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1.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 44(9): 968-975, 2019 Sep 28.
Artigo em Chinês | MEDLINE | ID: mdl-31645484

RESUMO

OBJECTIVE: To explore the effects of KIAA0196 gene on cardiac development and the establishment of zebrafish strain.
 Methods: Peripheral blood and gDNA from patients were extracted. Copy number variation analysis and target sequencing were conducted to screen candidate genes. The KIAA0196 knockout zebrafish was generated by CRISPR/Cas9 to detect whether KIAA0196 deficiency could affect cardiac development. Finally, the wild-type and mutant zebrafish were anatomized and histologically stained to observe the phenotype of heart defects.
 Results: The KIAA0196 knockout zebrafish strain was successfully constructed using CRISPR/Cas9 technology. After 60 hours fertilization, microscopic examination of KIAA0196 knockout zebrafish (heterozygote + homozygote) showed pericardial effusion, cardiac compression and severely curly tail. Compared with wild-type zebrafish, the hearts of mutant KIAA0196 zebrafish had cardiac defects including smaller atrium and larger ventricle, and the myocardial cells were looser.
 Conclusion: KIAA0196 gene plays an important regulatory role in the development of heart. It might be a candidate gene for congenital heart disease.


Assuntos
Cardiopatias Congênitas/genética , Proteínas de Peixe-Zebra/genética , Peixe-Zebra/genética , Animais , Variações do Número de Cópias de DNA , Coração , Humanos , Miócitos Cardíacos , Fenótipo , Proteínas
2.
Aquat Toxicol ; 215: 105287, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31491706

RESUMO

Gold nanoparticles are used as drug delivery vectors based on the assumption that they have low toxicity. Literature has, however, produced conflicting results over the last few years. As such, this study aimed to investigate the toxicological effects of nanogold (nAu) on several indicators that range from subcellular to whole-organism level. Gene regulation, changes in oxidative stress biomarkers and swimming performance were assessed in Danio rerio (zebrafish) following exposures to nAu. Adult zebrafish were exposed in vivo to nAu for 96 h and swimming performance measured post-exposure. Liver tissue was collected for DNA microarray and Real-Time Polymerase Chain Reactions (RT-PCR) analyses to determine changes in gene expression (catalase, superoxide dismutase and metallothioneins) and protein biomarker analyses (catalase, superoxide dismutase, acetylcholine esterase, malondialdehyde, cellular energy allocation and metallothionein) were performed on whole-body samples. Swimming behaviour was assessed in 1.1 L Tecniplast™ tanks for a period of six hours and videos were analysed using Noldus EthoVision software. Critical swimming speed was measured in a Loligo® swimming tunnel. The DNA microarray revealed that fish exposed to 20 mg/L differed most from the control group. At 20 mg/L there was a significant increase in gene expression for all genes analysed but this didn't translate to significant responses in protein biomarker levels except for an increase in protein carbonyl formation. The behaviour results demonstrated significant changes in distance moved, swimming speed, acceleration bouts, zone alterations and time spent within the top zone - responses that are usually observed in fish responding to toxicological stress. Furthermore, the critical swimming speed of exposed fish was decreased significantly compared to the control. Since swimming performance and social interaction among zebrafish is essential to their survival, whole-organism behaviour that suggests a toxicological response after exposure to nAu is in agreement with the genetic responses measured in this study.


Assuntos
Comportamento Animal/efeitos dos fármacos , Ouro/toxicidade , Nanopartículas Metálicas/toxicidade , Peixe-Zebra/fisiologia , Animais , Biomarcadores/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Nanopartículas Metálicas/ultraestrutura , Família Multigênica , Músculos/efeitos dos fármacos , Natação , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/genética
3.
Gene ; 718: 144049, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31430520

RESUMO

The role of epigenetics in development has garnered attention in recent years due to their ability to modulate the embryonic developmental gene expression in response to the environmental cues. The epigenetic mechanisms - DNA methylation, histone modification, and non-coding RNAs have a unique impact on vertebrate development. Zebrafish, a model vertebrate organism is being used widely in developmental studies due to their high fecundability and rapid organogenesis. With increased studies on various aspects of epigenetics in development, this review gives a glimpse of the major epigenetic modifications and their role in zebrafish development. In this review, the basic mechanism behind each modification followed by their status in zebrafish has been reviewed. Further, recent advancements in the epigenetic aspect of zebrafish development have been discussed.


Assuntos
Metilação de DNA/fisiologia , Embrião não Mamífero/embriologia , Desenvolvimento Embrionário/fisiologia , Epigênese Genética/fisiologia , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Peixe-Zebra/embriologia , Animais , Histonas/genética , Histonas/metabolismo , Processamento de Proteína Pós-Traducional/fisiologia , Peixe-Zebra/genética
4.
Hum Genet ; 138(8-9): 993-1000, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31422478

RESUMO

In this brief commentary, we provide some of our thoughts and opinions on the current and future use of zebrafish to model human eye disease, dissect pathological progression and advance in our understanding of the genetic bases of microphthalmia, andophthalmia and coloboma (MAC) in humans. We provide some background on eye formation in fish and conservation and divergence across vertebrates in this process, discuss different approaches for manipulating gene function and speculate on future research areas where we think research using fish may prove to be particularly effective.


Assuntos
Oftalmopatias/genética , Peixe-Zebra/genética , Animais , Coloboma/genética , Humanos , Microftalmia/genética
5.
Aquat Toxicol ; 215: 105272, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31442592

RESUMO

A number of chemicals have been shown to affect epigenetic patterning and functions. Since epigenetic mechanisms regulate transcriptional networks, epigenetic changes induced by chemical exposure can represent early molecular events for long-term adverse physiological effects. Epigenetics has thus appeared as a research field of major interest within (eco)toxicological sciences. The present study aimed at measuring effects on epigenetic-related mechanisms of selected environmental chemicals (bisphenols, perfluorinated chemicals, methoxychlor, permethrin, vinclozolin and coumarin 47) in zebrafish embryos and liver cells (ZFL). Transcription of genes related to DNA methylation and histone modifications was measured and global DNA methylation was assessed in ZFL cells using the LUMA assay. The differences in results gathered from both models suggest that chemicals affect different mechanisms related to epigenetics in embryos and cells. In zebrafish embryos, exposure to bisphenol A, coumarin 47, methoxychlor and permethrin lead to significant transcriptional changes in epigenetic factors suggesting that they can impact early epigenome reprogramming related to embryonic development. In ZFL cells, significant transcriptional changes were observed upon exposure to all chemicals but coumarin 47; however, only perfluorooctane sulfonate induced significant effects on global DNA methylation. Notably, in contrast to the other tested chemicals, perfluorooctane sulfonate affected only the expression of the histone demethylase kdm5ba. In addition, kdm5ba appeared as a sensitive gene in zebrafish embryos as well. Taken together, the present results suggest a role for kdm5ba in regulating epigenetic patterns in response to chemical exposure, even though mechanisms remain unclear. To confirm these findings, further evidence is required regarding changes in site-specific histone marks and DNA methylation together with their long-term effects on physiological outcomes.


Assuntos
Embrião não Mamífero/metabolismo , Epigênese Genética , Fígado/metabolismo , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/embriologia , Peixe-Zebra/genética , Animais , Metilação de DNA/efeitos dos fármacos , Metilação de DNA/genética , Embrião não Mamífero/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Fígado/efeitos dos fármacos , Testes de Toxicidade Aguda , Transcrição Genética/efeitos dos fármacos
6.
Toxicol Lett ; 314: 43-52, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31310794

RESUMO

Thioredoxin is an evolutionarily conserved antioxidant protein that plays a crucial role for fundamental cellular processes and embryonic development. Growing evidence support that Thioredoxin influences cellular response to chemicals insults, particularly those accompanying oxidative stress. The mechanisms underlying the functions of Thioredoxin1 in the embryonic development under the environmental toxicant exposure remain, however, largely unexplored. We report here that thioredoxin1 becomes differentially expressed in zebrafish embryos after exposure to 9 out of 11 environmental chemicals. In situ gene expression analysis show that thioredoxin1 is expressed in neurons, olfactory epithelia, liver and swim bladder under normal conditions. After MeHg exposure, however, thioredoxin1 is ectopically induced in the hair cells of the lateral line and in epithelia cells of the pharynx. Knockdown of Thioredoxin1 induces hydrocephalus and increases cell apoptosis in the brain ventricular epithelia cells. In comparison with 5% malformation in embryos injected with control morpholino, MeHg induces more than 77% defects in Thioredoxin1 knockdown embryos. Our data suggest that there is an association between hydrocephalus and Thioredoxin1 malfunction in embryonic development, and provide valuable information to elucidate the protective role of Thioredoxin1 against chemicals disruption.


Assuntos
Encéfalo/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Hidrocefalia/induzido quimicamente , Tiorredoxinas/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/metabolismo , Animais , Animais Geneticamente Modificados , Apoptose/efeitos dos fármacos , Encéfalo/embriologia , Encéfalo/metabolismo , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/metabolismo , Embrião não Mamífero/patologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Regulação da Expressão Gênica no Desenvolvimento , Hidrocefalia/embriologia , Hidrocefalia/genética , Hidrocefalia/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Estresse Oxidativo/efeitos dos fármacos , Tiorredoxinas/genética , Peixe-Zebra/embriologia , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética
7.
BMC Evol Biol ; 19(1): 137, 2019 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-31269894

RESUMO

BACKGROUND: Previously, we have demonstrated that genes involved in ovarian function are highly conserved throughout evolution. In this study, we aimed to document the conservation of genes involved in spermatogenesis from flies to vertebrates and their expression profiles in vertebrates. RESULTS: We retrieved 379 Drosophila melanogaster genes that are functionally involved in male reproduction according to their mutant phenotypes and listed their vertebrate orthologs. 83% of the fly genes have at least one vertebrate ortholog for a total of 625 mouse orthologs. This conservation percentage is almost twice as high as the 42% rate for the whole fly genome and is similar to that previously found for genes preferentially expressed in ovaries. Of the 625 mouse orthologs, we selected 68 mouse genes of interest, 42 of which exhibited a predominant relative expression in testes and 26 were their paralogs. These 68 mouse genes exhibited 144 and 60 orthologs in chicken and zebrafish, respectively, gathered in 28 groups of paralogs. Almost two thirds of the chicken orthologs and half of the zebrafish orthologs exhibited a relative expression ≥50% in testis. Finally, our focus on functional in silico data demonstrated that most of these genes were involved in the germ cell process, primarily in structure elaboration/maintenance and in acid nucleic metabolism. CONCLUSION: Our work confirms that the genes involved in germ cell development are highly conserved across evolution in vertebrates and invertebrates and display a high rate of conservation of preferential testicular expression among vertebrates. Among the genes highlighted in this study, three mouse genes (Lrrc46, Pabpc6 and Pkd2l1) have not previously been described in the testes, neither their zebrafish nor chicken orthologs. The phylogenetic approach developed in this study finally allows considering new testicular genes for further fundamental studies in vertebrates, including model species (mouse and zebrafish).


Assuntos
Galinhas/genética , Evolução Molecular , Testículo/metabolismo , Peixe-Zebra/genética , Animais , Drosophila melanogaster/genética , Masculino , Camundongos , Filogenia , Espermatogênese/genética , Testículo/citologia
8.
Nat Commun ; 10(1): 3054, 2019 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-31296860

RESUMO

Two waves of DNA methylation reprogramming occur during mammalian embryogenesis; during preimplantation development and during primordial germ cell (PGC) formation. However, it is currently unclear how evolutionarily conserved these processes are. Here we characterise the DNA methylomes of zebrafish PGCs at four developmental stages and identify retention of paternal epigenetic memory, in stark contrast to the findings in mammals. Gene expression profiling of zebrafish PGCs at the same developmental stages revealed that the embryonic germline is defined by a small number of markers that display strong developmental stage-specificity and that are independent of DNA methylation-mediated regulation. We identified promoters that are specifically targeted by DNA methylation in somatic and germline tissues during vertebrate embryogenesis and that are frequently misregulated in human cancers. Together, these detailed methylome and transcriptome maps of the zebrafish germline provide insight into vertebrate DNA methylation reprogramming and enhance our understanding of the relationships between germline fate acquisition and oncogenesis.


Assuntos
Metilação de DNA , Regulação da Expressão Gênica no Desenvolvimento/genética , Células Germinativas/crescimento & desenvolvimento , Herança Paterna , Peixe-Zebra/genética , Animais , Animais Geneticamente Modificados , Embrião não Mamífero , Desenvolvimento Embrionário/genética , Epigênese Genética/fisiologia , Perfilação da Expressão Gênica , Regiões Promotoras Genéticas/genética , Sequenciamento Completo do Genoma
9.
Aquat Toxicol ; 214: 105224, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31255847

RESUMO

Polybrominated diphenyl ethers (PBDEs) are distributed throughout the environment. Despite a moratorium on their use, concentrations of PBDEs in the atmosphere and in residential environments remain high due to their persistence. The environmental health risks remain concerning and one of the major adverse effects is neurodevelopmental toxicity. However, the early response and effects of PBDEs exposure on the developing brain remain unknown. In the present study, we investigated the impacts of 2,2',4,4',5-pentabrominated diphenyl ether (BDE-99) on vascular growth and vascular barrier function with an emphasis on cerebral blood vessels, in the early life stages, using a zebrafish model. No general toxicity was observed in exposing zebrafish larvae to 0-0.5 µM BDE-99 at 72 hpf. BDE-99 exposure resulted in neither general toxicity nor pronounced developmental impairment in somatic blood vessels, including intersegmental vessels (ISV) and common cardinal veins (CCV). Meanwhile, both 0.05 µM and 0.5 µM of BDE-99 reduced cerebrovascular density as well as down-regulation of VEGFA and VEGFR2 in the head. In addition, BDE-99 exposure increased vascular leakage, both in cerebral and truncal vasculature at 72 hpf. The accentuated vascular permeability was observed in the head. The mRNA levels of genes encoding tight junction molecules decreased in the BDE-99-exposed larvae, and more robust reductions in Cldn5, Zo1 and Jam were detected in the head than in the trunk. Moreover, proinflammatory factors including TNF-α, IL-1ß and ICAM-1 were induced, and the expression of neurodevelopment-related genes was suppressed in the head following BDE-99 exposure. Taken together, these results reveal that developmental exposure to BDE-99 impedes cerebrovascular growth and disturbs vascular barrier formation. The cerebral vasculature in developing zebrafish, a more sensitive target for BDE-99, may be a promising tool for the assessment of the early neurodevelopmental effects due to PBDEs exposure.


Assuntos
Vasos Sanguíneos/efeitos dos fármacos , Exposição Ambiental , Éteres Difenil Halogenados/toxicidade , Peixe-Zebra/crescimento & desenvolvimento , Animais , Encéfalo/irrigação sanguínea , Encéfalo/crescimento & desenvolvimento , Permeabilidade Capilar/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Inflamação/genética , Inflamação/patologia , Larva/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Junções Íntimas/efeitos dos fármacos , Junções Íntimas/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/genética
10.
Aquat Toxicol ; 214: 105236, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31260825

RESUMO

Otolith consisting largely of calcium carbonate, fibrous and proteins, is vital for maintaining body balance and/or hearing of fish. The formation of otolith involves Ca2+ transport and deposition. In the present study, we investigated the effects of Cd2+ on otoliths development by using zebrafish embryos as model. The results showed that exposure to Cd2+ inhibited the utricular and saccular otoliths growth, indicated by reduced lateral areas. Swimming speeds were reduced and a losing balance control was observed in Cd2+ exposed larvae. The genes related to Ca2+ transport (e.g. plasma membrane Ca2+-ATPase isoform 2, pmca2; Ca2+-ATPase isoform 2, atp2b1a) and regulation (e.g. parathyroid hormone ligand type-1, pth1; stanniocalcin isoform 1, stc1) were significantly downregulated. However, the adverse effects of Cd2+ on otoliths growth and swimming activity can be protected by supplementation of Ca2+ in exposure medium. Body burden of Cd2+ in larvae was reduced upon the supplement with Ca2+. The overall results suggest that exposure to Cd2+ can inhibit influx of Ca2+, leading to less deposition of CaCO3 for otolith growth, and finally result in impaired balance control and swimming activity in zebrafish larvae.


Assuntos
Comportamento Animal , Cádmio/toxicidade , Exposição Ambiental , Membrana dos Otólitos/crescimento & desenvolvimento , Peixe-Zebra/fisiologia , Animais , Comportamento Animal/efeitos dos fármacos , Cálcio/análise , Larva/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Membrana dos Otólitos/efeitos dos fármacos , Fatores de Tempo , Testes de Toxicidade , Transcrição Genética/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/embriologia , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética
11.
Aquat Toxicol ; 214: 105240, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31319295

RESUMO

Fish has a strong resistance to microcystins (MCs), cyclic heptapeptide cyanotoxins, known as endocrine disrupting chemicals (EDCs) which are released during cyanobacterial blooms and many laboratory and field studies have found the hepatic recovery of fish from the MCs exposure. The aim of the present study was to investigate the recovery mechanisms of reproductive function of adult zebrafish (Danio rerio) from microcystin-LR (MC-LR) exposure. Therefore, adult female zebrafish were exposed to 0, 1 or 50 µg/L of MC-LR for 21days and transferred to MC free water for another 21 days to investigate the recovery. After MC-LR exposure, marked histological lesions in the gonads, decreased the percentage of mature oocytes, decreased number of spawned eggs, decreased fertilization and hatching rates were observed. MC-LR exposure increased the concentration of 17ß-estradiol (E2), testosterone (T) and vitellogenin (VTG) in female zebrafish. Some gene transcriptions of the hypothalamic-pituitary-gonad (HPG) axis significantly changed. The protein levels of 17ßhsd and cyp19a remarkably increased in the MC-LR exposure groups. However, our laboratory observation also indicates that zebrafish transferred from microcystin exposure to toxin-free water and reared for 21 days exhibited a nearly complete recovery of reproductive functions, including histological structure, increased the percentage of matured oocytes and spawned eggs, stable hormone levels, well-balanced transcriptional and translational levels. These results indicate that after MC-LR exposure, the reproductive impairments in zebrafish are also reversible likewise hepatic recovery seen by different studies in fish. Future studies should be conducted to explore a better understanding of the recovery mechanisms of fish from microcystins exposure.


Assuntos
Exposição Ambiental , Microcistinas/toxicidade , Reprodução/efeitos dos fármacos , Peixe-Zebra/fisiologia , Animais , Disruptores Endócrinos/toxicidade , Feminino , Hormônios/sangue , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Ovário/citologia , Ovário/efeitos dos fármacos , Ovário/fisiologia , Hipófise/efeitos dos fármacos , Hipófise/metabolismo , Transcrição Genética/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/sangue , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
12.
Aquat Toxicol ; 214: 105257, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31336221

RESUMO

The interactions between nanoparticles (NPs) and metals in aquatic environments may modify the bioavailability and toxicity of metals to organisms. In this study, we investigated the effects of titanium dioxide NPs (n-TiO2) on the bioconcentration, depuration, and neurotoxic effects of lead (Pb) in zebrafish larvae. Transmission electron microscopy coupled with energy-dispersive X-ray spectroscopy showed that Pb2+ was adsorbed by n-TiO2 to form NP-Pb complexes in suspension, and these complexes were observed in larval tissues. The bioconcentration of Pb in larvae along with the depuration rates of Pb were higher in the presence of n-TiO2 compared to when n-TiO2 was absent. Exposure to Pb alone induced the expression of the biomarker metallothionein, downregulated neurodevelopment-related genes, and reduced swimming activity of larvae. However, the addition of n-TiO2 to the exposure solution alleviated these effects. The results suggest that n-TiO2 can act as a carrier of Pb to increase its bioconcentration; however, the formation of NP-Pb complexes likely reduces the amount of free Pb2+, thereby reducing toxicity to larvae.


Assuntos
Chumbo/toxicidade , Nanopartículas/toxicidade , Titânio/toxicidade , Peixe-Zebra/metabolismo , Adsorção , Animais , Comportamento Animal/efeitos dos fármacos , Disponibilidade Biológica , Larva/efeitos dos fármacos , Larva/genética , Larva/ultraestrutura , Locomoção/efeitos dos fármacos , Metalotioneína/metabolismo , Nanopartículas/ultraestrutura , Suspensões , Transcrição Genética/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/genética
13.
Aquat Toxicol ; 214: 105253, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31352076

RESUMO

Diclofop-methyl (DM) is widely used in agriculture and may lead to serious toxicity. However, a limited number of studies have been performed to evaluate the toxicity of DM in the immune and nervous systems of animals. Here, we utilized a good vertebrate model, zebrafish, to evaluate the toxicity of DM during the developmental process. Exposure of zebrafish embryos to 0.1, 0.3 and 0.5 mg/l DM from 6 h post fertilization (hpf) to 72 hpf induced developmental abnormalities, such as shorter body lengths and yolk sac edemas. The number of immune cells in zebrafish larvae was significantly reduced, but the inflammatory response was not influenced by DM treatment. The expression of immune-related genes were downregulated and the levels of oxidative stress were upregulated by DM exposure. Moreover, locomotor behaviors were inhibited by DM exposure. Therefore, our results suggest that DM has the potential to induce immunotoxicity and cause behavioral changes in zebrafish larvae. This study provides new evidence of the influence of DM exposure on aquatic ecosystems.


Assuntos
Comportamento Animal/efeitos dos fármacos , Embrião não Mamífero/imunologia , Exposição Ambiental , Éteres Difenil Halogenados/toxicidade , Peixe-Zebra/embriologia , Animais , Encéfalo/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Larva/efeitos dos fármacos , Larva/metabolismo , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Timócitos/efeitos dos fármacos , Timócitos/metabolismo , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/genética
14.
Ecotoxicol Environ Saf ; 182: 109376, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31254851

RESUMO

Phenanthrene (PHE) is a tricyclic polycyclic aromatic hydrocarbon which distributed extensively in the aquatic environment. However, the knowledge about its impact on fish reproduction is still limited, particularly under a chronic exposure regime. In this study, we exposed zebrafish (Danio rerio) embryos to environmentally relevant concentrations (0.2, 1.0, and 5.0 µg/L) of PHE for 4 months and assessed the impact on reproduction. The results demonstrated that egg production was decreased in fish exposed to PHE, with a significant reduction at 5.0 µg/L. The exposure significantly decreased the circulating concentrations of estradiol (E2) and testosterone (T) in female fish or E2 in male fish. In addition, plasma vitellogenin levels were significantly inhibited after PHE exposure in female fish. The transcription of hypothalamic-pituitary-gonadal (HPG) axis related genes (GnRH2, FSHß, LHß, 17ß-HSD, CYP11A1, and CYP19a) were significantly altered in a sex-specific manner. In addition, embryos derived from exposed parents exhibited increased malformation and decreased hatching success in the F1 generation. Taken together, these results demonstrate that chronic exposure to environmentally relevant concentration of PHE could cause adverse effects on reproduction and impair the development of offspring, ultimately leading to fish population decline in aquatic environment.


Assuntos
Embrião não Mamífero/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Fenantrenos/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/crescimento & desenvolvimento , Animais , Estradiol/sangue , Feminino , Hormônio Liberador de Gonadotropina/sangue , Masculino , Reprodução/efeitos dos fármacos , Fatores Sexuais , Testosterona/sangue , Vitelogeninas/sangue , Peixe-Zebra/sangue , Peixe-Zebra/genética
15.
Aquat Toxicol ; 213: 105219, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31195325

RESUMO

Nrf2 is a crucial transcription factor that regulates the expression of cytoprotective enzymes and controls cellular redox homeostasis. Both arsenic and fluoride are potent toxicants that are known to induce Nrf2. They are reported to coexist in many areas of the world leading to complex mixture effects in exposed organisms. The present study investigated the expression of Nrf2 and related xenobiotic metabolizing enzymes along with other stress markers such as histopathological alterations, catalase activity, reduced glutathione content and lipid peroxidation in zebrafish liver as a function of combined exposure to environmentally relevant concentrations of arsenic (37.87 µgL-1 or 5.05 × 10-7 M) and fluoride (6.8 mg L-1 or 3.57 × 10-4 M) for 60 days. The decrease in the total reduced glutathione level was evident in all treatment conditions. Hyperactivity of catalase along with conspicuous elevation in reactive oxygen species, malondialdehyde content and histo-architectural anomalies signified the presence of oxidative stress in the treatment groups. Nrf2 was seen to be induced at both transcriptional and translational levels in case of both individual and co-exposure. The same pattern was observed in case of its nuclear translocation also. From the results of qRT-PCR it was evident that at each time point co-exposure to arsenic and fluoride seemed to alter the gene expression of Cu/Zn Sod, Mn Sod, Gpx and Nqo1 just like their individual exposure but at a very low magnitude. In conclusion, this study demonstrates for the first time the differential expression and activity of Nrf2 and other stress response genes in the zebrafish liver following individual and combined exposure to arsenic and fluoride.


Assuntos
Arsênico/toxicidade , Fluoretos/toxicidade , Regulação da Expressão Gênica/efeitos dos fármacos , Fígado/enzimologia , Fígado/metabolismo , Fator 2 Relacionado a NF-E2/genética , Xenobióticos/metabolismo , Peixe-Zebra/metabolismo , Animais , Catalase/metabolismo , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Fígado/efeitos dos fármacos , Fígado/patologia , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
16.
Mol Immunol ; 112: 206-214, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31176200

RESUMO

Neutrophil migration is essential for battling against infections but also drives chronic inflammation. Since primary neutrophils are terminally differentiated and not genetically tractable, leukemia cells such as HL-60 are differentiated into neutrophil-like cells to study mechanisms underlying neutrophil migration. However, constitutive overexpression or inhibition in this cell line does not allow the characterization of the genes that affect the differentiation process. Here we apply the tet-on system to induce the expression of a zebrafish microRNA, dre-miR-722, in differentiated HL-60. Overexpression of miR-722 reduced the mRNA level of genes in the chemotaxis and inflammation pathways, including Ras-Related C3 Botulinum Toxin Substrate 2 (RAC2). Consistently, polarization of the actin cytoskeleton, cell migration and generation of the reactive oxygen species are significantly inhibited upon induced miR-722 overexpression. Together, zebrafish miR-722 is a suppressor for migration and signaling in human neutrophil like cells.


Assuntos
Quimiotaxia/genética , MicroRNAs/genética , Neutrófilos/fisiologia , Peixe-Zebra/genética , Actinas/genética , Animais , Diferenciação Celular/genética , Linhagem Celular , Linhagem Celular Tumoral , Movimento Celular/genética , Células HEK293 , Células HL-60 , Humanos , Inflamação/genética , Leucemia/genética , RNA Mensageiro/genética , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/genética , Proteínas de Peixe-Zebra/genética , Proteínas rac de Ligação ao GTP/genética
17.
Ecotoxicol Environ Saf ; 181: 559-571, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31238190

RESUMO

Warfarin is the most worldwide used anticoagulant drug and rodenticide. Since it crosses placental barrier it can induce warfarin embryopathy (WE), a fetal mortality in neonates characterized by skeletal deformities in addition to brain hemorrhages. Although the effects of warfarin exposure in aquatic off target species were already described, the particular molecular toxicological mechanisms during early development are still unclear. Here, we used zebrafish (Danio rerio) to describe and compare the developmental effects of warfarin exposure (0, 15.13, 75.68 and 378.43 mM) on two distinct early developmental phases (embryos and eleuthero-embryos). Although exposure to both developmental phases induced fish mortality, only embryos exposed to the highest warfarin level exhibited features mimicking mammalian WE, e.g. high mortality, higher incidence of hemorrhages and altered skeletal development, among other effects. To gain insights into the toxic mechanisms underlying warfarin exposure, the transcriptome of embryos exposed to warfarin was explored through RNA-Seq and compared to that of control embryos. 766 differentially expressed (564 up- and 202 down-regulated) genes were identified. Gene Ontology analysis revealed particular cellular components (cytoplasm, extracellular matrix, lysosome and vacuole), biological processes (mainly amino acid and lipid metabolism and response to stimulus) and pathways (oxidative stress response and apoptosis signaling pathways) being significantly overrepresented in zebrafish embryos upon warfarin exposure. Protein-protein interaction further evidenced an altered redox system, blood coagulation and vasculogenesis, visual phototransduction and collagen formation upon warfarin exposure. The present study not only describes for the first time the WE in zebrafish, it provides new insights for a better risk assessment, and highlights the need for programming the rat eradication actions outside the fish spawning season to avoid an impact on off target fish community. The urge for the development of more species-specific anticoagulants for rodent pest control is also highlighted.


Assuntos
Anormalidades Induzidas por Medicamentos/metabolismo , Anticoagulantes/toxicidade , Osso Nasal/anormalidades , Rodenticidas/toxicidade , Varfarina/efeitos adversos , Varfarina/toxicidade , Poluentes Químicos da Água/toxicidade , Anormalidades Induzidas por Medicamentos/genética , Animais , Modelos Animais de Doenças , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/metabolismo , Humanos , Osso Nasal/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Transcriptoma , Varfarina/metabolismo , Peixe-Zebra/embriologia , Peixe-Zebra/genética , Peixe-Zebra/metabolismo
18.
PLoS Genet ; 15(6): e1008213, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31199790

RESUMO

The neural crest (NC) is a vertebrate-specific cell type that contributes to a wide range of different tissues across all three germ layers. The gene regulatory network (GRN) responsible for the formation of neural crest is conserved across vertebrates. Central to the induction of the NC GRN are AP-2 and SoxE transcription factors. NC induction robustness is ensured through the ability of some of these transcription factors to compensate loss of function of gene family members. However the gene regulatory events underlying compensation are poorly understood. We have used gene knockout and RNA sequencing strategies to dissect NC induction and compensation in zebrafish. We genetically ablate the NC using double mutants of tfap2a;tfap2c or remove specific subsets of the NC with sox10 and mitfa knockouts and characterise genome-wide gene expression levels across multiple time points. We find that compensation through a single wild-type allele of tfap2c is capable of maintaining early NC induction and differentiation in the absence of tfap2a function, but many target genes have abnormal expression levels and therefore show sensitivity to the reduced tfap2 dosage. This separation of morphological and molecular phenotypes identifies a core set of genes required for early NC development. We also identify the 15 somites stage as the peak of the molecular phenotype which strongly diminishes at 24 hpf even as the morphological phenotype becomes more apparent. Using gene knockouts, we associate previously uncharacterised genes with pigment cell development and establish a role for maternal Hippo signalling in melanocyte differentiation. This work extends and refines the NC GRN while also uncovering the transcriptional basis of genetic compensation via paralogues.


Assuntos
Desenvolvimento Embrionário/genética , Crista Neural/crescimento & desenvolvimento , Fatores de Transcrição SOXE/genética , Fator de Transcrição AP-2/genética , Proteínas de Peixe-Zebra/genética , Animais , Diferenciação Celular/genética , Linhagem da Célula/genética , Embrião não Mamífero , Regulação da Expressão Gênica no Desenvolvimento/genética , Redes Reguladoras de Genes/genética , Melanócitos/metabolismo , Fator de Transcrição Associado à Microftalmia/genética , Crista Neural/metabolismo , Pigmentação/genética , Proteínas Serina-Treonina Quinases/genética , Peixe-Zebra/genética , Peixe-Zebra/crescimento & desenvolvimento
19.
Int J Mol Sci ; 20(9)2019 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-31052497

RESUMO

The purpose of the present study is to evaluate the effect of rice bran ash mineral extract (RBM) on pigmentation in zebrafish (Danio rerio). Melanin has the ability to block ultraviolet (UV) radiation and scavenge free oxygen radicals, thus protecting the skin from their harmful effects. Agents that increase melanin synthesis in melanocytes may reduce the risk of photodamage and skin cancer. The present study investigates the effect of RBM on pigmentation in zebrafish and the underlying mechanism. RBM was found to significantly increase the expression of microphthalmia-associated transcription factor (MITF), a key transcription factor involved in melanin production. RBM also suppressed the phosphorylation of extracellular signal-regulated kinase (ERK), which negatively regulates zebrafish pigmentation. Together, these results suggest that RBM promotes melanin biosynthesis in zebrafish.


Assuntos
Oryza/química , Pigmentação/efeitos dos fármacos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Peixe-Zebra/fisiologia , Animais , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Melaninas/metabolismo , Fator de Transcrição Associado à Microftalmia/genética , Fator de Transcrição Associado à Microftalmia/metabolismo , Fosforilação/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
20.
Fish Shellfish Immunol ; 90: 215-222, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31039438

RESUMO

The zebrafish has unique advantages for understanding the evolution of vertebrate immunity and to model human diseases. In this review, we will firstly give an overview of the current knowledge on vertebrate innate immune receptors with special emphasis on the inflammasome and then summarize the main contribution of the zebrafish model to this field, including to the identification of novel inflammasome components and to the mechanisms involved in its activation, assembly and clearance of intracellular bacteria.


Assuntos
Evolução Biológica , Proteínas de Peixes/genética , Imunidade Inata , Receptores Imunológicos/genética , Peixe-Zebra/imunologia , Animais , Modelos Animais de Doenças , Evolução Molecular , Proteínas de Peixes/metabolismo , Imunidade Inata/genética , Modelos Animais , Receptores Imunológicos/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/metabolismo
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