The long non-coding RPPH1 is decreased in leukocytes and increased in plasma from women developing pre-eclampsia

Abstract

Previous studies show differentially expressed long non-coding RNA present in the placenta from women with pre-eclampsia, potentially playing a vital role in the pathogenesis of the complication. In a published microarray study, Ribonuclease P RNA Component H1 (RPPH1), was decreased in leukocytes from women that later developed pre-eclampsia. We hypothesized that RPPH1 decreased during pregnancy in women developing pre-eclampsia and important for the development of the complication. We isolated RNA from extracellular vesicles, leukocytes and plasma using blood samples taken at week 22-24 and 36-38 in women who subsequently developed pre-eclampsia and from healthy pregnancy. The expression of RPPH1 was quantified using qPCR. Expression of RPPH1 at 22-24 week was further examined to investigate its discriminatory potential of subsequent pre-eclampsia and association with clinical markers. We found lower expression of RPPH1 in leukocytes at 22-24 and 36-38 weeks amongst women who subsequent developed pre-eclampsia compared to those who did not, while increased RPPH1 expression was found in plasma at 36-38 weeks. Pre-eclampsia risk factors could not account for this difference in the RPPH1 expression. Prediction of pre-eclampsia at 22-24 weeks using RPPH1 expression in leukocytes in addition to the screening algorithm used today had a significantly better performance. In conclusion, RPPH1 expression in leukocytes was significantly decreased in women with pre-eclampsia, and the expression at 22-24 weeks associated with the subsequent development of pre-eclampsia. RPPH1 in leukocytes may be a useful biomarker for prediction and/or early detection of pre-eclampsia and an unknown regulator of the signaling affecting immune cells.

Keywords: Pre-eclampsia; RPPH1; lncRNA.