Antitumour Activity of Chitosan Hydrogen Selenites

Chitosans reacted with selenious acid to prepare chitosan hydrogen selenites, which were found to be growth-inhibitory against sarcoma 180 solid tumor. The results indicated that the activity also depended on the molecular weight of chitosan supports.

Syntheses, Structures, and Some Properties of Three Vanadium Selenites

Three novel vanadium selenites with the formulae [（VO2）（1,10-phenanthtoline）（SeO3H）]2 1, [（VO2）（2,2′-bipyridine）]2（SeO3） 2 and [（VO）（H2O）（SeO3）2]2（HaEDD） 3 （EDD = N1,N1′-（ethane-1,2-diyl）diethane-1,2-diamine） were hydrothermally synthesized, and characterized with elemental analysis, FT-IR spectrum, Raman spectrum, TG-DTA analysis, EPR spectra, and single-crystal X-ray diffraction analysis. Compound I belongs to the triclinic system, space group P1^- with a = 7.7527（5）, b = 9.5345（10）, c = 9.8192（8） A^°, α = 92.712（3）, β = 105.540（3）, γ = 108.154（4）°, V = 657.66（1） A^°^3, Mr = 782.22, Z = 1, F（000） = 384,μ（MoKa） = 3.544 mm^-1, R = 0.0432 and wR = 0.1142; Compound 2 is of orthorhombic system, space group F212121 with a = 7.6574（15）, b = 14.916（3）, c = 19.085（4） A, V = 2179.8（8） Aa, Mr = 605.21, Z = 4, F（000） = 1200, μ（MoKa） = 2.579 mm^-1, R = 0.0338 and wR = 0.0658; Compound 3 belongs to the triclinic system, space group P1^- with a = 9.247（2）, b = 9.659（2）, c = 7.2651（19） A^°, α = 98.171（7）, β = 103.709（5）, γ = 114.712（13）°, V = 550.9（2） A^°^3, Mr = 828.03, Z = 1, F（000） = 400, μ（MoKa） = 7.537 mm^-1, R = 0.0641 and wR = 0.2118. Compound 1 is constructed from alternating corner-shared [VO4N2] octahedra and SeO3H units, forming a dimeric vanadium unit. These assemblies are further linked into an infinite chain via hydrogen bonds along the a axis. In the structure of 2, two distinct V centers form centrosymmetric [V2O6N4] clusters through edge-sharing, and the SeO3 unit serves as a capping unit to fix the oxovanadate cluster. In the structure of 3, each [VO6] octahedron shares four oxygen atoms with adjacent Se atoms, while every SeO3 unit shares two oxygen atoms with neighboring V atoms. This connectivity of alternating VO6 and SeO3 units results in a joint-like chain. Based on the TGA analysis, these three compounds are thermally stable under 200℃ .

Mechanistic research:Selenium regulates virulence factors,reducing adhesion ability and inflammatory damage of Helicobacter pylori

BACKGROUND The pathogenicity of Helicobacter pylori is dependent on factors including the environment and the host.Although selenium is closely related to pathogenicity as an environmental factor,the specific correlation between them remains unclear.AIM To investigate how selenium acts on virulence factors and reduces their toxicity.METHODS H.pylori strains were induced by sodium selenite.The expression of cytotoxin-associated protein A(CagA)and vacuolating cytotoxin gene A(VacA)was determined by quantitative PCR and Western blotting.Transcriptomics was used to analyze CagA,CagM,CagE,Cag1,Cag3,and CagT.C57BL/6A mice were infected with the attenuated strains subjected to sodium selenite induction,and H.pylori colonization,inflammatory reactions,and the cell adhesion ability of H.pylori were assessed.RESULTS CagA and VacA expression was upregulated at first and then downregulated in the H.pylori strains after sodium selenite treatment.Their expression was significantly and steadily downregulated after the 5th cycle(10 d).Transcriptome analysis revealed that sodium selenite altered the levels affect H.pylori virulence factors such as CagA,CagM,CagE,Cag1,Cag3,and CagT.Of these factors,CagM and CagE expression was continuously downregulated and further downregulated after 2 h of induction with sodium selenite.Moreover,CagT expression was upregulated before the 3rd cycle(6 d)and significantly downregulated after the 5th cycle.Cag1 and Cag3 expression was upregulated and downregulated,respectively,but no significant change was observed by the 5th cycle.C57BL/6A mice were infected with the attenuated strains subjected to sodium selenite induction.The extent of H.pylori colonization in the stomach increased;however,sodium selenite also induced a mild inflammatory reaction in the gastric mucosa of H.pylori-infected mice,and the cell adhesion ability of H.pylori was significantly weakened.CONCLUSION These results demonstrate that H.pylori displayed virulence attenuation after the 10th d of sodium selenite treatment.Sodium selenite is a low toxicity compound with strong stability that can reduce the cell adhesion ability of H.pylori,thus mitigating the inflammatory damage to the gastric mucosa.

BoMyrosinase plays an essential role in sulforaphane accumulation in response to selenite treatment in broccoli

Sulforaphane, a naturally specialized metabolite, plays significant roles in human disease prevention and plant defense. Myrosinase(MY) is a key gene responsible for the catalysis of sulforaphane formation, but the molecular mechanisms through which MY regulates sulforaphane biosynthesis in plants remains largely unknown. Here, we discovered that the change of sulforaphane content in broccoli sprouts caused by exogenous selenite treatments is positively related to BoMY expression. BoMY overexpression in the Arabidopsis thaliana tgg1 mutants could dramatically increase myrosinase activity and sulforaphane content in the rosette leaves of 35S::BoMY/tgg1 and rescue its phenotypes.Moreover, an obvious increase of myrosinase activity and sulforaphane content was displayed in transgenic BoMY-overexpressed broccoli lines.In addition, a 2 033 bp promoter fragment of BoMY was isolated. Yeast one-hybrid(Y1H) library screening experiment uncovered that one bHLH transcription factor, BoFAMA, could directly bind to BoMY promoter to activate its expression, which was further evidenced by Y1H assay and dual-luciferase reporter assay. BoFAMA is a selenite-responsive transcription factor that is highly expressed in broccoli leaves;its protein is solely localized to nucleus. Additionally, genetic evidence suggested that the knockdown of FAMA gene in Arabidopsis thaliana could significantly decrease sulforaphane yield by inhibiting the expression of myrosinase genes. Interestingly, exogenous selenite supply could partially restore the low level of sulforaphane content in transgenic Arabidopsis FAMA-silencing plants. Our findings uncover a novel function of FAMAMY module in the regulation of selenite-mediated sulforaphane synthesis and provide a new insights into the molecular mechanism by which selenite regulates the accumulation of sulforaphane in plants.

黄鳝的人工密养

黄鳝的人工密养人工养殖黄鳝；增大密度是提高单位面积产量和经济效益的重要措施，一般每平方米可放养２５克左右的幼鳝６０尾。饲养管理要点归纳如下：一、合理投喂饲料黄鳝是以动物性饲料为主的杂食性鱼类。在人工饲养的条件下，对饵料的适应性较广，可投喂小杂鱼、小虾...

Sodium selenite promotes neurological function recovery after spinal cord injury by inhibiting ferroptosis

Ferroptosis is a recently discovered form of iron-dependent cell death,which occurs during the pathological process of various central nervous system diseases or injuries,including secondary spinal cord injury.Selenium has been shown to promote neurological function recovery after cerebral hemorrhage by inhibiting ferroptosis.However,whether selenium can promote neurological function recovery after spinal cord injury as well as the underlying mechanism remain poorly understood.In this study,we injected sodium selenite(3μL,2.5μM)into the injury site of a rat model of T10 vertebral contusion injury 10 minutes after spinal cord injury modeling.We found that sodium selenite treatment greatly decreased iron concentration and levels of the lipid peroxidation products malondialdehyde and 4-hydroxynonenal.Furthermore,sodium selenite increased the protein and mRNA expression of specificity protein 1 and glutathione peroxidase 4,promoted the survival of neurons and oligodendrocytes,inhibited the proliferation of astrocytes,and promoted the recovery of locomotive function of rats with spinal cord injury.These findings suggest that sodium selenite can improve the locomotive function of rats with spinal cord injury possibly through the inhibition of ferroptosis via the specificity protein 1/glutathione peroxidase 4 pathway.

Redifferentiation of Human Gastric Cancer Cells Induced by Ascorbic Acid and Sodium Selenite

Objective To explore the effects and mechanisms of ascorbic acid (AA) and sodium selenite (SS) on growth inhibition and redifferentiation in human gastric cancer cells. Methods In the present study, trypan blue dye exclusion method was used to determine the cell growth curve and mitotic index, cell electrophoresis and colonogenic potential were used as the indexes of redifferentiation. In order to find out the mechanisms of redifferentiation, the activities of superoxide dismutase (SOD), glutathione peroxidase (GPX) and catalase (CAT) were assayed, the content of malondialdehyde (MDA), reduced glutathione (GSH) and H2O2 were evaluated. Results After treatment with AA 3 mol/L + SS 2μmol/L, the growth rate and mitotic index of human gastric cancer cells (MGc-803) decreased remarkably. The indexes related with cell malignancy were alleviated. For example, cell surface charge was obviously decreased, the electrophoresis rate was dropped from 2.21 to 1.15μm·s-1·V-1·cm-1. The indexes related with cell redifferentiation were promoted. For example, the colonogenic potential was decreased to 93.5%. These results indicated that redifferentiation of human gastric cancer cells was successfully induced by AA + SS. The activities of SOD and GPX were significantly higher, while the activity of CAT was slower in treated group than that in the control. The content of MDA was slightly decreased, GSH was sharply decreased, and H2O2 content was dramatically increased. Conclusion These results indicated that combination of ascorbic acid and sodium selenite may induce the redifferentiation of human gastric cancer cells and inhibit cell growth by virtue of enhancing the activities of antioxidative enzymes and inducing the formation of H2O2, and altering the cell redox status. Combination of ascorbic acid and sodium selenite may be a potent anticancer agent for human gastric cancer.

Sodium selenite ameliorates dextran sulfate sodiuminduced chronic colitis in mice by decreasing Th1, Th17, and γδT and increasing CD4(+)CD25(+) regulatory T-cell responses

AIM To assess the effect of sodium selenite on the severity of dextran sulfate sodium(DSS)-induced colitis in C57BL/6 mice.METHODS Mice were randomly divided into four groups(n = 10/group): normal group, selenium(Se) group, chronic colitis group, and Se + chronic colitis group. The mice were sacrificed on day 26. Survival rates, clinical symptoms, colon length, and histological changes were determined. The percentages and absolute numbers of immune system cells in the lamina propria lymphocytes(LPL) of the colon, the expression of m RNA in colon tissue, and the concentrations of Th1, Th17, and Treg cytokines in LPL from the large intestine, were measured.RESULTS Se significantly ameliorated the symptoms of colitis and histological injury(P < 0.05 each), increasing the proportions of neutrophils and CD4+ CD25+ T cells(P < 0.05 each) and decreasing the proportions of γδT cells, CD4+, CD4+CD44+, and CD4+ CD69+ T cells in LPL(P < 0.05 each). Moreover, Se reduced the expression of IL-6, IFN-γ, IL-17 A, IL-21, T-bet, and RORγt(P < 0.05 each), but enhanced the expression of IL-10 and Foxp3(P < 0.05 each). CONCLUSION These results suggest that Se protects against DSSinduced chronic colitis perhaps by increasing the number of CD4(+)CD25(+) Tregs that suppress the secretion of proinflammatory cytokines and populations of Th1, Th17, and γδT cells.

Biochemical and cellular evidence of the benefit of a combination of cerium oxide nanoparticles and selenium to diabetic rats

AIM: To study the combinative effects of nanocerium and selenium in a murine model of diabetes. METHODS: Cerium oxide (CeO2) nanoparticles (60 mg/kg per day) and sodium selenite (5 μmol/kg per day) aloneor in combination, or the metal form of CeO2 (60 mg/kg) were administered for 2 wk by intraperitoneal injection to streptozotocin-induced diabetic rats. At the end of treatment blood was collected, liver tissue dissected and then oxidative stress markers, extent of energy depletion and lipid prof ile were evaluated.RESULTS: Antioxidant enzymes and high density lipoprotein decreased whereas oxidative stress, adenosine diphosphate/adenosine triphospahte levels, cholesterol, triglyceride and low density lipoprotein increased on induction of diabetes. All were improved by a combination of nanocerium and sodium selenite. There was a relative amelioration by CeO2 nanoparticles or sodium selenite alone, but the metal form of CeO2 showed no signif icant improvement. CONCLUSION: The combination of nanocerium and sodium selenite is more effective than either alone in improving diabetes-induced oxidative stress.

Hydrothermal Synthesis and Crystal Structure of a Novel Selenite-chloride:[Cd_4(SeO_3)_2Cl_4(H_2O)]_n with a Three-dimensional Framework

A novel three-dimensional（3-D） compound [Cd4（SeO3）2Cl4（H2O）]n（1） was prepared from a hydrothermal reaction and structurally characterized.Compound 1 crystallizes in the space group Fmmm of the orthorhombic system with eight formula units in a cell：a = 15.5165（4）,b = 17.5090（9）,c = 7.3318（5） ,V = 1991.9（2） 3,Cd4Cl4H2O7Se2,Mr = 863.38,Dc = 5.758 g/cm3,S = 1.075,μ（MoKα） = 16.820 mm-1,F（000） = 3088,R = 0.0427 and wR = 0.1220.Compound 1 features a 3-D structure with the cadmium atoms having two different coordination environments,i.e.,six-and eight-coordination geometries.Two different chain-like structures of cadmium-oxo polyhedra are interconnect to each other to give a 2-D layer of [Cd4（SeO3）2（H2O）]n4n＋.Between the [Cd4（SeO3）2（H2O）]n4n＋ layers is a novel chloride layer.A 3-D framework is constructed from these [Cd4（SeO3）2（H2O）]n4n＋ layers linked by the chloride layers.

Comparison of the impact of epigallocatechin gallate and ellagic acid in an experimental cataract model induced by sodium selenite

AIM：To compare the potential protective effects of epigallocatechin gallate（EGCG） and ellagic acid（EA） in an experimental cataract model.●METHODS：Twenty-eight Spraque-Dawley rat pups were assigned into four groups.All the rats,except for those in the control group,were injected subcutaneously sodium selenite to induce experimental cataract on the postpartum ninth day,and between 10 th and 14 th days.Rats in the sham,EGCG,and EA groups were intraperitoneally administered 50 mg/（kg·d） saline solution,50 mg/（kg·d） EGCG and 200 mg/（kg·d） EA,respectively.The reduced glutathione（GSH） and malondialdehyde（MDA） levels,total antioxidant status（TAS） and total oxidant status（TOS） in lens supernatants were measured.RESULTS：The mean cataract gradings in EGCG and EA groups were found to be significantly lower than that in sham group（P〈0.001）.The mean GSH levels and TASs in EGCG and EA groups were significantly higher than that in sham group while mean MDA levels and TOSs in EGCG and EA groups were significantly lower than that in the sham group（P〈0.001）.CONCLUSION：EGCG and EA have protective effects on cataract development via the inhibition of oxidative stress.

A study on Se application for improving the soil in the environment at lower Se level

A result that application of sodium selenite or fly ash to some of soilin loess plateau can increase Se content in wheat grain has been demonstrated by the pot and field experiments, and added Se in soil can last its availability for 3 years. So this is a good measure for improving the low Se soils and preventing the Kaschin-Beck disease.

STUDY ON BIOLOGICAL ACTIVITY OF SELENIUM-ENRICHED MUSSEL EXTRACT

In this study on the biological activity of selenium-enriched mussel extract. rdts were randomly separated into three weight groups fed a basal selenium-deficient diet. diet supplemented by selenium from sodium selenite. and selenium enriched mussel extract. aspectively. Body weights of the rats were determined and metabolic experiment Was conducted after 4 weeks. The rats were killed after 8 weeks. Glutathione peroxidase activity and selenium content in liver and blood were determined. The results showed that selenium in mussel extract could be better absorbed by the rats and effectively promote their growth.There were no significant differences in glutathione peroxidase activity between the rats fed mussel extract or sodium selenite. Compared with sodium selenite group. the selenium content in blood and liver was significantly higher in the rats fed mussel extract.

Effects of selenium on electrophysiological changes associated with diabetic peripheral neuropathy

Our previous study has demonstrated that sodium selenite prevents oxidative stress, suggesting that selenium can improve diabetic peripheral neuropathy. Results from this study demonstrated that diabetes mellitus resulted in significant increased time to peak, as well as rheobase and chronaxie values. In addition, maximum depolarization, area under compound action potential, kinetics, and conduction velocities of fast and slow nerve fiber groups were decreased. Sodium selenite exhibited positive effects on alterations of diabetes mellitus-induced conduction velocity distribution. This neuroprotective effect was primarily observed in the area under compound action potential and compound action potential kinetic waveforms, as well as rheobase and chronaxie. Results from this study showed that selenium supplementation blocked the diabetes mellitus-induced shift of actively contributing nerve fibers, and restored levels towards age-matched control group values. Chronic selenate supplementation for experimental diabetic peripheral neuropathy exhibited protective effects in measured electrophysiological parameters.

Alabaster and Selenite Gypsum:I-Dehydration-Rehydration Comparison Studies

Two types of gypsum raw materials, selenite and alabaster, were used to prepare dental stone (a-hemihydrate). Gypsum lumps (0.8~2.5 cm) were hydrothermally treated at 135, 160 and 180癈 for 6, 2 and 1 h respectively. The physicochemical properties and composition characteristics of the a-hemihydrates prepared from selenite and alabaster raw gypsum were determined. The results indicated that both the selenite and alabaster raw gypsum show the same chemical and mineralogical composition of calcium sulphate dihydrate. They differs only in their microstructure, selenite raw gypsum exhibits perfect regular crystals while alabaster gypsum, on the other hand, exhibits irregular, large size and interlocked crystals. Selenite is more accessible to dehydration than alabaster raw gypsum. The a-hemihydrate samples prepared from alabaster raw gypsum showed a very short setting time and a lower compressive strength values in relation to that prepared from selenite gypsum. The compressive strength values of the all prepared samples were higher than that specified by A.D.A specification for dental use. To optimize the setting time of both products further studies are needed.

Protective Role of C-Phycocyanin Against Secondary Changes During Sodium Selenite Mediated Cataractogenesis

Age related cataract is the leading cause of blindness associated with accumulation of oxidative stress in the eye lens.The present investigation reveals the rational of the beneficial effects of the natural compound C-phycocyanin(CPC)is beneficial when administered to rat pups to protect against the secondary effects of sodium selenite induced cataractogenesis.A single subcutaneous dose of sodium selenite(19 lmol/kg body weight)on the 10th day of postpartum is adequate to induce cataract in rat pups.Serum biochemical parameters,such as the level of electrolytes,mean activities of anti-oxidant enzymes i.e.superoxide dismutase,catalase and reduced glutathione were observed to be significantly altered during selenite induced cataractogenic process.Histopathological examination revealed signs of degradation of normal cell architecture in the liver,kidney and eye lens.Interestingly,the deleterious effects of sodium selenite toxicity were restored with the simultaneous treatment with C-PC.The results suggest that an administration of 200 mg/kg body weight of C-PC has the ability to prevent/alter the secondary changes reflected in the serum biochemical and histological modifications in rats exposed to sodium selenite.These results complement the beneficial role of C-PC of cyanobacterial origin as a efficacious anti-cataractogenic agent against sodium selenite toxicity.

Recent Developments to Mitigate Selenium Deficiency in Agricultural Eco-Systems

Under changing climate,trace elements like selenium(Se)have emerged as vital constituent of agro-ecosystems enabling crop plants to off-set the adverse effects of suboptimal growth conditions.The available form of selenium is important for boosting its bioavailability to crop plants having varied agro-botanical traits and root architectural systems.As compared to selenite,the selenate has a weaker soil bonding,higher absorption in the soil solution which results in a comparatively absorption by plant roots.Various factors including dry climate,high pH,optimal ambient air temperature,less accumulation of water,and low concentration of organic matter in the soil tend to boost the selenate ratio in the soil.The use of selenium pelleted seeds has emerged as an interesting and viable alternative to alleviate selenium deficiency in agricultural eco-systems.Similarly,the co-inoculation of a mixture of Selenobacteria and Arbuscular mycorrhizal fungi represents an evolving promising strategy for the bio-fortification of wheat plants to produce selenium-rich flour to supplement human dietary needs.Furthermore,in-depth research is required to assure the effectiveness of biological fertilization procedures in field conditions as well as to explore and increase our understanding pertaining to the underlying main mechanisms and channels of selenium absorption in plants.The focus of this review is to synthesize the recent developments on Se dynamics in soil-plant systems and emerging promising strategies to optimize its levels for crop plants.Recent developments regarding the use of micro-organisms as a biotechnological mean to enhance plant nutrition and crop quality have been objectively elaborated.The study becomes even more pertinent for arid and semi-arid agro-ecosystems owing to the potential role of selenium in providing stress tolerance to crop plants.Moreover,this review synthesizes and summarizes the recent developments on climate change and bioavailability,and the protective role of selenium in crop plants.

SLENIUM FROM BEEF IS HIGHLY BIOAVAILABLE AS ASSESSED BY LIVER GLUTATHIONE PEROXIDASE （EC1．11．1．9） ACTIVITY AND TISSUE SELENI

The bioavailability of selenium(Se)from ground beef has been previously found in this laboratory to be greater than that of selenite or selenate when fed to female Fischer 344 rats(B. Shi,J.E.Spallholz,J Am Coil Nutr,13:95￣101,1994).In the present study we examined the bioavailability of Se from various commercial portions of beef,the liver,striploin,round, shoulder and brisket.All beef was cooked, freeze-dried,finely powdered and mixed with the other dietary ingredients.The experimental diets were fed to the weanling Fischer 344 rats which had been subjected to dietary depletion of Se for 6 weeks.The bioavailability of Se from the beef diets was compared with that of Se as se lenite or L-seienomethionine(SeMet)added to torula-yeast diets.Each experimental diet contained 0'10mg Se/kg.After 8 weeks of dietary Se repletion,relative activity of liver glutathione peroxidase (EC 1.11.1.9;GSHPx) from the different dietary groups colllpared with that of control animals(100%)was(%):selenite 91,SeMet 122 (P<0.05),liver 108, striploin 105,round 106, shoulder 106,brisket 103.Se recovery in liver was generally highest from SeMet>beef muscle=beef liver>selenite.Muscle tissue deposition of Se was highest from SeMet>beef muscle>selenite=beef liver.In addition, the feeal excretion of Se was lowest from the SeMet dietary group and highest from the selenite dietary group.The experimetal results suggest that all cuts of beef appear to be highly bioavailable sources of dietary Se when compared with selenite or L-SeMet.

Analysis of Protein Characteristics of Selenite Transporter OsPT2 in Rice

OsPT2,which is a selenite transporter in rice,belongs to rice phosphate transporter family OsPT. In this study,the amino acid sequence information of OsPT family members was collected using NCBI database. Bioinformatics method was employed to analyze physical and chemical properties and protein structure of OsPT2 and its homologous relationship with other members of the family. The results indicated that OsPT2 was a stable alkaline hydrophobic protein embedded in the cell membrane. The protein contained 11 transmembrane domains,and consisted of 45. 08% of alpha helix,16. 48% of extended strand,10. 80% of beta turn and 27. 65% of random coil,forming a barrel-like three-dimensional structure. Members in OsPT family had high homology and could be divided into 5 subgroups.OsP T2 had closer relationship with OsPT1 and OsPT3. This study could provide a basis for further revealing of molecular mechanism of selenite transport in rice.

Sodium selenite may be not the optimal speciation as an effective therapy for arsenic-induced anxiety-/depression-like behavior

Major depressive disorder is a serious and prevalent neuropsychiatric disorder,affecting more than 350 million people worldwide.Here,sodium selenite(SS)was selected as the selenite supplement to improve the behavior in a mouse model of depression induced by As.SS may be not the optimal speciation for selenite supplementation and the source of the SS used in the study was not disclosed.There are many mouse models of depression and anxiety;however,in the current study,a classical mouse model of depression was not used.Thus,several questions still need to be further discussed.Taken together,the results indicate that SS may be not the optimal speciation as an effective therapy for As-induced anxiety-/depression-like behavior.