Role of Oxidative Stress and Inflammation in Gestational Diabetes Mellitus

Gestational diabetes mellitus, not obesity, triggers postpartum brain inflammation and premature aging in Sprague-Dawley rats

Previous studies showed that women with gestational diabetes mellitus (GDM) are susceptible to cognitive dysfunction. We investigated the effects of GDM on brain pathologies and premature brain aging in rats. Seven-week-old female Sprague-Dawley rats were fed a normal diet (ND) or a high-fat diet (HFD) after two weeks of acclimatization. On pregnancy day 0, HFD-treated rats received streptozotocin (GDM group) or vehicle (Obese mothers). ND-treated rats received vehicle (ND-control mothers). On postpartum day 21, brains and blood were collected. The GDM group showed increased inflammatory and premature aging markers, mitochondrial changes, and compensatory increases in the blood-brain barrier and synaptic proteins in the prefrontal cortex and hippocampus. GDM triggers maternal brain inflammation and premature aging, suggesting compensatory mechanisms may protect against these effects.

Changes in Oxidative Stress Markers in Pregnant Women of Advanced Maternal Age with Gestational Diabetes and Their Predictive Value for Neurodevelopmental Impact

Objective

To explore the relationship between changes in oxidative stress markers in pregnant women of advanced maternal age with gestational diabetes mellitus (GDM) and adverse pregnancy outcomes and neonatal neurodevelopment, as well as their predictive value.

Methods

Two hundred pregnant women of advanced maternal age were selected and divided into Group A (normal blood sugar) and Group B (GDM) based on the 75 g (Oral Glucose Tolerance Test) OGTT results. Oxidative stress markers were measured, and pregnancy outcomes and neonatal Neonatal Behavioral Assessment Scale (NABA) scores were recorded.

Results

Malondialdehyde (MDA) levels in Group B were higher than those in Group A, while Glutathione (GSH) and Superoxide Dismutase (SOD) levels were lower. Group B had higher rates of adverse pregnancy outcomes and neurological abnormalities than Group A. The Area Under the Curve (AUC) values for serum MDA, GSH, and SOD levels combined prediction were higher than those for individual predictions (P<0.05).

Conclusion

Oxidative stress markers in pregnant women of advanced maternal age with GDM are associated with adverse pregnancy outcomes and neonatal abnormalities, and combined prediction has good predictive efficiency (AUC>0.7).

MiR-142-5p mediated Nrf2 dysregulation in gestational diabetes mellitus and its impact on placental angiogenesis

INTRODUCTION

Gestational diabetes mellitus (GDM) presents significant risks during pregnancy, including adverse perinatal outcomes and placental dysfunction. Impaired angiogenesis, involving crucial factors like Vascular Endothelial Growth Factor (VEGF), contributes to these complications. The Nrf2/Keap1 pathway, crucial for vascular redox homeostasis, has been linked to GDM-associated angiogenesis dysregulation.

METHODS

This study aimed to investigate the molecular mechanisms underlying placental Nrf2 regulation, focusing on angiomiRs, key regulators of angiogenesis in GDM. Computational analysis identified miR-142-5p targeting Nrf2 mRNA. Expression levels of miR-142-5p were assessed in GDM placenta and correlated with Nrf2 expression. Experimental validation utilized human trophoblastic cell lines (BeWo) exposed to hyperglycemic conditions, assessing the effects of anti-miR-142 transfection on Nrf2 expression and angiogenic marker levels.

RESULTS

miR-142-5p expression was significantly downregulated in GDM placenta, correlating positively with Nrf2 expression. In BeWo cells exposed to hyperglycemia, anti-miR-142 transfection notably increased Nrf2 expression alongside angiogenic marker levels, confirming the computational predictions.

DISCUSSION

Our findings highlight the pivotal role of miRNAs in GDM-associated impaired angiogenesis by modulating Nrf2 expression. Understanding these molecular mechanisms provides insights into potential therapeutic targets for improving pregnancy outcomes in GDM cases.

Probiotic therapy as a promising strategy for gestational diabetes mellitus management

INTRODUCTION

Gestational diabetes mellitus (GDM) has become the most common pregnancy medical complication, and its prevalence has increased in recent years. The GDM treatment primarily relies on adopting healthy eating habits, physical exercise, and insulin therapy. However, using probiotics to modulate the gut microbiota has been the subject of clinical trials as a promising therapeutic strategy for GDM management.

AREAS COVERED

Due to the adverse effects of gut dysbiosis in women with GDM, strategies targeting the gut microbiota to mitigate hyperglycemia, low-grade inflammation, and adverse pregnancy outcomes have been explored. Probiotic supplementation may improve glucose metabolism, lipid profile, oxidative stress, inflammation, and blood pressure in women with GDM. Furthermore, decreased fasting blood glucose, insulin resistance, and inflammatory markers, such as TNF-α and CRP, as well as increased total antioxidant capacity, lipid profile modulation, and improved blood pressure in women with GDM, are some of the important results reported in the available literature.

EXPERT OPINION

To fill the knowledge gap, further studies are needed focusing on modulating gut microbiota composition and metabolic activity and their systemic repercussions in GDM.

Analysis of Risk Factors Associated with Gestational Diabetes Mellitus: A Retrospective Case-Control Study

Objective

Gestational diabetes mellitus (GDM) is a complication of abnormal glucose tolerance during pregnancy, with incidence is on the rise. There are inconsistent results on the risks of GDM and it has not been reported in our region. The purpose of this study is to explore the risk factors of GDM.

Methods

A total of 383 pregnant women were analyzed, including 67 (17.5%) pregnant women with GDM and 316 (82.5%) with normal glucose tolerance (NGT). The relationship of personal history, family history and reproductive history of pregnant women, the levels of alpha-fetoprotein (AFP), human chorionic gonadotropin (HCG), inflammatory markers in blood cell analysis at the first prenatal examination, and fetal ultrasound indices and the risk of GDM were analyzed.

Results

The fetal biparietal diameter, head circumference, and femur length were negatively correlated with HCG level, but not inflammatory markers. The proportion of pregnant women aged ≥30 years old, body mass index (BMI) in early pregnancy≥24.0 kg/m2, history of polycystic ovary syndrome (PCOS), cesarean section, adverse pregnancy, and oral contraceptive use, and pregnant women who conceived through assisted reproduction in GDM group were higher than those in NGT group. Logistic regression analysis showed that age of pregnant woman ≥30 years old (≥30 vs <30 years old, odds ratio (OR): 2.142, 95% confidence interval (CI): 1.183-3.878, p=0.012), BMI≥24.0 kg/m2 (≥24.0 kg/m2 vs 18.5-23.9 kg/m2, OR: 1.887, 95% CI: 1.041-3.420, p=0.036), history of adverse pregnancy (yes vs no, OR: 1.969, 95% CI: 1.022-3.794, p=0.043), and history of oral contraceptive use (yes vs no, OR: 2.868, 95% CI: 1.046-7.863, p=0.041) were associated with GDM.

Conclusion

Age of pregnant woman ≥30 years old, BMI≥24.0 kg/m2, history of adverse pregnancy and oral contraceptive use were independent risk factors for GDM.

Hydroxychloroquine as an Adjunct Therapy for Diabetes in Pregnancy

This review discusses the pathophysiology of diabetes in pregnancy in relation to the placental function. We review the potential use of hydroxychloroquine in improving pregnancy outcomes affected by diabetes. The review focuses on the mechanism of action of hydroxychloroquine and its potential effects on diabetes. There are several pathways in which hydroxychloroquine mediates its effects: through the inflammasome complex, inflammatory cytokines, oxidative stress, modulatory effects, and antihyperglycemic effects. As a safe drug to be used in pregnancy, it is worth exploring the possible use hydroxychloroquine as an adjunct treatment to the current therapy of diabetes in pregnancy.

Unravelling the Metabolic Underpinnings of Gestational Diabetes Mellitus: A Comprehensive Mendelian Randomisation Analysis Identifying Causal Metabolites and Biological Pathways

BACKGROUND

Gestational diabetes mellitus (GDM) has a strong genetic predisposition. Integrating metabolomics with Mendelian randomisation (MR) analysis offers a potent method to uncover the metabolic factors causally linked to GDM pathogenesis.

OBJECTIVES

This study aims to identify specific metabolites and metabolic pathways causally associated with GDM susceptibility through a comprehensive MR analysis. Additionally, it seeks to explore the potential of these identified metabolites as circulating biomarkers for early GDM detection and risk assessment. Furthermore, it aims to evaluate the implicated metabolic pathways as potential therapeutic targets for preventive or interventional strategies against GDM.

METHODS

A two-sample MR study was conducted using summary statistics from a metabolite genome-wide association study (GWAS) of 8299 individuals and a GDM GWAS comprising 13,039 cases and 197,831 controls. Rigorous criteria were applied to select robust genetic instruments for 850 metabolites.

RESULTS

MR analysis revealed 47 metabolites exhibiting putative causal associations with GDM risk. Among these, five metabolites demonstrated statistically significant associations after multiple-testing correction: Beta-citrylglutamate, Isobutyrylcarnitine (c4), 1,2-dilinoleoyl-GPC (18:2/18:2), Alliin and Cis-3,4-methyleneheptanoylcarnitine. Importantly, all these metabolites exhibited protective effects against GDM development. Additionally, metabolic pathway enrichment analysis implicated the methionine metabolism and spermidine and spermine biosynthesis pathways in the pathogenesis of GDM.

CONCLUSION

This comprehensive MR study has robustly identified specific metabolites and metabolic pathways with causal links to GDM susceptibility. These findings provide novel insights into the metabolic underpinnings of GDM aetiology and offer promising translational implications. The identified metabolites could serve as potential circulating biomarkers for early detection and risk stratification, while the implicated metabolic pathways may represent therapeutic targets for preventive or interventional strategies against GDM.

The interplay between cytokines, inflammation, and antioxidants: mechanistic insights and therapeutic potentials of various antioxidants and anti-cytokine compounds

Cytokines regulate immune responses essential for maintaining immune homeostasis, as deregulated cytokine signaling can lead to detrimental outcomes, including inflammatory disorders. The antioxidants emerge as promising therapeutic agents because they mitigate oxidative stress and modulate inflammatory pathways. Antioxidants can potentially ameliorate inflammation-related disorders by counteracting excessive cytokine-mediated inflammatory responses. A comprehensive understanding of cytokine-mediated inflammatory pathways and the interplay with antioxidants is paramount for developing natural therapeutic agents targeting inflammation-related disorders and helping to improve clinical outcomes and enhance the quality of life for patients. Among these antioxidants, curcumin, vitamin C, vitamin D, propolis, allicin, and cinnamaldehyde have garnered attention for their anti-inflammatory properties and potential therapeutic benefits. This review highlights the interrelationship between cytokines-mediated disorders in various diseases and therapeutic approaches involving antioxidants.

In Utero Extrahepatic Bile Duct Damage and Repair: Implications for Biliary Atresia

Biliary atresia (BA) is a cholangiopathy affecting the extrahepatic bile duct (EHBD) of newborns. The etiology and pathophysiology of BA are not fully understood; however, multiple causes of damage and obstruction of the neonatal EHBD have been identified. Initial damage to the EHBD likely occurs before birth. We discuss how different developmental stages in utero and birth itself could influence the susceptibility of the fetal EHBD to damage and a damaging wound-healing response. We propose that a damage-repair response of the fetal and neonatal EHBD involving redox stress and a program of fetal wound healing could-regardless of the cause of the initial damage-lead to either obstruction and BA or repair of the duct and recovery. This overarching concept should guide future research targeted toward identification of factors that contribute to recovery as opposed to progression of injury and fibrosis. Viewing BA through the lens of an in utero damage-repair response could open up new avenues for research and suggests exciting new therapeutic targets.

Association of DNA Methylation with Infant Birth Weight in Women with Gestational Diabetes

Offspring exposed to gestational diabetes mellitus (GDM) exhibit greater adiposity at birth. This early-life phenotype may increase offspring risk of developing obesity, metabolic syndrome, type 2 diabetes, and cardiovascular disease later in life. Infants born to women with GDM have a dysregulation of several hormones, cytokines, and growth factors related to fetal fat mass growth. One of the molecular mechanisms of GDM influencing these factors is epigenetic alterations, such as DNA methylation (DNAm). This review will examine the role of DNAm as a potential biomarker for monitoring fetal growth during pregnancy in women with GDM. This information is relevant since it may provide useful new biomarkers for the diagnosis, prognosis, and treatment of fetal growth and its later-life health consequences.

Melatonin in Human Breast Milk and Its Potential Role in Circadian Entrainment: A Nod towards Chrononutrition?

Breastfeeding is the most appropriate source of a newborn's nutrition; among the plethora of its benefits, its modulation of circadian rhythmicity with melatonin as a potential neuroendocrine transducer has gained increasing interest. Transplacental transfer assures melatonin provision for the fetus, who is devoid of melatonin secretion. Even after birth, the neonatal pineal gland is not able to produce melatonin rhythmically for several months (with an even more prolonged deficiency following preterm birth). In this context, human breast milk constitutes the main natural source of melatonin: diurnal dynamic changes, an acrophase early after midnight, and changes in melatonin concentrations according to gestational age and during the different stages of lactation have been reported. Understudied thus far are the factors impacting on (changes in) melatonin content in human breast milk and their clinical significance in chronobiological adherence in the neonate: maternal as well as environmental aspects have to be investigated in more detail to guide nursing mothers in optimal feeding schedules which probably means a synchronized instead of mistimed feeding practice. This review aims to be thought-provoking regarding the critical role of melatonin in chrononutrition during breastfeeding, highlighting its potential in circadian entrainment and therefore optimizing (neuro)developmental outcomes in the neonatal setting.

High glucose-induced p66Shc mitochondrial translocation regulates autophagy initiation and autophagosome formation in syncytiotrophoblast and extravillous trophoblast

BACKGROUND

p66Shc, as a redox enzyme, regulates reactive oxygen species (ROS) production in mitochondria and autophagy. However, the mechanisms by which p66Shc affects autophagosome formation are not fully understood.

METHODS

p66Shc expression and its location in the trophoblast cells were detected in vivo and in vitro. Small hairpin RNAs or CRISPR/Cas9, RNA sequencing, and confocal laser scanning microscope were used to clarify p66Shc's role in regulating autophagic flux and STING activation. In addition, p66Shc affects mitochondrial-associated endoplasmic reticulum membranes (MAMs) formation were observed by transmission electron microscopy (TEM). Mitochondrial function was evaluated by detected cytoplastic mitochondrial DNA (mtDNA) and mitochondrial membrane potential (MMP).

RESULTS

High glucose induces the expression and mitochondrial translocation of p66Shc, which promotes MAMs formation and stimulates PINK1-PRKN-mediated mitophagy. Moreover, mitochondrial localized p66Shc reduces MMP and triggers cytosolic mtDNA release, thus activates cGAS/STING signaling and ultimately leads to enhanced autophagy and cellular senescence. Specially, we found p66Shc is required for the interaction between STING and LC3II, as well as between STING and ATG5, thereby regulates cGAS/STING-mediated autophagy. We also identified hundreds of genes associated several biological processes including aging are co-regulated by p66Shc and ATG5, deletion either of which results in diminished cellular senescence.

CONCLUSION

p66Shc is not only implicated in the initiation of autophagy by promoting MAMs formation, but also helps stabilizing active autophagic flux by activating cGAS/STING pathway in trophoblast.

Antioxidant Capacity of Free and Bound Phenolics from Olive Leaves: In Vitro and In Vivo Responses

Olive leaves are rich in phenolic compounds. This study explored the chemical profiles and contents of free phenolics (FPs) and bound phenolics (BPs) in olive leaves, and further investigated and compared the antioxidant properties of FPs and BPs using chemical assays, cellular antioxidant evaluation systems, and in vivo mouse models. The results showed that FPs and BPs have different phenolic profiles; 24 free and 14 bound phenolics were identified in FPs and BPs, respectively. Higher levels of phenolic acid (i.e., sinapinic acid, 4-coumaric acid, ferulic acid, and caffeic acid) and hydroxytyrosol were detected in the BPs, while flavonoids, triterpenoid acids, and iridoids were more concentrated in the free form. FPs showed a significantly higher total flavonoid content (TFC), total phenolic content (TPC), and chemical antioxidant properties than those of BPs (p < 0.05). Within the range of doses (20-250 μg/mL), both FPs and BPs protected HepG2 cells from H2O2-induced oxidative stress injury, and there was no significant difference in cellular antioxidant activity between FPs and BPs. The in vivo experiments suggested that FP and BP treatment inhibited malondialdehyde (MDA) levels in a D-galactose-induced oxidation model in mice, and significantly increased antioxidant enzyme activity of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT), and the total antioxidant capacity (T-AOC). Mechanistically, FPs and BPs exert their antioxidant activity in distinct ways; FPs ameliorated D-galactose-induced oxidative stress injury partly via the activation of nuclear factor erythroid-2-related factor 2 (Nrf2) signaling pathway, while the BP mechanisms need further study.