The Influence of Supplements of Selenite,Selenate and Selenium Yeast on the Selenium Status of Dairy Heifers

The aim of the study was to define possible differences between selenite, selenate and selenium yeast on various aspects of selenium status in growing cattle. Twenty-four Swedish Red and White dairy heifers were fed no supplementary selenium for 6 months. The basic diet contained 0.026 mg selenium/kg feed dry matter (DM). After the depletion period the animals were divided into 4 groups; group I–III received 2 mg additional selenium daily as sodium selenite, sodium selenate, and a selenium yeast product, respectively. Group IV, the control group, received no additional selenium. The total dietary selenium content for groups I–III during the supplementation period was 0.25 mg/kg DM. After the depletion period the mean concentration of selenium in blood (640 nmol/l) and plasma (299 nmol/l) and the activity of GSH-Px in erythrocytes (610 µkat/l) were marginal, but after 3 months of supplementation they were adequate in all 3 groups. The concentration of selenium in blood and plasma was significantly higher in group III than in groups I and II, but there was no significant difference between groups I and II. The activity of GSH-Px in erythrocytes did not differ between any of the supplemented groups. The animals in the control group had significantly lower concentrations of selenium in blood and plasma and lower activities of GSH-Px in erythrocytes than those in the supplemented groups. The activity of GSH-Px in platelets was also increased by the increased selenium intake. There was no difference in the concentration of triiodothyronine (T3) between any of the groups, but the concentration of thyroxine (T4) was significantly higher in the unsupplemented control group.     

Effect of Pineal Proteins at Different Dose Level on Fluoride-Induced Changes in Plasma Biochemicals and Blood Antioxidants Enzymes in Rats

Pineal glands secrets melatonin and various proteins and peptides which has many physiological functions. In keeping with this view, present experiment was conducted to know the effect of buffalo (Bubalus bubalis) pineal proteins (PP) at different dose level on fluoride-induced changes in plasma biochemicals and blood antioxidants enzymes in female rats. For this, we took 30 adult female Wistar rats (133–145 g body weights, BW) and divided into five groups (control, group I; 150 ppm fluoride (F), group II; F+ 50 µg pineal proteins, group III; F+ 100 µg PP, group IV; F+ 200 µg PP, group V). We administered fluoride (150 ppm, drinking water) and F+ pineal proteins at 50, 100, and 200 µg/kg BW, i.p. daily for 21 days. Blood samples were collected at the end of the experiments to estimate plasma glucose, proteins, F, lipid peroxidation (LPO), alkaline phosphatase (ALP), and acetyl cholinesterase (AChE) activity. Red blood cells (RBCs) were separated for analysis of LPO, AChE, catalase (CAT), superoxide dismutase (SOD), reduced glutathione (GSH), glutathione peroxidase (GPx), and glutathione reductase (GR) in different groups of animals. Total plasma glucose and protein level did not significantly change in F-treated rats. Plasma ALP and F level were significantly (p?<?0.05) high in group II as compared with control and groups III, IV, and V. Administration of PP at different dose level significantly (p?<?0.05) reduced the F concentration and ALP activity. Plasma and RBCs AChE activity was significantly (p?<?0.05) reduced in F-treated animals as compared with control rats and significantly (p?<?0.05) elevated on exogenous administration of PP (groups III and IV). Plasma and RBCs LPO level was significantly (p?<?0.05) high in F-alone-treated rats, and PP caused significant (p?<?0.05) reduction of LPO in groups IV and V. However, PP treatment in group IV brought better amelioration of F-induced high LPO than in groups III and V. At no dose level, PP-ameliorated F-induced depression of RBCs GSH, CAT, GR, and GPx level. Interestingly, SOD activity was elevated in dose-dependent manner at different dose level of PP in groups III, IV, and V than control and F-administered rats. These findings clearly indicate the beneficial effects of buffalo pineal proteins on fluoride-induced adverse changes in certain plasma biochemical and blood antioxidant systems of rats. It further indicates that PP has dose-dependent ameliorative function against F-induced adverse effects in plasma and blood.     

Comparison of glutathione peroxidase 1 and iodothyronine deiodinase 1 mRNA expression in murine liver after feeding selenite or selenized yeast

The experiment was conducted to compare the effect of different selenium sources on the expression of glutathione peroxidase 1 (GPx1) and iodothyronine deiodinase 1 (Dio1) mRNA in mice by quantitative real-time PCR. A total of 60 male Kunming mice at average body weight of 20 g were allotted to three groups in a randomized complete block design, namely two treatments and one control. Mice in Group 1 were fed a basal diet as control, while mice in Groups 2 and 3 were fed the basal diet supplemented with 0.1 mg/kg selenium as sodium selenite or selenized yeast, respectively. Whole feeding experiment lasted for 30 d. At the end of the feeding trial, liver mRNA levels of GPx1 and Dio1 were determined by quantitative real-time PCR, as well as growth performance, body composition, blood and GPx activity were determined. The results showed that no significant differences in overall growth performance and body composition, including body weight, body length, heart weight, kidney weight and liver weight, were found between the experimental groups (P>0.05). Blood GPx activity increased in all of the selenium supplemented groups compared with control group (P<0.01). However, blood GPx activity in selenized yeast group was higher than that in sodium selenite group (P<0.05). Liver mRNA levels of GPx1 and Dio1 also increased in the two selenium supplemented groups compared with the control group (P<0.05), while there was no significant difference between the sodium selenite and selenized yeast groups (P>0.05). In conclusion, selenium increased the mRNA expression of GPx1 and Dio1 genes in murine liver, and there was no significant difference between the organic or inorganic form of selenium used.     

Vitex negundo Modulates Selenite-Induced Opacification and Cataractogensis in Rat Pups

Recently, much interest has been generated in the search for phytochemical therapeutics, as they are largely free from adverse side effects and economical. The goal of this study was to determine the efficacy of Vitex negundo in modulating the selenite-induced oxidative stress in vivo model. Sprague–Dawley rat pups of 8 days old were used for the study and divided into control (G I), selenite induced (G II), and selenite + V. negundo treated (G III). Cataract was induced by the single subcutaneous injection of sodium selenite (4 mg/kg body weight) on the tenth day and V. negundo (2.5 mg/Kg body weight) administered intraperitoneally from eighth to 15th day. Morphological examination of the rat lenses revealed no opacification in G I and mild opacification in G III whereas dense opacification in G II (stages 4–6). Levels of selenium in G II and G III showed no significant changes. The activities of superoxide dismutase, catalase, and Ca²⁺ATPase were significantly increased in G III compared to G II (p?<?0.05), while lower level of reactive oxygen species, Ca²⁺, and thiobarbituric acid reactive substances were observed in G III compared G II (p?<?0.05). These results indicate the therapeutic potential of methanolic extract of V. negundo on modulating biochemical parameters against selenite-induced cataract, which have been reported in this paper for the first time.     

Parameters of dietary selenium and vitamin E deficiency in growing rabbits.

4 x 5 growing female rabbits (New Zealand White) with an initial live weight of 610 +/- 62 g were fed a torula yeast based semisynthetic diet low in selenium (<0.03 mg/kg diet) and containing <2 mg alpha-tocopherol per kg (group I). Group II received a vitamin E supplementation of 150 mg alpha-tocopherylacetate per kg diet, whereas for group III 0.40 mg Se as Na-selenite and for group IV both supplements were added. Selenium status and parameters of tissue damage were analyzed after 10 weeks on experiment (live weight 2,355 +/- 145 g). Selenium depletion of the Se deficient rabbits (groups I and II) was indicated by a significantly lower plasma Se content (group I: 38.3 +/- 6.23 microg Se/mL plasma, group II: 42.6 +/- 9.77, group III: 149 +/- 33.4, group IV: 126 +/- 6.45) and a significantly lower liver Se content (group I: 89.4 +/- 18.2 microg/kg fresh matter, group II: 111 +/- 26.2) as compared to the Se supplemented groups III (983 +/- 204) and IV (926 +/- 73.9). After 5 weeks on the experimental diets differences in the development of plasma glutathione peroxidase were observed. As compared to the initial status group (45.2 +/- 4.50) pGPx activity in mU/mg protein was decreased in group I (19.1 +/- 7.08), remained almost stable in the vitamin E supplemented group II (46.3 +/- 11.2) whereas an elevated enzyme activity was measured in the Se supplemented groups III (62.4 +/- 23.9) and IV (106 +/- 19.9). In the rabbit organs investigated 10 weeks of Se deficiency caused a significant loss of Se dependent cellular glutathione peroxidase activity (GPx1) of 94% (liver), 80% (kidney), 50% (heart muscle) and 60% (musculus longissimus dorsi) in comparison to Se supplemented control animals. Damage of cellular lipids and proteins in the liver was due to either Se or vitamin E deficiency. However damage was most severe under conditions of a combined Se and vitamin E deficiency. It can be concluded that the activity of plasma glutathione peroxidase is a sensitive indicator of Se deficiency in rabbits. The loss of GPx1 activity indicates the selenium depletion in various rabbit organs. Both selenium and vitamin E are essential and highly efficient antioxidants which protect rabbits against lipid and protein oxidation.     

Production of Selenium-Enriched Biomass by Enterococcus durans

Selenium (Se) is an essential micronutrient for several organisms, and there is an increased interest about adequate sources for dietary selenium supplementation. The aim of this study was to evaluate the selenium bioaccumulation capacity of an Enterococcus strain. The isolate LAB18s was identified as Enterococcus durans by the VITEK® 2 system and analysis of both 16S rDNA gene sequence (JX503528) and the 16S-23S rDNA intergenic spacer (ITS). After 24-h incubation, E. durans LAB18s bioaccumulated elevated Se(IV) concentrations, reaching 2.60 and 176.97 mg/g in media containing initial amounts of 15 and 240 mg/l sodium selenite, respectively. The isolate grew optimally and had high selenium bioaccumulation at initial pH of 7.0 and 30 °C. Time course studies showed that E. durans LAB18s displayed the highest bioaccumulation of Se(IV) after 6 h of incubation. Analyses from scanning electron microscopy (SEM) demonstrated the presence of filaments connecting the cells of E. durans LAB18s cultivated in the presence of sodium selenite. It was demonstrated that a considerable amount of Se(IV) was absorbed by E. durans LAB18s. Therefore, this strain may represent an alternative source of organic dietary selenium.     

Selenium and Topiramate Attenuates Blood Oxidative Toxicity in Patients with Epilepsy: A Clinical Pilot Study

It is well known that oxidative stress plays an important role in the etiology of epilepsy. We investigated effects of selenium (Se) and topiramate (TPM) combination supplementation on antioxidant and oxidant values in control and patients with epilepsy and refractory epilepsy. For the aim, we used control (n?=?19), epilepsy + TPM (n?=?19), epilepsy + TPM + Se (n?=?15) groups. We also used control (n?=?15), refractory epilepsy (n?=?15), and refractory epilepsy + Se (n?=?8) groups. TPM (0.2 mg/daily) and Se, as sodium selenite (twice daily with 0.1 mg doses), were orally supplemented to the patients for 45 days. Erythrocyte lipid peroxidation levels were higher in refractory epilepsy groups than in control although its level and seizure numbers were decreased in TPM and TPM + Se supplemented groups of the patients. The erythrocyte reduced glutathione (GSH), glutathione peroxidase (GSH-Px), plasma total antioxidant status (TAS), and vitamin E concentration in refractory epilepsy group were lower than in control. However, the erythrocyte and plasma TAS, erythrocyte GSH and GSH-Px, and plasma vitamins A and C values were increased either by Se or Se + TPM in epilepsy and refractory epilepsy groups. There were no effects of TPM and Se on plasma β-carotene values in the groups. In conclusion, TPM and selenium caused protective effects on the epilepsy and refractory epilepsy-induced oxidative injury by inhibiting free radical production and supporting antioxidant redox system.     

The Impact of Magnesium on Isometric Twitch Parameters and Resting Membrane Potential of the Skeletal Muscle in Diabetic Rats

To present the relationship between oral magnesium supplementation, blood glucose, and changes in isometric twitch parameters, resting membrane potential (RMP), in the gastrocnemius muscle in diabetic rats. Sixty rats were used in this study. The rats were divided into four groups: control (drinking tap water, Group I, n = 15), control with treated with magnesium sulfate (10 g/L) (Group II, n = 15), diabetic (Group III, n = 15), and diabetic with treated with magnesium sulfate (10 g/L) (Group IV, n = 15). In Group II and IV, the level of plasma magnesium was increased comparing to those of the control group (p < 0.05). Isometric twitch tensions were decreased significantly in the Group III, but Group IV isometric twitch tensions were increased significantly. Group IV RMP values were close to the Group I. Hyperglycemia decreases gastrocnemius muscle isometric twitch tension and increases RMP in diabetic rats. Magnesium treatment can prevent these diabetic complications.     

Sodium selenite enhances glutathione peroxidase activity and DNA strand breaks in hepatoma induced by N-nitrosodiethylamine and promoted by phenobarbital

An element/compound that acts as an antioxidant as well as, can increase the oxidative stress offers a new approach in differentiation therapy. Experiments were carried out to determine the effect of selenite on DNA damage and glutathione peroxidase (GPx) activity in N-nitrosodiethylamine (DEN) induced, phenobarbital promoted rat hepatoma. Supra-nutritional level of selenite (4 ppm) was supplemented at either, before-initiation/after-initiation and/or during entire period of the study. At the end of experiment period (20 weeks), extent of DNA damage (alkaline comet assay), selenium concentration, and GPx activity were assessed on nodular tissue (NL) cells, surrounding liver (SL) cells, and whole liver tissue (control) cells. Hepatic selenium level and GPx activity were decreased in DEN and PB-administered animals, whereas the DNA damage was found to be increased in both NL and SL cells compared with control group. However, the DNA damage is more in SL cells than in NL cells. Pre-supplementation of selenite did not show any difference in DNA (strand breaks) damage, selenium, and GPx activity. Increased hepatic selenium concentration and GPx activity were observed in both NL and SL cells in post-supplementation and entire period of selenite supplemented animals compared to DEN + PB treated animals. However, DNA damage was increased in NL but decreased in SL cells. Supplementation of selenite alone for 16 or 20 weeks had shown increased DNA damage, selenium concentration, and GPx activity compared to normal control animals. In summary, cancer bearing animals increased DNA damage and decreased Se level and GPx activity in NL and SL cells and other organs in cancer bearing animals, supplementation of Se further provoked DNA damage (no change in pretreatment) in NL cells, however it decreased DNA damage SL cells and other organs (kidney, lungs, and spleen). On the other hand Se levels and GPx activity were increased in NL and SL cells and other organs of Se-supplemented rats (no difference in group 3 animals). These results demonstrate that, in addition to chemopreventive and chemotherapeutic role of selenite, it also prevents cellular DNA damage induced in cancerous condition.     

Effect of Organic Selenium Supplementation on Growth, Se Uptake, and Nutrient Utilization in Guinea Pigs

Forty weaned male guinea pigs (Cavia porcellus) of 152.6?±?7.96 g mean body weight were divided into four equal groups and fed a common basal diet comprised of 25% ground cowpea (Vigna unguiculata) hay, 30% ground maize (Zea mays) grain, 22% ground gram (Cicer arietinum) grain, 9.5% deoiled rice (Oryza sativa) bran, 6% soybean (Glycine max) meal, 6% fish meal, 1.5% mineral mixture (without Se), and ascorbic acid at 200 mg/kg to meet their nutrient requirements along with 0, 0.1, 0.2, and 0.3 ppm of organic selenium (Se) in groups I, II, III, and IV, respectively. Experimental feeding lasted for a period of 10 weeks, during which, daily feed intake and weekly body weights were recorded. Intake and digestibility of dry matter, organic matter, ether extract, crude fiber, and nitrogen-free extract as well as uptake of calcium and phosphorus were similar (P?>?0.05) among the four groups. Feed:gain ratio was also similar (P?>?0.05) in the four groups. However, digestibility of crude protein was significantly (P?<?0.001) higher in group II supplemented with 0.1 ppm organic Se as compared to other three group. Intake and absorption of Se was significantly (P?<?0.001) higher in all the Se supplemented groups as compared to control group. Average daily gain (ADG) was significantly (P?<?0.05) higher in group II (3.16 g/day) and III (3.38 g/day) as compared to group I (2.88 g/day). However, ADG in group IV (supplemented 0.3 ppm organic Se) was significantly (P?<?0.05) lower (2.83 g/day) than group II and III, but comparable (P?>?0.05) to group I. Findings of the present experiment suggests that Se requirements of guinea pigs are ≥0.2 ppm, as supplementation of 0.1 ppm organic Se in the diet (having 0.1 ppm Se) not only enhanced their growth rate but also improved the protein utilization.     

Protection of Selenium on Hepatic Mitochondrial Respiratory Control Ratio and Respiratory Chain Complex Activities in Ducklings Intoxicated with Aflatoxin B<Subscript>1</Subscript>

To investigate the protection of selenium on hepatic mitochondrial functions, 90 7-day-old ducklings were randomly divided into three groups (groups I–III). Group I was used as a blank control. Group II was administered with aflatoxin B₁ (0.1 mg/kg body weight). Group III was administered with aflatoxin B₁ (0.1 mg/kg body weight) plus selenium (sodium selenite, 1 mg/kg body weight). All treatments were given once daily for 21 days. The results showed that the activities of hepatic mitochondrial complexes I–IV in group II ducklings significantly decreased when compared with group I (P < 0.01). Furthermore, the activities of hepatic mitochondrial complexes I–IV in group III significantly increased when compared with group II (P < 0.05). The hepatic mitochondrial respiratory control ratio (RCR) in group II ducklings significantly decreased when compared with group I (P < 0.01). In addition, the hepatic mitochondrial RCR in group III significantly increased when compared with group II (P < 0.05). These results revealed that the aflatoxin B₁ significantly induced hepatic mitochondrial dysfunction in the activities of hepatic mitochondrial respiratory chain complexes I–IV and the RCR in ducklings. However, sodium selenite could significantly ameliorate the negative effect induced by aflatoxin B₁.     

Effects of selenium oxyanions on the white-rot fungus <Emphasis Type="Italic">Phanerochaete chrysosporium</Emphasis>

The ability of Phanerochaete chrysosporium to reduce the oxidized forms of selenium, selenate and selenite, and their effects on the growth, substrate consumption rate, and pellet morphology of the fungus were assessed. The effect of different operational parameters (pH, glucose, and selenium concentration) on the response of P. chrysosporium to selenium oxyanions was explored as well. This fungal species showed a high sensitivity to selenium, particularly selenite, which inhibited the fungal growth and substrate consumption when supplied at 10 mg L^?1 in the growth medium, whereas selenate did not have such a strong influence on the fungus. Biological removal of selenite was achieved under semi-acidic conditions (pH 4.5) with about 40 % removal efficiency, whereas less than 10 % selenium removal was achieved for incubations with selenate. P. chrysosporium was found to be a selenium-reducing organism, capable of synthesizing elemental selenium from selenite but not from selenate. Analysis with transmission electron microscopy, electron energy loss spectroscopy, and a 3D reconstruction showed that elemental selenium was produced intracellularly as nanoparticles in the range of 30–400 nm. Furthermore, selenite influenced the pellet morphology of P. chrysosporium by reducing the size of the fungal pellets and inducing their compaction and smoothness.     

Selenium uptake in Zea mays supplied with selenate or selenite under hydroponic conditions

Background and aims

Selenium is an essential micro-nutrient for animals, humans and microorganisms; it mainly enters food chains through plants. This study proposes to explore effect of inorganic Se forms on its uptake and accumulation in Zea mays.

Methods

Zea mays was grown in a controlled-atmosphere chamber for 2 weeks in a hydroponic solution of low-concentration selenium (10 μg/L (i.e.0.12 μM) or 50 μg/L (i.e. 0.63 μM) of Se). For each concentration, four treatments were defined: control (without selenium), selenite alone, selenate alone and selenite and selenate mixed.

Results

At low concentrations, selenium did not affect the biomass production of Zea mays. However, for both concentrations, Se accumulation following a selenite-only treatment was always higher than with selenate-only. Moreover, in the selenate-only treatment, Se mainly accumulated in shoots whereas in the selenite-only treatment, Se was stocked more in the roots. Interactions between selenate and selenite were observed only at the higher concentration (0.63 μM of selenium in the nutrient solution).

Conclusions

Se form and concentration in the nutrient solution strongly influenced the absorption, allocation and metabolism of Se in Zea mays. Selenate seems to inhibit selenite absorption by the roots.     

Effect of cadmium (Cd(II)), selenium (Se(IV)) and their mixtures on phenolic compounds and antioxidant capacity in Lepidium sativum

The purpose of this study was to investigate the effects of cadmium [Cd(II) as cadmium chloride], selenium [Se(IV) as sodium selenite] and their mixtures on phenolic compounds (PCs) and antioxidant activity (AOx) in Lepidium sativum. The biomass fractions corresponding to free (F1), soluble glycoside-bound (F2) and cell wall ester-bound phenolics (F3) were obtained for each treatment and PCs were screened by gas chromatography (GC-FID); F1 and F2 fractions were also analyzed by liquid chromatography with UV and fluorimetric detection. The treated plants presented different profiles of PCs as compared to controls, specifically in F1 and F2 fractions; the plant response was element-, and concentration-dependent. The cultures challenged with Cd(II) up to 5 mg L^?1, presented higher AOx with respect to controls, and this increase was associated with glycoside-bound PCs, whereas for Se(IV) the increase of AOx was less marked and associated with free PCs. Under simultaneous exposure to Cd(II) + Se(IV) (0.5–2.0 mg L^?1 each), the AOx values were relatively constant and lower than those found in the presence of Se(IV) or Cd(II) alone, providing further evidence of the protective role of Se(IV) against stress imposed by Cd(II) in this plant species. The evaluation of AOx of individual PCs and the results of principal component analysis enabled to attain several relationships among exposure conditions, antioxidant activity, free- and glycoside-bound phenolic compounds.     

Overexpression of Endogenous Anti-Oxidants with Selenium Supplementation Protects Trophoblast Cells from Reactive Oxygen Species-Induced Apoptosis in a Bcl-2-Dependent Manner

The human placenta provides life support for the developing foetus, and a healthy placenta is a prerequisite to a healthy start to life. Placental tissue is subject to oxidative stress which can lead to pathological conditions of pregnancy such as preeclampsia, preterm labour and intrauterine growth restriction. Up-regulation of endogenous anti-oxidants may alleviate placental oxidative stress and provide a therapy for these complications of pregnancy. In this study, selenium supplementation, as inorganic sodium selenite (NaSel) or organic selenomethionine (SeMet), was used to increase the protein production and cellular activity of the important redox active proteins glutathione peroxidase (GPx) and thioredoxin reductase (Thx-Red). Placental trophoblast cell lines, BeWo, JEG-3 and Swan-71, were cultured in various concentrations of NaSel or SeMet for 24 h and cell extracts prepared for western blots and enzyme assays. Rotenone and antimycin were used to stimulate mitochondrial reactive oxygen species (ROS) production and induce apoptosis. Trophoblast cells supplemented with 100 nM NaSel and 500 nM SeMet exhibited significantly enhanced expression and activity of both GPx and Thx-Red. Antimycin and rotenone were found to generate ROS when measured by 2′,7′-dichlorofluorescein diacetate (DCFDA) assay, and selenium supplementation was shown to reduce ROS production in a dose-dependent manner. Rotenone, 100 μM treatment for 4 h, caused trophoblast cell apoptosis as evidenced by increased Annexin V binding and decreased expression of Bcl-2. In both assays of apoptosis, selenium supplementation was able to prevent apoptosis, preserve Bcl-2 expression and protect trophoblast cells from mitochondrial oxidative stress. This data suggests that selenoproteins such as GPx and Thx-Red have an important role in protecting trophoblast cells from mitochondrial oxidative stress and that selenium supplementation may be important in treating some placental pathologies.     

Pre-Clinical Study for the Antidiabetic Potential of Selenium Nanoparticles

This research was delineated to explore the efficacy of selenium nanoparticles delivered in liposomes (L-Se) in the mitigation of type-2 diabetes mellitus. Adult female Wistar rats were assigned into four groups: group I, the normal control group in which the rats received normal saline solution orally; group II, the diabetic control group in which the rats were injected intraperitoneally with a single dose of streptozotocin (STZ) for induction of diabetes; group III, the metformin (Met)-treated group in which the diabetic rats were treated orally with Met; and group IV, the L-Se-treated group in which the diabetic rats were treated orally with L-Se. All treatments were delivered for 21 days. Blood and pancreas tissue samples were obtained for biochemical analysis, immunohistochemical examinations, and histopathological investigation. The L-Se-treated group showed significant drop in serum glucose and pancreatic malondialdehyde (MDA), nitric oxide (NO), tumor necrosis factor-α (TNF-α), and prostaglandin F2α (PGF2α) levels associated with significant rise in serum insulin and pancreatic glutathione, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione reductase (GR) values, in addition to significant improvement in the immunohistochemical indices (insulin and glucagon). Aforementioned results are appreciated by the histopathological findings of pancreatic tissue. In conclusion, our data have brought about compelling evidence favoring the antidiabetic potency of elemental selenium nanoparticles delivered in liposomes through preservation of pancreatic β cell integrity with consequent increment of insulin secretion and in turn glucose depletion, repression of oxidative stress, potentiation of the antioxidant defense system, and inhibition of pancreatic inflammation.     

Use of an antiarrhythmic drug against acute selenium toxicity

ObjectiveSelenium is an essential trace element. But, selenium may have toxic effects in high doses. There are no proven antidotes or curative treatments for acut selenium toxicity. Treatment involves stopping the exposure and providing supportive care for symptoms. Therefore, it is necessary to find more effective substances in the treatment of selenium toxicity. The aim of this study was to increase the survival rate of animals by supporting the heart with amiodarone and to determine the effect of amiodarone on the pathological, hematological and biochemical parameters in acute selenium intoxication.Methods64 Wistar-Albino rats were divided into four groups. Group I was given only distilled water, Group II was given 18 mg/kg dose of amiodarone, Group III was given 18 mg/kg amiodarone and 10 mg/kg sodium selenite and Group IV was given sodium selenite 10 mg/kg (LD₅₀ dose)orally.Results11 of the 16 animals in Group IV died within the first 48 h of drug administration. However, no deaths were observed in the rats in Group III. No hematological changes were observed. Biochemically, CK, CK-MB and LDH levels of Group IV were higher than the other groups on both the 2nd and 10th days. In Groups II and III, this serum level decreased, and vitamin B12 levels increased. In macroscopic inspections of the organs of Groups III and IV, slight paleness was detected. Histopathologically, degenerative changes in tissue were observed, especially in Group IV.ConclusionThis study shows that amiodarone application has a reducing effect on selenium toxicity. This was because amiodarone protected the heart by reducing CK and CK-MB levels and increased vitamin B12 levels, which play a role in the synthesis of S-adenosyl methionine that converts selenium into a nontoxic form.     

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 0.2 mg/kg Se. Group II (Se-treated group) was fed the basic diet supplemented with sodium selenite (Na₂SeO₃), and the total Se content was 2 mg/kg. Group III (Se + Cd-treated group) was fed the basic diet supplemented with Na₂SeO₃; the total Se content was 2 mg/kg, and it was supplemented with 150 mg/kg cadmium chloride (CdCl₂). Group IV (Cd-treated group) was with the basic diet supplemented with 150 mg/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.     

Influence of Selenium on Mast Cell Mediator Release

Selenium supplementation still enhanced the immune response even in individuals who, according to current standards, would be considered as not being overtly selenium deficient. Mast cells are granulated cells that play a pivotal role in allergic reactions. In this study, we investigated the modulatory effect of sodium selenite on mediator release and degranulation of murine mast cell line (MC/9). Cells were pre-treated with selenium selenite (1, 2, 3 μg/ml) for 24 h and controls left untreated. Then, cells were sensitized overnight with anti-dinitrophenyl (DNP) IgE and challenged with DNP/HSA for degranulation induction. The histamine and prostaglandin D2 (PGD2) were measured by ELISA, and β-hexosaminidase was measured by spectrophotometery method. Selenium-treated cells revealed significant decrease in concentration of PGD2 (P?=?0.019) and β-hexosaminidase (P?=?0.009). In addition, a slight reduction of histamine release by the selenium-treated cells was observed, based on our intracellular and extracellular assessments. The most inhibitory effect of selenium supplementation on mediator release of MC/9 cells was obtained in the presence of 3 μg/ml of sodium selenite. The results of the present study demonstrate beneficial effects of supplemental selenium in attenuating clinical manifestations of allergy and asthma.