Insulin Therapy for Gestational Diabetes Mellitus Does Not Fully Protect Offspring From Diet-Induced Metabolic Disorders

Intrauterine hyperglycemia induces SIRT3-mediated mitochondrial dysfunction: the fetal origin pathogenesis of precocious osteoarthritis

OBJECTIVE

Diabetes and other metabolic and inflammatory comorbidities are highly associated with osteoarthritis (OA). However, whether early-life hyperglycemia exposure affects susceptibility to long-term OA is still unknown. The purpose of this study was to explore the fetal origins of OA and provide insights into early-life safeguarding for individual health.

METHOD

This study utilized streptozotocin to induce intrauterine hyperglycemia and performed destabilization of the medial meniscus surgery on the knee joints of the offspring mice to induce accelerated OA. Cartilage degeneration-related markers, as well as the expression levels of mitochondrial respiratory chain complexes and mitophagy genes in the adult offspring mice, were investigated. In vitro, mitochondrial function and mitophagy of chondrocyte C28/I2 cells stimulated under high glucose conditions were also evaluated. The methylation levels of the sirt3 gene promoter region in the articular cartilage of intrauterine hyperglycemia-exposed offspring mice were further analyzed.

RESULTS

In this study, we found that the intrauterine hyperglycemic environment could lead to an increase in individual susceptibility to OA in late adulthood, mainly due to persistently low levels of Sirt3 expression. Downregulation of Sirt3 causes impaired mitophagy in chondrocytes and abnormal mitochondrial respiratory function due to a failure to clear aged and damaged mitochondria in a timely manner. Overexpressing Sirt3 at the cellular level or using Sirt3 agonists like Honokiol in mouse models can partially rescue mitophagy disorders caused by the hyperglycemic environment and thus alleviate the progression of OA.

CONCLUSION

Our study revealed a significantly increased susceptibility to OA in the gestational diabetes mellitus offspring, which is partly attributed to exposure to adverse factors in utero and ultimately to the onset of disease via epigenetic modulation.

The role of machine learning algorithms in detection of gestational diabetes; a narrative review of current evidence

Gestational Diabetes Mellitus (GDM) poses significant health risks to mothers and infants. Early prediction and effective management are crucial to improving outcomes. Machine learning techniques have emerged as powerful tools for GDM prediction. This review compiles and analyses the available studies to highlight key findings and trends in the application of machine learning for GDM prediction. A comprehensive search of relevant studies published between 2000 and September 2023 was conducted. Fourteen studies were selected based on their focus on machine learning for GDM prediction. These studies were subjected to rigorous analysis to identify common themes and trends. The review revealed several key themes. Models capable of predicting GDM risk during the early stages of pregnancy were identified from the studies reviewed. Several studies underscored the necessity of tailoring predictive models to specific populations and demographic groups. These findings highlighted the limitations of uniform guidelines for diverse populations. Moreover, studies emphasised the value of integrating clinical data into GDM prediction models. This integration improved the treatment and care delivery for individuals diagnosed with GDM. While different machine learning models showed promise, selecting and weighing variables remains complex. The reviewed studies offer valuable insights into the complexities and potential solutions in GDM prediction using machine learning. The pursuit of accurate, early prediction models, the consideration of diverse populations, clinical data, and emerging data sources underscore the commitment of researchers to improve healthcare outcomes for pregnant individuals at risk of GDM.

Pre-eclamptic foetal programming predisposes offspring to hepatic steatosis via DNA methylation

OBJECTIVES

Gamete and embryo-foetal origins of adult diseases hypothesis proposes that adulthood chronic disorders are associated with adverse foetal and early life traits. Our study aimed to characterise developmental changes and underlying mechanisms of metabolic disorders in offspring of pre-eclampsia (PE) programmed pregnancy.

METHODS

Nω-Nitro-l-arginine methyl ester hydrochloride (L-NAME) induced pre-eclampsia-like C57BL/6J mouse model was used. Lipid profiling, histological morphology, indirect calorimetry, mRNA sequencing, and pyrosequencing were performed on PE offspring of both young and elderly ages.

RESULTS

PE offspring exhibited increased postnatal weight gain, hepatic lipid accumulation, enlarged adipocytes, and impaired energy balance that continued to adulthood. Integrated RNA sequencing of foetal and 52-week-old livers revealed that the differentially expressed genes were mainly enriched in lipid metabolism, including glycerol-3-phosphate acyl-transferase 3 (Gpat3), a key enzyme for de novo synthesis of triglycerides (TG), and carnitine palmitoyltransferase-1a (Cpt1a), a key transmembrane enzyme that mediates fatty acid degradation. Pyrosequencing of livers from PE offspring identified hypomethylated and hypermethylated regions in Gpat3 and Cpt1a promoters, which were associated with upregulated and downregulated expressions of Gpat3 and Cpt1a, respectively. These epigenetic alterations are persistent and consistent from the foetal stage to adulthood in PE offspring.

CONCLUSION

These findings suggest a methylation-mediated epigenetic mechanism for PE-induced intergenerational lipid accumulation, impaired energy balance and obesity in offspring, and indicate the potential benefits of early interventions in offspring exposed to maternal PE to reduce their susceptibility to metabolic disorder in their later life.

Cerium Oxide Nanozymes Improve Skeletal Muscle Function in Gestational Diabetic Offspring by Attenuating Mitochondrial Oxidative Stress

Gestational diabetes mellitus (GDM) is a significant complication during pregnancy that results in abnormalities in the function of multiple systems in the offspring, which include skeletal muscle dysfunction and reduced systemic metabolic capacity. One of the primary causes behind this intergenerational effect is the presence of mitochondrial dysfunction and oxidative stress in the skeletal muscle of the offspring due to exposure to a high-glucose environment in utero. Cerium oxide (CeO2) nanozymes are antioxidant agents with polymerase activity that have been widely used in the treatment of inflammatory and aging diseases. In this study, we synthesized ultrasmall particle size CeO2 nanozymes and applied them in GDM mouse offspring. The CeO2 nanozymes demonstrated an ability to increase insulin sensitivity and enhance skeletal muscle motility in GDM offspring by improving mitochondrial activity, increasing mitochondrial ATP synthesis function, and restoring abnormal mitochondrial morphology. Furthermore, at the cellular level, CeO2 nanozymes could ameliorate metabolic dysregulation and decrease cell differentiation in adult muscle cells induced by hyperglycemic stimuli. This was achieved through the elimination of endogenous reactive oxygen species (ROS) and an improvement in mitochondrial oxidative respiration function. In conclusion, CeO2 nanozymes play a crucial role in preserving muscle function and maintaining the metabolic stability of organisms. Consequently, they serve to reverse the negative effects of GDM on skeletal muscle physiology in the offspring.

Maternal Brown Rice Diet during Pregnancy Promotes Adipose Tissue Browning in Offspring via Reprogramming PKA Signaling and DNA Methylation

SCOPE

Brown rice, the most consumed food worldwide, has been shown to possess beneficial effects on the prevention of metabolic diseases. However, the way in which maternal brown rice diet improves metabolism in offspring and the regulatory mechanisms remains unclear. The study explores the epigenetic regulation of offspring energy metabolic homeostasis by maternal brown rice diet during pregnancy.

METHODS AND RESULTS

Female mice are fed brown rice during pregnancy, and then body phenotypes, the histopathological analysis, and adipose tissues biochemistry assay of offspring mice are detected. It is found that maternal brown rice diet significantly reduces body weight and fat mass, increases energy expenditure and heat production in offspring. Maternal brown rice diet increases uncoupling protein 1 (UCP1) protein level and upregulates the mRNA expression of thermogenic genes in adipose tissues. Mechanistically, protein kinase A (PKA) signaling is likely responsible in the induced thermogenic program in offspring adipocytes, and the progeny adipocytes browning program is altered due to decreased level of DNA methyltransferase 1 protein and hypomethylation of the transcriptional coregulator positive regulatory domain containing 16 (PRDM16).

CONCLUSIONS

These findings demonstrate that maternal brown rice during pregnancy improves offspring mice metabolic homeostasis via promoting adipose browning, and its mechanisms may be mediated by DNA methylation reprogramming.

Polysaccharides (pectin, mucilage, and fructan inulin) and their fermented products: A critical analysis of their biochemical, gut interactions, and biological functions as antidiabetic agents

Diabetes mellitus is a globally metabolic endocrine syndrome marked by a deficiency of insulin secretion (type-1 DM) or glucose intolerance arising from insulin response impairment (type-2 DM) leading to abnormal glucose metabolism. With an increasing interest in natural dietary components for diabetes management, the identification of novel agents witnessed major discoveries. Plant-derived mucilage, pectin, and inulin are important non-starch polysaccharides that exhibit effective antidiabetic properties often termed soluble dietary fiber (SDF). SDF affects sugar metabolism through multiple mechanisms affecting glucose absorption and diffusion, modulation of carbohydrate metabolizing enzymes (α-amylase and α-glucosidase), ameliorating β-pancreatic cell dysfunction, and improving insulin release or sensitivity. Certain SDFs inhibit dipeptidyl peptidase-4 and influence the expression levels of genes related to glucose metabolism. This review is designed to discuss holistically and critically the antidiabetic effects of major SDF and their underlying mechanisms of action. This review should aid drug discovery approaches in developing novel natural antidiabetic drugs from SDF.

LncRNA HCP5 is Highly Expressed in Gestational Diabetes Mellitus to Suppress Insulin Secretion

Purpose

LncRNA HCP5 has been reported to participate in high glucose-induced pathological processes, whereas its role in gestational diabetes mellitus (GDM) is unclear. This study aimed to explore the role of HCP5 in GDM.

Methods

This study enrolled a total of 220 pregnant women (gestational age = 1 month). A follow-up study was performed until delivery. The occurrence of GDM was checked every month during follow-up. Plasma samples were collected from all participants and expression of HCP5 was determined with RT-qPCR. The 220 patients were divided into high and low GDM groups, and GDM-free curves were plotted for both groups and compared. The ROC curve was plotted to explore the predictive value of plasma HCP5 on the day of admission for GDM. INS-1 cells were transfected with HCP5 expression vector or siRNA, and cell viability under high glucose was determined by the MTT assay. An ELISA was applied to determine insulin levels in the cell culture medium.

Results

During follow-up, the level of HCP5 was increased during pregnancy and the high HCP5 level group showed a significantly higher incidence of GDM. Plasma levels of HCP5 on the day of admission effectively separated GDM patients from healthy controls. HCP5 negatively regulated cell viability and insulin secretion under high glucose treatment.

Conclusion

HCP5 may act as a predictor for GDM, and it negatively regulated INS-1 cell viability and insulin secretion under high glucose conditions.

Maternal inulin alleviates high-fat diet-induced lipid disorder in offspring by epigenetically modulating hypothalamus feeding circuit-related genes

Increasing evidence supports the existence of fetal-originated adult diseases. Recent research indicates that the intrauterine environment affects the fetal hypothalamic energy intake center. Inulin is a probiotic that can moderate metabolic disorders, but whether maternal inulin intervention confers long-term metabolic benefits to lipid metabolism in offspring in their adult lives and the mechanism involved are unknown. Here, we used a maternal overnutrition model that was induced by excess energy intake before and during pregnancy and lactation and maternal inulin intervention was performed during pregnancy and lactation. The hypothalamic genome methylation in offspring was analyzed using a methylation array. The results showed that maternal inulin treatment modified the maternal high-fat diet (HFD)-induced increases in body weight, adipose tissue weight, and serum insulin and leptin levels and decreases in serum adiponectin levels. Maternal inulin intervention regulated the impairments in hypothalamic leptin resistance, induced the methylation of Socs3, Npy, and Il6, and inhibited the methylation of Lepr in the hypothalamus of offspring. In conclusion, maternal inulin intervention modifies offspring lipid metabolism, and the underlying mechanism involves the methylation of genes in the hypothalamus feeding circuit.

Altered expression of long noncoding RNA MEG3 in the offspring of gestational diabetes mellitus induces impaired glucose tolerance in adulthood

AIM

Gestational diabetes mellitus (GDM) affects a significant number of women worldwide and has been associated with lifelong health consequences for their offspring, including increased susceptibility to obesity, insulin resistance, and type II diabetes. Recent studies have suggested that aberrant expression of the long non-coding RNA Meg3 in the liver may contribute to impaired glucose metabolism in individuals. In this study, we aimed to investigate whether intrauterine exposure to hyperglycemia affects glucose intolerance in puberty by mediating the overexpression of LncMeg3 in the liver.

METHODS

To test our hypothesis, we established an animal model of intrauterine hyperglycemia to mimic GDM. The progeny was observed for phenotypic changes, and intraperitoneal glucose tolerance tests, insulin tolerance tests, and pyruvate tolerance tests were conducted to assess glucose and insulin tolerance. We also measured LncMeg3 expression in the liver using real-time quantitative PCR and examined differential methylation areas (DMRs) in the Meg3 gene using pyrophosphoric sequencing. To investigate the role of LncMeg3 in glucose tolerance, we conducted Meg3 intervention by vein tail and analyzed the changes in the phenotype and transcriptome of the progeny using bioinformatics analysis.

RESULTS

We found that intrauterine exposure to hyperglycemia led to impaired glucose and insulin tolerance in the progeny, with a tendency toward increased fasting blood glucose in fat offspring at 16 weeks (P = 0.0004). LncMeg3 expression was significantly upregulated (P = 0.0061), DNMT3B expression downregulated (P = 0.0226), and DNMT3A (P = 0.0026), TET2 (P = 0.0180) expression upregulated in the liver. Pyrophosphoric sequencing showed hypomethylation in Meg3-DMRs (P = 0.0005). Meg3 intervention by vein tail led to a decrease in the percentage of obese and emaciated offspring (emaciation: 44% vs. 23%; obesity: 25% vs. 15%) and attenuated glucose intolerance. Bioinformatics analysis revealed significant differences in the transcriptome of the progeny, particularly in circadian rhythm and PPAR signaling pathways.

CONCLUSION

In conclusion, our study suggests that hypomethylation of Meg3-DMRs increases the expression of the imprinted gene Meg3 in the liver of males, which is associated with impaired glucose tolerance in GDM-F1. MEG3 interference may attenuate glucose intolerance, which may be related to transcriptional changes. Our findings provide new insights into the mechanisms underlying the long-term effects of intrauterine hyperglycemia on progeny health and highlight the potential of Meg3 as an intervention target for glucose intolerance.

The yield of early-pregnancy homeostasis of model assessment -insulin resistance (HOMA-IR) for predicting gestational diabetes mellitus in different body mass index and age groups

BACKGROUND

Early prediction of gestational diabetes mellitus(GDM) can be beneficial for lifestyle modifications to prevent GDM. The aim of this study was to investigate the predictive values of Homeostasis of Model Assessment -Insulin Resistance (HOMA-IR) in early pregnancy to predict GDM development in different body mass index (BMI) and age risk categories.

MATERIALS AND METHODS

This study is part of the Qazvin Maternal and Neonatal Metabolic Study (QMNMS) in Iran (2018-2021). In this prospective longitudinal study, pregnant women with a gestational age ≤ 14 weeks were enrolled in the study using convenience sampling method and were followed up until delivery to investigate risk factors for maternal and neonatal complications. Data collection was done using questionnaires. Serum sampling was done at a gestational age ≤ 14 weeks and sera were frozen until the end of study. GDM was diagnosed at 24-28 weeks of pregnancy using 75gr oral glucose tolerance test. Fasting blood glucose and insulin were measured in sera taken during early pregnancy in 583 participants. The Mann-Whitney U test, independent t-test, and Chi-square test were used for comparing variables between groups. The logistic regression analysis was used to examine the independent association of HOMA-IR with GDM development and receiver operating characteristic analysis was used for finding the best cut-off of HOMA-IR for predicting GDM.

RESULTS

GDM was developed in 90 (15.4%) of the participants. The third HOMA-IR tertile was independently associated with 3.2 times higher GDM occurrence (95% CI:1.6-6.2, P = 0.001). Despite the high prevalence of GDM in advanced maternal age (GDM rate = 28.4%), HOMA-IR had no association with GDM occurrence in this high-risk group. In both normal BMI and overweight/obese groups, HOMA-IR was a moderate predictor of GDM development (AUC = 0.638, P = 0.005 and AUC = 0.622, P = 0.008, respectively). However, the best cut-off for predicting GDM was 2.06 (sensitivity 67.5%, specificity 61.1%) in normal BMI and 3.13 (sensitivity 64.6%, specificity61.8%) in overweight/obese BMI.

CONCLUSION

The present study revealed the necessity of considering the BMI and age risk groups when using the HOMA-IR index to predict GDM. Using lower cut-offs is more accurate for women with a normal BMI. In the advanced maternal age, there is no yield of HOMA-IR for predicting GDM.

Genetic and Epigenetic Factors in Gestational Diabetes Mellitus Pathology

Gestational diabetes (GDM) is the carbohydrate intolerance occurring during pregnancy. The risk factors of GDM include obesity, advanced maternal age, polycystic ovary syndrome, multigravidity, a sedentary lifestyle, and pre-existing hypertension. Additionally, complex genetic and epigenetic processes are also believed to play a crucial role in the development of GDM. In this narrative review, we discuss the role of genetic and epigenetic factors in gestational diabetes mellitus pathogenesis.

The Role of Gut Microbiota in Gestational Diabetes Mellitus Affecting Intergenerational Glucose Metabolism: Possible Mechanisms and Interventions

The incidence of type 2 diabetes is increasing every year and has become a serious public health problem. In addition to genetic factors, environmental factors in early life development are risk factors for diabetes. There is growing evidence that the gut microbiota plays an important role in glucose metabolism, and the gut microbiota of pregnant women with gestational diabetes mellitus (GDM) differs significantly from that of healthy pregnant women. This article reviews the role of maternal gut microbiota in offspring glucose metabolism. To explore the potential mechanisms by which the gut microbiota affects glucose metabolism in offspring, we summarize clinical studies and experimental animal models that support the hypothesis that the gut microbiota affects glucose metabolism in offspring from dams with GDM and discuss interventions that could improve glucose metabolism in offspring. Given that adverse pregnancy outcomes severely impact the quality of survival, reversing the deleterious effects of abnormal glucose metabolism in offspring through early intervention is important for both mothers and their offspring.

Integration of clinical demographics and routine laboratory analysis parameters for early prediction of gestational diabetes mellitus in the Chinese population

Gestational diabetes mellitus (GDM) is one of the most common complications in pregnancy, impairing both maternal and fetal health in short and long term. As early interventions are considered desirable to prevent GDM, this study aims to develop a simple-to-use nomogram based on multiple common risk factors from electronic medical health records (EMHRs). A total of 924 pregnant women whose EMHRs were available at Peking University International Hospital from January 2022 to October 2022 were included. Clinical demographics and routine laboratory analysis parameters at 8-12 weeks of gestation were collected. A novel nomogram was established based on the outcomes of multivariate logistic regression. The nomogram demonstrated powerful discrimination (the area under the receiver operating characteristic curve = 0.7542), acceptable agreement (Hosmer-Lemeshow test, P = 0.3214) and favorable clinical utility. The C-statistics of 10-Fold cross validation, Leave one out cross validation and Bootstrap were 0.7411, 0.7357 and 0.7318, respectively, indicating the stability of the nomogram. A novel nomogram based on easily-accessible parameters was developed to predict GDM in early pregnancy, which may provide a paradigm for repurposing clinical data and benefit the clinical management of GDM. There is a need for prospective multi-center studies to validate the nomogram before employing the nomogram in real-world clinical practice.

Long-term outcomes and potential mechanisms of offspring exposed to intrauterine hyperglycemia

Diabetes mellitus during pregnancy, which can be classified into pregestational diabetes and gestational diabetes, has become much more prevalent worldwide. Maternal diabetes fosters an intrauterine abnormal environment for fetus, which not only influences pregnancy outcomes, but also leads to fetal anomaly and development of diseases in later life, such as metabolic and cardiovascular diseases, neuropsychiatric outcomes, reproduction malformation, and immune dysfunction. The underlying mechanisms are comprehensive and ambiguous, which mainly focus on microbiota, inflammation, reactive oxygen species, cell viability, and epigenetics. This review concluded with the influence of intrauterine hyperglycemia on fetal structure development and organ function on later life and outlined potential mechanisms that underpin the development of diseases in adulthood. Maternal diabetes leaves an effect that continues generations after generations through gametes, thus more attention should be paid to the prevention and treatment of diabetes to rescue the pathological attacks of maternal diabetes from the offspring.

Sex differences in glycolipidic disorders after exposure to maternal hyperglycemia during early development

PURPOSE

The aim of this review was to summarize sex differences in glycolipid metabolic phenotypes of human and animal models after exposure to maternal hyperglycemia and overview the underlying mechanisms, providing a new perspective on the maternal hyperglycemia-triggered risk of glycolipidic disorders in offspring.

METHODS

A comprehensive literature search within PubMed was performed. Selected publications related to studies on offspring exposed to maternal hyperglycemia investigating the sex differences of glycolipid metabolism were reviewed.

RESULTS

Maternal hyperglycemia increases the risk of glycolipid metabolic disorders in offspring, such as obesity, glucose intolerance and diabetes. Whether with or without intervention, metabolic phenotypes have been shown to exhibit sex differences between male and female offspring in response to maternal hyperglycemia, which may be related to gonadal hormones, organic intrinsic differences, placenta, and epigenetic modifications.

CONCLUSION

Sex may play a role in the different incidences and pathogenesis of abnormal glycolipid metabolism. More studies investigating both sexes are needed to understand how and why environmental conditions in early life affect long-term health between male and female individuals.

Maternal secretin ameliorates obesity by promoting white adipose tissue browning in offspring

Our knowledge of the coordination of intergenerational inheritance and offspring metabolic reprogramming by gastrointestinal endocrine factors is largely unknown. Here, we showed that secretin (SCT), a brain-gut peptide, is downregulated by overnutrition in pregnant mice and women. More importantly, genetic loss of SCT in the maternal gut results in undesirable phenotypes developed in offspring including enhanced high-fat diet (HFD)-induced obesity and attenuated browning of inguinal white adipose tissue (iWAT). Mechanistically, loss of maternal SCT represses iWAT browning in offspring by a global change in genome methylation pattern through upregulation of DNMT1. SCT functions to facilitate ubiquitination and degradation of DNMT1 by activating AMPKα, which contributes to the observed alteration of DNMT1 in progeny. Lastly, we showed that SCT treatment during pregnancy can reduce the development of obesity and improve glucose tolerance and insulin resistance in offspring of HFD-fed females, suggesting that SCT may serve as a novel biomarker or a strategy for preventing metabolic diseases.

Gestational diabetes mellitus suppresses fetal testis development in mice

The prevalence of Gestational diabetes mellitus (GDM) is increasing rapidly. In addition to the metabolic disease risks, GDM might increase the risks of cryptorchidism in children. However, its mechanism involved in abnormalities of the male reproductive system is still unclear. The purpose of this study was to study the effects of GDM on the development of mouse fetal Leydig and Sertoli cells. Pregnant mice were treated on gestational day (GD) 6.5 and 12.5 with streptozotocin (STZ, 100 mg/kg) or vehicle (sodium citrate buffer). Leydig and Sertoli cell development and functions were evaluated by investigating serum testosterone levels, cell number and distribution, genes, and protein expression. GDM decreased serum testosterone levels, the anogenital distance, and the level of DHH in Sertoli cells of testes of male offspring. Fetal Leydig cell number was also decreased in testes of GDM offspring by delaying the commitment of stem Leydig cells into the Leydig cell lineage. RNA-seq showed that FOXL2, RSPO1/β-Catenin signaling was activated and Gsk3β signaling was inhibited in GDM offspring testis. In conclusion, GDM disrupted reproductive tract and testis development in mouse male offspring via altering genes related to development.

Maternal inheritance of glucose intolerance via oocyte TET3 insufficiency

Diabetes mellitus is prevalent among women of reproductive age, and many women are left undiagnosed or untreated¹. Gestational diabetes has profound and enduring effects on the long-term health of the offspring^2,3. However, the link between pregestational diabetes and disease risk into adulthood in the next generation has not been sufficiently investigated. Here we show that pregestational hyperglycaemia renders the offspring more vulnerable to glucose intolerance. The expression of TET3 dioxygenase, responsible for 5-methylcytosine oxidation and DNA demethylation in the zygote⁴, is reduced in oocytes from a mouse model of hyperglycaemia (HG mice) and humans with diabetes. Insufficient demethylation by oocyte TET3 contributes to hypermethylation at the paternal alleles of several insulin secretion genes, including the glucokinase gene (Gck), that persists from zygote to adult, promoting impaired glucose homeostasis largely owing to the defect in glucose-stimulated insulin secretion. Consistent with these findings, mouse progenies derived from the oocytes of maternal heterozygous and homozygous Tet3 deletion display glucose intolerance and epigenetic abnormalities similar to those from the oocytes of HG mice. Moreover, the expression of exogenous Tet3 mRNA in oocytes from HG mice ameliorates the maternal effect in offspring. Thus, our observations suggest an environment-sensitive window in oocyte development that confers predisposition to glucose intolerance in the next generation through TET3 insufficiency rather than through a direct perturbation of the oocyte epigenome. This finding suggests a potential benefit of pre-conception interventions in mothers to protect the health of offspring.

Integrated Multi-Omics Analysis Reveals the Effect of Maternal Gestational Diabetes on Fetal Mouse Hippocampi

Growing evidence suggests that adverse intrauterine environments could affect the long-term health of offspring. Recent evidence indicates that gestational diabetes mellitus (GDM) is associated with neurocognitive changes in offspring. However, the mechanism remains unclear. Using a GDM mouse model, we collected hippocampi, the structure critical to cognitive processes, for electron microscopy, methylome and transcriptome analyses. Reduced representation bisulfite sequencing (RRBS) and RNA-seq in the GDM fetal hippocampi showed altered methylated modification and differentially expressed genes enriched in common pathways involved in neural synapse organization and signal transmission. We further collected fetal mice brains for metabolome analysis and found that in GDM fetal brains, the metabolites displayed significant changes, in addition to directly inducing cognitive dysfunction, some of which are important to methylation status such as betaine, fumaric acid, L-methionine, succinic acid, 5-methyltetrahydrofolic acid, and S-adenosylmethionine (SAM). These results suggest that GDM affects metabolites in fetal mice brains and further affects hippocampal DNA methylation and gene regulation involved in cognition, which is a potential mechanism for the adverse neurocognitive effects of GDM in offspring.

The intestine and the microbiota in maternal glucose homeostasis during pregnancy

It is now well established that, beyond its role in nutrient processing and absorption, the intestine and its accompanying gut microbiome constitute a major site of immunological and endocrine regulation that mediates whole-body metabolism. Despite the growing field of host-microbe research, few studies explore what mechanisms govern this relationship in the context of pregnancy. During pregnancy, significant maternal metabolic adaptations are made to accommodate the additional energy demands of the developing fetus and to prevent adverse pregnancy outcomes. Recent data suggest that the maternal gut microbiota may play a role in these adaptations, but changes to maternal gut physiology and the underlying intestinal mechanisms remain unclear. In this review, we discuss selective aspects of intestinal physiology including the role of the incretin hormone, glucagon-like peptide 1 (GLP-1), and the role of the maternal gut microbiome in the maternal metabolic adaptations to pregnancy. Specifically, we discuss how bacterial components and metabolites could mediate the effects of the microbiota on host physiology, including nutrient absorption and GLP-1 secretion and action, and whether these mechanisms may change maternal insulin sensitivity and secretion during pregnancy. Finally, we discuss how these pathways could be altered in disease states during pregnancy including maternal obesity and diabetes.

The mitochondrial-derived peptide MOTS-c relieves hyperglycemia and insulin resistance in gestational diabetes mellitus

The most common complication during pregnancy, gestational diabetes mellitus (GDM), can cause adverse pregnancy outcomes and result in the mother and infant having a higher risk of developing type 2 diabetes after pregnancy. However, existing therapies for GDM remain scant, with the most common being lifestyle intervention and appropriate insulin treatment. MOTS-c, a mitochondrial-derived peptide, can target skeletal muscle and enhance glucose metabolism. Here, we demonstrate that MOTS-c can be an effective treatment for GDM. A GDM mouse model was established by short term high-fat diet combined with low-dose streptozotocin (STZ) treatment while MOTS-c was administrated daily during pregnancy. GDM symptoms such as blood glucose and insulin levels, glucose and insulin tolerance, as well as reproductive outcomes were investigated. MOTS-c significantly alleviated hyperglycemia, improved insulin sensitivity and glucose tolerance, and reduced birth weight and the death of offspring induced by GDM. Similar to a previous study, MOTS-c also could activate insulin sensitivity in the skeletal muscle of GDM mice and elevate glucose uptake in vitro. In addition, we found that MOTS-c protects pancreatic β-cell from STZ-mediated injury. Taken together, our findings demonstrate that MOTS-c could be a promising strategy for the treatment of GDM.

Hepatic IGF2/H19 Epigenetic Alteration Induced Glucose Intolerance in Gestational Diabetes Mellitus Offspring via FoxO1 Mediation

OBJECTIVE

The offspring of women with gestational diabetes mellitus (GDM) have a high predisposition to developing type 2 diabetes during childhood and adulthood. The aim of the study was to evaluate how GDM exposure in the second half of pregnancy contributes to hepatic glucose intolerance through a mouse model.

METHODS

By creating a GDM mouse model, we tested glucose and insulin tolerance of offspring by intraperitoneal glucose tolerance test (IPGTT), insulin tolerance test (ITT), and pyruvate tolerance test (PTT). In addition, we checked the expression of genes IGF2/H19, FoxO1, and DNMTs in the mouse liver by RT-qPCR. Pyrosequencing was used to detect the methylation status on IGF2/H19 differentially methylated regions (DMRs). In vitro insulin stimulation experiments were performed to evaluate the effect of different insulin concentrations on HepG2 cells. Moreover, we detect the interaction between FoxO1 and DNMT3A by chromatin immunoprecipitation-quantitative PCR (Chip-qPCR) and knock-down experiments on HepG2 cells.

RESULTS

We found that the first generation of GDM offspring (GDM-F1) exhibited impaired glucose tolerance (IGT) and insulin resistance, with males being disproportionately affected. In addition, the expression of imprinted genes IGF2 and H19 was downregulated in the livers of male mice via hypermethylation of IGF2-DMR0 and IGF2-DMR1. Furthermore, increased expression of transcriptional factor FoxO1 was confirmed to regulate DNMT3A expression, which contributed to abnormal methylation of IGF2/H19 DMRs. Notably, different insulin treatments on HepG2 demonstrated those genetic alterations, suggesting that they might be induced by intrauterine hyperinsulinemia.

CONCLUSION

Our results demonstrated that the intrauterine hyperinsulinemia environment has increased hepatic FoxO1 levels and subsequently increased expression of DNMT3A and epigenetic alterations on IGF2/H19 DMRs. These findings provide potential molecular mechanisms responsible for glucose intolerance and insulin resistance in the first male generation of GDM mice.

High Maternal Serum Estradiol in First Trimester of Multiple Pregnancy Contributes to Small for Gestational Age via DNMT1-Mediated CDKN1C Upregulation

High maternal serum estradiol (E₂) levels in the first trimester of pregnancy are associated with a high incidence of low birth weight (LBW) and small for gestational age (SGA). This study aimed to investigate the effect of first-trimester high maternal serum E₂ levels on fetal growth and the underlying mechanisms in multiple pregnancies. Maternal serum E₂ levels of women at 8 weeks of gestation were measured. The expression levels of imprinted genes and DNMT1 were determined by RT-qPCR, and KvDMR1 methylation in embryo tissue, placenta, and newborn cord blood samples was examined by bisulfite sequencing PCR. The effect of E₂ on CDKN1C expression was investigated in HTR8 cells. The incidence of SGA was significantly higher in multiple pregnancies reduced to singleton than that in primary singleton pregnancies (11.4% vs. 2.9%) (P < 0.01) and multiple pregnancies reduced to twins than primary twins (38.5% vs. 27.3%) (P < 0.01). The maternal serum E₂ level at 8 weeks of gestation increased with the number of fetuses and was negatively correlated with offspring birth weight. CDKN1C and DNMT1 expression was significantly upregulated in embryo tissue, placenta, and cord blood from multiple pregnancies. Furthermore, there was a positive correlation between CDKN1C mRNA expression and KvDMR1 methylation levels. In HTR8 cells, DNMT1 mediated the estrogen-induced upregulation of CDKN1C, which might contribute to SGA. To minimize the risks of LBW and SGA, our findings suggest that abnormally high maternal serum E₂ levels should be avoided during the first trimester of multiple pregnancies from assisted reproductive technology (ART).

Gestational diabetes mellitus - A metabolic and reproductive disorder

Maternal health associated with Gestational Diabetes Mellitus (GDM) has been gaining significant research attention due to its severe risk and adverse health effects. GDM is the leading health disease in pregnant women. It is the most common metabolic disease and it can affect up to 25% of women during pregnancy. Pregnancy is a sensitive period that impacts both pregnant women and their unborn children's long-term health. It is a well-known fact that the leading causes of disease and mortality worldwide are diabetes mellitus and cancer, and specifically, women with diabetes mellitus are at a higher risk of developing breast cancer (BC). Women who have diabetes are equally vulnerable to reproductive diseases. Reproductive dysfunctions with diabetes are mainly attributed to coexisting polycystic ovarian syndrome (PCOS), obesity, and hyperinsulinemia, etc. Moreover, India has long been recognized as the world's diabetic capital, and it is widely acknowledged that particularly pregnant and lactating women are among the most affected by diabetes. In India, one-third (33%) of women with GDM had a history of maternal diabetes. Nevertheless, the latest research suggests that gestational diabetes is also a risk factor for cardiometabolic diseases of the mother and offspring. Therefore, in the 21st century, GDM imposes a major challenge for healthcare professionals. We intend to explore the role of diabetes on female reproductive function throughout various stages of life in the perspective of the changing prognosis, prevalence, and prevention of GDM.

Modelling gestational diabetes mellitus: large animals hold great promise

Gestational diabetes mellitus (GDM) characterized by hyperglycemia during pregnancy is a risk factor for various maternal and fetal complications. The key pathophysiological mechanisms underlying its development have not been elucidated, largely due to the lack of a model that accurately simulates the major clinical and pathological features of human GDM. In this review, we discuss the refined criteria for an ideal animal model of GDM, focusing on the key clinical and pathophysiological characteristics of human GDM. We provide a comprehensive overview of different models and currently used species for GDM research. In general, insulin insufficiency consequent to pancreatic β-cell death represents the current leading strategy to mimic human GDM-like hyperglycemia in animals. Nonetheless, these models have a limited capacity to mimic the natural history of GDM, the marked alteration in circulating estrogen/ progestogen, obesity and its related metabolic complications. We discuss emerging evidence of the increased susceptibility to GDM in rodents and large animals with genetic modifications in pregnancy-related hormones. An appraisal of current GDM models suggests that a combination strategy involving dietary stress, pregnancy-related hormones, insulin resistance and metabolic disorders might enable the development of better GDM models and expedite the translation of basic research findings to GDM treatment.

Early Prediction of Gestational Diabetes Mellitus in the Chinese Population via Advanced Machine Learning

CONTEXT

Accurate methods for early gestational diabetes mellitus (GDM) (during the first trimester of pregnancy) prediction in Chinese and other populations are lacking.

OBJECTIVES

This work aimed to establish effective models to predict early GDM.

METHODS

Pregnancy data for 73 variables during the first trimester were extracted from the electronic medical record system. Based on a machine learning (ML)-driven feature selection method, 17 variables were selected for early GDM prediction. To facilitate clinical application, 7 variables were selected from the 17-variable panel. Advanced ML approaches were then employed using the 7-variable data set and the 73-variable data set to build models predicting early GDM for different situations, respectively.

RESULTS

A total of 16 819 and 14 992 cases were included in the training and testing sets, respectively. Using 73 variables, the deep neural network model achieved high discriminative power, with area under the curve (AUC) values of 0.80. The 7-variable logistic regression (LR) model also achieved effective discriminate power (AUC = 0.77). Low body mass index (BMI) (≤ 17) was related to an increased risk of GDM, compared to a BMI in the range of 17 to 18 (minimum risk interval) (11.8% vs 8.7%, P = .09). Total 3,3,5'-triiodothyronine (T3) and total thyroxin (T4) were superior to free T3 and free T4 in predicting GDM. Lipoprotein(a) was demonstrated a promising predictive value (AUC = 0.66).

CONCLUSIONS

We employed ML models that achieved high accuracy in predicting GDM in early pregnancy. A clinically cost-effective 7-variable LR model was simultaneously developed. The relationship of GDM with thyroxine and BMI was investigated in the Chinese population.

Intrauterine Hyperglycemia Alters the Metabolomic Profile in Fetal Mouse Pancreas in a Gender-Specific Manner

Mounting evidence has shown that intrauterine hyperglycemia exposure during critical stages of development may be contributing to the increasing prevalence of diabetes. However, little is known about the mechanisms responsible for offspring metabolic disorder. In this present study, we explored intrauterine hyperglycemia exposure on fetal pancreatic metabolome, and its potential link to impaired glucose tolerance in adult offspring. Here, using a GDM mouse model, we found the metabolome profiling of pancreas from male and female fetus showing altered metabolites in several important pathways, including 5-methylcytosine, α-KG, branched-chain amino acids, and cystine, which are associated with epigenetic modification, insulin secretion, and intracellular redox status, respectively. This finding suggests that intrauterine exposure to hyperglycemia could cause altered metabolome in pancreas, which might be a metabolism-mediated mechanism for GDM-induced intergenerational diabetes predisposition.

Molecular mechanisms governing offspring metabolic programming in rodent models of in utero stress

The results of different human epidemiological datasets provided the impetus to introduce the now commonly accepted theory coined as 'developmental programming', whereby the presence of a stressor during gestation predisposes the growing fetus to develop diseases, such as metabolic dysfunction in later postnatal life. However, in a clinical setting, human lifespan and inaccessibility to tissue for analysis are major limitations to study the molecular mechanisms governing developmental programming. Subsequently, studies using animal models have proved indispensable to the identification of key molecular pathways and epigenetic mechanisms that are dysregulated in metabolic organs of the fetus and adult programmed due to an adverse gestational environment. Rodents such as mice and rats are the most used experimental animals in the study of developmental programming. This review summarises the molecular pathways and epigenetic mechanisms influencing alterations in metabolic tissues of rodent offspring exposed to in utero stress and subsequently programmed for metabolic dysfunction. By comparing molecular mechanisms in a variety of rodent models of in utero stress, we hope to summarise common themes and pathways governing later metabolic dysfunction in the offspring whilst identifying reasons for incongruencies between models so to inform future work. With the continued use and refinement of such models of developmental programming, the scientific community may gain the knowledge required for the targeted treatment of metabolic diseases that have intrauterine origins.

Antidiabetic effects of a lipophilic extract obtained from flowers of Wisteria sinensis by activating Akt/GLUT4 and Akt/GSK3β

Background

Type 2 diabetes mellitus is primarily caused by insulin resistance (IR) in insulin-sensitive tissues, including liver, white adipose tissues (WAT), and skeletal muscles. Discovering nutritious foods with antidiabetic effects is of great significance. Numerous published reports indicated that protein kinase B (Akt) and glucose transporter 4 (GLUT4) play crucial roles in ameliorating IR and diabetic symptoms.

Objective

In the present study, antidiabetic effects and the potential mechanism of action of WS-PE (a lipophilic extract from edible flowers of Wisteria sinensis) were explored with L6 cells in vitro and in high-fat diet (HFD) + Streptozocin (STZ)-induced diabetic mice in vivo.

Design

In vivo, HFD + STZ-induced diabetic mice were used as diabetic models to investigate the potential antidiabetic and antidyslipidemic activities. In vitro, a novel GLUT4 translocation assay system was established to evaluate the potential effects of WS-PE on GLUT4 translocation. Western blot analysis was adopted to investigate the molecular mechanisms of WS-PE both in vivo and in vitro.

Results

vitro, WS-PE increased glucose uptake by stimulating GLUT4 expression and translocation, which were regulated by Akt phosphorylation. In vivo, the WS-PE treatment ameliorated the hyperglycemia, IR, and dyslipidemia and reversed hepatic steatosis and pancreatic damage in diabetic mice. The WS-PE treatment increased GLUT4 expression by Akt activation in WAT and skeletal muscle. Akt activation stimulated GSK3β phosphorylation in liver and skeletal muscles, indicating that WS-PE showed regulatory effects on glycogen synthesis in liver and skeletal muscles.

Conclusion

These in vitro and in vivo results indicated that the WS-PE treatment exerted antidiabetic effects by activating Akt/GLUT4 and Akt/GSK3β.

Relationship of prenatal maternal obesity and diabetes to offspring neurodevelopmental and psychiatric disorders: a narrative review

Obesity and diabetes is a worldwide public health problem among women of reproductive age. This narrative review highlights recent epidemiological studies regarding associations of maternal obesity and diabetes with neurodevelopmental and psychiatric disorders in offspring, and provides an overview of plausible underlying mechanisms and challenges for future human studies. A comprehensive search strategy selected terms that corresponded to the domains of interest (maternal obesity, different types of diabetes, offspring cognitive functions and neuropsychiatric disorders). The databases searched for articles published between January 2010 and April 2019 were PubMed, Web of Science and CINAHL. Evidence from epidemiological studies strongly suggests that maternal pre-pregnancy obesity is associated with increased risks for autism spectrum disorder, attention-deficit hyperactivity disorder and cognitive dysfunction with modest effect sizes, and that maternal diabetes is associated with the risk of the former two disorders. The influence of maternal obesity on other psychiatric disorders is less well studied, but there are reports of associations with increased risks for offspring depression, anxiety, schizophrenia and eating disorders, at modest effect sizes. It remains unclear whether these associations are due to intrauterine mechanisms or explained by confounding family-based sociodemographic, lifestyle and genetic factors. The plausible underlying mechanisms have been explored primarily in animal models, and are yet to be further investigated in human studies.

Exploring the causes and consequences of maternal metabolic maladaptations during pregnancy: Lessons from animal models

Pregnancy is a remarkable physiological state, during which the metabolic system of the mother adapts to ensure that nutrients are made available for transfer to the fetus for growth and development. Adaptations of maternal metabolism during pregnancy are influenced by the metabolic and nutritional status of the mother and the production of endocrine factors by the placenta that exert metabolic effects. Insufficient or inappropriate adaptations in maternal metabolism during pregnancy may lead to pregnancy complications with important short- and long-term effects for both the health of the child and mother. This is very evident in gestational diabetes, which is marked by greater glucose intolerance and insulin resistance above that expected of a normal pregnancy. Gestational diabetes is associated with increased fetal weight and/or increased adiposity, higher instrumented delivery rates and greater risks for both mother and child of developing type 2 diabetes in the long-term. However, despite the negative health impacts of such metabolic imbalances during pregnancy, the precise mechanisms responsible for orchestrating these changes remain largely unknown. The present review describes the dynamic pregnancy-specific changes that occur in the metabolic system of the mother during pregnancy. It also discusses findings using surgical, pharmacological, genetic and dietary methods in experimental animals that highlight the role of pathways in maternal tissues that lead to metabolic dysfunction, with a particular focus on gestational diabetes. Finally, it summarises the work largely employing gene targeting and hormone administration in rodents that have illuminated the involvement of placental endocrine function in driving maternal metabolic adaptations. While current animal models may not fully replicate what is observed in humans, these have been instrumental in showing that there is a dynamic interplay between changes in maternal metabolic physiology and the placental production of endocrine factors that govern the availability of nutrients to the growing fetus. However, more work is required to specifically identify the placenta-driven changes in maternal metabolic physiology that ensure the appropriate level of insulin production and action during pregnancy. In doing so, these studies may pave the way to understanding the development of pregnancy complications like gestational diabetes, as well as further our understanding of type-2 diabetes and the control of metabolic physiology more broadly.

MiRNA-221 protects islet β cell function in gestational diabetes mellitus by targeting PAK1

To elucidate the potential function of miRNA-221 in gestational diabetes mellitus (GDM) and the underlying mechanism. MiRNA-221 level was analyzed in the microarray containing placental tissues of GDM rats. After constructing GDM model in rats, miRNA-221 level in placental tissues of GDM rats or controls was determined as well. The relationship between miRNA-221 level and blood glucose in GDM rats was analyzed by Spearman correlation test. Regulatory effects of miRNA-221 on proliferation, apoptosis and insulin secretion in INS-1 cells were assessed. Through dual-luciferase reporter gene assay, the direct target of miRNA-221, PAK1 was identified. At last, potential influences of miRNA-221/PAK1 axis on INS-1 cell phenotypes were determined. MiRNA-221 was downregulated in placental tissues of GDM rats, and its level was negatively correlated to that of blood glucose level in GDM rats. Overexpression of miRNA-221 stimulated insulin secretion, cell proliferation and suppressed apoptosis in INS-1 cells. Knockdown of miRNA-221 achieved the opposite results. PAK1 was proved as the direct target of miRNA-221. Notably, PAK1 was able to reverse regulatory effects of miRNA-221 on INS-1 cell phenotypes. MiRNA-221 regulates proliferation, apoptosis and insulin secretion in islet β cells through targeting PAK1, thus protecting GDM-induced islet dysfunction.