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1.
Ecotoxicol Environ Saf ; 208: 111643, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396163

RESUMO

Sulfur (S) can play essential roles in protecting plants against abiotic stress, including heavy metal toxicity. However, the effect of this nutrient on plants exposed to barium (Ba) is still unknown. This study was designed to evaluate the S supply on oxidative stress and the antioxidant system of Tanzania guinea grass under exposure to Ba, grown in a nutrient solution under greenhouse conditions. It was studied the influence of S/Ba combinations in nutrient solution on oxidative stress indicators (hydrogen peroxide, malondialdehyde, and proline) and antioxidant enzyme activities (superoxide dismutase, catalase, ascorbate peroxidase, guaiacol peroxidase, and glutathione reductase). The treatments consisted in thirteen S/Ba combinations in the nutrient solution (0.1/0.0; 0.1/5.0; 0.1/20.0; 1.0/2.5; 1.0/10.0; 1.9/0.0 - control; 1.9/5.0; 1.9/20.0; 2.8/2.5; 2.8/10.0; 3.7/0.0; 3.7/5.0 and 3.7/20.0 mM of S and Ba, respectively). The plants were grown for two growth periods, which consisted of fourteen days of S supply and the eight days of Ba exposure each one. The severe S deficiency decreased the superoxide dismutase activity, regardless of Ba exposure in recently expanded leaves and culms plus sheaths. However, supplemental S supply (above 1.9 mM S, which corresponds to S supply adequate to plant growth) it improved the superoxide dismutase activity in these tissues under high Ba concentrations. Conversely, the severe S deficiency increased the activities of catalase, ascorbate peroxidase, and glutathione reductase in grass leaves slightly, without Ba exposure influence. It was observed that the supplemental S supply also induced the guaiacol peroxidase activity and proline production in culms plus sheaths under high Ba rates, showing values until 2.5 and 3.1 folds higher than the control treatment, respectively. In plants under exposure to 20.0 mM Ba, the supplemental S supply decreased the malondialdehyde content in culms plus sheaths in 17% compared to 1.9 mM S. These results indicate that supplemental S supply can mitigate Ba toxicity in Tanzania guinea grass, mainly by improving superoxide dismutase and guaiacol peroxidase activities, and proline metabolism.


Assuntos
Antioxidantes/metabolismo , Bário/toxicidade , Panicum/efeitos dos fármacos , Prolina/metabolismo , Enxofre/farmacologia , Fertilizantes , Estresse Oxidativo/efeitos dos fármacos , Panicum/crescimento & desenvolvimento , Panicum/metabolismo , Peroxidase/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Superóxido Dismutase/metabolismo
2.
Int J Food Microbiol ; 330: 108713, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-32512363

RESUMO

Sodium metabisulfite (SMBS), potassium metabisulfite (PMBS), aluminum sulfate (AlS) and aluminum potassium sulfate (AlPS), common sulfur-containing salts used as food additives, were evaluated for their antifungal activity against Penicillium digitatum, Penicillium italicum and Geotrichum citri-aurantii, the most economically important pathogens causing postharvest diseases of citrus fruits. In vitro radial mycelial growth was measured on potato dextrose agar (PDA) Petri dishes amended with five different concentrations of the salts (10, 20, 30, 50, 100 mM) after 7 d of incubation at 25 °C. SMBS and PMBS at all concentrations, and AIS and AIPS above 20 mM, completely inhibited the growth of these fungi. The curative antifungal activity of the four salts to control citrus green (GM) and blue (BM) molds and sour rot (SR) was evaluated on 'Valencia' oranges artificially inoculated in rind wounds with P. digitatum, P. italicum and G. citri-aurantii, respectively. In vivo primary screenings showed no significant antifungal activity of AlS and AlPS to control the three diseases at any dose tested, but SMBS and PMBS reduced the incidence and severity of GM, BM and SR at various concentrations. Effective salts and concentrations were selected for in vivo dip treatments in small-scale trials. Dips at room temperature (20 °C) in SMBS and PMBS at 20 and 50 mM for 60 or 120 s significantly reduced the incidence and severity of GM and BM, with PMBS at 50 mM for 120 s the most effective treatment. Conversely, dips in SMBS and PMBS at 50 mM for 60 or 120 s did not reduce SR incidence and severity. SMBS and PMBS treatments are potentially new tools to be included in reduced-risk non-polluting strategies to control Penicillium diseases, but not SR, on citrus fruits.


Assuntos
Antifúngicos/farmacologia , Citrus/microbiologia , Aditivos Alimentares/farmacologia , Doenças das Plantas/prevenção & controle , Enxofre/farmacologia , Aditivos Alimentares/química , Conservação de Alimentos/métodos , Frutas/microbiologia , Fungos/efeitos dos fármacos , Fungos/crescimento & desenvolvimento , Doenças das Plantas/microbiologia , Temperatura , Fatores de Tempo
3.
Cell Prolif ; 53(5): e12821, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32364266

RESUMO

OBJECTIVES: Photodynamic therapy (PDT) is a promising approach for cancer treatment, and the underlying signalling pathway changes has been carried out for studying the PDT mechanisms, but is majorly limited to organic photosensitizers (PSs). For the emerging nano-PSs typically possessing higher 1 O2 quantum yield, few mechanistic studies were carried out, which limited their further applications in clinical therapeutics. PI3K/Akt signalling pathway, a most frequently activated signalling network in cancers, could promote cancer cell survival, but was seldom reported in previous PDT studies mediated by nano-PSs. MATERIALS AND METHODS: Sulphur doped carbon dots (S-CDs) was prepared via a hydrothermal synthetic route and was characterized by transmission electron microscopy, X-ray photoelectron spectroscopy and so on. CCK-8 assay and Annexin V/PI staining were performed to demonstrate the death of cancer cells, Western blot, RT-PCR and immunofluorescence were employed to explore the underlying mechanism, and variation of PI3K/Akt and other signalling pathways was detected by Western blot. RESULTS: S-CDs was successfully synthesized, and it was much more efficient compared with classic organic PSs. S-CDs could induce cancer cell death through mitochondria mediated cell apoptosis with the imbalance of Bcl-2 family proteins and caspase cascade via several signalling pathways. Low concentration of S-CDs could effectively inhibit PI3K/Akt pathway and promote p38/JNK pathway, on one way inhibiting cancer cell survival and on the other way promoting cell apoptosis. CONCLUSIONS: Herein, we found that S-CDs acted as an inhibitor of the PI3K/Akt pathway for efficient cancer cell killing, thus yielding in a higher PDT performance over the existing photosensitizers.


Assuntos
Carbono/farmacologia , Neoplasias/tratamento farmacológico , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Enxofre/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Neoplasias/metabolismo , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo
4.
Cell Prolif ; 53(4): e12786, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32301195

RESUMO

OBJECTIVES: Photodynamic therapy (PDT) is a novel non-invasive therapeutic method, which has been widely applied for the treatment of human oral cancers. However, the problems of undesirable singlet oxygen (1 O2 ) quantum yields and long-term phototoxicity were inevitable during the application of traditional photosensitizers. Therefore, it is necessary to explore novel photosensitizers for the improvement of therapeutic effects. In our study, the sulphur-doped carbon dots (S-CDs) of high yield of singlet oxygen (1 O2 ) were synthesized as a nano-photosensitizer for OSCC to improve the PDT efficacy in clinical practice. MATERIALS AND METHODS: After synthesis of the novel S-CDs, the size, morphologic characteristics, surface potential and yield of singlet oxygen (1 O2 ) were determined. In vitro study was performed to compare the therapeutic effect as well as the biocompatibility of the novel S-CDs to those of 5-ALA. Besides, possible mechanism of action was illustrated. RESULTS: After synthesis of the novel S-CDs, the size, morphologic characteristics, surface potential and yield of singlet oxygen (1 O2 ) were determined. In vitro study was performed to compare the therapeutic effect as well as the biocompatibility of the novel S-CDs to those of 5-ALA. Besides, possible mechanism of action was illustrated. CONCLUSIONS: These data from the in vitro study demonstrated the promising safety profile of the low dose (nmol/L) S-CDs, which indicated the novel S-CDs could be used as a promising photodynamic agent for oral cancer therapy.


Assuntos
Carbono/farmacologia , Carcinoma de Células Escamosas/tratamento farmacológico , Neoplasias Bucais/tratamento farmacológico , Fármacos Fotossensibilizantes/farmacologia , Enxofre/farmacologia , Apoptose/efeitos dos fármacos , Carbono/química , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Humanos , Modelos Moleculares , Neoplasias Bucais/patologia , Nanopartículas/química , Nanopartículas/ultraestrutura , Fotoquimioterapia , Fármacos Fotossensibilizantes/química , Enxofre/química
5.
Ecotoxicol Environ Saf ; 191: 110242, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32004945

RESUMO

A novel green approach was utilized to fabricate sulfur nanoparticles (SNPs) with the aid of Ocimum basilicum leaves extract. The effective formation of the synthesized SNPs was examined and approved using UV-visible spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier transform infrared (FT-IR) spectroscopy. The average particle size was 23 nm with spherical shape and crystalline in nature. In the pot experiment, the synthesized SNPs were applied with different concentrations (12.5, 25, 50, 100 and 200 µM) as pre-soaking to Helianthus annuus seeds and irrigated with 100 mM MnSO4. As a result of manganese (Mn) exposure, the harvested 14-day sunflower seedlings showed a significant decline in the growth parameters (shoot length, leaf area and the relative water content of both shoot and root), photosynthetic pigments, mineral content (N, P, K, Ca, and Mg), and protein content compared to the control. The root length, electrolyte leakage, Na and Mn levels, metabolites content (amino acids, protein, glycine betaine, proline, and cysteine) were greatly raised as affected by Mn stress. Mn toxicity reduction using SNPs was demonstrated, as the medium doses enhanced seedlings growth, photosynthetic pigments, and mineral nutrients. Application of SNPs decreased Mn uptake and enhanced S metabolism through increasing cysteine level. Likewise, SNPs elevated seedlings water content and eliminated physiological drought via increasing osmolytes such as amino acids and proline. It can be concluded that green-synthesized SNPs had the potential to limit the deleterious effects of Mn stress.


Assuntos
Helianthus , Manganês/toxicidade , Nanopartículas/química , Ocimum basilicum/química , Enxofre/farmacologia , Química Verde , Helianthus/efeitos dos fármacos , Helianthus/crescimento & desenvolvimento , Tamanho da Partícula , Fotossíntese/efeitos dos fármacos , Extratos Vegetais/química , Folhas de Planta/química , Prolina/metabolismo , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Enxofre/química , Água/metabolismo
6.
Ecotoxicol Environ Saf ; 191: 110200, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31958629

RESUMO

Cadmium (Cd) contamination in paddy soils and the related pollution risk of rice grain have received increasing attention. Agronomic measures, such as the application of sulfur and changes in water regimes, were reported to mitigate the accumulation of Cd in rice. However, there is limited information on the combined effects of sulfur application and water regimes. Therefore, a pot experiment was conducted to investigate the effects of two sulfur forms, three water regimes and multiple sulfur application rates on Cd accumulation in rice. The sulfur was applied as SO42- (SVI, replacing the traditional fertilizers by SO42--containing fertilizers), and element S (S0) was applied at 0, 10, 20, 30 and 40 mg S kg-1 soil. The water regimes were continuous flooding (F), flooding-moist alternation (FM), and moist irrigation (M), for a total of 30 treatments. The results indicated that application of SVI exceeding 30 mg S kg-1 significantly reduced the Cd concentrations in brown rice by 31.1-56.3%, and the Cd concentrations decreased with increasing amount of irrigation water. Similar reductions in Cd concentrations in rice shoots and rice straw collected at tillering and maturity stages were observed after application of SVI. However, the effect of S0 application on Cd accumulation in grain was not significant under different water regimes. Furthermore, this study found that application of both SVI and S0 inhibited the transfer of Cd from rice roots to shoots in most cases. These findings indicate that replacing traditional fertilizers with SO42--containing fertilizers, especially combined with increased irrigation, could be a potential approach to mitigate Cd accumulation in rice growing in Cd-contaminated acidic paddy soils.


Assuntos
Cádmio/metabolismo , Oryza/metabolismo , Poluentes do Solo/metabolismo , Sulfatos/farmacologia , Enxofre/farmacologia , Fertilizantes , Oryza/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Solo/química , Água
7.
Int J Mol Med ; 45(3): 931-938, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31894268

RESUMO

Insulin­like growth factor­1 (IGF­1) regulates cell growth, glucose uptake and protein metabolism, and is required for growth hormone (GH) signaling­mediated insulin production and secretion. IGF1 expression is associated with STAT5, which binds to a region (TTCNNNGAA) of the gene. Although sulfur is used in various fields, the toxicity of this element is a significant disadvantage as it causes indigestion, vomiting, diarrhea, pain and migraine. Therefore, it is difficult to conduct in vitro experiments to directly determine the effects of dietary sulfur. Additionally, it is difficult to dissolve non­toxic sulfur (NTS). The present study aimed to identify the role of NTS in GH signaling as a Jak2/STAT5b/IGF­1 pathway regulator. MTT assay was used to identify an optimum NTS concentration for C2C12 mouse muscle cells. Western blotting, RT­PCR, chromatin immunoprecipitation, overexpression and small interfering RNA analyses were performed. NTS was dissolved in 1 mg/ml DMSO and could be used in vitro. Therefore, the present study determined whether NTS induced mouse muscle cell growth via GH signaling. NTS notably increased STAT5b binding to the Igf1 promoter. NTS also promoted GH signaling by upregulating GH receptor expression, similar to GH treatment. NTS enhanced GH signaling by regulating Jak2/STAT5b/IGF­1 signaling pathway factor expression in C2C12 mouse muscle cells. Thus, NTS may be used as a GH­enhancing growth stimulator.


Assuntos
Hormônio do Crescimento/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Janus Quinase 2/metabolismo , Fator de Transcrição STAT5/metabolismo , Enxofre/farmacologia , Animais , Linhagem Celular , Camundongos , Transdução de Sinais/efeitos dos fármacos
8.
Chemosphere ; 240: 124846, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31550594

RESUMO

Cadmium (Cd) precipitation and dissolution in pore water is associated with dissolved organic carbon (DOC)-induced reduction-oxidation of sulfur (S) under waterlogging and is vital for controlling the bioavailability in paddy soil. A 120-day soil incubation experiment, including application of sulfur (S, 30 mg kg-1) and wheat straw (W, 1.0%) alone or in combination (W + S) into Cd-contaminated paddy soil under waterlogging, was conducted to investigate the dynamic of dissolved Cd and its relationship with DOC, S2-, Fe2+, pH, Eh and pe + pH in soil pore water. The results showed that the lowest dissolved Cd concentration was observed in the W + S-treated soil pore water among all treatments when the soil Eh remained at lower values during the period of 15-60 days of incubation, which could be attributed to CdS precipitation and/or co-precipitation of Cd absorbed by FeS2 because of the reduction in sulfur. The application of S resulted in a Cd rebound in the pore water irrespective of W addition when the Eh began to increase from its lowest values during the period of 45-75 days of incubation, and SOB genera were observed in the S added soil. This could be attributed to re-dissolution of the precipitated Cd in soils under the SOB-driven oxidation of sulfide such as CdS and FeS2. In conclusion, DOC-driven reduction-oxidation of sulfur controls Cd dissolution in the pore water of Cd-contaminated paddy soil under waterlogging conditions. Further studies are required to investigate the interaction of sulfur and SOM-induced DOC on Cd bioavailability in rice-planted paddy soils.


Assuntos
Cádmio/uso terapêutico , Poluição Ambiental/efeitos adversos , Poluentes do Solo/química , Enxofre/uso terapêutico , Cádmio/farmacologia , Enxofre/farmacologia , Água
9.
Phytochemistry ; 170: 112213, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31786408

RESUMO

Clutia lanceolata Forssk. (C. lanceolata) is a medicinal plant native to sub-Saharan Africa and the Arabian Peninsula. Phytochemical investigation of the aerial parts of C. lanceolata yielded twenty-one coumarins including methylthio and methylsulfinyl-coumarins. Thirteen of these compounds are reported here for the first time, named as cluteolin A to M. The remaining eight compounds are known but have not been associated previously with C. lanceolata. The structures of the undescribed compounds were elucidated from their 2D NMR and MS spectra. Single crystal X-ray analyses confirmed the structures of eleven compounds. As, in Saudi Arabian tradition, C. lanceolata has been reported to have anti-diabetic and anti-fungal properties, the coumarins were examined for their biological activity. Seven compounds strongly enhanced the glucose-triggered release of insulin by murine pancreatic islets, with two compounds showing more than two-fold enhancement of insulin secretion, compared with the standard drug glimepiride.


Assuntos
Cumarínicos/farmacologia , Euphorbiaceae/química , Secreção de Insulina/efeitos dos fármacos , Insulina/metabolismo , Compostos Fitoquímicos/farmacologia , Enxofre/farmacologia , Animais , Cumarínicos/química , Cumarínicos/isolamento & purificação , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação , Arábia Saudita , Enxofre/química , Enxofre/isolamento & purificação
10.
Sci Rep ; 9(1): 14883, 2019 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-31619759

RESUMO

Control of common scab disease can be reached by resistant cultivars or suppressive soils. Both mechanisms are likely to translate into particular potato microbiome profiles, but the relative importance of each is not known. Here, microbiomes of bulk and tuberosphere soil and of potato periderm were studied in one resistant and one susceptible cultivar grown in a conducive and a suppressive field. Disease severity was suppressed similarly by both means yet, the copy numbers of txtB gene (coding for a pathogenicity determinant) were similar in both soils but higher in periderms of the susceptible cultivar from conducive soil. Illumina sequencing of 16S rRNA genes for bacteria (completed by 16S rRNA microarray approach) and archaea, and of 18S rRNA genes for micro-eukarytes showed that in bacteria, the more important was the effect of cultivar and diversity decreased from resistant cultivar to bulk soil to susceptible cultivar. The major changes occurred in proportions of Actinobacteria, Chloroflexi, and Proteobacteria. In archaea and micro-eukaryotes, differences were primarily due to the suppressive and conducive soil. The effect of soil suppressiveness × cultivar resistance depended on the microbial community considered, but differed also with respect to soil and plant nutrient contents particularly in N, S and Fe.


Assuntos
Actinobacteria/crescimento & desenvolvimento , Archaea/crescimento & desenvolvimento , Suscetibilidade a Doenças/imunologia , Doenças das Plantas/microbiologia , Microbiologia do Solo , Solanum tuberosum/microbiologia , Actinobacteria/classificação , Actinobacteria/genética , Actinobacteria/patogenicidade , Archaea/classificação , Archaea/genética , Archaea/patogenicidade , Chloroflexi/classificação , Chloroflexi/genética , Chloroflexi/crescimento & desenvolvimento , Chloroflexi/patogenicidade , Produtos Agrícolas , Resistência à Doença/efeitos dos fármacos , Células Eucarióticas/metabolismo , Técnicas de Genotipagem , Ferro/metabolismo , Ferro/farmacologia , Microbiota/genética , Nitrogênio/metabolismo , Nitrogênio/farmacologia , Doenças das Plantas/imunologia , Proteobactérias/classificação , Proteobactérias/genética , Proteobactérias/crescimento & desenvolvimento , Proteobactérias/patogenicidade , RNA Ribossômico 16S/genética , RNA Ribossômico 18S/genética , Solanum tuberosum/efeitos dos fármacos , Solanum tuberosum/imunologia , Enxofre/metabolismo , Enxofre/farmacologia , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
11.
Ecotoxicol Environ Saf ; 184: 109641, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31518827

RESUMO

The objective of this study was to investigate the responses of cadmium (Cd) availability and transfer in the soil-rice system to added sulfur (S) under unstable pe + pH conditions. Different water management conditions (flooding and aerobic treatments) cause changes in the soil pe + pH. We conducted a pot experiment to investigate the influence of S supply on soil Cd availability and Cd accumulation in rice plants (Oryza sativa L.), using three water regimes (continuous dryness, alternating dry-wet for one cycle, and continuous flooding) combined with two S concentrations (0 and 300 mg/kg). The results showed that the flooding treatment was more effective in decreasing soil pe + pH, Cd availability, and Cd accumulation in rice tissues than were the aerobic treatments. S-induced reduction in Cd uptake and translocation in rice was attributed to the decreased soil pe + pH values and enhanced biosynthesis of phytochelatins (PCs) and glutathione (GSH) in rice roots. Microscopic examination showed that the flooding treatment with added soil S resulted in better rice root growth. Element dispersive spectrometer (EDS) analysis indicated that S addition and flooding treatment promoted the formation of iron plaques and increases in Fe concentration in rice tissues. Conversely, partial disintegration of the root epidermis was observed in the dry treatment without added S.


Assuntos
Cádmio/análise , Oryza/metabolismo , Poluentes do Solo/análise , Solo/química , Enxofre/farmacologia , Cádmio/metabolismo , Glutationa/biossíntese , Concentração de Íons de Hidrogênio , Ferro/análise , Oryza/efeitos dos fármacos , Oryza/crescimento & desenvolvimento , Fitoquelatinas/biossíntese , Poluentes do Solo/metabolismo
12.
BMC Genomics ; 20(1): 628, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31370780

RESUMO

BACKGROUND: Free asparagine is the precursor for acrylamide formation during cooking and processing of grains, tubers, beans and other crop products. In wheat grain, free asparagine, free glutamine and total free amino acids accumulate to high levels in response to sulphur deficiency. In this study, RNA-seq data were acquired for the embryo and endosperm of two genotypes of bread wheat, Spark and SR3, growing under conditions of sulphur sufficiency and deficiency, and sampled at 14 and 21 days post anthesis (dpa). The aim was to provide new knowledge and understanding of the genetic control of asparagine accumulation and breakdown in wheat grain. RESULTS: There were clear differences in gene expression patterns between the genotypes. Sulphur responses were greater at 21 dpa than 14 dpa, and more evident in SR3 than Spark. TaASN2 was the most highly expressed asparagine synthetase gene in the grain, with expression in the embryo much higher than in the endosperm, and higher in Spark than SR3 during early development. There was a trend for genes encoding enzymes of nitrogen assimilation to be more highly expressed in Spark than SR3 when sulphur was supplied. TaASN2 expression in the embryo of SR3 increased in response to sulphur deficiency at 21 dpa, although this was not observed in Spark. This increase in TaASN2 expression was accompanied by an increase in glutamine synthetase gene expression and a decrease in asparaginase gene expression. Asparagine synthetase and asparaginase gene expression in the endosperm responded in the opposite way. Genes encoding regulatory protein kinases, SnRK1 and GCN2, both implicated in regulating asparagine synthetase gene expression, also responded to sulphur deficiency. Genes encoding bZIP transcription factors, including Opaque2/bZIP9, SPA/bZIP25 and BLZ1/OHP1/bZIP63, all of which contain SnRK1 target sites, were also expressed. Homeologues of many genes showed differential expression patterns and responses, including TaASN2. CONCLUSIONS: Data on the genetic control of free asparagine accumulation in wheat grain and its response to sulphur supply showed grain asparagine levels to be determined in the embryo, and identified genes encoding signalling and metabolic proteins involved in asparagine metabolism that respond to sulphur availability.


Assuntos
Asparagina/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genótipo , Enxofre/farmacologia , Triticum/genética , Triticum/metabolismo , Análise de Sequência de RNA , Fatores de Transcrição/genética , Triticum/efeitos dos fármacos , Triticum/enzimologia
13.
Redox Biol ; 26: 101293, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31421411

RESUMO

Sulfane sulfur species including hydrogen polysulfide and organic persulfide are newly recognized normal cellular components, and they participate in signaling and protect cells from oxidative stress. Their production has been extensively studied, but their removal is less characterized. Herein, we showed that sulfane sulfur at high levels was toxic to Escherichia coli under both anaerobic and aerobic conditions. OxyR, a well-known regulator against H2O2, also sensed sulfane sulfur, as revealed via mutational analysis, constructed gene circuits, and in vitro gene expression. Hydrogen polysulfide modified OxyR at Cys199 to form a persulfide OxyR C199-SSH, and the modified OxyR activated the expression of thioredoxin 2 and glutaredoxin 1. The two enzymes are known to reduce sulfane sulfur to hydrogen sulfide. Bioinformatics analysis indicated that OxyR homologs are widely present in bacteria, including obligate anaerobic bacteria. Thus, the OxyR sensing of sulfane sulfur may represent a preserved mechanism for bacteria to deal with sulfane sulfur stress.


Assuntos
Proteínas de Escherichia coli/genética , Escherichia coli/fisiologia , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Proteínas Repressoras/genética , Enxofre/metabolismo , Cromatografia Líquida , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/metabolismo , Perfilação da Expressão Gênica , Peróxido de Hidrogênio/metabolismo , Sulfeto de Hidrogênio/metabolismo , Mutação , Oxirredução , Proteínas Repressoras/química , Proteínas Repressoras/metabolismo , Enxofre/farmacologia , Espectrometria de Massas em Tandem , Tiorredoxinas/metabolismo , Ativação Transcricional
14.
Eur J Med Chem ; 180: 486-508, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31330449

RESUMO

From many decades, S-heterocycles have maintained their status as an important part and core of FDA approved drugs and medicinally active compounds. With exhaustive exploration of nitrogen heterocycles in medicinal chemistry, researchers have shifted their interest towards other heterocycles, especially, S-heterocycles. Thus several attempts have been made to synthesize a variety of new sulphur containing compounds with high medicinal value and low toxicity profile, in comparison to previous N-heterocycles. Till today, S-heterocycle containing compounds have been largely reported as anticancer, antidiabetic, antimicrobial, antihypertension, antivral, antinflammatory etc. In this review, the authors have tried to provide a critical analysis of synthesis and medicinal attributes of sulphur containing heterocycles such as thiirane, thiophene, thiazole, thiopyran, thiazolidine etc reported within last five years to emphasize the significance and usefulness of these S-heterocycles in the drug discovery process.


Assuntos
Compostos Heterocíclicos/farmacologia , Enxofre/farmacologia , Animais , Anti-Infecciosos/síntese química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Anti-Inflamatórios/síntese química , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Anti-Hipertensivos/síntese química , Anti-Hipertensivos/química , Anti-Hipertensivos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Química Farmacêutica , Compostos Heterocíclicos/síntese química , Compostos Heterocíclicos/química , Humanos , Hipoglicemiantes/síntese química , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Enxofre/química
15.
Chemosphere ; 234: 346-355, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31228836

RESUMO

Land application of sewage sludge has received significant attention in recent years but the presence of elevated heavy metals in the sludge limits its land application. The purposes of this study were to investigate the effects of sulfur dosage and inoculum size on the thermophilic bioleaching of heavy metals from sewage sludge in a pilot-scale bioreactor. The microbial communities in this thermophilic bioleaching process were also identified using real-time polymerase chain reaction (real-time PCR). The results showed that the oxidation of sulfur and metal solubilization decreased with the increasing sulfur dosage. When the sulfur dosage was greater than 2% (w/v), the sulfur oxidation and metal solubilization rates decreased, indicating that the thermophilic bioleaching was hindered by high levels of substrate. However, it was found that the efficiency of metal solubilization and solid degradation was increased with the increase of inoculum size in the range from 5% to 20%. At the end of bioleaching, the efficiency of Mn, Zn, Ni, Cu and Cr from the sewage sludge reached 73-100%, 51-60%, 38-52%, 17-43% and 1-38%, respectively, while SS and VSS were degraded by 33-48% and 47-67%, respectively. Based on the analysis of real-time PCR, Sulfobacillus acidophilus was observed to be the predominant species (13-67% of total bacteria), whereas the populations of Sulfobacillus thermosulfidooxidans and Acidithiobacillus caldus were accounted relatively low (<1%).


Assuntos
Inoculantes Agrícolas , Metais Pesados/isolamento & purificação , Esgotos/química , Enxofre/farmacologia , Acidithiobacillus/metabolismo , Bactérias/metabolismo , Reatores Biológicos , Concentração de Íons de Hidrogênio , Metais Pesados/análise , Oxirredução , Projetos Piloto , Esgotos/microbiologia , Enxofre/análise , Eliminação de Resíduos Líquidos/métodos
16.
Ecotoxicol Environ Saf ; 180: 656-667, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31136876

RESUMO

Owing to the active use of rare-earth elements in many areas, it is necessary to study their behavior in the environment and their biological impact on plants. Despite the role of melatonin and sulfur in plant growth, development and abiotic stress tolerance; it is still not clear how they have a strong regulatory influence and synergistic effect on growth, physiological and biochemical characteristics of plants under different environmental stresses. Therefore, this study highlights how melatonin and sulfur together potentially involved in a reversal of lanthanum-inhibited photosynthetic and growth responses in tomato seedlings. Here, we reported that seedlings grown in a medium containing 150 µM lanthanum exhibited increased overproduction of reactive oxygen species (ROS) and lipid peroxidation together with increased Chlorophyll degradation, and activity of chlorophyllase, proline dehydrogenase and glycolate oxidase (GOx), and decreased photosynthesis and growth. However, the application of melatonin and sulfur showed significant responses on tomato seedlings, although the response of their combined treatment was more effective by further increasing photosynthesis and growth under lanthanum toxicity. Melatonin supplied with sulfur suppressed ROS formation, lipid peroxidation and activity of GOx, and increased photosynthesis by upregulating activities of carbonic anhydrase and ribulose-1,5-bisphosphate carboxylase/oxygenase. Also, sulfur supplementation with melatonin to seedlings resulted in an elevation in the accumulation of Chl and proline by increasing δ-aminolevulinic acid and activity of δ-aminolevulinic acid dehydratase and Δ1-pyrroline-5-carboxylate synthetase activity. The administration of melatonin with sulfur substantially induced upregulation of enzymes (superoxide dismutase, ascorbate peroxidase, monodehydroascorbate reductase, dehydroascorbate reductase and glutathione reductase) activities involved in the antioxidant system, thereby mitigating ROS-induced oxidative damage. Thus, this study provides strong evidence that melatonin and sulfur have strong regulatory influence and synergistic role in alleviating the adverse effect of lanthanum-toxicity by increasing photosynthesis and growth.


Assuntos
Poluentes Ambientais/toxicidade , Lantânio/toxicidade , Lycopersicon esculentum/efeitos dos fármacos , Melatonina/farmacologia , Enxofre/farmacologia , Antioxidantes/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Lycopersicon esculentum/crescimento & desenvolvimento , Lycopersicon esculentum/metabolismo , Fotossíntese/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/metabolismo
17.
Sci Rep ; 9(1): 7397, 2019 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-31089197

RESUMO

Supplying exogenous sulfur-rich compounds increases the content of glutathione(GSH) and phytochelatins(PCs) in plant tissues, enabling plants to enhance their cellular defense capacity and/or compartmentalize Cadmium(Cd) into vacuoles. However, the mechanism by which surplus S modulates tolerance to Cd stress in different tissues need further investigation. In the present study, we found that supplementing the tartary buckwheat(Fagopyrum tararicum) exposed to Cd with surplus S reversed Cd induced adverse effects, and increased Cd concentrations in roots, but decreased in leaves. Further analysis revealed that exogenous S significantly mitigated Cd-induced oxidative stress with the aids of antioxidant enzymes and agents both in leaves and roots, including peroxidase(POD), ascorbate peroxidase(APX), glutathione peroxidase(GPX), glutathione S-transferase(GST), ascorbic acid(AsA), and GSH, but not superoxide dismutase(SOD) and catalase(CAT). The increased Cd uptake in root vacuoles and decreased translocation in leaves of exogenous S treated plants could be ascribed to the increasing Cd binding on cell walls, chelation and vacuolar sequestration with helps of non-protein thiols(NPT), PCs and heavy metal ATPase 3(FtHMA3) in roots, and inhibiting expression of FtHMA2, a transporter that helps Cd translocation from roots to shoots. Results provide the fundamental information for the application of exogenous S in reversal of heavy metal stress.


Assuntos
Cádmio/metabolismo , Fagopyrum/efeitos dos fármacos , Fertilizantes , Poluentes do Solo/metabolismo , Enxofre/farmacologia , Cádmio/análise , Cádmio/toxicidade , Fagopyrum/química , Fagopyrum/fisiologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Glutationa/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Peroxidases/metabolismo , Fitoquelatinas/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Brotos de Planta/química , Brotos de Planta/metabolismo , Poluentes do Solo/toxicidade , Vacúolos/química , Vacúolos/metabolismo
18.
Bioorg Chem ; 87: 516-522, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30928874

RESUMO

A new series of ß-aminochalcogenides were designed and synthesized to identify new carbonic anhydrase activator (CAA) agents as novel tools for the management of several neurodegenerative and metabolic disorders which represent a clinical challenge without effective therapies available. Some ß-aminoselenides and ß-aminotellurides showed effective CA activating effects and a potent antioxidant activity. CAAs may have applications for memory therapy and CA deficiency syndromes.


Assuntos
Aminas/farmacologia , Antioxidantes/farmacologia , Anidrases Carbônicas/metabolismo , Selênio/farmacologia , Enxofre/farmacologia , Telúrio/farmacologia , Aminas/química , Antioxidantes/química , Relação Dose-Resposta a Droga , Humanos , Isoenzimas/metabolismo , Estrutura Molecular , Selênio/química , Relação Estrutura-Atividade , Enxofre/química , Telúrio/química
19.
Artigo em Inglês | MEDLINE | ID: mdl-30912480

RESUMO

Urinary tract infections (UTIs) have been frequently reported from different parts of the world. The current knowledge on distribution of causative agents of urinary infections and antibiotics susceptibility pattern is essentially required. In the present study, total 351 uropathogenic bacteria were isolated; among them most prevalent were Escherichia coli (75%), followed by Pseudomonas aeruginosa (8%), Proteus mirabilis (6%), Klebsiella pneumoniae (4%), Staphylococcus aureus (4%) and Enterococcus faecalis (3%). Most isolates of uropathogenic bacteria showed resistance to amoxicillin and trimethoprim, followed by chloramphenicol and kanamycin. Biosynthesis of sulfur nanoparticles (SNPs) was performed by co-precipitation method using sodium thiosulfate in presence of Catharanthus roseus leaf extract. The characterization data showed that SNPs were polydispersed, spherical in shape with size range of 20-86 nm and having negative zeta potential of -9.24 mV. The potential antibacterial activity was observed for SNPs alone and in combination with antibiotics particularly amoxicillin and trimethoprim against majority of the uropathogens. The synergistic effect yielded increase in fold area with high activity index against tested uropathogens. Based on overall results, it can be recommended to use SNPs for the management of UTI alone and also in combination with antibiotics.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Nanopartículas/química , Enxofre/farmacologia , Infecções Urinárias/microbiologia , Antibacterianos/química , Sinergismo Farmacológico , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Humanos , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/isolamento & purificação , Testes de Sensibilidade Microbiana , Proteus mirabilis/efeitos dos fármacos , Proteus mirabilis/isolamento & purificação , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/isolamento & purificação , Enxofre/química
20.
J Hazard Mater ; 373: 212-223, 2019 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-30921572

RESUMO

To reduce pressure of toxic metals on crop plants, several strategies are being employed of which nutrient management is gaining much importance. Moreover, whether nitric oxide (NO), has any role in nutrients-mediated management/amelioration of metal toxicity is still not known. Therefore, the role of Ca and S in managing Cr(VI) toxicity was investigated in tomato and brinjal with an emphasis on possible involvement of NO. Cr(VI) reduced growth in both vegetables which was accompanied by increased accumulation of Cr(VI), lignin and reactive oxygen species (ROS), and altered cell cycle dynamics and photochemistry of photosynthesis. However, external addition of either Ca or S reversed these effects and hence improved growth noticed in both vegetables. Cr(VI) toxicity was further increased by NG-nitro-l-arginine methyl ester even with additional Ca and S while sodium nitroprusside either restored growth up to the control level or increased it in both vegetables, even in the presence of L-NAME, suggesting that NO might have a positive role in nutrients-mediated management/amelioration of Cr(VI) toxicity. In this study, role of Ca, S and NO with reference to Cr(VI) and NO accumulation, components of phenylpropanoid pathway, cell cycle dynamics, photosynthesis, ROS and antioxidant potential in managing Cr(VI) toxicity is discussed.


Assuntos
Cálcio/farmacologia , Cromo/toxicidade , Lycopersicon esculentum/efeitos dos fármacos , Óxido Nítrico/metabolismo , Solanum melongena/efeitos dos fármacos , Enxofre/farmacologia , Ciclo Celular/efeitos dos fármacos , Produtos Agrícolas/efeitos dos fármacos , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/metabolismo , Lycopersicon esculentum/crescimento & desenvolvimento , Lycopersicon esculentum/metabolismo , Fotossíntese/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Solanum melongena/crescimento & desenvolvimento , Solanum melongena/metabolismo
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