RESUMO
Coriander is a notable medicinal plant known for its diverse properties, including anti-inflammatory, antioxidant, anticancer, analgesic, and anti-diabetic effects. Despite its recognized health benefits, research on its nephroprotective properties is limited. This study aimed to investigate the potential nephroprotective properties of an aqueous extract derived from coriander leaves using an aristolochic acid-intoxicated zebrafish model. To assess kidney abnormalities induced by aristolochic acid (AA), we utilized the transgenic line Tg(wt1b:egfp), which expresses green fluorescent protein (GFP) in the kidney. Our previous report indicated that AA exposure leads to acute renal failure in zebrafish characterized by kidney malformation and impaired renal function. However, pretreatment of coriander extract (CE) can mitigate kidney malformations induced by AA. In addition, CE pretreatment reduces the accumulation of red blood cells in the glomerular region. To verify the nephroprotective effects of CE, we analyzed renal function by measuring the glomerular filtration rate in zebrafish embryos. Results indicate that CE partially mitigates renal function impairment caused by AA exposure, suggesting its potential to attenuate AA-induced renal failure. Mechanistically, pretreatment with CE reduces the expression of proinflammatory and proapoptotic genes induced by AA. This suggests that CE likely alleviates acute renal failure by reducing inflammation and apoptosis. As a result, we regard zebrafish as a valuable model for screening natural compounds that have the potential to alleviate AA-induced nephrotoxicity.
Assuntos
Ácidos Aristolóquicos , Coriandrum , Embrião não Mamífero , Rim , Extratos Vegetais , Folhas de Planta , Peixe-Zebra , Animais , Ácidos Aristolóquicos/toxicidade , Extratos Vegetais/farmacologia , Folhas de Planta/química , Embrião não Mamífero/efeitos dos fármacos , Rim/efeitos dos fármacos , Rim/patologia , Coriandrum/química , Animais Geneticamente Modificados , Substâncias Protetoras/farmacologiaRESUMO
Most cases of acquired aplastic anemia (AA) arise from autoimmune destruction of hematopoietic stem and progenitor cells. Human leukocyte antigen (HLA)-haploidentical nonmyeloablative hematopoietic stem cell transplantation (HSCT) plus post-transplantation cyclophosphamide (PTCy) is increasingly applied to salvage AA using bone marrow as graft and anti-thymocyte globulin (ATG) in conditioning. Herein, we characterize a cohort of twelve AA patients clinically and molecularly, six who possessed other immunological disorders (including two also carrying germline SAMD9L mutations). Each patient with SAMD9L mutation also carried an AA-related rare BCORL1 variant or CTLA4 p.T17A GG genotype, respectively, and both presented short telomere lengths. Six of the ten patients analyzed harbored AA-risky HLA polymorphisms. All patients recovered upon non-HSCT (n = 4) or HSCT (n = 8) treatments. Six of the eight HSCT-treated patients were subjected to a modified PTCy-based regimen involving freshly prepared peripheral blood stem cells (PBSC) as graft and exclusion of ATG. All patients were engrafted between post-transplantation days +13 and +18 and quickly reverted to normal life, displaying a sustained complete hematologic response and an absence of graft-versus-host disease. These outcomes indicate most AA cases, including of the SAMD9L-inherited subtype, are immune-mediated and the modified PTCy-based regimen we present is efficient and safe for salvage.
Assuntos
Anemia Aplástica , Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Humanos , Criança , Soro Antilinfocitário/uso terapêutico , Anemia Aplástica/genética , Anemia Aplástica/terapia , Condicionamento Pré-Transplante , Doença Enxerto-Hospedeiro/etiologia , Ciclofosfamida/uso terapêutico , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Antígenos HLA , Estudos RetrospectivosRESUMO
4-methylimidazole (4-MI) is an imidazole-derived organic chemical compound that can be used as a raw material in the manufacture of diverse chemicals and has been identified as an ingredient of caramel color in soybean sauce, beers, and other soft drinks. The aim of the present study was to investigate the teratogenic effects of 4-MI during zebrafish embryogenesis. Zebrafish embryos were treated with different dosages of 4-MI (0-120 mM) for different exposure durations (12-60 hours). The percentages of embryos with malformed phenotypes increased as the exposure dosages and duration time of 4-MI increased. We also used immunofluorescence and transmission microscopy to evaluate the subtle changes in the myofibril alignment and ultrastructure of muscle organization. Our data showed that 4-MI treatment disturbs muscle fiber alignment. Electron microscopy data indicated that Z-lines were undetectable in the 4-MI-treated embryos. Although the thick and thin filaments were visible, they were all disorganized. In addition, zebrafish embryos treated by 4-MI exhibited aberrant expression of 2 muscle-specific genes, myod and myogenin. Taken together, we concluded that early exposure to 4-MI affects zebrafish myogenesis, especially in myofibril alignment.
Assuntos
Desenvolvimento Embrionário/efeitos dos fármacos , Imidazóis/toxicidade , Desenvolvimento Muscular/efeitos dos fármacos , Miofibrilas/efeitos dos fármacos , Peixe-Zebra/embriologia , Animais , Embrião não Mamífero/efeitos dos fármacos , Miofibrilas/fisiologia , Proteínas de Peixe-Zebra/metabolismoRESUMO
The objective of the current study was to investigate the effects of Ca(2+) levels on myofibril alignment during zebrafish embryogenesis. To investigate how altered cytoplasmic Ca(2+) levels affect myofibril alignment, we exposed zebrafish embryos to 2-aminothoxyldiphenyl borate (2-APB; an inositol 1,4,5-trisphosphate receptor inhibitor that reduces cytosolic Ca(2+) levels) and caffeine (a ryanodine receptor activator that enhances cytosolic Ca(2+) levels). The results demonstrated that the most evident changes in zebrafish embryos treated with 2-APB were shorter body length, curved trunk and malformed somite boundary. In contrast, such malformed phenotypes were evident neither in untreated controls nor in caffeine-treated embryos. Subtle morphological changes, including changes in muscle fibers, F-actin and ultrastructures were easily observed by staining with specific monoclonal antibodies (F59 and α-laminin), fluorescent probes (phalloidin) and by transmission electron microscopy. Our data suggested that: (1) the exposure to 2-APB and/or caffeine led to myofibril misalignment; (2) 2-APB-treated embryos displayed split and short myofibril phenotypes, whereas muscle fibers from caffeine-treated embryos were twisted and wavy; and (3) zebrafish embryos co-exposed to 2-APB and caffeine resulted in normal myofibril alignment. In conclusion, we proposed that cytosolic Ca(2+) is important for myogenesis, particularly for myofibril alignment.
Assuntos
Compostos de Boro/toxicidade , Cafeína/toxicidade , Cálcio/metabolismo , Citosol/efeitos dos fármacos , Desenvolvimento Muscular/efeitos dos fármacos , Miofibrilas/efeitos dos fármacos , Peixe-Zebra/embriologia , Animais , Citosol/metabolismo , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/metabolismo , Embrião não Mamífero/ultraestrutura , Microscopia Eletrônica de Transmissão , Miofibrilas/ultraestruturaRESUMO
BACKGROUND: Hepatocellular carcinoma (HCC) is a malignancy with poor survival outcome. New treatment options for the disease are needed. In this study, we identified and evaluated tumor vascular PLVAP as a therapeutic target for treatment of HCC. METHODS: Genes showing extreme differential expression between paired human HCC and adjacent non-tumorous liver tissue were investigated. PLVAP was identified as one of such genes with potential to serve as a therapeutic target for treatment of HCC. A recombinant monoclonal anti-PLVAP Fab fragment co-expressing extracellular domain of human tissue factor (TF) was developed. The potential therapeutic effect and toxicity to treat HCC were studied using a Hep3B HCC xenograft model in SCID mice. RESULTS: PLVAP was identified as a gene specifically expressed in vascular endothelial cells of HCC but not in non-tumorous liver tissues. This finding was confirmed by RT-PCR analysis of micro-dissected cells and immunohistochemical staining of tissue sections. Infusion of recombinant monoclonal anti-PLVAP Fab-TF into the main tumor feeding artery induced tumor vascular thrombosis and extensive tumor necrosis at doses between 2.5 µg and 12 µg. Tumor growth was suppressed for 40 days after a single treatment. Systemic administration did not induce tumor necrosis. Little systemic toxicity was noted for this therapeutic agent. CONCLUSIONS: The results of this study suggest that anti-PLVAP Fab-TF may be used to treat HCC cases for which transcatheter arterial chemoembolization (TACE) is currently used and potentially avoid the drawback of high viscosity of chemoembolic emulsion for TACE to improve therapeutic outcome. Anti-PLVAP Fab-TF may become a viable therapeutic agent in patients with advanced disease and compromised liver function.
Assuntos
Anticorpos Monoclonais/uso terapêutico , Carcinoma Hepatocelular/química , Carcinoma Hepatocelular/tratamento farmacológico , Proteínas de Transporte/análise , Células Endoteliais/química , Neoplasias Hepáticas/química , Neoplasias Hepáticas/tratamento farmacológico , Proteínas de Membrana/análise , Animais , Anticorpos Monoclonais/efeitos adversos , Antígenos de Superfície/imunologia , Carcinoma Hepatocelular/genética , Proteínas de Transporte/genética , Proteínas de Transporte/imunologia , Células Endoteliais/metabolismo , Feminino , Xenoenxertos , Humanos , Fígado/química , Neoplasias Hepáticas/genética , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/imunologia , Camundongos , Camundongos SCID , Terapia de Alvo Molecular , RNA Mensageiro/metabolismo , Proteínas Recombinantes/imunologiaRESUMO
The aim of this study was to investigate the in vivo toxicities of some novel synthetic chalcones. Chalcone and four chalcone analogues 1a-d were evaluated using zebrafish embryos following antibody staining to visualize their morphological changes and muscle fiber alignment. Results showed that embryos treated with 3'-hydroxychalcone (compound 1b) displayed a high percentage of muscle defects (96.6%), especially myofibril misalignment. Ultrastructural analysis revealed that compound 1b-treated embryos displayed many muscle defect phenotypes, including breakage and collapse of myofibrils, reduced cell numbers, and disorganized thick (myosin) and thin (actin) filaments. Taken together, our results provide in vivo evidence of the myotoxic effects of the synthesized chalcone analogues on developing zebrafish embryos.
Assuntos
Anormalidades Induzidas por Medicamentos/patologia , Chalcona/análogos & derivados , Chalcona/toxicidade , Fibras Musculares Esqueléticas/patologia , Teratogênicos/toxicidade , Animais , Embrião não Mamífero/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Fibras Musculares Esqueléticas/efeitos dos fármacos , Músculo Esquelético/anormalidades , Peixe-ZebraRESUMO
D-serine is a well-known activator of N-methyl-D-aspartate receptors; however, little is known about the teratogenic effects of D-serine overdose during early embryonic development. Here, we used zebrafish as a model to test toxicity and teratogenicity, since they have transparent eggs, making the organogenesis of zebrafish embryos easier to be observed. After D-serine injection (100-1000 ppm), the most evident defective phenotypes were bent trunk phenotypes, including malformed somite boundary, twisted body axis and shorter body length. As the injection dosages increased, the rates of embryos with bent trunk phenotypes decreased (0% for 0 ppm, n=573; 59.9~84.3% for 100-1000 ppm of D-serine, n=383-451). In addition, D-serine-injected embryos exhibited significantly reduced the frequencies of spontaneous in-chorion contraction (21.7 for 0 ppm vs. 18.3-0.9 for 100-1000 ppm D-serine, n=30) in comparison with mock-treated controls (0 ppm). Subtle changes are easily observed by staining with specific monoclonal antibodies F59, Znp1, Zn5 and α-bungarotoxin to detect morphological changes in muscle fibers, primary motor axons, secondary motor axon projections and neuromuscular junctions, respectively. Our data show that overdose of D-serine leads to misalignment of muscle fibers and motor neuron defects, especially secondary motor neuron axonal growth defects.
RESUMO
Coumarin is a natural compound that is rich in plants. Coumarin and its derivates were reported to have many biological activities, such as anti-bacterial, anti-tumor, and anti-coagulation. In this study, we examined the angiogenic modulating activities of six previously synthesized coumarin derivatives (Compound #1-#6) in zebrafish embryos and further confirmed them in a chick model. According to the survival rate in a zebrafish model, Compound #1 (100 %), #2 (82.5-100 %), and #4 (100 %) showed much less toxicity than Compound #3 (19.2-100 %), #5 (0-100 %), and #6 (0-100 %). Using a green blood vessel fluorescent transgenic fish Tg(fli1:egfp) to record the angiogenesis-modulating effects of Compound #1, #2, and #4, we found that Compound #2 had the highest effects in interfering intersegmental vessel growth, subintestinal vein growth, and caudal vein plexus remodeling. Chick chorioallantoic membrane (CAM) assay also showed that Compound #2 exposure led to a reduction of blood vessel growth. Real-time PCR experiments revealed that Compound #2 significantly changed the expression of vascular growth-related genes flt1, cdh5, and nrp1a in zebrafish. Based on our data from zebrafish and chick models, a new coumarin-derivative (Compound #2) possesses anti-angiogenic activity with low toxicity, but further investigation in mammal models is asked to confirm our findings.
Assuntos
Angiogênese , Peixe-Zebra , Animais , Bioensaio , Galinhas , Cumarínicos/farmacologia , MamíferosRESUMO
The aim of this study was to investigate novel chalcones with potent anti-inflammatory activities in vivo. Chalcone and two chalcone analogues (compound 5 and 9) were evaluated using a caudal fin-wounded transgenic zebrafish line "Tg(mpx:gfp)" to visualize the effect of neutrophil recruitment dynamically. Results showed that treatment with compound 9 not only affected wound-induced neutrophil recruitment, but also affected Mpx enzymatic activity. Moreover, protein expression levels of pro-inflammatory factors (Mpx, NFκB, and TNFα) were also regulated by compound 9. Taken together, our results provide in vivo evidence of the anti-inflammatory effects of synthesized chalcone analogues on wound-induced inflammation.
Assuntos
Anti-Inflamatórios/farmacologia , Chalcona/análogos & derivados , Chalcona/farmacologia , Peixe-Zebra/metabolismo , Nadadeiras de Animais/cirurgia , Animais , Anti-Inflamatórios/síntese química , Anti-Inflamatórios/química , Chalcona/síntese química , Chalcona/química , Larva/efeitos dos fármacos , Larva/enzimologia , Modelos Animais , Infiltração de Neutrófilos/efeitos dos fármacos , Peroxidase/metabolismo , Cicatrização/efeitos dos fármacosRESUMO
Despite its medical use, little is known about the mechanisms underlying amikacin-induced embryotoxicity, including fin reduction, in zebrafish. In this study, we examined the expression of well-known autophagy markers mTOR (target of rapamycin), atg10 (autophagy-related gene), atg12 and LC3 (mammalian homolog of Atg8) in amikacin-treated zebrafish embryos. Our results indicated that the mRNA expression level of atg12 in the amikacin-treated group was significantly increased by 1.5-fold (p<0.05) compared with the corresponding mock control group, while the expression levels of atg10 and mTOR were significantly decreased by 0.74-fold (p<0.05) and 0.58-fold (p<0.05), respectively. Western blot analysis revealed that LC3 protein expression was induced by amikacin. Taken together, these data suggest that amikacin-induced fin reduction is mediated by fin cell autophagy.
RESUMO
Caffeine is a widely consumed substance that occurs in numerous dietary sources, but teratogenic effects of caffeine intake during embryonic development are still not clear. In the present study, we used the zebrafish as a model to assess caffeine-induced toxicity on embryonic vascular development. A green fluorescent vascular endothelium transgenic line, Tg(fli1:egfp), was utilized for the sensitive detection of vascular development, including vasculo- and angiogenesis. Caffeine-treated embryos showed no defects in vasculogenesis, but revealed dose-dependent (250-350 ppm) developmental defects in intersegmental vessels, dorsal longitudinal anastomotic vessels, and subintestinal vein sprouting. Further, real-time polymerase chain reaction analysis of caffeine-treated embryos showed an upregulation of nrp1a along with a downregulation of sema3aa and sema3c. In conclusion, caffeine treatment induces defects of angiogenesis in zebrafish embryos.
Assuntos
Cafeína/toxicidade , Endotélio Vascular/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Proteínas de Peixe-Zebra/efeitos dos fármacos , Animais , Animais Geneticamente Modificados , Cafeína/administração & dosagem , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/metabolismo , Endotélio Vascular/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Fatores de Crescimento Neural/efeitos dos fármacos , Fatores de Crescimento Neural/genética , Reação em Cadeia da Polimerase em Tempo Real , Teratogênicos/toxicidade , Regulação para Cima/efeitos dos fármacos , Peixe-Zebra/embriologia , Proteínas de Peixe-Zebra/genéticaRESUMO
We used zebrafish as a model to assess amikacin-induced embryotoxicity. We exposed zebrafish embryos to amikacin, using different amikacin doses (0-10 ppm), durations (12-48 h), and onsets (0, 24, 48 hpf). Amikacin-induced embryonic toxicity and reduced survival rate were found dependent on the exposure dose, duration and onset. Based on immunostaining with neuron-specific antibodies, amikacin reduced the number and size of zebrafish neuromasts. In addition, Amikacin caused pelvic, dorsal and anal fin defects in dose-dependent and duration-dependent manners. Proliferating cell nuclear antigen immunostaining revealed that amikacin-induced fin defects were not due to reduction of proliferating mesenchymal cells. TUNEL assay demonstrated that amikacin-induced fin defects might not associate with apoptosis. Therefore, further investigations are required to elucidate if other cell death pathways are involved in amikacin-induced fin defects.
Assuntos
Anormalidades Induzidas por Medicamentos/etiologia , Amicacina/toxicidade , Nadadeiras de Animais/anormalidades , Antibacterianos/toxicidade , Animais , Apoptose/efeitos dos fármacos , Relação Dose-Resposta a Droga , Embrião não Mamífero/efeitos dos fármacos , Peixe-ZebraRESUMO
Capsulin is one of the transcription factors involved in regulating cell differentiation but its biochemical properties and structural characteristics are still unclear. In the present study, we cloned capsulin from zebrafish, which produces large numbers of transparent embryos and has well-characterized developmental stages. By alignment, the deduced amino acid sequence of zebrafish Capsulin, which contains a putative bHLH motif, shares very high homology to that of other species with an 72-82% identity. Zebrafish Capsulin was also targeted to the nucleus of mammalian cells when overexpressed by transient transfection. In order to characterize the structural and biochemical properties of zebrafish Capsulin, a recombinant zebrafish Capsulin protein was expressed and purified in Escherichia coli. By circular dichroism spectroscopy, Capsulin was shown to be 55% α-helical. The size distribution assay by analytical ultracentrifugation indicated that it existed as a monomer-dimer mixture. The results suggested that the recombinant Capsulin has a well-organized and functional structure. Finally, endogenous Capsulin was distributed mainly in the epicardial cells of zebrafish by immunohistochemistry analysis using antibodies raised against zebrafish Capsulin. The present study not only helps us to comparatively analyze capsulin genes across species, but it also provides valuable structural information for further studies of Capsulin biological function in the future.
Assuntos
Escherichia coli/genética , Fatores de Transcrição/análise , Fatores de Transcrição/genética , Proteínas de Peixe-Zebra/análise , Proteínas de Peixe-Zebra/genética , Peixe-Zebra/genética , Sequência de Aminoácidos , Animais , Anticorpos/imunologia , Linhagem Celular , Núcleo Celular/ultraestrutura , Clonagem Molecular , DNA Complementar/genética , Expressão Gênica , Humanos , Dados de Sequência Molecular , Pericárdio/citologia , Conformação Proteica , Multimerização Proteica , Proteínas Recombinantes/análise , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Alinhamento de Sequência , Fatores de Transcrição/química , Fatores de Transcrição/isolamento & purificação , Transfecção , Proteínas de Peixe-Zebra/química , Proteínas de Peixe-Zebra/isolamento & purificaçãoRESUMO
The objective of this study was to investigate the embryotoxicity of diclofenac. Zebrafish (Danio rerio) embryos at 12 hpf were treated with different dosages of diclofenac (0-2,000 ppm) for different time courses (12-72 hr). Results showed no evident differences in survival rates or morphological changes between the mock-treated control (0 ppm) zebrafish embryos and those with 1-ppm diclofenac-exposure (12-24, 12-36 hpf). In contrast, after higher doses (5 and 10 ppm) of exposure, embryos displayed some defective phenotypes, including malformed somite boundary, a twisted body axis, and shorter body length. In addition, diclofenac-treated embryos exhibited significantly reduced frequencies of spontaneous in-chorion contractions in comparison with mock-control littermates (mock-control: 13.20 ± 2.24 vs. 5-10 ppm diclofenac: 6.66 ± 1.35-3.03 ± 1.84). Subtle changes were easily observed by staining with specific monoclonal antibodies F59 and phalloidin to detect morphological changes in muscle fibers and formation of F-actin, respectively. Our data show that diclofenac treatment disturbs actin organization and muscle fiber alignment, thus causing malformed somite phenotypes.
Assuntos
Actinas/efeitos dos fármacos , Diclofenaco/toxicidade , Embrião não Mamífero/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Miofibrilas/efeitos dos fármacos , Peixe-Zebra/embriologia , Actinas/metabolismo , Animais , Embrião não Mamífero/anormalidades , Modelos Lineares , Modelos Logísticos , Miofibrilas/metabolismo , Miofibrilas/patologia , Fenótipo , Somitos/efeitos dos fármacos , Somitos/patologia , Peixe-Zebra/anormalidadesRESUMO
This study applied broccoli and cauliflower extracts (whole, floret, and stem) to zebrafish larvae in parallel to receive 100 mJ/cm(2) of UVB six times, and recorded their fin malformation phenotypes. Chemopreventive effects of each group, including UVB, whole-, floret-, and stem-extracts of broccoli and cauliflower on fin development were evaluated using Kaplan-Meier analysis, log-rank test, and Cox proportional hazards regression. Results showed that (1) zebrafish fins in the UVB + whole broccoli extract group are 6.20~9.32-times more likely to return to normal fins than ones in the UVB only group, but fins in the UVB + whole cauliflower extract group are only 5.13~11.10-times more likely to recover, indicated that whole broccoli and cauliflower extract had similar chemopreventive ability on fin development; and (2) the broccoli stem has the highest antioxidant capacity among other groups. In conclusion, zebrafish can be used as a system for evaluating the efficacy of other UVB protective compounds.
Assuntos
Nadadeiras de Animais/efeitos da radiação , Brassica/química , Extratos Vegetais/farmacologia , Raios Ultravioleta , Animais , Larva/efeitos dos fármacos , Extratos Vegetais/química , Peixe-Zebra/embriologiaRESUMO
(1) Background: Amikacin is an aminoglycoside antibiotic used for treating gram-negative bacterial infections in cancer patients. In this study, our aims are to investigate the migratory inhibition effects of amikacin in human MDA-MB-231 cells. (2) Methods: We used a wound-healing assay, trans-well analysis, Western blotting, immunostaining and siRNA knockdown approaches to investigate how amikacin influenced MDA-MB-231 cell migration and invasion. (3) Results: Wound healing showed that the MDA-MB-231 cell migration rates decreased to 44.4% in the presence of amikacin. Trans-well analysis showed that amikacin treatment led to invasion inhibition. Western blotting demonstrated that amikacin induced thioredoxin-interacting protein (TXNIP) up-regulation. TXNIP was knocked down using siRNA in MDA-MB-231 cell. Using immunostaining analysis, we found that inhibition of TXNIP expression led to MDA-MB-231 pseudopodia extension; however, amikacin treatment attenuated the cell extension formation. (4) Conclusions: We observed inhibition of migration and invasion in MDA-MB-231 cells treated with amikacin. This suggests inhibition might be mediated by up-regulation of TXNIP.
RESUMO
We generated a transgenic line Tg(k18:shh:RFP) with overexpression of Sonic hedgehog in the skin epidermis. By 5 day-post-fertilization (dpf), many epidermal lesions were clearly observed, including a swollen yolk sac, epidermis growth malformation around the eyes and at the basement of the pectoral fins. Skin histology revealed embryos derived from Tg(k18:shh:RFP) displayed an elevated Nuclear/Cytoplasmic ratio and pleomorphic nuclei compared to their wild type littermates, suggesting the abnormal growth pattern on the epidermis of Tg(k18:shh:RFP) embryos were dysplasia. Later (by 7 dpf), Tg(k18:shh:RFP) embryos displayed broader pectoral fins which are similar to the polydactyly phenotypes of Nevoid basal cell carcinoma syndrome (NBCCS)/Gorlin patients and polydactylous mice. In addition, treatment with cyclopamine is able to enhance and prolong the survival rates and survival durations of Tg(k18:shh:RFP) embryos. In conclusion, this unique Tg(k18:shh:RFP) fish line, should be an excellent experimental animal for screening for a lower toxicity level of the new Hh-inhibitor and can even be used as a new anti-cancer drug-screening platform.
Assuntos
Carcinoma Basocelular/tratamento farmacológico , Embrião não Mamífero/metabolismo , Proteínas Hedgehog/antagonistas & inibidores , Proteínas Hedgehog/genética , Pele/metabolismo , Peixe-Zebra/genética , Animais , Animais Geneticamente Modificados/metabolismo , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Queratina-18/genética , Proteínas Luminescentes/genética , Pele/citologia , Teratogênicos , Alcaloides de Veratrum , Peixe-Zebra/embriologiaRESUMO
Though caffeine is broadly distributed in many plants and foods, little is known about the teratogenic effects of caffeine during early embryonic development. Here, we used zebrafish as a model to test toxicity and teratogenicity since they have transparent eggs, making the organogenesis of zebrafish embryos easier to observe. When the exposure doses of caffeine were less than 150 ppm (17.5, 35, 50, 100 and 150 ppm), the zebrafish embryos exhibited no significant differences in survival rates after comparison with vehicle-control (0 ppm) group. As the exposure dosages increased, the survival rates decreased. No embryos survived after treatment with 300 ppm caffeine or higher dosages. The most evident change in embryos treated with caffeine was a shorter body length (vehicle-control: 3.26+/-0.01 mm, n=49; vs 150 ppm of caffeine: 2.67+/-0.03 mm, n=50). In addition, caffeine-treated embryos exhibited significantly reduced tactile sensitivity frequencies of touch-induced movement (vehicle-control: 9.93+/-0.77 vs 17.5-150 ppm caffeine: 5.37+/-0.52-0.10+/-0.06). Subtle changes are easily observed by staining with specific monoclonal antibodies F59, Znp1 and Zn5 to detect morphological changes in muscle fibers, primary motor axons and secondary motor axon projections, respectively. Our data show that the treatment of caffeine leads to misalignment of muscle fibers and motor neuron defects, especially secondary motor neuron axonal growth defects.
Assuntos
Cafeína/toxicidade , Discinesia Induzida por Medicamentos/fisiopatologia , Embrião não Mamífero/efeitos dos fármacos , Neurônios Motores/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Medula Espinal/efeitos dos fármacos , Animais , Anticorpos Monoclonais , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Discinesia Induzida por Medicamentos/patologia , Embrião não Mamífero/anormalidades , Desenvolvimento Embrionário/efeitos dos fármacos , Desenvolvimento Embrionário/fisiologia , Neurônios Motores/patologia , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares Esqueléticas/patologia , Músculo Esquelético/anormalidades , Músculo Esquelético/inervação , Junção Neuromuscular/anormalidades , Junção Neuromuscular/efeitos dos fármacos , Junção Neuromuscular/fisiopatologia , Inibidores de Fosfodiesterase/toxicidade , Transtornos de Sensação/induzido quimicamente , Transtornos de Sensação/patologia , Transtornos de Sensação/fisiopatologia , Medula Espinal/anormalidades , Taxa de Sobrevida , Fatores de Tempo , Testes de Toxicidade , Peixe-ZebraRESUMO
BACKGROUND: Myf5 is one member of the basic helix-loop-helix family of transcription factors, and it functions as a myogenic factor that is important for the specification and differentiation of muscle cells. The expression of myf5 is somite- and stage-dependent during embryogenesis through a delicate regulation. However, this complex regulatory mechanism of myf5 is not clearly understood. RESULTS: We isolated a 156-kb bacterial artificial chromosome clone that includes an upstream 80-kb region and a downstream 70-kb region of zebrafish myf5 and generated a transgenic line carrying this 156-kb segment fused to a green fluorescent protein (GFP) reporter gene. We find strong GFP expression in the most rostral somite and in the presomitic mesoderm during segmentation stages, similar to endogenous myf5 expression. Later, the GFP signals persist in caudal somites near the tail bud but are down-regulated in the older, rostral somites. During the pharyngula period, we detect GFP signals in pectoral fin buds, dorsal rostral myotomes, hypaxial myotomes, and inferior oblique and superior oblique muscles, a pattern that also corresponds well with endogenous myf5 transcripts. To characterize the specific upstream cis-elements that regulate this complex and dynamic expression pattern, we also generated several transgenic lines that harbor various lengths within the upstream 80-kb segment. We find that (1) the -80 kb/-9977 segment contains a fin and cranial muscle element and a notochord repressor; (2) the -9977/-6213 segment contains a strong repressive element that does not include the notochord-specific repressor; (3) the -6212/-2938 segment contains tissue-specific elements for bone and spinal cord; (4) the -2937/-291 segment contains an eye enhancer, and the -2937/-2457 segment is required for notochord and myocyte expression; and (5) the -290/-1 segment is responsible for basal transcription in somites and the presomitic mesoderm. CONCLUSION: We suggest that the cell lineage-specific expression of myf5 is delicately orchestrated by multiple modules within the distal upstream region. This study provides an insight to understand the molecular control of myf5 and myogenesis in the zebrafish.
Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Fator Regulador Miogênico 5/genética , Proteínas de Peixe-Zebra/genética , Peixe-Zebra/genética , Animais , Animais Geneticamente Modificados/genética , Clonagem Molecular , Regiões Promotoras Genéticas , Fatores Estimuladores Upstream/genética , Peixe-Zebra/embriologiaRESUMO
Sodium benzoate (SB) is a commonly used food preservative and anti-microbial agent in many foods from soup to cereals. However, little is known about the SB-induced toxicity and teratogenicity during early embryonic development. Here, we used zebrafish as a model to test the toxicity and teratogenicity because of their transparent eggs; therefore, the organogenesis of zebrafish embryos is easy to observe. After low dosages of SB (1-1000 ppm) treatment, the zebrafish embryos exhibited a 100% survival rate. As the exposure dosages increased, the survival rates decreased. No embryos survived after treatment with 2000 ppm SB. The 50% lethal dose (LD(50)) of zebrafish is found to be in the range of 1400-1500 ppm. Gut abnormalities, malformation of pronephros, defective hatching gland and edema in pericardial sac were observed after treatment with SB. Compared to untreated littermates (vehicle-treated control), SB-treated embryos exhibited significantly reduced tactile sensitivity frequencies of touch-induced movement (vehicle-treated control: 27.60+/-1.98 v.s. 1000 ppm SB: 7.89+/-5.28; N=30). Subtle changes are easily observed by staining with specific monoclonal antibodies F59, Znp1 and alpha6F to detect morphology changes in muscle fibers, motor axons and pronephros, respectively. Our data showed that the treatment of SB led to misalignment of muscle fibers, motor neuron innervations, excess acetyl-choline receptor cluster and defective pronephric tubes. On the basis of these observations, we suggest that sodium benzoate is able to induce neurotoxicity and nephrotoxicity of zebrafish larvae.