Circulating microRNA (miRNA) Expression Profiling in Plasma of Patients with Gestational Diabetes Mellitus Reveals Upregulation of miRNA miR-330-3p

Abstract

Gestational diabetes mellitus (GDM) is characterized by insulin resistance accompanied by low/absent beta-cell compensatory adaptation to the increased insulin demand. Although the molecular mechanisms and factors acting on beta-cell compensatory response during pregnancy have been partially elucidated and reported, those inducing an impaired beta-cell compensation and function, thus evolving in GDM, have yet to be fully addressed. MicroRNAs (miRNAs) are a class of small endogenous non-coding RNAs, which negatively modulate gene expression through their sequence-specific binding to 3′UTR of mRNA target. They have been described as potent modulators of cell survival and proliferation and, furthermore, as orchestrating molecules of beta-cell compensatory response and function in diabetes. Moreover, it has been reported that miRNAs can be actively secreted by cells and found in many biological fluids (e.g., serum/plasma), thus representing both optimal candidate disease biomarkers and mediators of tissues crosstalk(s). Here, we analyzed the expression profiles of circulating miRNAs in plasma samples obtained from n = 21 GDM patients and from n = 10 non-diabetic control pregnant women (24–33 weeks of gestation) using TaqMan array microfluidics cards followed by RT-real-time PCR single assay validation. The results highlighted the upregulation of miR-330-3p in plasma of GDM vs non-diabetics. Furthermore, the analysis of miR-330-3p expression levels revealed a bimodally distributed GDM patients group characterized by high or low circulating miR-330 expression and identified as GDM-miR-330high and GDM-miR-330low. Interestingly, GDM-miR-330high subgroup retained lower levels of insulinemia, inversely correlated to miR-330-3p expression levels, and a significant higher rate of primary cesarean sections. Finally, miR-330-3p target genes analysis revealed major modulators of beta-cell proliferation and of insulin secretion, such as the experimentally validated genes E2F1 and CDC42 as well as AGT2R2, a gene involved in the differentiation of mature beta-cells. In conclusion, we demonstrated that plasma miR-330-3p could be of help in identifying GDM patients with potential worse gestational diabetes outcome; in GDM, miR-330-3p may directly be transferred from plasma to beta-cells thus modulating key target genes involved in proliferation, differentiation, and insulin secretion.

MiR‐330‐3p contributes to INS‐1 cell dysfunction by targeting glucokinase in gestational diabetes mellitus

“…GDM is a pregnancy‐specific disease, and our inadequate understanding of the exact etiology and pathogenesis of GDM limits to the prevention and treatment of this disease . It has been increasingly recognized that miRNA are importantly associated with various diseases including GDM through post‐transcriptional regulation of gene expression . Therefore, identifying some GDM‐associated miRNA and investigating their clinical significance and functions are urgent.…”

“…Normal pregnant women (n = 10) and pregnant women with GDM (n = 30) were selected to study. All the patients performed a 75‐g oral glucose tolerance test at 16–19 weeks or 24–28 weeks of pregnancy, and GDM was diagnosed if one of the three glucose concentrations measured was above the cutoff values (fasting plasma glucose ≥5.1 mmoL/L; 1‐h plasma glucose ≥10 mmoL/L; 2‐h plasma glucose ≥8.5 mmoL/L), according to Italian guidelines . Patients with serious liver or kidney diseases, malignancy and acute heart failure were excluded.…”

“…GDM refers to any level of carbohydrate intolerance during the mid‐late pregnancy and the symptoms that pregnant women have not experienced before pregnancy . The prevalence of GDM ranging from 8.9 to 53.4% in the world and is rising every year . Although the pathophysiological mechanisms of GDM have not been fully elucidated, it was well known that the insufficient adaptability of pancreatic β cell to insulin resistance, which is characterized by mid‐late pregnancy, maybe the primary cause of GDM .…”

“…In recent years, microRNA (miRNA) have been well recognized, and have been proved that they can be used as biomarkers in various diseases, including GDM . In addition, many research studies have confirmed that miRNA own major function in the regulation of pancreatic β cells biological functions, which take part in the pathogenesis and progression of GDM, for example, miR‐503 was reported to lead to the dysfunction of β cells in GDM; miR‐19a‐3p was reported to enhance β cell proliferation and insulin secretion and inhibit the cell apoptosis in GDM; and it was proved that miR‐18 can contribute to the abnormal function of β cells in GDM .…”

“…In addition, many research studies have confirmed that miRNA own major function in the regulation of pancreatic β cells biological functions, which take part in the pathogenesis and progression of GDM, for example, miR‐503 was reported to lead to the dysfunction of β cells in GDM; miR‐19a‐3p was reported to enhance β cell proliferation and insulin secretion and inhibit the cell apoptosis in GDM; and it was proved that miR‐18 can contribute to the abnormal function of β cells in GDM . In addition, there is research which has reported that high expression of miR‐330‐3p has been found in GDM . miR‐330‐3p has been reported by many articles to have important regulating effect on various diseases, for instance, Liu et al .…”