ABSTRACT
Circular RNA (circRNA) plays an important role in biological processes of gestational diabetes mellitus (GDM) and preeclampsia (PE). However, the mechanisms for circRNA DMNT1 (circ-DMNT1) in GDM and PE remain unclarified. The expression levels of circ-DMNT1 and p53 in GDM and PE were quantified by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot analysis. When the expression of circ-DMNT1 or p53 was abnormal, cell counting kit-8 (CCK-8) assay, bromodeoxyuridine (BrdU) staining, flow cytometry, cell scratch, and Transwell assays were used to assess cell viability, proliferation, cell cycle, apoptosis, migration, and invasion of trophoblast cells, respectively. Subsequently, the binding relationship between circ-DMNT1 and p53 was verified by RNA pull-down and RIP analysis, followed by the determination of JAK/STAT pathway-related protein expression levels using western blot analysis. Both circ-DMNT1 and p53 were highly expressed in GDM and PE. Upregulation of circ-DMNT1 or p53 inhibited trophoblast cell viability, proliferation, migration, and invasion, meanwhile promoting cell apoptosis but blocking cell cycle progression. However, downregulation of circ-DMNT1 or p53 induced trophoblast cell survival. In GDM and PE, circ-DMNT1 activated the JAK/STAT pathway by binding to p53, which resulted in increased expression levels of p-JAK and p-STAT. The results suggested that circ-DMNT1 was involved in the deterioration of GDM and PE, possibly through inducing p53 expression and activating the JAK/STAT signaling pathway.
ABSTRACT
BACKGROUND: Being one of the most prevalent metabolic and endocrine disorders, Polycystic Ovary Syndrome (PCOS) has been proven to be associated with microRNA-130b-3p (miR-130b-3p). However, the exact role played by miR-130b-3p in the pathogenesis and progression of PCOS remains unknown. Thus, this article is focused on elucidating the function of miR-130b-3p in the pathogenesis of PCOS. METHODS: The expression levels of miR-130b-3p and SMAD4 in tissues and cells responsible for the development of PCOS were determined by RT-qPCR and western blot. A miR-130b-3p mimic/inhibitor or si-SMAD4 were transfected into KGN cells. The cell viability was detected by CCK-8 and EDU methods. The activity of caspase-3 was measured by caspase-3 analysis. Subsequently, apoptosis and the cell cycle were measured via flow cytometry. The correlation between SMAD4 and miR-130b-3p was confirmed using an RNA pull-down assay and a dual luciferase reporter system assay. RESULTS: MiR-130b-3p was upregulated in the KGN cells and ovarian granulosa cells (GCs) of PCOS patients. It was found that miR-130b-3p overexpression or SMAD4 silencing can promote KGN cell proliferation and positive EDU rates, induce S phase arrest, inhibit apoptosis and caspase-3 activity. On the other hand, miR-130b-3p inhibitors reduce KGN cell proliferation, inhibit apoptosis and reverse the effect of si-SMAD4. CONCLUSION: MiR-130b-3p directly interacts with SMAD4 to induce KGN cell proliferation, inhibit apoptosis, suggesting that miR-130b-3p expression is positively correlated with the development of PCOS. This may serve as new evidence for the abnormal proliferation of GCs in PCOS.
