RANK links thymic regulatory T cells to fetal loss and gestational diabetes in pregnancy.

Successful pregnancies rely on adaptations within the mother1, including marked changes within the immune system2. It has long been known that the thymus, the central lymphoid organ, changes markedly during pregnancy3. However, the molecular basis and importance of this process remain largely obscure. Here we show that the osteoclast differentiation receptor RANK4,5 couples female sex hormones to the rewiring of the thymus during pregnancy. Genetic deletion of Rank (also known as Tnfrsf11a) in thymic epithelial cells results in impaired thymic involution and blunted expansion of natural regulatory T (Treg) cells in pregnant female mice. Sex hormones, in particular progesterone, drive the development of thymic Treg cells through RANK in a manner that depends on AIRE+ medullary thymic epithelial cells. The depletion of Rank in the mouse thymic epithelium results in reduced accumulation of natural Treg cells in the placenta, and an increase in the number of miscarriages. Thymic deletion of Rank also results in impaired accumulation of Treg cells in visceral adipose tissue, and is associated with enlarged adipocyte size, tissue inflammation, enhanced maternal glucose intolerance, fetal macrosomia, and a long-lasting transgenerational alteration in glucose homeostasis, which are all key hallmarks of gestational diabetes. Transplantation of Treg cells rescued fetal loss, maternal glucose intolerance and fetal macrosomia. In human pregnancies, we found that gestational diabetes also correlates with a reduced number of Treg cells in the placenta. Our findings show that RANK promotes the hormone-mediated development of thymic Treg cells during pregnancy, and expand the functional role of maternal Treg cells to the development of gestational diabetes and the transgenerational metabolic rewiring of glucose homeostasis.

Beta-cell compensation and gestational diabetes.

Gestational diabetes mellitus (GDM) is characterized by glucose intolerance in pregnant women without a previous diagnosis of diabetes. While the etiology of GDM remains elusive, the close association of GDM with increased maternal adiposity and advanced gestational age implicates insulin resistance as a culpable factor for the pathogenesis of GDM. Pregnancy is accompanied by the physiological induction of insulin resistance in the mother secondary to maternal weight gain. This effect serves to spare blood glucose for the fetus. To overcome insulin resistance, maternal ß-cells are conditioned to release more insulin into the blood. Such an adaptive response, termed ß-cell compensation, is essential for maintaining normal maternal metabolism. ß-cell compensation culminates in the expansion of ß-cell mass and augmentation of ß-cell function, accounting for increased insulin synthesis and secretion. As a result, a vast majority of mothers are protected from developing GDM during pregnancy. In at-risk pregnant women, ß-cells fail to compensate for maternal insulin resistance, contributing to insulin insufficiency and GDM. However, gestational ß-cell compensation ensues in early pregnancy, prior to the establishment of insulin resistance in late pregnancy. How ß-cells compensate for pregnancy and what causes ß-cell failure in GDM are subjects of investigation. In this mini-review, we will provide clinical and preclinical evidence that ß-cell compensation is pivotal for overriding maternal insulin resistance to protect against GDM. We will highlight key molecules whose functions are critical for integrating gestational hormones to ß-cell compensation for pregnancy. We will provide mechanistic insights into ß-cell decompensation in the etiology of GDM.

Placenta-derived exosomal miR-135a-5p promotes gestational diabetes mellitus pathogenesis by activating PI3K/AKT signalling pathway via SIRT1.

Most people are aware of gestational diabetes mellitus (GDM), a dangerous pregnancy complication in which pregnant women who have never been diagnosed with diabetes develop chronic hyperglycaemia. Exosomal microRNA (miRNA) dysregulation has been shown to be a key player in the pathophysiology of GDM. In this study, we looked into how placental exosomes and their miRNAs may contribute to GDM. When compared to exosomes from healthy pregnant women, it was discovered that miR-135a-5p was elevated in placenta-derived exosomes that were isolated from the maternal peripheral plasma of GDM women. Additionally, we discovered that miR-135a-5p encouraged HTR-8/SVneo cell growth, invasion and migration. Further research revealed that miR-135a-5p activates HTR-8/SVneo cells' proliferation, invasion and migration by promoting PI3K/AKT pathway activity via Sirtuin 1 (SIRT1). The transfer of exosomal miR-135a-5p generated from the placenta could be viewed as a promising agent for targeting genes and pertinent pathways involved in GDM, according to our findings.

High TXNIP expression accelerates the migration and invasion of the GDM placenta trophoblast.

INTRODUCTION: Our previous study has proofed the glucose sensitive gene-thioredoxin-interacting protein (TXNIP) expression was up in the placenta of the patients with gestational diabetes mellitus (GDM), but the pathological mechanisms underlying abnormal TXNIP expression in the placenta of patients with GDM is completely unclear and additional investigations are required to explain the findings we have observed. In the present study, we simulated the high TXNIP expression via introducing the Tet-On "switch" in vitro, approximate to its expression level in the real world, to explore the following consequence of the abnormal TXNIP. METHODS: The expression and localization of TXNIP in the placenta of GDM patients and the health control was investigated via immunofluorescent staining, western blot and RT-qPCR. Overexpression of TXNIP was achieved through transfecting Tet-on system to the human trophoblastic cell line-HTR-8/Svneo cell. TXNIP knockout was obtained via CRISPR-Cas9 method. The cell phenotype was observed via IncuCyte Imaging System and flow cytometry. The mechanism was explored via western blot and RT-qPCR. RESULTS: The expression level of TXNIP in the GDM placenta was nearly 2-3 times higher than that in the control. The TXNIP located at trophoblastic cells of the placenta. When the expression of TXNIP was upregulated, the migration and invasion of the cells accelerated, but cell apoptosis and proliferation did not changed compared with the control group. Furthermore, the size of the TetTXNIP cells became larger, and the expression level of Vimentin and p-STAT3 increased in the TetTXNIP cells. All the changes mentioned above were opposite in the TXNIP-KO cells. CONCLUSIONS: Abnormal expression of TXNIP might be related to the impairment of the GDM placental function, affecting the migration and invasion of the placental trophoblast cells through STAT3 and Vimentin related pathway; thus, TXNIP might be the potential therapeutic target for repairing the placental dysfunction deficient in GDM patients.

Gestational Diabetes History and Glucose Tolerance After Pregnancy Associated With Coronary Artery Calcium in Women During Midlife: The CARDIA Study.

BACKGROUND: Gestational diabetes (GD) leads to earlier onset and heightened risk of type 2 diabetes, a strong risk factor for cardiovascular disease (CVD). However, it is unclear whether attaining normoglycemia can ameliorate the excess CVD risk associated with GD history. This study sought to evaluate GD history and glucose tolerance after pregnancy associated with coronary artery calcification (CAC) in women, a manifestation of atherosclerotic CVD and a predictor of CVD clinical events. METHODS: Data were obtained from the CARDIA study (Coronary Artery Risk Development in Young Adults), a US multicenter, community-based prospective cohort of young Black (50%) and White adults aged 18 to 30 years at baseline (1985-1986). The sample included 1133 women without diabetes at baseline, who had ≥1 singleton births (n=2066) during follow-up, glucose tolerance testing at baseline and up to 5 times during 25 years (1986-2011), GD status, and CAC measurements obtained from 1 or more follow up examinations at years 15, 20, and 25 (2001-2011). CAC was measured by noncontrast cardiac computed tomography; dichotomized as Any CAC (score>0) or No CAC (score=0). Complementary log-log models for interval-censored data estimated adjusted hazard ratios of CAC and 95% confidence intervals for GD history and subsequent glucose tolerance groups (normoglycemia, prediabetes, or incident diabetes) on average 14.7 years after the last birth adjusted for prepregnancy and follow-up covariates. RESULTS: Of 1133 women, 139 (12.3%) reported GD and were 47.6 years of age (4.8 SD) at follow-up. CAC was present in 25% (34/139) of women with GD and 15% (149/994) of women with no GD. In comparison with no GD/normoglycemia, adjusted hazard ratios (95% CIs) were 1.54 (1.06-2.24) for no GD/prediabetes and 2.17 (1.30-3.62) for no GD/incident diabetes, and 2.34 (1.34-4.09), 2.13 (1.09-4.17), and 2.02 (0.98-4.19) for GD/normoglycemia, GD/prediabetes, and GD/incident diabetes, respectively (overall P=0.003). CONCLUSIONS: Women without previous GD showed a graded increase in the risk of CAC associated with worsening glucose tolerance. Women with a history of GD had a 2-fold higher risk of CAC across all subsequent levels of glucose tolerance. Midlife atherosclerotic CVD risk among women with previous GD is not diminished by attaining normoglycemia.

Breastfeeding may benefit cardiometabolic health of children exposed to increased gestational glycemia in utero.

PURPOSE: There is altered breastmilk composition among mothers with gestational diabetes and conflicting evidence on whether breastfeeding is beneficial or detrimental to their offspring's cardiometabolic health. We aimed to investigate associations between breastfeeding and offspring's cardiometabolic health across the range of gestational glycemia. METHODS: We included 827 naturally conceived, term singletons from a prospective mother-child cohort. We measured gestational (26-28 weeks) fasting plasma glucose (FPG) and 2-h plasma glucose (2 hPG) after an oral glucose tolerance test as continuous variables. Participants were classified into 2 breastfeeding categories (high/intermediate vs. low) according to their breastfeeding duration and exclusivity. Main outcome measures included magnetic resonance imaging (MRI)-measured abdominal fat, intramyocellular lipids (IMCL), and liver fat, quantitative magnetic resonance (QMR)-measured body fat mass, blood pressure, blood lipids, and insulin resistance at 6 years old (all continuous variables). We evaluated if gestational glycemia (FPG and 2 hPG) modified the association of breastfeeding with offspring outcomes after adjusting for confounders using a multiple linear regression model that included a 'gestational glycemia × breastfeeding' interaction term. RESULTS: With increasing gestational FPG, high/intermediate (vs. low) breastfeeding was associated with lower levels of IMCL (p-interaction = 0.047), liver fat (p-interaction = 0.033), and triglycerides (p-interaction = 0.007), after adjusting for confounders. Specifically, at 2 standard deviations above the mean gestational FPG level, high/intermediate (vs. low) breastfeeding was linked to lower adjusted mean IMCL [0.39% of water signal (0.29, 0.50) vs. 0.54% of water signal (0.46, 0.62)], liver fat [0.39% by weight (0.20, 0.58) vs. 0.72% by weight (0.59, 0.85)], and triglycerides [0.62 mmol/L (0.51, 0.72) vs. 0.86 mmol/L (0.75, 0.97)]. 2 hPG did not significantly modify the association between breastfeeding and childhood cardiometabolic risk. CONCLUSION: Our findings suggest breastfeeding may confer protection against adverse fat partitioning and higher triglyceride concentration among children exposed to increased glycemia in utero.

Abnormal placental villous maturity and dysregulated glucose metabolism: implications for stillbirth prevention.

OBJECTIVES: In the UK one in 250 pregnancies end in stillbirth. Abnormal placental villous maturation, commonly associated with gestational diabetes, is a risk factor for stillbirth. Histopathology reports of placental distal villous immaturity (DVI) are reported disproportionately in placentas from otherwise unexplained stillbirths in women without formal diagnosis of diabetes but with either clinical characteristics or risk factors for diabetes. This study aims to establish maternal factors associated with DVI in relation to stillbirth. METHODS: Placental histopathology reports were reviewed for all pregnant women delivering at University College London Hospital between July 2018 to March 2020. Maternal characteristics and birth outcomes of those with DVI were compared to those with other placental lesions or abnormal villous maturation. RESULTS: Of the 752 placental histopathology reports reviewed, 11 (1.5%) were reported as diagnostic of DVI. Eighty cases were sampled for clinical record analysis. All women with DVI had normal PAPP-A (>0.4 MoM), normal uterine artery Doppler studies (UtA-PI) and were normotensive throughout pregnancy. Nearly one in five babies (2/11, 18.5%) with DVI were stillborn and 70% had at least one high glucose test result in pregnancy despite no formal diagnosis of diabetes. CONCLUSIONS: These findings suggest that the mechanism underlying stillbirth in DVI likely relates to glucose dysmetabolism, not sufficient for diagnosis using current criteria for gestational diabetes, resulting in placental dysfunction that is not identifiable before the third trimester. Relying on conventional diabetes tests, foetal macrosomia or growth restriction, may not identify all pregnancies at risk of adverse outcomes from glucose dysmetabolism.

Oestrogen receptor α in T cells controls the T cell immune profile and glucose metabolism in mouse models of gestational diabetes mellitus.

AIMS/HYPOTHESIS: The imbalance between maternal insulin resistance and a relative lack of insulin secretion underlies the pathogenesis of gestational diabetes mellitus (GDM). Alterations in T cell subtypes and increased levels of circulating proinflammatory cytokines have been proposed as potential mechanisms underlying the pathophysiology of insulin resistance in GDM. Since oestrogen modulates T cell immunity, we hypothesised that oestrogen plays a homeostatic role in visceral adipose tissue by coordinating T cell immunity through oestrogen receptor α (ERα) in T cells to prevent GDM. METHODS: Female CD4-cre ERαfl/fl (KO) mice on a C57BL/6 background with ERα ablation specifically in T cells, and ERαfl/fl (ERα-floxed [FL]) mice were fed 60 kJ% high-fat diet (HFD) for 4 weeks. Female mice mated with male BALB/c mice to achieve allogenic pregnancy and were maintained on an HFD to generate the GDM model. Mice were divided into four experimental groups: non-pregnant FL, non-pregnant KO, pregnant FL (FL-GDM) and pregnant KO (KO-GDM). GTTs and ITTs were performed on day 12.5 or 13.5 and 16.5 after breeding, respectively. On day 18.5 after breeding, mice were killed and T cell subsets in the gonadal white adipose tissue (gWAT) and spleen were analysed using flow cytometry. Histological examination was also conducted and proinflammatory gene expression in gWAT and the liver was evaluated. RESULTS: KO mice that mated with BALB/c mice showed normal fertility rates and fetal weights as compared with FL mice. Body and tissue weights were similar between FL and KO mice. When compared with FL-GDM mice, KO-GDM mice showed decreased insulin secretion (serum insulin concentration 15 min after glucose loading: 137.3 ± 18.3 pmol/l and 40.1 ± 36.5 pmol/l, respectively; p < 0.05), impaired glucose tolerance (glucose AUC in GTT: 2308.3 ± 54.0 mmol/l × min and 2620.9 ± 122.1 mmol/l × min, respectively; p < 0.05) and increased numbers of T helper (Th)17 cells in gWAT (0.4 ± 0.0% vs 0.8 ± 0.1%; p < 0.05). However, the contents of Th1 and regulatory T cells (Tregs) in gWAT remained similar between FL-GDM and KO-GDM. Glucose-stimulated insulin secretion was similar between isolated islets derived from FL and KO mice, but was reduced by IL-17A treatment. Moreover, the levels of proinflammatory gene expression, including expression of Emr1 and Tnfa in gWAT, were significantly higher in KO-GDM mice than in FL-GDM mice (5.1-fold and 2.7-fold, respectively; p < 0.01 for both). Furthermore, KO-GDM mice showed increased expression of genes encoding hepatokines, Ahsg and Fgf21 (both were 2.4-fold higher vs FL-GDM mice; p < 0.05 and p = 0.09, respectively), with no changes in inflammatory gene expression (e.g., Tnfa and Ifng) in the liver compared with FL-GDM mice. CONCLUSIONS/INTERPRETATION: Deletion of ERα in T cells caused impaired maternal adaptation of insulin secretion, changes in hepatokine profiles, and enhanced chronic inflammation in gWAT alongside an abnormal increase in Th17 cells. These results suggest that the ERα-mediated oestrogen signalling effects in T cells regulate T cell immunity and contribute to glucose homeostasis in pregnancy.

GestAltNet: aggregation and attention to improve deep learning of gestational age from placental whole-slide images.

The placenta is the first organ to form and performs the functions of the lung, gut, kidney, and endocrine systems. Abnormalities in the placenta cause or reflect most abnormalities in gestation and can have life-long consequences for the mother and infant. Placental villi undergo a complex but reproducible sequence of maturation across the third-trimester. Abnormalities of villous maturation are a feature of gestational diabetes and preeclampsia, among others, but there is significant interobserver variability in their diagnosis. Machine learning has emerged as a powerful tool for research in pathology. To capture the volume of data and manage heterogeneity within the placenta, we developed GestaltNet, which emulates human attention to high-yield areas and aggregation across regions. We used this network to estimate the gestational age (GA) of scanned placental slides and compared it to a baseline model lacking the attention and aggregation functions. In the test set, GestaltNet showed a higher r2 (0.9444 vs. 0.9220) than the baseline model. The mean absolute error (MAE) between the estimated and actual GA was also better in the GestaltNet (1.0847 weeks vs. 1.4505 weeks). On whole-slide images, we found the attention sub-network discriminates areas of terminal villi from other placental structures. Using this behavior, we estimated GA for 36 whole slides not previously seen by the model. In this task, similar to that faced by human pathologists, the model showed an r2 of 0.8859 with an MAE of 1.3671 weeks. We show that villous maturation is machine-recognizable. Machine-estimated GA could be useful when GA is unknown or to study abnormalities of villous maturation, including those in gestational diabetes or preeclampsia. GestaltNet points toward a future of genuinely whole-slide digital pathology by incorporating human-like behaviors of attention and aggregation.

Lower iodine storage in the placenta is associated with gestational diabetes mellitus.

BACKGROUND: The micronutrient iodine is essential for a healthy intrauterine environment and is required for optimal fetal growth and neurodevelopment. Evidence linking urinary iodine concentrations, which mainly reflects short-term iodine intake, to gestational diabetes mellitus (GDM) is inconclusive. Although the placental concentrations would better reflect the long-term gestational iodine status, no studies to date have investigated the association between the placental iodine load and the risk at GDM. Moreover, evidence is lacking whether placental iodine could play a role in biomarkers of insulin resistance and ß-cell activity. METHODS: We assessed the incidence of GDM between weeks 24 and 28 of gestation for 471 mother-neonate pairs from the ENVIRONAGE birth cohort. In placentas, we determined the iodine concentrations. In maternal and cord blood, we measured the insulin concentrations, the Homeostasis Model Assessment (HOMA) for insulin resistance (IR) index, and ß-cell activity. Logistic regression was used to estimate the odds ratios (OR) of GDM, and the population attributable factor (PAF) was calculated. Generalized linear models estimated the changes in insulin, HOMA-IR, and ß-cell activity for a 5 µg/kg increase in placental iodine. RESULTS: Higher placental iodine concentrations decreased the risk at GDM (OR = 0.82; 95%CI 0.72 to 0.93; p = 0.003). According to the PAF, 54.2% (95%CI 11.4 to 82.3%; p = 0.0006) of the GDM cases could be prevented if the mothers of the lowest tertile of placental iodine would have placental iodine levels as those belonging to the highest tertile. In cord blood, the plasma insulin concentration was inversely associated with the placental iodine load (ß = - 4.8%; 95%CI - 8.9 to - 0.6%; p = 0.026). CONCLUSIONS: Higher concentrations of placental iodine are linked with a lower incidence of GDM. Moreover, a lower placental iodine load is associated with an altered plasma insulin concentration, HOMA-IR index, and ß-cell activity. These findings postulate that a mild-to-moderate iodine deficiency could be linked with subclinical and early-onset alterations in the normal insulin homeostasis in healthy pregnant women. Nevertheless, the functional link between gestational iodine status and GDM warrants further research.

Bioenergetics adaptations and redox homeostasis in pregnancy and related disorders.

Pregnancy is a challenging physiological process that involves maternal adaptations to the increasing energetics demands imposed by the growing conceptus. Failure to adapt to these requirements may result in serious health complications for the mother and the baby. The mitochondria are biosynthetic and energy-producing organelles supporting the augmented energetic demands of pregnancy. Evidence suggests that placental mitochondria display a dynamic phenotype through gestation. At early stages of pregnancy placental mitochondria are mainly responsible for the generation of metabolic intermediates and reactive oxygen species (ROS), while at later stages of gestation, the placental mitochondria exhibit high rates of oxygen consumption. This review describes the metabolic fingerprint of the placental mitochondria at different stages of pregnancy and summarises key signs of mitochondrial dysfunction in pathological pregnancy conditions, including preeclampsia, gestational diabetes and intrauterine growth restriction (IUGR). So far, the effects of placental-driven metabolic changes governing the metabolic adaptations occurring in different maternal tissues in both, healthy and pathological pregnancies, remain to be uncovered. Understanding the function and molecular aspects of the adaptations occurring in placental and maternal tissue's mitochondria will unveil potential targets for further therapeutic exploration that could address pregnancy-related disorders. Targeting mitochondrial metabolism is an emerging approach for regulating mitochondrial bioenergetics. This review will also describe the potential therapeutic use of compounds with a recognised effect on mitochondria, for the management of preeclampsia.

Association of circulating omega 3, 6 and 9 fatty acids with gestational diabetes mellitus: a systematic review.

BACKGROUND: Gestational diabetes mellitus (GDM) is associated with increased risks of disease for mother and child during pregnancy and after that. Early diagnosis of GDM would promote both maternal and fetal health. Metabolomics can simplify and develop our understanding of the etiology, manifestation, or pathophysiology of the disease. This systematic review investigates the association of circulating omega 3, 6, and 9 fatty acids with GDM. METHODS: We conducted a systematic search of PubMed, Scopus, Web of Science, and EMBASE databases up to May 8, 2020, using the key term combinations of all types of omega fatty acids with gestational diabetes mellitus. Additional articles were identified through searching the reference lists of included studies. RESULTS: This systematic review included 15 articles. Five were cohort studies, four included nested case-control studies and four were case-control studies. The results of this study demonstrate an increasing trend in the amount of oleic acid and palmitoleic acid in the second trimester and an increase in decosahexanoic acid in the third trimester of GDM mothers. The changes in other fatty acids of interest are either not significant or if significant, their results are inconsistent with the other existing articles. CONCLUSIONS: Omega fatty acids, as potential biomarkers, are considered to be associated with GDM risk and thus provide useful information regarding the prevention and early diagnosis of GDM. Moreover, existing metabolomic studies on GDM are shown to provide conflicting results about metabolite profile characteristics. This systematic review was registered at PROSPERO ( www.crd.york.ac.uk/PROSPERO ) as CRD42020196122.

The role of Smad4 in the regulation of insulin resistance, inflammation and cell proliferation in HTR8-Svneo cells.

Gestational diabetes mellitus (GDM) is a metabolic disorder whose major pathophysiological basis is demonstrated as placental insulin resistance (IR), while Smad4 always functions in the signal transduction of transforming growth factor beta (TGF-ß) pathway. Our study aims to figure out the role of Smad4 in an insulin resistance (IR) cellular model using placental trophoblast cell line. Importantly, HTR8-Svneo cells, in the status of IR, indicated a significant increase in the expression of Smad4. Subsequently, the HTR8-Svneo cell line with up-regulated or depleted Smad4 was respectively achieved by the effective over-expressed plasmid or siRNA of Smad4. We found out that the deficiency of Smad4 could promote the insulin sensitivity and restrict the inflammatory response in IR group of cells with significant augment in glucose uptake, up-regulation of insulin signalling-related molecules and attenuation in inflammatory biomarker expressions. On the contrary, the over-expression of Smad4 showed a reversal effect on these alterations in IR group of cells. Besides, the positive effect of Smad4 on cell viability was also observed in our study. SIGNIFICANCE OF THE STUDY: Gestational diabetes mellitus (GDM) is a metabolic disorder whose major pathophysiological basis is demonstrated as insulin resistance (IR). Importantly, our findings indicate that the deficiency of Smad4 significantly improves the insulin sensitivity and relieves the inflammation in the cellular model of IR. Besides, the positive effect of Smad4 on cell viability was also observed in our study. Our present findings provide novel insights for the investigation on molecular details about the GDM pathogenesis.

Metabolic regulation and glucose sensitivity of cortical radial glial cells.

The primary stem cells of the cerebral cortex are the radial glial cells (RGCs), and disturbances in their operation lead to myriad brain disorders in all mammals from mice to humans. Here, we found in mice that maternal gestational obesity and hyperglycemia can impair the maturation of RGC fibers and delay cortical neurogenesis. To investigate potential mechanisms, we used optogenetic live-imaging approaches in embryonic cortical slices. We found that Ca2+ signaling regulates mitochondrial transport and is crucial for metabolic support in RGC fibers. Cyclic intracellular Ca2+ discharge from localized RGC fiber segments detains passing mitochondria and ensures their proper distribution and enrichment at specific sites such as endfeet. Impairment of mitochondrial function caused an acute loss of Ca2+ signaling, while hyperglycemia decreased Ca2+ activity and impaired mitochondrial transport, leading to degradation of the RGC scaffold. Our findings uncover a physiological mechanism indicating pathways by which gestational metabolic disturbances can interfere with brain development.

Epidemiology of Macrosomia in Korea: Growth and Development.

BACKGROUND: Macrosomia, as an infant with birth weight over 4 kg, can have several perinatal, and neonatal complications. This study aimed to estimate the incidence of macrosomia in Korea and to identify the growth and developmental outcomes and other neonatal complications. METHODS: In total, 397,203 infants who were born in 2013 with birth weight ≥ 2.5 kg and who underwent infant health check-up between their 1st and 7th visit were included from the National Health Insurance Service database. The information was obtained by the International Classification of Diseases-10 codes or self-reported questionnaires in the National Health Screening Program. RESULTS: The distribution of infants by birth weight was as follows: 384,181 (97%) infants in the 2.5-3.99 kg (reference) group, 12,016 (3%) infants in the 4.0-4.49 kg group, 772 (0.2%) infants in the 4.5-4.99 kg group, and 78 (0.02%) infants in the ≥ 5 kg group. Macrosomia showed significantly higher incidence of sepsis, male sex, and mothers with GDM and birth injury. There was a significant difference in weight, height, and head circumference according to age, birth weight group, and combination of age and birth weight, respectively (P < 0.001). The number of infants with the weight above the 90th percentile in macrosomia at each health check-up showed higher incidence than in reference group. The mean body mass index significantly differed among the groups, as 50.6 in infants with 2.5-3.99 kg of birth weight, 63.5 with 4.0-4.49 kg, 71.0 with 4.5-4.99 kg, and 73.1 with ≥ 5 kg. There was a significant difference in the incidence of poor developmental results between infants with macrosomia and the reference group at 24, 36 and 48 month of age. CONCLUSION: Macrosomia was significantly associated with the risk of sepsis, birth injury, obesity and developmental problem especially in a boy born from mothers with gestational diabetes mellitus. Careful monitoring and proper strategies for monitoring growth and development are needed.

Gestational Diabetes Mellitus and Maternal Immune Dysregulation: What We Know So Far.

Gestational diabetes mellitus (GDM) is an obstetric complication that affects approximately 5-10% of all pregnancies worldwide. GDM is defined as any degree of glucose intolerance with onset or first recognition during pregnancy, and is characterized by exaggerated insulin resistance, a condition which is already pronounced in healthy pregnancies. Maternal hyperglycaemia ensues, instigating a 'glucose stress' response and concurrent systemic inflammation. Previous findings have proposed that both placental and visceral adipose tissue play a part in instigating and mediating this low-grade inflammatory response which involves altered infiltration, differentiation and activation of maternal innate and adaptive immune cells. The resulting maternal immune dysregulation is responsible for exacerbation of the condition and a further reduction in maternal insulin sensitivity. GDM pathology results in maternal and foetal adverse outcomes such as increased susceptibility to diabetes mellitus development and foetal neurological conditions. A clearer understanding of how these pathways originate and evolve will improve therapeutic targeting. In this review, we will explore the existing findings describing maternal immunological adaption in GDM in an attempt to highlight our current understanding of GDM-mediated immune dysregulation and identify areas where further research is required.

Effect of Endogenic and Exogenic Oxidative Stress Triggers on Adverse Pregnancy Outcomes: Preeclampsia, Fetal Growth Restriction, Gestational Diabetes Mellitus and Preterm Birth.

Oxidative stress is caused by an imbalance between the production of reactive oxygen species (ROS) in cells and tissues and the ability of a biological system to detoxify them. During a normal pregnancy, oxidative stress increases the normal systemic inflammatory response and is usually well-controlled by the balanced body mechanism of the detoxification of anti-oxidative products. However, pregnancy is also a condition in which this adaptation and balance can be easily disrupted. Excessive ROS is detrimental and associated with many pregnancy complications, such as preeclampsia (PE), fetal growth restriction (FGR), gestational diabetes mellitus (GDM), and preterm birth (PTB), by damaging placentation. The placenta is a tissue rich in mitochondria that produces the majority of ROS, so it is important to maintain normal placental function and properly develop its vascular network to ensure a safe and healthy pregnancy. Antioxidants may ameliorate these diseases, and related research is progressing. This review aimed to determine the association between oxidative stress and adverse pregnancy outcomes, especially PE, FGR, GDM, and PTB, and explore how to overcome this oxidative stress in these unfavorable conditions.

Novel Biomolecules in the Pathogenesis of Gestational Diabetes Mellitus.

Gestational diabetes mellitus (GDM) is one of the most common metabolic diseases in pregnant women. Its early diagnosis seems to have a significant impact on the developing fetus, the course of delivery, and the neonatal period. It may also affect the later stages of child development and subsequent complications in the mother. Therefore, the crux of the matter is to find a biopredictor capable of singling out women at risk of developing GDM as early as the very start of pregnancy. Apart from the well-known molecules with a proven and clear-cut role in the pathogenesis of GDM, e.g., adiponectin and leptin, a potential role of newer biomolecules is also emphasized. Less popular and less known factors with different mechanisms of action include: galectins, growth differentiation factor-15, chemerin, omentin-1, osteocalcin, resistin, visfatin, vaspin, irisin, apelin, fatty acid-binding protein 4 (FABP4), fibroblast growth factor 21, and lipocalin-2. The aim of this review is to present the potential and significance of these 13 less known biomolecules in the pathogenesis of GDM. It seems that high levels of FABP4, low levels of irisin, and high levels of under-carboxylated osteocalcin in the serum of pregnant women can be used as predictive markers in the diagnosis of GDM. Hopefully, future clinical trials will be able to determine which biomolecules have the most potential to predict GDM.

Epigenetic Changes in Gestational Diabetes Mellitus.

Gestational diabetes mellitus (GDM) is defined as carbohydrate intolerance that appears or is for the first time diagnosed during pregnancy. It can lead to many complications in the mother and in the offspring, so diagnostics and management of GDM are important to avoid adverse pregnancy outcomes. Epigenetic studies revealed the different methylation status of genes in pregnancies with GDM compared to pregnancies without GDM. A growing body of evidence shows that the GDM can affect not only the course of the pregnancy, but also the development of the offspring, thus contributing to long-term effects and adverse health outcomes of the progeny. Epigenetic changes occur through histone modification, DNA methylation, and disrupted function of non-coding ribonucleic acid (ncRNA) including microRNAs (miRNAs). In this review, we focus on the recent knowledge about epigenetic changes in GDM. The analysis of this topic may help us to understand pathophysiological mechanisms in GDM and find a solution to prevent their consequences.

Lipid Metabolism Is Dysregulated before, during and after Pregnancy in a Mouse Model of Gestational Diabetes.

The aim of the current study was to test the hypothesis that maternal lipid metabolism was modulated during normal pregnancy and that these modulations are altered in gestational diabetes mellitus (GDM). We tested this hypothesis using an established mouse model of diet-induced obesity with pregnancy-associated loss of glucose tolerance and a novel lipid analysis tool, Lipid Traffic Analysis, that uses the temporal distribution of lipids to identify differences in the control of lipid metabolism through a time course. Our results suggest that the start of pregnancy is associated with several changes in lipid metabolism, including fewer variables associated with de novo lipogenesis and fewer PUFA-containing lipids in the circulation. Several of the changes in lipid metabolism in healthy pregnancies were less apparent or occurred later in dams who developed GDM. Some changes in maternal lipid metabolism in the obese-GDM group were so late as to only occur as the control dams' systems began to switch back towards the non-pregnant state. These results demonstrate that lipid metabolism is modulated in healthy pregnancy and the timing of these changes is altered in GDM pregnancies. These findings raise important questions about how lipid metabolism contributes to changes in metabolism during healthy pregnancies. Furthermore, as alterations in the lipidome are present before the loss of glucose tolerance, they could contribute to the development of GDM mechanistically.