Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 26
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
J Toxicol Environ Health A ; 87(8): 342-356, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38310537

RESUMO

The assessment of amphibian responses as bioindicators of exposure to chemical pollutants is an important tool for conservation of native species. This study aimed to investigate the effects of chronic aluminum (Al) and zinc (Zn) exposure on survival, body size, morphology (malformations), and immune system (leukocyte profile) in P. cuvieri tadpoles. Ecotoxicological analyses were performed utilizing chronic toxicity tests in which 210 tadpoles at the 25th Gosner developmental stage were exposed to Al and Zn. Individuals of P. cuvieri were maintained in glass containers containing various concentrations of aluminum sulfate (0.1, 0.2, or 0.3 mg/L) and zinc sulfate (0.18, 0.27 or 0.35 mg/L), and tests were performed in triplicate. After 14 days, amphibians were weighed, measured and survival rate, malformations in the oral and intestine apparatus, leukocyte profile, and ratio between neutrophils and lymphocytes determined. The differing concentrations of Al and Zn did not produce lethality in P. cuvieri where 95% of the animals survived 326 hr following metal exposure. Individuals exposed to Zn achieved greater body growth and weight gain compared to controls. Aluminum increased weight gain compared controls. These metals also produced malformations of the oral and intestine apparatus and enhanced occurrence of hemorrhages, especially at the highest doses. Lymphocytes were the predominant cells among leukocytes, with lymphopenia and neutrophilia observed following Al and Zn treatment, as evidenced by elevated neutrophil/lymphocyte ratio, an important indicator of stress in animals. Data suggest that further studies need to be carried out, even with metal concentrations higher than those prescribed by CONAMA, to ensure the conservation of this species.


Assuntos
Poluentes Químicos da Água , Zinco , Humanos , Animais , Zinco/farmacologia , Zinco/toxicidade , Alumínio/farmacologia , Larva , Anuros/fisiologia , Metais , Sistema Imunitário/química , Tamanho Corporal , Aumento de Peso , Poluentes Químicos da Água/toxicidade
2.
Artigo em Inglês | MEDLINE | ID: mdl-38218566

RESUMO

Amphibians are considered bioindicators of the environment due to their high sensitivity and involvement in terrestrial and aquatic ecosystems. In the last two decades, 2,4-D has been one of the most widely used herbicides in Brazil and around the world, as its use has been authorized for genetically modified crops and therefore has been detected in surface and groundwater. Against this background, the aim of this work was to investigate the effects of environmentally relevant concentrations of 2,4-D-based herbicides on survival, malformations, swimming activity, presence of micronuclei and erythrocyte nuclear abnormalities in Physalaemus cuvieri tadpoles. The amphibians were exposed to six concentrations of 2,4-D-based herbicides: 0.0, 4.0, 30.0, 52.5, 75.0, and 100 µg L-1, for 168 h. At concentrations higher than 52.5 µg L-1, significantly increased mortality was observed from 24 h after exposure. At the highest concentration (100 µg L-1), the occurrence of mouth and intestinal malformations was also observed. The occurrence of erythrocyte nuclear abnormalities at concentrations of 30.0, 52.5, 75.0 and 100 µg L-1 and the presence of micronuclei at concentrations of 52.5, 75.0, and 100 µg L-1 were also recorded. These effects of 2,4-D in P. cuvieri indicate that the ecological risk observed at concentrations above 10.35 µg L-1 2,4-D may represent a threat to the health and survival of this species, i.e., exposure to 2,4-D at concentrations already detected in surface waters in the species' range is toxic to P. cuvieri.


Assuntos
Herbicidas , Poluentes Químicos da Água , Animais , Herbicidas/toxicidade , Ecossistema , Larva , Produtos Agrícolas , Plantas Geneticamente Modificadas , Anuros , Ácido 2,4-Diclorofenoxiacético , Poluentes Químicos da Água/toxicidade
3.
Sci Rep ; 13(1): 9813, 2023 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-37330587

RESUMO

The use of terpenoid compounds in different neural-related conditions is becoming useful for several illnesses. Another possible activity of these compounds is the reduction of nervous impairment. Cannabis sativa plants are known for their concentration of two important terpenoids, the delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD). CBD and THC have central peripheral activities already described and their usage in different brain diseases, such as Alzheimer's and multiple sclerosis. Aluminum (Al) is known as an important neurotoxic compound, the physiological action of Al is not known already, and in high concentrations can lead to intoxication and cause neurotoxicity. Here we evaluated the potential effect of two different doses of CBD- and THC-rich based oils against Al-induced toxicity, in the zebrafish model. We evaluated behavioral biomarkers of the novel tank test (NTT) and social preference test (SPT), and biochemical markers: the activity of the enzyme acetylcholinesterase (AChE) and the antioxidant enzymes-catalase, superoxide dismutase, and glutathione-S-transferase. CBD- and THC-based oils were able to increase the AChE activity helping the cholinergic nervous system actuate against Al toxicity which was reflected by the behavioral biomarkers changes. We concluded that the oils have a protective effect and might be used with proposals for neurological and antioxidant impairment avoidance caused by Al intoxications.


Assuntos
Canabidiol , Cannabis , Animais , Cannabis/química , Alumínio , Antioxidantes , Acetilcolinesterase , Peixe-Zebra , Canabidiol/farmacologia , Óleos , Dronabinol/farmacologia
4.
Artigo em Inglês | MEDLINE | ID: mdl-37192702

RESUMO

The growing consumption of psychoactive drugs, such as Venlafaxine (VFX), can negatively affect the organisms. Our main hypothesis is to investigate if VFX at human-used doses could exert effects on the behavioral, nervous, and antioxidant systems of two different organisms, zebrafish and C. elegans. We evaluated the effect of acute exposure to VFX at four concentrations (0, 37.5, 75, and 150 mg L-1) using toxicological indicator assessments. We evaluated zebrafish behavior using the novel tank test (NTT), social preference test (SPT), cortisol levels, acetylcholinesterase (AChE) activity, and antioxidant system. In C. elegans, we evaluated body bends, defecation cycles, pharyngeal pumping, AChE activity, and antioxidant system. C. elegans do not show alterations in the behavior analysis of pharyngeal pumping and body bends. Instead, the defecation cycle was increased in the highest dose of VFX. AChE activity also does not have differences compared to the control, the same occurs in lipid peroxidation rates. These results showed that nematodes were more resistant to changes when exposed to VFX. Zebrafish exposed to VFX showed changes in the NTT and SPT test, mainly in the anxiolytic pattern, suggesting that VFX alters this anxiolytic-like behavior. Comparing both organisms, we can observe that zebrafish seems to be more sensitive in this neurotoxicological evaluation.


Assuntos
Ansiolíticos , Peixe-Zebra , Animais , Humanos , Cloridrato de Venlafaxina/toxicidade , Caenorhabditis elegans , Acetilcolinesterase , Antioxidantes
5.
Environ Sci Pollut Res Int ; 30(29): 73662-73676, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37195604

RESUMO

The imidacloprid-based insecticides (IBIs) are among the most used insecticides worldwide, and chronic and acute toxic effects (days exposure protocols) have been reported in several species in studies of IBIs at lethal concentrations. However, there is little information on shorter time exposures and environmentally relevant concentrations. In this study, we investigated the effect of a 30-min exposure to environmentally relevant concentrations of IBI on the behavior, redox status, and cortisol levels of zebrafish. We showed that the IBI decreased fish locomotion and social and aggressive behaviors and induced an anxiolytic-like behavior. Furthermore, IBI increased cortisol levels and protein carbonylation and decreased nitric oxide levels. These changes were mostly observed at 0.013 and 0.0013 µg·L-1 of IBI. In an environmental context, these behavioral and physiological disbalances, which were immediately triggered by IBI, can impair the ability of fish to evade predators and, consequently, affect their survival.


Assuntos
Inseticidas , Poluentes Químicos da Água , Animais , Inseticidas/toxicidade , Inseticidas/metabolismo , Peixe-Zebra/fisiologia , Hidrocortisona , Neonicotinoides/toxicidade , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/metabolismo
6.
Artigo em Inglês | MEDLINE | ID: mdl-37172752

RESUMO

The use of agrichemical pyrethroid-based insecticides to combat crop infestations and ectoparasites in animals is increasing. In this context, two pyrethroid-based insecticides are widely used, λ-cyhalothrin and Cypermethrin. The mechanism of action of these insecticides is characterized by the opening of ion channels and death by neural hyperexcitability. In this study, we evaluated the toxicological effect of two pyrethroid-based insecticides λ-cyhalothrin and Cypermethrin in C. elegans aiming to evaluate the transgenerational (TG), neonatal (NN) and lifespan (LS) effects of these compounds. At the end of each exposure period, were evaluated behavioral biomarkers of body bends, pharyngeal pumping, and feeding behavior. Furthermore, the fluorescent expression of antioxidant enzymes (superoxide dismutase, catalase, and glutathione-S-transferase) and the fluorescent expression of PolyQ40 aggregates were quantified. Lastly, the activity of the enzyme acetylcholinesterase (AChE) was quantified. Changes in TG were more related to changes in AChE enzyme activity that probably were transferred to the offspring, altering behavioral biomarkers in the adult life of offspring from exposed parents. However, alterations in LS were related to the modulation of ion channels in a chronic way, exerting behavioral effects. In addition, both compounds increased the expression of PolyQ40 muscle aggregates in mutant worms. These proteins are related to the increased probability of the senile incidence of Huntington's Disease in genetically predisposed patients.


Assuntos
Inseticidas , Piretrinas , Animais , Inseticidas/toxicidade , Caenorhabditis elegans/metabolismo , Acetilcolinesterase/metabolismo , Piretrinas/toxicidade , Nitrilas , Canais Iônicos , Biomarcadores/metabolismo
7.
Environ Pollut ; 327: 121530, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37004863

RESUMO

Pyrethroids prallethrin (P-BI) and transfluthrin (T-BI) are among the most commonly used molecules with insecticide action. These molecules comprise different formulations of insecticides largely used in household, agricultural, and animal production fields. However, the increased use of these molecules has led to concerns regarding their safety in animals and humans. Oxidative stress (OS) is believed to be easily established by xenobiotic contacts, such as pyrethroids. We aimed to evaluate and understand the impact of two household insecticides and two doses applied to different tissues of the antioxidant system of zebrafish (Danio rerio). We observed that the effect on the antioxidant system differed between tissues. The muscle was the most affected tissue in the body, the antioxidant enzymes were activated, and a mechanism of non-enzymatic antioxidants was activated; however, it could still cause cellular damage. The observed effect on muscle may be related to the progression of neurodegenerative conditions. In addition, in the brain, these compounds can inactivate the first line of enzymatic antioxidant defense, which is compensated for by the second line, avoiding cellular damage. Ultimately, the gill tissue did not appear to suffer lipid damage, but heme group formation was largely affected by the compounds.


Assuntos
Inseticidas , Piretrinas , Animais , Humanos , Inseticidas/toxicidade , Antioxidantes/metabolismo , Peixe-Zebra/metabolismo , Piretrinas/toxicidade , Estresse Oxidativo , Peroxidação de Lipídeos
8.
Neurotoxicology ; 96: 19-27, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36868382

RESUMO

Pyrethroid-based insecticides are largely used for mosquito control. These compounds have household and agricultural applications with different formulations. Two important compounds used as household insecticides are prallethrin and transfluthrin, both from the pyrethroid chemical group. With the mode of action centered on sodium channels, pyrethroids keep the ionic sodium channels open for a long time causing the death of the insect by nervous hyperexcitability. Given the increased use of household insecticides by humans and the incidence of disease outbreaks with unknown etiology such as autism spectrum disease, schizophrenia, and Parkinson's disease we investigate some physiological inputs of these compounds on zebrafish. In this study, we evaluated the social interaction, shoaling formation, and anxiety-like behavior of zebrafish exposed chronically to transfluthrin- and prallthrin-based insecticides (T-BI and P-BI). In addition, we quantified the activity of the enzyme acetylcholinesterase (AChE) in different brain regions. We observed that both compounds caused anxiolytic behavior and reduced shoaling formation and social interaction. Their behavioral biomarkers indicated a harmful ecological effect on the specie as well as a possible impact of these compounds on autism spectrum disorder (ASD) and schizophrenia (SZP). In addition, the AChE activity would change its activity in different brain regions modulating the anxiety-like behavior and social behavior in zebrafish. We conclude that P-BI and T-BI make us alert about the relationship of these compounds with nervous diseases related to cholinergic signaling.


Assuntos
Transtorno do Espectro Autista , Inseticidas , Piretrinas , Adulto , Animais , Humanos , Inseticidas/toxicidade , Peixe-Zebra/metabolismo , Acetilcolinesterase/metabolismo , Piretrinas/farmacologia , Encéfalo/metabolismo , Colinérgicos , Canais de Sódio
9.
Toxicol Appl Pharmacol ; 461: 116410, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36738974

RESUMO

Different classes of insecticide compounds have been employed to control insects and mosquitoes; Pyrethroids are one of the most common used in both urban and rural household environments. This study investigated the effects of exposure of two doses of commercial transfluthrin-based insecticide (T-BI) on behavior (body bends, pharyngeal pumping rate, and feeding attributes) and biochemical biomarkers (AChE, PolyQ40 aggregations, HSP, antioxidative SOD, CTL, and GST) following three different protocols (transgenerational, neonatal, and lifespan) in Caenorhabditis elegans model system. The relative calculated dose (RCD) and relative calculated half dose (RCHD) of T-BI were compared with those of the control (water). T-BI reduced the health span of worms treated during their whole life and changed biochemical and behavioral patterns due to progenitors' uterine (transgenerational) and neonatal exposures. It was inferred that the effects of T-BI are transgenerational and persistent and can be harmful to non-target species, including humans. In addition, our findings highlight that T-BI contact by progenitors accelerates the establishment of Huntington's disease and causes a cholinergic outbreak in offspring adulthood.


Assuntos
Proteínas de Caenorhabditis elegans , Inseticidas , Animais , Recém-Nascido , Humanos , Adulto , Caenorhabditis elegans , Inseticidas/farmacologia , Proteínas de Caenorhabditis elegans/metabolismo , Ciclopropanos/toxicidade , Ciclopropanos/metabolismo
10.
Environ Toxicol Pharmacol ; 96: 104006, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36328330

RESUMO

The consumption of progestins has increased considerably in recent decades, as has their disposal into the environment. These substances can negatively affect the reproduction, physiology, and behavior of non-target organisms, such as fish. We aimed to evaluate the effects of exposure to environmentally relevant concentrations of levonorgestrel-control birth based (1.3, 13.3, 133, and 1330 ng/L) on the development and behavior of zebrafish (Danio rerio) in terms of mortality, hatching, spontaneous movement, and larval and adult behavioral tests. Exposure caused anxiogenic-like behavior in larvae, which persisted in adults, as demonstrated by the light-dark test. In contrast, it caused anxiolytic-like behavior in the novel tank test. There was a high mortality rate at all tested concentrations and increases in the hormone cortisol at 13.3 ng/L that affected the sex ratio. These changes may lead to an ecological imbalance, emphasizing the risk of early exposure to progestins in the environment.


Assuntos
Poluentes Químicos da Água , Peixe-Zebra , Humanos , Animais , Feminino , Peixe-Zebra/fisiologia , Levanogestrel/toxicidade , Progestinas/toxicidade , Larva , Anticoncepcionais Orais Combinados/farmacologia , Anticoncepção , Poluentes Químicos da Água/toxicidade , Embrião não Mamífero
11.
Environ Pollut ; 314: 120301, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36181934

RESUMO

Household insecticide is largely used for insect and ectoparasite control, in city centers as well as in the countryside. The pyrethroids are the most used class of insecticide, these compounds in low doses have low toxicity for mammalians, in comparison to other compounds, with insecticide effects. The contact of these compounds in sublethal doses begins in early life and many cases, in intrauterine life. Considerable diseases still with undefined etiology, such as neurodegenerative conditions, and Huntington's Disease (HD) is one of them. HD is related to overexpression of Polyglutamine (PolyQ40), its aggregation, and non-solubilization, which leads to neural, behavioral, and cognitive damage. In our study, we evaluate the effect of two sublethal doses of a prallethrin-based insecticide (P-BI), in three different Caenorhabditis elegans life stages transgenerational, neonatal, and lifespan. We evaluated the Body bends and pharyngeal pumping rate, and social feeding as behavioral biomarkers. As well as acetylcholinesterase activity (AChE), PolyQ40 aggregation, antioxidant enzymes, and heat shock protein (HSP) expression. We observe that the toxic effect of P-BI is more pronounced on transgenerational and lifespan exposure. Both sublethal doses of P-BI decreased the AChE activity and retard the HSP expression as well as increased the PolyQ40 aggregates indicating a clear biomarker for possible effect in the progression of the HD, by the environmental contamination.


Assuntos
Doença de Huntington , Inseticidas , Piretrinas , Animais , Humanos , Acetilcolinesterase/metabolismo , Antioxidantes/metabolismo , Caenorhabditis elegans , Proteínas de Choque Térmico , Doença de Huntington/induzido quimicamente , Inseticidas/metabolismo , Mamíferos , Piretrinas/toxicidade
12.
Artigo em Inglês | MEDLINE | ID: mdl-36087705

RESUMO

Highly toxic chemical compounds are present in rivers and lakes, endangering the survival of non-target species. To evaluate the effects of environmental contamination on non-target species, we used the zebrafish as an animal model. Environmental concentrations of the widely used pesticides, glyphosate (GBH) at 4.8 µg·L-1 and 2,4-dichlorophenoxyacetic acid (DBH) at 3.4 µg·L-1, were used. The animals were exposed during the entire period of organogenesis and evaluated in our previous study regarding initial developmental parameters. In the present study, we evaluate these fish when achieve the adult phase, using the novel tank test (NTT) and the aversivity test. In the second step, the animals were allowed to reproduce, and the initial parameters of development, behavioral parameters in the open field test (OFT) and in the aversivity test (AST), and biochemical biomarkers as acetylcholinesterase (AChE), catalase (CAT), and superoxide dismutase (SOD) in the F1 generation were studied. Fish exposed to GBH showed hypermobility, and their anti-predatory reaction was impaired during adulthood, indicating a persistent effect. We also showed that fish had impaired behavioral and survival changes in the F1 generation as well as effects on AChE activity and antioxidant enzymes, characterizing a transgenerational effect. The fish did not show persistent effects in adulthood due to DBH exposure; however, they were unable to reproduce. Our findings demonstrate the serious impact of pesticides on fish, where the effects of contamination can affect future generations and compromise the species' survival.


Assuntos
Resíduos de Praguicidas , Praguicidas , Poluentes Químicos da Água , Ácido 2,4-Diclorofenoxiacético , Acetilcolinesterase , Animais , Antioxidantes , Biomarcadores , Catalase , Resíduos de Praguicidas/toxicidade , Praguicidas/toxicidade , Superóxido Dismutase , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Peixe-Zebra
13.
Environ Toxicol Pharmacol ; 92: 103857, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35342012

RESUMO

Estrogen is considered to be an endocrine disrupter and is becoming increasingly more prevalent in the daily life of humans. In some cases, estrogen is not fully metabolized by organisms and may be excreted in either its original form or in organic complex forms, into water residue systems reaching concentrations of 0.05 ng.L-1 to 75 ng.L-1. However, estrogen 17α-ethinylestradiol (EE2), which is used in oral contraceptives, is very difficult to remove from water. Here, we evaluated whether the synthetic hormone, EE2, affects the nervous system and the behavior of adult zebrafish. We established a range of concentrations (0.05, 0.5, 5, 50, and 75 ng.L-1), in addition to the control, to evaluate the effect of this compound and its bioaccumulation in zebrafish tissues. Here we show that EE2 bioaccumulates in fish and can change its behavior with an increased time in the upper zone (novel tank test) and far from the shoal segment (social preference test), demonstrating a clear anxiolytic pattern. The anxiolytic effect of EE2 can be harmful as it can affect the stress response of the species. The results presented herein reinforce the idea that the presence of EE2 in environmental water can be dangerous for non-target animals.


Assuntos
Poluentes Químicos da Água , Peixe-Zebra , Animais , Biomarcadores/metabolismo , Estrogênios/toxicidade , Etinilestradiol/toxicidade , Água , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/metabolismo
14.
J Food Biochem ; 46(7): e14147, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35347737

RESUMO

The harmful effects of heavy metals on organisms have not been fully described. At present, there is a close relationship between neurodegenerative diseases and copper toxicity. In addition, the copper effect on the central nervous system is followed by high levels of free radicals in different body tissues. An increase in free radical levels leads to aging-related diseases, resulting in the appearance of senile comorbidities. An increase in the consumption of natural compounds that could help to reduce this dangerous effect on organisms was observed. Pitaya (Hylocereus undatus) is a tropical fruit with great antioxidant potential and can help the organism with oxidative damage. This study evaluated the effect of H. undatus on zebrafish organisms in front of copper-induced toxicity. Therefore, the behavior, cholinergic system, antioxidant enzymes, and ALAD activity were evaluated as biomarkers. Our results highlight the great potential of Pitaya's pulp to reduce the levels of anxiety and aggressivity in fish and reduce cortisol levels. It could mediate the normal response of the cholinergic nervous system, antioxidant enzymes, and ALAD activity. Therefore, our data suggest that pitaya might improve the senile aging. PRACTICAL APPLICATIONS: The potential practical application of this study is related to the neuroprotective effect of the Hylocereus undatus microencapsulated pulp extract against metal-induced impairments. The results have shown that this extract is able to reduce the copper-induced damage modulating the antioxidant system and the cholinergic nervous system. One of the implicated potentials of use for this extract is the food supplementation to its fortification.


Assuntos
Antioxidantes , Cactaceae , Animais , Antioxidantes/farmacologia , Colinérgicos , Cobre/toxicidade , Frutas , Extratos Vegetais/farmacologia , Peixe-Zebra/fisiologia
15.
Artigo em Inglês | MEDLINE | ID: mdl-35292329

RESUMO

Pesticides reach water bodies through different routes, either owing to incorrect packaging disposal, direct application to control macrophytes, leaching from fields, or natural degradation processes. In the aquatic environment, adverse effects in non-target species that come in contact with these substances are poorly understood. Currently, the most used pesticides are glyphosate (GBH) and 2,4-dichlorophenoxyacetic acid-based herbicides (DBH), as its presence in water bodies is already known, we used environmental concentrations and our exposure time comprised the entire period of organogenesis (3-120 h post-fertilization). We evaluated the response of embryos in their early development with the parameters of mortality, hatching, spontaneous movement, and heart rate; and it's through behavior the open field test and aversive stimulus, as well as biochemical analyzes of acetylcholinesterase activity (AChE), catalase (CTL) and superoxide dismutase (SOD) as a possible mechanism of action. Exposure to GBH decreased survival, caused hypermobility and anxiolytic behavior, negatively affected the anti-predatory behavior of the larvae, and increases acetylcholinesterase activity, whereas exposure to DBH caused only slight hypermobility in the larvae and increases acetylcholinesterase activity. These changes may compromise the perpetuation of the species, the search for partners/food, and facilitate the action of predators, which can result in serious ecological consequences.


Assuntos
Herbicidas , Praguicidas , Poluentes Químicos da Água , Acetilcolinesterase/metabolismo , Animais , Herbicidas/toxicidade , Larva , Praguicidas/toxicidade , Água , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/metabolismo
16.
Artigo em Inglês | MEDLINE | ID: mdl-33772638

RESUMO

The dopaminergic system of zebrafish is complex and the numerous pathways and receptors in the central nervous system (CNS) are being extensively studied. A critical factor for the synthesis, activation and release of catecholamines (CAs) is the presence of tyrosine hydroxylase, an enzyme which converts L-tyrosine into levodopa. Levodopa thus is the intermediary in the synthesis of dopamine (DA) and norepinephrine (NE) and promotes its release; therefore, CAs play an important role in the CNS with hormonal functions. Here, we use levodopa/carbidopa to clarify the involvement of the dopaminergic pathway in the stress response in zebrafish submitted to an acute stress challenge. Acute stress was induced by chasing fish with a net for 2 min and assessed by measuring whole-body cortisol levels. Two experiments were carried out, the first with exposure to levodopa/carbidopa and the second with exposure to AMPT and levodopa/carbidopa. Levodopa/carbidopa balances the stress response through its action on the zebrafish hypothalamic-pituitary-adrenal (HPA) axis. Changes in cortisol levels suggest that DA was related to the balance of the stress response and that NE decreased this response. These effects were specific to stress since levodopa/carbidopa did not induce changes in cortisol in non-stressed fish.


Assuntos
Glândulas Suprarrenais/efeitos dos fármacos , Carbidopa/farmacologia , Agonistas de Dopamina/farmacologia , Dopamina/metabolismo , Neurônios Dopaminérgicos/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Levodopa/farmacologia , Estresse Fisiológico , Peixe-Zebra/metabolismo , Glândulas Suprarrenais/metabolismo , Animais , Neurônios Dopaminérgicos/metabolismo , Combinação de Medicamentos , Inibidores Enzimáticos/farmacologia , Feminino , Hidrocortisona/metabolismo , Sistema Hipotálamo-Hipofisário/metabolismo , Masculino , Tirosina 3-Mono-Oxigenase/antagonistas & inibidores , Tirosina 3-Mono-Oxigenase/metabolismo , Proteínas de Peixe-Zebra/antagonistas & inibidores , Proteínas de Peixe-Zebra/metabolismo , alfa-Metiltirosina/farmacologia
17.
Behav Brain Res ; 404: 113169, 2021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33577884

RESUMO

The zebrafish (Danio rerio) is widely used as a promising translational model organism for studying various brain disorders. Zebrafish are also commonly used in behavioral and drug screening assays utilizing individually tested (socially isolated) fish. Various sounds represent important exogenous factors that may affect fish behavior. Mounting evidence shows that musical/auditory environmental enrichment can improve welfare of laboratory animals, including fishes. Here, we show that auditory environmental enrichment mitigates anxiogenic-like effects caused by acute 24-h social isolation in adult zebrafish. Thus, auditory environmental enrichment may offer an inexpensive, feasible and simple tool to improve welfare of zebrafish stocks in laboratory facilities, reduce unwanted procedural stress, lower non-specific behavioral variance and, hence, collectively improve zebrafish data reliability and reproducibility.


Assuntos
Estimulação Acústica/psicologia , Ansiedade/prevenção & controle , Hidrocortisona/sangue , Isolamento Social , Animais , Ansiedade/etiologia , Ansiedade/psicologia , Meio Ambiente , Feminino , Hidrocortisona/fisiologia , Masculino , Música , Isolamento Social/psicologia , Peixe-Zebra
18.
Stress ; 24(1): 107-112, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32013653

RESUMO

We report the effects of acute and chronic stress on the expression of selective immune-related genes and markers of neuronal function in the brain of the zebrafish (Danio rerio). Fish were distributed into three groups: the non-stressed control group; the acute stress (AS) group, submitted to a single stressing episode; and the unpredictable chronic stress (UCS) group, submitted to two daily stressing episodes of alternating times and types of stress. The stressing protocols were applied for a period of 14 days. The UCS protocol triggered the expression of the pro-inflammatory cytokine genes IL-1ß and TNF-α, the anti-inflammatory cytokine IL-10 (negative feedback from the immune system), reduction in cFOS gene expression, and caused neuro-inflammation. The AS protocol had no effect on gene expression. Altered expression of cytokine genes, as observed in our study, correlates with several pathologies associated with neuro-inflammation, and the reduction of cFOS gene expression may indicate the occurrence of reduced neuronal plasticity. Our study further extends our knowledge about the interaction of the immune system and the different forms of stress.


Assuntos
Citocinas , Peixe-Zebra , Animais , Encéfalo/metabolismo , Citocinas/genética , Citocinas/metabolismo , Neurônios/metabolismo , Estresse Psicológico/genética , Peixe-Zebra/genética , Peixe-Zebra/metabolismo
19.
Sci Total Environ ; 757: 143794, 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33272603

RESUMO

Viticulture plays an important role in generating income for small farms globally. Historically, vineyards use large quantities of phytosanitary products, such as Bordeaux mixture [Ca(OH)2 + CuSO4], to control plant diseases. These products result in the accumulation of copper (Cu) in the soil and increases the risk of transfer to water bodies. Thus, it is important to evaluate whether the presence of Cu-bearing particles in water is toxic to aquatic fauna. This study conducted chemical, mineralogical, and particle size evaluations on water samples and sediments collected from a watershed predominantly cultivated with old vineyards. The proportion of Cu-rich nanoparticles (<10 nm) in the sediment was ~27%. We exposed zebrafish to different dilutions of water and sediment samples that collected directly from the study site (downstream river) under laboratory conditions. Then, we evaluated their exploratory behavior and the stress-related endocrine parameter, whole-body cortisol. We also carried out two experiments in which zebrafish were exposed to Cu. First, we determined the median lethal concentration (LC50-96 h) of Cu and then assessed whether Cu exposure results in effects similar to those associated with exposure to the water and sediment samples collected from the study site. The water and sediment samples directly impacted the exploratory behavior of zebrafish, showing clear anxiety-like behavioral phenotype and stress in terms of cortisol increase (during the second rain event). The Cu exposure did not mimic the same behavioral changes triggered by the water and sediment samples, although it had caused similar stress in the fish. Our results highlight that even at low concentrations, the water and sediment samples from vineyard watershed runoff were able to induce behavioral and endocrine changes that may harm the ecological balance of an aquatic environment.


Assuntos
Poluentes Químicos da Água , Água , Animais , Fazendas , Sedimentos Geológicos , Rios , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Peixe-Zebra
20.
Artigo em Inglês | MEDLINE | ID: mdl-32800866

RESUMO

Methylphenidate (MPH) is a psychostimulant widely misused to increase wakefulness by drivers and students. Also, MPH can be found in dietary supplements in a clandestine manner aiming to burst performance of physical exercise practitioners. The abusive use of high doses of caffeine (CAF) in these contexts is equally already known. Here, we demonstrate the behavioral, oxidative and mitochondrial effects after acute exposure to high doses of MPH (80 mg/L) and CAF (150 mg/L), alone or associated (80 mg/L + 150 mg/L, respectively). We used zebrafish as animal model due to its high translational relevance. We evaluated the behavioral effects using the Novel Tank Test (NTT), Social Preference Test (SPT) and Y-maze Task and analyzed biomarkers of oxidative stress and activity of mitochondrial respiratory chain complexes. MPH alone induced antisocial behavior. MPH inhibited lipid peroxidation. The association of MPH + CAF presented memory impairment and anxiogenic behavior. In oxidative status, it inhibited lipid peroxidation, increased protein carbonylation and mitochondrial complex II, III and IV activity. Our results demonstrate that MPH and CAF alone negatively impact the typical behavioral of zebrafish. When associated, changes in cognition, memory, oxidative and mitochondrial status are more relevant.


Assuntos
Cafeína/toxicidade , Disfunção Cognitiva/metabolismo , Transtornos da Memória/metabolismo , Metilfenidato/toxicidade , Mitocôndrias/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Animais , Cafeína/administração & dosagem , Estimulantes do Sistema Nervoso Central/administração & dosagem , Estimulantes do Sistema Nervoso Central/toxicidade , Cognição/efeitos dos fármacos , Cognição/fisiologia , Disfunção Cognitiva/induzido quimicamente , Feminino , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Transtornos da Memória/induzido quimicamente , Metilfenidato/administração & dosagem , Estresse Oxidativo/fisiologia , Peixe-Zebra
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...