Is there a causal association between gestational diabetes mellitus and immune mediators? A bidirectional Mendelian randomization analysis.

Background: Diabetes that only appears or is diagnosed during pregnancy is referred to as gestational diabetes mellitus (GDM). The maternal physiological immune profile is essential for a positive pregnancy outcome. However, the causal relationship between GDM and immunophenotypes is not fully defined. Methods: Based on the high-density genetic variation data at the genome-wide level, we evaluated the logical associations between 731 specific immune mediators and GDM using bidirectional Mendelian randomization (MR). The inverse variance weighted (IVW) was the main method employed for MR analysis. We performed multiple methods to verify the robustness and dependability of the MR results, and sensitivity measures were applied to rule out potential heterogeneity and horizontal pleiotropy. Results: A substantial causal association between several immune mediators and GDM was detected. After FDR testing, HLA DR++ monocyte %leukocyte and HLA DR on plasmacytoid DC were shown to increase the risk of GDM; in contrast, CD127 on CD28+ CD45RA+ CD8br and CD19 on PB/PC were shown to attenuate the effect of GDM. Moreover, the progression of GDM has been shown to decrease the maternal levels of CD39+ activated Treg AC, CD39+ activated Treg %CD4 Treg, CD39+ resting Treg AC, CD39+ resting Treg %CD4 Treg, and CD39+ CD8BR %T cell. Conclusions: Our findings support a possible causal association between GDM and various immunophenotypes, thus facilitating the provision of multiple options for preventive recognition as well as for the diagnostic and therapeutic management of GDM in clinical practice.

Immunomodulation of Ethyl pyruvate on gestational diabetes mellitus in Mice; The impact on Th17/Treg balance.

Gestational diabetes mellitus (GDM) is recognized as one of the most common diseases among pregnant women and inflammatory responses can be a major reason for its induction and development. T helper 17 (Th17)/regulatory T cells (Tregs) imbalance resulting in the increased levels of pro-inflammatory and decreased levels of anti-inflammatory cytokines has been showed as major mechanisms involved in the pathogenesis of GDM. There are various treatment options, but none of them are completely therapeutic. Ethyl pyruvate (EP) is a stable derivate of pyruvate that showed anti-oxidant and anti-inflammatory properties in an in-vivo and in-vitro models. To examine the therapeutic efficacy of EP in GDM, mice were mated and EP (100 mg/kg) was administered intraperitoneally to C57BL/6 mice. EP-treated mice exhibited improved symptoms of GDM by decreased blood glucose levels and body-weight and increased insulin levels and insulin sensitivity. Furthermore, EP could significantly attenuate the impairments to offspring, including birth size and birth weight. The inflammatory responses were also decreased by EP through regulating the production of Th17-related cytokines, such as interleukin (IL)- 17 and IL-21. The levels of other inflammatory cytokines were also inhibited, including IL-1ß, IL-6, and tumor necrosis factor (TNF)-α. In addition, it was found that EP increased the population of Tregs and Treg-related cytokines, IL-10 and transforming Growth Factor-ß TGF-ß, in GDM mice. In conclusion, EP could modulate GDM in mice and might be a potential therapeutic strategy candidate for the treatment of patients with GDM.

Characteristics and functions of memory regulatory T cells in normal pregnancy cycle and pregnancy complications.

Regulatory T cells (Tregs) are activated and expanded after exposure to fetal-specific (paternal) antigens. A proportion of Tregs differentiate into memory Tregs (mTregs), exhibiting immune memory function and exerting more potent immunosuppression than naive Tregs (nTregs). However, it is unclear how mTregs are regulated during normal and pathological pregnancies (e.g., gestational diabetes mellitus (GDM) and preeclampsia (PE)). In this study, PD-1, HLA-G, and HLA-DR expressions on memory CD4+ T cells, naive CD4+ T cells, Tregs, mTregs, and nTregs in healthy non-pregnant women (n=20), healthy first (n=20), second (n=20), and third-trimester women (n=20), postpartum women (n=20), GDM (n=20), and PE patients (n=20) were analyzed. The proportion of mTregs out of Tregs was increased (P<0.05) in the first trimester compared with that in non-pregnancy and reduced in the second and third trimesters. The proportions of PD-1+ Tregs and mTregs were significantly increased during the first trimester compared to those of non-pregnancy (P<0.01), reached their maximum in the second trimester. Moreover, the proportions of HLA-G+ memory CD4+ T cells, Tregs, and mTregs were increased in the first and second trimesters (P<0.01), reached their maximum in the third trimester. GDM patients were characterized by significantly lower percentages of PD-1+ and HLA-G+ mTregs (P<0.01), while PE patients were characterized by significantly lower percentages of HLA-G+ mTregs (P<0.01), compared with the healthy third-trimester women. In general, as demonstrated by this study, mTregs increase in number and enhance maternal-fetal immunoregulation during pregnancy, and their dysfunction can result in pregnancy complications such as GMD or PE.

Placental expression of inflammatory Galectin-12 is associated with gestational diabetes.

OBJECTIVES: Gestational diabetes mellitus (GDM) is a growing health concern. Since members of the galectin-family are identified to play a role in the pathogenesis of GDM, we determined galectin-12 as an essential protein due to its influence in lipolysis and inflammation processes. This study investigates the expression of galectin-12 in the placentas of women with GDM. STUDY DESIGN: The study population includes 40 expectant women suffering from GDM and 40 healthy controls. The expression of galectin-12 in the syncytiotrophoblast (SCT) and the extra villous trophoblast (EVT) of the placenta was analyzed by immunohistological staining and double immunofluorescence. Immunoreactivity Score (IRS) was used for evaluation. RESULTS: The results demonstrate a significant overexpression of galectin-12 in the nucleus of the SCT and the EVT of placentas with GDM compared to the healthy control group. Additionally, double immunofluorescence visualizes corresponding results with an overexpression of galectin-12 in the extra villous trophoblast of GDM placentas representing maternal cells. CONCLUSION: This study identifies galectin-12 to be associated with the process of gestational diabetes mellitus. These findings are in correspondence with the involvement of galectin-12 in inflammatory processes. Maternal BMI and male sex seem to be confounder for the expression of galectin-12 in the nuclear syncytiotrophoblast, but not in other parts of the investigated placental areas. Further investigations are necessary to verify the correlation between gestational diabetes mellitus and the expression of galectin-12 in the placenta and to further elucidate its distinct role.

Exposure to gestational diabetes mellitus increases subclinical inflammation mediated in part by obesity.

Gestational diabetes mellitus (GDM) is a frequent and serious complication of pregnancy, often associated with obesity. Metabolic dysfunction and metainflammation are evident in both obesity and GDM. In this cross-sectional study, we aimed at defining the direct contribution of the immune system in GDM, across the main metabolic tissues, specifically focussing on elucidating the roles of obesity and GDM to the clinical outcome. Using immunoassays and multicolour flow cytometry, cytokine profiles and immune cell frequencies were measured in maternal circulation and central metabolic tissues [placenta and visceral adipose tissue (VAT)] in GDM-diagnosed (n = 28) and normal glucose tolerant (n = 32) women undergoing caesarean section. Participants were sub-grouped as non-obese [body mass index (BMI) < 30 kg/m2] or obese (BMI ≥ 30 kg/m2). Unsupervised data analysis was performed on the flow cytometry data set to identify functional alterations. GDM obese participants had significantly elevated circulating IL-6 and IL-17A levels. GDM non-obese participants had elevated circulating IL-12p70, elevated placental IL-17A, and VAT IFN-γ production. Unsupervised clustering of immune populations across the three biological sites simultaneously, identified different NK- and T-cell phenotypes that were altered in NGT obese and GDM non-obese participants, while a classical tissue monocyte cluster was increased in GDM obese participants. In this study, there was significant evidence of subclinical inflammation, and significant alterations in clusters of NK cells, T cells, and tissue monocyte populations in GDM. While increased adiposity assimilates with increased inflammation in the non-pregnant state, this overt relationship may not be as evident during pregnancy and warrants further examination in future longitudinal studies.

Characterization of cord blood CD3+ TCRVα7.2+ CD161high T and innate lymphoid cells in the pregnancies with gestational diabetes, morbidly adherent placenta, and pregnancy hypertension diseases.

PROBLEM: Although pregnant women with gestational diabetes (GD), morbidly adherent placenta (MAP), and pregnancy hypertension (pHT) diseases lead to intrauterine growth restriction (IUGR), little is known about their effect on mucosal-associated invariant T (MAIT) and innate lymphoid cells (ILC) in the umbilical cord. This study aimed to quantify and characterize MAIT cells and ILCs in the cord blood of pregnant women with GD, MAP, and pHT diseases. METHOD OF STUDY: Cord blood mononuclear cells (CBMCs) were isolated by Ficoll-Paque gradient. CD3+ TCRVα7.2+ CD161high cells and ILC subsets were quantified by flow cytometry. CBMCs were stimulated with PMA/Ionomycin and Golgi Plug for 4 h and stained for IFN-γ, TNF-α, and granzyme B. The stained cells were analyzed on FACS ARIA III. RESULTS: Compared with healthy pregnancies, in the cord blood of the pHT group, elevated number of lymphocytes was observed. Moreover, the absolute number of IFN-γ producing CD4+ or CD4- subsets of CD3+ TCRVα7.2+ CD161high cells as well as those producing granzyme B were significantly elevated in the pHT group compared to healthy controls suggesting increased MAIT cell activity in the pHT cord blood. Similarly, in the MAP group, the absolute number of total CD3+ TCRVα7.2+ CD161high cells, but not individual CD4+ or negative subsets, were significantly increased compared with healthy controls' cord blood. Absolute numbers of total CD3+ TCRVα7.2+ CD161high cells and their subsets were comparable in the cord blood of the GD group compared with healthy controls. Finally, the absolute number of total ILCs and ILC3 subset were significantly elevated in only pHT cord blood compared with healthy controls. Our data also reveal that IFN-γ+ or granzyme B+ cell numbers negatively correlated with fetal birth weight. CONCLUSIONS: CD3+ TCRVα7.2+ CD161high cells and ILCs show unique expansion and activity in the cord blood of pregnant women with distinct diseases causing IUGR and may play roles in fetal growth restriction.

Chemokines in Gestational Diabetes Mellitus.

Background: Studies investigating chemokines in gestational diabetes mellitus (GDM) have yielded mixed results. The purpose of this meta-analysis was to explore whether concentrations of chemokines in patients with GDM differed from that of the controls. Methods: Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we systematically searched Web of Science, Embase, Cochrane Library, and PubMed databases for articles, published in any language, on chemokines and GDM through August 1st, 2021. The difference in concentrations of chemokines between patients with GDM and controls was determined by a standardized mean difference (SMD) with a 95% confidence interval (CI), calculated in the meta-analysis of the eligible studies using a random-effects model with restricted maximum-likelihood estimator. Results: Seventeen studies met the inclusion criteria for the meta-analysis. Altogether, they included nine different chemokines comparisons involving 5,158 participants (1,934 GDM patients and 3,224 controls). Results showed a significant increase of these chemokines (CCL2, CXCL1, CXCL8, CXCL9, and CXCL12) in the GDM patients compared with the controls. However, there was a significant decrease of the chemokines, CCL4, CCL11 and CXCL10, in the GDM patients compared with the controls. Moreover, subgroup analysis revealed a potential role of chemokines as biomarkers in relation to laboratory detection (different sample type and assay methods) and clinical characteristics of GDM patients (ethnicity and body mass index). Conclusion: GDM is associated with several chemokines (CCL2, CCL4, CCL11, CXCL1, CXCL8, CXCL9, CXCL10 and CXCL12). Therefore, consideration of these chemokines as potential targets or biomarkers in the pathophysiology of GDM development is necessary. Notably, the information of subgroup analysis underscores the importance of exploring putative mechanisms underlying this association, in order to develop new individualized clinical and therapeutic strategies.

Study on the Effects of Individualized Nutritional Intervention on Pregnancy Outcome and Neonatal Immune Function in Patients with Gestational Diabetes Mellitus.

OBJECTIVE: To study the effects of individualized nutritional intervention on pregnancy outcome and neonatal immune function in patients with gestational diabetes mellitus (GDM). METHODS: A retrospective analysis was conducted on 100 GDM patients from the obstetrics and gynecology department of our institute between February 2019 and February 2020. The patients were allocated into the control group given regular intervention and the experimental group given individualized nutritional intervention according to different intervention measures, with 50 cases in each group. The comparison was carried out for patients in the two groups with regard to their modality of delivery, neonatal health, their plasma glucose in fasting state, 2 h after eating, and before bedtime; glycohemoglobin at 8 months of pregnancy, at 9 months of pregnancy, during labor, and 1 month after delivery; their complications; and neonatal CD3+, CD4+, and CD8+ levels. RESULTS: The experimental group outperformed the control group in terms of the spontaneous delivery rate, the number of healthy neonates, and neonatal CD3+, CD4+, and CD8+ levels (P < 0.05). The plasma glucose in fasting state, 2 h after eating, and before bedtime; the glycohemoglobin at 8 months of pregnancy, at 9 months of pregnancy, during labor, and 1 month after delivery; and the incidence of complications of the experimental group were significantly lower than those of the control group (P < 0.05). CONCLUSION: Individualized nutritional intervention increases the rate of spontaneous delivery in GDM patients, enhances neonatal immune function, stabilizes plasma glucose, and reduces complications.

Outcomes of pregnancy in autoimmune hepatitis: A population-based study.

BACKGROUND AND AIMS: Autoimmune hepatitis (AIH) disproportionately affects young women, which may have implications in pregnancy. However, data on pregnancy outcomes in women with AIH are limited. APPROACH AND RESULTS: Using weighted discharge data from the United States National Inpatient Sample from 2012 to 2016, we evaluated pregnancies after 20 weeks gestation and compared outcomes in AIH to other chronic liver diseases (CLD) or no CLD in pregnancy. The association of AIH with maternal and perinatal outcomes was assessed by logistic regression. Among 18,595,345 pregnancies, 935 (<0.001%) had AIH (60 with cirrhosis) and 120,100 (0.006%) had other CLD (845 with cirrhosis). Temporal trends in pregnancies with AIH remained stable from 2008 to 2016 with 1.4-6.8/100,000 pregnancies per year (p = 0.25). On adjusted analysis, the odds of gestational diabetes (GDM) and hypertensive complications (pre-eclampsia, eclampsia, or hemolysis, elevated liver enzymes, low platelets) were significantly higher in AIH compared to other CLD (GDM: OR 2.2, 95% CI: 1.5-3.9, p < 0.001; hypertensive complications: OR: 1.8, 95% CI: 1.0-3.2, p = 0.05) and also compared to no CLD in pregnancy (GDM: OR: 2.4, 95% CI: 1.6-3.6, p < 0.001; hypertensive complications: OR: 2.4, 95% CI: 1.3-4.1, p = 0.003). AIH was also associated with preterm births when compared with women without CLD (OR: 2.0, 95% CI: 1.2-3.5, p = 0.01). AIH was not associated with postpartum hemorrhage, maternal, or perinatal death. CONCLUSIONS: Rates of pregnancy in women with AIH have remained stable in recent years, although AIH is associated with notable maternal and perinatal risks, such as GDM, hypertensive complications, and preterm birth. Whether these risks are influenced by steroid use and/or AIH disease activity warrants evaluation. These data support a low risk of postpartum hemorrhage and favorable survival of mothers and infants.

Omentin-1 and its relationship with inflammatory factors in maternal plasma and visceral adipose tissue of women with gestational diabetes mellitus.

PURPOSE: To investigate the association of omentin-1 and inflammatory factors in serum and visceral adipose tissue (VAT) of women with gestational diabetes mellitus (GDM) compared to normal pregnant (NP) subjects. Furthermore, to examine their correlation with maternal clinical characteristics. METHODS: We compared 116 GDM women to 115 NP women, at the time of cesarean section. Circulating omentin-1 and pro-inflammatory (IL-1ß, IL-6, TNF-α), and anti-inflammatory cytokines (IL-1RA, IL-10) were examined. Moreover, their mRNA expression in VAT, along with inflammatory factors involved in the NF-κB pathway (TLR2, TLR4, NF-κB, IKκB), were examined. RESULTS: Circulating omentin-1 (p = 0.022) was lower and circulating IL-1-ß, IL-1RA, as well as IL-10 (p = 0.005, p = 0.007, and p = 0.015, respectively), were higher in GDM compared to NP women. Omentin-1 correlated negatively with pre-pregnancy and gestational BMI, and HOMA-IR in all women, but was not associated with cytokines. TLR2, TLR4, IL-1ß, IL-1RA, IL-6, IL-10 mRNA expression in VAT was lower in GDM compared with controls (p < 0.05 all). In multivariate analysis, BMI at delivery was significantly correlated to omentin-1 concentrations in all and NP subjects. In addition, omentin-1 expression was correlated to inflammatory gene expression in all, GDM and NP, women (p < 0.05 all). CONCLUSION: Serum levels and VAT gene expression of omentin-1 are not independently linked to GDM; notwithstanding, GDM women have a VAT-altered inflammatory status. In addition, no systemic association between omentin-1 and inflammatory factors was found, whereas associations between their expression in all women were observed, indicating that expression of these adipokines is linked between them regardless of GDM.

Insulin Increases Adipose Adiponectin in Pregnancy by Inhibiting Ubiquitination and Degradation: Impact of Obesity.

CONTEXT: Circulating adiponectin levels are decreased in pregnant women with obesity or gestational diabetes, and this is believed to contribute to the insulin resistance and increased risk of fetal overgrowth associated with these conditions. However, the molecular mechanisms regulating adiponectin secretion from maternal adipose tissues in pregnancy are poorly understood. OBJECTIVE: We tested the hypothesis that obesity in pregnancy is associated with adipose tissue insulin resistance and increased adiponectin ubiquitination and degradation, caused by inflammation and endoplasmic reticulum (ER) stress. METHODS: Visceral adipose tissues were collected from lean and obese pregnant humans and mice. Total and ubiquitinated adiponectin, and markers of inflammation, ER stress, and insulin resistance were examined in adipose tissues. The role of insulin, inflammation, and ER stress in mediating adiponectin ubiquitination and degradation was examined using 3T3L-1 adipocytes. RESULTS: Obesity in pregnancy is associated with adipose tissue inflammation, ER stress, insulin resistance, increased adiponectin ubiquitination, and decreased total abundance of adiponectin. Adiponectin ubiquitination was increased in visceral fat of obese pregnant women as compared to lean pregnant women. We further observed that insulin prevents, whereas ER stress and inflammation promote, adiponectin ubiquitination and degradation in differentiated 3T3-L1 adipocytes. CONCLUSION: We have identified adiponectin ubiquitination as a key mechanism by which obesity diminishes adiponectin secretion in pregnancy. This information will help us better understand the mechanisms controlling maternal insulin resistance and fetal growth in pregnancy and may provide a foundation for the development of strategies aimed at improving adiponectin production in pregnant women with obesity or gestational diabetes.

Decreased Monocyte Count Is Associated With Gestational Diabetes Mellitus Development, Macrosomia, and Inflammation.

CONTEXT: The immune system plays a central role in the pathophysiology of gestational diabetes mellitus (GDM). Monocytes, the main innate immune cells, are especially important in the maintenance of a normal pregnancy. OBJECTIVE: Here, we investigated the potential effect of monocytes in GDM. METHODS: Monocyte count was monitored throughout pregnancy in 214 women with GDM and 926 women without in a case-control and cohort study. Circulating levels of inflammatory cytokines, placenta-derived macrophages, and their products were measured. RESULTS: Throughout pregnancy, monocyte count was significantly decreased in women with GDM, and was closely associated with glucose level, insulin resistance, and newborn weight. First-trimester monocyte count outperformed that of the second and third trimester as a risk factor and diagnostic predictor of GDM and macrosomia both in the case-control and cohort study. In addition, our cohort study showed that as first-trimester monocyte count decreased, GDM and macrosomia incidence, glucose level, and newborn weight increased in a stepwise manner. Risk of GDM started to decrease rapidly when first-trimester monocyte count exceeded 0.48 × 109/L. Notably, CD206 and interleukin 10 (IL-10) were significantly lower, whereas CD80, CD86, tumor necrosis factor α (TNF-α), and interleukin 6 (IL-6) were higher both in GDM placental tissue and peripheral blood. First-trimester monocyte count was positively related to IL-10 and CD206, but negatively related to CD80, CD86, TNF-α, and IL-6. CONCLUSION: Decreased monocyte count throughout pregnancy was closely associated with the development of GDM, macrosomia, and the chronic inflammatory state of GDM. First-trimester monocyte count has great potential as an early diagnostic marker of GDM.

Phoenixin-20 ameliorates gestational diabetes mellitus (GDM) symptoms and placental insults in an experimental mouse model.

BACKGROUND AND PURPOSE: Gestational diabetes mellitus (GDM) is a complication commonly observed in pregnancy, closely associated with increased oxidative stress, inflammatory response, and endoplasmic reticulum (ER) stress. Phoenixin-20 (PNX-20) is a newly reproductive hormone from the hypothalamus that has displayed pleiotropic effects. The promising inhibitory effects of PNX-20 on inflammation have recently been widely reported. The present study aims to investigate the protective effect of PNX-20 on GDM induced placental insults. METHODS: A GDM model was established on C57BLKsJ db/+ mice. The expression level of GPR173 was evaluated using RT-PCR and western blotting analysis. The serum level of glucose, insulin, lipid profiles, and oxidative stress indicators were detected with commercial kits. Fetal analysis was performed to evaluate the reproductive ability. ELISA was used to detect the production of inflammatory factors. The expressions of p-eIF-2α, ATF4, and GRP78 were evaluated with western blotting assay. RESULTS: Firstly, we found that GPR173 is expressed in the placenta tissue. Secondly, the elevated blood glucose level and lipid level, declined serum insulin level, fetus alive ratio, fetal and placenta weight, and shorten crown-rump length, were observed in the placenta tissue of GDM mice, which were reversed by treatment with PNX-20. Thirdly, the excessively released inflammatory factors and activated oxidative stress in GDM mice were alleviated by the administration of PNX-20. Lastly, the activated eIF-2α/ATF4 ER stress signaling pathway in GDM mice was dramatically suppressed by PNX-20. CONCLUSION: Our data revealed a protective property of PNX-20 against placental insults resulted from GDM.

Immunoendocrine Dysregulation during Gestational Diabetes Mellitus: The Central Role of the Placenta.

Gestational Diabetes Mellitus (GDM) is a transitory metabolic condition caused by dysregulation triggered by intolerance to carbohydrates, dysfunction of beta-pancreatic and endothelial cells, and insulin resistance during pregnancy. However, this disease includes not only changes related to metabolic distress but also placental immunoendocrine adaptations, resulting in harmful effects to the mother and fetus. In this review, we focus on the placenta as an immuno-endocrine organ that can recognize and respond to the hyperglycemic environment. It synthesizes diverse chemicals that play a role in inflammation, innate defense, endocrine response, oxidative stress, and angiogenesis, all associated with different perinatal outcomes.

Protocatechuic acid influences immune-metabolic changes in the adipose tissue of pregnant women with gestational diabetes mellitus.

Gestational diabetes mellitus (GDM) is associated with immune metabolic changes that increase women's risk of developing metabolic disorders later in life. Nutritional intervention is a crucial component in reducing the burden of these pathological features. We examined whether protocatechuic acid (PCA), a major metabolite of anthocyanins abundant in plant food, is able to exert insulin-mimetic activity and modulate inflammation in the visceral adipose tissue (VAT) obtained at delivery, from pregnant women with GDM or normal glucose tolerance (NGT). PCA stimulated glucose uptake in the VAT from both GDM and NGT women. This capability was associated with increased phosphorylation of p38 mitogen-activated protein kinase (p38MAPK), as further demonstrated by the inhibitory effect of SB203580, a p38MAPK inhibitor, on PCA-induced glucose uptake. The GDM-VAT expressed lower adiponectin levels and PCA stimulated adiponectin release in the NGT-VAT and, albeit to a lower extent, in the GDM-VAT. Higher levels of IL6 and TNFα were secreted by the GDM-VAT compared with the NGT one, and PCA had no effects on them. PCA reduced the overexpression of vasoactive intestinal peptide receptor 2 (VPAC2) in the GDM-VAT. Further studies are needed to establish whether and how anthocyanins and food rich in these compounds may contribute to prevent or delay metabolic disorders in women with GDM.

Distribution of complete blood count constituents in gestational diabetes mellitus.

BACKGROUND TRIAL DESIGN: The incidence rate of gestational diabetes is high. In the long run, it harms the health of both the mother and child. In order to understand the distribution of hematological cells with gestational diabetes mellitus (GDM), a longitudinal cohort study was conducted from 2012 to 2018. METHODS: A longitudinal case control study of 1860 pregnant women was conducted between 2012 and 2018. Data of hematological parameters at 11 time points of gestational stage were obtained from a laboratory database. Repeated measures analysis and independent t-test were used to analyze the effect of the hematological parameters on GDM. RESULTS: The trend of blood cells fluctuated with gestational age in normal controls but was more remarkable in GDM. Compared with the controls, blood neutrophils, lymphocytes, and monocytes augmented in the second trimester but decreased in the third trimester; platelet (PLT) and thrombocytocrit increased throughout the three trimesters, and red blood cell (RBC) was abundant in the last 2 trimesters in GDM. CONCLUSIONS: Peripheral blood leukocytes, platelets, and erythrocytes were significantly different during gestation between GDM and normal controls. Inflammation may also be involved in GMD.

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

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

Association of Complement-Related Proteins in Subjects With and Without Second Trimester Gestational Diabetes.

Introduction: Gestational Diabetes Mellitus (GDM) development is related to underlying metabolic syndrome that is associated with elevated complement C3 and C4. Elevated C3 levels have been associated with preeclampsia and the development of macrosomia. Methods: This case-control study included 34 pregnant women with GDM and 16 non-diabetic (ND) women in their second trimester. Complement-related proteins were measured and correlated with demographic, biochemical, and pregnancy outcome data. Results: GDM women were older with a higher BMI (p<0.001); complement C3, C4 and Factor-H were significantly elevated (p=0.001, p=0.05, p=0.01, respectively). When adjusted for age and BMI, Complement C3 (p=0.04) and Factor-H (p=0.04) remained significant. Partial correlation showed significant correlation between C4 with serum alanine aminotransferase (ALT) (p<0.05) and 2nd term diastolic blood pressure (p<0.05); Factor-H and C-reactive protein (CRP; p<0.05). Pearson bivariate analysis revealed significant correlations between C3, C4, and Factor-H and CRP; p<0.05; C3 and gestational age at delivery (GA; p<0.05); C4 and ALT and second-trimester systolic blood pressure (STBP) (p=0.008 and p<0.05, respectively); Factor-H and glycated hemoglobin (HbA1c) (p<0.05). Regression analysis showed that the elevation of C3 could be accounted for by age, BMI, GA and CRP, with CRP being the most important predictor (p=0.02). C4 elevation could be accounted for by ALT, CRP and STBP. CRP predicted Factor-H elevation. Conclusion: The increased C3, C4 and Factor-H during the second trimester of pregnancy in GDM are not independently associated with GDM; inflammation and high BMI may be responsible for their elevation. The elevation of second trimester C3 in GDM is associated with earlier delivery and further work is needed to determine if this is predictive.

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.

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

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