Regulatory effect of miR-195 in the placental dysfunction of preeclampsia.

Preeclampsia (PE) is a pregnancy specific disease soon after 20 weeks of gestation where major symptoms are hypertension and proteinuria. The underlying pathology is believed to be abnormal placentation. Epigenetic and genetic factors have significant roles in abnormal placental development. MicroRNA's (miRNAs), being one of the most important epigenetic regulators, take part in abnormal placentation. Hsa-miR-195 is a molecule associated with abnormal placental growth mechanisms such as impaired cellular proliferation, inadequate trophoblastic invasion causing defective spiral artery remodeling, and apoptosis. We aimed to evaluate miRNA functions, namely miR-195 expression profile, in order to divulge PE pathogenesis. In this study, we extracted circulating miRNAs from maternal plasma and placenta from 20 PE patients and 20 normotensive pregnant women. miR-195 was quantified using quantitative real time reverse transcriptase PCR (qRT-PCR). The target genes of miR-195 were predicted by Diana Tools-mirPath, TargetScan, and miRDB databases. We found that miR-195 levels were downregulated (3.83-fold decrease,  < .05) in preeclamptic placenta samples, however miR-195 were undetected in preeclamptic and normotensive plasma samples. The steep down-regulation of miR-195 points to its importance of PE pathogenesis. miR-195 is suggested to regulate PE its target genes manipulating biological processes such as placental proliferation, apoptosis, and angiogenesis. We propose that detection of decreased miR-195 levels in preeclamptic placentas could be used to enlighten the pathophysiology of PE.