Objective: To detect the expression of micro ribonucleic acid (miR)-152 in the placental tissues of preeclampsia (PE) rats and its correlation with the expression of vascular endothelial growth factor (VEGF), and to investigate the influence of miR-152 on the apoptosis of trophoblast cells.
Materials and methods: A Sprague Dawley (SD) rat model of PE was established, the total RNA and total protein in the placental tissues were extracted, and reverse transcription-polymerase chain reaction (RT-PCR) was applied to determine the expression level of miR-152 in the placental tissues. The rats were divided into miR-152 high expression group (High group) and miR-152 low expression group (Low group) according to the expression level of miR-152. RT-PCR, immunohistochemistry and Western blotting assay were performed to detect the expressions of VEGF messenger RNA (mRNA) and protein, respectively, in the placental tissues of the two groups of rats. Meanwhile, the BeWo trophoblast cell lines were used in in-vitro experiment, which were divided into Control group and miR-152 mimic group. 10 μL miR-152 mimic were added into each well plate in miR-152 mimic group, and 24 h later, TUNEL staining and flow cytometry were utilized to assess the cell apoptosis in both groups. At the same time, the expressions of B-cell lymphoma-2 (Bcl-2) and Bcl-2-associated X protein (Bax) in the two groups of cells were measured using Western blotting assay.
Results: The expression level of miR-152 in the placentas of PE rats was increased markedly compared with that of normal rats. The expression levels of VEGF mRNA and protein in the rat placenta in High group were notably higher than those in Low group. In vitro experiment results indicated that miR-152 mimic could promote the apoptosis of BeWo trophoblast cells, up-regulate the pro-apoptotic gene Bax and inhibit the anti-apoptotic gene Bcl-2 simultaneously.
Conclusions: The expression of miR-152 is increased in the placental tissues of PE rats, and it is positively correlated with VEGF. In addition, the increased miR-152 expression can promote the apoptosis of trophoblast cells.