1 to PlGF ratio, TNF-α, and TNF receptors in patients with preeclampsia, and also increased levels of anti-angiogenic factors, such as sFLT1, sEndoglin, endothelin 1, and leptin in the amniotic fluid of women with preeclampsia (Fig. 3).