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1.
Gene ; 781: 145535, 2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-33631240

RESUMO

Aluminum (Al) toxicity is an important factor in limiting peanut growth on acidic soil. The molecular mechanisms underlying peanut responses to Al stress are largely unknown. In this study, we performed transcriptome analysis of the root tips (0-1 cm) of peanut cultivar ZH2 (Al-sensitive) and 99-1507 (Al-tolerant) respectively. Root tips of peanuts that treated with 100 µM Al for 8 h and 24 h were analyzed by RNA-Seq, and a total of 8,587 differentially expressed genes (DEGs) were identified. GO and KEGG pathway analysis excavated a group of important Al-responsive genes related to organic acid transport, metal cation transport, transcription regulation and programmed cell death (PCD). These homologs were promising targets to modulate Al tolerance in peanuts. It was found that the rapid transcriptomic response to Al stress in 99-1507 helped to activate effective Al tolerance mechanisms. Protein and protein interaction analysis indicated that MAPK signal transduction played important roles in the early response to Al stress in peanuts. Moreover, weighted correlation network analysis (WGCNA) identified a predicted EIL (EIN3-like) gene with greatly increased expression as an Al-associated gene, and revealed a link between ethylene signaling transduction and Al resistance related genes in peanut, which suggested the enhanced signal transduction mediated the rapid transcriptomic responses. Our results revealed key pathways and genes associated with Al stress, and improved the understanding of Al response in peanut.


Assuntos
Alumínio/toxicidade , Arachis/efeitos dos fármacos , Arachis/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Arachis/metabolismo , Mapeamento Cromossômico , Cromossomos de Plantas , Perfilação da Expressão Gênica , Genes de Plantas , Proteínas de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Mapas de Interação de Proteínas , RNA-Seq , Plântula/crescimento & desenvolvimento , Estresse Fisiológico
2.
Mutat Res ; 861-862: 503296, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33551099

RESUMO

Studies on the toxic effects of cooking with aluminum pots are limited and none of them have explored its impact on the genetic material in germ and somatic cells. Therefore, this study investigated the cytogenotoxic effect of boiled water from new, 3- and 6-year old aluminum pots in germ and somatic cells viz-a-vis mouse sperm morphology test and sperm count; and the bone marrow micronucleus test. The mice were allowed to freely drink the boiled water from the different aluminum pots for 3, 4, and 5 weeks. The heavy metal analysis showed that As, Pb, Cd, and Al were present in the boiled water samples at different concentrations with the 6-year old pot having the highest concentrations of Pb, Cd, and Al. There were duration of exposure and age of pot-dependent significant increase in abnormal sperm cells and a significant decrease total mean sperm count of exposed mice. Similarly, there was a statistically significant increase in micronucleated polychromatic erythrocytes and nuclear abnormalities in the exposed mice that increased dependently upon the age of the cookware. Finally there were significantly increased activities of serum AST and ALT; and the liver concentrations of MDA, SOD and CAT in boiled water exposed mice. The findings of this study revealed that boiled water from aluminum pots is capable of inducing cytotoxic and genotoxic effects, especially as the pot ages.


Assuntos
Alumínio/análise , Alumínio/toxicidade , Utensílios de Alimentação e Culinária/estatística & dados numéricos , Culinária/métodos , Dano ao DNA , Espermatozoides/patologia , Animais , Masculino , Camundongos , Reprodução , Espermatozoides/efeitos dos fármacos
3.
Chemosphere ; 271: 129569, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33453483

RESUMO

OBJECTIVE: To explore the effects of occupational aluminium(Al) exposure on workers' cognition through a longitudinal study. METHODS: The study population consisted of 276 workers in an Al factory. In 2014, we used inductively coupled plasma mass spectrometry (ICP-MS) to determine the plasma aluminium (P-Al) concentration of the workers, and a combined questionnaire to test the workers' cognitive function. Followed-up in 2016, the workers were tested again for cognitive function. Generalized linear regression was used to assess the association between P-Al concentration and cognitive scores, and multivariable logistic regression was used to assess the risk of cognitive decline caused by Al exposure. RESULTS: Generalized linear regression results showed that a non-significant association was found between the P-Al concentration and cognitive test scores (P > 0.05) in 2014. Two years later, each 10-fold increase in P-Al concentration was inversely associated with the score of Mini-Mental state examination (MMSE) (ß: -0.53, 95% CI: -0.86, -0.20) and Fuld object memory evaluation (FOME) (ß: -0.93, 95% CI: -1.62, -0.24). Each 10-fold increase in P-Al concentration was inversely associated with MMSE2016-2014 (ß: -0.38, 95% CI: -0.74, -0.01) and FOME2016-2014 (ß: -1.20, 95% CI: -1.95, -0.45). There was a statistically significant difference in the average annual rate of change of MMSE and FOME with the tertile of P-Al concentration increase (P < 0.05). The multivariable logistic regression results showed that as the P-Al concentration increased, the risk of a FOME score decline increased (Ptrend = 0.009). CONCLUSIONS: Continuous occupational Al exposure can damage workers' overall cognitive ability, especially episodic memory function.


Assuntos
Transtornos Cognitivos , Exposição Ocupacional , Alumínio/toxicidade , Cognição , Humanos , Estudos Longitudinais , Testes Neuropsicológicos , Exposição Ocupacional/efeitos adversos
4.
Ecotoxicol Environ Saf ; 207: 111265, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32920313

RESUMO

Aluminum (Al) toxicity is a major yield-limiting factor for crops in acidic soils. In this work, we have investigated the potential role of spermidine (Spd) on Al toxicity in rice chloroplasts. Exogenous Spd markedly reduced Al concentration and elevated other nutrient elements such as Mn, Mg, Fe, K, Ca, and Mo in chloroplasts of Al-treated plants. Meanwhile, Spd further activated arginine decarboxylase (ADC) activity of key enzyme in polyamine (PA) synthesis, and enhanced PA contents in chloroplasts. Spd application dramatically addressed Al-induced chlorophyll (Chl) losses, inhibited thylakoid membrane protein complexes degradation, especially photosystem II (PSII), and significantly depressed the accumulations of superoxide radical (O2·-), hydrogen peroxide (H2O2), and malondialdehyde (MDA) in chloroplasts. Spd addition activated antioxidant enzyme activities and decreased soluble sugar content in chloroplasts compared with Al treatment alone. Spd not only reversed the inhibition of photosynthesis-related gene transcript levels induced by Al toxicity, but diminished the increased expression of Chl catabolism-related genes. Furthermore, Chl fluorescence analysis showed that Spd protected PSII reaction centers and photosynthetic electron transport chain under Al stress, thus improving photosynthetic performance. These results suggest that PAs are involved in Al tolerance in rice chloroplasts and can effectively protect the integrity and function of photosynthetic apparatus, especially PSII, by mitigating oxidative damage induced by Al toxicity.


Assuntos
Alumínio/toxicidade , Complexo de Proteína do Fotossistema II/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Espermidina/farmacologia , Alumínio/metabolismo , Antioxidantes/metabolismo , Clorofila/metabolismo , Cloroplastos/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , Malondialdeído/metabolismo , Fotossíntese/efeitos dos fármacos , Complexo de Proteína do Fotossistema II/metabolismo , Poliaminas/metabolismo , Espermidina/metabolismo
5.
Plant Sci ; 302: 110711, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33288018

RESUMO

To identify unknown regulatory mechanisms leading to aluminium (Al)-induction of the Al tolerance gene ALS3, we conducted an expression genome-wide association study (eGWAS) for ALS3 in the shoots of 95 Arabidopsis thaliana accessions in the presence of Al. The eGWAS was conducted using a mixed linear model with 145,940 genome-wide single nucleotide polymorphisms (SNPs) and the association results were validated using reverse genetics. We found that many SNPs from the eGWAS were associated with genes related to phosphatidylinositol metabolism as well as stress signal transduction, including Ca2+signals, inter-connected in a co-expression network. Of these, PLC9, CDPK32, ANAC071, DIR1, and a hypothetical protein (AT4G10470) possessed amino acid sequence/ gene expression level polymorphisms that were significantly associated with ALS3 expression level variation. Furthermore, T-DNA insertion mutants of PLC9, CDPK32, and ANAC071 suppressed shoot ALS3 expression in the presence of Al. This study clarified the regulatory mechanisms of ALS3 expression in the shoot and provided genetic evidence of the involvement of phosphatidylinositol-derived signal transduction under Al stress.


Assuntos
Transportadores de Cassetes de Ligação de ATP/fisiologia , Alumínio/toxicidade , Proteínas de Arabidopsis/fisiologia , Arabidopsis/genética , Fosfatidilinositóis/metabolismo , Brotos de Planta/metabolismo , Transdução de Sinais , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Arabidopsis/metabolismo , Arabidopsis/fisiologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Estudo de Associação Genômica Ampla , Malatos/metabolismo , Brotos de Planta/fisiologia , Polimorfismo de Nucleotídeo Único/genética , Estresse Fisiológico , Transcriptoma
6.
Environ Toxicol Pharmacol ; 82: 103555, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33309951

RESUMO

Several studies highlight the presence of aluminum and diclofenac in water bodies around the world and their ability to induce oxidative stress and a negative effect on biomolecules in several aquatic species. However, studies evaluating the toxic effect of mixtures of these contaminants are scarce. The objective of this work was to determine the genotoxic, cytotoxic and embryotoxic effect of the mixture of aluminum and diclofenac at environmentally relevant concentrations on Cyprinus carpio. Juveniles of Cyprinus carpio were exposed to 0.31 µg L-1 of diclofenac, 24.45 mg L-1 of aluminum, and a mixture of both contaminants at the same concentrations for 12, 24, 48, 72 and 96 h. After the exposure time the liver, gills and blood were extracted and the following biomarkers were evaluated: micronucleus frequency, comet assay, caspase activity and TUNEL test. On the other hand, Cyprinus carpio embryos were exposed to diclofenac (0.31 µg L-1), aluminum (0.06 mg L-1) and their mixture at the same concentrations and exposure time. Microscopic observation was performed to evaluate embryonic development at 12, 24, 48, 72 and 96 h. Diclofenac (0.31 µg L-1) induces significant increases in micronucleus frequency with respect to control (p < 0.05), in all tissues. Aluminum (24.45 mg L-1) significantly increases DNA damage index in liver and blood cells with respect to control (p < 0.05). All treatments increase caspases activity in all tissues with respect to control (p < 0.05). Diclofenac increases the percentage of TUNEL-positive cells in liver and blood; while aluminum and the mixture increases it significantly in gills and blood with respect to the control (p < 0.05). The mixture significantly delays embryonic development, while aluminum and the mixture significantly increase teratogenic index with respect to control (p < 0.05). In conclusion, exposure to environmental concentrations of aluminium, diclofenac and their mixture induces genotoxic damage, cell death by apoptosis and negative effects on the development of Cyprinus carpio and the toxic response is modified by the interaction of the xenobiotics.


Assuntos
Alumínio/toxicidade , Carpas , Diclofenaco/toxicidade , Mutagênicos/toxicidade , Teratogênios/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Células Sanguíneas/efeitos dos fármacos , Carpas/embriologia , Carpas/genética , Carpas/metabolismo , Caspase 3/metabolismo , Ensaio Cometa , Dano ao DNA , Interações Medicamentosas , Desenvolvimento Embrionário/efeitos dos fármacos , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Testes para Micronúcleos
7.
Toxicol Mech Methods ; 31(1): 53-66, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32972309

RESUMO

Despite the availability of sufficient data on the effects of individual metal exposure on living organisms, a critical knowledge gap still exists in predicting effects of multi-metals particularly on the pituitary-testicular axis. Thus, the aim of the present study was to check the effects of individual or combined (binary and ternary) exposure to aluminum, copper, and zinc on (i) sperm and testosterone levels (ii) oxidative stress and (iii) structural changes in testis of male Wistar rats. Animals were exposed to aluminum, copper, and zinc either individually (20 mg/kg, orally, once, daily), binary (10 mg/kg each, orally, once daily) or in ternary combination (5 mg/kg, each, orally, once daily) for 24 weeks. The exposure to aluminum, copper individually and in combination led to a significant decrease in sperm counts and an increased oxidative stress compared to the control group. Exposure to zinc caused significant decrease in oxidative stress and an increase in different sperm variables. The exposure to zinc with aluminum or copper had no toxic effects on testis while concomitant exposure to aluminum, copper, and zinc produced more pronounced testicular injury. In summary, while co-exposure to zinc with aluminum or copper produced reproductive toxicity the co-exposure to all the three metals may lead to a significant testicular toxicity and these changes were related to increase in oxidative stress in rats.


Assuntos
Alumínio/toxicidade , Cobre/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Testículo/efeitos dos fármacos , Zinco/toxicidade , Animais , Masculino , Ratos Wistar , Reprodução/efeitos dos fármacos , Medição de Risco , Contagem de Espermatozoides , Motilidade Espermática/efeitos dos fármacos , Espermatozoides/metabolismo , Espermatozoides/patologia , Testículo/metabolismo , Testículo/patologia , Testosterona/metabolismo , Fatores de Tempo
8.
Planta ; 253(1): 3, 2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-33346890

RESUMO

MAIN CONCLUSION: Eucalyptus camaldulensis EcDQD/SDH2 and 3 combine gallate formation, dehydroquinate dehydratase, and shikimate dehydrogenase activities. They are candidates for providing the essential gallate for the biosynthesis of the aluminum-detoxifying metabolite oenothein B. The tree species Eucalyptus camaldulensis shows exceptionally high tolerance against aluminum, a widespread toxic metal in acidic soils. In the roots of E. camaldulensis, aluminum is detoxified via the complexation with oenothein B, a hydrolyzable tannin. In our approach to elucidate the biosynthesis of oenothein B, we here report on the identification of E. camaldulensis enzymes that catalyze the formation of gallate, which is the phenolic constituent of hydrolyzable tannins. By systematical screening of E. camaldulensis dehydroquinate dehydratase/shikimate dehydrogenases (EcDQD/SDHs), we found two enzymes, EcDQD/SDH2 and 3, catalyzing the NADP+-dependent oxidation of 3-dehydroshikimate to produce gallate. Based on extensive in vitro assays using recombinant EcDQD/SDH2 and 3 enzymes, we present for the first time a detailed characterization of the enzymatic gallate formation activity, including the cofactor preferences, pH optima, and kinetic constants. Sequence analyses and structure modeling suggest the gallate formation activity of EcDQD/SDHs is based on the reorientation of 3-dehydroshikimate in the catalytic center, which facilitates the proton abstraction from the C5 position. Additionally, EcDQD/SDH2 and 3 maintain DQD and SDH activities, resulting in a 3-dehydroshikimate supply for gallate formation. In E. camaldulensis, EcDQD/SDH2 and 3 are co-expressed with UGT84A25a/b and UGT84A26a/b involved in hydrolyzable tannin biosynthesis. We further identified EcDQD/SDH1 as a "classical" bifunctional plant shikimate pathway enzyme and EcDQD/SDH4a/b as functional quinate dehydrogenases of the NAD+/NADH-dependent clade. Our data indicate that in E. camaldulensis the enzymes EcDQD/SDH2 and 3 provide the essential gallate for the biosynthesis of the aluminum-detoxifying metabolite oenothein B.


Assuntos
Oxirredutases do Álcool , Eucalyptus , Ácido Gálico , Oxirredutases do Álcool/metabolismo , Alumínio/toxicidade , Vias Biossintéticas/fisiologia , Eucalyptus/efeitos dos fármacos , Eucalyptus/enzimologia , Eucalyptus/genética , Ácido Gálico/metabolismo , Hidroliases/metabolismo
9.
Ecotoxicol Environ Saf ; 203: 110999, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32888604

RESUMO

Aluminium (Al) is a key element that plays a major role in inhibiting plant growth and productivity under acidic soils. While lipids may be involved in plant tolerance/sensitivity to Al, the role of monogalactosyldiacylglycerol (MGDG) in Al response remains unknown. In this study, Arabidopsis MGDG synthase (AtMGD) mutants (mgd1, mgd2 and mgd3) and wild-type (Col-0) plants were treated with AlCl3; the effect of aluminium on root growth, aluminium distribution, plasma membrane integrity, lipid peroxidation, hydrogen peroxide content and membrane lipid compositions were analysed. Under Al stress, mgd mutants exhibited a more severe root growth inhibition, plasma membrane integrity damage and lipid peroxidation compared to Col-0. Al accumulation in root tips showed no difference between Col-0 and mutants under Al stress. Lipid analysis demonstrated that under Al treatment the MGDG content in all plants and MGDG/DGDG (digalactosyldiacylglycerol) remarkably reduced, especially in mutants impairing the stability and permeability of the plasma membrane. These results indicate that the Arabidopsis mgd mutants are hypersensitive to Al stress due to the reduction in MGDG content, and this is of great significance in the discovery of effective measures for plants to inhibit aluminium toxicity.


Assuntos
Alumínio/toxicidade , Arabidopsis/efeitos dos fármacos , Galactolipídeos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Poluentes do Solo/toxicidade , Alumínio/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Galactolipídeos/genética , Galactosiltransferases/genética , Galactosiltransferases/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Lipídeos de Membrana/metabolismo , Mutação , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Poluentes do Solo/metabolismo
10.
PLoS One ; 15(8): e0237845, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32813721

RESUMO

Aluminum (Al3+) toxicity is one of the most important limitations to agricultural production worldwide. The overall response of plants to Al3+ stress has been documented, but the contribution of protein phosphorylation to Al3+ detoxicity and tolerance in plants is unclear. Using a combination of tandem mass tag (TMT) labeling, immobilized metal affinity chromatography (IMAC) enrichment and liquid chromatography-tandem mass spectrometry (LC-MS/MS), Al3+-induced phosphoproteomic changes in roots of Tamba black soybean (TBS) were investigated in this study. The Data collected in this study are available via ProteomeXchange with the identifier PXD019807. After the Al3+ treatment, 189 proteins harboring 278 phosphosites were significantly changed (fold change > 1.2 or < 0.83, p < 0.05), with 88 upregulated, 96 downregulated and 5 up-/downregulated. Enrichment and protein interaction analyses revealed that differentially phosphorylated proteins (DPPs) under the Al3+ treatment were mainly related to G-protein-mediated signaling, transcription and translation, transporters and carbohydrate metabolism. Particularly, DPPs associated with root growth inhibition or citric acid synthesis were identified. The results of this study provide novel insights into the molecular mechanisms of TBS post-translational modifications in response to Al3+ stress.


Assuntos
Alumínio/toxicidade , Fosfoproteínas/metabolismo , Proteínas de Plantas/metabolismo , Proteômica , Soja/metabolismo , Citratos/metabolismo , Fosforilação/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Biossíntese de Proteínas/efeitos dos fármacos , Mapas de Interação de Proteínas/efeitos dos fármacos , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Soja/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Transcrição Genética/efeitos dos fármacos
12.
J Plant Res ; 133(5): 625-637, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32562161

RESUMO

Styrax camporum Pohl. (Styracaceae) is a woody species that grows on acidic soils from the Brazilian savanna with high aluminum (Al) saturation (m% > 50%), where it accumulates ~ 1500 mg Al per kg dry leaves. Using nutrient solution, a previous study showed that 1480 µM Al causes toxicity symptoms, which raises the question whether less than 1480 µM Al could cause beneficial effects on this species. Here, we checked possible altered gas exchange rates, damage to organelles in root tips and the association between Al exposure and mitochondria occurrence in cells of root tips, once organic acids from Krebs cycle exuded by the roots of this species when exposed to Al have been recently evidenced. Five-month-old plants were grown in nutrient solution with 0, 740 and 1480 µM Al for 90 days. Plants exposed to 1480 µM Al showed less developed root system, reduced plant height and low gas exchange rates in relation to those exposed to 0 and 740 µM Al, confirming that 1480 µM Al is toxic to S. camporum. However, plants exposed to 0 and 740 µM Al had similar number of leaves, plant height, root biomass, root length, total plant biomass and gas exchange rates, indicating that no beneficial effects from 740 µM Al could be noted on this species. In plants exposed to 0 and 740 µM Al, mitochondria were noted at the root tip, while at 1480 µM Al these organelles were not evident due to the conspicuous vacuolation of root cells. S. camporum shows limited tolerance to Al in nutrient solution. In addition, this species is not dependent on Al to grow and develop because the plants grew well under 0 and 740 µM Al.


Assuntos
Alumínio , Styrax , Alumínio/toxicidade , Brasil , Raízes de Plantas , Styrax/efeitos dos fármacos , Styrax/crescimento & desenvolvimento , Madeira
13.
Environ Res ; 188: 109734, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32544722

RESUMO

Aluminum and mercury are environmentally ubiquitous. Individually they are both neurotoxic elements with shared neuro-pathogenic pathways: oxidative stress, altered neurotransmission, and disruption of the neuroendocrine and immune systems. In the infant, Al and Hg differ in type of exposure, absorption, distribution (brain access), and metabolism. In environmentally associated exposure (breast milk and infant formulas) their co-occurrences fluctuate randomly, but in Thimerosal-containing vaccines (TCVs) they occur combined in a proprietary ratio; in these cases, low-doses of Thimerosal-ethylmercury (EtHg) and adjuvant-Al present the most widespread binary mixture in less developed countries. Although experimental studies at low doses of the binary Hg and Al mixture are rare, when studied individually they have been shown to affect neurological outcomes negatively. In invitro systems, comparative neurotoxicity between Al and Hg varies in relation to the measured parameters but seems less for Al than for Hg. While neurotoxicity of environmental Hg (mainly fish methyl-Hg, MeHg) is associated with neurobehavioral outcomes in children, environmental Al is not associated, except in certain clinical conditions. Therefore, the issues of their neurotoxic effects (singly or combined) are discussed. In the infant (up to six months) the organic-Hg and Al body burdens from a full TCV schedule are estimated to reach levels higher than that originating from breastfeeding or from high aluminum soy-based formulas. Despite worldwide exposure to both Al and Hg (inorganic Hg, MeHg, and Thimerosal/EtHg), our knowledge on this combined exposure is insufficient to predict their combined neurotoxic effects (and with other co-occurring neurotoxicants).


Assuntos
Mercúrio , Compostos de Metilmercúrio , Vacinas , Alumínio/toxicidade , Animais , Carga Corporal (Radioterapia) , Criança , Feminino , Humanos , Lactente , Mercúrio/toxicidade , Leite Humano , Síndromes Neurotóxicas/epidemiologia , Timerosal/toxicidade
14.
Aquat Toxicol ; 224: 105484, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32380302

RESUMO

One of the consequences of global mining is the exposure of metals into the environment, caused by the rupture of tailings dams. Excess of metals, such as aluminum (Al) and manganese (Mn) can cause serious damage to fauna and flora. The presence of these metals, associated with the temperature increase that occurs nowadays can potentially increase biochemical and metabolic rates in plant tissues and may affect growth. Therefore, the objective of this work was to evaluate the toxicity of the metals Al and Mn into the biomass' growth of the macrophyte Ricciocarpos natans, under two temperatures (25 and 27 °C). R. natans individuals (n = 10 ± 0.5 cm wide) were exposed during 30 days to Al (1.5; 2.5 and 5.0 mg L-1) and Mn (0.7; 1.5 and 3.0 mg L-1) at temperatures and photoperiod-controlled germination chambers. Fresh macrophyte masses were determined gravimetrically to determine the kinetic growth using a logistic model. With that, it was noticed that the presence of Al interfered negatively in the increase of the R. natans biomass, mainly in the highest concentrations and at 27 °C. Mn, on the other hand, affected the increase in biomass, mainly in the highest concentration. As a result, the growth coefficients (µ) changed, being up to 4 times lower in the Al bioassays and up to 2 times higher than the control in the Mn bioassays. However, the dry R. natans biomass individuals that were exposed to the treatments was reduced when compared to the control, except for the lower concentration of Mn. These results contribute to the understanding of the environmental changes that can occur due to metals contained in mining tailings in aquatic ecosystems and the influence of global warming on the metabolic processes of the growth of aquatic macrophytes.


Assuntos
Alumínio/toxicidade , Temperatura Alta , Hydrocharitaceae/crescimento & desenvolvimento , Manganês/toxicidade , Rios/química , Poluentes Químicos da Água/toxicidade , Alumínio/metabolismo , Biomassa , Brasil , Ecossistema , Monitoramento Ambiental , Hydrocharitaceae/metabolismo , Manganês/metabolismo , Mineração , Poluentes Químicos da Água/metabolismo
15.
Chemosphere ; 251: 126642, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32345545

RESUMO

The ubiquitous presence of aluminum in the environment leads to a high likelihood of human exposure. Neurotoxicity of the trivalent cationic form of this metal (Al3+) occurs in the central nervous system via accumulation of Al in cells of neural origin, including neural progenitor cells (NPCs). NPCs play a key role in the development and regeneration of the brain throughout life; therefore, this metal may contribute to neuropathological conditions. Here, we evaluated the effects of different Al3+ concentrations (0-50 µM) on the purinergic system of NPCs isolated from embryonic telencephalons, cultured as neurospheres. Al3+ adhered to the cell surface of neurospheres reducing extracellular ATP release, as well as ATP, ADP, and AMP hydrolysis by NTPDase and 5'-nucleotidase, respectively. In addition, impaired nucleotide release by Al3+ reduced P2Y1 and adenosine A2A receptors expression in differentiated neurospheres. These receptors are crucial for NPC proliferation during brain development and self-repair against external stimuli, such as metal exposure. Thus, Al3+ represents an environmental agent linked to neurodegeneration through alterations in the ATP-signalling pathway, proving to be a potential mechanism associated with NPC proliferation and brain degeneration.


Assuntos
Alumínio/toxicidade , 5'-Nucleotidase , Trifosfato de Adenosina/metabolismo , Alumínio/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Sistema Nervoso Central/metabolismo , Proteínas Ligadas por GPI , Humanos , Transdução de Sinais/efeitos dos fármacos , Células-Tronco , Testes de Toxicidade
16.
Sheng Wu Gong Cheng Xue Bao ; 36(3): 529-540, 2020 Mar 25.
Artigo em Chinês | MEDLINE | ID: mdl-32237546

RESUMO

To explore the effects of some chemical amendments on the plant growth and phytoextraction efficiencies of cadmium (Cd)/zinc (Zn) hyper accumulator Sedum plumbizincicola in acid soils with high aluminum (Al) toxicity, a greenhouse pot experiment was conducted. Different kinds and dosages of amendments including calciummagnesium-phosphorus fertilizer (CMP), magnesium carbonate (MgCO3), potassium dihydrogen phosphate (KH2POPO4 ) were added. The results showed that CMP and MgCO3 increased soil pH and decreased soil exchangeable Al concentration to some extent, while KH2PO4 reduced soil exchangeable Al concentration but had little effect on increasing soil pH. Proper application (9.39 mg/kg) of CMP could improve the biomass and Cd and Zn phytoextraction efficiencies by S. plumbizincicola but it would inhibit plant growth and phytoextraction performance when exceeding 9.39 mg/kg. MgCO3 addition enhanced plant metal uptake while KH2PO4 presented an opposite effect. It suggests that using CMP and MgCO3 could alleviate Al toxicity to S. plumbizincicola in acid soils and maintain relatively high metal extraction efficiency.


Assuntos
Alumínio , Cádmio , Fertilizantes , Sedum , Poluentes do Solo , Zinco , Alumínio/toxicidade , Biodegradação Ambiental , Cádmio/metabolismo , Sedum/efeitos dos fármacos , Sedum/metabolismo , Solo/química , Poluentes do Solo/metabolismo , Poluentes do Solo/toxicidade , Zinco/metabolismo
17.
Chemosphere ; 249: 126449, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32208217

RESUMO

Influence of floc breakage and re-growth on the release of natural dissolved organic matter (DOM) and dissolved Al was explored. Results indicated that Al species including monomeric species (Ala), medium polymer species (Alb), and colloidal or solid species (Alc) in polyaluminum chlorides (PACls) played significant role. At lower doses ranged from 5 to 20 mg/L, floc breakage damaged Ala-NOM bonds for AlCl3, causing obvious release of DOM and dissolved Al. After re-growth, dissolved Al mainly connected with broken flocs, rather than released DOM. Thus, after re-growth, DOM release was still remarkable, but additional removal of dissolved Al was observed. At higher doses above 20 mg/L, more Ala transformed to Alb and Alc. Due to the enmeshment effect induced by Alc coagulation, fewer DOM and dissolved Al were released after breakage, and additional removal of DOM and dissolved Al were attained after re-growth. For PAClAl13 which mainly contained Alb, at optimal dose, floc breakage generated the most severe release of DOM and dissolved Al, while the result after re-growth was just reverse. This was ascribed to stronger charge neutralization ability of Alb. Furthermore, the influence of floc breakage and re-growth on DOM and dissolved Al for PAClC was similar to that for AlCl3. The reason was fully analyzed in this research. This study may give further indication regarding reaction mechanisms of floc breakage and re-growth for PACls.


Assuntos
Alumínio/toxicidade , Eliminação de Resíduos Líquidos/métodos , Hidróxido de Alumínio/toxicidade , Cloretos , Floculação , Polímeros/química
18.
Artigo em Inglês | MEDLINE | ID: mdl-32155754

RESUMO

Aluminium (Al) is a non-essential neurotoxicant and there is limited information regarding exposure to Al in utero. This study sought to evaluate the in utero exposure to Al in urban South African women, its effects on birth outcomes and possible synergistic effects between Al, essential and neurotoxic elements such as lead (Pb), mercury (Hg) and arsenic (As), as well as a a potential sex-dependent response to these elements in neonates. This study has found elevated levels of Al in urban women at delivery. The Spearman's rank correlation coefficients (p-value) of the association between maternal serum Al and birth outcomes (gestational age and parity), and between maternal serum Al and Cu, Zn and Se, were statistically significant. However, in the general and the stratified models, no association was found between any of the birth outcomes and maternal serum Al. The association between maternal serum Al and neurotoxic elements at delivery showed a significant positive correlation for Pb only (rho = 0.361; p < 0.001) which was found to be sex-dependent in neonates (males, rho = 0.285; p < 0.004 and females, rho = 0.444, p < 0.001). Our preliminary findings indicate that in utero exposure to Al is an emerging concern requiring further research and directives from public health authorities.


Assuntos
Alumínio , Arsênico , Mercúrio , Oligoelementos , Adulto , Alumínio/toxicidade , Arsênico/toxicidade , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Masculino , Exposição Materna , Mercúrio/toxicidade , Gravidez , Resultado da Gravidez , Oligoelementos/toxicidade , Adulto Jovem
19.
Sultan Qaboos Univ Med J ; 20(1): e63-e70, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32190371

RESUMO

Objectives: Infant formulas are useful alternatives to breast milk in many circumstances but may pose health risks to infants and children due to contamination by potentially toxic metals. This study aimed to determine the aluminium, arsenic and mercury concentrations and carry out an exposure health risk assessment in commonly consumed infant formulas in Nigeria. Methods: Different brands of both locally manufactured and imported infant formulas were purchased in March 2017 from stores in Port Harcourt, Nigeria. Analysis of metals in the samples was performed by atomic absorption spectrophotometry. The health risk was assessed by comparing estimated daily intake of aluminium, arsenic and mercury with the provisional tolerable daily intake acceptable by the Joint Food and Agricultural Organization/World Health Organization Expert Committee on Food Additives (JECFA). Results: A total of 26 infant formulas were analysed. The levels of arsenic were higher in cereal-based formulas compared to milk-based formulas, but the difference was not significant (P >0.05). The intake levels of aluminium, arsenic and mercury in infant formulas were found to be 8.02-14.2%, 437.1-771% and 23.7-41.8% of the provisional tolerable daily intake JECFA threshold values, respectively. Conclusion: Commonly consumed infant formulas in Nigeria may add to the body burden of arsenic in children.


Assuntos
Alumínio/análise , Arsênico/análise , Contaminação de Alimentos/análise , Fórmulas Infantis/análise , Mercúrio/análise , Alumínio/toxicidade , Arsênico/toxicidade , Humanos , Lactente , Fórmulas Infantis/toxicidade , Recém-Nascido , Mercúrio/toxicidade , Nigéria , Saúde Pública , Medição de Risco
20.
Environ Pollut ; 261: 114230, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32220755

RESUMO

Polyphenols, pivotal secondary metabolites, are involved in plant adaption to abiotic stresses. Here, we investigated the role and metabolism profile of polyphenols under aluminum (Al) stress in different lettuce genotypes grown in 0.5 mM CaCl2 solution with AlCl3 (pH = 4.5). The complementary use of high-resolution mass spectrometry and quantitative biochemical approaches allowed the characterization of total and unique phenols, as well as their roles in Al tolerance. By comparing the most tolerant and sensitive genotype, 8 polyphenols, including 4 phenolic acids, 2 flavonoids, 1 xanthone and 1 unknown compound, were identified in the roots of the tolerant genotype. The total phenolic and flavonoid contents significantly increased in the tolerant genotype under Al stress. Seedlings with more phenolic accumulation usually performed greater Al tolerance. Meanwhile, principal enzymes related to phenolic biosynthesis significantly increased in roots of the tolerance genotype after Al treatment, with phenylalanine ammonia lyase (PAL), cinnamate 4-hydroxylase, and 4-coumarate coenzyme A ligase increased by 16, 18 and 30%, respectively. The elevated total phenolics were significantly suppressed by AIP, a highly specific PAL inhibitor. Consequently, the antioxidant capacity was inhibited, leading to lettuce sensitivity to Al stress. These results clearly suggested the enhancement of unique polyphenolic biosynthesis as an adaptive strategy of lettuce to Al stress by protecting plants from oxidative stress.


Assuntos
Alumínio , Alface , Polifenóis , Estresse Fisiológico , Alumínio/toxicidade , Alface/efeitos dos fármacos , Raízes de Plantas/metabolismo , Polifenóis/metabolismo , Poluentes do Solo/toxicidade , Estresse Fisiológico/fisiologia
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