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1.
Sci Rep ; 9(1): 18752, 2019 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-31822702

RESUMO

Obesity is often accompanied by dyslipidemia, high blood glucose, hypertension, atherosclerosis, and myocardial dysfunction. Selenate is a vital antioxidant in the cardiovascular system. The beneficial effects of selenate on obesity-associated cardiac dysfunction and potential molecular mechanism were identified in both H9C2 cells and C57BL/6J mice hearts. The cardiac histological preformation in C57BL/6J mice were evaluated by cross-sectional area (CSA) of cardiomyocytes and percent area of fibrosis in the left ventricles. The cardiac autophagy flux in H9C2 cells and C57BL/6J mice hearts was analyzed by Western blots and the number of autophagosomes and autolysosome in H9C2 cells. In the present study, we found that lipid overload caused increases in serum lipid, CSA, and percent area of fibrosis. We further found that lipid-induced accumulation of autophagosomes  was due to depressed autophagy degradation, which was not restored in the pretreatment with 3-methyladenine and chloroquine, whereas, it was improved by rapamycin. Moreover, we demonstrated that increased levels of serum lipid, CSA, percent area of fibrosis and mRNA expression related to cardiomyocytes hypertrophy and fibrosis were significantly reduced after selenate treatments of mice. We also found selenate treatment significantly down-regulated activity of the Akt pathway, which was activated in response to lipid-overload. Furthermore, selenate dramatically improved cardiac autophagic degradation which was suppressed after exposure to lipid-overload in both H9C2 cells and C57BL/6J mice hearts. Taken together, selenate offers therapeutic intervention in lipid-related metabolic disorders, and protection against cardiac remodeling, likely through regulation of the activity of autophagic degradation and Akt pathway.


Assuntos
Antioxidantes/administração & dosagem , Autofagia/efeitos dos fármacos , Cardiomiopatias/tratamento farmacológico , Ácido Selênico/administração & dosagem , Remodelação Ventricular/efeitos dos fármacos , Animais , Autofagossomos/efeitos dos fármacos , Autofagossomos/metabolismo , Cardiomiopatias/sangue , Cardiomiopatias/etiologia , Cardiomiopatias/metabolismo , Linhagem Celular , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Feminino , Fibrose , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/patologia , Humanos , Metabolismo dos Lipídeos , Lipídeos/sangue , Masculino , Camundongos , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia , Obesidade/sangue , Obesidade/etiologia , Obesidade/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Transdução de Sinais/efeitos dos fármacos
2.
BMC Plant Biol ; 19(1): 502, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31730480

RESUMO

BACKGROUND: Selenium (Se) is a beneficial element for higher plants and essential for mammals. To study the effect of the foliar application of sodium selenate on fragrant rice performance, a pot experiment was conducted in Guangdong, China. At the initial heading stage, one-time foliar application of sodium selenate with concentrations of 0, 10, 20, 30, 40 and 50 µmol·L- 1 (named CK, Se1, Se2, Se3, Se4 and Se5, respectively) were foliar applied on two fragrant rice varieties, 'Meixiangzhan-2' and 'Xiangyaxiangzhan'. RESULTS: Selenate application at the initial heading stage not only improved the grain yield of fragrant rice by increasing the seed-setting rate and grain weight, but also promoted the grain quality by increasing crude protein contents and lowering the chalky rice rate. Furthermore, Se applications enhanced the biosynthesis of 2-acetyl-1- pyrroline (2-AP), the main aromatic compound, by increasing the contents of precursors (△1- pyrroline, proline and pyrroline-5-carboxylic acid (P5C)) and the activities of enzymes (proline dehydrogenase (PRODH), △1-pyrroline-5-carboxylic acid synthetase (P5CS), and ornithine aminotransferase (OAT)) in fragrant rice. The results also showed that foliar application of sodium selenate enhanced the antioxidant system of both varieties by promoting the activities of peroxidase (POD), superoxide dismutase (SOD), catalase (CAT) and reducing the contents of malondialdehyde (MDA). Furthermore, the real-time PCR analyses depicted that foliar application of selenate up-regulated the GPX1, GPX4 and CATC transcripts. The higher antioxidative enzymatic activities might strength the stress resistant to ensure the stability of yield in fragrant rice form abiotic stress. CONCLUSIONS: Foliar applications of sodium selenate at the initial heading stage increased the grain 2-AP content by enhancing the biosynthesis-related enzymes and precursors. The grain yield and quality of fragrant rice also increased due to selenate application. Furthermore, foliar application of selenate promoted the activities of enzymes such as POD, SOD and CAT and up-regulated the expression of gene GPX4, GPX1 and CATC.


Assuntos
Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Oryza/efeitos dos fármacos , Pirróis/metabolismo , Ácido Selênico/administração & dosagem , Antioxidantes/metabolismo , Biomassa , Catalase/metabolismo , Grão Comestível/efeitos dos fármacos , Grão Comestível/enzimologia , Grão Comestível/genética , Grão Comestível/crescimento & desenvolvimento , Malondialdeído/metabolismo , Oryza/enzimologia , Oryza/genética , Oryza/crescimento & desenvolvimento , Peroxidases/metabolismo , Proteínas de Plantas/metabolismo , Prolina/metabolismo , Superóxido Dismutase/metabolismo
3.
Neurotherapeutics ; 16(1): 192-202, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30215171

RESUMO

Insufficient supply of selenium to antioxidant enzymes in the brain may contribute to Alzheimer's disease (AD) pathophysiology; therefore, oral supplementation may potentially slow neurodegeneration. We examined selenium and selenoproteins in serum and cerebrospinal fluid (CSF) from a dual-dose 24-week randomized controlled trial of sodium selenate in AD patients, to assess tolerability, and efficacy of selenate in modulating selenium concentration in the central nervous system (CNS). A pilot study of 40 AD cases was randomized to placebo, nutritional (0.32 mg sodium selenate, 3 times daily), or supranutritional (10 mg, 3 times daily) groups. We measured total selenium, selenoproteins, and inorganic selenium levels, in serum and CSF, and compared against cognitive outcomes. Supranutritional selenium supplementation was well tolerated and yielded a significant (p < 0.001) but variable (95% CI = 13.4-24.8 µg/L) increase in CSF selenium, distributed across selenoproteins and inorganic species. Reclassifying subjects as either responsive or non-responsive based on elevation in CSF selenium concentrations revealed that responsive group did not deteriorate in Mini-Mental Status Examination (MMSE) as non-responsive group (p = 0.03). Pooled analysis of all samples revealed that CSF selenium could predict change in MMSE performance (Spearman's rho = 0.403; p = 0.023). High-dose sodium selenate supplementation is well tolerated and can modulate CNS selenium concentration, although individual variation in selenium metabolism must be considered to optimize potential benefits in AD. The Vel002 study is listed on the Australian and New Zealand Clinical Trials Registry ( http://www.anzctr.org.au /), ID: ACTRN12611001200976.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Antioxidantes , Ácido Selênico , Selênio , Oligoelementos , Idoso , Doença de Alzheimer/sangue , Doença de Alzheimer/líquido cefalorraquidiano , Antioxidantes/administração & dosagem , Antioxidantes/metabolismo , Sistema Nervoso Central/efeitos dos fármacos , Sistema Nervoso Central/metabolismo , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Ácido Selênico/administração & dosagem , Ácido Selênico/sangue , Ácido Selênico/líquido cefalorraquidiano , Selênio/administração & dosagem , Selênio/sangue , Selênio/líquido cefalorraquidiano , Oligoelementos/administração & dosagem , Oligoelementos/sangue , Oligoelementos/líquido cefalorraquidiano
4.
Sci Rep ; 8(1): 16234, 2018 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-30390003

RESUMO

Usnic acid (UA), a lichen secondary substance, has considerable anticancer activity in vitro, whereas its effect in vivo is limited. Here, potassium usnate (KU) was prepared by the salinization of UA to enhance its water solubility. KU showed increased bioavailability compared with UA in the tumor, liver, and plasma of a CT26 syngeneic mouse tumor xenograft model after oral administration, as determined by LC-MS/MS analysis. KU exhibited potent anticancer effects on colorectal cancer cells and inhibited liver metastasis in an orthotopic murine colorectal cancer model. KU treatment downregulated the epithelial-mesenchymal markers Twist, Snail, and Slug and the metastasis-related genes CAPN1, CDC42, CFL1, IGF1, WASF1, and WASL in cells and tumor tissues. The present results suggest the potential application of the water-soluble form of UA, KU, in anticancer therapy.


Assuntos
Antineoplásicos/administração & dosagem , Benzofuranos/administração & dosagem , Neoplasias Colorretais/tratamento farmacológico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Ácido Selênico/farmacocinética , Administração Oral , Animais , Antineoplásicos/química , Antineoplásicos/farmacocinética , Benzofuranos/química , Benzofuranos/farmacocinética , Disponibilidade Biológica , Linhagem Celular Tumoral/transplante , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Modelos Animais de Doenças , Ensaios de Seleção de Medicamentos Antitumorais , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Humanos , Masculino , Camundongos , Invasividade Neoplásica/patologia , Invasividade Neoplásica/prevenção & controle , Potássio/química , Ácido Selênico/administração & dosagem , Resultado do Tratamento
5.
J Neurosci Res ; 96(11): 1798-1815, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30054946

RESUMO

Selenium (Se) deficiency is believed to be involved in pathogenesis of Alzheimer's disease (AD) due to failure of antioxidant system. Its supplementation may restore the antioxidant system and compensate the impairments caused by AD. Present study reveals the effect of Se on the proteomic changes in cortex within triple transgenic male AD mice (3 × Tg-AD) after 4 months sodium selenate supplementation. Using iTRAQ comparative proteomics approach, 142 proteins found significant alterations with 96 down-regulated and 46 up-regulated proteins in the cortices of AD mice in comparison with the wild non-transgenic type mice. On treatment with sodium selenate, 41 proteins showed reverse expression, that is, thirty three proteins were down-regulated in AD mice but up-regulated in selenate treated AD mice while eight up-regulated proteins in AD mice showed lower expression in selenate treated mice. OmicsBean bioinformatics analysis revealed that Se positively affected the proteins vital in biological process, structural cores, and molecular functions, which include metabolic proteins, structural proteins, signaling molecules, oxidative stress balancers, and proteosomal degradation proteins. Results of mass spectrometry (MS) were further confirmed by Western blot analysis of five important proteins, prompting the authenticity of the MS results. This paper fills the protein-based molecular gap between AD and Se-treatment, and it provides a full view of Se in reversing the change of cortical protein levels during AD formation.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Antioxidantes/farmacologia , Córtex Cerebral/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Proteínas/metabolismo , Selênio/farmacologia , Animais , Modelos Animais de Doenças , Ontologia Genética , Masculino , Espectrometria de Massas , Camundongos , Camundongos Transgênicos , Proteínas/genética , Proteômica/métodos , Ácido Selênico/administração & dosagem
6.
Meat Sci ; 143: 230-236, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29803133

RESUMO

Sixty New Zealand White weaned rabbits were divided into three groups and subjected to different dietary treatments: a standard diet for the control (C), a standard feed supplemented with 10% of plain olive leaves (OL) and a standard feed supplemented with 10% of selenium-fortified olive leaves (100 mg/L of foliar spray sodium selenate solution; SeOL). The productive performance was recorded at the time of slaughter (after 35 days); the carcass and meat traits were determined and estimated indexes of fatty acid metabolism were calculated. No significant differences were found on the rabbit productive performance and the physical-chemical characteristics of the meat. Both group of rabbits on the enriched diet showed leaner and thinner carcasses and a higher meat concentration of oleic acid. The estimated index of Δ5 + Δ6-desaturase, starting from n-6 fatty acids, was lower in both groups supplemented with leaves. The use of selenium-fortified olive leaves, positively affected the lipid oxidative stability of rabbit meat.


Assuntos
Ração Animal , Ácidos Graxos Insaturados/metabolismo , Carne/análise , Desenvolvimento Muscular , Olea/química , Folhas de Planta/química , Ácido Selênico/administração & dosagem , Aerossóis , Agricultura/economia , Algoritmos , Ração Animal/economia , Animais , Biofortificação , Feminino , Qualidade dos Alimentos , Humanos , Resíduos Industriais/análise , Resíduos Industriais/economia , Itália , Masculino , Carne/economia , Músculo Esquelético/crescimento & desenvolvimento , Músculo Esquelético/metabolismo , Valor Nutritivo , Olea/crescimento & desenvolvimento , Olea/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Coelhos , Ácido Selênico/metabolismo , Aumento de Peso
7.
ACS Chem Neurosci ; 9(7): 1637-1651, 2018 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-29641182

RESUMO

Selenium (Se), an antioxidant trace element, is an important nutrient for maintaining brain functions and is reported to be involved in Alzheimer's disease (AD) pathologies. The present study has been designed to elucidate the protein changes in hippocampus of 3×Tg-AD mice after supplementing sodium selenate as an inorganic source of selenium. By using iTRAQ proteomics technology, 113 differentially expressed proteins (DEPs) are found in AD/WT mice with 37 upregulated and 76 downregulated proteins. Similarly, in selenate-treated 3×Tg-AD (ADSe/AD) mice, 115 DEPs are found with 98 upregulated and 17 downregulated proteins. The third group of mice (ADSe/WT) showed 75 DEPs with 46 upregulated and 29 downregulated proteins. Among these results, 42 proteins (40 downregulated and 2 upregulated) in the diseased group showed reverse expression when treated with selenate. These DEPs are analyzed with different bioinformatics tools and are found associated with various AD pathologies and pathways. Based on their functions, selenate-reversed proteins are classified as structural proteins, metabolic proteins, calcium regulating proteins, synaptic proteins, signaling proteins, stress related proteins, and transport proteins. Six altered AD associated proteins are successfully validated by Western blot analysis. This study shows that sodium selenate has a profound effect on the hippocampus of the triple transgenic AD mice. This might be established as an effective therapeutic agent after further investigation.


Assuntos
Doença de Alzheimer/metabolismo , Doença de Alzheimer/terapia , Antioxidantes/administração & dosagem , Hipocampo/metabolismo , Proteoma , Ácido Selênico/administração & dosagem , Animais , Modelos Animais de Doenças , Regulação da Expressão Gênica , Camundongos Transgênicos
8.
Anim Sci J ; 89(2): 298-306, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29034614

RESUMO

The objectives of the present study were to investigate the effects of selenium (Se) supplementation during in vitro maturation (IVM) on the developmental capacity of yak (Bos grunniens) oocytes. Nuclear maturation, DNA integrity, glutathione peroxidase (GSH-Px) activity, subsequent embryonic development, and gene expression after in vitro fertilization (IVF) were evaluated. The Se concentrations in yak plasma and follicular fluid were 0.142 and 0.069 µg/mL, respectively. The DNA damage in cumulus cells decreased significantly with 2 and 4 µg/mL supplementation of sodium selenite to IVM medium (P < 0.05). Total GSH-Px activity in oocytes increased in all Se supplementation groups, and the 2 and 4 µg/mL groups were significantly higher than the control group (0 µg/mL). However, the cleavage rate was not significantly different after Se supplementation (P > 0.05). The IVF blastocyst formation rates of 0, 1 and 4 µg/mL sodium selenite groups were 47.7%, 51.2% and 58.9%, respectively. The 2 µg/mL sodium selenite group had the highest blastocyst formation rate (60.5%). Gene expression analysis revealed that the quantity of transcripts associated with selenoprotein and protein synthesis were high in the 2 and 4 µg/mL groups. In conclusion, both GSH-Px activity of oocytes and DNA integrity of cumulus cells significantly increased with supplemental Se during oocyte IVM. Considering that embryonic development is responsive to Se supplementation, we inferred that appropriate Se concentrations during IVM were beneficial for yak oocyte maturation and subsequent development.


Assuntos
Desenvolvimento Embrionário/efeitos dos fármacos , Técnicas de Maturação in Vitro de Oócitos , Oócitos/crescimento & desenvolvimento , Ácido Selênico/administração & dosagem , Ácido Selênico/farmacologia , Animais , Blastocisto/efeitos dos fármacos , Bovinos , Dano ao DNA/efeitos dos fármacos , Fertilização in vitro , Expressão Gênica/efeitos dos fármacos , Glutationa Peroxidase/metabolismo , Oócitos/metabolismo , Ácido Selênico/metabolismo , Estimulação Química
9.
In Vitro Cell Dev Biol Anim ; 53(10): 940-953, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28940125

RESUMO

The effect of selenium deprivation and addition on the American eel brain endothelial cell line (eelB) was studied in three exposure media: complete growth medium (L15/FBS), serum-free medium (L15), and minimal medium (L15/ex). L15/ex contains only galactose and pyruvate and allowed the deprivation of selenium on cells to be studied. In L15/ex, without any obvious source of selenium, eelB cells survived for at least 7 d, formed capillary-like structures (CLS) on Matrigel, and migrated to heal wounds. Three selenium compounds were added to cultures: selenite, selenate, and selenomethionine (SeMet). Adding selenite or selenate to eelB cell cultures for 24 h caused dose-dependent declines in cell viability, regardless of the exposure media. Although varying with exposure media and viability end point, selenite was approximately 70-fold more cytotoxic than selenate. By contrast, 24 h exposures to either DL- or L-SeMet in the three media caused little or no cytotoxicity. However for 7 d exposures in L15/ex, DL- and L-SeMet were very cytotoxic, even at the lowest tested concentration of 31 µM. By contrast in L15 and L15/FBS, cytotoxicity was only observed with 500 and 1000 µM L-SeMet. In L15/FBS, eelB continued to migrate and form CLS in the presence of SeMet but at 500 µM, cell migration appeared stimulated. As judged from a colony-forming assay over 14 d in L15/FBS, 500 and 1000 µM DL- and L-SeMet inhibited cell proliferation. Overall, the responses of eel cells to selenium depended on the selenium form, concentration, and exposure media, with responses to SeMet being most dependent on exposure media.


Assuntos
Anguilla , Encéfalo/citologia , Meios de Cultura/farmacologia , Compostos de Selênio/farmacologia , Selênio/deficiência , Animais , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Meios de Cultura/química , Relação Dose-Resposta a Droga , Células Endoteliais , Neovascularização Fisiológica/efeitos dos fármacos , Ácido Selênico/administração & dosagem , Ácido Selênico/farmacologia , Ácido Selenioso/administração & dosagem , Ácido Selenioso/farmacologia , Selênio/farmacologia , Selenometionina/farmacologia
10.
Sci Rep ; 6: 39290, 2016 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-28008954

RESUMO

Many studies have shown that imbalance of mineral metabolism may play an important role in Alzheimer's disease (AD) progression. It was recently reported that selenium could reverse memory deficits in AD mouse model. We carried out multi-time-point ionome analysis to investigate the interactions among 15 elements in the brain by using a triple-transgenic mouse model of AD with/without high-dose sodium selenate supplementation. Except selenium, the majority of significantly changed elements showed a reduced level after 6-month selenate supplementation, especially iron whose levels were completely reversed to normal state at almost all examined time points. We then built the elemental correlation network for each time point. Significant and specific elemental correlations and correlation changes were identified, implying a highly complex and dynamic crosstalk between selenium and other elements during long-term supplementation with selenate. Finally, we measured the activities of two important anti-oxidative selenoenzymes, glutathione peroxidase and thioredoxin reductase, and found that they were remarkably increased in the cerebrum of selenate-treated mice, suggesting that selenoenzyme-mediated protection against oxidative stress might also be involved in the therapeutic effect of selenate in AD. Overall, this study should contribute to our understanding of the mechanism related to the potential use of selenate in AD treatment.


Assuntos
Doença de Alzheimer/patologia , Encéfalo/patologia , Íons/análise , Minerais/análise , Ácido Selênico/administração & dosagem , Animais , Antioxidantes/análise , Modelos Animais de Doenças , Glutationa Peroxidase/análise , Camundongos Transgênicos , Tiorredoxina Dissulfeto Redutase/análise
11.
PLoS One ; 11(4): e0152081, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27116220

RESUMO

Up to 1 billion people are affected by low intakes of the essential nutrient selenium (Se) due to low concentrations in crops. Biofortification of this micronutrient in plants is an attractive way of increasing dietary Se levels. We investigated a promising method of Se biofortification of rice seedlings, as rice is the primary staple for 3 billion people, but naturally contains low Se concentrations. We studied hydroponic Se uptake for 0-2500 ppb Se, potential phyto-toxicological effects of Se and the speciation of Se along the shoots and roots as a function of added Se species, concentrations and other nutrients supplied. We found that rice germinating directly in a Se environment increased plant-Se by factor 2-16, but that nutrient supplementation is required to prevent phyto-toxicity. XANES data showed that selenite uptake mainly resulted in the accumulation of organic Se in roots, but that selenate uptake resulted in accumulation of selenate in the higher part of the shoot, which is an essential requirement for Se to be transported to the grain. The amount of organic Se in the plant was positively correlated with applied Se concentration. Our results indicate that biofortification of seedlings with selenate is a successful method to increase Se levels in rice.


Assuntos
Oryza/metabolismo , Selênio/farmacocinética , Transporte Biológico Ativo , Germinação , Humanos , Hidroponia , Micronutrientes/administração & dosagem , Micronutrientes/farmacocinética , Micronutrientes/toxicidade , Oryza/efeitos dos fármacos , Oryza/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Plântula/metabolismo , Ácido Selênico/administração & dosagem , Ácido Selênico/farmacocinética , Ácido Selênico/toxicidade , Selênio/administração & dosagem , Selênio/toxicidade
12.
Arch Toxicol ; 90(1): 149-58, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25270623

RESUMO

An in vivo metabolism study in humans was carried out to investigate the toxicokinetics and metabolism of sodium selenate differentiating by the trimethylselenium (TMSe) status. Therefore, the changes in blood plasma concentration and the urinary excretion within 24 h of seven healthy subjects after oral administration of a dietary supplement containing sodium selenate (50 µg selenium) were analyzed. Three subjects belong to the subgroup of TMSe eliminators, and four subjects were related to the non-TMSe eliminators subgroup. The concentrations of total selenium in blood plasma and urine samples were determined by inductively coupled plasma-mass spectrometry (ICP-MS). Additionally, speciation analysis of urine samples was performed using ICP-MS coupled to a liquid chromatography system. Plasma selenium concentration changed from 82.5 ± 12.5 µg Se/L before to 85.1 ± 12.0 µg Se/L 2-3 h after supplementation. Considering the individual 24-hour background amounts of renal excreted selenium, the ingestion caused an additional excretion of 15.4 ± 3.3 µg Se/24 h (≙31.1 ± 7.6 % of the administered dose) with a maximum elimination already 2 h after exposure. The differentiated analysis revealed that in all subjects, the main elimination product (30.1 ± 6.9 % of the administered dose) was unmetabolized selenate. TMSe was only detected in the urine of the TMSe eliminators. This subgroup excreted in comparison with the non-TMSe eliminators a significantly lower amount of selenate. Only one subject metabolized selenate to a larger portion to methyl-2-acetamido-2-deoxy-1-seleno-ß-D-galactopyranoside (SeSug1) and methyl-2-amino-2-deoxy-1-seleno-ß-D-galactopyranoside (SeSug3). All other subjects showed only a minor metabolism of selenate to selenium-containing carbohydrates. By individuals, which do not excrete TMSe in urine basically, selenate is metabolized only marginally and is excreted rapidly via urine generally. In contrast, a considerable portion of this inorganic selenium compound is metabolized by individuals, which eliminate TMSe basically. An elevated metabolism may also be provided by individuals, which eliminate high levels of selenium-containing carbohydrates basically. The difference in metabolism may imply a different disposition for pharmacological or toxic effects by exposure to inorganic selenium compounds.


Assuntos
Suplementos Nutricionais , Eliminação Renal , Ácido Selênico/farmacocinética , Compostos de Selênio/metabolismo , Administração Oral , Adulto , Biotransformação , Cromatografia Líquida , Suplementos Nutricionais/efeitos adversos , Feminino , Galactose/análogos & derivados , Galactose/metabolismo , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Ácido Selênico/administração & dosagem , Ácido Selênico/efeitos adversos , Ácido Selênico/sangue , Ácido Selênico/urina , Compostos de Selênio/urina , Espectrofotometria Atômica , Adulto Jovem
13.
Am J Clin Nutr ; 102(5): 1126-33, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26468123

RESUMO

BACKGROUND: Selenomethionine, which is the principal dietary form of selenium, is metabolized by the liver to selenide, which is the form of the element required for the synthesis of selenoproteins. The liver synthesizes selenium-rich selenoprotein P (SEPP1) and secretes it into the plasma to supply extrahepatic tissues with selenium. OBJECTIVES: We conducted a randomized controlled trial to determine whether cirrhosis is associated with functional selenium deficiency (the lack of selenium for the process of selenoprotein synthesis even though selenium intake is not limited) and, if it is, whether the deficiency is associated with impairment of selenomethionine metabolism. DESIGN: Patients with Child-Pugh (C-P) classes A, B, and C (mild, moderate, and severe, respectively) cirrhosis were supplemented with a placebo or supranutritional amounts of selenium as selenate (200 or 400 µg/d) or as selenomethionine (200 µg/d) for 4 wk. Plasma SEPP1 concentration and glutathione peroxidase (GPX) activity, the latter due largely to the selenoprotein GPX3 secreted by the kidneys, were measured before and after supplementation. RESULTS: GPX activity was increased more by both doses of selenate than by the placebo in C-P class B patients. The activity was not increased more by selenomethionine supplementation than by the placebo in C-P class B patients. Plasma selenium was increased more by 400 µg Se as selenate than by the placebo in C-P class C patients. Within the groups who responded to selenate, there was a considerable variation in responses. CONCLUSION: These results indicate that severe cirrhosis causes mild functional selenium deficiency in some patients that is associated with impaired metabolism of selenomethionine. This trial was registered at clinicaltrials.gov as NCT00271245.


Assuntos
Deficiências Nutricionais/dietoterapia , Suplementos Nutricionais , Cirrose Hepática/fisiopatologia , Estado Nutricional , Ácido Selênico/uso terapêutico , Selênio/deficiência , Adulto , Biomarcadores/sangue , Deficiências Nutricionais/sangue , Deficiências Nutricionais/epidemiologia , Deficiências Nutricionais/etiologia , Suplementos Nutricionais/efeitos adversos , Feminino , Glutationa Peroxidase/sangue , Humanos , Incidência , Masculino , Metionina/sangue , Pessoa de Meia-Idade , Projetos Piloto , Ácido Selênico/administração & dosagem , Ácido Selênico/efeitos adversos , Selênio/administração & dosagem , Selênio/sangue , Selênio/uso terapêutico , Selenometionina/efeitos adversos , Selenometionina/uso terapêutico , Selenoproteína P/sangue , Índice de Gravidade de Doença , Tennessee/epidemiologia
14.
J Trace Elem Med Biol ; 31: 142-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24908353

RESUMO

Despite different geological features the Nordic countries are generally selenium-poor areas. In each country various factors such as food importation and life-style determine the selenium (Se) intake. Due to an extremely low Se intake in the 1970s in Finland, 0.025 mg/day, an official decision was made in 1984 to supplement multinutrient fertilizers with Se in the chemical form of sodium selenate. Almost all fertilizers used in Finland since 1985 have contained Se. Currently all crop fertilizers contain 15 mg Se/kg. Finland is still the only country to take this country-wide measure. In a national monitoring programme, sampling of cereals, basic foodstuffs, feeds, fertilizers, soils, and human tissues has been carried out annually since 1985 by four governmental research organizations. Sampling of foods has been done four times per year and human blood has been obtained annually from the same (n=60) adults. The accuracy of analyses has been verified by annual interlaboratory quality control. During this programme the selenium concentration of spring cereals has increased on average 15-fold compared with the level before the Se fertilization. The mean increase in the Se concentration in beef, pork and milk was 6-, 2- and 3-fold. In terms of Se, organically grown foods of plant origin are generally comparable to products produced before the Se supplementation of fertilizers. Milk from organically fed cows is 50% lower in Se than the usual milk. The average dietary human intake increased from 0.04 mg Se/day/10 MJ in 1985 to a present plateau of 0.08 mg Se/day/10 MJ, which is well above the current nutrition recommendations. Foods of animal origin contribute over 70% of the total daily Se intake. The mean human plasma Se concentration increased from 0.89 µmol/L to a general level of 1.40 µmol/L that can be considered to be an optimal status. The absence of Se deficiency diseases and a reference population have made conclusions on the impact on human health difficult. However, the rates of cardiovascular diseases and cancers have remained similar during the pre- and post-supplementation indicating medical and life-style factors to be much stronger determinants than Se. The nationwide supplementation of fertilizers with sodium selenate is shown to be effective and safe in increasing the Se intake of the whole population. Also, the health of animals has improved.


Assuntos
Bem-Estar do Animal , Produtos Agrícolas/química , Deficiências Nutricionais/prevenção & controle , Fertilizantes , Política Nutricional , Estado Nutricional , Selênio/administração & dosagem , Animais , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/metabolismo , Deficiências Nutricionais/veterinária , Finlândia , Humanos , Ácido Selênico/administração & dosagem , Ácido Selênico/metabolismo , Ácido Selênico/uso terapêutico , Selênio/deficiência , Selênio/metabolismo , Selênio/uso terapêutico
15.
Exp Parasitol ; 144: 39-43, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24950380

RESUMO

The aim of this study was to evaluate the effects of selenium and copper on oxidative stress and its performance in lambs experimentally infected with Haemonchus contortus. Twenty-eight five-months old lambs were experimentally infected by the oral route with 5000 third-stage infective larvae and allocated into four groups, i.e., untreated animals, animals treated intramuscularly with sodium selenite (0.2 mg kg(-1)), animals treated subcutaneously with copper (3.5 mg kg(-1)), and animals treated with sodium selenite (IM; 0.2 mg kg(-1)) and copper (SC; 3.5 mg kg(-1)). These animals received oat hay (Avena sativa) and commercial concentrate, totaling 15% of crude protein, 30% being derived from oat hay and 70% of the concentrate. Lipid peroxidation, antioxidant enzymes, eggs per gram of feces (EPG) and body weight were assessed on the day of infection and after 20, 40, 60 and 80 days post-infection. The number of H. contortus adults was assessed at the end of the experiment. The selenium associated or not with copper reduced the effects of oxidative stress caused by infection. The groups supplemented with copper had increased body weight, and the combination of these two minerals reduced the EPG and number of H. contortus adults in lambs. The use of selenium associated with copper may help the control of infection by H. contortus.


Assuntos
Antioxidantes/administração & dosagem , Cobre/administração & dosagem , Hemoncose/veterinária , Ácido Selênico/administração & dosagem , Doenças dos Ovinos/prevenção & controle , Animais , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Catalase/sangue , Cobre/farmacologia , Cobre/uso terapêutico , Fezes/parasitologia , Glutationa Peroxidase/sangue , Hemoncose/tratamento farmacológico , Hemoncose/imunologia , Hemoncose/prevenção & controle , Hematócrito/veterinária , Imunocompetência/efeitos dos fármacos , Injeções Intramusculares/veterinária , Injeções Subcutâneas/veterinária , Peroxidação de Lipídeos , Masculino , Estresse Oxidativo/efeitos dos fármacos , Contagem de Ovos de Parasitas/veterinária , Ácido Selênico/farmacologia , Ácido Selênico/uso terapêutico , Ovinos , Doenças dos Ovinos/tratamento farmacológico , Doenças dos Ovinos/imunologia , Substâncias Reativas com Ácido Tiobarbitúrico/análise , Aumento de Peso
16.
ScientificWorldJournal ; 2014: 401265, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24688385

RESUMO

The aim of this work was to study the effect of Se(+VI) on viability, cell morphology, and selenomethionine accumulation of the green alga Chlorella sorokiniana grown in batch cultures. Culture exposed to sublethal Se concentrations of 40 mg · L(-1) (212 µM) decreased growth rates for about 25% compared to control. A selenate EC50 value of 45 mg · L(-1) (238.2 µM) was determined. Results showed that chlorophyll and carotenoids contents were not affected by Se exposure, while oxygen evolution decreased by half. Ultrastructural studies revealed granular stroma, fingerprint-like appearance of thylakoids which did not compromise cell activity. Unlike control cultures, SDS PAGE electrophoresis of crude extracts from selenate-exposed cell cultures revealed appearance of a protein band identified as 53 kDa Rubisco large subunit of Chlorella sorokiniana, suggesting that selenate affects expression of the corresponding chloroplast gene as this subunit is encoded in the chloroplast DNA. Results revealed that the microalga was able to accumulate up to 140 mg · kg(-1) of SeMet in 120 h of cultivation. This paper shows that Chlorella sorokiniana biomass can be enriched in the high value aminoacid SeMet in batch cultures, while keeping photochemical viability and carbon dioxide fixation activity intact, if exposed to suitable sublethal concentrations of Se.


Assuntos
Técnicas de Cultura Celular por Lotes/métodos , Reatores Biológicos/microbiologia , Chlorella/citologia , Chlorella/fisiologia , Ácido Selênico/administração & dosagem , Selenometionina/isolamento & purificação , Selenometionina/metabolismo , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/fisiologia , Tamanho Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Chlorella/efeitos dos fármacos , Relação Dose-Resposta a Droga
17.
Nutrients ; 6(3): 1251-61, 2014 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-24667132

RESUMO

Selenium food fortification could be a cost-effective strategy to counteract the inadequacy of selenium intake among the Italian population. In this study, the effect of foliar fertilization with sodium selenate of an Italian rice cultivar and the increase of serum selenium and of erythrocyte glutathione peroxidase (GPx) activity after intake of fortified rice, have been evaluated. The effect of foliar fertilization with sodium selenate (50 g Se/ha) vs. water was studied. Moreover, in a randomized, double-blind study, 10 healthy women supplemented their usual diet with a daily dose of 80 g of Se-enriched-rice and 10 matched-women with 80 g of regular rice. Before, after 5 and 20 days of supplementation, serum Se and GPx-activity were evaluated. The mean selenium content in Se-enriched-rice was 1.64 ± 0.28 µg/g, while in regular rice it was 0.36 ± 0.15 µg/g (p < 0.001). A significant increase of serum Se and GPx-activity was observed only in the intervention group and only after 20 days. The results show that selenium fortification of rice can be achieved with foliar fertilization with sodium selenate and that the 20 days intake of this Se-enriched-rice increases the serum selenium levels and GPx-activity.


Assuntos
Suplementos Nutricionais , Eritrócitos/efeitos dos fármacos , Alimentos Fortificados , Glutationa Peroxidase/sangue , Oryza/química , Ácido Selênico/sangue , Adulto , Índice de Massa Corporal , Dieta , Método Duplo-Cego , Eritrócitos/metabolismo , Feminino , Humanos , Itália , Modelos Lineares , Ácido Selênico/administração & dosagem , Selênio/sangue , Adulto Jovem
18.
In Vivo ; 27(6): 869-71, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24292594

RESUMO

BACKGROUND: This clinical investigation was performed in order to evaluate the benefit of complementary medicine in patients with breast cancer undergoing adjuvant hormone therapy (HT). PATIENTS AND METHODS: The patients (n=680) were treated according to international guidelines. All patients suffered from arthralgia and mucosal dryness induced by the adjuvant HT. In order to reduce side-effects, the patients were complementarily treated with a combination of sodium selenite, proteolytic plant enzymes (bromelaine and papain) and Lens culinaris lectin. On case report formulas, self assessment of defined side-effects of HT (namely arthralgia and mucosal dryness) were documented before and four weeks after complementary treatment. Validation was carried out by scoring from 1 (no side-effects/optimal tolerability) to 6 (extreme side-effects/extremely poor tolerability), however, only patients suffering from severe side-effects (symptom scores >3) were enrolled in this investigation. RESULTS: A total of 64% (316 out of 494) of patients suffering from severe arthralgia and 62% of patients (194 out of 310) with severe mucosal dryness significantly benefited from complementary medicine. The severity of side-effects of HT was reduced by complementary treatment. Mean scores of symptoms declined from 4.92 before treatment to 3.16 after four weeks of treatment for arthralgia and from 4.83 before treatment to 3.21 after four weeks of treatment for mucosal dryness, and these were the primary aims of this investigation. The reduction of side-effects of HT was statistically significant (p<0.001) after four weeks. CONCLUSION: This investigation further demonstrates benefits of indication-based complementary treatment with the combination of sodium selenite, proteolytic enzymes and L. culinaris lectin in patients with breast cancer.


Assuntos
Antineoplásicos Hormonais/efeitos adversos , Artralgia/tratamento farmacológico , Neoplasias da Mama/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Ácido Selênico/administração & dosagem , Xerostomia/tratamento farmacológico , Antineoplásicos Hormonais/uso terapêutico , Artralgia/induzido quimicamente , Bromelaínas/administração & dosagem , Quimioterapia Adjuvante/efeitos adversos , Terapias Complementares , Feminino , Humanos , Pessoa de Meia-Idade , Papaína/administração & dosagem , Lectinas de Plantas/administração & dosagem , Xerostomia/induzido quimicamente
19.
Res Vet Sci ; 95(3): 1163-8, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24210249

RESUMO

Sheep can be acutely poisoned by selenium (Se) accumulating forages which often contain selenate or Se-methylselenocysteine as their predominant forms. Excess Se can be eliminated via respiration. Sheep were given a single oral dose of 0, 1, 2, 3, 4, or 6 mg Se/kg BW as sodium selenate and Se-methylselenocysteine or 6 mg Se/kg BW as sodium selenite or selenomethionine. Expired air samples were collected and analyzed for Se. The Se concentration of the expired air reflected a dose-dependent increase at individual time points for both Se-methylselenocysteine and sodium selenate, however, Se content was greater and eliminated more rapidly from sheep receiving Se-methylselenocysteine. The mean Se concentration in respired air from sheep administered 6 mg Se/kg BW of different selenocompounds was greatest in sheep dosed Se-methylselenocysteine > selenomethionine > sodium selenate > sodium selenite. The Se concentration in respired air of acutely poisoned sheep is significantly different for different chemical forms of Se.


Assuntos
Ácido Selênico/farmacocinética , Selenocisteína/análogos & derivados , Administração Oral , Animais , Testes Respiratórios , Relação Dose-Resposta a Droga , Expiração , Ácido Selênico/administração & dosagem , Ácido Selênico/análise , Selenocisteína/administração & dosagem , Selenocisteína/análise , Selenocisteína/farmacocinética , Ovinos
20.
Biomed Res Int ; 2013: 231378, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24106697

RESUMO

Metformin is widely regarded as the standard first-line antidiabetic agent, in terms of efficacy and safety profiles. However, in most patients with type II diabetes mellitus (T2DM), it was found that metformin alone is not enough to adequately control hyperglycemia. Thus, we designed this study with the aim to investigate the effect of sodium selenate, a protein tyrosine phosphatase (PTP) inhibitor, individually and as an adjunct to metformin, on a rat model that simulates the metabolic characteristics of human T2DM. T2DM model was achieved by feeding the rats with high-fat, high-fructose diet (HFFD) for 8 weeks followed by a low dose of streptozotocin (STZ) (35 mg/kg/day, i.p.). Changes in serum glucose, insulin, adiponectin, homeostasis model assessment of insulin resistance (HOMA-IR) index, and the lipid profile were assessed. In addition, the level of reduced glutathione (GSH) and the activity of PTP were determined in the liver. Results showed that the addition of sodium selenate to metformin was able to restore hepatic GSH back to normal levels. Also, this combination therapy corrected the altered serum total cholesterol (TC), triglycerides (TG), and adiponectin levels. In conclusion, additive therapeutic effect was recorded when sodium selenate was used as an adjunct to metformin.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hiperglicemia/tratamento farmacológico , Ácido Selênico/administração & dosagem , Adiponectina/sangue , Animais , Glicemia/efeitos dos fármacos , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/patologia , Sinergismo Farmacológico , Humanos , Hiperglicemia/complicações , Hiperglicemia/patologia , Insulina/sangue , Metformina/administração & dosagem , Ratos
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