Background: The goal of this study was to screen for differentially expressed exosomal miRNAs in peripheral blood samples of early-onset preeclampsia and normal pregnant patients using high-throughput sequencing methods and explore their effects on the pathogenesis of preeclampsia.
Methods: Peripheral blood samples from 5 patients with early-onset preeclampsia and 5 normal pregnant women (control group) were enrolled. Then, exosomes were extracted from each sample, and the procedure was replicated three times. An Illumina HiSeq4000 sequencing platform was used to analyze exosomal miRNAs in all samples before comparison. The target genes and signaling pathway predictions and the biological function enrichments of significant and differentially expressed miRNAs were assessed using Miranda and Starbase software, as well as GO and KEGG databases.
Results: Compared with the control, patients in the early-onset preeclampsia group had 65 significantly and differentially expressed exosomal miRNAs in their peripheral blood samples. The results have shown that of the 65 differentially expressed miRNAs, 17, including has-miR-6855, has-miR-7151, and has-miR-6777, were up-regulated, and 48, including has-miR-1247, has-miR-29B2, and has-miR-941, were down-regulated (p < 0.05). The Miranda and TargetScanS algorithms predicted a total of 2,231 target genes from the differentially expressed miRNAs. The Go and KEGG analyses showed that the principal biological function of these target genes was the regulation of Ras protein signal transduction, histone modification, GTPase-mediated signal transduction, and transforming growth factor (TGF)-β. Additionally, the results also showed that the major pathways involved in the regulation of these functions were the PI3K Akt, MAPK, tumor necrosis factor, and EGFR tyrosine kinase inhibition signaling pathways.
Conclusions: There are significant differences in the expression profiles of exosomal miRNAs between early-onset preeclampsia patients and normal pregnant women. These differentially expressed miRNAs may not only play an important regulatory role in the occurrence of early-onset preeclampsia but also participate in its pathophysiological process through genetic regulation of a variety of biological functions and signal pathways.