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1.
J Environ Pathol Toxicol Oncol ; 38(3): 253-270, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31679312

RESUMO

Di(2-ethylhexyl)phthalate (DEHP) is the most widely used phthalate. DEHP is highly used in PVC floorings and PVC windows and carpeting. The objective of this study was to determine sex hormone levels, oxidative stress parameters, selenium levels, DNA damage, and phthalate levels in plastics workers (n = 24, age = 20-58 years) working in the production of rubber mechanical goods and exposed to DEHP in workplace. The control group (n = 29, age = 25-54, all male) was selected from age-matched healthy adults. Antioxidant parameters and DNA damage were determined by spectrophotometry. Selenium levels were determined by atomic absorption spectroscopy. Plasma hormone levels were measured by chemiluminescence microparticle immunoassay. Plasma phthalate levels were determined by high-pressure liquid chromatography. Plastic workers had lower serum testosterone and free T4 levels and higher follicle-stimulating hormone levels vs. controls. Liver enzyme activities were markedly higher in workers vs. controls. There were also increases in plasma glutathione peroxidase levels and marked decreases in plasma selenium and erythrocyte total glutathione levels in plastics workers (P < 0.05 vs. control). Plasma 8-hydroxy-2'-deoxyguanosine levels were 14-fold higher in plastics workers than in controls. Plasma DEHP and mono(2-ethylhexyl)phthalate were also markedly higher in workers vs. controls. The results of this study show that occupational exposure to DEHP may lead to disturbances in sex hormones, increased liver problems, higher oxidative stress and DNA damage levels, and lower trace element concentrations in workers. More comprehensive and mechanistic studies with higher numbers of subjects are needed to show the unwanted effects of occupational exposure to DEHP.


Assuntos
Dano ao DNA , Dietilexilftalato/análogos & derivados , Dietilexilftalato/toxicidade , Poluentes Ambientais/toxicidade , Exposição Ocupacional/efeitos adversos , Estresse Oxidativo/efeitos dos fármacos , Selênio/metabolismo , Adulto , Hormônios Esteroides Gonadais/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Turquia
2.
J Microbiol ; 57(9): 738-747, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31376106

RESUMO

The simultaneous removal of phenol and selenite from synthetic wastewater was investigated by adopting two different co-culturing techniques using the fungus Phanerochaete chrysosporium and the bacterium Delftia lacustris. Separately grown biomass of the fungus and the bacterium (suspended co-culture) was incubated with different concentrations of phenol (0-1,200 mg/L) and selenite (10 mg/L). The selenite ions were biologically reduced to extracellular Se(0) nanoparticles (3.58 nm diameter) with the simultaneous degradation of up to 800 mg/L of phenol. Upon growing the fungus and the bacterium together using an attached growth co-culture, the bacterium grew as a biofilm onto the fungus. The extracellularly produced Se(0) in the attached growth co-culture had a minimum diameter of 58.5 nm. This co-culture was able to degrade completely 50 mg/L phenol, but was completely inhibited at a phenol concentration of 200 mg/L.


Assuntos
Delftia/metabolismo , Phanerochaete/metabolismo , Fenol/metabolismo , Ácido Selenioso/metabolismo , Selênio/metabolismo , Biodegradação Ambiental , Biotransformação , Técnicas de Cocultura , Delftia/crescimento & desenvolvimento , Oxirredução , Phanerochaete/crescimento & desenvolvimento , Águas Residuárias/microbiologia , Poluentes da Água/metabolismo
3.
Environ Res ; 177: 108642, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31430668

RESUMO

Selenium (Se) is an essential micronutrient but toxic when taken in excessive amounts. Therefore, understanding the metabolic processes related to selenium uptake and bacteria-plant interactions coupled with selenium metabolism are of high importance. We cultivated Brassica oleracea with the previously isolated heterotrophic aerobic Se(IV)-reducing Pseudomonas sp. T5-6-I strain to better understand the phenomena of bacteria-mediated Se(IV) reduction on selenium availability to the plants. B. oleracea grown on Murashige and Skoog medium (MS-salt agar) with and without of Pseudomonas sp. were amended with Se(IV)/75Se(IV), and selenium transfer into plants was studied using autoradiography and gamma spectroscopy. XANES was in addition used to study the speciation of selenium in the B. oleracea plants. In addition, the effects of Se(IV) on the protein expression in B. oleracea was studied using HPLC-SEC. TEM and confocal microscopy were used to follow the bacterial/Se-aggregate accumulation in plants and the effects of bacterial inoculation on root-hair growth. In the tests using 75Se(IV) on average 130% more selenium was translocated to the B. oleracea plants grown with Pseudomonas sp. compared to the plants grown with selenium, but without Pseudomonas sp.. In addition, these bacteria notably increased root hair density. Changes in the protein expression of B. oleracea were observed on the ∼30-58 kDa regions in the Se(IV) treated samples, probably connected e.g. to the oxidative stress induced by Se(IV) or expression of proteins connected to the Se(IV) metabolism. Based on the XANES measurements, selenium appears to accumulate in B. oleracea mainly in organic C-Se-H and C-Se-C bonds with and without bacteria inoculation. We conclude that the Pseudomonas sp. T5-6-I strain seems to contribute positively to the selenium accumulation in plants, establishing the high potential of Se0-producing bacteria in the use of phytoremediation and biofortification of selenium.


Assuntos
Brassica/metabolismo , Brassica/microbiologia , Pseudomonas/metabolismo , Selênio/metabolismo , Biodegradação Ambiental
4.
Bioengineered ; 10(1): 335-344, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31322471

RESUMO

Selenium-enriched yeast can transform toxic inorganic selenium into absorbable organic selenium, which is of great significance for human health and pharmaceutical industry. A yeast Rhodotorula glutinis X-20 we obtained before has good selenium-enriched ability, but its selenium content is still low for industrial application. In this study, strategies of process optimization and transport regulation of selenium were thus employed to further improve the cell growth and selenium enrichment. Through engineering phosphate transporters from Saccharomyces cerevisiae into R. glutinis X-20, the selenium content was increased by 21.1%. Through using mixed carbon culture (20 g L-1, glycerol: glucose 3:7), both biomass and selenium content were finally increased to 5.3 g L-1 and 5349.6 µg g-1 (cell dry weight, DWC), which were 1.14 folds and 6.77 folds compared to their original values, respectively. Our results indicate that high selenium-enrichment ability and biomass production can be achieved through combining process optimization and regulation of selenium transport.


Assuntos
Engenharia Metabólica/métodos , Fosfatos/metabolismo , Rhodotorula/genética , Saccharomyces cerevisiae/genética , Selênio/metabolismo , Transgenes , Transporte Biológico , Biomassa , Meios de Cultura/química , Meios de Cultura/farmacologia , Fermentação , Expressão Gênica , Glucose/química , Glucose/metabolismo , Glicerol/química , Glicerol/metabolismo , Proteínas de Transporte de Fosfato/genética , Proteínas de Transporte de Fosfato/metabolismo , Plasmídeos/química , Plasmídeos/metabolismo , Simportadores de Próton-Fosfato/genética , Simportadores de Próton-Fosfato/metabolismo , Rhodotorula/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas Cotransportadoras de Sódio-Fosfato Tipo III/genética , Proteínas Cotransportadoras de Sódio-Fosfato Tipo III/metabolismo
5.
Sci Total Environ ; 691: 827-834, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31326806

RESUMO

Selenium (Se) is an essential element in animals and humans, and its deficiency may cause conditions such as cardiac disease. The production of Se-enriched rice is one of the most important ways to supply Se in the human body, and thus, understanding of the mechanisms of Se-enriched rice is of great significance. A pot experiment was conducted to study the effects of Se addition on the growth, antioxidation, Se uptake and distribution, and Se speciation in three different stages of panicle initiation stage (i.e., pistil and stamen formation stage, pollen mother cell formation stage, pollen mother cell meiosis stage) and the maturity stage. The results showed that soil Se application significantly increased Se uptake in rice. Low rates of Se (<5 mg kg-1) application enhanced the plant growth and rice yield. Se speciation assays showed that SeCys and SeMet were the two main forms found in rice, of which SeMet accounted for 65.5%-100% in the ears and leaves, while SeCys accounted for 61.4%-75.6% in brown rice. SeMet was also the main Se-species found in different subcellular parts at the panicle initiation stage. However, inorganic Se was present in brown rice, mainly as Se(VI), when the soil Se addition exceeded 5 mg kg-1. Lower rates of Se (<5 mg kg-1) promoted the antioxidant capacity, while high levels of Se (≥5 mg kg-1) reduced the antioxidant capacity of rice. The results indicate that Se effects are dose dependent, and the suitable amount of soil Se application for Se-enriched rice production would be <5 mg kg-1.


Assuntos
Antioxidantes/metabolismo , Oryza/fisiologia , Selênio/metabolismo , Poluentes do Solo/metabolismo
6.
J Agric Food Chem ; 67(29): 8096-8106, 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31260296

RESUMO

Field experiments were conducted on wheat to study the effects of foliar-applied iodine(I) alone, Zn (zinc) alone, and a micronutrient cocktail solution containing I, Zn, Se (selenium), and Fe (iron) on grain yield and grain concentrations of micronutrients. Plants were grown over 2 years in China, India, Mexico, Pakistan, South Africa, and Turkey. Grain-Zn was increased from 28.6 mg kg-1 to 46.0 mg-1 kg with Zn-spray and 47.1 mg-1 kg with micronutrient cocktail spray. Foliar-applied I and micronutrient cocktail increased grain I from 24 µg kg-1 to 361 µg kg-1 and 249 µg kg-1, respectively. Micronutrient cocktail also increased grain-Se from 90 µg kg-1 to 338 µg kg-1 in all countries. Average increase in grain-Fe by micronutrient cocktail solution was about 12%. The results obtained demonstrated that foliar application of a cocktail micronutrient solution represents an effective strategy to biofortify wheat simultaneously with Zn, I, Se and partly with Fe without yield trade-off in wheat.


Assuntos
Biofortificação/métodos , Produção Agrícola/métodos , Iodo/metabolismo , Ferro/metabolismo , Selênio/metabolismo , Triticum/metabolismo , Zinco/metabolismo , China , Fertilizantes/análise , Índia , Iodo/análise , Ferro/análise , México , Micronutrientes/análise , Micronutrientes/metabolismo , Paquistão , Folhas de Planta/química , Folhas de Planta/metabolismo , Sementes/química , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Selênio/análise , África do Sul , Triticum/química , Triticum/crescimento & desenvolvimento , Turquia , Zinco/análise
7.
J Sci Food Agric ; 99(14): 6364-6371, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31273805

RESUMO

BACKGROUND: Biofortification with selenium (Se) elevates its concentration in feed and fodder plants and helps to prevent health problems in animals and humans. The aim of this study was to describe Se-induced modifications in the accumulation of elements important for the proper functioning of wheat, one of the most popular cereals. The presence of Se correlated with carbohydrate synthesis and electron paramagnetic resonance (EPR). This explained the mechanisms of Se's antioxidant activity. RESULTS: Selenium accumulation in vegetative and generative leaves, and in the grains of three wheat genotypes (cv. Parabola, cv. Raweta and cv. Manu), differing in their stress tolerance and grown hydroponically in the presence of 10 or 20 µM Na2 SeO4, , was proportional to its content in the medium. Stronger Se accumulation was typical of a stress-sensitive genotype. Selenium generally promoted the uptake of macronutrients and micronutrients but their distribution depended on tissue and genotype. Changes in the Se-induced EPR signals of paramagnetic metals and organic radicals corresponded with stress tolerance of the tested genotypes. CONCLUSIONS: Se application increased the accumulation of nutrients and carbohydrates that are vital for proper plant growth and development. Accelerated uptake of molybdenum (Mo), an element improving dietary properties of grains, may be an additional advantage of Se fertilization. The mechanisms of Se-induced changes in removing Mn and iron (Fe) ions from macromolecules may be one of the factors that differentiate plant tolerance to oxidative stress. © 2019 Society of Chemical Industry.


Assuntos
Selênio/metabolismo , Açúcares/metabolismo , Triticum/crescimento & desenvolvimento , Triticum/metabolismo , Espectroscopia de Ressonância de Spin Eletrônica , Genótipo , Ferro/análise , Ferro/metabolismo , Micronutrientes/análise , Micronutrientes/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Selênio/análise , Açúcares/análise , Triticum/química , Triticum/genética
8.
Environ Sci Pollut Res Int ; 26(23): 23453-23459, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31201704

RESUMO

Cadmium (Cd) as a widespread toxic heavy metal accumulates in animal food including chicken meat through food chain enrichment and finally threatens human health. Selenium (Se) is an essential mineral and possesses antagonistic effects on Cd-induced multiple organs' toxicity in chickens. The objective of the present study was to reveal the antagonistic mechanisms of Se to Cd from the aspects of oxidative stress, inflammation, and meat quality in chicken breast muscles. Firstly, the results showed that Cd significantly elevated the levels of malondialdehyde (MDA), hydrogen peroxide (H2O2), and protein carbonyl, and declined the levels of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), and catalase (CAT) to trigger oxidative stress in chicken breast muscles. However, Se treatment significantly alleviated Cd-induced oxidative stress by increasing the levels of GSH-Px, SOD, and CAT, and decreasing the levels of MDA, H2O2, and protein carbonyl. Secondly, Se obviously inhibited the expressions of Cd-activated inflammation-related genes including tumor necrosis factor (TNF-α), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), inducible nitric oxide synthase (iNOS), prostaglandin-endoperoxide synthase 2 (COX-2), and prostaglandin E synthase (PTGEs) in chicken breast muscles. Thirdly, meat quality-related parameters including pH45min, ultimate pH (pHu), and drip loss were also detected, and the results showed that Se markedly recovered Cd-induced dropt of pH45min and increase of drip loss in chicken breast muscles. In brief, these findings demonstrated that Se significantly alleviated Cd-induced oxidative stress and inflammation, and declined meat quality of chicken breast muscles.


Assuntos
Antioxidantes/metabolismo , Cádmio/toxicidade , Galinhas/fisiologia , Poluentes Ambientais/toxicidade , Carne/análise , Selênio/metabolismo , Animais , Cádmio/metabolismo , Catalase/metabolismo , Galinhas/metabolismo , Glutationa Peroxidase/metabolismo , Peróxido de Hidrogênio/metabolismo , Inflamação , Malondialdeído/metabolismo , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Superóxido Dismutase/metabolismo
9.
J Sci Food Agric ; 99(12): 5601-5605, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31149731

RESUMO

BACKGROUND: Microgreens (i.e. tender immature greens) are a popular alternative to sprouts (i.e. germinating seeds) because of their higher content of vitamins, carotenoids and phenols, as well as their lower content of nitrates. Their nutritional value can be improved by biofortification, which increases micronutrient levels during plant growth. Because selenium (Se) plays a significant role in antioxidant defense, biofortification with Se is a good way of improving the nutritional quality of sprouts and microgreens. The present study investigated the production of Se-fortified microgreens from Se-enriched seeds of sweet basil (Ocimum basilicum L.). These microgreens could be used as new beneficial dietary supplements. RESULTS: Basil plants were grown in a nutrient solution, containing 0 (control), 4 or 8 mg Se L-1 as sodium selenate, to full maturity. Seeds accumulated a high amount of Se and were then used to produce microgreens. The germination index was higher in the seeds from Se-treated plants and the microgreens were enriched in Se. The antioxidant capacity of Se-fortified microgreens was higher compared to the control. CONCLUSION: The production of microgreens from Se-enriched seeds could comprise a good system for obtaining microgreens with a high nutritional value. Basil plants treated with Se could be used to produce both Se-fortified leaves and microgreens. © 2019 Society of Chemical Industry.


Assuntos
Ocimum basilicum/química , Selênio/análise , Antioxidantes/análise , Antioxidantes/metabolismo , Biofortificação , Fertilizantes/análise , Alimentos Fortificados/análise , Germinação , Valor Nutritivo , Ocimum basilicum/crescimento & desenvolvimento , Ocimum basilicum/metabolismo , Fenóis/análise , Fenóis/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Sementes/química , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Selênio/metabolismo
10.
Environ Pollut ; 252(Pt B): 1180-1192, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31252116

RESUMO

The increasing consumption of anticancer drugs through single and/or combinatory chemotherapy worldwide raised concern regarding their toxicity burden in coastal zones. The toxicity of a mixture of three compounds involving the drugs cisplatin (CisPt), cyclophosphamide (CP) and tamoxifen (TAM) was determined on the marine polychaete Nereis diversicolor exposed to an increasing range of their concentrations, respectively: Mix A: 0.1 + 10 + 0.1 ng L-1; Mix B: 10 + 100 + 10 ng L-1; Mix C: 100 + 500 + 25 ng L-1; Mix D: 100 + 1000 + 100 ng L-1. Different endpoints were assessed, including disturbance in the burrowing behaviour, neurotoxicity (acetylcholinesterase - AChE activity), antioxidant enzymes (superoxide dismutase - SOD; catalase - CAT; selenium-dependent glutathione peroxidase - Se-GPx and total glutathione peroxidases T-GPx activities), biotransformation metabolism (glutathione-S-transferases - GST), lipid peroxidation (LPO) and genotoxicity (DNA damage). Biological effects of the mixtures of anticancer compounds on N. diversicolor were compared with previous studies about effects on the same biological model under single-drug exposure conducted with the same molecules. Regarding SOD activity, TAM showed an antagonist effect over CisPt and CP in mixtures C and D. In Mix D, there was a synergistic effect of TAM and CisPt that inhibited CAT activity and an additive interaction of CisPt and CP on the Phase II biotransformation enzyme. Drugs in Mix A also suppressed polychaetes' GST activity, although different from the respective single-drug responses, besides able to induce T-GPx activity, that was not sufficient to avoid oxidative damage and mid-grade DNA damage. Due to the absence of burrowing impairment in Mix A, mechanisms involved in neurotoxicity were other than the one driven by AChE alterations. At the intermediary concentrations (Mix B and C), only LPO occurred. Data from drugs individually may not predict the risks provided by mixtures.


Assuntos
Antineoplásicos/toxicidade , Poliquetos/fisiologia , Poluentes Químicos da Água/toxicidade , Acetilcolinesterase/metabolismo , Animais , Antineoplásicos/metabolismo , Antioxidantes/metabolismo , Biotransformação , Catalase/metabolismo , Ciclofosfamida/metabolismo , Dano ao DNA , Glutationa Peroxidase/metabolismo , Glutationa Transferase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Poliquetos/metabolismo , Selênio/metabolismo , Superóxido Dismutase/metabolismo
11.
Environ Sci Pollut Res Int ; 26(24): 24430-24444, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31230234

RESUMO

Regarding the rapid progress in the production and consumption of nanobased products, this research considered the behavior of Melissa officinalis toward zinc oxide nanoparticles (nZnO), nanoelemental selenium (nSe), and bulk counterparts. Seedlings were irrigated with nutrient solution containing different doses of nZnO (0, 100, and 300 mg l-1) and/or nSe (0, 10, and 50 mg l-1). The supplements made changes in growth and morphological indexes in both shoot and roots. The mixed treatments of nSe10 and nZnO led to a drastic increase in biomass, activation of lateral buds, and stimulations in the development of lateral roots. However, the nSe50 reduced plants' growth (45.5%) and caused severe toxicity which was basically lower than the bulk. Furthermore, the nSe and nZnO improved K, Fe, and Zn concentrations in leaves and roots, except for seedlings exposed to nSe50 or BSe50. Moreover, the nSe and nZnO supplementations in a dose-dependent manner caused changes in leaf non-protein thiols (mean = 77%), leaf ascorbate content (mean = 65%), and soluble phenols in roots (mean = 28%) and leaves (mean = 61%). In addition, exposure to nZnO and/or nSe drastically induced the expression of rosmarinic acid synthase (RAS) and Hydroxy phenyl pyruvate reductase (HPPR) genes. Besides, the nSe, nZnO, or bulk counterparts influenced the activities of nitrate reductase in leaves and peroxidase in roots, depending on dose factor and compound form. The comparative physiological and molecular evidence on phytotoxicity and potential advantages of nSe, nZnO, and their bulk counterparts were served as a theoretical basis to be exploited in food, agricultural, and pharmaceutical industries.


Assuntos
Melissa/genética , Nanopartículas/toxicidade , Selênio/toxicidade , Óxido de Zinco/toxicidade , Biodegradação Ambiental , Nanopartículas/metabolismo , Selênio/metabolismo , Óxido de Zinco/metabolismo
12.
Environ Sci Pollut Res Int ; 26(24): 24532-24541, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31236863

RESUMO

Se can regulate Cd accumulation and translocation in plants; however, such effects can be controversial because of the differences in plant species and Se species. In this study, pak choi was cultured under hydroponic conditions, and the effects of selenite and selenate on Cd accumulation were investigated in the edible parts of this vegetable. The results showed gradual improvements in the effects of the two Se species on the Cd content in pak choi shoots at the four assessed growing stages. Selenite did not lead to significant changes in Cd accumulation in the shoots until day 40, when it significantly reduced the accumulation by 34%. Selenate was always found to increase the Cd content in the shoots, and the differences on days 19 and 40 were 16% and 45%, respectively, compared with those of the Cd (only) treatment. Accordingly, selenate invariably enhanced Cd translocation from the roots to the shoots, whereas selenite insignificantly reduced the translocation only on day 40. Generally, selenomethionine (SeMet) accounted for much larger proportions in selenite-treated plants, while SeO42- was the dominant Se species in selenate-treated plants. However, under both Se treatments, the SeMet proportion increased substantially from day 19 to day 40 when that of SeO42- exhibited a drastic decrease; therefore, the relative proportion of seleno-amino acids to SeO42- may be the key factor for the regulation of Cd accumulation in pak choi via treatment with selenite and selenate at the different growing stages.


Assuntos
Brassica/metabolismo , Metais/metabolismo , Ácido Selênico/metabolismo , Ácido Selenioso/metabolismo , Poluentes do Solo/metabolismo , Brassica/efeitos dos fármacos , Cádmio/metabolismo , Hidroponia , Raízes de Plantas , Selênio/metabolismo , Compostos de Selênio , Selenito de Sódio
13.
Environ Health Prev Med ; 24(1): 40, 2019 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-31174461

RESUMO

BACKGROUND: Placenta previa and placenta accreta associate with high morbidity and mortality for both mothers and fetus. Metal exposure may have relationships with placenta previa and placenta accreta. This study analyzed the associations between maternal metal (cadmium [Cd], lead [Pb], mercury [Hg], selenium [Se], and manganese [Mn]) concentrations and placenta previa and placenta accreta. METHODS: We recruited 17,414 women with singleton pregnancies. Data from a self-administered questionnaire regarding the first trimester and medical records after delivery were analyzed. Maternal blood samples were collected to measure metal concentrations. The subjects were classified into four quartiles (Q1, Q2, Q3, and Q4) according to metal concentrations. RESULTS: The odds ratio for placenta previa was significantly higher among subjects with Q4 Cd than those with Q1 Cd. The odds ratio for placenta previa was significantly higher for subjects with Q2 Pb than those with Q1 Pb. CONCLUSION: Participants with placenta previa had higher Cd concentrations. However, this study was cross-sectional and lacked important information related to Cd concentration, such as detailed smoking habits and sources of Cd intake. In addition, the subjects in this study comprised ordinary pregnant Japanese women, and it was impossible to observe the relationship between a wide range of Cd exposure and placenta previa. Therefore, epidemiological and experimental studies are warranted to verify the relationship between Cd exposure and pregnancy abnormalities.


Assuntos
Metais Pesados/metabolismo , Placenta Acreta/metabolismo , Placenta Prévia/metabolismo , Selênio/metabolismo , Adulto , Estudos Transversais , Feminino , Humanos , Japão , Metais Pesados/sangue , Gravidez , Selênio/sangue
14.
J Dairy Sci ; 102(8): 6781-6789, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31155253

RESUMO

Selenium is included in selenoprotein sequences, which participate in enzymatic processes necessary to preserve optimal health. Some lactic acid bacteria carry out the biotransformation of inorganic selenium in their metabolism. The complete biochemical mechanism of selenium biotransformation is still unknown; however, it is known that both the selenocysteine synthesis process and its subsequent incorporation into selenoproteins include serine as part of the action of seryl-RNAt synthetase. Therefore, the aim of this work was to determine the effect of serine during the biotransformation of selenium and the subsequence growth of Streptococcus thermophilus in a minimal medium. Two culture media were prepared, one enriched with the minimum inhibitory concentration of selenite (as Na2SeO3) and the other as a mixture of the minimum inhibitory concentration of selenite and serine. The absorbed selenium concentration was measured by inductively coupled plasma, and the selenocysteine identification was performed by reverse-phase HPLC. In the second culture medium, decreases in both times, the adaptation and the logarithmic phase, were observed. According to the results, it was possible to establish that the presence of serine allowed the biotransformation of selenite into selenocysteine by Strep. thermophilus.


Assuntos
Meios de Cultura/química , Selênio/metabolismo , Selenocisteína/biossíntese , Serina/administração & dosagem , Streptococcus thermophilus/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Selenoproteínas , Serina/análise
15.
Ecotoxicol Environ Saf ; 180: 179-184, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31082582

RESUMO

Selenium (Se) and zinc (Zn) are necessary mineral nutrients for human body but millions of people have an inadequate intake of them, and eat food enriched with Se and Zn may minimize these problems. Chinese cabbage is an important food in people's daily life. The aim of this study was to evaluate the effects of single Se, Zn and their combination treatment in soil on their accumulation, antioxidant system and lipid peroxidation in roots and leaves of Chinese cabbage using soil pot culture experiment. When 0.5 mg kg-1 Se +30 mg kg-1 Zn and 1.0 mg kg-1 Se +30 mg kg-1 Zn were spiked in soils, Zn concentrations in roots and leaves of Chinese cabbage were significantly increased (p < 0.05) by 20.2%, 37.8% and 17.9%, 34.1% respectively compared to the treatment of 30 mg kg-1 Zn added, and the latter was significantly higher (p < 0.05) than that of former, indicating Se significantly promoted Zn accumulation. Almost all physiological indexes including POD, SOD, CAT, APX, GR, Chlorophyll a, Chlorophyll b, Carotenoids, MDA and Free proline in the treatments of Se or Zn spiked were significantly improved (p < 0.05) or basically unaffected compared to the control without Se or Zn added. The biomass change trends were similar with these indexes either. These results showed that the addition in soil of Se and Zn significantly increased their accumulation in Chinese cabbage without affected its formal growth. Particularly, the addition of Se promoted Zn accumulation. The conclusions were more important reference for the production practice of cash crop enriched of Se and Zn either.


Assuntos
Brassica/efeitos dos fármacos , Selênio/farmacologia , Solo , Zinco/metabolismo , Antioxidantes/metabolismo , Brassica/enzimologia , Brassica/metabolismo , Carotenoides/metabolismo , Clorofila/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/enzimologia , Folhas de Planta/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/enzimologia , Raízes de Plantas/metabolismo , Selênio/metabolismo
16.
Environ Sci Pollut Res Int ; 26(20): 20475-20484, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31102230

RESUMO

The ambiguous mechanism that selenite seems to be absorbed by roots via phosphorus (P) and silicon (Si) transporters signifies P and Si may affect selenite uptake. However, the role of P and Si in phloem-mediated selenium (Se) transport within plant tissue is unknown. Therefore, in this work, tomato (Solanum lycopersicum L.) seedlings were exposed to selenite under different hydroponic conditions firstly. And then, split-root experiments were conducted. Results showed that Se uptake decreased as external pH increased. At pH 8, more selenite in the form of SeO32- was assimilated under P-deficient conditions than under P-normal conditions. Silicate inhibited Se uptake only at pH 3 (27.5% H2SeO3 +72.5% HSeO3-). The results of split-root experiments showed that Se concentrations in seedlings increased under heterogeneously high P or Si. Selenium transport from shoots to roots immersed in solution without selenite was also enhanced. This study illustrated that the affinity of tomato roots to assimilate selenite species followed the order of H2SeO3 >HSeO3- >SeO32-. H2SeO3 was absorbed into roots via Si transporters, whereas HSeO3- and a portion of SeO32- were absorbed via low- and high-affinity P transporters, respectively. In addition, heterogeneously high P or Si concentrations in environmental media could enhance phloem-mediated Se redistribution.


Assuntos
Lycopersicon esculentum/efeitos dos fármacos , Floema/metabolismo , Fosfatos/farmacologia , Ácido Selenioso/farmacocinética , Silicatos/farmacologia , Transporte Biológico/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Hidroponia , Lycopersicon esculentum/metabolismo , Floema/efeitos dos fármacos , Fósforo/farmacologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Plântula/efeitos dos fármacos , Selênio/metabolismo , Selênio/farmacocinética
17.
Food Chem Toxicol ; 130: 187-198, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31078725

RESUMO

Mercury (Hg) is a potent toxicant. In the field of public health a chronic-low-level environmental Hg exposure resulting from fish consumption in general population is still being discussed. The objective of the study was to assess the influence of real Hg exposure on biomarkers of selenium (Se) status and selected biomarkers of pro-oxidant/anti-oxidant effects in healthy men (n = 67) who participated in the short-term intervention study consisting in daily fish consumption for two weeks. The analysis included Se level, Se-associated antioxidants at molecular (profile of 7 genes encoding selected proteins related to antioxidant defense) and biochemical levels (Se-dependent glutathione peroxidases activities and plasma selenoprotein P concentration). A pro-oxidant/anti-oxidant balance was explored using a biomarker of plasma lipid peroxidation and total antioxidant activity. The study revealed significant correlations (p < 0.05) between the biomarkers of exposure to Hg, Se level and Se-dependent antioxidants. Even though the risk of adverse effects of Hg for volunteers was substantially low, biomarkers of Hg altered levels of circulation selenoproteins and their genes expression. Changes in genes expression during study differed between the main enzymes involved in two systems: downregulation of thioredoxin reductase1 and upregulation of glutathione peroxidases. Hg exposure caused imbalance between the biomarkers of pro-oxidant/anti-oxidant effects.


Assuntos
Antioxidantes/metabolismo , Exposição Ambiental , Mercúrio/toxicidade , Selênio/metabolismo , Adulto , Biomarcadores , Dieta , Humanos , Masculino , Pessoa de Meia-Idade , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Adulto Jovem
18.
Environ Sci Pollut Res Int ; 26(17): 17834-17844, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31037530

RESUMO

Selenium (Se) is a vital element which leads to strong antioxidation in animals and humans. However, the mechanism underlying natural cereal Se-induced biological changes is not well understood. This study intended to explore the gene differential expression in naturally aged mice exposed to selenium by RNA-Seq technique. A total spectrum of 53 differentially expressed genes was quantified in mice heart tissues treated with Se-rich and general rice. The GO functional annotation of differentially expressed genes disclosed the enrichment of cellular process, ionic binding, biological regulation, and catalytic activity. One hundred twenty-three differential pathways (cardiovascular diseases, immune system, transport and catabolism, longevity regulating, and PI3K-AKT signaling) were identified according to KEGG metabolic terms. Afterwards, the effect of Se-rich rice on the antioxidant activity was assessed. The selenium-rich diet increased the total antioxidant capacity (T-AOC), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) in mice serum and livers while significantly reduces methane dicarboxylic aldehyde (MDA) contents. FOXO1 and FOXO3 genes, which acted as the regulators of apoptosis and the antioxidant enzyme, were significantly enhanced in mice when fed with Se-rich rice. In short, the present findings disclosed the alluring insights of organic and inorganic selenium sources on certain biological processes and antioxidant activity of living bodies. However, long-term trials are still required to draw a definitive conclusion, including risks and benefit analysis for various management strategies.


Assuntos
Antioxidantes/metabolismo , Oryza/metabolismo , Selênio/metabolismo , Animais , Glutationa Peroxidase/metabolismo , Fígado/metabolismo , Camundongos , Oryza/química , Fosfatidilinositol 3-Quinases/metabolismo , Selênio/análise , Superóxido Dismutase/metabolismo , Transcriptoma/efeitos dos fármacos
19.
Bull Environ Contam Toxicol ; 102(5): 628-634, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31053869

RESUMO

The antagonistic effect between mercury (Hg) and selenium (Se) is conclusively established in animals and human beings in the past decades. However, the underlying mechanisms of the interactions between Hg and Se in plants, as well as the metabolism of Hg-Se compounds in crops are still far from being understood. The botanic metallomics of Hg and Se mainly focuses on the translocation, transformation, and metabolism of Hg and Se in the environmental and botanic systems employing metallomics methods. An adequate understanding of the biological behavior of Hg and Se in plant is beneficial for sequestration of Hg and Se in soil-plant systems with high Hg and Se contamination. It can also provide a molecular mechanistic basis for Se supplementation in Se-deficient areas. Here, the key developments in current understanding of Hg and Se interactions in plants are reviewed. The metabolism and antagonism of Hg and Se in various plants, as well as the advanced analytical methods commonly used in this field, are summarized and discussed. As suggested, plant Hg and Se uptake, metabolism, and antagonism can be taken into account for detoxification and remediation strategies for the reduction of Hg and Se in the food chain.


Assuntos
Produtos Agrícolas/metabolismo , Mercúrio/metabolismo , Selênio/metabolismo , Animais , Cadeia Alimentar , Humanos , Solo
20.
IET Nanobiotechnol ; 13(2): 214-218, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31051453

RESUMO

Selenium (Se) is a rare and essential element for the human body and other living organisms because of its role in the structure of several proteins and having anti-oxidant properties to reduce oxidative stress at cells. Some microorganisms can absorb Se oxyanions and convert them into zero-valent Se (Se0) in the nanoscale dimensions, which can be used for producing Se nanoparticles (SeNPs). In the present study, SeNPs were intracellularly biosynthesised by yeast Nematospora coryli, which is an inexpensive method and does not involve using materials hazardous for human and environment. The produced NPs were refined by a two-phase system and then characterised and identified by ultraviolet-visible, X-ray diffraction, X-ray fluorescence, transmission electron microscope, and Fourier transform infrared spectroscopy analyses. The structural analysis of biosynthesised SeNPs showed spherical-shaped NPs with size ranging from 50 to 250 nm. Also, extracted NPs were applied to explore their anti-candida and anti-oxidant activities. The results of this investigation confirm the biological properties of Se.


Assuntos
Antifúngicos/metabolismo , Antioxidantes/metabolismo , Nanopartículas/química , Saccharomycetales/metabolismo , Selênio/metabolismo , Antifúngicos/química , Antifúngicos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Compostos de Bifenilo/análise , Compostos de Bifenilo/metabolismo , Candida/efeitos dos fármacos , Tamanho da Partícula , Picratos/análise , Picratos/metabolismo , Saccharomycetales/química , Selênio/química
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