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Selenium (Se) is closely associated with kidney disease, and renal injury often occurs together with hyposelenemia. This study was designed to reveal the mechanism underlying renal injury induced by Se deficiency in pigs. Twenty-four castrated male Yorkshire pigs were divided into two groups fed either a Se-deficient diet (0.007 mg Se per kg) or a Se-adequate diet (0.3 mg Se per kg). Serum and kidney samples were collected at the 16th week of the trial, processed, and analyzed for serum biochemistry, Se concentration, kidney index markers, histology, selenoprotein mRNA expression, redox status, and inflammatory cytokines. Dietary Se deficiency induced kidney injury, decreased (P > 0.05) Se concentrations, and increased (P > 0.05) kidney index and serum blood urea nitrogen, creatinine, and carbon dioxide values. Histological analysis indicated that Se deficiency induced inflammatory lesions and renal tubular atrophy in the renal medulla. Se deficiency downregulated (P > 0.05) nine selenoprotein genes (GPX1, SELENOW, SELENOH, SELENOP, GPX3, TXNRD2, SELENOI, SELENON, and SELENOM) and upregulated (P > 0.05) SEPHS2 in the kidneys. Se deficiency decreased (P > 0.05) the activity of glutathione peroxidase, thioredoxin reductase, and catalase, as well as the hydroxyl radical inhibition capacity, and increased (P > 0.05) the content of malondialdehyde and nitric oxide. Se deficiency increased (P > 0.05) the expression of the transcription factors NF-κB and HIF-1α, and regulated inflammatory cytokines. Se deficiency increased (P > 0.05) the expression of IL-6, IL-8, IL-12, IL-17, and cyclooxygenase-2, and decreased (P > 0.05) the expression of IL-10, IL-13, and TGF-β. These results indicated that Se deficiency induces kidney injury through the regulation of selenoproteins, oxidative stress, and inflammation.

BACKGROUND The aim of this study was to investigate the metabolism of α-tocopherol derived from vitamin E-enriched transgenic maize (VER) and its effects on antioxidant and immune functions in broilers aged 1-42 days. A total of 360 1-day-old male broilers were randomly divided into three groups containing six replicates with 20 broilers per replicate. The negative control (NC) group and the positive control (PC) group were given non-GM maize and non-GM maize plus exogenous vitamin E (VE), respectively, and the VER group was given VER, replacing the non-GM maize given to the NC group. Between days 1 and 21 and days 22 and 42, VE levels were 4.38 and 4.63 mg kg-1 in the NC group, and 14.11 and 14.91 mg kg-1 in the PC and VER group, respectively. RESULTS The results showed that α-tocopherol from both VER and additives increased α-tocopherol transfer protein and cytochrome P450 concentrations. Serum α-tocopherol and α-tocopherylquinone levels of broilers in the PC and VER groups were also significantly higher than those in the NC group (P

Background The immune system is one aspect of health that is affected by dietary selenium (Se) levels and selenoprotein expression. Spleen is an important immune organ of the body, which is directly involved in cellular immunity. However, there are limited reports on Se levels and spleen health. Therefore, this study established a Se-deficient pig model to investigate the mechanism of Se deficiency-induced splenic pathogenesis. Methods Twenty-four pure line castrated male Yorkshire pigs (45 days old, 12.50 ± 1.32 kg, 12 full-sibling pairs) were divided into two equal groups and fed Se-deficient diet (0.007 mg Se/kg) or Se-adequate diet (0.3 mg Se/kg) for 16 weeks. At the end of the trial, blood and spleen were collected to assay for erythroid parameters, the osmotic fragility of erythrocytes, the spleen index, histology, terminal deoxynucleotidyl transferase nick-end labeling (TUNEL) staining, Se concentrations, the selenogenome, redox status, and signaling related inflammation and apoptosis. Results Dietary Se deficiency decreased the erythroid parameters and increased the number of osmotically fragile erythrocytes (P P COX-2 and iNOS (P Caspase3, Caspase8, and Bak), and downregulated antiapoptotic genes (Bcl-2) (P Conclusions These results indicated that Se deficiency induces spleen injury through the regulation of selenoproteins, oxidative stress, inflammation and apoptosis.

A naphthalimide-based fluorescent probe, Nap-I, with iodoacetamide as the alkylating group, has been synthesized, and its specific fluorescent staining of proteins containing cysteine (Cys) and selenocysteine (Sec) residues in sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) has been evaluated. This molecule shows good fluorescence properties in the labeling of protein Cys/Sec residues, while reducing steric hindrance and minimizing changes in the water solubility of proteins. Reaction parameters, such as labeling time and pH, have been investigated, and the optimal labeling conditions for Cys-containing proteins have been determined. Thioredoxin reductase (TXNRD) is best stained at low pH. The probe Nap-I has been successfully used for the quantification of serum proteins and hemoglobin in Tan sheep serum, and TXNRD in Tan sheep liver and muscle has been labeled at low pH. Based on the probe Nap-I, we have also distinguished TXNRD1 and TXNRD2 by SDS-PAGE. The results showed that, compared with the normal microenvironment in which the protein resides, the lower the pH value, the greater the TXNRD activity.

An “off–on” fluorescent probe, Nap-DNB, which is based on naphthimide, was designed and developed for the detection of biological selenols in vitro. We have adopted a combination of a low-pH detection environment and reaction sites that are more difficult to destroy to avoid the interference of a large number of biological thiols in biological samples. Nap-DNB can completely respond to selenocysteine within 15 mins, with a detection limit of 92 nM. Nap-DNB was successfully used for the detection of selenols in the serum, liver, and longissimus dorsi of selenium-enriched Tan sheep. Through comparison, we found that the detection of selenols by the Nap-DNB is similar to that by thioredoxin reductase and glutathione peroxidase in a commercial kit method. Nap-DNB can be used for the detection of selenols in selenium-enriched Tan sheep.

This study was conducted to evaluate the influence of dietary supplementation with different levels of selenium yeast (SeY) on growth performance, carcass characteristics, antioxidant capacity and meat quality of Tan sheep. Sixty-four (n=64) five-month-old male Tan sheep with an initial body weight of 32 ± 1.95 kg (BW ± SD) were selected and randomly assigned to four treatments with 16 replicates of one sheep each. The four groups received a basal diet (0.16 mg Se/kg) supplemented with 28.94, 105.46, 258.51, 564.60 mg/kg SeY to final dietary selenium (Se) concentrations of 0.25 (Se0.25), 0.5 (Se0.5), 1.0 (Se1.0), or 2.0 (Se2.0) mg/kg for 60 days, respectively. The feed-to-weight gain ratio showed a quadratic significant change of first increasing and then decreasing with the increase of dietary SeY supplemental level (p 0.25 mg/kg markedly decreased the GR value of the sheep (p 0.25 mg/kg significantly enhanced muscle thioredoxin reductase activity (p 0.05). Moreover, final dietary Se at >0.25 mg/kg was associated with significant decreases in the lightness and yellowness values of muscle tissues at 45 min (p 0.05). Meat color of mutton had a less change over time in the Se0.5 group, and the color stability was better. Drip loss of muscle decreased significantly with an increase in dietary SeY supplementation (p

The solubilities of 2-tert-butylanthraquinone (TBAQ) in three binary solvents 1,3,5-trimethylbenzene (TMB) + 2,6-dimethyl-4-heptanol (diisobutylcarbinol, DIBC) with 3:1, 3:2, 1:1 and 2:3 in the volume ratio of TMB to DIBC (solvent ratio) were determined in the temperature range from 303.15 to 333.15 K by the equilibrium method. As a comparison, the solubilities of TBAQ in solvent mixtures TMB + 2-methylcyclohexyl acetate (MCA) and TMB + trioctylphosphate (TOP) were also determined. The solubilities of TBAQ in all the binary solvents always increased with rising temperature and solvent ratio. At the same temperature and solvent ratio, the solubilities of TBAQ in TMB + DIBC were close to those in TMB + MCA and much higher than those in TMB + TOP. Two activity coefficient models NRTL equation, Wilson equation and modified λ–h equation were applied to correlate and predict the solubilities of TBAQ in mixed solvents. The satisfactory correlation were obtained using all three equations and the NRTL equation gave relatively good prediction with the average and maximum relative deviation of 1.87% and 5.06%, respectively.