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2.
Environ Pollut ; 254(Pt A): 112947, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31400664

RESUMO

One of the current main challenges faced by the scientific community is concerning the fate and toxicity of plastics, due to both the well-known threats made by larger plastic items spreading in ecosystems and their fragmentation into micro- and nanoparticles. Since the chemical and physical characteristics of these smaller plastic fragments are markedly different with respect to their bulk product, the potential toxicological effects in the environment need to be deeply investigated. To partially fill this gap of knowledge, the aim of this study was to evaluate the polystyrene nanobead intake in the tissues of zebrafish (Danio rerio) embryos and their related toxicity. Embryos at 72 h post fertilization (hpf) were exposed for 48 h to 0.5 µm fluorescent polystyrene nanobeads at a concentration of 1 mg L-1. Confocal microscopy was employed to investigate nanoplastic ingestion and tissue infiltration, while potential sub-lethal effects were evaluated by measuring several endpoints, which covered the adverse effects at the molecular (protein carbonylation), cellular (P-glycoprotein, activity of several antioxidant/detoxifying enzymes) and organism levels by evaluating of possible changes in the embryos' swimming behaviour. Imaging observations clearly highlighted the nanoplastics' uptake, showing nanobeads not only in the digestive tract, but also migrating to other tissues through the gut epithelium. Biomarker analyses revealed a significant decrease in cyclooxygenase activity and an induction of superoxide dismutase. The behavioural test highlighted a significant (p < 0.05) variation in the turn angle between the control and exposed embryos. This study points out the capability of nanoplastics to infiltrate zebrafish embryo tissues, even after a short exposure, thus suggesting the need for deeper investigations following longer exposure times, and highlighting the potential of nanoplastics to cause toxicological effects on freshwater organisms, at the organism level.


Assuntos
Embrião não Mamífero/metabolismo , Poliestirenos/metabolismo , Poluentes Químicos da Água/metabolismo , Peixe-Zebra/embriologia , Animais , Antioxidantes/farmacologia , Organismos Aquáticos , Ecossistema , Embrião não Mamífero/efeitos dos fármacos , Nanopartículas/química , Plásticos/farmacologia , Poliestirenos/química , Poliestirenos/toxicidade , Superóxido Dismutase , Poluentes Químicos da Água/toxicidade
3.
Ecotoxicol Environ Saf ; 183: 109505, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31394372

RESUMO

Biotests like the fish embryo toxicity test have become increasingly popular in risk assessment and evaluation of chemicals found in the environment. The large range of possible endpoints is a big advantage when researching on the mode of action of a certain substance. Here, we utilized the frequently used model organism zebrafish (Danio rerio) to examine regulative mechanisms in the pathway of the aryl-hydrocarbon receptor (AHR) in early development. We exposed embryos to representatives of two chemical classes known to elicit dioxin-like activity: benzo[a]pyrene for polycyclic aromatic hydrocarbons (PAHs) and 2,3-benzofuran for polar O-substituted heterocycles as a member of heterocyclic compounds in general (N-, S-, O-heterocycles; NSO-hets). We measured gene transcription of the induced P450 cytochromes (cyp1), their formation of protein and biotransformation activity throughout the whole embryonic development until 5 days after fertilization. The results show a very specific time course of transcription depending on the chemical properties (e.g. halogenation, planarity, Kow), the physical decay and the biodegradability of the tested compound. However, although this temporal pattern was not precisely transferable onto the protein level, significant regulation in enzymatic activity over time could be detected. We conclude, that a careful choice of time and end point as well as consideration of the chemical properties of a substance are fairly important when planning, conducting and especially evaluating biotests.


Assuntos
Benzo(a)pireno/toxicidade , Benzofuranos/toxicidade , Receptores de Hidrocarboneto Arílico/metabolismo , Poluentes Químicos da Água/toxicidade , Animais , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/metabolismo , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/metabolismo , Testes de Toxicidade/métodos , Testes de Toxicidade/normas , Transcrição Genética/efeitos dos fármacos , Peixe-Zebra , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
4.
Aquat Toxicol ; 214: 105263, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31376794

RESUMO

The potential toxicity of silver nanoparticles (AgNPs) to the early stages of fish is still unclear. This study used zebrafish embryos as a model to investigate the toxic effects of AgNPs on ion regulation by skin ionocytes. Zebrafish embryos were exposed to AgNPs for 96 h (4-100 h post-fertilization (hpf)) or 4 h (96-100 hpf). After 96 h of exposure to 5 and 10 mg/L AgNPs, survival rates had decreased to 42% and 0%, respectively; the body length had also significantly decreased at 5 mg/L. Whole-body Na+ and K+ contents significantly decreased at 1 and 3 mg/L, while Ca2+ contents decreased at ≥0.1 mg/L. H+ secretion by the skin significantly decreased at 1 mg/L. The density of skin ionocytes labeled with rhodamine 123 (a mitochondrion marker) decreased by 25% and 55% at 1 and 3 mg/L, respectively; and 54% of ionocytes (at 3 mg/L) were deformed from an oval to a spinous shape. After 4 h of exposure to 1 and 5 mg/L, whole-body Na+ and Ca2+ contents, H+ secretion, and density of ionocytes had also significantly decreased. This study revealed the toxicity of AgNPs to skin ionocytes and ion regulation in the early stages of zebrafish embryos.


Assuntos
Embrião não Mamífero/metabolismo , Nanopartículas Metálicas/toxicidade , Prata/toxicidade , Peixe-Zebra/embriologia , Ácidos/metabolismo , Animais , Contagem de Células , Forma Celular/efeitos dos fármacos , Embrião não Mamífero/citologia , Embrião não Mamífero/efeitos dos fármacos , Íons , Larva/efeitos dos fármacos , Análise de Sobrevida , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/anatomia & histologia
5.
Life Sci ; 235: 116791, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31465732

RESUMO

AIMS: Prostate cancer (PCa) incidence rates are rising in China currently. Cancer-associated fibroblasts (CAFs), as a major component of tumor microenvironment, are crucial for tumor progression. This study was aimed to explore the promotion effect of patient-derived CAFs on the proliferation and migration of prostate cancer cells. MAIN METHODS: CAFs were isolated from tumor tissues of PCa patients. The promotion effect of CAFs on the proliferation and migration of PC-3 and LNCaP cells were evaluated in vitro and in vivo. The concentration of TGF-ß1 was measured by Luminex assay. The blocking activity of LY2109761 on the promotion effect of CAFs was also evaluated. KEY FINDINGS: CAFs could significantly promote the proliferation and migration of PC-3 and LNCaP cells both in vitro and in vivo. TGF-ß1 was identified as a highly increased factor in CAFs-CM compared with the normal culture medium of these two cancer cell lines. TGF-ß receptor inhibitor LY2109761 could suppress the CAFs-induced cellular proliferation and migration of PC-3 cells but not LNCaP cells. SIGNIFICANCE: Our study suggested a crucial role for CAFs and TGF-ß signaling in the progression of PCa. Zebrafish xenograft model was an ideal animal model for the study of CAFs and cancer cell interaction.


Assuntos
Fibroblastos Associados a Câncer , Movimento Celular , Proliferação de Células , Embrião não Mamífero/patologia , Neoplasias da Próstata/patologia , Pirazóis/farmacologia , Pirróis/farmacologia , Fator de Crescimento Transformador beta1/metabolismo , Animais , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/antagonistas & inibidores , Transdução de Sinais , Fator de Crescimento Transformador beta1/genética , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto , Peixe-Zebra
6.
Nat Cell Biol ; 21(8): 966-977, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31371827

RESUMO

Migrasomes are recently identified vesicular organelles that form on retraction fibres behind migrating cells. Whether migrasomes are present in vivo and, if so, the function of migrasomes in living organisms is unknown. Here, we show that migrasomes are formed during zebrafish gastrulation and signalling molecules, such as chemokines, are enriched in migrasomes. We further demonstrate that Tspan4 and Tspan7 are required for migrasome formation. Organ morphogenesis is impaired in zebrafish MZtspan4a and MZtspan7 mutants. Mechanistically, migrasomes are enriched on a cavity underneath the embryonic shield where they serve as chemoattractants to ensure the correct positioning of dorsal forerunner cells vegetally next to the embryonic shield, thereby affecting organ morphogenesis. Our study shows that migrasomes are signalling organelles that provide specific biochemical information to coordinate organ morphogenesis.


Assuntos
Embrião não Mamífero/metabolismo , Morfogênese/fisiologia , Organelas/metabolismo , Proteínas de Peixe-Zebra/genética , Animais , Padronização Corporal/fisiologia , Movimento Celular/genética , Movimento Celular/fisiologia , Desenvolvimento Embrionário/fisiologia , Gastrulação/fisiologia , Organelas/genética , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Peixe-Zebra/embriologia
7.
Nat Methods ; 16(8): 750-756, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31363221

RESUMO

The Drosophila wing disc has been a fundamental model system for the discovery of key signaling pathways and for our understanding of developmental processes. However, a complete map of gene expression in this tissue is lacking. To obtain a gene expression atlas in the wing disc, we employed single cell RNA sequencing (scRNA-seq) and developed a method for analyzing scRNA-seq data based on gene expression correlations rather than cell mapping. This enables us to compute expression maps for all detected genes in the wing disc and to discover 824 genes with spatially restricted expression patterns. This approach identifies clusters of genes with similar expression patterns and functional relevance. As proof of concept, we characterize the previously unstudied gene CG5151 and show that it regulates Wnt signaling. Our method will enable the leveraging of scRNA-seq data for generating expression atlases of undifferentiated tissues during development.


Assuntos
Proteínas de Drosophila/genética , Drosophila/genética , Embrião não Mamífero/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Análise de Célula Única/métodos , Asas de Animais/metabolismo , Algoritmos , Animais , Drosophila/embriologia , Embrião não Mamífero/citologia , Feminino , Perfilação da Expressão Gênica , Análise de Sequência de RNA , Asas de Animais/embriologia
8.
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
9.
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
10.
Nat Commun ; 10(1): 2947, 2019 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-31270320

RESUMO

To expand the toolbox of imaging in living cells, we have engineered a single-chain variable fragment binding the linear HA epitope with high affinity and specificity in vivo. The resulting probe, called the HA frankenbody, can light up in multiple colors HA-tagged nuclear, cytoplasmic, membrane, and mitochondrial proteins in diverse cell types. The HA frankenbody also enables state-of-the-art single-molecule experiments in living cells, which we demonstrate by tracking single HA-tagged histones in U2OS cells and single mRNA translation dynamics in both U2OS cells and neurons. Together with the SunTag, we also track two mRNA species simultaneously to demonstrate comparative single-molecule studies of translation can now be done with genetically encoded tools alone. Finally, we use the HA frankenbody to precisely quantify the expression of HA-tagged proteins in developing zebrafish embryos. The versatility of the HA frankenbody makes it a powerful tool for imaging protein dynamics in vivo.


Assuntos
Epitopos/metabolismo , Sondas Moleculares/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Imagem Individual de Molécula , Animais , Linhagem Celular Tumoral , Embrião não Mamífero/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Neurônios/metabolismo , Biossíntese de Proteínas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes de Fusão/isolamento & purificação , Anticorpos de Cadeia Única/metabolismo , Coloração e Rotulagem , Peixe-Zebra/embriologia
11.
Nat Commun ; 10(1): 2951, 2019 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-31273212

RESUMO

Epithelial-mesenchymal transition (EMT) is an essential process both in physiological and pathological contexts. Intriguingly, EMT is often associated with tissue invagination during development; however, the impact of EMT on tissue remodeling remain unexplored. Here, we show that at the initiation of the EMT process, cells produce an apico-basal force, orthogonal to the surface of the epithelium, that constitutes an important driving force for tissue invagination in Drosophila. When EMT is ectopically induced, cells starting their delamination generate an orthogonal force and induce ectopic folding. Similarly, during mesoderm invagination, cells undergoing EMT generate an apico-basal force through the formation of apico-basal structures of myosin II. Using both laser microdissection and in silico physical modelling, we show that mesoderm invagination does not proceed if apico-basal forces are impaired, indicating that they constitute driving forces in the folding process. Altogether, these data reveal the mechanical impact of EMT on morphogenesis.


Assuntos
Drosophila melanogaster/embriologia , Transição Epitelial-Mesenquimal , Epitélio/embriologia , Morfogênese , Animais , Polaridade Celular , Simulação por Computador , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/citologia , Drosophila melanogaster/metabolismo , Embrião não Mamífero/citologia , Embrião não Mamífero/metabolismo , Epitélio/metabolismo , Mesoderma/citologia , Mesoderma/embriologia , Mesoderma/metabolismo , Modelos Moleculares , Miosina Tipo II/metabolismo
12.
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
13.
Chemosphere ; 233: 579-589, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31195263

RESUMO

Complex interactions have been established between nanoparticles (NPs) and heavy metals in real environments. Herein we used zebrafish embryos to investigate the influence of titanium dioxide NPs (n-TiO2) on the uptake, bioconcentration, and depuration, and toxicity of Pb. The formation of n-TiO2-Pb complexes was confirmed in an exposure suspension. An increase in Pb bioconcentration was observed in zebrafish embryos upon co-exposure to n-TiO2 and Pb; moreover, n-TiO2-Pb complexes could be found in the embryos, indicating the bioavailability of NPs. However, there was no difference in the depuration rates of Pb in the presence of n-TiO2. Metallothionein (MT) content was significantly increased upon exposure to Pb alone, and the content significantly increased even further upon co-exposure. A downregulation in the expression levels of the neurodevelopment-related genes gfap, syn2α, and elavl3 was observed in the embryos, and we also noted a reduction in the swimming speed of and the total distance traveled by the larvae. To summarize, our results indicate that n-TiO2 can act as an effective carrier of Pb to enhance its uptake, bioavailability, and toxicity in zebrafish embryos.


Assuntos
Embrião não Mamífero/fisiologia , Chumbo/toxicidade , Nanopartículas Metálicas/toxicidade , Titânio/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/embriologia , Animais , Disponibilidade Biológica , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/metabolismo , Larva/metabolismo , Metalotioneína/metabolismo , Nanopartículas/toxicidade , Peixe-Zebra/metabolismo
14.
Aquat Toxicol ; 213: 105227, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31226596

RESUMO

The environmental impact of exposure to 3D-printed plastics as well as potential migration of toxic chemicals from 3D-printed plastics remains largely unexplored. In this work we applied leachates from plastics fabricated using a stereolithography (SLA) process to early developmental stages of zebrafish (Danio rerio) to investigate developmental toxicity and neurotoxicity. Migration of unpolymerized photoinitiator, 1-hydroxycyclohexyl phenyl ketone (1-HCHPK) from a plastic solid phase to aqueous media at up to 200 mg/L in the first 24 h was detected using gas chromatography-mass spectrometry. Both plastic extracts (LC50 22.25% v/v) and 1-HCHPK (LC50 60 mg/L) induced mortality and teratogenicity within 48 h of exposure. Developmental toxicity correlated with in situ generation of reactive oxygen species (ROS), an increase in lipid peroxidation and protein carbonylation markers and enhanced activity of superoxide dismutase (SOD) and glutathione-S-transferase (GST) in embryos exposed to concentrations as low as 20% v/v for plastic extracts and 16 mg/L for 1-HCHPK. ROS-induced cellular damage led to induction of caspase-dependent apoptosis which could be pharmacologically inhibited with both antioxidant ascorbic acid and a pan-caspase inhibitor. Neuro-behavioral analysis showed that exposure to plastic leachates reduced spontaneous embryonic movement in 24-36 hpf embryos. Plastic extracts in concentrations above 20% v/v induced rapid retardation of locomotion, changes in photomotor response and habituation to photic stimuli with progressive paralysis in 120 hpf larvae. Significantly decreased acetylcholinesterase (AChE) activity with lack of any CNS-specific apoptotic phenotypes as well as lack of changes in motor neuron density, axonal growth, muscle segment integrity or presence of myoseptal defects were detected upon exposure to plastic extracts during embryogenesis. Considering implications of the results for environmental risk assessment and the growing usage of 3D-printing technologies, we speculate that some 3D-printed plastic waste may represent a significant and yet very poorly uncharacterized environmental hazard that merits further investigation on a range of aquatic and terrestrial species.


Assuntos
Comportamento Animal , Sistema Nervoso/efeitos dos fármacos , Plásticos/toxicidade , Impressão Tridimensional , Testes de Toxicidade , Peixe-Zebra/fisiologia , Acetilcolinesterase/metabolismo , Animais , Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , Biomarcadores/metabolismo , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/metabolismo , Desenvolvimento Embrionário/efeitos dos fármacos , Glutationa Transferase/metabolismo , Larva/efeitos dos fármacos , Larva/metabolismo , Neurônios Motores/efeitos dos fármacos , Neurônios Motores/metabolismo , Desenvolvimento Muscular/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/embriologia
15.
Dev Genes Evol ; 229(4): 103-124, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31250106

RESUMO

Many crustacean groups show stereotyped cleavage patterns during early ontogeny. However, these patterns differ between the various major crustacean taxa, and a general mode is difficult to extract. Previous studies suggested that also copepods undergo an early cleavage with a more or less stereotyped pattern of blastomere divisions and fates. Yet, copepod embryology has been largely neglected. The last investigation of this kind dates back more than a century and the results are somewhat contradictory when compared with those of other researchers. To overcome these problems, we studied the early development of a so far undescribed calanoid copepod species, Skistodiaptomus sp., applying histochemical staining, confocal laser scanning microscopy, and bifocal 4D microscopy. The blastomere arrangement of the four-cell stage of this species varies to a large degree. It can either form a typical radial pattern with the four blastomeres lying in one plane or a tilted orientation of the axes connecting the sister cells of the previous division. In both cases, a stereotyped division pattern is maintained inside each quadrant during subsequent cleavages. In addition, we found two types of blastomere arrangements with a mirror symmetry. Most divisions within the quadrants follow the perpendicularity rule until the eighth cleavage. Deviations from this rule occur only in the narrow regions where the different quadrants touch and near the site of gastrulation. Gastrulation is initiated around the descendants of one individually identifiable blastomere of the 16-cell stage. This cell divides in a specific manner forming a characteristic cell arrangement, the gastrulation triangle. This gastrulation triangle initiates the internalization process of the gastrulation and it is encircled by another characteristic cell type, the crown cells. Our observations reveal several similarities to the early development of Calanus finmarchicus, another calanoid species. These relate to blastomere arrangements and divisions and the pattern of gastrulation. As Calanoida represent a basal or near basal branch of the copepod tree, this description will provide the ground for reconstruction of the cleavage pattern of the last common ancestor of Copepoda.


Assuntos
Copépodes/citologia , Copépodes/embriologia , Animais , Blástula/citologia , Blástula/metabolismo , Embrião não Mamífero/citologia , Embrião não Mamífero/metabolismo , Gástrula/citologia , Gástrula/metabolismo
16.
Mar Pollut Bull ; 142: 253-262, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31232302

RESUMO

We used manually spawned, field-deployed embryos of a common marine fish species, Pacific herring (Clupea pallasii), to evaluate accumulation of polycyclic aromatic hydrocarbons (PAHs) associated with an incomplete creosote-treated piling (CTP) removal project. Embryos near undisturbed 100-year-old CTPs (before removal) accumulated higher PAHs and exhibited higher cyp1a gene expression than embryos from reference areas. Embryos incubated close to CTP debris after CTP removal showed PAHs 90 times higher than reference areas up to a year after CTP removal. cyp1a fold-induction correlated with total embryo PAHs in all three years. Patterns of individual PAH chemicals differed slightly between embryos, wood sampled from CTPs, and passive samplers. This study illustrates the importance of using appropriate techniques and procedures to remove CTPs in aquatic environments to prevent release of toxic chemicals. Of particular concern is that incomplete CTP removal could expose sensitive life stages of fishes to chemicals that may reduce their survival.


Assuntos
Creosoto , Peixes/embriologia , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , Animais , Citocromo P-450 CYP1A1/genética , Ecossistema , Ecotoxicologia/métodos , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/metabolismo , Proteínas de Peixes/genética , Peixes/fisiologia , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Washington , Poluentes Químicos da Água/toxicidade , Madeira
17.
Ecotoxicol Environ Saf ; 182: 109377, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31254858

RESUMO

The measurement of oxygen consumption rate (OCR) provides a comprehensive understanding of mitochondrial metabolism. However, no study has been conducted to investigate the mitochondrial dysfunction caused by organophosphate flame retardants (OPFRs). The objectives of this study were to optimize the experimental conditions to measure OCR in zebrafish embryos using the Seahorse XFe 24 Extracellular Flux Analyzer, and to investigate the changes of OCR in zebrafish embryos exposed to OPFRs. We first optimized the experimental conditions such as the number of embryos, concentrations of inhibitors, and time points. We determined the factors, i.e., three embryos, 12.5 µM of oligomycin, 8 µM of carbonyl cyanaide 4-(trifluoromethoxy) phenylhydrazone (FCCP), and 24 hpf (hours post-fertilization) time point, for obtaining the typical pattern of OCR in dechorinated zebrafish embryos. After confirming the determinants upon exposure of triclosan, the inhibition of OCR was measured in zebrafish embryos exposed to two major OPFRs, triphenyl phosphate (TPHP) and tris (1,3-dichloro-2-propyl) phosphate (TDCIPP). We found that significant inhibition of OCR was observed in basal respiration for TPHP, and in basal and maximal respiration for TDCIPP exposure, respectively. We suggest the optimum conditions of the Seahorse XFe 24 analyzer to better evaluate OCR in zebrafish embryos, and demonstrate the potential of TPHP and TDCIPP to cause the disruption of energy metabolism associated with mitochondrial dysfunction.


Assuntos
Embrião não Mamífero/efeitos dos fármacos , Retardadores de Chama/toxicidade , Organofosfatos/toxicidade , Consumo de Oxigênio/efeitos dos fármacos , Peixe-Zebra/metabolismo , Animais , Embrião não Mamífero/metabolismo , Desenvolvimento Embrionário/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Modelos Teóricos
18.
Environ Pollut ; 249: 1049-1059, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31146311

RESUMO

Tebuconazole is a widely used fungicide that has been detected in water ecosystems, of which the concentrations may affect the endocrine function of aquatic organisms. At present study, tissue-specific bioaccumulation of tebuconazole was found in ovary of adult zebrafish, indicating a potential risk of endocrine disruption. In order to evaluate the potential endocrine disrupting effects, three life stages (2 hpf (hours post-fertilization) -60 dpf (days post-fertilization), Stage I; 60-120 dpf, Stage II; 180-208 dpf, Stage III) of zebrafish (Danio rerio) were chronically exposed to tebuconazole at the concentrations ranging from 0.05 mg/L to 1.84 mg/L. Result showed that exposed to tebuconazole could lead to a male-biased sex differentiation in juvenile zebrafish and significant decrease of the percentage of germ cells in sexually-mature zebrafish. Egg production was significantly inhibited by 57.8% and 19.2% after Stage II- and Stage III-exposures, respectively. The contents of 17ß-estradiol in gonad decreased by 63.5% when exposed to 0.20 mg/L tebuconazole at Stage II and by 49.5% after exposed to 0.18 mg/L tebuconazole at Stage III, respectively. For all stages exposure, reductions in 17ß-estradiol/testosterone ratio were observed, indicating an imbalance in steroids synthesis. Additionally, tebuconazole reduced the expression of cyp19a, which was consistent with the decrease of E2 level. In overall, the present findings indicated that, playing as an anti-estrogen-like chemical, tebuconazole inhibited the expression of Cyp19, thereby impairing steroid hormones biosynthesis, leading to a diminished fecundity of zebrafish.


Assuntos
Embrião não Mamífero/efeitos dos fármacos , Disruptores Endócrinos/toxicidade , Fungicidas Industriais/toxicidade , Gônadas/efeitos dos fármacos , Triazóis/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/crescimento & desenvolvimento , Animais , Aromatase/metabolismo , Embrião não Mamífero/metabolismo , Disruptores Endócrinos/metabolismo , Feminino , Fungicidas Industriais/metabolismo , Gônadas/embriologia , Diferenciação Sexual/efeitos dos fármacos , Maturidade Sexual/efeitos dos fármacos , Triazóis/metabolismo , Poluentes Químicos da Água/metabolismo , Peixe-Zebra/metabolismo
19.
Bull Environ Contam Toxicol ; 103(3): 380-384, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31236632

RESUMO

This study compared the concentration of essential (Co, Cr, Cu, Fe, Mn, Ni, Se, Zn) and nonessential (Ag, As, Cd, Hg, Pb) trace elements in the muscle tissue of a pregnant common thresher shark (Alopias vulpinus) to the concentration in the three embryos. With the exception of Ag, Cd, Cr, and Ni which were below the detection limit, all other elements accumulated in the embryo muscle tissue. The Se:Hg molar ratios in the embryos averaged 9.8, indicating that Se may have a protective role against Hg toxicity during this early life stage. Maternal transfer as a source of trace elements in sharks should not be overlooked and future studies need to focus on how reproductive strategy influences this process.


Assuntos
Embrião não Mamífero/metabolismo , Monitoramento Ambiental , Tubarões/embriologia , Oligoelementos/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Feminino , Mercúrio , Músculos/metabolismo , Tubarões/metabolismo
20.
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
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