Effects of selenium supplementation on selenium status of farmed fallow deer in outdoor pens

The study investigated the effects of selenium (Se) supplementation on Se status in farmed fallow deer. Fallow deer were housed on grass pasture and adapted to consume ∼200 g of pelleted grain daily. Animals were divided into two groups. One group received pelleted grain enriched with sodium selenate for 12 weeks (Se+ group, N = 10). Se intake for the first 7 weeks was 0.18 mg/kg dry matter (DM) and 0.32 mg/kg DM for the subsequent 5 weeks. The control group was fed pelleted grain without extra Se (Se− group, N = 9, 0.06-0.08 mg/kg DM). Blood samples were collected at the beginning and the end of the experiment. After the animals were slaughtered, tissue samples were collected for analysis of Se concentrations and Se-dependent glutathione peroxidase 1 (GPx1) activity. In addition, Se-independent α-glutathione-S-transferase (α-GST) activity was analyzed in liver tissue. Se supplementation significantly increased Se levels in plasma and in tissues as follows: liver > spleen > skeletal muscle > myocardium > kidney. Se supplementation also significantly increased GPx1 activity in tissues in the following order: liver > skeletal muscle > spleen = myocardium > kidneys. However, hepatic α-GST activity did not differ between Se+ and Se− groups. As expected, Se supplementation increased blood and tissue Se concentrations and GPx1 activity, which suggests a better antioxidant status. However, the activity of α-GST, an important Se-independent antioxidant enzyme, was not altered, presumably because GPx provided an adequate antioxidant capacity even though Se intake was low.     

Cellular and nephrotoxicity of selenium species

ProjectBeside its useful functions at very low concentrations, selenium including supplementary Se sources pose a potential toxicological risk. The toxicity of selenium species was tested in HaCaT cell culture and related nephrotoxicity in mice.ProcedureThe apoptotic shrinkage and necrotic expansion of cells were measured by time-lapse image microscopy. Acute nephrotoxicity was estimated upon administration of various selenium species to mice for two weeks. To confirm or to refute the accumulation of Se in the kidney and its potential chronic effect, Se concentration in kidney tissue and histopathlology were tested.ResultsThe comparison of selenium species showed that organic lactomicroSe did not affect cell growth at 5 ppm, but inorganic nanoSe severely hampered it at lower concentration (1 ppm). The in vivo Se treatment (0.5, 5, 50 ppm, corresponding to 4, 40 and 400 μg/kg) was misleading as it did neither affect the outward appearance nor the weight of the kidney. Se accumulation was observed after selenate, selenite, SelPlex, selenite and nanoSe administration, while lactomicroSe caused no traceable accumulation. In vivo, ex vivo and in vitro experiments reflected this order of selenium toxicity: selenate > selenite > SelPlex = nanoSe > lactomicroSe.ConclusionWithin the tested species lactomicroSe was the only non-nephrotoxic selenium source recommended for nutritional Se supplementation.     

Antioxidant and cytotoxic effect of biologically synthesized selenium nanoparticles in comparison to selenium dioxide

The present study was designed to evaluate antioxidant and cytotoxic effect of selenium nanoparticles (Se NPs) biosynthesized by a newly isolated marine bacterial strain Bacillus sp. MSh-1. An organic–aqueous partitioning system was applied for purification of the biogenic Se NPs and the purified Se NPs were then investigated for antioxidant activity using DPPH scavenging activity and reducing power assay. Cytotoxic effect of the biogenic Se NPs and selenium dioxide (SeO₂) on MCF-7 cell line was assesed by MTT assay. Tranmission electron micrograph (TEM) of the purified Se NPs showed individual and spherical nanostructure in size range of about 80–220 nm. The obtained results showed that, at the same concentration of 200 μg/mL, Se NPs and SeO₂ represented scavenging activity of 23.1 ± 3.4% and 13.2 ± 3.1%, respectively. However, the data obtained from reducing power assay revealed higher electron-donating activity of SeO₂ compared to Se NPs. Higher IC₅₀ of the Se NPs (41.5 ± 0.9 μg/mL) compared to SeO₂ (6.7 ± 0.8 μg/mL) confirmed lower cytotoxicity of the biogenic Se NPs on MCF-7 cell line.     

Serum selenium and selenoprotein P in patients with silicosis

ObjectivesSelenoprotein P (SeP) is a selenium (Se) supply protein, which is an antioxidant micronutrient considered to be vital for human health. The aim of this study was to assess the serum selenium status in patients with silicosis.MethodsWe conducted a retrospective case–control study where serum samples from a total of 78 patients (males with a median age of 73.5 years old) with silicosis and 20 healthy controls (males with a median age of 72.5 years old) were assayed for Se and SeP. They underwent medical and job history taking, lung function testing, and chest radiography examinations. Levels of serum Se were measured using electrothermal atomic absorption spectrophotomerty, while levels of SeP were assessed with sandwich Enzyme Immunoassay. Spearman's rank correlation test was carried out to evaluate the relationship between Se and SeP. The Mann–Whitney test was used to evaluate differences in serum Se and SeP between study groups.ResultsThe median serum Se and SeP concentrations were significantly lower in cases (74.0 μg/l and 4.2 mg/l, respectively) compared with controls (116.0 μg/l and 5.8 mg/l, respectively). In both cases and controls, serum Se was positively correlated with serum SeP (rho = 0.781, p < 0.001 and rho = 0.768, p < 0.001, respectively). Serum Se and SeP levels were significantly lower in patients classified in category four compared with those who were classified in category two or three.ConclusionsSerum Se and SeP concentrations were found to be at inadequate levels in patients with silicosis, and decreased significantly with the severity of the disease.     

Selenium accumulation in the floral tissues of two Brassicaceae species and its impact on floral traits and plant performance

Selenium (Se) is a metalloid that can occur naturally in soils from the Cretaceous shale deposits of a prehistoric inland sea in the western United States. Agricultural irrigation and runoff solubilizes Se from these shales, causing buildups of toxic levels of selenate (SeO₄²⁻) in water and soil. Our main objective was to investigate the accumulation of Se in two Brassicaceae species chosen for their potential as phytoremediators of Se contaminated soils. We tested the hypothesis that Se will accumulate in the pollen and nectar of two plant species and negatively affect floral traits and plant reproduction. Certain species of Brassicaceae can accumulate high concentrations of Se in their leaf tissues. In this study Se accumulation in plant tissues was investigated under greenhouse conditions. Se accumulator (Brassica juncea) and Se hyperaccumulator (Stanleya pinnata) plants were irrigated in sand culture with 0 μM selenate (control), 8 μM selenate, and 13 μM selenate.Nectar and pollen in S. pinnata contained up to 150 μg Se mL⁻¹ wet weight and 12900 μg Se g⁻¹ dry weight when irrigated with 8 μM selenate. Se levels in nectar (110 μg Se mL⁻¹ wet weight) and pollen (1700 μg Se g⁻¹ dry weight) were not as high in B. juncea. Floral display width, petal area and seed pod length were significantly reduced in the 13 μM selenate Se treatment in B. juncea. S. pinnata floral traits and seeds were unaffected by the Se treatments.This study provides crucial information about where some of the highest concentrations of Se are found in two phytoremediators, and may shed light on the potential risks pollinators may face when foraging upon these accumulating plants. In the field, duration of the plant's exposure, Se soil and water concentrations as well as other environmental factors may also play important roles in determining how much Se is accumulated into the leaf and floral tissues. Our greenhouse study shed light on two species’ ability to accumulate Se, as well as determined the specific plant tissues where Se concentrations are highest.     

Effects of different selenium source on selenium distribution,loin quality and antioxidant status in finishing pigs

The experiment was conducted to study the effects of different selenium source on selenium distribution, loin quality and antioxidant status in finishing pigs. A total of 108 castrates (Duroc × Landrace × Yorkshire) at average body weight (BW) of 60 kg were allotted to three treatments, each of which was replicated three times with 12 pigs per replicate (four per pen). The control groups received the basal diet containing 0.045 mg Se/kg. A 0.3 mg Se/kg in forms of sodium selenite or selenomethionine was added to the basal diet for the experimental groups. The total test period was 40 d. Results showed that selenomethionine-treatment increased the Hunter a (redness) value of meat color during 45 min, 8 and 16 h measurement period (P<0.05) and decreased the drip loss of loin muscle during 8 and 16 h measurement period (P<0.05), while sodium selenite-treatment only elevated the Hunter a value of meat color during 0.75 h measurement period (P<0.05) and had no significant effects on drip loss of loin muscle tissues. Both selenomethionine and sodium selenite-treatment increased the Se content in serum, muscle, liver, pancreas and kidney tissue (P<0.05), the level was substantially higher in muscle, liver and pancreas (P<0.05) in the selenomethionine treated group. In addition, both selenomethionine and sodium selenite-treatment increased glutathione peroxidase (GSH-Px) activity (P<0.05) and decreased the malondialdehyde (MDA) content in the liver and muscle (P<0.05) when compared with control group, but the level of magnitude was higher when selenomethionine was fed. The present study suggests that compared with sodium selenite, selenomethionine is more effective in depositing Se in tissues, enhances the antioxidant status, thus decreasing the volume of drip loss and stabilizing the meat color.     

Dietary selenium requirements based on tissue selenium concentration and glutathione peroxidase activities in old female rats

Dietary nutrient requirements for older animals have been studied far less than have requirements for young growing animals. To determine dietary selenium (Se) requirements in old rats, we fed female weanling rats a Se-deficient diet (0.007 μg Se/g) or supplemented rats with graded levels of dietary Se (0–0.3 μg Se/g) as Na₂SeO₃ for 52 weeks. At no point did Se deficiency or level of Se supplementation have a significant effect (P>0.05) on growth. To determine Se requirements, Se response curves were determined for 7 Se-dependent parameters. We found that minimum dietary Se requirements in year-old female rats were at or below 0.05 μg Se/g diet based on liver Se, red blood cell glutathione peroxidase (Gpx1) activity, plasma Gpx3 activity, liver and kidney Gpx1 activity, and liver and kidney Gpx4 activity. In conclusion, this study found that dietary Se requirements in old female rats were decreased at least 50% relative to requirements found in young, rapidly growing female rats. Collectively, this indicates that the homeostatic mechanisms related to retention and maintenance of Se status are still fully functional in old female rats.     

Enhanced cephalotaxine production in Cephalotaxus mannii suspension cultures by combining glycometabolic regulation and elicitation

To study the combination effects of glycometabolic regulator NaF and elicitor methyl jasmonate (MJ) on cephalotaxine production in Cephalotaxus mannii suspension cultures, NaF of 10 mg/L, MJ of 100 μmol/L or both of them (NaF + MJ for short below) were added to the shake-flask cultures of C. mannii cell. It was found that NaF increased the activity of glucose 6-phosphate dehydrogenase (G6PDH), but had no significant effects on phenylalanine ammonium-lyase (PAL) activity and phenols formation. In contrast, MJ could activate PAL activity and led to phenols accumulation, but had no significant effects on G6PDH activity. To explore the effects of NaF and MJ on cephalotaxine biosynthesis, harringtonine and homoharringtonine, the two cephalotaxines, were analyzed in this work. The results obtained indicated that NaF + MJ treatment showed the strongest promotion of production in all tests. Harringtonine yield in NaF + MJ treated cells (7.245 mg/L) was 4.8-fold higher than that in control cells (1.506 mg/L), 1.7-fold that in NaF-treated cells (4.12 mg/L) and 1.6-fold that in MJ-treated cells (4.458 mg/L), respectively. No homoharringtonine was found besides in NaF + MJ treated cells (0.491 mg/L). With respect of the product release rates, they were 0%, 78%, 24% and 62% in control, NaF, MJ and NaF + MJ treatment, respectively. These results suggest that the combination of NaF and MJ had contributed to the synthesis and secretion of cephalotaxine in C. mannii cells.     

Interaction between vitamin B6 and source of selenium on the response of the selenium-dependent glutathione peroxidase system to oxidative stress induced by oestrus in pubertal pig

This study aimed to assess the interaction between vitamin B₆ and selenium (Se) for the flow of Se towards the Se-dependent glutathione peroxidase (GPX) system in response to oxidative stress naturally induced by oestrus in a pubertal pig model. At first oestrus, forty-five gilts were randomly assigned to the experimental diets (n = 9/group): basal diet (CONT); CONT + 0.3 mg/kg of Na-selenite (MSeB₆0); MSeB₆0 + 10 mg/kg of HCl-B₆ (MSeB₆10); CONT + 0.3 mg/kg of Se-enriched yeast (OSeB₆0); and OSeB₆0 + 10 mg/kg of HCl-B₆ (OSeB₆10). Blood samples were collected at each oestrus (long-term profiles), and daily from day −4 to +3 (slaughter) of the fourth oestrus (peri-oestrus profiles) after which liver, kidneys, and ovaries were collected. For long-term profiles, CONT had lower blood Se than Se-supplemented gilts (p < 0.01) and OSe was higher than MSe (p < 0.01). Lower erythrocyte pyridoxal-5-phosphate was found in B₆0 than B₆10 (p < 0.01). No treatment effect was observed on GPX activity. For peri-oestrus profiles, treatment effects were similar to long-term profiles. Treatment effects on liver Se were similar to those for long-term blood Se profiles and OSe had higher renal Se concentrations than MSe gilts (p < 0.01). Gene expressions of GPX1, GPX3, GPX4, and selenocysteine lyase in liver and kidney were greatest in OSeB₆10 gilts (p < 0.05). These results suggest that dietary B₆ modulate the metabolic pathway of OSe towards the GPX system during the peri-oestrus period in pubertal pigs.     

The importance of pyridoxine for the impact of the dietary selenium sources on redox balance,embryo development,and reproductive performance in gilts

This study aimed to determine the effects of dietary pyridoxine and selenium (Se) on embryo development, reproductive performance and redox system in gilts. Eighty-four gilts were fed one of five diets: CONT) basal diet; MSeB₆0) CONT + 0.3 mg/kg of Na-selenite; MSeB₆10) diet 2 + 10 mg/kg of HCl-pyridoxine; OSeB₆0) CONT + 0.3 mg/kg of Se-enriched yeast; and OSeB₆10) diet 4 + 10 mg/kg of HCl-pyridoxine. Blood samples were collected for long-term (each estrus and slaughter) and peri-estrus (fourth estrus d −4 to d +3) profiles. At slaughter (gestation d 30), organs and embryos were collected. For long-term and peri-estrus profiles, Se level and source affected (P < 0.01) blood Se concentration whereas B₆ level increased (P < 0.01) erythrocyte pyridoxal-5-phosphate concentration. A B₆ level (P < 0.05) effect was observed on long-term plasma Se-dependent glutathione peroxidase (Se-GPX) activity whereas peri-estrus Se-GPX was minimum on d −1 (P < 0.01). Selenium level increased sows’ organs and embryo Se concentration (P < 0.01). Selenium source tended to enhance embryo Se content (P = 0.06). Within-litter embryo Se content was increased by B₆ level (P < 0.01). Selenium level tended to affect Se-GPX and total GPX activities in organs mitochondria (P = 0.09 and 0.07, respectively). Selenium source affected kidney ATP synthesis (P = 0.05). In conclusion, B₆ level affected the Se-GPX activity on a long-term basis, whereas the basal level of Se was adequate during the peri-estrus period. Embryo quality was not improved by dietary Se, and B₆ impaired within-litter homogeneity.     

Protective effect of combined therapy with dithiothreitol,zinc and selenium protects acute mercury induced oxidative injury in rats

The present study was undertaken to establish mode of action, comparative therapeutic efficacy and safety evaluation of dithiothreitol (DTT) supplemented with Zn and Se against dimethylmercury in rats. Adult male albino rats of Sprague-Dawley strain (150 ± 10 g, n = 6 per group) were exposed a bolus dose of dimethylmercury (10 mg/kg, p.o.) for once only followed by DTT (15.4 mg/kg, i.p.) along with the combination of antioxidants Zn and Se (2 mmol/kg and 0.5 mg/kg, p.o.) after 72 h of toxicant administration for three days. The results showed a significant (P ≤ 0.05) increase in the activities of AST, ALT, alkaline phosphatase, lactate dehydrogenase, in serum after toxicant administration. This was accompanied by histopathological observations. A significant rise was observed in lipid peroxidation level and mercury ion concentration however reduced glutathione content decreased in liver, kidney and brain. A significant (P ≤ 0.05) decrease in the activity of acetyl cholinesterase was also seen in different regions of brain. Combined treatment of DTT along with Zn and Se significantly (P ≤ 0.05) recouped the alterations in the enzymatic activities of serum and reversed the tissue biochemical and histopathological changes of liver, kidney and brain. Our results demonstrate that combined treatment of thiol chelator (DTT) along with antioxidants (Zn and Se) plays an important role against dimethylmercury induced tissue damage and hepatic, nephro and neurotoxicity.     

Determination of selenium and its compounds in marine organisms

In this study, we investigate the type and quantity of selenium compounds in fish and marine organisms, using ion-pair reversed phase LC–ICP-MS, developed and applied for the analysis of Atlantic cod, Atlantic salmon, Greenland halibut, Atlantic herring, blue mussel, common crab, scallop, calanus, and Euphasia super. Of the samples examined, the lowest level of selenium was found in farmed Atlantic salmon (0.17 mg Se kg⁻¹ dm). The total selenium extraction efficiency by phosphate buffer was 2.5 times higher in sea plankton and shellfish samples than in fish samples. Analysis of Se species in each hydrolysate obtained by proteolysis showed the presence of selenomethionine, which constituted 41.5% of the selenium compounds detected in hydrolysates of Atlantic herring and 98.4% of those in extracts of Atlantic salmon. Inorganic compounds, such as selenates and selenites, were detected mainly in sea plankton and shellfish samples (<0.13 mg Se kg⁻¹ wm), although no correlation was found between the presence of inorganic compounds and total selenium concentration. The accuracy of the total selenium determination was validated using a certified reference material (oyster tissue (NIST 1566b)). A lyophilised powder of cod (Gadus morhua) was used to validate speciation analysis, enzymatic hydrolysis of lyophilised powder of cod recovered 54 ± 6% of total selenium, and SeMet constituted 83.5 ± 5.28% of selenium detected in hydrolysates. The chromatographic detection limits were, respectively, 0.30 ng mL⁻¹, 0.43 ng mL⁻¹, 0.54 ng mL⁻¹, 0.55 ng mL⁻¹, 0.57 ng mL⁻¹ and 0.72 ng mL⁻¹ for selenate, selenomethionine, selenite, Se-methyl-selenocysteine, selenocystine and selenomethionine selenoxide.The data on selenium concentrations and speciation presented here could be useful in estimating levels of selenium intake by seafood consumption.     

The relationship between fetal and maternal selenium concentrations in sheep and goats

In this study, biological samples (slaughterhouse material) were collected from 30 sheep and 36 goats and classified according to gestational stage into either early or late gestation. Samples consisted of allantoic fluid, amniotic fluid, fetal liver, fetal kidney, fetal thyroid gland, maternal plasma and liver to determine selenium (Se) concentrations throughout gestation. The Se concentrations in the allantoic fluid, fetal liver and kidney increased significantly (p < 0.01) during late gestation. Concurrently, the Se concentrations in amniotic fluid, maternal plasma and liver decreased significantly (p < 0.01) over time. Significant (p < 0.01) positive relationships were recorded between the age of the fetus and Se concentrations in the allantoic fluid (r = 0.57–0.75), fetal liver (r = 0.43–0.59) and kidney (r = 0.80–0.81) in both sheep and goats. A significant (p < 0.05) positive relationships were also recorded between the Se concentrations in the allantoic fluid and fetal liver (r = 0.35–0.37), the maternal plasma and liver Se concentrations (r = 0.37–0.57) between sheep and goats. A significant (p < 0.05) negative correlation was recorded between the Se concentrations in the allantoic fluid with maternal plasma of sheep (r = −0.41) as well as between the fetal liver and maternal liver Se (r = −0.22 to 0.50) and a negative correlation (r = −0.42 to 0.43) (p < 0.01) between Se concentrations in the fetal liver and amniotic fluid in both sheep and goats, respectively. Se concentration in the fetal liver was significantly (p < 0.01) higher than that of the kidney and thyroid. In the thyroid gland no morphological differences were noted. Strong fetal–maternal relationships in Se concentration were evident throughout the gestational period and dams seem to sacrifice Se levels in order to maintain that in the fetus. Se concentrations in the amniotic and allantoic fluids could be used as a possible indicator of the Se status of the fetus throughout gestation.     

Serum selenium levels of the very low birth weight premature newborn infants with bronchopulmonary dysplasia

BackgroundThe selenium (Se) is an essential trace element that has a critical role in synthesis and activity of a number of selenoproteins with protective properties against free radical damage. This study was conducted to detect the serum Se concentration in very low birth weight (VLBW) preterm infants and its association with bronchopulmonary dysplasia (BPD).Materials and methodsCord blood Se concentration was determined in 54 neonates with gestation age 30 week or less. Another sample was obtained from these infants at day 28 of birth and serum Se levels were measured by atomic absorption spectrophotometer. All neonates were followed for oxygen dependency at 28 day after birth and 36 week postmenstrual age.ResultsThe mean cord blood Se concentration in studied neonates was 64.78 ± 20.73 μg L^?1. Serum Se concentration was 60.33 ± 26.62 μg L^?1 at age 28-day. No significant correlation was observed for serum Se concentration at birth and at one month after birth (r = ?0.04, p = 0.72). BPD was diagnosed in 25 neonates (46%). The mean serum Se concentration at one month was 57.16 ± 29.68 μg L^?1 in patients with BPD (25 cases) and 63.27 ± 23.6 μg L^?1 in 29 patients without BPD (p = 0.40).ConclusionIn our study, serum Se concentration at 28 day of birth was lower than cord blood levels in preterm neonates, but we have not found significant difference among patients who had BPD or not with respect to serum Se concentrations at this age.     

Efficacy of biogenic selenium nanoparticles against Leishmania major: In vitro and in vivo studies

Project: This study investigated the in vitro and in vivo effectiveness of biogenic selenium nanoparticles (Se NPs), biosynthesized by Bacillus sp. MSh-1, against Leishmania major (MRHO/IR/75/ER). Procedure: The 3-(4,5-dimethylthiozol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay was used to evaluate the cytotoxicity effects of the biogenic Se NPs against both promastigote and amastigote forms of L. major. In a separate in vivo experiment, we also determined the preventive and therapeutic effects of biogenic Se NPs in BALB/c mice following subcutaneous infected with L. major. Results: The MTT assays showed that the highest toxicity occurred after 72 h against both promastigote and amastigote forms of L. major. The cytotoxicity of Se NPs was higher at all incubation times (24, 48, and 72 h) against the promastigote than the amastigote form (p < 0.05). The 50% inhibitory concentrations (IC₅₀) of the Se NPs were 1.62 ± 0.6 and 4.4 ± 0.6 μg ml^?1 against the promastigote and amastigote forms, respectively, after a 72-h incubation period. Apoptosis assays showed DNA fragmentation in promastigotes treated with Se NPs. In an animal challenge, prophylactic doses of biogenic Se NPs delayed the development of localized cutaneous lesions. Moreover, daily administration of Se NPs (5 or 10 mg kg^?1 day^?1) in similarly infected BALB/c mice that had not received prophylactic doses of Se NPs also abolished the localized lesions after 14 days. Conclusion: Based on these in vitro and in vivo studies, biogenic Se NPs can be considered as a novel therapeutic agent for treatment of the localized lesions typical of cutaneous leishmaniasis.     

Serum and urinary selenium levels in obese children: A cross-sectional study

ObjectiveTo determine serum and urinary selenium (Se) levels in children with and without obesity, and to assess if Se influences the risk of obesity.Subjects and methodsHigh-resolution-continuum source-atomic absorption spectrometry (HR-CS-AAS) was used to determine the content of Se in 80 children (age 6–17; 40 boys, 40 girls). Correlations between variables were tested with the use of Spearman's correlation coefficient. U Mann–Whitney test was applied to assess the difference of Se contents in samples. Measured metabolic risk factors (blood pressure, glucose level, triglycerides (TG), low-density lipoprotein (LDL), high-density lipoprotein (HDL), and total cholesterol), age, gender, and BMI were correlated. Logistic regression models were fitted to identify predictors of obesity interacting with selenium content in serum and urine, separately.ResultsObese children, regardless of gender, had lower Se content. Se level in serum (p = 0.001, OR 0.74, 95%CI 0.62–0.88) and total cholesterol (p = 0.001, OR 1.19, 95%CI 1.08–1.31) were the independent factors significantly influencing the risk of obesity in children. Two separate models were observed for Se in urine: (i) Se level (p < 0. 0001, OR 0.70, 95%CI 0.58–0.84) and glucose level (p < 0.0001, OR 1.22, 95%CI 1.10–1.35), and (ii) Se level (p = 0.002, OR 0.60 95%CI 0.43–0.83) and total cholesterol level (p = 0.003, OR 1.16, 95%CI 1.05–1.28).ConclusionThe current study suggests a possible role of Se in obesity. Further research needs to be performed to check if obese children are an at-risk group for Se deficiency.     

Biomarkers in critically ill patients with systemic inflammatory response syndrome or sepsis supplemented with high-dose selenium

ObjectiveLow levels of selenium (Se) and glutathione peroxidase (GSHPx), a key selenoenzyme, were documented in systemic inflammatory response syndrome (SIRS) and sepsis, both associated with high mortality. Se supplementation had mixed effects on outcome. We hypothesized that Se supplementation could have a different impact on biomarkers and 28-day mortality in patients with SIRS vs. sepsis.MethodsAdult patients with SIRS or sepsis were randomized to either high-dose (Se+, n = 75) or standard-dose (Se−, n = 75) Se supplementation. Plasma Se, whole blood GSHPx activity, C-reactive protein (CRP), procalcitonin (PCT), prealbumin, albumin and cholesterol levels were measured serially up to day 14.ResultsThere was no difference in mortality between Se− (24/75) vs. Se+ group (19/75; p = 0.367) or between SIRS and septic patients (8/26 vs. 35/124; p = 0.794). There was a trend to reduced mortality in SIRS patients in the Se+ vs. Se− group (p = 0.084). Plasma Se levels increased in the Se+ group only in patients with sepsis but not in patients with SIRS. Plasma Se levels correlated with GSHPx. In SIRS/Se+ group, Se correlated only with GSHPx. In SIRS/Se− group, Se correlated with cholesterol but not with other biomarkers. In sepsis patients, Se levels correlated with cholesterol, GSHPx and prealbumin. Cholesterol levels were higher in survivors in the Se− group.ConclusionsSe levels correlated with GSHPx activity and other nutritional biomarkers with significant differences between SIRS and sepsis groups. High-dose Se supplementation did not affect mortality but a strong trend to decreased mortality in SIRS patients warrants further studies in this population.     

Soils selenium level and esophageal cancer: An ecological study in a high risk area for esophageal cancer

ProjectGolestan province, located in northeast of Iran, has been known as a high risk area for esophageal cancer (EC). This study was conducted to assess the relationship between soils selenium (Se) level and development of EC in this region.ProceduresIn this ecological study, 135 blocks were identified in Golestan province based on geographical altitude and longitude on the map. One soil sample was collected from the center of each block. Then we investigated Se concentration in soil samples by flame atomic absorption spectrometry. Statistical analysis was performed by the Pearson correlation test and Student t-tests. P-values of less than 0.05 were considered as significant.ResultsThe mean±SD of soils Se level in Golestan province was 3.7±1.61 mg/kg. There was a positive correlation between soils Se level and EC rates in this area (P=0.03) (Pearson correlation coefficient=0.19). Soils Se concentration was significantly higher in high (4.13 mg/kg) than in the low (3.39 mg/kg) EC rate areas (P=0.01).ConclusionsWe found high soils Se concentration and a significant positive relationship between soils Se level and EC rate in Golestan province of Iran. So, high soils Se level may play a possible role in developing EC in this area, specifically in Turkmensahra (very high EC rates).     

The effects of di(2-ethylhexyl) phthalate and/or selenium on trace element levels in different organs of rats

Di(2-ethylhexyl)phthalate (DEHP), a widely used plasticizer for synthetic polymers, is known to have endocrine disruptive potential, reproductive toxicity, and induces hepatic carcinogenesis in rodents. Selenium (Se) is a component of several selenoenzymes which are essential for cellular antioxidant defense and for the functions of mammalian reproductive system. The present study was designed to investigate the effects of DEHP exposure on trace element distribution in liver, testis, and kidney tissues and plasma of Se-deficient and Se-supplemented rats. Se deficiency was produced by feeding 3-week old Sprague-Dawley rats with ≤0.05 mg Se/kg diet for 5 weeks, and supplementation group were on 1 mg Se/kg diet. DEHP treated groups received 1000 mg/kg dose by gavage during the last 10 days of feeding period. Se, zinc (Zn), copper (Cu), iron (Fe) and manganese (Mn) levels were measured by inductively coupled plasma mass spectrometry (ICP-MS). Se supplementation caused significant increases in hepatic, renal, and testicular Se levels. With DEHP exposure, plasma Se and Zn, kidney Se, Cu and Mn levels were significantly decreased. Besides, liver Fe decreased markedly in all the DEHP-treated groups. Liver and kidney Mn levels decreased significantly in DEHP/SeD group compared to both DEHP and SeD groups. These results showed the potential of DEHP exposure and/or different Se status to modify the distribution pattern of essential trace elements in various tissues, the importance of which needs to be further evaluated.