Maternal Diabetes Mellitus and Neonatal Outcomes in Bisha: A Retrospective Cohort Study

BACKGROUND

Maternal diabetes mellitus (MDM) is associated with increased risks for adverse neonatal outcomes. However, the impact of MDM on neonatal outcomes in Bisha, a city in Saudi Arabia, is not well documented. This study aims to investigate the impact of MDM on neonatal outcomes in the Maternity and Children's Hospital (MCH), Bisha, Saudi Arabia.

METHODS

A retrospective cohort study was conducted on 181 pregnant women with diabetes and their neonates who were diagnosed at the Maternity and Children's Hospital (MCH), Bisha, Saudi Arabia, between 5 October 2020 and 5 November 2022. The primary outcome was a composite of adverse neonatal outcomes, including stillbirth, neonatal death, macrosomia, preterm birth, respiratory distress syndrome, hypoglycemia, and congenital anomalies. Logistic regression analyses were used to adjust for potential confounders.

RESULTS

The total sample size was 181. The average age of patients was 34 years (SD = 6.45). The majority of the patients were diagnosed with GDM, 147 (81.2%), and pre-GDM, 34 (18.8%). Neonates born to mothers with MDM had a higher risk of adverse neonatal outcomes compared to those born to mothers without MDM (adjusted odds ratio [aOR] = 1.46, 95% confidence interval [CI]: 1.25-1.70). The risks of macrosomia (aOR = 1.74, 95% CI: 1.38-2.19), LBW (aOR = 1.32, 95% CI: 1.06-1.66), and RDS (aOR = 1.57, 95% CI: 1.28-1.93) were significantly higher among neonates born to mothers with MDM. The types of DM were statistically significant in terms of their correlation with the following neonatal outcomes: hypoglycemia (p-value = 0.017), macrosomia (p-value = 0.050), and neonatal death (p-value = 0.017).

CONCLUSIONS

MDM is associated with an increased risk of adverse neonatal outcomes in Bisha. The early identification and management of MDM may improve neonatal outcomes and reduce the burden of neonatal morbidity and mortality in this population.

MicroRNA-322 overexpression reduces neural tube defects in diabetic pregnancies

BACKGROUND

Hyperglycemia from pregestational diabetes mellitus induces neural tube defects in the developing fetus. Folate supplementation is the only effective way to prevent neural tube defects; however, some cases of neural tube defects are resistant to folate. Excess folate has been linked to higher maternal cancer risk and infant allergy. Therefore, additional interventions are needed. Understanding the mechanisms underlying maternal diabetes mellitus-induced neural tube defects can identify potential targets for preventing such defects. Despite not yet being in clinical use, growing evidence suggests that microRNAs are important intermediates in embryonic development and can serve as both biomarkers and drug targets for disease intervention. Our previous studies showed that maternal diabetes mellitus in vivo activates the inositol-requiring transmembrane kinase/endoribonuclease 1α (IRE1α) in the developing embryo and that a high glucose condition in vitro reduces microRNA-322 (miR-322) levels. IRE1α is an RNA endonuclease; however, it is unknown whether IRE1α targets and degrades miR-322 specifically or whether miR-322 degradation leads to neural tube defects via apoptosis. We hypothesize that IRE1α can inhibit miR-322 in maternal diabetes mellitus-induced neural tube defects and that restoring miR-322 expression in developing neuroepithelium ameliorates neural tube defects.

OBJECTIVE

This study aimed to identify potential targets for preventing maternal diabetes mellitus-induced neural tube defects and to investigate the roles and relationship of a microRNA and an RNA endonuclease in mouse embryos exposed to maternal diabetes mellitus.

STUDY DESIGN

To determine whether miR-322 reduction is necessary for neural tube defect formation in pregnancies complicated by diabetes mellitus, male mice carrying a transgene expressing miR-322 were mated with nondiabetic or diabetic wide-type female mice to generate embryos with or without miR-322 overexpression. At embryonic day 8.5 when the neural tube is not yet closed, embryos were harvested for the assessment of 3 miR-322 transcripts (primary, precursor, and mature miR-322), tumor necrosis factor receptor-associated factor 3 (TRAF3), and neuroepithelium cell survival. Neural tube defect incidences were determined in embryonic day 10.5 embryos when the neural tube should be closed if there is no neural tube defect formation. To identify which miR-322 transcript is affected by maternal diabetes mellitus and high glucose conditions, 3 miR-322 transcripts were assessed in embryos from dams with or without diabetes mellitus and in C17.2 mouse neural stem cells treated with different concentrations of glucose and at different time points. To determine whether the endonuclease IRE1α targets miR-322, small interfering RNA knockdown of IRE1α or overexpression of inositol-requiring transmembrane kinase/endoribonuclease 1α by DNA plasmid transfection was used to determine the effect of IRE1α deficiency or overexpression on miR-322 expression. RNA immunoprecipitation was performed to reveal the direct targets of inositol-requiring transmembrane kinase/endoribonuclease 1α.

RESULTS

Maternal diabetes mellitus suppressed miR-322 expression in the developing neuroepithelium. Restoring miR-322 expression in the neuroepithelium blocked maternal diabetes mellitus-induced caspase-3 and caspase-8 cleavage and cell apoptosis, leading to a neural tube defect reduction. Reversal of maternal diabetes mellitus-inhibited miR-322 via transgenic overexpression prevented TRAF3 up-regulation in embryos exposed to maternal diabetes mellitus. Activated IRE1α acted as an endonuclease and degraded precursor miR-322, resulting in mature miR-322 reduction.

CONCLUSION

This study supports the crucial role of the IRE1α-microRNA-TRAF3 circuit in the induction of neuroepithelial cell apoptosis and neural tube defect formation in pregnancies complicated by diabetes mellitus and identifies IRE1α and miR-322 as potential targets for preventing maternal diabetes mellitus-induced neural tube defects.

Effects of prenatal exposure to maternal diabetes mellitus on deep grey matter structures and attention deficit hyperactivity disorder symptoms in children

AIM

The neuronal mechanism linking the association between maternal diabetes mellitus (DM) and risk of attention deficit hyperactivity disorder (ADHD) symptoms and working memory deficits in children was investigated.

METHODS

A total of 6291 children (52% boys) born beyond 28 weeks of gestation were included and underwent brain magnetic resonance imaging scans at 9-10 years. Subcortical brain volumes were estimated from the T1-weighted images. ADHD symptoms were assessed using factorial analysis of the Child Behaviour Checklist completed by parents/caregivers. Working memory performance was assessed with the NIH Toolbox.

RESULTS

Compared to unexposed children, those exposed to DM (n = 422) had smaller (β = -0.15, p = 0.001) volumes of pooled deep grey matter (GM). Regional analysis revealed smaller volumes of the caudate nucleus, putamen, thalamus and cerebellum but not of hippocampus. They also had altered cortico-striatal white matter projection tracts. DM was not associated with working memory deficits or inattention, but with increased hyperactivity/impulsivity and Sluggish Cognitive Tempo symptoms in boys. This hyperactivity/impulsivity symptom in boys was partially mediated by smaller deep GM volume.

CONCLUSION

Exposure to DM during pregnancy leads to altered deep GM development during late childhood in their offspring. This contributed to an increased risk of hyperactivity/impulsivity symptoms in boys.

"Maternal diabetes mellitus and its impact on the risk of delivering a child with congenital heart disease: a systematic review and meta-analysis"

AIM

Maternal pregestational diabetes mellitus (PGDM), type 1 or type 2, has been established as a potential risk factor for congenital heart disease (CHD). At the same time, the correlation between gestational diabetes mellitus (GDM) and increased risk of CHD has not been yet fully elucidated. The objective of this systematic review and meta-analysis (PROSPERO number: CRD42020182390) was to analyze the existing evidence on PGDM and to attempt to fill, to the best of our ability, the remaining knowledge gap in the association of GDM with CHD.

MATERIALS AND METHODS

Two authors have independently searched the Pubmed/Medline, Scopus, Cochrane, Web of Science, and Theses Global databases with keywords and Boolean operators. The search yielded 9333 relevant articles, which were later screened for eligibility. Original peer-reviewed (case-control or cohort) studies were included if they were published in English between 1997 and 2020. Thirteen studies on mothers with PGDM and seven studies on mothers with GDM were finally included in our meta-analysis to investigate the association of maternal diabetes with the risk of delivering a child with CHD. The selected studies were all assessed for their methodological quality using the Newcastle-Ottawa scale. Associations with p < .05 were considered statistically significant.

RESULTS

Our meta-analysis (I² > 75%, total population: n = 12,461,586) of 79,476 women with PGDM and 160,893 with GDM produced an odds ratio of 3.48 (2.36-4.61) and 1.55 (1.48-1.61), respectively. Additionally, we did not find any noticeable difference in the risk for CHD among diabetic women living in the USA and Europe. Nevertheless, it still needs to be clarified, whether or not the gestational diabetic population includes undiagnosed women with preexisting diabetes, which might account for the increased risk of delivering a child with CHD in women classified as suffering from GDM.

CONCLUSION

While both GDM and PGDM seem to significantly increase the risk of CHD in comparison with the general population, PDGM appears to have a greater association with CHD, being correlated with a 3.5-fold increase in the risk of malformation. Preconceptional and gestational diabetes care are, therefore, essential to mitigate the adverse effect of hyperglycemia on fetal heart formation during pregnancy.

Association between maternal diabetes mellitus and allergic diseases in children - A systematic review and meta-analysis

BACKGROUND

Existing knowledge suggests that gestational diabetes mellitus was inconsistently associated with offspring allergic diseases. The aim of this study was to identify the association between maternal diabetes mellitus and the risk of offspring allergic diseases by systematic review.

METHODS

We searched and retrieved three databases (PubMed, Web of Science, and Cochrane Library) for articles on the association between maternal diabetes mellitus and offspring allergic diseases published before December 31, 2019. Stata software version 16.0 was used for statistical analysis.

RESULTS

Eight published studies were included in this meta-analysis. The pooled effect estimates showed the association between maternal diabetes mellitus and allergic outcomes, including asthma (OR: 1.13, 95% CI: 1.01-1.27), wheezing (OR: 1.13, 95% CI: 1.07-1.21), and atopic dermatitis (OR: 1.43, 95% CI: 1.22-1.57). Maternal diabetes mellitus was not associated with the risk of allergic sensitization, with a pooled effect estimate of 1.07 (95% CI: 0.45, 2.58).

CONCLUSION

Maternal diabetes mellitus may increase the risk of allergic diseases in their children. However, this finding should be validated with future large-sample epidemiological studies covering a wider spectrum of allergic diseases.

Maternal Obesity and Diabetes Mellitus as Risk Factors for Congenital Heart Disease in the Offspring

Congenital heart disease (CHD) is the most common anatomical malformation occurring live‐born infants and an increasing cause of morbidity and mortality across the lifespan and throughout the world. Population‐based observations have long described associations between maternal cardiometabolic disorders and the risk of CHD in the offspring. Here we review the epidemiological evidence and clinical observations relating maternal obesity and diabetes mellitus to the risk of CHD offspring with particular attention to mechanistic models of maternal‐fetal risk transmission and first trimester disturbances of fetal cardiac development. A deeper understanding of maternal risk factors holds the potential to improve both prenatal detection of CHD by identifying at‐risk pregnancies, along with primary prevention of disease by improving preconception and prenatal treatment of at‐risk mothers.

The reduction in FOXA2 activity during lung development in fetuses from diabetic rat mothers is reversed by Akt inhibition

Hyperglycemia during pregnancy is associated with fetal lung development disorders and surfactant protein (SP) deficiency. Here, we examined the role of FOXA2 and Akt signaling in fetal lung development during diabetic pregnancy. Sprague‐Dawley rats were injected with streptozocin (STZ) during pregnancy to induce diabetes (DM). DM‐exposed fetal lungs exhibited reduced numbers of alveoli, irregularities in the appearance and thickness of the alveolar septum, increased levels of glycogen and lipids in type II alveolar epithelial cells, fewer microvilli and mature lamellar bodies, and swollen mitochondria. SP‐B and SP‐C in DM amniotic fluid and DM lungs were lower than in the control group (P < 0.05). DM lung nuclear FOXA2 was lower compared with the control group (P < 0.05), but p‐FOXA2 was higher (P < 0.05). In murine lung epithelial (MLE) 12 cells, p‐AKT levels were increased by high glucose/insulin, but decreased by the Akt inhibitor MK2206 (P < 0.05). Expression of nuclear FOXA2 was increased by MK2206 compared with the high glucose/insulin group (P < 0.05). These results suggest that maternal diabetes induces fetal lung FOXA2 phosphorylation through the Akt pathway, and also affects the maturation of alveolar epithelial cells and reduces levels of SP‐B and SP‐C in the fetal lungs. An Akt inhibitor reversed the changes in SP expression in vitro.

Prenatal diagnosis of caudal regression syndrome and omphalocele in a fetus of a diabetic mother

The caudal regression syndrome is defined as total or partial agenesis of the sacrum and lumbar spine, frequently associated with other developmental malformations (orthopedic, neurological, genito-urinary, gastrointestinal…). Prenatal diagnosis is possible through fetal ultrasound (US) and magnetic resonance imaging (MRI). A case of fetal caudal regression syndrome with omphalocele from a diabetic mother is presented, demonstrating the sonographic, MRI, CT and X-Ray features diagnostic. We will also discuss neonatal findings, risk factors and prognosis of this condition.

Decidual arteriolopathy with or without associated hypertension modifies the underlying histomorphology in placentas from diabetic mothers

AIM

The aim of this study was to retrospectively document the impact of hypertensive conditions in pregnancy and decidual arteriolopathy on the patterns of placental injury in maternal diabetes mellitus (MDM).

METHODS

Among all 5248 > 20 weeks' placentas, the frequencies of 19 selected clinical and 24 placental phenotypes were compared between 287 MDM placentas and 4961 remaining placentas (control group [CG]) before and after further exclusion of 85 and 611 patients with hypertensive conditions (gestational hypertension, pre-eclampsia, chronic hypertension).

RESULTS

Cesarean section rate, heavy placentas, decidual arteriolopathy, microscopic chorionic pseudocysts, and chorangiosis were more common in MDM than in the CG both before and after exclusion of hypertensive conditions. The frequencies of preuterine patterns of chronic hypoxic placental injury and plasma cell deciduitis became statistically significant only after exclusion of hypertensive conditions.

CONCLUSION

Hypertensive conditions of pregnancy may obscure the underlying preuterine placental hypoxic pattern in MDM placentas. Even in normotensive patients, decidual arteriolopathy, and shallow placental implantation significantly impact placental histomorphology in MDM.

New development of the yolk sac theory in diabetic embryopathy: molecular mechanism and link to structural birth defects

Maternal diabetes mellitus is a significant risk factor for structural birth defects, including congenital heart defects and neural tube defects. With the rising prevalence of type 2 diabetes mellitus and obesity in women of childbearing age, diabetes mellitus-induced birth defects have become an increasingly significant public health problem. Maternal diabetes mellitus in vivo and high glucose in vitro induce yolk sac injuries by damaging the morphologic condition of cells and altering the dynamics of organelles. The yolk sac vascular system is the first system to develop during embryogenesis; therefore, it is the most sensitive to hyperglycemia. The consequences of yolk sac injuries include impairment of nutrient transportation because of vasculopathy. Although the functional relationship between yolk sac vasculopathy and structural birth defects has not yet been established, a recent study reveals that the quality of yolk sac vasculature is related inversely to embryonic malformation rates. Studies in animal models have uncovered key molecular intermediates of diabetic yolk sac vasculopathy, which include hypoxia-inducible factor-1α, apoptosis signal-regulating kinase 1, and its inhibitor thioredoxin-1, c-Jun-N-terminal kinases, nitric oxide, and nitric oxide synthase. Yolk sac vasculopathy is also associated with abnormalities in arachidonic acid and myo-inositol. Dietary supplementation with fatty acids that restore lipid levels in the yolk sac lead to a reduction in diabetes mellitus-induced malformations. Although the role of the human yolk in embryogenesis is less extensive than in rodents, nevertheless, human embryonic vasculogenesis is affected negatively by maternal diabetes mellitus. Mechanistic studies have identified potential therapeutic targets for future intervention against yolk sac vasculopathy, birth defects, and other complications associated with diabetic pregnancies.

Maternal diabetes causes alterations of DNA methylation statuses of some imprinted genes in murine oocytes

Maternal diabetes has adverse effects not only on oocyte quality but also on embryo development. However, it is still unknown whether the DNA imprinting in oocytes is altered by diabetes. By using streptozotocin (STZ)-induced and nonobese diabetic (NOD) mouse models we investigated the effect of maternal diabetes on DNA methylation of imprinted genes in oocytes. Mice which were judged as being diabetic 4 days after STZ injection were used for experiments. In superovulated oocytes of diabetic mice, the methylation pattern of Peg3 differential methylation regions (DMR) was affected in a time-dependent manner, and evident demethylation was observed on Day 35 after STZ injection. The expression level of DNA methyltransferases (DNMTs) was also decreased in a time-dependent manner in diabetic oocytes. However, the methylation patterns of H19 and Snrpn DMRs were not significantly altered by maternal diabetes, although there were some changes in Snrpn. In NOD mice, the methylation pattern of Peg3 was similar to that of STZ-induced mice. Embryo development was adversely affected by maternal diabetes; however, no evident imprinting abnormality was observed in oocytes from female offspring derived from a diabetic mother. These results indicate that maternal diabetes has adverse effects on DNA methylation of maternally imprinted gene Peg3 in oocytes of a diabetic female in a time-dependent manner, but methylation in offspring's oocytes is normal.