Endocrine Abstracts

Background: Gestational diabetes mellitus (GDM) is one of the most common complications during pregnancy, with a globally increasing incidence that significantly affects maternal and infant health. Currently, there is a lack of effective early diagnostic markers for GDM. Therefore, it is necessary to identify diagnostic biomarkers for early screening of GDM during pregnancy. Circular RNA (CircRNA) has been found to be a structurally unique non-coding RNA, more stable than linear RNA, and can be encapsulated in exosomes, playing a role in the pathogenesis of various diseases, making it a promising candidate biomarker for various diseases.

Methods: We compared the expression profiles of circRNAs in the serum samples of three GDM patients and three matched controls using high-throughput sequencing technology. The specificity of circRNAs was validated using Sanger sequencing and agarose gel electrophoresis. The stability of circRNAs was assessed through RNase R and actinomycin D experiments. The relative expression levels of circRNAs in serum samples were measured using RT-qPCR. A logistic regression model was constructed for early prediction of GDM using circRNAs. The overall performance of circRNAs and the constructed model for early prediction and diagnosis of GDM was evaluated using ROC curves. The correlation between circRNAs and OGTT levels was assessed using Pearson correlation analysis. The effects of circRNAs on proliferation, migration, invasion, apoptosis, and cell cycle of human trophoblast cells were investigated using CCK-8 assays, EdU staining, Transwell assays, and flow cytometry.

Results: Hsa_circ_0031560 and hsa_circ_0000793 were highly expressed in the serum of GDM patients, and their expression levels were also high in the early stages of GDM development. Both circRNAs were positively correlated with OGTT expression. Hsa_circ_0031560 and hsa_circ_0000793 effectively diagnosed GDM in different cohorts. Furthermore, the model constructed using these two circRNAs effectively differentiated between GDM and non-GDM groups, with an AUC value of 0.852 in the overall cohort. In subsequent in vitro functional experiments, knockdown of hsa_circ_0031560 and hsa_circ_0000793 promoted proliferation, migration, and invasion of human trophoblast cells (HTR-8), increased the proportion of cells in the S phase, and suppressed cell apoptosis. Finally, knockdown of hsa_circ_0031560 and hsa_circ_0000793 was found to inhibit IL-8 expression.

Conclusion: Our study revealed high expression of hsa_circ_0031560 and hsa_circ_0000793 in the serum of GDM patients and their impact on trophoblast cells, suggesting their potential as candidate biomarkers for early diagnosis of GDM.