Geochemical characteristics, source analysis, influencing factors, and reserves of soil Selenium in Wuming, Guangxi, China.

Although selenium (Se) reserves are crucial for the development and exploitation of Se-rich resources in karst soil areas, research on these reserves is still limited. A comprehensive study was conducted in a typical karst region known for its Se richness. A total of 12,547 surface soil samples, 134 deep soil samples, and 60 soil profiles from various locations were systematically collected. The findings showed that the Se content in the surface soil ranged from 0.073 to 9.04 mg/kg, with a baseline level of 0.84 mg/kg. This underscores the high background level and moderate variability in the region. Surface soil Se exhibited a notable positive correlation with deep soil Se, and an inverse correlation with pH (p < 0.01). One-way analysis of variance indicated that land formations and soil structure were the primary determinants affecting the concentration of Se in the topsoil (p = 0.000), with parent rock type and land-use type following closely (p = 0.003). In addition, the study included an investigation of soil Se variations with depth using 60 soil profiles. Through this analysis, it was revealed that Se content exhibited an exponential change with depth. Multiple integrations were employed to derive formulas for calculating Se reserves in the 0-200 cm depth range. Following these calculations, the estimations of Se stockpile across diverse types of source materials, varieties of soils, and land management methods were determined, highlighting the findings using a passive construction. This paper lays the groundwork for advancing the extraction and application of Se.

Constructing surface protective film of V-Se-O to promote zinc ion storage by surface oxygen implantation strategy.

Interfacial chemical modification is an effective strategy to adjust the strong Coulombic ion-lattice interactions with high valence cations experienced by electrode materials, facilitating the reaction kinetic. In this paper, a simple and fast surface oxygen implantation strategy was designed to adjust the electronic structure of stainless steel (SS) supported vanadium diselenide (VSe2) nanosheets and form a surface protective film, which effectively accelerates the reaction kinetics of Zn2+ and extends the cycle life of the battery. It is demonstrated that the conductivity, pseudocapacitance and specific capacity can be tuned by selectively introducing oxygen species to the surface, which provides an important reference for the design of electrodes with controlled surface chemistry. Density functional theory (DFT) calculations also confirm that the electronic structure can be adjusted by surface oxygen injection strategy, which not only improves the conductivity, but also adjusts the adsorption energy, thus providing favorable conditions for zinc ion storage. Benefiting from the selenium vacancies and pores generated by the removal of part of selenium, and the oxide film formed on the surfaces, the VSe2-xOx-SS-30 electrode showed higher specific capacity (188.4 mAh/g at 0.5 A g-1 after 50 cycles), better rate performance (107.1 mAh/g at 4 A g-1) and more satisfactory cycling stability (83.1 mAh/g at 5 A g-1 after 1800 cycles) than VSe2-SS electrode. Importantly, the flexible quasi-solid-state VSe2-xOx-SS-30//Zn battery also exhibits high specific capacity and excellent environmental adaptability. Furthermore, the zinc (de)intercalation and transformation reactions mechanism was revealed by some ex-situ/in-situ techniques.

Acute 2-phenyl-3-(phenylselanyl)benzofuran treatment reverses the neurobehavioral alterations induced by sleep deprivation in mice.

Sleep is a fundamental state for maintaining the organism homeostasis. Disruptions in sleep patterns predispose to the appearance of memory impairments and mental disorders, including depression. Recent pre-clinical studies have highlighted the antidepressant-like properties of the synthetic compound 2-phenyl-3-(phenylselanyl)benzofuran (SeBZF1). To further investigate the neuromodulatory effects of SeBZF1, this study aimed to assess its therapeutic efficacy in ameliorating neurobehavioral impairments induced by sleep deprivation (SD) in mice. For this purpose, a method known as multiple platforms over water was used to induce rapid eye movement (REM) SD. Two hours after acute SD (24 h), male Swiss mice received a single treatment of SeBZF1 (5 mg/kg, intragastric route) or fluoxetine (a positive control, 20 mg/kg, intraperitoneal route). Subsequently, behavioral tests were conducted to assess spontaneous motor function (open-field test), depressive-like behavior (tail suspension test), and memory deficits (Y-maze test). Brain structures were utilized to evaluate oxidative stress markers, monoamine oxidase (MAO) and acetylcholinesterase (AChE) activities. Our findings revealed that SD animals displayed depressive-like behavior and memory impairments, which were reverted by SeBZF1 and fluoxetine treatments. SeBZF1 also reverted the increase in lipoperoxidation levels and glutathione peroxidase activity in the pre-frontal cortex in mice exposed to SD. Besides, the increase in hippocampal AChE activity induced by SD was overturned by SeBZF1. Lastly, cortical MAO-B activity was reestablished by SeBZF1 in mice that underwent SD. Based on the main findings of this study, it can be inferred that the compound SeBZF1 reverses the neurobehavioral alterations induced by sleep deprivation in male Swiss mice.

The correlation between selenium intake and lung function in asthmatic people: a cross-sectional study.

Objective: This study aimed to examine the correlation between selenium intake and lung function in asthmatic people. Methods: A total of 4,541 individuals in the US National Health and Nutrition Examination Survey (NHANES) were included in this study. Multivariate linear regression, variance inflation factor, restricted cubic splines and quantile regression were used to analyze the relationship between Se intake and lung function. We divided selenium intake into four levels based on quartiles: Q1: Se ≤ 76.75 mcg/d; Q2: 76.75-105.1 mcg/d; Q3: 105.1-137.65 mcg/d; and Q4: Se ≥137.65 mcg/d. Results: Asthma was negatively associated with the Ratio of Forced Expiratory Volume 1st Second to Forced Vital Capacity (FEV1/FVC) (ß = -0.04, 95% CI: -0.06 to -0.02) and FEV1 (ß = -215, 95% CI: -340 to -90). Se intake was positively associated with Forced Expiratory Volume 1st Second (FEV1) (ß =3.30 95% CI: 2.60 to 4.00) and Forced Vital Capacity (FVC) (ß =4.30, 95% CI: 3.50 to 5.10). In asthmatic individuals, the positive effects of Se intake on FVC were enhanced with increasing Se intake, while the positive effects of Se intake on FEV1 varied less dramatically. High Se intake (Q4 level, above 137.65 mcg/d) improved FVC (ß = 353, 95% CI: 80 to 626) and FEV1 (ß = 543, 95% CI: 118 to 969) in asthmatic patients compared to low Se intake (Q1 level, below 76.75 mcg/d). At the Q2 level (76.75-105.1 mcg/d) and Q4 level (Se ≥137.65 mcg/d) of Se intake, the correlation between FEV1 and asthma disappeared. Conclusion: Our research has revealed a positive correlation between selenium intake and lung function in asthma patients and the strength of this positive correlation is related to the amount of selenium intake. We recommend that asthma patients consume 137.65 mcg to 200 mcg of selenium daily to improve pulmonary function while avoiding the adverse effects of selenium on the human body.

Combined transcriptome and metabolome analyses reveal the effects of selenium on the growth and quality of Lilium lancifolium.

Lilium lancifolium Thunb (L. lancifolium) is an important medicinal and edible plant with outstanding functionality for selenium (Se) biofortification. However, the molecular response of L. lancifolium to exogenous Se has not been fully elucidated. In this study, the effects of different levels of Se on L. lancifolium growth and quality were explored by transcriptome, metabolome and biochemical analyses. The results showed that the total Se and organic Se content in L. lancifolium bulbs increased with increasing Se dosage (0-8.0 mmol/L). Moreover, Se stimulated the growth of L. lancifolium at low level (2.0 mmol/L) but showed an inhibitory effect at high levels (≥4.0 mmol/L). Metabolomic and biochemical analyses revealed that the bulb weight and the content of amino acid, soluble sugar, and soluble protein were significantly increased in the 2.0 mmol/L Se treatment compared with those in the control (0 mmol/L Se). Transcriptome and metabolome analyses revealed that the significant upregulation of the GPD1, GPAT and ADPRM genes promoted glycerophospholipid accumulation. Additionally, the significantly upregulated glyA and downregulated asnB, nadB, thrA and SAT genes coordinate to the regulation of amino acid biosynthesis. The significantly upregulated SUS, bgl B, BAM, and SGA1 genes were involved in soluble sugar accumulation under Se treatment. In summary, this study identified the optimal Se concentration (2.0 mmol/L), which significantly improved the growth and nutritional quality of L. lancifolium and contributed to understanding the combined effects of Se treatment on the expression of genes and the accumulation of metabolites in L. lancifolium bulbs.

Toenail and blood selenium mediated regulation of thyroid dysfunction through immune cells: a mediation Mendelian randomization analysis.

Purpose: Specific nutrients found in food, such as minerals, antioxidants, and macronutrients, have a significant impact on immune function and human health. However, there is currently limited research exploring the relationship between specific nutrients, immune system function, and thyroid dysfunction commonly observed in autoimmune thyroid diseases, which manifest predominantly as hyperthyroidism or hypothyroidism. Therefore, the objective of this study was to investigate the connections between dietary traits and thyroid dysfunction, as well as the potential mediating role of immune cells, using Mendelian randomization (MR) analysis. Methods: The two-step MR analysis used single-nucleotide polymorphisms as instruments, with a threshold of p < 5e-08 for nutrients and thyroid dysfunction, and p < 5e-06 for immune cells. Data from different GWAS databases and UK Biobank were combined to analyze 8 antioxidants and 7 minerals, while the data for 4 macronutrients came from a cohort of 235,000 individuals of European. The outcome data (hypothyroidism, N = 3340; hyperthyroidism, N = 1840; free thyroxin [FT4], N = 49,269; thyroid-stimulating hormone [TSH], N = 54,288) were source from the ThyroidOmics consortium. Immune trait data, including 731 immune phenotypes, were collected from the GWAS catalog. Results: The results revealed that nutrient changes, such as lycopene, toenail and blood selenium, and α-tocopherol, impacted the immune system. Immune cells also affected thyroid function, with cDC cells promoting hypothyroidism and median fluorescence intensity (MFI) phenotypes correlating strongly with FT4 levels. Toenail and blood selenium reduce the relative cell counts (RCC) phenotypes of immune cells (CD62L- plasmacytoid DC %DC and transitional B cells %Lymphocyte), thereby diminishing its promoting effect on hypothyroidis. Furthermore, toenail and blood selenium mainly impacted phenotypes in three types of T cells (CD25 + ⁣ + CD8br, CD3 on CD45RA- CD4+, and CD45RA on Terminally Differentiated CD8br), reinforcing the negative regulation of FT4 levels. Conclusion: The role of immune cells as mediators in the relationship between nutrients and thyroid dysfunction highlights their potential as diagnostic or therapeutic markers. Toenail and blood selenium levels can indirectly impact hypothyroidism by influencing the RCC levels of two types of immune cells, and can indirectly affect FT4 levels by influencing three types of T cells.

Selenium Nanoparticles as Neuroprotective Agents: Insights into Molecular Mechanisms for Parkinson's Disease Treatment.

Oxidative stress and the accumulation of misfolded proteins in the brain are the main causes of Parkinson's disease (PD). Several nanoparticles have been used as therapeutics for PD. Despite their therapeutic potential, these nanoparticles induce multiple stresses upon entry. Selenium (Se), an essential nutrient in the human body, helps in DNA formation, stress control, and cell protection from damage and infections. It can also regulate thyroid hormone metabolism, reduce brain damage, boost immunity, and promote reproductive health. Selenium nanoparticles (Se-NPs), a bioactive substance, have been employed as treatments in several disciplines, particularly as antioxidants. Se-NP, whether functionalized or not, can protect mitochondria by enhancing levels of reactive oxygen species (ROS) scavenging enzymes in the brain. They can also promote dopamine synthesis. By inhibiting the aggregation of tau, α-synuclein, and/or Aß, they can reduce the cellular toxicities. The ability of the blood-brain barrier to absorb Se-NPs which maintain a healthy microenvironment is essential for brain homeostasis. This review focuses on stress-induced neurodegeneration and its critical control using Se-NP. Due to its ability to inhibit cellular stress and the pathophysiologies of PD, Se-NP is a promising neuroprotector with its anti-inflammatory, non-toxic, and antimicrobial properties.

Chondroitin sulfate-functionalized selenium nanoparticle-induced S-phase cell cycle arrest and apoptosis in HeLa Cells.

This study aimed to evaluate the anti-cervical cancer activity of chondroitin sulfate-functionalized selenium nanoparticles (SeCS) and to elucidate their action mechanism. Cytotoxic effect of SeCS on HeLa cells was assessed by MTT assay. Further molecular mechanism of SeCS was analyzed by flow cytometric assay and western blotting. The results showed that treatment with SeCS resulted in a dose- and time-dependent inhibition in the proliferation of HeLa cells. The data obtained from flow cytometry demonstrated that SeCS inhibited HeLa cell growth via the induction of S-phase arrest and cell apoptosis. Further mechanism analysis found that SeCS down-regulated expression levels of cyclin A and CDK2 and up-regulated p21 expression, which contributed to S arrest. Moreover, SeCS increased the level of Bax and decreased the expression of Bcl-2, resulting in the release of cytochrome C from mitochondria and activating caspase-3/8/9 for caspase-dependent apoptosis. Meanwhile, intracellular reactive oxygen species (ROS) levels were elevated after SeCS treatment, suggesting that ROS might be upstream of SeCS-induced S-phase arrest and cell apoptosis. These data show that SeCS has anti-tumor effects and possesses the potential to become a new therapeutic agent or adjuvant therapy for cancer patients. PRACTICAL APPLICATION: In our previous study, we used chondroitin sulfate to stabilize nano-selenium to obtain SeCS to improve the bioactivity and stability of nano-selenium. We found that it possessed an inhibitory effect on HeLa cells. However, the molecular mechanism remains unclear. This study elucidated the mechanism of SeCS damage to HeLa cells. SeCS has the potential to become a new therapeutic agent or adjuvant therapy for cancer patients.

Metalloid transporters in plants: bridging the gap in molecular structure and physiological exaptation.

The rhizosphere contains both essential nutrients and potentially harmful substances for plant growth. Plants, as sessile organisms, must efficiently absorb the necessary nutrients while actively avoiding the uptake of toxic compounds. Metalloids, which are elements that exhibit properties of both metals and nonmetals, can have different effects on plant growth, ranging from being essential and beneficial to being toxic. The toxicity of metalloids in plants arises due to either the dosage of exposure or the specific elemental type. To utilize or detoxify these elements, plants have developed various transporters that regulate their uptake and distribution in plants. Arguably, genomic sequence analysis suggests the presence of such transporter families throughout the plant kingdom, from chlorophytes to higher plants. These transporters form defined families with related transport preferences. The isoforms within these families have evolved with specialized functions regulated by defined selectivity. Hence, understanding transporters' chemistry to atomic detail is important to achieve desired genetic modifications for crop improvement. Here, we outline various adaptations in plant transport systems to deal with metalloids, including their uptake, distribution, detoxification, and homeostasis in plant tissues. Structural parallels are drawn to other nutrient transporter systems to support emerging themes of functional diversity of active sites of transporters, elucidating adaptations of plants to utilize and extrude metalloid concentrations. Considering the observed physiological importance of metalloids, this review intends to highlight the shared and disparate features in metalloid transport systems and their corresponding nutrient transporters.

Fermented goat milk by selenium-enriched Lactobacillus paracasei alleviates depressive psychological disturbance.

Depression is a prevalent psychiatric disease with the characteristic of persistently gloomy mood. The treatment of depression with traditional therapeutic medications suffers from low efficacy and adverse side effects due to the extremely unpredictable courses and uneven responses to treatment. The goal of this paper was to investigate the preparation of selenium-enriched fermented goat milk and the potential mechanism of its intervention on the chronic unpredictable stress-induced depression mice model. The results showed that Se-Lactobacillus paracasei 20241 (Se-20241) significantly alleviated depressive behavior, reversed the upregulation of inflammatory factors, and attenuated glucocorticoid resistance. Meanwhile, the results showed a modulatory function on oxidative stress dysfunction in the liver, hippocampus, and prefrontal cortex. The change in abundance of Ileibacterium, Muribaculaceae, Turicibacter, Dubosiella, and Bifidobacterium was also modified. These results provided the theoretical groundwork for the development of psychoactive probiotic supplements for depressed patients and clarified the probable mechanism of Se-20241 for antidepressant impact on the CUMS model.

De novo assembly and characterization of the transcriptome of Morchella esculenta growth with selenium supplementation.

Although Morchella esculenta (L.) Pers. is an edible and nutritious mushroom with significant selenium (Se)-enriched potential, its biological response to selenium stimuli remains unclear. This study explored the effect of selenium on mushroom growth and the global gene expression profiles of M. esculenta. While 5 µg mL-1selenite treatment slightly promoted mycelia growth and mushroom yield, 10 µg mL-1significantly inhibited growth. Based on comparative transcriptome analysis, samples treated with 5 µg mL-1 and 10 µg mL-1 of Se contained 16,061 (452 upregulated and 15,609 downregulated) and 14,155 differentially expressed genes (DEGs; 800 upregulated and 13,355 downregulated), respectively. Moreover, DEGs were mainly enriched in the cell cycle, meiosis, aminoacyl-tRNA biosynthesis, spliceosome, protein processing in endoplasmic reticulum pathway, and mRNA surveillance pathway in both selenium-treated groups. Among these, MFS substrate transporter and aspartate aminotransferase genes potentially involved in Se metabolism and those linked to redox homeostasis were significantly upregulated, while genes involved in isoflavone biosynthesis and flavonoid metabolism were significantly downregulated. Gene expression levels increased alongside selenite treatment concentration, suggesting that high Se concentrations promoted M. esculenta detoxification. These results can be used to thoroughly explain the potential detoxification and Se enrichment processes in M. esculenta and edible fungi.

Response of selenium pools to drought stress by regulating physio­biochemical attributes and anatomical changes in Gentiana macrophylla.

Selenium (Se), as a vital stress ameliorant, possesses a beneficial effect on mediating detrimental effects of environmental threats. However, the mechanisms of Se in mitigating the deleterious effects of drought are still poorly understood. Gentiana macrophylla Pall. is a well-known Chinese medicinal herb, and its root, as the main medicinal site, has significant therapeutic effects. The purpose of this experiment was to investigate the functions of Se on the seedling growth and physiobiochemical characteristics in G. macrophylla subjected to drought stress. The changes in microstructure and chloroplast ultrastructure of G. macrophylla leaves under drought exposure were characterized by scanning electron microscopy (SEM), scanning electron microscopes and energy dispersive X-Ray spectroscope (SEM-EDX), and transmission electron microscopy (TEM), respectively. Results revealed that drought stress induced a notable increase in oxidative toxicity in G. macrophylla, as evidenced by elevated levels of hydrogen peroxide (H2O2), lipid peroxidation (MDA), enhanced antioxidative response, decreased plant photosynthetic function, and inhibited plant growth. Chloroplasts integrity with damaged membranes and excess osmiophilic granule were observed in the drought-stressed plants. Se supplementation notably recovered the stomatal morphology, anatomical structure damage, and chloroplast ultrastructure of G. macrophylla leaves caused by drought exposure. Exogenous Se application markedly enhanced SPAD, photosynthetic stomatal exchange parameters, and photosystem II activity. Se supplementation significantly promoted the activities of superoxide dismutase (SOD), ascorbate peroxidase (APX), and catalase (CAT), while reducing levels of MDA, superoxide anion (O2-.) and H2O2, and improving membrane integrity. Furthermore, the ameliorative effects of Se were also suggested by increased contents of osmotic substances (soluble sugar and proline), boosted content of gentiopicroside and loganinic acid in roots, and alleviated the inhibition in plant growth and biomass. Fourier transform infrared (FTIR) analysis of Se-treated G. macrophylla roots under drought stress demonstrated that Se-stimulated metabolites including O-H, C-H, N-H, C-N, and CO functional groups, were involved in resisting drought stress. Correlation analysis indicated an obvious negative correlation between growth parameters and MDA, O2-. and H2O2 content, while a positive correlation with photosynthetic gas exchange parameters. Principal component analysis (PCA) results explained the total variance into two principal components contributing the maximum (93.50 %) among the drought exposure with or without Se due to the various experiment indexes. In conclusion, Se exerts beneficial properties on drought-induced detrimental effects in G. macrophylla by relieving oxidative stress, improving photosynthesis indexes, PSII activity, regulating anatomical changes, altering levels of gentiopicroside and loganinic acid, and promoting growth of drought-stressed G. macrophylla.

Possible enrichment process of Cd in the Se-rich soil area of Lanshan District, Shandong Province, China.

High cadmium (Cd) concentrations widely occured in selenium (Se)-rich soils, which has been an important obstacle in the usage of Se-rich soils. There is still no special information detailing the enrichment process and mechanism of Cd in Se-rich soils. 4474 soils and 21 rocks in Lanshan District were sampled to detect its enrichment process. The surface soils have Cd concentrations of 0.01-9.41 mg·kg-1 (an average of 0.16 mg·kg-1). The soil Cd concentrations were significantly correlated with soil Se concentrations. The relatively higher-Cd surface soils are distributed in Lower-middle Ordovician carbonate areas with Se-rich soils and Quaternary areas with typical anthropic activities. Surface soils in Ordovician carbonate area have the highest Cd concentrations. Soil Cd concentrations are significantly correlated with sulfophil elements (Zinc (Zn), Copper (Cu), Molybdenum (Mo), Lead (Pb) and Arsenic (As) etc.), Ca (Calcium) concentrations and soil organic carbon (SOC). The soil and rock samples from different geological units also confirmed soil Cd concentrations developing from Ordovician carbonates were higher than those from other rocks. The results indicate the soil Cd concentrations were the complex consequences of bedrock, soil-forming processes and anthropogenic activities. Higher Ca concentrations and more reduction environments result in high-Cd bedrock. CaCO3 leaching and alkaline pH, which are the special soil-forming process of carbonates, enrich Cd in soils. Agricultural and industrial activities also affect soil Cd concentrations. An enrichment model of Cd in Se-rich soils is forwarded.

Effects of selenium enrichment on fermentation characteristics, selenium content and microbial community of alfalfa silage.

BACKGROUND: Selenium is essential for livestock and human health. The traditional way of adding selenium to livestock diets has limitations, and there is a growing trend to provide livestock with a safe and efficient source of selenium through selenium-enriched pasture. Therefore, this study was conducted to investigate the effects of selenium enrichment on fermentation characteristics, selenium content, selenium morphology, microbial community and in vitro digestion of silage alfalfa by using unenriched (CK) and selenium-enriched (Se) alfalfa as raw material for silage. RESULTS: In this study, selenium enrichment significantly increased crude protein, soluble carbohydrate, total selenium, and organic selenium contents of alfalfa silage fresh and post-silage samples, and it significantly decreased neutral detergent fiber and acid detergent fiber contents (p < 0.05). Selenium enrichment altered the form of selenium in plants, mainly in the form of SeMet and SeMeCys, which were significantly higher than that of CK (p < 0.05). Selenium enrichment could significantly increase the lactic acid content, reduce the pH value, change the diversity of bacterial community, promote the growth of beneficial bacteria such as Lactiplantibacillus and inhibit the growth of harmful bacteria such as Pantoea, so as to improve the fermentation quality of silage. The in vitro digestibility of dry matter (IVDMD), in vitro digestibility of acid detergent fibers (IVADFD) and in vitro digestibility of acid detergent fibers (IVNDFD) of silage after selenium enrichment were significantly higher than those of CK (p < 0.05). CONCLUSION: This study showed that the presence of selenium could regulate the structure of the alfalfa silage bacterial community and improve alfalfa silage fermentation quality. Selenium enrichment measures can change the morphology of selenium in alfalfa silage products, thus promoting the conversion of organic selenium.

Serum selenium and fasting blood glucose: a cross-sectional study in women of different menopause status.

BACKGROUND: This cross-sectional study aims to explore whether there exists an interaction between selenium and menopause concerning type 2 diabetes (T2D) prevalence and its related indicators such as fasting blood glucose (FBG) and homeostasis model assessment of insulin resistance (HOMA-IR). METHODS: 150 women aged 35-60 years old were finally analyzed in this study. Multivariate linear or logistic regression modeling was conducted to explore the association of selenium and the prevalence of T2D besides its related indicators. Subgroup analyses were conducted based on menopause status to assess the potential impact on the relationship. RESULTS: In the fully adjusted model, serum selenium was positively associated with FBG (ß: 0.03, CI: 0.01-0.05) and the prevalence of T2D (OR: 1.04, CI: 1.00-1.08). After stratifying the data by menopause status, compared with the postmenopausal women group, as the serum selenium concentrations increased, the FBG concentrations were significantly higher in the premenopausal women group (p for interaction = 0.0020). CONCLUSIONS: The present study found serum selenium was positively associated with FBG and the prevalence of T2D. Furthermore, the relationship between serum selenium and FBG was different in the premenopausal and postmenopausal women. More studies are still needed in the future to verify the relationship as well as to explore the specific mechanisms.

Selenium nanoparticles enhance mucosal immunity against Mycobacterium bovis infection.

Selenium nanoparticles (SeNPs) enhance the immune response as adjuvants, increasing the efficacy of viral vaccines, including those for COVID-19. However, the efficiency of mucosal SeNPs in boosting vaccine-induced protective immunity against tuberculosis remains unclear. Therefore, this study aims to investigate whether the combination of SeNPs with the AH antigen (Ag85A-HspX) can boost respiratory mucosal immunity and thereby enhance the protective effects against tuberculosis. We synthesized SeNPs and assessed their impact on the immune response and protection against Mycobacterium bovis (M. bovis) as a mucosal adjuvant in mice, administered intranasally at a dose of 20 µg. SeNPs outperformed polyinosinic-polycytidylic acid (Poly IC) in stimulating the maturation of bone marrow-derived dendritic cells (BMDCs), which enhanced antigen presentation. SeNPs significantly activated and proliferated tissue-resident memory T cells (TRMs) and effector CD4+ T cells in the lungs. The vaccines elicited specific antibody responses in the respiratory tract and stimulated systemic Th1 and Th17 immune responses. Immunization with AH and SeNPs led to higher levels of mucosal secretory IgA in bronchoalveolar lavage fluid (BALF) and secretory IL-17 in splenocytes. Moreover, SeNPs immunized mice showed reduced M. bovis infection loads and inflammatory lesions in the lungs post-challenge. Notably, immunization with AH and SeNPs significantly reduced bacterial load in the lungs, achieving the lowest levels compared to all other tested groups. This study calls for pre-clinical investigation of AHB-SeNPs as an anti-bovine tuberculosis vaccine and for exploring its human vaccine potential, which is anticipated to aid in the development of innovative vaccines or adjuvants.

Selenium represses microRNA-202-5p/MICU1 aixs to attenuate mercuric chloride-induced kidney ferroptosis.

Mercuric chloride (HgCl2) is a nephrotoxic contaminant that is widely present in the environment. Selenium (Se) can effectively antagonize the biological toxicity caused by heavy metals. Here, in vivo and in vitro models of Se antagonism to HgCl2-induced nephrotoxicity in chickens were established, with the aim of exploring the specific mechanism. Morphological observation and kidney function analysis showed that Se alleviated HgCl2-induced kidney tissue injury and cytotoxicity. The results showed that ferroptosis was the primary mechanism for the toxicity of HgCl2, as indicated by iron overload and lipid peroxidation. On the one hand, Se significantly prevented HgCl2-induced iron overload. On the other hand, Se alleviated the intracellular reactive oxygen species (ROS) levels caused by HgCl2. Subsequently, we focused on the sources of ROS during HgCl2-induced ferroptosis. Mechanically, Se reduced ROS overproduction induced by HgCl2 through mitochondrial calcium uniporter (MCU)/mitochondrial calcium uptake 1 (MICU1)-mediated mitochondrial calcium ion (Ca2+) overload. Furthermore, a dual luciferase reporter assay demonstrated that MICU1 was the direct target of miR-202-5p. Overall, Se represses miR-202-5p/MICU1 axis to attenuate HgCl2-induced kidney ferroptosis.

Investigation of Doehlert matrix conception in novel intrinsically conducting polymers based on selenium nanoparticles for wastewater treatment: Synthesis, characterization, kinetic and chemometric study.

The synthesis of robust intrinsically conducting polymers (ICPs) based on nanoparticles is becoming increasingly attractive to the research community due to the unique properties of these nanocomposites. Indeed, as organic semiconductors, ICPs combine both polymer and metal properties in a single structure. This study presents an innovative approach in which the Doehlert Matrix (DM) is applied to a novel ICP nanocomposite based on polyaniline (Pani) coupled with selenium (Se) loaded mesoporous titania (TiO2) for wastewater treatment by photocatalysis. It includes both the elaboration routes of ICP nanocomposites, characterization of materials by X-ray diffraction (XRD), BET analysis, thermogravimetric analysis (TGA), RAMAN spectroscopy and Fourier transform infrared spectroscopy (FTIR) and photodegradation of methylene blue (MB) as a representative of dye pollutant. In addition, the photocatalytic process has been optimized by a novel DM conception. The effect of the pH of the solution, the catalyst dosage and the initial pollutant concentration was investigated. The optimum conditions were found to be: initial MB concentration of 15 mg/L, the catalyst dosage of 69 mg and pH of 9.6 with an operating time of 75 min, with a coefficient of determination R2 equal to 0.9985. The removal efficiency of BM was close to 97 %. The study shows that the new ICP nanocomposites improve the photocatalytic efficiency compared to pure titania and/or pure Pani. In addition, as the ternary Pani-Se-TiO2 nanocomposite could be obtained from a low-cost synthesis, it is a very promising material for use in wastewater treatment.

Effects of different rootstocks grafting on selenium accumulation in Cyphomandra betacea Sendt. seedlings under selenium-contaminated soil.

The effects of rootstocks tomato (Solanum lycopersicum L.), eggplant (Solanum melongena L.), and nightshade (Solanum nigrum L.) grafting on the growth and selenium (Se) accumulation of Cyphomandra betacea Sendt. seedlings were studied to identify the most suitable rootstock for increasing Se uptake of fruit trees grown in Se-contaminated soil. The rootstocks of tomato, eggplant, and nightshade grafting increased the scion biomass of C. betacea seedlings by 146.1%, 23.2%, and 94.5%, respectively, compared with the un-grafted seedlings. Moreover, tomato, eggplant, and nightshade rootstocks grafting increased the photosynthesis, superoxide dismutase activity, and peroxidase activity, while reducing the catalase activity and soluble protein content of C. betacea seedlings. Although all three rootstocks grafting decreased Se contents in rootstock roots and stems, only nightshade rootstock grafting increased Se content in the scions of C. betacea seedlings. Notably, root biomass, catalase activity, soluble protein content, rootstock root Se content, and rootstock stem Se content were closely related to the scion Se content. These findings suggest that only grafting onto nightshade rootstock significantly enhances Se uptake in C. betacea, whereas tomato and eggplant rootstocks grafting have no effect on Se uptake.

This study shows that under selenium (Se)-contaminated soil conditions, tomato, eggplant, and nightshade rootstocks can promote the growth of C. betacea seedlings and improve their stress resistance. The nightshade rootstock stands out for its ability to promote Se uptake in C. betacea seedlings, suggesting its suitability as a promising rootstock to enhance both growth and Se uptake in C. betacea.

The Promising Role of Selenium and Yeast in the Fight Against Protein Amyloidosis.

In recent years, increasing attention has been paid to research on diseases related to the deposition of misfolded proteins (amyloids) in various organs. Moreover, modern scientists emphasise the importance of selenium as a bioelement necessary for the proper functioning of living organisms. The inorganic form of selenium-sodium selenite (redox-active)-can prevent the formation of an insoluble polymer in proteins. It is very important to undertake tasks aimed at understanding the mechanisms of action of this element in inhibiting the formation of various types of amyloid. Furthermore, yeast cells play an important role in this matter as a eukaryotic model organism, which is intensively used in molecular research on protein amyloidosis. Due to the lack of appropriate treatment in the general population, the problem of amyloidosis remains unsolved. This extracellular accumulation of amyloid is one of the main factors responsible for the occurrence of Alzheimer's disease. The review presented here contains scientific information discussing a brief description of the possibility of amyloid formation in cells and the use of selenium as a factor preventing the formation of these protein aggregates. Recent studies have shown that the yeast model can be successfully used as a eukaryotic organism in biotechnological research aimed at understanding the essence of the entire amyloidosis process. Understanding the mechanisms that regulate the reaction of yeast to selenium and the phenomenon of amyloidosis is important in the aetiology and pathogenesis of various disease states. Therefore, it is imperative to conduct further research and analysis aimed at explaining and confirming the role of selenium in the processes of protein misfolding disorders. The rest of the article discusses the characteristics of food protein amyloidosis and their use in the food industry. During such tests, their toxicity is checked because not all food proteins can produce amyloid that is toxic to cells. It should also be noted that a moderate diet is beneficial for the corresponding disease relief caused by amyloidosis.