Supranutritional Se Research Articles

Impact of Dietary Supranutritional Selenium on Improving the Meat Quality of Goats

Selenium (Se) a crucial micronutrient, is required in many biochemical processes in animals. Supranutritional levels of Se in the diet have been suggested to potentially enhance meat quality in livestock. However, limited research exists on the impact of dietary supranutritional Se on meat quality in goats. Objective: To evaluate the influence of dietary supranutritional Se on goat muscle meat quality, examining pH, water holding capacity (WHC), cooking and drip losses, moisture, protein, fat, ash, and glycogen contents. Methods: Sixteen male goats were randomly grouped into two viz., A and B (n = 8 per group) and offered basal diets without (group A) or with addition of Se (group B) for 10 weeks. Meat samples were collected from the longissimus dorsi (LD) and semimembranosus (SM) muscles at the completion of trial and the physico-chemical characteristics were determined. Results: Supranutritional Se supplementation resulted in significantly higher (P < 0.05) WHC and lower (P < 0.05) cooking and drip losses in both LD and SM muscles compared with control. Additionally, the protein and fat contents were significantly elevated (P < 0.05) and the ash contents lowered (P < 0.05) in both LD and SM muscles of goats fed Se supplemented diet compared with control. However, the pH and glycogen contents were not altered (P > 0.05) between the two groups. Conclusions: The findings of present trial demonstrated that supranutritional Se supplementation improved the quality of goat meat, contributing to its nutritional value and consumer acceptance.

59 Supranutritional Selenium Supplementation During Different Trimesters of Pregnancy in Beef Cows Affects Gene Expression of Monocyte Cells

Abstract Selenium (Se) is an essential micronutrient with beneficial effects on performance and immune function. Selenium plays a key role in enzymatic and metabolic pathways, primarily through selenocysteine-containing proteins. Despite increasing knowledge on the role of Se on conceptus development, less is known about its effects on maternal immune responses during gestation. Thus, our goal was to investigate the effects of supranutritional Se-supplementation during different trimesters of pregnancy on gene expression of monocyte blood cells and the underlying biological pathways. To this end, crossbred Angus cows (n = 40) received, except for the control group (CTR), Se-yeast boluses (105 mg of Se/wk) during the first (TR1), second (TR2), or third (TR3) trimester of gestation. Before calving, blood samples were collected from a jugular vein, and the monocytes were isolated and used for total RNA extraction. After quality control of the RNA-Seq data, 13,810 genes were tested for differential expression analysis using a t-test method implemented in the CeTF R-package. We identified 3,904 unique differentially expressed genes (DEGs) across all group comparisons (FDR < 0.05). Differentially expressed selenoprotein-coding genes included SELENOI, SELENOM, SELENON, SELENOP, SELENOT, and SEPSECS. Most of these genes were downregulated in the Se-supplemented groups compared with CTR. However, SELONOP was upregulated in TR1 and TR2 groups, and SELENOM in TR3 compared with CTR. Biological processes over-represented by the DEGs, were retrieved using the WebGestalt software (FDR < 0.05). Immune-related biological processes included positive regulation of the immune system process, immune system development, leukocyte migration, and inflammatory response. Genes underlying these biological processes included ILDR1, IL21R, IL9R, and IL18BP, all of which were upregulated in TR2 compared with CTR. On the other hand, IL1R1, IL6R, and IL1RN genes were downregulated in the Se-supplemented groups. Our results provide evidence that genes underlying immune cell function and Se metabolism were affected by supranutritional Se supplementation.

Effect of Supranutritional Dosage Selenium in Neonatal Goat Kids on Productive Performance, Physicochemical Profiles in Meat, Selenium Levels in Tissues, and Histopathological Findings.

Selenium (Se) is an essential element and antioxidant that catalyzes the destruction of hydrogen peroxide formed during cellular oxidative metabolism. Doses of Se as selenomethionine (SeMe) by oral route are 0.1-0.3 mgSe/kg DM, while the dose by parenteral route with sodium selenite (Na2SeO3) is 0.1 mgSe/BW. The effects of supranutritional Se supplementation on normal kids have rarely been studied. The objective of the study was to evaluate both Se sources on growth performance, Se in tissues, histopathological findings, and meat characteristics.Forty-five kids of the Pastoreña breed with 25-day age were distributed (4.7 ± 1.13kg) in three treatments: a) control group, C: consumption with goat milk (GM: containing 0.135mgSe/g); b) NaSe: GM plus Na2SeO3 injectable, 0.25 mgSe/kg BW; c) SeMe: GM plus oral dosage, 0.3mgSe as SeMe daily. Fifteen animals per treatment were slaughtered at 7, 14, and 21days.Feed conversion improved (P < 0.05) with Se supplement (P < 0.05) at 7 and 14days. SeMe had higher protein and fat meat content (P < 0.05). SeMe increased Se liver at 14 and 21days. NaSe and SeMe had higher (P < 0.05) levels of Se kidney. SeMe-21d showed 42% mononuclear and periportal cell infiltration lesions. In conclusion, Se administered through milk in goat kids was insufficient to prevent nutritional muscular dystrophy. The supranutritional dose of 0.25mg/kg as NaSe was sufficient to maintain the Se level in tissues. SeMe increased Se liver and kidney efficiently. Both Se sources improved the bioavailability of the mineral in kids.

PSII-A-6 Evaluation of Maternal Plane of Nutrition and Selenium Supplementation on the Neonatal Fragment Crystallizable Receptor (Fcrn) in ewe Mammary Tissue

Abstract Maternal immunoglobulin G (IgG) in livestock species is transferred to the offspring exclusively through colostrum. In ruminants, a highly selective mammary barrier allows only immunoglobulin G1 to enter colostrum in substantial amounts. The neonatal fragment crystallizable receptor (FcRn) is responsible for the bidirectional transport of IgG; however, its role in concentrating IgG into colostrum is not well described. The objective of this study was to evaluate maternal nutrition and supranutritional selenium (Se) supplementation on FcRn abundance in mammary tissue. Pregnant Rambouillet ewes (n = 80) were used in a 2 x 3 factorial treatment arrangement which included the main effects of dietary Se [adequate Se (9.5 µg/kg of BW) vs. high Se (81.8 µg/kg of BW)] and plane of nutrition [60%, 100%, and 140% of requirements]. After parturition, ewe mammary glands were collected, and tissue samples were fixed in 10% NBF before paraffin embedding and sectioning. Cross-sections (5 μm) were mounted onto glass slides, deparaffinized, stained for FcRn, and counterstained with DAPI. Areas of tissue cross-sections were captured with Plan-Apochromat 20x/0.8 NA lens using the tiling module of Zeiss software. Images were analyzed using ImagePro Premiere software. Relative fluorescence within the areas of interest was used as an indicator of FcRn abundance with data presented as receptor abundance per glandular tissue area. Data were analyzed using the general linear model procedure of SAS. High Se supplementation increased FcRn abundance per glandular area (P = 0.01). Abundance of mammary FcRn was not influenced by maternal plane of nutrition. Mammary FcRn was positively correlated (r2 = 0.25; P = 0.02) with IgG concentration in colostrum. Results indicate the presence of FcRn in ewe mammary tissue and correlation with colostral IgG. Further evaluation of the role of supranutritional Se and the FcRn is needed.

Ameliorative effects of supranutritional selenium on TLR-4-NF-kB-TNF-α-mediated hepatic oxidative injury and inflammation in goats fed high concentrate diet.

We examined whether surplus dietary selenium (Se) supply could alleviate high concentrate (HC) diet-induced hepatic oxidative stress (OS) and inflammation. Eighteen young goats were distributed into three groups; were fed low (LC, concentrate: forage; 35: 65), high concentrate (HC, 65: 35), or Se-supplemented HC (HCSe, 65: 35 +0.5mg Se kg-1 diet) diets for 10 weeks. Short chain fatty acids, OS markers and immunoinflammatory genes expressions were assessed through gas chromatograph, kits, and RT-qPCR, respectively. Compared with LC, HC diet increased (p< .05) colonic and serum lipopolysaccharide (LPS) levels and induced hepatic oxidative injury by increasing (p< .05) malondialdehyde (MDA) levels and decreasing (p< .05) activities of glutathione peroxidase, superoxide dismutase, and catalase. HC diet altered hepatic mRNA expressions of toll-like receptor-4 (TLR-4), cluster of differentiation-14 (CD-14), tumor necrosis factor-α (TNF-α), TNF receptor-associated factor-6 (TRAF-6), nuclear factor kappa B (NF-κB), interleukin-1β (IL-1β), IL-10, IL-13, LPS-binding protein (LBP), serum amyloid A (SAA), α-acid glycoprotein (AGP), and albumin (ALB). Conversely, extra-Se supply lowered LPS and attenuated antioxidant status and inflammation in liver. In conclusion, HC diet induced oxidative lesions and TLR-4 pathway-mediated inflammation, whereas supranutritional Se alleviated oxidative and inflammatory lesions through TLR-4 pathway regulation in goat liver.

Nutraceutical role of supra-nutritional selenium in healthy buffalo (Bubalus bubalis) calves

Male buffalo (Bubalus bubalis) calves (n = 10) were divided equally into control (fed basal diet had 0.23 ppm Se) and treatment (fed additional supra-nutritional Se at 0.3 mg/kg dry matter intake) groups to evaluate the nutraceutical role of selenium. Nutraceutical level of Se enhanced (P < 0.01) the percentage of monocyte cells in blood as well as Se level of plasma, without influencing most of the studied hemotological parameters including macro and micro minerals. Among oxidative stress markers, lipid peroxidation level was low (P < 0.05) in the treatment group at the end of the feeding trial with a high (P < 0.05) overall average of the antioxidative enzyme glutathione peroxidase. Parameters like reduced glutathione, catalase, superoxide dismutase, ceruloplasmin, vitamins A, E, and β-carotene remained unaltered despite variable levels of Se in the diet. Cellular immune response against bacteria P. multocida remained uninfluenced (P > 0.05), though an enhanced (P < 0.01) average antibody titer was noted in the group fed nutraceutical level of Se. Findings of the study suggest that supra-nutritional Se (0.53 ppm against 0.23 ppm) had a nutraceutical role and thus favoring humoral immune response, antioxidant status, blood monocyte percentage, and plasma Se levels in the healthy buffalo calves.

Interaction of Antioxidant Trace Minerals Affecting Blood Picture Including Antioxidant Profile of Healthy Buffalo (Bubalus bubalis) Calves.

Copper (Cu) and selenium (Se) are antioxidants and essential trace elements that have mutual interaction and are reported to have beneficial effects at supranutritional levels. The experiment was executed to evaluate the individual impact of supranutritional levels of targeted elements with the effect of their interactions in buffalo calves. Twenty male Murrah buffalo calves of about 8-9months (bodyweight 112.1 ± 7.69kg) were distributed into four groups of five calves in each group and fed either a control (C) diet or supplemented with supranutritional levels of Cu (T1), Se (T2), or combination of both (T3) for 120days. Higher (P = 0.015) values of packed cell volume were observed in group T2 at day 120; otherwise, all other hematological parameters remained comparable among groups. Over the period (day 120 vs. day 0), an enhancement in the percentage of lymphocytes (P = 0.006) with a reduction in neutrophils (P = 0.028) and hemoglobin (P = 0.024) values was observed in the control group. An enhancement in the percentage of monocytes (P = 0.031), with a reduced percentage of neutrophils (P = 0.022), was reported in groups T2 and T3, respectively. Interaction of Cu and Se at supranutritional level (T3) dramatically reduced plasma Cu (P = 0.008) level against the control values, with an improvement in Se markers (i.e., plasma Se, P = 0.041 and enzyme glutathione peroxidase, P = 0.057) over the values in calves fed supplemental Se alone (T2). Additionally, Cu (T1 and T3) was forced to decline (P < 0.05) Zn level in the plasma of buffalo calves. Cu (T1, P < 0.05) and Se (T2 and T3, P ≤ 0.01) supplementation was able to improve their respective plasma levels. The interaction of two trace elements at the supranutritional level further helped in reducing the lipid peroxidation (P = 0.01) values as well. Though antioxidant vitamins and cell-mediated immunity remained unaffected, humoral immunity against antigen P. multocida was high (P = 0.005) in the group T2. The conclusion may be drawn that supranutritional Cu and Se were capable to influence certain blood parameters with an additional interaction effect due to simultaneous supplementation in buffalo calves.

Supranutritional Maternal Organic Selenium Supplementation during Different Trimesters of Pregnancy Affects the Muscle Gene Transcriptome of Newborn Beef Calves in a Time-Dependent Manner.

Selenium (Se) is an essential micronutrient for growth and immune function in beef cattle. We previously showed that supranutritional maternal organic Se supplementation during late pregnancy improves immune function in their newborn calves; however, the effects of maternal organic Se-supplementation on fetal programming during different pregnancy stages have yet to be elucidated. Herein, we investigated the effects of supranutritional maternal organic Se-supplementation in different pregnancy trimesters on their beef calf’s genome-wide transcriptome profiles. Within 12 to 48 h of birth, whole blood and Longissimus dorsi (LD) muscle biopsies were collected from calves born to 40 crossbred Angus cows that received, except for the control group (CTR), Se-yeast boluses (105 mg of Se/wk) during the first (TR1), second (TR2), or third (TR3) trimester of gestation. Whole-blood Se concentrations of newborn calves increased from CTR, TR1, TR2 to TR3, whereas muscle Se concentrations of newborn calves were only increased in TR3 group. We identified 3048 unique differentially expressed genes (DEGs) across all group comparisons (FDR ≤ 0.05 and |log2FC| ≥ 1.5). Furthermore, we predicted 237 unique transcription factors that putatively regulate the DEGs. Independent of supplementation trimester, supranutritional maternal organic Se supplementation downregulated genes involved in adaptive immunity in all trimesters. Dependent on supplementation trimester, genes involved in muscle development were upregulated by TR3 Se supplementation and downregulated by TR1 Se-supplementation, and genes involved in collagen formation were downregulated by TR2 Se-supplementation. Supranutritional maternal organic Se supplementation in the last trimester of pregnancy resulted in upregulation of myosin and actin filament associated genes, potentially allowing for optimal muscle function and contraction. Our findings suggest a beneficial effect of supranutritional maternal organic Se supplementation during late gestation on Se-status and muscle development and function of newborn calves.

Supranutritional selenium suppresses ROS-induced generation of RANKL-expressing osteoclastogenic CD4+ Tcells and ameliorates rheumatoid arthritis.

ObjectiveThe benefit of Se supplementation in rheumatoid arthritis (RA) has been tested in clinical trials, but results remain inconclusive. The objective of this study was to specifically investigate the potential benefit of supranutritional Se by examining human samples from an area with supranutritional Se intake and testing a mouse model of RA.MethodsPeripheral blood mononuclear cells (PBMCs) from RA patients (N = 57) and healthy controls (HC, N = 71) from an area of supranutritional Se intake (Enshi, Hubei, China) were analysed by flow cytometry. Serum cytokine and Se levels were measured by cytometric beads array (CBA) and inductively coupled plasma mass spectrometry (ICP‐MS), respectively. With sufficient or supranutritional selenium intake, mice were induced with collagen‐induced arthritis (CIA) and examined for disease activity and immunopathology. The influence of Se supplementation in the generation of RANKL‐expressing osteoclastogenic CD4+ T cells was investigated by in vitro assays.ResultsIn Enshi city, HC showed the above‐normal concentrations of serum Se concentrations while RA patients were enriched in the normal range (70–150 ng mL−1) or below. RA patients with higher Se levels demonstrated milder disease and lower levels of C‐reactive protein, IL‐6, RANKL and Th17 cells. In the mouse CIA model, supranutritional Se supplementation delayed disease onset, ameliorated joint pathology and reduced CD4+CD44+RANKL+ T cells. Se supplementation could suppress RANKL expression in cultured mouse Th17 cells.ConclusionSupranutritional Se suppresses RANKL‐expressing osteoclastogenic CD4+ T cells and could be beneficial to RA, which warrants formal testing in randomised clinical trials.

Selenium metabolism and toxicity in the yeast Saccharomyces cerevisiae

Selenium (Se) is an essential trace element of considerable interest in humans from both a nutritional and a toxicological perspective because of the narrow margin between intakes that result in efficacy and toxicity. It is used as selenocysteine in a few selenoproteins with important physiological functions. Moreover, at supranutritional doses, Se-containing compounds have attracted interest as potential anticancer agents with high efficacy and selectivity against cancer cells. Thus, Se is becoming a widely used dietary supplement. However, accumulating evidence indicate that adverse health effects are associated with excess dietary supplementation. Therefore, characterizing the toxicity of Se metabolic intermediates are important steps to better understand both the beneficial and toxic mechanisms of Se. This review focuses on the metabolism of Se and the biological mechanisms explaining the toxicity of important Se-metabolites in the yeast Saccharomyces cerevisiae, which can be used as a model system to understand the mode of action and the biological effects of supranutritional Se in higher eukaryotes.

Feeding selenium-biofortified alfalfa hay during the preconditioning period improves growth, carcass weight, and nasal microbial diversity of beef calves.

We previously reported that feeding Se-biofortified alfalfa hay to weaned beef calves in a preconditioning program decreases morbidity and mortality during the feedlot period. To understand the mode of action by which supranutritional Se supplementation supports calf health, we examined the effect of agronomic Se-biofortification on nasal microbiome and fecal parasites. Recently weaned Angus-cross beef calves (n = 30) were randomly assigned to two groups and fed an alfalfa hay-based diet for 9 weeks in a preconditioning program. Alfalfa hay was harvested from fields fertilized with sodium selenate at a rate of 0 or 90 g Se/ha. Calculated Se intake from dietary sources was 1.09 and 27.45 mg Se/calf per day for calves consuming alfalfa hay with Se concentrations of 0.06 and 3.47 mg Se/kg dry matter, respectively. Feeding Se-biofortified alfalfa hay for 9 weeks was effective at increasing whole-blood Se concentrations (556 ± 11 vs 140 ± 11 ng/mL; P < 0.001) and increasing body weight (PTreatment, = 0.03) in weaned beef calves. Slaughter yield grades were higher for calves that had been fed Se-enriched alfalfa hay during the preconditioning period (PTreatment = 0.008). No significant differences were observed in fecal parasite load, which remained low. The nasal microbiome and microbiota diversity within calves and across calves expanded from weaning (week 0) to the feedlot period (week 12), which was promoted by feeding Se-biofortified alfalfa hay. Especially concerning was the expansion of nasal Mycoplasmataceae in the feedlot, which reached over 50% of the total microbiota in some calves. In conclusion, we identified dietary Se-biofortified alfalfa hay as a potential promoter of nasal microbiome genome and microbiota diversity, which may explain in part high-Se benefits for prevention of bovine respiratory disease complex in beef calves.

Antioxidant capacity, lipid oxidation status and expression of specific selenoprotein mRNA in Longissimus dorsi muscle of lambs (Ovies aries) supplemented with supranutritional selenium

Selenium is known to play a key role in maintenance of redox status of tissues, immunity, reproduction, thyroid and muscle functions. The present investigation was carried out to understand the effect of supranutritional dietary Se supplementation on antioxidant capacity, lipid oxidation and expression of specific selenoprotein mRNA in Longissimus dorsi muscles of growing lambs. Twenty male lambs of 5–6 months of age were fed basal diet supplemented with 0.5, 1.5 or 4.5 ppm Se-yeast (organic Se) or without Se (control) for 90 days. The antioxidant capacity, lipid oxidation of meat during different days of storage and the mRNA expression of GPX1, GPX2, GPX3, TXNRD1, TXNRD3, DIO1, DIO2, DIO3, SEPP1, SEP15 and SEPW1 were studied in Longissimus dorsi muscles of sheep. The results indicated improvement in antioxidant status by supplementation of 1.5 and 4.5 ppm Se, and reduction in meat lipid oxidation status on day 0 without any further reduction after 3 and 7 days of storage in all the Se supplemented lambs. A selective change in expression of GPX2, GPX3, TXNRD1, DIO2, DIO3, SEPP1, SEP15 and SEPW1 mRNA was observed by supranutritional Se while GPX1, TXNRD3, DIO1 and expressions remained unaffected by supplementation. In conclusion, supranutritional Se supplementation in lambs increased antioxidant status, reduced lipid oxidation status with limited effect on oxidative stability of meat during storage and regulated Longissimus dorsi muscle selenoprotein mRNA expression differentially depending on the Se feeding levels. Our results thus provided new insights into the regulation of selenoprotein gene expression by supranutritional levels of dietary Se.

Selenium and copper interaction at supra-nutritional level affecting blood parameters including immune response against P. multocida antigen in Murrah buffalo (Bubalus bubalis) calves

Minerals play important role in the diet of an animal. Bio-availability of minerals largely gets affected by absolute as well as the relative amount of each mineral present in the diet of an animal. Copper and selenium are two such an essential elements affect utilization of each other in the gastrointestinal tract. The present study elucidates the utilization of copper and selenium at supra-nutritional levels (higher than nutritional requirements). Male Murrah buffalo (Bubalus bubalis) calves (n = 10, 8–9 months, 111.7 ± 12.55 kg body weight) were divided equally into two groups and fed either a standard (Control) diet or the same diet supplemented with 0.3 ppm selenium (Se) and 10 ppm copper (Cu) (Treatment). Supplementation was made using liquid solutions of two inorganic mineral sources after mixing in the concentrate mixture and study lasts for a period of 80 days. Blood samples were collected just before starting supplementation (designated as 0 day of study) and at day 40 and 80 after starting supplementation. Blood samples were subjected to haematological parameters, plasma minerals and various oxidative stress-related parameters were determined with the cell-mediated and humoral immune response against antigen P. multocida (P52 strain). Supra-nutritional Se with Cu had higher blood monocytes (P < 0.05) and plasma selenium (P < 0.01) levels, while other hematological parameters and plasma minerals (except zinc, which was lower (P = 0.025) at day 80 in the treatment group) remained unaffected. Among markers for oxidative stress in blood, levels of lipid peroxidation were lesser (P < 0.01), at day 80 and overall mean values of the enzyme glutathione peroxidase and catalase were higher (P < 0.05) in the supra-nutritional group against control values. The overall mean activity of other oxidative stress markers including reduced glutathione, ceruloplasmin as well as the concentration of α tocopherol, retinol, and β carotene remained unaffected due to supra-nutritional Se and Cu. Although cell-mediated immune response remained comparable (P > 0.05) between groups, higher (P < 0.05) overall mean antibody titer values, as well as the values at day 80, was reported in supra-nutritional Se + Cu group. The study concluded that supra-nutritional Se with Cu in the ration of growing Murrah buffalo calves was helpful to reduce the oxidative stress and to enhance the humoral immune response. Simultaneously, higher plasma Se level and number of monocytes in blood highlighted the additional role of selenium and copper in a ration of growing buffalo calves as compared to its normal recommended dose.

Effects of feeding pregnant beef cows selenium-enriched alfalfa hay on passive transfer of ovalbumin in their newborn calves

Intestinal absorption of immunoglobulins is critical for health and survival of newborn calves because there is no transfer of immunoglobulins in utero. The objective of this study was to determine if feeding beef cows Se-enriched alfalfa hay during the last trimester of gestation improves passive transfer of ovalbumin (OVA), a surrogate protein marker for IgG absorption. Control cows (n = 15) were fed non-Se-fortified alfalfa hay (5.3 mg Se/head daily) plus a mineral supplement containing inorganic Se (3 mg Se/head daily). Med-Se (n = 15) and High-Se cows (n = 15) were fed Se-biofortified alfalfa hay (27.6 and 57.5 mg Se/head daily, respectively); both groups received mineral supplement without added Se. Calves were randomly assigned to receive orally administered OVA at 12, 24, or 36 h of age. Calves that received their oral dose of OVA at 12 h of age had higher serum OVA concentrations across the first 48 h of life if born to High-Se cows compared to calves born to Control cows (P = 0.05), with intermediate values for calves born to Med-Se cows. Our results, using OVA as a model for passive transfer, suggest that if calves do not receive adequate colostrum to reach maximum pinocytosis, then supranutritional Se supplementation in beef cattle may improve passive transfer in their calves, if calves receive colostrum within the first 12 h of age.

Improvement of flesh quality in rainbow trout (Oncorhynchus mykiss ) fed supranutritional dietary selenium yeast is associated with the inhibited muscle protein degradation

Supranutritional dietary selenium (Se) has been demonstrated beneficial for fish health, however, its effects on fish flesh quality remain unclear. This study investigated the effects of supranutritional dietary Se on the flesh quality of rainbow trout (Oncorhynchus mykiss) and their potential mechanism. Fish were fed a basal diet supplemented with or without graded Se yeast for 10 weeks. Results showed that Se supplementation significantly increased fillet crude protein and enhanced fillet water-holding capacity as well as fillet firmness. Supplementing with both 2 and 4 mg/kg Se significantly downregulated the expressions of two autophagy–lysosome-related genes (autophagy-related 12-like and gamma-aminobutyric acid type A receptor-associated protein-like 1) in fish muscle, while supplementing with 4 mg/kg Se also significantly downregulated the expression of two ubiquitin–proteasome-related genes (muscle RING finger 2 and F-box protein 25). Correlation analysis indicated that the improved fillet quality parameters were closely correlated with the expressions of these differentially expressed genes. This study revealed that dietary Se was effective for the improvement of rainbow trout flesh quality, and the improved fish flesh quality was associated with the inhibited protein degradation in fish muscle.

Ameliorative Effects of Selenium on Cadmium-Induced Injury in the Chicken Ovary: Mechanisms of Oxidative Stress and Endoplasmic Reticulum Stress in Cadmium-Induced Apoptosis.

Despite the well-established toxicity of cadmium (Cd) to animals and the ameliorative effects of selenium (Se), some specific mechanisms in the chicken ovary are not yet clarified. To explore the mechanism by which the toxicity effect of Cd is induced and explore the effect of supranutritional Se on Cd toxicity in female bird reproduction, forty-eight 50-day-old Isa Brown female chickens were divided randomly into four groups. Group I (control group) was fed the basic diet containing 0.2mg/kg Se. Group II (Se-treated group) was fed the basic diet supplemented with sodium selenite (Na2SeO3), and the total Se content was 2mg/kg. Group III (Se + Cd-treated group) was fed the basic diet supplemented with Na2SeO3; the total Se content was 2mg/kg, and it was supplemented with 150mg/kg cadmium chloride (CdCl2). Group IV (Cd-treated group) was with the basic diet supplemented with 150mg/kg CdCl2. The Cd, estradiol (E2), and progestogen (P4) contents changed after subchronic Cd exposure in chicken ovarian tissue; subsequently, oxidative stress occurred and activated the endoplasmic reticulum (ER) pathway to induce apoptosis. Further, Se decreased the accumulation of Cd in ovarian tissue, increased the E2 and P4 contents, alleviated oxidative stress, and reduced apoptosis via the ER stress pathway. The present results demonstrated that Cd could induce apoptosis via the ER stress pathway in chicken ovarian tissue and that Se had a significant antagonistic effect. These results are potentially valuable for finding a strategy to prevent Cd poisoning.

Effects of a short-term supranutritional selenium supplementation on redox balance, physiology and insulin-related metabolism in heat-stressed pigs.

Heat stress (HS) disrupts redox balance and insulin-related metabolism. Supplementation with supranutritional amounts of selenium (Se) may enhance glutathione peroxidase (GPX) activity and reduce oxidative stress, but may trigger insulin resistance. Therefore, the aim of this experiment was to investigate the effects of a short-term high Se supplementation on physiology, oxidative stress and insulin-related metabolism in heat-stressed pigs. Twenty-four gilts were fed either a control (0.20ppm Se) or a high Se (1.0ppm Se yeast, HiSe) diet for 2weeks. Pigs were then housed in thermoneutral (20°C) or HS (35°C) conditions for 8days. Blood samples were collected to study blood Se and oxidative stress markers. An oral glucose tolerance test (OGTT) was conducted on day 8 of thermal exposure. The HS conditions increased rectal temperature and respiration rate (both p<.001). The HiSe diet increased blood Se by 12% (p<.05) and ameliorated the increase in rectal temperature (p<.05). Heat stress increased oxidative stress as evidenced by a 48% increase in plasma advanced oxidized protein products (AOPPs; p<.05), which may be associated with the reductions in plasma biological antioxidant potential (BAP) and erythrocyte GPX activity (both p<.05). The HiSe diet did not alleviate the reduction in plasma BAP or increase in AOPPs observed during HS, although it tended to increase erythrocyte GPX activity by 13% (p=.068). Without affecting insulin, HS attenuated lipid mobilization, as evidenced by a lower fasting NEFA concentration (p<.05), which was not mitigated by the HiSe diet. The HiSe diet increased insulin AUC, suggesting it potentiated insulin resistance, although this only occurred under TN conditions (p=.066). In summary, HS induced oxidative stress and attenuated lipid mobilization in pigs. The short-term supranutritional Se supplementation alleviated hyperthermia, but did not protect against oxidative stress in heat-stressed pigs.

Supranutritional selenium intake from enriched milk casein impairs hepatic insulin sensitivity via attenuated IRS/PI3K/AKT signaling and decreased PGC-1α expression in male Sprague–Dawley rats

Selenium (Se)-enriched milk provides antioxidant benefits and has therapeutic potential against cancer. However, both antidiabetic and prodiabetic effects have been attributed to Se. Our objective was to evaluate the effect of Se-enriched milk casein on insulin sensitivity in rats when given at the requirement of 0.25 ppm Se and supranutritionally on both low- and high-fat diets. Two hundred sixteen male Sprague–Dawley rats were fed low- or high-fat diets containing one, two or eight times the Se requirement in a randomized block design. After 7 weeks, 72 rats were subjected to the hyperinsulinemic–euglycemic clamp with [3-3H]glucose infusion to estimate glucose fluxes. Tissues were collected from the remaining 144 rats 8 min after ip saline or insulin injection. During hyperinsulinemic–euglycemic clamps, glucose infusion rate was 22% lower (P=.058), and endogenous glucose production was 76% higher (P=.054) when Se content increased from one to eight times the requirement on low-fat diets, indicating impaired hepatic insulin sensitivity. Se also decreased the ability for insulin to stimulate Akt phosphorylation at Thr308. Hepatic oxidation state and expression of selenoprotein P and glutathione peroxidase-1 were unaffected while expression of insulin receptor substrate (IRS)-1 and−2 and PPARγ coactivator-1α (PGC-1α) decreased with supranutritional Se and high-fat intake. In addition, hepatic expression of regulatory and catalytic subunits of phosphatidylinositol 3-kinase (PI3K) decreased with supranutritional intake of Se. Se intake from enriched casein up to eight times the requirement impairs hepatic insulin sensitivity in a mechanism similar to fat feeding, via attenuated IRS/PI3K/Akt signaling and decreased PGC-1α expression.

The supranutritional selenium status alters blood glucose and pancreatic redox homeostasis via a modulated selenotranscriptome in chickens (Gallus gallus)

Dietary Se status stabilizes pancreatic normal physiology functionviathe regulation of the selenoprotemic transcriptions. Supranutritional or excess Se status alters the pancreatic redox homeostasisviamodulated selenotranscriptome.

Impact of DDGS-supplemented diet with or without vitamin E and selenium supplementation on the fatty acid profile of beef

Abstract The impact of supplementation of vitamin E or organic selenium in DDGS (dried distillers grains with solubles) diet on fatty acid composition in two meat cuts of finishing Holstein bulls was investigated. Twenty-four Holstein bulls were allotted to treatments in three groups of eight bulls per group for a 100-day trial. The treatments were adequate Se and vitamin E supplementation in control group (C), supranutritional vitamin E supplementation in vitamin Group E (E), supranutritional Se supplementation in selenium group (Se). At similar age, slaughtering Group C had higher slaughter/carcass weight and EUROP fat score than Se counterparts. The killing out percentage and proximate composition of muscles differed among treatments. Inclusion of the vitamin E or Se supplement led to expected increases (P &lt; 0.05) in vitamin E and Se contents of the brisket and loin. Higher vitamin E concentration caused significant lower SFA and greater PUFA. Higher Se level influenced significant SFA in brisket and PUFA in both muscles. Vitamin E or Se dietary treatments in DDGS-supplemented diet resulted in beef meat cuts considerably beneficial PUFA/SFA but markedly higher n-6/n-3 PUFA ratio and even higher health index in both meat samples opposite to Group C.