Selenoproteins and maternal nutrition

Organic selenium and vitamin E for gilts and sows bred in equatorial climate

The aim of this study was to evaluate the dietary supplementation of organic selenium (Se) and vitamin E for sows from 1st and 2nd parity order, without adiabatic cooling on physiological parameters, reproductive performance, milk composition, litter performance and blood concentrations of antioxidant enzymes. A total of 96 sows were allotted in a 4 × 2 completely factorial design, with 4 experimental groups and 2 parity orders (1st and 2nd). The experimental groups consisted of: ACCon-sows receiving adiabatic cooling and no dietary supplementation of organic Se and vitamin E; WACCon-sows without adiabatic cooling and no dietary supplementation of organic Se and vitamin E; WACSe-sows without adiabatic cooling with dietary supplementation of 0.3 mg/kg organic Se; WACSeE-sows without adiabatic cooling with dietary supplementation of 0.3 mg/kg organic Se and 90 UI of vitamin E. ACCon Sows had lower respiratory rate, rectal temperature and body surface temperature when compared to the others sows (p < 0.05). Sows without evaporative cooling had lower daily milk production and weaned litters with lower weight and average daily gain when compared to the other groups (p < 0.05). ACCon sows presented higher weaned piglets to WACSeE sows. WACSeE Sows had higher concentrations of GSH-Px when compared to other experimental groups and higher levels of SOD than sows from ACCon and WACSe. Piglets of sows from WACSeE group presented higher levels of GSH-Px and SOD when compared to the other experimental groups. ACCon sows have higher milk yield and higher litter weight than others groups. Under equatorial climate conditions, dietary supplementation of organic Se and vitamin E from first and second parity order sows does not respond efficiently on thermoregulatory physiology and performance compared to adiabatic cooling, but modulates the enzymatic antioxidant balance of sows and piglets.

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.

Organoselenium Compounds: Chemistry and Applications in Organic Synthesis

Selenium, originally described as a toxin, turns out to be a crucial trace element for life that appears as selenocysteine and its dimer, selenocystine. From the point of view of drug developments, selenium-containing drugs are isosteres of sulfur and oxygen with the advantage that the presence of the selenium atom confers antioxidant properties and high lipophilicity, which would increase cell membrane permeation leading to better oral bioavailability. In this article, we have focused on the relevant features of the selenium atom, above all, the corresponding synthetic approaches to access a variety of organoselenium molecules along with the proposed reaction mechanisms. The preparation and biological properties of selenosugars, including selenoglycosides, selenonucleosides, selenopeptides, and other selenium-containing compounds will be treated. We have attempted to condense the most important aspects and interesting examples of the chemistry of selenium into a single article.

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

Background

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

Methods

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

Results

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

Conclusion

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

Maternal supplementation of nano-selenium in a plant-based diet improves antioxidant competence of female Arabian yellowfin sea bream (Acanthopagrus arabicus) breeders and their progeny

Antioxidants such as selenium (Se) play vital roles in reproduction success and larval development in fish. A three-month feeding experiment was conducted to examine the impact of enriching a plant-based diet (60% of fishmeal was substituted with a blend of plant ingredients) with nano-selenium (nano-Se) on antioxidant metabolism in female brooders and the progeny of Arabian yellowfin sea bream (Acanthopagrus arabicus). At this point, the plant-based diet was supplemented with graded levels of nano-Se at 0, 0.5, 1, 2, and 4 mg/Kg diet. Moreover, a fishmeal-based diet served as a positive control (FMD-Control). Broodfish were randomly distributed into eighteen 10 m³ rectangular concrete tanks (8 males and 8 females in each tank). Each experimental diet was subjected to three replications. Selenium retention increased in the serum, liver, ovary, eggs, and three-day larvae with increasing dietary nano-Se levels (P < 0.05). Supplementing the plant-based diet with 2-4 mg nano-Se/Kg significantly enhanced normal embryogenesis, fertilization, hatching, and larval survival rates. Generally, fish fed on plant-based diets with lower nano-Se supplementation (0-0.5 mg/Kg) had higher catalase and superoxide dismutase activities in the liver, ovaries, eggs, and larvae compared to the other groups. Glutathione peroxidase activity and total antioxidant capacity markedly increased, whereas lipid peroxidation decreased in the liver, ovary, serum, eggs, and progeny of broodfish fed with nano-Se supplemented diets (P < 0.05). In conclusion, supplementation of 2-4 mg nano-Se /Kg in a plan-based feed is recommended for the improvement of antioxidant defense in female A. arabicus brooders and their progeny.

The Importance of Dietary Antioxidants on Oxidative Stress, Meat and Milk Production, and Their Preservative Aspects in Farm Animals: Antioxidant Action, Animal Health, and Product Quality-Invited Review

The biological effects of oxidative stress and associated free radicals on farm animal performance, productivity, and product quality may be managed via dietary interventions-specifically, the provision of feeds, supplements, and forages rich in antioxidants. To optimize this approach, it is important first to understand the development of free radicals and their contributions to oxidative stress in tissue systems of farm animals or the human body. The interactions between prooxidants and antioxidants will impact redox homeostasis and, therefore, the well-being of farm animals. The impact of free radical formation on the oxidation of lipids, proteins, DNA, and biologically important macromolecules will likewise impact animal performance, meat and milk quality, nutritional value, and longevity. Dietary antioxidants, endogenous antioxidants, and metal-binding proteins contribute to the 'antioxidant defenses' that control free radical formation within the biological systems. Different bioactive compounds of varying antioxidant potential and bio-accessibility may be sourced from tailored feeding systems. Informed and successful provision of dietary antioxidants can help alleviate oxidative stress. However, knowledge pertaining to farm animals, their unique biological systems, and the applications of novel feeds, specialized forages, bioactive compounds, etc., must be established. This review summarized current research to direct future studies towards more effective controls for free radical formation/oxidative stress in farm animals so that productivity and quality of meat and milk can be optimized.

Binge drinking during the adolescence period causes oxidative damage-induced cardiometabolic disorders: A possible ameliorative approach with selenium supplementation

Binge drinking (BD) is the most common alcohol consumption model among adolescents. BD exposure during adolescence disrupts the nervous system function, being involved in the major mortality causes at this age: motor vehicle accidents, homicides and suicides. Recent studies have also shown that BD consumption during adolescence affects liver, renal and cardiovascular physiology, predisposing adolescents to future adult cardiometabolic damage. BD is a particularly pro-oxidant alcohol consumption pattern, because it leads to the production of a great source of reactive oxygen species (ROS) via the microsomal ethanol oxidizing system, also decreasing the antioxidant activity of glutathione peroxidase (GPx). Selenium (Se) is a mineral which plays a pivotal role against oxidation; it forms part of the catalytic center of different antioxidant selenoproteins such as GPxs (GPx1, GPx4, GPx3) and selenoprotein P (SelP). Specifically, GPx4 has an essential role in mitochondria, preventing their oxidation, apoptosis and NFkB-inflamative response, being this function even more relevant in heart's tissue. Se serum levels are decreased in acute and chronic alcoholic adult patients, being correlated to the severity of oxidation, liver damage and metabolic profile. Experimental studies have described that Se supplementation to alcohol exposed mice clearly decreases oxidative and liver damage. However, clinical BD effects on Se homeostasis and selenoproteins' tissue distribution related to oxidation during adolescence are not yet studied. In this narrative review we will describe the use of sodium selenite supplementation as an antioxidant therapy in adolescent BD rats in order to analyze Se homeostasis implication during BD exposure, oxidative balance, apoptosis and inflammation, mainly in liver, kidney, and heart. These biomolecular changes and the cardiovascular function will be analyzed. Se supplementation therapies could be a good strategy to prevent the oxidation, inflammation and apoptosis generated in tissues by BD during adolescence, such as liver, kidney and heart, improving cardiovascular functioning.

Relation between Selenium and Female Fertility: A Systematic Review

OBJECTIVE

 To analyze the influence of selenium in female fertility.

DATA SOURCE

 A search was performed in the following databases: MEDLINE, Web of Science, Scopus, SciELO, LILACS, MDPI, ScienceDirect, and Europe PMC. The descriptors selected were "selenium" AND "female" AND "fertility". The search interval was from 1996 to 2021.

STUDY SELECTION

 The evaluation was performed independently by two reviewers, and a third reviewer confirmed the inclusion of papers in case of divergence between the first two reviewers. Papers were selected after the title and abstract were read, and those that met the eligibility criteria had the full text read.

DATA COLLECTION

 The following data was extracted: author, year of publication, country, type of study, objective, method, sample size, follow-up period, patients' mean age, inclusion and exclusion criteria, and concentration of serum and capillary selenium. The data was organized in chronological order of paper publication.

DATA SYNTHESIS

 The number of papers identified totaled 3,800, out of which 7 were included in the systematic review. The studies indicated a positive correlation between serum selenium and antioxidant concentration in the follicular fluid, reduction in antithyroid antibodies, oocyte production and follicle number.

CONCLUSION

 Selenium supplementation is promising in women with this micronutrient deficiency to promote improvement of the reproductive efficiency and prevent damage to the pregnancy. Further studies on this theme are still required.

Selenium Supplementation in Pregnancy-Maternal and Newborn Outcomes

Background. Several studies have suggested that increased oxidative stress during pregnancy may be associated with adverse maternal and foetal outcomes. As selenium is an essential mineral with an antioxidant role, our aim was to perform a systematic review of the existing literature reporting the effects of selenium supplementation during pregnancy on maternal and neonatal outcomes. Materials and Methods. Six electronic databases (Medline, Embase, Cochrane Library, Web of Science, Scopus, and PubMed) were searched for studies reporting the effects of selenium supplementation during pregnancy and the postpartum period on maternal and neonatal outcomes. Only randomised controlled trials on human subjects reported in English and published up to October 2021 were included. Quality assessments were conducted using the modified Downs and Black quality assessment tool. Data were extracted using a narrative synthesis. Results. Twenty-two articles were included in our systematic review (seventeen reported on maternal outcomes, two on newborn outcomes, and three on both). Maternal studies reported the effects of selenium supplementation in the prevention of thyroid dysfunction, gestational diabetes, pregnancy-induced hypertension/preeclampsia, oxidative stress, postpartum depression, premature rupture of membranes, intrauterine growth retardation, breastmilk composition, and HIV-positive women. Newborn studies reported the effects of maternal selenium supplementation on foetal oxidation stress, foetal lipid profile, neonatal hyperbilirubinemia, and newborn outcomes in HIV-positive mothers. The majority of studies were inappropriately designed to establish clinical or scientific utility. Of interest, four studies reported that selenium supplementation reduced the incidence of thyroid dysfunction and permanent hypothyroidism during the postpartum period by reducing thyroid peroxidase and thyroglobulin antibody titres. Conclusion. The evidence supporting selenium supplementation during pregnancy is poor and there is a need for appropriately designed randomised controlled trials before routine use can be recommended.

The Selenium Yeast vs Selenium Methionine on Cell Viability, Selenoprotein Profile and Redox Status via JNK/ P38 Pathway in Porcine Mammary Epithelial Cells

Comprehensive studies have been conducted to compare the effect of organic and inorganic selenium previously, but there is still limited knowledge about the difference between organic selenium (Se) from varied sources despite the widely use of organic Se in both animal and human being nutrient additives. In the present study, we systemically compared the effect of two different types of organic Se including selenium yeast (SeY) and selenium methionine (Sel-Met) on cell viability, selenoprotein transcriptome, and antioxidant status in porcine mammary epithelial cells (PMECs) and the results indicated that appropriate addition of SeY and Sel-Met both significantly promoted cell viability and up-regulated the mRNA expression of most selenopreoteins including DIOs, GPXs, and TrxRs family et al. (P < 0.05). Besides, two different sources of Se supplementation both greatly improved redox status with higher levels of T-AOC, SOD, and CAT (P < 0.05), while less content of MDA (P < 0.05), and reduced protein expression of cleaved-caspase-3 (P < 0.05) to mitigate cell apoptosis. Furthermore, the key proteins related to p38/JNK pathway including p38, p-p38, JNK, and p-JNK were apparently reduced in the groups with both of SeY and Sel-Met (P < 0.05). Interestingly we found that the changes induced by SeY supplementation in cell viability, selenoprotein transcriptome, antioxidative capacity, and anti-apoptosis were comprehensively greater compared with same levels addition of Sel-Met in PEMCs (P < 0.05). In conclusion, both SeY and Sel-Met promoted cell viability and attenuated cell apoptosis by regulating the selenoprotein expression and antioxidative capacity via p38/JNK signaling pathway in PMEC, but SeY has more efficient benefits than that of Sel-Met.

Effects of dietary supplementation of different sources and levels of selenium on the semen quality and reproductive performance in aged broiler breeder roosters

Fertility has a great impact on economic outcome in poultry sector. However, several physiological stressors such as aging adversely affected fertilization capacity and hatching quantity and quality. This study investigated the effect of dietary supplementation of different sources and levels of inorganic and organic selenium on the semen quality and reproductive performance of aged broiler breeder roosters. A total of thirty-six 50-wk-old Ross 308 roosters were randomly allocated to 6 groups and fed with different levels of organic and inorganic selenium. Treatments were included in the basal diet (control: CG), dietary supplementation of 0.15 (SeY0.15), 0.30 (SeY0.30), and 0.45 (SeY0.45) mg/kg selenium-enriched yeast (SeY), dietary supplementation of 0.30 mg/kg commercial organic selenium (Selemax), and dietary supplementation of 0.30 mg/kg sodium selenite (SS) as an inorganic source during 12 consecutive weeks. Ejaculated volume, semen quality attributes of the collected semen samples were evaluated every week.

To assess fertility, hatchability and the hatched chick quality, the semen samples collected during last 2 wk of the trial were used to artificial insemination of hens. In order to measure seminiferous tube diameter and seminiferous epithelium thickness, testicular histology was also performed at the end of the experiment. Sperm motility, plasma membrane functionality and integrity, and ejaculation volume were higher in the SeY0.45 group compared to the other groups (P < 0.05). Fertility and hatchability rate as well as seminiferous epithelium thickness and seminiferous tube diameter were improved in the SeY0.45 compared with CG, SeY0.15 and SS groups (P < 0.05). Also hatchelling quality from roosters with SeY0.45 was higher than CG and SS groups (P < 0.05). No significant differences were noted in embryonic mortality between groups (P > 0.05).

In conclusion, dietary supplementation of 0.45 mg SeY improved sperm quality and reproductive performance of aged broiler breeder roosters.

Maternal malnutrition and anaemia in India: dysregulations leading to the 'thin-fat' phenotype in newborns

Maternal and child malnutrition and anaemia remain the leading factors for health loss in India. Low birth weight (LBW) offspring of women suffering from chronic malnutrition and anaemia often exhibit insulin resistance and infantile stunting and wasting, together with increased risk of developing cardiometabolic disorders in adulthood. The resulting self-perpetuating and highly multifactorial disease burden cannot be remedied through uniform dietary recommendations alone. To inform approaches likely to alleviate this disease burden, we implemented a systems-analytical approach that had already proven its efficacy in multiple published studies. We utilised previously published qualitative and quantitative analytical results of rural and urban field studies addressing maternal and infantile metabolic and nutritional parameters to precisely define the range of pathological phenotypes encountered and their individual biological characteristics. These characteristics were then integrated, via extensive literature searches, into metabolic and physiological mechanisms to identify the maternal and foetal metabolic dysregulations most likely to underpin the ‘thin-fat’ phenotype in LBW infants and its associated pathological consequences. Our analyses reveal hitherto poorly understood maternal nutrition-dependent mechanisms most likely to promote and sustain the self-perpetuating high disease burden, especially in the Indian population. This work suggests that it most probably is the metabolic consequence of ‘ill-nutrition’ – the recent and rapid dietary shifts to high salt, high saturated fats and high sugar but low micronutrient diets – over an adaptation to ‘thrifty metabolism’ which must be addressed in interventions aiming to significantly alleviate the leading risk factors for health deterioration in India.

Role for Selenium in Metabolic Homeostasis and Human Reproduction

Selenium (Se) is a micronutrient essential for life. Dietary intake of Se within the physiological range is critical for human health and reproductive functions. Selenium levels outside the recommended range have been implicated in infertility and variety of other human diseases. However, presently it is not clear how different dietary Se sources are processed in our bodies, and in which form or how much dietary Se is optimum to maintain metabolic homeostasis and boost reproductive health. This uncertainty leads to imprecision in published dietary guidelines and advice for human daily intake of Se and in some cases generating controversies and even adverse outcomes including mortality. The chief aim for this review is to describe the sources of organic and inorganic Se, the metabolic pathways of selenoproteins synthesis, and the critical role of selenprotenis in the thyroid gland homeostasis and reproductive/fertility functions. Controversies on the use of Se in clinical practice and future directions to address these challenges are also described and discussed herein.

Effects of Selenomethionine on Cell Viability, Selenoprotein Expression and Antioxidant Function in Porcine Mammary Epithelial Cells

This study investigated the effects of selenomethionine (Se-Met) on the cell viability, selenoprotein expression, and antioxidant function of porcine mammary epithelial cells (pMECs) to reveal the underlying molecular mechanism of Se-Met on the lactation performance and antioxidant capacity of sows in vitro. The pMECs were used as an in vitro model and were treated with various concentrations of Se-Met (0, 0.5, 1, 2, and 4 μM). Cells were analyzed for cell viability, selenoprotein transcriptome, selenoprotein expression, and antioxidant enzyme activities. The results showed that, with increasing Se-Met concentrations, cell viability first increased and then decreased at 24, 48, or 72 h posttreatment with maximum values at 0.5-μM Se-Met. As the Se-Met concentrations increased, the mRNA expression of 17 selenoproteins first upregulated and then downregulated, with maximum values at 0.5-μM Se-Met. The 17 selenoproteins included SEPHS2, SELENOP, GPX1, GPX2, GPX3, GPX6, TXNRD1, SELENOK, SELENOW, DIO1, DIO2, DIO3, SELENOF, SELENOS, SELENOH, SELENOI, and SELENOT. Additionally, the protein expression levels of SEPHS2, SELENOP, GPX1, and TXNRD1 and the activities of glutathione peroxidase and thioredoxin were highest at 0.5-μM Se-Met. In conclusion, 0.5-μM Se-Met promotes cell viability partially by improving selenoprotein expression and antioxidant function in pMECs, which provides evidence for the potential ability of Se-Met to improve mammary gland health in sows.

Hydroxyapatite nanophases augmented with selenium and manganese ions for bone regeneration: Physiochemical, microstructural and biological characterization

Hydroxyapatite (HAP) nanopowders with different manganese (Mn) and selenium (Se) contents with Mn/Ca and Se/P molar ratio of 1 mol%, 2.5 mol% and 5 mol% were synthesized by wet-co-chemical precipitation method. The results revealed that with either Mn or Se doping, ion-substituted apatite phase was achieved with good crystallographic features. The combined evidence obtained from spectrometric techniques revealed that nanocrystalline HAP was effectively doped with Mn and Se ions, where Se in form of SeO₃^2- replaced PO₄^3- and Mn²⁺ replaced Ca²⁺. Mn and Se doped HAP samples exhibited rod-like and needle-like morphology with strong tendency to form agglomerates. HAP enriched with Mn and Se represented a strong antibacterial effect and also showed prominent blood compatibility. From the biocompatibility testing, it was evident that Mn and Se doped HAP augmented the osteoblasts adhesion, migration and proliferation in a dose-dependent manner. To conclude from this study, it is clearly evident that the doping amount of both Mn and Se ions can determine the size and morphology of the final HAP product. Therefore, Mn and Se HAP nanopowders with molar ratio less than 5 mol% without any heat treatment can provide good crystallographic features to HAP with satisfying micro-structural, thermal and biological properties.

A comprehensive review on the neuropathophysiology of selenium

As an essential micronutrient, selenium (Se) exerts its biological function as a catalytic entity in a variety of enzymes. From a toxicological perspective, however, Se can become extremely toxic at concentrations slightly above its nutritional levels. Over the last few decades, there has been a growing level of concern worldwide regarding the adverse effects of both inorganic and organic Se compounds on a broad spectrum of neurological functions. A wealth of evidence has shown that exposure to excess Se may compromise the normal functioning of various key proteins, neurotransmitter systems (the glutamatergic, dopaminergic, serotonergic, and cholinergic systems), and signaling molecules involved in the control and regulation of cognitive, behavioral, and neuroendocrine functions. Elevated Se exposure has also been suspected to be a risk factor for the development of several neurodegenerative and neuropsychiatric diseases. Nonetheless, despite the various deleterious effects of excess Se on the central nervous system (CNS), Se neurotoxicity and negative behavioral outcomes are still disregarded at the expense of its beneficial health effects. This review focuses on the current state of knowledge regarding the neurobehavioral effects of Se and discusses its potential mode of action on different aspects of the central and peripheral nervous systems. This review also provides a brief history of Se discovery and uses, its physicochemical properties, biological roles in the CNS, environmental occurrence, and toxicity. We also review potential links between exposure to different forms of Se compounds and aberrant neurobehavioral functions in humans and animals, and identify key knowledge gaps and hypotheses for future research.

Short Communication: Effects of Dietary Selenium Supplementation on Selenium Deposition and Antioxidant Status in Postpartum Mice

This study aimed to investigate the effects of dietary selenium during pregnancy on the selenium deposition and antioxidant enzymes in postpartum mouse serum, liver, and mammary gland. Eighty BALB/c pregnant mice were randomly divided into four groups: CG (Se-deficient basal diet, n = 20), LG (0.05 mg/kg Se-supplemented diet, n = 20), MG (0.1 mg/kg Se-supplemented diet, n = 20), and HG (0.2 mg/kg Se-supplemented diet, n = 20). Four days after parturition, all mice were euthanized. The selenium deposition and antioxidants enzymes in serum, liver, and mammary gland were detected. Results show that with increasing selenium supplementation, the selenium deposition and activation of T-AOC, T-SOD, and GSH-Px increased, meanwhile the concentration of MDA decreased in serum, liver, and mammary gland. Therefore, this study suggested selenium was mainly deposited in the liver, and dietary selenium during pregnancy might improve the antioxidant status in postpartum animals.

Effect of maternal organic selenium supplementation during pregnancy on sow reproductive performance and long-term effect on their progeny

Selenium (Se) is an essential trace element for animals and exists in nature in both inorganic and organic forms. Although organic Se is more bioavailable than inorganic Se, there are inconsistent reports on the effect of organic Se on the reproductive performance of sows. This study was conducted to investigate the effect of maternal organic Se (2-hydroxy-4-methylselenobutanoic [HMSeBA]) supplementation on reproductive performance and antioxidant capacity of sows, and the long-term effect on the growth performance and antioxidant capacity of their offspring with or without lipopolysaccharide (LPS) challenge. The experimental design used in this study was a completely randomized design; 45 Landrace × Yorkshire sows were randomly allocated to receive one of the following three diets during gestation: control diet (Control, basal diet, n = 15), sodium selenite (Na2SeO3)-supplemented diet (Na2SeO3, basal diet + 0.3 mg Se/kg Na2SeO3, n = 15), and HMSeBA-supplemented diet (HMSeBA, basal diet + 0.3 mg Se/kg HMSeBA, n = 15). On day 21 of age, male offspring from each group were injected with LPS or saline (n = 6). As compared with the control group, maternal HMSeBA supplementation increased the number of total born piglets, while decreased birth weight (P < 0.05). In the first week of lactation, maternal HMSeBA supplementation increased litter weight gain compared with the Na2SeO3 group (P < 0.05) and increased the average daily gain of piglets compared with the control group and Na2SeO3 group (P < 0.05). Meanwhile, maternal HMSeBA supplementation decreased piglet birth interval as compared with the control group and Na2SeO3 group (P < 0.05). Besides, plasma glutathione peroxidase (GSH-Px) activity was higher in the HMSeBA group on farrowing 0 min and 90 min, while malondialdehyde (MDA) concentration was lower on farrowing 0, 90, and 135 min than those in the control group (P < 0.05). In addition, maternal HMSeBA supplementation increased the concentration of selenoprotein P (SELENOP) in colostrum compared with the control group (P < 0.05). Further study revealed that the LPS-challenged HMSeBA group had higher GSH-Px and total antioxidant capacity and lower MDA in weaning piglets compared with the LPS-challenged control group (P < 0.05). Taken together, maternal HMSeBA supplementation increased the number of total born piglets, shortened the duration of farrowing, improved the antioxidant capacities of sows and their offspring, and improved the growth performance of suckling pigs at the first week of lactation. Thus, HMSeBA supplementation during gestation has the potentiality to produce more kilogram of meat.

Nutritional significance of amino acids, vitamins and minerals as nutraceuticals in poultry production and health - a comprehensive review

Nutraceuticals have gained immense importance in poultry science recently considering the nutritional and beneficial health effects of their constituents. Besides providing nutritional requirements to birds, nutraceuticals have beneficial pharmacological effects, for example, they help in establishing normal physiological health status, prevent diseases and thereby improve production performance. Nutraceuticals include amino acids, vitamins, minerals, enzymes, etc. which are important for preventing oxidative stress, regulating the immune response and maintaining normal physiological, biochemical and homeostatic mechanisms. Nutraceuticals help in supplying nutrients in balanced amounts for supporting the optimal growth performance in modern poultry flocks, and as a dietary supplement can reduce the use of antibiotics. The application of antibiotic growth enhancers in poultry leads to the propagation of antibiotic-resistant microbes and drug residues; therefore, they have been restricted in many countries. Thus, there is a demand for natural feed additives that lead to the same growth enhancement without affecting the health. Nutraceuticals substances have an essential role in the development of the animals' normal physiological functions and in protecting them against infectious diseases. In this review, the uses of amino acids, vitamins and minerals as well as their mode of action in growth promotion and elevation of immune system are discussed.

Selenium Deficiency in Chickens Induces Intestinal Mucosal Injury by Affecting the Mucosa Morphology, SIgA Secretion, and GSH-Px Activity

The small intestine is one of the target organs of dietary selenium (Se) deficiency. Our objective was to investigate the effects of Se deficiency on small intestinal mucosa morphology and function in chickens. In the present study, 1-day (d)-old chickens were fed either a commercial diet with 0.15 mg/kg Se (control group) or a Se-deficient diet with 0.016 mg/kg Se (Se-group). The average daily weight gain, Se content in the blood, secretory immunoglobulin A (SIgA) secretion, and glutathione peroxidase (GSH-Px) activity in the small intestine in chickens were examined after 10, 20, 30, and 40 days of feeding. We also observed the morphology of the small intestine and recorded the number of intraepithelial lymphocytes (IELs). The average daily weight gain decreased; the level of Se in the blood decreased significantly; and SIgA secretion and GSH-Px activity in the duodenum, jejunum, and ileum decreased to different degrees. Histological analysis showed that the villus length, crypt depth, mucosal thickness, and number of IELs in the small intestine decreased to different extents in different periods. In the Se-group, longer feeding times were associated with more severe injury to physiological structure and function in the intestinal mucosa in chickens. In conclusion, Se deficiency induced injury of the mucosal immune barrier and physical barrier of the small intestine, and decreased the growth performance and antioxidant capacity in chickens.

The effects of dietary Se on productive and reproductive performance, tibial quality, and antioxidant capacity in laying duck breeders

This study evaluated the optimal concentrations of dietary Se for the productive and reproductive performance, tibial quality, and antioxidant status in duck breeders aged 23 to 49 wk. In total, 432 Longyan duck breeders aged 22 wk were allotted randomly to 6 treatments, each with 6 replicates of 12 individually caged birds. The experiment lasted for 27 wk, and birds were fed corn-soybean meal-based diets containing 0.11, 0.19, 0.27, 0.35, 0.43, or 0.51 mg Se/kg, respectively. The tested dietary Se levels did not affect egg production and tibial quality of duck breeders. The Se contents of the shell, yolk or albumin, whole egg, and the fertility of set eggs increased in a linear and quadratic manner (P < 0.05) in response to the increased dietary Se level, whereas the yolk malondialdehyde (MDA) and embryonic mortality decreased. The activities of glutathione peroxidase 3 (Gpx3) in plasma and Gpx1 in the erythrocytes and livers of breeder ducks increased in a linear and quadratic manner (P < 0.05) in response to increased dietary Se levels, whereas the total superoxide dismutase (T-SOD) activity increased and the MDA concentration decreased in the liver. The activity of Gpx3 in the plasma and Gpx1 in the erythrocytes and livers of newly hatched ducklings increased linearly (P < 0.01) with the increase in Se level, whereas the T-SOD activity and MDA concentration did not change. In conclusion, diets containing 0.27 mg Se/kg led to the highest egg fertility and hatchability in Longyan duck breeders, and using levels >0.19 mg Se/kg diet enhanced the antioxidant capacity in breeders and their offspring. The regression model indicated that dietary Se levels 0.19, 0.27, 0.28, 0.24, and 0.30 mg/kg are optimal levels to obtain maximum Se deposition efficiency in eggs, egg fertility, Gpx1 activity in erythrocytes and liver in duck breeders, and plasma activity of Gpx3 in newly hatched ducklings, respectively.

Beneficial antioxidant status of piglets from sows fed selenomethionine compared with piglets from sows fed sodium selenite

BACKGROUND

Studies in mammals proved dietary organic selenium (Se) being superior to inorganic Se regarding effects on growth performance, antioxidative status, immune response, and Se homeostasis. However, the picture of possible effects of different Se sources and - levels can be expanded. The present field study evaluated the effects on weight gain, hematological and selected biochemical variables as well as plasma concentrations of vitamin E (vitE), total Se and selenobiomolecules in piglets throughout the suckling period.

METHODS

Piglets were monitored from birth to 38 days of age (d). The mother sows' diets were enriched with l-selenomethionine (SeMet-0.26 and -0.43 mg Se/kg feed) or sodium selenite (NaSe-0.40 and -0.60 mg Se/kg feed) from 1 month prior to farrowing until the end of lactation period. Piglets received pelleted feed supplemented with Se similarly to the sows' diets from one week of age. Selenite at 0.40 mg Se/kg (NaSe-0.40) represents a common Se source and -level in pig feed and served as control diet.

RESULTS

From 24d, piglets in SeMet-groups had higher mean body weight (BW) compared with piglets from sows fed NaSe-0.40. Furthermore, from five-d and above, piglets from sows fed NaSe-0.60 had significantly higher BW than offspring from sows fed NaSe-0.40. Neonatal piglets in group SeMet-0.43 had significantly lower red blood cell counts (RBC), hemoglobin (Hgb) and hematocrit (Hct) concentrations compared with piglets from sows fed with NaSe-0.40. Neonatal and 5d-old piglets in group SeMet-0.26 showed higher gamma-glutamyl transferase activity than piglets in group NaSe-0.40. From five d and above, group NaSe-0.60 excelled with increased specific hematological variables culminating at age 38d with increased Hct, mean corpuscular volume (MCV), and MC hemoglobin (MCH) as well as increased activities of aspartate transaminase and lactate dehydrogenase compared with the other groups. Generally, offspring in the SeMet groups had higher total Se-concentrations in plasma than those from sows fed selenite, and showed a dose-response effect on plasma Se-concentrations. Furthermore, SeMet-fed piglets had higher plasma levels of the selenoproteins (Sel) glutathione peroxidase 3 (GPx3) and SelP as well as selenoalbumin. Plasma vitE levels were significantly negatively correlated with RBC throughout trial period.

CONCLUSIONS

Maternal supplementation with SeMet during gestation influenced hematology and clinical biochemistry in neonatal piglets in a different way than in offspring from sows receiving selenite enriched diets. Growth performance was positively influenced by both dietary Se source and Se level. Higher plasma levels of GPx3 observed in piglets receiving SeMet probably improved the protection against birth or growth related oxidative stress. These might prime the piglets for demanding situations as indicated by higher weight gain in offspring from sows fed with SeMet-supplemented diets. Our results on some enzyme activities might indicate that piglets fed NaSe-0.60 had to cope with increased levels of oxidative stress compared with those originating from sows fed SeMet or lower dietary levels of selenite. We assume that combining inorganic and organic Se sources in complete feed for breeding sows might be beneficial fro reproduction and the offspring's performance.

Impact of Maternal Selenium Supplementation from Late Gestation and Lactation on Piglet Immune Function

The present work aimed at assessing passive, innate, and acquired immunity in piglets from sows supplemented with either organic or inorganic selenium (Se). A total of 12 multiparous pregnant sows were randomly allocated to three groups: selenium-deficient, corn and soy-based diet base diet (BD), 0.3 mg Se/kg as hydroxy-selenomethionine (OH-SeMet), and 0.3 mg Se/kg as sodium selenite (SS). The feeding trial was carried out from gd 84 to weaning on postpartum day 21 (ppd 21). On gd 98 and 105, sows were vaccinated with hen egg white lysozyme (HEWL) to assess passive immunity. On ppd 23, weaned piglets were intramuscularly challenged with lipopolysaccharide (LPS) to trigger an acute-phase response. On ppd 14, 28, and 35, piglets were vaccinated with ovalbumin (OVA) to assess OVA-specific immunoglobulin G (IgG) and dermal hypersensitivity responses. Se levels in piglet plasma, muscle, and liver on ppd 21 were higher in OH-SeMet group. On ppd 2, piglet HEWL-specific IgG levels in OH-SeMet group were significantly increased. IL-10 and haptoglobin (HP) levels in OH-SeMet group were significantly increased 2 h and 48 h post-LPS simulation, respectively. The OVA-specific IgG levels in BD group were significantly higher than the other two groups, and the IL-4 concentration following whole blood ex vivo challenge with either OVA or mitogen was significantly increased in OH-SeMet group. OVA-specific skin swelling was lower in OH-SeMet and SS groups at 3 h and 6 h. This suggests that sow supplementation with OH-SeMet enhances mainly passive immunity through IgG maternal transfer and can influence piglet innate and acquired immunity.

Effect of feeding different sources of selenium on growth performance and antioxidant status of broilers

1. This study was conducted to determine the effect of different sources of selenium (Se) on breast and liver tissue deposition, apparent metabolisable energy (AME), growth performance and antioxidant status of broilers, measured as Se content in liver and breast tissues and glutathione peroxidase (GSH-Px) in blood, when used in 0-35 d broiler chicken diets. 2. A total of 200 male Ross 308 broilers were used in the feeding trial, which comprised two dietary phases, a starter from 0 to 21 d and finisher from 21 to 35 d of age. Four treatments with 10 replications each were used. A control diet (C) was formulated that was sufficient in protein and energy (230 and 215 g/kg of crude protein and 12.67 and 13.11 MJ/kg of metabolisable energy, respectively), for both phases, but contained background Se only from the feed ingredients. Diet 2 (IS) was supplemented with 10.35 g/t inorganic, elemental source of Se. Diet 3 (SY) was supplemented with 136.36 g/t selenised yeast, an organic source derived from Saccharomyces cerevisiae. Diet 4 (SS) was supplemented with 0.666 g/t sodium selenite, an inorganic source. 3. Birds fed the SY diet consumed less and weighed less than those fed IS or C (P < 0.05; 0-35 d of age), but there was no difference compared to birds fed SS diets. There were no differences in FCR or dietary AME between broilers fed different Se sources. All diets containing supplementary Se increased concentrations in the liver and breast muscle, and for GSH-Px levels in blood compared to birds fed the C diet (P < 0.001). Birds fed SY diets had greater Se levels in liver and breast tissues compared to birds fed any of the other diets (P < 0.001). 4. Diets supplemented with Se had variable effects on broiler growth performances and antioxidant status. Feeding Se from a yeast source has higher transfer into breast tissues. Feeding different sources and levels of Se to birds in a more challenging situation to induce oxidative stress may bring more conclusive results.

Utilization of guava extract as additive antioxidant in diets of Japanese quail breeders (Coturnix japonica)

SUMMARY The aim of this study was to evaluate the guava extract as an antioxidant additive in diets of Japanese quail breeders on the performance and egg’s quality. The experiment was conducted at University Federal of Goias. A total of 384 Japanese quail breeders were used, distributed in four treatments, with six replicates, with a total of 12 females and four males in each replicate. The treatments were performed with four levels of guava extract in the diets (0.0%, 0.3%, 0.6% and 0.9%). The guava extract contained the ellagic acid, considered the guava antioxidant active principle. The diets were isonutritive. Feed and water were offered ad libitum. The experimental period was 84 days. Egg production, feed intake, feed conversion ratio, egg mass, body weight variation and egg quality were evaluated. The results were submitted to analysis of variance and regression analysis. The adopted probability was 5%. Egg production, feed intake, feed conversion ratio and egg mass were not influenced by the use of guava extract. The yolk and albumen height, the Haugh Unit and the yolk and albumen index decreased linearly as the levels of guava extract in the diet increased. The diameter of the albumen was higher with the use of 0.48% of guava extract in the diet. The yolk color was affected by the guava extract, presenting a darker color with 0.50% of guava extract in the diet. It was concluded that the guava extract used as an antioxidant additive does not improve the performance and egg quality of Japanese quails.

Nutritional modulation of the antioxidant capacities in poultry: the case of selenium

Natural antioxidants play important roles in maintaining chicken health, productive and reproductive performance of breeders, layers, rearing birds, and growing broilers. There is a wide range of antioxidant molecules in the body: vitamin E, carotenoids, selenium, ascorbic acid, coenzyme Q, carnitine, taurine, antioxidant enzymes, etc. In the body all antioxidants work together to create the antioxidant network called "antioxidant systems" with Se being the "chief-executive." Analysis of the current data on selenium roles in antioxidant defenses in poultry clearly showed its modulatory effect at the level of breeders, developing embryos, newly hatched chicks, and postnatal chickens. On the one hand, Se is involved in the expression and synthesis of 25 selenoproteins, including GSH-Px, TrxR, and SepP. On the other hand, Se affects non-enzymatic (vitamin E, CoQ, and GSH) and enzymatic (SOD) antioxidant defense mechanisms helping build strong antioxidant defenses. Se efficiency depends on the level of supplementation and form of dietary Se, organic Se sources being more effective modulators of the antioxidant systems in poultry than sodium selenite. Moreover, Se levels in eggs from some wild avian species are close to those found in chicken eggs after 0.3 ppm organic Se supplementation and a search for most effective dietary form of organic Se is a priority in poultry nutrition. Antioxidant/prooxidant (redox) balance of the gut and the role/interactions of Se and microbiota in maintaining gut health would be a priority for future poultry research.

Dietary selenomethionine increases antioxidant capacity of geese by improving glutathione and thioredoxin systems

A total of 200 healthy 28-day-old male Jiangnan White geese were used to investigate the free radical scavenging ability, reduced glutathione (GSH) and thioredoxin systems, and the concentrations of reactive oxygen metabolites (ROM), malondialdehyde (MDA), and protein carbonyl (PC) in geese fed diets with organic selenium (Se) (Selenomethionine, SeMet) and inorganic Se (sodium selenite, SS). All geese were randomly allotted into 4 groups with 5 replicates of 10 geese each, and received basal diet supplemented with 0.3 mg Se/kg SS, 0.2, 0.3 and 0.4 mg Se/kg SeMet until 70 D of age, respectively. Geese in the SS and SeMet groups exhibited similar growth performance. Diet with SeMet increased the scavenging abilities of 2,2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt free radical (ABTS•+, P < 0.001) and superoxide radical (O2-•, P = 0.002) in the serum of geese, as well as the scavenging abilities of ABTS•+ (P = 0.023), hydroxyl radical (P = 0.009) and O2-• (P = 0.019) in the liver of geese. Compared to the SS group, SeMet increased hepatic GSH concentration (P = 0.002), the activities of glutathione peroxidase (P = 0.031), γ-glutamate cysteine ligase (P < 0.001), and thioredoxin reductase (P < 0.001), and decreased the concentrations of ROM, MDA, and PC in the serum and liver of geese (P < 0.05). In conclusion, dietary SeMet inclusion would be more effective than SS in increasing the antioxidant capacity of geese, possibly by improving GSH and thioredoxin systems, and 0.2 mg Se/kg SeMet in goose diet is recommended.

Selenium status in lactating mothers-infants and its potential protective role against the neurotoxicity of methylmercury, lead, manganese, and DDT

A total of 206 lactating mothers and their infants (3-12 months) were included in this study to evaluate postnatal exposure to neurotoxic pollutants such as methylmercury (MeHg), lead (Pb), manganese (Mn), dichlorodiphenyltrichloroethane (DDT) and its metabolites [dichlorodiphenyldichloroethane (DDD), and dichlorodiphenyldichloroethylene (DDE)] and their association with delayed neurological development and to explore the protective role of selenium (Se) against chemical neurotoxicity. Neurodevelopmental performance was evaluated using Denver Developmental Screening Test II and Parents' Evaluation of Developmental Status (PEDS). Multivariate log-binomial regression modeling was applied for both single and multiple exposures to chemicals using a principal component analysis that generated six principal components. Both mothers and their infants had been exposed to metals and DDT metabolites, with some exceeding the accepted permissible limits. The geometric means of MeHg, Pb, Mn, DDD, DDE and DDT levels in breast milk were 1.333, 45.327, 15.576, 0.069, 0.542 and 1.08 μg/l, respectively. A single-exposure model identified a high risk of reduced PEDS performance significantly associated with DDD in breast milk [relative risk (RR) = 1.484; 95% confidence interval (95%CI) = 1.091-2.019] and marginally significantly associated with Pb in the mothers' blood (RR = 2.164; 95%CI = 0.87-5.382). We did not find a protective role of Se in neurodevelopment due to its high levels in the mothers. Models of multi-chemical exposure indicated that Mn in blood and breast milk, Se in blood and Pb in the mothers' urine were marginally significantly associated with a high risk of reduced PEDS performance (RR = 0.424; 95%CI = 0.176-1.022). The use of multi-chemical exposure approach in early life risk assessments is important because it indicates real-world exposure. Our results were not conclusive because the sample size was small, so future studies examining the implications to health of the impact of prenatal/postnatal exposure to a mixture of chemicals in the Saudi population are merited.

Role of Selenium and Selenoproteins in Male Reproductive Function: A Review of Past and Present Evidences

Selenium (Se) is an important trace mineral having many essential roles at the cellular and organismal levels in animal and human health. The biological effects of Se are mainly carried out by selenoproteins (encoded by 25 genes in humans and 24 in mice). As an essential component of selenoproteins, Se performs structural and enzymic roles; in the latter context it is well known for its catalytic and antioxidative functions. Studies involving different animal models have added great value to our understanding regarding the potential implications of Se and selenoproteins in mammalian fertility and reproduction. In this review, we highlight the implications of selenoproteins in male fertility and reproduction followed by the characteristic biological functions of Se and selenoproteins associated with overall male reproductive function. It is evident from observations of past studies (both animal and human) that Se is essentially required for spermatogenesis and male fertility, presumably because of its vital role in modulation of antioxidant defense mechanisms and other essential biological pathways and redox sensitive transcription factors. However, bearing in mind the evidences from mainstream literature, it is also advisable to perform more studies focusing on the elucidation of additional roles played by the peculiar and canonical selenoproteins i.e., glutathione peroxidase 4 (GPX4) and selenoprotein P (SELENOP) in the male reproductive functions. Nevertheless, search for the elucidation of additional putative mechanisms potentially modulated by other biologically relevant selenoproteins should also be included in the scope of future studies. However, as for the implication of Se in fertility and reproduction in men, though a few clinical trials explore the effects of Se supplementation on male fertility, due to inconsistencies in the recruitment of subjects and heterogeneity of designs, the comparison of such studies is still complicated and less clear. Therefore, further research focused on the roles of Se and selenoproteins is awaited for validating the evidences at hand and outlining any therapeutic schemes intended for improving male fertility. As such, new dimensions could be added to the subject of male fertility and Se supplementation.

Biosynthesis of Polysaccharides-Capped Selenium Nanoparticles Using Lactococcus lactis NZ9000 and Their Antioxidant and Anti-inflammatory Activities

Lactococcus lactis (L. lactis) NZ9000, which has been genetically modified, is the most commonly used host strain for nisin regulated gene expression. Selenium (Se) is an essential trace element in the diet of humans and animals important for the maintenance of health and growth. Biosynthesized Se nanoparticles (SeNPs) that use microorganisms as a vehicle are uniquely advantages in terms of low costs, low toxicity and high bioavailability. This study was aimed at preparing novel functionalized SeNPs by L. lactis NZ9000 through eco-friendly and economic biotechnology methods. Moreover, its physicochemical characteristics, antioxidant and anti-inflammatory activities were investigated. L. lactis NZ9000 synthesized elemental red SeNPs when co-cultivated with sodium selenite under anaerobic conditions. Biosynthesized SeNPs by L. lactis NZ9000 were mainly capped with polysaccharides and significantly alleviated the increase of malondialdehyde (MDA) concentration, the decrease of glutathione peroxidase (GPx) and total superoxide dismutase (T-SOD) activity in porcine intestinal epithelial cells (IPEC-J2) challenged by hydrogen peroxide (H₂O₂). SeNPs also prevented the H₂O₂-caused reduction of transepithelial electrical resistance (TEER) and the increase of FITC-Dextran fluxes across IPEC-J2. Moreover, SeNPs attenuated the increase of reactive oxygen species (ROS), the reduction of adenosine triphosphate (ATP) and the mitochondrial membrane potential (MMP) and maintained intestinal epithelial permeability in IPEC-J2 cells exposed to H₂O₂. In addition, SeNPs pretreatment alleviated the cytotoxicity of Enterotoxigenic Escherichia coli (ETEC) K88 on IPEC-J2 cells and maintained the intestinal epithelial barrier integrity by up-regulating the expression of Occludin and Claudin-1 and modulating inflammatory cytokines. Biosynthesized SeNPs by L. lactis NZ9000 are a promising selenium supplement with antioxidant and anti-inflammatory activities.

Selenium-enriched probiotics improve hepatic protection by regulating pro-inflammatory cytokines and antioxidant capacity in broilers under heat stress conditions

Objective:

High ambient temperature in poultry is a challenging and fatal stress among environmental factors. It affects the production quality, damages the liver, and increases mortality in broilers. The present study is focused to explore appropriate utilization of Selenium (Se) as a feed additive in broiler chickens against high temperature.

Materials and Methods:

Day-old male broiler chickens (Ross 308) (n = 200) were grouped according to the supplements used in their basal diets such as: corn-soybean basal diet as control (Con), a basal diet containing sodium selenite, basal diet with probiotics, and a basal diet containing selenium-enriched probiotics (SP). At the end of the experimental period of 42 days, the liver was isolated and was used to determine the antioxidant capacity through a spectrophotometer. Inflammatory and anti-inflammatory cytokines production in the liver was measured through a real-time polymerase chain reaction.

Results:

Hepatic analyses revealed the decreased level of malondialdehyde, whereas glutathione, glutathione peroxidase (GSH-Px), and superoxide dismutase levels were increased in the SP group. Furthermore, supplementation of SP significantly up-regulated the mRNA expression of glutathione peroxidase 1 (GPx1), GPx4, IL6, and IL10 and down-regulated the expression of pro-inflammatory cytokines.

Conclusion:

It is thus concluded that SP as a potential nutritive supplement may facilitate hepatic protection by suppressing hepatic oxidation, inflammation, and necrosis during the high ambient temperature of summer.

Effects of nano-selenium on mRNA expression of markers for spermatogonial stem cells in the testis of broiler breeder males

Fertility is one of the most important parameters in breeder farms and cockerels play an outstanding role in the fertility of eggs in broiler breeder farms. Todays, supplementation of chicken diet with additives such as organic selenium is used to increase fertility. The aim of this study was to evaluate the effects of different levels of nano-selenium (Nano-Se) on the expression of molecular markers of spermatogonial stem cells (SSCs) in the testis of broiler breeder males. A total of 30 roosters of 40 weeks of age were randomly divided into five groups. Groups were as follows: 1) control (normal diet) group, 2) diet supplemented with 0.30 mg kg^-1 sodium selenite, 3) diet supplemented with 0.15 mg kg^-1 Nano-Se, 4) diet supplemented with 0.30 mg kg^-1 Nano-Se, and 5) diet supplemented with 0.60 mg kg^-1 Nano-Se. At the end of the experimental period (5^th week), birds were autopsied and samples from testis of all birds were collected. The testis samples were used to examine the β1-integrin (CD29), thy-1 (CD90) and NANOG mRNA expression by real-time PCR. The results showed that testis of the groups fed with the diets supplemented with 0.60 mg kg^-1 and 0.15 mg kg^-1 of Nano-Se had the highest and lowest mRNA expression of SSCs markers, respectively. In conclusion, the present study indicated that Nano-Se had advantages over sodium selenite. Diet supplemented with 0.60 mg kg^-1 of Nano-Se may contribute to optimal fertility via increasing the mRNA expression of SSCs markers of roosters’ testis and could be used to delay the reduction of fertility caused by aging in broiler breeder males.

Effects of Selenium and Cadmium on Breast Muscle Fatty-Acid Composition and Gene Expression of Liver Antioxidant Proteins in Broilers

The present work was part of a project intended to evaluate whether organic selenium (Se) has the potential to protect against toxic effects exerted by cadmium (Cd). For this reason, 300 as-hatched, one-day-old broiler chickens were randomly allocated in four dietary treatments with five replicate pens per treatment. Chickens in T1 treatment, were offered a diet supplemented with 0.3 ppm Se (as Se-yeast), without added Cd; in T2 treatment, they were offered a diet with 0.3 ppm Se and 10 ppm Cd; in T3 treatment, they were offered a diet with 0.3 ppm Se and 100 ppm Cd; in T4 treatment, chickens were offered a diet supplemented with 3 ppm Se and 100 ppm Cd. Cadmium was added to the diets in T2, T3, and T4 as CdCl₂. On the fourth and sixth weeks, liver and breast samples were obtained from two broilers per replicate pen. Relative gene expression levels of catalase (CAT), superoxide dismutase 1 (SOD1) and 2 (SOD2), methionine sulfoxide reductase A (MSRA) and B3 (MSRB3), iodothyronine deiodinase 1 (DIO1), 2 (DIO2), and 3 (DIO3), glutathione peroxidase 1 (GPX1) and 4 (GPX4), thioredoxin reductase 1 (TXNRD1) and 3 (TXNRD3), and metallothionein 3 (MT3) were analyzed by real-time quantitative PCR in liver, whereas the fatty-acid (FA) profile of breast muscle was determined by gas chromatography. Broilers supplemented with 0.3 ppm Se could tolerate low levels of Cd present in the diets, as there were no significant changes in the breast muscle FA profile, whereas excess Cd led to decreased polyunsaturated fatty acids (PUFAs), and in particular n-6 PUFA. Furthermore, treatments mainly affected the messenger RNA (mRNA) expression of SOD2, TXNRD3, and MT3, while age affected CAT, MSRB3, DIO2, DIO3, GPX4, TXNRD1, and MT3. In conclusion, dietary Se may help against the negative effects of Cd, but cannot be effective when Cd is present at excessive amounts in the diet.

Maternal Selenium and Developmental Programming

Selenium (Se) is an essential trace element of fundamental importance to health due to its antioxidant, anti-inflammatory, and chemopreventive properties, attributed to its presence within at least 25 selenoproteins (Sel). In this review, we describe some of the recent progress, in our understanding, on the impact of maternal Se intake during the periconceptional period on offspring development and health. Maternal nutrition affects the performance and health of the progeny, and both maternal and offspring Se supplementations are essential for the optimal health and antioxidant protection of the offspring. The case of Se in epigenetic programming and early life nutrition is also discussed.

Mineral supplementation: effects on bone integrity and intestinal morphometry of broiler chickens challenged with Eimeria sp

The objective of this study was to evaluate the effect of supplementation of organic minerals on the productive performance and bone quality of broilers from 1 to 21 days of age and the intestinal health in situations of enteric challenge from 21 to 28 days of age. In a completely randomized design, with two treatments composed for minerals as sulfate and Carbo-Amino-Phospho-Chelate (CAPC), a total of 900 male broiler chicks were allocated to nine replicates and 18 experimental units with 50 birds each. 640 birds at 21 days of age were transferred to experimental cages and distributed in a completely randomized design, in factorial 2 × 2 (minerals as sulfate and CAPC × with and without enteric challenge), obtaining 4 treatments with 16 replicates and 10 birds each. In the same day of change, the group of challenged broilers received a commercial vaccine for coccidiosis that covers the Eimeria sp. At 7 days, the supplementation with CAPC minerals resulted in higher (p<0.05) weight gain and better feed conversion in relation to the inorganic source. The deposition of minerals evaluated in the tibia of broilers was not influenced (p>0.05) by the source of minerals, with the exception of Cu and Mn, whose deposition was greater (p<0.05) in the bones of poultries supplemented with inorganic source of minerals. There was higher (p<0.05) length and width of the villi and increase in the ratio villus: crypt in response to the intestinal spoliation with CAPC supplementation when compared to the inorganic source.

Increasing selenium supply for heat-stressed or actively cooled sows improves piglet preweaning survival, colostrum and milk composition, as well as maternal selenium, antioxidant status and immunoglobulin transfer

This study aimed to evaluate the effects of increasing selenium (Se) supply for heat-stressed or actively cooled sows on sow productivity, colostrum and milk composition, as well as the selenium and antioxidant status and immunoglobulin levels of sows and nursing piglets. The study was a 2 × 2 factorial design, where the first factor was farrowing environment [heat stress vs. actively cooling, temperature: 29.61 ± 0.19 ℃ (27.70-31.60 ℃) vs. 27.90 ± 0.15 ℃ (26.90-30.20 ℃); temperature-humidity index: 72.91 ± 0.26 (70.30-75.70) vs. 70.81 ± 0.22 (69.30-73.80)], and the second factor was dietary Se level during late gestation and lactation [(0.3 vs. 1.2 mg/kg Se as Se-yeast, the basal diet was corn-soybean meal diet formulated according to NRC (2012) except for Se level]. Forty multiparous sows (Landrace × Yorkshire) were randomly allotted to 1 of 4 treatments (10 sows and following 90 piglets per treatment, respectively). The results show that: (1) There were no interactions of farrowing environment with Se treatments with the exceptions of nutrient content of 7-d milk; (2) As for zootechnical measures, piglets of sows receiving increasing Se tended to have greater preweaning survival compared with those of sows receiving control diet without interactions of environment and Se treatments; (3) As to colostrum and milk composition, greater concentrations of protein, lactose, solids-not-fat in colostrum, and greater fat concentration in 7-d and 14-d milk were found for sows fed increasing Se; (4) Regarding Se and antioxidant status, increasing Se supply for sows increased Se content in colostrum and 21-d milk, as well as in plasma of 1-day-old and 21-day-old piglets. Meanwhile, increasing Se supply for sows improved antioxidant status in colostrum (MDA content) and 21-d milk (T-AOC and MDA content), as well as in plasma of 1-day-old and 21-day-old piglets (GSH-Px activity and MDA content); (5) With regard to immunoglobulins, sows fed increasing Se had higher IgM levels in colostrum, and higher IgA in 21-d milk. Also, piglets from sows fed increasing Se had higher plasma IgA at 1 d of age, and higher IgA and IgG levels at 21 d of age. Collectively, increasing selenium supply for heat-stressed or actively cooled sows improved piglet preweaning survival, colostrum and milk composition, as well as maternal selenium, antioxidant status and immunoglobulin transfer irrespective of the climatic conditions, which indicates that Se requirements for sows should be urgently reassessed.

Selenium Deficiency Affects Immune Function by Influencing Selenoprotein and Cytokine Expression in Chicken Spleen

Se is an important bioelement essential for a healthy immune system. Dietary Se influences both innate and adaptive immune responses. However, the effects of Se deficiency in chicken spleen are still unknown; thus, we designed an experiment to study the role of Se in chicken spleen. A total of 180 one-day-old sea blue white laying hens were randomly allocated into two groups (a control group and a Se-deficient group). The control group was fed a diet supplemented with sodium selenite with a final Se content of 0.15 mg/kg, and the Se-deficient group was fed a Se-deficient diet with a Se content of 0.033 mg/kg. Twenty selenoproteins and ten cytokines were investigated in detail. The expression levels of selenoproteins in spleen were determined via real-time qPCR at 15, 35, and 55 days, and cytokine levels were determined using ELISA at 15, 35, and 55 days. Protein-protein interaction predictions and principal component analysis were performed. We found that the selenoprotein mRNA levels were significantly lower (P < 0.05) in the Se-deficient group compared with the control group. The expression levels of IL-2, IL-1β, IL-6, IFN-α, and IL-17 were significantly lower (P < 0.05), and the levels of IL-8, IL-10, IFN-γ, IFN-β, and TNF-α were significantly higher (P < 0.05) in the Se-deficient group. These selenoproteins were positively correlated with component 1 and component 2 of the PCA, but the relationship between cytokines and principal components in spleens was very complex. The investigation showed that Se deficiency caused a reduction in selenoprotein gene expression and further affected certain cytokines levels. Our results provide some compensatory data about selenoproteins and cytokines in spleens of Se-deficient chickens and provide clues for further research on the relationship between selenoproteins and cytokines.

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.

Selenium, Selenoproteins, and Female Reproduction: A Review

Selenium (Se) is an essential micronutrient that has several important functions in animal and human health. The biological functions of Se are carried out by selenoproteins (encoded by twenty-five genes in human and twenty-four in mice), which are reportedly present in all three domains of life. As a component of selenoproteins, Se has structural and enzymatic functions; in the latter context it is best recognized for its catalytic and antioxidant activities. In this review, we highlight the biological functions of Se and selenoproteins followed by an elaborated review of the relationship between Se and female reproductive function. Data pertaining to Se status and female fertility and reproduction are sparse, with most such studies focusing on the role of Se in pregnancy. Only recently has some light been shed on its potential role in ovarian physiology. The exact underlying molecular and biochemical mechanisms through which Se or selenoproteins modulate female reproduction are largely unknown; their role in human pregnancy and related complications is not yet sufficiently understood. Properly powered, randomized, controlled trials (intervention vs. control) in populations of relatively low Se status will be essential to clarify their role. In the meantime, studies elucidating the potential effect of Se supplementation and selenoproteins (i.e., GPX1, SELENOP, and SELENOS) in ovarian function and overall female reproductive efficiency would be of great value.

Maternal Selenium Supplementation Enhanced Skeletal Muscle Development Through Increasing Protein Synthesis and SelW mRNA Levels of their Offspring

The present study aimed to investigate the influence of maternal selenium supplementation on the skeletal muscle development of the offspring. A total of 720 Ross 308 broiler breeders at 24-week-old were allocated into 3 treatments with 6 replicates of 40 hens each and fed with 0 mg/kg-(group Se/C), 0.5 mg/kg organic-(group Se/O), and 0.5 mg/kg inorganic-(group Se/I) selenium, respectively for 8 weeks. The male offspring from each nutritional treatment were divided and housed into 8 cages of 12 birds each and fed with a commercial diet supplemented with selenium from Na₂SeO₃ at 0.15 mg/kg. Results showed that Se/O group had the highest selenium deposition (P < 0.05) in the egg yolk and albumen. Furthermore, maternal selenium supplementation promoted breast muscle yield; increased serum insulin and IGF-I concentration; upregulated AKT, mammalian target of rapamycin (mTOR), P70S6K, Myf5, MyoD, MyoG, and SelW mRNA levels; and improved the phosphorylation of AKT at Serine 473 residue, mTOR at Serine 2448 residue, and FOXO at Serine 256 residue in skeletal muscles of the offspring. In contrast, the hens' diet supplemented with selenium could result in reduction of uric acid level in serum and downregulation of Atrogin-1 and MuRF1 mRNA levels in the skeletal muscle of the offspring. Additionally, no significant effect on the skeletal muscle development post-hatch was observed between organic and inorganic selenium supplementation. In conclusion, maternal organic selenium supplementation improved selenium deposition in egg; however, no significant effect has been detected on the breast muscle development of the offspring of broiler breeder compared with inorganic selenium supplementation.

Cytosolic Distribution of Metals (Cd, Cu) and Metalloids (As, Se) in Livers and Gonads of Field-Collected Fish Exposed to an Environmental Contamination Gradient: An SEC-ICP-MS Analysis

The distribution of As, Cd, Cu and Se among biomolecules of different molecular weight (MW) in the heat-treated cytosolic fraction of livers and gonads of white suckers (WS; Catostomus commersonii) collected in a reference lake and in a lake subject to multi-metal contamination was investigated. Distribution profiles were obtained by separation of the heat-stable protein and peptide (HSP) fractions using size-exclusion high performance-liquid chromatography, coupled online to an inductively coupled plasma mass spectrometer, to quantify the associated metals. Metal-handling strategies did not vary between the reference and exposed fish, with the exception of As. Cadmium and Cu appeared associated with the heat-stable peptides metallothioneins (MTs), indicating their reasonable detoxification and regulation in WS. In contrast, Se and As were not bound to MTs, but rather, to biomolecules of lower MW (<2 kDa). Arsenic was found associated with the same biomolecules in fish from both lakes, but their proportions changed between reference and exposed fish. For future work, the identification of the Se and As binding biomolecules would be of great interest to determine if these metalloids are detoxified or if, conversely, the biomolecules are metal-sensitive and their binding to Se or As represents a threat for the health of these fish.

Subcellular partitioning of metals and metalloids (As, Cd, Cu, Se and Zn) in liver and gonads of wild white suckers (Catostomus commersonii) collected downstream from a mining operation

In the present study, we examined the subcellular distribution of metals and metalloids (As, Cd, Cu, Se and Zn) in the liver and gonads of wild white suckers (Catostomus commersonii) collected downstream from a metal mining operation (exposure area) and in a reference area. Metal partitioning among potentially metal-sensitive fractions (heat-denatured proteins (HDP), mitochondria and microsomes) and potentially biologically detoxified fractions (heat-stable proteins (HSP) and metal-rich granules) within cells was determined after differential centrifugation, NaOH digestion and heat-denaturation steps. Metal-handling strategies between liver and gonads, and between sexes, were examined. Hepatic metal concentrations were significantly higher in exposed compared to reference fish, especially for Se (14x), Cd (5x) and Cu (3x), and did not vary between sexes. In contrast, gonadal Cd, Cu, Se and Zn concentrations were consistently lower in testes than in ovaries; marked differences in Cd and Se concentrations between exposed and reference fish were observed for both sexes. Overall, metal-handling strategies were similar in both liver (male and female pooled) and female gonads, but differed from those in male gonads, likely due to the different functions assigned to ovaries and testes. Subcellular partitioning of As, Cd and Cu showed that the HSP fraction was most responsive to increased metal exposure, presumably reflecting Cu regulation, and possibly Cd and As detoxification. Zinc concentrations were tightly controlled and mainly found in the HDP fraction. Interestingly, changes in Cd-handling strategy in female gonads were particularly evident, with Cd shifting dramatically from the metal-sensitive HDP fraction in reference fish to the metal-detoxified HSP fraction in exposed fish. It seems that Cd detoxification in female gonads was not fully induced in the less contaminated fish, but became more effective above a threshold Cd concentration of 0.05 nmol/g dry weight. Partitioning of Se was different, with the largest contributor to the total liver and gonad Se burdens being the putative metal-sensitive HDP fraction, suggesting that excess Se in this fraction in exposed fish may lead to Se-related stress. The present subcellular partitioning results demonstrate that metal handling strategies vary among metals, between organs and (in some cases) as a function of metal exposure. They also show promise in identifying metals of potential concern in a risk assessment context.

Damage to the myogenic differentiation of C2C12 cells by heat stress is associated with up-regulation of several selenoproteins

This study was conducted to profile the selenoprotein encoding genes or proteins in mouse C2C12 cells and integrate their roles in the skeletal cell damage induced by heat stress (HS). Cells were cultured at 37.0 °C or 41.5 °C for 4, 6 or 8 days. The mRNA expression of 24 selenoprotein encoding genes and abundance of 5 selenoproteins were investigated. HS suppressed myogenic differentiation and impaired the development of muscle myotubes. HS down-regulated (P < 0.01) mRNA abundance of MYOD and MYOGENIN, and decreased (P < 0.01) MYOGENIN protein expression, HS elevated (P < 0.01) HSP70 and (P < 0.01) the ratio of BCL-2 to BAX at both mRNA and protein level. Meanwhile, HS up-regulated (P < 0.01–0.05) expressions of 18, 11 and 8 selenoprotein encoding genes after 4, 6 and 8 days of hyperthermia, and only down-regulated (P < 0.01) DIO2 after 6 and 8 days of hyperthermia, respectively. Furthermore, HS influenced expression of selenoproteins and up-regulated (P < 0.01–0.05) GPX1, GPX4 and SEPN1 after 6 days of HS. The damage to development of mouse skeletal muscle myotubes by HS accompanied with the up-regulation of both selenoprotein encoding genes and proteins, which suggested a potential protective effect of selenoprotein on hyperthermia associated damage in C2C12 cells.

Selenium-Dependent Antioxidant Enzymes: Actions and Properties of Selenoproteins

Unlike other essential trace elements that interact with proteins in the form of cofactors, selenium (Se) becomes co-translationally incorporated into the polypeptide chain as part of 21st naturally occurring amino acid, selenocysteine (Sec), encoded by the UGA codon. Any protein that includes Sec in its polypeptide chain is defined as selenoprotein. Members of the selenoproteins family exert various functions and their synthesis depends on specific cofactors and on dietary Se. The Se intake in productive animals such as chickens affect nutrient utilization, production performances, antioxidative status and responses of the immune system. Although several functions of selenoproteins are unknown, many disorders are related to alterations in selenoprotein expression or activity. Selenium insufficiency and polymorphisms or mutations in selenoproteins' genes and synthesis cofactors are involved in the pathophysiology of many diseases, including cardiovascular disorders, immune dysfunctions, cancer, muscle and bone disorders, endocrine functions and neurological disorders. Finally, heavy metal poisoning decreases mRNA levels of selenoproteins and increases mRNA levels of inflammatory factors, underlying the antagonistic effect of Se. This review is an update on Se dependent antioxidant enzymes, presenting the current state of the art and is focusing on results obtained mainly in chicken.

Lower Selenoprotein T Expression and Immune Response in the Immune Organs of Broilers with Exudative Diathesis Due to Selenium Deficiency

The objective of the present study was to investigate whether dietary selenium (Se) deficiency would affect the expression of selenoprotein T (SelT) and immune response in the immune organs of broilers. Changes in expression of inflammatory cytokines and oxidative stress response caused by Se deficiency can lead to organism damage, which in turn leads to immune response. Sixty (1-day-old) broilers were divided into the control group and Se-deficiency group. Animal models with exudative diathesis were duplicated in the broilers by feeding them Se-deficient diet for 20 days. After the Se-deficient group exhibited symptoms of exudative diathesis, all the broilers were euthanized, and their immune organs were taken for analysis. The tissues including spleen, bursa of Fabricius, and thymus were treated to determine the pathological changes (including microscopic and ultramicroscopic), the messenger RNA (mRNA) expression levels of SelT and its synthetase (SecS and SPS1), cytokine mRNA expression levels, and antioxidant status. The microscopic and ultramicroscopic analyses showed that immune tissues were obviously injured in the Se-deficient group. The mRNA expression of SelT was decreased compared with that in the control group. Meanwhile, the mRNA expression levels of SecS and SPS1 were downregulated. In the Se-deficient group, the mRNA expression levels of IL-1R and IL-1β were higher than those of three control organs. Additionally, the IL-2 and INF-γ mRNA expression levels were lower than those of the control group. The activity of CAT was decreased, and the contents of H₂O₂ and •OH were increased due to Se deficiency. Pearson method analysis showed that the expression of SelT had a positive correlation with IL-2, INF-γ, SecS, and SPS1 and a negative correlation with IL-1R and IL-1β. In summary, these data indicated that Se-deficient diet decreased the SelT expression and its regulation of oxidative stress, and it inhibited a pleiotropic mechanism of the immune response.