Selenium, Selenoproteins, and Immunity

Influence of Select Dietary Trace Minerals and their Levels on Growth Performance, Nutrient Utilization and Minerals Balance in Male Goats

A study was conducted on eighteen male goats to evaluate the effect of incremental levels of select dietary trace minerals on growth performance, nutrient utilization and minerals balance. Animals (16.65 ± 0.53 kg average BW) were randomly divided into three groups and fed a basal diet to meet the requirement of all the nutrients except select trace minerals for 60 days. Groups were T1 (0.204 ppm Se, 35.29 ppm Zn, 7.37 ppm Cu, 39.79 ppm Mn), T2 (0.504 ppm Se, 55.29 ppm Zn, 17.37 ppm Cu, 59.79 ppm Mn), and T3 (0.804 ppm Se, 75.29 ppm Zn, 27.37 ppm Cu, 79.79 ppm Mn). Daily dry matter intake (DMI) (% BW) was lower (P < 0.05) in T3 as compared to other groups however, average daily gain (ADG) in body weight (P = 0.113) and feed: gain ratio (P = 0.102) showed subtle improvement in T2 and T3 groups. Feeding of higher levels of select trace minerals did not affect the intake and digestibility of nutrients, or plane of nutrition, however, the digestibility of non-fiber carbohydrates (NFC) increased (P = 0.004) in T2 and T3 groups than T1. The balance of N, Ca, P and Cu did not differ among the groups but balance of Zn, Mn and Se increased in T2 and T3 groups than T1 group. It is concluded that feeding higher levels of Zn (75.29 ppm), Cu (27.37 ppm), Mn (79.79 ppm) and Se (0.804 ppm) in combination, improved NFC digestibility, retention of Zn, Mn and Se and had subtle beneficial effects on the growth performance of male goats.

The impact of the Mediterranean diet on immune function in older adults

Diet is one of the lifestyle factors that is most amenable to intervention, and has a substantial effect on the potential for successful aging and mitigation of the risk of disease. Good nutrition is a pillar of healthy aging, and a large body of evidence attests to the benefits of the Mediterranean diet on the quality of the aging process. The Mediterranean diet comprises a wide range of nutrients which, both individually and collectively, exert positive effects on immunity, in large part mediated by the gut microbiota. In this article, we review the effect of the Mediterranean diet on immunity, and how its beneficial effects are mediated by the gut microbiota. We review the effects of certain key components of the Mediterranean dietary pattern, including vitamins, zinc, selenium, and polyphenols. Overall, the existing body of evidence convincingly demonstrates that the Mediterreanean diet affects immune health by maintaining a healthy body weight and reducing the risk of metabolic and cardiovascular diseases; by reducing inflammation and by promoting a healthy gut microbiota profile.

Seleno-amino Acid Metabolism Reshapes the Tumor Microenvironment: from Cytotoxicity to Immunotherapy

Selenium (Se) is an essential trace element for biological processes. Seleno-amino acids (Se-AAs), known as the organic forms of Se, and their metabolic reprogramming have been increasingly recognized to regulate antioxidant defense, enzyme activity, and tumorigenesis. Therefore, there is emerging interest in exploring the potential application of Se-AAs in antitumor therapy. In addition to playing a vital role in inhibiting tumor growth, accumulating evidence has revealed that Se-AA metabolism could reshape the tumor microenvironment (TME) and enhance immunotherapy responses. This review presents a comprehensive overview of the current progress in multifunctional Se-AAs for antitumor treatment, with a particular emphasis on elucidating the crosstalk between Se-AA metabolism and various cell types in the TME, including tumor cells, T cells, macrophages, and natural killer cells. Furthermore, novel applications integrating Se-AAs are also discussed alongside prospects to provide new insights into this emerging field.

Microflora structure and functional capacity in Tibetan kefir grains and selenium-enriched Tibetan kefir grains: A metagenomic analysis

Tibetan kefir grains (TKGs) are a complex protein-lipid-polysaccharide matrix composed of various microorganisms. Microorganisms have the benefit of being effective, secure, and controllable when used for selenium enrichment. In this study, selenium-enriched Tibetan kefir grains (Se-TKGs) were made, and the microbiology composition was analyzed through a metagenomic analysis, to explore the influence of selenium enrichment. The microbial composition of TKGs and Se-TKGs, as well as the probiotic species, quorum sensing system (QS) and functional genes were compared and evaluated. Lactobacillus kefiranofaciens was the most abundant microbial species in both communities. Compared with TKGs, Se-TKGs had a much higher relative abundance of acetic acid bacteria. Lactobacillus helveticus was the most common probiotic species both in TKGs and Se-TKGs. Probiotics with antibacterial and anti-inflammatory properties were more abundant in Se-TKGs. QS analysis revealed that Se-TKGs contained more QS system-associated genes than TKGs. Moreover, Kyoto Encyclopedia of Genes and Genomes analysis revealed that the pathway for human disease ko01501 had the greatest relative abundance in both TKGs and Se-TKGs. Compared with TKGs, Se-TKGs demonstrated a greater relative abundance of different drug resistance-related metabolic pathways. Additionally, linear discriminant analysis effect size was used to examine the biomarkers responsible for the difference between the two groups. In this study, we focused on the microbiological structure of TKGs and Se-TKGs, with the aim of establishing a foundation for a more thorough investigation of Se-TKGs and providing a basis for exploring potential future use.

Nitrate reductase involves in selenite reduction in Rahnella aquatilis HX2 and the characterization and anticancer activity of the biogenic selenium nanoparticles

BACKGROUND

Biogenic selenium nanoparticles (SeNPs) show numerous advantages including their high stability, low toxicity, and high bioactivity. While metabolism of SeNPs remains not well studied and need more investigation to reveal the process.

PURPOSE

The objective of the study was to investigate the relationship between nitrate reductase and selenite reduction in Rahnella aquatilis HX2, characterize the properties of HX2 produced SeNPs, and explore their potential applications, particularly their anticancer activity.

PROCEDURES

Selenium species were measured by high-performance liquid chromatography coupled to inductively coupled plasma - Mass spectrometry (HPLC-ICP-MS). Transcription level of nitrate reductase was determined by Real-time quantitative PCR. Morphology, particle size, crystal structure and surface chemistry of SeNPs were determined by electron microscopy, dynamic light scattering method, Raman scattering, X-ray photoelectron spectroscopy, respectively. Anti cancer cell activity was measured by CCK-8 assay.

MAIN FINDINGS

SeNP production in R. aquatilis HX2 was correlated with the cell growth. The products of selenite reduction in HX2 detected by HPLC-ICP-MS included SeNPs, selenocysteine (SeCys), Se-Methylselenocysteine (MeSeCys), and 7 unknown compounds. Nitrate addition experiments suggested the involvement of nitrate reductase in selenite reduction in HX2. Both the cellular membrane and cytoplasm of HX2 exhibited selenite-reducing ability, indicating that membrane-associated nitrate reductase was not the sole selenite reductase in HX2. Characterization of the biogenic SeNPs revealed a spherical morphology and amorphous structure of them. Surface chemistry analysis implicated the binding of extracellular polymeric substances to the biogenic SeNPs, and the presence of Se0, Se2-, and electron-rich Se atoms on the surface of SeNPs. Finally, the IC50 values of the biogenic SeNPs were 36.49 μM for HepG2 and 3.70 μM for HeLa cells.

CONCLUSIONS

The study first revealed that the nitrate reductase is involving in selenite reduction in R. aquatilis HX2. The biogenic SeNPs coordinated with organic substances in the surface. And SeNPs produced by R. aquatilis HX2 showed excellent anticancer activities on HepG2 and HeLa cells.

The influence of serum selenium in differential epigenetic and transcriptional regulation of CPT1B gene in women with obesity

INTRODUCTION

The increasing prevalence of obesity has become a major health problem worldwide. The causes of obesity are multifactorial and could be influenced by dietary patterns and genetic factors. Obesity has been associated with a decrease in micronutrient intake and consequently decreased blood concentrations. Selenium is an essential micronutrient for human health, and its metabolism could be affected by obesity, especially severe obesity. This study aimed to identify differential methylation genes associated with serum selenium concentration in women with and without obesity.

METHODOLOGY

Thirty-four patients were enrolled in the study and divided into two groups: Obese (Ob) n = 20 and Non-Obese (NOb) n = 14, according to the Body Mass Index (BMI). Anthropometry, body composition, serum selenium, selenium intake, and biochemical parameters were evaluated. DNA extraction and bisulfite conversion were performed to hybridize the samples on the 450k Methylation Chip Infinium Beadchip (Illumina). Bioinformatics analysis was performed using the R program and the Champ package. The differentially methylated regions (DMRs) were identified using the Bumphunter method. In addition, logarithmic conversion was performed for the analysis of serum selenium and methylation.

RESULTS

In the Ob group, the body weight, BMI, fat mass, and free fat mass were higher than in the NOb group, as expected. Interestingly, the serum selenium was lower in the Ob than in the NOb group without differences in selenium intake. One DMR corresponding to the CPT1B gene, involved in lipid oxidation, was related to selenium levels. This region was hypermethylated in the Ob group, indicating that the intersection between selenium deficiency and hypermethylation could influence the expression of the CPT1B gene. The transcriptional analysis confirmed the lower expression of the CPT1B gene in the Ob group.

CONCLUSION

Studies connecting epigenetics to environmental factors could offer insights into the mechanisms involving the expression of genes related to obesity and its comorbidities. Here we demonstrated that the mineral selenium might play an essential role in lipid oxidation via epigenetic and transcriptional regulation of the CPT1B gene in obesity.

Effects of replacing Na selenite in laying hen feed with selenized glucose on production performance, egg quality, egg selenium content, microbial population, immunological response, antioxidant enzymes, and fatty acid composition

This study aimed to explore the effects of selenized glucose (SeGlu) and Na selenite supplementation on various aspects of laying hens such as production performance, egg quality, egg Se concentration, microbial population, antioxidant enzymes activity, immunological response, and yolk fatty acid profile. Using a 2 × 2 factorial design, 168 laying hens at 27-wk of age were randomly divided into 4 treatment groups with 7 replications. Se source (Na selenite and SeGlu) and Se level (0.3 and 0.6 mg/kg) were used as treatments. When 0.3 mg SeGlu/kg was compared to 0.3 mg Na selenite/kg, the interaction findings revealed that 0.3 mg SeGlu/kg increased egg production percent and shell ash (P < 0.05). When compared to 0.3 mg Na selenite/kg, dietary supplementation with 0.3 and 0.6 mg SeGlu/kg resulted in an increase in albumen height, Haugh unit, and yolk color of fresh eggs (P < 0.05). SeGlu enhanced albumen height, Haugh unit, shell thickness (P < 0.01), albumen index, yolk share, specific gravity, shell ash (P < 0.05) of fresh eggs and shell thickness (P < 0.05) of stored eggs as compared to Na selenite. The interaction showed that 0.6 mg SeGlu/kg enhanced yolk Se concentration while decreasing malondialdehyde levels in fresh egg yolk (P < 0.05). SeGlu enhanced Se concentration in albumen and glutathione peroxidase activity in plasma (P < 0.05) as compared to Na selenite. 0.6 mg Se/kg increased lactic acid bacteria, antibody response to sheep red blood cells, and lowered ∑n-6 PUFA/ ∑n-3 PUFA ratio (P < 0.05). As a result, adding SeGlu to the feed of laying hens enhanced egg production, egg quality, egg Se concentration, fresh yolk lipid oxidation, and glutathione peroxidase enzyme activity.

Selenium Nanoparticles: Revolutionizing Nutrient Enhancement in Aquaculture - A Review

Aquaculture, a cornerstone of global food production, confronts myriad challenges including disease outbreaks and environmental degradation. Achieving nutritionally balanced aquafeed is critical for sustainable production, prompting exploration into innovative solutions like selenium nanoparticles (SeNPs). SeNPs offer potent antimicrobial, antioxidant, and growth-promoting properties, bolstering gut immunity and digestive capacity in aquatic animals. Their high bioavailability and ability to traverse gut barriers make them promising candidates for aquafeed supplementation. This study investigates SeNPs as a cutting-edge solution to enhance nutrient supply in aquaculture, addressing key challenges while promoting environmental stewardship and food security. By synthesizing current research and highlighting future directions, this review provides valuable insights into sustainable aquaculture practices. SeNPs hold promise for revolutionizing aquaculture feed formulations, offering a pathway to improved production outcomes and environmental sustainability.

The Potential of Integrative Cancer Treatment Using Melatonin and the Challenge of Heterogeneity in Population-Based Studies: A Case Report of Colon Cancer and a Literature Review

Melatonin is a multifunctional hormone regulator that maintains homeostasis through circadian rhythms, and desynchronization of these rhythms can lead to gastrointestinal disorders and increase the risk of cancer. Preliminary clinical studies have shown that exogenous melatonin alleviates the harmful effects of anticancer therapy and improves quality of life, but the results are still inconclusive due to the heterogeneity of the studies. A personalized approach to testing clinical parameters and response to integrative treatment with nontoxic and bioavailable melatonin in patient-centered N-of-1 studies deserves greater attention. This clinical case of colon cancer analyzes and discusses the tumor pathology, the adverse effects of chemotherapy, and the dynamics of markers of inflammation (NLR, LMR, and PLR ratios), tumors (CEA, CA 19-9, and PSA), and hemostasis (D-dimer and activated partial thromboplastin time). The patient took melatonin during and after chemotherapy, nutrients (zinc, selenium, vitamin D, green tea, and taxifolin), and aspirin after chemotherapy. The patient's PSA levels decreased during CT combined with melatonin (19 mg/day), and melatonin normalized inflammatory markers and alleviated symptoms of polyneuropathy but did not help with thrombocytopenia. The results are analyzed and discussed in the context of the literature on oncostatic and systemic effects, alleviating therapy-mediated adverse effects, association with survival, and N-of-1 studies.

Biomarker and transcriptomics profiles of serum selenium concentrations in patients with heart failure are associated with immunoregulatory processes

BACKGROUND

Low selenium concentrations are associated with worse outcomes in heart failure (HF). However, the underlying pathophysiologic mechanisms remain incompletely understood. Therefore, we aimed to contrast serum selenium concentrations to blood biomarker and transcriptomic profiles in patients with HF.

METHODS

Circulating biomarkers, whole blood transcriptomics and serum selenium measurements in a cohort of 2328 patients with HF were utilized. Penalized linear regression and gene expression analysis were used to assess biomarker and transcriptomics profiles, respectively. As a proof-of-principle, potential causal effects of selenium on excreted cytokines concentrations were investigated using human peripheral blood mononuclear cells (PBMCs).

RESULTS

Mean selenium levels were 60.6 μg/L in Q1 and 122.0 μg/L in Q4. From 356 biomarkers and 20 clinical features, the penalized linear regression model yielded 44 variables with <5 % marginal false discovery rate as predictors of serum selenium. Biomarkers associated positively with selenium concentrations included: epidermal growth factor receptor (EGFR), IFN-gamma-R1, CD4, GDF15, and IL10. Biomarkers associated negatively with selenium concentrations included: PCSK9, TNFSF13, FGF21 and PAI. Additionally, 148 RNA transcripts were found differentially expressed between high and low selenium status (Padj.<0.05; log-fold-change<|0.25|). Enrichment analyses of the selected biomarkers and RNA transcripts identified similar enriched processes, including regulation processes of leukocyte differentiation and activation, as well as cytokines production. The mRNA expression of two selenoproteins (MSRB1 and GPX4) were strongly correlated with serum selenium, while GPX4, SELENOK, and SELENOS were associated with prognosis. In the in-vitro setting, PBMCs supplemented with selenium showed significantly lower abundance of several (pro-)inflammatory cytokines.

CONCLUSION

These data suggest that immunoregulation is an important mechanism through which selenium might have beneficial roles in HF. The beneficial effects of higher serum selenium concentrations are likely because of global immunomodulatory effects on the abundance of cytokines. MSRB1 and GPX4 are potential modulators of and should be pursued in future research.

SELENOK-dependent CD36 palmitoylation regulates microglial functions and Aβ phagocytosis

Amyloid-beta (Aβ) is a key factor in the onset and progression of Alzheimer's disease (AD). Selenium (Se) compounds show promise in AD treatment. Here, we revealed that selenoprotein K (SELENOK), a selenoprotein involved in immune regulation and potentially related to AD pathology, plays a critical role in microglial immune response, migration, and phagocytosis. In vivo and in vitro studies corroborated that SELENOK deficiency inhibits microglial Aβ phagocytosis, exacerbating cognitive deficits in 5xFAD mice, which are reversed by SELENOK overexpression. Mechanistically, SELENOK is involved in CD36 palmitoylation through DHHC6, regulating CD36 localization to microglial plasma membranes and thus impacting Aβ phagocytosis. CD36 palmitoylation was reduced in the brains of patients and mice with AD. Se supplementation promoted SELENOK expression and CD36 palmitoylation, enhancing microglial Aβ phagocytosis and mitigating AD progression. We have identified the regulatory mechanisms from Se-dependent selenoproteins to Aβ pathology, providing novel insights into potential therapeutic strategies involving Se and selenoproteins.

Effects of selenium nanoparticles produced by Lactobacillus acidophilus HN23 on lipid deposition in WRL68 cells

Selenium is an essential trace element for most organisms, protecting cells from oxidative damage caused by free radicals and serving as an adjunctive treatment for non-alcoholic fatty liver disease (NAFLD). In this study, We used the lactic acid bacterium Lactobacillus acidophilus HN23 to reduce tetra-valent sodium selenite into particulate matter, and analyzed it through inductively coupled plasma mass spectrometry (ICP-MS), scanning electron microscopy (SEM), X-ray diffraction energy dispersive spectrometry (EDS), and Fourier transform infrared spectroscopy (FTIR). We found that it consisted of selenium nanoparticles (SeNPs) with a mass composition of 65.8 % zero-valent selenium and some polysaccharide and polypeptide compounds, with particle sizes ranging from 60 to 300 nm. We also detected that SeNPs were much less toxic to cells than selenite. We further used free fatty acids (FFA)-induced WRL68 fatty liver cell model to study the therapeutic effect of SeNPs on NAFLD. The results show that SeNPs are more effective than selenite in reducing lipid deposition, increasing mitochondrial membrane potential (MMP) and antioxidant capacity of WRL68 cells, which is attributed to the chemical valence state of selenium and organic composition in SeNPs. In conclusion, SeNPs produced by probiotics L. acidophilus had the potential to alleviate NAFLD by reducing hepatocyte lipid deposition and oxidative damage. This study may open a new avenue for SeNPs drug development to treat NAFLD.

The beneficial and toxic effects of selenium on zebrafish. A systematic review of the literature

Selenium is an important and essential trace element in organisms, but its effects on organisms are also a "double-edged sword". Selenium deficiency or excess can endanger the health of humans and animals. In order to thoroughly understand the nutritional value and toxicity hazards of selenium, researchers have conducted many studies on the model animal zebrafish. However, there is a lack of induction and summary of relevant research on which selenium acts on zebrafish. This paper provides a review of the reported studies. Firstly, this article summarizes the benefits of selenium on zebrafish from three aspects: Promoting growth, Enhancing immune function and anti-tumor ability, Antagonizing some pollutants, such as mercury. Then, three aspects of selenium toxicity to zebrafish are introduced: nervous system and behavior, reproductive system and growth, and damage to some organs. This article also describes how different forms of selenium compounds have different effects on zebrafish health. Finally, prospects for future research directions are presented.

Selenomethionine Inhibits NF-κB-mediated Inflammatory Responses of Bovine Mammary Epithelial Cells Caused by Klebsiella pneumoniae by Increasing Autophagic Flux

Klebsiella pneumoniae (K. pneumoniae) is one of the major pathogens causing bovine clinical mastitis. Autophagy maintains cellular homeostasis and resists excessive inflammation in eukaryotic organisms. Selenomethionine (Se-Met) is commonly used as a source of selenium supplementation for dairy cows. This study aimed to investigate the effects of Se-Met on inflammatory responses mediated by nuclear factor-kappa B (NF-κB) through autophagy. We infected bovine mammary epithelial cell line (MAC-T) with K. pneumoniae and examined the expression of autophagy-related proteins and changes in autophagic vesicles, LC3 puncta, and autophagic flux at various intervals. The results showed that K. pneumoniae activated the early-stage autophagy of MAC-T cells. The levels of LC3-II, Beclin1, and ATG5, as well as the number of LC3 puncta and autophagic vesicles, increased after 2 h post-treatment. However, the late-stage autophagic flux was blocked. Furthermore, the effect of autophagy on NF-κB-mediated inflammation was investigated with different autophagy levels. The findings showed that enhanced autophagy inhibited the K. pneumoniae-induced inflammatory responses of MAC-T cells. The opposite results were found with the inhibition of autophagy. Finally, we examined the effect of Se-Met on NF-κB-mediated inflammation based on autophagy. The results indicated that Se-Met alleviated K. pneumoniae-induced autophagic flux blockage, inhibited NF-κB-mediated inflammation, and decreased the adhesion of K. pneumoniae to MAC-T cells. The inhibitory effect of Se-Met on NF-κB-mediated inflammation could be partially blocked by the autophagy inhibitor chloroquine (CQ). Overall, Se-Met attenuated K. pneumoniae-induced NF-κB-mediated inflammatory responses by enhancing autophagic flux.

The mechanism of selenium regulating the permeability of vascular endothelial cells through selenoprotein O

Vascular diseases, a leading cause of death in human, are strongly associated with pathological damage to blood vessels. The selenoprotein (Sel) have been reported to play important roles in vascular disease. However, the role of SelO in vascular disease has not been conclusively investigated. The present experiment was to investigate the regulatory mechanism of the effect of SelO on the permeability of vascular endothelial. The H.E staining, FITC-Dextran staining, Dil-AC-LDL staining and FITC-WGA staining showed that vascular structure was damaged, and intercellular junctions were disrupted with selenium (Se)-deficient. Immunohistochemistry, qPCR and Western blot revealed decreased expression of the adhesion plaque proteins vinculin, talin and paxillin, decreased expression of the vascular connectivity effector molecules connexin, claudin-1 and E-cadherin and increased expression of JAM-A and N-cadherin, as well as decreased expression of the ZO-1 signaling pathways ZO-1, Rock, rhoGEF, cingulin and MLC-2. In a screening of 24 Sel present in mice, SelO showed the most pronounced changes in vascular tissues, and a possible association between SelO and vascular intercellular junction effectors was determined using IBM SPSS Statistics 25. Silencing of SelO, vascular endothelial intercellular junction adverse effects present. The regulatory relationship between SelO and vascular endothelial intercellular junctions was determined. The results showed that Se deficiency lead to increased vascular endothelial permeability and vascular tissue damage by decreasing SelO expression, suggesting a possible role for SelO in regulating vascular endothelial permeability.

Selenium Yeast Alleviates Dextran Sulfate Sodium-Induced Chronic Colitis in Mice by Reducing Proinflammatory Cytokines and Regulating the Gut Microbiota and Their Metabolites

Background

Inflammatory bowel disease (IBD) is a chronic recurrent gastrointestinal inflammatory disease. Selenium has been reported to have therapeutic potential in IBD. Selenium yeast is a common selenium supplement that is convenient to access. This study explored the effect of selenium yeast on dextran sulfate sodium- (DSS-)induced chronic colitis in mice.

Methods

Mice were randomly divided into four groups: the control group, selenium yeast group, chronic colitis group, and chronic colitis+selenium yeast group (n=6). Mice were killed on the 26th day. The disease activity index (DAI) score and histological damage score were calculated. Cytokines, serum selenium, colonic tissue selenium, gut microbiota and their metabolites short-chain fatty acids (SCFAs) were evaluated.

Results

Selenium yeast lowered IL-1β, IL-6, TNF-α, IL-17A, IL-22 and IFN-γ (P<0.05). In addition, selenium yeast significantly elevated Turicibacter, Bifidobacterium, Allobaculum, Prevotella, Halomonas, Adlercreutzia (P<0.05), and butyric acid (P<0.05).

Conclusion

Selenium yeast could improve DSS-induced chronic colitis in mice by regulating cytokines, gut microbiota and their metabolites.

Serum Selenium Concentration as a Potential Diagnostic Marker for Early-Stage Colorectal Cancer: A Comparative Study

BACKGROUND Selenium deficiency is an established risk factor for colorectal cancer. The aim of the present study was to determine selenium levels in blood samples obtained from colorectal cancer patients compared with the levels of this element in the blood of patients who had undergone hernia repair and cholecystectomy. MATERIAL AND METHODS The study group consisted of 49 patients diagnosed with colorectal cancer at our institution. The comparison group consisted of 29 and 26 patients undergoing hernia repair and cholecystectomy, respectively. The histological staging level was evaluated on a 4-grade scale. Serum selenium concentration was quantified by inductively coupled mass spectrometry using methane to reduce polyatomic interference. RESULTS Colorectal cancer patients had significantly lower serum selenium concentration than the comparison patients (67.24±15.55 μg/L vs 78.81±12.93 μg/L; P<0.001), and selenium concentration was below the reference range in a high percentage of colorectal cancer patients. However, among the colorectal cancer patients, no significant difference in cancer grading was observed according to selenium concentration (P=0.235). Serum selenium concentration in the patients was evaluated on the basis of 5 independent variables (R=0.6250): age (P=0.011), number of leukocytes (P=0.010), family history of cancer (P=0.045), dietary supplements (P=0.023), and exposure to chemical factors (P=0.057). CONCLUSIONS This study supports findings from previous studies that low serum selenium levels are associated with colorectal cancer and that selenium deficiency may be a risk factor for colorectal cancer.

Preoperative serum selenium predicts acute kidney injury after adult cardiac surgery

BACKGROUND

The relationship between serum selenium (Se) and acute kidney injury after adult cardiac surgery (CSA-AKI) remains controversial. This study aimed to investigate the association of preoperative Se level with incident CSA-AKI.

METHOD AND RESULTS

A retrospective cohort study was conducted on patients who underwent cardiac surgery. The primary outcome was incident CSA-AKI. Multivariable logistic regression models and natural cubic splines were used to estimate the association of Se levels and primary outcome. A total of 453 patient with a mean age of 62.97 years were included. Among all patients, 159 (35.1%) incident cases of CSA-AKI were identified. The level of preoperative Se concentration in patients with CSA-AKI was significant lower than that in patients without CSA-AKI. The higher preoperative Se level was significantly associated with decreased risk of CSA-AKI (adjusted OR 0.91, 95% CI: 0.87-0.99). Dose-response relationship curve revealed a nearly L-shape correlation between serum Se selenium levels and incident CSA-AKI.

CONCLUSION

Our study suggested that a higher level of serum Se was significantly associated with lower risk of CSA-AKI. Further prospective studies are needed to clarify the causal relationship between serum Se level and incident CSA-AKI.

Effects of various selenium-enriched yeasts, selenomethionine, and nanoselenium on production performance, quality, and antioxidant capacity in laying hens

This study aimed to compare the effects of various selenium (Se) sources (2 mg/kg) on the performance, quality, and antioxidant capacity of laying hens as well as the Se content in their eggs and blood. We selected 720 34-wk-old Lohmann pink-shell laying hens were randomly assigned into 6 groups and fed a basal diet (control) or a basal diet supplemented with various Se sources (Se-enriched yeast, SY-A, SY-C, SY-N; selenomethionine SM, nano-Se SN) for 16 wk. There were 10 replicates of 120 hens per group. Dietary Se supplementation increased the egg production rate of all laying hens. Egg and serum Se deposition was highest in the SM group. Yolk color scores of SY-A and SY-N groups were significantly lower than those of other groups (P < 0.01). The protein height and Haugh unit were significantly lower in the SN group than in the other groups (P < 0.05). The yolk height was significantly higher in the SN and SY-N groups than in the SY-A group (P < 0.05). Dietary supplementation of selenium can improve the antioxidant capacity of laying hens. The SOD content of SM group was significantly lower than that of SY-A and SN group (P < 0.05). The malondialdehyde (MDA) content was significantly higher in the SM group than in the SY-A group (P < 0.05). The present work empirically demonstrated that the production performance of laying hens supplemented with 2 mg/kg Se was superior to that of the hens receiving only a basal diet. The SY-C group exhibited the best production performance, the SY-A group had the highest antioxidant capacity, and the SM group produced eggs with the highest level of Se enrichment.

An integrative pan-cancer bioinformatics analysis of MSRB1 and its association with tumor immune microenvironment, prognosis, and immunotherapy

Methionine sulfoxide reductase B1 (MSRB1) is involved in the development and immune regulation of multiple tumors. However, the role of MSRB1 in the tumor microenvironment and its potential as a therapeutic target remain largely unknown. In this study, MSRB1 expression patterns were evaluated using pan-cancer RNA sequencing data from multiple cell lines, tissues, and single cells. The pan-cancer prognostic role of MSRB1 was assessed and the association between MSRB1 expression and certain cancer characteristics was analyzed. We showed that MSRB1 expression levels were increased in several types of cancer (P < 0.05) and in certain cell types (macrophages, dendritic cells, and malignant tumor cells). The upregulation of MSRB1 expression was due to DNA copy number amplification. Furthermore, MSRB1 was significantly associated with the activation of immune pathways (P < 0.05, NES > 0), immune cell infiltration, and expression of immune checkpoint molecules. In addition, high expression of MSRB1 was found in a series of in vivo and in vitro immunotherapy response models (P < 0.05), and showed resistance to most targeted drugs. Our results indicated that MSRB1 may regulate the tumor immune microenvironment through an immunoresponse and potentially influence cancer development. This could make it a promising predictive biomarker and therapeutic target for precise tumor immunotherapy.

Ultrathin 2D As2Se3 Nanosheets for Photothermal-Triggered Cancer Immunotherapy

Arsenic trioxide (As2O3) has achieved groundbreaking success in the treatment of acute promyelocytic leukemia (APL). However, its toxic side effects seriously limit its therapeutic application in the treatment of solid tumors. To detoxify the severe side effects of arsenic, herein we synthesized innovative 2D ultrathin As2Se3 nanosheets (As2Se3 NSs) with synergistic photothermal-triggered immunotherapy effects. As2Se3 NSs are biocompatible and biodegradable under physiological conditions and can release As(III) and Se(0). Furthermore, selenium increases the immunomodulatory efficacy of arsenic treatments, facilitating reprogramming of the tumor microenvironment by As2Se3 NSs by enhancing the infiltration of natural killer cells and effector tumor-specific CD8+ T cells. The synergistic combination of photothermal therapy and immunotherapy driven by As2Se3 NSs via a simple but effective all-in-one strategy achieved efficient anticancer effects, addressing the key limitations of As2O3 for solid tumor treatment. This work demonstrates not only the great potential of selenium for detoxifying arsenic but also the application of 2D As2Se3 nanosheets for cancer therapy.

Current Trends on the Involvement of Zinc, Copper, and Selenium in the Process of Hepatocarcinogenesis

Numerous nutritional factors increase the risk of hepatocellular carcinoma (HCC) development. The dysregulation of zinc, copper, and selenium homeostasis is associated with the occurrence of HCC. The impairment of the homeostasis of these essential trace elements results in oxidative stress, DNA damage, cell cycle progression, and angiogenesis, finally leading to hepatocarcinogenesis. These essential trace elements can affect the microenvironment in HCC. The carrier proteins for zinc and copper and selenium-containing enzymes play important roles in the prevention or progression of HCC. These trace elements enhance or alleviate the chemosensitivity of anticancer agents in patients with HCC. The zinc, copper, or selenium may affect the homeostasis of other trace elements with each other. Novel types of cell death including ferropotosis and cupropotosis are also associated with hepatocarcinogenesis. Therapeutic strategies for HCC that target these carrier proteins for zinc and copper or selenium-containing enzymes have been developed in in vitro and in vivo studies. The use of zinc-, copper- or selenium-nanoparticles has been considered as novel therapeutic agents for HCC. These results indicate that zinc, copper, and selenium may become promising therapeutic targets in patients with HCC. The clinical application of these agents is an urgent unmet requirement. This review article highlights the correlation between the dysregulation of the homeostasis of these essential trace elements and the development of HCC and summarizes the current trends on the roles of these essential trace elements in the pathogenesis of hepatocarcinogenesis.

Structure characterization and antioxidant activity of abalone visceral peptides-selenium in vitro

Peptide-selenium chelate is widely regarded as one of the best selenium supplements for relieving selenium deficiency. In this study, abalone visceral peptides (AVP) was used to prepare a new type of peptides-selenium chelate to develop an organic selenium supplement with antioxidant activity. AVP prepared by alcalase exhibited the highest selenium-chelating ability. UV-visible spectroscopy, fluorescence spectroscopy, Fourier transform infrared spectroscopy and other structural analysis showed that selenium was mainly bound to the functional groups of -NH, -OH, -CH, CC, CO, and CN bonds on AVP. The formation of AVP-selenium chelate enhanced thermal stability and generated a new crystal structure. The ABTS•+ and •OH scavenging activities of AVP-selenium chelate were increased after in vitro digestion than that of AVP. Conclusively, this study analyzed the chelating mechanism of AVP and selenium from a structural perspective, which would provide a theoretical basis for the development of new selenium supplements.

The selenium-independent phospholipid hydroperoxide glutathione peroxidase from Theobroma cacao (TcPHGPX) protects plant cells against damages and cell death

Proteins from the glutathione peroxidase (GPX) family, such as GPX4 or PHGPX in animals, are extensively studied for their antioxidant functions and apoptosis inhibition. GPXs can be selenium-independent or selenium-dependent, with selenium acting as a potential cofactor for GPX activity. However, the relationship of plant GPXs to these functions remains unclear. Recent research indicated an upregulation of Theobroma cacao phospholipid hydroperoxide glutathione peroxidase gene (TcPHGPX) expression during early witches' broom disease stages, suggesting the use of antioxidant mechanisms as a plant defense strategy to reduce disease progression. Witches' broom disease, caused by the hemibiotrophic fungus Moniliophthora perniciosa, induces cell death through elicitors like MpNEP2 in advanced infection stages. In this context, in silico and in vitro analyses of TcPHGPX's physicochemical and functional characteristics may elucidate its antioxidant potential and effects against cell death, enhancing understanding of plant GPXs and informing strategies to control witches' broom disease. Results indicated TcPHGPX interaction with selenium compounds, mainly sodium selenite, but without improving the protein function. Protein-protein interaction network suggested cacao GPXs association with glutathione and thioredoxin metabolism, engaging in pathways like signaling, peroxide detection for ABA pathway components, and anthocyanin transport. Tests on tobacco cells revealed that TcPHGPX reduced cell death, associated with decreased membrane damage and H2O2 production induced by MpNEP2. This study is the first functional analysis of TcPHGPX, contributing to knowledge about plant GPXs and supporting studies for witches' broom disease control.

Biofortification with selenium as an alternative to increase the total phenolic compounds in brassicas: a systematic review and meta-analysis

The ability of brassicas to accumulate selenium is crucial for their positive effects on health. Selenium improves the immune system and the antioxidant defenses. Selenium biofortification of brassicas has therefore been explored to increase dietary selenium intake in humans. However, the effects of selenium biofortification on bioactive compounds, mainly phenolic compounds, are not clear. So, this systematic review and meta-analysis aimed to answer the question 'What are effects of the biofortification of brassicas with selenium on total phenolic compounds?' Ten studies, which assessed the effect of selenium biofortification on total phenolic compounds, were selected for qualitative synthesis and four studies were included in the meta-analysis after a thorough literature review of the PubMed, Science Direct, and Web of Knowledge databases. The quality of the evidence ranged from high to moderate. The meta-analysis results indicated that the total phenolic compound content was significantly higher (P = 0.002) in the supplemented group but the results showed considerable heterogeneity (P < 0.00001, I2  = 97%) between studies. This systematic review and meta-analysis summarizes the effect of Se biofortification on the increase in the content of total phenolic compounds and it suggests that several factors can affect this relationship. © 2023 Society of Chemical Industry.

Heterotrophic Selenium Incorporation into Chlorella vulgaris K-01: Selenium Tolerance, Assimilation, and Removal through Microalgal Cells

Chlorella has been applied in the production of selenium (Se) enriched organic biomass. However, limited information exists regarding heterotrophic selenium tolerance and its incorporation into Chlorella. This study aimed to investigate the potential of using Chlorella vulgaris K-01 for selenium biotransformation. To assess the dose-response effect of Se stress on the strain, time-series growth curves were recorded, growth productivity parameters were calculated, and Gaussian process (GP) regression analysis was performed. The strain's carbon and energy metabolism were evaluated by measuring residual glucose in the medium. Characterization of different forms of intracellular Se and residual Se in the medium was conducted using inductively coupled plasma-mass spectrometry (ICP-MS) and inductively coupled plasma optical emission spectrometer (ICP-OES). The EC50 value for the strain in response to Se stress was 38.08 mg/L. The maximum biomass productivity was 0.26 g/L/d. GP regression analysis revealed that low-level Se treatment could increase the biomass accumulation and the carrying capacity of Chlorella vulgaris K-01 in a heterotrophic culture. The maximum organic Se in biomass was 154.00 μg/g DW. These findings lay the groundwork for understanding heterotrophic microalgal production of Se-containing nutraceuticals, offering valuable insights into Se tolerance, growth dynamics, and metabolic responses in Chlorella vulgaris K-01.

Selenium-SelK-GPX4 axis protects nucleus pulposus cells against mechanical overloading-induced ferroptosis and attenuates senescence of intervertebral disc

Intervertebral disc degeneration (IVDD) is one of the most prevalent spinal degenerative disorders and imposes places heavy medical and economic burdens on individuals and society. Mechanical overloading applied to the intervertebral disc (IVD) has been widely recognized as an important cause of IVDD. Mechanical overloading-induced chondrocyte ferroptosis was reported, but the potential association between ferroptosis and mechanical overloading remains to be illustrated in nucleus pulposus (NP) cells. In this study, we discovered that excessive mechanical loading induced ferroptosis and endoplasmic reticulum (ER) stress, which were detected by mitochondria and associated markers, by increasing the intracellular free Ca2+ level through the Piezo1 ion channel localized on the plasma membrane and ER membrane in NP cells. Besides, we proposed that intracellular free Ca2+ level elevation and the activation of ER stress are positive feedback processes that promote each other, consistent with the results that the level of ER stress in coccygeal discs of aged Piezo1-CKO mice were significantly lower than that of aged WT mice. Then, we confirmed that selenium supplementation decreased intracellular free Ca2+ level by mitigating ER stress through upregulating Selenoprotein K (SelK) expression. Besides, ferroptosis caused by the impaired production and function of Glutathione peroxidase 4 (GPX4) due to mechanical overloading-induced calcium overload could be improved by selenium supplementation through Se-GPX4 axis and Se-SelK axis in vivo and in vitro, eventually presenting the stabilization of the extracellular matrix (ECM). Our findings reveal the important role of ferroptosis in mechanical overloading-induced IVDD, and selenium supplementation promotes significance to attenuate ferroptosis and thus alleviates IVDD, which might provide insights into potential therapeutic interventions for IVDD.

Effects of selenoprotein extracts from Cardamine hupingshanensis on growth, selenium metabolism, antioxidant capacity, immunity and intestinal health in largemouth bass Micropterus salmoides

This study aimed to assess the impact of dietary selenoprotein extracts from Cardamine hupingshanensis (SePCH) on the growth, hematological parameters, selenium metabolism, immune responses, antioxidant capacities, inflammatory reactions and intestinal barrier functions in juvenile largemouth bass (Micropterus salmoides). The base diet was supplemented with four different concentrations of SePCH: 0.00, 0.30, 0.60 and 1.20 g/Kg (actual selenium contents: 0.37, 0.59, 0.84 and 1.30 mg/kg). These concentrations were used to formulate four isonitrogenous and isoenergetic diets for juvenile largemouth bass during a 60-day culture period. Adequate dietary SePCH (0.60 and 1.20 g/Kg) significantly increased weight gain and daily growth rate compared to the control groups (0.00 g/Kg). Furthermore, 0.60 and 1.20 g/Kg SePCH significantly enhanced amounts of white blood cells, red blood cells, platelets, lymphocytes and monocytes, and levels of hemoglobin, mean corpuscular volume and mean corpuscular hemoglobin in the hemocytes. In addition, 0.60 and 1.20 g/Kg SePCH increased the mRNA expression levels of selenocysteine lyase, selenophosphate synthase 1, 15 kDa selenoprotein, selenoprotein T2, selenoprotein H, selenoprotein P and selenoprotein K in the fish liver and intestine compared to the controls. Adequate SePCH not only significantly elevated the activities of antioxidant enzymes (Total superoxide dismutase, catalase, glutathione reductase, glutathione peroxidase), the levels of total antioxidant capacity and glutathione, while increased mRNA transcription levels of NF-E2-related factor 2, Cu/Zn-superoxide dismutase, catalase, glutathione reductase and glutathione peroxidase. However, adequate SePCH significantly decreased levels of malondialdehyde and H2O2 and the mRNA expression levels of kelch-like ECH-associated protein 1a and kelch-like ECH-associated protein 1b in the fish liver and intestine compared to the controls. Meanwhile, adequate SePCH markedly enhanced the levels of immune factors (alkaline phosphatase, acid phosphatase, lysozyme, complement component 3, complement component 4 and immunoglobulin M) and innate immune-related genes (lysozyme, hepcidin, liver-expressed antimicrobial peptide 2, complement component 3 and complement component 4) in the fish liver and intestine compared to the controls. Adequate SePCH reduced the levels of pro-inflammatory cytokines (tumour necrosis factor-α, interleukin 8, interleukin 1β and interferon γ), while increasing transforming growth factor β1 levels at both transcriptional and protein levels in the liver and intestine. The mRNA expression levels of mitogen-activated protein kinase 13 (MAPK 13), MAPK14 and nuclear factor kappa B p65 were significantly reduced in the liver and intestine of fish fed with 0.60 and 1.20 g/Kg SePCH compared to the controls. Histological sections also demonstrated that 0.60 and 1.20 g/Kg SePCH significantly increased intestinal villus height and villus width compared to the controls. Furthermore, the mRNA expression levels of tight junction proteins (zonula occludens-1, zonula occludens-3, Claudin-1, Claudin-3, Claudin-5, Claudin-11, Claudin-23 and Claudin-34) and Mucin-17 were significantly upregulated in the intestinal epithelial cells of 0.60 and 1.20 g/Kg SePCH groups compared to the controls. In conclusion, these results found that 0.60 and 1.20 g/Kg dietary SePCH can not only improve growth, hematological parameters, selenium metabolism, antioxidant capacities, enhance immune responses and intestinal functions, but also alleviate inflammatory responses. This information can serve as a useful reference for formulating feeds for largemouth bass.

Association between dietary selenium intake and the prevalence of hypertension: results from the National Health and Nutrition Examination Survey 2003-2018

Aim

The epidemiological evidence regarding the impact of dietary selenium intake on hypertension continues to be a subject of controversy. Our objective is to examine the correlation between dietary selenium intake and the prevalence of hypertension within a substantial and diverse population in the United States.

Methods

We carried out a cross-sectional study using data from the National Health and Nutrition Examination Survey (NHANES) to assess the association between dietary selenium intake and hypertension prevalence. Weight logistic regression analysis and smooth curve fitting were utilized to explore potential linear relationships. Subgroup analysis was further employed to investigate potential differences in this relationship across populations and assess potential synergies.

Results

The study included 32,928 individuals, and the average dietary selenium intake was 1.12 ± 0.53 μg. The prevalence rate of hypertension was 36.55% overall and decreased with the higher dietary selenium intake quartiles (quartiles 1, 40.25%; quartiles 2, 37.71%; quartiles 3, 36.04%, quartiles 4, 32.23%, p < 0.001). Each quartile increase in dietary selenium intake associated with 11% decreased the likelihood of prevalence of hypertension [OR = 0.89; 95% CI: 0.80-1.00; p = 0.0425]. Subgroup analyses revealed that there was no significant correlation between gender, age, body mass index, smoking status, alcohol consumption, and diabetes mellitus in relation to the association between dietary selenium intake and the prevalence of hypertension.

Conclusion

The prevalence of hypertension in adults was found to be linearly and negatively correlated with dietary selenium intake. In order to improve the prevention and treatment of hypertension, greater emphasis should be placed on selenium consumption.

Selenomethionine, a Trace Element, Increases Osteoblastic Activity of hFOB 1.19 Cells (an In Vitro Study)

Osteoporosis and resulting fractures affect a significant group of people in the world. It has been shown in many studies that selenium has positive effects on bone metabolism. Based on this information, the aim of this study is to investigate whether bone differentiation will start in a shorter time by applying selenomethionine (SeMet) to hFOB cells.First, hFOB 1.19 cells were cultured. Safe doses of SeMet were determined by MTT and LDH tests. Ossification levels were determined by alizarin red staining and measurement of alkaline phosphatase enzyme levels. The results were analyzed with statistical tests.It was observed that SeMet increased cell viability at concentrations of 10, 25, 50, 100, and 200 µM in 24 h. At these concentrations, cell viability increased above the control, the viabilities were as follows: 109.4%, 104.9%, 104.3%, 103.15%, and 100.27%. High doses of SeMet significantly reduce cell viability. According to Alizarin red staining, SeMet increases the amount of calcium deposits in hFOB cells in a dose-dependent manner. In the experimental groups, the highest ALP enzyme was determined in the 7-day SeMet application. The most effective dose was measured as 15 µM.It was determined that SeMet, which is found as a trace element in living things in nature, increases the viability of hFOB cells, which are osteoblast cell precursors, and increases osteoblastic differentiation and osteoblastic activity in these cells. Our results are at a level that sheds light on an important problem in public health.

Selenium in the treatment of mild-to-moderate Graves' orbitopathy: a 5-year prospective controlled cohort study

PURPOSE

Graves' orbitopathy (GO) is the main extrathyroidal manifestation of Graves' disease. However, limited studies have investigated the actual efficacy of selenium in GO therapy. This longitudinal study explored the effect of selenium on QOL and prognosis of patients with mild-to-moderate GO.

METHODS

We conducted a 5-year prospective controlled cohort clinical trial to determine the effect of selenium on 74 patients with mild-to-moderate GO. Patients received selenium yeast or placebo orally for 6 months and were followed up at 6 months and at 5 years by biochemical examination, ophthalmologist evaluation and QOL questionnaire to assess oculopathy and QOL.

RESULTS

(1) During a follow-up period of 3-6 months, in the selenium group, the symptoms of tearing, grittiness and conjunctival congestion improved (P < 0.01); clinical activity scores and total GO-QOL scores increased relative to baseline (P < 0.01); TRAb was decreased at the 6-month evaluation (P = 0.003); and patients treated with selenium had a higher rate of improvement and a lower rate of worsening than patients treated with placebo (P < 0.05). (2) Exploratory evaluations at 6 months after drug withdrawal confirmed the earlier results; further changes included alleviation of blurred vision and double vision symptoms in the selenium group (P < 0.01). (3) At the 5-year follow-up, compared with baseline, proptosis, clinical activity scores, TRAb level and total GO-QOL scores in both the selenium and placebo groups were significantly improved (P < 0.01).

CONCLUSION

Six months of selenium supplementation may effectively change the early course of mild-to-moderate GO, but this regimen makes no difference in long-term outcomes.

Enhancing bovine immune, antioxidant and anti-inflammatory responses with vitamins, rumen-protected amino acids, and trace minerals to prevent periparturient mastitis

Mastitis, the inflammatory condition of mammary glands, has been closely associated with immune suppression and imbalances between antioxidants and free radicals in cattle. During the periparturient period, dairy cows experience negative energy balance (NEB) due to metabolic stress, leading to elevated oxidative stress and compromised immunity. The resulting abnormal regulation of reactive oxygen species (ROS) and reactive nitrogen species (RNS), along with increased non-esterified fatty acids (NEFA) and β-hydroxybutyric acid (BHBA) are the key factors associated with suppressed immunity thereby increases susceptibility of dairy cattle to infections, including mastitis. Metabolic diseases such as ketosis and hypocalcemia indirectly contribute to mastitis vulnerability, exacerbated by compromised immune function and exposure to physical injuries. Oxidative stress, arising from disrupted balance between ROS generation and antioxidant availability during pregnancy and calving, further contributes to mastitis susceptibility. Metabolic stress, marked by excessive lipid mobilization, exacerbates immune depression and oxidative stress. These factors collectively compromise animal health, productive efficiency, and udder health during periparturient phases. Numerous studies have investigated nutrition-based strategies to counter these challenges. Specifically, amino acids, trace minerals, and vitamins have emerged as crucial contributors to udder health. This review comprehensively examines their roles in promoting udder health during the periparturient phase. Trace minerals like copper, selenium, and calcium, as well as vitamins; have demonstrated significant impacts on immune regulation and antioxidant defense. Vitamin B12 and vitamin E have shown promise in improving metabolic function and reducing oxidative stress followed by enhanced immunity. Additionally, amino acids play a pivotal role in maintaining cellular oxidative balance through their involvement in vital biosynthesis pathways. In conclusion, addressing periparturient mastitis requires a holistic understanding of the interplay between metabolic stress, immune regulation, and oxidative balance. The supplementation of essential amino acids, trace minerals, and vitamins emerges as a promising avenue to enhance udder health and overall productivity during this critical phase. This comprehensive review underscores the potential of nutritional interventions in mitigating periparturient bovine mastitis and lays the foundation for future research in this domain.

How Can Selected Dietary Ingredients Influence the Development and Progression of Endometriosis?

Endometriosis is a chronic, hormone-dependent disease characterized by the presence of endometrial tissue in ectopic locations. Since the treatment options for this disease are still limited, and the cure rate is unsatisfactory, the search for ways to treat symptoms and modify the course of the disease is of key importance in improving the quality of life of patients with endometriosis. So far, the literature has shown that nutrition can influence endometriosis through hormonal modification and altering the inflammatory or oxidative response. Since the importance of nutrition in this disease is still a subject of scientific research, we aimed to summarize the current knowledge on the role of dietary modifications in endometriosis. Our review showed that nutrients with anti-inflammatory and antioxidant properties, including most vitamins and several trace elements, may influence the pathogenesis of endometriosis and can be considered as the nutrients preventing the development of endometriosis. However, despite the many discoveries described in this review, further interdisciplinary research on this topic seems to be extremely important, as in the future, it may result in the development of personalized therapies supporting the treatment of endometriosis.

Selenium supplementation and placebo are equally effective in improving quality of life in patients with hypothyroidism

PURPOSE

We investigated whether selenium supplementation improves quality-of-life (QoL) in patients with autoimmune thyroiditis (ID:NCT02013479).

METHODS

We included 412 patients ≥18 years with serum thyroid peroxidase antibody (TPOAb) level ≥100 IU/mL in a multicentre double-blinded randomised clinical trial. The patients were allocated 1:1 to daily supplementation with either 200 μg selenium as selenium-enriched yeast or matching placebo tablets for 12 months, as add-on to levothyroxine (LT4) treatment. QoL, assessed by the Thyroid-related Patient-Reported-Outcome questionnaire (ThyPRO-39), was measured at baseline, after six weeks, three, six, 12, and 18 months.

RESULTS

In total, 332 patients (81%) completed the intervention period, of whom 82% were women. Although QoL improved during the trial, no difference in any of the ThyPRO-39 scales was found between the selenium group and the placebo group after 12 months of intervention. In addition, employing linear mixed model regression no difference between the two groups was observed in the ThyPRO-39 composite score (28.8 [95%CI:24.5-33.6] and 28.0 [24.5-33.1], respectively; P=0.602). Stratifying the patients according to duration of the disease at inclusion, ThyPRO-39 composite score, TPOAb level, or selenium status at baseline did not significantly change the results. TPOAb levels after 12 months of intervention were lower in the selenium group than in the placebo group (1995 [95%CI:1512-2512] vs. 2344 kIU/L [1862-2951]; P=0.016) but did not influence LT4 dosage or free triiodothyronine/free thyroxin ratio.

CONCLUSION

In hypothyroid patients on LT4 therapy due to autoimmune thyroiditis, daily supplementation with 200 μg selenium or placebo for 12 months improved QoL to the same extent.

SeMet alleviates AFB1-induced oxidative stress and apoptosis in rabbit kidney by regulating Nrf2//Keap1/NQO1 and PI3K/AKT signaling pathways

The purpose of this study was to explore the protective effect of SeMet on renal injury induced by AFB1 in rabbits and its molecular mechanism. Forty rabbits of 35 days old were randomly divided into control group, AFB1 group (0.3 mg AFB1/kg b.w), 0.2 mg/kg Se + AFB1 group (0.3 mg AFB1/kg b.w + 0.2 mg SeMet/kg feed) and 0.4 mg/kg Se + AFB1 group (0.3 mg AFB1/kg b.w + 0.4 mg SeMet/kg feed). The SeMet treatment group was fed different doses of SeMet diets every day for 21 days. On the 17-21 day, the AFB1 treatment group, the 0.2 mg/kg Se + AFB1 group and the 0.4 mg/kg Se + AFB1 group were administered 0.3 mg AFB1 /kg b.w by gavage (dissolved in 0.5 ml olive oil) respectively. The results showed that AFB1 poisoning resulted in the changes of renal structure, the increase of renal coefficient and serum biochemical indexes, the ascent of ROS and MDA levels, the descent of antioxidant enzyme activity, and the significant down-regulation of Nrf2, HO-1 and NQO1. Besides, AFB1 poisoning increased the number of renal apoptotic cells, rised the levels of PTEN, Bax, Caspase-3 and Caspase-9, and decreased the levels of PI3K, AKT, p-AKT and Bcl-2. In summary, SeMet was added to alleviate the oxidative stress injury and apoptosis of kidney induced by AFB1, and the effect of 0.2 mg/kg Se + AFB1 is better than 0.4 mg/kg Se + AFB1.

Multifunctional nanoparticle-mediated combining therapy for human diseases

Combining existing drug therapy is essential in developing new therapeutic agents in disease prevention and treatment. In preclinical investigations, combined effect of certain known drugs has been well established in treating extensive human diseases. Attributed to synergistic effects by targeting various disease pathways and advantages, such as reduced administration dose, decreased toxicity, and alleviated drug resistance, combinatorial treatment is now being pursued by delivering therapeutic agents to combat major clinical illnesses, such as cancer, atherosclerosis, pulmonary hypertension, myocarditis, rheumatoid arthritis, inflammatory bowel disease, metabolic disorders and neurodegenerative diseases. Combinatorial therapy involves combining or co-delivering two or more drugs for treating a specific disease. Nanoparticle (NP)-mediated drug delivery systems, i.e., liposomal NPs, polymeric NPs and nanocrystals, are of great interest in combinatorial therapy for a wide range of disorders due to targeted drug delivery, extended drug release, and higher drug stability to avoid rapid clearance at infected areas. This review summarizes various targets of diseases, preclinical or clinically approved drug combinations and the development of multifunctional NPs for combining therapy and emphasizes combinatorial therapeutic strategies based on drug delivery for treating severe clinical diseases. Ultimately, we discuss the challenging of developing NP-codelivery and translation and provide potential approaches to address the limitations. This review offers a comprehensive overview for recent cutting-edge and challenging in developing NP-mediated combination therapy for human diseases.

Developmental toxicity and neurobehavioral effects of sodium selenite and selenium nanoparticles on zebrafish embryos

Selenium, a trace mineral, is essential for several physiological processes in humans and animals. It is an antioxidant vital for the immunological response, DNA synthesis, thyroid hormone metabolism, and antioxidant defense enzymes. Zebrafish embryos and larvae were exposed to different concentrations of sodium selenite (SodSe) and selenium nanoparticles (SeNs) at various developmental stages. The study evaluated the impact of SodSe and SeNs on larvae survival, hatching rate, and morphological abnormalities. Also, acridine orange staining was used to analyze the apoptotic cell death, and behavioral tests were conducted to assess anxiety-like behaviors. The results showed that both SodSe and SeNs influence the development and neurobehavior of zebrafish larvae in a concentration-dependent manner. SodSe at high concentration causes low survival rates, delayed hatching, and increased morphological defects in zebrafish larvae. In addition, exposure to SodSe resulted in elevated apoptosis in different larval tissues. Zebrafish larvae treated with SodSe and SeNs exhibited anxiety-like behaviour, increased thigmotaxis, less exploratory behaviour, and less swimming patterns. The nerve conductions and stimuli responses evaluated through acetylcholine esterase (AChE) and cortisol assays, revealed a decrease in the activity in a dose-dependent manner of SodSe and SeNs. Interestingly, the effects of SeNs were lower even at higher concentrations when compared with SodSe at lower concentrations on zebrafish embryos. This shows that SeNs synthesized through biological methods may be less toxic and may have lower effect on the development and neurobehavior of zebrafish larvae. Thus, our study confirms the cytotoxic and neurobehavioral effects of SodSe and suggests the use of SeNs at lower concentration to provide insights into better understanding of developmental stages and metabolic pathways in zebrafish larvae.

Selenium Deficiency Can Promote the Expression of VEGF and Inflammatory Factors in Cartilage Differentiation and Mediates Cartilage Injury

Selenium plays a crucial role as a micronutrient, primarily exerting its biological functions through selenoproteins. It has been established that selenium deficiency adversely impacts cartilage development, leading to alterations in chondrocyte function. In regions with low selenium intake, endemic osteochondrosis has been documented, characterized by compromised growth plate and articular cartilage formation. Vascular endothelial growth factor (VEGF) stands out as a pivotal angiogenic factor, with elevated levels contributing significantly to vascular invasion into chondrocytes. This VEGF-mediated invasion serves as a key signal, prompting morphological changes in the growth plate and initiating cartilage remodeling. In animal models, the selenium deficiency group exhibited heightened levels of the cartilage damage marker matrix metalloproteinases 13 (MMP13). This resulted in articular cartilage degeneration, accompanied by a substantial increase in VEGF expression within the growth plate and articular cartilage, as compared to the normal group. In a chondrogenic progenitor cell (CPC) differentiation model, insufficient selenium induced chondrocyte damage and upregulated inflammatory factors such as inducible NO synthase (iNOS) and cyclooxygenase-2 (COX2). The selenium-deficient groups showed elevated expressions of VEGF, VEGFR2, MMP13, Collagen X, and Angiopoietin 1, accelerating the degradation of the extracellular matrix (ECM), which further promoted the development of cartilage-related diseases. Taken together, these findings provide novel insights for a better understanding of the role of low selenium in cartilage degeneration and angiogenesis. They shed light on the intricate influence of low selenium levels on the development of articular cartilage, emphasizing the interconnected pathways and processes involved.

Shining a Light on Selenium: a Meta-analysis of Supplementation in Multiple Sclerosis

Multiple sclerosis (MS) is a chronic immune-mediated demyelinating disease of the central nervous system. Selenium is a trace element with significant antioxidant activity. This study aimed to seek evidence concerning selenium supplementation in MS. A systematic search was performed on PubMed, Web of Science, Scopus, and Embase databases to identify the studies assessing the consumption rate, efficacy, and safety of selenium and selenium-containing supplementations in MS patients. The meta-analysis was performed using the Comprehensive Meta-Analysis and the risk of bias was evaluated using the Joanna Briggs Institute's critical appraisal tools. A total of 9 studies were included, which consisted of six studies regarding the rate of selenium supplement consumption in MS patients, with a total sample size of 2381 patients. Based on the quantitative synthesis, 14.3% (95% CI, 12.8-16.0%; I2, 3.58%) of MS patients had current selenium supplements usage, and 11.3% (95% CI, 7.6-16.6%; I2, 81.40%) of patients had used selenium supplements previously. Although there is no evidence regarding supplementation with selenium alone, three RCT studies reported the safety of selenium-containing supplementation use in MS with improved inflammation and oxidative stress conditions. The findings of this study show that over 10% of patients with MS used selenium supplements, with no clinical significance supporting the benefits. There is a lack of evidence regarding the safety and efficacy of selenium supplements in MS patients. Due to the limited number of included studies and the lack of comprehensive and specific studies regarding selenium supplements in MS, the results must be interpreted with caution, and future clinical trials are required.

Selenium-More than Just a Fortuitous Sulfur Substitute in Redox Biology

Living organisms use selenium mainly in the form of selenocysteine in the active site of oxidoreductases. Here, selenium's unique chemistry is believed to modulate the reaction mechanism and enhance the catalytic efficiency of specific enzymes in ways not achievable with a sulfur-containing cysteine. However, despite the fact that selenium/sulfur have different physicochemical properties, several selenoproteins have fully functional cysteine-containing homologues and some organisms do not use selenocysteine at all. In this review, selected selenocysteine-containing proteins will be discussed to showcase both situations: (i) selenium as an obligatory element for the protein's physiological function, and (ii) selenium presenting no clear advantage over sulfur (functional proteins with either selenium or sulfur). Selenium's physiological roles in antioxidant defence (to maintain cellular redox status/hinder oxidative stress), hormone metabolism, DNA synthesis, and repair (maintain genetic stability) will be also highlighted, as well as selenium's role in human health. Formate dehydrogenases, hydrogenases, glutathione peroxidases, thioredoxin reductases, and iodothyronine deiodinases will be herein featured.

Nutritional Strategies to Mitigate Post-Weaning Challenges in Pigs: A Focus on Glucans, Vitamin D, and Selenium

This review examines the challenges faced by the pig industry, with a specific focus on improving the health and growth of weaned pigs. It emphasizes the immediate necessity of investigating alternative approaches to managing pig nutrition and health due to restrictions on the use of antibiotics and the prohibition of zinc oxide in weaned pig diets. The weaning phase is identified as a critical stage in piglet development, characterized by stressors that affect their gastrointestinal health, immune responses, and overall physiology. The primary challenge during weaning arises from transitioning piglets from a digestible milk-based diet to a less digestible cereal-based feed, causing nutritional stress. This manifests as reduced feed intake, leading to gastrointestinal disturbances, intestinal inflammation, and adverse effects on intestinal structure and microbiota. To address these challenges and optimize piglet development, various nutritional strategies have been explored. Notably, glucans, particularly β-glucans from fungi, cereals, algae, and yeast, show promise in alleviating weaning-related issues. Furthermore, it is important to highlight the critical roles played by Vitamin D and selenium in piglet nutrition. These essential nutrients can be sourced naturally from enriched mushrooms that are specifically enriched with Vitamin D and selenium, providing a sustainable dietary option. In conclusion, effective nutritional strategies, including glucans, Vitamin D, selenium, and enriched mushrooms, are beneficial for addressing weaning-related challenges.

Moderate selenium mitigates hand grip strength impairment associated with elevated blood cadmium and lead levels in middle-aged and elderly individuals: insights from NHANES 2011-2014

Background: Selenium (Se) has been reported to have an antagonistic effect on heavy metals in animals. Nevertheless, there is a lack of epidemiological research examining whether Se can mitigate the adverse effects of cadmium (Cd) and lead (Pb) on hand grip strength (HGS) in middle-aged and elderly individuals. Methods: This study used data from the 2011-2014 National Health and Nutrition Examination Survey (NHANES). HGS measurements were conducted by trained examiners with a dynamometer. Concentrations of Se, Cd, and Pb in blood were determined via inductively coupled plasma mass spectrometry. We employed linear regression, restricted cubic splines, and quantile g-computation (qgcomp) to assess individual and combined associations between heavy metals and HGS. The study also explored the potential influence of Se on these associations. Results: In both individual metal and multi-metal models adjusted for confounders, general linear regression showed Se's positive association with HGS, while Cd and Pb inversely related to it. At varying Se-Cd and Se-Pb concentrations, high Se relative to low Se can attenuate Cd and Pb's HGS impact. An inverted U-shaped correlation exists between Se and both maximum and combined HGS, with Se's benefit plateauing beyond approximately 200 μg/L. Stratified analysis by Se quartiles reveals Cd and Pb's adverse HGS effects diminishing as Se levels increase. Qgcomp regression analysis detected Se alleviating HGS damage from combined Cd and Pb exposure. Subsequent subgroup analyses identified the sensitivity of women, the elderly, and those at risk of diabetes to HGS impairment caused by heavy metals, with moderate Se supplementation beneficial in mitigating this effect. In the population at risk for diabetes, the protective role of Se against heavy metal toxicity-induced HGS reduction is inhibited, suggesting that diabetic individuals should particularly avoid heavy metal-induced handgrip impairment. Conclusion: Blood Cd and Pb levels are negatively correlated with HGS. Se can mitigate this negative impact, but its effectiveness plateaus beyond 200 μg/L. Women, the elderly, and those at risk of diabetes are more vulnerable to HGS damage from heavy metals. While Se supplementation can help, its protective effect is limited in high diabetes risk groups.

Interorgan communication with the liver: novel mechanisms and therapeutic targets

The liver is a multifunctional organ that plays crucial roles in numerous physiological processes, such as production of bile and proteins for blood plasma, regulation of blood levels of amino acids, processing of hemoglobin, clearance of metabolic waste, maintenance of glucose, etc. Therefore, the liver is essential for the homeostasis of organisms. With the development of research on the liver, there is growing concern about its effect on immune cells of innate and adaptive immunity. For example, the liver regulates the proliferation, differentiation, and effector functions of immune cells through various secreted proteins (also known as "hepatokines"). As a result, the liver is identified as an important regulator of the immune system. Furthermore, many diseases resulting from immune disorders are thought to be related to the dysfunction of the liver, including systemic lupus erythematosus, multiple sclerosis, and heart failure. Thus, the liver plays a role in remote immune regulation and is intricately linked with systemic immunity. This review provides a comprehensive overview of the liver remote regulation of the body's innate and adaptive immunity regarding to main areas: immune-related molecules secreted by the liver and the liver-resident cells. Additionally, we assessed the influence of the liver on various facets of systemic immune-related diseases, offering insights into the clinical application of target therapies for liver immune regulation, as well as future developmental trends.

Moderate selenium alleviates the pulmonary function impairment induced by cadmium and lead in adults: A population-based study

Selenium (Se) has been reported to have an antagonistic effect on heavy metals in animals. However, there is no epidemiological study investigating whether Se could protect against the pulmonary toxicity of Cadmium (Cd) and Lead (Pb). Data was collected from the 2011-2012 National Health and Nutrition Examination Survey (NHANES) cycle. Pulmonary function was assessed by Forced Vital Capacity (FVC), Forced Expiratory Volume 1st Second (FEV1) and FEV1/FVC. Blood concentrations of Cd, Pb, and Se were measured using inductively coupled plasma mass spectrometry. Linear regression, restricted cubic splines, and quantile-based g-computation (qgcomp) were performed to evaluate the individual and joint associations of Cd and Pb with pulmonary function and whether Se modified these associations. In the adjusted multi-metal model, every 1-unit increase in Cd, FEV1, FVC, and FEV1/FVC decreased by 76.437 mL (95 % CI: -110.928 to -41.947), 42.719 mL (95 % CI: -84.553 to -0.885), and 0.012 (95 % CI: -0.016 to -0.007), respectively. Meanwhile, FEV1 decreased by 9.37 mL (95 % CI: -18.61 to -0.13) for every 1 unit increase in Pb. Furthermore, we found an inverted U-shape association between Se and lung function, and participants in the second quartile Se group had the highest increases in FEV1 and FVC compared with participants in the lowest quartile. Qgcomp model also revealed that the toxic metal mixture (Cd and Pb) exhibited a significant inverse association with FEV1 and FEV1/FVC. Furthermore, we found that the inverse association of Pb and Cd, either alone or in combination, with pulmonary function first diminished with increasing Se levels but was re-enforced when blood Se concentrations were in the highest quartile. Our results indicated that moderate Se attenuated the harmful effects of Cd and Pb on lung function.

Comparative Analysis of Gut Microbiota from Rats Induced by Se Deficiency and T-2 Toxin

The aim of this study was to analyze the differences in gut microbiota between selenium deficiency and T-2 toxin intervention rats. Knee joint and fecal samples of rats were collected. The pathological characteristics of knee cartilage were observed by safranin O/fast green staining. DNA was extracted from fecal samples for PCR amplification, and 16S rDNA sequencing was performed to compare the gut microbiota of rats. At the phylum level, Firmicutes (81.39% vs. 77.06%) and Bacteroidetes (11.11% vs. 14.85%) were dominant in the Se-deficient (SD) group and T-2 exposure (T-2) groups. At the genus level, the relative abundance of Ruminococcus_1 (12.62%) and Ruminococcaceae_UCG-005 (10.31%) in the SD group were higher. In the T-2 group, the relative abundance of Lactobacillus (11.71%) and Ruminococcaceae_UCG-005 (9.26%) were higher. At the species level, the high-quality bacteria in the SD group was Ruminococcus_1_unclassified, and Ruminococcaceae_UCG-005_unclassified in the T-2 group. Lactobacillus_sp__L_YJ and Lactobacillus_crispatus were the most significant biomarkers in the T-2 group. This study analyzed the different compositions of gut microbiota in rats induced by selenium deficiency and T-2 toxin, and revealed the changes in gut microbiota, so as to provide a certain basis for promoting the study of the pathogenesis of Kashin-Beck disease (KBD).

Maternal suboptimal selenium intake and low-level lead exposure affect offspring's microglial immune profile and its reactivity to a subsequent inflammatory hit

Micronutrients such as selenium (Se) are essentials since prenatal life to support brain and cognitive development. Se deficiency, which affects up to 1 billion people worldwide, can interact with common adverse environmental challenges including (Pb), exacerbating their toxic effects. Exploiting our recently validated rat model of maternal Se restriction and developmental low Pb exposure, our aims were to investigate: (i) the early consequences of suboptimal Se intake and low-Pb exposure on neuroinflammation in neonates' whole brains; (ii) the potential priming effect of suboptimal Se and low-Pb exposure on offspring's glial reactivity to a further inflammatory hit. To these aims female rats were fed with suboptimal (0.04 mg/kg; Subopt) and optimal (0.15 mg/kg; Opt) Se dietary levels throughout pregnancy and lactation and exposed or not to environmentally relevant Pb dose in drinking water (12.5 µg/mL) since 4 weeks pre-mating. We found an overall higher basal expression of inflammatory markers in neonatal brains, as well as in purified microglia and organotypic hippocampal slice cultures, from the Subopt Se offspring. Subopt/Pb cultures were highly activated than Subopt cultures and showed a higher susceptibility to the inflammatory challenge lipopolysaccharide than cultures from the Opt groups. We demonstrate that even a mild Se deficiency and low-Pb exposure during brain development can influence the neuroinflammatory tone of microglia, exacerbate the toxic effects of Pb and prime microglial reactivity to subsequent inflammatory stimuli. These neuroinflammatory changes may be responsible, at least in part, for adverse neurodevelopmental outcomes.

Selenium dietary intake and survival among CRC patients

Background: Despite advances in prevention and treatment, colorectal cancer remains the second most common cause of cancer death. To date, little is known about the role of prediagnostic selenium intake in colorectal cancer survival. Objective: The purpose of the study was to verify whether selenium intake in habitual diet before diagnosis is associated with survival in colorectal cancer patients. Study design: This was a prospective observation of patients primarily recruited for a case-control study between 2000 and 2012 in Cracow, Poland. A group of 671 incident cases of colorectal cancer was included. Habitual diet was assessed using a validated 148-item food questionnaire. 338 deaths were identified throughout 2017 by the Polish National Vital Registry. To evaluate the impact of dietary selenium on survival, the multivariable Cox regression model was used. Results: After standardization for several potential confounders (including key determinants, such as radical surgery, chemotherapy, tumor stage, and dietary factors), a decrease in the risk of death from colorectal cancer was observed in the group with higher dietary selenium intake (≥48.8 μg/day, group mean: 63.9 μg/day) compared to the group with lower dietary selenium intake (<48.8 μg/day, mean: 38.5 μg/day) (HR=0.73; 95% CI: 0.54-0.98) (the median was used for categorization). Conclusion: Our study suggests selenium as an additional dietary factor which may be associated with survival among colorectal cancer patients referred to surgery. Due to the observational nature of the study, the results should be taken with caution. These preliminary findings, however, provide the basis for well-structured clinical trials.

Serum Selenium and Inflammation in Individuals with Human Immunodeficiency Virus Infection

HIV infection has been linked to selenium deficiency and chronic inflammation. Both selenium deficiency and inflammation have been associated with poor health outcomes among individuals with HIV. However, the role of serum selenium levels in inflammation has not been studied among individuals with HIV. We assessed the relationship of serum selenium levels to C-reactive protein (CRP), a marker of inflammation, in individuals with HIV in Kathmandu, Nepal. In this cross-sectional study, we measured the normal serum CRP and selenium levels of 233 individuals with HIV (109 women and 124 men) using the latex agglutination turbidimetric and atomic absorption methods, respectively. We used multiple linear regression analysis in examining the association of serum selenium levels with CRP adjusting for sociodemographic and clinical parameters, including antiretroviral therapy, CD4+ T cell count, chronic diseases, and body mass index. The geometric means of CRP and selenium levels were 1.43 mg/liter and 9.65 μg/dL, respectively. Overall, serum selenium levels were inversely associated with CRP levels (β for one unit change in log selenium; β = -1.01, p = .06). Mean CRP levels significantly decreased with increasing selenium across selenium tertiles (p for trend = .019). The mean serum CRP levels were 40.8% lower in the highest selenium tertile than in the lowest. Our study suggests that high serum selenium levels may reduce serum CRP levels in individuals with HIV, although a longitudinal study is warranted to establish causality.

Selenium reduces hepatopancreas lipid accumulation of grass carp (Ctenopharyngodon idella) fed high-fat diet via lipophagy activation

It has been reported that selenium (Se) can reduce hepatopancreas lipid accumulation induced by high-fat diet. However, its mechanism is still unknown. This study aims to investigate the specific mechanisms by which Se alleviates high-fat diet-induced lipid accumulation. Grass carp were fed control diet (4.8% lipid, Con), high-fat diet (8.8% lipid, HFD) or HFD supplemented with 0.3 mg/kg nano-Se (HSe0.3) for 10 weeks. Growth performance, Se deposition, lipid accumulation, hepatic ultrastructure, and gene and protein expression levels associated with autophagy were examined. Furthermore, oleic acid (OA) was used to incubate the grass carp hepatocytes (L8824) for 24 h, and then the L8824 were incubated with sodium selenite in presence or absence of an autophagy inhibitor for 24 h. L8824 was analyzed for triglyceride concentration, immunofluorescence, and gene and protein expression levels associated with autophagy. We found that dietary nano-Se improved the growth of fish fed HFD and also decreased hepatosomatic index and intraperitoneal fat ratio of fish fed HFD (P < 0.05). HFD significantly increased hepatopancreas lipid accumulation and decreased autophagic activity (P < 0.05). Treatment of grass carp fed HFD with nano-Se decreased lipid accumulation and restored hepatic autophagy (P < 0.05). In vitro, Se (100 μM sodium selenite) obviously activated autophagy in L8824 incubated with OA, and consequently reduced the lipid accumulation induced by OA (P < 0.05). Furthermore, using pharmacological inhibition (chloroquine) of the autophagy greatly diminished the beneficial effects of Se on alleviating OA-induced lipid accumulation and increased the co-localization of lipid droplets with autophagosome (P < 0.05), which indicated that Se increased autophagic flux. In conclusion, these results suggest that Se alleviates HFD-induced hepatopancreas lipid accumulation by activating lipophagy.

Maternal Selenium-Enriched Yeast Supplementation in Sows Enhances Offspring Growth and Antioxidant Status through the Nrf2/Keap1 Pathway

This study evaluated the effects of maternal selenium-enriched yeast (SeY) supplementation during late gestation and lactation on sow performance, transfer of selenium (Se) and redox status, and gut microbiota community, as well as on the gut health of offspring. Seventy pregnant sows on day 85 of gestation were randomly allocated to the following two treatments: (1) sows who were fed a basal diet (basal diet contained 0.3 mg/kg Se as Na2SeO3, n = 35); (2) and sows who were fed a SeY-supplemented diet (basal diet with 0.2 mg/kg Se as SeY, n = 35). The offspring piglets were only cross-fostered within the group on day 3 of lactation (L3) according to the pig farm epidemic prevention policy. The plasma, milk, and feces samples from 10 sows, as well as plasma and intestinal samples per treatment, were collected on L1 and L21, respectively. Our results showed that maternal SeY supplementation increased the first week average weight and ADG of piglets (p < 0.05). Compared with the CON group, the SeY supplementation increased the Se content in the plasma and milk of sows and the plasma of piglets on L1 and L21 (p < 0.05). In addition, in sows, the levels of fat in the milk on L21, the level of IgA, T-AOC, and GSH-Px in the plasma on L21, and the level of T-AOC and GSH-Px in the colostrum were increased, while the MDA content was decreased in the plasma on L1 and in the colostrum and milk on L14 (p < 0.05). In the piglet plasma, the levels of IgA on L1 and L21, GSH-Px on L1, and GSH on L21 were increased, while the MDA content was decreased on L1 (p < 0.05). Maternal SeY supplementation up-regulated the small intestinal protein abundances of MUC1, E-cadherin, ZO-1, occludin, and claudin and activated the Nrf2/Keap1 signaling pathway in weaned offspring piglets. The 16S rRNA sequencing results showed that fecal microbiota had distinct separations during lactation, and the relative abundances of unclassified_f_Lachnospiraceae, Prevotaceae_UCG-001, and Lachnospiraceae_NK4A136_group were increased on L1. Collectively, the current findings suggest that maternal SeY supplementation during late gestation and lactation could improve the piglet's growth performance, Se status, antioxidant capacity and immunoglobulins transfer at the first week of lactation, as well as alter the fecal microbiota composition by increasing antioxidative-related and SCFA-producing microbiota in sows. These changes contributed to enhancing the small intestinal barrier function and activating the Nrf2/Keap1 pathway in offspring.