Selenium Concentrations In Organs Research Articles

Effects of Organic Selenium and Nanoselenium on Drought Stress of Pak Choi (Brassica chinensis var. pekinensis. cv. ‘Suzhouqing’) and Its Transcriptomic Analysis

In order to investigate physiological and molecular mechanisms underlying the impacts of organic selenium and nanoselenium on the drought stress of pak choi (Brassica chinensis var. pekinensis. cv. ‘Suzhouqing’), we sprayed 20 mL of 0, 5, 10, 20 mg L−1 concentrations of organic selenium (DCK, DO5, DO10, DO20) and nanoselenium (DN5, DN10, DN20). We measured photosynthetic pigment, antioxidant and nutritional quality, performed transcriptome sequencing of leaves using RNA-seq technology, obtained 297,176,114 clean sequences, and identified differential expressed genes. Organic selenium and nanoselenium increased the photosynthetic capacity by upregulating light-trapping pigment proteins, regulated reactive oxygen species homeostasis by activating the antioxidant system through the upregulation of glutathione S-transferase, and maintained water homeostasis through glutathione oxidase activity, thus enhancing weight. They contributed to the elevated total selenium content by increasing expression levels of ABC transporter, adenylate kinase, and cysteine desulphurase. Additionally, hub genes related to these metabolic pathways were identified using a weighted gene coexpression network analysis. The consistent results with the upregulated genes identified in the Kyoto Encyclopedia of Genes and Genomes pathway confirmed the accuracy and reliability of the transcriptome sequencing data. This study provides scientific reference to further in-depth research on the molecular effect of selenium on crops under drought stress conditions.

Potential of microalgae as source of health-beneficial bioactive components in produced eggs.

In line with the growing interest in humans' nutrition, production of microalgae-based functional foods characterized by an increased content of bioactive substances is attractive. The aim of this study was to investigate the potential of microalgae as additives to feed for laying hens, to enrich the eggs with polyunsaturated fatty acids (PUFA) and selenium/carotenoid antioxidants. Our results showed that supplementation of hens by feed containing 1% of Trachydiscus minutus or 1% of Japonochytrium marinum leads to increase of long-chain PUFA in eggs by 26-66%. Addition of 1% of Scenedesmus obliquus to feed causes the increase of lutein and cantaxanthin in eggs by 48% and 18%, respectively, and addition of 0.5% selenium enriched Chlorella vulgaris increases the final content of organic selenium in eggs by 100-152%. As concerns selenium, it is important to notice that its bioavailability has to be considered. Despite the higher concentration of total selenium in Vischeria helvetica than in C. vulgaris, its bioaccessibility in Vischeria was limited, thus out of usage for feeding purposes. Administration of combinations of selenium enriched Chlorella + Japonochytrium and Chlorella + Schizochitrium verified the increased concentrations of organic selenium, PUFA, as well as carotenoids, with no adverse effect on quality and productivity of eggs. The study confirmed the potential of both traditional as well as new microalgae to be used as feed supplements for functional eggs production. The supplementation of hens by specific microalgae combinations could be advantageous in terms of spectrum of bioactive compounds present.

Effect of organic selenium dietary supplementation on quality and fertility of cryopreserved chicken sperm

Oxidative stress due to cryopreservation has been considered as a major factor in sperm damage. Supplementation of the diet with different concentrations of organic selenium has been proposed to improve the quality of fresh and frozen–thawed semen in different breeds of roosters. Sixteen Pradu Hang Dum (Thai native) and 16 Rhode Island Red roosters were used in this study. Four levels of selenium supplementation between 0 and 0.9 ppm were examined. After 14 days of feeding, semen samples were collected twice a week and the fresh semen was evaluated. Then semen from each group was pooled and cryopreserved. The fertility of frozen–thawed semen was determined by inseminating 48 layer hens. Supplementation of diets with 0.3, 0.6 and 0.9 ppm selenium improved the fresh semen in terms of sperm viability and normal morphology (P < 0.01). Sperm concentration increased (quadratically, P < 0.001) with increasing dietary selenium levels. Meanwhile, post-thawed semen quality in terms of sperm motility, viability, live with intact acrosome and functioning mitochondria improved significantly with selenium treatments of 0.6 and 0.9 ppm, and lipid peroxidation was decreased (P < 0.001) and fertility improved (P < 0.05) with those levels of selenium treatment. In addition, there were differences between breeds with respect to some fresh or frozen semen quality parameters (P < 0.05). In conclusion, the breed affected both fresh and frozen semen. Even there were no statistically significant differences in the parameters from groups 0.6 and 0.9 ppm on frozen-thawed semen quality, but the highest sperm concentration was found in 0.6 ppm. Therefore selenium supplementation of diets at 0.6 ppm was recommended to improve the quantity and quality of fresh and frozen semen.

Effects of Organic Selenium on the Physiological Response, Blood Metabolites, Redox Status, Semen Quality, and Fertility of Rabbit Bucks Kept Under Natural Heat Stress Conditions.

Heat stress can impair the general health of rabbit bucks by disturbing physiological homeostasis with negative consequences in animal welfare and remarkable decline in reproductive performance. Selenium (Se) can control a number of vital biological processes. Thus, the effects of organic selenium (OSe) supplementation on the blood metabolites, redox status, semen quality, testicular histology, seminal plasma protein profile, and fertility of rabbit bucks kept under natural heat stress conditions were studied. Adult V-line male rabbits were fed a basal diet supplemented with 0.3 mg OSe/kg dry matter (DM) diet (OSe, n = 9) or not (control, CON, n = 9) for 12 weeks. The results showed that rabbits fed the OSe diet had 73.68 and 68.75% higher (P < 0.05) OSe concentrations in the blood serum and seminal plasma, respectively, than rabbits fed the CON diet. The OSe diet significantly decreased the rectal temperature and respiration rate and significantly increased the blood serum concentrations of total protein, albumin, glucose, and glutathione peroxidase compared to the CON diet. Rabbits fed the OSe diet had lower reaction times (12.53 vs. 5.84 s, ± 0.79, P < 0.01) and higher total functional sperm counts (116.74 vs. 335.23 × 106/ml, ± 24.68, P < 0.001) and percentages of integrated sperm membranes (60.38 vs. 79.19%, ± 1.69, P < 0.01) than rabbits fed the CON diet. Rabbits fed the OSe diet had higher (P < 0.01) contents of seminal plasma total protein, albumin, alanine transaminase, fructose, and total antioxidant capacity and lower (P < 0.001) malondialdehyde (MDA) levels than those fed the CON diet. Rabbits fed the OSe diet had sperm cells with higher levels of integrated DNA than those fed the CON diet. The seminal plasma of rabbits fed the OSe diet contained four new proteins, with molecular weights of 19.0, 21.5, 30.0, and 44.0 kDa. The kindling rates, litter size, and weight at birth of females mated with males fed the OSe diet were significantly higher than those of females mated with males fed the CON diet. In summary, the inclusion of 0.3 mg OSe/kg DM diet of naturally heat-stressed rabbit bucks countered the negative impacts of elevated environmental temperature on physiological homeostasis, semen quality, and fertility.

A comparison of selenium concentrations in selected organs of wild boar (Sus scrofa) from industrialized and non-industrialized regions of Poland

The aim of this study was to compare selenium concentration in the liver and kidneys of wild boar inhabiting industrialized and non-industrialized regions of Poland. Selenium concentrations in organs were determined using spectrofluorometric method. In all the animals studied, Se concentrations were a few times lower than in kidneys which may indicate too low content of this element either in the boar’s diet or the presence of a poorly absorbable form of Se. No statistically significant differences were noted in the mean Se concentrations in the liver and kidney of wild boar from industrialized and non-industrialized areas. In the case of wild boar, it seems that the level of selenium in their organs is more dependent on geochemical conditions in the specific feeding ground than on the scale of regional industrialization, and that this situation is most likely related to the specificity of wild boar feeding.

Wild boars (Sus scrofa) as bioindicators of environmental levels of selenium in Poland

The objective of the study was to determine selenium content in selected organs (liver, kidney) of wild boars from different regions of Poland. Materials for the study were obtained from 28 sites located in 16 provinces of Poland. Selenium concentrations in organs were determined using spectrofluorometric methods after wet mineralization in HNO3 and HClO4 mixture. Mean selenium concentrations in the investigated wild boars from Poland were 0.230 μg/g wet weight in the liver and 1.327 μg/g w.w. in the kidneys. Hepatic and nephric Se concentrations ranged from 0.036-0.626 μg/g w.w. and 0.322-4.286 μg/g w.w., respectively. Selenium concentrations in the wild boars differed considerably according to geographical location. Concentrations of selenium were highest in wild boars from south-eastern provinces and lowest in animals from northern provinces. Most of Poland's area is environmentally deficient in this trace element, as evidenced by marginal selenium levels in the organs of the wild boars.

Long-term organic selenium supplementation overcomes the trade-off between immune and antioxidant systems in pacu (Piaractus mesopotamicus)

Selenium (Se) is an essential nutrient for antioxidant defenses in fish because of its role in preventing immunosuppression caused by oxidative stress. In this study it was demonstrated the relation between the oxidative stress and immune status after a long Se supplementation period, as a result of the evaluation of immunological, hematological and antioxidant responses, as well as growth performance of pacu fed diets supplemented with different concentrations of organic selenium (0, 0.3, 0.6, 0.9, and 1.8 mg Se-yeast/kg, but the final analyzed selenium concentrations were 0.72, 0.94, 1.15, 1.57 and 2.51 mg/kg, respectively) for 65 days. Dietary Se supplementation at 1.15 mg Se-yeast/kg (analyzed value) restored the production of antioxidant enzymes (glutathione peroxidase (GPx) and glutathione S-transferase (GST)), and consequently allowed the increased of some immunological parameters (leukocyte respiratory burst activity and lysozyme activity), hematological parameters (red blood cell count (RBC), hematocrit (HTC), mean corpuscular volume (MCV), and white blood cell count (WBC)). Se supplementation in pacu diets at 1.15 mg Se-yeast/kg for 65 days improved immune response and antioxidant defenses, suggesting that oxidative stress impairs immune system response to prevent excessive reactive oxygen species in cells and indicating the occurrence of a physiological trade-off between immune and antioxidant systems. Higher Se levels, such as 1.57 mg Se-yeast/kg increased the leukocyte respiratory burst activity, the WBC and thrombocyte counts, the RBC and HTC, and the GST and GPx enzymes. However, 2.51 mg Se-yeast/kg decreased the lysozyme levels, the WBC and thrombocyte counts, the RBC, HTC and MCV, and the GST and GPx enzymes. Those findings are important to future studies because showed the negative effect of oxidative stress on immunity, and may help to prevent any inhibition of the expected immune response after immunomodulators administration and vaccination. Also it was possible to meet the dietary selenium requirement of pacu, that was estimated to be 1.56 mg/kg.

Selenium Content in Selected Organs of Roe Deer (Capreolus capreolus) as a Criterion to Evaluate Environmental Abundance of this Element in Poland

Due to the fact that a considerable part of Europe, including some regions of Poland, isconsidered to be deficient in selenium, it seems necessary to develop a selenium map for different regions of Poland, which will be used in future to prepare a prophylaxis programme against selenium deficiency inanimals. The aim of the study was to determine selenium content in selected organs (liver and kidneys) of roe deer from different regions of Poland as an indirect method of assessing environmental abundance of this element. Material for the study was collected from 28 sites located in 15 provinces of Poland. Seleniumconcentrations in organs were determined using spectrofluorometric methods. Mean selenium concentration in roe deer from Poland was 0.088 μg/g wet weight (w.w.) in liver and 0.503 μg/g w.w. in kidneys. Organ selenium concentrations in the studied animals varied considerably according to geographical location. Most areas of Poland are deficient in environmental selenium, as evidenced by the low content of this element in the organs of roe deer.

Tissue Distribution of Selenium and Effect of Season and Age on Selenium Content in Roe Deer from Northwestern Poland

The aim of the study was to compare selenium concentrations in different organs of roe deer from northwestern Poland. Samples of liver, kidneys, heart and lungs, collected from 74 roe deer shot during the hunting seasons of 2008-2009 in northwestern Poland, were studied. Selenium concentration in the organs was determined spectrofluorimetrically. Mean selenium concentration was 0.06 µg/g w.w. in the liver, 0.41 µg/g w.w. in the kidneys and 0.05 µg/g w.w. in the heart and lungs. Season had a significant effect on selenium concentration in the liver, kidneys, lungs and heart. In all the organs, the highest selenium concentration was found in spring and the lowest in autumn and winter. All animals studied were deficient in selenium. The low selenium concentration in the liver or heart can disturb their function, and in the future, it may be a factor contributing to the population decline of roe deer in the northwestern part of Poland.

Enrichment of African catfish with functional selenium originating from garlic

We wanted to create functional seafood with high concentrations of organic selenium (seleno-methyl-selenocysteine and ?-glutamyl-seleno-methyl-selenocysteine) with anti-carcinogenic properties for human consumers. Garlic containing high concentrations of these organic selenium compounds was used as a selenium source in five experimental feeds for African catfish (1.9, 2.8, 3.9, 5.1 and 8.5 mg kg?1 Se); a sixth experimental feed was formulated without garlic (1.9 mg kg?1 Se). The experimental feeds were fed to African catfish [initial mean (SD) weight 100.7 (2.7) g] for 43 days with three replicates per treatment. Whole fish fillets were sampled for total selenium analysis (start and end) and selenium speciation (end). We found a positive linear relationship between dietary and fillet concentrations for total selenium and selenomethionine. The dietary total selenium concentration of 8.5 mg kg?1 resulted in a total selenium concentration of 0.9 mg kg?1 in the fillet (wet tissue). The majority of the selenium compounds recovered in an extract made from the fillet consisted of selenomethionine, considered to be important from a nutritional point of view. Seleno-methyl-selenocysteine, one of the organic selenium species to which superior anti-carcinogenic properties are attributed, was detected in the fillet but could not be quantified.

Selenium (IV), selenium (VI) and organic selenium in Lake Biwa, the Yodo River and Osaka Bay.

Selenium in natural waters was chemically specified at 16 stations from Lake Biwa to Osaka Bay. The concentrations of selenium (IV), selenium (VI) and organic selenium in Lake Biwa ranged from 0.04 to 0.36, from 0.00 to 0.36, and from 0.00 to 1.97 nM, respectively. The concentration of organic selenium was highest at the depth of the maximal of chlorophyll a concentration in the Lake Biwa water. The concentrations of selenium (IV), selenium (VI) and organic selenium in the Yodo River ranged from 0.12 to 0.37, from 0.02 to 0.32, and from 0.32 to 0.18 nM, respectively. In coastal Osaka Bay, the concentrations of selenium (IV), selenium (VI) and organic selenium ranged from 0.05 to 0.31, from 0.09 to 0.50, and from 0.14 to 0.77 nM, respectively.

Studies on serum tocopherol, selenium levels and blood glutathione peroxidase activities in calves with white muscle disease.

For the purpose of clarifying the cause of white muscle disease (WMD) in calves, tocopherol and selenium levels and blood glutathione peroxidase (GSH-Px) activity were measured on 10 calves with WMD and nine of their dams. The main clinical symptoms of the 10 calves with WMD were motor disturbances including recumbency and stiffness. Serum enzyme activities (GOT, GPT, CPK, LDH) in calves with WMD increased markedly, and this increase was also observed in some of their dams. Serum tocopherol levels of calves with WMD were low, 70% of which showing deficient levels of less than 70 micrograms/100 ml. Serum selenium levels of all the calves were lower than 35 ppb, indicating a deficiency, and were accompanied by low blood GSH-Px activity. alpha-Tocopherol and selenium concentrations in organs were very low. Dams of calves with WMD showed low serum tocopherol levels, 22% of which indicating deficient levels below 150 micrograms/100 ml. Serum selenium levels in dams showed a marked decrease to under 20 ppb, and also low blood GSH-Px activity. Feedstuffs supplied in the farms to affected calves indicated very low alpha-tocopherol contents (below 3 mg/100g DM) and low selenium concentrations below 50 ppb in DM. It was concluded that WMD in calves was attributable to nutritional muscular dystrophy caused by deficiencies in tocopherol and selenium in feedstuffs supplied to their dams.

Effects of barley-bound organic selenium compared with inorganic selenite on selenium concentration and structure of tissues in pig

A study was made of the effects of barley feeds containing varying levels of natural grain selenium derived from fertilizer and of the effects of sodium selenite on selenium concentrations in the tissues of growing pigs and on the histological structure of myocardium and longissimus muscle. The results indicated that organic grain selenium affects the selenium levels of porcine tissues significantly more than sodium selenite supplementation of the same amount. The organic selenium concentrations of feed and organs were found to be linearly correlated. Spleen, lung and heart were the most reliable indicators of tissue selenium level in pigs. The selenium concentration of muscles of pigs fed on naturally seleniferous feed (270 µg Se/kg DM) was at the internationally level (500 µg Se/kg DM in meat), whereas the same amount of selenite in feed increased the selenium level of muscle only slightly (to 200/µg Se/kg DM). The histological structures of heart and muscle of pigs fed on naturally seleniferous feed were normal, whereas in the selenite group there were signs of muscle dystrophy when the selenium level was below 200 µg Se/kg DM. In addition, the pigs given selenite were subsequently placed in a lower, fat-containing carcass class. Feed with a natural organic selenium level of 150—200 µg Se/kg DM is preferred to selenite selenium supplement in pork production.

Organic and colloidal selenium in Southern Chesapeake Bay and adjacent waters

River water, estuarine water and coastal seawater were collected and filtered through glass-fiber filters. Subsamples of these three types of waters were subsequently passed through AMICON DIAFLO ultrafilters (UM 2, YM 5 and YM 10) individually. The filtrates were analyzed for dissolved selenium with and without oxidation by irradiation with ultraviolet (UV) light and for dissolved organic carbon (DOC). The concentration of organic selenium is calculated as the difference in the concentrations of selenium with and without UV oxidation. The contribution of colloidal inorganic selenium to total dissolved inorganic selenium decreases with increasing salinity. Colloidal inorganic selenium constitutes 77, 40 and 0% of the total dissolved inorganic selenium in river water, estuarine water and coastal seawater, respectively. Most of the colloidal inorganic selenium is found in material having nominal molecular weights (NMW) between 1000 and 5000. Organic selenium is detected in all three types of waters. The ratio of organic to inorganic selenium ranges from 0.66 to 1.58. The lowest ratio was observed in river water. Colloidal organic selenium was also found in all three types of waters. Its contribution to total dissolved organic selenium again decreases with increasing salinity. Colloidal organic selenium constitutes 70, 64 and 35% of total dissolved organic selenium in river water, estuarine water and coastal seawater, respectively. Most of the organic selenium is found in material having low NMW. For a given sample, except in the subsample of river water containing material with NMW above 10 000, the concentrations of organic selenium in the filtrates are linearly related to those of DOC.

Sulfur--selenium studies in sheep. II. Effect of a dietary sulfur deficiency on selenium and sulfur metabolism in sheep fed varying levels of selenomethionine.

The effect of a sulfur deficiency on the metabolism of selenium and sulfur was investigated in eight merino wethers. The sheep were fed high-sulfur (2 g S/kg) or low-sulfur (0.5 g S/kg) diets for two periods of 35 days each, and received selenium as selenomethionine at dietary concentrations of 0.02, 0.06, 0.09 and 0.67 mg Se/kg. Sheep fed the low-sulfur diet had reduced feed intake, reduced nitrogen, sulfur and selenium balance, but elevated plasma and wool selenium concentrations. Selenium concentrations in organs and tissues of slaughtered animals paralleled the selenium intake of the animal, with the renal cortex containing the highest concentration and bone the lowest. The effect of the 0.5 g S/kg diet on feed intake is in contrast with the results from the previous experiment (White and Somers 1977) using 0.7 g S/kg. It is this difference in fed intake which was responsible for many of the effects on selenium metabolism observed in this experiment. Once the feed intake effects are accounted for, the implications for sulfur--selenium interactions remain as before, i.e. more selenium is incorporated into wool and plasma protein when dietary sulfur is limiting than when it is not.