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1.
Pestic Biochem Physiol ; 165: 104559, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32359558

RESUMO

Spiders are found among the most important predators of plague insects of numerous agricultural systems. They are the most numerous representatives of the Class Arachnid and are widely distributed in numerous ecosystems. Due to multiple variables, living beings are exposed to quantitative transitions of their energetic reserves, which affect their sensitivity before the different xenobiotics. In the present study we evaluate the effect of cypermethrin (pyrethroid) on different metabolic/energetic stages of the spider Polybetes pythagoricus (Sparassidae). We firstly studied LD50 of cypermethrin on young, males and, pre-vitellogenic and post-vitellogenic females. The activity of superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), glutathione-S-transferase (GST) and acetylcholinesterase (AChE) was analyzed. Results indicate that young have a higher caloric content compared to adults, females have a higher caloric content than males and vitellogenesis generates a great calory decrease in females. The LD50 was significantly lower in young (10%) (103 ng/g weight) in relation to the three models of adults (969-1108 ng/g weight). Vitellogenesis causes an increase of free radicals as a result of the different metabolic processes which manifest as an increase in the lipid peroxidation. Doses at the LD30 and LD40 levels of cypermethrin did not generate alterations in any of the enzymes analyzed in young, this fact may probably provoke an increase of lipid peroxidation (evaluated as a great MDA increase). The activity of the enzymes linked to oxidative stress was altered by this doses in the three adult models, the enzymatic activity CAT, GR, and GST was sex-dependent. Post-vitellogenic females showed a greater activity of CAT, SOD, GST and GR before the xenobiotics than pre-vitellogenic ones, probably as a consequence of metabolic stress generated during vitellogenesis.


Assuntos
Piretrinas , Aranhas , Animais , Antioxidantes , Catalase , Ecossistema , Feminino , Glutationa , Glutationa Peroxidase , Glutationa Transferase , Peroxidação de Lipídeos , Masculino , Estresse Oxidativo , Superóxido Dismutase
2.
Phys Chem Chem Phys ; 22(15): 7942-7951, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32232288

RESUMO

A pharmacophoric motif decorated with supramolecular functionalities (TZT) was designed for potential interaction with biological targets. Main insights of this work include the correlation of supra functionalities of TZT with its binding ability to proteins leading to the modulation of their structure and bioactivity as a promising perspective in the field of cellular protection from oxidative stress. To investigate the role of TZT in obliterating oxidative stress at a molecular level, its binding propensity with bovine serum albumin (BSA) and bovine liver catalase (BLC) was characterized using various biophysical methods. The binding constants of TZT with BSA (Kb = 2.09 × 105 M-1) and BLC (Kb = 2.349 × 105 M-1) indicate its considerable interaction with these proteins. TZT efficiently triggers favourable structural changes in BLC, thereby enhancing its enzyme activity in a dose dependent manner. The enzyme kinetics parameters of TZT binding to BLC were quantified using the Michaelis-Menten model. Both in silico and experimental results suggest that an increased substrate availability could be the reason for enhanced BLC activity. Furthermore, physiological relevance of this interaction was demonstrated by investigating the ability of TZT to attenuate oxidative stress. Treatment with TZT was found to mitigate the inhibition of A549 cell proliferation in the presence of high concentrations of vitamin C. This finding was confirmed at a molecular level by PARP cleavage status, demonstrating that TZT inhibits apoptotic cell death induced by oxidative stress.


Assuntos
Catalase/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Tiazolidinas/farmacologia , Células A549 , Animais , Antioxidantes/farmacologia , Bovinos , Proliferação de Células/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Humanos
3.
J Appl Oral Sci ; 28: e20190583, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32267380

RESUMO

BACKGROUND: Genetic and epigenetic changes have been associated with periodontitis in various genes; however, little is known about genes involved in epigenetic mechanisms and in oxidative stress. OBJECTIVE: This study aims to investigate the association of polymorphisms C677T in MTHFR (rs1801133) and -149C→T in DNMT3B (rs2424913), as well as the methylation profiles of MTHFR, miR-9-1, miR-9-3, SOD1, and CAT with periodontitis. The association between polymorphisms and DNA methylation profiles was also analyzed. METHODOLOGY: The population studied was composed of 100 nonsmokers of both sexes, divided into healthy and periodontitis groups. Genomic DNA was extracted from the epithelial buccal cells, which were collected through a mouthwash. Polymorphism analysis was performed through polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), while methylation-specific PCR (MSP) or combined bisulfite restriction analysis techniques were applied for methylation analysis. RESULTS: For DNMT3B, the T allele and the TT genotype were detected more frequently in the periodontitis group, as well as the methylated profile on the miR-9-1 promoter region. There was also a tendency towards promoter region methylation on the CAT sequence of individuals with periodontal disease. CONCLUSION: The polymorphism -149C→T in DNMT3B (rs2424913) and the methylated profile of the miR-9-1 promoter region are associated with periodontitis.


Assuntos
DNA (Citosina-5-)-Metiltransferases/genética , Metilação de DNA/genética , MicroRNAs/genética , Periodontite/genética , Polimorfismo Genético , Adulto , Idoso , Estudos de Casos e Controles , Catalase/genética , Feminino , Estudos de Associação Genética , Genótipo , Humanos , Masculino , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Superóxido Dismutase-1/genética
4.
An Acad Bras Cienc ; 92(1): e20180596, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32267305

RESUMO

Red cabbage (Brassica oleracea L. var. capitata f. rubra DC.) extract has been demonstrated hypolipidemic and antioxidant capacity. Herein, we investigated the effect of red cabbage aqueous extract (RC) or fenofibrate (FF) in oxidative stress induced by Triton WR-1339 in rats. The antioxidant capacity was evaluated through the superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) activities and, thiobarbituric reactive species (TBARS) and protein carbonyl (PC) levels in erythrocytes, liver, kidneys, cerebral cortex and hippocampus of male rats. The alterations promoted by Triton WR-1339 in enzymatic antioxidant defense in the liver, kidneys and hippocampus were reversed by RC or FF treatments. The TBARS and PC levels increased in the liver, cerebral cortex and hippocampus of hyperlipidemic rats were decreased by the treatments with RC or FF. These findings demonstrated that RC is a potential therapy to treat diseases not only involving dyslipidemic condition but also oxidative stress.


Assuntos
Antioxidantes/farmacologia , Brassica/química , Peroxidação de Lipídeos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Catalase/efeitos dos fármacos , Glutationa Peroxidase/efeitos dos fármacos , Masculino , Oxirredução , Ratos , Ratos Wistar , Superóxido Dismutase , Substâncias Reativas com Ácido Tiobarbitúrico
5.
Mutat Res ; 850-851: 503152, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32247560

RESUMO

The aim of the present study was to assess the oxidative stress level and chromosomal damage induced by occupational exposure to low dose ionizing radiation (LDIR). Two hundred and eighteen hospital workers occupationally exposed to LDIR were included in this study, along with 118 healthy age- and gender-comparable controls. Occupational dosimetry records were collected over the last year and revealed that the accumulated annual dose for each hospital worker was below the permissible limit of the International Commission on Radiological Protection (ICRP). The individuals' oxidative and antioxidative status were determined by measuring the activities of copper zinc-superoxide dismutase (CuZn-SOD), glutathione peroxidase (GSH-Px), catalase (CAT) enzymes, and the levels of malondialdehyde (MDA) in erythrocytes. The effect of radiation on chromosomal integrity was measured by the frequency of micronuclei (MN) formation using the cytokinesis block technique. Our results showed that the activities of CuZn-SOD and CAT enzymes and MDA levels observed in the hospital workers were higher than those in the controls (p < 0.05). We did not find significant difference in GSH-Px enzyme activity between the two groups (p = 0.247). A higher frequency of MN was found in exposed groups than in the controls [3(1-5) ‰ versus 2(0.75-4) ‰; p<0.001]. The difference was significant for males (p = 0.012), but not females (p = 0.14). Multiple linear regression analysis showed differences in the oxidant activities and MN frequency between hospital workers and controls adjusted for age, gender, smoking status and drinking status. Correlation analysis indicated that the frequency of MN was positively associated with MDA levels (p < 0.05). Altogether, these results support the detrimental effects of chronic low dose radiation in humans, which involves the induction of oxidative stress and chromosomal damage.


Assuntos
Antioxidantes/metabolismo , Aberrações Cromossômicas/efeitos da radiação , Exposição Ocupacional/efeitos adversos , Estresse Oxidativo/efeitos da radiação , Adulto , Antioxidantes/efeitos da radiação , Catalase/sangue , Feminino , Glutationa Peroxidase/sangue , Hospitais , Humanos , Masculino , Malondialdeído/sangue , Registros Médicos , Pessoa de Meia-Idade , Doses de Radiação , Radiação Ionizante , Radiometria , Superóxido Dismutase-1/sangue
6.
Ecotoxicology ; 29(4): 444-458, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32189147

RESUMO

Soils can be contaminated with substances arising from anthropogenic sources, but also with natural bioactive compounds produced by plants, such as terpenes and flavonoids. While terpenes and flavonoids have received much less attention from research studies than metals, the effects that phytocompounds can have on soil organisms such as beneficial microorganisms should not be neglected. Herein we report the sole and combined exposure of Rhizobium to cadmium, to the monoterpene alpha-pinene and to the flavanol quercetin. A range of environmentally relevant concentrations of the phytocompounds was tested. Physiological (growth, protein content and intracellular Cd concentration), oxidative damage (lipid peroxidation, protein carbonylation) and antioxidant mechanisms (superoxide dismutase, catalase, glutathione, glutathione-S-transferases, protein electrophoretic profiles) were assessed. Results suggest that exposure to both phytocompounds do not influence Rhizobium growth, but for combined exposure to phytocompounds and Cd, different responses are observed. At low concentrations, phytocompounds seem to relieve the stress imposed by Cd by increasing antioxidant responses, but at high concentrations this advantage is lost and membrane damage may even be exacerbated. Thus, the presence of bioactive phytocompounds in soil may influence the tolerance of microorganisms to persistent toxicants, and may change their impact on the environment.


Assuntos
Monoterpenos Bicíclicos/toxicidade , Cádmio/toxicidade , Quercetina/toxicidade , Rhizobium/efeitos dos fármacos , Poluentes do Solo/toxicidade , Antioxidantes/metabolismo , Biodegradação Ambiental , Catalase/metabolismo , Glutationa/metabolismo , Peroxidação de Lipídeos , Rhizobium/fisiologia , Superóxido Dismutase/metabolismo , Testes de Toxicidade
7.
Acta Cir Bras ; 35(1): e202000103, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32215464

RESUMO

PURPOSE: To investigate the protective effect of Ganoderma lucidum on testicular torsion/detorsion (T/D)-induced ischemia-reperfusion (I/R) injury. METHODS: Thirty male Wistar albino rats were randomly categorized into 3 groups: Group 1: sham, Group 2 ( T/D): 2,5 hours of ischemia and 7 days of reperfusion, Group 3 (T/D+ G. lucidum ): 2,5 hours of ischemia and 7 days of reperfusion and 7 days of 20 mg/kg via gastric gavage G. lucidum polysaccharides per day. Biochemical assays of Malondialdehyde (MDA), superoxide dismutase (SOD), Catalase (CAT), Glutathione (GSH) levels , histopathology and expression levels of VEGF and Bcl-2 with immunohistochemical methods were examined in testicular tissue. RESULTS: G. lucidum treatment was found to have prevented the T/D-induced I/R injury by decreasing MDA levels of the testis. SOD, CAT and GSH activities were decreased in group 2, while they were increased in group 3 (p<0.001) and significant improvement in the tube diameter was observed in group 3. Bcl-2-positive germinal cells were lowered in group 3 compared to the group 2. VEGF expression showed an increase in group 2, whereas it decreased in group 3. CONCLUSION: The antioxidant G. lucidum is thought to induce angiogenesis by reducing the apoptotic effect in testicular torsion-detorsion.


Assuntos
Antioxidantes/uso terapêutico , Reishi/química , Traumatismo por Reperfusão/prevenção & controle , Torção do Cordão Espermático/complicações , Testículo/irrigação sanguínea , Animais , Antioxidantes/farmacologia , Catalase/metabolismo , Avaliação Pré-Clínica de Medicamentos , Masculino , Malondialdeído/metabolismo , Distribuição Aleatória , Ratos , Ratos Wistar , Traumatismo por Reperfusão/etiologia , Torção do Cordão Espermático/metabolismo , Superóxido Dismutase/metabolismo , Testículo/efeitos dos fármacos , Testículo/patologia , Fator A de Crescimento do Endotélio Vascular/metabolismo
8.
Life Sci ; 250: 117554, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32184123

RESUMO

BACKGROUND: Mental stress (MS) is related to endothelial dysfunction in overweight/obese men. It is believed that the pro-oxidant profile, associated with an imbalance in the vascular remodeling process, may contribute to deleterious effects of MS on endothelial function. However, it is unknown whether administration of ascorbic acid (AA), a potent antioxidant, can prevent oxidative and remodeling dysfunction during MS in these subjects. METHODS: Fourteen overweight/obese grade I men (27 ± 7 years; 29.7 ± 2.6 kg·m-2) underwent the Stroop Color Word Test for 5 min to induce MS after AA (3 g) or placebo (PL, 0.9% NaCl) intravenous infusions. Venous blood samples were collected at baseline and the last minute of MS to measure nitrite concentration (chemiluminescence), protein carbonylation, thiobarbituric acid reactive substances (TBARS) and catalase activity (colorimetric assays), superoxide dismutase (SOD; immunoenzymatic assay), activities of active/inactive (pro) forms of metalloproteinases-9 and -2 (MMP; zymography) and its respective tissue inhibitors concentration (TIMP-1 and TIMP-2; immunoenzymatic assays). RESULTS: At baseline, MMP-9 activity (p < 0.01), the MMP-9/proMMP-9 ratio (p = 0.02) and TIMP-1 concentration (p = 0.05) were reduced, whereas proMPP-9 activity was increased (p = 0.02) after AA compared to PL infusion. After PL infusion, MS increased protein carbonylation (p < 0.01), catalase (p < 0.01), and the MMP-9/proMMP-9 ratio (p = 0.04) when compared to baseline. AA infusion reduced protein carbonylation (p = 0.02), MMP-9 activity (p < 0.01), and MMP-9/pro-MMP-9 ratio (p < 0.01), while SOD (p = 0.04 vs baseline), proMPP-9 (p < 0.01 vs PL), MMP-2 (p < 0.01 vs PL) and TIMP-2 (p = 0.02 vs baseline) remained elevated during MS. CONCLUSIONS: AA appears to minimize the oxidative imbalance and vascular remodeling induced by MS.


Assuntos
Ácido Ascórbico/farmacologia , Obesidade/psicologia , Sobrepeso/psicologia , Estresse Psicológico , Remodelação Vascular/efeitos dos fármacos , Adulto , Antioxidantes/metabolismo , Catalase/metabolismo , Estudos Cross-Over , Endotélio Vascular/patologia , Humanos , Luminescência , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Oxidantes/metabolismo , Carbonilação Proteica , Fatores de Risco , Teste de Stroop , Superóxido Dismutase/metabolismo , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Inibidor Tecidual de Metaloproteinase-2/metabolismo , Adulto Jovem
9.
Ecotoxicol Environ Saf ; 193: 110365, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32114244

RESUMO

The biochemical responses of Bellamya aeruginosa as a dominant and widespread freshwater gastropod throughout China to waterborne cadmium (Cd) were investigated to explore the impacts of exposure concentration and duration in this potential sentinel species. After the 7 days' test of dosage-mortality relationship, gastropods were exposed for either 7 days at the LC50 (1.7 mg/L), the LC10 (0.7 mg/L) and 0.02 mg/L Cd, or 28 days at 0.02 mg/L Cd. A suite of biochemical indicators including metallothionein-like protein (MTLP), reduced glutathione (GSH), catalase (CAT), contents of tissue metal (Cd, Fe, Mn, Cu, Zn), and the compartments of these metals bound to MTLP were examined. The treatment of 0.02 mg/L Cd led to the increase of Cd bound to MTLP (Cd-MTLP) levels, the decrease of GSH content, and the upregulation of CAT activity, but no induction of MTLP, indicating that the intrinsic MTLP and GSH worked together for the detoxification of Cd at the low exposure. When the exposure concentration increased, GSH was depleted severely and synthesis of MTLP was triggered, leading to a strong and significant relationship between MTLP level and Cd accumulation. At the lethal concentrations (1.7 mg/L), both MTLP induction and CAT activity were inhibited while the proportion of Cd-MTLP to total Cd were increased, suggesting more intrinsic MTLP were utilized to sequester free Cd ions. Therefore, the content of Cd-MTLP in digestive glands of B. aeruginosa was recommended as a reliable biomarker for Cd contamination.


Assuntos
Cádmio/toxicidade , Gastrópodes/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Cádmio/farmacocinética , Catalase/metabolismo , Biomarcadores Ambientais , Água Doce , Gastrópodes/metabolismo , Glutationa/metabolismo , Metalotioneína/metabolismo , Metais/metabolismo , Poluentes Químicos da Água/farmacocinética
10.
Ecotoxicol Environ Saf ; 193: 110355, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32120164

RESUMO

In the Montado system, in Portuguese Alentejo region, some Eutric Cambisols are known to promote manganese (Mn) toxicity in wheat. Variation on bioavailable Mn concentration depends on soil acidity, which can be increased by natural events (e.g. waterlogging) or human activity (e.g. excess use of chemical fertilizers). The effect of increasing soil Mn on crop element uptake, element distribution and oxidative stress was evaluated on winter wheat (Triticum aestivum). Plants were grown for 3 weeks in an acidic Cambisol spiked with increasing Mn concentrations (0, 45.2 and 90.4 mg MnCl2/Kg soil). Calcium (Ca), phosphorus (P), magnesium (Mg) and Mn were quantified in the soil solution, root and shoot tissues and respective subcellular fractions. The activity of the antioxidant enzymes ascorbate peroxidase (APX), catalase (CAT), glutathione reductase (GR), guaiacol peroxidase (GPX) and superoxide dismutase (SOD) were determined in extracts of wheat shoots and roots. Overall, increase in soil bioavailable Mn inhibited the uptake of other elements, increased the Ca proportion in the root apoplast, promoted the translocation of Mn and P to shoot tissues and increased their proportion in the shoot vacuoles. Wheat roots showed greater antioxidant enzymes activities than shoots. These activities decreased at the highest soil Mn concentration in both plant parts. Wheat roots appear to be more sensitive to oxidative stress derived from excess soil Mn and promote Mn translocation and storage in shoot vacuoles, probably in Mn and P complexes, as a detoxification strategy. Improvement in wheat production, in acidic soils, may rely on the enhancement of its Mn detoxification strategies.


Assuntos
Manganês/toxicidade , Poluentes do Solo/toxicidade , Triticum/efeitos dos fármacos , Antioxidantes/metabolismo , Ascorbato Peroxidases/metabolismo , Transporte Biológico , Cálcio/metabolismo , Catalase/metabolismo , Glutationa Redutase/metabolismo , Magnésio/metabolismo , Manganês/farmacocinética , Estresse Oxidativo , Peroxidase/metabolismo , Fósforo/metabolismo , Solo/química , Poluentes do Solo/farmacocinética , Superóxido Dismutase/metabolismo , Triticum/enzimologia , Triticum/metabolismo
11.
Int J Phytoremediation ; 22(4): 420-426, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32156154

RESUMO

The aim of this study is to determine the effect of GA on maize seedlings as well as its antioxidative effect under copper (Cu) stress. To that end, maize seedlings were exposed to 1.5 mM GA and 1 mM Cu solutions, and the seedlings were allocated to following experimental groups: 18-hr distilled water (DI) (Control), 6-hr GA + 12-hr DI (GA), 6-hr DI + 12-hr Cu (Cu), 6-hr GA + 12-hr Cu (GA + Cu), 12-hr Cu +6-hr GA (Cu + GA), and 18-hr GA and Cu mixture (GA = Cu). The experiment was designed by randomized block design with three repetitions. The results showed that GA alone and GA + Cu treatments significantly decreased membrane damage and H2O2 formation compared to the other treatments. GA formation was determined to be highest in turn in treatments GA + Cu and GA alone. The proline content significantly decreased in treatments GA alone and GA + Cu. The highest catalase (CAT) activity was observed in GA alone application, whereas GA + Cu treatment led to increase in guaiacol peroxidase (GPX), superoxide dismutase (SOD), and ascorbate peroxidase (APX) activities. GA has a protective effect on chlorophyll contents and relative water content (RWC), but not on carotenoid levels under Cu stress. Overall, GA alone application or GA + Cu stress may prevent the formation of reactive oxygen species (ROS) due to chelation effect of GA.


Assuntos
Plântula , Zea mays , Antioxidantes , Ascorbato Peroxidases , Biodegradação Ambiental , Catalase , Cobre , Ácido Gálico , Peróxido de Hidrogênio , Estresse Oxidativo , Superóxido Dismutase
12.
Toxicol Lett ; 326: 70-77, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32113805

RESUMO

In addition to the transfer across the placenta, placenta displays hormonal and xenobiotic metabolism, as well as enzymatic defense against oxidative stress. We analyzed aromatase (CYP19A1), uridine 5'-diphospho-glucuronyltransferase (UGT), glutathione-S-transferase (GST) and catalase (CAT) activities in over 70 placentas from nonsmokers stored at -80 °C from former perfusion studies. A wide interindividual variation in all activities was found. Longterm storage at -80 °C did not affect the activities. Ethoxyresorufin-O-deethylase (EROD, CYP1A1) was not detected in any of the studied placentas perfused with chemicals. Several compounds in placental perfusion changed statistically significantly the enzyme activities in placental tissue. Melamine and nicotine increased CYP19A1, melamine increased UGT and GST, PhIP with ethanol decreased CYP19A1 and increased GST, and PhIP with buprenorphine decreased CAT. Antipyrine in 100 µg/ml also changed the studied enzyme activities, but not statistically significantly. Because antipyrine is a reference compound in placental perfusions, its potential effects must be taken into account in human placental perfusion. Enzyme activities deserve further studies as biomarkers of placental toxicity. Finally, enzyme activities deserve further studies as biomarkers of placental toxicity.


Assuntos
Antipirina/metabolismo , Aromatase/metabolismo , Catalase/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Glucuronosiltransferase/metabolismo , Glutationa Transferase/metabolismo , Placenta/metabolismo , Adulto , Feminino , Humanos , Gravidez
13.
Bull Environ Contam Toxicol ; 104(4): 477-483, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32193572

RESUMO

The application of nano-level passivating agents in the remediation of soil heavy metal pollution has received widespread attention, but its harm to soil animals should also be addressed. This study explored the effect of three nanomaterials-nanohydroxyapatite apatite (n-HAP), nano zeolite (n-zeolite), and nanometer iron oxide (n-Fe3O4), on catalase (CAT), peroxidase (POD) and superoxide dismutase (SOD) activity and malondialdehyde (MDA) content through filter paper contact test. The effects of nanomaterials spiked at 1.5%wt of soils on earthworm avoidance behavior were also be studied, and the crystallinity and surface charge of three nanomaterials were characterized. The results showed that the activities of CAT, SOD and POD and the content of MDA have been changed at different level. And earthworms have obvious avoidance behavior to the three kinds of nanomaterials. Therefore, nanomaterials do have adverse effects on earthworms, and their biological toxicity should be considered when selecting passivating agents for soil heavy metal pollution remediation.


Assuntos
Aprendizagem da Esquiva/efeitos dos fármacos , Recuperação e Remediação Ambiental/métodos , Reação de Fuga/efeitos dos fármacos , Nanoestruturas/toxicidade , Oligoquetos/efeitos dos fármacos , Poluentes do Solo/toxicidade , Solo/química , Animais , Catalase/metabolismo , Malondialdeído/metabolismo , Nanoestruturas/química , Oligoquetos/metabolismo , Peroxidase/metabolismo , Poluentes do Solo/química , Superóxido Dismutase/metabolismo
14.
Chemosphere ; 249: 126119, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32044610

RESUMO

The addition of different functional groups to ionic liquid anions or cations to synthesize task-specific ionic liquids (TSILs) according to specific needs has become a research hotspot. However, there are few studies on the toxicity of TSILs. We selected zebrafish (Danio rerio) to assess the toxicity of three TSILs 1-aminoethyl-3-methylimidazolium tetrafluoroborate ([C2NH2MIm]BF4), 1-methoxyethyl-3-methylimidazolium tetrafluoroborate ([MOEMIm]BF4) and 1-hydroxyethyl-3-methylimidazolium tetrafluoroborate ([HOEMIm]BF4). The 96 h median lethal concentration (96 h LC50) of the three TSILs [C2NH2MIm]BF4, [MOEMIm]BF4 and [HOEMIm]BF4 on zebrafish determined by an acute toxicity test were 143.8 mg/L, 2492.5 mg/L and 3086.7 mg/L, respectively. In the oxidative damage and DNA damage research experiments, zebrafish were exposed to [C2NH2MIm]BF4 (0, 5, 10, 20 and 40 mg/L), [MOEMIm]BF4 and [HOEMIm]BF4 (0, 1, 10, 50 and 100 mg/L) for 28 days, and levels of reactive oxygen species (ROS), superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST), malondialdehyde (MDA) and olive tail moment (OTM) in zebrafish liver were tested on days 7, 14, 21 and 28 after the exposure test. During the experiment, increased contents of ROS and MDA were detected; enzymatic activities especially SOD were inhibited; and DNA damage occurred in zebrafish. The toxicity of the three TSILs was compared by the integrated biomarker response (IBR). The toxicity order of three TSILs was: [MOEMIm]BF4 > [HOEMIm]BF4 > [C2NH2MIm]BF4. In addition, this study can provide a toxicological basis for application research and the evaluation of functionalized ionic liquids with low toxicity in the future.


Assuntos
Líquidos Iônicos/toxicidade , Testes de Toxicidade Aguda , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/fisiologia , Animais , Ânions , Boratos , Catalase/metabolismo , Dano ao DNA , Glutationa Transferase/metabolismo , Fígado/metabolismo , Malondialdeído/metabolismo , Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Peixe-Zebra/metabolismo
15.
Chemosphere ; 249: 126171, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32087452

RESUMO

Carbon-based materials including multiwall carbon nanotubes (MWCNTs) have been recently implicated in a number of reports dealing with their potential use in agriculture, leading to contradictory findings. In this study, MWCNTs were successfully functionalized with carboxylic acid groups (MWCNTs-COOH) in order to increase water dispersion. Hydroponically cultured sweet basil (Ocimum basilicum L.) seedlings were subjected to four concentrations (0, 25, 50 and 100 mg L-1) of MWCNTs-COOH under three salt stress levels (0, 50 and 100 mM NaCl). An array of agronomic, physiological, analytical and biochemical parameters were evaluated in an attempt to examine the potential use of MWCNTs in plants under optimal and abiotic stress conditions. Application of MWCNTs-COOH at optimum concentration (50 mg L-1) could ameliorate the negative effects of salinity stress by increasing chlorophyll and carotenoids content and inducing non-enzymatic (i.e. phenolic content) and enzymatic antioxidant components (i.e. ascorbate peroxidase (APX), catalase (CAT) and guaiacol peroxidase (GP) activity). Furthermore, MWCNTs-COOH treatments under optimal conditions induced plant growth, while a significant increase (P ≤ 0.01) was recorded in essential oil content and compound profile. On the other hand, biochemical and epifluorescence microscopy evidence suggested that high dosage (100 mg L-1) of MWCNTs-COOH leads to toxicity effects in plant tissue. Overall, the positive response of plants to low concentrations of MWCNTs-COOH under control and abiotic stress conditions renders them as potential novel plant growth promoting and stress protecting agents, opening up new perspectives for their use in agriculture.


Assuntos
Nanotubos de Carbono/toxicidade , Ocimum basilicum/fisiologia , Antioxidantes/metabolismo , Ascorbato Peroxidases , Ácidos Carboxílicos/química , Carotenoides , Catalase , Clorofila , Nanotubos de Carbono/química , Ocimum basilicum/efeitos dos fármacos , Óleos Voláteis/metabolismo , Fenóis/metabolismo , Desenvolvimento Vegetal , Plântula/efeitos dos fármacos , Estresse Fisiológico
16.
Ecotoxicol Environ Saf ; 192: 110261, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32018153

RESUMO

The Chlorella vulgaris has been generally recognized as a promising microalgal model to study stress-related responses due to its ability to withstand against ionizing and non-ionizing radiation. The objective of the present study was to investigate the effect of CaCl2 pre-treatment at different concentrations on the responses of microalga C. vulgaris under gamma radiation toxicity. Changes in growth, physiological parameters and biochemical compositions of the algae pretreated with 0.17 (normal), 5, and 10 mM CaCl2 were analyzed under 300 Gy gamma irradiation and compared to those of gamma-free control. The results showed that parameters including specific growth rate, cell size, chlorophyll and protein contents, ascorbate peroxidase (APX), and superoxide dismutase (SOD) activity, Ferric Reducing Antioxidant Power (FRAP), and the ratios of nucleic acid to protein negatively affected by gamma irradiation. All these parameters, except for the ratios of nucleic acid to protein significantly increased in the algae when pretreated with a CaCl2 content higher than normal concentration. The analysis also showed that parameters including catalase activity, proline, and carotenoid content, the level of lipid peroxidation, and electrolyte leakage (EL) significantly increased under gamma irradiation but not affected significantly under different CaCl2 pre-treatments. Additionally, specific growth rate, chlorophyll a and protein content, APX and SOD activity, FRAP, lipid peroxidation, electrolyte leakage, and the ratios of nucleic acid to protein were the only parameters that significantly affected by the interaction of gamma toxicity and CaCl2 pretreatment. Overall, the results suggested that regardless of the CaCl2 effect, the algal cells responded to gamma radiation more efficiently by increasing proline, carotenoids content, and CAT activity. More important, it was concluded that calcium had an essential role in modifying the detrimental effect of gamma toxicity on the algae mainly by increasing the activity of ascorbate peroxidase and superoxide dismutase and maintaining the reducing antioxidant power (FRAP) of the cells at a high level.


Assuntos
Cloreto de Cálcio/farmacologia , Chlorella vulgaris/efeitos da radiação , Raios gama/efeitos adversos , Tolerância a Radiação/efeitos dos fármacos , Antioxidantes/metabolismo , Ascorbato Peroxidases/metabolismo , Carotenoides/metabolismo , Catalase/metabolismo , Chlorella vulgaris/efeitos dos fármacos , Chlorella vulgaris/crescimento & desenvolvimento , Chlorella vulgaris/metabolismo , Clorofila/metabolismo , Clorofila A/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos da radiação , Microalgas/efeitos dos fármacos , Microalgas/crescimento & desenvolvimento , Microalgas/metabolismo , Microalgas/efeitos da radiação , Prolina/metabolismo , Superóxido Dismutase/metabolismo
17.
Ecotoxicol Environ Saf ; 192: 110252, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32014725

RESUMO

Glutaredoxins (Grxs) are small multifunctional redox proteins. Grxs have glutathione-dependent oxidoreductase activity in the presence of glutathione reductase and NADPH. The role of Grxs is well studied in heavy metal tolerance in prokaryotic and mammalian systems but not in plant genera. In the present study, a chickpea glutaredoxin (CaGrx) gene (LOC101493651) has been investigated against metal stress based on its primary screening in chickpea which revealed higher up-regulation of CaGrx gene under various heavy metals (AsIII-25 µM, AsV-250 µM, Cr(VI)-300 µM, and Cd-500 µM) stress. This CaGrx gene was overexpressed in Arabidopsis thaliana and investigated various biochemical and physiological performances under each metal stress. Transgenic plants showed significant up-regulation of the CaGrx gene during qRT-PCR analysis as well as longer roots, higher seed germination, and survival efficiency during each metal stress. The levels of stress markers, TBARS, H2O2, and electrolyte leakage were found to be less in transgenic lines as compared to WT revealed less toxicity in transgenics. The total accumulation of AsIII, AsV, and Cr(VI) were significantly reduced in all transgenic lines except Cd, which was slightly reduced. The physiological parameters such as net photosynthetic rate (PN), stomatal conductance (gs), transpiration (E), water use efficiency (WUE), photochemical quenching (qP), and electron transport rate (ETR), were maintained in transgenic lines during metal stress. Various antioxidant enzymes such as glutaredoxin (GRX), glutathione reductase (GR), glutathione peroxidase (GPX), glutathione-S-transferase (GST), ascorbate peroxidase (APX), superoxide dismutase (SOD), catalase (CAT), dehydroascorbate reductase (DHAR), monodehydroascorbate reductase (MDHAR), antioxidant molecules (ascorbate, GSH) and stress-responsive amino acids (proline and cysteine) levels were significantly increased in transgenic lines which provide metal tolerance. The outcome of this study strongly indicates that the CaGrx gene participates in the moderation of metal stress in Arabidopsis, which can be utilized in biotechnological interventions to overcome heavy metal stress conditions in different crops.


Assuntos
Antioxidantes/metabolismo , Cicer/enzimologia , Glutarredoxinas/metabolismo , Metais Pesados/toxicidade , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/fisiologia , Ascorbato Peroxidases/metabolismo , Catalase/metabolismo , Glutarredoxinas/genética , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Estresse Oxidativo , Oxirredutases/metabolismo , Superóxido Dismutase/metabolismo
18.
Ecotoxicol Environ Saf ; 192: 110248, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32036096

RESUMO

Neonicotinoids emerged as an environmentally safe alternative to previous generations of insecticides becoming one of the most widely applied in modern agriculture. Nevertheless, they have been reported to affect several non-target organisms. Most toxicity studies focus on the effects on pollinators or terrestrial invertebrates and evaluate either the active ingredient or the commercial formulation. In the present study, we aimed to assess the long-term effects of the active ingredient acetamiprid and a broadly used commercial formulation (Assail® 70) on the non-target freshwater gastropod Biomphalaria straminea using a battery of biomarkers. A 14 day-exposure of adult organisms to both active ingredient and commercial formulation increased carboxylesterase activity and glutathione content, inhibited superoxide dismutase activity and decreased reactive oxygen species levels. The commercial formulation additionally increased glutathione S-transferase activity and inhibited catalase activity. The results indicate a greater toxicity of the commercial formulation than that of the active ingredient alone. Cholinesterase activity, development and offspring survival of B. straminea were not impaired. We conclude that the toxicity of acetamiprid on this gastropod species is mainly related to effects on detoxification and oxidative metabolism responses. This study provides novel information about the adverse effects of the active ingredient and a commercial formulation of a widely used neonicotinoid on a non-target aquatic species.


Assuntos
Biomphalaria/efeitos dos fármacos , Inseticidas/toxicidade , Neonicotinoides/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/metabolismo , Biomarcadores/metabolismo , Biomphalaria/enzimologia , Biomphalaria/metabolismo , Carboxilesterase/metabolismo , Catalase/metabolismo , Água Doce , Glutationa/metabolismo , Glutationa Transferase/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
19.
Sci Total Environ ; 718: 137234, 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32087580

RESUMO

Increasing atmospheric carbon dioxide has led to a decrease in the pH of the ocean, which influences the speciation of heavy metals and consequently affects metal toxicity in marine organisms. To investigate the effects of seawater acidification and metals on the antioxidant defenses of marine fishes, the flounder Paralichthys olivaceus, was continuously exposed to cadmium (Cd; control, 0.01 and 0.15 mg L-1) and acidified seawater (control (pH 8.10), 7.70 and 7.30) for 49 days from embryogenesis to settlement. The results demonstrated that both Cd and acidified seawater could induce oxidative stress and consequently cause lipid peroxidation (LPO) in the larvae. Antioxidants (i.e., superoxide dismutase, SOD; catalase, CAT; reduced glutathione, GSH; glutathione S-transferase, GST; glutathione peroxidase, GPx; and glutathione reductase, GR) functioned to defend the larvae against oxidative damage. Overall, Cd induced (SOD, GST and GSH) or inhibited (CAT and GPx) the enzymatic activities or contents of all the selected antioxidants except for GR. The antioxidants responded differently to seawater acidification, depending on their interaction with the metal. Similarly, the mRNA expressions of the antioxidant-related genes were upregulated (sod, gr and gst) or downregulated (cat and gpx) in response to increasing Cd exposure. Seawater acidification did not necessarily affect all of the biomarkers; in some cases (e.g., SOD and sod, GR and gr), Cd stress may have exceeded and masked the stress from seawater acidification in regulating the antioxidant defense of the larvae. The integrated biomarker response (IBR) was enhanced with increasing levels of the stressors. These findings support the hypothesis that seawater acidification not only directly affects the antioxidant defense in flounder larvae but also interacts with Cd to further regulate this defense. This study has ecological significance for assessing the long-term impacts of ocean acidification and metal pollution on the recruitment of fish populations in the wild.


Assuntos
Linguado , Animais , Antioxidantes , Cádmio , Catalase , Glutationa , Concentração de Íons de Hidrogênio , Larva , Peroxidação de Lipídeos , Estresse Oxidativo , Água do Mar , Superóxido Dismutase
20.
Ecotoxicol Environ Saf ; 192: 110315, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32058162

RESUMO

Tea (Camellia sinensis), widely planted in the south of China, and often exposed to acid rain. However, research concerning the impacts of acid rain on physiology and biochemistry of tea plants is still scarce. In this study, we investigated the influence of simulated acid rain (SAR) on plant height, root length, photosynthetic pigment, Fv/Fm, proline, malondialdehyde, antioxidant enzyme activity, total nitrogen, caffeine, catechins, and free amino acids. Our results showed that SAR at pH 4.5 did not hinder plant development because growth characteristics, photosynthesis, and ascorbate peroxidase and catalase activities did not decrease at this pH compared to those at the other investigated pH values. However, at pH 3.5 and pH 2.5, the activities of antioxidase and concentrations of malondialdehyde and proline increased significantly in response to the decrease of photosynthetic pigments and Fv/Fm. In addition, the increase in acidity increased total nitrogen, certain amino acid content (theanine, cysteine), and decreased catechin and caffeine contents, resulting in an imbalance of the carbon and nitrogen metabolisms. Our results indicated that SAR at pH 3.5 and pH 2.5 could restrict photosynthesis and the antioxidant defense system, causing metabolic disorders and ultimately affecting plant development and growth, but SAR at pH 4.5 had no toxic effects on tea seedlings when no other stress factors are involved.


Assuntos
Chuva Ácida/toxicidade , Camellia sinensis/efeitos dos fármacos , Aminoácidos/metabolismo , Antioxidantes/metabolismo , Ascorbato Peroxidases/metabolismo , Cafeína/análise , Camellia sinensis/química , Camellia sinensis/crescimento & desenvolvimento , Camellia sinensis/metabolismo , Catalase/metabolismo , Catequina/metabolismo , Malondialdeído/metabolismo , Nitrogênio/análise , Estresse Oxidativo , Fotossíntese/efeitos dos fármacos , Folhas de Planta/metabolismo , Plântula/química , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/metabolismo
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