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1.
Ecotoxicol Environ Saf ; 224: 112696, 2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34455182

RESUMO

Benoxacor (BN) is a highly effective antidote of dichloroacetamide herbicides generally used to protect crops from herbicidal damage. As a commonly used agrochemical, this herbicide antidote is continuously discharged in watercourses thus causing toxicity to aquatic organisms, and ultimately leading to contamination of the food chain. To date, its potential toxicity to the cardiac development of aquatic organisms has not been evaluated. In the present study, we have selected the zebrafish as a model to study the impact of BN on embryonic developmental and cardiac toxicity. The zebrafish embryos were exposed in 0.5, 1.0 and 2.0 mg/L BN from 5.5 to 72 h post-fertilization (hpf). The results indicated that the exposure to BN led to increased mortality and diminished heart and hatching rates in the embryos. BN exposure also brought pericardial edema (PE) and linear stretching of heart. Besides, exposure to BN induced an excessive accumulation of reactive oxygen species (ROS) in the zebrafish embryos and abnormal activities of the antioxidant enzymes, including catalase (CAT) and malondialdehyde (MDA). Moreover, exposure to BN caused serious cardiac toxicity of the embryos, accompanied by abnormality of heart development- and apoptosis-related genes. Surprisingly, astaxanthin (ASTA), as a common antioxidant, was found to be able to partially rescue the cardiac toxicity caused by BN, which indicated that ROS are probably the major reason for the resulting cardiotoxicity in zebrafish embryos. Our results suggest the need for a comprehensive safety evaluation of the regular consumption of benoxacor, which provides scientific basis for the development of health standards and assessment of potential risk in aquatic organisms or even human.

2.
Environ Toxicol ; 36(10): 2062-2072, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34227734

RESUMO

Quercetin is a flavonoid compound with a variety of biological properties that is widely distributed throughout the plant kingdom. Studies have found that quercetin has anti-inflammatory, antioxidant, and liver-protective effects, while thioacetamide (TAA) can cause inflammation and liver damage in zebrafish larvae. The purpose of this study was to evaluate whether quercetin can prevent TAA-induced inflammation and liver damage in zebrafish larvae and to investigate the molecular mechanisms involved. Zebrafish Tg transgenic lines were used as the experimental animals. Behavioral, oxidative stress level, proliferative antigen chromogenic antibody, and western blot analyses were carried out on zebrafish larvae in the control group and groups treated with TAA and 12 µM quercetin. The results indicated that quercetin promoted the development of zebrafish larvae damaged by TAA, exhibited antioxidant and anti-inflammatory properties, and promoted cell proliferation. Quercetin reduced the expression of p53 protein in zebrafish larvae injured by TAA, resulting in decreased levels of Bax and increased levels of Bcl-2. The findings suggested quercetin has antiapoptotic action. Quercetin reduced the expression of DKK1 and DKK2 genes related to the Wnt signaling pathway in zebrafish larvae damaged by TAA and increased the expression of Lef1 and wnt2bb. Quercetin may regulate the development of zebrafish larvae damaged by TAA through the Wnt signaling pathway. This study provides the scientific basis for the development and utilization of quercetin and the development of new related drugs.


Assuntos
Quercetina , Tioacetamida , Animais , Antioxidantes/metabolismo , Larva , Fígado/metabolismo , Estresse Oxidativo , Quercetina/farmacologia , Tioacetamida/toxicidade , Peixe-Zebra
3.
Ecotoxicol Environ Saf ; 222: 112514, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34280841

RESUMO

Pendimethalin (PND) is one of the best sellers of selective herbicide in the world and has been frequently detected in the water. However, little is known about its effects on cardiac development. In this study, we used zebrafish to investigate the developmental and cardiac toxicity of PND. We exposed the zebrafish embryos with a serial of concentrations at 3, 4, and 5 mg/L at 5.5-72 h post-fertilization (hpf). We found that PND exposure can reduce the heart rate, survival rate, and body length of zebrafish embryos. Furthermore, we identified many malformations including pericardial and yolk sac edema, spinal deformity, and cardiac looping abnormality. In addition, PND increased the expression of reactive oxygen species and malondialdehyde and reduced the activity of superoxide dismutase (Antioxidant enzymes); We examined the expression of cardiac development-related genes and the apoptosis markers, and found changes of the following marker: vmhc, nppa, tbx5a, nkx2.5, gata4, tbx2b and FoxO1, bax, bcl-2, p53, casp-9, casp-3. Our data showed that activation of Wnt pathway can rescue the cardiac abnormalities caused by PND. Our results provided new evidence for the toxicity of PND and suggested that the PND residual should be treated as a hazard in the environment.


Assuntos
Embrião não Mamífero , Peixe-Zebra , Compostos de Anilina , Animais , Apoptose , Cardiotoxicidade/metabolismo , Embrião não Mamífero/metabolismo , Estresse Oxidativo , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
4.
Opt Lett ; 46(13): 3143-3146, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34197401

RESUMO

In this Letter, we present a holography-based structured light illumination (SLI) method to enhance the resolution of widefield temporal focusing microscopy (TFM). In the system, a digital micromirror device is employed to simultaneously disperse the incoming femtosecond laser to induce temporal focusing at the focal plane and generate designed structured patterns via a Lee hologram. As the generated structured patterns do not contain the zeroth order beam, it improves the contrast and modulation frequency. Mathematical models have been derived to calculate the electric fields at the focal plane and to explain the effects of improved optical cross-sectioning capability. Imaging experiments have been devised and performed on fluorescent beads and mouse kidney sections; the results demonstrate enhanced axial confinement and improved suppression of out-of-focus fluorescence. The new SLI method realizes high-resolution TFM and can be readily applied to other microscopy platforms for biophotonics applications.

5.
Environ Pollut ; 285: 117323, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34091267

RESUMO

Evaluation of the toxicity of pesticide residues on non-target organisms in the ecosystem is an important part of pesticide environmental risk assessment. Flupyradifurone is a new type of butenolide insecticide produced by Bayer, who claims it to be "low toxic" to non-target organisms in the environment. However, there is little evidence in the literature to show how flupyradifurone affects aquatic organism development. In the current study, zebrafish embryos were treated with 0.1, 0.15, and 0.2 mg/mL of flupyradifurone within 6.0-72 h past fertilization (hpf). We found that the half-lethal concentration (LC50) of flupyradifurone for zebrafish embryos at 96 hpf was 0.21 mg/mL. Flupyradifurone decreases the heart rate, survival rate, and body length of zebrafish embryos. The flupyradifurone treatment also led to the failure of heart looping, and pericardial edema. Moreover, flupyradifurone increased the level of reactive oxygen species (ROS) and decreased the enzymatic catalysis of catalase (CAT) and superoxide dismutase (SOD). Alterations were induced in the transcription of apoptosis-related genes (bcl-2, bax, bax/bcl-2, p53 and caspase-9) and the heart development-related genes (gata4, myh6, nkx2.5, nppa, tbx2b, tbx5 and vmhc). In the current study, new evidences have been provided regarding the toxic effects of flupyradifurone and the risk of its residues in agricultural products and the environment.


Assuntos
Embrião não Mamífero , Peixe-Zebra , 4-Butirolactona/análogos & derivados , Animais , Apoptose , Ecossistema , Embrião não Mamífero/metabolismo , Desenvolvimento Embrionário , Estresse Oxidativo , Piridinas
6.
Aquat Toxicol ; 237: 105870, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34107429

RESUMO

Pyridaben is a widely used acaricide in agriculture and reaches a high concentration (97 µg/L) in paddy water for a short time when pyridaben was applied to rice. However, its toxicity to aquatic organisms is still poorly understood. Therefore, we assessed the pyridaben cardiotoxicity to aquatic organisms using the zebrafish (Danio rerio) model. We found that pyridaben is highly toxic to aquatic organisms, and LC50 of pyridaben for zebrafish at 72 hpf was 100.6 µg/L. Pyridaben caused severe cardiac malformations and functional abnormalities. Morphologic abnormity included severe pericardial edema, cardiomegaly, decreased cardiomyocytes, thinning of the myocardial layer, linear heart, and increased the distance between sinus venous and bulbus arteriosus (SV-BA). Functional failure included arrhythmia, heart failure, and reduced pumping efficiency. The genes involved in heart development, WNT signaling, BMP signaling, ATPase, and cardiac troponin C were abnormally expressed in the pyridaben treatment group. Exposure to pyridaben increased oxidative stress and induced cell apoptosis. The above causes may lead to cardiac toxicity. The results suggest that pyridaben exposure induced elevated oxidative stress through the WNT signaling pathway, which in turn led to apoptosis in the heart and cardiotoxicity. Besides, pyridaben exposure at the critical stage of cardiac looping (24-36 hpf) resulted in the greatest cardiotoxicity. The chorion reduced the entry of pyridaben and protected zebrafish embryos, resulting in cardiotoxicity second only to the stage of cardiac looping. The study should provide valuable information that pyridaben exposure causes cardiotoxicity in zebrafish embryos and have potential health risks for other aquatic organisms and humans.


Assuntos
Poluentes Químicos da Água , Peixe-Zebra , Animais , Cardiotoxicidade , Embrião não Mamífero , Humanos , Piridazinas , Poluentes Químicos da Água/toxicidade
7.
Ecotoxicol Environ Saf ; 220: 112385, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34082241

RESUMO

Sulfometuron methyl (SM) is a widely used herbicide and thus leading to accumulation in the environment. The toxicity assessments of SM in model organisms are currently rare. In the present study, zebrafish were utilized for evaluating the detrimental effects of SM in aquatic vertebrates. Zebrafish embryos were exposed to 0, 10, 20, and 40 mg/L SM from 5.5 to 72 h post-fertilization (hpf), respectively. Consequently, SM exposure resulted in increasing the mortality rate and reducing hatching rate in larval zebrafish at 10, 20, and 40 mg/L SM-treated groups. The reduced numbers of immune cells (neutrophils and macrophages) were observed after SM exposure by a dose-dependent manner. The inflammatory responses (TLR4, MYD88, IL-1ß, IL-6, IL-8, IFN-γ, IL-10, and TGF-ß) were measured to estimate immune responses. Anti-inflammatory factors (IL-10 and TGF-ß) were down-regulated in all the treated groups and significantly altered at 40 mg/L exposure group. Additionally, behavioral tests suggested that SM treatment significantly increased the total distance, average speed, and maximum acceleration of larval zebrafish during light-dark transition and subsequently enzymology test displayed the same trend to locomotor behaviors. The content significantly increased in oxidative stress, as reflected in ROS level in all the treated groups. The numbers of cell apoptosis were significantly increased at 20, and 40 mg/L and the highest concentration group induced the substantial increment (P < 0.001) of apoptosis-related genes including p53, Bax/Bcl-2, caspase-9, and caspase-3. In summary, our results demonstrated that exposure to SM caused toxicity of development, immune system, locomotor behavior, oxidative stress, and cell apoptosis at the early developmental stages of zebrafish.


Assuntos
Embrião não Mamífero/efeitos dos fármacos , Herbicidas/toxicidade , Compostos de Sulfonilureia/toxicidade , Peixe-Zebra/crescimento & desenvolvimento , Animais , Apoptose/efeitos dos fármacos , Catalase/metabolismo , Citocinas/genética , Citocinas/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Larva/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio , Superóxido Dismutase/metabolismo , Poluentes Químicos da Água/toxicidade
8.
Proc Natl Acad Sci U S A ; 118(2)2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-33376206

RESUMO

Planarian flatworms regenerate their heads and tails from anterior or posterior wounds and this regenerative blastema polarity is controlled by Wnt/ß-catenin signaling. It is well known that a regeneration blastema of appendages of vertebrates such as fish and amphibians grows distally. However, it remains unclear whether a regeneration blastema in vertebrate appendages can grow proximally. Here, we show that a regeneration blastema in zebrafish fins can grow proximally along the proximodistal axis by calcineurin inhibition. We used fin excavation in adult zebrafish to observe unidirectional regeneration from the anterior cut edge (ACE) to the posterior cut edge (PCE) of the cavity and this unidirectional regeneration polarity occurs as the PCE fails to build blastemas. Furthermore, we found that calcineurin activities in the ACE were greater than in the PCE. Calcineurin inhibition induced PCE blastemas, and calcineurin hyperactivation suppressed fin regeneration. Collectively, these findings identify calcineurin as a molecular switch to specify the PCE blastema of the proximodistal axis and regeneration polarity in zebrafish fin.


Assuntos
Nadadeiras de Animais/fisiologia , Calcineurina/metabolismo , Regeneração/fisiologia , Animais , Polaridade Celular/fisiologia , Extremidades/fisiologia , Transdução de Sinais , Cicatrização/fisiologia , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra
9.
Chemosphere ; 263: 127860, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32829219

RESUMO

Iprodione is a highly effective broad-spectrum fungicide commonly used for early disease control in fruit trees and vegetables. Pesticides often flow into watercourses due to rainfall, causing toxicity in non-target organisms, eventually entering the food chain. However, little information is available in the current literature about the toxicity of iprodione to cardiac development. The present study aimed to investigate the effect of iprodione on early embryonic development and its cardiotoxicity in aquatic animals, using zebrafish as a model. At 6-72 h post-fertilization (hpf), zebrafish were exposed to concentrations of 15 mg/L, 20 mg/L, and 25 mg/L (72 h-LC50 = 21.15 mg/L). We found that exposure to iprodione resulted in yolk edema, increased mortality, and shortened body length in zebrafish embryos. In addition, iprodione was also found to induce edema in the pericardium of zebrafish, decrease heart rate, and cause the failure of cardiac cyclization. Exposure to iprodione significantly increased the accumulation of ROS and altered the activity of antioxidant enzymes (MDA, CAT) in zebrafish embryos. Moreover, iprodione induced changes in the transcription levels of heart developmental-related genes and apoptosis-related genes. In addition, Astaxanthin (antioxidant) can partially rescue the toxic phenotype caused by iprodione. Apoptosis-related genes and heart developmental-related genes were rescued after astaxanazin treatment. The results suggest that iprodione induces developmental and cardiac toxicity in zebrafish embryos, which provides new evidence of the toxicity of iprodione to organisms in aquatic ecosystems and assessing human health risks.


Assuntos
Cardiotoxicidade , Peixe-Zebra , Aminoimidazol Carboxamida/análogos & derivados , Animais , Ecossistema , Embrião não Mamífero/metabolismo , Desenvolvimento Embrionário , Hidantoínas , Estresse Oxidativo
10.
Ecotoxicol Environ Saf ; 205: 111339, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32961491

RESUMO

Famoxadone-cymoxanil is a new protective and therapeutic fungicide, but little research has been done on it or its toxicity in aquatic organisms. In this study, we used zebrafish to investigate the cardiotoxicity of famoxadone-cymoxanil and the potential mechanisms involved. Zebrafish embryos were exposed to different concentrations of famoxadone-cymoxanil until 72 h post-fertilization (hpf), then changes of heart morphology in zebrafish embryos were observed. We also detected the levels of oxidative stress, myocardial-cell proliferation and apoptosis, ATPase activity, and the expression of genes related to the cardiac development and calcium-signaling pathway. After famoxadone-cymoxanil exposure, pericardial edema, cardiac linearization, and reductions in the heart rate and cardiac output positively correlated with concentration. Although myocardial-cell apoptosis was not detected, proliferation of the cells was severely reduced and ATPase activity significantly decreased, resulting in a severe deficiency in heart function. In addition, indicators of oxidative stress changed significantly after exposure of the embryos to the fungicide. To better understand the possible molecular mechanisms of cardiovascular toxicity in zebrafish, we studied the transcriptional levels of cardiac development, calcium-signaling pathways, and genes associated with myocardial contractility. The mRNA expression levels of key genes in heart development were significantly down-regulated, while the expression of genes related to the calcium-signaling pathway (ATPase [atp2a1], cardiac troponin C [tnnc1a], and calcium channel [cacna1a]) was significantly inhibited. Expression of klf2a, a major endocardial flow-responsive gene, was also significantly inhibited. Mechanistically, famoxadone-cymoxanil toxicity might be due to the downregulation of genes associated with the calcium-signaling pathway and cardiac muscle contraction. Our results found that famoxadone-cymoxanil exposure causes cardiac developmental toxicity and severe energy deficiency in zebrafish.


Assuntos
Acetamidas/toxicidade , Embrião não Mamífero/efeitos dos fármacos , Fungicidas Industriais/toxicidade , Coração/efeitos dos fármacos , Estrobilurinas/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/metabolismo , Animais , Apoptose/efeitos dos fármacos , Sinalização do Cálcio/efeitos dos fármacos , Sinalização do Cálcio/genética , Cardiotoxicidade , Regulação para Baixo , Embrião não Mamífero/metabolismo , Embrião não Mamífero/patologia , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Coração/embriologia , Frequência Cardíaca/efeitos dos fármacos , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Peixe-Zebra/crescimento & desenvolvimento , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
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.
Environ Pollut ; 265(Pt A): 114775, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32504889

RESUMO

Oxadiazon-Butachlor (OB) is a widely used herbicide for controlling most annual weeds in rice fields. However, its potential toxicity in aquatic organisms has not been evaluated so far. We used the zebrafish embryo model to assess the toxicity of OB, and found that it affected early cardiac development and caused extensive cardiac damage. Mechanistically, OB significantly increased oxidative stress in the embryos by inhibiting antioxidant enzymes that resulted in excessive production of reactive oxygen species (ROS), eventually leading to cardiomyocyte apoptosis. In addition, OB also inhibited the WNT signaling pathway and downregulated its target genes includinglef1, axin2 and ß-catenin. Reactivation of this pathway by the Wnt activator BML-284 and the antioxidant astaxanthin rescued the embryos form the cardiotoxic effects of OB, indicating that oxidative stress, and inhibition of WNT target genes are the mechanistic basis of OB-induced damage in zebrafish. Our study shows that OB exposure causes cardiotoxicity in zebrafish embryos and may be potentially toxic to other aquatic life and even humans.


Assuntos
Cardiotoxicidade , Peixe-Zebra , Acetanilidas , Animais , Embrião não Mamífero , Oxidiazóis , Estresse Oxidativo
13.
Chemosphere ; 256: 127038, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32470728

RESUMO

Baicalein is a flavonoid that is widely found in plants. Studies have shown that baicalein has anti-inflammatory, anti-cancer, and liver-protective effects. However, the effects of baicalein on TAA-induced toxicity and the underlying molecular mechanisms in zebrafish larvae are still unknown. Here, we investigated the effects of baicalein on liver development and its anti-inflammatory effects in zebrafish larvae. The results showed that baicalein has significant anti-embryonic developmental toxicity and significant antioxidant and anti-inflammatory capabilities in TAA-induced zebrafish larvae and promotes liver development and cell proliferation, reduces the expression of apoptotic proteins, and induces the expression of anti-apoptotic proteins. At the molecular level of TAA-treated zebrafish larvae, there was a decrease in the relative expression levels of mRNAs of three subfamilies, P38, ERK1, and ERK2, of the MAPK-signaling pathway and of the products of peroxisome proliferator-activated receptor (PPAR)α. Compared with TAA-treated zebrafish larvae, zebrafish larvae treated with baicalein showed an increase in the relative expression levels of P38, ERK1, and ERK2 mRNAs and the downstream products of PPARα. When MAPK signal inhibitor (SB203580) was added, it was found that liver development was inhibited and baicalin had no protective effect on TAA induced hepatotoxicity in zebrafish larvae. The results showed baicalein can protect the zebrafish larvae against toxicity induced by TAA through MAPK signal pathway. Several molecular mechanisms discovered in this study may help in the development of new drugs.


Assuntos
Flavanonas/toxicidade , Tioacetamida/toxicidade , Peixe-Zebra/fisiologia , Animais , Anti-Inflamatórios/metabolismo , Antioxidantes/metabolismo , Flavonoides , Larva/efeitos dos fármacos , Fígado/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , PPAR alfa , Substâncias Protetoras/metabolismo , Transdução de Sinais/efeitos dos fármacos
14.
BMC Plant Biol ; 20(1): 200, 2020 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-32384927

RESUMO

BACKGROUND: The interactions between Growth-regulating factors (GRFs) and GRF-Interacting Factors (GIFs) have been well demonstrated but it remains unclear whether different combinations of GRF and GIF play distinctive roles in the pathway downstream of the complex. RESULTS: Here we showed that OsGRF1 and OsGIF1 synergistically regulate leaf growth in rice. The expression of OsGIF1 emerged in all tissues with much higher level while that of OsGRF1 appeared preferentially only in the stem tips containing shoot apical meristem (SAM) and younger leaves containing leaf primordium. Overexpression of an OsmiR396-resistant version of mOsGRF1 resulted in expanded leaves due to increased cell proliferation while knockdown of OsGRF1 displayed an opposite phenotype. Overexpression of OsGIF1 did not exhibit new phenotype while knockdown lines displayed pleiotropic growth defects including shrunken leaves. The crossed lines of mOsGRF1 overexpression and OsGIF1 knockdown still exhibited shrunk leaves, indicating that OsGIF1 is indispensable in leaf growth regulated by OsGRF1. The expression of OsGRF1 could be upregulated by gibberellins (GAs) and downregulated by various stresses while that of OsGIF1 could not. CONCLUSION: Our results suggest that OsGIF1 is in an excessive expression in various tissues and play roles in various aspects of growth while OsGRF1 may specifically involve in leaf growth through titrating OsGIF1. Both internal and external conditions impacting leaf growth are likely via way of regulating the expression of OsGRF1.


Assuntos
Oryza/genética , Reguladores de Crescimento de Plantas/fisiologia , Folhas de Planta/crescimento & desenvolvimento , Técnicas de Silenciamento de Genes , Pleiotropia Genética , MicroRNAs/metabolismo , Reguladores de Crescimento de Plantas/genética
15.
Chemosphere ; 255: 126889, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32388256

RESUMO

Pyrimethanil is a broad-spectrum fungicide commonly used in the prevention and treatment of Botrytis cinerea. However, little information is available in the literature to show the toxicity of Pyrimethanil to cardiac development. In this study, we used an experimental animal model to explore the developmental and cardiac toxicity of Pyrimethanil in aquatic vertebrates; we exposed zebrafish embryos to Pyrimethanil at concentrations of 2, 4, and 6 mg/L from 5.5 to 72 h post fertilisation. We found that Pyrimethanil caused a decrease in the hatching rate, heart rate, and survival rate of zebrafish embryos. Pyrimethanil exposure also resulted in pericardial and yolk sac edema, spinal deformity, and heart loop failure. Moreover, Pyrimethanil increased reactive oxygen stress levels and heightened the activity of superoxide dismutase and catalase. Alterations were induced in the transcription of apoptosis-related genes (p53, Bax, Bcl2, Casp 9, and Casp6l1) and heart development-related genes (Tbx2b, Gata4, Myh6, Vmhc, Nppa, Bmp2b, Bpm 4, and Bpm 10). Our data showed that the activation of Wnt signalling by BML-284 could partially rescue the malformed phenotype caused by Pyrimethanil. Our results provide new evidence for Pyrimethanil's toxicity and the danger of its residues in the environment and agricultural products.


Assuntos
Fungicidas Industriais/toxicidade , Pirimidinas/toxicidade , Animais , Apoptose , Cardiotoxicidade , Caspase 9 , Embrião não Mamífero/metabolismo , Estresse Oxidativo , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
16.
Plant Physiol ; 182(4): 2213-2227, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31953375

RESUMO

GAs play key roles in controlling cell proliferation through the GIBBERELLIN INSENSITIVE DWARF1/DELLA-mediated pathway. However, how DELLA proteins affect downstream pathways is not well understood. Therefore, discovering the signaling events downstream of DELLAs is key to better understanding the roles of GAs in plant development. Here, we discovered that miR396 is regulated by SLENDER RICE1 (SLR1) in controlling cell proliferation. The positive response of rice (Oryza sativa) GROWTH-REGULATING FACTORs (OsGRFs) to GAs was found to be caused by a negative response of miR396 to GAs. miR396 acts downstream of SLR1 and upstream of GA-induced cell-cycle genes. Rice INDETERMINATE DOMAIN2 (OsIDD2) directly binds the promoter of OsmiR396a and can interact with SLR1 in vivo and in vitro. Rice lines overexpressing miR396a (miR396OE) or OsIDD2 (OsIDD2OE) displayed dwarfism resulting from higher abundance of miR396 RNA. However, the stem elongation of OsIDD2OE plants could be significantly stimulated by applying exogenous GA3, while that of miR396OE plants could not. Rice with OsIDD2 knocked down by RNA interference showed a slr1-like phenotype, in which the expression of miR396 was inhibited while its targets were enhanced. The protein levels of OsIDD2 were unaffected by GA in wild-type and OsIDD2OE plants, implying that OsIDD2 promotes the expression of miR396 and likely requires the coactivator of SLR1. Taken together, these results provided a close link between SLR1/OsIDD2 and GRFs via a negative regulator, miR396, and thus highlighted a molecular mechanism of GA-mediated cell proliferation in rice.


Assuntos
MicroRNAs/metabolismo , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , MicroRNAs/genética , Oryza/genética , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Regiões Promotoras Genéticas/genética , Regiões Promotoras Genéticas/fisiologia , Transdução de Sinais/genética , Transdução de Sinais/fisiologia
17.
Chemosphere ; 238: 124753, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31545217

RESUMO

Boscalid is a widely used fungicide in agriculture and has been frequently detected in both environments and agricultural products. However, evidence on the neurotoxic effect of boscalid is scarce. In this study, zebrafish served as an animal model to investigate the toxic effects and mechanisms of boscalid on aquatic vertebrates or higher animals. And we unravelled that boscalid induced developmental defects associated with oxidative stress. Developmental defects, including head deformity, hypopigmentation, decreased number of newborn neurons, structural defects around the ventricle, enlarged intercellular space in the brain, and nuclear concentration, were observed in zebrafish embryos after boscalid exposure at 48 hpf. Interestingly, we found that boscalid might directly induce oxidative stress and alter the activity of ATPase, which in turn disrupted the expression of genes involved in neurodevelopment and transmitter-transmitting signalings and melanocyte differentiation and melanin synthesis signalings. Ultimately, the differentiation of nerve cells and melanocytes were both impacted and the synthesis of melanin was inhibited, leading to morphological abnormalities. Additionally, exposure to boscalid led to less and imbalance motion and altered tendency of locomotor in larval fish. Collectively, our results provide new evidences for a comprehensive assessment of its toxicity and a warning for its residues in environment and agricultural products.


Assuntos
Compostos de Bifenilo/toxicidade , Fungicidas Industriais/toxicidade , Larva/efeitos dos fármacos , Niacinamida/análogos & derivados , Estresse Oxidativo/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/embriologia , Animais , Diferenciação Celular/efeitos dos fármacos , Modelos Animais de Doenças , Embrião não Mamífero/efeitos dos fármacos , Humanos , Melaninas/biossíntese , Melanócitos/citologia , Neurônios/citologia , Síndromes Neurotóxicas/patologia , Niacinamida/toxicidade , Peixe-Zebra/metabolismo
18.
PLoS One ; 14(9): e0222729, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31539402

RESUMO

In this paper, we present a new multi-focus microscope (MFM) system based on a phase mask and HiLo algorithm, achieving high-speed (20 volumes per second), high-resolution, low-noise 3-D fluorescent imaging. During imaging, the emissions from the specimen at nine different depths are simultaneously modulated and focused to different regions on a single CCD chip, i.e., the CCD chip is subdivided into nine regions to record images from the different selected depths. Next, HiLo algorithm is applied to remove the background noises and to form clean 3-D images. To visualize larger volumes, the nine layers are scanned axially, realizing fast 3-D imaging. In the imaging experiments, a mouse kidney sample of ~ 60 × 60 × 16 µm3 is visualized with only 10 raw images, demonstrating substantially enhanced resolution and contrast as well as suppressed background noises. The new method will find important applications in 3-D fluorescent imaging, e.g., recording fast dynamic events at multiple depths in vivo.


Assuntos
Algoritmos , Imageamento Tridimensional/métodos , Rim/diagnóstico por imagem , Microscopia Confocal/métodos , Microscopia de Fluorescência/métodos , Animais , Camundongos , Imagem Óptica/métodos , Reprodutibilidade dos Testes
19.
Fish Shellfish Immunol ; 86: 549-558, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30517881

RESUMO

Clethodim is one of the most widely used herbicides in agriculture, but its potential negative effects on aquatic organisms are still poorly understood. This study examined the effects of clethodim on zebrafish at aspects of early stage embryonic development, immune toxicity, cell apoptosis and locomotor behavior. Firstly, clethodim exposure markedly decreased the survival rate, body length, and heart rate and resulted in a series of morphological abnormalities, primarily spinal deformities (SD) and yolk sac edema, in zebrafish larvae. Secondly, the number of immune cells was substantially reduced but the levels of apoptosis and oxidative stress were significantly increased in a dose-dependent manner upon clethodim exposure. Thirdly, we evaluated the expression of some key genes in TLR signaling including TLR4, MyD88, and NF-κB p65 and they were all up-regulated by exposure to 300 µg/L clethodim. Meanwhile, some proinflammatory cytokines such as TNF-α, IL-1ß, IL8, and IFN-γ were also activated in both the mock and the TLR4-KD conditions. Moreover, the locomotor behaviors and the enzymatic activities of AChE were obviously inhibited but the levels of acetylated histone H3 were greatly increased by clethodim exposure. In addition, incubation of zebrafish larvae with acetylcholine receptor (AChR) agonist carbachol can partially rescue the clethodim-modulated locomotor behavior. Taken together, our results suggest that clethodim has the potential to induce developmental immunotoxicity and cause behavioral alterations in zebrafish larvae. The information presented in this study will help to elucidate the molecular mechanisms underlying clethodim exposure in aquatic ecosystems.


Assuntos
Cicloexanonas/toxicidade , Embrião não Mamífero/efeitos dos fármacos , Herbicidas/toxicidade , Imunidade Inata/efeitos dos fármacos , Peixe-Zebra/imunologia , Animais , Apoptose/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Feminino , Frequência Cardíaca/efeitos dos fármacos , Masculino , Movimento/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais , Receptores Toll-Like/metabolismo , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/embriologia
20.
Opt Express ; 25(19): 23109-23121, 2017 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-29041614

RESUMO

We present a new two-snapshot structured light illumination (SLI) reconstruction algorithm for fast image acquisition. The new algorithm, which only requires two mutually π phase-shifted raw structured images, is implemented on a custom-built temporal focusing fluorescence microscope (TFFM) to enhance its axial resolution via a digital micromirror device (DMD). First, the orientation of the modulated sinusoidal fringe patterns is automatically identified via spatial frequency vector detection. Subsequently, the modulated in-focal-plane images are obtained via rotation and subtraction. Lastly, a parallel amplitude demodulation method, derived based on Hilbert transform, is applied to complete the decoding processes. To demonstrate the new SLI algorithm, a TFFM is custom-constructed, where a DMD replaces the generic blazed grating in the system and simultaneously functions as a diffraction grating and a programmable binary mask, generating arbitrary fringe patterns. The experimental results show promising depth-discrimination capability with an axial resolution enhancement factor of 1.25, which matches well with the theoretical estimation, i.e, 1.27. Imaging experiments on pollen grain and mouse kidney samples have been performed. The results indicate that the two-snapshot algorithm presents comparable contrast reconstruction and optical cross-sectioning capability than those adopting the conventional root-mean-square (RMS) reconstruction method. The two-snapshot method can be readily applied to any sinusoidally modulated illumination systems to realize high-speed 3D imaging as less frames are required for each in-focal-plane image restoration, i.e., the image acquisition speed is improved by 2.5 times for any two-photon systems.

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