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1.
Ecotoxicol Environ Saf ; 203: 111043, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32888597

RESUMO

Intraspecific difference in toxicity brings uncertainty to ecological risk assessment (ERA) and water quality criteria (WQC) of chemicals. Here, we compared intraspecies sensitivity to toxicants for Mesocyclops leuckarti of which toxicity data was obtained from published literatures, and zebrafish Danio rerio of which toxicity data was done in this study). Due to the internal concentration of chemicals not measured, simplified toxicokinetic-toxicodynamic (TK-TD) models were used, and we investigated whether TK-TD parameters estimated by Bayesian method might represent the differences in sensitivity between life-stages of 2 species. The results demonstrated that the difference in TK-TD parameters (background mortality m0, no effect concentration NEC, the killing rate ks, and the dominant rate kd) could represent the toxicity difference between life-stages of individual species. The TK-TD model could predict toxicity in individual species (Cyprinus carpio L., Enchytraeus crypticus, Folsomia candida, Hyalella Azteca) exposed to different chemical concentrations and successfully extrapolate toxicity between different life stages of Mesocyclops leuckarti and Danio rerio by scaling several TK-TD parameters. The modified TK-TD model on the extrapolation toxicity of chemicals between life stages for species could be useful for the ERA and for deriving and revising WQC for chemicals.


Assuntos
Carpas/metabolismo , Copépodes/metabolismo , Embrião não Mamífero/efeitos dos fármacos , Larva/efeitos dos fármacos , Modelos Biológicos , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/metabolismo , Animais , Teorema de Bayes , Bioacumulação , Carpas/crescimento & desenvolvimento , Copépodes/crescimento & desenvolvimento , Embrião não Mamífero/metabolismo , Larva/metabolismo , Medição de Risco , Especificidade da Espécie , Toxicocinética , Peixe-Zebra/crescimento & desenvolvimento
2.
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
3.
Ecotoxicol Environ Saf ; 203: 111014, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32888589

RESUMO

Tributyltin (TBT), a widely and persistently distributed organontin, has been well documented to disrupt reproduction and behaviors in animals due to its anti-aromatase activity. TBT has been also reported to enhance anxiety in several fish species, whereas the mechanism underlying remains largely unknown. To investigate the disruption of TBT on fish anxiety and the mechanisms possibly involved, adult male zebrafish (Danio rerio) were treated with TBT (100 and 500 ng/L) for 28 days and anxiety behavior was further investigated using a novel tank dive test. Result showed that TBT treatment significantly enhanced the total time of the fish spent in the lower half, delayed the onset time to the higher half of the tank and increased the total duration of freezing of the fish, indicating an enhanced anxiety in TBT-treated fish. Accordingly, TBT sharply elevated the cortisol levels in plasma in a concentration-dependent manner, suggesting that the elevated cortisol level might be involved in the enhanced anxiety. Although the expression of crha was significantly increased and crhbp was significantly decreased in the brain of TBT-treated fish which is consistent to the elevated cortisol level, the expressions of actha and acthb were sharply down-regulated. In contrast, the expressions of genes responsible for the synthesis and action of serotonin (5-HT) (pet1, thp2 and htr1aa), dopamine (DA) (th1, slc6a3, drd2a and drd2b) and gamma-aminobutyric acid (GABA) (gad2 and gabrg2) were all significantly inhibited. The down-regulation of these pivotal genes acting in 5-HT, DA and GABA neurotransmitter systems in response to TBT corresponded well with the TBT-enhanced anxiety in fish. It was thus strongly suggested that these neurotransmitters might be also involved in TBT-enhanced anxiety in adult male zebrafish. The present study extended our understanding of the neurotoxicity of TBT on the anxiety control and behavioral modulation in fish.


Assuntos
Ansiedade/induzido quimicamente , Hidrocortisona/metabolismo , Neurotransmissores/metabolismo , Compostos de Trialquitina/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Dopamina/metabolismo , Masculino , Serotonina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Peixe-Zebra/metabolismo , Ácido gama-Aminobutírico/metabolismo
4.
PLoS One ; 15(8): e0231364, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32804943

RESUMO

Phosphoinositides (PIPs) and their regulatory enzymes are key players in many cellular processes and are required for aspects of vertebrate development. Dysregulated PIP metabolism has been implicated in several human diseases, including a subset of skeletal myopathies that feature structural defects in the triad. The role of PIPs in skeletal muscle formation, and particularly triad biogenesis, has yet to be determined. CDP-diacylglycerol-inositol 3-phosphatidyltransferase (CDIPT) catalyzes the formation of phosphatidylinositol, which is the base of all PIP species. Loss of CDIPT should, in theory, result in the failure to produce PIPs, and thus provide a strategy for establishing the requirement for PIPs during embryogenesis. In this study, we generated cdipt mutant zebrafish and determined the impact on skeletal myogenesis. Analysis of cdipt mutant muscle revealed no apparent global effect on early muscle development. However, small but significant defects were observed in triad size, with T-tubule area, inter terminal cisternae distance and gap width being smaller in cdipt mutants. This was associated with a decrease in motor performance. Overall, these data suggest that myogenesis in zebrafish does not require de novo PIP synthesis but does implicate a role for CDIPT in triad formation.


Assuntos
CDP-Diacilglicerol-Inositol 3-Fosfatidiltransferase/metabolismo , Fosfatidilinositóis/biossíntese , Fosfatidilinositóis/metabolismo , Animais , CDP-Diacilglicerol-Inositol 3-Fosfatidiltransferase/biossíntese , Fosfatos de Inositol/metabolismo , Lipogênese , Desenvolvimento Muscular/genética , Músculos/metabolismo , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/metabolismo
5.
PLoS One ; 15(7): e0225351, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32735563

RESUMO

Endothelial cilia are found in a variety of tissues including the cranial vasculature of zebrafish embryos. Recently, endothelial cells in the developing mouse retina were reported to also possess primary cilia that are potentially involved in vascular remodeling. Fish carrying mutations in intraflagellar transport (ift) genes have disrupted cilia and have been reported to have an increased rate of spontaneous intracranial hemorrhage (ICH), potentially due to disruption of the sonic hedgehog (shh) signaling pathway. However, it remains unknown whether the endothelial cells forming the retinal microvasculature in zebrafish also possess cilia, and whether endothelial cilia are necessary for development and maintenance of the blood-retinal barrier (BRB). In the present study, we found that the endothelial cells lining the zebrafish hyaloid vasculature possess primary cilia during development. To determine whether endothelial cilia are necessary for BRB integrity, ift57, ift88, and ift172 mutants, which lack cilia, were crossed with the double-transgenic zebrafish strain Tg(l-fabp:DBP-EGFP;flk1:mCherry). This strain expresses a vitamin D-binding protein (DBP) fused to enhanced green fluorescent protein (EGFP) as a tracer in the blood plasma, while the endothelial cells forming the vasculature are tagged by mCherry. The Ift mutant fish develop a functional BRB, indicating that endothelial cilia are not necessary for early BRB integrity. Additionally, although treatment of zebrafish larvae with Shh inhibitor cyclopamine results in BRB breakdown, the Ift mutant fish were not sensitized to cyclopamine-induced BRB breakdown.


Assuntos
Barreira Hematorretiniana/metabolismo , Cílios/metabolismo , Células Endoteliais/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Animais Geneticamente Modificados , Barreira Hematorretiniana/efeitos dos fármacos , Barreira Hematorretiniana/fisiologia , Células Endoteliais/citologia , Proteínas Hedgehog/antagonistas & inibidores , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Larva/metabolismo , Mutagênese , Vasos Retinianos/citologia , Transdução de Sinais , Alcaloides de Veratrum/farmacologia , Peixe-Zebra/crescimento & desenvolvimento , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
6.
Chemosphere ; 258: 127408, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32782161

RESUMO

This study investigates the impacts of exposure to an environment Ca2+ challenge and the mechanism of action of dibutyl phthalate (DBP) on Ca2+ influx in the gills of Danio rerio. In vitro profile of 45Ca2+ influx in gills was verified through the basal time-course. Fish were exposed to low, normal and high Ca2+ concentrations (0.02, 0.7 and 2 mM) for 12 h. So, gills were morphologically analysed and ex vivo45Ca2+ influx at 30 and 60 min was determined. For the in vitro studies, gills were treated for 60 min with DBP (1 pM, 1 nM and 1 µM) with/without blockers/activators of ionic channels, Ca2+ chelator, inhibitors of ATPases, ionic exchangers and protein kinase C to study the mechanism of DBP-induced 45Ca2+ influx. Exposure to high environmental Ca2+ augmented 45Ca2+ influx when compared to fish exposed to normal and low Ca2+ concentrations. Additionally, histopathological changes were observed in the gills of fish maintained for 12 h in low and high Ca2+. In vitro exposure of gills to DBP (1 pM) disturbed Ca2+ homeostasis. DBP stimulated 45Ca2+ influx in gills through the transitory receptor potential vanilloid 1 (TRPV1), and reverse-mode Na+/Ca2+ exchanger (NCX) activation, protein kinase C and K+ channels and sarco/endoplasmic reticulum Ca2+-ATPase (SERCA). These data suggest that in vivo short-term exposure of gills to low and high Ca2+ leads to 45Ca2+ influx and histopathological changes. Additionally, the DBP-induced rapid 45Ca2+ influx is mediated by TRPV1, NCX activation with the involvement of PKC, K+-channels and SERCA, thereby altering Ca2+ homeostasis.


Assuntos
Radioisótopos de Cálcio/metabolismo , Cálcio/metabolismo , Dibutilftalato/toxicidade , Brânquias/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/metabolismo , Animais , Cálcio/toxicidade , Dibutilftalato/metabolismo , Retículo Endoplasmático/metabolismo , Brânquias/metabolismo , Trocador de Sódio e Cálcio/metabolismo , Canais de Cátion TRPV/metabolismo , Poluentes Químicos da Água/metabolismo
7.
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
8.
Aquat Toxicol ; 225: 105525, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32629302

RESUMO

Halogenated dipeptides, 3, 5-di-I-tyrosylalanine (DIYA), have been identified as novel disinfection byproducts (DBPs), following chloramination of authentic water. However, little is known about their toxicity. Zebrafish embryos were used to assess the toxicity of novel iodinated DBPs (I-DBPs). Although DIYA did not exhibit high acute toxicity to embryonic zebrafish (LC50 > 2 mM), it significantly inhibited pigmentation of melanophores and xanthophores on head, trunk and tail at 500 µM as determined by photographic analysis. Whereas N-phenylthiourea (PTU) as a pigment inhibitor did not inhibit development of yellow pigments. Colorimetric detection of melanin further confirmed these results. Quantitative real time polymerase chain reaction (qRT-PCR) measurements indicated that genes (dct, slc24a5, tyr, tyrp1a, tyrp1b, silva) associated with the melanogenesis pathway were dramatically down-regulated following exposure to 500 µM DIYA. In addition, enzymatic activity of tyrosinase (TYR) decreased, also demonstrating that the underlying mechanism of hypopigmentation was attributed to the disruption of melanogenesis pathway. Transcription levels of xanthophore genes (gch2, bnc2, csf1a, csf1b, pax7a and pax7b) were also monitored by qRT-PCR assay. DIYA exposure up-regulated expression of gch2 and bnc2, but not csf1 and pax7. Tested DIYA analogues, brominated tyrosine was unlikely to inhibit pigmentation, indicating that the iodine substitution and dipeptides structure are of important structural feature for the inhibition of pigmentation. In this study, we observed that DIYA inhibited melanogenesis related genes, which might contribute to pigmentation defects. Moreover, as an emerging I-DBPs, the developmental toxicity of aromatic dipeptides should be further studied.


Assuntos
Dipeptídeos/toxicidade , Desinfetantes/toxicidade , Embrião não Mamífero/efeitos dos fármacos , Hipopigmentação/induzido quimicamente , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/metabolismo , Animais , Embrião não Mamífero/metabolismo , Expressão Gênica/efeitos dos fármacos , Halogenação , Hipopigmentação/genética , Melanóforos/efeitos dos fármacos , Melanóforos/metabolismo , Purificação da Água , Proteínas de Peixe-Zebra/genética
9.
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
10.
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
11.
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
12.
Chemosphere ; 260: 127622, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32673875

RESUMO

In this study, fluorene (FL), FL-1-carboxylic acid (FC-1), and FL-9-carboxylic acid (FC-9) were investigated to understand their acute toxicity by measuring inhibitory effects on hatching rates and developmental processes of zebrafish embryos (Danio rerio). For exposure concentrations up to 3000 µg/L, FC-1 alone showed acute toxicity at 1458 µg/L for LC50 value. FC-1 caused yolk sac and spinal deformities, and pericardial edema. Molecular studies were undertaken to understand FC-1 toxicity examining 61 genes after exposure to 5 µM (equivalent to LC20 value of FC-1) in embryos. In the FC-1-treated embryos, the expression of the cyp7a1 gene, involved in bile acid biosynthesis, was dramatically decreased, while the expression of the Il-1ß gene involved in inflammation was remarkably increased. In addition to these findings, in FC-1-treated embryos, the expression of nppa gene related to the differentiation of the myocardium was 3-fold increased. On the other hand, cyp1a, cyp3a, ugt1a1, abcc4, mdr1, and sult1st1 responsible for detoxification of xenobiotics were upregulated in FC-9-treated embryos. Taken together, carboxylation on carbon 1 of FL increased acute toxicity in zebrafish embryos, and its toxicity might be related to morphological changes with modification of normal biological functions and lowered defense ability.


Assuntos
Fluorenos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Ácidos Carboxílicos/metabolismo , Embrião não Mamífero/efeitos dos fármacos , Fluorenos/metabolismo , Peixe-Zebra/metabolismo
13.
Chemosphere ; 260: 127609, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32693259

RESUMO

The environmental contaminant 3,3'-dichlorobiphenyl (PCB-11) is widely detected in environmental samples, and this parent compound along with its metabolites 4-OH-PCB-11 and 4-PCB-11-Sulfate are detected in human serum. Our previous research in zebrafish (Danio rerio) embryos shows exposure to 20 µM PCB-11 inhibits Cyp1a enzyme activity and perturbs lipid metabolism pathways. In this study, wildtype AB embryos underwent acute exposures from 1 to 4 days post fertilization (dpf) to 0.002-20 µM 4-OH-PCB-11 or 0.2-20 µM 4-PCB-11-Sulfate, with and without co-exposures to 100 µg/L benzo[a]pyrene (B[a]P) or 5 nM 3,3',4,4',5-pentachlorobiphenyl (PCB-126), and were assessed for in vivo EROD activity and morphometrics. Chronic exposures from 1 to 15 dpf to assess lipid accumulation using Oil-Red-O staining were also conducted with 0.2 µM parent or metabolite compounds, alongside a co-exposure experiment of 0.002-0.2 µM 4-PCB-11-Sulfate and 10 µg/L B[a]P. For acute experiments, 2 and 20 µM 4-OH-PCB-11 was lethal but no Cyp1a or morphological effects were observed at lower concentrations; 20 µM 4-PCB-11-Sulfate significantly lowered the Cyp1a activity of B[a]P and PCB-126 but did not alter morphological development. For chronic experiments, 0.2 µM 4-PCB-11-Sulfate significantly increased lipid accumulation 30% in single exposures and 44% in co-exposures with B[a]P. Further long-term studies would better elucidate the effects of this contaminant, particularly in the context of environmentally-relevant mixtures.


Assuntos
Bifenilos Policlorados/toxicidade , Peixe-Zebra/fisiologia , Animais , Benzo(a)pireno/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Embrião não Mamífero/metabolismo , Larva/metabolismo , Lipídeos , Fígado/metabolismo , Bifenilos Policlorados/metabolismo , Sulfatos/metabolismo , Peixe-Zebra/metabolismo
14.
Toxicol Lett ; 331: 143-151, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32525014

RESUMO

Although organotin compounds are known to disturb thyroid signaling and antioxidant defense system, the sex-differences underlying these effects of triphenyltin chloride (TPT) in fish remain unclear. To understand these differences, adult zebrafish (Danio rerio) were exposed to different concentrations of TPT (0, 10, 100, or 1000 ng/L) for 28 days. Female zebrafish exposed to TPT showed significantly increased thyroxine (T4) content and decrease triiodothyronine (T3) content, possibly due to downregulation of deiodinase (dio2) and uridine diphosphate glucuronosyl transferase (ugt1ab). However, decreased T4 and T3 contents in male zebrafish accompanied with upregulation of dio1, dio2 and ugt1ab. TPT exposure can lead to sex-specific thyroid disruption in adult zebrafish via alterations the Hypothalamus-pituitary-thyroid-liver axis. In addition, the gene expression levels of metabolizing enzymes, such as cyp1b, cyp1c, gpx1a, or sult1st1 were also to vary in a sex-dependent manner in adult zebrafish liver. Downregulation of cyp19a and cyp19b and decreased 17ß-estradiol (E2) contents were detected in both female and male zebrafish. Therefore, a sex-specific of thyroid disruption response after TPT exposure was observed in adult zebrafish, possibly due to inherent in female or males detoxifying enzyme capacities.


Assuntos
Disruptores Endócrinos/toxicidade , Compostos Orgânicos de Estanho/toxicidade , Caracteres Sexuais , Glândula Tireoide/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Proteínas de Peixe-Zebra , Peixe-Zebra/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/enzimologia , Relação Dose-Resposta a Droga , Feminino , Expressão Gênica/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/enzimologia , Masculino , Glândula Tireoide/metabolismo , Hormônios Tireóideos/genética , Hormônios Tireóideos/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
15.
Nat Commun ; 11(1): 2724, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32483144

RESUMO

Proteolytical processing of the growth factor VEGFC through the concerted activity of CCBE1 and ADAMTS3 is required for lymphatic development to occur. How these factors act together in time and space, and which cell types produce these factors is not understood. Here we assess the function of Adamts3 and the related protease Adamts14 during zebrafish lymphangiogenesis and show both proteins to be able to process Vegfc. Only the simultaneous loss of both protein functions results in lymphatic defects identical to vegfc loss-of-function situations. Cell transplantation experiments demonstrate neuronal structures and/or fibroblasts to constitute cellular sources not only for both proteases but also for Ccbe1 and Vegfc. We further show that this locally restricted Vegfc maturation is needed to trigger normal lymphatic sprouting and directional migration. Our data provide a single-cell resolution model for establishing secretion and processing hubs for Vegfc during developmental lymphangiogenesis.


Assuntos
Fibroblastos/metabolismo , Linfangiogênese/genética , Neurônios/metabolismo , Fator C de Crescimento do Endotélio Vascular/genética , Proteínas de Peixe-Zebra/genética , Peixe-Zebra/genética , Proteínas ADAMTS/genética , Proteínas ADAMTS/metabolismo , Animais , Animais Geneticamente Modificados , Regulação da Expressão Gênica no Desenvolvimento , Células HEK293 , Humanos , Vasos Linfáticos/embriologia , Vasos Linfáticos/metabolismo , Microscopia Confocal , Pró-Colágeno N-Endopeptidase/genética , Pró-Colágeno N-Endopeptidase/metabolismo , Fator C de Crescimento do Endotélio Vascular/metabolismo , Peixe-Zebra/embriologia , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/metabolismo
16.
Nat Commun ; 11(1): 2718, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32483191

RESUMO

Genome-wide association studies (GWAS) have identified ~20 melanoma susceptibility loci, most of which are not functionally characterized. Here we report an approach integrating massively-parallel reporter assays (MPRA) with cell-type-specific epigenome and expression quantitative trait loci (eQTL) to identify susceptibility genes/variants from multiple GWAS loci. From 832 high-LD variants, we identify 39 candidate functional variants from 14 loci displaying allelic transcriptional activity, a subset of which corroborates four colocalizing melanocyte cis-eQTL genes. Among these, we further characterize the locus encompassing the HIV-1 restriction gene, MX2 (Chr21q22.3), and validate a functional intronic variant, rs398206. rs398206 mediates the binding of the transcription factor, YY1, to increase MX2 levels, consistent with the cis-eQTL of MX2 in primary human melanocytes. Melanocyte-specific expression of human MX2 in a zebrafish model demonstrates accelerated melanoma formation in a BRAFV600E background. Our integrative approach streamlines GWAS follow-up studies and highlights a pleiotropic function of MX2 in melanoma susceptibility.


Assuntos
Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla/métodos , Melanoma/genética , Mutação , Proteínas de Resistência a Myxovirus/genética , Polimorfismo de Nucleotídeo Único , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Regulação da Expressão Gênica , Genes Reporter/genética , Células HEK293 , Humanos , Melanócitos/metabolismo , Melanoma/patologia , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Locos de Características Quantitativas/genética , Peixe-Zebra/genética , Peixe-Zebra/metabolismo
17.
PLoS One ; 15(6): e0228758, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32497052

RESUMO

Nutritional Programming (NP) has been studied as a means of mitigating the negative effects of dietary plant protein (PP), but the optimal timing and mechanism behind NP are still unknown. The objectives of this study were: 1) To determine whether zebrafish (Danio rerio) can be programmed to soybean meal (SBM) through early feeding and broodstock exposure to improve SBM utilization; 2) To determine if NP in zebrafish affects expression of genes associated with intestinal nutrient uptake; 3) To determine if early stage NP and/or broodstock affects gene expression associated with intestinal inflammation or any morphological changes in the intestinal tract that might improve dietary SBM utilization. Two broodstocks were used to form the six experimental groups. One broodstock group received fishmeal (FM) diet (FMBS), while the other was fed ("programmed with") SBM diet (PPBS). The first ((+) Control) and the second group ((-) Control) received FM and SBM diet for the entire study, respectively, and were progeny of FMBS. The last four groups consisted of a non-programmed (FMBS-X-PP and PPBS-X-PP) and a programmed group (FMBS-NP-PP and PPBS-NP-PP) from each of the broodstocks. The programming occurred through feeding with SBM diet during 13-23 dph. The non-control groups underwent a PP-Challenge, receiving SBM diet during 36-60 dph. During the PP-Challenge, both PPBS groups experienced significantly lower weight gains than the (+) Control group. NP in early life stages significantly increased the expression of PepT1 in PPBS-NP-PP, compared to PPBS-X-PP. NP also tended to increase the expression of fabp2 in the programmed vs. non-programmed groups of both broodstocks. The highest distal villus length-to-width ratio was observed in the dual-programmed group, suggesting an increase in surface area for nutrient absorption within the intestine. The results of this study suggest that NP during early life stages may increase intestinal absorption of nutrients from PP-based feeds.


Assuntos
Dieta , Proteínas na Dieta/metabolismo , Absorção Intestinal/efeitos dos fármacos , Plantas/química , Animais , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas de Vegetais Comestíveis , Fatores de Tempo , Peixe-Zebra/genética , Peixe-Zebra/crescimento & desenvolvimento , Peixe-Zebra/metabolismo
18.
Ecotoxicol Environ Saf ; 202: 110876, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32563953

RESUMO

This study investigated the acute in vitro effect of low-concentration bisphenol A (BPA) on calcium (45Ca2+) influx in zebrafish (Danio rerio) testis and examined whether intracellular Ca2+ was involved in the effects of BPA on testicular toxicity. In vitro studies on 45Ca2+ influx were performed in the testes after incubation with BPA for 30 min. Inhibitors were added 15 min before the addition of 45Ca2+ and BPA to testes to study the mechanism of action of BPA. The involvement of intracellular calcium from stores on lactate dehydrogenase (LDH) release and on triacylglycerol (TAG) content were carried out after in vitro incubation of testes with BPA for 1 h. Furthermore, gamma-glutamyl transpeptidase (GGT) and aspartate aminotransferase (AST) activities were analyzed in the liver at 1 h after in vitro BPA incubation of D. rerio. Our data show that the acute in vitro treatment of D. rerio testes with BPA at very low concentration activates plasma membrane ionic channels, such as voltage-dependent calcium channels and calcium-dependent chloride channels, and protein kinase C (PKC), which stimulates Ca2+ influx. In addition, BPA increased cytosolic Ca2+ by activating inositol triphosphate receptor (IP3R) and inhibiting sarco/endoplasmic reticulum calcium ATPase (SERCA) at the endoplasmic reticulum, contributing to intracellular Ca2+ overload. The protein kinases, PKC, MEK 1/2 and PI3K, are involved in the mechanism of action of BPA, which may indicate a crosstalk between the non-genomic initiation effects mediated by PLC/PKC/IP3R signaling and genomic responses of BPA mediated by the estrogen receptor (ESR). In vitro exposure to a higher concentration of BPA caused cell damage and plasma membrane injury with increased LDH release and TAG content; both effects were dependent on intracellular Ca2+ and mediated by IP3R. Furthermore, BPA potentially induced liver damage, as demonstrated by increased GGT activity. In conclusion, in vitro effect of BPA in a low concentration triggers cytosolic Ca2+ overload and activates downstream protein kinases pointing to a crosstalk between its non-genomic and genomic effects of BPA mediated by ESR. Moreover, in vitro exposure to a higher concentration of BPA caused intracellular Ca2+-dependent testicular cell damage and plasma membrane injury. This acute toxicity was reinforced by increased testicular LDH release and GGT activity in the liver.


Assuntos
Compostos Benzidrílicos/toxicidade , Cálcio/metabolismo , Fenóis/toxicidade , Testículo/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/fisiologia , Animais , Membrana Celular/metabolismo , Citosol/metabolismo , Retículo Endoplasmático/metabolismo , Receptores de Inositol 1,4,5-Trifosfato/antagonistas & inibidores , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Canais Iônicos , Masculino , Proteína Quinase C/metabolismo , Proteína Quinase C/farmacologia , Transdução de Sinais/efeitos dos fármacos , Testículo/metabolismo , Peixe-Zebra/metabolismo
19.
Ecotoxicol Environ Saf ; 202: 110892, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32593098

RESUMO

Carbon nanotubes presence in the environment increases every year because of exponential industrial production around the world. In aquatic environments, carbon nanotubes can interact with other pollutants based on their adsorbent surface chemistry properties. Heavy metal ions represent one of the biggest concerns in water resources nowadays due to anthropogenic activities, in which cadmium (Cd) is one of the most harmful metal for aquatic organisms. This study investigated the influence of two co-exposure protocols differing by the order of interaction of oxidized multiwalled carbon nanotubes (ox-MWCNT) with Cd in zebrafish liver cell line (ZFL). The ox-MWCNT was characterized, Cd content in culture medium and uptake by cells were quantified using ICP-MS and, the reactive oxygen species (ROS), the biotransformation enzymes activity of phase I and II as well as the antioxidants defenses and oxidative damage were analyzed. The effects on the cell cycle were investigated by flow cytometry and DNA damage by comet assay. The exposure to ox-MWCNT alone decreased the activity of catalase, glutathione peroxidase, and glutathione S-transferase and altered the cell cycle with a reduction of cells in the G2/M phase. Cd exposure alone decreased the activity of catalase and glutathione S-transferase, increased ROS, metallothionein, and lipid peroxidation content and causes genotoxicity in the cells. Despite different incubation protocol, the co-exposure ox-MWCNT-Cd increased the Cd content in ZFL cells after 24 h exposure, increased ROS production and DNA damage without differences between them. Our results showed the modulation of ox-MWCNT on Cd effects and contributed to future co-exposure toxicity investigations and nanosafety regulations involving carbon nanomaterials and aquatic pollutants.


Assuntos
Cádmio/toxicidade , Nanotubos de Carbono/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/metabolismo , Catalase/metabolismo , Ciclo Celular , Linhagem Celular , Ensaio Cometa , Dano ao DNA , Glutationa Peroxidase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Metais Pesados/farmacologia , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Testes de Toxicidade , Peixe-Zebra/metabolismo
20.
PLoS One ; 15(6): e0232308, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32530962

RESUMO

Zebrafish have the ability to regenerate damaged cells and tissues by activating quiescent stem and progenitor cells or reprogramming differentiated cells into regeneration-competent precursors. Proliferation among the cells that will functionally restore injured tissues is a fundamental biological process underlying regeneration. Midkine-a is a cytokine growth factor, whose expression is strongly induced by injury in a variety of tissues across a range of vertebrate classes. Using a zebrafish Midkine-a loss of function mutant, we evaluated regeneration of caudal fin, extraocular muscle and retinal neurons to investigate the function of Midkine-a during epimorphic regeneration. In wildtype zebrafish, injury among these tissues induces robust proliferation and rapid regeneration. In Midkine-a mutants, the initial proliferation in each of these tissues is significantly diminished or absent. Regeneration of the caudal fin and extraocular muscle is delayed; regeneration of the retina is nearly completely absent. These data demonstrate that Midkine-a is universally required in the signaling pathways that convert tissue injury into the initial burst of cell proliferation. Further, these data highlight differences in the molecular mechanisms that regulate epimorphic regeneration in zebrafish.


Assuntos
Midkina/metabolismo , Regeneração/fisiologia , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/metabolismo , Nadadeiras de Animais/fisiologia , Animais , Animais Geneticamente Modificados/metabolismo , Diferenciação Celular , Proliferação de Células , Midkina/genética , Mutagênese , Neuroglia/citologia , Neuroglia/metabolismo , Músculos Oculomotores/fisiologia , Neurônios Retinianos/fisiologia , Proteínas de Peixe-Zebra/genética
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