Evaluation of Circulating Determinants of Beta-Cell Function in Women With and Without Gestational Diabetes

Pathophysiology from preconception, during pregnancy, and beyond

Gestational diabetes is the most common medical complication in pregnancy. Historically, gestational diabetes was considered a pregnancy complication involving treatment of rising glycaemia late in the second trimester. However, recent evidence challenges this view. Pre-pregnancy and pregnancy-specific factors influence gestational glycaemia, with open questions regarding roles of non-glycaemic factors in the aetiology and consequences of gestational diabetes. Varying patterns of insulin secretion and resistance in early and late pregnancy underlie a heterogeneity of gestational diabetes in the timing and pathophysiological subtypes with clinical implications: early gestational diabetes and insulin resistant gestational diabetes subtypes are associated with a higher risk of pregnancy complications. Metabolic perturbations of early gestational diabetes can affect early placental development, affecting maternal metabolism and fetal development. Fetal hyperinsulinaemia can affect the development of multiple fetal tissues, with short-term and long-term consequences. Pregnancy complications are prevented by managing glycaemia in early and late pregnancy in some, but not all women with gestational diabetes. A better understanding of the pathophysiology and heterogeneity of gestational diabetes will help to develop novel management approaches with focus on improved prevention of maternal and offspring short-term and long-term complications, from pre-conception, throughout pregnancy, and beyond.

Symptoms of Posttraumatic Stress Disorder are Associated with Altered Glucose Parameters in Early and Late Gestation

OBJECTIVE

Posttraumatic stress disorder (PTSD) is associated with increased risk for insulin resistance and the development of diabetes outside of pregnancy. In pregnancy, emerging evidence suggests that PTSD is associated with increased risk for gestational diabetes; however, it is not yet known how PTSD is associated with disruptions in glucose processing across gestation. Therefore, the aim of the current study was to test associations between PTSD symptoms and glucose parameters in early and late gestation among pregnant people without a history of pregestational diabetes.

STUDY DESIGN

Two 34 participants were included in these analyses. PTSD symptoms were measured using the PTSD Checklist for DSM-5 (PCL-5) in early gestation. Fasting blood samples were collected at approximately 12 and 32 gestational weeks and were used to calculate β-cell function and insulin sensitivity.

RESULTS

Participants were 31 years old (standard deviation [SD] = 6) with body mass index (BMI) of 36 kg/m2 (SD = 7) at enrollment, 26% reported their ethnicity as Hispanic, 62% reported their race as White, 17% Black, 2% Asian, 3% Native American, 9% more than one race, and 11% unknown/not reported. Hierarchical linear regression analyses revealed that, after adjusting for several covariates including maternal age, race, ethnicity, BMI, apnea hypopnea index, and depressive symptoms, PTSD symptoms were positively associated with β-cell function in early (β = 0.230, p = 0.016) and late gestation (β = 0.238, p = 0.037).

CONCLUSION

Higher PTSD symptoms were associated with greater insulin secretion over pregnancy in this sample. More research is needed to replicate these findings and evaluate the effects of treatment of PTSD on mitigating the risk for gestational diabetes.

KEY POINTS

· We examined associations among symptoms of PTSD and glucose parameters over pregnancy.. · Symptoms of PTSD were positively associated with β-cell function over pregnancy.. · Symptoms of PTSD were not associated with insulin resistance over pregnancy..

Insulin Sensitivity, Islet Cell Function, and Incretin Axis in Pregnant Women With and Without Gestational Diabetes Mellitus

Introduction

The aim of this study was to compare insulin sensitivity, islet cell function, and incretin axes in pregnant subjects with GDM and normal healthy controls.

Methods

Pregnant women at 24 to 28 weeks of gestation were subjected to a 75 g oral glucose tolerance test (OGTT). Samples for glucose, insulin, glucagon, glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) were collected at 0, 30, 60, and 120 min during the OGTT. The Matsuda index (MI) and insulin secretion and sensitivity index-2 (ISSI-2) were assessed. The glucagon suppression index (GSI) was calculated along with the area under the curve (AUC) for glucose, insulin, glucagon, GLP-1, and GIP.

Results

A total of 48 pregnant women (25 GDM and 23 controls) were finally analysed. The MI and ISSI-2 were low in the GDM group [4.31 vs. 5.42; P = 0.04], [1.99 vs. 3.18, P ≤ 0.01] respectively). Total AUCglucagon was higher in the GDM group (7411.7 vs. 6320.1, P = 0.02). GSI30 was significantly lower in the GDM group (-62.6 vs. -24.7, P = 0.03). Fasting GLP-1 levels were low in GDM women (17.3 vs. 22.2, P = 0.04). The total AUCGLP-1 positively correlated with total GSI in the GDM group.

Conclusion

Asian-Indian GDM women have high insulin insensitivity, islet cell dysfunction, and low fasting GLP-1. Incretin axis dysfunction plays a potential role in their islet cell dysfunction.

Patients with gestational diabetes mellitus may be treated in both early and late pregnancy, especially in patients with pre-pregnancy overweight: A cross-sectional study in Japan

The significance of diagnosing gestational diabetes mellitus (GDM) in early pregnancy is controversial. We used the International Association of Diabetes and Pregnancy Study Group (IADPSG) criteria to investigate whether clinical background and neonatal outcomes differ depending on when GDM is diagnosed in early or late pregnancy. This was a single-center, observational study conducted between November 2012 and March 2020 at St. Marianna University Hospital (Kawasaki, Japan). We compared the background and perinatal outcomes of patients with GDM depending on the time of diagnosis (at < 24 gestational weeks or ≥ 24 weeks). Insulin sensitivity index, homeostasis model assessment of insulin resistance, and β-cell function were calculated from a 75-g oral glucose tolerance test. Stratified analysis was performed by pre-pregnancy BMI in patients with early GDM. As a result, in the 507 patients, 89.9% gave birth at our hospital. The pre-pregnancy BMI was significantly higher in patients with early GDM than in those with late GDM (the median [interquartile range], 22.7 [20.3, 26.3] and 21.5 [19.3, 23.8] kg/m2, respectively; p = 0.001). Perinatal outcomes were not different between the two groups. However, in the subgroup analysis of patients with early GDM, the prevalence of large-for-gestational-age infants was significantly higher in the group with overweight (15.4% vs 2.1%, respectively; p = 0.008). In conclusion, patients with GDM using the IADPSG criteria in early pregnancy may be treated, especially in patients with pre-pregnancy overweight.

Obesity and gestational diabetes independently and collectively induce specific effects on placental structure, inflammation and endocrine function in a cohort of South African women

Maternal obesity and gestational diabetes mellitus (GDM) are associated with insulin resistance and health risks for mother and offspring. Obesity is also characterized by low-grade inflammation, which in turn, impacts insulin sensitivity. The placenta secretes inflammatory cytokines and hormones that influence maternal glucose and insulin handling. However, little is known about the effect of maternal obesity, GDM and their interaction, on placental morphology, hormones and inflammatory cytokines. In a South African cohort of non-obese and obese pregnant women with and without GDM, this study examined placental morphology using stereology, placental hormone and cytokine expression using real-time PCR, western blotting and immunohistochemistry, and circulating TNFα and IL-6 concentrations using ELISA. Placental expression of endocrine and growth factor genes was not altered by obesity or GDM. However, LEPTIN gene expression was diminished, syncytiotrophoblast TNFα immunostaining elevated and stromal and fetal vessel IL-6 staining reduced in the placenta of obese women in a manner that was partly influenced by GDM status. Placental TNFα protein abundance and maternal circulating TNFα concentrations were reduced in GDM. Both maternal obesity and, to a lesser extent, GDM were accompanied by specific changes in placental morphometry. Maternal blood pressure and weight gain and infant ponderal index were also modified by obesity and/or GDM. Thus, obesity and GDM have specific impacts on placental morphology and endocrine and inflammatory states that may relate to pregnancy outcomes. These findings may contribute to developing placenta-targeted treatments that improve mother and offspring outcomes, which is particularly relevant given increasing rates of obesity and GDM worldwide. KEY POINTS: Rates of maternal obesity and gestational diabetes (GDM) are increasing worldwide, including in low-middle income countries (LMIC). Despite this, much of the work in the field is conducted in higher-income countries. In a well-characterised cohort of South African women, this study shows that obesity and GDM have specific impacts on placental structure, hormone production and inflammatory profile. Moreover, such placental changes were associated with pregnancy and neonatal outcomes in women who were obese and/or with GDM. The identification of specific changes in the placenta may help in the design of diagnostic and therapeutic approaches to improve pregnancy and neonatal outcomes with particular significant benefit in LMICs.

Human Placental Lactogen in Relation to Maternal Metabolic Health and Fetal Outcomes: A Systematic Review and Meta-Analysis

Human placental lactogen (hPL) is a placental hormone which appears to have key metabolic functions in pregnancy. Preclinical studies have putatively linked hPL to maternal and fetal outcomes, yet-despite human observational data spanning several decades-evidence on the role and importance of this hormone remains disparate and conflicting. We aimed to explore (via systematic review and meta-analysis) the relationship between hPL levels, maternal pre-existing and gestational metabolic conditions, and fetal growth. MEDLINE via OVID, CINAHL plus, and Embase were searched from inception through 9 May 2022. Eligible studies included women who were pregnant or up to 12 months post-partum, and reported at least one endogenous maternal serum hPL level during pregnancy in relation to pre-specified metabolic outcomes. Two independent reviewers extracted data. Meta-analysis was conducted where possible; for other outcomes narrative synthesis was performed. 35 studies met eligibility criteria. No relationship was noted between hPL and gestational diabetes status. In type 1 diabetes mellitus, hPL levels appeared lower in early pregnancy (possibly reflecting delayed placental development) and higher in late pregnancy (possibly reflecting increased placental mass). Limited data were found in other pre-existing metabolic conditions. Levels of hPL appear to be positively related to placental mass and infant birthweight in pregnancies affected by maternal diabetes. The relationship between hPL, a purported pregnancy metabolic hormone, and maternal metabolism in human pregnancy is complex and remains unclear. This antenatal biomarker may offer value, but future studies in well-defined contemporary populations are required.

The effects of prenatal dietary supplements on blood glucose and lipid metabolism in gestational diabetes mellitus patients: A systematic review and network meta-analysis protocol of randomized controlled trials

BACKGROUND

Several randomized controlled trials (RCT) investigated antenatal dietary supplements' effect on gestational diabetes mellitus patients' fasting plasma glucose levels, glycated hemoglobin levels, homeostasis model assessment of- insulin resistance and β-cell function, quantitative insulin sensitivity check index for glucose, high-, low-, and very-low-density lipoprotein cholesterol levels, total cholesterol levels, triglyceride levels, and triglyceride to high-density lipoprotein ratio. However, an efficacy comparison across various dietary supplements and their co-supplements are unavailable for these outcomes. Therefore, a systematic review protocol is proposed here to make a network meta-analysis (NMA)-based juxtaposition across the following dietary supplements- vitamins, Myo-inositol, choline, minerals, probiotics, prebiotics, synbiotics, and omega-3 fatty acids.

MATERIALS AND METHODS

A database search will ensue in the PubMed, Embase, and Scopus databases for RCTs testing the above, irrespective of their geographical origin. Data on population characteristics, compared interventions, and outcomes of interest will get abstracted from the studies included in the proposed review. Each of the reviewed studies will get appraised using the revised Cochrane tool. For each outcome, the comparative efficacy across interventions will be estimated in weighted or standardized mean difference using the frequentist method NMA and presented with their 95% confidence interval using league tables. By constructing network maps and comparison-adjusted funnel plots, a visual assessment of the inter-interventional relation and publication bias in each NMA model will happen, respectively. The best-ranked intervention prediction for respective outcomes will transpire using the surface under the cumulative ranking curve values. The Stata statistical software (version 16) will be used for analysis, and statistical significance will be determined at p<0.05 and 95% confidence interval.

TRIAL REGISTRATION

PROSPERO registration number: CRD42020214378.

Novel Biomolecules in the Pathogenesis of Gestational Diabetes Mellitus 2.0

Gestational diabetes mellitus (GDM) has become a major public health problem and one of the most discussed issues in modern obstetrics. GDM is associated with serious adverse perinatal outcomes and long-term health consequences for both the mother and child. Currently, the importance and purposefulness of finding a biopredictor that will enable the identification of women with an increased risk of developing GDM as early as the beginning of pregnancy are highly emphasized. Both “older” molecules, such as adiponectin and leptin, and “newer” adipokines, including fatty acid-binding protein 4 (FABP4), have proven to be of pathophysiological importance in GDM. Therefore, in our previous review, we presented 13 novel biomolecules, i.e., galectins, growth differentiation factor-15, chemerin, omentin-1, osteocalcin, resistin, visfatin, vaspin, irisin, apelin, FABP4, fibroblast growth factor 21, and lipocalin-2. The purpose of this review is to present the potential and importance of another nine lesser known molecules in the pathogenesis of GDM, i.e., 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid (CMPF), angiopoietin-like protein-8 (ANGPTL-8), nesfatin-1, afamin, adropin, fetuin-A, zonulin, secreted frizzled-related proteins (SFRPs), and amylin. It seems that two of them, fetuin-A and zonulin in high serum levels, may be applied as biopredictors of GDM.

Association between sleep disordered breathing in early pregnancy and glucose metabolism

STUDY OBJECTIVES

To examine the association between maternal sleep disordered breathing (SDB) and glucose metabolism in early gestation.

METHODS

Women with body mass index (BMI) ≥27 kg/m2 and singleton pregnancies underwent in-home sleep study (HSAT) and homeostatic model assessment (HOMA) in early pregnancy. Insulin resistance (HOMA-IR) and β-cell function (HOMA %B) were derived. Exclusion criteria included pregestational diabetes, use of continuous positive airway pressure and chronic steroid therapy. We performed linear regression analyses to evaluate the association between continuous measures of SDB (respiratory event index (REI), and oxygen desaturation index (ODI)) and glucose metabolism parameters (HOMA-IR and HOMA %B). Analyses were adjusted for a set of a priori selected variables which included gestational age, maternal age, BMI, ethnicity, race, and parity.

RESULTS

One hundred and ninety-two pregnant women with median (interquartile range) BMI of 35.14 (8.30) kg/m2 underwent HSAT and HOMA assessment at 11.14 (3) and 15.35 (4.14) gestational weeks, respectively. REI and ODI, as continuous values, were associated with HOMA-IR after adjusting for covariates. OSA (obstructive sleep apnea) diagnosis (REI > 5 events per hour) was not associated with HOMA-IR after adjusting for BMI (p ≥ 0.05). None of the parameters were associated with HOMA %B (p > 0.07).

CONCLUSIONS

SDB and insulin resistance are associated in early pregnancy, with a dose response association between respiratory event index severity and insulin resistance. Further studies are needed to establish if pregnant women with overweight and obesity may benefit from early SDB screening to improve glucose metabolic outcome. Clinical trials: NCT02412696, Positive Airway Pressure, Sleep Apnea, and the Placenta (PAP-SAP) https://clinicaltrials.gov/ct2/show/NCT02412696?term=Bourjeily&draw=2&rank=2 and NCT02917876, Predictors of De-novo Development of Obstructive Sleep Apnea in Pregnancy (Predictors) https://clinicaltrials.gov/ct2/show/NCT02917876?term=Bourjeily&draw=2&rank=1.

Lactogenic hormones in relation to maternal metabolic health in pregnancy and postpartum: protocol for a systematic review

INTRODUCTION

Maternal metabolic disease states (such as gestational and pregestational diabetes and maternal obesity) are reaching epidemic proportions worldwide and are associated with adverse maternal and fetal outcomes. Despite this, their aetiology remains incompletely understood. Lactogenic hormones, namely, human placental lactogen (hPL) and prolactin (PRL), play often overlooked roles in maternal metabolism and glucose homeostasis during pregnancy and (in the case of PRL) postpartum, and have clinical potential from a diagnostic and therapeutic perspective. This paper presents a protocol for a systematic review which will synthesise the available scientific evidence linking these two hormones to maternal and fetal metabolic conditions/outcomes.

METHODS AND ANALYSIS

MEDLINE (via OVID), CINAHL and Embase will be systematically searched for all original observational and interventional research articles, published prior to 8 July 2021, linking hPL and/or PRL levels (in pregnancy and/or up to 12 months postpartum) to key maternal metabolic conditions/outcomes (including pre-existing and gestational diabetes, markers of glucose/insulin metabolism, postpartum glucose status, weight change, obesity and polycystic ovary syndrome). Relevant fetal outcomes (birth weight and placental mass, macrosomia and growth restriction) will also be included. Two reviewers will assess articles for eligibility according to prespecified selection criteria, followed by full-text review, quality appraisal and data extraction. Where possible, meta-analysis will be performed; otherwise, a narrative synthesis of findings will be presented.

ETHICS AND DISSEMINATION

Formal ethical approval is not required as no primary data will be collected. The results will be published in a peer-reviewed journal and presented at conference meetings, and will be used to inform future research directions.

PROSPERO REGISTRATION NUMBER

CRD42021262771.

Rate of Gestational Weight Gain and Glucose-Insulin Metabolism Among Hispanic Pregnant Women With Overweight and Obesity

CONTEXT

Hispanic women are at elevated risk of gestational glucose intolerance and postpartum type 2 diabetes compared with non-Hispanic White women. Identification of potentially modifiable factors contributing to this trajectory of beta-cell dysfunction is warranted.

OBJECTIVE

We aimed to determine the association between rate of gestational weight gain (rGWG) and glucose-insulin metabolism in Hispanic pregnant women with overweight and obesity.

METHODS

This cross-sectional, observational study, conducted from 2018-2020 at the clinical research center at University of California, Irvine, included 33 nondiabetic Hispanic pregnant women at 28 to 30 weeks' gestation with pre-pregnancy body mass index (BMI) 25.0 to 34.9 kg/m2. Participants consumed a standardized liquid mixed meal after an overnight fast. Serial blood samples were collected at fasting and up to 2 hours postprandial. The glucose and insulin area under the curve (AUC), insulin sensitivity index (ISI) and insulin secretion sensitivity index (ISSI)-2 were computed.

RESULTS

Average rGWG (0.36 ± 0.22 kg/week) was classified as excessive in 60% of women. While rGWG was not associated with the glucose or insulin AUC or ISI, it accounted for 13.4% of the variance in ISSI-2 after controlling for covariates (maternal age, parity, and pre-pregnancy BMI); for each 1 unit increase in rGWG, ISSI-2 decreased 2.1 units (P = 0.015).

CONCLUSION

Even in the absence of gestational diabetes, rGWG was inversely associated with beta-cell function in a high-risk population of Hispanic pregnant women with overweight and obesity. Beta-cell decline is an established risk factor for transition to type 2 diabetes, and these cross-sectional findings highlight rGWG as a potentially modifiable contributor to this process.

Adiposity, related biomarkers, and type 2 diabetes after gestational diabetes: The Diabetes Prevention Program

OBJECTIVE

This study investigated associations of adiposity and adiposity-related biomarkers with incident type 2 diabetes (T2D) among parous women.

METHODS

Among women in the Diabetes Prevention Program (DPP) who reported a previous live birth, circulating biomarkers (leptin, adiponectin, sex hormone-binding globulin, and alanine aminotransferase; n = 1,711) were measured at enrollment (average: 12 years post partum). Visceral (VAT) and subcutaneous adipose tissue areas at the L2-L3 region and the L3-L4 region were quantified by computed tomography (n = 477). Overall and stratified (by history of gestational diabetes mellitus [GDM]) adjusted Cox proportional hazards models were fit.

RESULTS

Alanine aminotransferase, L2-L3 VAT, and L3-L4 VAT were positively associated (hazard ratio [HR] for 1-SD increases: 1.073, p = 0.024; 1.251, p = 0.009; 1.272, p = 0.004, respectively), and adiponectin concentration was inversely associated with T2D (HR 0.762, p < 0.001). Whereas leptin concentration was not associated with T2D overall, in GDM-stratified models, a 1-SD higher leptin was positively associated with risk of T2D in women without GDM (HR: 1.126, p = 0.016) and inversely in women with a history of GDM (HR: 0.776, p = 0.013, interaction p = 0.002).

CONCLUSIONS

Among parous women, alanine aminotransferase and VAT are positively associated with incident T2D, whereas adiponectin is inversely associated. Leptin is associated with higher risk of T2D in women with a history of GDM but a lower risk in women without a history of GDM.

Prolactin in relation to gestational diabetes and metabolic risk in pregnancy and postpartum: A systematic review and meta-analysis

CONTEXT

Pre-clinical evidence suggests that prolactin has important metabolic functions in pregnancy and postpartum, in addition to lactogenic actions.

OBJECTIVE

To explore the relationship between prolactin and maternal metabolic outcomes in human pregnancy and postpartum, particularly in relation to gestational diabetes mellitus (GDM).

DATA SOURCES

MEDLINE via OVID, CINAHL plus, Embase.

STUDY SELECTION

Eligible studies included women who were pregnant or up to 12 months postpartum, reporting at least one maternal serum prolactin level in relation to key metabolic outcomes including GDM, glycaemic parameters, obesity, and gestational weight gain.

DATA EXTRACTION

Two independent reviewers extracted data.

DATA SYNTHESIS

Twenty-six articles were included. Meta-analysis showed no relationship between maternal prolactin levels and GDM status, with a weighted mean difference of -2.14 ng/mL (95% CI -12.54 to 8.27 ng/mL, p=0.7) between GDM and controls in early pregnancy (n=3 studies) and -3.89 ng/mL (95% CI, -15.20 to 7.41 ng/mL, p=0.5) in late pregnancy (n=11 studies). In narrative synthesis of other outcomes (due to study heterogeneity and/or lack of data), prolactin levels were not associated with maternal glycaemic or weight-related parameters during pregnancy, but in the postpartum period (particularly with lactation) a high-prolactin environment was associated with low circulating insulin and beta-cell function, and increased insulin sensitivity.

CONCLUSIONS

Current evidence from human studies does not clearly support a relationship between prolactin and metabolic parameters during pregnancy, including with GDM status. Elevated prolactin was associated with lower insulin and beta-cell function and higher insulin sensitivity in the post-partum period, but the direction of causality remains unclear.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero/, identifier [CRD42021262771].

Placental Endocrine Activity: Adaptation and Disruption of Maternal Glucose Metabolism in Pregnancy and the Influence of Fetal Sex

The placenta is an endocrine fetal organ, which secretes a plethora of steroid- and proteo-hormones, metabolic proteins, growth factors, and cytokines in order to adapt maternal physiology to pregnancy. Central to the growth of the fetus is the supply with nutrients, foremost with glucose. Therefore, during pregnancy, maternal insulin resistance arises, which elevates maternal blood glucose levels, and consequently ensures an adequate glucose supply for the developing fetus. At the same time, maternal β-cell mass and function increase to compensate for the higher insulin demand. These adaptations are also regulated by the endocrine function of the placenta. Excessive insulin resistance or the inability to increase insulin production accordingly disrupts physiological modulation of pregnancy mediated glucose metabolism and may cause maternal gestational diabetes (GDM). A growing body of evidence suggests that this adaptation of maternal glucose metabolism differs between pregnancies carrying a girl vs. pregnancies carrying a boy. Moreover, the risk of developing GDM differs depending on the sex of the fetus. Sex differences in placenta derived hormones and bioactive proteins, which adapt and modulate maternal glucose metabolism, are likely to contribute to this sexual dimorphism. This review provides an overview on the adaptation and maladaptation of maternal glucose metabolism by placenta-derived factors, and highlights sex differences in this regulatory network.

Homocysteine level and gestational diabetes mellitus: a systematic review and meta-analysis

AIMS

It is reported that elevated homocysteine (Hcy) level represents an independent risk factor for gestational diabetes mellitus (GDM). However, the relationship between Hcy level and GDM remains controversial. Our study aimed to systematically review available literature linking Hcy to GDM for a comprehensive understanding of the relationship between circulating Hcy level and GDM in humans.

METHODS

PubMed, The Cochrane Library, and Web of Science were searched for studies published up to January 2021. Manual searches of references of the relevant studies were also conducted. Standard mean difference (SMD) with 95% confidence interval (95%CI) were calculated to evaluate the relationship between Hcy level and GDM using the Review Manager 5.3 and Stata 12.0.

RESULTS

Of 106 references reviewed, 12 studies with a total of 712 GDM patients contributed to the present meta-analysis. Hcy level was significantly elevated in women with GDM compared with those without GDM (SMD = 0.55; 95% CI: 0.25-0.85, p = .0003). In the subgroup meta-analyses, this evidence was more consistent among women with Hcy sampling during the second trimester (SMD = 0.76, 95% CI: 0.34-1.18, p = .0004) and with average age ≥30 years (SMD = 0.69, 95% CI: 0.25-1.12, p = .002).

CONCLUSION

The evidence indicated that the level of circulating Hcy was significantly elevated among women with GDM compared with those with normal glucose tolerance, especially with mean age ≥30 years and in the second trimester.

Visfatin level and gestational diabetes mellitus: a systematic review and meta-analysis

It is reported that elevated visfatin level is associated with gestational diabetes mellitus (GDM). However, the relationship between visfatin level and GDM remains controversial. The aim of our study was to systematically review available literature linking visfatin to GDM for a comprehensive understanding of the relationship between circulating visfatin level and GDM in human. PubMed, The Cochrane Library and Web of Science were searched for studies published up to July 2020. Standard mean difference with 95% confidence interval was calculated to evaluate the relationship between visfatin level and GDM using the Review Manager 5.3 and Stata 12.0. The evidence indicated that no significant difference was observed in the level of circulating visfatin between the women with GDM and normal glucose tolerance, suggesting circulating visfatin level is not independently related to GDM. Nevertheless, visfatin is involved in the development of GDM in obese women.

Effects of exogenous adiponectin supplementation in early pregnant PCOS mice on the metabolic syndrome of adult female offspring

Objective

PCOS is a heterogeneous endocrine disorder with both reproductive and metabolic abnormalities. At present, PCOS has been confirmed to have a certain genetic background. Compared with healthy women, the vast majority of PCOS patients have hyperandrogenemia, and this excessive androgen exposure during pregnancy may affect the development of female fetuses. The aim of the current study was to investigate the effect of adiponectin intervention during early pregnancy of obese mice with PCOS on the metabolic phenotype of adult female offspring.

Methods

After the PCOS model was established, C57BL/6J mice were divided into maternal-control, maternal-PCOS, and maternal-PCOS + APN groups. DHEA-induced PCOS mice were supplemented with adiponectin (10 mg/kg/day) in the early pregnancy in order to eliminate adverse hormone exposure and then traced for endocrine indicators in their adult female offspring, which were observed for metabolism syndrome or endocrine disturbance and exhibited the main effects of APN. To further explore the underlying mechanism, the relative expressions of phosphorylated AMPK, PI3K, and Akt were detected in the ovaries of offspring mice.

Results

The serum testosterone level of the maternal-PCOS + APN group in early pregnancy was significantly lower than that of the maternal-PCOS group (p < 0.01). The serum testosterone level in the offspring-PCOS + APN group was significantly lower than in the offspring-PCOS group (p <0.05), the diestrus time characterized by massive granulocyte aggregation in the estrus cycle was significantly shorter than in the offspring-PCOS group (p<0.05), and the phenotypes of PCOS-like reproductive disorders and metabolic disorders, such as obesity, insulin resistance, impaired glucose tolerance, and hyperlipidemia, were also significantly improved in the offspring-PCOS + APN group (p < 0.05). Compared with the control group, the expression levels of phosphorylated AMPK, PI3K, and Akt in the offspring-PCOS group were significantly decreased (p < 0.05), while those in the offspring-PCOS + APN group were significantly increased (p < 0.05).

Conclusions

APN intervention in early pregnancy significantly reduced the adverse effects of maternal obesity and high androgen levels during pregnancy on female offspring and corrected the PCOS-like endocrine phenotype and metabolic disorders of adult female offspring. This effect may be caused by the activation of the AMPK/PI3K-Akt signaling pathway in PCOS offspring mice.

Utility of in-hospital post-delivery fasting plasma glucose to predict postpartum glucose status in women with hyperglycaemia first detected in pregnancy: A prospective cohort study

Background

Women with hyperglycaemia first detected in pregnancy (HFDP), including those with gestational diabetes mellitus (GDM), should undergo a glucose evaluation 4–12 weeks after delivery. Globally, suboptimal postpartum return rates limit the opportunity to intervene in women with sustained hyperglycaemia and pragmatic solutions should be sought to bridge this gap.

Objective

To assess the utility of postpartum in-hospital glucose evaluation to predict the outcome of the oral glucose tolerance test (OGTT) performed 4–12 weeks after delivery.

Methods

The study was performed prospectively at Tygerberg Hospital, Cape Town, South Africa. Women with HFDP, classified as GDM based on the modified National Institute for Health and Care Excellence criteria, who delivered between November 2018 and June 2019 were included in the study. Fasting plasma glucose (FPG) was performed 24–72 hours after delivery (t1) in the postnatal ward, provided glucose lowering medication was discontinued at delivery. An OGTT 4–12 weeks postpartum (t2) was scheduled for the total cohort. We compared glucose values and glucose categories at t1 and t2 and evaluated antenatal characteristics of women who returned, compared to the group that was lost to follow-up.

Results

In-hospital post-delivery glucose assessment (t1) was performed in 115 women. Glucose levels were significantly lower at t1 compared to antenatal diagnostic values (t0) and assessment at t2. Of the fourteen women with hyperglycaemia at t2, none had abnormal fasting glucose concentrations at t1. Women with HFDP who fulfilled criteria for overt diabetes at t0, all (24/115) had normal fasting glucose levels at t1 except for IFG in one (1/24). The antenatal characteristics of women with HFDP who returned at t2, were similar to the women who did not return.

Conclusion

Based on this study, in-hospital fasting glucose 24–72 hours postpartum cannot replace the OGTT 4–12 weeks postpartum. Pragmatic solutions for low postpartum return rates in women with HFDP should be pursued.

Insulin secretory defect may be the major determinant of GDM in lean mothers

Aims

To compare the insulin sensitivity and secretion indices of pregnant Bangladeshi women with GDM and normal glucose tolerance (NGT).

Methods

This cross sectional study was performed with 40 GDM and equal number of NGT pregnant women diagnosed on basis of WHO criterion-2013 during 24–40 weeks of gestation. Glucose was measured by glucose oxidase method and fasting insulin by chemiluminescent immunoassay. Equations of homeostatic model assessment (HOMA) were used to calculate indices of insulin resistance (HOMA-IR), β-cell function (HOMA-B) and insulin sensitivity (HOMA-%S).

Results

The GDM group had significantly higher insulin resistance as indicated by higher fasting insulin value [GDM vs. NGT; 10.23 (7.94–14.50) vs. 7.07 (5.28–11.07) µIU/ml] and HOMA-IR [GDM vs. NGT; 2.47 (1.75–3.43) vs. 1.50 (0.99–2.22)] and poor β-cell secretion [GDM vs. NGT; HOMA-B: 113.37 (90.30–191.35) vs. 150.98 (109.85–271.72), median (IQR); p < 0.001 for all]. HOMA-B was significantly lower in GDM than NGT with BMI < 23 kg/m² [GDM vs. NGT; 63.37 (49.19–83.83) vs. 134.89 (93.50–193.17) ng/ml; p = 0.010] despite having statistically comparable difference in IR. BMI was found to be a significant predictor of HOMA-IR in GDM.

Conclusions

Though impairments of both insulin secretion and sensitivity are hallmarks in the pathogenesis of GDM, β-cell dysfunction contributes more to development of GDM in those with relatively lower BMI in our population.

Placental Lactogen as a Marker of Maternal Obesity, Diabetes, and Fetal Growth Abnormalities: Current Knowledge and Clinical Perspectives

Placental lactogen (PL) is a peptide hormone secreted throughout pregnancy by both animal and human specialized endocrine cells. PL plays an important role in the regulation of insulin secretion in pancreatic β-cells, stimulating their proliferation and promoting the expression of anti-apoptotic proteins. Cases of pregnancy affected by metabolic conditions, including obesity and diabetes, are related to alterations in the PL secretion pattern. Whereas obesity is most often associated with lower PL serum concentrations, diabetes results in increased PL blood levels. Disruptions in PL secretion are thought to be associated with an increased prevalence of gestational complications, such as placental dysfunction, diabetic retinopathy, and abnormalities in fetal growth. PL is believed to be positively correlated with birth weight. The impaired regulation of PL secretion could contribute to an increased incidence of both growth retardation and fetal macrosomia. Moreover, the dysregulation of PL production during the intrauterine period could affect the metabolic status in adulthood. PL concentration measurement could be useful in the prediction of fetal macrosomia in women with normal oral glucose tolerance test (OGTT) results or in evaluating the risk of fetal growth restriction, but its application in standard clinical practice seems to be limited in the era of ultrasonography.

Plasma Prolactin and Progesterone Levels and the Risk of Gestational Diabetes: A Prospective and Longitudinal Study in a Multiracial Cohort

Objective: Prolactin and progesterone are implicated in glucose homeostasis in and outside of pregnancy. However, their associations with gestational diabetes (GDM) risk were not well-understood. This study investigates this question in a prospective and longitudinal cohort. Methods: This is a nested case-control study of 107 incident GDM cases and 214 matched non-GDM controls within the NICHD Fetal Growth Studies-Singleton Cohort. Blood samples were collected at gestational weeks 10-14, 15-26, 23-31, and 33-39. The odds ratios (OR) of GDM were estimated using conditional logistic regression. The longitudinal changes in prolactin and progesterone were estimated using linear mixed-effects models. Results: Compared to controls, cases have significantly higher prolactin levels at weeks 10-14 (median: 50.4 vs. 42.1 ng/mL), and significantly lower progesterone levels at weeks 10-14 (median: 109.4 vs. 126.5 nmol/L). Prolactin levels at weeks 10-14 were significantly and positively associated with GDM risk; the adjusted ORs across increasing quartiles were 1.00, 1.13, 1.80, 2.33 (p-trend = 0.02). A similar but slightly attenuated association was observed at weeks 15-26 (p-trend = 0.05). Progesterone was not associated with GDM risk at either time points. Longitudinal changes in prolactin and progesterone between the first two visits were not associated with GDM risk. In addition, prolactin was significantly and positively associated with insulin and C-peptide levels at weeks 10-14, and significantly and inversely associated with C-peptide levels at weeks 15-26; progesterone was significantly and inversely associated with glucose and insulin levels. Conclusions: This study provided the first prospective evidence of a positive association between prolactin levels in early pregnancy and GDM risk.

Cord Blood Metabolomics: Association With Newborn Anthropometrics and C-Peptide Across Ancestries

CONTEXT

Newborn adiposity is associated with childhood obesity. Cord blood metabolomics is one approach that can be used to understand early-life contributors to adiposity and insulin resistance.

OBJECTIVE

To determine the association of cord blood metabolites with newborn adiposity and hyperinsulinemia in a multiethnic cohort of newborns.

DESIGN

Cross-sectional, observational study.

SETTING

Hyperglycemia and Adverse Pregnancy Outcome study.

PARTICIPANTS

One thousand six hundred multiethnic mother-newborn pairs.

MAIN OUTCOME MEASURE

Cord blood C-peptide, birthweight, and newborn sum of skinfolds.

RESULTS

Meta-analyses across four ancestry groups (Afro-Caribbean, Northern European, Thai, and Mexican American) demonstrated significant associations of cord blood metabolites with cord blood C-peptide, birthweight, and newborn sum of skinfolds. Several metabolites, including branched-chain amino acids (BCAAs), medium- and long-chain acylcarnitines, nonesterified fatty acids, and triglycerides were negatively associated with cord C-peptide but positively associated with birthweight and/or sum of skinfolds. 1,5-Anhydroglucitol, an inverse marker of recent maternal glycemia, was significantly inversely associated with birthweight and sum of skinfolds. Network analyses revealed groups of interrelated amino acid, acylcarnitine, and fatty acid metabolites associated with all three newborn outcomes.

CONCLUSIONS

Cord blood metabolites are associated with newborn size and cord blood C-peptide levels after adjustment for maternal body mass index and glucose during pregnancy. Negative associations of metabolites with C-peptide at birth were observed. 1,5-Anhydroglucitol appears to be a marker of adiposity in newborns. BCAAs were individually associated with birthweight and demonstrated possible associations with newborn adiposity in network analyses.

Maternal metabolites during pregnancy are associated with newborn outcomes and hyperinsulinaemia across ancestries

AIMS/HYPOTHESIS

We aimed to determine the association of maternal metabolites with newborn adiposity and hyperinsulinaemia in a multi-ethnic cohort of mother-newborn dyads.

METHODS

Targeted and non-targeted metabolomics assays were performed on fasting and 1 h serum samples from a total of 1600 mothers in four ancestry groups (Northern European, Afro-Caribbean, Mexican American and Thai) who participated in the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) study, underwent an OGTT at ~28 weeks gestation and whose newborns had anthropometric measurements at birth.

RESULTS

In this observational study, meta-analyses demonstrated significant associations of maternal fasting and 1 h metabolites with birthweight, cord C-peptide and/or sum of skinfolds across ancestry groups. In particular, maternal fasting triacylglycerols were associated with newborn sum of skinfolds. At 1 h, several amino acids, fatty acids and lipid metabolites were associated with one or more newborn outcomes. Network analyses revealed clusters of fasting acylcarnitines, amino acids, lipids and fatty acid metabolites associated with cord C-peptide and sum of skinfolds, with the addition of branched-chain and aromatic amino acids at 1 h.

CONCLUSIONS/INTERPRETATION

The maternal metabolome during pregnancy is associated with newborn outcomes. Maternal levels of amino acids, acylcarnitines, lipids and fatty acids and their metabolites during pregnancy relate to fetal growth, adiposity and cord C-peptide, independent of maternal BMI and blood glucose levels.

Upregulation Of Renal GLUT2 And SGLT2 Is Involved In High-Fat Diet-Induced Gestational Diabetes In Mice

INTRODUCTION

Gestational diabetes mellitus (GDM) is a metabolic disorder during mid- to late-pregnancy characterized by hyperglycemia, insulin resistance and fetal mal-development. Glucose transporter type 2 (GLUT2) and sodium-coupled glucose cotransporters 2 (SGLT2) in the proximal tubules play a critical role in the reabsorption of glucose and have been linked to the occurrence of type 2 diabetes mellitus (T2DM). Our study was designed to investigate the role of GLUT2 and SGLT2 in the pathogenesis of GDM, which is considered a forerunner of T2DM, and investigate the related molecular mechanism.

METHODS

High-fat diet (HFD) was utilized to build a GDM mouse model that closely induces metabolic abnormalities similar to human GDM. Body weight, blood glucose and serum insulin were recorded in the experimental process. Glucose tolerance was determined by the use of an intraperitoneal glucose tolerance test (IPGTT). In addition, levels of GLUT2 and SGLT2 were evaluated to further explore the underlying mechanism of GDM.

RESULTS

HFD feeding induced abnormal glucose metabolism as manifested by increased levels of blood glucose and insulin and prominent glucose intolerance. Additionally, fetal mice from mother feed on HFD showed higher mean body weight. Furthermore, HFD feeding led to an increase in the number of positive cells of GLUT2 and SGLT2 in the renal proximal tubule and the expressions of renal GLUT2 and SGLT2 mRNA and proteins in mice. However, no obvious change was observed in renal morphology.

CONCLUSION

Our study demonstrates a potential involvement of renal GLUT2 and SGLT2 in GDM pathology in an HFD-induced GDM mouse model, which further supports the role of renal GLUT2 and SGLT2 not only in T1DM and T2DM but also in GDM.

Metabolic Abnormalities in Diabetes and Kidney Disease: Role of Uremic Toxins

PURPOSE OF REVIEW

Chronic kidney disease (CKD) is characterized by the accumulation of uremic retention solutes (URS) and is associated with perturbations of glucose homeostasis even in absence of diabetes. The underlying mechanisms of insulin resistance, β cell failure, and increase risk of diabetes in CKD, however, remain unclear. Metabolomic studies reported that some metabolites are similar in CKD and diabetic kidney disease (DKD) and contribute to the progression to end-stage renal disease. We attempted to discuss the mechanisms involved in the disruption of carbohydrate metabolism in CKD by focusing on the specific role of URS.

RECENT FINDINGS

Recent clinical data have demonstrated a defect of insulin secretion in CKD. Several studies highlighted the direct role of some URS (urea, trimethylamine N-oxide (TMAO), p-cresyl sulfate, 3-carboxylic acid 4-methyl-5-propyl-2-furan propionic (CMPF)) in glucose homeostasis abnormalities and diabetes incidence. Gut dysbiosis has been identified as a potential contributor to diabetes and to the production of URS. The complex interplay between the gut microbiota, kidney, pancreas β cell, and peripheral insulin target tissues has brought out new hypotheses for the pathogenesis of CKD and DKD. The characterization of intestinal microbiota and its associated metabolites are likely to fill fundamental knowledge gaps leading to innovative research, clinical trials, and new treatments for CKD and DKD.

Adiposity and weight gain during pregnancy associate independently with behavior of infant rhesus monkeys (Macaca mulatta)

Growing evidence identifies maternal adiposity as a potentially modifiable risk factor for adverse neurodevelopment. This retrospective cohort analysis examined whether maternal prepregnancy adiposity and gestational weight gain were associated with behavioral outcomes in 173 rhesus macaque infants at the California National Primate Research Center. Dams conceived indoors, had uncomplicated pregnancies, delivered vaginally, and reared infants indoors. Infants underwent standardized biobehavioral analysis at 90-120 days of age from 3/2001-5/2015. Offspring of mothers with greater baseline adiposity or gestational weight gain exhibited a pattern of poor adaptability characterized by greater emotionality as the assessments proceeded, blunted affective response to a human intruder challenge, and reduced interest in novel stimuli which is associated with poorer social functioning later in life. They also had lower cortisol levels following dexamethasone suppression, perhaps a response to cortisol excess during gestation. These results amplify growing public health concerns implicating maternal adiposity in impaired fetal neurobehavioral programming.

Is 3-Carboxy-4-methyl-5-propyl-2-furanpropionate (CMPF) a Clinically Relevant Uremic Toxin in Haemodialysis Patients?

3-Carboxy-4-methyl-5-propyl-2-furanpropionate (CMPF) is a metabolite of furan fatty acid and a marker of fish oil intake. CMPF is described as a protein-bound uremic toxin and interacts with free oxygen radicals, which can induce cell damages. However, the clinical consequences of CMPF accumulation in haemodialysis patients remain poorly documented. The aims of this study are to investigate potential association between CMPF levels and (i) biochemical and nutritional parameters; (ii) cardiovascular events and (iii) mortality. Two hundred and fifty-two patients undergoing maintenance haemodialysis were included. Routine clinical biochemistry tests and assay for CMPF by HPLC technique were performed at the inclusion. Body composition parameters were measured using a bioimpedance spectroscopy method. The enrolled patients were prospectively monitored for cardiovascular events and mortality. CMPF level was positively correlated with nutritional parameters and lean mass and is significantly higher in patients without protein-energy wasting. However, the multivariate linear regression analysis indicated that CMPF level was not independently associated with albumin, prealbumin, creatinemia and body mass index. Elevated serum CMPF was not associated with mortality and cardiovascular morbidity. Our results indicate that CMPF is not a relevant uremic toxin in haemodialysis and in contrast could be a marker of healthy diet and omega 3 intakes.

microRNA-503 contribute to pancreatic beta cell dysfunction by targeting the mTOR pathway in gestational diabetes mellitus

Loss of pancreatic β cells is involved in pathogenesis of gestational diabetes mellitus (GDM). Recently, several studies have elucidated the connection between microRNAs (miRNAs) and diabetes mellitus (DM), but the role of miRNAs in GDM remains unclear. The aim of this study was to evaluate the potential functions of miRNAs in GDM and to investigate the underlying mechanisms of action. First, we explored the expression profile of miRNAs in placenta tissue from GDM patients using microarray. Validation analysis was performed in peripheral blood specimens using quantitative reverse transcription PCR (qRT-PCR). Then the role and regulating mechanism of miR-503 in weaken the function of pancreatic β cell was investigated. We found that miR-503 was markedly upregulated in placenta tissue from GDM patients, as elevated in peripheral blood specimens, and the high level was positively correlated to blood glucose concentration. Knockdown of miR-503 enhanced insulin secretion of pancreatic β-cells, promoted cell proliferation and protected cells from apoptosis, whereas overexpression of miR-503 showed the opposite effects. Furthermore, mammalian target of rapamycin (mTOR) was identified as a direct target of miR-503 and mTOR silencing could reverse the improving effects of miR-503 knockdown on insulin secretion and pancreatic β-cells proliferation. High expression of miR-503 in peripheral blood may be acted as a diagnosis biomarker of GDM. MiR-503 regulated functions of pancreatic β-cells by targeting the mTOR pathway, suggesting that targeting miR-503/mTOR axis could serve as a novel therapeutic target for GDM.

Furan fatty acids - Beneficial or harmful to health?

Furan fatty acids are found in plants, algae, and fish, and reported to have some positive health benefits, including anti-oxidant and anti-inflammatory activities, and inhibition of non-enzymatic lipid peroxidation. A major metabolite of furan fatty acids, 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid (CMPF), has been reported to be increased in patients who progress from prediabetes to type 2 diabetes, although CMPF is not necessarily associated with impaired glucose metabolism. Other studies report that CMPF levels are lower in subjects with diabetes than control subjects. Plasma CMPF levels increase in subjects who consume fish or fish oil, and in patients with renal failure. It is not known where furan fatty acids are converted to CMPF and it is speculated that this might be a result of microbiome activity. The plasma levels reported for CMPF in healthy, diabetic and patients with renal disease vary by factors of more than 100-fold within each of these three groups, so measurement error appears to be limiting the ability to interpret studies. This review explores these controversies and raises questions about whether CMPF is a marker for healthy diets or indeed associated with diabetes and renal health. The review concludes that, on balance, furan fatty acids are beneficial for health.

Circulating 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid (CMPF) levels are associated with hyperglycemia and β cell dysfunction in a Chinese population

Several recent clinical studies have suggested that the levels of circulating 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid (CMPF) are significantly higher in patients with gestational diabetes mellitus (GDM), impaired glucose tolerance (IGT), and type 2 diabetes mellitus (T2DM). This study recruited a total of 516 participants. The following patient populations were enrolled: 99 newly diagnosed cases with T2DM, 219 cases with prediabetes [82 with isolated impaired glucose tolerance (I − IGT), 66 with isolated impaired fasting glucose (I − IFG) and 71 with impaired glucose tolerance and impaired fasting glucose (IGT + IFG)], and 198 cases with normal glucose tolerance [NGT, including 99 first-degree relatives of type 2 diabetes patients (FDRs) and 99 non-FDRs]. We investigated the circulating CMPF levels in subjects with different glucose metabolism statuses and examined the potential link between CMPF and β cell function. Our results indicate that the serum CMPF levels were elevated in the prediabetes, T2DM, and FDRs groups compared to the NGT group. Additionally, the serum CMPF concentrations were independently and negatively associated with the triglyceride levels and Stumvoll first-phase insulin secretion index. Cumulatively, our findings suggest that the circulating CMPF levels can predict glycolipid metabolism disorders. Furthermore, elevated serum CMPF concentrations may determine hyperglycemia and β cell dysfunction.

Adiponectin Deficiency Impairs Maternal Metabolic Adaptation to Pregnancy in Mice

Hypoadiponectinemia has been widely observed in patients with gestational diabetes mellitus (GDM). To investigate the causal role of hypoadiponectinemia in GDM, adiponectin gene knockout (Adipoq-/- ) and wild-type (WT) mice were crossed to produce pregnant mouse models with or without adiponectin deficiency. Adenoviral vector-mediated in vivo transduction was used to reconstitute adiponectin during late pregnancy. Results showed that Adipoq-/- dams developed glucose intolerance and hyperlipidemia in late pregnancy. Increased fetal body weight was detected in Adipoq-/- dams. Adiponectin reconstitution abolished these metabolic defects in Adipoq-/- dams. Hepatic glucose and triglyceride production rates of Adipoq-/- dams were significantly higher than those of WT dams. Robustly enhanced lipolysis was found in gonadal fat of Adipoq-/- dams. Interestingly, similar levels of insulin-induced glucose disposal and insulin signaling in metabolically active tissues in Adipoq-/- and WT dams indicated that maternal adiponectin deficiency does not reduce insulin sensitivity. However, remarkably decreased serum insulin concentrations were observed in Adipoq-/- dams. Furthermore, β-cell mass, but not glucose-stimulated insulin release, in Adipoq-/- dams was significantly reduced compared with WT dams. Together, these results demonstrate that adiponectin plays an important role in controlling maternal metabolic adaptation to pregnancy.

Synthesis and Characterization of Urofuranoic Acids: In Vivo Metabolism of 2-(2-Carboxyethyl)-4-methyl-5-propylfuran-3-carboxylic Acid (CMPF) and Effects on in Vitro Insulin Secretion

CMPF (2-(2-carboxyethyl)-4-methyl-5-propylfuran-3-carboxylic acid) is a metabolite that circulates at high concentrations in type 2 and gestational diabetes patients. Further, human clinical studies suggest it might have a causal role in these diseases. CMPF inhibits insulin secretion in mouse and human islets in vitro and in vivo in rodents. However, the metabolic fate of CMPF and the relationship of structure to effects on insulin secretion have not been significantly studied. The syntheses of CMPF and analogues are described. These include isotopically labeled molecules. Study of these materials in vivo has led to the first observation of a metabolite of CMPF. In addition, a wide range of CMPF analogues have been prepared and characterized in insulin secretion assays using both mouse and human islets. Several molecules that influence insulin secretion in vitro were identified. The molecules described should serve as interesting probes to further study the biology of CMPF.

Circulating Betatrophin Levels and Gestational Diabetes Mellitus: A Systematic Review and Meta-Analysis

OBJECTIVE

The association between circulating betatrophin levels and gestational diabetes mellitus (GDM) is controversial. The aim of our study was to systematically review available literature linking betatrophin to GDM for a comprehensive understanding of the relationship between circulating betatrophin levels and GDM in human.

METHODS

PubMed, The Cochrane Library, Medline and CNKI were searched for studies published up to August 2016. Manual searches of references of the relevant original studies were conducted. Pooled estimates were measured using the fixed or random effect model. Overall effect was reported in a standard mean difference (SMD). All data were analyzed with Review Manager 5.3 and Stata 12.0.

RESULTS

Of 25 references reviewed, 8 studies met our inclusion criteria and contributed to meta-analysis. All the studies were used to evaluate the relationship between betatrophin levels in blood and GDM. Betatrophin levels were significantly elevated in women with GDM compared with those without GDM (SMD = 1.05; 95% CI: 0.41-1.68, P = 0.001). This evidence was more consistent among women with betatrophin blood draw during the third trimester (SMD = 1.3, 95% CI: 1-1.61, P < 0.001) and for women BMI ≥ 28 kg/m2 (SMD = 1.53, 95% CI: 1.30-1.75, P < 0.001).

CONCLUSIONS

The evidences from this meta-analysis indicated that the levels of circulating betatrophin were significantly elevated among women with GDM compared with women with normal glucose tolerance, especially with BMI ≥ 28 kg/m2 and in the third trimester.

Metabolomics and Metabolic Diseases: Where Do We Stand?

Metabolomics, or the comprehensive profiling of small molecule metabolites in cells, tissues, or whole organisms, has undergone a rapid technological evolution in the past two decades. These advances have led to the application of metabolomics to defining predictive biomarkers for incident cardiometabolic diseases and, increasingly, as a blueprint for understanding those diseases' pathophysiologic mechanisms. Progress in this area and challenges for the future are reviewed here.

Serum selenium level and gestational diabetes mellitus: a systematic review and meta-analysis

Background

The association between serum selenium level and gestational diabetes mellitus (GDM) is controversial. The aim of our study was to systematically review available literature linking selenium to GDM for a comprehensive understanding of the relationship between serum selenium level and GDM in human.

Methods

PubMed, The Cochrane Library and Medline were searched for studies published up to August 2016. Manual searches of references of the relevant original studies were carried out. Pooled estimates were measured using the fixed or random effect model. Overall effect was reported in a standard mean difference (SMD). All data were analyzed with Review Manager 5.3 and Stata 12.0.

Results

Of 44 references reviewed, seven studies involving 569 patients met our inclusion criteria and contributed to meta-analysis. All the studies were used to evaluate the relationship between serum selenium level and GDM. Selenium level was significantly lower in women with GDM than those without GDM (SMD = −1.17; 95 % CI: −1.98 to −0.35, P = 0.005). Subgroup analysis showed that such trend was consistent within the non-Caucasian population (Asia: SMD = −2.82; 95 % CI: −5.21 to −0.43, P = 0.02; Africa: SMD = −0.56; 95 % CI: −1.07 to −0.05, P = 0.03) and in the third trimester (SMD = −1.78; 95 % CI: −3.04 to −0.52, P = 0.006), but not within the Caucasian population (Europe: SMD = −0.6; 95 % CI: −1.98 to 0.78, P = 0.39) or in the second trimester (SMD = −0.68; 95 % CI: −1.6 to 0.25, P = 0.15).

Conclusions

The available evidences suggested that serum selenium level was lower in women with GDM than those with normal glucose tolerance, especially within the non-Caucasian population and in the third trimester. However, well-designed prospective studies are needed to understand dynamic associations between selenium status and GDM risk.