Copper and iron transport across the placenta: regulation and interactions

Toxic and essential elements in primary teeth and maternal blood during pregnancy: The Norwegian Mother, Father and Child Cohort Study (MoBa) and the MoBaTooth Biobank

BACKGROUND

Maternal exposure to toxic and essential elements can be transferred to the fetus. Deciduous tooth dentine, formed prenatally, serves as a potential biomarker for fetal exposure.

OBJECTIVE

To investigate the relationship between maternal blood Pb, Mn, Cu, Mo and Zn element concentrations and the corresponding child tooth dentine levels in mid pregnancy. A secondary objective explores the predictive value of maternal blood element concentrations for child dentine element levels for the same metals.

METHODS

Early-life element concentrations were measured in maternal whole blood from the 2nd trimester and in child tooth dentine from 94 child-mother dyads enrolled in the Norwegian Mother, Father and Child Cohort Study (MoBa), The Norwegian Environmental Biobank (NEB) and the MoBaTooth biobank. The relationship between lead (Pb), manganese (Mn), copper (Cu), molybdenum (Mo) and zinc (Zn) in maternal blood and child dentine was examined using correlations and Receiver Operating Characteristic (ROC) curves.

RESULTS

Maternal blood Pb concentration and child dentine Pb in 2nd trimester-average correlated strongly for both girls and boys (r = 0.58, p < 0.001 and r = 0.51, p < 0.001) and was able to predict child dentine Pb. Cu correlated negatively between mothers and boys (r = -0.35, p < 0.001), and with borderline significance for girls (r = -0.17, p = 0.058). For Mn, Mo and Zn the associations between maternal blood and child dentine were less clear and differed by child sex.

CONCLUSION

Our analysis confirmed a strong association between maternal blood Pb concentration and child tooth dentine Pb. These findings offer a promising biomarker of early life exposure and may help to identify consequences of maternal exposure during pregnancy.

Prenatal Exposure to Metals Is Associated with Placental Decelerated Epigenetic Gestational Age in a Sex-Dependent Manner in Infants Born Extremely Preterm

Prenatal exposure to metals can influence fetal programming via DNA methylation and has been linked to adverse birth outcomes and long-term consequences. Epigenetic clocks estimate the biological age of a given tissue based on DNA methylation and are potential health biomarkers. This study leveraged the Extremely Low Gestational Age Newborn (ELGAN) study (n = 265) to evaluate associations between umbilical cord tissue concentrations of 11 metals as single exposures as well as mixtures in relation to (1) placental epigenetic gestational age acceleration (eGAA) and the (2) methylation status of the Robust Placental Clock (RPC) CpGs. Linear mixed effect regression models were stratified by infant sex. Both copper (Cu) and manganese (Mn) were significantly associated with a decelerated placental eGA of -0.98 (95% confidence interval (CI): -1.89, -0.07) and -0.90 weeks (95% CI: -1.78, -0.01), respectively, in male infants. Cu and Mn levels were also associated with methylation at RPC CpGs within genes related to processes including energy homeostasis and inflammatory response in placenta. Overall, these findings suggest that prenatal exposures to Cu and Mn impact placental eGAA in a sex-dependent manner in ELGANs, and future work could examine eGAA as a potential mechanism mediating in utero metal exposures and later life consequences.

Gestational diabetes mellitus enhances cobalt placental transfer efficiency between mother and infant

Background: The fetal stage is pivotal for growth and development, making it susceptible to the adverse effects of prenatal metal(loid)s exposure. This study evaluated the influence of gestational diabetes mellitus (GDM) on the placental transfer efficiency (PTE) of metal(loid)s and thus assessed the associated risks of prenatal metal(loid)s exposure.

Materials and method: Designed as a case-control study, it incorporated 114 pregnant participants: 65 without complications and 49 diagnosed with GDM. We utilized inductively coupled plasma mass spectrometry to quantify seven metal(loid)s - manganese (Mn), cobalt (Co), nickel (Ni), copper (Cu), gallium (Ga), arsenic (As), and cadmium (Cd) - in both maternal venous blood and umbilical cord blood.

Result: We compared metal(loid)s concentrations and their PTE in the maternal and cord blood between the two groups. Notably, Cu, Ga, As, and Co levels in the umbilical cord blood of the GDM group (657.9 ± 167.2 μg/L, 1.23 ± 0.34 μg/L, 5.19 ± 2.58 μg/L, 1.09 ± 2.03 μg/L) surpassed those of the control group, with PTE of Co showing a marked increase in GDM group (568.8 ± 150.4 μg/L, 1.05 ± 0.31 μg/L, 4.09 ± 2.54 μg/L, 0.47 ± 0.91 μg/L), with PTE of Co showing a marked increase in GDM group (p < 0.05). The PTE of Ni exhibited a reduction in the GDM group relative to the control group, yet this decrease did not reach statistical significance.

Conclusion: This study indicates that GDM can influence the placental transfer efficiency of certain metal(loid)s, leading to higher concentrations of Co, Cu, Ga, and As in the umbilical cord blood of the GDM group. The marked increase in the PTE of Co suggests a potential link to placental abnormal angiogenesis due to GDM.

Preeclampsia and transport of ions and small molecules: A literature review

Preeclampsia (PE) is a prevalent obstetric complication affecting approximately 3-5% of pregnancies worldwide and is a major cause of maternal and perinatal morbidity and mortality. Preeclampsia is considered a disease of the endothelial system that can progress to eclampsia, characterized by seizures. Early diagnosis and appropriate management are crucial to improving maternal and fetal outcomes, as preeclampsia can lead to severe complications such as placental abruption, fetal growth restriction, and stroke. The pathophysiology of PE is complex, involving a combination of genetic, acquired, and immunological factors. A central feature of the condition is inadequate placentation and impaired uteroplacental perfusion, leading to local hypoxia, endothelial dysfunction, vasoconstriction, and immunological dysregulation. Recent evidence suggests that dysregulation of ion transporters may play a significant role in the adaptation of uterine circulation during placentation. These transporters are essential for maintaining maternal-fetal homeostasis, influencing processes such as nutrient exchange, hormone synthesis, trophoblast cell migration, and the function of smooth muscle cells in blood vessels. In preeclampsia, adverse conditions like hypoxia and oxidative stress result in the downregulation of ion, solute, and water transporters, impairing their function. This review focuses on membrane transporters involved in PE, discussing functional alterations and their physiological implications. The goal of this investigation is to enhance understanding of how dysregulation of ion and small molecule transporters contributes to the development and progression of preeclampsia, underscoring the importance of exploring these signaling pathways for potential therapeutic interventions.

Role of mineral nutrients other than iron in pregnancy: under recognized opportunities to improve maternal/fetal outcomes: a literature review

BACKGROUND

Anemia during pregnancy is an important global health concern, affecting 40% of women worldwide, and iron deficiency shares a significant proportion of the burden. From conception to birth, pregnancy is a period when women undergo metabolic and physiological changes. The nutritional needs are higher during pregnancy; thus, adequate nutrition is essential to maintain fetal growth and development. However, adverse effects due to deficiency in nutrition during pregnancy can result in maternal, fetal and neonatal complications. Despite the multifactorial etiology of anemia, iron deficiency is assumed as the primary cause of anemia during pregnancy and hence, mitigation strategy pivots around it for anemia management. Therefore, excluding other contributors, a single-micronutrient approach with iron supplements remains a myopic approach and this can exacerbate iron deficiency anemia. Micronutrient deficiencies are of particular concern as they may pose a silent threat to the survival and well-being of reproductive-age women and their infants.

AIM

Micronutrients, especially trace minerals, play a myriad of roles in pregnancy, and the lack of each one causes adverse complications to both the mother and the fetus. In this review paper, we attempt to piece together available information regarding the adverse effects of abnormal trace mineral levels along with iron deficiency on the mother and the fetus.

METHOD

A non-systematic literature search in PubMed, Google Scholar, and the Cochrane databases, for publications on minerals and vitamins during pregnancy and the possible influence of supplements on pregnancy outcomes.

CONCLUSION

Micronutrient deficiency exacerbates the pregnancy-induced anemia and other adverse birth outcomes. Micronutrient supplementation during pregnancy can combat anemia as well as reduce a number of adverse pregnancy outcomes in a comprehensive manner.

Exposure to manganese during sertoli cell formation and proliferation disturbs early testicular development in rats

Manganese (Mn) is a metal and important micronutrient. However, exposure to supraphysiological levels of Mn, which occur through fungicides, atmospheric emissions, drainages, and spills, has been related to health risks, including morphometric changes in the male reproductive organs and impairment on gametogenesis and sperm quality, impacting the fertile ability of adult animals. Despite the relevance of the fetal/perinatal period for toxicological studies on Mn, previous data only deal with the physical and neurological development of the offspring, without mentioning their reproductive development. The present study investigated whether exposure to Mn during fetal/perinatal phase, specifically during the period of formation and proliferation of Sertoli cells, impairs the reproductive development of male offspring in early postnatal life. Therefore, pregnant Wistar rats were randomly distributed into 3 experimental groups: Ctl (received saline solution), Mn-9 (received 9 mg/kg of MnCl2), and Mn-90 (received 90 mg/kg of MnCl2). The female rats received the experimental treatment by gavage from gestational day 13 to lactational day 15, i.e., postnatal day (PND) 15 of the pups. Oxidative damage to the genetic material of germ and Sertoli cells, together with a decrease in connexin 43 immunolabeling were observed in the testis of male pups evaluated at PND 15. In addition, an increase in the seminiferous tubules presenting slight epithelium vacuolization and cells with eosinophilic cytoplasm were observed, without apparent epididymal changes. In conclusion, it was demonstrated that Mn perturbed the initial testicular development by altering Sertoli cell integrity through oxidative insult, which may compromise the spermatogenesis in the long-term.

Expression of placental glycans and its role in regulating peripheral blood NK cells during preeclampsia: a perspective

Preeclampsia is a pregnancy-related multisystem disorder characterized by altered trophoblast invasion, oxidative stress, exacerbation of systemic inflammatory response, and endothelial damage. The pathogenesis includes hypertension and mild-to-severe microangiopathy in the kidney, liver, placenta, and brain. The main mechanisms involved in its pathogenesis have been proposed to limit trophoblast invasion and increase the release of extracellular vesicles from the syncytiotrophoblast into the maternal circulation, exacerbating the systemic inflammatory response. The placenta expresses glycans as part of its development and maternal immune tolerance during gestation. The expression profile of glycans at the maternal-fetal interface may play a fundamental role in physiological pregnancy changes and disorders such as preeclampsia. It is unclear whether glycans and their lectin-like receptors are involved in the mechanisms of maternal-fetal recognition by immune cells during pregnancy homeostasis. The expression profile of glycans appears to be altered in hypertensive disorders of pregnancy, which could lead to alterations in the placental microenvironment and vascular endothelium in pregnancy conditions such as preeclampsia. Glycans with immunomodulatory properties at the maternal-fetal interface are altered in early-onset severe preeclampsia, implying that innate immune system components, such as NK cells, exacerbate the systemic inflammatory response observed in preeclampsia. In this article, we discuss the evidence for the role of glycans in gestational physiology and the perspective of glycobiology on the pathophysiology of hypertensive disorders in gestation.

Maternal Mineral Nutrition Regulates Fetal Genomic Programming in Cattle: A Review

Maternal mineral nutrition during the critical phases of fetal development may leave lifetime impacts on the productivity of an individual. Most research within the developmental origins of the health and disease (DOHaD) field is focused on the role of macronutrients in the genome function and programming of the developing fetus. On the other hand, there is a paucity of knowledge about the role of micronutrients and, specifically, minerals in regulating the epigenome of livestock species, especially cattle. Therefore, this review will address the effects of the maternal dietary mineral supply on the fetal developmental programming from the embryonic to the postnatal phases in cattle. To this end, we will draw a parallel between findings from our cattle model research with data from model animals, cell lines, and other livestock species. The coordinated role and function of different mineral elements in feto-maternal genomic regulation underlies the establishment of pregnancy and organogenesis and, ultimately, affects the development and functioning of metabolically important tissues, such as the fetal liver, skeletal muscle, and, importantly, the placenta. Through this review, we will delineate the key regulatory pathways involved in fetal programming based on the dietary maternal mineral supply and its crosstalk with epigenomic regulation in cattle.

Exposure to essential and non-essential trace elements and risks of congenital heart defects: A narrative review

Congenital heart defects (CHDs) are congenital abnormalities involving the gross structures of the heart and large blood vessels. Environmental factors, genetic factors and their interactions may contribute to the pathogenesis of CHDs. Generally, trace elements can be classified into essential trace elements and non-essential trace elements. Essential trace elements such as copper (Cu), zinc (Zn), iron (Fe), selenium (Se), and manganese (Mn) play important roles in human biological functions such as metabolic function, oxidative stress regulation, and embryonic development. Non-essential trace elements such as cadmium (Cd), arsenic (As), lead (Pb), nickle (Ni), barium (Ba), chromium (Cr) and mercury (Hg) are harmful to health even at low concentrations. Recent studies have revealed the potential involvement of these trace elements in the pathogenesis of CHDs. In this review, we summarized current studies exploring exposure to essential and non-essential trace elements and risks of CHDs, in order to provide further insights for the pathogenesis and prevention of CHDs.

Air Pollution-Related Neurotoxicity Across the Life Span

Air pollution is a complex mixture of gases and particulate matter, with adsorbed organic and inorganic contaminants, to which exposure is lifelong. Epidemiological studies increasingly associate air pollution with multiple neurodevelopmental disorders and neurodegenerative diseases, findings supported by experimental animal models. This breadth of neurotoxicity across these central nervous system diseases and disorders likely reflects shared vulnerability of their inflammatory and oxidative stress-based mechanisms and a corresponding ability to produce brain metal dyshomeo-stasis. Future research to define the responsible contaminants of air pollution underlying this neurotoxicity is critical to understanding mechanisms of these diseases and disorders and protecting public health.

Comparison of trace element concentrations in paired formalin-fixed paraffin-embedded and frozen human placentae

INTRODUCTION

There is increasing interest in measuring metals concentrations in human placentas to better understand physiology, disease, and toxic and diagnostic exposures. For these purposes, formalin-fixed paraffin embedded (FFPE) tissues obtained at clinical pathology examination represent a valuable potential store of well-characterized tissues for analysis. However, the limited data that exist comparing metal concentrations in FFPE tissue to recently collected frozen tissues paints a confusing picture, and there is no published data directly comparing frozen and FFPE placental villus tissues.

METHODS

Paired samples of fresh frozen and FFPE tissue from 22 rapidly processed human singleton placentae were weighed and digested using standard clean laboratory procedures and subsequently analyzed for a suite of 13 metals using a PerkinElmer DRC II ICP-MS. The analytical results were compared using either a paired t-test or a sign test depending on data normality.

RESULTS

Concentrations of metals (aluminum (Al), arsenic (As), barium (Ba), cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), gadolinium (Gd), mercury (Hg), manganese (Mn), lead (Pb), strontium (Sr), and zinc (Zn)) measured in both types of tissue preparations (frozen and FFPE) displayed a consistent range with other studies and did not display significantly different values from each of the paired specimens for any of the 13 specific metals analyzed.

DISCUSSION

Within placentae, metals concentrations of measured trace, toxic and diagnostic elements (Al, As, Ba, Cd, Cr, Cu, Fe, Gd, Hg, Mn, Pb, Sr, and Zn) are consistent between FFPE and fresh placental villus tissue, without indications of systematic element loss or bias. FFPE from archived pathology specimens may offer an important and convenient alternative for measuring trace metals in human frozen placental tissues.

Association of Zn and Cu Levels in Cord Blood and Maternal Milk with Pregnancy Outcomes among the Slovenian Population

Trace elements, including zinc (Zn) and copper (Cu), are known to play important roles in human health. The present study aimed to assess the levels of Zn and Cu in cord blood and maternal milk and to analyze their association with maternal and infant characteristics and pregnancy outcomes in a Slovenian study population of mothers and their neonates recruited within the PHIME prospective cohort study. The study included 324 mothers, but the data on Zn and Cu levels in both cord blood and maternal milk was available for 243 mothers. Questionnaires were used to assess the socio-demographic and health status of the mothers, their lifestyle habits (including detailed nutritional habits), and their residential and occupational histories. Inductively Coupled Plasma Mass Spectrometry (ICP-MS) was used to measure Zn and Cu levels in cord blood and maternal milk. Low Zn levels in cord blood were associated with lower gestational age and birth weight and were correlated with an increased probability of the birth of small for gestational age (SGA) infants. Maternal smoking influenced the Cu levels in both cord blood and maternal milk. Cord blood Cu levels were higher and Cu levels in maternal milk were lower in smoking compared to non-smoking mothers. Most importantly, a decreased Zn/Cu ratio in cord blood was associated with lower gestational age and lower birth weight. This indicates the overall positive effects of Zn and negative effects of Cu on pregnancy outcomes.

Fetoplacental oxygen homeostasis in pregnancies with maternal diabetes mellitus and obesity

Despite improvements in clinical management, pregnancies complicated by pre-existing diabetes mellitus, gestational diabetes mellitus or obesity carry substantial risks for parent and offspring. Some of the endocrine and metabolic changes in parent and fetus in diabetes mellitus and obesity lead to fetal oxygen deficit, mostly due to insulin-induced accelerated fetal metabolism. The human fetus deals with reduced oxygenation through a wide range of adaptive responses that act at various levels in the placenta as well as the fetus. These responses ensure adequate oxygen delivery to the fetus, increase the oxygen transport capacity of fetal blood and redistribute oxygen-rich blood to vital organs such as the brain and heart. The liver has a central role in adapting to reduced oxygenation by increasing its oxygen extraction and stimulating erythropoietin synthesis to increase haematocrit. The type of adaptive response depends on the onset and duration of hypoxia and the severity of the metabolic disturbance. In pregnancies characterized by diabetes mellitus or obesity, these adaptive systems come under additional strain owing to the increased maternal supply of glucose and resultant fetal hyperinsulinaemia, both of which stimulate oxidative metabolism. In the rare situation that the adaptive responses are overwhelmed, stillbirth can ensue.

Examination of Trace Metals and Their Potential Transplacental Transfer in Pregnancy

With the ever-growing concern for human health and wellbeing, the prenatal period of development requires special attention since fetuses can be exposed to various metals through the mother. Therefore, this study explored the status of selected toxic (Pb, Cd, Ni, As, Pt, Ce, Rb, Sr, U) and essential trace metals (Mn, Co, Cu, Zn, Se) in the umbilical cord (UC) sera, maternal sera, and placental tissue samples of 92 healthy women with normal pregnancies. A further aim focuses on the potential transplacental transfer of these trace metals. Based on the obtained levels of investigated elements in clinical samples, it was observed that all of the trace metals cross the placental barrier and reach the fetus. Furthermore, statistical analysis revealed significant differences in levels of toxic Ni, As, Cd, U, Sr, Rb, and essential Mn, Cu, and Zn between all three types of analyzed clinical samples. Correlation analysis highlighted As to be an element with levels that differed significantly between all tested samples. Principal component analysis (PCA) was used to enhance these findings. PCA demonstrated that Cd, Mn, Zn, Rb, Ce, U, and Sr were the most influential trace metals in distinguishing placenta from maternal and UC serum samples. As, Co, and Cu were responsible for the clustering of maternal serum samples, and PCA demonstrated that the Pt level in UC sera was responsible for the clustering of these samples. Overall, the findings of this study could contribute to a better understanding of transplacental transfer of these trace metals, and shed a light on overall levels of metal exposure in the population of healthy pregnant women and their fetuses.

Prenatal exposure to metal mixtures and newborn neurobehavior in the Rhode Island Child Health Study

BACKGROUND

Prenatal exposure to metals can affect the developing fetus and negatively impact neurobehavior. The associations between individual metals and neurodevelopment have been examined, but little work has explored the potentially detrimental neurodevelopmental outcomes associated with the combined impact of coexisting metals. The objective of this study is to evaluate prenatal metal exposure mixtures in the placenta to elucidate the link between their combined effects on newborn neurobehavior.

METHOD

This study included 192 infants with available placental metal and NICU Network Neurobehavioral Scale data at 24 hours-72 hours age. Eight essential and nonessential metals (cadmium, cobalt, copper, iron, manganese, molybdenum, selenium, zinc) detected in more than 80% of samples were tested for associations with atypical neurobehavior indicated by NICU Network Neurobehavioral Scale using logistic regression and in a quantile g-computation analysis to evaluate the joint association between placental metal mixture and neurobehavioral profiles.

RESULTS

Individually, a doubling of placental cadmium concentrations was associated with an increased likelihood of being in the atypical neurobehavioral profile (OR = 2.39; 95% CI = 1.05 to 5.71). In the mixture analysis, joint effects of a quartile increase in exposure to all metals was associated with 3-fold increased odds of newborns being assigned to the atypical profile (OR = 3.23; 95% CI = 0.92 to 11.36), with cadmium having the largest weight in the mixture effect.

CONCLUSIONS

Prenatal exposure to relatively low levels of a mixture of placental metals was associated with adverse newborn neurobehavior. Examining prenatal metal exposures as a mixture is important for understanding the harmful effects of concomitant exposures in the vulnerable populations.

Selected Metal Concentration in Maternal and Cord Blood

Essential and non-essential elements deficiencies may lead to various birth complications. The aim of this paper was to determine calcium (Ca), copper (Cu), iron (Fe), potassium (K), magnesium (Mg), sodium (Na), phosphorus (P), lead (Pb), strontium (Sr), and zinc (Zn) concentrations in maternal blood and cord blood. Whole blood and cord blood samples collected from pregnant women (n = 136) were analyzed for the concentration of the elements by spectrophotometric atomic absorption in inductively coupled argon plasma (ICP-OES). The results showed that Ca, Pb, and Sr concentrations were similar in maternal and cord blood, while Fe and K levels were higher in cord blood than in maternal blood. The cord blood Cu, Na, and Zn concentrations were lower than those in maternal blood, suggesting transplacental transfer of these elements were limited. Moreover, checking the influence of studied elements on the anthropometric parameters of the newborns, we found that the highest number of associations was between Cu in cord blood. Due to the fact that the pregnant women were healthy, and the newborns were without any disorders, we suggest that the values obtained in our study are normal values of studied elements in whole blood and cord blood in patients from Poland.

Prevalence of Anemia and Associated Factors Among Term Newborns in Nekemte Specialized Hospital, Western Ethiopia

Background

Anemia is a global public health problem that affects approximately one-third of the global population. Infants and children are the ones to develop both short-term and long-term devastating complications from anemia. Although anemia is a very big public health concern, newborns, especially in developing countries, are usually overlooked and undiagnosed.

Purpose

The aim of this study was to assess the prevalence of anemia and associated factors among term newborns in Nekemte Specialized Hospital, Western Ethiopia.

Methods

A facility-based cross-sectional study involving 278 newborns was conducted from October to November, 2020 with an interview-based questionnaire that included maternal socio-demographic and obstetrics characteristics, newborn’s weight and sex. The data were analyzed with SPSS version 20. The prevalence of newborn anemia was shown in percentage and as a pie-chart. Bivariate analysis and binary logistic regression were used to identify the predictors of anemia in the term newborn.

Results

The overall prevalence of newborn anemia in the hospital was 29.1%. Maternal anemia (AOR: 3.95, 95% C.I.: 1.97–7.92), delivery by cesarean section (AOR: 4.17, 95% C.I.: 1.89–9.20), vaginal bleeding during pregnancy (AOR: 5.43, 95% C.I.: 1.60–18.39), and maternal failure to take iron-folate supplements during pregnancy (AOR: 2.17, 95% C.I.:1.07–4.41) were factors associated with newborn anemia.

Conclusion

Anemia among newborns in the hospital was a moderate public health problem. Policy makers should consider maternal health education and appropriate health interventions to reduce the problem. In addition, further longitudinal studies are needed to identify specific causes of newborn anemia in order to prevent the possible complications.

Dietary Iron Intake in Excess of Requirements Impairs Intestinal Copper Absorption in Sprague Dawley Rat Dams, Causing Copper Deficiency in Suckling Pups

Physiologically relevant iron-copper interactions have been frequently documented. For example, excess enteral iron inhibits copper absorption in laboratory rodents and humans. Whether this also occurs during pregnancy and lactation, when iron supplementation is frequently recommended, is, however, unknown. Here, the hypothesis that high dietary iron will perturb copper homeostasis in pregnant and lactating dams and their pups was tested. We utilized a rat model of iron-deficiency/iron supplementation during pregnancy and lactation to assess this possibility. Rat dams were fed low-iron diets early in pregnancy, and then switched to one of 5 diets with normal (1×) to high iron (20×) until pups were 14 days old. Subsequently, copper and iron homeostasis, and intestinal copper absorption (by oral, intragastric gavage with ⁶⁴Cu), were assessed. Copper depletion/deficiency occurred in the dams and pups as dietary iron increased, as evidenced by decrements in plasma ceruloplasmin (Cp) and superoxide dismutase 1 (SOD1) activity, depletion of hepatic copper, and liver iron loading. Intestinal copper transport and tissue ⁶⁴Cu accumulation were lower in dams consuming excess iron, and tissue ⁶⁴Cu was also low in suckling pups. In some cases, physiological disturbances were noted when dietary iron was only ~3-fold in excess, while for others, effects were observed when dietary iron was 10–20-fold in excess. Excess enteral iron thus antagonizes the absorption of dietary copper, causing copper depletion in dams and their suckling pups. Low milk copper is a likely explanation for copper depletion in the pups, but experimental proof of this awaits future experimentation.

Evaluation of Fetal Exposures to Metals and Metalloids through Meconium Analyses: A Review

This paper surveys the existing scientific literature on metals concentrations in meconium. We examine some 32 papers that analyzed meconium for aluminum, arsenic, barium, calcium, chromium, copper, iron, lithium, magnesium, manganese, zinc, lead, mercury, manganese, molybdenum, nickel, phosphorus, lead, antimony, selenium, tin, vanadium, and zinc. Because of the lack of detail in the statistics it is not possible to do a rigorous meta-analysis. What stands out is that almost every study had subjects with seemingly large amounts of at least one of the metals. The significance of metals in meconium is not clear beyond an indication of exposure although some studies have correlated metals in meconium to a number of adverse outcomes. A number of outstanding questions have been identified that, if resolved, would greatly increase the utility of meconium analysis for assessment of long-term gestational metals exposures. Among these are questions of the developmental and long-term significance of metals detected in meconium, the kinetics and interactions among metals in maternal and fetal compartments and questions on best methods for meconium analyses.

From Maternal Diet to Neurodevelopmental Disorders: A Story of Neuroinflammation

Providing the appropriate quantity and quality of food needed for both the mother's well-being and the healthy development of the offspring is crucial during pregnancy. However, the macro- and micronutrient intake also impacts the body's regulatory supersystems of the mother, such as the immune, endocrine, and nervous systems, which ultimately influence the overall development of the offspring. Of particular importance is the association between unhealthy maternal diet and neurodevelopmental disorders in the offspring. Epidemiological studies have linked neurodevelopmental disorders like autism spectrum disorders, attention-deficit-hyperactivity disorder, and schizophrenia, to maternal immune activation (MIA) during gestation. While the deleterious consequences of diet-induced MIA on offspring neurodevelopment are increasingly revealed, neuroinflammation is emerging as a key underlying mechanism. In this review, we compile the evidence available on how the mother and offspring are both impacted by maternal dietary imbalance. We specifically explore the various inflammatory and anti-inflammatory effects of dietary components and discuss how changes in inflammatory status can prime the offspring brain development toward neurodevelopmental disorders. Lastly, we discuss research evidence on the mechanisms that sustain the relationship between maternal dietary imbalance and offspring brain development, involving altered neuroinflammatory status in the offspring, as well as genetic to cellular programming notably of microglia, and the evidence that the gut microbiome may act as a key mediator.

Oral exposure of pregnant rats to copper nanoparticles caused nutritional imbalance and liver dysfunction in fetus

Copper nanoparticles (Cu NPs) are increasingly used as an animal feed additive in China. In previous studies, it was determined that Cu NPs can penetrate the placental barrier, however, its toxic effects on the fetus have not yet been elucidated. Therefore, in this study, we investigated the potential fetal toxic effects of Cu NPs. Cu NPs were orally administered to pregnant Sprague-Dawley rats from gestation days (GDs) 3-18 at a dose of 60, 120, and 180 mg/kg/day. Cesarean sections were conducted on GD 19. During fetal examination, no toxicities were observed regarding general clinical signs, however, Cu NPs significantly decreased fetal body weight, body length, and liver weights. Cu ions and Cu MPs exhibited similar effects on the fetal development. Cu NPs increased the liver concentration of Cu, and decreased protein levels and Fe in fetuses. Cu NPs also increased oxidative stress and inflammation in the fetus after pregnant rats were exposed to high doses of Cu NPs. Oral exposure to Cu NPs during pregnancy increased Cu concentrations in the fetus, which not only affected fetal development, but also significantly induced oxidative stress and inflammatory responses in fetal liver. Taken together, these findings are valuable to evaluate fetal risk assessment after oral exposure of Cu NPs during pregnancy. Additional comprehensive toxicity studies are deemed necessary to clarify the underlying mechanisms involved.

Air Pollution-Related Brain Metal Dyshomeostasis as a Potential Risk Factor for Neurodevelopmental Disorders and Neurodegenerative Diseases

Increasing evidence links air pollution (AP) exposure to effects on the central nervous system structure and function. Particulate matter AP, especially the ultrafine (nanoparticle) components, can carry numerous metal and trace element contaminants that can reach the brain in utero and after birth. Excess brain exposure to either essential or non-essential elements can result in brain dyshomeostasis, which has been implicated in both neurodevelopmental disorders (NDDs; autism spectrum disorder, schizophrenia, and attention deficit hyperactivity disorder) and neurodegenerative diseases (NDGDs; Alzheimer’s disease, Parkinson’s disease, multiple sclerosis, and amyotrophic lateral sclerosis). This review summarizes the current understanding of the extent to which the inhalational or intranasal instillation of metals reproduces in vivo the shared features of NDDs and NDGDs, including enlarged lateral ventricles, alterations in myelination, glutamatergic dysfunction, neuronal cell death, inflammation, microglial activation, oxidative stress, mitochondrial dysfunction, altered social behaviors, cognitive dysfunction, and impulsivity. Although evidence is limited to date, neuronal cell death, oxidative stress, and mitochondrial dysfunction are reproduced by numerous metals. Understanding the specific contribution of metals/trace elements to this neurotoxicity can guide the development of more realistic animal exposure models of human AP exposure and consequently lead to a more meaningful approach to mechanistic studies, potential intervention strategies, and regulatory requirements.

The Role of Fe, Zn, and Cu in Pregnancy

Iron (Fe), copper (Cu), and zinc (Zn) are microelements essential for the proper functioning of living organisms. These elements participatein many processes, including cellular metabolism and antioxidant and anti-inflammatory defenses, and also influence enzyme activity, regulate gene expression, and take part in protein synthesis. Fe, Cu, and Zn have a significant impact on the health of pregnant women and in the development of the fetus, as well as on the health of the newborn. A proper concentration of these elements in the body of women during pregnancy reduces the risk of complications such as anemia, induced hypertension, low birth weight, preeclampsia, and postnatal complications. The interactions between Fe, Cu, and Zn influence their availability due to their similar physicochemical properties. This most often occurs during intestinal absorption, where metal ions compete for binding sites with transport compounds. Additionally, the relationships between these ions have a great influence on the course of reactions in the tissues, as well as on their excretion, which can be stimulated or delayed. This review aims to summarize reports on the influence of Fe, Cu, and Zn on the course of single and multiple pregnancies, and to discuss the interdependencies and mechanisms occurring between Fe, Cu, and Zn.

Maternal, placental and cordonal metallomic profiles in gestational diabetes mellitus

76 pregnant women, among them 38 affected by gestational diabetes mellitus (GDM) and 38 control subjects, were recruited at the University Hospital of Padua (Italy). Placenta samples, maternal whole blood and umbilical cord whole blood were collected after delivery and analysed via ICP-MS to determine the metallome, i.e. the whole elemental content. Results were statistically evaluated to evidence the correlation between the elemental concentrations in all samples and the presence of the disease. The results obtained in whole cord blood showed that many elements were correlated with GDM: Ca, Cu, Na, and Zn were present in higher concentration in GDM cord blood than in control samples, whereas Fe, K, Mn, P, Rb, S and Si showed an opposite trend. It was also highlighted that the cord blood from GDM patients exhibited an elemental composition more similar to that of the mother blood compared with the cord blood from control subjects. These results, in part interpreted in the light of the literature, open the possibility to use cord blood as a GDM marker, thus helping to delineate more accurate nutritional guidelines for pregnant women and to explain the biochemical processes occurring in the fetus and placenta during GDM.

In Utero Exposure to Aluminium and Other Neurotoxic Elements in Urban Coastal South African Women at Delivery: An Emerging Concern

Aluminium (Al) is a non-essential neurotoxicant and there is limited information regarding exposure to Al in utero. This study sought to evaluate the in utero exposure to Al in urban South African women, its effects on birth outcomes and possible synergistic effects between Al, essential and neurotoxic elements such as lead (Pb), mercury (Hg) and arsenic (As), as well as a a potential sex-dependent response to these elements in neonates. This study has found elevated levels of Al in urban women at delivery. The Spearman’s rank correlation coefficients (p-value) of the association between maternal serum Al and birth outcomes (gestational age and parity), and between maternal serum Al and Cu, Zn and Se, were statistically significant. However, in the general and the stratified models, no association was found between any of the birth outcomes and maternal serum Al. The association between maternal serum Al and neurotoxic elements at delivery showed a significant positive correlation for Pb only (rho = 0.361; p < 0.001) which was found to be sex-dependent in neonates (males, rho = 0.285; p < 0.004 and females, rho = 0.444, p < 0.001). Our preliminary findings indicate that in utero exposure to Al is an emerging concern requiring further research and directives from public health authorities.

Copper associates with differential methylation in placentae from two US birth cohorts

Copper is an essential trace nutrient and an enzymatic cofactor necessary for diverse physiological and biological processes. Copper metabolism is uniquely controlled in the placenta and changes to copper metabolism have been linked with adverse birth outcomes. We investigated associations between patterns of DNA methylation (DNAm; measured at >485 k CpG sites) and copper concentration measured from placentae in two independent mother-infant cohorts: the New Hampshire Birth Cohort Study (NHBCS, n = 306) and the Rhode Island Child Health Study (RICHS, n = 141). We identified nine copper-associated differentially methylated regions (DMRs; adjusted P < 0.05) and 15 suggestive CpGs (raw P < 1e-5). One of the most robust variably methylated CpGs associated with the expression of the antioxidant, GSTP1. Our most robust DMR negatively associates with the expression of the zinc-finger gene, ZNF197 (FDR = 4.5e-11). Genes co-expressed with ZNF197, a transcription factor, are enriched for genes that associate with birth weight in RICHS (OR = 2.9, P = 2.6e-6, N = 194), genes that are near a ZNF197 consensus binding motif (OR = 1.34, P = 0.01, N = 194), and for those classified in GO biological processes growth hormone secretion (P = 3.4e-4), multicellular organism growth (P = 3.8e-4), and molecular functions related to lipid biosynthesis (P = 1.9e-4). Further, putative transcriptional targets for ZNF197 include genes involved in copper metabolism and placentation. Our results suggest that copper metabolism is tied to DNAm in the placenta and that copper-associated patterns in DNAm may mediate normal placentation and foetal development.

The concentration of selected elements in the placenta according to selected sociodemographic factors and their effect on birth mass and birth length of newborns

BACKGROUND AND AIMS

The placenta is a remarkable organ which provides critical transport functions between the maternal and fetal circulations during pregnancy. The demand for mineral components increases during the gestational period, therefore, an appropriate intake of minerals, such as calcium, phosphorus, potassium, magnesium, iron, zinc, copper, and manganese, determines the correct growth and development of a fetus. The aim of the study was to assess the concentration of selected elements in the placenta, and to assess the impact of their concentrations on the birth weight and birth length of newborns. The second aim of the study was to assess the influence of selected sociodemographic factors on the concentration of elements in the placenta.

RESULTS

The study demonstrated that the age of mothers affected the concentration of Ca and Mn in the placenta, and their habit of tobacco smoking during the gestational period was associated with higher concentrations of Ca, P, K, Mg, Fe, Cu, and Cd in the placental tissue. The results also showed that concentrations of K, Fe, Zn, and Mn in the placental tissue affected birth length. Furthermore, the association was demonstrated between a higher Cd concentration in the placenta (≥ 0.0503 μg/g) and the birth anthropometric parameters of neonates.

CONCLUSIONS

Smoking during pregnancy and environment pollution are the factors that affects the concentration of elements in the placenta and contributes to their high accumulation in the placenta. Smoking during pregnancy causes an increased concentration of cadmium in the placenta which has negative health effects for the newborn. Women living in a big city or village had a higher concentration of cadmium in their placentas compared to women living in smaller cities. The significant influence of some elements (K, Fe, Zn, Cu and Cd) on the newborn's birth parameters was also demonstrated. The results of our research indicate the importance of the mother's lifestyle in providing the placenta with elements, which affects the growth of the fetus.

The Combined Effects of Cr(III) Supplementation and Iron Deficiency on the Copper and Zinc Status in Wistar Rats

The aim of the study was to assess the combined effects of chromium(III) supplementation and iron deficiency on the copper (Cu) and zinc (Zn) status in female rats. The Cr, Fe, Cu and Zn dietary and tissular levels were measured by Atomic Absorption Spectrometry (AAS) method. The data show that chromium(III) supplementation compensated for the negative effects of Fe deficiency on the Cu content but it deepened the effect on Zn levels in the female rats. Detailed data on the status of trace elements and their interactions in healthy subjects and patients with metabolic disorders (e.g. anaemia, diabetes mellitus) are strongly required for effective nutritional and therapeutic strategies.

Can Serum Iron Concentrations in Early Healthy Pregnancy Be Risk Marker of Pregnancy-Induced Hypertension?

The aim of this study was to assess the relationship between serum iron concentrations in early healthy pregnancy and the risk of pregnancy-induced hypertension. The data comes from our prospective cohort study in which we recruited healthy women in week 10–14 of single pregnancy. We examined a study group (n = 121) consisting of women subsequently developing pregnancy-induced hypertension and a control group (n = 363) of matched women remaining normotensive. We measured iron concentrations in the serum collected in 10–14 gestational week, using the ICP-MS technique (mass spectrometry with inductively coupled plasma). The odds ratios of the disease (95% confidence intervals) for iron concentrations were assessed in multivariate logistic regression. We found that the mean microelement concentration was lower in the case group compared to normotensive controls (p = 0.011). Women in the lowest quartile of iron (≤801.20 µg/L) had a 2.19-fold increase in pregnancy-induced hypertension risk compared with women in the highest quartile (>1211.75 µg/L) (odds ratio (OR) = 2.19; 95% CI: 1.24–3.88; p = 0.007). This result was sustained after adjusted for all the accepted confounders. Women in the higher Q₂ quartile (801.20–982.33 µg/L) had a 17% lower risk, compared with those in the highest quartile (OR = 0.83; 95% CI: 0.65–2.32; p = 0.519).

The Concentration of Micronutrients and Heavy Metals in Maternal Serum, Placenta, and Cord Blood: A Cross-Sectional Study in Preterm Birth

Background

Preterm birth is still a global burden particularly in Indonesia. The suboptimal concentration of certain micronutrients and heavy metals is hypothesized to play a role in the mechanism of preterm birth.

Objective

This study aimed to analyze the micronutrients and heavy metals concentrations between subjects with term and preterm birth.

Design

A cross-sectional study was conducted during January–June 2017 in Cipto Mangunkusumo Hospital and Budi Kemuliaan Hospital, Jakarta, Indonesia. Subjects were divided into term and preterm birth groups. The measured outcomes were maternal serum, placental, and blood cord concentration of zinc, copper, iron, selenium, manganese, mercury, lead, AtRA, and 25(OH)D.

Results

A total of 51 pregnant women participated in this study. Term group had higher concentration of maternal serum AtRA (0.22 ± 0.07 ng/mL versus 0.12 ± 0.03 ng/mL, p <0.001), higher placental concentration of manganese {0.99 (0.38 – 1.78) μg/g versus 0.42 ± 0.18 μg/g, p <0.001}, iron (252.16 ± 170.61 μg/g versus 78.45 ± 51.73 μg/g, p <0.001), copper {2.96 ± 1.80 μg/g versus 1.62 (0.70 – 3.88) μg/g, p 0.019}, zinc {58.34 (27.88 – 124.05) μg/g versus 28.41 (1.46 – 137.69) μg/g, p 0.011}, selenium (0.31 ± 0.31 ng/g versus 0.14 ± 0.20 ng/g, p 0.024), AtRA {21.7 ± 10.69 ng/g versus 0.7 (0.42 – 5.10) ng/g, p <0.001}, and 25(OH)D {75.84 ± 45.12 ng/g versus 18.00 (5 – 88) ng/g, p <0.001}, lower placental concentration of mercury (0.20 ± 0.17 ng/g versus 20.47 ± 41.35 ng/g, p 0.019) and lead (0.02 ± 0.01 ng/g versus 0.81 ± 1.43 ng/g, p 0.009), and higher cord blood concentration of copper {32.20 (16.30 – 69.60) μg/dL versus 20.60 (5.80 – 53.30) μg/dL, p 0.006} and AtRA (0.16 ± 0.04 versus 0.07 ± 0.01, p <0.001).

Conclusion

Preterm birth is associated with lower concentrations of micronutrients which play a role in antioxidant mechanism, as well as higher concentration of mercury and lead.

The effect of maternal iron deficiency on zinc and copper levels and on genes of zinc and copper metabolism during pregnancy in the rat

Fe deficiency is relatively common in pregnancy and has both short- and long-term consequences. However, little is known about the effect on the metabolism of other micronutrients. A total of fifty-four female rats were fed control (50 mg Fe/kg) or Fe-deficient diets (7·5 mg/kg) before and during pregnancy. Maternal liver, placenta and fetal liver were collected at day 21 of pregnancy for Cu and Zn analysis and to measure expression of the major genes of Cu and Zn metabolism. Cu levels increased in the maternal liver (P=0·002) and placenta (P=0·018) of Fe-deficient rats. Zn increased (P&lt;0·0001) and Cu decreased (P=0·006) in the fetal liver. Hepatic expression of the Cu chaperones antioxidant 1 Cu chaperone (P=0·042) and cytochrome c oxidase Cu chaperone (COX17, P=0·020) decreased in the Fe-deficient dams, while the expression of the genes of Zn metabolism was unaltered. In the placenta, Fe deficiency reduced the expression of the chaperone for superoxide dismutase 1, Cu chaperone for superoxide dismutase (P=0·030), ceruloplasmin (P=0·042) and Zn transport genes, ZRT/IRT-like protein 4 (ZIP4, P=0·047) and Zn transporter 1 (ZnT1, P=0·012). In fetal liver, Fe deficiency increased COX17 (P=0·020), ZRT/IRT-like protein 14 (P=0·036) and ZnT1 (P=0·0003) and decreased ZIP4 (P=0·004). The results demonstrate that Fe deficiency during pregnancy has opposite effects on Cu and Zn levels in the fetal liver. This may, in turn, alter metabolism of these nutrients, with consequences for development in the fetus and the neonate.

CD71+ Erythroid Suppressor Cells Promote Fetomaternal Tolerance through Arginase-2 and PDL-1

Survival of the allogeneic pregnancy depends on the maintenance of immune tolerance to paternal alloantigens at the fetomaternal interface. Multiple localized mechanisms contribute to the fetal evasion from the mother's immune rejection as the fetus is exposed to a wide range of stimulatory substances such as maternal alloantigens, microbes and amniotic fluids. In this article, we demonstrate that CD71⁺ erythroid cells are expanded at the fetomaternal interface and in the periphery during pregnancy in both humans and mice. These cells exhibit immunosuppressive properties, and their abundance is associated with a Th2 skewed immune response, as their depletion results in a proinflammatory immune response at the fetomaternal interface. In addition to their function in suppressing proinflammatory responses in vitro, maternal CD71⁺ erythroid cells inhibit an aggressive allogeneic response directed against the fetus such as reduction in TNF-α and IFN-γ production through arginase-2 activity and PD-1/programmed death ligand-1 (PDL-1) interactions. Their depletion leads to the failure of gestation due to the immunological rejection of the fetus. Similarly, fetal liver CD71⁺ erythroid cells exhibit immunosuppressive activity. Therefore, immunosuppression mediated by CD71⁺ erythroid cells on both sides (mother/fetus) is crucial for fetomaternal tolerance. Thus, our results reveal a previously unappreciated role for CD71⁺ erythroid cells in pregnancy and indicate that these cells mediate homeostatic immunosuppressive/immunoregulatory responses during pregnancy.

Trace Elements and Vitamin D in Gestational Diabetes

Gestational diabetes mellitus (GDM), one of the most common pregnancy complications, is defined as glucose intolerance with onset or first recognition during pregnancy. Its prevalence varies worldwide in dependence on characteristics of the underlying population and applied diagnostic criteria. The etiology is multifactorial and not sufficiently elucidated. Available evidence suggests that the base of pathogenesis is relatively diminished insulin secretion coupled with pregnancy-induced insulin resistance. Modifiable and non-modifiable risk factors for development have been identified. Trace elements and vitamin D could be contributed to modifiable factors for prediction the risk in a large population. Essential trace elements in pregnancy are necessary to overcome systemic oxidative, metabolic and inflammatory stress. Evidence, still inconclusive, has been accumulated about the relation between higher incidence of vitamin D failure/deficiency during pregnancy and GDM. The lower level of 25-OH vitamin D could be associated with increased risk for anemia development, also including pregnant women. This review intends to provide an overview of the possible link between both vitamin D and trace elements as risk factors for GDM development.

Trace elements, oxidative status and antioxidant capacity as biomarkers in very low birth weight infants

Reference data on trace elements, oxidative status and antioxidants in very low birth weight infants (VLBW) are limited and need to be updated for use in clinical settings. Serum and urine of 30 VLBW infants (mean weight, 1167g) at mean age of 23.8 (t0) and 37.8 (t1) days were analyzed. Cadmium (Cd), copper (Cu), iron (Fe), mercury (Hg), manganese (Mn), selenium (Se) and zinc (Zn), nitrate/nitrite (NOx), catalase (CAT), CuZnFeMn-superoxide dismutases (CuZnFeMn-SODs), total antioxidant capacity (SAC: sum of thiols, proteins, bilirubin, uric acid, β-beta-carotene, ascorbic acid, vitamin E) and total oxidative status (SOS: sum of lipo- and hydroperoxides) were determined. A higher urinary excretion of Cu and Zn was observed at t0 than at t1; while an increase in urine Cd was found at t1 respect to t0. A deficiency in serum levels of Cu and Zn was also found. A lower CAT activity, a higher total oxidants level (SOS) and a reduction of total antioxidant barriers (SAC) were observed in some infants. No Fe and Mn deficiency or Hg overload was found; also CuZnFeMn-SODs and NOx levels did not change. The findings showed that losses of trace elements and incomplete mineral body stores were more pronounced in the earlier life stage (at 23.8th day) than later on; moreover, antioxidant defenses were poor and lipo- and hydroperoxides were higher still at 5 weeks of infants' life.

Placental Origins of Chronic Disease

Epidemiological evidence links an individual's susceptibility to chronic disease in adult life to events during their intrauterine phase of development. Biologically this should not be unexpected, for organ systems are at their most plastic when progenitor cells are proliferating and differentiating. Influences operating at this time can permanently affect their structure and functional capacity, and the activity of enzyme systems and endocrine axes. It is now appreciated that such effects lay the foundations for a diverse array of diseases that become manifest many years later, often in response to secondary environmental stressors. Fetal development is underpinned by the placenta, the organ that forms the interface between the fetus and its mother. All nutrients and oxygen reaching the fetus must pass through this organ. The placenta also has major endocrine functions, orchestrating maternal adaptations to pregnancy and mobilizing resources for fetal use. In addition, it acts as a selective barrier, creating a protective milieu by minimizing exposure of the fetus to maternal hormones, such as glucocorticoids, xenobiotics, pathogens, and parasites. The placenta shows a remarkable capacity to adapt to adverse environmental cues and lessen their impact on the fetus. However, if placental function is impaired, or its capacity to adapt is exceeded, then fetal development may be compromised. Here, we explore the complex relationships between the placental phenotype and developmental programming of chronic disease in the offspring. Ensuring optimal placentation offers a new approach to the prevention of disorders such as cardiovascular disease, diabetes, and obesity, which are reaching epidemic proportions.

An immunohistochemical study of placental syncytiotrophoblasts in neonatal hemochromatosis

INTRODUCTION

Neonatal hemochromatosis (NH) is a rare neonatal disorder that results in liver cirrhosis with hemosiderin deposition in the liver and other organs, similarly to hereditary hemochromatosis. Excess iron is transferred from the mother to fetus through the placenta in NH. We examined the expression of iron metabolism-related substances in placental syncytiotrophoblasts (STB) by immunostaining to clarify how the transfer of iron through STB increases in NH.

METHODS

Immunostaining was performed using formalin-fixed, paraffin-embedded sections of placentae from three NH cases, four gestational age-matched controls, and, depending on the antibody examined, five to seven full-term controls. The reactivity of immunostaining was assessed by averages of scores assigned by 3 researchers.

RESULTS

On the microvillar surface of STB, the reactions of the antibodies against transferrin receptor 1 (TFR1), transferrin, ferritin, hepcidin, ferroportin, divalent metal transporter-1 (DMT1), hephaestin, and HFE were stronger in NH than in controls. In the cytoplasm, the reactions of antibodies against TFR1, transferrin, ferritin, hepcidin, DMT1, hephaestin, HFE, and ZIP 14 were stronger in NH than in gestational age-matched controls. Among these reactions, those of anti-TFR1 antibody on the surface of STB in NH was especially marked.

DISCUSSION

In the placenta of NH, increases in expressions of TFR1, transferrin, and ferritin of which those of TFR1 were especially marked, reflect increased iron influx from the mother to fetus. The hepcidin observed on the surface and in the cytoplasm of STB of NH is suggested to be from the mother, possibly to compensate for the decreased fetal liver-derived hepcidin.

Prenatal anemia control and anemia in children aged 6-23 months in sub-Saharan Africa

It is unclear whether routine prenatal anemia control interventions can reduce anemia risk in young children. This study examines the associations between prenatal iron supplementation and/or deworming and anemia in children aged 6-23 months in sub-Saharan Africa (SSA). We analyzed data from Demographic and Health Surveys conducted between 2003 and 2014 in 25 SSA countries. The surveys collected data on prenatal iron supplementation and deworming and determined children's hemoglobin levels through blood testing. We assessed the associations between prenatal iron supplementation and/or deworming and anemia using multinomial logistic regression. The study included 31,815 mother-child pairs: 25.0%, 41.4%, and 4.8% of children had mild, moderate, and severe anemia, respectively. Compared with children whose mothers did not take iron and deworming drugs prenatally, the risk of moderate/severe anemia was reduced among children whose mothers took only iron supplements for ≥6 months (odds ratio [OR]: 0.58; 95% confidence interval [CI]: 0.45-0.76); only deworming drugs (OR: 0.73; 95% CI: 0.56-0.93); deworming drugs plus iron for <6 months (OR: 0.79; 95% CI: 0.67-0.93); and deworming drugs plus iron for ≥6 months (OR: 0.77; 95% CI: 0.59-0.99). Prenatal use of only iron for <6 months was not associated with moderate/severe anemia. Prenatal iron and/or deworming drugs had no effect on mild anemia. Prenatal anemia control interventions are associated with reduced risk of moderate/severe anemia but not with mild anemia in young children in SSA. Iron supplements should be taken for ≥6 months or with deworming drugs prenatally to reduce moderate/severe anemia risk in children.

Effects of Octylphenol and Bisphenol A on the Metal Cation Transporter Channels of Mouse Placentas

Octylphenol (OP) and bisphenol A (BPA) are known as endocrine-disrupting chemicals (EDCs). During pregnancy, the expression of steroid hormone receptors is controlled by maternal and fetal nutrition. To evaluate the impact of EDCs during pregnancy, ethinyl estradiol (EE, 0.2 mg/kg/day), OP (50 mg/kg/day), and BPA (50 mg/kg/day) were administered to pregnant mice. The mRNA levels of TRPV6 (transient receptor potential cation channels in subfamily V, member 6) decreased significantly by EE and OP. The PMCA1 (ATPase, Ca⁺⁺ transporting, plasma membrane 1) mRNA and protein levels decreased significantly by EE, OP, and BPA. CTR1 (solute carrier family 31, member 1) and ATP7A (ATPase, Cu⁺⁺ transporting, alpha polypeptide) expression decreased significantly by EE, OP, and BPA. The mRNA levels of IREG1 (iron-regulated transporter, member 1) decreased significantly by EE. Hephaestin (HEPH) mRNA levels decreased significantly by EE, OP, and BPA, and protein levels decreased significantly by BPA. As a result of immunohistochemistry analysis, all cation transporter proteins were found in labyrinth of placenta. To confirm the cytosolic level of cations, levels of cation level in fetal serum were measured. EE, OP, and BPA significantly reduced serum calcium and copper levels, and iron levels were reduced by BPA. Taken together, some EDCs, such as OP and BPA, could modulate the calcium, copper, and iron ion-transporting channels during pregnancy. The fetus relies on the mother for ionic transportation, and, therefore, pregnant women should avoid exposure to cation-channel-disrupting chemicals.

[The imbalance of metal-containing proteins and free metal ions in the amniotic fluid during fetal growth]

The levels of zinc, copper, iron, and magnesium ions, and some of their binding proteins have been investigated in an amniotic fluid under the fetal growth retardation (FGR). FGR, developed under conditions of placental insufficiency, is characterized by a decrease in the content of zinc, iron, and magnesium ions and by an increase in the copper content in the amniotic fluid in the II and III trimesters of pregnancy. During these trimesters the levels of ceruloplasmin, ferritin, and Ca2+,Mg2+-ATPase were lower in FGR, while the level of zinc-a-2-glycoprotein was higher than during the same periods of normal pregnancy. Changes in the parameters studied in the amniotic fluid were associated with developmental disorders of the newborns. These changes obviously have a pathogenetic importance in the development of FGR, and the levels of metal ions and their ratio in the amniotic fluid can be used as markers of the pre- and postnatal pathology.

Proteome Differences in Placenta and Endometrium between Normal and Intrauterine Growth Restricted Pig Fetuses

Uteroplacental tissue plays a key role in substance exchanges between maternal and fetal circulation, and, therefore, in the growth and development of fetuses. In this study, proteomics and western blotting were applied to investigate the changes of proteome in the placenta and endometrium of normal and intrauterine growth restriction (IUGR) porcine fetuses during mid to late pregnancy (D60, 90, and 110 of gestation). Our results showed that proteins participating in cell structure, energy metabolism, stress response, cell turnover, as well as transport and metabolism of nutrients were differentially expressed in placenta and endometrium between normal and IUGR fetuses. Analysis of functions of these proteins suggests reductions in ATP production and nutrients transport, increases in oxidative stress and apoptosis, and impairment of cell metabolism in IUGR fetuses. Collectively, our findings aid in understanding of the mechanisms responsible for uteroplacental dysfunction in IUGR fetus, and are expected to provide new strategies to reduce fetal growth restriction in pigs and other mammals.

Correlation between congenital heart defects and maternal copper and zinc concentrations

BACKGROUND

The aim of this study was to investigate the correlation between maternal concentrations of copper and zinc and the risk of having an infant with a congenital heart defect (CHD).

METHODS

A multi-center hospital-based case-control study was conducted in China. A total of 212 cases and 212 controls were recruited from pregnant women who received prenatal examinations in four tertiary hospitals accredited to perform prenatal diagnosis in the cities of Shenzhen, Zhenzhou, Fuzhou and Wuhan between February 2010 and November 2011. Correlation between CHDs and maternal copper and zinc concentrations was estimated by a 1:1 conditional logistic regression. Also the interaction between copper and zinc was analyzed.

RESULTS

Compared with the controls, mothers with hair copper concentrations of 17.77 μg/g or more were more likely to have a child with a CHD than those with a lower concentration. The adjusted odds ratio was 5.70 (95% confidence interval, 2.58-12.61) for CHDs and 6.32 (95% confidence interval, 2.11-18.92) for conotruncal defects. Zinc concentrations were not significantly different in the case and control groups. The results suggest that mothers whose zinc content was 104.60 μg/g or less did not have a significantly higher risk of having a child with a CHD. No interaction between maternal copper and zinc concentrations was observed in the multiplicative or additive model.

CONCLUSION

Women with excessive copper concentrations have a significantly increased risk of having offspring with a CHD. A low maternal zinc status might have a correlation with CHDs, and an interaction between copper and zinc might exists, but an epidemiological study with a larger sample size is needed to confirm this finding.

Transcriptional regulation of copper metabolism genes in the liver of fetal and neonatal control and iron-deficient rats

Copper and iron metabolism have been known to interact for many years. We have previously shown, during pregnancy, that copper levels in the maternal liver rise as a consequence of iron deficiency, but that levels in the fetal liver decrease. In this paper, we measure expression of genes involved in copper metabolism in fetal and postnatal liver, to test whether alterations can explain this observation. Additionally, we study the extent to which gene expression changes in the latter stages of pregnancy and in the perinatal period. Ctr1 expression levels dropped to term, rising again thereafter. There was no difference in gene expression between control and iron deficient animals. Atox1 expression remained approximately stable until term, and then there was a rise to a maximum at about Day 8. Atp7a expression levels remained constant, except for a brief drop at term. Atp7b levels, in contrast, decreased from a maximum early in gestation to low levels in the term and post-natal livers. Ceruloplasmin expression appeared to be diametrically opposite to Atp7b. The other two metallochaperones showed the same pattern of expression as Atox1, with a decrease to term, a rise at Day 1, or a rise after birth followed by a brief decrease at about Day 3. None of the genes were significantly affected by iron deficiency, suggesting that changes in expression cannot explain the altered copper levels in the fetal and neonatal liver.

Oral cadmium exposure during rat pregnancy: assessment of transplacental micronutrient transport and steroidogenesis at term

Diet is the main source of cadmium (Cd) exposure. Gastrointestinal absorption increases during pregnancy. Cadmium accumulated in the placenta may interfere with nutrient transport to the foetus. Data on the potential of Cd to act as a steroid disruptor of pregnancy are limited. We evaluated the effects of oral Cd exposure during pregnancy on placental function in micronutrient transfer to the foetus and steroidogenesis in Wistar rats (regular 4-day cyclers) that mated with unexposed males. Pregnant rats were randomly assigned to a Cd group exposed orally to 50 mg Cd l(-1) (CdCl(2)xH2O dissolved in demineralized water), ≈ 7.5 mg Cd kg(-1) a day, during 20 days of gestation and control (supplied with demineralized water). Non-pregnant rats were treated under the same experimental conditions. On day 20, all of the rats were killed and samples were taken for element analyses (by electrothermal atomic absorption spectrometry). Progesterone and testosterone were measured in serum and placenta-derived samples (by immunoenzymometric assay and/or enzyme-linked immunosorbent assay). In the exposed rats, Cd increased in blood and organs, more in pregnant rats, and in placenta and foetus whereas zinc increased in liver. Iron decreased in maternal organs and in foetus, whereas zinc decreased in maternal kidney and placenta. Liver copper was lower and kidney copper higher in all pregnant vs. non-pregnant rats. Steroids in serum and placenta did not change. In conclusion, oral Cd exposure during rat pregnancy does not affect progesterone and testosterone at term. Transplacental iron and zinc handover are disrupted, which may put at risk the maintenance of foetal nutrition and viability.

Size dependent translocation and fetal accumulation of gold nanoparticles from maternal blood in the rat

BACKGROUND

There is evidence that nanoparticles (NP) cross epithelial and endothelial body barriers. We hypothesized that gold (Au) NP, once in the blood circulation of pregnant rats, will cross the placental barrier during pregnancy size-dependently and accumulate in the fetal organism by 1. transcellular transport across the hemochorial placenta, 2. transcellular transport across amniotic membranes 3. transport through ~20 nm wide transtrophoblastic channels in a size dependent manner. The three AuNP sizes used to test this hypothesis are either well below, or of similar size or well above the diameters of the transtrophoblastic channels.

METHODS

We intravenously injected monodisperse, negatively charged, radio-labelled 1.4 nm, 18 nm and 80 nm ¹⁹⁸AuNP at a mass dose of 5, 3 and 27 μg/rat, respectively, into pregnant rats on day 18 of gestation and in non-pregnant control rats and studied the biodistribution in a quantitative manner based on the radio-analysis of the stably labelled ¹⁹⁸AuNP after 24 hours.

RESULTS

We observed significant biokinetic differences between pregnant and non-pregnant rats. AuNP fractions in the uterus of pregnant rats were at least one order of magnitude higher for each particle size roughly proportional to the enlarged size and weight of the pregnant uterus. All three sizes of ¹⁹⁸AuNP were found in the placentas and amniotic fluids with 1.4 nm AuNP fractions being two orders of magnitude higher than those of the larger AuNP on a mass base. In the fetuses, only fractions of 0.0006 (30 ng) and 0.00004 (0.1 ng) of 1.4 nm and 18 nm AuNP, respectively, were detected, but no 80 nm AuNP (<0.000004 (<0.1 ng)). These data show that no AuNP entered the fetuses from amniotic fluids within 24 hours but indicate that AuNP translocation occurs across the placental tissues either through transtrophoblastic channels and/or via transcellular processes.

CONCLUSION

Our data suggest that the translocation of AuNP from maternal blood into the fetus is NP-size dependent which is due to mechanisms involving (1) transport through transtrophoblastic channels - also present in the human placenta - and/or (2) endocytotic and diffusive processes across the placental barrier.

Hepcidin and iron homeostasis during pregnancy

Hepcidin is the master regulator of systemic iron bioavailability in humans. This review examines primary research articles that assessed hepcidin during pregnancy and postpartum and report its relationship to maternal and infant iron status and birth outcomes; areas for future research are also discussed. A systematic search of the databases Medline and Cumulative Index to Nursing and Allied Health returned 16 primary research articles including 10 human and six animal studies. Collectively, the results indicate that hepcidin is lower during pregnancy than in a non-pregnant state, presumably to ensure greater iron bioavailability to the mother and fetus. Pregnant women with undetectable serum hepcidin transferred a greater quantity of maternally ingested iron to their fetus compared to women with detectable hepcidin, indicating that maternal hepcidin in part determines the iron bioavailability to the fetus. However, inflammatory states, including preeclampsia, malaria infection, and obesity were associated with higher hepcidin during pregnancy compared to healthy controls, suggesting that maternal and fetal iron bioavailability could be compromised in such conditions. Future studies should examine the relative contribution of maternal versus fetal hepcidin to the control of placental iron transfer as well as optimizing maternal and fetal iron bioavailability in pregnancies complicated by inflammation.

Copper and anesthesia: clinical relevance and management of copper related disorders

Recent research has implicated abnormal copper homeostasis in the underlying pathophysiology of several clinically important disorders, some of which may be encountered by the anesthetist in daily clinical practice. The purpose of this narrative review is to summarize the physiology and pharmacology of copper, the clinical implications of abnormal copper metabolism, and the subsequent influence of altered copper homeostasis on anesthetic management.

Essential but toxic: controlling the flux of iron in the body

Iron is an essential nutrient, but, because it is toxic when present in excess, its levels in the body are tightly controlled. This regulation is affected by controlling the release of iron into the plasma. Most iron enters the plasma from macrophages, which recycle iron from senescent erythrocytes, but dietary iron absorption and the release of hepatocyte storage iron are other major sources. Cellular iron export is mediated by the membrane iron transporter ferroportin 1, in conjunction with an iron oxidase. Hephaestin provides this oxidase activity in the intestine, whereas ceruloplasmin is the oxidase used by most other tissues. The liver-derived peptide hepcidin binds to ferroportin 1 and removes it from the cell surface, thus reducing iron donation to the plasma. The levels of hepcidin, in turn, reflect body iron requirements. At the cellular level, ferroportin 1 can also be regulated independently of hepcidin by hypoxia-inducible factors and the iron regulatory proteins. The hepcidin-ferroportin axis plays a critical role in regulating body iron homeostasis.