Potential function of amniotic fluid in fetal development---novel insights by comparing the composition of human amniotic fluid with umbilical cord and maternal serum at mid and late gestation

Selective bioaccumulation of polystyrene nanoplastics in fetal rat brain and damage to myelin development

Micro(nano)plastic, as a new type of environmental pollutant, have become a potential threat to the life and health of various stages of biology. However, it is not yet clear whether they will affect brain development in the fetal stage. Therefore, this study aims to explore the potential effects of nanoplastics on the development of fetal rat brains. To assess the allocation of NPs (25 nm and 50 nm) in various regions of the fetal brain, pregnant rats were exposed to concentrations (50, 10, 2.5, and 0.5 mg/kg) of PS-NPs. Our results provided evidence of the transplacental transfer of PS-NPs to the fetal brain, with a prominent presence observed in several cerebral regions, notably the cerebellum, hippocampus, striatum, and prefrontal cortex. This distribution bias might be linked to the developmental sequence of each brain region. Additionally, we explored the influence of prenatal exposure on the myelin development of the cerebellum, given its the highest PS-NP accumulation in offspring. Compared with control rats, PS-NPs exposure caused a significant reduction in myelin basic protein (MBP) and myelin oligodendrocyte glycoprotein (MOG) expression, a decrease in myelin thickness, an increase in cell apoptosis, and a decline in the oligodendrocyte population. These effects gave rise to motor deficits. In conclusion, our results identified the specific distribution of NPs in the fetal brain following prenatal exposure and revealed that prenatal exposure to PS-NPs can suppress myelin formation in the cerebellum of the fetus.

Immersed in a reservoir of potential: amniotic fluid-derived extracellular vesicles

This review aims to encapsulate the current knowledge in extracellular vesicles extracted from amniotic fluid and amniotic fluid derived stem/stromal cells. Amniotic fluid (AF) bathes the developing fetus, providing nutrients and protection from biological and mechanical dangers. In addition to containing a myriad of proteins, immunoglobulins and growth factors, AF is a rich source of extracellular vesicles (EVs). These vesicles originate from cells in the fetoplacental unit. They are biological messengers carrying an active cargo enveloped within the lipid bilayer. EVs in reproduction are known to play key roles in all stages of pregnancy, starting from fertilisation through to parturition. The intriguing biology of AF-derived EVs (AF-EVs) in pregnancy and their untapped potential as biomarkers is currently gaining attention. EV studies in numerous animal and human disease models have raised expectations of their utility as therapeutics. Amniotic fluid stem cell and mesenchymal stromal cell-derived EVs (AFSC-EVs) provide an established supply of laboratory-made EVs. This cell-free mode of therapy is popular as an alternative to stem cell therapy, revealing similar, if not better therapeutic outcomes. Research has demonstrated the successful application of AF-EVs and AFSC-EVs in therapy, harnessing their anti-inflammatory, angiogenic and regenerative properties. This review provides an overview of such studies and discusses concerns in this emerging field of research.

Case report: Treatment of Wilson's disease by human amniotic fluid administration

Background

Wilson's disease (WD) is not an uncommon genetic disease in clinical practice. However, the current WD therapies have limitations. The effectiveness of stem cell therapy in treating WD has yet to be verified, although a few animal studies have shown that stem cell transplantation could partially correct the abnormal metabolic phenotype of WD. In this case report, we present the therapeutic effect of human amniotic fluid containing stem cells in one WD patient.

Case presentation

A 22-year-old Chinese woman was diagnosed with WD 1 year ago in 2019. The available drugs were not effective in managing the progressive neuropsychiatric symptoms. We treated the patient with pre-cultured human amniotic fluid containing stem cells. Amniotic fluid was collected from pregnant women who underwent induced labor at a gestational age of 19-26 weeks, and then, the fluid was cultured for 2 h to allow stem cell expansion. Cultured amniotic fluid that contained amniotic fluid derived stem cells (AFSC) in the range of approximately 2.8-5.5 × 104/ml was administrated by IV infusion at a rate of 50-70 drops per minute after filtration with a 300-mu nylon mesh. Before the infusion of amniotic fluid, low-molecular-weight heparin and dexamethasone were successively administrated. The patient received a total of 12 applications of amniotic fluid from different pregnant women, and the treatment interval depended on the availability of amniotic fluid. The neuropsychiatric symptoms gradually improved after the stem cell treatment. Dystonia, which included tremor, chorea, dysphagia, dysarthria, and drooling, almost disappeared after 1.5 years of follow-up. The Unified Wilson's Disease Rating Scale score of the patient decreased from 72 to 10. Brain magnetic resonance imaging (MRI) showed a reduction in the lesion area and alleviation of damage in the central nervous system, along with a partial recovery of the lesion to the normal condition. The serum ceruloplasmin level was elevated from undetectable to 30.8 mg/L, and the 24-h urinary copper excretion decreased from 171 to 37 μg. In addition, amniotic fluid transplantation also alleviates hematopoietic disorders. There were no adverse reactions during or after amniotic fluid administration.

Conclusion

Amniotic fluid administration, through which stem cells were infused, significantly improves the clinical outcomes in the WD patient, and the finding may provide a novel approach for managing WD effectively.

Simulation-based development: shaping clinical procedures for extra-uterine life support technology

BACKGROUND

Research into Artificial Placenta and Artificial Womb (APAW) technology for extremely premature infants (born < 28 weeks of gestation) is currently being conducted in animal studies and shows promising results. Because of the unprecedented nature of a potential treatment and the high-risk and low incidence of occurrence, translation to the human condition is a complex task. Consequently, the obstetric procedure, the act of transferring the infant from the pregnant woman to the APAW system, has not yet been established for human patients. The use of simulation-based user-centered development allows for a safe environment in which protocols and devices can be conceptualized and tested. Our aim is to use participatory design principles in a simulation context, to gain and integrate the user perspectives in the early design phase of a protocol for this novel procedure.

METHODS

Simulation protocols and prototypes were developed using an iterative participatory design approach; usability testing, including general and task-specific feedback, was obtained from participants with clinical expertise from a range of disciplines. The procedure made use of fetal and maternal manikins and included animations and protocol task cards.

RESULTS

Physical simulation with the active participation of clinicians led to the diffusion of tacit knowledge and an iteratively formed shared understanding of the requirements and values that needed to be implemented in the procedure. At each sequel, participant input was translated into simulation protocols and design adjustments.

CONCLUSION

This work demonstrates that simulation-based participatory design can aid in shaping the future of clinical procedure and product development and rehearsing future implementation with healthcare professionals.

Stratification of Amniotic Fluid Cells and Amniotic Fluid by Sex Opens Up New Perspectives on Fetal Health

Amniotic fluid is essential for fetus wellbeing and is used to monitor pregnancy and predict fetal outcomes. Sex affects health and medicine from the beginning of life, but knowledge of its influence on cell-depleted amniotic fluid (AF) and amniotic fluid cells (AFCs) is still neglected. We evaluated sex-related differences in AF and in AFCs to extend personalized medicine to prenatal life. AFCs and AF were obtained from healthy Caucasian pregnant women who underwent amniocentesis at the 16th-18th week of gestation for advanced maternal age. In the AF, inflammation biomarkers (TNFα, IL6, IL8, and IL4), malondialdehyde, nitrites, amino acids, and acylcarnitines were measured. Estrogen receptors and cell fate (autophagy, apoptosis, senescence) were measured in AFCs. TNFα, IL8, and IL4 were higher in female AF, whereas IL6, nitrites, and MDA were similar. Valine was higher in male AF, whereas several acylcarnitines were sexually different, suggesting a mitochondrial involvement in establishing sex differences. Female AFCs displayed higher expression of ERα protein and a higher ERα/ERβ ratio. The ratio of LC3II/I, an index of autophagy, was higher in female AFCs, while LC3 gene was similar in both sexes. No significant sex differences were found in the expression of the lysosomal protein LAMP1, while p62 was higher in male AFCs. LAMP1 gene was upregulated in male AFCs, while p62 gene was upregulated in female ones. Finally, caspase 9 activity and senescence linked to telomeres were higher in female AFCs, while caspase 3 and β-galactosidase activities were similar. This study supports the idea that sex differences start very early in prenatal life and influence specific parameters, suggesting that it may be relevant to appreciate sex differences to cover knowledge gaps. This might lead to improving the diagnosis of risk prediction for pregnancy complications and achieving a more satisfactory monitoring of fetus health, even preventing future diseases in adulthood.

Placental-Derived Biomaterials and Their Application to Wound Healing: A Review

Chronic wounds are associated with considerable patient morbidity and present a significant economic burden to the healthcare system. Often, chronic wounds are in a state of persistent inflammation and unable to progress to the next phase of wound healing. Placental-derived biomaterials are recognized for their biocompatibility, biodegradability, angiogenic, anti-inflammatory, antimicrobial, antifibrotic, immunomodulatory, and immune privileged properties. As such, placental-derived biomaterials have been used in wound management for more than a century. Placental-derived scaffolds are composed of extracellular matrix (ECM) that can mimic the native tissue, creating a reparative environment to promote ECM remodeling, cell migration, proliferation, and differentiation. Reliable evidence exists throughout the literature to support the safety and effectiveness of placental-derived biomaterials in wound healing. However, differences in source (i.e., anatomical regions of the placenta), preservation techniques, decellularization status, design, and clinical application have not been fully evaluated. This review provides an overview of wound healing and placental-derived biomaterials, summarizes the clinical results of placental-derived scaffolds in wound healing, and suggests directions for future work.

Creatine metabolism at the uterine-placental interface throughout gestation in sheep†

The placenta requires high levels of adenosine triphosphate to maintain a metabolically active state throughout gestation. The creatine-creatine kinase-phosphocreatine system is known to buffer adenosine triphosphate levels; however, the role(s) creatine-creatine kinase-phosphocreatine system plays in uterine and placental metabolism throughout gestation is poorly understood. In this study, Suffolk ewes were ovariohysterectomized on Days 30, 50, 70, 90, 110 and 125 of gestation (n = 3-5 ewes/per day, except n = 2 on Day 50) and uterine and placental tissues subjected to analyses to measure metabolites, mRNAs, and proteins related to the creatine-creatine kinase-phosphocreatine system. Day of gestation affected concentrations and total amounts of guanidinoacetate and creatine in maternal plasma, amniotic fluid and allantoic fluid (P < 0.05). Expression of mRNAs for arginine:glycine amidinotransferase, guanidinoacetate methyltransferase, creatine kinase B, and solute carrier 16A12 in endometria and for arginine:glycine amidinotransferase and creatine kinase B in placentomes changed significantly across days of gestation (P < 0.05). The arginine:glycine amidinotransferase protein was more abundant in uterine luminal epithelium on Days 90 and 125 compared to Days 30 and 50 (P < 0.01). The chorionic epithelium of placentomes expressed guanidinoacetate methyltransferase and solute carrier 6A13 throughout gestation. Creatine transporter (solute carrier 6A8) was expressed by the uterine luminal epithelium and trophectoderm of placentomes throughout gestation. Creatine kinase (creatine kinase B and CKMT1) proteins were localized primarily to the uterine luminal epithelium and to the placental chorionic epithelium of placentomes throughout gestation. Collectively, these results demonstrate cell-specific and temporal regulation of components of the creatine-creatine kinase-phosphocreatine system that likely influence energy homeostasis for fetal-placental development.

A Randomized Trial of Inpatient and Home-Based Maternal Oral Hydration Therapy in Isolated Oligohydramnios and Its Effect on Amniotic Fluid Index and Perinatal Outcome

Background Isolated oligohydramnios, without any known fetal/maternal abnormality, may be associated with insufficient oral intake (such as water, glucose, and rehydration therapy). Therefore, the present study was conducted to assess the improvement following maternal hydration. Method A total of 50 cases of isolated oligohydramnios (other high-risk pregnancy conditions not present) were included in the study (25 in each group). Patients were encouraged for an additional 2 liters of oral rehydration solution intake daily along with regular diet. The fluid intake was unsupervised in the home group and supervised in the hospital group. Serial amniotic fluid index (AFI) measurements and fetal monitoring were performed. Birth weight and APGAR scores were recorded, and data were analyzed. Results The two groups were comparable in terms of demographics and baseline laboratory findings. AFI significantly improved in the hospital group compared to the home group (p-value: <0.001). Birth weight, placental weight, and APGAR scores were also significantly better in the hospital group than in the home group. Conclusion Maternal oral hydration therapy improves the amniotic fluid volume and subsequently improves the perinatal outcome. Due to poor compliance with home-based treatment, institution of supervised hydration therapy is recommended.

Dietary sialic acids: distribution, structure, and functions

Sialic acids (Sias), a group of over 50 structurally distinct acidic saccharides on the surface of all vertebrate cells, are neuraminic acid derivatives. They serve as glycan chain terminators in extracellular glycolipids and glycoproteins. In particular, Sias have significant implications in cell-to-cell as well as host-to-pathogen interactions and participate in various biological processes, including neurodevelopment, neurodegeneration, fertilization, and tumor migration. However, Sia is also present in some of our daily diets, particularly in conjugated form (sialoglycans), such as those in edible bird's nest, red meats, breast milk, bovine milk, and eggs. Among them, breast milk, especially colostrum, contains a high concentration of sialylated oligosaccharides. Numerous reviews have concentrated on the physiological function of Sia as a cellular component of the body and its relationship with the occurrence of diseases. However, the consumption of Sias through dietary sources exerts significant influence on human health, possibly by modulating the gut microbiota's composition and metabolism. In this review, we summarize the distribution, structure, and biological function of particular Sia-rich diets, including human milk, bovine milk, red meat, and egg.

Cell-Free Amniotic Fluid and Regenerative Medicine: Current Applications and Future Opportunities

Amniotic fluid (AF) provides critical biological and physical support for the developing fetus. While AF is an excellent source of progenitor cells with regenerative properties, recent investigations indicate that cell-free AF (cfAF), which consists of its soluble components and extracellular vesicles, can also stimulate regenerative and reparative activities. This review summarizes published fundamental, translational, and clinical investigations into the biological activity and potential use of cfAF as a therapeutic agent. Recurring themes emerge from these studies, which indicate that cfAF can confer immunomodulatory, anti-inflammatory, and pro-growth characteristics to the target cells/tissue with which they come into contact. Another common observation is that cfAF seems to promote a return of cells/tissue to a homeostatic resting state when applied to a model of cell stress or disease. The precise mechanisms through which these effects are mediated have not been entirely defined, but it is clear that cfAF can safely and effectively treat cutaneous wounds and perhaps orthopedic degenerative conditions. Additional applications are currently being investigated, but require further study to dissect the fundamental mechanisms through which its regenerative effects are mediated. By doing so, rational design can be used to fully unlock its potential in the biotechnology lab and in the clinic.

Toward better assessments of developmental toxicity using stem cell-based in vitro embryogenesis models

In the past few decades, pluripotent stem cells have been explored as nonanimal alternatives to assess the developmental toxicity of chemicals. To date, numerous versions of stem cell-based assays have been reported that are allegedly effective. Nonetheless, none of the assays has become the gold standard in developmental toxicity assessment. Why? This article discusses several issues in the hope of facilitating the refinement of stem cell assays and their acceptance as the cornerstone in predictive developmental toxicology. Each stem cell assay is built on a limited representation of embryogenesis, so that multiple assays are needed to detect the diverse effects of various chemicals. To validate and compare the strengths and weaknesses of individual assays, standardized lists of reference chemicals should be established. Reference lists should consist of exposures defined by toxicokinetic data, namely maternal plasma concentrations that cause embryonic death or malformations, and also by the effects on the molecular machineries that control embryogenesis. Although not entirely replacing human or animal tests, carefully selected stem cell assays should serve as practical and ethical alternatives to proactively identify chemical exposures that disturb embryogenesis. To achieve this goal, unprecedented levels of coordination and conviction are required among research and regulatory communities.

Evaluation of Biochemical Composition of Amniotic and Allantoic Fluids at Different Stages of Pregnancy in Queens

Simple Summary

Fetal fluid contents influence growth and development, fetal wellbeing and a protection mechanism for the fetus itself. Very little is known about the composition of fetal fluids during pregnancy in cats and about changes in contents that occur throughout gestation. In this study, initial results regarding the biochemical composition of fetal fluids are provided. A comparison with maternal serum was also performed. A complete understanding of trends can be helpful for the early detection of some pathologies during pregnancy, such as in humans and mares.

Abstract

Fetal fluid contents have functions in protecting fetuses and are essential for fetal development and maturation. However, little is known about the exact physiological functions of fetal fluids in fetal development, as well as the changing composition throughout the gestational period in cats. In this study, the biochemical composition of amniotic (AMN) and allantoic (ALL) fluids was investigated, as well as in the maternal serum of pregnant queens. Eighteen queens were included in this study and assigned to six different groups, D₂₀, D₂₅, D₃₀, D₄₀, D₄₅ and D₆₀, according to the gestational stage of fetal development. A total of 44 amniotic and 37 allantoic samples were collected. Fetal fluids contained lesser concentrations of alanine aminotransferase, albumin, cholesterol, triglycerides, creatine kinase, amylase, total protein and globulin than maternal serum. Other variables, such as aspartate aminotransferase, gamma-glutamyl transferase, bilirubin and alkaline phosphatase, were in different concentrations at specific stages of gestation when compared to maternal serum. There were no differences between fetal fluids and maternal serum for lactate dehydrogenase, urea, lipase or glucose concentrations. There were greater concentrations of creatinine in amniotic fluid than in allantoic fluid or maternal serum. Based on the results of this study, fetal fluids do not accumulate as a result of the simple filtration of maternal blood, but rather, the fetus produces many of these components as a consequence of organ development and maturation.

A Critical Review on Transplacental Transfer of Per- and Polyfluoroalkyl Substances: Prenatal Exposure Levels, Characteristics, and Mechanisms

Prenatal exposure to perfluoroalkyl and polyfluoroalkyl substances (PFASs) has aroused public concerns as it can pose multiple health threats to pregnant women and cause adverse birth outcomes for fetuses. In previous studies, the prenatal exposure levels and transplacental transfer efficiencies (TTE) of PFASs have been reported and discussed. Specifically, the binding affinities between PFASs and some transporters were determined, demonstrating that the TTE values of PFASs are highly dependent on their binding behaviors. To summarize primary findings of previous studies and propose potential guidance for future research, this article provides a systematic overview on levels and characteristics of prenatal exposure to PFASs worldwide, summarizes relationships between TTE values and structures of PFASs, and discusses possible transplacental transfer mechanisms, especially for the combination between PFASs and transporters. Given the critical roles of transporters in the transplacental transfer of PFASs, we conducted molecular docking to further clarify the binding behaviors between PFASs and the selected transporters. We proposed that the machine learning can be a superior method to predict and reveal behaviors and mechanisms of the transplacental transfer of PFASs. In total, this is the first review providing a comprehensive overview on the prenatal exposure levels and transplacental transfer mechanisms of PFASs.

Placental Tissues as Biomaterials in Regenerative Medicine

Placental tissues encompass all the tissues which support fetal development, including the placenta, placental membrane, umbilical cord, and amniotic fluid. Since the 1990s there has been renewed interest in the use of these tissues as a raw material for regenerative medicine applications. Placental tissues have been extensively studied for their potential contribution to tissue repair applications. Studies have attributed their efficacy in augmenting the healing process to the extracellular matrix scaffolds rich in collagens, glycosaminoglycans, and proteoglycans, as well as the presence of cytokines within the tissues that have been shown to stimulate re-epithelialization, promote angiogenesis, and aid in the reduction of inflammation and scarring. The compositions and properties of all birth tissues give them the potential to be valuable biomaterials for the development of new regenerative therapies. Herein, the development and compositions of each of these tissues are reviewed, with focus on the structural and signaling components that are relevant to medical applications. This review also explores current configurations and recent innovations in the use of placental tissues as biomaterials in regenerative medicine.

Extraembryonic Mesenchymal Stromal/Stem Cells in Liver Diseases: A Critical Revision of Promising Advanced Therapy Medicinal Products

Liver disorders have been increasing globally in recent years. These diseases are associated with high morbidity and mortality rates and impose high care costs on the health system. Acute liver failure, chronic and congenital liver diseases, as well as hepatocellular carcinoma have been limitedly treated by whole organ transplantation so far. But novel treatments for liver disorders using cell-based approaches have emerged in recent years. Extra-embryonic tissues, including umbilical cord, amnion membrane, and chorion plate, contain multipotent stem cells. The pre-sent manuscript discusses potential application of extraembryonic mesenchymal stromal/stem cells, focusing on the management of liver diseases. Extra-embryonic MSC are characterized by robust and constitutive anti-inflammatory and anti-fibrotic properties, indicating as therapeutic agents for inflammatory conditions such as liver fibrosis or advanced cirrhosis, as well as chronic inflammatory settings or deranged immune responses.

Biodegradation of poly(L-lactic acid) and poly(ε-caprolactone) patches by human amniotic fluid in an in-vitro simulated fetal environment

Open spina bifida or myelomeningocele (MMC) is a devastating neurologic congenital defect characterized by primary failure of neural tube closure of the spinal column during the embryologic period. Cerebrospinal fluid leak caused by the MMC spinal defect in the developing fetus can result in a constellation of encephalic anomalies that include hindbrain herniation and hydrocephalus. The exposure of extruded spinal cord to amniotic fluid also poses a significant risk for inducing partial or complete paralysis of the body parts beneath the spinal aperture by progressive spinal cord damage in-utero. A randomized trial demonstrated that prenatal repair by fetal surgery, sometimes using patches, to cover the exposed spinal cord with a watertight barrier is effective in reducing the postnatal neurologic morbidity as evidenced by decreased incidence and severity of postnatal hydrocephalus and the reduced need for ventricular-peritoneal shunting. Currently, the use of inert or collagen-based patches are associated with high costs and inadequate structural properties. Specifically, the inert patches do not degrade after implantation, causing the need for a post-natal removal surgery associated with trauma for the newborn. Our present study is aimed towards in-vitro degradation studies of a newly designed patch, which potentially can serve as a superior alternative to existing patches for MMC repair. This novel patch was fabricated by blending poly(l-lactic acid) and poly(ε-caprolactone). The 16-week degradation study in amniotic fluid was focused on tracking changes in crystallinity and mechanical properties. An additional set of designed patches was exposed to phosphate-buffered saline (PBS), as a time-paired control. Crystallinity studies indicate the progress of hydrolytic degradation of the patch in both media, with a preference to bulk erosion in phosphate buffered saline and surface erosion in amniotic fluid. Mechanical testing results establish that patch integrity is not compromised up to 16 weeks of exposure either to body fluids analog (PBS) or to amniotic fluid.

Amniotic fluid stabilized lipid nanoparticles for in utero intra-amniotic mRNA delivery

Congenital disorders resulting in pathological protein deficiencies are most often treated postnatally with protein or enzyme replacement therapies. However, treatment of these disorders in utero before irreversible disease onset could significantly minimize disease burden, morbidity, and mortality. One possible strategy for the prenatal treatment of congenital disorders is in utero delivery of messenger RNA (mRNA). mRNA is a nucleic acid therapeutic that has previously been investigated as a platform for protein replacement therapies and gene editing technologies. While viral vectors have been explored to induce intracellular expression of mRNA, they are limited in their clinical application due to risks associated with immunogenicity and genomic integration. As an alternative to viral vectors, safe and efficient in utero mRNA delivery can be achieved using ionizable lipid nanoparticles (LNPs). While LNPs have demonstrated potent in vivo mRNA delivery to the liver following intravenous administration, intra-amniotic delivery has the potential to deliver mRNA to cells and tissues beyond those in the liver, such as in the skin, lung, and digestive tract. However, LNP stability in fetal amniotic fluid and how this stability affects mRNA delivery has not been previously investigated. Here, we engineered a library of LNPs using orthogonal design of experiments (DOE) to evaluate how LNP structure affects their stability in amniotic fluid ex utero and whether a lead candidate identified from these stability measurements enables intra-amniotic mRNA delivery in utero. We used a combination of techniques including dynamic light scattering (DLS), transmission electron microscopy (TEM), and chromatography followed by protein content quantification to screen LNP stability in amniotic fluids. These results identified multiple lead LNP formulations that are highly stable in amniotic fluids ranging from small animals to humans, including mouse, sheep, pig, and human amniotic fluid samples. We then demonstrate that stable LNPs from the ex utero screen in mouse amniotic fluid enabled potent mRNA delivery in primary fetal lung fibroblasts and in utero following intra-amniotic injection in a murine model. This exploration of ex utero stability in amniotic fluids demonstrates a means by which to identify novel LNP formulations for prenatal treatment of congenital disorders via in utero mRNA delivery.

Heavy metal ion concentration in the amniotic fluid of preterm and term pregnancies from two cities with different industrial output

The growth and development of the fetus is a complex phenomenon that can be influenced by several variables. High quantities of heavy metal ions in the amniotic fluid have been linked to poor health, especially in industrial, polluted and poor areas. The aim of the present study was to assess the differences in the concentration of these ions between preterm (weeks 15-37) and term pregnancies (starting at week 37). Another objective was to compare pregnancies from two cities with different industry levels. Two sample lots from two Romanian cities were analyzed. A total of 100 patients from Timisoara were compared with 60 from Petrosani, a heavy industry city in Romania. Demographic data were collected, and amniocentesis was performed on all women. Lead (Pb), copper (Cu), nickel (Ni), cadmium (Cd), arsenic (As), iron (Fe) and zinc (Zn) concentrations were assessed. Descriptive and analytical statistics were performed using the Mann-Whitney U test for non-parametric data and the Fisher's exact test for categorical data. In addition, categorical data was represented graphically. In the Timisoara cohort, the differences in heavy metal concentrations between preterm and term pregnancies were not statistically significant. In the Petrosani cohort, however, the concentrations of Zn (P=0.02606) and Cd (P=0.01512) were higher in preterm than in term pregnancies. When comparing the two cohorts as a whole, the concentration of Pb (P=0.04513), Cd (P=0.00002), As (P=0.03027) and Zn (P<0.00001) were higher in the patients from Petrosani than in those from Timisoara. Only Cu concentrations were higher in the Timisoara cohort (P<0.00001). The concentrations of Ni (P=0.78150) and Fe (P=0.44540) did not differ statistically. Thus, amniocentesis is an important diagnostic and exploratory tool in determining differences in the concentrations of elements such as heavy metal ions. Research over a longer period of time should be carried out to examine the relation between heavy metal ions concentration and possible postnatal health outcomes.

Prebiotic Supplementation During Pregnancy Modifies the Gut Microbiota and Increases Metabolites in Amniotic Fluid, Driving a Tolerogenic Environment In Utero

The gut microbiota is influenced by environmental factors such as food. Maternal diet during pregnancy modifies the gut microbiota composition and function, leading to the production of specific compounds that are transferred to the fetus and enhance the ontogeny and maturation of the immune system. Prebiotics are fermented by gut bacteria, leading to the release of short-chain fatty acids that can specifically interact with the immune system, inducing a switch toward tolerogenic populations and therefore conferring health benefits. In this study, pregnant BALB/cJRj mice were fed either a control diet or a diet enriched in prebiotics (Galacto-oligosaccharides/Inulin). We hypothesized that galacto-oligosaccharides/inulin supplementation during gestation could modify the maternal microbiota, favoring healthy immune imprinting in the fetus. Galacto-oligosaccharides/inulin supplementation during gestation increases the abundance of Bacteroidetes and decreases that of Firmicutes in the gut microbiota, leading to increased production of fecal acetate, which was found for the first time in amniotic fluid. Prebiotic supplementation increased the abundance of regulatory B and T cells in gestational tissues and in the fetus. Interestingly, these regulatory cells remained later in life. In conclusion, prebiotic supplementation during pregnancy leads to the transmission of specific microbial and immune factors from mother to child, allowing the establishment of tolerogenic immune imprinting in the fetus that may be beneficial for infant health outcomes.

The Amniotic Fluid Cell-Free Transcriptome Provides Novel Information about Fetal Development and Placental Cellular Dynamics

The amniotic fluid (AF) is a complex biofluid that reflects fetal well-being during development. AF con be divided into two fractions, the supernatant and amniocytes. The supernatant contains cell-free components, including placenta-derived microparticles, protein, cell-free fetal DNA, and cell-free fetal RNA from the fetus. Cell-free mRNA (cfRNA) analysis holds a special position among high-throughput analyses, such as transcriptomics, proteomics, and metabolomics, owing to its ease of profiling. The AF cell-free transcriptome differs from the amniocyte transcriptome and alters with the progression of pregnancy and is often associated with the development of various organ systems including the fetal lung, skin, brain, pancreas, adrenal gland, gastrointestinal system, etc. The AF cell-free transcriptome is affected not only by normal physiologies, such as fetal sex, gestational age, and fetal maturity, but also by pathologic mechanisms such as maternal obesity, and genetic syndromes (Down, Edward, Turner, etc.), as well as pregnancy complications (preeclampsia, intrauterine growth restriction, preterm birth, etc.). cfRNA in the amniotic fluid originates from the placenta and fetal organs directly contacting the amniotic fluid as well as from the fetal plasma across the placenta. The AF transcriptome may reflect the fetal and placental development and therefore aid in the monitoring of normal and abnormal development.

Comparative evaluation of amniotic fluid as an alternative to fetal bovine serum in the maintenance of Leishmania major and Toxoplasma gondii

This study aimed to evaluate the efficacy of amniotic fluid (AF) as an alternative to fetal bovine serum (FBS) in the maintenance of Leishmania major promastigotes and Toxoplasma gondii tachyzoites. AF was collected by an obstetrician using sterile syringes during a cesarean section. The culture medium was supplemented with 5 different concentrations of FBS or AF including 2, 5, 10, 20, and 30%. These concentrations were used to maintain both mentioned parasites. L. major was maintained at temperatures 4 and 24 °C and examined once a week for 4 weeks, while T. gondii was maintained at temperatures 4, 24, and 37 °C and examined at hours 24, 48, 72, and 96. For L. major, at both 4 and 24 °C, we observed no significant difference between FBS and AF on day 7. However, on days 14, 21, and 28, the difference between FBS and AF was significant at both temperatures. For T. gondii, no significant difference was observed between FBS and AF at hour 24 and all temperatures. However, this difference was significant at hours 48, 72, and 96 and all temperatures. According to our results, although FBS had a greater efficacy than AF in the growth of L. major and the survival of T. gondii, the number of promastigotes increased over time in AF-containing medium and the number of tachyzoites reduced slowly with a mild slop. Therefore, AF can be a potential alternative to FBS.

Maternal environmental enrichment modulates the immune response against an inflammatory challenge during gestation and protects the offspring

The production of pro-inflammatory cytokines during inflammatory processes has been associated with preterm birth (PTB) and fetal injury in humans and mice. We previously demonstrated that exposition to an enriched environment (EE), defined as a noninvasive and biological significant stimulus of the sensory pathway combined with voluntary physical activity, prevented PTB and perinatal death induced by the systemic administration of bacterial lipopolysaccharide (LPS) in mice. This work aimed to analyze whether EE modulates the immune response to the inflammatory process induced by LPS in peripheral blood and the amniotic fluid (AF). We observed that EE modulated maternal white blood cell count and its response to LPS. Furthermore, we found higher levels of IL-10 and a higher percentage of B cells in AF from EE exposed mothers compared to controls. Albeit LPS significantly increased IL-6 levels in AF from both groups, it was 3.6 times higher in control environment (CE) exposed group when compared to EE. Similarly, levels of IL-22 were significantly increased by LPS in both groups, but it was 6.7 times higher in EE group. Interestingly, levels of PGE2 in AF were only increased in the EE-LPS treated group, and a positive correlation between IL-22 and PGE2 levels was observed. During lactation, EE prevented LPS-induced delay in physical landmarks analyzed to assess offspring development. Our results suggest that EE modulates the immune response to systemic LPS-administration protecting the offspring. We propose that an EE-like protocol could be designed for pregnant women aiming at preventing the sequelae present in premature children.

Amniotic Fluid Transplantation Alleviates Hematopoietic Deficits in Experimental Rat Aplastic Anemia

Background

Hematopoietic stem cell (HSC) transplantation is the most effective therapy for hematopoietic impairment. However, maintenance and self-renewal of HSCs in culture is still a central focus of HSC research. It is known that amniotic fluid contains a heterologous population of stem cells (AFSCs) and nutrients as well as various types of growth factors. We hypothesize that AFSCs may be expanded in vitro in pure amniotic fluid.

Material/Methods

Amniotic fluid with transparent appearance was harvested at embryo age of 13.5–15.5 days in rats and was placed in a cell culture CO₂ incubator. The cell number in the amniotic fluid was counted before and after culture of amniotic fluid. Then, the effect of amniotic fluid transplantation on 5-fluorouracil combined with busulfan induced-rat aplastic anemia was investigated.

Results

We found that after a short time (about 30 min) culture, the number of AFSCs expanded more than 100-fold. Flow cytometry showed that there was a population of cells expressing hematopoietic markers CD45 and CD34 in addition to a higher proportional of mesenchymal stem cells (MSCs) markers CD29 and CD90. Transplantation of the expanded AFSCs possessed significant therapeutic effect in toxic chemicals induced-aplastic anemia rats, manifested by decreasing animal mortality and alleviating the reduction of the 3 lineages of hematopoietic cells in blood.

Conclusions

Our observation for the first time demonstrates that amniotic fluid is an excellent medium for stem cells to maintain “stemness” proliferation and provides novel evidence to support the potential use of in vitro-expanded AFSCs for the treatment of hematopoietic disorders.

Is chlorine and sodium levels in the amniotic fluid a new marker for fetal lung maturation and RDS severity?

BACKGROUND

Amniotic fluid (AF) is a dynamic liquid whose contents vary according to the needs of the fetus. Levels of the amniotic components have been used in numerous studies as potential biomarkers to screen pregnancy-related abnormalities. As a reflection of Na⁺ and Cl^- levels of fetal lung fluid, amniotic fluid's Na⁺ and Cl^- levels can be used as an indicator of lung maturation in the newborn period. This study aimed to investigate whether Na⁺ and Cl^- levels in the amniotic fluid would be a new marker to determine the severity of respiratory distress and pulmonary maturation in the newborn.

METHODS

This prospective cohort study was conducted at Hacettepe University Neonatal Intensive Care Unit. One hundred twenty single infants who were delivered with the cesarean section between January 2015 and March 2016 were included. Na⁺ and Cl^- levels were measured from AF.

RESULTS

There were 46 of 120 infants (33.3%) in Group-1 and 74 infants (66.7%) in Group-2. Na + and Cl^- levels of the AF of Group-1 were higher than Group 2 and this was statistically significant (p < .001/p: .01, respectively). Na⁺ and Cl^- levels of the AF were significantly higher in infants who needed surfactant (p < .001/p: .001, respectively).

CONCLUSION

Our results showed that Na⁺ and Cl^- levels of the AF can be used as an indicator of infant lung maturation.

Do Maternal Microbes Shape Newborn Oral Microbes?

Strong evidence suggests that the early composition of the oral microbiota of neonates plays an important role for the postnatal development of the oral health or immune system. However, the relationship between the maternal microbiome and the initial neonatal microbiome remains unclear. In this study, 25 pregnant women and their neonates were recruited, and the samples were collected from the maternal oral cavity, amniotic fluid, placenta and neonatal oral cavity. High-throughput sequencing of 16S rRNA was performed using the Illumina MiSeq platform to analyze the correlation with microbial community structure between the maternal and the neonatal oral cavity. The results indicated that the number of shared OTUs was up to 635 in four groups. The PCoA showed that there were certain similarities in the microbial community structure of the four groups. The dominant bacterial genera of the shared OTUs were consistent with human oral microbes, including Streptococcus, Fusobacterium and Prevotella. The results showed that there might be a correlation between the maternal and neonatal oral microbiome, through the amniotic fluid and placenta.

Gestational Age-Dependent Fetal Fluid Dynamics in the Ovine Developmental Model: Establishment of Surrogate Markers for the Differentiation of Stem Cell Origin

The ovine developmental model represents the standard in vivo model for studies involving maternofetal physiology, amniotic fluid (AF) research, and fetal cell therapy prior to human clinical use. Although being close to the human fetal anatomy, 2 separate extraembryonic fluid compartments remain during gestation, known as the amnion and the allantois. A clear distinction between AF versus allantoic fluid (AL) is therefore indispensable for correct scientific conclusions with regard to human translation. In the presented study, the biochemical composition of AF and AL was evaluated in ovine gravid uteri postmortem (n = 31) over the entire gestation. Four parameters, consisting of Na+, Cl-, Mg2+, and total protein, have been found to allow for specific discrimination of the 2 fetal fluids at all gestational phases and therefore as potential surrogate parameters for gestational age. In addition, volumetric changes of the developing fetus and the 2 fetal fluid cavities were analyzed by contrast-enhanced computed tomography (n = 12). AF showed a significant, linear volumetric increase over gestation, whereas AL volume maintained relatively static independent of gestational age. These results serve as a basis for future studies by providing surrogate markers enabling a reliable distinction of isolated fetal fluids and contained cells in the ovine developmental model over the entire gestation.

A new organ preservation solution for static cold storage of the liver. Amniotic fluid

Purpose:

To evaluate the effect of amniotic fluid in liver preservation in organ transplantation, and compare it with standard preservation solutions.

Methods:

The groups consisted of Group 1: Ringer Lactate (RL) group, Group 2: HTK group, Group 3: UW group, Group 4: AF group. The livers of rats from Group 1, 2, 3, and 4 were perfused and placed into falcon tubes containing RL, HTK, UW, and AF solutions at +4‎°C, respectively. The tubes were stored for 12 hours in the refrigerator at +4°C. Tissue samples were taken at the 6^th and 12^th hours for histopathological examinations of the perfused livers, and storage solutions for biochemical analyzes at 6^th and 12^th hours.

Results:

AF was shown to maintain organ viability by reducing the number of cells undergoing apoptosis. Histopathological changes such as sinusoidal dilatation, hydropic degeneration, and focal necrosis were found to be similar to the groups in which the standard organ preservation solutions were used. Additionally, the results of INOS, IL-10, and TNF-α,which were evaluated immunohistochemically, have been shown to be similar to the UW and HTK groups.

Conclusions:

AF provided conservation similar to UW and HTK in the 12-hour liver SCS process. The fact that apoptosis values are comparable to standard preservation solutions supports the success of AF in the cold storage of the liver.

Amniotic fluid minerals, trace elements, and prenatal supplement use in humans emerge as determinants of fetal growth

Amniotic fluid (AF), which is swallowed by the developing fetus, contains minerals and trace elements, but their association with fetal growth has not been explored. Our objectives were to assess (1) whether concentrations of AF minerals and trace elements were associated with changes in 5 fetal ultrasound measurements (estimated weight, bi-parietal diameter, head circumference, abdominal circumference, femur length) between 16-20 and 32-36 wks gestation and (2) whether a prenatal supplement was associated with concentrations of AF minerals and trace elements or the 5 fetal ultrasound measurements. We measured, using inductively coupled plasma-mass spectrometry (ICP-MS), 15 minerals and trace elements (aluminum, arsenic, calcium, chromium, copper, iron, lead, magnesium, nickel, potassium, rubidium, selenium, silver strontium, zinc) in amniotic fluid collected from 176 pregnant women undergoing age-related amniocentesis for genetic testing (15.7 ± 1.1 wks). AF mineral concentrations, prenatal supplement use, and determinants of ultrasound measurements during early and late pregnancy were used in models to assess their impact on change in fetal ultrasound measurements. Positive associations were identified for change in bi-parietal diameter with AF calcium, for change in head circumference with AF copper and nickel, and for change in femur length with AF selenium. Arsenic was negatively associated with estimated fetal weight, and this relationship was modified by prenatal supplement use. Additionally, AF chromium concentrations were lower in women taking prenatal supplements. In conclusion, AF minerals were associated with fetal ultrasound indices, supporting a biological role for calcium, copper, nickel and selenium in promoting in-utero fetal growth. Evidence of a mineral-vitamin interaction between arsenic and folic acid in prenatal supplements and mineral-mineral interaction between iron and chromium would suggest that attention be paid to mineral and trace element formulation of prenatal supplements.

Placental protein 14 as a potential biomarker for diagnosis of preterm premature rupture of membranes

Premature rupture of membranes (PROM) is a common pregnancy complication that frequently results in maternal and perinatal morbidity. The present methods for diagnosing PROM do not satisfy clinical requirements. The present study aimed to examine the proteome profile of amniotic fluid (AF) and maternal plasma, screen unique proteins in AF, and evaluate their diagnostic value for diagnosing PROM. The proteome profiles of AF and maternal plasma were examined via liquid chromatography coupled with tandem mass spectrometry-based proteomic techniques. The protein expression levels of diagnostic candidates in AF, maternal plasma and vaginal fluid were determined by ELISA analysis and Magnetic Luminex^® screening assays. The diagnostic value of potential biomarkers was evaluated using receiver operating characteristic curves. A lateral flow assay was developed based on colloidal gold immunochromatography technology. The present study identified 540 unique proteins in AF, 12 of which were chosen for further detection. The present results demonstrated that expression levels of pulmonary surfactant-associated protein B, BPI fold-containing family A member 1, zymogen granule protein 16 homolog B, EGF-containing fibulin-like extracellular matrix protein 1, keratin, type II cytoskeletal 4, keratin, type I cytoskeletal 19, placental protein 14 (PP14), insulin-like growth factor-binding protein 2, mesothelin and serpin family B member 3 were significantly higher in AF compared with in maternal plasma (P<0.01). Furthermore, PP14 was observed to have excellent diagnostic accuracy for preterm PROM (PPROM), with a respective sensitivity and specificity of 100 and 87.5% when the cutoff value was 0.008 µg/ml. The PP14-based lateral flow assay demonstrated a visual detection threshold of 0.008 µg/ml. The results from the present study suggested that PP14 may be a novel potential biomarker for PPROM, and may be developed into a lateral flow assay for bedside application to rapidly diagnose PPROM.

A comprehensive profile and inter-individual variations analysis of the human normal amniotic fluid proteome

Amniotic fluid contains large amounts of proteins produced by amnion epithelial cells, fetal tissues, fetal excretions and placental tissues; thus, it is an important potential source of biomarkers for identifying fetal pathologies. In this study, a pooled AF sample from 7 healthy volunteers was used to provide a comprehensive profile of normal human AF proteome using immunoaffinity depletion of 14 high-abundance proteins. Each individual AF sample was used to analyze inter-individual variations with iTRAQ method. As a result, a total of 2881 non-redundant proteins were identified, and 1624 proteins were quantified based on the peak intensity-based semi-quantification (iBAQ) method. Gene Ontology (GO) analysis showed that the AF proteome was enriched in extracellular region and extracellular matrix. Further function annotation showed that the top canonical pathway was axonal guidance signaling. The inter-individual variation analysis of 7 individual AF samples showed that the median inter-individual CV (Coefficient of variation) was 0.22. iBAQ quantification analysis revealed that the inter-individual variations were not correlated with protein abundance. GO analysis indicated that intracellular proteins tended to have higher CVs, and extracellular proteins tended to have lower CVs. These data will contribute to a better understanding of amniotic fluid proteomic analysis and biomarker discovery. SIGNIFICANCE: Amniotic fluid is an important potential source of biomarkers for identifying fetal pathologies. This study provided a large database for the normal human amniotic fluid proteome and analysis of inter-individual variations in amniotic fluid proteomes, which will offer a baseline reference for further AF proteomic analysis and pregnancy-related disease biomarker discovery.

The immunophenotype of amniotic fluid leukocytes in normal and complicated pregnancies

PROBLEM

The immune cellular composition of amniotic fluid is poorly understood. Herein, we determined: 1) the immunophenotype of amniotic fluid immune cells during the second and third trimester in the absence of intra-amniotic infection/inflammation; 2) whether amniotic fluid T cells and ILCs display different phenotypical characteristics to that of peripheral cells; and 3) whether the amniotic fluid immune cells are altered in women with intra-amniotic infection/inflammation.

METHOD OF STUDY

Amniotic fluid samples (n = 57) were collected from 15 to 40 weeks of gestation in women without intra-amniotic infection/inflammation. Samples from women with intra-amniotic infection/inflammation were also included (n = 9). Peripheral blood mononuclear cells from healthy adults were used as controls (n = 3). Immunophenotyping was performed using flow cytometry.

RESULTS

In the absence of intra-amniotic infection/inflammation, the amniotic fluid contained several immune cell populations between 15 and 40 weeks. Among these immune cells: (i) T cells and ILCs were greater than B cells and natural killer (NK) cells between 15 and 30 weeks; (ii) T cells were most abundant between 15 and 30 weeks; (iii) ILCs were most abundant between 15 and 20 weeks; (iv) B cells were scarce between 15 and 20 weeks; yet, they increased and were constant after 20 weeks; (v) NK cells were greater between 15 and 30 weeks than at term; (vi) ILCs expressed high levels of RORγt, CD161, and CD103 (ie, group 3 ILCs); (vii) T cells expressed high levels of RORγt; (viii) neutrophils increased as gestation progressed; and (ix) monocytes/macrophages emerged after 20 weeks and remained constant until term. All of the amniotic fluid immune cells, except ILCs, were increased in the presence of intra-amniotic infection/inflammation.

CONCLUSION

The amniotic fluid harbors a diverse immune cellular composition during normal and complicated pregnancies.

Cyanides in the environment-analysis-problems and challenges

Cyanide toxicity and their environmental impact are well known. Nevertheless, they are still used in the mining, galvanic and chemical industries. As a result of industrial activities, cyanides are released in various forms to all elements of the environment. In a natural environment, cyanide exists as cyanogenic glycosides in plants seeds. Too much consumption can cause unpleasant side effects. However, environmental tobacco smoke (ETS) is the most common source of cyanide. Live organisms have the ability to convert cyanide into less toxic compounds excreted with physiological fluids. The aim of this paper is to review the current state of knowledge on the behaviour of cyanide in the environment and its impact on the health and human life.

Bupropion therapy during pregnancy: the drug and its major metabolites in umbilical cord plasma and amniotic fluid

BACKGROUND

Bupropion is used for treatment of depression during pregnancy. However, its use as a smoking cessation aid for pregnant women is currently under evaluation.

OBJECTIVE

The aim of this opportunistic study was to investigate the transfer of bupropion and its major pharmacologically active metabolites, hydroxybupropion and threohydrobupropion, across the placenta in vivo. In addition, the concentrations of the drug and its metabolites were determined in the amniotic fluid.

STUDY DESIGN

The following samples were collected at deliveries from 22 women taking bupropion: maternal blood (n = 22), umbilical cord venous blood (n = 22), and amniotic fluid (n = 9). The concentrations of the drug and its metabolites in blood plasma and amniotic fluid were determined by means of liquid chromatography-mass spectrometry. Placental passage was calculated as a ratio of umbilical cord venous plasma to maternal plasma concentrations.

RESULTS

The levels of hydroxybupropion and threohydrobupropion in umbilical cord venous plasma were invariably lower than their corresponding concentrations in maternal plasma. The concentrations of bupropion in umbilical cord plasma were lower than in maternal plasma in the majority of the maternal-cord blood pairs. The median values of the umbilical cord venous plasma to maternal plasma ratios were: bupropion, 0.53 (interquartile range 0.35, n = 18), hydroxybupropion, 0.21 (interquartile range 0.12, n = 18), and threohydrobupropion, 0.61 (interquartile range 0.11, n = 21). In umbilical cord venous plasma, the median concentration of bupropion was 5.3 ng/mL; hydroxybupropion, 103.6 ng/mL; and threohydrobupropion, 59.6 ng/mL. Bupropion and its metabolites were detectable in the amniotic fluid but the concentrations of threohydrobupropion were higher than those in the corresponding umbilical cord venous plasma.

CONCLUSION

Bupropion and its active metabolites cross the placenta to the fetal circulation. The concentrations of hydroxybupropion and threohydrobupropion in umbilical cord venous plasma were higher than bupropion concentrations suggesting a higher fetal exposure to the metabolites than the parent drug. The higher levels of threohydrobupropion in the amniotic fluid than those in umbilical cord venous plasma suggest that enzymes involved in the metabolism of bupropion to threohydrobupropion are most likely active in the fetus. The biological consequences of fetal exposure to maternally administered bupropion and/or its active metabolites via placental transfer and recirculation of the amniotic fluid are yet to be determined.

Evaluation of two commercially available ELISA kits for the determination of melatonin concentrations in amniotic fluid throughout pregnancy

Background

The aim of the present study is to evaluate the utility of extraction versus non-extraction-based commercial melatonin ELISA kits for determining the melatonin concentration in amniotic fluid obtained in early and late pregnancy.

Methods

Pregnancy duration less than 28 weeks was defined as early and from 28 weeks until delivery as late gestation. Nine samples were obtained in early and 18 in late pregnancy. Two commercially available melatonin ELISA kits (melatonin ELISA RE54021, including methanol-based extraction and direct saliva melatonin ELISA RE 54041, not including an extraction step, both from IBL-International, Germany) were used to determine melatonin concentrations in amniotic fluid.

Results

The mean melatonin concentration in ELISAs assayed by the non-extraction was significantly lower than those assayed after extraction. Subgroup analysis showed that there was no significant difference between melatonin concentration measured by non-extraction versus extraction ELISA in early pregnancy (11.2 ± 7.4 vs. 12.2 ± 7.7, respectively, P = 0.463) but that the mean melatonin concentration in late pregnancy was significantly lower when assayed by non-extraction ELISA than when assayed by extraction ELISA (14.8 ± 9.3 vs. 145.1 ± 179.3, respectively; P < 0.001). Agreement between both measurements in late pregnancy was rather poor (r2 = 0.271, P = 0.022), as opposed to the good correlation found in early pregnancy (r2 = 0.929, P < 0.001).

Conclusions

The present study revealed that a melatonin assay without an extraction step, such as direct saliva ELISA, does not seem to be a valid method to determine the melatonin concentration of amniotic fluid, especially in late gestation.

Concentrations of Mineral in Amniotic Fluid and Their Relations to Selected Maternal and Fetal Parameters

The concentrations of various trace elements in amniotic fluid (AF) change over the course of pregnancy, with gestational age and fetus growth. The aim of the present study was to evaluate the concentrations of selected essential and toxic elements in AF and their relations to maternal and fetal parameters. The study was carried out in 39 pregnant women, aged 34.6 ± 4.7 years, between weeks 16 and 26 of gestation. Amniotic fluid samples were obtained during the standard procedure of amniocentesis in high-risk patients for chromosomal abnormalities. An inductively coupled plasma mass spectrometry (ICP-MS) technique was used to determine the levels of Al, As, Ba, Cd, Co, Cr, Cu, Mg, Mn, Ni, Sr, U, and V in AF. Body mass and blood pressure were measured in all the women. The basic parameters of fetal development were also assayed. It was found that the age of the mother, the gender of the fetus, and the week of the pregnancy may affect the concentrations of mineral in the amniotic fluid. Moreover, several significant correlations between the essential and toxic elements and maternal and fetal parameters were observed. In particular, negative and positive correlations between fetal parameters and magnesium and copper levels in AF, respectively, were seen. The present findings demonstrate the association between minerals in AF and fetal development.

More than fetal urine: enteral uptake of amniotic fluid as a major predictor for fetal growth during late gestation

The purpose of our study was to investigate the importance of amniotic fluid (AF) for fetal growth during late gestation using esophageal atresia (EA) patients as a model. In this retrospective cohort study, we compared the z-scores adapted for birth weights (BW z-scores) for each of 517 European newborns with congenital pre-gastric intestinal atresia, i.e., EA, to a European reference population. To account for the influence of the intestinal atresia on fetal growth per se, we compared adapted birth weights for each of 504 European newborns with post colonic intestinal atresia (anorectal malformation (ARM) with atresia of the anus) to the same European reference population. Analysis of the complete cohort showed (i) a significantly higher rate of small for gestational age newborns among EA compared to ARM newborns (p < 0.001) and (ii) significantly lower BW z-scores among EA compared to ARM newborns (p < 0.001). BW z-scores of EA newborns were significantly lower in term compared to preterm newborns with an inverse correlation with gestational age (GA) (Spearman correlation coefficient, r = -0.185, p < 0.001).

CONCLUSIONS

Enteral uptake of AF seems to play a pivotal role in fetal growth during late gestation.

WHAT IS KNOWN

• Peak velocity of fetal weight gain occurs at 33 weeks of gestation and continues until birth. During this period, fetal growth is mainly characterized by cellular hypertrophy. • Amniotic fluid (AF) comprises large amounts of hormones and growth regulators. What is New: • A significantly higher rate of small for gestational age and lower birth weights and z-scores are observed among newborn infants with congenital pre-gastric intestinal atresia. • These findings suggest that enteral uptake of AF is a major predictor for fetal growth during late gestation.

Evaluation of kidney injury biomarkers in rat amniotic fluid after gestational exposure to cadmium

Cadmium is a well-characterized nephrotoxic agent that is also capable of accumulating and diffusing across the placenta; however, only a few studies have addressed its effects over fetal kidneys and none of them has used a panel of sensitive and specific biomarkers for the detection of kidney injury. The goal of this study was to determine cadmium renal effects in rat fetuses by the quantification of early kidney injury biomarkers. Pregnant Wistar rats were exposed by inhalation to an isotonic saline solution or to CdCl2 solution (DDel =1.48 mg Cd kg(-1) day(-1) ) during gestational days (GD) 8-20. On GD 21, dams were euthanized and samples obtained. Kidney injury biomarkers were quantified in amniotic fluid samples and fetal kidneys were microscopically evaluated to search for histological alterations. Our results showed that cadmium exposure significantly raised albumin, osteopontin, vascular endothelial growth factor and tissue inhibitor of metalloproteinases-1 levels in amniotic fluid, whereas it decreased creatinine. Clusterin, calbindin and IFN-inducible protein 10 did not show any change. Accordingly, histological findings showed tubular damage and precipitations in the renal pelvis. In conclusion, gestational exposure to cadmium induces structural alterations in fetal renal tissue that can be detected by some kidney injury biomarkers in amniotic fluid samples. Copyright © 2016 John Wiley & Sons, Ltd.

Metal-based particles in human amniotic fluids of fetuses with normal karyotype and congenital malformation--a pilot study

This study explores the inorganic composition of amniotic fluid in healthy human fetuses and fetuses with congenital malformation with a special attention to presence of metal-based solid particles. Amniotic fluid originates from maternal blood and provides fetus mechanical protection and nutrients. In spite of this crucial role, the environmental impact on the composition of amniotic fluid remains poorly studied. The samples of human amniotic fluids were obtained by amniocentesis, including both healthy pregnancies and those with congenital malformations. The samples were analysed using several techniques, including Raman microspectroscopy, scanning electron microscopy with energy-dispersed spectrometry (SEM-EDS), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis. Several metal-based particles containing barium, titanium, iron, and other elements were detected by SEM-EDS and Raman microspectroscopy. XRD analysis detected only sodium chloride as the main component of all amniotic fluid samples. Infrared spectroscopy detected protein-like organic components. Majority of particles were in form of agglomerates up to tens of micrometres in size, consisting of mainly submicron particles. By statistical analysis (multiple correspondence analysis), it was observed that groups of healthy and diagnosed fetuses form two separate groups and therefore, qualitative differences in chemical composition may have distinct biological impact. Overall, our results suggest that metal-based nanosized pollutants penetrate into the amniotic fluid and may affect human fetuses.

Responses of Preterm Pigs to an Oral Fluid Supplement During Parenteral Nutrition

BACKGROUND

Nutrients and electrolytes in amniotic fluid swallowed by fetuses are important for growth and development. Yet, preterm infants requiring parenteral nutrition (PN) receive minimal or no oral inputs. With the limited availability of amniotic fluid, we evaluated the responses of preterm pigs receiving PN to an oral fluid supplement (OFS) based on the electrolyte and nutrient composition of amniotic fluid.

MATERIALS AND METHODS

Preterm pigs (92% of term) received a combination of PN (6 mL/kg-h) and 4 mL/kg-h of supplemental fluid as an experimental OFS (n = 9), lactated Ringer's either enterally (n = 10) or intravenously (n = 8). Outcome measures after 96 hours were weight gain, blood chemistry, organ weights, and small intestine mass and brush-border membrane carbohydrases.

RESULTS

The OFS did not improve weight gain compared with providing lactated Ringer's orally or intravenously, or increase serum urea nitrogen values, but resulted in higher serum total and low-density lipoprotein cholesterol, as well as improved glucoregulation and heavier intestines, livers, kidneys, and brains and lighter lungs.

CONCLUSIONS

Providing supplemental fluid and electrolytes during PN either intravenously or orally increases weight gain after preterm birth. An oral fluid supplement based on amniotic fluid may accelerate development and maturation of organs critical for extrauterine life after preterm birth and may enhance neurodevelopment.

Hyaluronic acid, an important factor in the wound healing properties of amniotic fluid: in vitro studies of re-epithelialisation in human skin wounds

Foetal wounds are unique in their ability to heal rapidly without forming scars. The amniotic fluid, rich in nutrients, growth factors, and hyaluronic acid, surrounds the foetus and is essential to foetal wound healing. The wound healing properties of foetal wounds may be the result of high concentrations of hyaluronic acid. This study aimed to verify that amniotic fluid induces re-epithelialisation in human skin wounds in vitro and to study whether this ability is dependent on hyaluronic acid. Standard deep dermal wounds were produced in vitro in human skin. The skin samples, with a central wound, were incubated in different culture media. Varying concentrations of amniotic fluid and amniotic fluid with added hyaluronidase were tested, and re-epithelialisation was assessed at 3, 7, and 12 days using light microscopy, after staining with haematoxylin and eosin. Amniotic fluid 50% resulted in a significantly higher (p < 0.05) grade of re-epithelialisation than Dulbecco's modified Eagle's medium and 10% amniotic fluid at all time points. When 50% amniotic fluid was compared with 10% foetal calf serum, no significant difference was found in grades of re-epithelialisation on days 3 and 12 and significantly higher grades of re-epithelialisation on day 7 (p < 0.05). Degradation of hyaluronic acid in the medium that contained 50% amniotic fluid gave significantly impaired re-epithelialisation (p < 0.05) on culture days 3 and 7. In conclusion, amniotic fluid promotes accelerated re-epithelialisation and hyaluronic acid is an important ingredient.

Modulation of the biochemical composition of amniotic and allantoic fluids as a control mechanism of feline foetal development

Amniotic fluid exerts a protective function and is an essential component for foetal development and maturation during pregnancy. However, little is known about the exact physiological functions of foetal fluids in this process as well as their biochemical composition in cats. In the present study, the biochemical composition of amniotic and allantoic fluids and maternal serum in pregnant queens was compared after performing an ovariohysterectomy. Fifteen queens were included in the study and distributed in four different groups, D(30), D(40), D(50) and D(60), according to their gestational age. Foetal fluids showed thoroughly greater concentrations of dissociate and total bilirubin, bile acids and gamma-glutamyl transferase than those of maternal serum, whereas albumin, total protein, alanine-transferase, creatine-kinase, amylase, lipase, triglycerides, cholesterol, HDL-cholesterol, and LDL-cholesterol were significantly lower, as compared to maternal serum. Other parameters like alkaline phosphatase, uric acid, creatinine, and electrolytes showed significant differences at specific stages of pregnancy, when compared to maternal serum. Lactate and cortisol significantly increased at the end of the pregnancy in foetal fluids, when compared with maternal serum. No significant differences between foetal fluids and maternal serum were observed for aspartate aminotransferase, lactate dehydrogenase, urea, phosphorus and glucose. According to our results, foetal fluids composition is not a result of simple filtration from maternal blood, the fetus being an active element involved in the production of the same and reflecting organ development and maturation.

Activation of coagulation in amniotic fluid during normal human pregnancy

INTRODUCTION

Amniotic fluid (AF) is an important medium for fetal development which exhibits high procoagulant activities; however, the role of these procoagulants during pregnancy has not been elucidated and might be associated with pregnancy complications. The current study aimed to evaluate factor X (FX) activation and its association with tissue factor (TF), tissue factor pathway inhibitor (TFPI) and coagulation activation markers in AF during normal human pregnancy.

METHODS

Activation of FX and concentration of TF, free TFPI, D-dimer and prothrombin fragments (F1+2) were evaluated in AF samples obtained for chromosome analysis from 91 women with normal pregnancy: 65 samples were taken from patients at 16-20 weeks of gestation, 9 samples were drawn at 21-30 weeks and 17 samples--after 30 weeks of gestation.

RESULTS

Activation of FX in AF significantly increased during normal pregnancy (from 65±41 to 205±80 equivalent RVV ng/mg total protein, P<0.0001). TF and TFPI levels in AF also rose with gestational age. In contrast, the AF concentration of D-dimer and F1+2, markers of coagulation activation significantly decreased when expressed per mg total protein. Levels of free TFPI correlated with TF (r=0.5, P<0.001), and were 8-fold higher than those of TF during pregnancy.

CONCLUSION

High levels of TFPI might be associated with the inhibition of procoagulant activity in amniotic fluid during normal pregnancy, which may account for the rarity of clinical amniotic fluid embolism.

Human amniotic fluid promotes retinal pigmented epithelial cells' trans-differentiation into rod photoreceptors and retinal ganglion cells

To evaluate the effect of human amniotic fluid (HAF) on retinal pigmented epithelial cells growth and trans-differentiation into retinal neurons, retinal pigmented epithelium (RPE) cells were isolated from neonatal human cadaver eye globes and cultured in Dulbecco's modified Eagle's medium-F12 supplemented with 10% fetal bovine serum (FBS). Confluent monolayer cultures were trypsinized and passaged using FBS-containing or HAF-containing media. Amniotic fluid samples were received from pregnant women in the first trimester of gestation. Cell proliferation and death enzyme-linked immunosorbent assays were performed to assess the effect of HAF on RPE cell growth. Trans-differentiation into rod photoreceptors and retinal ganglion cells was also studied using immunocytochemistry and real-time polymerase chain reaction techniques. Primary cultures of RPE cells were successfully established under FBS-containing or HAF-containing media leading to rapid cell growth and proliferation. When RPE cells were moved to in vitro culture system, they began to lose their differentiation markers such as pigmentation and RPE65 marker and trans-differentiated neural-like cells followed by spheroid colonies pertaining to stem/progenitor cells were morphologically detected. Immunocytochemistry (ICC) analysis of HAF-treated cultures showed a considerable expression of Rhodopsin gene (30% Rhodopsin-positive cells) indicating trans-differentiation of RPE cells to rod photoreceptors. Real-time polymerase chain reaction revealed an HAF-dose-dependant expression of Thy-1 gene (RGC marker) and significant promoting effect of HAF on RGCs generation. The data presented here suggest that HAF possesses invaluable stimulatory effect on RPE cells growth and trans-differentiation into retinal neurons. It can be regarded as a newly introduced enriched supplement in serum-free kinds of media used in neuro-retinal regeneration studies.

The interstitial lymphatic peritoneal mesothelium axis in portal hypertensive ascites: when in danger, go back to the sea

Portal hypertension induces a splanchnic and systemic low-grade inflammatory response that could induce the expression of three phenotypes, named ischemia-reperfusion, leukocytic, and angiogenic phenotypes.During the splanchnic expression of these phenotypes, interstitial edema, increased lymph flow, and lymphangiogenesis are produced in the gastrointestinal tract. Associated liver disease increases intestinal bacterial translocation, splanchnic lymph flow, and induces ascites and hepatorenal syndrome. Extrahepatic cholestasis in the rat allows to study the worsening of the portal hypertensive syndrome when associated with chronic liver disease. The splanchnic interstitium, the mesenteric lymphatics, and the peritoneal mesothelium seem to create an inflammatory pathway that could have a key pathophysiological relevance in the production of the portal hypertension syndrome complications. The hypothetical comparison between the ascitic and the amniotic fluids allows for translational investigation. From a phylogenetic point of view, the ancestral mechanisms for amniotic fluid production were essential for animal survival out of the aquatic environment. However, their hypothetical appearance in the cirrhotic patient is considered pathological since ultimately they lead to ascites development. But, the adult human being would take advantage of the potential beneficial effects of this “amniotic-like fluid” to manage the interstitial fluids without adverse effects when chronic liver disease aggravates.

Cell-free fetal nucleic acids in amniotic fluid

BACKGROUND

Research into cell-free fetal (cff) nucleic acids has primarily focused on maternal plasma; however, cff DNA and RNA are also detectable in other body fluids such as amniotic fluid (AF). In AF, cff DNA is present in much greater concentrations than in maternal plasma and represents a pure fetal sample uncontaminated by maternal- and trophoblast-derived nucleic acids. The aim of this review was to summarize the current knowledge on cff nucleic acids in AF and to outline future research directions.

METHODS

MEDLINE and PREMEDLINE were searched up to August 2010 for original investigations of cell-free RNA or DNA in AF. Sixteen studies were included in the review.

RESULTS

AF cff DNA represents a physiologically separate pool from cff DNA in maternal plasma. The placenta is not a major source of nucleic acids in AF. It is feasible to isolate cff nucleic acids from small volumes of discarded AF supernatant in sufficient quality and quantity to perform microarray studies and downstream applications such as pathway analysis. This 'discovery-driven approach' has resulted in new information on the pathogenesis of Down syndrome and polyhydramnios. There is otherwise a paucity of information relating to the basic biology and clinical applications of cff nucleic acids in AF.

CONCLUSIONS

AF supernatant is a valuable and widely available but under-utilized biological resource. Further studies of cff nucleic acids in AF may lead to new insights into human fetal development and ultimately new approaches to antenatal treatment of human disease.

Pathological axes of wound repair: gastrulation revisited

Post-traumatic inflammation is formed by molecular and cellular complex mechanisms whose final goal seems to be injured tissue regeneration.

In the skin -an exterior organ of the body- mechanical or thermal injury induces the expression of different inflammatory phenotypes that resemble similar phenotypes expressed during embryo development. Particularly, molecular and cellular mechanisms involved in gastrulation return. This is a developmental phase that delineates the three embryonic germ layers: ectoderm, endoderm and mesoderm. Consequently, in the post-natal wounded skin, primitive functions related with the embryonic mesoderm, i.e. amniotic and yolk sac-derived, are expressed. Neurogenesis and hematogenesis stand out among the primitive function mechanisms involved.

Interestingly, in these phases of the inflammatory response, whose molecular and cellular mechanisms are considered as traces of the early phases of the embryonic development, the mast cell, a cell that is supposedly inflammatory, plays a key role.

The correlation that can be established between the embryonic and the inflammatory events suggests that the results obtained from the research regarding both great fields of knowledge must be interchangeable to obtain the maximum advantage.