Exosomal MicroRNA-325 Enhances Trophoblast Migration and Invasion Through Downregulation of Lethal-7b and Upregulation of Forkhead Box Protein O1 Expression in Preeclampsia

We aimed to explore the mechanism by how microRNA (miRNA)-325 derived from marrow mesenchymal stem cell exosomes (MSC-exos) affects the trophoblast progression in preeclampsia (PE). RT-qPCR detected the level of miRNA let-7b and FOXO1 in the placenta tissue of PE patients. Functional experiment was performed to analyze the effect of FOXO1 inhibitor and let-7b mimics on cell migration, invasion and apoptosis through Transwell assay and TUNEL staining. The trophoblast cell was co-cultured with overexpressed-miR-325 MSC-exos to measure gene expression and cell progression. let-7b was highly and FOXO1 was lowly expressed in PE placenta tissue. let-7b directly targeted and inhibited FOXO1 expression. Importantly, as miR-325 was internalized by trophoblast cells through MSC-exos, MSC-exos overexpressing miR-325 inhibited let-7b expression in trophoblasts, up-regulated FOXO1 and activated AKT signaling pathway. Further, MSC-exos treatment promoted invasion and migration of trophoblast cell and inhibited apoptosis. In conclusion, miR-325 derived from MSC-exos promotes the invasion and migration of trophoblast cells in PE through inhibition of let7b and upregulation of FOXO1.

PM10 Alters Trophoblast Cell Function and Modulates miR-125b-5p Expression

Air pollution is one of the largest global environmental health hazards that threaten premature mortality or morbidity. Particulate matter 10 (PM10) has been demonstrated to contribute to several human diseases via dysregulated miRNA expression. Trophoblast cells play a key role in implantation and placentation for a successful pregnancy. Nonetheless, the PM10 associated trophoblast cell functions during pregnancy and miRNA expression are still unknown. Our study showed that PM10 affected HTR-8/SVneo cell viability and also decreased cell proliferation, migration, and invasion. A high concentration of PM10 caused an increase in HTR-8/SVneo cell apoptosis. Treatment with PM10 induced inflammation through the upregulated IL-1β, IL-6, and TNF-α expression in trophoblast cells. In PM10-treated HTR-8/SVneo cells, miR-125b-5p expression was considerably increased and TXNRD1 was found to be negatively related to miR-125b-5p. Collectively, our findings revealed that PM10 could alter miR-125b-5p expression by targeting TXNRD1 and suppressing trophoblast cell functions. Additional investigations relating to the function of miR-125b-5p and its target on particulate pollution exposure in trophoblast are warranted for future biomarker or effective therapeutic approaches.