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1.
Ecotoxicol Environ Saf ; 203: 110980, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32888623

RESUMO

Pesticides can enter aquatic environments potentially affecting non-target organisms. Unfortunately, the effects of such substances are still poorly understood. This study investigated the effects of the active neonicotinoid substance thiacloprid (TH) and the commercial product Calypso 480 SC (CA) (active compound 40.4% TH) on Mytilus galloprovincialis after short-term exposure to sublethal concentrations. Mussels were tested for seven days to 0, 1, 5 and 10 mg L-1 TH and 0, 10, 50 and 100 mg L-1 CA. For this purpose, several parameters, such as cell viability of haemocytes and digestive cells, biochemical haemolymph features, superoxide dismutase (SOD) and catalase (CAT) enzymatic activity of gills and digestive gland, as well as histology of such tissues were analysed. The sublethal concentrations of both substances lead to abatement or completely stopping the byssal fibres creation. Biochemical analysis of haemolymph showed significant changes (P < 0.01) in electrolytes ions (Cl-, K+, Na+, Ca2+, S-phosphor), lactate dehydrogenase (LDH) enzyme activity and glucose concentration following exposure to both substances. The TH-exposed mussels showed significant imbalance (P < 0.05) in CAT activity in digestive gland and gills. CA caused significant decrease (P < 0.05) in SOD activity in gills and in CAT activity in both tissues. Results of histological analyses showed severe damage in both digestive gland and gills in a time- and concentration-dependent manner. This study provides useful information about the acute toxicity of a neonicotinoid compound and a commercial insecticide on mussels. Nevertheless, considering that neonicotinoids are still widely used and that mussels are very important species for marine environment and human consumption, further researches are needed to better comprehend the potential risk posed by such compounds to aquatic non-target species.


Assuntos
Brânquias/efeitos dos fármacos , Hemolinfa/efeitos dos fármacos , Inseticidas/toxicidade , Mytilus/efeitos dos fármacos , Neonicotinoides/toxicidade , Tiazinas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Catalase/metabolismo , Sobrevivência Celular , Relação Dose-Resposta a Droga , Brânquias/enzimologia , Hemócitos/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Testes de Toxicidade Aguda
2.
Ecotoxicol Environ Saf ; 202: 110916, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32800251

RESUMO

Selenium (Se) at low concentration is considered benefit element to plants. The range between optimal and toxic concentration of Se is narrow and varies among plant species. This study aimed to evaluate the phenotypic, physiological and biochemical responses of four rice genotypes (BRS Esmeralda, BRSMG Relâmpago, BRS Bonança and Bico Ganga) grown hydroponically treated with sodium selenate (1.5 mM L-1). Selenium treated plants showed a dramatically decrease of soluble proteins, chlorophylls, and carotenoids concentration, resulting in the visual symptoms of toxicity characterized as leaf chlorosis and necrosis. Selenium toxicity caused a decrease on shoot and root dry weight of rice plants. Excess Se increased the oxidative stress monitored by the levels of hydrogen peroxide and lipid peroxidation. The enzymatic antioxidant system (catalase, superoxide dismutase, and ascorbate peroxidase) increased in response to Se supply. Interestingly, primary metabolism compounds such as sucrose, total sugars, nitrate, ammonia and amino acids increased in Se-treated plants. The increase in these metabolites may indicate a defense mechanism for the osmotic readjustment of rice plants to mitigate the toxicity caused by Se. However, these metabolites were not effective to minimize the damages on phenotypic traits such as leaf chlorosis and reduced shoot and root dry weight in response to excess Se. Increased sugars profile combined with antioxidant enzymes activities can be an effective biomarkers to indicate stress induced by Se in rice plants. This study shows the physiological attributes that must be taken into account for success in the sustainable cultivation of rice in environments containing excess Se.


Assuntos
Oryza/fisiologia , Selênio/toxicidade , Poluentes do Solo/toxicidade , Antioxidantes/metabolismo , Ascorbato Peroxidases/metabolismo , Catalase/metabolismo , Clorofila/metabolismo , Peróxido de Hidrogênio/metabolismo , Hidroponia , Peroxidação de Lipídeos , Oryza/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Folhas de Planta/metabolismo , Ácido Selênico/metabolismo , Superóxido Dismutase/metabolismo
3.
Int J Nanomedicine ; 15: 4763-4778, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32753865

RESUMO

Introduction: Methotrexate exhibits poor cutaneous bioavailability and systemic side effects on topical administration, so there is an unmet need for a novel carrier and its optimized therapy. Methotrexate-loaded nanostructured lipid carriers (MTXNLCs) were formulated and characterized to determine in vitro drug release and evaluate the role of MTXNLC gel in the topical treatment of psoriasis. Methods: A solvent diffusion technique was employed to prepare MTXNLCs, which was optimized using 32 full factorial designs. The mean diameter and surface morphology of MTXNLCs was evaluated. The crystallinity of lyophilized MTXNLCs was characterized by differential scanning calorimetry (DSC) and powder X-ray diffraction (XRD). MTXNLCs were integrated in 1% w/w Carbopol 934 P gel base, and in vitro skin deposition studies in human cadaver skin (HCS) were carried out. Results: The optimized MTXNLCs were rod-shaped, with an average particle size of 253 ± 8.65 nm, a zeta potential of -26.4±0.86 mV, and EE of 54.00±1.49%. DSC and XRD data confirmed the formation of NLCs. Significantly higher deposition of MTX was found in HCS from MTXNLC gel (71.52 ±1.13%) as compared to MTX plain gel (38.48±0.96%). In vivo studies demonstrated significant improvement in therapeutic response and reduction in local side effects with MTXNLCs-loaded gel in the topical treatment of psoriasis. Anti-psoriatic efficacy of MTXNLCs 100 ug/cm2 compared with plain MTX gel was evaluated using imiquimod (IMQ)-induced psoriasis in BALB/c mice. The topical application of MTXNLCs to the mouse ear resulted in a significant reduction of psoriatic area and severity index, oxidative stress, inflammatory cytokines like TNF-α, IL-1ß, and IL-6 and IMQ-induced histopathological alterations in mouse ear samples. Conclusion: Developed formulation of MTXNLC gel demonstrated better anti-psoriatic activity and also displayed prolonged and sustained release effect, which shows that it can be a promising alternative to existing MTX formulation for the treatment of psoriasis.


Assuntos
Composição de Medicamentos , Géis/química , Imiquimode/uso terapêutico , Inflamação/tratamento farmacológico , Lipídeos/química , Metotrexato/uso terapêutico , Nanoestruturas/química , Psoríase/tratamento farmacológico , Administração Cutânea , Administração Tópica , Animais , Catalase/metabolismo , Citocinas/metabolismo , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Glutationa/metabolismo , Humanos , Inflamação/patologia , Malondialdeído/metabolismo , Camundongos Endogâmicos BALB C , Nanoestruturas/ultraestrutura , Tamanho do Órgão , Superóxido Dismutase/metabolismo
4.
Int J Nanomedicine ; 15: 5005-5016, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764932

RESUMO

Background and Aim: With the wide applications of chitosan and gold nanoparticles in drug delivery and many consumer products, there is limited available information about their effects on drug-metabolizing enzymes (DMEs). Changes in DMEs could result in serious drug interactions. Therefore, this study aimed to investigate the effects of exposure to chitosan or gold nanoparticles on hepatic Phase I and II DMEs, liver function and integrity, oxidative damage and liver architecture in male rats. Methods: Animals were divided into three equal groups: a control group, a group treated with chitosan nanoparticles (200 mg/kg, 50±5 nm) and a group treated with gold nanoparticles (4 mg/kg, 15±5 nm). Rats were orally administered their respective doses daily for 10 days. Results: Both chitosan and gold nanoparticles decreased the body weights by more than 10%. Gold nanoparticles reduced the activities of antioxidants (superoxide dismutase and catalase), and reduced glutathione level and elevated the malondialdehyde level in the liver. Gold nanoparticles caused significant reductions in CYP1A1, CYP2E1, quinone oxidoreductase1, and glutathione S-transferase and elevated CYP2D6 and N-acetyl transferase2. Chitosan elevated CYP2E1 and CYP2D6 and reduced UDP-glucuronosyltransferase 1A1. Both nanoparticles disturbed the architecture of the liver, but the deleterious effects after gold nanoparticles treatment were more prominent. Conclusion: Taken together, gold nanoparticles severely perturbed the DMEs and would result in serious interactions with many drugs, herbs, and foods.


Assuntos
Antioxidantes/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Inativação Metabólica/efeitos dos fármacos , Fígado/efeitos dos fármacos , Nanopartículas Metálicas/efeitos adversos , Animais , Catalase/genética , Catalase/metabolismo , Quitosana/química , Citocromo P-450 CYP1A1/metabolismo , Citocromo P-450 CYP2E1/genética , Citocromo P-450 CYP2E1/metabolismo , Interações Medicamentosas , Glucuronosiltransferase/genética , Glucuronosiltransferase/metabolismo , Glutationa/metabolismo , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Ouro/química , Ouro/farmacocinética , Fígado/metabolismo , Fígado/patologia , Masculino , Malondialdeído/metabolismo , Nanopartículas Metálicas/química , Ratos Wistar , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo
5.
Ecotoxicol Environ Saf ; 202: 110954, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32800228

RESUMO

Current study aims to determine difference in metal accumulation pattern in muscle of Liza parsia (pelagic, omnivore), Amblypharyngodon mola (surface feeder, herbivore) and Mystus gulio (benthic, carnivore) depending on their niche and feeding habit and how it affects the endogenous antioxidants and glucose metabolism in fish muscle. Fishes were collected from Malancha, Diamond Harbour and Chandanpiri, West Bengal, India. Concentrations of lead, zinc, cadmium, chromium were measured in water, sediment and fish muscle. Metal pollution index (MPI) and bioconcentration factor (BCF) was calculated to evaluate the ability of fish to accumulate specific metals in muscle tissue from the aquatic environment. Metal concentrations were found significantly higher (P < 0.05) in water, sediment, fish muscles from Malancha than Chandanpiri and Diamond Harbour. L. parsia (MPI: 0.4-1.6) showed highest metal deposition in their muscle followed by A. mola (MPI: 0.37-1.38) and M. gulio (MPI: 0.2-1.2). Malondealdehyde, superoxide dismutase, catalase, glutathione S transferase, glutathione reductase and cortisol levels increased in case of L. parsia from Malancha and Chandanpiri. Succinate dehydrogenase, lactate dehydrogenase, Ca+2 ATPase and cytochrome C oxidase levels were significantly (P < 0.05) lower at Malancha and Chandanpiri than Diamond Harbour. Heat shock protein (HSP70) expression was significantly (P < 0.05) higher in all fish species at Malancha followed by Chandanpiri and Diamond Harbour. Glucose, glycogen, hexokinase, phosphofructokinase and glycogen phosphorylase levels varied between sites and selected fish species. Serum cortisol level was measured and found to be the highest in L. parsia from Malancha (2.94 ± 0.12 ng/ml) and the lowest in M. gulio from Diamond Harbour (0.7 ± 0.05 ng/ml). The results indicate that metal toxicity alters antioxidant levels, oxidative status and energy production in fish in species specific manner. Our results also indicate that Mystus has the highest degree of adaptability in response to metal toxicity possibly due to its specific food habit and niche position. Therefore, it can be concluded that maintenance of oxidative and metabolic status to combat metal-induced oxidative load will be helpful for the fishes to acquire better resistance under such eco-physiological stress. Alteration of niche and interactive segregation in aquatic organism may be one of the key modulator of resistance against such stress.


Assuntos
Antioxidantes/metabolismo , Cyprinidae/metabolismo , Comportamento Alimentar/fisiologia , Glucose/metabolismo , Metais Pesados/toxicidade , Músculos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Catalase/metabolismo , Cyprinidae/fisiologia , Glutationa Redutase/metabolismo , Glutationa Transferase/metabolismo , Índia , Metais Pesados/metabolismo , Músculos/enzimologia , Músculos/metabolismo , Oxirredução , Especificidade da Espécie , Superóxido Dismutase/metabolismo , Poluentes Químicos da Água/metabolismo
6.
Ecotoxicol Environ Saf ; 204: 111069, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32758696

RESUMO

We studied the absorption, cytotoxicity and oxidative stress markers of Paralytic Shellfish Toxins (PST) from three extracts from Alexandrium catenella and A. ostenfeldii, in middle Oncorhynchus mykiss intestine in vitro and ex vivo preparations. We measured glutathione (GSH) content, glutathione-S transferase (GST), glutathione reductase (GR) and catalase (CAT) enzymatic activity, and lipid peroxidation in isolated epithelium exposed to 0.13 and 1.3 µM PST. ROS production and lysosomal membrane stability (as neutral red retention time 50%, NRRT50) were analyzed in isolated enterocytes exposed to PST alone or plus 3 µM of the ABCC transport inhibitor MK571. In addition, the concentration-dependent effects of PST on NRRT50 were assayed in a concentration range from 0 to 1.3 µM PST. We studied the effects of three different PST extracts on the transport rate of the ABCC substrate DNP-SG by isolated epithelium. The extract with highest inhibition capacity was selected for studying polarized DNP-SG transport in everted and non-everted intestinal segments. We registered lower GSH content and GST activity, and higher GR activity, with no significant changes in CAT activity, lipid peroxidation or ROS level. PST exposure decreased NRRT50 in a concentration-depend manner (IC50 = 0.0045 µM), but PST effects were not augmented by addition of MK571. All the three PST extracts inhibited ABCC transport activity, but this inhibition was effective only when the toxins were applied to the apical side of the intestine and DNP-SG transport was measured at the basolateral side. Our results indicate that PST are absorbed by the enterocytes from the intestine lumen. Inside the enterocytes, these toxins decrease GSH content and inhibit the basolateral ABCC transporters affecting the normal functions of the cell. Furthermore, PST produce a strong cytotoxic effect to the enterocytes by damaging the lysosomal membrane, even at low, non-neurotoxic concentrations.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Glutationa/análogos & derivados , Mucosa Intestinal/efeitos dos fármacos , Lisossomos/efeitos dos fármacos , Oncorhynchus mykiss/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Saxitoxina/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Catalase/metabolismo , Dinoflagelados/metabolismo , Enterócitos/efeitos dos fármacos , Enterócitos/metabolismo , Glutationa/metabolismo , Glutationa Transferase/metabolismo , Mucosa Intestinal/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Lisossomos/metabolismo , Frutos do Mar
7.
Aquat Toxicol ; 225: 105552, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32615475

RESUMO

There is scarce investigation addressing interpopulation tolerance responses to address the influence of a history of chronic stress exposure, as that occurring in polluted environments, in photoautotrophs. We evaluated ecophysiological (photosynthetic activity) and metabolic (oxidative stress and damage) responses of two populations of green macroalga Ulva compressa from polluted (Ventanas) and non-polluted (Cachagua) localions of central Chile, and exposed to controlled hypersalinity conditions of 32 (control), 42, 62 and 82 psu (practical salinity units) for 6 h, 48 h and 6 d. Both primary production (ETRmax) and photosynthetic efficiency (αETR) were generally higher in the population from Cachagua compared to Ventanas at all times and salinities. Moreover, at most experimental times and salinities the population from Ventanas had greater levels of H2O2 and lipid peroxidation that individuals from Cachagua. Total ascorbate was higher in the population of Cachagua than Ventanas at 42 and 82 psu after 6 and 48 h, respectively, while at 6 d concentrations were similar between both populations at all salinities. Total glutathione was greater in both populations after 6 h at all salinities, but at 48 h its concentrations were higher only in the population from Cachagua, a trend that was maintained at 6 d under 82 psu only. Reduced and oxidized ascorbate (ASC and DHA, respectively) and glutathione (GSH and GSSG, respectively) demonstrated similar patterns between U. compressa populations, with an increase oxidation with greater salinities but efficient recycling to maintain sufficient batch of ASC and GSH. When assessing the expression of antioxidant enzymes catalase (CAT), superoxide dismutase (SOD) and dehydroascorbate reductase (DHAR), while the population of Ventanas displayed a general trend of upregulation with increasing salinities along the experiments, U. compressa from Cachagua revealed patterns of downregulation. Results demonstrated that although both populations were still viable after the applied hypersalinities during all experimental times, biological performance was usually more affected in the population from the Ventanas than Cachagua, likely due to a depressed baseline metabolism after a long history of exposition to environmental pollution.


Assuntos
Ulva/fisiologia , Poluentes Químicos da Água/toxicidade , Antioxidantes/metabolismo , Ácido Ascórbico/metabolismo , Catalase/metabolismo , Chile , Poluição Ambiental , Glutationa/metabolismo , Peróxido de Hidrogênio/metabolismo , Peroxidação de Lipídeos , Oxirredução , Estresse Oxidativo , Salinidade , Alga Marinha/metabolismo , Superóxido Dismutase/metabolismo , Ulva/enzimologia
8.
Chemosphere ; 255: 127041, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32679635

RESUMO

Microplastics pollution in farmlands has become a major concern. However, few studies have assessed the effects of microplastics on higher plants. In this study, we investigated the influence of polystyrene nanoplastics (PSNPs, 50 mg L-1), with four different particle sizes (100, 300, 500, and 700 nm), on the physiological and biochemical indexes of cucumber leaves. The biomass of cucumber plants significantly decreased after exposure to 300 nm PSNPs. Similarly, the chlorophyll a, chlorophyll b, soluble sugar, carotenoid, and proline content, as well as the fluorescence of cucumber leaves were significantly reduced by 100 nm PSNPs. Malondialdehyde, proline, peroxidase gene expression and enzyme activity, and hydrogen peroxide content significantly increased in cucumber leaves exposed to 700 nm PSNPs. In addition, increasing PSNPs particle size led to decreased relative expression levels and activities of the major antioxidant enzymes superoxide dismutase and catalase, while vitamin C and soluble protein content significantly increased. Overall, our results indicated that PSNPs affect the photosynthetic, antioxidant, and sugar metabolism systems of cucumber leaves, with the latter clearly affecting the total biomass of cucumber plants. The benzene ring resulting from the degradation of PSNPs in cucumber leaves may be the main factor affecting chlorophyll metabolism and sugar metabolism. Our findings provide a scientific basis for the risk assessment of PSNPs exposure in soil-plant systems.


Assuntos
Cucumis sativus/fisiologia , Poliestirenos/toxicidade , Poluentes do Solo/toxicidade , Antioxidantes/metabolismo , Carotenoides/metabolismo , Catalase/metabolismo , Clorofila , Clorofila A , Cucumis sativus/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , Malondialdeído/metabolismo , Peroxidases/metabolismo , Fotossíntese/efeitos dos fármacos , Folhas de Planta/metabolismo , Plásticos/metabolismo , Poliestirenos/metabolismo , Superóxido Dismutase/metabolismo
9.
Bull Environ Contam Toxicol ; 105(2): 255-260, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32632463

RESUMO

The present study investigated the biochemical toxicity and potential detoxification mechanisms in earthworms Eisenia fetida exposed to sulfamethazine (SMZ) (7.5, 15 and 30 mg kg-1) either alone or in combination with Copper (Cu) (100 mg kg-1) in soil. The results showed that increasing concentrations of SMZ in soil activated superoxide dismutase, catalase and glutathione peroxidase isozymes, suggesting reactive oxygen species (ROS) burst in earthworms. Treatment with SMZ and Cu separately or in combination caused protein oxidation and damage, elevating the synthesis of ubiquitin, the 20S proteasome, cytochrome P450 (CYP450), and heat shock protein 70 (HSP70). Such treatments also induced the activities of proteases, endoproteinase (EP) and glutathione S-transferases (GSTs). The results suggested that the ubiquitin-20S proteasome, proteases, EP and HSP70 were involved in degradation or remediation of oxidatively damaged proteins. Elevated levels of CYP450 and GSTs also participated in the detoxification of the earthworms.


Assuntos
Cobre/toxicidade , Oligoquetos/efeitos dos fármacos , Poluentes do Solo/toxicidade , Solo/química , Sulfametazina/toxicidade , Animais , Biodegradação Ambiental , Catalase/metabolismo , China , Cobre/metabolismo , Glutationa Peroxidase/metabolismo , Oligoquetos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Poluentes do Solo/metabolismo , Sulfametazina/metabolismo , Superóxido Dismutase/metabolismo
10.
Chem Biol Interact ; 328: 109197, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32710900

RESUMO

The present study was undertaken to assess the effect of imatinib mesylate; a tyrosine kinase inhibitor and a well-known anticancer with numerous medical benefits on blood sugar levels, insulin, and glucagon secretion in an experimental model of STZ-induced diabetes mellitus. Type 1 diabetes mellitus (T1DM) was induced by a single I.P. injection of Streptozotocin (STZ) (50 mg/kg) in male Sprague-Dawley rats. Daily oral imatinib (10 mg/kg) and (20 mg/kg) for 4 weeks induced a significant attenuation in signs of DM in rats reflected in their assessed lab values. Biomarkers of cell injury, tissue necrosis, and apoptosis; caspase-3 were significantly reduced with imatinib treatment. Furthermore, pancreatic antioxidants defenses of which; superoxide dismutase (SOD) and catalase activities, reduced glutathione (GSH) concentration, and total antioxidant capacity have significantly improved with a simultaneous reduction in malondialdehyde (MDA) content. Histopathologically, imatinib treatment was associated with a minimal pancreatic injury and marked restoration of insulin content in ß-cells. Moreover, imatinib treatment revealed a significant reduction in the infiltration of macrophages in ß-cells. Imatinib's ameliorative impact on DM may be attributed to it's mediated protection and preservation of pancreatic ß-cells function and the improvement in serum insulin levels and hence the improvement of blood glucose and overall glycemic control.


Assuntos
Diabetes Mellitus Experimental/patologia , Mesilato de Imatinib/farmacologia , Células Secretoras de Insulina/metabolismo , Administração Oral , Animais , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Antioxidantes/metabolismo , Biomarcadores/sangue , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Caspase 3/metabolismo , Catalase/metabolismo , Diabetes Mellitus Experimental/sangue , Modelos Animais de Doenças , Glucagon/sangue , Glutationa/metabolismo , Insulina/sangue , Células Secretoras de Insulina/efeitos dos fármacos , Masculino , Malondialdeído/metabolismo , Tamanho do Órgão/efeitos dos fármacos , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Ratos Sprague-Dawley , Estreptozocina , Superóxido Dismutase/metabolismo
11.
PLoS One ; 15(7): e0236389, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32730276

RESUMO

Streptococcus pneumoniae (Pneumococcus) infections affect millions of people worldwide, cause serious mortality and represent a major economic burden. Despite recent successes due to pneumococcal vaccination and antibiotic use, Pneumococcus remains a significant medical problem. Airway epithelial cells, the primary responders to pneumococcal infection, orchestrate an extracellular antimicrobial system consisting of lactoperoxidase (LPO), thiocyanate anion and hydrogen peroxide (H2O2). LPO oxidizes thiocyanate using H2O2 into the final product hypothiocyanite that has antimicrobial effects against a wide range of microorganisms. However, hypothiocyanite's effect on Pneumococcus has never been studied. Our aim was to determine whether hypothiocyanite can kill S. pneumoniae. Bactericidal activity was measured in a cell-free in vitro system by determining the number of surviving pneumococci via colony forming units on agar plates, while bacteriostatic activity was assessed by measuring optical density of bacteria in liquid cultures. Our results indicate that hypothiocyanite generated by LPO exerted robust killing of both encapsulated and nonencapsulated pneumococcal strains. Killing of S. pneumoniae by a commercially available hypothiocyanite-generating product was even more pronounced than that achieved with laboratory reagents. Catalase, an H2O2 scavenger, inhibited killing of pneumococcal by hypothiocyanite under all circumstances. Furthermore, the presence of the bacterial capsule or lytA-dependent autolysis had no effect on hypothiocyanite-mediated killing of pneumococci. On the contrary, a pneumococcal mutant deficient in pyruvate oxidase (main bacterial H2O2 source) had enhanced susceptibility to hypothiocyanite compared to its wild-type strain. Overall, results shown here indicate that numerous pneumococcal strains are susceptible to LPO-generated hypothiocyanite.


Assuntos
Lactoperoxidase/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Streptococcus pneumoniae/enzimologia , Tiocianatos/farmacologia , Anti-Infecciosos/farmacologia , Autólise , Cápsulas Bacterianas/efeitos dos fármacos , Catalase/metabolismo , Peróxido de Hidrogênio/farmacologia , Oxirredução , Piruvato Oxidase/deficiência , Piruvato Oxidase/metabolismo , Streptococcus pneumoniae/efeitos dos fármacos , Streptococcus pneumoniae/crescimento & desenvolvimento
12.
Aquat Toxicol ; 226: 105559, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32652412

RESUMO

High nitrate (NO3--N) concentration is a growing aquatic risk concern worldwide. However, adverse effects of high NO3--N concentration on submerged macrophytes-epiphytic biofilms are unclear. In this study, the alterations in physiological changes, biofilms formation and chemical compositions were investigated on leaves of Vallisneria asiatica exposed to different NO3--N concentrations. The findings showed that 10 mg L-1NO3--N resulted in low photosynthetic efficiency by inhibiting chlorophyll content 26.2 % and decreased intrinsic efficiency of photosystem II significantly at 14th day post treatment. Malondialdehyde, several antioxidant enzyme activities (i.e., superoxide dismutase, peroxidase and catalase), and secondary metabolites (i.e., phenolic compounds and anthocyanin) were all significantly up-regulated with 10 mg L-1NO3--N, implied oxidative stress were stimulated. However, no significant alterations in these indicators were observed with 5 mg L-1NO3--N. Compared to control, 10 mg L-1NO3--N concentration significantly stimulated microbes growth in biofilm and reduced the roughness of leaf-biofilms surface, but it had little effect on the biofilms distribution (from single clone to blocks) as revealed by scanning electron microscope and multifractal analysis. Results from X-ray photoelectron spectroscopy analysis showed that the percentage of P, Cl, K and the ratio of O1 (-O-) /O2 (C = O) were higher in leaves of control than treatments with 10 mg L-1NO3--N, indicating that 10 mg L-1NO3--N concentration exhibited significant inhibition of chemical activity and nutrient uptake of the leaf surfaces. Overall, these results demonstrated that high NO3--N does stimulate the biofilm growth and can cause negative impacts on submerged macrophytes growth.


Assuntos
Biofilmes/crescimento & desenvolvimento , Hydrocharitaceae/efeitos dos fármacos , Nitratos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Biofilmes/efeitos dos fármacos , Catalase/metabolismo , Clorofila/metabolismo , Hydrocharitaceae/crescimento & desenvolvimento , Hydrocharitaceae/metabolismo , Hydrocharitaceae/microbiologia , Malondialdeído/metabolismo , Peroxidases/metabolismo , Fotossíntese/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Folhas de Planta/microbiologia , Superóxido Dismutase/metabolismo
13.
Aquat Toxicol ; 226: 105554, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32653664

RESUMO

The NF-E2-related factor 2 (Nrf2), an ubiquitous, evolutionarily conserved transcription factor, acts as a major sensor of oxidative stress in cells. In the present study, a Nrf2 homolog was newly identified in the thick shell mussel Mytilus coruscus. Accordingly, its functional role in antioxidant defense in response to acute benzo(a)pyrene (Bap) exposure was assessed. The newly identified McNrf2 affiliated to traditional Nrf2 family through Blast, multiple alignment and phylogenetic analysis. After acute exposure to Bap, antioxidants including superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathine reductase (GR) were significantly induced in gills and digestive glands at both mRNA and enzymatic levels, and the expression of McNrf2 mRNA was also up-regulated. The analysis of correlating the expression of McNrf2 and the mRNA levels of these antioxidant genes showed positive ties, indicating that Nrf2 was needed for protracted induction of such genes. Further, the recombinant McNrf2 was produced through pET-32a prokaryotic system. After 50 µg/L Bap exposure, ROS generation and LPO level in gills of Nrf2 over-expressed mussels significantly decreased compared to Nrf2 wild-type mussels, as well as reduced ROS production in digestive glands. Collectively, these results show that Nrf2 pathway can provide protection from oxidative stress triggered by Bap in the thick shell mussel.


Assuntos
Antioxidantes/metabolismo , Benzo(a)pireno/toxicidade , Mytilus/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Catalase/metabolismo , Sistema Digestório/efeitos dos fármacos , Sistema Digestório/metabolismo , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Glutationa Peroxidase/metabolismo , Mytilus/metabolismo , Fator 2 Relacionado a NF-E2/genética , Estresse Oxidativo/genética , Filogenia , Superóxido Dismutase/metabolismo
14.
Life Sci ; 257: 118132, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32710949

RESUMO

AIM: Arsenic, an environmental contaminant, represents a public health problem worldwide. Studies have shown its association with molecular mechanisms related to cardiomyocytes redox balance. However, the microstructure and ultrastructure of cardiac tissue, as well as the activity of its antioxidant defenses front of disturbances in the mineral bioavailability induced by arsenic are still scarce. Thus, the aim of this study was to evaluate if arsenic exposure might induce structural and ultrastructural damages in cardiac tissue, including pathological remodeling of the parenchyma and stroma. Moreover, its impact on micromineral distribution and antioxidant enzymes activity in heart tissue was also evaluated. MAIN METHODS: Adult male Wistar rats were divided into three groups that received 0, 1 and 10 mg/L sodium arsenite in drinking water for eight weeks. The hearts were collected and subjected to structural and ultrastructural analysis, mineral microanalysis and antioxidant enzymes quantification. Functional markers of cardiac damages were evaluated using serum samples. KEY FINDINGS: Arsenic exposure induced dose-dependent structural and ultrastructural remodeling of cardiac tissue, with parenchyma loss, increase of stroma components, collagen deposition, and pathological damages such as inflammation, sarcomere disorganization, mitochondria degeneration and myofilament dissociation. Moreover, this metalloid was bioaccumulated in the tissue affecting its micromineral content, which resulted in antioxidant imbalance and increased levels of oxidative stress and cardiac markers. SIGNIFICANCE: Taken together, our findings indicate that the heart is a potential target to arsenic toxicity, and long-term exposure to this metalloid must be avoided, once it might induce several cardiac tissue pathologies.


Assuntos
Arsênico/toxicidade , Coração/efeitos dos fármacos , Miocárdio/patologia , Remodelação Ventricular/efeitos dos fármacos , Animais , Arsênico/administração & dosagem , Arsênico/análise , Catalase/metabolismo , Relação Dose-Resposta a Droga , Glutationa Transferase/metabolismo , Masculino , Miocárdio/química , Miocárdio/ultraestrutura , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo
15.
Food Chem ; 333: 127433, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32659662

RESUMO

This study examined the effects of exogenous citrulline (control, 1 and 2 mM) and water availability (100%, 50% and 25% WA) on antioxidant attributes and essential oil constituents of Hyssopus officinalis L. in two successive harvests. Hyssop tolerantly responded to water deficiency by well-promoted antioxidant enzymes (i.e., superoxide dismutase, and catalase), strong DPPH-scavenging activity, and increasing polyphenols; however, the essential oil content was negatively reduced by water stress. External citrulline further increased the activity of antioxidant enzymes. Citrulline application at 2 mM under severe water stress could also improve essential oil (EO) content in the first and second harvests by about 15 and 30%, respectively. Furthermore, under severe drought, citrulline at 2 mM could obtain the highest yield of isopinocamphone (47%) as the main component of EO. The results showed the high potential of this novel applied metabolite agent to be used in a well-fulfilled production of this medicinal plant.


Assuntos
Antioxidantes/metabolismo , Citrulina/farmacologia , Hyssopus/efeitos dos fármacos , Hyssopus/fisiologia , Óleos Voláteis/metabolismo , Canfanos/metabolismo , Catalase/metabolismo , Catecol Oxidase/metabolismo , Desidratação , Secas , Hyssopus/química , Óleos Voláteis/análise , Proteínas de Plantas/metabolismo , Plantas Medicinais/efeitos dos fármacos , Plantas Medicinais/fisiologia , Polifenóis/metabolismo , Superóxido Dismutase/metabolismo
16.
PLoS One ; 15(7): e0236507, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32730281

RESUMO

In air-breathing fish a reduction of gill surface area reduces the danger of losing oxygen taken up in the air-breathing organ (ABO) to hypoxic water, but it also reduces the surface area available for ion exchange, so that ion regulation may at least in part be transferred to other organs, like the kidney or the gut. In the air-breathing Arapaima gigas, gill lamellae regress as development proceeds, and starting as a water-breathing embryo Arapaima turns into an obligate air-breathing fish with proceeding development, suggesting that ion regulation is shifted away from the gills as the fish grows. In Arapaima the kidney projects medially into the ABO and thus, probably a unique situation among fishes, is in close contact to the gas of the ABO. We therefore hypothesized that the kidney would be predestined to adopt an increased importance for ion homeostasis, because the elevated ATP turnover connected to ion transport can easily be met by aerobic metabolism based on the excellent oxygen supply directly from the ABO. We also hypothesized that in gill tissue the reduced ion regulatory activity should result in a reduced metabolic activity. High metabolic activity and exposure to high oxygen tensions are connected to the production of reactive oxygen species (ROS), therefore the tissues exposed to these conditions should have a high ROS defense capacity. Using in vitro studies, we assessed metabolic activity and ROS production of gill, kidney and ABO tissue, and determined the activity of ROS degrading enzymes in small (~ 5g, 2-3 weeks old) and larger (~ 670 g, 3-4 months old) A. gigas. Comparing the three tissues revealed that kidney tissue oxygen uptake by far exceeded the uptake measured in gill tissue or ABO. ROS production was particularly high in gill tissue, and all three tissues had a high capacity to degrade ROS. Gill tissue was characterized by high activities of enzymes involved in the glutathione pathway to degrade ROS. By contrast, the tissues of the ABO and in particular the kidney were characterized by high catalase activities, revealing different, tissue-specific strategies in ROS defense in this species. Overall the differences in the activity of cells taken from small and larger fish were not as pronounced as expected, while at the tissue level the metabolic activity of kidney cells by far exceeded the activity of ABO and gill cells.


Assuntos
Peixes/fisiologia , Consumo de Oxigênio/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Animais , Brasil , Catalase/metabolismo , Brânquias/enzimologia , Brânquias/metabolismo , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Rim/metabolismo , Mitocôndrias/metabolismo , Superóxido Dismutase/metabolismo
17.
J Environ Sci Health B ; 55(9): 803-812, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32602772

RESUMO

Organophosphorus pesticides induce gender-specific developmental neurotoxicity after birth, especially in adolescents and adults. However, whether and when the selectivity occurs in fetus remains unclear. In this study, we analyzed chlorpyrifos (CPF)-induced neurotoxicity in the early fetal brains of male and female mice. The gestational dams were administered 0, 1, 3, and 5 mg/(kg.d) CPF during gestational days (GD)7-11, and brains from the fetuses were isolated and analyzed on GD12. Fetal gender was identified by PCR technique based on male-specific Sry gene and Myog control gene. The body weight and head weight, the activity of acetylcholinesterase (AChE), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), and the content of malondialdehyde (MDA), as well as the oxidative stress-related gene expression were examined. Our results showed that CPF pretreatment induced AChE inhibition in GD12 fetal brain. CPF treatment activated SOD and GPX but not CAT and MDA. For oxidative stress-related gene expression, CPF pretreatment increased mRNA expression of Sod1, Cat, Gpx1, and Gpx2 in the fetal brain on GD12. The statistical analysis did not show gender-selective CPF-induced toxicity. Moreover, our results showed that although the gestational exposure to CPF could elicit abnormalities in the early fetal brain, the toxicity observed was not gender-specific.


Assuntos
Encéfalo/efeitos dos fármacos , Encéfalo/embriologia , Clorpirifos/toxicidade , Inseticidas/toxicidade , Acetilcolinesterase/metabolismo , Animais , Peso Corporal/efeitos dos fármacos , Encéfalo/metabolismo , Catalase/genética , Catalase/metabolismo , Inibidores da Colinesterase/toxicidade , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Masculino , Malondialdeído/metabolismo , Camundongos Endogâmicos ICR , Síndromes Neurotóxicas/etiologia , Tamanho do Órgão/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , Fatores Sexuais , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Testes de Toxicidade/métodos
18.
PLoS One ; 15(7): e0236588, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32706804

RESUMO

Xanthoceras sorbifolia, a medicinal and oil-rich woody plant, has great potential for biodiesel production. However, little study explores the link between gene expression level and metabolite accumulation of X. sorbifolia in response to cold stress. Herein, we performed both transcriptomic and metabolomic analyses of X. sorbifolia seedlings to investigate the regulatory mechanism of resistance to low temperature (4 °C) based on physiological profile analyses. Cold stress resulted in a significant increase in the malondialdehyde content, electrolyte leakage and activity of antioxidant enzymes. A total of 1,527 common differentially expressed genes (DEGs) were identified, of which 895 were upregulated and 632 were downregulated. Annotation of DEGs revealed that amino acid metabolism, glycolysis/gluconeogenesis, starch and sucrose metabolism, galactose metabolism, fructose and mannose metabolism, and the citrate cycle (TCA) were strongly affected by cold stress. In addition, DEGs within the plant mitogen-activated protein kinase (MAPK) signaling pathway and TF families of ERF, WRKY, NAC, MYB, and bHLH were transcriptionally activated. Through metabolomic analysis, we found 51 significantly changed metabolites, particularly with the analysis of primary metabolites, such as sugars, amino acids, and organic acids. Moreover, there is an overlap between transcript and metabolite profiles. Association analysis between key genes and altered metabolites indicated that amino acid metabolism and sugar metabolism were enhanced. A large number of specific cold-responsive genes and metabolites highlight a comprehensive regulatory mechanism, which will contribute to a deeper understanding of the highly complex regulatory program under cold stress in X. sorbifolia.


Assuntos
Resposta ao Choque Frio/genética , Metaboloma , Metabolômica/métodos , Sapindaceae/metabolismo , Transcriptoma , Aminoácidos/metabolismo , Catalase/metabolismo , Temperatura Baixa , Regulação da Expressão Gênica de Plantas , Malondialdeído/metabolismo , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Análise de Componente Principal , RNA de Plantas/genética , RNA de Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Sapindaceae/genética , Transdução de Sinais/genética , Superóxido Dismutase/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
19.
Parasitol Res ; 119(9): 2783-2798, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32683559

RESUMO

Due to the increasing consumption of platinum (Pt), especially in automobile exhaust catalysts, environmental concentrations of Pt are of emerging concern worldwide. Limited information exists on environmental concentrations, particularly in Pt mining regions, while South Africa is the world's main supplier of Pt. Moreover, other metals are also released as by-products of Pt mining, which might also cause environmental concern. Certain fish parasite taxa have the ability to accumulate metals orders of magnitude higher than their hosts and can be used to reliably detect metals with naturally low abundance. Studies on Pt accumulation in parasite-host systems are limited. Therefore, the aims of the present study were (1) to determine the accumulation of a variety of metals (cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb), platinum (Pt), and zinc (Zn)) in helminth fish parasites compared with their hosts from a reference site and an impoundment impacted by Pt mining activities; (2) to assess whether there is a difference between bioaccumulation of metals in infected and uninfected hosts, as well as between hosts with different infection intensities; and (3) to compare the biomarker responses (acetylcholine esterase activity (AChE), metallothionein content (MT), catalase activity (CAT), reduced glutathione content (GSH), malondialdehyde content (MDA), protein carbonyls induction (PC), superoxide dismutase activity (SOD), and cellular energy allocation (CEA)) between infected and uninfected hosts. The cestode Atractolytocestus huronensis accumulated significantly higher concentrations of Cr, Ni, and Pt than their host Cyprinus carpio, while the nematode Contracaecum sp. accumulated significantly higher concentrations of Pt and Zn than their host Clarias gariepinus. Infected fish showed lower metal concentrations compared to uninfected fish, while the parasites had no significant effects on their hosts' biomarker responses. The parasites demonstrated the bioavailability of metals derived from Pt mining activities and their ability to resist its toxic effects. Thus, these parasites are promising sensitive accumulation indicators for Cr, Ni, Pb, and Pt contaminations from Pt mining activities.


Assuntos
Bioacumulação/fisiologia , Cestoides/química , Metais Pesados/análise , Nematoides/química , Emissões de Veículos/análise , Poluentes Químicos da Água/análise , Acetilcolinesterase/metabolismo , Animais , Cádmio/análise , Cádmio/toxicidade , Carpas/parasitologia , Catalase/metabolismo , Peixes-Gato/parasitologia , Cobre/análise , Cobre/toxicidade , Ecossistema , Monitoramento Ambiental , Glutationa/análise , Malondialdeído/análise , Metalotioneína/análise , Metais Pesados/toxicidade , Parasitos , Platina/análise , Platina/toxicidade , África do Sul , Superóxido Dismutase/metabolismo , Emissões de Veículos/toxicidade , Poluentes Químicos da Água/toxicidade
20.
Medicine (Baltimore) ; 99(26): e20433, 2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32590729

RESUMO

Bronchopulmonary dysplasia (BPD) is a chronic lung disease common in premature infants and is one of the leading causes of disability and death in newborns. The Keap-1/Nrf2 signaling pathway plays an important role in antioxidant and anti-inflammatory.Ten clean-grade, healthy pregnant Sprague-Dawley rats (purchased from Experimental Animal Center of Peking university, China) naturally gave birth to 55 neonatal rats from which 40 were selected and randomly divided into a hyperoxia group and a control group (N = 20, each). Thirty-two BPD patient samples are from Neonatal Department of the second Hospital of Jilin University from November 30, 2016 to May 1 2019.In present study, we observed that lung tissues of the control group did not undergo obvious pathological changes, whereas in the hyperoxia group, lung tissues had disordered structures. With increased time of hyperoxia exposure, the alveolar wall became attenuated. Under hypoxia conditions, the activity of oxidative stress-related enzymes (CAT, GSH-Px, SOD) in lung samples was significantly lower than that before treatment. The expression level of Keap1 mRNA and protein in the hyperoxia group was slightly lower than that of control group. The expression of Nrf2 and HO-1 mRNA and protein in the hyperoxia group was significantly higher than that of control group. For the infants with BPD, we found that the activity of SOD, GSH-Px, and CAT was significantly different from those of control group.We constructed a premature BPD animal model and found the abnormal of oxidative stress in different groups and the expression levels of Keap1/Nrf2 signaling pathway-related molecules, and we validated the results in premature infants with BPD.


Assuntos
Displasia Broncopulmonar/genética , Displasia Broncopulmonar/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Pulmão/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Animais , Animais Recém-Nascidos , Estudos de Casos e Controles , Catalase/metabolismo , Modelos Animais de Doenças , Feminino , Glutationa Peroxidase/metabolismo , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Humanos , Hiperóxia , Hipóxia , Recém-Nascido Prematuro , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Pulmão/patologia , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Fator 2 Relacionado a NF-E2/genética , Gravidez , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Transdução de Sinais , Superóxido Dismutase/metabolismo
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