Is preeclampsia a syndrome or a disease?
AbstractPreeclampsia (PE) being a rather frequent gestational complication (up to 6% of pregnancies) is always reviewed in connection to high relative risk of maternal mortality and stillbirth. PE influence perinatal morbidity and the risk of postponed maternal morbidity strongly. That is why PE is positioned as the disease, but in fact PE is a syndrome. High-quality obstetric care unit helps to decrease maternal mortality in developed states, though the only way to stop PE and its severe complications is the delivery. Effective preventive strategies are not worked out for PE.
The discovery of changes in micro-RNA at cardiovascular pathology and also at placental dysfunction has led to the search of the newest micro-RNA based diagnostic approach. Learning about pro- and antiangiogenic placental growth factors has also been mooving progressively. The research of biologic patterns and useful specific biological markers for PE and placental dysfunction development stays perspective in basic science.
Aim: 1) to evaluate the role of placental micro-RNA clusters for prognosis of PE; 2) to evaluate the role of pro- and antiangiogenic placental growth factors for prognosis of PE and adverse pregnancy outcomes.
Results. Micro-RNA of cluster miR-675 shows antiproliferative activity; miR-378a-5p and miR-376c enhance trophoblastic proliferation and invasion. МiR-155 inhibits trophoblastic invasion and promotes PE development potentially. МiR-210 and miR-125b-1-3p are involved into suppression of trophoblastic proliferation and invasion, such a way entering their part in placental dysfunction. Micro-RNA of cluster miR-17~92 play a role in oncogenesis.
Placental hypoxia and ischemia stimulate the release of angiogenic factors, which explains the lack of trophoblastic invasion and forming of placental insufficiency. Higher blood pressure levels at early pregnancy and also after PE set off, less gestational age at the delivery (p<0.05), prematurity at earlier gestational age (p<0.05) are shown for the pregnancies complicated with PE and low levels of placental growth factor (PLGF).
Conclusion. Evaluation of micro-RNA levels and pro- and antiangiogenic placental growth factors as biologic markers of PE in peripheral blood is supposed to be useful in future. In spite of large scientific investigation being taken at the moment, useful clinical biomarkers for significant diagnosis of PE are staying unknown. PE is considered to be a syndrome not a disease.
Fundamental science has not finally formed the strict judgment which is the primary and essential reasonable unit among the multiplicity of pathophysiologic changes and which are the secondary units in relation to the primary pathophysiologic changes. A key to PE problem requires future detailed scientific research.
Keywords:preeclampsia, adverse pregnancy outcome, cardiovascular disease, trophoblast, placenta, biomarkers, miRNA, angiogenic factors