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1.
Int J Mol Sci ; 22(12)2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34203824

RESUMO

In drug discovery, often animal models are used that mimic human diseases as closely as possible. These animal models can be used to address various scientific questions, such as testing and evaluation of new drugs, as well as understanding the pathogenesis of diseases. Currently, the most commonly used animal models in the field of fibrosis are rodents. Unfortunately, rodent models of fibrotic disease are costly and time-consuming to generate. In addition, present models are not very suitable for screening large compounds libraries. To overcome these limitations, there is a need for new in vivo models. Zebrafish has become an attractive animal model for preclinical studies. An expanding number of zebrafish models of human disease have been documented, for both acute and chronic diseases. A deeper understanding of the occurrence of fibrosis in zebrafish will contribute to the development of new and potentially improved animal models for drug discovery. These zebrafish models of fibrotic disease include, among others, cardiovascular disease models, liver disease models (categorized into Alcoholic Liver Diseases (ALD) and Non-Alcoholic Liver Disease (NALD)), and chronic pancreatitis models. In this review, we give a comprehensive overview of the usage of zebrafish models in fibrotic disease studies, highlighting their potential for high-throughput drug discovery and current technical challenges.


Assuntos
Modelos Animais de Doenças , Fibrose/patologia , Peixe-Zebra/fisiologia , Animais , Fibrose/genética
2.
Ecotoxicol Environ Saf ; 220: 112416, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34119928

RESUMO

Numerous byproducts resulting from chlorinated disinfection are constantly being generated during water treatment processes. The potential risks of these new emerging pollutions remain largely unknown. Here, we determined the risks of chlorinated disinfection byproducts of diazepam (DZP) in the cellular and zebrafish exposure experiments. The cytotoxicity of disinfection byproducts (MACB and MBCC) was greater than DZP in macrophage raw 264.7 cells at 10 mg/L. We further found that the effects of MBCC on the metabolism of glycine, serine, threonine and riboflavin were far greater than DZP by the targeted metabolomics methods. Moreover, MBCC significantly decreased the peak amplitude of neuronal action potential in primary embryonic rat (Spragu-Dawley SD) hippocampal neurons. We finally determined behavioral toxicity of DZP and byproducts in zebrafish larvae. MBCC significantly decreased the maximal swim-activity and peak duration of zebrafish after 72 h exposure. Altogether, these findings indicate the MBCC pose serious pressures on public health.


Assuntos
Comportamento Animal/efeitos dos fármacos , Diazepam/toxicidade , Desinfetantes/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/fisiologia , Animais , Diazepam/química , Desinfetantes/química , Halogenação , Hipocampo/efeitos dos fármacos , Hipocampo/patologia , Metaboloma/efeitos dos fármacos , Camundongos , Neurônios/efeitos dos fármacos , Células RAW 264.7 , Ratos , Natação/fisiologia , Poluentes Químicos da Água/química , Peixe-Zebra/crescimento & desenvolvimento , Peixe-Zebra/metabolismo
3.
Int J Mol Sci ; 22(11)2021 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-34070932

RESUMO

The neuronal networks that generate locomotion are well understood in swimming animals such as the lamprey, zebrafish and tadpole. The networks controlling locomotion in tetrapods remain, however, still enigmatic with an intricate motor pattern required for the control of the entire limb during the support, lift off, and flexion phase, and most demandingly when the limb makes contact with ground again. It is clear that the inhibition that occurs between bursts in each step cycle is produced by V2b and V1 interneurons, and that a deletion of these interneurons leads to synchronous flexor-extensor bursting. The ability to generate rhythmic bursting is distributed over all segments comprising part of the central pattern generator network (CPG). It is unclear how the rhythmic bursting is generated; however, Shox2, V2a and HB9 interneurons do contribute. To deduce a possible organization of the locomotor CPG, simulations have been elaborated. The motor pattern has been simulated in considerable detail with a network composed of unit burst generators; one for each group of close synergistic muscle groups at each joint. This unit burst generator model can reproduce the complex burst pattern with a constant flexion phase and a shortened extensor phase as the speed increases. Moreover, the unit burst generator model is versatile and can generate both forward and backward locomotion.


Assuntos
Geradores de Padrão Central/fisiologia , Interneurônios/fisiologia , Locomoção/fisiologia , Atividade Motora/fisiologia , Redes Neurais de Computação , Medula Espinal/fisiologia , Animais , Gatos , Geradores de Padrão Central/citologia , Simulação por Computador , Extremidades/inervação , Extremidades/fisiologia , Humanos , Interneurônios/citologia , Lampreias/fisiologia , Larva/fisiologia , Neurônios Motores/citologia , Neurônios Motores/fisiologia , Músculo Esquelético/inervação , Músculo Esquelético/fisiologia , Roedores/fisiologia , Medula Espinal/citologia , Peixe-Zebra/fisiologia
4.
J Vis Exp ; (170)2021 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-33938895

RESUMO

Neurodegenerative diseases are age-dependent, debilitating, and incurable. Recent reports have also correlated hyperglycemia with changes in memory and/or cognitive impairment. We have modified and developed a three-chamber choice cognitive task similar to that used with rodents for use with hyperglycemic zebrafish. The testing chamber consists of a centrally located starting chamber and two choice compartments on either side, with a shoal of conspecifics used as the reward. We provide data showing that once acquired, zebrafish remember the task at least 8 weeks later. Our data indicate that zebrafish respond robustly to this reward, and we have identified cognitive deficits in hyperglycemic fish after 4 weeks of treatment. This behavioral assay may also be applicable to other studies related to cognition and memory.


Assuntos
Comportamento Animal , Comportamento de Escolha , Modelos Biológicos , Análise e Desempenho de Tarefas , Peixe-Zebra/fisiologia , Aclimatação , Animais , Disfunção Cognitiva , Discriminação Psicológica , Hiperglicemia/patologia
5.
Aquat Toxicol ; 235: 105814, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33933832

RESUMO

Microplastics (MPs, <5 mm) have been frequently detected in aquatic ecosystems, representing both health and ecological concerns. However data about the combined effects of MPs and other contaminants is still limited. This study aimed to evaluate the impact of MPs and the heavy metal copper (Cu) on zebrafish (Danio rerio) larvae development and behavior. Zebrafish embryos were subchronically exposed to MPs (2 mg/L), two sub-lethal concentrations of Cu (60 and 125 µg/L) and binary mixtures of MPs and Cu using the same concentrations, from 2-h post fertilization until 14 days post fertilization. Lethal and sub-lethal responses (mortality, hatching, body length) were evaluated during the embryogenesis period, and locomotor, avoidance, anxiety and shoaling behaviors, and acetylcholinesterase (AChE) activity were measured at 14 dpf. The results showed that survival of larvae was reduced in groups exposed to MPs, Cu and Cu+MPs. Regarding the behavioral patterns, the higher Cu concentration and mixtures decreased significantly the mean speed, the total distance traveled and the absolute turn angle, demonstrating an adverse effect on swimming competence of zebrafish larvae. Exposure to MPs and Cu, alone or combined, also affected avoidance behavior of zebrafish, with larvae not reacting to the aversive stimulus. There was a significant inhibition of AChE activity in larvae exposed to all experimental groups, compared to the control group. Moreover, a higher inhibition of AChE was noticed in larvae exposed to MPs and both Cu+MPs groups, comparatively to the Cu alone groups. Our findings demonstrate the adverse effects of MPs, alone or co-exposed with Cu, on fish early life stages behavior. This study highlights that MPs and heavy metals may have significant impacts on fish population fitness by disrupting locomotor and avoidance behaviors.


Assuntos
Cobre/toxicidade , Microplásticos/toxicidade , Poluentes Químicos da Água/toxicidade , Acetilcolinesterase , Animais , Comportamento Animal/efeitos dos fármacos , Ecossistema , Larva/efeitos dos fármacos , Metais Pesados , Plásticos , Natação , Peixe-Zebra/fisiologia
6.
Aquat Toxicol ; 235: 105815, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33838494

RESUMO

Tris(4-chlorophenyl)methanol (TCPMOH) is a water contaminant with unknown etiology, but is believed to be a byproduct of DDT manufacturing. It is highly persistent in the environment, and bioaccumulates in marine species. TCPMOH has also been measured in human breast milk, which poses a risk for developing infants. However, almost no toxicity data is currently available. In this study, we investigate the hazard posed by developmental TCPMOH exposures using the zebrafish model (Danio rerio). Zebrafish (Danio rerio) embryos were exposed to 0, 0.1, 0.5, 1, or 5 µM TCPMOH beginning at 24 h post fertilization (hpf). Embryonic mortality and incidence of morphological deformities increased in a concentration-dependent manner with TCPMOH exposure. RNA sequencing assessed changes in gene expression associated with acute (4 hour) exposures to 50 nM TCPMOH. Developmental exposure to TCPMOH decreased expression of ahr2, as well as metabolic enzymes cyp1a1, cyp1b1, cyp1c1, cyp1c2, and cyp2y3 (p<0.05). These findings were concordant with decreased Cyp1a1 induction measured by the ethoxyresorufin-O-deethylase (EROD) assay (p<0.05). Pathways associated with xenobiotic metabolism, lipid metabolism, and transcriptional and translational regulation were decreased. Pathways involved in DNA replication and repair, carbohydrate metabolism, and endocrine function were upregulated. Overall, this study demonstrates that TCPMOH is acutely toxic to zebrafish embryos at elevated concentrations.


Assuntos
Compostos de Tritil/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Citocromo P-450 CYP1A1/metabolismo , Citocromo P-450 CYP1B1/genética , Ecotoxicologia , Embrião não Mamífero/metabolismo , Desenvolvimento Embrionário , Humanos , Inativação Metabólica , Metanol/metabolismo , Ativação Transcricional , Peixe-Zebra/metabolismo , Peixe-Zebra/fisiologia , Proteínas de Peixe-Zebra/genética
7.
Aquat Toxicol ; 235: 105838, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33910148

RESUMO

Dibutyl phthalate (DBP) and diisobutyl phthalate (DiBP) have been reported to exhibit reproductive toxicity in vertebrates. However, the combined effect of DBP and DiBP on offspring of exposed parents remains unclear, especially for aquatic organisms such as fish. The aims of this study were to assess the effects of parental co-exposure to DBP and DiBP on early development of zebrafish offspring, and to explore the potential molecular mechanisms involved. The early developmental indicators and transcriptomic profiles of F1 larvae were examined after parental exposure to DBP, DiBP and their mixtures (Mix) for 30 days. Results showed that parental exposure to DBP and DiBP, alone or in combination, resulted in increased hatchability at 48 hpf and heart rate at 96 hpf, and increased the prevalence of malformations and mortality in F1 larvae. Generalized linear model (GLM) suggested an antagonistic interactive effect between DBP and DiBP on mortality and malformations of F1 larvae. The transcriptomic analysis revealed that the molecular mechanisms of parental co-exposure were different from those of either chemical alone. Disruption of molecular functions involved unfolded protein binding, E-box binding and photoreceptor activity in F1 larvae. These findings provide initial insights in the potential mechanism of action of parental co-exposure to DBP and DiBP.


Assuntos
Dibutilftalato/análogos & derivados , Dibutilftalato/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Perfilação da Expressão Gênica , Reprodução/efeitos dos fármacos , Transcriptoma , Peixe-Zebra/genética , Peixe-Zebra/fisiologia
8.
Int J Mol Sci ; 22(5)2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33801205

RESUMO

Following an injury, axons of both the central nervous system (CNS) and peripheral nervous system (PNS) degenerate through a coordinated and genetically conserved mechanism known as Wallerian degeneration (WD). Unlike central axons, severed peripheral axons have a higher capacity to regenerate and reinnervate their original targets, mainly because of the favorable environment that they inhabit and the presence of different cell types. Even though many aspects of regeneration in peripheral nerves have been studied, there is still a lack of understanding regarding the dynamics of axonal degeneration and regeneration, mostly due to the inherent limitations of most animal models. In this scenario, the use of zebrafish (Danio rerio) larvae combined with time-lapse microscopy currently offers a unique experimental opportunity to monitor the dynamics of the regenerative process in the PNS in vivo. This review summarizes the current knowledge and advances made in understanding the dynamics of the regenerative process of PNS axons. By using different tools available in zebrafish such as electroablation of the posterior lateral line nerve (pLLn), and laser-mediated transection of motor and sensory axons followed by time-lapse microscopy, researchers are beginning to unravel the complexity of the spatiotemporal interactions among different cell types during the regenerative process. Thus, understanding the cellular and molecular mechanisms underlying the degeneration and regeneration of peripheral nerves will open new avenues in the treatment of acute nerve trauma or chronic conditions such as neurodegenerative diseases.


Assuntos
Axônios/metabolismo , Regeneração Nervosa , Neuroglia/metabolismo , Traumatismos dos Nervos Periféricos/patologia , Peixe-Zebra/fisiologia , Animais , Traumatismos dos Nervos Periféricos/terapia
9.
Int J Mol Sci ; 22(7)2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33805345

RESUMO

Acrylamide is a commonly used industrial chemical that is known to be neurotoxic to mammals. However, its developmental toxicity is rarely assessed in mammalian models because of the cost and complexity involved. We used zebrafish to assess the neurotoxicity, developmental and behavioral toxicity of acrylamide. At 6 h post fertilization, zebrafish embryos were exposed to four concentrations of acrylamide (10, 30, 100, or 300 mg/L) in a medium for 114 h. Acrylamide caused developmental toxicity characterized by yolk retention, scoliosis, swim bladder deficiency, and curvature of the body. Acrylamide also impaired locomotor activity, which was measured as swimming speed and distance traveled. In addition, treatment with 100 mg/L acrylamide shortened the width of the brain and spinal cord, indicating neuronal toxicity. In summary, acrylamide induces developmental toxicity and neurotoxicity in zebrafish. This can be used to study acrylamide neurotoxicity in a rapid and cost-efficient manner.


Assuntos
Acrilamida/toxicidade , Embrião não Mamífero/efeitos dos fármacos , Síndromes Neurotóxicas/fisiopatologia , Peixe-Zebra/crescimento & desenvolvimento , Acrilamida/farmacologia , Sacos Aéreos/patologia , Animais , Animais Geneticamente Modificados , Modelos Animais de Doenças , Embrião não Mamífero/fisiopatologia , Desenvolvimento Embrionário/efeitos dos fármacos , Síndromes Neurotóxicas/etiologia , Escoliose/etiologia , Natação , Peixe-Zebra/fisiologia
10.
Int J Mol Sci ; 22(6)2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33809683

RESUMO

Low temperature stress represents a major threat to the lives of both farmed and wild fish species. However, biological pathways determining the development of cold resistance in fish remain largely unknown. Zebrafish larvae at 96 hpf were exposed to lethal cold stress (10 °C) for different time periods to evaluate the adverse effects at organism, tissue and cell levels. Time series RNA sequencing (RNA-seq) experiments were performed to delineate the transcriptomic landscape of zebrafish larvae under cold stress and during the subsequent rewarming phase. The genes regulated by cold stress were characterized by progressively enhanced or decreased expression, whereas the genes associated with rewarming were characterized by rapid upregulation upon return to normal temperature (28 °C). Genes such as trib3, dusp5 and otud1 were identified as the representative molecular markers of cold-induced damages through network analysis. Biological pathways involved in cold stress responses were mined from the transcriptomic data and their functions in regulating cold resistance were validated using specific inhibitors. The autophagy, FoxO and MAPK (mitogen-activated protein kinase) signaling pathways were revealed to be survival pathways for enhancing cold resistance, while apoptosis and necroptosis were the death pathways responsible for cold-induced mortality. Functional mechanisms of the survival-enhancing factors Foxo1, ERK (extracellular signal-regulated kinase) and p38 MAPK were further characterized by inhibiting their activities upon cold stress and analyzing gene expression though RNA-seq. These factors were demonstrated to determine the cold resistance of zebrafish through regulating apoptosis and p53 signaling pathway. These findings have provided novel insights into the stress responses elicited by lethal cold and shed new light on the molecular mechanisms underlying cold resistance of fish.


Assuntos
Adaptação Fisiológica , Temperatura Baixa , Transdução de Sinais , Peixe-Zebra/fisiologia , Adaptação Fisiológica/genética , Animais , Biomarcadores/metabolismo , Análise por Conglomerados , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Ontologia Genética , Larva/genética , Transdução de Sinais/genética , Análise de Sobrevida , Transcrição Genética , Transcriptoma/genética , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
11.
Int J Mol Sci ; 22(6)2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33809722

RESUMO

Medullary thyroid carcinoma (MTC) is a tumor deriving from the thyroid C cells. Vandetanib (VAN) and cabozantinib (CAB) are two tyrosine kinase inhibitors targeting REarranged during Transfection (RET) and other kinase receptors and are approved for the treatment of advanced MTC. We aim to compare the in vitro and in vivo anti-tumor activity of VAN and CAB in MTC. The effects of VAN and CAB on viability, cell cycle, and apoptosis of TT and MZ-CRC-1 cells are evaluated in vitro using an MTT assay, DNA flow cytometry with propidium iodide, and Annexin V-FITC/propidium iodide staining, respectively. In vivo, the anti-angiogenic potential of VAN and CAB is evaluated in Tg(fli1a:EGFP)y1 transgenic fluorescent zebrafish embryos by analyzing the effects on the physiological development of the sub-intestinal vein plexus and the tumor-induced angiogenesis after TT and MZ-CRC-1 xenotransplantation. VAN and CAB exert comparable effects on TT and MZ-CRC-1 viability inhibition and cell cycle perturbation, and stimulated apoptosis with a prominent effect by VAN in MZ-CRC-1 and CAB in TT cells. Regarding zebrafish, both drugs inhibit angiogenesis in a dose-dependent manner, in particular CAB shows a more potent anti-angiogenic activity than VAN. To conclude, although VAN and CAB show comparable antiproliferative effects in MTC, the anti-angiogenic activity of CAB appears to be more relevant.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Anilidas/uso terapêutico , Carcinoma Neuroendócrino/tratamento farmacológico , Piperidinas/uso terapêutico , Piridinas/uso terapêutico , Quinazolinas/uso terapêutico , Neoplasias da Glândula Tireoide/tratamento farmacológico , Peixe-Zebra/fisiologia , Anilidas/farmacologia , Animais , Apoptose/efeitos dos fármacos , Carcinoma Neuroendócrino/irrigação sanguínea , Carcinoma Neuroendócrino/patologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Embrião não Mamífero/irrigação sanguínea , Embrião não Mamífero/efeitos dos fármacos , Humanos , Neovascularização Patológica/tratamento farmacológico , Neovascularização Fisiológica/efeitos dos fármacos , Piridinas/farmacologia , Neoplasias da Glândula Tireoide/irrigação sanguínea , Neoplasias da Glândula Tireoide/patologia , Peixe-Zebra/embriologia
12.
Biomolecules ; 11(2)2021 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-33672636

RESUMO

The prevalence of patients suffering from mental disorders is substantially increasing in recent years and represents a major burden to society. The underlying causes and neuronal circuits affected are complex and difficult to unravel. Frequent disorders such as depression, schizophrenia, autism, and bipolar disorder share links to the habenular neural circuit. This conserved neurotransmitter system relays cognitive information between different brain areas steering behaviors ranging from fear and anxiety to reward, sleep, and social behaviors. Advances in the field using the zebrafish model organism have uncovered major genetic mechanisms underlying the formation of the habenular neural circuit. Some of the identified genes involved in regulating Wnt/beta-catenin signaling have previously been suggested as risk genes of human mental disorders. Hence, these studies on habenular genetics contribute to a better understanding of brain diseases. We are here summarizing how the gained knowledge on the mechanisms underlying habenular neural circuit development can be used to introduce defined manipulations into the system to study the functional behavioral consequences. We further give an overview of existing behavior assays to address phenotypes related to mental disorders and critically discuss the power but also the limits of the zebrafish model for identifying suitable targets to develop therapies.


Assuntos
Habenula/fisiologia , Transtornos Mentais/genética , Peixe-Zebra/genética , Animais , Ansiedade , Axônios/metabolismo , Comportamento Animal , Depressão/tratamento farmacológico , Depressão/metabolismo , Depressão/fisiopatologia , Modelos Animais de Doenças , Habenula/metabolismo , Transtornos Mentais/metabolismo , Mutação , Rede Nervosa , Neurogênese , Neurônios/metabolismo , Neurotransmissores , Fenótipo , Comportamento Social , Proteínas Wnt/metabolismo , Via de Sinalização Wnt , Peixe-Zebra/fisiologia , Proteínas de Peixe-Zebra/genética
13.
Oxid Med Cell Longev ; 2021: 3923625, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33680282

RESUMO

Scavenging of oxidative stress by antioxidants may provide a therapeutic strategy for nonalcoholic fatty liver disease (NAFLD). Increasing evidence is supporting the potential application of natural resourced polysaccharides as promising prevention or treatment strategies against NAFLD. In the current study, an acidic heteropolysaccharide, LFP-a1, was isolated and purified from Lycii fructus with successively hot water refluxing extraction, alcohol precipitation, protein removal, and DEAE-52 cellulose chromatographic separation. LFP-a1 was a complicated structured polysaccharide with an average MW of 4.74 × 104 Da and composed of 6 monosaccharides and 1 uronic acid. Preexposure of LFP-a1 could increase the cell viability and reverse the abnormal oxidative stress though inhibition of mitochondrial-mediated apoptotic pathway and correction of cell cycle progression against H2O2 hepatoxicity in NAFLD model L02 cells. Consistently, in vivo study in thioacetamide- (TAA-) induced NAFLD model zebrafish larvae showed LFP-a1 preserved the liver integrity and alleviated TAA-induced oxidative stress through downregulation of abnormal apoptosis. These observations indicated the hepatoprotective activity of LFP-a1, which may be applied for the prevention or treatment of NAFLD or other oxidative stress-related diseases.


Assuntos
Hepatócitos/patologia , Fígado/patologia , Lycium/química , Estresse Oxidativo/efeitos dos fármacos , Polissacarídeos/farmacologia , Substâncias Protetoras/farmacologia , Peixe-Zebra/fisiologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Linhagem Celular , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Peróxido de Hidrogênio/toxicidade , Larva/efeitos dos fármacos , Larva/genética , Larva/fisiologia , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/patologia , Polissacarídeos/isolamento & purificação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Peixe-Zebra/genética
14.
J Vis Exp ; (168)2021 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-33645560

RESUMO

Sensory systems gather cues essential for directing behavior, but animals must decipher what information is biologically relevant. Locomotion generates reafferent cues that animals must disentangle from relevant sensory cues of the surrounding environment. For example, when a fish swims, flow generated from body undulations is detected by the mechanoreceptive neuromasts, comprising hair cells, that compose the lateral line system. The hair cells then transmit fluid motion information from the sensor to the brain via the sensory afferent neurons. Concurrently, corollary discharge of the motor command is relayed to hair cells to prevent sensory overload. Accounting for the inhibitory effect of predictive motor signals during locomotion is, therefore, critical when evaluating the sensitivity of the lateral line system. We have developed an in vivo electrophysiological approach to simultaneously monitor posterior lateral line afferent neuron and ventral motor root activity in zebrafish larvae (4-7 days post fertilization) that can last for several hours. Extracellular recordings of afferent neurons are achieved using the loose patch clamp technique, which can detect activity from single or multiple neurons. Ventral root recordings are performed through the skin with glass electrodes to detect motor neuron activity. Our experimental protocol provides the potential to monitor endogenous or evoked changes in sensory input across motor behaviors in an intact, behaving vertebrate.


Assuntos
Sistema da Linha Lateral/inervação , Neurônios Aferentes/fisiologia , Natação/fisiologia , Peixe-Zebra/fisiologia , Animais , Eletrodos , Fenômenos Eletrofisiológicos , Larva/fisiologia , Neurônios Motores/fisiologia
15.
Molecules ; 26(4)2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33672019

RESUMO

Putrajeevak (Putranjiva roxburghii Wall.; synonym Drypetes roxburghii (Wall.) Hurus) seeds have been used since ancient times in the treatment of infertility in the Ayurvedic system of medicine in India. In this study, the oil component of Putrajeevak seeds (PJSO) was extracted using the supercritical fluid extraction (SCFE) method using liquid CO2 and the constituents were analyzed using gas chromatography-flame ionized detectorand high-performance thin-layer chromatography. PJSO contained trace amounts of ß-sitosterol with oleic and linoleic acids as the major fatty acid constituents. Male and female zebrafish were mutagenized with N-ethyl-N-nitrosourea (ENU) and fish that produced less than 20 viable embryos were selected for the study. SCFE oil extracts from the P. roxburghii seeds were used in this study to reverse fertility impairment. The mutant fish were fed with PJSO for a period of 14 days and the rates of fertility, conception, and fecundity were determined with wild-type healthy fish as a breeding partner. Treatment with PJSO increased the ovarian follicle count as well as the number of mature eggs, while reducing the number of ovarian cysts. Sperm count as well as sperm motility were greatly enhanced in the ENU-mutagenized male zebrafish when treated with PJSO. The results obtained in this study demonstrate the effectiveness of P. roxburghii seed oil in reversing impaired fertility in both male and female zebrafish models.


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Euphorbiaceae/química , Fertilidade/fisiologia , Sementes/química , Peixe-Zebra/fisiologia , Animais , Modelos Animais de Doenças , Ácidos Graxos/análise , Ácidos Graxos/química , Feminino , Fertilidade/efeitos dos fármacos , Inflamação/tratamento farmacológico , Inflamação/patologia , Masculino , Ovário/fisiologia , Óvulo/fisiologia , Pelve/patologia , Óleos Vegetais/química , Óleos Vegetais/farmacologia , Óleos Vegetais/uso terapêutico , Sitosteroides/análise , Sitosteroides/química , Testículo/efeitos dos fármacos , Testículo/patologia
16.
Eur J Med Chem ; 216: 113307, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33652354

RESUMO

Androgen receptor (AR) is an effective therapeutic target for the treatment of prostate cancer. We report herein the design, synthesis, and biological evaluation of highly effective proteolysis targeting chimeras (PROTAC) androgen receptor (AR) degraders, such as compound A031. It could induce the degradation of AR protein in VCaP cell lines in a time-dependent manner, achieving the IC 50 value of less than 0.25 µM. The A031 is 5 times less toxic than EZLA and works with an appropriate half-life (t 1/2) or clearance rate (Cl). Also, it has a significant inhibitory effect on tumor growth in zebrafish transplanted with human prostate cancer (VCaP). Therefore, A031 provides a further idea of developing novel drugs for prostate cancer.


Assuntos
Antagonistas de Receptores de Andrógenos/química , Receptores Androgênicos/metabolismo , Antagonistas de Receptores de Andrógenos/farmacocinética , Antagonistas de Receptores de Andrógenos/farmacologia , Antagonistas de Receptores de Andrógenos/uso terapêutico , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Desenho de Fármacos , Avaliação Pré-Clínica de Medicamentos , Meia-Vida , Humanos , Masculino , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia , Proteólise , Ratos , Ratos Sprague-Dawley , Receptores Androgênicos/genética , Relação Estrutura-Atividade , Taxa de Sobrevida , Transplante Heterólogo , Peixe-Zebra/crescimento & desenvolvimento , Peixe-Zebra/fisiologia
17.
Ecotoxicol Environ Saf ; 215: 112176, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33780780

RESUMO

Both tetrabromobisphenol A (TBBPA) and titanium dioxide nanoparticle (TiO2 NP) have widespread commercial applications, resulting in their ubiquitous co-presence in the environment and biota. Although environmental chemicals exist as mixtures, toxicity studies are nearly always conducted with single chemicals. Few studies explore potential interactions of different chemical mixtures. In this study, we employ the sensitive developing nerve system in zebrafish to assess the neurotoxicity of TBBPA/TiO2 NP mixtures. Specifically, zebrafish embryos were exposed to solvent control (0.1% DMSO), 2 µM TBBPA, 0.1 mg/L TiO2 NP, and their mixture from 8 to 120 h post fertilization (hpf), and motor/social behavioral assessments were conducted on embryos/larvae at different developmental stages. Our results showed that TBBPA/TiO2 NP single or co-exposures increased spontaneous movement, decreased touch response and swim speed, and affected social behaviors of light/dark preference, shoaling, mirror attack and social contact. In particular, many of these phenotypes were manifested with higher magnitude of changes from the mixture exposure. These behavioral deficits were also accompanied with increased cell death in olfactory region and neuromasts in the lateral line system, increased ROS in gallbladder, pancreas, liver, and intestine, as well as increased lipid peroxidation and decreased ATP levels in whole larval tissue homogenates. Further, genes coding for key cell apoptosis marker and antioxidant enzyme were significantly upregulated by these two chemicals, in particular to their mixture. Interestingly, the co-presence of TBBPA also increased the mean particle size of TiO2 NP in the exposure solutions and the TiO2 NP content in larval tissue. Together, our analysis suggests that TBBPA/TiO2 NP induced behavioral changes may be due to physical accumulation of these two chemicals in the target organs, and TiO2 NP may serve as carriers for increased accumulation of TBBPA. To conclude, we demonstrated that TBBPA/TiO2 NP together cause increased bioaccumulation of TiO2, and heightened responses in behavior, cell apoptosis and oxidative stress. Our findings also highlight the importance of toxicity assessment using chemical mixtures.


Assuntos
Nanopartículas/toxicidade , Bifenil Polibromatos/toxicidade , Titânio/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/fisiologia , Animais , Antioxidantes/metabolismo , Apoptose , Bioacumulação , Larva/metabolismo , Peroxidação de Lipídeos , Fígado/metabolismo , Estresse Oxidativo , Comportamento Social
18.
Carbohydr Polym ; 259: 117749, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33673979

RESUMO

The increasing world-wide demand for food has prompted the development of efficient and environmentally friendly pesticide formulations. In this article, we have prepared CMC-g-PRSG carrier based on two compounds from natural materials carboxymethyl cellulose (CMC) and rosin (RS). The model pesticide avermectin (AVM) was encapsulated through hydrophobic interaction, and self-assembled to form nanopesticide AVM@CMC-g-PRSG with an average particle size of 167 nm. The prepared nanopesticide displays enhanced dispersibility and stability of AVM in water, and can effectively adhere to the leaves to prevent loss. The release rate of AVM encapsulated in the nanocarrier can be controlled by adjusting pH, and AVM half-life under ultraviolet radiation shows a 3-fold increase allowing control of pests for prolonged periods of time in practical applications. Biological safety tests showed that AVM@CMC-g-PRSG effectively reduces the toxicity of AVM to aquatic animals. Therefore, the cheap and degradable carrier CMC-g-PRSG can improve the effect of hydrophobic pesticides.


Assuntos
Carboximetilcelulose Sódica/química , Portadores de Fármacos/química , Resinas Vegetais/química , Animais , Liberação Controlada de Fármacos , Meia-Vida , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Ivermectina/análogos & derivados , Ivermectina/química , Ivermectina/metabolismo , Ivermectina/farmacologia , Larva/efeitos dos fármacos , Nanopartículas/química , Tamanho da Partícula , Controle de Pragas/métodos , Praguicidas/química , Praguicidas/metabolismo , Praguicidas/farmacologia , Raios Ultravioleta , Peixe-Zebra/crescimento & desenvolvimento , Peixe-Zebra/fisiologia
19.
Carbohydr Polym ; 259: 117710, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33673989

RESUMO

Harmful algal blooms induce severe environmental problems. It is challenging to remove algae by the current available treatments involving complicate process and costly instruments. Here, we developed a CaO2@PEG-loaded water-soluble self-branched chitosan (CP-SBC) system, which can remove algae from water in one-step without additional instrumentation. This approach utilizes a novel flocculant (self-branched chitosan) integrated with flotation function (induced by CaO2@PEG). CP-SBC exhibited better flocculation performance than commercial flocculants, which is attributed to the enhanced bridging and sweeping effect of branched chitosan. CP-SBC demonstrated outstanding biocompatibility, which was verified by zebrafish test and algae activity test. CaO2@PEG-loaded self-branched chitosan can serve as an "Air flotation system" to spontaneous float the flocs after flocculation by sustainably released O2. Furthermore, CP-SBC can improve water quality through minimizing dissolved oxygen depletion and reducing total phosphorus concentrations.


Assuntos
Quitosana/química , Proliferação Nociva de Algas/fisiologia , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Compostos de Cálcio/química , Floculação/efeitos dos fármacos , Proliferação Nociva de Algas/efeitos dos fármacos , Cinética , Larva/efeitos dos fármacos , Óxidos/química , Oxigênio/química , Fósforo/química , Polietilenoglicóis/química , Porosidade , Peixe-Zebra/crescimento & desenvolvimento , Peixe-Zebra/fisiologia
20.
Methods Mol Biol ; 2218: 1-9, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33606218

RESUMO

Zebrafish ovarian follicles are mainly composed of the oocyte and a thin layer of follicle cells. Recent studies have demonstrated extensive cell-cell interactions between the oocyte and surrounding follicle layer and that the two compartments communicate mostly through paracrine factors. To understand the paracrine communication within the follicle, it is essential to know the spatial expression patterns of genes in the two compartments. However, since the follicle layer is extremely thin and the oocytes are enormous in size in fish, it is often difficult to detect gene expression by traditional methods such as in situ hybridization. Separation of the oocyte and surrounding follicle layer followed by RT-PCR detection provides a sensitive way to reveal the expression of individual genes in the two compartments of the follicle. This chapter introduces a method for mechanic separation of the oocyte and follicle layer at full-grown stage for expression analysis. Since fish have similar follicle structure, this method may also be used in other species as well.


Assuntos
Expressão Gênica/fisiologia , Oócitos/fisiologia , Folículo Ovariano/fisiologia , Peixe-Zebra/fisiologia , Animais , Feminino , Ovário/fisiologia , Comunicação Parácrina/fisiologia
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