Selenium in reproductive health

The Role of Nutrition, Oxidative Stress, and Trace Elements in the Pathophysiology of Autism Spectrum Disorders

Autism spectrum disorder (ASD) is a neurodevelopmental condition characterized by deficits in social communication and interaction, alongside repetitive behaviors, and atypical sensory-motor patterns. The growing prevalence of ASD has driven substantial advancements in research aimed at understanding its etiology, preventing its onset, and mitigating its impact. This ongoing effort necessitates continuous updates to the body of knowledge and the identification of previously unexplored factors. The present study addresses this need by examining the roles of nutrition, oxidative stress, and trace elements in the pathophysiology of ASD. In this review, an overview is provided of the key dietary recommendations for individuals with ASD, including gluten-free and casein-free (GFCF) diets, ketogenic diets (KDs), and other nutritional interventions. Furthermore, it explores the involvement of oxidative stress in ASD and highlights the significance of trace elements in maintaining neuropsychiatric health. The impact of these factors on molecular and cellular mechanisms was discussed, alongside therapeutic strategies and their efficacy in managing ASD.

Morphology and Immunoexpression of Selenoproteins in Term Placenta of Alpaca (Vicugna pacos) from the Peruvian Andes

South American camelids inhabit high-altitude environments characterized by hypoxia, influencing embryonic, fetal, and placental development. This study examined the term placenta morphology of alpacas (Vicugna pacos, N = 12) and the immunoexpression of antioxidant selenoproteins (SP). We hypothesize that the placenta of alpacas, adapted to high altitudes, has characteristics with other species also adapted to altitude. Placentas were paraffin-embedded, sectioned (3-5 µm), stained with hematoxylin-eosin (H&E), Masson's trichrome, and picrosirius red, and analyzed via light and polarized light microscopy. The chorion showed simple cuboidal epithelium with binucleated cells, a subepithelial mesenchyme rich in blood capillaries (area: 124.90 ± 9.82 µm2), and type III collagen fibers. The chorionic villi measured 2740.22 ± 132.75 µm. The allantois contained a simple columnar epithelium and mesenchyme with type I collagen fibers. Immunohistochemistry localized SP-N, SP-P, Dio-3, and GPx-3 in the blood capillaries and mesenchymal tissue of the chorion but not in the allantois. These findings were compared to human and sheep placentas from different altitudes due to a lack of camelid data at low levels. The morphological features resembled adaptations to hypoxia observed in other species. This preliminary study suggests a potential role for selenoproteins in hypoxia adaptation, providing a basis for future functional studies.

Effects and Impact of Selenium on Human Health, A Review

Selenium (Se) is an essential trace element that is crucial for human health. As a key component of various enzymes and proteins, selenium primarily exerts its biological functions in the form of selenoproteins within the body. Currently, over 30 types of selenoproteins have been identified, with more than 20 of them containing selenocysteine residues. Among these, glutathione peroxidases (GPXs), thioredoxin reductases (TrxRs), and iodothyronine deiodinases (DIOs) have been widely studied. Selenium boasts numerous biological functions, including antioxidant properties, immune system enhancement, thyroid function regulation, anti-cancer effects, cardiovascular protection, reproductive capability improvement, and anti-inflammatory activity. Despite its critical importance to human health, the range between selenium's nutritional and toxic doses is very narrow. Insufficient daily selenium intake can lead to selenium deficiency, while excessive intake carries the risk of selenium toxicity. Therefore, selenium intake must be controlled within a relatively precise range. This article reviews the distribution and intake of selenium, as well as its absorption and metabolism mechanisms in the human body. It also explores the multiple biological functions and mechanisms of selenium in maintaining human health. The aim is to provide new insights and evidence for further elucidating the role of selenium and selenoproteins in health maintenance, as well as for future nutritional guidelines and public health policies.

The role of ferroptosis in environmental pollution-induced male reproductive system toxicity

This article provides a comprehensive review of the toxic effects of environmental pollution on the male reproductive system, with a particular emphasis on ferroptosis, a form of programmed cell death. Research has shown that environmental pollutants, such as heavy metals, pesticide residues, and plastic additives, can disrupt oxidative stress, increasing the production of reactive oxygen species (ROS) in germ cells. This disruption damages cellular lipids, proteins, and DNA, culminating in cell dysfunction or death. Ferroptosis, a cell death pathway closely linked to oxidative stress, is characterized by the accumulation of intracellular iron ions and elevated levels of lipid ROS. This review also explores the role of ferroptosis in male reproductive disorders, including its contributions to reduced sperm count, decreased motility, and abnormal morphology. Environmental pollutants, particularly heavy metals, can induce ferroptosis by interfering with intracellular antioxidant systems, notably the NRF2, GSH, and GPX4 pathways, accumulating toxic lipid peroxides. Furthermore, the article examines the potential interplay between ferroptosis and other forms of cell death, such as apoptosis, autophagy, pyroptosis, and necrosis, in the context of male reproductive health. The review underscores the critical need for further research into the link between environmental pollutants and male fertility, particularly focusing on ferroptosis. It advocates for targeted research efforts to mitigate the adverse effects of ferroptosis and protect reproductive health, emphasizing that a deeper understanding of these mechanisms could lead to innovative preventive strategies against environmental threats to fertility.

Robust Fluorescent Nanoprobe for Rapid Evaluation of the Selenium Supplementation Effect and Imaging

At present, an increasing number of people pay more attention to selenium-enriched food, but the quality of the selenium-enriched food varies. Therefore, there is an urgent need to develop a new tool to assess the effects of selenium supplementation in foods by rapidly detecting the levels of the metabolite selenium selenocysteine (Sec). In this work, a fluorescent nanoprobe CS-Sec was designed, synthesized, and characterized for Sec detection and imaging in living biosystems, which exhibited the advantages of good biocompatibility, excellent water solubility, high sensitivity, high selectivity, and rapid response (2.5 min) for Sec detection and imaging in vitro and in vivo and evaluation of selenium supplementation in selenium-rich foods. Specifically, CS-Sec was constructed by grafting alkyne groups on organic small-molecule fluorescent probes with azide groups on azido chitosan by click chemistry. A 2,4-dinitrophenyl ether (DNB) with a strong intramolecular charge transfer (ICT) effect was selected as a response group and fluorescence-quenching group, which had excellent chemical specificity toward Sec. In addition, CS-Sec has high selectivity and sensitivity toward Sec over other analytes, and an excellent limit of detection (LOD) is as low as 15 nM. Impressively, CS-Sec has been successfully used to detect and image the concentration of Sec in living HepG2 cells and mouse models with exciting results, indicating that the newly constructed CS-Sec can provide a robust molecule tool for the rapid evaluation of the selenium supplementation effect and imaging in the future.

Enhancing of Rabbit Sperm Cryopreservation with Antioxidants Mito-Tempo and Berberine

Cryopreservation plays a critical role in animal breeding and the conservation of endangered species, but it often compromises sperm characteristics such as morphology, motility, and viability due to oxidative stress. This study explores the antioxidative effect of Mito-Tempo (MT) and Berberine (BER) to enhance post-thaw sperm quality in rabbits. Pooled rabbit sperm samples were supplemented with different concentrations (0.0, 0.5, 5, 10, 50 µmol/L) of MT and BER. Sperm motility was evaluated using computer-assisted semen analysis, while viability, apoptosis, reactive oxygen species (ROS) levels, acrosome integrity, and mitochondrial function were assessed through flow cytometry. The results revealed that MT at 5 and 10 µmol/L and BER at 10 µmol/L significantly improved total and progressive motility, mitochondrial activity, and sperm viability compared to the control group. Furthermore, 10 µmol/L BER enhanced acrosome integrity, while both 5 µmol/L MT and 10 µmol/L BER effectively reduced ROS levels and apoptosis. This study is the first to demonstrate the protective effects of MT and BER on rabbit sperm during cryopreservation. By mitigating oxidative stress and reducing apoptosis, these antioxidants markedly improved post-thaw sperm quality, positioning MT and BER as promising agents for improving sperm cryosurvival.

Erythrocyte Selenium as a Potential Key Indicator for Selenium Supplementation in Low-Selenium Populations: A Selenium Supplementation Study Based on Wistar Rats

BACKGROUND

Selenium (Se) is an essential trace element for maintaining human health, with significant antioxidant and immunoregulatory functions. Inadequate Se intake may be associated with Keshan disease, Kashin-Beck disease, and hypothyroidism. However, effective indicators for scientifically guiding Se supplementation in Se-deficient populations are still lacking.

OBJECTIVES

This study aims to explore the dynamic distribution of Se across various nutritional biomarkers and major organs in rats through a Se supplementation experiment, as well as the pairwise correlations between them, in order to identify reliable nutritional indicators for evaluating Se levels in the body.

METHODS

Se levels in hair, blood, and major tissues and organs were determined by atomic fluorescence spectrometry, and glutathione peroxidase (GSH-Px) levels were measured using an ELISA.

RESULTS

Se supplementation significantly increased Se levels in rat blood, hair, and major organs, as well as GSH-Px levels in blood. Se primarily accumulated in the liver and kidneys, followed by myocardium, spleen, and muscles. Serum and plasma Se were found to be the best indicators of short-term Se intake, while erythrocyte Se levels showed a stronger correlation with Se levels in tissues and organs, making it a better marker for assessing long-term Se nutritional status compared to hair Se.

CONCLUSIONS

This study demonstrates the potential of erythrocyte Se levels as an indicator for evaluating long-term Se nutritional status, providing scientific evidence for Se nutritional assessments.

Palliative Effect of Combined Application of Zinc and Selenium on Reproductive Injury Induced by Tripterygium Glycosides in Male Rats

The long-term use of tripterygium glycosides (TG) can lead to male reproductive damage. Research indicates that zinc and selenium exhibit a synergistic effect in the male reproductive system, with the combined preparation demonstrating superior therapeutic effects compared to individual preparations. The purpose of this study was to explore the specific mechanism by which zinc and selenium mitigate reproductive toxicity induced by TG in male rats. Rats were randomly assigned to three groups: control group (C group), model group (M group, receiving TG at 30 mg/kg/day), and model + zinc + selenium group (ZS group). The ZS group was also given TG gavage for the first 4 weeks. Starting from the fifth week until the conclusion of the eighth week, the ZS group received an additional protective treatment of 10 mg/kg/day Zn and 0.1 mg/kg/day Se 4 h after TG administration. Following euthanasia, blood samples, rat testis, and epididymis tissues were collected for further experiments. Combined zinc-selenium treatment corrects the imbalance of zinc-selenium homeostasis in testicular tissue induced by TG. This is achieved by upregulating the expression of metal transcription factor (MTF1) and zinc transporters ZIP8 and ZIP14 and downregulating the expression of ZnT10. Improvement of zinc and selenium homeostasis enhanced the expression of zinc-containing enzymes (ADH, LDH, and ALP) and selenoproteins (GPx1 and SELENOP) in the testis. At the same time, zinc and selenium mitigate TG-induced reproductive damage by promoting the activity of antioxidant enzymes and upregulating the expression of proteins associated with the oxidative stress pathway, including Nrf2, Keap1, HO-1, PI3K, and p-AKT.

Genome-wide association study of maternal plasma metabolites during pregnancy

Metabolites are key indicators of health and therapeutic targets, but their genetic underpinnings during pregnancy-a critical period for human reproduction-are largely unexplored. Using genetic data from non-invasive prenatal testing, we performed a genome-wide association study on 84 metabolites, including 37 amino acids, 24 elements, 13 hormones, and 10 vitamins, involving 34,394 pregnant Chinese women, with sample sizes ranging from 6,394 to 13,392 for specific metabolites. We identified 53 metabolite-gene associations, 23 of which are novel. Significant differences in genetic effects between pregnant and non-pregnant women were observed for 16.7%-100% of these associations, indicating gene-environment interactions. Additionally, 50.94% of genetic associations exhibited pleiotropy among metabolites and between six metabolites and eight pregnancy phenotypes. Mendelian randomization revealed potential causal relationships between seven maternal metabolites and 15 human traits and diseases. These findings provide new insights into the genetic basis of maternal plasma metabolites during pregnancy.

Fast Intramolecular Thiol-Activated Arylselenoamides Provide Access to Triggered, Fluorogenic H2Se Donors

H2Se is the precursor for the biosynthesis of selenocompounds and is a potential gasotransmitter. Chemical tools for H2Se delivery and detection are important for Se-related biology research. Key challenges in the field include developing compound platforms that are triggered to release H2Se under various stimuli and developing fluorogenic donors that allow for real-time tracking of H2Se delivery. Here we report a new general platform for triggered H2Se donors based on controllable deprotection of a thiol, which can quickly activate an intramolecular arylselenoamide (t1/2 < 1 min) to release H2Se efficiently. Furthermore, we leverage this platform to develop the first examples of fluorogenic H2Se donors, which can be used to monitor H2Se release by fluorescence in real time. We anticipate that the well-defined donation chemistries will significantly advance the development of H2Se donors and stimulate further in-depth studies of H2Se biomedicine.

A comprehensive review on potential role of selenium, selenoproteins and selenium nanoparticles in male fertility

Selenium (Se), a component of selenoproteins and selenocompounds in the human body, is crucial for the development of male reproductive organs, DNA synthesis, thyroid hormone, metabolism, and defence against infections and oxidative damage. In the testis, it must exceed a desirable level since either a shortage or an overabundance causes aberrant growth. The antioxidant properties of selenium are essential for preserving human reproductive health. Selenoproteins, which have important structural and enzymatic properties, control the biological activities of Se primarily. These proteins specifically have a role in metabolism and a variety of cellular processes, such as the control of selenium transport, thyroid hormone metabolism, immunity, and redox balance. Selenium nanoparticles (SeNPs) are less hazardous than selenium-based inorganic and organic materials. Upon being functionalized with active targeting ligands, they are both biocompatible and capable of efficiently delivering combinations of payloads to particular cells. In this review, we discuss briefly the chemistry, structure and functions of selenium and milestones of selenium and selenoproteins. Next we discuss the various factors influences male infertility, biological functions of selenium and selenoproteins, and role of selenium and selenoproteins in spermatogenesis and male fertility. Furthermore, we discuss the molecular mechanism of selenium transport and protective effects of selenium on oxidative stress, apoptosis and inflammation. We also highlight critical contribution of selenium nanoparticles on male fertility and spermatogenesis. Finally ends with conclusion and future perspectives.

Current understanding of essential trace elements in intrahepatic cholestasis of pregnancy

Trace elements are important components in the body and have fundamental roles in maintaining a healthy and balanced pregnancy process. Either deficiency or excess of trace elements, including selenium, iron, zinc, copper, and magnesium can lead to pregnancy complications. As a rare disorder during pregnancy of unknown aetiology, intrahepatic cholestasis of pregnancy (ICP) poses a significant risk to the fetus of perinatal mortality. ICP is a multifactorial complication of which the pathogenesis is still an enigma. Epidemiological studies have demonstrated the association of ICP with some trace elements. Evidence from retrospective studies in humans further revealed the possible contributing roles of trace elements in the pathogenesis of ICP. The published literature on the association of trace elements with ICP was reviewed. Recent advances in molecular biological techniques from animal studies have helped to elucidate the possible mechanisms by how these trace elements function in regulating oxidative reactions, inflammatory reactions and immune balance in the maternal-fetal interface, as well as the influence on hepato-intestinal circulation of bile acid. The scenario regarding the role of trace elements in the pathogenesis of ICP is still developing. The administration or depletion of these trace elements may have promising effects in alleviating the symptoms and improving the pregnancy outcomes of ICP.

Serum anti-mullerian hormone, sex hormone, and nutrient levels in reproductive age women with celiac disease

PURPOSE

This study aimed to investigate the changes in serum Anti-Müllerian Hormone (AMH) levels, sex hormone levels, follicle-stimulating hormone (FSH)/luteinizing hormone (LH) ratio in patients with celiac disease (CeD), and their correlation with clinical characteristics and nutrient levels.

METHODS

This cross-sectional study collected clinical and biochemical data from a total of 67 females diagnosed with CeD and 67 healthy females within the reproductive age range of 18-44 years. The study was conducted at a tertiary hospital between September 2016 and January 2024. Both groups underwent comprehensive clinical and laboratory assessments. Serum levels of AMH and sex hormones were quantified using chemiluminescence immunoassay, and their associations with CeD clinical features and nutrient levels were thoroughly analyzed.

RESULTS

The study included 67 patients and 67 controls with a mean age of 36.7±7.6 years. No statistically significant differences were found between the two groups in mean age, BMI, FSH, LH, E2, P levels, FSH/LH, menstrual irregularities, abortions history, parity, and gravidity (all P>0.05). However, AMH, T, FER, FA, Zn, and Se levels were significantly lower, and PRL levels were higher in the CeD group (all P<0.05). Spearman's correlation analysis showed that AMH levels were negatively correlated with age, tTG level, disease duration, and Marsh grading (P<0.05).

CONCLUSIONS

This study highlights the association between impaired ovarian function in CeD patients and disease severity and nutrient levels. Early detection and intervention for ovarian function abnormalities are imperative to enhance fertility potential in CeD patients.

Selenium Intake and Postnatal Depression-A Short Review

Postnatal depression is a common and severe complication of childbirth. It is an important public health problem with significant implications for both mothers and children. The exact mechanisms underlying and the factors influencing the occurrence of postnatal depression remain unclear. The literature suggests that certain dietary deficiencies during pregnancy and the postnatal period may contribute to a greater risk of maternal depression. This review focuses on the role of selenium in postnatal depression. It collects evidence from published interventional and observational studies investigating the relationship between selenium intake during the antenatal and postnatal periods and the mental status of postpartum women and summarises information about biological mechanisms that may underlie the association between selenium status and postnatal depression. The review includes studies identified through electronic searches of Medline (via PubMed) and Google Scholar databases until December 2023. Despite the small number of relevant studies and their potential methodological limitations, the findings suggest that optimizing selenium status may support the prevention and treatment of postnatal depression. Further longitudinal and interventional studies are necessary to confirm the clinical significance of these effects.

Prenatal metal concentrations and physical abnormalities in the Japan Environment and Children's Study

BACKGROUND

The association between prenatal metal exposure and congenital anomalies is unclear. We aimed to examine the association between exposure to cadmium, lead, mercury, selenium, and manganese and physical abnormalities.

METHODS

Data from 89,887 pregnant women with singleton pregnancies who participated in the Japan Environment and Children's Study (JECS) were used. The correlation between maternal blood metal concentrations and physical abnormalities during the second or third trimester was investigated using logistic regression models. Physical anomalies included those observed at birth or at 1 month, primarily from ICD-10 Chapter 17, particularly congenital anomalies associated with environmental factors (e.g., hypospadias, cryptorchidism, cleft lip and palate, digestive tract atresia, congenital heart disease, and chromosomal abnormalities) and minor abnormalities.

RESULTS

After adjusting for covariates, the OR (95% CIs) of physical abnormalities for a one-unit rise in Mn concentrations in all individuals were 1.26 (1.08, 1.48). The OR (95% CIs) of physical abnormalities in the 4th quartile (≥18.7 ng/g) were 1.06 (1.01, 1.13) (p-value for the trend = 0.034) compared with those in the 1st quartile (≤12.5 ng/g).

CONCLUSION

In Japan, maternal blood Mn concentrations above threshold during pregnancy may slightly increase the incidence of physical abnormalities.

IMPACT

Physical abnormalities (including minor anomalies and congenital anomalies) are associated with prenatal manganese concentrations. They are not associated with cadmium, lead, mercury, and selenium concentrations.

Higher Concentrations of Essential Trace Elements in Women Undergoing IVF May Be Associated with Poor Reproductive Outcomes Following Single Euploid Embryo Transfer

Essential trace elements are micronutrients whose deficiency has been associated with altered fertility and/or adverse pregnancy outcomes, while surplus may be toxic. The concentrations of eight essential trace elements were measured using inductively coupled mass spectrometry (ICP-MS) and assessed with respect to clinical in vitro fertilization (IVF) outcomes in a population of 51 women undergoing IVF with intracytoplasmic sperm injection (ICSI), pre-implantation genetic screening for aneuploidy (PGT-A), and single frozen euploid embryo transfer (SET/FET). Specifically, copper (Cu), zinc (Zn), molybdenum, selenium, lithium, iron, chromium, and manganese were quantified in follicular fluid and whole blood collected the day of vaginal oocyte retrieval (VOR) and in urine collected the day of VOR and embryo transfer. We found that the whole blood Cu/Zn ratio was significantly associated with superior responses to ovarian stimulation. Conversely, the whole blood zinc and selenium concentrations were significantly associated with poor ovarian response outcomes. Higher levels of whole blood zinc and selenium, urinary selenium, lithium, and iron had significant negative associations with embryologic outcomes following IVF. Regarding clinical IVF outcomes, higher urinary molybdenum concentrations the day of VOR were associated with significantly lower odds of implantation and live birth, while higher urinary Cu/Mo ratios on the day of VOR were associated with significantly higher odds of implantation, clinical pregnancy, and live birth. Our results suggest that essential trace element levels may directly influence the IVF outcomes of Spanish patients, with selenium and molybdenum exerting negative effects and copper-related ratios exerting positive effects. Additional studies are warranted to confirm these relationships in other human populations.

Trace and essential elements as vital components to improve the performance of the male reproductive system: Implications in cell signaling pathways

Successful male fertilization requires the main processes such as normal spermatogenesis, sperm capacitation, hyperactivation, and acrosome reaction. The progress of these processes depends on some endogenous and exogenous factors. So, the optimal level of ions and essential and rare elements such as selenium, zinc, copper, iron, manganese, calcium, and so on in various types of cells of the reproductive system could affect conception and male fertility rates. The function of trace elements in the male reproductive system could be exerted through some cellular and molecular processes, such as the management of active oxygen species, involvement in the action of membrane channels, regulation of enzyme activity, regulation of gene expression and hormone levels, and modulation of signaling cascades. In this review, we aim to summarize the available evidence on the role of trace elements in improving male reproductive performance. Also, special attention is paid to the cellular aspects and the involved molecular signaling cascades.

Effects of Selenium Supplementation on the Indices of Disease Activity, Inflammation and Oxidative Stress in Patients with Rheumatoid Arthritis: a Randomized Clinical Trial

The aim of study was to evaluate the effect of selenium supplementation on disease activity, inflammation, and oxidative stress in patients with rheumatoid arthritis (RA). This study was a randomized double-blind placebo-controlled trial on 59 patients with RA. Participants were randomly divided to receive 200 μg/day of selenium or a placebo for 12 weeks. The disease activity score (DAS.CRP and DAS.ESR), erythrocyte sedimentation rate (ESR), serum levels of C-reactive protein (CRP), fasting blood glucose, lipids, antibodies to cyclic citrullinated protein (anti-CCP), nitric oxide, glutathione, and total antioxidant capacity were assessed. The mean of DAS.CRP and DAS.ESR decreased significantly within both study groups after the intervention. However, the between-group comparisons revealed no significant differences. The CRP levels decreased significantly in the selenium group, and this decrease was near the significance level compared to the placebo (P = 0.05). However, after adjusting for baseline values, the observed difference between groups did not remain significant. In addition, the values of ESR and anti-CCP decreased significantly within the selenium group. Although, between-group comparison did not statistically significant, the change in ESR and anti-CCP in the selenium group was small clinically relevant compared to the placebo [the effect size (95% CI) for ESR: 0.38 (- 0.14, 0.89), and for anti-CCP: 0.32 (- 0.2, 0.83)]. Our study showed that selenium caused a small clinically relevant improvement in some RA biomarkers such as ESR and anti-CCP. Future studies that evaluate the effects of novel forms of supplements such as selenium nanoparticles on the clinical symptoms and biomarkers of RA are suggested. Trial Registration: At www.irct.ir as IRCT20190924044869N1 on 2020-06-14.

Minerals and the Menstrual Cycle: Impacts on Ovulation and Endometrial Health

The role of minerals in female fertility, particularly in relation to the menstrual cycle, presents a complex area of study that underscores the interplay between nutrition and reproductive health. This narrative review aims to elucidate the impacts of minerals on key aspects of the reproductive system: hormonal regulation, ovarian function and ovulation, endometrial health, and oxidative stress. Despite the attention given to specific micronutrients in relation to reproductive disorders, there is a noticeable absence of a comprehensive review focusing on the impact of minerals throughout the menstrual cycle on female fertility. This narrative review aims to address this gap by examining the influence of minerals on reproductive health. Each mineral's contribution is explored in detail to provide a clearer picture of its importance in supporting female fertility. This comprehensive analysis not only enhances our knowledge of reproductive health but also offers clinicians valuable insights into potential therapeutic strategies and the recommended intake of minerals to promote female reproductive well-being, considering the menstrual cycle. This review stands as the first to offer such a detailed examination of minerals in the context of the menstrual cycle, aiming to elevate the understanding of their critical role in female fertility and reproductive health.

The effect of selenium on the proliferation of bovine endometrial epithelial cells in a lipopolysaccharide-induced damage model

BACKGROUND

Endometritis is a common bovine postpartum disease. Rapid endometrial repair is beneficial for forming natural defense barriers and lets cows enter the next breeding cycle as soon as possible. Selenium (Se) is an essential trace element closely related to growth and development in animals. This study aims to observe the effect of Se on the proliferation of bovine endometrial epithelial cells (BEECs) induced by lipopolysaccharide (LPS) and to elucidate the possible underlying mechanism.

RESULTS

In this study, we developed a BEECs damage model using LPS. Flow cytometry, cell scratch test and EdU proliferation assay were used to evaluate the cell cycle, migration and proliferation. The mRNA transcriptions of growth factors were detected by quantitative reverse transcription-polymerase chain reaction. The activation of the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) and Wnt/β-catenin pathways were detected by Western blotting and immunofluorescence. The results showed that the cell viability and BCL-2/BAX protein ratio were significantly decreased, and the cell apoptosis rate was significantly increased in the LPS group. Compared with the LPS group, Se promoted cell cycle progression, increased cell migration and proliferation, and significantly increased the gene expressions of TGFB1, TGFB3 and VEGFA. Se decreased the BCL-2/BAX protein ratio, promoted β-catenin translocation from the cytoplasm to the nucleus and activated the Wnt/β-catenin and PI3K/AKT signaling pathways inhibited by LPS.

CONCLUSIONS

In conclusion, Se can attenuate LPS-induced damage to BEECs and promote cell proliferation and migration in vitro by enhancing growth factors gene expression and activating the PI3K/AKT and Wnt/β-catenin signaling pathways.

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.

Parental treatment with selenium protects Caenorhabditis elegans and their offspring against the reproductive toxicity of mercury

Mercury (Hg) is one of the major pollutants in the environment, which requires effective countermeasures to manage its risk to both human health and the ecosystem. The antagonistic effect of selenium (Se) against methyl mercury (MeHg) and HgCl2 was evaluated using parent and offspring Caenorhabditis elegans (C. elegans) in this study. Through designated acute exposure of 24 h, our results showed that both MeHg and HgCl2 induced dose-dependent reproductive toxicity, including increased germ cell apoptosis, decrease in the number of oocytes, brood size, and sperm activation. The increased germ cell apoptosis was even higher in F1 and F2 generations, but returned to control level in F3 generation. Pretreatment with Se significantly suppressed the reproductive toxicity caused by Hg in both parental worms and their offspring, but had little influence on Hg accumulation. The protective role of Se was found closely related to the chemical forms of Hg: mtl-1 and mtl-2 genes participated in reducing the toxicity of HgCl2, while the gst-4 gene was involved in the reduced toxicity of MeHg. The formation of Se-Hg complex and the antioxidant function of Se were considered as possible antagonistic mechanisms. Our data indicated that pretreatment with Se could effectively protect C. elegans and their offspring against the reproductive toxicity of Hg in different chemical forms, which provided a reference for the prevention of Hg poisoning and essential information for better understanding the detoxification potential of Se on heavy metals.

Emerging evidence on selenoneine and its public health relevance in coastal populations: a review and case study of dietary Se among Inuit populations in the Canadian Arctic

Selenium is an essential mineral yet both deficiency and excess are associated with adverse health effects. Dietary intake of Se in humans varies greatly between populations due to food availability, dietary preferences, and local geological and ecosystem processes impacting Se accumulation into agricultural products and animal populations. We argue there is a need to evaluate and reconsider the relevance of public health recommendations on Se given recent evidence, including the metabolic pathways and health implications of Se. This argument is particularly pertinent for Inuit populations in Northern Canada, who often exceed dietary tolerable upper intake levels and exhibit very high whole blood Se concentrations due to their dependence on local country foods high in the newly discovered Se compound, selenoneine. Since selenoneine appears to have lower toxicity compared to other Se species and does not contribute to the circulating pools of Se for selenoprotein synthesis, we argue that total dietary Se or total Se in plasma or whole blood are poor indicators of Se adequacy for human health in these populations. Overall, this review provides an overview of the current evidence of Se speciation, deficiency, adequacy, and excess and implications for human health and dietary recommendations, with particular reference to Inuit populations in the Canadian Arctic and other coastal populations consuming marine foods.

Selenium mitigates methotrexate-induced testicular injury: Insights from male NMRI mice model

BACKGROUND AND AIM

Chemotherapy, particularly with methotrexate (MTX), often elicits testicular toxicity, leading to impaired spermatogenesis and hormone imbalances. This study aimed to investigate the potential protective effects of selenium (Se) against MTX-induced testicular injury.

MATERIALS AND METHODS

Male mice were divided into control, MTX, Se, and MTX + Se groups. Histopathological examination involved the preparation of testicular tissue sections using the Johnsen's tubular biopsy score (JTBS) for spermatogenesis evaluation. Biochemical tests included the assessment of testosterone, malondialdehyde (MDA), luteinizing hormone (LH), and follicle-stimulating hormone (FSH) levels. Real-time quantitative polymerase chain reaction (RT-qPCR) was employed to analyze the expression of caspase 3 (casp3), tumor protein 53 (p53), B-cell lymphoma 2 (Bcl2), and Bcl2-associated X protein (Bax) genes. Statistical analysis was performed using ANOVA and Tukey's tests (p < .05).

RESULTS

Histopathological analysis revealed significant testicular damage in the MTX group, with decreased spermatogenesis and Leydig cell count, while Se administration mitigated these effects, preserving the structural integrity of the reproductive epithelium. Biochemical analysis demonstrated that MTX led to elevated malondialdehyde (MDA) levels and reduced testosterone, LH, and FSH levels, suggesting oxidative stress and Leydig cell dysfunction. Gene expression analysis indicated that MTX upregulated proapoptotic genes (casp3, p53, and bax) while downregulating the antiapoptotic Bcl2 gene. In contrast, Se treatment reversed these trends, highlighting its potential antiapoptotic properties.

CONCLUSION

Our findings underscore the potential of Se as a therapeutic agent to mitigate the reproductive toxicity associated with MTX-induced testicular injury. Se exerts protective effects by regulating oxidative stress, preserving hormone balance, and modulating apoptotic pathways. These results suggest that Se supplementation could be a promising strategy to alleviate chemotherapy-induced testicular damage and preserve male fertility.

Selenium Content in the Gonads of Healthy Cats (Felis catus) and Cats with Impaired Homeostasis from the Warsaw Area (Poland)

The aim of the present study was to evaluate selenium content in the gonads of healthy cats and those with impaired homeostasis with the use of fluorescence spectroscopy. Higher concentrations of selenium were found in the gonads of the male domestic cats studied. The average content of this element in the testes of healthy males was: 0.59 mg·kg-1 while 0.47 mg·kg-1 wet weight was recorded in the ovaries of females. In the case of individuals with impaired homeostasis, higher values of selenium were found in the ovaries of obese females (0.40 mg·kg-1), while in the case of females with diagnosed malignancy of the mammary gland, the average values were lower and amounted to 0.31 mg·kg-1 wet weight of tissue. On the basis of statistical analysis, significant differences were found according to sex, age, and disturbed homeostasis of the individuals studied. An association was found between low Se in the gonads and obesity, as well as the presence of mammary gland neoplastic lesions. In addition, Se content was found to decrease with age in females, which can reduce resistance to oxidative stress.

An Overview of Reactive Oxygen Species Damage Occurring during In Vitro Bovine Oocyte and Embryo Development and the Efficacy of Antioxidant Use to Limit These Adverse Effects

The in vitro production (IVP) of bovine embryos has gained popularity worldwide and in recent years and its use for producing embryos from genetically elite heifers and cows has surpassed the use of conventional superovulation-based embryo production schemes. There are, however, several issues with the IVP of embryos that remain unresolved. One limitation of special concern is the low efficiency of the IVP of embryos. Exposure to reactive oxygen species (ROS) is one reason why the production of embryos with IVP is diminished. These highly reactive molecules are generated in small amounts through normal cellular metabolism, but their abundances increase in embryo culture because of oocyte and embryo exposure to temperature fluctuations, light exposure, pH changes, atmospheric oxygen tension, suboptimal culture media formulations, and cryopreservation. When uncontrolled, ROS produce detrimental effects on the structure and function of genomic and mitochondrial DNA, alter DNA methylation, increase lipid membrane damage, and modify protein activity. Several intrinsic enzymatic pathways control ROS abundance and damage, and antioxidants react with and reduce the reactive potential of ROS. This review will focus on exploring the efficiency of supplementing several of these antioxidant molecules on oocyte maturation, sperm viability, fertilization, and embryo culture.

Studies on the ameliorative potential of dietary supplemented different dose of selenium on doxorubicin-induced ovarian damage in rat

Doxorubicin (Dox) may induce loss of follicles, resulting in the depletion of ovarian reserve and consequent premature ovarian failure. Selenium (Se) is an oligoelement with fundamental biological features and is among the most common chemical inhibitor compounds. The present study describes the curative effects of dietary supplementation with different Se doses on Dox-induced ovarian damage in rats. In this study, 64 adult female Wistar rats were randomly separated into eight groups: Control group, Dox group (5 mg/kg intraperitoneal [i.p.]), low-dose Se (0.5 mg/kg i.p.), middle dose Se (1 mg/kg i.p.), high dose (Se 2 mg/kg i.p.), Dox + low-dose Se group (0.5 mg/kg i.p.), Dox + middle dose Se (1 mg/kg i.p.), and Dox + high-dose Se group (2 mg/kg i.p.). After the experiment, ovarian follicles were counted, and Antimüllerian hormone, interleukin 1 beta, tumor necrosis factor alpha, and caspase-3 expression were determined. Levels of malondialdehyde, superoxide dismutase, catalase, and glutathione peroxidase were biochemically measured in ovarian tissue. Dox caused ovarian injury, as evidenced by significant changes in ovarian markers, histological abnormalities, and the debilitation of antioxidant defense mechanisms. Furthermore, Dox therapy significantly changed the expression of inflammatory and apoptotic markers. Dox + 1 mg Se with various saturations was studied, and this study demonstrated both histopathological and follicular reserve and more protective features. 1 mg Se pretreatment improved Dox-induced ovarian toxicity through alleviating the antioxidant mechanism, decreasing inflammation and apoptosis, and restoring ovarian architecture. As a result, our findings indicate that 1 mg Se is a promising therapeutic agent for the prevention of ovarian damage associated with Dox.

Development of trisubstituted thiophene-3-arboxamide selenide derivatives as novel EGFR kinase inhibitors with cytotoxic activity

Overexpression of EGFR is one of the eminent oncogenic drivers detected in the development of several human cancers. The increasing incidences of mutation-based resistance in the tyrosine kinase domain call upon the need for the development of a newer class of small-molecule TK inhibitors. Accordingly, a new series of symmetrical trisubstituted thiophene-3-carboxamide selenide derivatives was developed via the hybridization of complementary pharmacophores. Most of the compounds showed a modest to excellent antiproliferative action at 20 μM concentration. The utmost antiproliferative activity was portrayed by compound 16e on the selected cancer cell lines with IC50 < 9 μM, the lowest being 3.20 ± 0.12 μM in the HCT116 cell line. Further, it also displayed an impressive EGFR kinase inhibition with an IC50 value of 94.44 ± 2.22 nM concentration. As a corollary of the reported EGFR inhibition, the nature, energy, and stability of the binding interactions were contemplated via in silico studies.

Serum Cu, Zn and IL-1β Levels May Predict Fetal Miscarriage Risk After IVF Cycles: A Nested Case-Control Study

To explore the association between serum-related indicators (levels of inflammatory cytokines and essential trace elements) and miscarriage risk among infertile women undergoing assisted reproductive techniques (ART) on the 14th day after embryo transfer, and to develop and establish a multivariable algorithm model that might predict pregnancy outcome. According to a nested case-control study design, a total of 100 miscarriage cases and 100 live birth controls were included in this study, and women in both groups were infertile and have underwent in vitro fertilization (IVF). Pregnancy tests were performed and serum levels of five essential trace elements (vanadium (V), copper (Cu), zinc (Zn), selenium (Se) and molybdenum (Mo)) and five inflammatory cytokines (interleukin-1β (IL-1β), IL-6, IL-8, IL-10 and tumor necrosis factor-α (TNF-α)) of the participants were measured on the 14th day after embryo transfer. The serum levels of five inflammatory cytokines were determined by multiple magnetic bead enzyme immunity analyzer; and the serum concentrations of five elements were determined simultaneously by inductively coupled plasma‒mass spectrometry (ICP ‒ MS). The logistic regression was used to evaluate the relationship between these serum indices and miscarriage risk among women undergoing ART, and a predictive model of pregnancy outcome based on these indices was established. The levels of IL-10, IL-1β and TNF-α of infertile women in the live birth group were significantly higher than those in the miscarriage group (p = 0.009, p < 0.001, p = 0.006), and the levels of V, Cu, Zn and Se of infertile women in the live birth group were also significantly higher than those in the miscarriage group (all p < 0.001). Through logistic regression analyses, we found that serum levels of IL-1β, TNF-α, V, Cu, Zn and Se were significantly and negatively associated with miscarriage risk. Different combination prediction models were generated according to the results of logistic regression analyses, and the combination of IL-1β, Cu and Zn had the best prediction performance. The area under the curve (AUC) was 0.776, the sensitivity of the model was 60% and the specificity was 84%. In conclusion, the serum-related indicators of women undergoing ART on the 14th day after embryo transfer, including the inflammatory cytokines such as IL-1β and TNF-α and the essential trace metal elements such as V, Cu, Zn and Se, were negatively correlated with miscarriage risk. A multivariate algorithm model to predict pregnancy outcome among women undergoing ART was established, which showed that IL-1β, Cu and Zn might synergistically predict pregnancy outcome.

Serum selenium, selenoprotein P, and glutathione peroxidase 3 during early and late pregnancy in association with gestational diabetes mellitus: Prospective Odense Child Cohort

BACKGROUND

Diet is an important modifiable risk factor for gestational diabetes mellitus (GDM) and its related complications; however, the role of essential micronutrients such as selenium (Se), particularly in populations with low Se intake, is inconclusive.

OBJECTIVES

The aim was to investigate the association of 3 established biomarkers of Se status with GDM, gestational glucose metabolism, and large for gestational-age offspring.

METHODS

This study included 1346 pregnant females with 2294 serum samples from the prospective, population-based Odense Child Cohort study, Denmark. Serum Se, selenoprotein P (SELENOP) concentrations, and glutathione peroxidase 3 (GPX3) activity were measured in early and late pregnancy, and fasting glucose and insulin assessments in late pregnancy. Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) was calculated, and the GDM definition was according to the WHO 2013 threshold of fasting venous plasma glucose of ≥5.1 mmol/L. A subcohort underwent an oral glucose tolerance test. Regression models adjusted for various confounders quantified dose-dependent associations.

RESULTS

Se and SELENOP declined during pregnancy. There were dose-dependent inverse associations of early GPX3 with late pregnancy GDM (WHO 2013), fasting glucose, insulin, HOMA-IR, and 2 h glucose. The odds ratio (OR) of GDM was 0.33 (95% CI: 0.16, 0.65) for 1 log-scale-increment in early GPX3 activity. Late pregnancy GPX3 and SELENOP were inversely associated with GDM and HOMA-IR; the OR of GDM was 0.21 (95% CI: 0.12, 0.38) and 0.52 (95% CI: 0.35, 0.77), for 1 log-scale-increment of GPX3 and SELENOP, respectively. A decline in Se biomarkers during pregnancy was associated with a higher risk of GDM and higher HOMA-IR. Low GPX3 activity in late pregnancy was associated with a higher risk of large for gestational-age offspring, partly (∼20%) mediated by fasting glucose concentrations (P = 0.006).

CONCLUSIONS

Low serum Se in pregnancy, particularly GPX3 activity, is independently associated with risk of GDM and large for gestational age. Offering Se status assessment in pregnancy identifies females at high risk for GDM who may benefit from Se substitution.

Novel phenoxy-((phenylethynyl) selanyl) propan-2-ol derivatives as potential anticancer agents

Selenocompounds protect against damage to healthy cells and induce the death of tumor cells by apoptosis; for this reason, they are attractive compounds for cancer research. In the present study, two series of novel phenoxy-((phenylethynyl) selanyl) propan-2-ol derivatives were synthesized, and their anti-proliferation activities were evaluated. Of the 23 compounds synthesized, most showed potent anti-proliferative activity against human cancer cell lines. Specifically, compounds 3h, 3g, and 3h-2, which had a 2- or 4-position halogen substituent on 1-((phenylethynyl)selanyl)-3-phenoxypropan-2-ol, exhibited the best anti-proliferative activity against tumor cells. Flow cytometry demonstrated that 3h, 3g, and 3h-2 induced G2/M phase arrest and apoptosis in A549 cells. Cellular studies demonstrated that the induction of apoptosis by 3h correlated with changes in the expression of cell cycle-related proteins and apoptosis-related proteins. Xenograft tumor experiments in nude mice revealed that compound 3h has antitumor effects in vivo and no evident toxic effects in nude mice. In addition, compound 3h alleviated cisplatin-induced liver and kidney damage. These findings uncover the applicability of compound 3h as a novel lead compound for cancer treatment.

A modified selective optical sensor for selenium determination based on incorporating xylenol orange in a poly(vinyl chloride) membrane

A novel optical sensor has been developed to measure selenium ions. The sensor membrane was created by mixing xylenol orange (XO) and sodium tetraphenylborate (NaTPB) with a plasticized poly(vinyl chloride) membrane that contained o-nitrophenyl octyl ether (o-NPOE) as a plasticizer. XO was previously established for use in a colorimeter to measure selenium in water and other media. At pH 6.6, the color of the detecting membrane changed from orange to pink when in contact with Se4+ ions. Various variables affecting the uptake efficiency were evaluated and optimized. Under optimum conditions (i.e., 30% PVC, 60% o-NPOE, and 5.0% of both XO and NaTPB for 5.0 min as the response time), the proposed sensor displayed a linear range 10-175 ng mL-1 with the detection and quantification limits of 3.0 and 10 ng mL-1, respectively. Also, the precision (RSD%) was better than 2.2% for six replicate determinations of 100 ng mL-1 Se4+ in various membranes. For the detection of Se4+, the selectivity of the sensor membrane was investigated for a number of possible interfering inorganic cations, but no appreciable interference was found. With the use of a 0.3 M HCl solution, the sensor was successfully restored, and the response that may have been reversible and reproducible exhibited an RSD% of less than 2.0%. The sensor has been successfully used to analyze Se4+ ions in environmental and biological materials.

Selenium in Infants and Preschool Children Nutrition: A Literature Review

Selenium (Se), an essential trace element, is fundamental to human health, playing an important role in the formation of thyroid hormones, DNA synthesis, the immune response, and fertility. There is a lack of comprehensive epidemiological research, particularly the serum Se concetration in healthy infants and preschool children compared to the estimated dietary Se intake. However, Se deficiencies and exceeding the UL have been observed in infants and preschool children. Despite the observed irregularities in Se intake, there is a lack of nutritional recommendations for infants and preschool children. Therefore, the main objective of this literature review was to summarize what is known to date about Se levels and the risk of deficiency related to regular consumption in infants and preschool children.

Oxidative Stress and Male Infertility: The Protective Role of Antioxidants

Oxidative stress is a significant factor in male infertility, compromising sperm function and overall reproductive health. As male infertility garners increasing attention, effective therapeutic interventions become paramount. This review investigates the therapeutic role of antioxidants in addressing male infertility. A detailed examination was conducted on antioxidants such as vitamin C, E, B12, D, coenzyme Q10, zinc, folic acid, selenium, l-carnitine, l-arginine, inositols, and alpha-lipoic acid. This analysis examines the methodologies, outcomes, and constraints of current clinical studies. Antioxidants show notable potential in counteracting the negative effects of oxidative stress on sperm. Based on the evidence, these antioxidants, individually or synergistically, can enhance sperm health and reproductive outcomes. However, certain limitations in the studies call for careful interpretation. Antioxidants are integral in tackling male infertility attributed to oxidative stress. The current findings underscore their therapeutic value, yet there's a pressing need for deeper, comprehensive research. Future studies should focus on refining dosage guidelines, identifying potential side effects, and discerning the most efficacious antioxidant combinations for male infertility solutions.

Are epigenetic mechanisms and nutrition effective in male and female infertility?

This review discusses epigenetic mechanisms and the relationship of infertility in men and women in relation to parameters pertaining to nutrition. The prevalence of infertility worldwide is 8-12 %, and one out of every eight couples receives medical treatment. Epigenetic mechanisms, aging, environmental factors, dietary energy and nutrients and non-nutrient compounds; more or less energy intake, and methionine come into play in the occurrence of infertility. It also interacts with vitamins B12, D and B6, biotin, choline, selenium, zinc, folic acid, resveratrol, quercetin and similar factors. To understand the molecular mechanisms regulating the expression of genes that affect infertility, the environment, the role of genotype, age, health, nutrition and changes in the individual's epigenotype must first be considered. This will pave the way for the identification of the unknown causes of infertility. Insufficient or excessive intake of energy and certain macro and micronutrients may contribute to the occurrence of infertility as well. In addition, it is reported that 5-10 % of body weight loss, moderate physical activity and nutritional interventions for improvement in insulin sensitivity contribute to the development of fertility. Processes that pertain to epigenetics carry alterations which are inherited yet not encoded via the DNA sequence. Nutrition is believed to have an impact over the epigenetic mechanisms which are effective in the pathogenesis of several diseases like infertility. Epigenetic mechanisms of individuals with infertility are different from healthy individuals. Infertility is associated with epigenetic mechanisms, nutrients, bioactive components and numerous other factors.

The Crucial Role of Diet Therapy and Selenium on the Evolution of Clinical and Paraclinical Parameters in Patients with Metabolic Syndrome

Oxidative stress (OS) is associated with metabolic syndrome (MS) and represents a complex disease association that has become a major challenge in the field of public health. The aim of this study was to investigate the effectiveness of introducing selenium in the management of OS, while considering a balanced diet based on a healthy lifestyle and dietary therapy. A total of 206 individuals participated voluntarily in the study, divided into three groups: the control group with 35 individuals (17.0%) designated as control lot (LC), the group undergoing diet therapy with 119 individuals (57.8%) designated as diet therapy lot (LD), and the group undergoing diet therapy supplemented with selenium consisting of 52 individuals (25.2%) designated as diet therapy with selenium lot (LD + Se). The study assessed various clinical parameters (such as body mass index (BMI), body weight status, fat mass, visceral fat, and sarcopenic index), paraclinical parameters (including HOMA index, cholesterol, triglycerides, C-reactive protein, and glycosylated haemoglobin (HGS)), as well as OS parameters (measured using the FORD test, FORT test, and MIXED test). The LD + Se group demonstrated the most favourable results in terms of BMI reduction, decreased fat and visceral mass, reduced levels of C-reactive protein, and improved glycosylated haemoglobin levels. By implementing a balanced diet therapy and supplementing the diet with selenium, it was possible to achieve a reduction in adipose tissue and glycosylated haemoglobin levels, ultimately contributing to the reduction of OS in the body.

Genetic variants associated with spontaneous preterm birth in women from India: a prospective cohort study

Background

Despite having the highest number of preterm births globally, no genomic study on preterm birth was previously published from India or other South-Asian countries.

Methods

We conducted a genome-wide association (GWA) study of spontaneous preterm birth (sPTB) on 6211 women from India. We used a novel resampling procedure to identify the associated single nucleotide polymorphisms (SNPs) followed by haplotype association analysis and imputation.

Findings

We found that 512 maternal SNPs were associated with sPTB (p < 2.51e-3), of which minor allele at 19 SNPs (after Bonferroni correction) had increased genotype relative risk. Haplotypes containing six of the 19 SNPs (rs13011430, rs8179838, rs2327290, rs4798499, rs7629800, and rs13180906) were associated with sPTB (p < 9.9e-4; Bonferroni adjusted p-value <0.05). After imputation in regions around the 19 SNPs, 15 imputed SNPs were found to be associated with sPTB (Bonferroni adjusted p-value <0.05). One of these imputed SNPs, rs35760881, and three other SNPs (rs17307697, rs4308815, and rs10983507) were also reported to be associated with sPTB in women belonging to European ancestry. Moreover, we found that GG genotype at rs1152954, one of the associated SNPs, enhanced risk of sPTB and reduced telomere length.

Interpretation

This is the first study from South Asia on the genome-wide identification of maternal SNPs associated with sPTB. These SNPs are known to alter the expression of genes associated with major pathways in sPTB viz. inflammation, apoptosis, cervical ripening, telomere maintenance, selenocysteine biosynthesis, myometrial contraction, and innate immunity. From a public health perspective, the trans-ethnic association of four SNPs identified in our study may help to stratify women with risk of sPTB in most populations.

Funding

Department of Biotechnology (India), Grand Challenges India - All Children Thriving Program and Biotechnology Industry Research Assistance Council (BIRAC).

Selenium and Selenoproteins in Health

Selenium is a trace mineral that is essential for health. After being obtained from food and taken up by the liver, selenium performs various physiological functions in the body in the form of selenoproteins, which are best known for their redox activity and anti-inflammatory properties. Selenium stimulates the activation of immune cells and is important for the activation of the immune system. Selenium is also essential for the maintenance of brain function. Selenium supplements can regulate lipid metabolism, cell apoptosis, and autophagy, and have displayed significant alleviating effects in most cardiovascular diseases. However, the effect of increased selenium intake on the risk of cancer remains unclear. Elevated serum selenium levels are associated with an increased risk of type 2 diabetes, and this relationship is complex and nonlinear. Selenium supplementation seems beneficial to some extent; however, existing studies have not fully explained the influence of selenium on various diseases. Further, more intervention trials are needed to verify the beneficial or harmful effects of selenium supplementation in various diseases.

Serum Essential Trace Element Status in Women and the Risk of Endometrial Diseases: a Case-Control Study : Serum Essential Trace Element Status in Women and the Risk of Endometrial Diseases: a Case-Control Study

Endometrial diseases, including uterine fibroids, polyps, intrauterine adhesion, endometritis, etc., are the major causes of infertility among women. However, the association between essential trace element status in women and the risk of endometrial disease is limited and unclear. This study aimed to investigate this association using a case-control study design; a total of 302 women patients with endometrial diseases and 302 healthy women were included. Compared to women in the control group, serum selenium (Se) (p = 0.024) and zinc (Zn) (p = 0.017) levels were significantly lower, while copper (Cu) (p = 0.004) and molybdenum (Mo) (p = 0.005) levels were significantly higher among women with endometrial diseases. In addition, compared to women in the first quartile of the copper/zinc (Cu/Zn) ratio value group, the adjusted ORs (95% CIs) of endometrial diseases were 1.50 (1.05, 2.14), 1.68 (1.18, 2.39), and 1.47 (1.02, 2.10), respectively, in the second, third, and fourth quartile of the Cu/Zn ratio value group (p trend = 0.047). In addition, the results from restricted cubic splines showed that the dose-response relationships of serum levels of these essential elements with the risk of endometrial diseases were nonlinear for Se, Cu, and Zn and relatively linear for Mo and Cu/Zn ratio. The present study showed serum levels of Zn and Se among women with endometrial diseases were significantly lower compared to that among healthy women, while serum levels of Cu and Mo were significantly higher, in addition, the serum Cu/Zn ratio value was also significantly and positively associated with the risk of endometrial diseases.

Attenuating effects of selenium and zinc against hexavalent chromium-induced oxidative stress, hormonal instability, and placenta damage in preimplanted rats

As a toxic metal, hexavalent chromium (CrVI) has effects on both the reproductive and endocrine systems. This study aimed to evaluate the protective effects of selenium (Se) and zinc (Zn) against the toxicity of chromium on the placenta in pregnant Wistar albino rats. Thirty pregnant Wistar rats were divided into control and four treated groups, receiving subcutaneously (s.c) on the 3rd day of pregnancy, K₂Cr₂O₇ (10 mg/kg body weight (bw)) alone, or in association with Se (0.3 mg/kg bw), ZnCl₂ (20 mg/kg bw), or both of them simultaneously. Plasma steroid hormones, placenta histoarchitecture, oxidative stress profile, and developmental parameters were investigated. These results showed that K₂Cr₂O₇ exposure induced a significant increase in the levels of both plasma estradiol (E₂) and placenta malondialdehyde (MDA), the number of fetal resorptions, and percent of post-implantation loss. On the other hand, K₂Cr₂O₇ significantly reduced developmental parameters, maternal body and placenta weight, and plasma progesterone (P) and chorionic gonadotropin hormone (β HCG) levels. However, K₂Cr₂O₇ significantly decreased the placenta activities of superoxide dismutase (SOD), glutathione peroxidase (GPx), reduced glutathione (GSH), and nonprotein sulfhydryl (NPSH). These changes have been reinforced by histopathological evaluation of the placenta. Se and/or ZnCl₂ supplementation provoked a significant improvement in most indices. These results suggest that the co-treatment with Se or ZnCl₂ strongly opposes the placenta cytotoxicity induced by K₂Cr₂O₇ through its antioxidant action.

Selenium and Zinc Intakes of Staple Grains and Their Correlation with Urine Selenium and Zinc in the Tibetan Rural Residents along the Yarlung Zangbo River

Grains account for a large proportion of the diet of rural residents in Tibet. The lack of selenium (Se) and zinc (Zn) threatens the population's nutrition and health. However, the intakes of selenium and zinc in grains remains unclear. To clarify the nutritional status of selenium and zinc consumed from staple grains of residents along the Yarlung Zangbo River in Tibet, 341 grain samples and 242 urine samples were collected, and 244 food frequency questionnaires were completed along the Yarlung Zangbo River in 2020-2021. The results showed that the selenium concentrations of 88.5% of self-produced tsampa and 80.8% of self-produced flour were lower than the grain selenium threshold (<25 μg·kg^-1). The intake of selenium and zinc from staple grains (tsampa, flour, and rice) contributed 15.0% and 43.5% to the recommended nutrient intake (RNI) on average, respectively. A geographical detector model analyzed factors affecting urinary selenium and zinc levels. Selenium and zinc intakes in rice and flour, and dietary diversity score (DDS) were the main factors affecting urinary selenium and zinc (p < 0.01). Their interaction effects on urinary selenium and zinc were greater than those of a single factor. The staple grains of rural residents along the Yarlung Zangbo River were in a state of selenium deficiency. The zinc content of the staple grain purchased was lower than that of the main grain produced by rural residents. Changing the grain consumption pattern and adjusting the proportion of exogenous grains can improve selenium and zinc nutrition in residents.

Selenium as a Factor Moderating Depression and Obesity in Middle-Aged Women

The aim of this study was to evaluate the effect of serum selenium on PPAR-γ and the selected proinflammatory cytokines (IL-1β, IL-6, TNF-α) in relation to depressive symptoms and obesity in middle-aged women. The research procedure was as follows: a survey was performed using the authors’ questionnaire and the BDI, anthropometric measurements, and the analysis of blood for the levels of selenium, cytokines, and genetic analysis of the PPAR-γ polymorphism (n = 443). It was found that the BMI increased along with the concentration of IL-6. No moderating effect of selenium was observed, although the cut-off values for “p” were established for IL-β*Se (p = 0.068) and IL-6*Se (p = 0.068), so there was a potential association with these two markers. At high selenium levels, the effect of higher IL-β levels on a decrease in BMI was stronger, as was the effect of an increase in IL-6 levels on an increase in BMI. No effect of selenium on PPAR-γ was found in relation to depressive symptoms and obesity. Higher selenium levels may have a beneficial effect on BMI even at high IL-β concentrations, however, at high IL-6 concentrations, this effect was not observed. Selenium levels had no impact on depressive symptoms.

Selenium Status and Oxidative Stress in SARS-CoV-2 Patients

Background and Objectives: Insufficient intake of essential micronutrient selenium (Se) increases the susceptibility to diseases associated with oxidative stress. The study aim was to assess Se status and oxidative stress in COVID-19 patients depending on severity of the disease. Materials and Methods: Blood plasma of 80 post-COVID-19 disease patients and 40 acutely ill patients were investigated. Concentration of Se was detected by a fluorometric method with di-amino-naphthalene using acidic hydrolysis. Selenoprotein P (Sepp1), malondialdehyde (MDA), and 4-hydroxynonenal (4-HNE) and their metabolite adducts were evaluated by spectrophotometric methods using commercial assay kits. Results: Obtained results demonstrated that Se and Sepp1 concentration in acute patients were significantly (p < 0.05 for Se and p < 0.001 for Sepp1) decreased compared with post-COVID-19 disease patients. However, in post-COVID-19 disease patients, Se values were close to the low limit of the norm for the European population. 4-HNE adducts concentration as a marker of lipid peroxidation was significantly increased in the acute patients group compared to the recovery group (p < 0.001). Conclusions: COVID-19 pathology is characterized by the induction of oxidative stress and suppression of antioxidant defenses during the acute phase. Lower levels of Se and Sepp1 and higher levels of reactive oxygen species reflect this imbalance, highlighting the role of oxidative stress in the disease’s pathogenesis.

Alterations in Antioxidant Micronutrient Concentrations in Placental Tissue, Maternal Blood and Urine and the Fetal Circulation in Pre-eclampsia

Trace elements such as selenium and zinc are vital components of many enzymes, including endogenous antioxidants, and can interact with each other. Women with pre-eclampsia, the hypertensive disease of pregnancy, have been reported as having changes in some individual antioxidant trace elements during pregnancy, which are related to maternal and fetal mortality and morbidity. We hypothesised that examination of the three compartments of (a) maternal plasma and urine, (b) placental tissue and (c) fetal plasma in normotensive and hypertensive pregnant women would allow identification of biologically significant changes and interactions in selenium, zinc, manganese and copper. Furthermore, these would be related to changes in the angiogenic markers, placental growth factor (PlGF) and Soluble Fms-Like Tyrosine Kinase-1 (sFlt-1) concentrations. Venous plasma and urine were collected from healthy non-pregnant women (n = 30), normotensive pregnant controls (n = 60) and women with pre-eclampsia (n = 50) in the third trimester. Where possible, matched placental tissue samples and umbilical venous (fetal) plasma were also collected. Antioxidant micronutrient concentrations were measured by inductively coupled plasma mass-spectrometry. Urinary levels were normalised to creatinine concentration. Plasma active PlGF and sFlt-1 concentrations were measured by ELISA. Maternal plasma selenium, zinc and manganese were all lower in women with pre-eclampsia (p < 0.05), as were fetal plasma selenium and manganese (p < 0.05 for all); maternal urinary concentrations were lower for selenium and zinc (p < 0.05). Conversely, maternal and fetal plasma and urinary copper concentrations were higher in women with pre-eclampsia (p < 0.05). Differences in placental concentrations varied, with lower overall levels of selenium and zinc (p < 0.05) in women with pre-eclampsia. Maternal and fetal PlGF were lower and sFlt-1 higher in women with pre-eclampsia; maternal plasma zinc was positively correlated with maternal plasma sFlt-1 (p < 0.05). Because of perceptions that early- and late-onset pre-eclampsia have differing aetiologies, we subdivided maternal and fetal data accordingly. No major differences were observed, but fetal sample sizes were small following early-onset. Disruption in these antioxidant micronutrients may be responsible for some of the manifestations of pre-eclampsia, including contributing to an antiangiogenic state. The potential benefits of mineral supplementation, in women with deficient intakes, during pregnancy to reduce pre-eclampsia remain an important area for experimental and clinical research.

Recent Trends in Hydroxyapatite Supplementation for Osteoregenerative Purposes

Bone regeneration has gained attention in the biomedical field, which has led to the development of materials and synthesis methods meant to improve osseointegration and cellular bone activity. The properties of hydroxyapatite, a type of calcium phosphate, have been researched to determine its advantages for bone tissue engineering, particularly its biocompatibility and ability to interact with bone cells. Recently, the advantages of utilizing nanomolecules of hydroxyapatite, combined with various substances, in order to enhance and combine their characteristics, have been reported in the literature. This review will outline the cellular and molecular roles of hydroxypatite, its interactions with bone cells, and its nano-combinations with various ions and natural products and their effects on bone growth, development, and bone repair.

Sperm mitochondrial DNA copy number mediates the association between seminal plasma selenium concentrations and semen quality among healthy men

Selenium (Se) is essential for successful male reproduction. However, the association of Se status with human semen quality remains controversial and the underlying mechanisms are poorly understood. We measured seminal plasma Se concentrations, sperm mitochondrial DNA copy number (mtDNAcn), and sperm quality parameters among healthy Chinese men screened as potential sperm donors. Linear mixed-effects models were used to investigate the associations of within-subject pooled seminal plasma Se concentrations (n = 1159) with repeated sperm quality parameters (n = 5617); mediation analyses were applied to evaluate the mediating role of sperm mtDNAcn (n = 989). Seminal plasma Se concentrations were positively associated with sperm concentration and total count (both P for trend < 0.001). In adjusted models, men in the top vs. bottom quartiles of seminal plasma Se concentrations had 70.1 % (95 % CI: 53.3 %, 88.9 %) and 59.1 % (95 % CI: 40.5 %, 80.2 %) higher sperm concentration and total count, respectively. Meanwhile, we observed inverse associations between seminal plasma Se concentrations and sperm mtDNAcn, and between sperm mtDNAcn and sperm motility, concentration, and total count (all P for trend < 0.05). Mediation analyses suggested that sperm mtDNAcn mediated 19.7 % (95 % CI: 15.9 %, 25.3 %) and 23.1 % (95 % CI: 17.4 %, 33.4 %) of the associations between seminal plasma Se concentrations and sperm concentration and total count, respectively. Our findings suggest that Se is essential for male spermatogenesis, potentially by affecting sperm mtDNAcn.

The Effect of Selenium Supplementation on Clinical Outcomes, Metabolic Profiles, and Pulsatility Index of the Uterine Artery in High-Risk Mothers in Terms of Preeclampsia Screening with Quadruple Test: a Randomized, Double-Blind, Placebo-Controlled Clinical Trial : Selenium and preeclampsia

Data on the effects of selenium (Se) supplementation on clinical outcomes, metabolic profiles, and pulsatility index (PI) in high-risk mothers in terms of preeclampsia (PE) screening with quadruple tests are scarce. This study evaluated the effects of Se supplementation on clinical outcomes, metabolic profiles, and uterine artery PI on Doppler ultrasound in high-risk mothers in terms of PE screening with quad marker. The current randomized, double-blind, placebo-controlled trial was conducted among 60 high-risk pregnant women screening for PE with quad tests. Participants were randomly allocated into two groups (30 participants each group), received either 200 µg/day Se supplements (as Se amino acid chelate) or placebo from 16 to 18 weeks of pregnancy for 12 weeks. Clinical outcomes, metabolic profiles, and uterine artery PI were assessed at baseline and at the end of trial. Se supplementation resulted in a significant elevation in serum Se levels (β 22.25 µg/dl; 95% CI, 18.3, 26.1; P < 0.001) compared with the placebo. Also, Se supplementation resulted in a significant elevation in total antioxidant capacity (β 82.88 mmol/L; 95% CI, 3.03, 162.73; P = 0.04), and total glutathione (β 71.35 µmol/L; 95% CI, 5.76, 136.94; P = 0.03), and a significant reduction in high-sensitivity C-reactive protein levels (β - 1.52; 95% CI, - 2.91, - 0.14; P = 0.03) compared with the placebo. Additionally, Se supplementation significantly decreased PI of the uterine artery in Doppler ultrasound (β - 0.09; 95% CI, - 0.14, - 0.04; P = 0.04), and a significant improvement in depression (β - 5.63; 95% CI, - 6.97, - 4.28; P < 0.001), anxiety (β - 1.99; 95% CI, - 2.56, - 1.42; P < 0.001), and sleep quality (β - 1.97; 95% CI, - 2.47, - 1.46; P < 0.001). Se supplementation for 12 weeks in high-risk pregnant women in terms of PE screening with quad marker had beneficial effects on serum Se level, some metabolic profiles, uterine artery PI, and mental health. IRCT Registration: htpp:// www.irct.ir ; identifier IRCT20200608047701N1.

Biological Activity of Selenium and Its Impact on Human Health

Selenium (Se) is a naturally occurring metalloid element essential to human and animal health in trace amounts but it is harmful in excess. Se plays a substantial role in the functioning of the human organism. It is incorporated into selenoproteins, thus supporting antioxidant defense systems. Selenoproteins participate in the metabolism of thyroid hormones, control reproductive functions and exert neuroprotective effects. Among the elements, Se has one of the narrowest ranges between dietary deficiency and toxic levels. Its level of toxicity may depend on chemical form, as inorganic and organic species have distinct biological properties. Over the last decades, optimization of population Se intake for the prevention of diseases related to Se deficiency or excess has been recognized as a pressing issue in modern healthcare worldwide. Low selenium status has been associated with an increased risk of mortality, poor immune function, cognitive decline, and thyroid dysfunction. On the other hand, Se concentrations slightly above its nutritional levels have been shown to have adverse effects on a broad spectrum of neurological functions and to increase the risk of type-2 diabetes. Comprehension of the selenium biochemical pathways under normal physiological conditions is therefore an important issue to elucidate its effect on human diseases. This review gives an overview of the role of Se in human health highlighting the effects of its deficiency and excess in the body. The biological activity of Se, mainly performed through selenoproteins, and its epigenetic effect is discussed. Moreover, a brief overview of selenium phytoremediation and rhizofiltration approaches is reported.

Selenium status in term neonates, according to birth weight and gestational age, in relation to maternal hypertensive pathology

Background

Pregnancy represents a state of increased oxidative stress and antioxidants, in which selenium (Se) plays a pivotal role, contribute to maintain the oxidative balance. If antioxidant defenses are depleted, placental function is disrupted, resulting in pregnancy complications, including pregnancy-induced hypertension (PIH). Little is known about fetal selenium status in concomitant relation to maternal PIH, gestational age (GA) and birthweight (BW).

Methods

We examined over a 3-year period the serum (SeS) and urine selenium (SeU) status in term neonates from normotensive (nonPIH) and hypertensive (PIH) mothers as clinical markers of oxidative stress. In this retrospective observational study, 72 neonates with maternal PIH were matched for GA and BW to 72 neonates of normotensive mothers. Four groups were obtained, based on maternal PIH and BW relative to GA (appropriate-for-gestational-age-AGA, small-for-gestational-age-SGA): nonPIH-AGA (control group), nonPIH-SGA, PIH-AGA, and PIH-SGA.

Results

The results showed significant differences (p < 0.001) in selenium levels among the study groups: SeS - 44.85 ± 7.56 μg/L in nonPIH-AGA, 39.62 ± 11.42 μg/L in nonPIH-SGA, 40.01 ± 10.07 μg/L in PIH-AGA, and 25.39 ± 8.99 μg/L in PIH-SGA; SeU - 27.98 ± 7.99 μg/L in nonPIH-AGA, 22.85 ± 9.48 μg/L in nonPIH-SGA, 23.44 ± 6.73 μg/L in PIH-AGA, and 13.05 ± 5.86 μg/L in PIH-SGA. Selenium depletion was more common in neonates born from hypertensive mothers and those born small for gestational age. Though moderate in intensity, selenium levels were positively correlated with BW (0.319 for SeS, 0.397 for SeU) and negatively correlated with maternal systolic blood pressure (-0.313 for SeS, -0.324 for SeU). The main independent effects on SeS and SeU of each maternal blood pressure and birth weight turned out statistically significant. In interaction, a more pronounced effect was reached in PIH-SGA neonates.

Conclusion

Selenium status seemed to reflect the negative impact that PIH exerts in neonates during intrauterine development. Clinical markers of selenium status could thus be of great value for tracking responses of individuals to selenium supplementation as part of health improvement and harm mitigation approaches.

Transcriptome sequencing reveals the effect of selenium nanoparticles on primary hepatocytes of rainbow trout

Heat stress is one of the important threats in rainbow trout culture, and selenium nanoparticles (SeNPs) have an important role in combating heat stress and enhancing immunity. In this study, to enable rainbow trout to survive at higher temperatures, we added 5 µg/mL SeNPs to hepatocytes to study the resistance effect and immune effect of SeNPs against heat stress, thus enabling rainbow trout to adapt to summer temperatures (Average 26 °C) in Lanzhou, Gansu Province, China. Therefore, we investigated the transcriptome expression profile of hepatocytes spiked with SeNPs when exposed to heat stress. A total of 234 differentially expressed genes (DEGs) were firmly established in SeNPs-added group when exposed to heat stress compared to non-SeNPs-added group. Of these DEGs, 156 were up-regulated and 78 were down-regulated. These DEGs were grouped into different Gene Ontology (GO) functional terms and enriched in 75 significantly different Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, of which approximately-one-third (19) were associated with immunity. STRING was used to identify 39 key immune DEGs belonging to 5 immune pathways (C-type lectin receptor signaling pathway, FoxO signaling pathway, Toll-like receptor signaling pathway, RIG-I-like receptor signaling pathway, and Rachidonic acid metabolism). These pathways interact extensively and formed a complex network to regulate heat stress. These results provided an important basis for future elucidation of the role of SeNPs in heat stress resistance and immune enhancement in rainbow trout.