Gestational Diabetes Mellitus Is Associated with Age-Specific Alterations in Markers of Adiposity in Offspring: A Narrative Review

Gestational Diabetes Mellitus: Unveiling Maternal Health Dynamics from Pregnancy Through Postpartum Perspectives

Gestational Diabetes Mellitus (GDM) is the most frequent pregnancy-related medical issue and presents significant risks to both maternal and foetal health, requiring monitoring and management during pregnancy. The prevalence of GDM has surged globally in recent years, mirroring the rise in diabetes and obesity rates. Estimated to affect from 5% to 25% of pregnancies, GDM impacts approximately 21 million live births annually, according to the International Diabetes Federation (IDF). However, consensus on diagnostic approaches remains elusive, with varying recommendations from international organizations, which makes the comparison between research complicated. Compounding concerns are the short-term and long-term complications stemming from GDM for mothers and offspring. Maternal outcomes include heightened cardiovascular risks and a notable 70% risk of developing Type 2 Diabetes Mellitus (T2DM) within a decade postpartum. Despite this, research into the metabolic profiles associated with a previous GDM predisposing women to T2D remains limited. While genetic biomarkers have been identified, indicating the multifaceted nature of GDM involving hormonal changes, insulin resistance, and impaired insulin secretion, there remains a dearth of exploration into the enduring health implications for both mothers and their children. Furthermore, offspring born to mothers with GDM have been shown to face an increased risk of obesity and metabolic syndrome during childhood and adolescence, with studies indicating a heightened risk ranging from 20% to 50%. This comprehensive review aims to critically assess the current landscape of Gestational Diabetes Mellitus (GDM) research, focusing on its prevalence, diagnostic challenges, and health impacts on mothers and offspring. By examining state-of-the-art knowledge and identifying key knowledge gaps in the scientific literature, this review aims to highlight the multifaceted factors that have hindered a deeper understanding of GDM and its long-term consequences. Ultimately, this scholarly exploration seeks to promote further investigation into this critical area, improving health outcomes for mothers and their children.

Treating Gestational Diabetes Reduces Birth Weight but Does Not Affect Infant Adiposity Across the 1st Year of Life

OBJECTIVE

The continuum of maternal glycemia in pregnancy shows continuous associations with both 1) neonatal birth weight at delivery and 2) subsequent adiposity later in childhood. While treating gestational diabetes mellitus (GDM) can lower birth weight and thereby disrupt the former association, it is unclear if such treatment reduces childhood adiposity. Thus, we sought to compare anthropometry across the 1st year of life between infants born to women who were treated for GDM and those with lesser degrees of gestational dysglycemia (untreated).

RESEARCH DESIGN AND METHODS

Anthropometric measurements were performed at 3 months and 12 months of life in 567 infants born to women comprising the following four gestational glucose tolerance groups: 1) women with normoglycemia on both glucose challenge test (GCT) and oral glucose tolerance test (OGTT) in pregnancy; 2) women with an abnormal GCT but normal OGTT; 3) those with mild gestational impaired glucose tolerance; and 4) women treated for GDM.

RESULTS

Birth weight progressively increased across the three untreated groups but was lowest in women treated for GDM (P = 0.0004). Similarly, women treated for GDM had the lowest rate of macrosomia (P = 0.02). Conversely, however, there were no differences among the four groups in weight z score, length z score, weight-for-length z score, or BMI z score at either 3 months or 12 months (all P values = NS). Similarly, there were no differences among the groups in triceps/biceps/subscapular/suprailiac skinfold thickness or sum of skinfolds at either 3 months or 12 months (all P values = NS).

CONCLUSIONS

Despite reducing birth weight and macrosomia, the treatment of GDM does not have analogous effects on infant adiposity across the 1st year of life.

The therapeutic effects of attending a one-day outpatient service on patients with gestational diabetes and different pre-pregnancy body mass indices

Purpose

This study investigated the effects of attending a one-day outpatient service on the outcomes of patients with gestational diabetes mellitus (GDM) and different pre-pregnancy body mass indices (BMIs).

Methods

The study recruited 311 pregnant women with GDM into a one-day outpatient service at The Fourth Hospital of Shijiazhuang from September 2019 to December 2021. They were randomly assigned to three groups, based on their pre-pregnancy BMI as follows: group A, BMI < 18.5 kg/m²; group B, 18.5 ≥ BMI > 25.0 kg/m²; group C, BMI ≥25 kg/m². The following information was collected from all the participants: fasting blood glucose, hemoglobin A1c (HbA1C), insulin dose, gestational weight gain, weight gain after the one-day outpatient service, and perinatal outcomes.

Results

The three groups showed significant differences in fasting blood glucose and HbA1C, insulin treatment rate, and the incidence of pregnancy hypertension/preeclampsia and neonatal jaundice (all P < 0.05). The rate of excessive gestational weight gain in all of the groups also reflected significant differences (P < 0.05). Group A showed the lowest weight gain, while group C gained the most weight. There is no significant difference in the incidences of hypertension/preeclampsia, neonatal jaundice, or premature birth between patients with weight loss/no weight gain and those with positive weight gain.

Conclusion

One-day diabetes outpatient integrated management may effectively help to manage weight gain and blood glucose in patients with GDM and different pre-pregnancy BMIs. Dietary control after a GDM diagnosis may have helped to avoid weight gain entirely, as well as negative weight gain, but did not increase the risk of maternal and infant-related complications.

Differential Changes in Akt and AMPK Phosphorylation Regulating mTOR Activity in the Placentas of Pregnancies Complicated by Fetal Growth Restriction and Gestational Diabetes Mellitus With Large-For-Gestational Age Infants

Background: Dysregulation of placental mechanistic target of rapamycin (mTOR) activity has been implicated in the pathophysiology of pregnancies complicated by idiopathic fetal growth restriction (FGR) and gestational diabetes mellitus (GDM) with large-for-gestational-age (LGA) infants. However, the underlying mechanisms remain unclear.

Methods: We obtained placentas from women with normal pregnancies (n = 11) and pregnancies complicated by FGR (n = 12) or GDM with LGA infants (n = 12) to compare the levels of total and phosphorylated forms of Akt, AMPK, TSC2, and mTOR among the three groups and used primary cytotrophoblast cells isolated from 30 normal term placentas to study the effects of oxygen–glucose deprivation (OGD) and increasing glucose concentrations on the changes of these factors in vitro.

Results: Placentas from FGR pregnancies had lower phosphorylated Akt (p-Akt) levels (P < 0.05), higher p-AMPKα levels (P < 0.01), and lower mTOR phosphorylation (P < 0.05) compared to that of normal pregnant women. Conversely, women with GDM and LGA infants had higher p-Akt (P < 0.001), lower p-AMPKα (P < 0.05), and higher p-mTOR levels (P < 0.05) in the placentas than normal pregnant women. Furthermore, primary cytotrophoblast cells subjected to OGD had lower p-Akt and p-mTOR (both P < 0.05) and higher p-AMPKα levels (P < 0.05) than those cultured under standard conditions, but increasing glucose concentrations had opposite effects on the respective levels. Administering compound C, an AMPK inhibitor, did not significantly affect Akt phosphorylation but partially reversed mTOR phosphorylation. Administering LY294002, an Akt inhibitor, decreased p-mTOR levels, but did not change the levels of total and phosphorylated AMPKα.

Conclusion: These results suggest that Akt and AMPK are involved in the regulation of trophoblast mTOR activity in the placentas of pregnancies complicated by FGR and GDM with LGA infants.

Identification of Diagnostic CpG Signatures in Patients with Gestational Diabetes Mellitus via Epigenome-Wide Association Study Integrated with Machine Learning

Background

Gestational diabetes mellitus (GDM) is the most prevalent metabolic disease during pregnancy, but the diagnosis is controversial and lagging partly due to the lack of useful biomarkers. CpG methylation is involved in the development of GDM. However, the specific CpG methylation sites serving as diagnostic biomarkers of GDM remain unclear. Here, we aimed to explore CpG signatures and establish the predicting model for the GDM diagnosis.

Methods

DNA methylation data of GSE88929 and GSE102177 were obtained from the GEO database, followed by the epigenome-wide association study (EWAS). GO and KEGG pathway analyses were performed by using the clusterProfiler package of R. The PPI network was constructed in the STRING database and Cytoscape software. The SVM model was established, in which the β-values of selected CpG sites were the predictor variable and the occurrence of GDM was the outcome variable.

Results

We identified 62 significant CpG methylation sites in the GDM samples compared with the control samples. GO and KEGG analyses based on the 62 CpG sites demonstrated that several essential cellular processes and signaling pathways were enriched in the system. A total of 12 hub genes related to the identified CpG sites were found in the PPI network. The SVM model based on the selected CpGs within the promoter region, including cg00922748, cg05216211, cg05376185, cg06617468, cg17097119, and cg22385669, was established, and the AUC values of the training set and testing set in the model were 0.8138 and 0.7576. The AUC value of the independent validation set of GSE102177 was 0.6667.

Conclusion

We identified potential diagnostic CpG signatures by EWAS integrated with the SVM model. The SVM model based on the identified 6 CpG sites reliably predicted the GDM occurrence, contributing to the diagnosis of GDM. Our finding provides new insights into the cross-application of EWAS and machine learning in GDM investigation.

Gestational Diabetes Mellitus and Developmental Programming

During normal pregnancy, increased insulin resistance acts as an adaptation to enhance materno-foetal nutrient transfer and meet the nutritional needs of the developing foetus, particularly in relation to glucose requirements. However, about 1 in 6 pregnancies worldwide is affected by the inability of the mother's metabolism to maintain normoglycaemia, with the combination of insulin resistance and insufficient insulin secretion resulting in gestational diabetes mellitus (GDM). A growing body of epidemiologic work demonstrates long-term implications for adverse offspring health resulting from exposure to GDM in utero. The effect of GDM on offspring obesity and cardiometabolic health may be partly influenced by maternal obesity; this suggests that improving glucose and weight control during early pregnancy, or better still before conception, has the potential to lessen the risk to the offspring. The consequences of GDM for microbiome modification in the offspring and the impact upon offspring immune dysregulation are actively developing research areas. Some studies have suggested that GDM impacts offspring neurodevelopmental and cognitive outcomes; confirmatory studies will need to separate the effect of GDM exposure from the complex interplay of social and environmental factors. Animal and human studies have demonstrated the role of epigenetic modifications in underpinning the predisposition to adverse health in offspring exposed to suboptimal hyperglycaemic in utero environment. To date, several epigenome-wide association studies in human have extended our knowledge on linking maternal diabetes-related DNA methylation marks with childhood adiposity-related outcomes. Identification of such epigenetic marks can help guide future research to develop candidate diagnostic biomarkers and preventive or therapeutic strategies. Longer-term interventions and longitudinal studies will be needed to better understand the causality, underlying mechanisms, or impact of GDM treatments to optimize the health of future generations.