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1.
Bioessays ; 41(5): e1900035, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30997694

RESUMO

This paper discusses how our bad reading habits are starting to influence how we write. This short abstract and the picture next to it summarize the arguments in this paper. Just kidding, they do not. One really needs to read the paper for that.


Assuntos
Leitura , Redação
2.
Bioessays ; 41(1): e1800206, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30485465

RESUMO

The overflow of scientific literature stimulates poor reading habits which can aggravate science's reproducibility crisis. Thus, solving the reproducibility crisis demands not only methodological changes, but also changes in our relationship with the scientific literature, especially our reading habits. Importantly, this does not mean reading more, it means reading better.


Assuntos
Leitura , Reprodutibilidade dos Testes , Pesquisa
3.
Fish Physiol Biochem ; 47(6): 1851-1864, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34562200

RESUMO

The Amazonian açai fruit (Euterpe oleracea) has shown promising anticonvulsant properties, comparable to those of diazepam (BDZ) in in vivo models submitted to pentylenetetrazole (PTZ). PTZ is a classic convulsant agent used in studies for the purpose of screening anticonvulsants and investigating the mechanisms of epilepsy. Herein, we aimed to determine, for the first time, the effect of dietary administration of lyophilized E. oleracea (LEO) on PTZ-induced seizures, using juvenile Colossoma macropomum fish (9.1 ± 1.5 g) as a model. A control diet (0.00% LEO) and two levels of LEO inclusion were established: 5.00% and 10.0% LEO (w/w). Fish were divided into five groups (n = 5): control (0.9% physiological solution; i.p.), PTZ (PTZ 150 mg kg-1; i.p.), PTZ LEO 5.00%, PTZ LEO 10.0%, and BDZ-PTZ (BDZ: diazepam 10 mg kg-1; i.p.). In addition to the electroencephalography (EEG), the lipid peroxidation (TBARS) was quantified in the brain, along with the characterization of behavioral responses. Fish receiving PTZ showed intense action potential bursts (APB), which overlapped with a hyperactive behavior. In PTZ LEO 5.00% and 10.0% groups, convulsive behavior was significantly reduced compared to the PTZ group. Fish fed 5.00% or 10.0% LEO and exposed to PTZ showed less excitability and lower mean amplitude in tracings. The inclusion of 10.0% LEO in the diet prevented the increase in mean amplitude of the EEG waves by 80%, without significant differences to the quantified mean amplitude of the BDZ-PTZ group. TBARS concentration was reduced by 60% in the brain of fish fed 10.0% LEO-enriched diets relative to the PTZ-administered group. The results of this study demonstrated the anticonvulsant and protective roles of LEO to the brain, and the dietary inclusion of LEO seems to be promising for the formulation of functional diets. Results of this study may boost the interest on the anti-seizurogenic properties of Euterpe oleracea, including the development of new approaches for the prevention of seizures in humans and animals with low epileptic threshold.


Assuntos
Anticonvulsivantes/uso terapêutico , Encéfalo/efeitos dos fármacos , Caraciformes , Euterpe , Convulsões , Animais , Diazepam/uso terapêutico , Dieta/veterinária , Euterpe/química , Peroxidação de Lipídeos , Pentilenotetrazol , Convulsões/induzido quimicamente , Convulsões/tratamento farmacológico , Convulsões/veterinária , Substâncias Reativas com Ácido Tiobarbitúrico
4.
Bioessays ; 40(11): e800068, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30176065

RESUMO

In recent years there has been a wealth of studies investigating how memories are allocated in the hippocampus. Some of those studies showed that it is possible to manipulate the identity of neurons recruited to represent a given memory without affecting the memory's behavioral expression. Those findings raised questions about how the hippocampus represents memories, with some researchers arguing that hippocampal neurons do not represent fixed stimuli. Herein, an alternative hypothesis is argued. Neurons in high-order brain regions can be tuned to multiple dimensions, forming complex, abstract representations. It is argued that such complex receptive fields allow those neurons to show some flexibility in their responses while still representing relatively fixed sets of stimuli. Moreover, it is pointed out that changes induced by artificial manipulation of cell assemblies are not completely redundant-the observed behavioral redundancy does not imply cognitive redundancy, as different, but similar, memories may induce the same behavior.


Assuntos
Cognição/fisiologia , Hipocampo/fisiologia , Memória Episódica , Memória/fisiologia , Animais , Humanos , Neurônios/fisiologia
5.
J Therm Biol ; 92: 102682, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32888581

RESUMO

The aim of this study was to verify the effects of the interaction between different temperatures and levels of dissolved oxygen in the oxidative stress parameters of pacu juveniles. A total of 81 pacu juveniles (61.7 ± 9.1 g) were exposed to three temperatures (18, 23, and 28 °C), acclimated for a period of 30 days, and then submitted to three levels of dissolved oxygen: control or normoxia (7 mg L-1); moderate hypoxia (4 mg L-1); and severe hypoxia (2 mg L-1) for 12 h. Glutathione-S-transferase (GST) activity, total antioxidant capacity against peroxyl radicals (ACAP), and protein thiol content (PSH) and LPO (lipid peroxidation) [measured by the TBARS] were measured in gill, liver, muscle and brain. The results indicated that the interaction between different temperatures and dissolved oxygen levels caused alterations in the antioxidant system and induced lipid and protein damage in pacu juveniles. In addition, the effects were organ specific. In conclusion, exposure to moderate and severe hypoxia affect oxidative stress parameters and have been shown to be organ-specific in pacu juveniles. The interaction between 23 °C and hypoxia caused greater disturbances in oxidative stress markers, such as PSH in the gills and liver and LPO in the muscle.


Assuntos
Caraciformes/fisiologia , Estresse Oxidativo , Oxigênio/metabolismo , Animais , Proteínas de Peixes/metabolismo , Brânquias/fisiologia , Glutationa Transferase/metabolismo , Peroxidação de Lipídeos , Fígado/fisiologia , Temperatura
6.
Chem Res Toxicol ; 32(4): 566-577, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30868869

RESUMO

We present an in silico approach for modeling the noncovalent interactions between the human mitochondrial voltage-dependent anion channel (hVDAC1) and a family of single-walled carbon nanotubes (SWCNTs) with a defined pattern of topological vacancies ( v = 1-16), obtained by removing atoms from the SWCNT surface. The general results showed more stable docking interaction complexes (SWCNT-hVDAC1), with more negative Gibbs free energy of binding affinity values, and a strong dependence on the vacancy number ( R2 = 0.93) and vacancy formation energy ( R2 = 0.96). In addition, for most of the SWCNT vacancies that were analyzed, the interatomic distances for the interactions of the SWCNT-hVDAC1 complex with the functional catalytic residues (i.e., Pro7, Gln199, Gln182, Phe181, Val20, Asp19, Lys15, Gly14, Asp12, Ala11, and Arg18) that form the hVDAC1 active site (i.e., the voltage-sensing N-terminal α-helix segment) were very similar to or shorter than the interatomic distances of these residues for ATP-hVDAC1 interactions. In particular, the hVDAC1 residues that can be phosphorylated like Tyr10, Tyr198, and Se16 were significantly perturbed by the interactions with SWCNT with at least nine vacancies. In addition, the SWCNT vacancy family members can affect the flexibility properties of the hVDAC1 N-terminal α-helix segment inducing different patterns of local perturbations in inter-residue communication. Finally, vacancy quantitative structure-binding relationships (V-QSBRs) were unveiled for setting up a robust model that can predict the strength of docking interactions between SWCNTs with a specific topological vacancy and hVDAC1. The developed V-QSBR model classified properly all of the SWCNTs with a different number of SWCNT vacancies with exceptional sensitivity and specificity (both equal to 100%), indicating a strong potential to unequivocally predict the influence of SWCNT vacancies on the mitochondrial channel interactions.


Assuntos
Mitocôndrias/química , Simulação de Acoplamento Molecular , Nanotubos de Carbono/química , Canal de Ânion 1 Dependente de Voltagem/química , Humanos , Relação Estrutura-Atividade
7.
J Chem Inf Model ; 59(1): 86-97, 2019 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-30408958

RESUMO

Recently, it has been suggested that the mitochondrial oligomycin A-sensitive F0-ATPase subunit is an uncoupling channel linked to apoptotic cell death, and as such, the toxicological inhibition of mitochondrial F0-ATP hydrolase can be an interesting mitotoxicity-based therapy under pathological conditions. In addition, carbon nanotubes (CNTs) have been shown to offer higher selectivity like mitotoxic-targeting nanoparticles. In this work, linear and nonlinear classification algorithms on structure-toxicity relationships with artificial neural network (ANN) models were set up using the fractal dimensions calculated from CNTs as a source of supramolecular chemical information. The potential ability of CNT-family members to induce mitochondrial toxicity-based inhibition of the mitochondrial H+-F0F1-ATPase from in vitro assays was predicted. The attained experimental data suggest that CNTs have a strong ability to inhibit the F0-ATPase active-binding site following the order oxidized-CNT (CNT-COOH > CNT-OH) > pristine-CNT and mimicking the oligomycin A mitotoxicity behavior. Meanwhile, the performance of the ANN models was found to be improved by including different nonlinear combinations of the calculated fractal scanning electron microscopy (SEM) nanodescriptors, leading to models with excellent internal accuracy and predictivity on external data to classify correctly CNT-mitotoxic and nonmitotoxic with specificity (Sp > 98.9%) and sensitivity (Sn > 99.0%) from ANN models compared with linear approaches (LNN) with Sp ≈ Sn > 95.5%. Finally, the present study can contribute toward the rational design of carbon nanomaterials and opens new opportunities toward mitochondrial nanotoxicology-based in silico models.


Assuntos
Simulação por Computador , Inibidores Enzimáticos/química , Mitocôndrias/enzimologia , Nanotubos de Carbono/química , ATPases Translocadoras de Prótons/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Nanotubos de Carbono/toxicidade , Redes Neurais de Computação , Relação Estrutura-Atividade
8.
Environ Res ; 178: 108683, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31539823

RESUMO

As a consequence of their unique characteristics, the use of Engineered Nanomaterials (ENMs) is rapidly increasing in industrial, agricultural products, as well as in environmental technology. However, this fast expansion and use make likely their release into the environment with particular concerns for the aquatic ecosystems, which tend to be the ultimate sink for this type of contaminants. Considering the settling behaviour of particulates, benthic organisms are more likely to be exposed to these compounds. In this way, the present review aims to summarise the most recent data available from the literature on ENMs behaviour and fate in aquatic ecosystems, focusing on their ecotoxicological impacts towards marine and estuarine bivalves. The selection of ENMs presented here was based on the OECD's Working Party on Manufactured Nanomaterials (WPMN), which involves the safety testing and risk assessment of ENMs. Physical-chemical characteristics and properties, applications, environmental relevant concentrations and behaviour in aquatic environment, as well as their toxic impacts towards marine bivalves are discussed. Moreover, it is also identified the impacts derived from the simultaneous exposure of marine organisms to ENMs and climate changes as an ecologically relevant scenario.


Assuntos
Bivalves , Nanoestruturas/química , Poluentes Químicos da Água/química , Animais , Organismos Aquáticos , Ecossistema , Ecotoxicologia , Nanoestruturas/toxicidade , Poluentes Químicos da Água/toxicidade
9.
Ecotoxicol Environ Saf ; 147: 151-156, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28841531

RESUMO

Phytoremediation is a low cost technology based on the use of plants to remove a wide range of pollutants from the environment, including the insecticide DDT. However, some pollutants are known to enhance generation of reactive oxygen species (ROS), which can generate toxic effects on plants affecting the phytoremediation efficiency. This study aims to analyze the potential use of antioxidant responses as a measure of tolerance to select plants for phytoremediation purposes. Tomato and zucchini plants were grown for 15 days in soils contaminated with DDTs (DDT + DDE + DDD). Protein content, glutathione-S-transferase (GST), glutathione reductase (GR), glutathione peroxidase (GPx) and catalase (CAT) activities were measured in plant tissues. Exposure to DDTs did not affect protein content or CAT activity in any of the species. GST, GR and GPx activity showed different responses in exposed and control tomato plants. After DDTs exposure, tomato showed increased GR and GPX activity in stems and leaves, respectively, and a decrease in the GST activity in roots. As no effects were observed in zucchini, results suggest different susceptibility and/or defense mechanisms involved after pesticide exposure. Finally, both species differed also in terms of DDTs uptake and translocation. The knowledge about antioxidant responses induced by pesticides exposure could be helpful for planning phytoremediation strategies and for the selection of tolerant species according to particular scenarios.


Assuntos
Antioxidantes/metabolismo , Cucurbita/efeitos dos fármacos , DDT/toxicidade , Poluentes do Solo/toxicidade , Solanum lycopersicum/efeitos dos fármacos , Biodegradação Ambiental , Cucurbita/enzimologia , DDT/metabolismo , Solanum lycopersicum/enzimologia , Solo/química , Poluentes do Solo/metabolismo
10.
Hippocampus ; 27(9): 937-950, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28597491

RESUMO

The generation of new neurons in the hippocampus of adult mammals has become a widely accepted phenomenon, but the functional significance of the adult neurogenesis in the hippocampus is not fully understood. One of the main hypotheses currently investigated suggests that neurogenesis contributes to pattern separation in the dentate gyrus. Many behavioral studies were conducted aiming to test this hypothesis using rodents as animal model. In those studies, researches ablated neurogenesis in the animals and subsequently evaluate them in tests of behavioral pattern separation, that is, behaviors that are thought to rely on the computational process of pattern separation. The results of these studies are varied, with most supporting a role for neurogenesis in pattern separation, but some others not. To address this controversy we performed a systematic review and meta-analysis of studies evaluating the effect of neurogenesis ablation on behavioral pattern separation. Analysis results indicated that most of the literature in the topic is surprisingly consistent and, although there are two studies with divergent results, the bulk of the literature supports an effect of hippocampal neurogenesis on behavioral pattern separation. We discuss those findings in light of other behavioral effects of hippocampal neurogenesis ablation, limitations of behavioral data and other lines of evidence about the effect of hippocampal neurogenesis in the dentate gyrus.


Assuntos
Hipocampo/citologia , Hipocampo/fisiologia , Neurogênese/fisiologia , Neurônios/fisiologia , Animais , Bases de Dados Bibliográficas/estatística & dados numéricos , Humanos
11.
An Acad Bras Cienc ; 89(3 Suppl): 2209-2218, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28746612

RESUMO

The present study aimed to evaluate the effects of benzocaine and tricaine methanesulfonate on oxidative stress parameters of juvenile tambaqui tissues. Fish (n=80) were anesthetized with benzocaine (100 mg L-1) or tricaine (240 mg L-1) and two control groups were used (non-anesthetized fish and fish exposed to ethanol-only). After anesthetic induction 10 fish/anesthetic were euthanized after 3, 12 and 24 hours post-anesthesia and tissue samplings (gills, liver and brain) were performed. Samples were submitted to analyses of enzyme activity glutathione-S-transferase (GST), cellular lipid peroxidation (TBARS) and total antioxidant capacity (ACAP). ACAP increased in gills of benzocaine treatment after 12 hours. The liver showed a reduction in ACAP of tricaine treatment after 12 hours. Both anesthetic treatments showed an increase of ACAP at 24 hours compared to control group. The activity of the GST enzyme increased in the gills for treatments benzocaine and tricaine after 3 and 12 hours. Liver showed increased GST activity (benzocaine after 24 hours and tricaine after 3 and 24 hours). Lipid damage decreased in gills (both anesthetics) and brain (tricaine) after 24 hours. The results demonstrate that benzocaine and tricaine did not cause oxidative damage in juvenile tambaqui under the experimental conditions herein established.


Assuntos
Aminobenzoatos/farmacologia , Anestésicos/farmacologia , Benzocaína/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Anestésicos/administração & dosagem , Animais , Encéfalo/efeitos dos fármacos , Peixes , Brânquias/efeitos dos fármacos , Fígado/efeitos dos fármacos
12.
Pestic Biochem Physiol ; 130: 17-21, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27155479

RESUMO

Phytoremediation is a low-cost alternative technology based on the use of plants to remove pollutants from the environment. Persistent organic pollutants such as DDTs with a long half-life in soils are attractive candidates for remediation. This study aimed to determine the potential of antioxidant response use in the evaluation of plants' tolerance for selecting species in phytoremediation purposes. Alfalfa and soybean plants were grown in DDT contaminated soils. After 60days, growth, protein content, antioxidant capacity, GST activity, concentration of proteic and non-proteic thiol groups, chlorophyll content and carotenoid content were measured in plant tissues. Results showed no effect on alfalfa or soybean photosynthetic pigments but different responses in the protein content, antioxidant capacity, GST activity and thiol groups on roots, stems and leaves, indicating that DDTs affected both species. Soybean showed higher susceptibility than alfalfa plants due to the lower antioxidant capacity and GST activity in leaves, in spite of having the lowest DDT accumulation. This study provides new insights into the role of oxidative stress as an important component of the plant's response to DDT exposure.


Assuntos
Antioxidantes/metabolismo , Biodegradação Ambiental , DDT/metabolismo , Glycine max/metabolismo , Medicago sativa/metabolismo , Poluentes do Solo/metabolismo , Carotenoides/metabolismo , Clorofila/metabolismo , Glutationa Transferase/metabolismo
13.
Ecotoxicol Environ Saf ; 89: 182-8, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23273620

RESUMO

In situ translocation experiments are advantageous relative to traditional laboratory experiments, particularly for understanding the bioavailability of trace metals like mercury (Hg). Individuals of the polychaete Perinereis gualpensis were translocated from a reference site (Raqui estuary, Chile) to an estuarine site with significant sediment Hg concentrations (Lenga estuary: 1.78-9.89 mg/kg). Individuals were exposed in polluted and non-polluted sediments for 21 days and sampled every 7 days with cages deployed at three different depths. Tissue Hg concentrations were measured in conjunction with oxidative stress responses. Translocated polychaetes rapidly accumulated Hg. Glutathione S-transferase (GST) activities measured from posterior body regions were 2-fold higher than control activities after 21 days of exposure. Other antioxidant measures were idiosyncratic. Distinct burrowing behavior differences were observed; control polychaetes exhibited more homogenous vertical distributions, whereas in Lenga, worms tended to remain in upper layers. These studies demonstrate that under natural conditions, Hg is highly bioavailable to polychaetes affecting both biochemical and behavioral responses after relatively short-term exposure.


Assuntos
Comportamento Animal/efeitos dos fármacos , Poliquetos/efeitos dos fármacos , Poluentes do Solo/toxicidade , Animais , Disponibilidade Biológica , Chile , Exposição Ambiental , Monitoramento Ambiental , Ativação Enzimática/efeitos dos fármacos , Sedimentos Geológicos/química , Glutationa Transferase/metabolismo , Mercúrio/análise , Mercúrio/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Água do Mar/química , Poluentes do Solo/análise , Fatores de Tempo
14.
Aquat Toxicol ; 246: 106148, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35364510

RESUMO

Saxitoxin (STX) is a neurotoxic cyanotoxin that also generate reactive oxygen species, leading to a situation of oxidative stress and altered metabolism. The Amazonian fruit açaí Euterpe oleracea possesses a high concentration of antioxidant molecules, a fact that prompted us to evaluate its chemoprotection activity against STX toxicity (obtained from samples of Trichodesmium sp. collected in the environment) in the shrimp Litopenaeus vannamei. For 30 days, shrimps were maintained in 16 aquaria containing 10 shrimps (15% salinity, pH 8.0, 24 °C, 12C/12D photoperiod) and fed twice daily with a diet supplemented with lyophilized açaí pulp (10%), in addition to the control diet. After, shrimps (7.21 ± 0.04 g) were exposed to the toxin added to the feed for 96 h. Four treatments were defined: CTR (control diet), T (lyophilized powder of Trichodesmium sp. 0.8 µg/g), A (10% of açaí) and the combination T + A. HPLC analysis showed predominance of gonyautoxin-1 concentrations (GTX-1) and gonyautoxin-4 concentrations (GTX-4). The results of molecular docking simulations indicated that all variants of STX, including GTX-1, can be a substrate of isoform mu of the glutathione-S-transferase (GST) enzyme since these molecules obtained similar values of estimated Free Energy of Binding (FEB), as well as similar final positions on the binding site. GSH levels were reduced in muscle tissues of shrimp in the T, A, and T + A treatments. Increased GST activity was observed in shrimp hepatopancreas of the T treatment and the gills of the A and T + A treatments. A decrease of protein sulfhydryl groups (P-SH) was observed in gills of shrimps from T + A treatment. A reduction in malondialdehyde (MDA) levels was registered in the hepatopancreas of the T + A treatment in respect to the Control, T, and A treatments. The use of açaí supplements in L. vannamei feed was able to partially mitigate the toxic effects caused by Trichodesmium sp. extracts, and points to mu GST isoform as a key enzyme for saxitoxin detoxification in L. vannamei, an issue that deserves further investigation.


Assuntos
Euterpe , Penaeidae , Poluentes Químicos da Água , Animais , Euterpe/química , Simulação de Acoplamento Molecular , Saxitoxina/toxicidade , Poluentes Químicos da Água/toxicidade
15.
Ecotoxicol Environ Saf ; 74(3): 211-8, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21112631

RESUMO

Arsenic (As) is a widespread pollutant in the world and its toxicity is related to its chemical form, with inorganic forms being considered more toxic than the organic form, and huge differences in effects and processes of metabolism. This paper reviews the potential biochemical mechanisms of uptake of arsenic by aquaporins, capacity for metabolism and cellular efflux of As. It is known that As can affect signaling pathways since it can activate proteins such as ERK2, p38 and JNK, as shown in mammals. A comparison between phosphorylation sites of these proteins is presented in order to determine whether the same effect triggered by As in mammals might be observed in aquatic animals. The toxicity resulting from As exposure is considered to be linked to an imbalance between pro-oxidant and antioxidant homeostasis that results in oxidative stress. So, present review analyzes examples of oxidative stress generation by arsenic. Biotransformation of As is a process where firstly the arsenate is converted into arsenite and then transformed into mono-, di-, and trimethylated products. In the methylation process, the role of the omega isoform of glutathione-S-transferase (GST) is discussed. In addition, a phylogenetic tree was constructed for aquaporin proteins of different species, including aquatic animals, taking into account their importance in trivalent arsenic uptake.


Assuntos
Organismos Aquáticos/efeitos dos fármacos , Arsênio/toxicidade , Mamíferos/metabolismo , Poluentes Químicos da Água/toxicidade , Animais , Organismos Aquáticos/metabolismo , Arsênio/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Estresse Oxidativo , Transdução de Sinais/efeitos dos fármacos , Poluentes Químicos da Água/metabolismo
16.
Arch Environ Contam Toxicol ; 61(2): 311-7, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21072630

RESUMO

Bacteria communities living in mucus secretions of common carp Cyprinus carpio (Cyprinidae) were exposed to the organic nanomaterial fullerene (C(60)) to evaluate its potential bactericidal effects. End points analyzed were viability, growth, reactive oxygen species (ROS) concentration, and total antioxidant competence against peroxyl radicals. Viability was not affected (p > 0.05), whereas growth was arrested (p < 0.05) after 3 hours of exposure to the three concentration of C(60) assayed (0.1, 1, and 10 mg/L). Levels of RO measured at different C(60) concentration showed that some colonies were reactive (significant dose-response relation, p < 0.05) to C(60), whereas others were not. The nonreactive colonies to C(60) presented higher antioxidant competence to peroxyl radicals compared with the reactive colonies (p < 0.05). The strains isolated and identified by polymerase chain reaction (PCR) products of 16S rRNA showed a predominance of Aeromonas genus between all the isolated Gram-negative bacteria. Thus, the present results indicate that C(60) affects bacterial communities that live in mucus secretions of common carp.


Assuntos
Aeromonas/crescimento & desenvolvimento , Antioxidantes/farmacologia , Carpas/microbiologia , Exposição Ambiental/análise , Fulerenos/farmacologia , Muco/microbiologia , Nanoestruturas/química , Aeromonas/efeitos dos fármacos , Aeromonas/metabolismo , Animais , Antibacterianos/farmacologia , Carpas/metabolismo , Fulerenos/química , Muco/metabolismo , Peróxidos/metabolismo , Reação em Cadeia da Polimerase
17.
Mar Biotechnol (NY) ; 23(6): 881-891, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34714442

RESUMO

The animals from bycatch of the shrimp fisheries can be a source of natural products and bioactive compounds. Thus, the present study aimed to evaluate the bioactivity of protein hydrolysates prepared from the two most abundant crabs from the bycatch of shrimp fisheries in Brazil (Callinectes ornatus and Hepatus pudibundus). Samples of C. ornatus and H. pudibundus were collected in the region of Ubatuba, State of São Paulo, Brazil. Muscles with small pieces of exoskeleton of both species were hydrolyzed using two enzymes, Alcalase 2.4 L® or Protamex®. The in vitro antioxidant capacity was analyzed used three methods: DPPH, sulfhydryl groups, and peroxyl radicals. Additionally, the cytotoxicity of the hydrolysates was investigated using pre-osteoblasts cells. The results showed that the degree of hydrolysis (DH) of H. pudibundus was superior to DH of C. ornatus using both enzymes and was higher when using the enzyme Alcalase 2.4 L® (32.0% ± 1.9). The analysis suggested that the hydrolysates have antioxidant activity. Besides that, no cytotoxic effect was observed on cell viability. Thus, protein hydrolysates of C. ornatus and H. pudibundus have bioactivity, which add value to these bycatch species and suggests their potential use as nutraceutical ingredient in the food industry.


Assuntos
Hidrolisados de Proteína , Alimentos Marinhos , Animais , Antioxidantes/farmacologia , Brasil , Pesqueiros , Hidrólise , Hidrolisados de Proteína/química
18.
Food Chem ; 342: 128361, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33077277

RESUMO

Shrimp trawling is an important socio-economic activity; however, the bycatch can be problematic to the environment. Thus, the present study investigated potential uses of the bycatch to generate value-added products. The biological activity of the protein hydrolysates obtained from the two most abundant fish species (Micropogonias furnieri and Paralonchurus brasiliensis) was evaluated. Muscle and skin samples of both species were hydrolyzed using two enzymes, Alcalase 2.4 L® or Protamex®. The in vitro antioxidant capacity against peroxyl radicals, DPPH, and sulfhydryl groups were analyzed. Cell viability, Western Blotting, Zymogram, and Real-time PCR analyses were performed. The results showed that the hydrolysates have antioxidant activity and no effect on cell viability at doses lower than 16 mg/mL. In addition, they can modulate extracellular remodelling and intracellular pathways related to cell adhesion. Thus, the hydrolysis of the fish bycatch allows the release of bioactive peptides with potential use in the food industry.


Assuntos
Antioxidantes/farmacologia , Pesqueiros , Peixes , Hidrolisados de Proteína/farmacologia , Animais , Antioxidantes/metabolismo , Peixes/metabolismo , Peptídeos/farmacologia , Hidrolisados de Proteína/metabolismo , Alimentos Marinhos , Subtilisinas/metabolismo
19.
Artigo em Inglês | MEDLINE | ID: mdl-33164844

RESUMO

The use of carbon nanomaterials (CNMs) is growing in different technological fields, raising concern on their potential impacts on the environment. Given its diverse nanothenological applications, graphene oxide (GO) stands out among the most widely used CNMs. Its hydrophilic capacity enables it to remain stable in suspension in water allowing that GO can be accessible for accumulation by aquatic organisms through ingestion, filtration and superficial dermal contact when present in aquatic ecosystems. Considering that the effects induced to aquatic organisms may depend on environment characteristics, such as temperature, salinity, water pH as well as the presence/absence of sediment, the present study aimed to investigate the influence of sediment on the impacts caused by GO exposure. For this, oxidative stress parameters were measured in the clam Ruditapes philippinarum, exposed to different GO concentrations (0.01, 0.1 and 1 mg/L), in the presence and absence of sediment, for a 28-days experimental period. The results here presented showed that regardless the presence or absence of sediment, most of the biochemical parameters considered were altered when clams were exposed to the highest concentration. The present findings further revealed that in the presence of sediment, clams mostly invested in non-enzymatic defenses (such as reduced glutathione, GSH), while animals exposed to GO in the absence of sediment favored their enzymatic antioxidant defense capacity (catalase, CAT and superoxide dismutase, SOD). This study highlights the relevance of environmental variations as key factors influencing organisms' responses to pollutants.


Assuntos
Bivalves/efeitos dos fármacos , Sedimentos Geológicos/química , Grafite/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/metabolismo , Bivalves/metabolismo , Catalase/metabolismo , Relação Dose-Resposta a Droga , Ecossistema , Glutationa/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Fatores de Tempo
20.
Environ Sci Pollut Res Int ; 27(25): 30945-30956, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31808098

RESUMO

Carbon nanomaterials (CNM), such as graphene oxide (GO), have been the focus of study in several areas of science mostly due to their physical-chemical properties. However, data concerning the potential toxic effects of these CNM in bivalves are still scarce. When present in the aquatic systems, the combination with other contaminants, as well as pH environmental variations, can influence the behavior of these nanomaterials and, consequently, their toxicity. Thus, the main goal of this study was to evaluate the effect of exposure of clam Ruditapes philippinarum to GO when acting alone and in the combination with copper (Cu), under two pH levels (control 7.8 and 7.3). A 28-day exposure was performed and metabolism and oxidative stress-related parameters were evaluated. The effects caused by GO and Cu exposures, either isolated or co-exposed, showed a direct and dependent relationship with the pH in which the organisms were exposed. In clams maintained at control pH (7.8), Cu and GO + Cu treatments showed lower lipid peroxidation (LPO) and lower electron transport system (ETS) activity, respectively. In clams maintained at low pH, glutathione-S-transferases (GSTs) activities were increased in Cu and Cu + GO treatments, whereas reduced glutathione (GSH) levels were increased in Cu treatment and ETS activity was higher in GO + Cu. Thus, it can be observed that clams responses to Cu and GO were strongly modulated by pH in terms of their defense system and energy production, although this does not result into higher LPO levels.


Assuntos
Bivalves , Poluentes Químicos da Água/análise , Animais , Cobre , Grafite , Concentração de Íons de Hidrogênio
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