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1.
Environ Sci Pollut Res Int ; 31(43): 55301-55316, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39225930

RESUMO

In this study, neodymium-doped titanium dioxide (Nd-TiO2) nanoparticles were synthesized via a hydrothermal method for the photocatalytic degradation of Rhodamine B (RhB) under UV and sunlight conditions. The properties of these NPs were comprehensively characterized. And optimization of RhB degradation was conducted using control-variable experiment and artificial neural networks (ANN) under various operational conditions and in the presence of competing compounds. The acute toxicity of both NPs, RhB, and the environmental impact of the photocatalytic treatment effluent on Danio rerio were evaluated. The Nd modification increased the catalyst's specific surface area and thermal stability. X-ray diffraction confirmed the tetragonal anatase phase in undoped TiO2, while Nd-doped TiO2 exhibited shifts in peaks and the presence of brookite and rutile phases. Nd (1 mol%) doped TiO2 demonstrated superior RhB photocatalytic degradation efficiency, achieving 95% degradation and 82% total organic carbon (TOC) removal within 60 min under UV irradiation. Optimization under sunlight conditions yielded 95.14% RhB removal with 0.28 g/L photocatalyst and 1% doping. Under UV light, 98.12% RhB removal was optimized with 0.97% doping, along with the presence of humic acid and CaCl2. ANN modeling achieved high precision (R2 of 0.99) in modeling environmental photocatalysis. Toxicity assessments indicated that the 96-h LC50 values were 681.59 mg L-1 for both NPs, and 23.02 mg L-1 for RhB. The treated dye solution exhibited a significant decline in toxicity, emphasizing the potential of 1% Nd-TiO2 in wastewater treatment.


Assuntos
Neodímio , Rodaminas , Titânio , Titânio/química , Titânio/toxicidade , Rodaminas/química , Neodímio/química , Catálise , Animais , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade , Peixe-Zebra , Raios Ultravioleta
2.
J Fish Biol ; 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39267308

RESUMO

The use of different mazes to assess spatial learning has become more common in fish behavior studies in recent decades. This increase in fish cognition research has opened the door to numerous possibilities for exciting and diverse questions, such as identifying ecological drivers of spatial cognition and understanding the role individual variation plays in navigational abilities. There are many different types of mazes, each with its own specific considerations, making it challenging to determine exactly which spatial test is the most relevant and appropriate for a particular experiment. Many spatial mazes, such as the T-maze and Y-maze, have been successfully adapted from rodent studies, particularly with respect to zebrafish, a widely accepted non-mammalian model in biomedical studies. Standardization across studies is increasing with these easily accessible maze designs, validating them for use in fish; however, variations in design (e.g., length of arms and scale) and procedure still exist, and the impact of these variations on results is largely unknown. The efforts to standardize mazes outside zebrafish work are also more limited. Other mazes have been developed specifically for use on fish, with design modifications varying widely, making it difficult to draw comparisons. In this review, we have highlighted the many design and procedural elements that should be considered for the acquisition of reliable behavioral data, with the goal of drawing readers' attention to aspects of experimentation that are often not given the careful consideration that they deserve. We then argue that additional focused research and reporting is needed to produce more reliable methods in spatial learning research across a broader range of subjects.

3.
J Fish Biol ; 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39319507

RESUMO

Fish schooling has attracted the interest of the scientific community for centuries. Energy savings have been long posited to be a key determinant for the emergence of schooling patterns. Yet, current methodologies do not allow the precise quantification of the metabolic rate of specific individuals within the school, typically leaving researchers with only a single, global measurement of metabolic rate for the collective. In this paper, we demonstrate the feasibility of inferring metabolic rate of swimming fish using the mouth-opening frequency, a simple proxy that can be scored utilizing video recordings in the laboratory or in the field, even for small fish. The mouth-opening frequency is independent of hydrodynamic interactions within the school, thereby mitigating potential confounding factors that arise when using locomotory measures associated with tail-beat motion. We assessed the reliability of mouth-opening frequency as a proxy for metabolic rate by conducting experiments on zebrafish (Danio rerio) using swimming respirometry. We varied the flow speed from 0.8 to 3.2 body lengths per second and extracted tail-beat motion and mouth opening from video recordings. Our results revealed a strong correlation between oxygen uptake and mouth-opening frequency for nonzero flow speeds but not in quiescent water. Contrary to our expectations, we did not find evidence in favor of the use of tail-beat frequency as a proxy for metabolic rate. Overall, our results open the door to the study of individual metabolic rates in fish schools without confounding factors related to hydrodynamic interactions.

4.
Toxicol Appl Pharmacol ; 492: 117107, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39288838

RESUMO

To investigate the difference in the development and neurobehavior between aluminum chloride (AlCl3) and nano-alumina (AlNPs) in adult zebrafish and the role of triggering receptor expressed on myeloid cells (TREM2) in this process. Zebrafish embryos were randomly administered with control, negative control, TREM2 knockdown, AlCl3, TREM2 knockdown + AlCl3, AlNPs, and TREM2 knockdown + AlNPs, wherein AlCl3 and AlNPs were 50 mg/L and TREM2 knockdown was achieved by microinjecting lentiviral-containing TREM2 inhibitors into the yolk sac. We assessed development, neurobehavior, histopathology, ultrastructural structure, neurotransmitters (AChE, DA), SOD, genes of TREM2 and neurodevelopment (α1-tubulin, syn2a, mbp), and AD-related proteins and genes. AlCl3 significantly lowered the malformation rate than AlNPs, and further increased rates of malformation and mortality following TREM2 knockdown. The locomotor ability, learning and memory were similar between AlCl3 and AlNPs. TREM2 deficiency further exacerbated their impairment in panic reflex, microglia decrease, and nerve fibers thickening and tangling. AlCl3, rather than AlNPs, significantly elevated AChE activity and p-tau content while decreasing TREM2 and syn2a levels than the control. TREM2 loss further aggravated impairment in the AChE and SOD activity, and psen1 and p-tau levels. Therefore, AlCl3 induces greater developmental toxicity but equivalent neurobehavior toxicity than AlNPs, while their toxicity was intensified by TREM2 deficiency.

5.
Artigo em Inglês | MEDLINE | ID: mdl-39298017

RESUMO

New methods are essential to characterize the performance of substitute procedures for detecting therapeutic action(s) of a chemical or key signal of toxicological events. Herein, it was discussed the applications and advantages of using arthropods, worms, and fishes in pharmacological and/or toxicology assessments. First of all, the illusion of similarity covers many differences between humans and mice, remarkably about liver injury and metabolism of xenobiotics. Using invertebrates, especially earthworms (Eisenia fetida), brine shrimps (Artemia salina, Daphnia magna), and insects (Drosophila melanogaster) and vertebrates as small fishes (Oryzias latipes, Pimephales promelas, Danio rerio) has countless advantages, including fewer ethical conflicts, short life cycle, high reproduction rate, simpler to handle, and less complex anatomy. They can be used to find contaminants in organic matters and water and are easier genetically engineered with orthologous-mutated genes to explore specific proteins involved in proliferative and hormonal disturbances, chemotherapy multidrug resistance, and carcinogenicity. As multicellular embryos, larvae, and mature organisms, they can be tested in bigger-sized replication platforms with 24-, 96-, or 384-multiwell plates as cheaper and faster ways to select hit compounds from drug-like libraries to predict acute, subacute or chronic toxicity, pharmacokinetics, and efficacy parameters of pharmaceutical, cosmetic, and personal care products. Meanwhile, sublethal exposures are designed to identify changes in reproduction, body weight, DNA damages, oxidation, and immune defense responses in earthworms and zebrafishes, and swimming behaviors in A. salina and D. rerio. Behavioral parameters also give specificities on sublethal effects that would not be detected in zebrafishes by OECD protocols.

6.
Biol Futur ; 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39278890

RESUMO

This study aimed to screen 10 medicinal plant extracts on zebrafish (Danio rerio), evaluating their impact on the complement system, immunoglobulin M (IgM) levels, lysozyme, and peroxidase activity, while also enhancing their efficacy through the gradual release using alginate-chitosan nanocapsules. The prepared methanolic extracts were combined with fish feed. The fish were divided into 12 groups, including 10 treatment groups, a positive and a negative control group. Results showed varying impacts of the extracts on the immune and antioxidant systems, with Cinnamon (Cinnamon cassia) and Hypericum (Hypericum perforatum) extracts demonstrating the most significant effects. Subsequently, Cinnamon and Hypericum extract were encapsulated in alginate-chitosan nanocapsules to assess their impact on zebrafish immune parameters, separately and synergistically. Gradual release of the extracts from the nanocapsules was observed, with slower release at pH 2 compared to pH 7. Overall, Cinnamon and Hypericum extracts exhibited substantial immune system enhancement, and their encapsulation in nanocapsules improved their effects on zebrafish immune parameters. These findings suggest using these encapsulated extracts to enhance immune responses in aquatic organisms.

7.
Artigo em Inglês | MEDLINE | ID: mdl-39276852

RESUMO

Evidence suggests that fish are more tolerant than mammals to imbalanced dietary amino acid profiles. However, the behavioral and physiological responses of fish to individual deficiencies in dietary indispensable amino acids (IDAA) remain unclear. This study examined how stomachless fish respond to diets deficient in limiting IDAA (lysine, methionine, and threonine), using Zebrafish (Danio rerio) as a model. The response to deficient diets was assessed based on; 1) growth performance and feeding efficiency; 2) feed intake; 3) expression of appetite-regulating hormones and nutrient-sensing receptors; and 4) muscle postprandial free amino acid (FAA) levels. There were 6 treatments, each with 3 replicate tanks. A semi-purified diet was formulated for each group. The CG diet was based on casein and gelatin, while the FAA50 diet had 50 % of dietary protein supplied with crystalline amino acids. Both were formulated to contain matching, balanced amino acid profiles. The remaining diets were formulated the same as the FAA50 diet, with minor adjustments to create deficiencies in selected IDAA. The (-) Lys, (-) Met, and (-) Thr diets had lysine, methionine, and threonine withheld from the FAA mix, respectively, and the Def diet was deficient in all three. The juvenile Zebrafish were fed to satiation 3 times daily from 21 to 50 days-post-hatch. Results showed that 50 % replacement of dietary protein with crystalline amino acids significantly reduced growth of juvenile Zebrafish. There were no significant differences in growth between the FAA50 group and groups that received deficient diets. The deficiency of singular IDAA did not induce significant changes in feed intake; however, the combined deficiency in the Def diet caused a significant increase in feed intake. This increased feed intake led to decreased feeding efficiency. A significant decrease in feeding efficiency was also observed in the (-) Lys group. There was an observed upregulation of neuropeptide Y (NPY), an orexigenic hormone, in the Def group. Overall, results from this study suggest stomachless fish increase feed intake when challenged with IDAA-deficient diets, and the regulation of NPY might play a role in this response.

8.
Artigo em Inglês | MEDLINE | ID: mdl-39260617

RESUMO

Low-temperature stress poses a significant risk to the survival of both cultivated and wild fish populations. Existing studies have found that the pre-acclimation of fishes to moderate cold stress can stimulate the activation of acclimation pathways, thereby enhancing their tolerance to cold stress. The fitness of fish relies heavily on appropriately controlled transcriptional reactions to environmental changes. Despite previous characterization of gene expression profiles in various fish species during cold acclimation, the specific genes responsible for essential functions in this process remain largely unknown, particularly the down-regulated genes induced by cold acclimation. To investigate the genes involved in cold acclimation, this study employed real-time quantitative PCR (RT-qPCR), molecular cloning, microinjection techniques, and cold stress experiments to determine the genes that play an essential part in cold acclimation. Consequently, 18 genes were discovered to be down-regulated in larval zebrafish experiencing cold stress. All 18 genes successfully detected overexpression in zebrafish at 96 and 126 hpf (fold change ≥3), which declined with the growth of zebrafish. Following microinjection, it was observed that her8a, cyp51, lss, txnipb, and bhlha9 had an adverse impact on the survival rate of zebrafish larvae under cold stress. These genes have been identified to play significant roles in various biological processes. For instance, bhlha9 has been found to be involved in both limb development and temperature sensing and her8a has been implicated in neural development. Additionally, cyp51 and lss have been identified as participants in the cholesterol synthesis pathway. Txnipb has been reported to induce cell apoptosis, thereby potentially influencing the survival rate of zebrafish larvae under cold stress. These findings offered crucial data for the analysis of molecular processes related to cold tolerance and the development of cold-resistant fish breeding.

9.
Molecules ; 29(17)2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39274923

RESUMO

The present study explores the synthesis and bio-safety evaluation of gadolinium-doped carbon quantum dots (GCQDs) as a potential dual-contrast agent for diagnostic imaging. GCQDs exhibit both fluorescent and magnetic properties, making them suitable for UV-Vis and magnetic resonance imaging (MRI). The synthesis of GCQDs was achieved via hydrothermal treatment, incorporating gadolinium into the carbon quantum dot matrix. The magnetic properties of GCQDs were analyzed, showing significantly enhanced values compared to gadobutrol, a common MRI contrast agent. However, synthesis constraints limit the gadolinium content achievable in nanodots. To assess the safety of GCQDs, their effects on the embryonic development of zebrafish (Danio rerio) were examined. Various concentrations of GCQDs were tested, observing mortality rates, hatchability, malformations, heartbeats, spontaneous movement, and GCQDs uptake. Dialysis studies indicated that gadolinium ions are incorporated into the internal structure of the carbon nanodots. Zebrafish toxicity tests revealed that while survival rates were comparable to control groups, hatchability decreased significantly with higher gadolinium concentrations in GCQDs. Fluorescence microscopy showed no statistical differences in the fluorescence intensity between groups. These findings suggest that GCQDs could serve as an effective dual-contrast agent, combining the optical imaging capabilities of CQDs with the enhanced MRI contrast provided by gadolinium. This study underscores the need for further research on the synthesis methods and biological interactions of GCQDs to ensure their safety and efficacy in medical applications.


Assuntos
Carbono , Meios de Contraste , Gadolínio , Imageamento por Ressonância Magnética , Pontos Quânticos , Peixe-Zebra , Pontos Quânticos/química , Pontos Quânticos/toxicidade , Gadolínio/química , Meios de Contraste/química , Meios de Contraste/síntese química , Animais , Peixe-Zebra/embriologia , Carbono/química , Imageamento por Ressonância Magnética/métodos , Diagnóstico por Imagem/métodos
10.
Aquat Toxicol ; 276: 107086, 2024 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-39277994

RESUMO

The study aims to investigate the effects of nano-alumina (AlNPs) on the early development and neurobehavior of zebrafish and the role of mTOR in this process. After embryos and grown-up larvae exposed to AlNPs from 0 to 200 µg/mL, we examined the development, neurobehavior, AlNPs content, and mTOR pathway genes. Moreover, embryos were randomly administered with control, negative control, mTOR knockdown, AlNPs, and mTOR knockdown + AlNPs, then examined for development, neurobehavior, oxidative stress, neurotransmitters, and development genes. As AlNPs increased, swimming speed and distance initially increased and then decreased; thigmotaxis and panic-avoidance reflex substantially decreased in the high-dose AlNPs group; aluminum and nanoparticles considerably accumulated in the 100 µg/mL AlNPs group; AlNPs at high dose decreased mTOR gene and protein levels, stimulating autophagy via increasing ULK1 and ULK2. mTOR knockdown exacerbated the harm to normal development rate, eye and body length, and neurobehavior induced by AlNPs through raising ROS, SOD, and ACH levels but decreasing AchE activity and development genes. Therefore, AlNPs suppress neurobehavior through downregulating mTOR, and mTOR knockdown further aggravates their early development and neurobehavior loss, suggesting mTOR could be a potential target for the toxicity of AlNPs.

11.
Toxicology ; 508: 153927, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39151607

RESUMO

There is an increasing incidence and prevalence of fatty liver disease in the western world, with steatosis as the most prevalent variant. Known causes of steatosis include exposure to food-borne chemicals, and overconsumption of alcohol, carbohydrates and fat, and it is a well-known side effect of certain pharmaceuticals such as tetracycline, amiodarone and tamoxifen (drug-induced hepatic steatosis). Mechanistic knowledge on chemical-induced steatosis has greatly evolved and has been organized into adverse outcome pathways (AOPs) describing the chain of events from first molecular interaction of a substance with a biological system to the adverse outcome, intrahepatic lipid accumulation. In this study, three known steatosis-inducing pesticides (imazalil, clothianidin, and thiacloprid) were tested for their ability to induce hepatic triglyceride accumulation in the zebrafish (Danio rerio) embryo (ZFE) at 5 days post fertilization, both as single compounds and equipotent binary mixtures. The results indicate that the ZFE is very well applicable as a higher tier testing model to confirm effects in downstream key events in AOPs, that is, chemically-induced triglyceride accumulation in the whole organism and production of visible steatosis. Moreover, dose addition could be concluded for binary mixtures of substances with similar and with dissimilar modes of action.


Assuntos
Embrião não Mamífero , Fígado Gorduroso , Praguicidas , Triglicerídeos , Peixe-Zebra , Animais , Fígado Gorduroso/induzido quimicamente , Embrião não Mamífero/efeitos dos fármacos , Triglicerídeos/metabolismo , Praguicidas/toxicidade , Modelos Animais de Doenças , Relação Dose-Resposta a Droga
12.
Chemosphere ; 364: 143012, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39103101

RESUMO

Due to its extensive use as a painkiller, anti-inflammatory, and immune modulatory agent, as well as its effectiveness in treating severe COVID-19, dexamethasone, a synthetic glucocorticoid, has gained attention not only for its impact on public health but also for its environmental implications. Various studies have reported its presence in aquatic environments, including urban waters, surface samples, sediments, drinking water, and wastewater effluents. However, limited information is available regarding its toxic effects on nontarget aquatic organisms. Therefore, this study aimed to investigate the mechanism of toxicity underlying dexamethasone-induced brain damage in the bioindicator Danio rerio following long-term exposure. Adult zebrafish were treated with environmentally relevant concentrations of dexamethasone (20, 40, and 60 ng L-1) for 28 days. To elucidate the possible mechanisms involved in the toxicity of the pharmaceutical compound, we conducted a behavioral test battery (Novel Tank and Light and Dark tests), oxidative stress biomarkers, acetylcholinesterase enzyme activity quantification, histopathological analysis, and gene expression analysis using qRT-PCR (p53, bcl-2, bax, caspase-3, nrf1, and nrf2).The results revealed that the pharmaceutical compound could produce anxiety-like symptoms, increase the oxidative-induced stress response, decrease the activity of acetylcholinesterase enzyme, and cause histopathological alterations, including perineuronal vacuolization, granular and molecular layers deterioration, cell swallowing and intracellular spaces. The expression of genes involved in the apoptotic process (p53, bax, and casp-3) and antioxidant defense (nrf1 and nrf2) was upregulated in response to oxidative damage, while the expression of the anti-apoptotic gene bcl-2 was down-regulated indicating that the environmental presence of dexamethasone may pose a threat to wildlife and human health.


Assuntos
Apoptose , Dexametasona , Estresse Oxidativo , Poluentes Químicos da Água , Peixe-Zebra , Animais , Estresse Oxidativo/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Dexametasona/toxicidade , Poluentes Químicos da Água/toxicidade , Glucocorticoides/toxicidade , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Lesões Encefálicas/induzido quimicamente
13.
Sci Total Environ ; 951: 175555, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-39168327

RESUMO

Facial masks are a source of plastic microfibres (PMFs) in the aquatic environment, an emerging risk factor for aquatic organisms. However, little is known concerning its impact during the early developmental stages of fish. Thus, the current study aimed to evaluate the potential interaction and developmental toxicity of PMFs derived from leachate of surgical masks (SC-Msk) and N-95 facial masks (N95-Msk) using a multi-biomarker approach in developing zebrafish (Danio rerio). PMFs from both facial masks were obtained and characterized by multiple techniques. Zebrafish embryos were exposed to environmentally relevant concentrations of PMFs from both facial masks (1000, 10,000, and 100,000 particle L-1), and the toxicity was analysed in terms of mortality, hatching rate, neurotoxicity, cardiotoxicity, morphological changes, reactive oxygen species (ROS) levels, cell viability, and behavioural impairments. The results showed that both facial masks can release PMFs, but the N95-Msk produced a higher concentration of PMFs than SC-Msk. Both PMFs can interact with zebrafish chorion and don't cause effects on embryo mortality and hatching; however, zebrafish embryos showed cardiotoxic effects, and larvae showed increased agitation, average speed, and distance travelled, indicating the behavioural impairments induced by PMFs derived from facial masks. Overall, results showed the risk of PMFs to the health of freshwater fish, indicating the need for greater attention to the disposal and ecotoxicological effects of facial masks on aquatic organisms.


Assuntos
Plásticos , Poluentes Químicos da Água , Peixe-Zebra , Animais , Poluentes Químicos da Água/toxicidade , Plásticos/toxicidade , Máscaras , Embrião não Mamífero/efeitos dos fármacos
14.
Sci Rep ; 14(1): 19328, 2024 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-39164319

RESUMO

Environmental pollutants used as plasticizers in food packaging and in thousands of everyday products have become harmful for their impact on human health. Among them, phthalates, recognized as emerging endocrine disruptors (EDs) can induce toxic effects leading to different health disorders. Only few studies evaluated the effects of di-n-hexyl phthalate (DnHP) in in vivo models and no studies have been conducted to investigate the effect of DnHP on the endocannabinoid system (ECS), one of the majors signaling pathways involved in the microbiota-gut-brain axis. Due to the current relevance of probiotic bacteria as beneficial dietary interventions, the present study was aimed at evaluating the potential neuroprotective impact of daily administration of Lactiplantibacillus (Lpb.) plantarum IMC513 on zebrafish adults exposed to DnHP, with a focus on ECS modulation. Gene expression analysis revealed a promising protective role of probiotic through the restoration of ECS genes expression to the control level, in the brain of zebrafish daily exposed to DnHP. In addition, the levels of main endocannabinoids were also modulated. These findings confirm the potential ability of probiotics to interact at central level by modulating the ECS, suggesting the use of probiotics as innovative dietary strategy to counteract alterations by EDs exposure.


Assuntos
Endocanabinoides , Probióticos , Peixe-Zebra , Animais , Probióticos/administração & dosagem , Probióticos/farmacologia , Endocanabinoides/metabolismo , Ácidos Ftálicos/toxicidade , Encéfalo/metabolismo , Encéfalo/efeitos dos fármacos
15.
Chem Biodivers ; : e202401207, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39088251

RESUMO

Anxiety and epilepsy are common worldwide and represent a primary global health concern. Fisetin, a flavonoid isolated from Bauhinia pentandra, has a wide range of biological activities may be a promising alternative to combat diseases related to the central nervous system (CNS). The present study aimed to investigate the anxiolytic and anticonvulsant effects of fisetin on adult zebrafish. Furthermore, molecular docking simulations were performed to improve the results. Fisetin did not present toxicity and caused anxiolytic behavior and delayed seizures in animals. This effect may occur through serotonin neurotransmission at 5-HT3A and/or 5-HT3B receptors. Molecular docking simulations showed that fisetin interacts with the orthosteric site of the 5-HT3A receptor with strong H-bond interactions with the Trp156 residue, with a strong contribution from the catechol ring, a behavior similar to that of the antagonist co-crystallized inhibitor granisetron (CWB). Fisetin may be a promising alternative to combat diseases related to the central nervous system. Keywords anxiety • Bauhinia pentandra • Danio rerio • epilepsy • fisetin.

16.
Artigo em Inglês | MEDLINE | ID: mdl-39173811

RESUMO

Antimony (Sb) and its compounds can be harmful to people and are known to cause cancer, so they are a key pollutant to control. This study investigated the influence of antimony on non-enzymatic antioxidants and the blood-brain barrier (BBB) in zebrafish(Danio rerio), a model organism that shares a high degree of genetic similarity with humans. Zebrafish were exposed to different doses of antimony in water for 7, 18, and 30 days. The results indicated that antimony accumulated most in the liver, followed by the gills, flesh, and brain, with the accumulation increasing as the exposure duration extends. Additionally, under identical antimony concentrations, the buildup in the four tissues was positively correlated with the duration of exposure. After 18 days of exposure, the total antioxidant capacity (T-AOC) and endogenous non-enzymatic antioxidants vitamin C (VC) and vitamin E (VE) decreased as a result of antimony ingestion in zebrafish, although cysteine secretion was increased in the liver, gills, and brain. The structural integrity of the BBB was compromised by the elevation of ApoE4 and MMP-9 levels as a result of antimony exposure, which led to the breakdown of the basal lamina, tight junctions, and nerve fibers in the brain. At this injured region, 5-HT and MBP were also able to easily enter and leave the BBB, albeit at variable rates. Additionally, when the antimony exposure level reached 16.58 mg·L-1, antimony penetrated the BBB and bound to erythrocytes, causing their lysis.


Assuntos
Antimônio , Antioxidantes , Barreira Hematoencefálica , Poluentes Químicos da Água , Peixe-Zebra , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Antimônio/toxicidade , Antioxidantes/metabolismo , Poluentes Químicos da Água/toxicidade , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Brânquias/ultraestrutura , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Estresse Oxidativo/efeitos dos fármacos
17.
Behav Brain Res ; 473: 115179, 2024 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-39103124

RESUMO

Glucocorticoids (GCs) have a wide spectrum of effects on animal behavior. A recently suggested effect involves determining the structure of individual differences, that is how the behavioral traits of an individual covary, forming the so-called behavioral syndromes. As GCs can exert their action in multiple ways, e.g., via rapid non-genomic effects or via the activation of two highly homologous members of the steroid receptor family acting as transcription factors, it is unclear how the GC modulation of behavioral syndromes takes place. We exploited a zebrafish line with a frameshift mutation in the gene encoding the GC receptor (Gr), to investigate this question. We found that lack of Gr altered the average score of several behavioral traits in the mutant line, determining reduced boldness, and increased activity and sociability. Critically, the pattern of covariation between these traits was also substantially affected by the loss of Gr. The most evident effect was an association of traits involved in boldness in the gr mutant line. This study reveals that, in zebrafish, Gr is not only involved in the modulation of the average value of behavioral traits, but also in how the behavioral traits of an individual are interrelated and determine the behavioral syndromes.


Assuntos
Comportamento Animal , Receptores de Glucocorticoides , Peixe-Zebra , Animais , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo , Comportamento Animal/fisiologia , Mutação da Fase de Leitura , Masculino , Animais Geneticamente Modificados , Comportamento Social , Feminino , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
18.
Fish Physiol Biochem ; 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39105975

RESUMO

This study evaluates using different levels of the white button mushroom powder (WBMP) on some mucosal innate immune parameters (lysozyme, protease, esterase, alkaline phosphatase activities, and total immunoglobulin levels), and the relative expression of some principal immune-relevant genes (lysozyme, TNF-α, and IL-1ß) in the zebra danio intestine. Zebrafish specimens (1.75 ± 0.25 g) were divided into experimental units based on the additives to a diet including 5, 10, and 20 g of WBMP per kilogram of food weight, alone or in conjunction with the antibiotic (10 mg/kg BW), and the AGRIMOS (1 g/kg food weight). Following the 11-day experimental duration, the skin mucus and intestine were sampled. To assess the immune gene expression, the real-time PCR detection system was conducted according to the ΔΔCt method using the IQ5 software (Bio-RAD). Results showed that all groups had a significant increase in terms of mucosal lysozyme activity compared to the control group. Examination of total immunoglobulin, protease, esterase, and ALP activity in fish under experimental treatment showed that there was no significant difference between the trial groups and the control groups. The most expression of the lysozyme gene was related to the group that was separately taken the lower concentration (5 g per kg of FW) of WBMP. In conclusion, the amount of 1% mushroom powder in the diet can improve its immune function. Our recommendation is that given the positive effects that mushroom powder added on the diet alone, avoid taking antibiotics for this purpose.

19.
Curr Res Toxicol ; 7: 100187, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39104612

RESUMO

To study the effects of drugs on embryo/fetal development (EFD), developmental and reproductive toxicity studies in zebrafish (Danio rerio) embryos is expected to be an accepted alternative method to animal studies using mammals. However, there is a lack of clarity in the relationship between the concentration of developmental toxicity agents in whole embryos or larvae (Ce) and that in aqueous solution (Cw), and also between the amount of drug exposure required to cause developmental toxicity in zebrafish embryos or larvae and that required in mammals. Here, we measured Ce for developmental toxicity agents every 24 h starting at 24 h post fertilization (hpf). We found a high correlation (R 2: 0.87-0.96) between log [Ce/Cw] and the n-octanol-water distribution coefficient at pH 7 (logD) of each drug at all time points up to 120 hpf. We used this relationship to estimate the Ce values of the 21 positive-control reference drugs listed in ICH guidelines on reproductive and developmental toxicity studies (ICH S5). We then calculated the area under the Ce-time curve in zebrafish (zAUC) for each drug from the regression equation between log [Ce/Cw] and logD and compared it with the AUC at the no-observed-adverse-effect level in rats and rabbits and at the effective dose in humans described in ICH S5. The log of the calculated zAUC for the 14 drugs identified as positive in the zebrafish developmental toxicity test was relatively highly positively correlated with the log [AUC] for rats, rabbits, and humans. These findings provide important and positive information on the applicability of the zebrafish embryo developmental toxicity test as an alternative method of EFD testing. (267 words).

20.
Environ Technol ; : 1-12, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39092595

RESUMO

This is the first record on literature to use biochar as support for CoFe2O4 to applicate and evaluate it as photocatalyst for degradation of organic pollutants. The support was verified by XRD, FT-IR, SEM, EDS and band gap. Composites CFO1BQ3, CFO1BQ1, and CFO3BQ1 showed 100% degradation in 60 min. This outstanding performance can be related to the drop in band gap energy and recombination rate of e¯/h + . The composites showed better efficiency when compared to pure CoFe2O4 (∼78%). This might be associate to the fact that biochar has a high concentration of phenolic, hydroxyl and carboxylic functional groups on its surface. In this reaction h+, O2•-, and •OH were the reactive species involved in the degradation. The toxicity of ponceau was tested before and after the treatment, through biochemical biomarkers in Danio rerio fish. In general, the treatment proved to be efficient in reducing ponceau toxicity in D. rerio fish.

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