Abstract
Aims/introduction: Emerging evidence shows that epigenetic modifications occurring during fetal development in response to intrauterine exposures could be one of the mechanisms involved in the early determinants of adult metabolic disorders. This study aimed to investigate whether the placental maternally expressed gene 3 (MEG3) deoxyribonucleic acid (DNA) methylation profile is associated with maternal gestational diabetes mellitus status and newborn birthweight. Materials and methods: Samples for measurement were collected from 23 women with gestational diabetes mellitus and 23 healthy controls. MEG3 gene expression and DNA methylation levels were assessed using quantitative real-time polymerase chain reaction and MethylTargetTM, respectively. Pearson correlation analyses were used to examine associations between placental DNA methylation levels and clinical variables of interest. The associated results were adjusted by multivariate linear regression for maternal age, body mass index, height, gestational age and newborn sex as confounders. Results: We found that the DNA methylation levels in the MEG3 differentially methylated region were significantly different between the gestational diabetes mellitus and control groups on the maternal side of the placenta (40.64 ± 2.15 vs 38.33 ± 2.92; P = 0.004). Furthermore, the mean MEG3 DNA methylation levels were correlated positively with maternal fasting glucose concentrations (R = 0.603, P < 0.001) and newborn birthweight (R = 0.568, P < 0.001). Conclusions: The placental DNA methylation status in the MEG3 differentially methylated region was correlated with maternal glucose concentrations and newborn birthweight. These epigenetic adaptations might contribute to late-onset obesity, underlining the adverse intrauterine environment.