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1.
Chemosphere ; 254: 126900, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32957295

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous pollutants in marine environments and have arouse great concern since they pose adverse effects to marine ecosystem. To determine the potential impacts of environmentally relevant PAHs on early life stages of marine fish, this study exposed embryos of marine medaka (Oryzias melastigma) to 0, 2, 10, 50, and 250 µg/L of phenanthrene (Phe), one of the most abundant PAHs. The results demonstrated that Phe exposure decreased hatching rates, delayed hatching time of embryos, and increased deformity rate of newly-hatched larvae. Exposure to 10 and 50 µg/L Phe decreased the survival rate of marine medaka larvae at 28 days post-fertilization (dpf), and no embryo successfully hatched in 250 µg/L Phe exposure group. Morphology results showed that 10, 50, and 250 µg/L Phe exposure significantly retarded the development of embryos, and 2, 10, and 50 µg/L caused yolk sac edema and pericardial edema in newly-hatched larvae, indicating that low concentrations of Phe could induce developmental cardiac toxicity. Furthermore, the changes in the expression of heart development-related genes were determined, and the results showed that Phe-induced cardiac malformation might be related with fgf8, bmp4, smyd1, ATPase and gata4 genes. Overall, environmentally relevant PAHs could disrupt heart morphogenesis and hatching process of marine medaka, which might have profound consequences for sustainability of fish population.


Assuntos
Embrião não Mamífero/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Oryzias/crescimento & desenvolvimento , Fenantrenos/toxicidade , Teratogênios/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Ecossistema , Embrião não Mamífero/anormalidades , Desenvolvimento Embrionário/genética , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Coração/efeitos dos fármacos , Coração/embriologia , Larva/efeitos dos fármacos , Larva/genética , Oryzias/genética , Fenantrenos/análise , Teratogênios/análise , Poluentes Químicos da Água/análise
2.
Nat Commun ; 11(1): 4399, 2020 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-32879319

RESUMO

In cnidarians, axial patterning is not restricted to embryogenesis but continues throughout a prolonged life history filled with unpredictable environmental changes. How this developmental capacity copes with fluctuations of food availability and whether it recapitulates embryonic mechanisms remain poorly understood. Here we utilize the tentacles of the sea anemone Nematostella vectensis as an experimental paradigm for developmental patterning across distinct life history stages. By analyzing over 1000 growing polyps, we find that tentacle progression is stereotyped and occurs in a feeding-dependent manner. Using a combination of genetic, cellular and molecular approaches, we demonstrate that the crosstalk between Target of Rapamycin (TOR) and Fibroblast growth factor receptor b (Fgfrb) signaling in ring muscles defines tentacle primordia in fed polyps. Interestingly, Fgfrb-dependent polarized growth is observed in polyp but not embryonic tentacle primordia. These findings show an unexpected plasticity of tentacle development, and link post-embryonic body patterning with food availability.


Assuntos
Padronização Corporal , Anêmonas-do-Mar , Animais , Padronização Corporal/genética , Padronização Corporal/fisiologia , Desenvolvimento Embrionário/efeitos dos fármacos , Comportamento Alimentar , Regulação da Expressão Gênica no Desenvolvimento , Receptores de Fatores de Crescimento de Fibroblastos/genética , Receptores de Fatores de Crescimento de Fibroblastos/metabolismo , Anêmonas-do-Mar/embriologia , Anêmonas-do-Mar/genética , Anêmonas-do-Mar/crescimento & desenvolvimento , Transdução de Sinais , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/metabolismo
3.
Chemosphere ; 258: 127385, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32947675

RESUMO

2,2,4,4-tetrabromodiphenyl ether (BDE-47) has received considerable attention because of its high detection level in biological samples and potential developmental toxicity. Here, using zebrafish (Danio rerio) as the experimental animal, we investigated developmental effects of BDE-47 and explored the potential mechanism. Zebrafish embryos at 4 h post-fertilization (hpf) were exposed to 0.312, 0.625 and 1.25 mg/L BDE-47 to 74-120 hpf. We found that BDE-47 instigated a dose-related developmental toxicity, evidenced by reduced embryonic survival and hatching rate, shortened body length and increased aberration rate. Meanwhile, higher doses of BDE-47 reduced mitochondrial membrane potential and ATP production but increased apoptosis in zebrafish embryos. Expression of genes involved in mitochondrial oxidative phosphorylation (OXPHOS) (ndufb8, sdha, uqcrc1, cox5ab and atp5fal) were negatively related to BDE-47 doses in zebrafish embryos. Moreover, exposure to BDE-47 at 0.625 or 1.25 mg/L impaired mitochondrial biogenesis and mitochondrial dynamics. Our data further showed that BDE- 47 exposure induced excessive reactive oxygen species (ROS) and oxidative stress, which was accompanied by the activation of c-Jun N-terminal Kinase (JNK). Antioxidant NAC and JNK inhibition could mitigate apoptosis in embryos and improve embryonic development in BDE-47-treated zebrafish, suggesting the involvement of ROS/JNK pathway in embryonic developmental changes induced by BDE-47. Altogether, our data suggest here that developmental toxicity of BDE-47 may be associated with mitochondrial ROS-mediated JNK signaling in zebrafish embryo.


Assuntos
Éteres Difenil Halogenados/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Embrião não Mamífero/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases , Mitocôndrias/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Peixe-Zebra/metabolismo
4.
Ecotoxicol Environ Saf ; 203: 110934, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32888599

RESUMO

Pharmaceuticals and personal care products are emerging contaminants that are increasingly detected in the environment worldwide. Certain classes of pharmaceuticals, such as selective serotonin reuptake inhibitors (SSRIs), are a major environmental concern due to their widespread use and the fact that these compounds are designed to have biological effects at low doses. A complication in predicting toxic effects of SSRIs in nontarget organisms is that their mechanism of action is not fully understood. To better understand the potential toxic effects of SSRIs, we employed an ultra-low input RNA-sequencing method to identify potential pathways that are affected by early exposure to two SSRIs (fluoxetine and paroxetine). We exposed wildtype zebrafish (Danio rerio) embryos to 100 µg/L of either fluoxetine or paroxetine for 6 days before extracting and sequencing mRNA from individual larval brains. Differential gene expression analysis identified 1550 genes that were significantly affected by SSRI exposure with a core set of 138 genes altered by both SSRIs. Weighted gene co-expression network analysis identified 7 modules of genes whose expression patterns were significantly correlated with SSRI exposure. Functional enrichment analysis of differentially expressed genes as well as network module genes repeatedly identified various terms associated with mitochondrial and neuronal structures, mitochondrial respiration, and neurodevelopmental processes. The enrichment of these terms indicates that toxic effects of SSRI exposure are likely caused by mitochondrial dysfunction and subsequent neurodevelopmental effects. To our knowledge, this is the first effort to study the tissue-specific transcriptomic effects of SSRIs in developing zebrafish, providing specific, high resolution molecular data regarding the sublethal effects of SSRI exposure.


Assuntos
Encéfalo/efeitos dos fármacos , Larva/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Inibidores de Captação de Serotonina/toxicidade , Transcriptoma/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Peixe-Zebra , Animais , Encéfalo/embriologia , Biologia Computacional , Embrião não Mamífero/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Humanos , Larva/genética , Análise de Sequência de RNA , Peixe-Zebra/genética
5.
Ecotoxicol Environ Saf ; 202: 110922, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32800257

RESUMO

Fluorene-9-bisphenol (BHPF) is a substitute for bisphenol A (BPA), which is widely used to manufacture plastic products. Previous studies indicate that BHPF has an anti-estrogenic effect and induces cytotoxicity in mice oocytes. However, the effects of acute BHPF exposure on the aquatic organism obtain little attention. In this study, a series of BHPF concentrations (1 µM, 2 µM, 5 µM, 10 µM, 20 µM) was used to exposed zebrafish embryos from 2 h post-fertilization (hpf). The results showed the LC50 at 96hpf was 2.88 µM (1.01 mg/L). Acute exposure induced malformation in morphology, and retarded epiboly rate at 10hpf, increased apoptosis. Moreover, acute BHPF exposure led cardiotoxicity, by impeding cardiac looping, decreasing cardiac contractility (reducing the stroke volume and cardiac output, decreasing fractional shortening of ventricle). Besides that, BHPF exposure altered the expression of cardiac transcriptional regulators and development related genes. In conclusion, acute BHPF exposure induced developmental abnormality, retarded cardiac morphogenesis and injured the cardiac contractility. This study indicated BHPF would be an unneglected threat for the safety of aquatic organisms.


Assuntos
Compostos Benzidrílicos/toxicidade , Fenóis/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Cardiotoxicidade/metabolismo , Embrião não Mamífero/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Fluorenos/toxicidade , Camundongos , Oócitos/crescimento & desenvolvimento , Plásticos , Testes de Toxicidade Aguda , Poluentes Químicos da Água/metabolismo , Peixe-Zebra
6.
Ecotoxicol Environ Saf ; 204: 111068, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32745784

RESUMO

Herein, eight common endocrine disrupting chemicals (EDCs) were exposed to zebrafish (Danio rerio) to investigate the relationship between different EDCs and their activated estrogen receptors. Under acute exposure, we identified five major malformation types whose incidence and deformity modes differed among EDCs. Luciferase analysis divided the EDC receptors into four categories: (i) triclosan (TCS), 17ß-estradiol (E2) and estriol (E3) mainly activated GPER expression; (ii) bisphenol A (BPA), p-(tert-octyl) phenol (POP), 17α-ethynylestradiol (EE2), E2 and E3 activated ERß expression; (iii) E2 and E3 acted on both GPER and ERß; and (iv) estrone (E1) and 9,9-bis(4-hydroxyphenyl)fluorene (BHPF) had little effect on the two receptors. In vivo immunofluorescence experiments on 96-hpf larvae provided evidence that TCS and POP acted on GPER and ERß, respectively, while E2 acted on the two receptors simultaneously. Luciferase activities in the promoter regions of gper (-986 to -488) and erß (-1998 to -1496) were higher than those in other regions, identifying these key regions as targets for transcription activity. TCS promoted GPER expression by acting on the JUND transcription factor, while POP promoted ERß expression by activating the Foxl1 transcription factor. In contrast, E2 mainly regulated transcription of GPER and ERß by Arid3a. These findings provide compelling evidence that different EDCs possess varying estrogen receptors, leading to differential regulatory pathways and abnormality symptoms. These results offer an experimental strategy and fundamental information to assess the molecular mechanisms of EDC-induced estrogen effects.


Assuntos
Compostos Benzidrílicos/toxicidade , Disruptores Endócrinos/toxicidade , Receptor beta de Estrogênio/metabolismo , Fenóis/toxicidade , Receptores Acoplados a Proteínas-G/metabolismo , Poluentes Químicos da Água/toxicidade , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/metabolismo , Animais , Compostos Benzidrílicos/metabolismo , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/metabolismo , Desenvolvimento Embrionário/efeitos dos fármacos , Disruptores Endócrinos/metabolismo , Larva/efeitos dos fármacos , Larva/metabolismo , Fenóis/metabolismo , Poluentes Químicos da Água/metabolismo
7.
PLoS One ; 15(7): e0223633, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32701951

RESUMO

BACKGROUND: Small conductance, calcium-activated (SK3) potassium channels control the intrinsic excitability of dopaminergic neurons (DN) in the midbrain and modulate their susceptibility to toxic insults during development. METHODS: We evaluated the age-dependency of the neuroprotective effect of an SK3 agonist, 1-Ethyl-1,3-dihydro-2H-benzimidazol-2-one (1-EBIO), on Amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) excitotoxicity to DN in ventral mesencephalon (VM) organotypic cultures. RESULTS: Most tyrosine hydroxylase (TH)+ neurons were also SK3+; SK3+/TH- cells (DN+) were common at each developmental stage but more prominently at day in vitro (DIV) 8. Young DN+ neurons were small bipolar and fusiform, whereas mature ones were large and multipolar. Exposure of organotypic cultures to AMPA (100 µm, 16 h) had no effect on the survival of DN+ at DIV 8, but caused significant toxicity at DIV 15 (n = 15, p = 0.005) and DIV 22 (n = 15, p<0.001). These results indicate that susceptibility of DN to AMPA excitotoxicity is developmental stage-dependent in embryonic VM organotypic cultures. Immature DN+ (small, bipolar) were increased after AMPA (100 µm, 16 h) at DIV 8, at the expense of the number of differentiated (large, multipolar) DN+ (p = 0.039). This effect was larger at DIV 15 (p<<<0.0001) and at DIV 22 (p<<<0.0001). At DIV 8, 30 µM 1-EBIO resulted in a large increase in DN+. At DIV 15, AMPA toxicity was prevented by exposure to 30 µM, but not 100 µM 1-EBIO. At DIV 22, excitotoxicity was unaffected by 30 µM 1-EBIO, and partially reduced by 100 µM 1-EBIO. CONCLUSION: The effects of the SK3 channel agonist 1-EBIO on the survival of SK3-expressing dopaminergic neurons were concentration-dependent and influenced by neuronal developmental stage.


Assuntos
Neurônios Dopaminérgicos/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Canais de Potássio Ativados por Cálcio de Condutância Baixa/agonistas , Animais , Benzimidazóis/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/patologia , Embrião de Mamíferos/citologia , Desenvolvimento Embrionário/efeitos dos fármacos , Feminino , Mesencéfalo/citologia , Mesencéfalo/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de AMPA/metabolismo , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico/toxicidade
8.
Aquat Toxicol ; 226: 105560, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32659603

RESUMO

Triclosan (TCS) is commonly used in home and personal care products (HPCPs), which causes it to be ubiquitously detected in aquatic environments. The toxicity of triclosan to aquatic organisms can vary at different pH values because the ionization states of TCS affect its bioaccumulation properties. The objective of this study was to examine the pH-dependent toxicity of TCS on embryonic zebrafish (Danio rerio) using a metabolomic profiling method based on gas chromatography-mass spectrometry (GC-MS). Exposure experiments were conducted on zebrafish embryos at three pH conditions (6, 7, and 8) and two TCS concentrations (30 µg/L and 300 µg/L). Metabolic profiles were obtained by extracting intracellular metabolites. Univariate (One-way ANOVA) and multivariate (PLS-DA) analyses were conducted to determine the metabolomic changes in TCS-treated embryos. Changes in the metabolic profile revealed that interference in biological pathways were induced by mostly ionized TCS (low pH) and high TCS concentrations. Also, fold changes in metabolite profiles showed that the TCS toxicity was a function of pH. Metabolites including urea, D-glucose, D-galactose, phenylalanine, L-glutamic acid, citric acid, and phosphoric acid showed significant changes under different pH conditions (p-value < 0.05). Our metabolomics study revealed that the responses of metabolites to TCS toxicity were pH-dependent. The differences of the responses could be attributed to the bioaccumulation capability of TCS, which increased as the ionized TCS proportion increased under low pH conditions.


Assuntos
Embrião não Mamífero/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Metaboloma/efeitos dos fármacos , Triclosan/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/metabolismo , Animais , Embrião não Mamífero/metabolismo , Concentração de Íons de Hidrogênio , Metabolômica/métodos , Peixe-Zebra/crescimento & desenvolvimento
9.
Aquat Toxicol ; 226: 105562, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32668346

RESUMO

Fish are exposed to steroids of different classes in contaminated waters, but their effects are not sufficiently understood. Here we employed an anti-sense technique using morpholino oligonucleotides to knockdown the glucocorticoid receptors (GRs, GRα and GRß) and androgen receptor (AR) to investigate their role in physiological and transcriptional responses. To this end, zebrafish embryos were exposed to clobetasol propionate (CLO), androstenedione (A4) and mixtures containing different classes of steroids. CLO caused a decrease of spontaneous muscle contraction and increase of heart rate, as well as transcriptional induction of pepck1, fkbp5, sult2st3 and vitellogenin (vtg1) at 24 and/or 48 h post fertilization (hpf). Knockdown of GRs eliminated these effects, while knockdown of AR decreased the ar transcript but caused no expressional changes, except induction of sult2st3 after exposure to A4 at 24 hpf. Exposure to a mixture of 6 steroids comprising progesterone (P4) and three progestins, cyproterone acetate, dienogest, drospirenone, 17ß-estradiol (E2) and CLO caused a significant induction of pepck1, sult2st3, vtg1 and per1a. Knockdown of GRs eliminated the physiological effects and the up-regulation of vtg1, sult2st3, pepck1, fkbp5 and per1a. Thus, as with CLO, responses in mixtures were regulated by GRs independently from the presence of other steroids. Exposure to a mixture comprising A4, CLO, E2 and P4 caused induction of vtg1, cyp19b, sult2st3 and fkbp5. Knockdown of AR had no effect, indicating that regulation of these genes occurred by the GRs and estrogen receptor (ER). Our findings show that in early embryos GRs cause vtg1 and sult2st3 induction in addition to known glucocorticoid target genes. Each steroid receptor regulated its own target genes in steroid mixtures independently from other steroids. However, enhanced expressional induction occurred for vtg1 and fkbp5 in steroid mixtures, indicating an interaction/cross-talk between GRs and ER. These findings have importance for the understanding of molecular effects of steroid mixtures.


Assuntos
Embrião não Mamífero/efeitos dos fármacos , Receptores Androgênicos/metabolismo , Receptores de Glucocorticoides/metabolismo , Esteroides/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/metabolismo , Animais , Embrião não Mamífero/metabolismo , Desenvolvimento Embrionário/efeitos dos fármacos , Desenvolvimento Embrionário/genética , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Receptores Androgênicos/genética , Receptores de Glucocorticoides/genética , Transdução de Sinais , Peixe-Zebra/genética , Peixe-Zebra/crescimento & desenvolvimento
10.
Chemosphere ; 259: 127380, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32634720

RESUMO

Fomesafen is widely used in agriculture and can be detected in the environment and agricultural products. Research on the developmental toxicity of fomesafen in animals is currently very limited. Here, we used zebrafish as an animal model to evaluate the toxicity of fomesafen in developing aquatic vertebrates and higher animals. From 6h to 72h following fertilization, exposure of zebrafish embryos to 5, 10 and 20 mg/L of fomesafen resulted in pericardial edema, a reduction in heart rate, shortening of body length, and yolk sac edema. Fomesafen reduced the number of immune cells such as neutrophils and macrophages, increased the expression of a number of inflammatory factors, induced the up-regulation of the oxidative stress response and apoptosis, and disrupted the activity of enzymes related to nerve development, which affected the motility of the embryos. In conclusion, the results provide new evidence for the comprehensive assessment of fomesafen toxicity in aquatic vertebrates.


Assuntos
Benzamidas/toxicidade , Embrião não Mamífero/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Herbicidas/toxicidade , Animais , Apoptose/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Regulação para Cima , Peixe-Zebra/embriologia , Peixe-Zebra/metabolismo
11.
PLoS One ; 15(7): e0235617, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32634160

RESUMO

Low egg quality and embryonic survival are critical challenges in aquaculture, where assisted reproduction procedures and other factors may impact egg quality. This includes European eel (Anguilla anguilla), where pituitary extract from carp (CPE) or salmon (SPE) is applied to override a dopaminergic inhibition of the neuroendocrine system, preventing gonadotropin secretion and gonadal development. The present study used either CPE or SPE to induce vitellogenesis in female European eel and compared impacts on egg quality and offspring developmental competence with emphasis on the maternal-to-zygotic transition (MZT). Females treated with SPE produced significantly higher proportions of floating eggs with fewer cleavage abnormalities and higher embryonic survival. These findings related successful embryogenesis to higher abundance of mRNA transcripts of genes involved in cell adhesion, activation of MZT, and immune response (dcbld1, epcam, oct4, igm) throughout embryonic development. The abundance of mRNA transcripts of cldnd, foxr1, cea, ccna1, ccnb1, ccnb2, zar1, oct4, and npm2 was relatively stable during the first eight hours, followed by a drop during MZT and low levels thereafter, indicating transfer and subsequent clearance of maternal mRNA. mRNA abundance of zar1, epcam, and dicer1 was associated with cleavage abnormalities, while mRNA abundance of zar1, sox2, foxr1, cldnd, phb2, neurod4, and neurog1 (before MZT) was associated with subsequent embryonic survival. In a second pattern, low initial mRNA abundance with an increase during MZT and higher levels persisting thereafter indicating the activation of zygotic transcription. mRNA abundance of ccna1, npm2, oct4, neurod4, and neurog1 during later embryonic development was associated with hatch success. A deviating pattern was observed for dcbld1, which mRNA levels followed the maternal-effect gene pattern but only for embryos from SPE treated females. Together, the differences in offspring production and performance reported in this study show that PE composition impacts egg quality and embryogenesis and in particular, the transition from initial maternal transcripts to zygotic transcription.


Assuntos
Anguilla/fisiologia , Carpas/metabolismo , Desenvolvimento Embrionário , Oogênese , Hipófise/metabolismo , Salmão/metabolismo , Anguilla/crescimento & desenvolvimento , Animais , Ciclina A1/genética , Desenvolvimento Embrionário/efeitos dos fármacos , Desenvolvimento Embrionário/genética , Feminino , Proteínas de Peixes/genética , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Fator 3 de Transcrição de Octâmero/genética , Oogênese/efeitos dos fármacos , Hipófise/química , Hormônios Hipofisários/farmacologia , RNA Mensageiro/metabolismo , Zigoto/efeitos dos fármacos , Zigoto/crescimento & desenvolvimento , Zigoto/metabolismo
12.
Artigo em Inglês | MEDLINE | ID: mdl-32617729

RESUMO

Some species of fish have been used as bioindicators of aquatic environmental pollution all over the world. Pejerrey (Odontesthes bonariensis) was selected for the current study due to its sensitivity to pollutants and because is one of the emblematic fish species that inhabits shallow lakes of the Pampa region (Argentina). Recently, in Chascomús lake were recorded concentrations of Cd, Cr, Cu and Zn with values above the Argentine National Guidelines for the Protection of the Aquatic life. Regarding this, the aim of the present study was to investigate the effects of environmental concentrations of these metals on the sperm quality, fertilization and hatching rates, and embryo and larval survival of pejerrey. Also, the same endpoints were analyzed with concentrations ten times higher to simulate a polluted worst-case scenario. The results showed that the presence of some metals in aquatic environments reduced pejerrey sperm motility (in ~50%) and velocity (in ~30%). These results were obtained using a computer assisted sperm analyzer enforcing the application of this analysis as a tool or bioindicator of aquatic pollution. In addition, fertilization rate was diminished (in ~40%) for all treatments. Besides, the hatching rate, and embryo and larval survival were drastically affected being zero for the highest metal concentrations assessed. All together these results, showed that even lower metal concentrations can negatively affect different reproductive parameters of one of the most emblematic fish species of the Argentinean water bodies.


Assuntos
Embrião não Mamífero/efeitos dos fármacos , Fertilização/efeitos dos fármacos , Metais Pesados/efeitos adversos , Smegmamorpha/fisiologia , Espermatozoides/efeitos dos fármacos , Poluentes Químicos da Água/efeitos adversos , Animais , Desenvolvimento Embrionário/efeitos dos fármacos , Longevidade/efeitos dos fármacos , Masculino , Análise do Sêmen/veterinária
13.
Toxicol Lett ; 331: 124-129, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32534006

RESUMO

DNA damage quantified as the comet tail length was assessed using in vitro and in vivo comet assay on one- and two-cell mouse embryos obtained by natural mating. The use of a protocol with three layers of agarose reduces the embryo loss and makes it possible to study a small number of embryos. A significantly lower level of basal, but not induced DNA damage was found in embryos with cleaved zona pellucida compared to embryos with intact zona pellucida. There were no significant differences in the length of the comet's tail between embryos lysed in different lysis solutions, both in cases of basal and induced DNA damage. A significant increase in the comet tail length was detected in one-cell embryos of mice treated with methyl methanesulfonate and etoposide compared to the control. The data show that DNA damage induced in maternal germ cells persists, which can be detected in embryos using the comet assay.


Assuntos
Dano ao DNA , Embrião de Mamíferos/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Mutagênicos/toxicidade , Zona Pelúcida/efeitos dos fármacos , Animais , Ensaio Cometa , Embrião de Mamíferos/patologia , Desenvolvimento Embrionário/genética , Feminino , Masculino , Exposição Materna , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Gravidez , Zona Pelúcida/patologia
14.
Ecotoxicol Environ Saf ; 201: 110826, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32521368

RESUMO

As an effective feed additive in the livestock industry, olaquindox (OLA) has been widely used in domestic animal production. However, it is unclear whether OLA has negative effects on mammalian oocyte quality and fetal development. In this study, toxic effects of OLA were tested by intragastric gavage ICR mice with water, low-dose OLA (5 mg/kg/day), or high-dose OLA (60 mg/kg/day) for continuous 45 days. Results showed that high-dose OLA gavage severely affected the offspring birth and growth. Significantly, high-dose OLA impaired oocyte maturation and early embryo development, indicated by the decreased percentage of germinal vesicle breakdown, first polar body extrusion and blastocyst formation. Meanwhile, oxidative stress levels were increased in oocytes or ovaries, indexed by the increased levels of ROS, MDA, H2O2, NO, and decreased levels of GSH, SOD, CAT, GSH-Px and GSH-Rd. Furthermore, aberrant mitochondria distribution, defective spindle assembly, abnormal H3K4me2/H3K9me3 levels, increased DNA double-strand breaks and early apoptosis rate, were observed after high-dose OLA gavage. Taken together, our results for the first time illustrated that high-dose OLA gavage led to sub-fertility of females, which means that restricted utilization of OLA as feed additive should be considered.


Assuntos
Desenvolvimento Embrionário/efeitos dos fármacos , Aditivos Alimentares/toxicidade , Oócitos/efeitos dos fármacos , Oogênese/efeitos dos fármacos , Quinoxalinas/toxicidade , Administração Oral , Animais , Apoptose/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Peróxido de Hidrogênio/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Mitocôndrias/efeitos dos fármacos , Oócitos/metabolismo , Oócitos/patologia , Ovário/efeitos dos fármacos , Ovário/metabolismo , Oxirredução , Estresse Oxidativo/efeitos dos fármacos
15.
PLoS One ; 15(6): e0233880, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32497112

RESUMO

The efficiency of somatic cell nuclear transfer (SCNT) is low due to the strong resistance of somatic donor cells to epigenetic reprogramming. Many epigenetic drugs targeting DNA methylation and histone acetylation have been used in attempts to improve the in vitro and in vivo development of SCNT embryos. H3K9me3 has been shown to be an important reprogramming barrier for generating induced pluripotent stem cells (iPSCs) and SCNT embryos in mice and humans. In this study, we examined the effects of selective siRNA and chemical inhibition of H3K9me3 in somatic donor cells on the in vitro development of bovine SCNT embryos. Chaetocin, an inhibitor of SUV39H1/H2, was supplemented during the culture of donor cells. In addition, the siRNA knockdown of SUV39H1/H2 was performed in the donor cells. The effects of chaetocin and siSUV39H1/H2 on H3K9me3 and H3K9ac were quantified using flow cytometry. Furthermore, we assessed chaetocin treatment and SUV39H1/H2 knockdown on the blastocyst formation rate. Both chaetocin and siSUV39H1/H2 significantly reduced and elevated the relative intensity level of H3K9me3 and H3K9ac in treated fibroblast cells, respectively. siSUV39H1/H2 transfection, but not chaetocin treatment, improved the in vitro development of SCNT embryos. Moreover, siSUV39H1/H2 altered the expression profile of the selected genes in the derived blastocysts, similar to those derived from in vitro fertilization (IVF). In conclusion, our results demonstrated H3K9me3 as an epigenetic barrier in the reprogramming process mediated by SCNT in bovine species, a finding which supports the role of H3K9me3 as a reprogramming barrier in mammalian species. Our findings provide a promising approach for improving the efficiency of mammalian cloning for agricultural and biomedical purposes.


Assuntos
Bovinos/embriologia , Desenvolvimento Embrionário , Histona-Lisina N-Metiltransferase/genética , Técnicas de Transferência Nuclear , Proteínas Repressoras/genética , Animais , Bovinos/genética , Bovinos/metabolismo , Células Cultivadas , Desenvolvimento Embrionário/efeitos dos fármacos , Epigênese Genética , Feminino , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Histona-Lisina N-Metiltransferase/antagonistas & inibidores , Histonas/genética , Histonas/metabolismo , Interferência de RNA , RNA Interferente Pequeno/genética , Proteínas Repressoras/antagonistas & inibidores
16.
Aquat Toxicol ; 225: 105540, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32569997

RESUMO

The zebrafish (Danio rerio) embryo has increasingly been used as an alternative model in human and environmental toxicology. Since the cytochrome P450 (CYP) system is of fundamental importance for the understanding and correct interpretation of the outcome of toxicological studies, constitutive and xenobiotic-induced 7-methoxycoumarin-O-demethylase (MCOD), i.e. 'mammalian CYP2-like', activities were monitored in vivo in zebrafish embryos via confocal laser scanning microscopy. In order to elucidate molecular mechanisms underlying the MCOD induction, dose-dependent effects of the prototypical CYP inducers ß-naphthoflavone (aryl hydrocarbon receptor (AhR) agonist), rifampicin (pregnane X receptor (PXR) agonist), carbamazepine and phenobarbital (constitutive androstane receptor (CAR) agonists) were analyzed in zebrafish embryos of varying age. Starting from 36 h of age, all embryonic stages of zebrafish could be shown to have constitutive MCOD activity, albeit with spatial variation and at distinct levels. Whereas carbamazepine, phenobarbital and rifampicin had no effect on in vivo MCOD activity in 96 h old zebrafish embryos, the model aryl hydrocarbon receptor agonist ß-naphthoflavone significantly induced MCOD activity in 96 h old zebrafish embryos at 46-734 nM, however, without a clear concentration-effect relationship. Induction of MCOD activity by ß-naphthoflavone gradually decreased with progression of embryonic development. By in vivo characterization of constitutive and xenobiotic-induced MCOD activity patterns in 36, 60, 84 and 108 h old zebrafish embryos, this decrease could primarily be attributed to an age-related decline in the induction of MCOD activity in the cardiovascular system. Results of this study provide novel insights into the mechanism and extent, by which specific CYP activities in early life-stages of zebrafish can be influenced by exposure to xenobiotics. The study thus lends further support to the view that zebrafish embryos- at least from an age of 36 h - have an elaborate and inducible biotransformation system.


Assuntos
Sistema Enzimático do Citocromo P-450/biossíntese , Embrião não Mamífero/efeitos dos fármacos , Oxirredutases O-Desmetilantes/biossíntese , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/metabolismo , Animais , Biotransformação , Indutores das Enzimas do Citocromo P-450/toxicidade , Embrião não Mamífero/enzimologia , Desenvolvimento Embrionário/efeitos dos fármacos , Receptores de Hidrocarboneto Arílico/metabolismo , Xenobióticos/toxicidade , Proteínas de Peixe-Zebra/metabolismo , beta-Naftoflavona/toxicidade
17.
Ecotoxicol Environ Saf ; 201: 110725, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32474209

RESUMO

Lincomycin hydrochloride is one of the commonly used drugs in clinic. However, it has many side effects on patients, and its mechanism is still poorly understood. In this study, 6 h post-fertilization (6 hpf) zebrafish embryos were exposed to several concentrations of lincomycin hydrochloride (15, 30, 60 µg/mL) for up to 24 or 96 hpf to detect their developmental toxicity and neurotoxicity, and to 6 days post-fertilization (6 dpf) to detect their behavioral toxicity. Our results showed that lincomycin hydrochloride could lead to embryonic head deformities (unclear ventricles, smaller ventricles, fewer new neurons). The studies showed that the frequency of spontaneous tail flick of zebrafish embryo increased at 24 hpf, and the lincomycin hydrochloride exposed zebrafish embryos showed increased heart rate, shorter body length, and yolk sac edema with severe pericardial edema at 96 hpf. The studies also showed that lincomycin hydrochloride increased oxidative stress level, Acetylcholinesterase (AChE) activity, ATPase activity and apoptosis in zebrafish larvae. In addition, the swimming behavior of zebrafish larvae decreased with the increase of lincomycin hydrochloride concentration, but the angular velocity and meandering degree increased, which might be due to the decreased activity of AChE and ATPase, as well as the decreased expression of genes related to neurodevelopment and neurotransmitter system, leading to the change of their motor behaviors. In summary, we found that lincomycin hydrochloride induced developmental toxicity and neurotoxicity in zebrafish larvae, contributing to a more comprehensive evaluation of the safety of the drug.


Assuntos
Lincomicina/toxicidade , Síndromes Neurotóxicas/etiologia , Acetilcolinesterase/metabolismo , Adenosina Trifosfatases/metabolismo , Animais , Apoptose/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Síndromes Neurotóxicas/congênito , Estresse Oxidativo/efeitos dos fármacos , Peixe-Zebra
18.
Parasitol Res ; 119(10): 3369-3376, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32556502

RESUMO

Toxocara canis is a common parasite of dogs and can cause zoonotic toxocariasis in humans. As a part of control programs for this agent, optimized hygiene including chemical disinfection is considered essential in the prevention and control of zoonotic toxocariasis in humans. However, commonly used disinfectants at present mostly fail to inhibit the embryogenesis and viability of T. canis eggs. To this effect, the present study was designed to evaluate the effect of a chlorocresol-based disinfectant product Neopredisan®135-1 (NP) on embryonic development of T. canis eggs in vitro and to investigate the infectivity of exposed eggs by assessing larval establishment in a mouse model. Under in vitro conditions, NP at a final concentration of 0.25, 0.50, 1, 2, or 4% all exhibited significant killing effect on T. canis embryogenesis compared with the control eggs (P < 0.05), regardless of contact times (30, 60, 90, or 120 min). Such killing activity increased in a concentration- and time-dependent manner, with a maximum killing efficacy of 95.81% at 4% concentration and 120 min exposure time. Comparisons between low and high concentrations and between short and long contact times concluded that a protocol using the 1% concentration of NP with a 90-min contact could be the most suitable for practical application. Additionally, the lower larval recovery in mice inoculated with eggs treated by either 0.25 or 0.5% NP than that from their corresponding controls (P < 0.05) verified once again that NP had an adverse impact on the larval development of T. canis eggs even at a low concentration. To the best of our knowledge, this is the first study to report the effect of the chlorocresol-based disinfectant NP on the embryonation and larval development of T. canis eggs, and the results presented here would contribute to environmental clearance and control of toxocariasis by providing an alternative disinfectant resource. However, it is highlighted that the clearance of the novel and existing sources of infection including larvated eggs in places treated with NP is not guaranteed and therefore continuous monitoring and additional disinfection are still required.


Assuntos
Antinematódeos/farmacologia , Cresóis/farmacologia , Desinfetantes/farmacologia , Toxocara canis/efeitos dos fármacos , Toxocaríase/prevenção & controle , Animais , Desenvolvimento Embrionário/efeitos dos fármacos , Feminino , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Camundongos , Óvulo/efeitos dos fármacos , Óvulo/crescimento & desenvolvimento , Carga Parasitária , Toxocara canis/crescimento & desenvolvimento , Toxocaríase/parasitologia
19.
PLoS One ; 15(6): e0235140, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32574203

RESUMO

BACKGROUND: Due to improved treatment, there is an increasing focus on the reproductive potential of survivors of childhood cancer. Cytotoxic chemotherapy accelerates the decline in the number of primordial follicles within the mammalian ovary at all ages, but effects on the developmental potential of remaining oocytes following prepubertal cancer treatment are unclear. OBJECTIVES: To investigate whether cyclophosphamide (CY) exposure in the prepubertal period in female mice influences ovarian function and the functional competence of oocytes in adulthood. METHODS: This study used Swiss albino mice as the experimental model. Female mice were treated with 200 mg/kg CY on either postnatal day 14 (CY14), 21 (CY21) or 28 (CY28) i.e at a prepubertal and 2 young postpubertal ages. At 14 weeks of life, ovarian function, functional competence of oocytes, and embryo quality were assessed. RESULTS: The number of primordial follicles decreased significantly in CY14 and CY21 groups compared to control (p < 0.01). The number of oocytes from superovulated was 8.5 ± 1.4, 24.1 ± 2.9 and 26.8 ± 2.1 in CY14, CY21 and CY28 respectively which was significantly lower than control (50.2 ± 3.2; p < 0.001). In vitro culture of CY14 embryos demonstrated only 55.4% blastocyst formation (p < 0.0001) and reduced ability of inner cell mass (ICM) to proliferate in vitro (p < 0.05) at 120 and 216 h post insemination respectively. On the other hand, ICM proliferation was unaltered in 2 young postpubertal ages. CONCLUSION: Our results indicate long-term effects on the developmental competence of oocytes exposed to CY in early but not adult life. These data provide a mechanism whereby long-term fertility can be impaired after chemotherapy exposure, despite the continuing presence of follicles within the ovary, and support the need for fertility preservation in prepubertal girls before alkylating agent exposure.


Assuntos
Blastocisto/efeitos dos fármacos , Ciclofosfamida/farmacologia , Desenvolvimento Embrionário/efeitos dos fármacos , Reserva Ovariana/efeitos dos fármacos , Maturidade Sexual/fisiologia , Animais , Hormônio Antimülleriano/sangue , Antineoplásicos Alquilantes/farmacologia , Blastocisto/citologia , Blastocisto/fisiologia , Peso Corporal/efeitos dos fármacos , Peso Corporal/fisiologia , Proliferação de Células/efeitos dos fármacos , Ciclofosfamida/administração & dosagem , Embrião de Mamíferos/efeitos dos fármacos , Embrião de Mamíferos/embriologia , Desenvolvimento Embrionário/fisiologia , Feminino , Fertilidade/efeitos dos fármacos , Fertilidade/fisiologia , Camundongos , Oócitos/efeitos dos fármacos , Oócitos/fisiologia , Tamanho do Órgão/efeitos dos fármacos , Reserva Ovariana/fisiologia , Ovário/anatomia & histologia , Ovário/citologia , Ovário/efeitos dos fármacos , Fatores de Tempo
20.
Ecotoxicol Environ Saf ; 201: 110820, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32531574

RESUMO

Growth hormone (GH)/insulin-like growth factor (IGF) axis plays a critical role in fetal development. However, the effect of arsenite exposure on the GH/IGF axis and its toxic mechanism are still unclear. Zebrafish embryos were exposed to a range of NaAsO2 concentrations (0.0-10.0 mM) between 4 and 120 h post-fertilization (hpf). Development indexes of survival, malformation, hatching rate, heart rate, body length and locomotor behavior were measured. Hormone levels, GH/IGF axis-related genes, and nerve-related genes were also tested. The results showed that survival rate, hatching rate, heart rate, body length and locomotor behavior all decreased, while deformity increased. At 120 hpf, the survival rate of zebrafish in 1.5 mM NaAsO2 group was about 70%, the deformity rate exceeded 20%, and the body length shortened to 3.35 mm, the movement distance of zebrafish decreased approximately 63.6% under light condition and about 52.4% under dark condition. The level of GH increased and those of IGF did not change significantly, while the expression of GH/IGF axis related genes (ghra, ghrb, igf2r, igfbp3, igfbp2a, igfbp5b) and nerve related genes (dlx2, shha, ngn1, elavl3, gfap) decreased. In 1.5 mM NaAsO2 group, the decrease of igfbp3 and igfbp5b was almost obvious, about 78.2% and 72.2%. The expression of nerve genes in 1.5 mM NaAsO2 group all have declined by more than 50%. These findings suggested that arsenite exerted disruptive effects on the endocrine system by interfering with the GH/IGF axis, leading to zebrafish embryonic developmental toxicity.


Assuntos
Arsenitos/toxicidade , Embrião não Mamífero/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Hormônio do Crescimento/metabolismo , Somatomedinas/metabolismo , Peixe-Zebra , Animais , Embrião não Mamífero/metabolismo , Desenvolvimento Embrionário/genética , Sistema Endócrino/efeitos dos fármacos , Sistema Endócrino/embriologia , Sistema Endócrino/metabolismo , Hormônio do Crescimento/genética , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/genética , Transdução de Sinais , Somatomedinas/genética , Peixe-Zebra/genética , Peixe-Zebra/metabolismo
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