Eastwood, Kelly‐Ann

Objective: Preeclampsia is a cardiovascular complication characterised by the new onset of hypertension and proteinuria or other end-organ dysfunction. Currently there are no effective treatments for preeclampsia except delivery of the placenta and the baby, often pre-term. Administration of mesenchymal stem cells (MSCs) has shown therapeutic potential in pre-clinical models of preeclampsia. In this study, we aimed to identify novel placental miRNAs in preeclampsia which could be targeted by MSCs or their extracellular vesicles (MSC-EVs). Design and method: Human MSCs were isolated from abdominal fat tissue during caesarean section and cultured for 48 h. Human umbilical cord endothelial cells (HUVEC) were co-cultured with MSCs from pregnancies with or without preeclampsia (n = 3) up to 90 h and angiogenesis assessed using tubule formation assay in IncuCyteu live cell imaging system. Using separate patient samples, miRNA was isolated from placentae from women with and without preeclampsia (n = 2) and miRNA next generation sequencing (miRNAseq) performed. The expression of two miRNAs identified in miRNAseq (miRNA-183–5p and miRNA-203a-3p) were measured in HUVEC cells exposed to 24 h hypoxia (1%) or normoxia (21%) in the presence of MSC conditioned medium (MSC-CM) or MSC-EVs. Results: MSCs isolated from women with preeclampsia demonstrated impaired pro-angiogenic profile compared to MSCs derived from normotensive pregnancies measured by the network length (mm/m2) of HUVECs following 66 h, 72 h, 78 h, 84 h and 90 h of exposure to MSC-CM (n = 3, p = 0.001). The results of miRNAseq identified a number of aberrantly expressed miRNAs including mir-183–5p (logFC = -2.8, p = 0.001) and mir-203a-3p (logFC = -6.7, p = 0.001). Following exposure of HUVECs to hypoxia, mir-183–5p was significantly increased by approximately 8-fold (p = 0.001) whereas mir-203a-3p showed no change in expression. MSC-CM and MSC-EVs were both capable of ameliorating this increase in mir-183–5p as a result of hypoxia (p = 0.01, MSC-CM; p = 0.001, MSC-EVs). Conclusions: In patients with preeclampsia, MSCs show impaired angiogenic function, potentially leading to inappropriate placental development and angiogenesis in pregnancy. Administration of healthy MSCs or associated MSC-EVs could have a therapeutic potential in the treatment of preeclampsia and the mechanism could involve novel mir-183–5p as a treatment target.

Abstract Context Preeclampsia is a leading cardiovascular complication in pregnancy lacking effective diagnostic and treatment strategies. Objective To investigate the diagnostic and therapeutic target potential of the angiogenesis proteins, FK506-binding protein like (FKBPL) and CD44. Design and Intervention FKBPL and CD44 plasma concentration or placental expression were determined in women pre- or postdiagnosis of preeclampsia. Trophoblast and endothelial cell function was assessed following mesenchymal stem cell (MSC) treatment and in the context of FKBPL signaling. Settings and Participants Human samples prediagnosis (15 and 20 weeks of gestation; n ≥ 57), or postdiagnosis (n = 18 for plasma; n = 4 for placenta) of preeclampsia were used to determine FKBPL and CD44 levels, compared to healthy controls. Trophoblast or endothelial cells were exposed to low/high oxygen, and treated with MSC-conditioned media (MSC-CM) or a FKBPL overexpression plasmid. Main Outcome Measures Preeclampsia risk stratification and diagnostic potential of FKBPL and CD44 were investigated. MSC treatment effects and FKBPL-CD44 signaling in trophoblast and endothelial cells were assessed. Results The CD44/FKBPL ratio was reduced in placenta and plasma following clinical diagnosis of preeclampsia. At 20 weeks of gestation, a high plasma CD44/FKBPL ratio was independently associated with the 2.3-fold increased risk of preeclampsia (odds ratio = 2.3, 95% confidence interval [CI] 1.03-5.23, P = 0.04). In combination with high mean arterial blood pressure (>82.5 mmHg), the risk further increased to 3.9-fold (95% CI 1.30-11.84, P = 0.016). Both hypoxia and MSC-based therapy inhibited FKBPL-CD44 signaling, enhancing cell angiogenesis. Conclusions The FKBPL-CD44 pathway appears to have a central role in the pathogenesis of preeclampsia, showing promising utilities for early diagnostic and therapeutic purposes.