Uric Acid and Xanthine Levels in Pregnancy Complicated by Gestational Diabetes Mellitus-The Effect on Adverse Pregnancy Outcomes

Elevated uric acid in gestational diabetes and its risk on pregnancy outcomes

Background

Over the past few years, gestational diabetes mellitus has become more common. According to earlier research, gestational diabetes mellitus is linked to higher uric acid levels, and gestational hyperuricemia is linked to poor maternal and neonatal outcomes.

Aim and objectives

To assess the influence of elevated uric acid >5 mg/dl on pregnancy outcomes such as neonatal weight, respiratory distress, preterm delivery, neonatal intensive care unit admission, premature membrane rupture, oligohydramnios, cesarean section, and intensive care admission for mothers.

Setting and methods

It is a prospective cohort study, carried out at obstetric/family medicine outpatient clinics, Cairo University Hospitals on 221 pregnant females with gestational diabetes mellitus in their third trimester of pregnancy, selected by random sampling, performed structured interviews, and tested for serum uric acid level and were separated into two groups, those with elevated uric acid >5 mg/dl (121) and those without elevated uric acid ⩽5 mg/dl (100) patients and then followed up until delivery in Cairo University Hospitals for collecting pregnancy outcome data.

Results

There were statistically significant differences between the antepartum uric acid and neonatal complications, maternal complications, preterm, macrosomia, neonatal intensive care unit admission, premature rupture of membranes, oligohydramnios, and cesarean section between both groups.

Conclusions

This study showed that elevated serum uric acid >5 mg/dl can predict the incidence of maternal and neonatal problems in gestational diabetes mellitus including preterm, macrosomia, neonatal intensive care unit admission, premature rupture of membranes, oligohydramnios, and cesarean section.

Association of maternal serum uric acid levels with LBW/SGA: a large retrospective cohort study

BACKGROUND

Elevated maternal serum uric acid (UA) levels were associated with adverse perinatal outcomes. This study aimed to examine the association between UA and the risk of low birth weight (LBW) / small for gestational age (SGA).

METHODS

A cohort study of women delivered in Shanghai maternity hospital was included between 2017 and 2021. Electronic medical records were utilized to extract information and antenatal care records. The cut-off value of UA was 360 μmol/L. The outcome was LBW/SGA, with LBW defined as birth weight below 2500 g and SGA indicating birth weight below the 10th percentile of average weight for gestational age. The assessment of SGA was based on the Chinese standard curve for birth weight at various gestational ages. Univariate, multivariate logistic regression models, restricted cubic spline were used in this study, with adjustments made for confounding factors.

RESULTS

Sixty-nine thousand six hundred seventy-four live births and singleton pregnancies were included. The ratio of LBW/SGA was 3.3%/9%. Maternal UA levels were significantly negatively correlated with birth weight. High UA levels were associated with high risk of LBW/SGA, especially in third trimester. In BMI < 25 group, the risk of LBW increased to 2.35-fold (95%CI, 1.66-3.31) in hyperuricemic group (UA > 360 μmol/L). The SGA risk was 1.66-fold (95%CI, 1.37-2.00). Gestational hypertension (GH) with hyperuricemica increased the risk of LBW (aOR = 4.00, 95%CI, 2.01-7.93) and SGA (aOR = 2.63, 95%CI, 1.83-3.78). Preeclampsia (PE) with hyperuricemia increased the risk of LBW (aOR = 1.38, 95%CI, 0.63-3.03) and SGA (aOR = 1.81, 95%CI, 1.18-2.78). In delivery gestational week (DGW) ≥ 37 group, if UA > 360 μmol/L, the incidence of LBW increased to 2.46-fold (95%CI, 1.62, 3.73) and the incidence of SGA increased to 1.52-fold (95%CI, 1.24, 1.87). In DGW < 37 group, if UA > 360 μmol/L, the incidence of LBW increased to 2.70-fold (95%CI, 1.92, 3.80) and the incidence of SGA increased to 2.13-fold(95%CI, 1.50, 3.02).

CONCLUSIONS

The study found an inverse correlation between UA levels and birth weight. High UA levels were associated with increased risk of LBW/SGA, particularly in third trimester. GH or PE complicated by hyperuricemia were found to have significantly higher risk of developing LBW/SGA. This relationship also existed in pregnant women with BMI < 25.

New perspective on first-trimester serum uric acid level in predicting the risk of gestational diabetes mellitus

This study aimed to investigate the correlation between serum uric acid (UA) and gestational diabetes mellitus (GDM) during the first trimester and provide a new perspective for the prevention and treatment of GDM. Based on the diagnostic criteria of gestational diabetes of the International Association of Diabetes and Pregnancy Study Groups, 1744 and 4256 patients were enrolled in the GDM and normal glucose tolerance (NGT) groups. Four groups were constituted based on the quartile of first-trimester serum UA (UA) level, and the differences in each indicator between groups were compared. Logistic regression was used to analyze the effects of UA level on GDM risk. The rate of GDM in the UA quartile changed from low to high. Significant differences were also observed in fasting plasma glucose level, 1 h post glucose and 2 h post glucose levels, in all the groups (P < 0.05), which increased with the UA level. UA level were independent risk factors for GDM. The best threshold of GDM predicted by the first-trimester UA level was 226.55 μmol/L. The first-trimester UA level in patients with GDM was relatively higher and was an independent risk factor for GDM.

Pre-pregnancy body mass index combined with peripheral blood PLGF, DCN, LDH, and UA in a risk prediction model for pre-eclampsia

Objective

This study analyzes the levels of peripheral blood placental growth factor (PLGF), body mass index (BMI), decorin (DCN), lactate dehydrogenase (LDH), uric acid (UA), and clinical indicators of patients with preeclampsia (PE), and establishes a predictive risk model of PE, which can provide a reference for early and effective prediction of PE.

Methods

81 cases of pregnant women with PE who had regular prenatal checkups and delivered in Jinshan Branch of Shanghai Sixth People's Hospital from June 2020 to December 2022 were analyzed, and 92 pregnant women with normal pregnancies who had their antenatal checkups and delivered at the hospital during the same period were selected as the control group. Clinical data and peripheral blood levels of PLGF, DCN, LDH, and UA were recorded, and the two groups were subjected to univariate screening and multifactorial logistic regression analysis. Based on the screening results, the diagnostic efficacy of PE was evaluated using the receiver operating characteristic (ROC) curve. Risk prediction nomogram model was constructed using R language. The Bootstrap method (self-sampling method) was used to validate and produce calibration plots; the decision curve analysis (DCA) was used to assess the clinical benefit rate of the model.

Results

There were statistically significant differences in age, pre-pregnancy BMI, gestational weight gain, history of PE or family history, family history of hypertension, gestational diabetes mellitus, and history of renal disease between the two groups (P < 0.05). The results of multifactorial binary logistic stepwise regression revealed that peripheral blood levels of PLGF, DCN, LDH, UA, and pre-pregnancy BMI were independent influences on the occurrence of PE (P < 0.05). The area under the curve of PLGF, DCN, LDH, UA levels and pre-pregnancy BMI in the detection of PE was 0.952, with a sensitivity of 0.901 and a specificity of 0.913, which is better than a single clinical diagnostic indicator. The results of multifactor analysis were constructed as a nomogram model, and the mean absolute error of the calibration curve of the modeling set was 0.023, suggesting that the predictive probability of the model was generally compatible with the actual value. DCA showed the predictive model had a high net benefit in the range of 5% to 85%, suggesting that the model has clinical utility value.

Conclusion

The occurrence of PE is related to the peripheral blood levels of PLGF, DCN, LDH, UA and pre-pregnancy BMI, and the combination of these indexes has a better clinical diagnostic value than a single index. The nomogram model constructed by using the above indicators can be used for the prediction of PE and has high predictive efficacy.

Does the Micronutrient Molybdenum Have a Role in Gestational Complications and Placental Health?

Molybdenum is an essential trace element for human health and survival, with molybdenum-containing enzymes catalysing multiple reactions in the metabolism of purines, aldehydes, and sulfur-containing amino acids. Recommended daily intakes vary globally, with molybdenum primarily sourced through the diet, and supplementation is not common. Although the benefits of molybdenum as an anti-diabetic and antioxidant inducer have been reported in the literature, there are conflicting data on the benefits of molybdenum for chronic diseases. Overexposure and deficiency can result in adverse health outcomes and mortality, although physiological doses remain largely unexplored in relation to human health. The lack of knowledge surrounding molybdenum intake and the role it plays in physiology is compounded during pregnancy. As pregnancy progresses, micronutrient demand increases, and diet is an established factor in programming gestational outcomes and maternal health. This review summarises the current literature concerning varied recommendations on molybdenum intake, the role of molybdenum and molybdoenzymes in physiology, and the contribution these play in gestational outcomes.

Serum uric acid and the risk of gestational diabetes mellitus: a systematic review and meta-analysis

AIMS

Serum uric acid (SUA) is considered as a risk factor for gestational diabetes mellitus (GDM). However, current studies showed inconsistent results. This study aimed to explore the relationship between SUA levels and GDM risk.

METHODS

Eligible studies were retrieved from PubMed, Web of Science, Embase, China National Knowledge Infrastructure, and Wanfang databases up to November 1, 2022. The pooled standardized mean difference (SMD) and 95% confidence interval (CI) were used to represent the difference in SUA levels between GDM women and controls. The combined odds ratios (OR) and 95% CI were applied to assess association between SUA levels and GDM risk. Subgroup analyses were conducted on study continents, design, and quality, detection time of SUA, and GDM diagnostic criteria.

RESULTS

Totally 11 studies including five case-control and six cohort studies, in which 80,387 pregnant women with 9815 GDM were included. The overall meta-analysis showed that the mean SUA level in GDM group was significantly higher than in controls (SMD = 0.423, 95%CI = 0.019-0.826, p = .040, I² = 93%). Notably, pregnant women with elevated levels of SUA had a significantly increased risk of GDM (OR = 1.670, 95%CI = 1.184-2.356, p = .0035, I² = 95%). Furthermore, subgroup analysis performed on the detection time of SUA showed a significant difference in the association between SUA and GDM risk within different trimesters (1st trimester: OR = 3.978, 95%CI = 2.177-7.268; 1st to 2nd trimester: OR = 1.340, 95%CI = 1.078-1.667; p between subgroups <.01).

CONCLUSIONS

Elevated SUA was positively associated with GDM risk, particularly in the 1st trimester of pregnancy. Further studies with high quality are required to validate the findings of this study.

Characterizing and Evaluating Diurnal Salivary Uric Acid Across Pregnancy Among Healthy Women

Uric acid levels during pregnancy have been examined as a potential indicator of risk for gestational diabetes mellites, hypertension, and related adverse birth outcomes. However, evidence supporting the utility of serum uric acid levels in predicting poor maternal and fetal health has been mixed. The lack of consistent findings may be due to limitations inherent in serum-based biomeasure evaluations, such as minimal repeated assessments and variability in the timing of these assessments. To address these gaps, we examined repeated measurements of diurnal salivary uric acid (sUA) levels in a sample of 44 healthy women across early-mid and late pregnancy. We assessed potential covariates and confounds of sUA levels and diurnal trajectories, as well as associations between maternal weight gain and blood pressure during pregnancy and sUA concentrations. Using multilevel linear models, we found sUA increased across pregnancy and displayed a robust diurnal pattern with the highest concentrations at waking, a steep decline in the early morning, and decreasing levels across the day. Maternal pre-pregnancy BMI, age, prior-night sleep duration, and fetal sex were associated with sUA levels and/or diurnal slopes. Maternal blood pressure and gestational weight gain also showed significant associations with sUA levels across pregnancy. Our results expand upon those found with serum UA measurements. Further, they demonstrate the feasibility of using at-home, minimally-invasive saliva sampling procedures to track UA levels across pregnancy with potential applications for the long-term monitoring of maternal cardiometabolic risk.

Metabolites involved in purine degradation, insulin resistance, and fatty acid oxidation are associated with prediction of Gestational diabetes in plasma

INTRODUCTION

Gestational diabetes mellitus (GDM) significantly increases maternal and fetal health risks, but factors predictive of GDM are poorly understood.

OBJECTIVES

Plasma metabolomics analyses were conducted in early pregnancy to identify potential metabolites associated with prediction of GDM.

METHODS

Sixty-eight pregnant women with overweight/obesity from a clinical trial of a lifestyle intervention were included. Participants who developed GDM (n = 34; GDM group) were matched on treatment group, age, body mass index, and ethnicity with those who did not develop GDM (n = 34; Non-GDM group). Blood draws were completed early in pregnancy (10-16 weeks). Plasma samples were analyzed by UPLC-MS using three metabolomics assays.

RESULTS

One hundred thirty moieties were identified. Thirteen metabolites including pyrimidine/purine derivatives involved in uric acid metabolism, carboxylic acids, fatty acylcarnitines, and sphingomyelins (SM) were different when comparing the GDM vs. the Non-GDM groups (p < 0.05). The most significant differences were elevations in the metabolites' hypoxanthine, xanthine and alpha-hydroxybutyrate (p < 0.002, adjusted p < 0.02) in GDM patients. A panel consisting of four metabolites: SM 14:0, hypoxanthine, alpha-hydroxybutyrate, and xanthine presented the highest diagnostic accuracy with an AUC = 0.833 (95% CI: 0.572686-0.893946), classifying as a "very good panel".

CONCLUSION

Plasma metabolites mainly involved in purine degradation, insulin resistance, and fatty acid oxidation, were altered in early pregnancy in connection with subsequent GDM development.

Genetically predicted serum uric acid levels and the risk of coronary artery disease in patients with diabetes: A Mendelian randomization study

BACKGROUND AND AIMS

Serum uric acid (SUA) levels have been reported to be associated with an increased risk of coronary artery disease (CAD) among patients with diabetes in observational study. Whether this relationship is causal remains unclear. The current study aimed to explore the causal association between SUA and the risk of CAD in patients with diabetes.

METHODS AND RESULTS

A two-sample Mendelian randomization (MR) approach was employed to evaluate the causal effect of SUA on the risk of CAD in patients with diabetes. A total of 28 single nucleotide polymorphisms (SNPs) related to SUA were identified as instruments. Genetic association with CAD were obtained from a recently published genome-wide association study (GWAS) of 15,666 patients with diabetes (3968 CAD cases and 11,696 controls). The fixed-effects inverse variance-weighted method was employed to estimate the causal effect for the primary analysis, and other robust methods were employed for sensitivity analyses. In addition, the whole analyses were repeated using 9 non-pleiotropic SNPs. Genetic determined SUA levels were not significantly associated with the risk of CAD in patients with diabetes in the primary analysis (odds ratio = 1.13, 95% confidence interval: 0.98-1.16, P = 0.09). Consistent results were observed in the sensitivity analyses using various robust methods. In addition, this finding was confirmed by the repeated analyses using 9 non-pleiotropic SNPs.

CONCLUSIONS

This two-sample MR study does not support a causal effect of genetically predicted SUA levels on the risk of CAD in patients with diabetes.

Uric acid participating in female reproductive disorders: a review

Uric acid (UA) is the end metabolic product of purine metabolism. Early on, UA was considered to be a metabolite with a certain antioxidant capacity. As research has progressed, other properties of UA have been explored, and its association with many diseases has been found. The association between UA and kidney disease and cardiovascular disease is well established; however, there is still a paucity of reviews on the association between UA and the female reproductive system. An increasing number of epidemiological studies have shown elevated serum UA levels in patients with polycystic ovary syndrome (PCOS), endometriosis, etc. Additionally, serum UA can be used as a predictor of pregnancy complications and adverse foetal outcomes. An increasing number of animal experiments and clinical studies have revealed possible mechanisms related to the involvement of UA in certain female reproductive disorders: oxidative stress, chronic inflammation, mitochondrial dysfunction, etc. This article reviews the current mainstream mechanisms regarding the pathogenesis of UA and the role of UA in certain specific female reproductive disorders (direct involvement in the development of certain diseases or enhancement of other risk factors) in the hope of contributing to clinical prevention, diagnosis, treatment and improvement in prognosis.

Nobiletin exerts anti-diabetic and anti-inflammatory effects in an in vitro human model and in vivo murine model of gestational diabetes

Gestational diabetes mellitus (GDM) is a global health issue, whereby pregnant women are afflicted with carbohydrate intolerance with first onset during pregnancy. GDM is characterized by maternal peripheral insulin resistance, thought to be driven by low-grade maternal inflammation. Nobiletin, a polymethoxylated flavonoid, possesses potent glucose-sensitizing and anti-inflammatory properties; however, its effects in GDM have not been assessed. The present study aimed to determine the effects of nobiletin on glucose metabolism and inflammation associated with GDM in both in vitro human tissues and an in vivo animal model of GDM. In vitro, treatment with nobiletin significantly improved TNF-impaired glucose uptake in human skeletal muscle, and suppressed mRNA expression and protein secretion of pro-inflammatory cytokines and chemokines in human placenta and visceral adipose tissue (VAT). Mechanistically, nobiletin significantly inhibited Akt and Erk activation in placenta, and NF-κB activation in VAT. In vivo, GDM mice treated with 50 mg/kg nobiletin daily via oral gavage from gestational day (gd) 1-17 or via i.p. injections from gd 10-17 significantly improved glucose tolerance. Pregnant GDM mice treated with nobiletin from either gd 1-17 or gd 10-17 exhibited significantly suppressed mRNA expression of pro-inflammatory cytokines and chemokines in placenta, VAT and subcutaneous adipose tissue (SAT). Using a quantitative mass spectrometry approach, we identified differentially abundant proteins associated with the effect of nobiletin in vivo. Together, these studies demonstrate that nobiletin improves glucose metabolism and reduces inflammation associated with GDM and may be a novel therapeutic for the prevention of GDM.

High-Protein Diet Induces Hyperuricemia in a New Animal Model for Studying Human Gout

Hyperuricemia is a central risk factor for gout and increases the risk for other chronic diseases, including cardiometabolic disease, kidney disease, and hypertension. Overproduction of urate is one of the main reasons for hyperuricemia, and dietary factors including seafoods, meats, and drinking are contributed to the development of it. However, the lack of a suitable animal model for urate metabolism is one of the main reasons for the delay and limitations of hyperuricemia research. Combining evolutionary biological studies and clinical studies, we conclude that chicken is a preferred animal model for hyperuricemia. Thus, we provided chickens a high-protein diet (HPD) to evaluate the changes in the serum urate levels in chickens. In our study, the HPD increased the serum urate level and maintained it at a long-term high level in chickens. Long-term high serum urate levels induced an abnormal chicken claw morphology and the precipitation of monosodium urate (MSU) in joint synovial fluid. In addition, a long-term HPD also decreased the glomerular filtration rate and induced mild renal injury. Most importantly, allopurinol and probenecid displayed the positive effects in decreasing serum urate and then attenuated hyperuricemia in chicken model. These findings provide a novel model for hyperuricemia and a new opportunity to further investigate the effects of long-term hyperuricemia on other metabolic diseases.