What is gestational diabetes?

Pre-pregnancy menstrual cycle regularity and length and the risk of gestational diabetes mellitus: prospective cohort study

AIMS/HYPOTHESIS

Menstrual cycle dysfunction has been associated with many endocrine-related diseases, but evidence linking menstrual cycle dysfunction with gestational diabetes mellitus (GDM) is scant. The current study investigated the association of pre-pregnancy menstrual cycle regularity and length during adolescence, early adulthood and mid-adulthood with the subsequent risk of GDM.

METHODS

Between 1993 and 2009, we followed 10,906 premenopausal women participating in the Nurses' Health Study II who reported menstrual cycle characteristics during adolescence (age 14-17 years), early adulthood (age 18-22 years) and mid-adulthood (age 29-46 years). Incident GDM was ascertained from a self-reported questionnaire regarding physician diagnosis. Log-binomial models with generalised estimating equations were used to estimate the RRs and 95% CI for the associations between menstrual cycle characteristics and GDM.

RESULTS

We documented 578 incident cases of GDM among 14,418 pregnancies over a 16 year follow-up. After adjusting for potential confounders, women reporting always having irregular menstrual cycles during mid-adulthood had a 65% (95% CI 21, 125%) higher risk of GDM than women reporting very regular cycles. GDM risk was also greater among women reporting that their cycles were usually ≥32 days during mid-adulthood, compared with women reporting cycles between 26 and 31 days (RR 1.42 [95% CI 1.15, 1.75]). The risk of GDM was greater for women whose cycles changed from regular early in their reproductive years to irregular or from <32 days to ≥32 days during mid-adulthood, compared with women whose cycles remained <32 days or regular, respectively.

CONCLUSIONS/INTERPRETATION

Women whose cycles were long or irregular during mid-adulthood, but not in adolescence or young adulthood, were at higher risk of GDM.

Novel association between a transient receptor potential cation channel subfamily M member 5 expression quantitative trait locus rs35197079 and decreased susceptibility of gestational diabetes mellitus in a Chinese population

AIMS/INTRODUCTION

Emerging evidence suggests that expression quantitative trait loci (eQTLs) are more likely to associate with complex diseases. Transient receptor potential cation channel subfamily M member 5 (TRPM5) is a ubiquitously expressed voltage-gated cation channel that acts indispensably to trigger insulin secretion in pancreatic β-cells. The present study evaluated the association between TRPM5 eQTL single-nucleotide polymorphisms and the risk of gestational diabetes mellitus (GDM) in a Chinese population.

MATERIALS AND METHODS

A total of 380 unrelated Chinese pregnant women including 241 GDM patients and 139 controls were included in this study. The eQTL single-nucleotide polymorphisms of TRPM5 were obtained from the GTEx eQTL Browser, and were subsequently genotyped using the Agena MassARRAY iPLEX platform.

RESULTS

Logistic regression analysis and linear regression analysis showed that rs35197079 and rs74848824 were significantly associated with reduced GDM risk and lower fasting plasma glucose levels after adjusting confounder factors in dominant genetic models. Stratification analysis based on pre-pregnancy body mass index validated a strong association between rs35197079 and GDM susceptibility in underweight and normal weight individuals. Luciferase and electrophoretic mobility shift assays carried out in rat pancreatic β-cells showed that rs35197079 was functional.

CONCLUSIONS

The TRPM5 eQTL single-nucleotide polymorphism rs35197079 was associated with decreased GDM susceptibility in a Chinese population, especially in underweight and normal weight pregnant women, and it was functional in modulating gene transcription.

Are single nucleotide polymorphisms rs7903146 and rs12255372 in transcription factor 7-like 2 gene associated with an increased risk for gestational diabetes mellitus in Egyptian women?

BACKGROUND

Genetic variants in the transcription factor 7-like 2 (TCF7L2) gene are related with type 2 diabetes (T2D) and gestational diabetes mellitus (GDM) in various populations, but there are not enough statistics regarding GDM among Egyptian women. We aimed by this study to evaluate the effect of two polymorphisms of rs7903146 and rs12255372 in the TCF7L2 gene with the development of GDM among Egyptian women.

RESULTS

We enrolled 114 pregnant women with normal glucose tolerance and 114 with GDM according to the International Association of Diabetes and Pregnancy Study Groups (IADPSG) guidelines. We gathered records on blood pressure, body mass index (BMI), blood glucose level, hemoglobin A1C (HbA1c), and lipid profile. The genotyping of rs7903146 and rs12255372 polymorphisms was carried out using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The statistical significance of prepregnancy BMI, fasting blood sugar (FBS), HbA1c, low-density lipoprotein (LDL), and total cholesterol (Tch) was higher, P < 0.001, in GDM women in comparison to pregnant women without GDM. CT and TT genotypes in rs7903146 SNP were 46.5% vs. 54%, P <0.04, OR; CI = 1.9 (1.0 to 3.78); TT carriers were 37.7% vs. 9.6%, P <0.001, OR (CI) = 8.9 (3.7-21.1), respectively. For the TCFL2 gene rs12255372 SNP, GT carriers were 48.2% vs. 39.5%, P= 0.004, OR (CI) = 2.3 (1.3-4.2), while TT carriers were 24.6% vs. 7.9%, P < 0.001, OR (CI) = 6 (2.5-14.3).

CONCLUSION

The study showed there is a significantly higher incidence of CT/TT genotypes in rs7903146 SNP and GT/TT genotypes in rs12255372 SNP in TCF7L2 gene among GDM women in comparison to healthy pregnant women (controls).

The Modulation of Gut Microbiota Composition in the Pathophysiology of Gestational Diabetes Mellitus: A Systematic Review

Simple Summary

Recent studies have placed a great deal of emphasis on the importance of the microbiome, especially the link between the alteration of gut microbiota and multiple associated diseases. Gut microbiota changes in pregnancy have a significant impact on metabolic function and may contribute to gestational diabetes mellitus (GDM). Although GDM carries long-term health risks that affect women, there are also significant short- and severe long-term consequences for the offspring. Regardless, there is a notable lack of research focusing on the impact of prominent microorganisms involved in the development of GDM. A comprehensive review was conducted to gather relevant data on the types of microorganisms that have been associated with GDM. The review found that certain microorganisms impact the onset and progression of GDM during pregnancy. Several bacterial strains associated with GDM are influenced by a diet high in fat and low in fiber. Therefore, integrating the idea of a microbiome-based individualized dietary intervention into gestational diabetes management may be incredibly beneficial.

Abstract

General gut microbial dysbiosis in diabetes mellitus, including gestational diabetes mellitus (GDM), has been reported in a large body of literature. However, evidence investigating the association between specific taxonomic classes and GDM is lacking. Thus, we performed a systematic review of peer-reviewed observational studies and trials conducted among women with GDM within the last ten years using standard methodology. The National Institutes of Health (NIH) quality assessment tools were used to assess the quality of the included studies. Fourteen studies investigating microbial interactions with GDM were found to be relevant and included in this review. The synthesis of literature findings demonstrates that Bacteroidetes, Proteobacteria, Firmicutes, and Actinobacteria phyla, such as Desulfovibrio, Ruminococcaceae, P. distasonis, Enterobacteriaceae, Collinsella, and Prevotella, were positively associated with GDM. In contrast, Bifidobacterium and Faecalibacterium, which produce butyrate, are negatively associated with GDM. These bacteria were associated with inflammation, adiposity, and glucose intolerance in women with GDM. Lack of good diet management demonstrated the alteration of gut microbiota and its impact on GDM glucose homeostasis. The majority of the studies were of good quality. Therefore, there is great potential to incorporate personalized medicine targeting microbiome modulation through dietary intervention in the management of GDM.

The implications of the purinergic signaling throughout pregnancy

Purinergic signaling is a necessary mechanism to trigger or even amplify cell communication. Its ligands, notably adenosine triphosphate (ATP) and adenosine, modulate specific membrane-bound receptors in virtually all human cells. Regardless of the stage of the pregnancy, cellular communication between maternal, placental, and fetal cells is the paramount mechanism to sustain its optimal status. In this review, we describe the crucial role of purinergic signaling on the regulation of the maternal-fetal trophic exchanges, immune control, and endocrine exchanges throughout pregnancy. The nature of the modulation of both ATP and adenosine on the embryo-maternal interface, going through placental invasion until birth delivery depends on the general maternal-fetal health state and consequently on the selective activation of their specific receptors. In addition, an increasing number of studies have been demonstrating the pivotal role of ATP and adenosine in modulating deleterious effects of suboptimal conditions of pregnancy. Here, we discuss the role of purinergic signaling on the balance that coordinates the embryo-maternal exchanges and a promising therapeutic venue in the context of pregnancy disorders.

Theranostic Advances of Bionanomaterials against Gestational Diabetes Mellitus: A Preliminary Review

Gestational diabetes mellitus (GDM) is the most frequent complication during pregnancy. This complex disease is characterized by glucose intolerance and consequent hyperglycemia that begins or is first diagnosed in pregnancy, and affects almost 7% of pregnant women. Previous reports have shown that GDM is associated with increased pregnancy complications and might cause abnormal fetal development. At present, treatments are not suitable for the prevention and management of these patients. As an alternative therapeutic opportunity and a leading scientific technique, nanotechnology has helped enlighten the health of these affected women. Theranostic nanomaterials with unique properties and small sizes (at least <100 nm in one of their dimensions) have been recently engineered for clinics and pharmaceutics. Reducing materials to the nanoscale has successfully changed their properties and enabled them to uniquely interact with cell biomolecules. Several biosensing methods have been developed to monitor glucose levels in GDM patients. Moreover, cerium oxide nanoparticles (NPs), selenium NPs, polymeric NPs, and drug-loaded NPs loaded with therapeutic agents have been used for GDM treatment. Still, there are some challenges associated with the detection limits and toxicity of such nanomaterials. This preliminary review covers the aspects from a fast-developing field to generating nanomaterials and their applications in GDM diagnosis and treatment.

Improving nutrition for the prevention of gestational diabetes: Current status and perspectives

Gestational diabetes mellitus (GDM) is a common complication of pregnancy and a serious public health problem. It carries significant risks of short-term and long-term adverse health effects for both mothers and their children. Risk factors, especially modifiable risk factors, must be considered to prevent GDM and its consequences. Observational studies have identified several nutritional and lifestyle factors associated with the risk of GDM. The results of intervention studies examining the effects of diet and lifestyle on the prevention of GDM are contradictory. Differences in the study populations, types and intensity of intervention, time frame of the intervention, and diagnostic criteria for GDM may explain the heterogeneity in the results of intervention studies. This review provides an overview of new diets and other factors that may help prevent GDM. The main results of epidemiological studies assessing the risk factors for GDM, as well as the results and methodological problems of intervention studies on the prevention of GDM and their meta-analyses, are discussed. In addition, the evidence that gene and lifestyle interactions influence the development of GDM, as well as prospects for increasing the effectiveness of interventions designed to prevent GDM, including new data on the possible uses of personalized diet therapy, are highlighted.

Association between maternal plasma ferritin concentration, iron supplement use, and the risk of gestational diabetes: a prospective cohort study

BACKGROUND

The association between iron supplementation and gestational diabetes mellitus (GDM) is still inconclusive, and this association has not been extensively studied in relation to plasma ferritin in the early second trimester.

OBJECTIVES

We aimed to prospectively examine the independent and combined associations of plasma ferritin concentrations and iron supplement use with GDM.

METHODS

We studied 2117 women from the Tongji Maternal and Child Health Cohort in Wuhan, China. Plasma ferritin around 16 weeks' gestation was measured by ELISA kits and information on iron supplement use was collected by questionnaires. GDM was diagnosed by a 75-g oral-glucose-tolerance test (OGTT) at 24-28 weeks' gestation. A log-Poisson regression model was used to estimate the RR of GDM associated with plasma ferritin and iron supplementation.

RESULTS

The median and IQR of plasma ferritin was 52.1 (29.6-89.9) ng/mL, and 863 (40.8%) participants reported use of iron supplements during the second trimester. A total of 219 (10.3%) participants developed GDM. Adjusted RRs (95% CIs) for GDM across increasing quartiles of plasma ferritin were 1.00 (reference), 2.14 (1.37, 3.34), 2.03 (1.30, 3.19), and 2.72 (1.76, 4.21), respectively. After adjustment, supplemental iron ≥60 mg/d during the second trimester was associated with an increased risk of GDM compared with nonusers (RR: 1.37; 95% CI: 1.02, 1.84).

CONCLUSIONS

Both elevated plasma ferritin concentrations in the early second trimester and use of ≥60 mg/d of supplemental iron during pregnancy are independently associated with increased risk of GDM. Further clinical trials with precision nutrition approaches considering both baseline iron status and supplement use are needed to evaluate the benefits and risks of iron supplementation during pregnancy.

Formyl peptide receptor-2 is upregulated in the blood and placenta of patients with gestational diabetes mellitus

Aim

To investigate the expression of formyl peptide receptor 2 (FPR2) in maternal blood, umbilical blood, and placenta of patients with gestational diabetes mellitus (GDM), and to analyze the changes of other pro‐inflammatory cytokines in blood, including interleukin 33 (IL‐33), IL‐1β, tumor necrosis factor alpha (TNF‐α), and C‐reactive protein (CRP), so as to reveal the pathogenesis of GDM.

Methods

FPR2, IL‐33, IL‐1β, T TNF‐α, and CRP in maternal blood and umbilical cord blood of 50 pregnant women with GDM and 30 normal pregnant women were analyzed by ELISA method to explore the correlation between inflammatory factors and blood glucose. The expression of FPR2 in placental tissues was analyzed by PCR and immunohistochemistry.

Results

The expression of FPR2 in maternal blood of gestational diabetes patients was significantly higher than that of normal pregnant women, and other inflammatory factors IL‐33 and IL‐1β in maternal blood were also significantly increased. The expression of FPR2 in umbilical cord blood of gestational diabetes was higher than that of normal pregnant women, but the difference was not significant. Other inflammatory factors IL‐33, IL‐1β, and CRP in umbilical cord blood were also significantly increased. The expression of FPR2mRNA and protein in placental tissues of gestational diabetes was significantly higher than that of normal pregnant women.

Conclusions

The level of FPR2, IL‐33, and IL‐1β in maternal blood was related to the pathogenesis of GDM and these inflammatory factors could be used as special candidate direction of marks for the prevention, clinical treatment and drug design of GDM, laying a new theoretical foundation for the treatment of GDM.

Overweight and obesity in pregnancy: their impact on epigenetics

Over the last few decades, the prevalence of obesity has risen to epidemic proportions worldwide. Consequently, the number of obesity in pregnancy has risen drastically. Gestational overweight and obesity are associated with impaired outcomes for mother and child. Furthermore, studies show that maternal obesity can lead to long-term consequences in the offspring, increasing the risk for obesity and cardiometabolic disease in later life. In addition to genetic mechanisms, mounting evidence demonstrates the induction of epigenetic alterations by maternal obesity, which can affect the offspring’s phenotype, thereby influencing the later risk of obesity and cardiometabolic disease. Clear evidence in this regard comes from various animal models of maternal obesity. Evidence derived from clinical studies remains limited. The current article gives an overview of pathophysiological changes associated with maternal obesity and their consequences on placental structure and function. Furthermore, a short excurse is given on epigenetic mechanisms and emerging data regarding a putative interaction between metabolism and epigenetics. Finally, a summary of important findings of animal and clinical studies investigating maternal obesity-related epigenetic effects is presented also addressing current limitations of clinical studies.

Growth-differentiation-factor 15 levels in obese and healthy pregnancies: Relation to insulin resistance and insulin secretory function

OBJECTIVE/AIM

Growth-differentiation-factor 15 (GDF15) has been suggested to improve or protect beta cell function. During pregnancy, beta cell numbers and function increase to overcome the natural rise in insulin resistance during gestation. In this study, we longitudinally measured serum GDF15 levels during and after pregnancy in women of normal weight (NW) and in women with obesity (OB) and explored associations between GDF15 and changes in beta cell function by homeostatic model assessment (HOMA).

METHODS

The cohort participants were 38 NW (BMI 22.3 ± 1.7) and 35 OB (BMI 35.8 ± 4.2). Blood was sampled and body composition measured at each trimester (T1, T2, and T3) and at 6, 12 and 18 months postpartum. Fasting glucose, insulin and GDF15 were measured, and HOMA for insulin resistance (HOMA-IR) and beta cell function (HOMA-B) determined.

RESULTS

GDF15 levels increased significantly each trimester and were ~200-fold higher at T3 than in the nonpregnant postpartum state. GDF15 was higher in NW than OB during pregnancy, but was reversed after pregnancy with a significant interaction effect. GDF15 correlated inversely with BMI and fat-free mass at T3. Low GDF15 was associated with lower incidence of nausea and with carrying a male foetus. The pregnancy induced increase in GDF15 associated with increased HOMA-B in OB and with reduced fasting glucose in all women.

CONCLUSION

Large gestational upregulation of GDF15 levels may help increase insulin secretory function to overcome pregnancy-induced insulin resistance.

Association Between Neutrophil-Lymphocyte Ratio and Gestational Diabetes-A Systematic Review and Meta-Analysis

A growing body of evidence shows that the neutrophil-lymphocyte ratio (NLR) is a surrogate index of systemic inflammation in several chronic diseases. Conflicting associations between NLR and gestational diabetes mellitus (GDM) have been reported in individual studies. This meta-analysis sought to investigate the association between NLR and GDM. The PubMed, EMBASE, and Google Scholar databases were searched to identify relevant articles. The pooled standardized mean difference with 95% CI was calculated using a random-effects model. Subgroup and meta-regression analysis were carried out to control for the effects of GDM diagnostic criteria, ethnicity, body mass index (BMI), and age. Eleven eligible articles were included, containing 1271 participants with GDM and 1504 controls. Pooled outcomes indicated a higher NLR in GDM pregnancies than in normoglycemic controls (SMD = 0.584; 95% CI, 0.339-0.830; P < .001), although extensive heterogeneity between studies was noted. Subgroup analysis revealed that the higher pooled estimate in GDM was not affected by diagnostic criteria, ethnicity, or BMI, although matching for BMI reduced heterogeneity between studies. This meta-analysis supports the higher NLR in GDM described by some individual studies.

Gestational diabetes mellitus by maternal country of birth and length of residence in immigrant women in Norway

AIMS

Immigrant women are at higher risk for gestational diabetes mellitus (GDM) than non-immigrant women. This study described the prevalence of GDM in immigrant women by maternal country of birth and examined the associations between immigrants' length of residence in Norway and GDM.

METHODS

This Norwegian national population-based study included 192,892 pregnancies to immigrant and 1,116,954 pregnancies to non-immigrant women giving birth during the period 1990-2013. Associations were reported as odds ratios (ORs) with 95% confidence intervals (CIs) using logistic regression models, adjusted for year of delivery, maternal age, marital status, health region, parity, education and income.

RESULTS

The prevalence and adjusted OR [CI] for GDM were substantially higher in immigrant women from Bangladesh (7.4%, OR 8.38 [5.41, 12.97]), Sri Lanka (6.3%, OR 7.60 [6.71, 8.60]), Pakistan (4.3%, OR 5.47 [4.90, 6.11]), India (4.4%, OR 5.18 [4.30, 6.24]) and Morocco (4.3%, OR 4.35 [3.63, 5.20]) compared to non-immigrants (prevalence 0.8%). Overall, GDM prevalence increased from 1.3% (OR 1.25 [1.14, 1.36]) to 3.3% (OR 2.55 [2.39, 2.71]) after 9 years of residence in immigrants compared to non-immigrant women. This association was particularly strong for women from South Asia.

CONCLUSIONS

Gestational diabetes mellitus prevalence varied substantially between countries of maternal birth and was particularly high in immigrants from Asian countries. GDM appeared to increase with longer length of residence in certain immigrant groups.

The Role of Oxidative Stress in Hypertensive Disorders of Pregnancy (Preeclampsia, Gestational Hypertension) and Metabolic Disorder of Pregnancy (Gestational Diabetes Mellitus)

Purpose of the Review.To highlight the role of oxidative stress in hypertensive disorders of pregnancy (HDP) and metabolic disorders of pregnancy (gestational diabetes mellitus). Recent Findings. In both preeclampsia (PE) and gestational hypertension (GH), oxidative stress leads to inadequate placental perfusion thus resulting in a hypoxic placenta, which generally leads to the activation of maternal systemic inflammatory response. In PE, this causes inflammation in the kidneys and leads to proteinuria. A proteinuria marker known as urinary 8-oxoGuo excretion is expressed in preeclampsia. In GDM, oxidative stress plays a role in the pathogenesis of the disease, as a result of over secretion of insulin during pregnancy. This uncontrolled secretion of insulin results in the production of lipid peroxidation factors that also mask the secretion of antioxidants. Therefore, ROS becomes abundant at cellular level and prevents the cells from transporting glucose to body tissues. Summary. There is a need for more research investigating the role of oxidative stress, especially in obstetrics-related conditions. More studies are required in order to understand the difference between the pathogenesis and pathophysiology of PE versus GH since investigations on the differences in genetic aspects of each condition are lacking. Furthermore, research to improve diagnostic procedures for GDM in pregnancy is needed.

An evaluation of dietary intakes of a selected group of South Asian migrant women with gestational diabetes mellitus

Background: Women of South Asian descent have an increased risk of developing gestational diabetes mellitus (GDM), and type 2 diabetes mellitus compared to Caucasian women. Dietary advice provided by health practitioners to this group has been found to be culturally inappropriate. The aim of this study was to describe the dietary intakes of South Asian women with gestational diabetes and use this information to develop culturally appropriate dietary models for education and support of dietary management.Method: An in-depth diet and lifestyle survey was administered with 13 eligible women. Dietary histories were collected for pre-pregnancy, during pregnancy and post-GDM diagnosis to evaluate changes in dietary intake, diet and health beliefs and traditional foods consumed during pregnancy.Results: The diets of participants did not meet nutrient requirements for pregnancy; specific areas on concern were dietary fibre, calcium, iron, folate and iodine. Vegetarians were particularly at risk with regards to energy and protein intake. Generally dietary intakes of these women with GDM were not consistent with guidelines for management of GDM. Confusion about what they should eat for GDM, health practitioner advice and conflict with cultural expectations about foods to consume during pregnancy was evident.Conclusion: The dietary information collected from these women was used to model sample menus for GDM that were culturally appropriate and consistent with vegetarian and non-vegetarian eating patterns.

Pregnant Women Have Poor Carbohydrate Knowledge and Do Not Receive Adequate Nutrition Education

OBJECTIVES

In order to manage blood glucose levels in pregnancy, women need to know what and how much to eat, particularly for foods containing carbohydrate. The aim was to assess pregnant women's carbohydrate and standard serve size knowledge and examine whether health professionals provided nutrition education.

METHODS

Between July 2017 and April 2018 Australian pregnant women were recruited to complete an online survey, including a modified PedCarbQuiz carbohydrate knowledge questionnaire and an online buffet, where they selected images equivalent to one Australian Guide to Healthy Eating (AGHE) standard serve size.

RESULTS

186 pregnant women (mean age 30.9 years, SD = 4.7 years) 12-22 weeks gestation completed the survey. Participants achieved a median score of 27/36 for identification of carbohydrate-containing foods and a median score of 1/12 (range 0-11) for identification of grams of carbohydrate in specific portions. Participants achieved a median score of 14/22 (range 4-19) for identification of one AGHE standard serve of 11 carbohydrate-containing foods. Less than half (n = 92, 49.5%) received nutrition education from health professionals.

CONCLUSIONS FOR PRACTICE

Pregnant women had sub-optimal carbohydrate knowledge. This could contribute to impaired blood glucose concentrations and risk of adverse health outcomes in pregnancy. Opportunities for pregnant women to access nutrition advice from health professionals should be explored.

The effect of Gestational Diabetes Mellitus on the fetal compartment

In indicated preterm births such a Gestational Diabetes Mellitus (GDM), little is known about the role of the amnion membranes. Investigating the role of amnion membrane inflammation in response GDM may suggest novel pathophysiologic mechanisms. We hypothesize that increased GDM inflammatory mediators may weaken the amnion membrane predisposing them to infection. Maternal and fetal serum and amnion membrane biopsies were collected from 20 GDM and 38 normoglycemic subjects (control) who underwent elective cesarean sections. Cytokines and adipokines were evaluated in serum and amnion culture supernatant samples. Amnion membrane biopsies from GDM and control subjects were studied: fresh frozen for RNA analysis for Toll-like receptor expression; cultured with LPS to test membrane permeability, and inflammation LPS + anti-TLR4 for testing mechanism. GDM was associated with higher fetal serum leptin (p = 0.004) and IL-10 (p = 0.04) compared to controls. Amnion membrane explants from GDM had higher levels of IL-6 (p = 0.019), and lower expression of Claudin-4 (p = 0.007) and increased permeability (p = 0.046) compared to controls. GDM membranes treated with LPS showed an increased expression of IL-10 (p = 0.013); IL-6 (p = 0.004) and TNF-α (p = 0.0005) but did not affect membrane permeability. LPS and anti-TLR4 antibody treatment reduced the production of TNF-α in controls (p = 0.03) and GDM (p = 0.007) compared to LPS alone. Fetal inflammatory response seems more balanced in GDM and does not impact membrane permeability function even with an infectious stimulus. Light fetal membrane inflammatory response may explain lack of preterm labor in GDM. Concluding, benign inflammation in the membranes may not be harmful for pregnancy maintenance.

Plasma metabolites, especially lipid metabolites, are altered in pregnant women with gestational diabetes mellitus

BACKGROUND AND AIMS

Gestational diabetes mellitus (GDM) is a pathological condition of glucose intolerance associated with adverse pregnancy outcomes and increased risk of developing maternal type 2 diabetes later in life. Metabolomics is finding increasing use in the study of GDM. To date, GDM-specific metabolomic changes have not been completely elucidated.

MATERIALS AND METHODS

In this pilot study, metabolomics fingerprinting data, obtained by ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UHPLC/Q-TOF-MS), of 54 healthy pregnant women and 49 patients with GDM at the second and third gestational trimesters were analyzed. Multilevel statistical methods were used to process complex metabolomic data from the retrospective cohorts.

RESULTS

Using univariate analysis (p < 0.05), 41 metabolites were identified as having the most significant differences between these two groups. Lipid metabolites, particularly glycerophospholipids, were the most prevalent class of altered compounds. In addition, metabolites with previously unknown connection to GDM - such as monoacylglycerol, dihydrobiopterin, and 13S-hydroxyoctadecadienoic acid - were identified with strong discriminative power. The main metabolic pathways affected by GDM included glycerophospholipid metabolism, linoleic acid metabolism, and D-arginine and D-ornithine metabolism.

CONCLUSION

Our data provide a comprehensive overview of metabolite changes at different stages of pregnancy, which offers further insights into the pathogenesis of GDM.

Beyond protein intake: does dietary fat intake in the year preceding pregnancy and during pregnancy have an impact on gestational diabetes mellitus?

Purpose

Studies regarding the association between dietary fat intake and gestational diabetes mellitus (GDM) are limited and provide conflicting findings. Thus, the study aims to examine the association of dietary fat intake in the year preceding pregnancy and during pregnancy with the risk of GDM, taking the relevance of dietary protein intake on GDM into consideration.

Methods

A prospective study was conducted in 6299 singleton pregnancies, using the data from the Nutrition in Pregnancy and Growth in Southwest China (NPGSC). A validated food frequency questionnaire was used to assess dietary fat intake in the year preceding pregnancy and during the first and second trimesters of pregnancy. Logistic regression analysis was used to assess the prospective associations of dietary fat intake and the type and source of dietary fats in different time windows with GDM risk.

Results

Higher intake of total fat [OR (95% CI): 2.21 (1.19–4.20), P = 0.02] during 12–22 weeks of gestation was associated with higher GDM risk. However, adjustment for animal protein intake greatly attenuated this association [OR (95% CI): 1.81 (0.93, 3.64), P = 0.11]. Total fat intake neither in the year preceding pregnancy nor during the early pregnancy was associated with GDM risk. Moreover, insignificant associations were observed between intakes of vegetable fat, animal fat, cholesterol, saturated fatty acid, monounsaturated fatty acid and polyunsaturated fatty acid one year before pregnancy and during the first and second trimesters and GDM risk.

Conclusion

Our study indicated that dietary fat intake one year before pregnancy and across the two pregnancy trimesters preceding the diagnosis of GDM has no relevance on GDM risk among Chinese women, particularly those with normal BMI, low, or normal calorie intake.

Long non-coding RNA-regulated pathways in pancreatic β cells: Their role in diabetes

Long non-coding RNAs (lncRNAs) are transcripts of more than 200 nucleotides that have not coding potential, but act as gene expression regulators through several molecular mechanisms. Several studies have identified tons of lncRNAs that are expressed in pancreatic β cells and many of them have been shown to have β cell-specific expression, suggesting a potential role in the regulation of basal β cell functions. Indeed, accumulating evidence based on numerous studies, has highlighted the implication of lncRNAs in the regulation of pancreatic β cell differentiation and proliferation, insulin synthesis and secretion, and apoptosis. In addition, several lncRNAs have shown to be implicated in pancreatic β cell dysfunction linked to different types of diabetes, including type 1 and type 2 diabetes, and monogenic forms of the disease. Pathogenic conditions linked to diabetes (inflammation or lipoglucotoxicity, for example) dysregulate the expression of several lncRNAs, suggesting that changes in lncRNA may alter potentially important pathways for β cell function, and eventually leading to β cell dysfunction and diabetes development. In this sense, functional characterization of some lncRNAs has demonstrated that these non-coding molecules participate in the regulation of several crucial pathways at the pancreatic β cell level, and dysregulation of these pathways leads to pathogenic phenotypes. In this review, we provide an overview of the action mechanisms of functionally characterized lncRNAs in healthy β cells and describe the contribution of some diabetes-associated lncRNAs to pancreatic β cell failure.

Breastfeeding Duration and Development of Dysglycemia in Women Who Had Gestational Diabetes Mellitus: Evidence from the GUSTO Cohort Study

(1) Background: Breastfeeding has been shown to support glucose homeostasis in women after a pregnancy complicated by gestational diabetes mellitus (GDM) and is potentially effective at reducing long-term diabetes risk. (2) Methods: Data from the Growing Up in Singapore Towards healthy Outcomes (GUSTO) study were analyzed to understand the influence of breastfeeding duration on long-term dysglycemia (prediabetes and diabetes) risk in women who had GDM in the index pregnancy. GDM and dysglycemia four to seven years postpartum were determined by the oral glucose tolerance test (OGTT). A Poisson regression model with a robust error variance was used to estimate incidence rate ratios (IRRs) for dysglycemia four to seven years post-delivery according to groupings of the duration of any breastfeeding (<1, ≥1 to <6, and ≥6 months). (3) Results: Women who had GDM during the index pregnancy and complete breastfeeding information and OGTT four to seven years postpartum were included in this study (n = 116). Fifty-one women (44%) had postpartum dysglycemia. Unadjusted IRRs showed an inverse association between dysglycemia risk and ≥1 month to <6 months (IRR 0.91; 95% confidence interval [CI] 0.57, 1.43; p = 0.68) and ≥6 months (IRR 0.50; 95% CI 0.27, 0.91; p = 0.02) breastfeeding compared to <1 month of any breastfeeding. After adjusting for key confounders, the IRR for the ≥6 months group remained significant (IRR 0.42; 95% CI 0.22, 0.80; p = 0.008). (4) Conclusions: Our results suggest that any breastfeeding of six months or longer may reduce long-term dysglycemia risk in women with a history of GDM in an Asian setting. Breastfeeding has benefits for mothers beyond weight loss, particularly for those with GDM.

Prevalence of Gestational Diabetes Mellitus Using the Latest World Health Organization Diagnostic Criteria among Omani Women in Muscat, Oman

Objectives

In 2013, the World Health Organization (WHO) recommended new criteria for diagnosing gestational diabetes mellitus (GDM). Our study aimed to compare the incidence of GDM and its complications among Omani pregnant women using the new diagnostic criteria compared to previous criteria published in 1999.

Methods

This retrospective cohort study was conducted between January and December 2016 at the Bawshar Specialized Polyclinic in Muscat, Oman. A total of 613 Omani women were included in the study. Baseline maternal characteristics such as age, body mass index, parity, and socioeconomic status were recorded in addition to maternal and neonatal outcomes.

Results

Based on the current diagnostic criteria, the incidence of GDM was 48.5% (n = 297); however, this dropped to 26.4% (n = 162) when applying the old criteria. Moreover, rates of maternal complications including polyhydramnios (5.6% vs. 4.6%), pregnancy-induced hypertension (3.2% vs. 1.5%), and preterm delivery (3.2% vs. 1.5%) were slightly higher among women with GDM diagnosed using the latest criteria. However, these differences were not statistically significant. Neonatal complications were also slightly more frequent among the first group, without any significant differences.

Conclusions

The incidence of GDM among Omani women rose dramatically when utilizing the latest WHO diagnostic criteria, owing to a lower fasting blood glucose cut-off value. In addition, a comparison of the frequencies of maternal and neonatal complications supports the validity of the new criteria. These findings should be taken into consideration by decision-makers in Oman when planning antenatal and postnatal services.

Hyperglycemia at 1h-OGTT in Pregnancy: A Reliable Predictor of Metabolic Outcomes?

Gestational diabetes mellitus (GDM) is associated with a high risk of developing type 2 diabetes (T2DM) and cardiovascular disease (CVD). Identifying among GDM women those who are at high risk may help prevent T2DM and, possibly CVD. Several studies have shown that in women with GDM, hyperglycemia at 1 h during an oral glucose tolerance test (OGTT) (1-h PG) is not only associated with an increase in adverse maternal and perinatal outcomes but is also an independent predictor of T2DM. Interestingly, also in pregnant women who did not meet the criteria for a GDM diagnosis, 1-h PG was an independent predictor of postpartum impaired insulin sensitivity and beta-cell dysfunction. Moreover, maternal 1- and 2-h PG levels have been found to be independently associated with insulin resistance and impaired insulin secretion also during childhood. There is evidence that hyperglycemia at 1h PG during pregnancy may identify women at high risk of future CVD, due to its association with an unfavorable CV risk profile, inflammation, arterial stiffness and endothelial dysfunction. Overall, hyperglycemia at 1h during an OGTT in pregnancy may be a valuable prediction tool for identifying women at a high risk of future T2DM, who may then benefit from therapeutic strategies aimed at preventing cardiovascular outcomes.

2. Classification and Diagnosis of Diabetes: Standards of Medical Care in Diabetes-2021

The American Diabetes Association (ADA) "Standards of Medical Care in Diabetes" includes the ADA's current clinical practice recommendations and is intended to provide the components of diabetes care, general treatment goals and guidelines, and tools to evaluate quality of care. Members of the ADA Professional Practice Committee, a multidisciplinary expert committee (https://doi.org/10.2337/dc21-SPPC), are responsible for updating the Standards of Care annually, or more frequently as warranted. For a detailed description of ADA standards, statements, and reports, as well as the evidence-grading system for ADA's clinical practice recommendations, please refer to the Standards of Care Introduction (https://doi.org/10.2337/dc21-SINT). Readers who wish to comment on the Standards of Care are invited to do so at professional.diabetes.org/SOC.

Genetic Loci and Physiologic Pathways Involved in Gestational Diabetes Mellitus Implicated Through Clustering

Hundreds of common genetic variants acting through distinguishable physiologic pathways influence the risk of type 2 diabetes (T2D). It is unknown to what extent the physiology underlying gestational diabetes mellitus (GDM) is distinct from that underlying T2D. In this study of >5,000 pregnant women from three cohorts, we aimed to identify physiologically related groups of maternal variants associated with GDM using two complementary approaches that were based on Bayesian nonnegative matrix factorization (bNMF) clustering. First, we tested five bNMF clusters of maternal T2D-associated variants grouped on the basis of physiology outside of pregnancy for association with GDM. We found that cluster polygenic scores representing genetic determinants of reduced β-cell function and abnormal hepatic lipid metabolism were associated with GDM; these clusters were not associated with infant birth weight. Second, we derived bNMF clusters of maternal variants on the basis of pregnancy physiology and tested these clusters for association with GDM. We identified a cluster that was strongly associated with GDM as well as associated with higher infant birth weight. The effect size for this cluster's association with GDM appeared greater than that for T2D. Our findings imply that the genetic and physiologic pathways that lead to GDM differ, at least in part, from those that lead to T2D.

Assessment of the association between the polymorphism rs1256031 of the estrogen receptor β gene and GDM susceptibility

Estrogen has an important role in regulating glucose homeostasis, and existing evidence indicates that it might be involved in the development of hyperglycemia in pregnancy. It mediates its effect through estrogen receptors including the nuclear receptor ERβ encoded by ESR2. The association between the ESR2 polymorphism rs1256031 and GDM susceptibility has not been investigated yet. This study aimed to evaluate the relationship between rs1256031 and GDM risk in Chinese population. A total of 241 GDM patients and 139 healthy pregnant women were recruited for this study. The rs1256031 genotype was examined by time-of-flight mass spectrometry and the association between rs1256031 and GDM susceptibility was assessed by binary logistic regression in three different genetic models. The polymorphism rs1256031 was not associated with GDM susceptibility in additive [OR (95% CI) = 0.871 (0.453,1.675); P = 0.680], dominant [OR (95% CI) = 0.908 (0.495,1.665); P = 0.755] or recessive [OR (95% CI) = 0.912 (0.591,1.408); P = 0.677] models after adjusting for confounding factors. We observed no association between the polymorphism rs1256031 in the ESR2 gene and GDM susceptibility in Chinese pregnant women.

Genetic Studies of Gestational Diabetes and Glucose Metabolism in Pregnancy

PURPOSE OF REVIEW

In this review, we summarize studies investigating genetics of gestational diabetes mellitus (GDM) and glucose metabolism in pregnancy. We describe these studies in the context of the larger body of literature on type 2 diabetes (T2D) and glycemic trait genomics.

RECENT FINDINGS

We reviewed 23 genetic association studies for GDM and performed a meta-analysis, which revealed variants at eight T2D loci significantly associated with GDM after the Bonferroni correction. These studies suggest that GDM and T2D share a number of genetic risk loci. Only two unbiased genome-wide association studies (GWASs) have successfully revealed genetic associations for GDM and related glycemic traits in pregnancy. A GWAS for GDM in Korean women identified two loci (near CDKAL1 and MTNR1B) known to be associated with T2D, though the association of the MTNR1B locus with GDM appears to be stronger than that for T2D. A multi-ethnic GWAS for glycemic traits in pregnancy identified two novel loci (near HKDC1 and BACE2) which appear to be associated with post-load glucose and fasting c-peptide specifically in pregnant women. There are ongoing efforts to use this genetic information, in the form of polygenic scores, to predict risk of GDM and postpartum T2D. The body of literature examining genetic associations with GDM is limited, especially when compared to the available literature on T2D and glycemic trait genomics. Additional genetic discovery for glucose metabolism in pregnant women will require larger pregnancy cohorts and international collaborative efforts. Studies on the clinical implications of these findings are also warranted.

Defining Heterogeneity Among Women With Gestational Diabetes Mellitus

Attention to precision medicine in type 2 diabetes (T2D) has provided two favored approaches to subclassifying affected individuals and parsing heterogeneity apparent in this condition: phenotype-based and genotype-based. Gestational diabetes mellitus (GDM) shares phenotypic characteristics with T2D. However, unlike T2D, GDM emerges in the setting of profound pregnancy-related physiologic changes in glucose metabolism. T2D and GDM also share common genetic architecture, but there are likely to be unique genetic influences on pregnancy glycemic regulation that contribute to GDM. In this Perspective, we describe efforts to decipher heterogeneity in T2D and detail how we and others are applying approaches developed for T2D to the study of heterogeneity in GDM. Emerging results reveal the potential of phenotype- and genotype-based subclassification of GDM to deliver the promise of precision medicine to the obstetric population.

The impact of educational attainment on the occurrence of gestational diabetes mellitus in two successive pregnancies of Finnish primiparous women: a population-based cohort study

AIMS

To assess the impact of educational attainment on the occurrence and recurrence of gestational diabetes mellitus (GDM) in two successive pregnancies in primiparous women.

METHODS

This is a population-based observational cohort study including all 2347 Finnish women without previously diagnosed diabetes, aged ≥ 20 years from the city of Vantaa, Finland, who gave birth to their first and second child between 2009 and 2015. National registries provided data on study participants. We divided the population into four groups according to the presence of GDM in the two pregnancies (GDM-/-, n = 1820; GDM-/+, n = 223; GDM+/-, n = 113; GDM+/+, n = 191).

RESULTS

The occurrence of GDM in the first pregnancy was 13.0% (n = 304) and 17.6% (n = 414) in the second. The recurrence rate of GDM was 62.8%. The four groups did not differ in relation to educational attainment (p = 0.11). In multinomial regression analysis, educational attainment protected from GDM in the second pregnancy [relative risk ratio 0.93 (95% confidence interval (CI) 0.86-0.99) per year of schooling for being GDM-/+ compared with GDM-/-]. In multivariate logistics models, prepregnancy body mass index at the first pregnancy [odds ratio (OR) 1.53 per 1-standard deviation (SD) (95% CI 1.22-1.91)], first-born birth weight z-score [OR 1.30 per 1-SD (95% CI 1.00-1.67)], and inter-pregnancy weight change [OR 1.66 per 1-SD (95% CI 1.27-2.16)], but not educational attainment, predicted recurrence of GDM.

CONCLUSIONS

The recurrence rate of GDM was high. Education protected from novel GDM in the second pregnancy, but was not associated with GDM recurrence.

Pathophysiology of gestational diabetes mellitus in lean Japanese pregnant women in relation to insulin secretion or insulin resistance

To determine the pathophysiology of gestational diabetes (GDM) in lean Japanese pregnant women in relation to insulin secretion or insulin resistance. The 75-g oral glucose tolerance test (OGTT) was performed in case of positive results of universal screening of a 50-g glucose challenge test at 24-28 weeks' gestation in Japanese pregnant women. These women were treated in our hospital between 2012 and 2016. Among these women, 30 with a body mass index of < 18.5 kg/m² were selected as lean subjects. Nine women were diagnosed with GDM (GDM group) and the remaining 21 had normal glucose tolerance (control group). For evaluating insulin secretion or resistance, the following parameters were compared between the two groups together with a family history of diabetes mellitus (DM) among first-degree relatives: (1) plasma glucose and immnunoreactive insulin (IRI) levels after glucose loading, (2) insulinogenic index (I.I), (3) homeostasis model assessment of β-cell function (HOMA-β), (4) homeostasis model assessment of insulin resistance (HOMA-IR), and (5) insulin sensitivity index (ISI) composite. The percentage of having a family history of DM was significantly higher in the GDM group (3/9, 33.3%) than in the control group (0/21, 0.0%, P < 0.001). Serum glucose levels at 30, 60, and 120 min after glucose loading were significantly higher in the GDM group than in the control group (all P < 0.05). IRI levels at 60 and 120 min were significantly higher in the GDM group than in the control group (both P < 0.05), and they showed persistent insulin secretion patterns. Values of the I.I. and ISI composite were significantly lower in the GDM group than in the control group (both P < 0.05), with no differences in HOMA-β, HOMA-IR and HbA1c levels between the groups. Lean Japanese pregnant women with GDM have impaired β-cell function, which is in part associated with hereditary traits.

Secretagogin is Related to Insulin Secretion but Unrelated to Gestational Diabetes Mellitus Status in Pregnancy

Secretagogin (SCGN) is a calcium binding protein related to insulin release in the pancreas. Although SCGN is not co-released with insulin, plasma concentrations have been found to be increased in type 2 diabetes mellitus patients. Until now, no study on SCGN levels in pregnancy or patients with gestational diabetes mellitus (GDM) has been published. In 93 women of a high-risk population for GDM at the Medical University of Vienna, secretagogin levels of 45 GDM patients were compared to 48 women with a normal glucose tolerance (NGT). Glucose tolerance, insulin resistance and secretion were assessed with oral glucose tolerance tests (OGTT) between the 10th and 28th week of gestation (GW) and postpartum. In all women, however, predominantly in women with NGT, there was a significant positive correlation between SCGN levels and Stumvoll first (r_p = 0.220, p = 0.032) and second phase index (r_p = 0.224, p = 0.028). SCGN levels were not significantly different in women with NGT and GDM. However, SCGN was higher postpartum than during pregnancy (postpartum: 88.07 ± 35.63 pg/mL; pregnancy: 75.24 ± 37.90 pg/mL, p = 0.004). SCGN was directly correlated with week of gestation (r_p = 0.308; p = 0.021) and triglycerides (r_p = 0.276; p = 0.038) in women with GDM. Therefore, SCGN is related to insulin secretion and hyperinsulinemia during pregnancy; however, it does not display differences between women with NGT and GDM.

Progression to type 2 diabetes in women with a known history of gestational diabetes: systematic review and meta-analysis

OBJECTIVE

To estimate and compare progression rates to type 2 diabetes mellitus (T2DM) in women with gestational diabetes mellitus (GDM) and healthy controls.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

Medline and Embase between January 2000 and December 2019, studies published in English and conducted on humans.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Observational studies investigating progression to T2DM. Inclusion criteria were postpartum follow-up for at least 12 months, incident physician based diagnosis of diabetes, T2DM reported as a separate outcome rather than combined with impaired fasting glucose or impaired glucose tolerance, and studies with both a group of patients with GDM and a control group.

RESULTS

This meta-analysis of 20 studies assessed a total of 1 332 373 individuals (67 956 women with GDM and 1 264 417 controls). Data were pooled by random effects meta-analysis models, and heterogeneity was assessed by use of the I² statistic. The pooled relative risk for the incidence of T2DM between participants with GDM and controls was estimated. Reasons for heterogeneity between studies were investigated by prespecified subgroup and meta-regression analyses. Publication bias was assessed by funnel plots and, overall, studies were deemed to have a low risk of bias (P=0.58 and P=0.90). The overall relative risk for T2DM was almost 10 times higher in women with previous GDM than in healthy controls (9.51, 95% confidence interval 7.14 to 12.67, P<0.001). In populations of women with previous GDM, the cumulative incidence of T2DM was 16.46% (95% confidence interval 16.16% to 16.77%) in women of mixed ethnicity, 15.58% (13.30% to 17.86%) in a predominantly non-white population, and 9.91% (9.39% to 10.42%) in a white population. These differences were not statistically significant between subgroups (white v mixed populations, P=0.26; white v non-white populations, P=0.54). Meta-regression analyses showed that the study effect size was not significantly associated with mean study age, body mass index, publication year, and length of follow-up.

CONCLUSIONS

Women with a history of GDM appear to have a nearly 10-fold higher risk of developing T2DM than those with a normoglycaemic pregnancy. The magnitude of this risk highlights the importance of intervening to prevent the onset of T2DM, particularly in the early years after pregnancy.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42019123079.

Elevated Glucose and Insulin Levels Decrease DHA Transfer across Human Trophoblasts via SIRT1-Dependent Mechanism

Gestational diabetes mellitus (GDM) results in reduced docosahexaenoic acid (DHA) transfer to the fetus, likely due to placental dysfunction. Sirtuin-1 (SIRT1) is a nutrient sensor and regulator of lipid metabolism. This study investigated whether the high glucose and insulin condition of GDM regulates DHA transfer and expression of fatty acid transporters and if this effect is related to SIRT1 expression and function. Syncytialized primary human trophoblasts were treated with and without glucose (25 mmol/L) and insulin (10^-7 mol/L) for 72 h to mimic the insulin-resistance conditions of GDM pregnancies. In control conditions, DHA transfer across trophoblasts increased in a time- and dose-dependent manner. Exposure to GDM conditions significantly decreased DHA transfer, but increased triglyceride accumulation and fatty acid transporter expression (CD36, FABP3, and FABP4). GDM conditions significantly suppressed SIRT1 mRNA and protein expression. The SIRT1 inhibitor decreased DHA transfer across control trophoblasts, and recombinant SIRT1 and SIRT1 activators restored the decreased DHA transport induced by GDM conditions. The results demonstrate a novel role of SIRT1 in the regulation of DHA transfer across trophoblasts. The suppressed SIRT1 expression and the resultant decrease in placental DHA transfer caused by high glucose and insulin levels suggest new insights of molecular mechanisms linking GDM to fetal DHA deficiency.

Diet and Nutritional Interventions with the Special Role of Myo-Inositol in Gestational Diabetes Mellitus Management. An Evidence-Based Critical Appraisal

BACKGROUND

Gestational Diabetes Mellitus (GDM), defined as glucose intolerance with onset or first recognition during pregnancy, represents one of the most common maternal-fetal complications during pregnancy and it is associated with poor perinatal outcomes. To date, GDM is a rising condition over the last decades coinciding with the ongoing epidemic of obesity and Type 2 Diabetes Mellitus (T2DM).

OBJECTIVE

The aim of this review is to discuss the role of diet and nutritional interventions in preventing GDM with the explanation of the special role of myo-inositol (MI) in this matter.

METHODS

We performed an overview of the most recent literature data on the subject with particular attention to the effectiveness of diet and nutritional interventions in the prevention of GDM with the special role of MI.

RESULTS

Nutritional intervention and physical activity before and during pregnancy are mandatory in women affected by GDM. Moreover, the availability of insulin-sensitizers such as different forms of inositol has dramatically changed the scenario, allowing the treatment of several metabolic diseases, such as those related to glucose dysbalance. Although the optimal dose, frequency, and form of MI administration need to be further investigated, diet supplementation with MI appears to be an attractive alternative for the GDM prevention as well as for the reduction of GDM-related complications.

CONCLUSIONS

More studies should be conducted to prove the most effective nutritional intervention in GDM. Regarding the potential effectiveness of MI, further evidence in multicenter, randomized controlled trials is needed to draw firm conclusions.

The association between the rs4987105 of 5-lipoxygenase (ALOX5) gene and gestational glucose metabolism in Chinese population

Objective

The arachidonate 5-lipoxygenase (ALOX5) pathway has been investigated in diverse chronic inflammatory diseases including metabolic disorders. Recently, the ALOX5 polymorphism rs4987105 was identified to confer susceptibility to type 2 diabetes mellitus (T2DM), implicating its role in regulating glucose homeostasis. Gestational diabetes mellitus (GDM) shares similar pathogenic mechanism with T2DM. Thus, we aimed to evaluate the association between rs4987105 and gestational glucose metabolism in Chinese pregnant women.

Results

A total of 380 unrelated Chinese pregnant women including 241 GDM patients and 139 controls were included in this study. The genotypes of rs4987105 were examined by the Agena MassARRAY iPLEX platform, the association between rs4987105 and fasting plasma glucose (FPG) levels at 24–28 gestational weeks was evaluated using different statistical methods. We found that carriers of rs4987105 CT/TT genotypes exhibited significantly lower FPG levels (P = 0.011). In addition, we observed a significant association between rs4987105 and FPG levels after adjusting confounding variables in the linear regression analysis using dominant genetic model (b = − 0.218; P = 0.01). The present study for the first time reported that the rs4987105 of 5-lipoxygenase (ALOX5) gene was associated with gestational glucose metabolism in Chinese pregnant women.

Antipsychotic Exposure in Pregnancy and the Risk of Gestational Diabetes: A Systematic Review and Meta-analysis

BACKGROUND

We have limited knowledge about the effects of antipsychotic exposure on the development of gestational diabetes mellitus (GDM). Aim of this study is to perform a systematic review and meta-analysis to assess GDM risk associated with antipsychotic exposure in pregnancy.

METHODS

Systematic literature search was performed using PubMed, Science Direct, Scopus, and Web of Science databases up to August 22, 2018. No restrictions to language or date were applied. Randomized, controlled trials, case-control, or cohort studies reporting GDM risk in antipsychotic-exposed, healthy controls or antipsychotic-ceased patients were included in the meta-analysis. The primary outcomes were study defined GDM, including number of events, odds ratios, and/or risk ratios (RR) with confidence intervals (CI).

RESULTS

Ten studies were included in the meta-analysis. The total number of subjects was 6213 for the antipsychotic-exposed group, 6836 for antipsychotic-ceased control group, and 1 677 087 for the healthy control group. Compared with the healthy controls, the unadjusted cumulative RR for GDM associated with antipsychotic use was 1.63 (95% CI = 1.20-2.22). Adjusted risk for GDM was significantly higher in antipsychotic exposure group than in healthy controls (RR = 1.30, 95% CI = 1.023-1.660). The adjusted RR for GDM was similar between the antipsychotic-exposed group and the antipsychotic-ceased group (RR = 0.78, 95% CI = 0.281-2.164). No significant association was found between study quality, smoking, alcohol use, gestational age, and cumulative GDM risk.

DISCUSSION

Our results indicate an increased risk of GDM with antipsychotic exposure in pregnant women, who may benefit from close pregnancy monitoring, early testing for GDM, targeting modifiable risk factors, and lifestyle modifications.

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.

The Role of Dietary Carbohydrates in Gestational Diabetes

Gestational diabetes (GDM) is hyperglycemia that is recognized for the first time during pregnancy. GDM is associated with a wide range of short- and long-term adverse health consequences for both mother and offspring. It is a complex disease with a multifactorial etiology, with disturbances in glucose, lipid, inflammation and gut microbiota. Consequently, its management is complex, requiring patients to self-manage their diet, lifestyle and self-care behaviors in combination with use of insulin. In addition to nutritional recommendations for all pregnant women, special attention to dietary carbohydrate (CHO) amount and type on glucose levels is especially important in GDM. Dietary CHO are diverse, ranging from simple sugars to longer-chain oligo- and poly- saccharides which have diverse effects on blood glucose, microbial fermentation and bowel function. Studies have established that dietary CHO amount and type can impact maternal glucose and nutritional recommendations advise women with GDM to limit total intake or choose complex and low glycemic CHO. However, robust maternal and infant benefits are not consistently shown. Novel approaches which help women with GDM adhere to dietary recommendations such as diabetes-specific meal replacements (which provide a defined and complete nutritional composition with slowly-digested CHO) and continuous glucose monitors (which provide unlimited monitoring of maternal glycemic fluctuations) have shown benefits on both maternal and neonatal outcomes. Continued research is needed to understand and develop tools to facilitate patient adherence to treatment goals, individualize interventions and improve outcomes.

2. Classification and Diagnosis of Diabetes: Standards of Medical Care in Diabetes-2020

The American Diabetes Association (ADA) "Standards of Medical Care in Diabetes" includes the ADA's current clinical practice recommendations and is intended to provide the components of diabetes care, general treatment goals and guidelines, and tools to evaluate quality of care. Members of the ADA Professional Practice Committee (https://doi.org/10.2337/dc20-SPPC), a multidisciplinary expert committee, are responsible for updating the Standards of Care annually, or more frequently as warranted. For a detailed description of ADA standards, statements, and reports, as well as the evidence-grading system for ADA's clinical practice recommendations, please refer to the Standards of Care Introduction (https://doi.org/10.2337/dc20-SINT). Readers who wish to comment on the Standards of Care are invited to do so at professional.diabetes.org/SOC.

Mechanism associated with aberrant lncRNA MEG3 expression in gestational diabetes mellitus

Gestational diabetes mellitus (GDM) is a common metabolic condition during pregnancy. Long non-coding RNAs (lncRNAs) have been found to seve critical roles in GDM development; however, the role of lncRNA maternally expressed gene 3 (MEG3) in GDM remains unclear. Therefore, the aim of the present study was to investigate the expression and role of MEG3 in GDM, and to further explore the underlying mechanism. The levels of lncRNA MEG3 in the blood and placental villous tissues of pregnant women with GDM was measured using reverse transcription-quantitative PCR. Bioinformatics analysis and dual luciferase reporter assays were performed to investigate the association between lncRNA MEG3 and microRNA (miR)-345-3p. Transfection was subsequently performed on HTR-8/SVneo cells, a human chorionic trophoblast cell line, to assess the role of lncRNA MEG3 in GDM. In particular, cell viability, cellular migratory/invasive ability and cell apoptosis were analyzed using MTT assay, Transwell assay and flow cytometry, respectively. Compared with pregnant women without GDM, lncRNA MEG3 levels were significantly elevated in the blood and placental villous tissues of GDM pregnant women. miR-345-3p was identified to be a direct target of lncRNA MEG3 using dual luciferase reporter assay, which was found to be reduced in pregnant women with GDM. Further analysis demonstrated that lncRNA MEG3 overexpression significantly inhibited HTR-8/SVneo cell viability, and prevented cell migration and invasion in addition to inducing cell apoptosis. In contrast, lncRNA MEG3 knockdown significantly enhanced HTR-8/SVneo cell viability, promoted cell migration/invasion and reduced cell apoptosis. Inhibiting miR-345-3p expression negated all the observed physiological effects of lncRNA MEG3 knockdown on HTR-8/SVneo cells. In conclusion, lncRNA MEG3 levels were abnormally upregulated in GDM, which participated in the development and progression of GDM by regulating human chorionic trophoblast cell physiology. Therefore, lncRNA MEG3 may be a potential diagnostic and therapeutic target for GDM.

A Prospective Study of Early Pregnancy Essential Metal(loid)s and Glucose Levels Late in the Second Trimester

CONTEXT

Studies suggest many essential trace metal(loid)s are involved in glucose metabolism, but the associations among pregnant women are unclear.

OBJECTIVE

To assess associations between early pregnancy plasma zinc, selenium, copper, and molybdenum levels and blood glucose levels later in the second trimester.

DESIGN

The Eunice Kennedy Shriver National Institute of Child Health and Human Development Fetal Growth Studies‒Singleton Cohort is a prospective cohort study conducted between July 2009 and January 2013.

SETTING

Twelve academic research hospitals in the United States.

PATIENTS

A total of 1857 multiracial, nonobese, healthy women.

MAIN OUTCOME MEASURE

Blood glucose levels from 1-hour 50-g gestational load test (GLT) at 24 to 28 weeks of gestation.

RESULTS

Higher concentrations of first-trimester copper were associated with higher glucose levels from the GLT (i.e., every 50% increase in copper concentration was related to 4.9 mg/dL higher glucose level; 95% CI: 2.2, 7.5 mg/dL) adjusted for maternal sociodemographic characteristics and reproductive history. In contrast, every 50% increase in molybdenum concentration was associated with 1.2 mg/dL lower mean glucose level (95% CI: -2.3, -0.1 mg/dL). The magnitude of these associations was greater at the upper tails of glucose level distribution based on quantile regressions of the 10th, 50th, and 90th percentiles.

CONCLUSIONS

Higher copper and lower molybdenum concentrations could increase the risk of glucose dysregulation during pregnancy, with women at higher risk of gestational diabetes mellitus potentially affected to a greater extent. Further work is needed to understand the mechanisms involved with early pregnancy essential metal(loid)s to inform clinical diagnosis and prevention of glucose intolerance during pregnancy.

Research Gaps in Gestational Diabetes Mellitus: Executive Summary of a National Institute of Diabetes and Digestive and Kidney Diseases Workshop

The National Institute of Diabetes and Digestive and Kidney Diseases convened a workshop on research gaps in gestational diabetes mellitus (GDM) with a focus on 1) early pregnancy diagnosis and treatment and 2) pharmacologic treatment strategies. This article summarizes the proceedings of the workshop. In early pregnancy, the appropriate diagnostic criteria for the diagnosis of GDM remain poorly defined, and an effect of early diagnosis and treatment on the risk of adverse outcomes has not been demonstrated. Despite many small randomized controlled trials of glucose-lowering medication treatment in GDM, our understanding of medication management of GDM is incomplete as evidenced by discrepancies among professional society treatment guidelines. The comparative effectiveness of insulin, metformin, and glyburide remains uncertain, particularly with respect to long-term outcomes. Additional topics in need of further research identified by workshop participants included phenotypic heterogeneity in GDM and novel and individualized treatment approaches. Further research on these topics is likely to improve our understanding of the pathophysiology and treatment of GDM to improve both short- and long-term outcomes for mothers and their children.

Perinatal Outcomes Among Different Asian Groups With Gestational Diabetes Mellitus in Ontario: A Cohort Study

OBJECTIVE

The aim of this study was to determine whether perinatal outcomes differ between Caucasian and Asian subgroups of women with gestational diabetes mellitus (GDM) through use of standard vs ethnicity-specific birthweight curves.

METHODS

This retrospective cohort study included 537 women with GDM, within the ethnically diverse province of Ontario, Canada. Study outcomes included large-for-gestational-age (LGA) and small-for-gestational-age (SGA) birthweights in newborns of women from prevalent Asian ethnic groups compared with newborns of Caucasian women. Odds ratios were adjusted for maternal age, parity, prepregnancy body mass index, gestational weight gain and insulin use in pregnancy.

RESULTS

Of the 537 women participing in the study, 228 (35.8%) were Caucasian, 109 (17.1%) South Asian, 141 (22.1%) East Asian and 59 (9.3%) Filipino. Using standard birthweight curves, compared with Caucasian women, the risk of LGA was lower among South Asian (adjusted odds ratio [aOR], 0.065; 95% confidence interval [CI], 0.01 to 0.49) and East Asian (aOR, 0.36; 95% CI, 0.14 to 0.95) women. The aOR for SGA was notably higher among South Asian women (aOR, 2.96; 95% CI, 1.24 to 7.09). Significant effects were not seen among Filipino women. Use of ethnicity-specific birthweight curves largely attenuated these associations, except for LGA in South Asian mothers (aOR, 0.27; 95% CI, 0.09 to 0.81).

CONCLUSION

South Asian women with GDM are at lower risk of having an LGA newborn, even after accounting for maternal risk factors or the use of an ethnicity-specific birthweight curve.

Association between retinol-binding protein 4 concentrations and gestational diabetes mellitus (A1GDM and A2GDM) in different pregnancy and postpartum periods

Background

Gestational diabetes mellitus (GDM) can cause severe adverse effects on fetal and neonatal outcomes. The following study investigates the relationship between retinol-binding protein 4 (RBP4) and GDM in pregnant women with different grades (A1 and A2) and different gestational weeks.

Methods

In this retrospective study, 194 GDM patients (GDM group) and 67 normal glucose tolerance pregnant women (control group) were enrolled from 2014 to 2017. Elbow venous blood samples were collected from all subjects. Enzyme electrode method and enzyme linked immunosorbent assay (ELISA) were used for fasting plasma glucose (FPG) and RBP4/insulin levels (FINS) analysis, respectively.

Results

At middle pregnancy and late stage, FINS, insulin resistance index (HOMA-IR) and RBP4 were all significantly higher in the GDM group compared to control group (P<0.05). Higher HOMA-IR and RBP4 levels, and lower levels of FPG were observed at late stage than those middle pregnancy in the GDM group (P<0.05). Moreover, FINS and RBP4 gradually decreased from middle pregnancy and late stage after delivery in the GDM group. Levels of FINS and RBP4 in postpartum GDM group were higher than those in normal control group (P<0.05). The optimal cut-off value of RBP4 at middle pregnancy diagnostic GDM was 34.84 µg/mL with sensitivity of 79.4% and specificity of 79.1%. The OGTT0h, 2h in A2GDM group was higher than that in A1GDM group, but there was no difference in OGTT1h, age and FINS, RBP4 in both A1GDM and A2GDM group.

Conclusions

RBP4 is closely related to GDM, and its levels increases with the increase of gestational weeks, which may reflect the development of insulin resistance in GDM. RBP4 suggests that the impaired insulin function of GDM in pregnant women is still difficult to recover in the short term after delivery. Compared with OGTT1h, the increase in OGTT0h and 2h levels during middle pregnancy is more helpful for predicting the risk of developing A2GDM at late stage.

Chorionic and amniotic membrane-derived stem cells have distinct, and gestational diabetes mellitus independent, proliferative, differentiation, and immunomodulatory capacities

Placental membrane-derived mesenchymal stem cells (MSCs), with the advantages of being non-invasive and having fewer ethical issues, are a promising source for cell therapy. Gestational diabetes (GDM) alters the uterine environment and may affect the therapeutic potential of MSCs derived from placenta. Therefore, we evaluated the biological properties of amniotic (AMSCs) and chorionic membrane MSCs (CMSCs) from human GDM placenta in order to explore their therapeutic potential. In comparison of GDM-/Healthy- CMSCs and AMSCs, the immunophenotypes and typical stellate morphology of MSC were similar in CMSCs irrespective of disease state while the MSC morphology in GDM-AMSCs was less evident. GDM- and Healthy- CMSCs displayed an enhanced proliferation rate and tri-lineage differentiation capacity compared with AMSCs. Notably, GDM-CMSCs had a significantly increased adipogenic ability than Healthy-CMSCs accompanied by increased transcriptional responsiveness of PPARγ and ADIPOQ induction. The secretome effect of Healthy- and GDM- CMSCs/AMSCs by using conditioned media and coculture experiments, suggests that GDM- and Healthy- CMSCs provided an equivalent immunoregulatory effect on suppressing T-cells activation but a reduced effect of GDM-CMSCs on macrophage regulation. However, Healthy- and GDM- CMSCs displayed a superior immunomodulatory capacity in regulation of both T-cells and macrophages than AMSCs. In summary, we highlight the importance of the maternal GDM intrauterine environment during pregnancy and its impact on CMSCs/AMSCs proliferation ability, CMSCs adipogenic potential, and macrophage regulatory capacity.

The effectiveness of low trans-fatty acids dietary pattern in pregnancy and the risk of gestational diabetes mellitus

Background:

Gestational diabetes mellitus (GDM) is a common disorder in pregnancy. The association of trans fatty acids (TFA) intake and risk of GDM have been reported; It remains unclear whether dietary TFA can influence GDM risk. We examined the effect of low TFA dietary intakes during pregnancy on risk of GDM.

Methods:

This randomized controlled trial was performed on 800 pregnant women who were randomly divided into 393 intervention and 407 comparison groups with gestational age ≥7 weeks. In the intervention group, the diet of pregnant women was designed in such a way that their daily intake of TFA content was less than1% but in control group, the daily intake of TFA content was not changed. The dietary intake was assessed using a 24-hour dietary recall questionnaire for three non-consecutive days at the beginning of the pregnancy before week 7, and at 13, 25 and 35 weeks. Diagnosis of GDM was performed using a 3-hour glucose tolerance test with 100 g glucose at 24-28 weeks of gestation.

Results:

14 women in the intervention group (5%) and 31 women in the control group (8%) were diagnosed with GDM. Chi-square test did not show any significant difference between two groups (P=0.08). Cox model was used and the variables were examined in four multivariate models that none of the modals showed a statistically significant difference between the two groups regarding the incidence of GDM.

Conclusion:

It seems that the diet with low trans-fatty acid content has no effect on the incidence of GDM.

The association between intake of dietary lycopene and other carotenoids and gestational diabetes mellitus risk during mid-trimester: a cross-sectional study

This study aimed to determine whether increased carotenoids intake was associated with reduced risk of gestational diabetes mellitus (GDM). We performed a cross-sectional analysis using data from Tongji Maternal and Child Health Cohort study. The dietary carotenoids intake of 1978 pregnant women was assessed using a researcher-administered FFQ before undertaking an oral glucose tolerance test at 24–28 weeks. Multivariate logistic and linear regression analyses were used to obtain the effect estimates. Participants in the highest quartile of lycopene intake showed a lower risk of GDM (OR 0·50; 95 % CI 0·29, 0·86; Pfor trend = 0·007) compared with those in the lowest quartile; each 1 mg increase in lycopene consumption was associated with a 5 % (95 % CI 0·91, 0·99; Pfor trend = 0·020) decrease in GDM risk. No significant association was found between α-carotene, β-carotene, β-cryptoxanthin, lutein/zeaxanthin intake and GDM risk. Multiple linear regression analysis suggested an inverse association between lycopene intake and fasting blood glucose (FBG) (Pfor trend < 0·001); each 1 mg increase in lycopene intake was associated with 0·005 (95 % CI 0·002, 0·007; Pfor trend < 0·001) mmol/l decrease in FBG. Interaction analysis indicated consistent effect on each age or pre-BMI subgroup; however, a stronger protective effect of lycopene intake against GDM was observed among primigravid women (OR 0·20; 95 % CI 0·07, 0·55 in the highest v. the lowest quartile of intake; Pfor interaction = 0·036). In conclusion, dietary lycopene intake was mainly assumed via reducing FBG to decrease GDM risk, and the protection was relatively increased among primigravid women.

Gestational diabetes mellitus and macrosomia predispose to diabetes in the Lebanese population

AIMS

The Middle East has the fastest rising rate of Type 2 Diabetes Mellitus (T2DM) worldwide, with Lebanon having 15.8% of its population affected. This study aims at studying Polycystic Ovarian Syndrome (PCOS), Gestational Diabetes Mellitus (GDM), and macrosomia as risk factors of T2DM in Lebanon. Such epidemiological and statistical study has never been conducted before in the Middle East region and would be useful for clinical diagnosis.

METHODS

Our cohort is comprised of 1453 Lebanese individuals, with 897 controls and 556 patients. We tested the correlation between T2DM and the covariates GDM, PCOS, and macrosomia independently. We conducted multinomial logistic regression and cross tabulations with T2DM as an outcome.

RESULTS

The results showed a significant association of the independent factors GDM and macrosomia with T2DM. The risk of having T2DM was increased by 4.192 times with the GDM, and by 2.315 times with macrosomia respectively.

CONCLUSION

In conclusion, GDM and macrosomia, but not PCOS, are significant risk factors for T2DM in our Lebanese cohort. Our results, reported for the first time in the Middle East, present insights into risk factors management and disease prevention.