Objective: To investigate the toxicity of tris (2-chloropropyl) phosphate (TCIPP) and tributyl phosphate (TnBP) on the growth and development of zebrafish embryos, as well as to explore the underlying mechanisms at the transcriptional level. Methods: With zebrafish as a model, two hpf zebrafish embryos were exposed to TCIPP and TnBP (0.1, 1, 10, 100, 500, and 1 000 μmol/L) using the semi-static method, and their rates of lethality and hatchability were determined. The transcriptome changes of 120 hpf juvenile zebrafish exposed to environmentally relevant concentrations of 0.1 and 1 μmol/L were measured. Results: The 50% lethal concentrations (LC₅₀) of TCIPP and TnBP for zebrafish embryos were 155.30 and 27.62 μmol/L (96 hpf), 156.5 and 26.05 μmol/L (120 hpf), respectively. The 72 hpf hatching rates of TCIPP (100 μmol/L) and TnBP (10 μmol/L) were (23.33±7.72)% and (91.67±2.97)%, which were significantly decreased compared with the control group (P<0.05). Transcriptome analysis showed that TnBP had more differential genes (DEGs) than TCIPP, with a dose-response relationship. These DEGs were enriched in 32 pathways in total, including those involved in oxidative stress, energy metabolism, lipid metabolism, and nuclear receptor-related pathways, using the IPA pathway analysis. Among them, three enriched pathways overlapped between TCIPP and TnBP, including TR/RXR activation and CAR/RXR activation. Additionally, DEGs were also mapped onto pathways of LXR/RXR activation and oxidative stress for TnBP exposure only. Conclusion: Both TCIPP and TnBP have growth and developmental toxicities in zebrafish embryos, with distinct biomolecular mechanisms, and TnBP has a stronger effect than TCIPP.
Animals ; Zebrafish/metabolism* ; Embryo, Nonmammalian/metabolism* ; Transcriptome ; Oxidative Stress ; Water Pollutants, Chemical/metabolism*

Animals ; Embryo, Nonmammalian ; drug effects ; metabolism ; Ethanol ; toxicity ; RNA, Messenger ; metabolism ; Resveratrol ; pharmacology ; Zebrafish ; Zebrafish Proteins ; metabolism

The use of exogenous carbon monoxide releasing molecules (CORMs) provides promise for clinical application; however, the hazard potential of CORMs in vivo remains poorly understood. The developmental toxicity of CORM-3 was investigated by exposure to concentrations ranging from 6.25 to 400 μmol/L during 4-144 h post fertilization. Toxicity endpoints of mortality, spontaneous movement, heart rate, hatching rate, malformation, body length, and larval behavior were measured. CORM-3 disrupted the progression of zebrafish larval development at concentrations exceeding 50 μmol/L, resulting in embryonic developmental toxicity.
Animals ; Carbon Monoxide ; pharmacology ; Cardiotonic Agents ; toxicity ; Dose-Response Relationship, Drug ; Embryo, Nonmammalian ; drug effects ; Embryonic Development ; drug effects ; Organometallic Compounds ; toxicity ; Zebrafish ; embryology ; metabolism

OBJECTIVETo perform the genetic identification of cloche(172) mutant zebrafish.

METHODSThe chemical mutagen N-ethyl-N-nitrosourea (ENU) was used to treat the AB stain male fish. Large-scale forward genetic screening was carried out to search for lyC-deficient zebrafish mutant by WISH. The morphology changes of the embryos at 3 days postfertilization (3dpf) stage were observed and the cloche(172) gene was identified by mapping and complementation test.

RESULTSWe selected 4 lyC-deficient zebrafish by WISH. cloche(172) mutant showed morphological changes similar to cloche mutant in 3dpf stage. One fourth of the embryos showed cloche phenotype as found in complementation test, and the cloche(172) gene was mapped on the telomere of zebrafish 13 chromosome where cloche gene was located. Numerous red blood cells were observed in the cloche(172) mutant, while only a few cells were found in the cloche mutant in the tail region by o-dianisdine staining.

CONCLUSIONcloche(172) gene which is responsible for the phenotype of cloche mutant may be a novel point mutation allele of the cloche mutant.

Alleles ; Animals ; Chromosome Mapping ; Cloning, Molecular ; Embryo, Nonmammalian ; embryology ; metabolism ; Ethylnitrosourea ; toxicity ; Genetic Complementation Test ; Male ; Muramidase ; genetics ; Mutation ; Zebrafish ; embryology ; genetics ; Zebrafish Proteins ; genetics

OBJECTIVE1-Bromo-3-chloro-5,5-dimethylhydantoin (BCDMH) is a solid oxidizing biocide for water disinfection. The objective of this study was to investigate the toxic effect of BCDMH on zebrafish.

METHODSThe developmental toxicity of BCDMH on zebrafish embryos and the dose-effect relationship was determined. The effect of BCDMH exposure on histopathology and tissue antioxidant activity of adult zebrafish were observed over time.

RESULTSExposure to 4 mg/L BCDMH post-fertilization was sufficient to induce a number of developmental malformations, such as edema, axial malformations, and reductions in heart rate and hatching rate. The no observable effects concentration of BCDMH on zebrafish embryo was 0.5 mg/L. After 96 h exposure, the 50% lethal concentration (95% confidence interval (CI)) of BCDMH on zebrafish embryo was 8.10 mg/L (6.15-11.16 mg/L). The 50% inhibitory concentration (95% CI) of BCDMH on hatching rate was 7.37 mg/L (6.33-8.35 mg/L). Histopathology showed two types of responses induced by BCDMH, defensive and compensatory. The extreme responses were marked hyperplasia of the gill epithelium with lamellar fusion and epidermal peeling. The histopathologic changes in the gills after 10 days exposure were accompanied by significantly higher catalase activity and lipid peroxidation.

CONCLUSIONThese results have important implications for studies on the toxicity and use of BCDMH and its analogs.

Animals ; Antioxidants ; metabolism ; Disinfectants ; toxicity ; Dose-Response Relationship, Drug ; Embryo, Nonmammalian ; drug effects ; Hydantoins ; toxicity ; Time Factors ; Water ; chemistry ; Water Pollutants, Chemical ; toxicity ; Zebrafish

Zebrafish is widely used as a model organism in the process of drug discovery. It expresses drug metabolizing enzymes like cytochrome P450 (CYP450), uridine 5'-diphospho-glucuronosyltransferase (UGT) and nuclear receptors like pregnane X receptor (PXR), aryl hydrocarbon receptor (AHR), etc. This article summarized the profiles of main drug metabolizing enzymes and nuclear receptors, and reviewed the advances on xenobiotics metabolism in zebrafish.
Animals ; Cytochrome P-450 Enzyme System ; metabolism ; Embryo, Nonmammalian ; drug effects ; Glucuronosyltransferase ; metabolism ; Inactivation, Metabolic ; Pharmaceutical Preparations ; metabolism ; Polychlorinated Dibenzodioxins ; toxicity ; Receptors, Aryl Hydrocarbon ; metabolism ; Receptors, Cytoplasmic and Nuclear ; metabolism ; Receptors, Steroid ; metabolism ; Teratogens ; toxicity ; Xenobiotics ; metabolism ; Zebrafish ; embryology ; metabolism

OBJECTIVETo investigate the mechanism of retinoic acid (RA) signal in dental evolution, RA is used to explore the influence of the mechanism on neural crest's migration during the early stage of zebra fish embryos.

METHODSWe divided embryos of wild type and transgenic line zebra fish into three groups. 1 x 10(-7) to 6 x 10(-7) mol x L(-1) RA and 1 x 10(-7) mo x L(-1) 4-diethylaminobenzaldehyde (DEAB) were added into egg water at 24 hpf for 9 h. Dimethyl sulfoxid (DMSO) with the concentration was used as control group. Then, antisense probes of dlx2a, dlx2b, and barxl were formulated to perform whole-mount in situ hybridization to check the expressions of the genes in 48 hpf to 72 hpf embryos. We observed fluorescence of transgenic line in 4 dpf embryos.

RESULTSWe obtained three mRNA probes successfully. Compared with DMSO control group, a low concentration (1 x 10(-7) mol x L(-1)) of RA could up-regulate the expression of mRNA (barx1, dlx2a) in neural crest. Obvious migration trend was observed toward the pharyngeal arch in which teeth adhered. Transgenic fish had spreading fluorescence tendency in pharyngeal arch. However, a high concentration (4 x 10(-7) mol x L(-1)) of RA malformed the embryos and killed them after treatment. One third of the embryos of middle concentration (3 x 10(-7) mo x L(-1)) exhibited delayed development. DEAB resulted in neural crest dysplasia. The expression of barxl and dlx2a were suppressed, and the appearance of dlx2b in tooth was delayed.

CONCLUSIONRA signal pathway can regulate the progenitors of tooth by controlling the growth of the neural crest and manipulating tooth development

Animals ; Branchial Region ; Cell Differentiation ; drug effects ; Embryo, Nonmammalian ; drug effects ; embryology ; metabolism ; In Situ Hybridization ; Neural Crest ; drug effects ; Odontogenesis ; Signal Transduction ; Tooth ; drug effects ; embryology ; metabolism ; Tretinoin ; pharmacology ; Zebrafish ; embryology ; genetics ; metabolism

To investigate the effect ofgene down-regulation on early hematopoietic development of zebrafish.Phosphorodiamidate morpholino oligomer (PMO) technology was used to downregulategene expression in Zebrafish. Zebrafish embryos injected phosphorodiamidate morpholino antisense oligonucleotide ofgene mRNA by microinjection at unicellular stage were taken as the experimental group, and those injected meaningless phosphorodiamidate morpholino antisense oligonucleotide were taken as the control. The embryos were collected at 18, 24, 30 and 36 hpf after the fertilization. The real-time fluorescent quantitative PCR (RT-PCR) and whole embryohybridization methods were used to detect the expression of myeloid hematopoietic transcription factorand erythroid hematopoietic transcription factorin zebrafish.RT-PCR showed that the expressions ofanddecreased in the experimental group compared with the control group (all<0.05). Whole embryohybridization showed that the blue-black positive hybridization signals ofandin experimental group were shallow than those in the control group.Myeloid hematopoietic and erythroid hematopoietic of zebrafish are blocked with the downregulation ofgene.
Animals ; Down-Regulation ; genetics ; Embryo, Nonmammalian ; physiopathology ; GATA1 Transcription Factor ; genetics ; metabolism ; Gene Knockdown Techniques ; Hematopoiesis ; In Situ Hybridization ; Lamin Type A ; genetics ; physiology ; Proto-Oncogene Proteins ; genetics ; metabolism ; Trans-Activators ; genetics ; metabolism ; Zebrafish ; embryology ; genetics

Pdx-1, an important transcription factor highlighting in the early pancreatic development, islet functions and pancreatic disorders, needs to be more investigated in zebrafish, and siRNA is still seldom applied in zebrafish embryo-related research. Our aim was to explore the role of pdx-1 in pancreatic development of zebrafish embryos by using siRNA approach. Microinjection, reverse transcriptase-PCR (RT-PCR), in situ hybridization and immunofluorescent staining were used in this research, and the morphology of the islet in normal zebrafish embryos, and in those treated with the siRNA specific to pdx-1 (siPDX-1) or siGFP was observed and compared. The expression of pdx-1 was detected in the stages of 1-cell, 2-cell, 4-cell, 8-cell, 16-cell, 16-hour by RT-PCT. The in situ hybridization and immunofluorescent staining results showed that siPDX-1 disturbed the formation of the islet in zebrafish embryos. Pdx-1 played multiple roles in maintaining the phenotype of the islet during embryogenesis in zebrafish.
Embryo, Nonmammalian ; Homeodomain Proteins/genetics ; Homeodomain Proteins/*metabolism ; Islets of Langerhans/cytology ; Islets of Langerhans/*embryology ; Islets of Langerhans/metabolism ; RNA Interference ; RNA, Small Interfering/*genetics ; Trans-Activators/genetics ; Trans-Activators/*metabolism ; Zebrafish

Lidamycin (LDM) is a potent antitumor antibiotic. Previous studies have shown that LDM could inhibit proliferation and migration in endothelial cells. In the present report, the effect of LDM on angiogenesis of zebrafish embryo was studied. The results showed that treatment of zebrafish embryos with LDM resulted in significant inhibition of angiogenesis. Morphological observation, quantitative endogenous alkaline phosphatase (EAP) assay, alkaline phosphatase staining, and transgenic zebrafish assay were performed to evaluate vascular development defects in zebrafish. The results indicated that after the zebrafish embryos were exposed to LDM, angiogenesis defects of zebrafish embryos were observed, including pericardial edema, reduced numbers of circulating red blood cells, suppression of zebrafish vessel growth, and absences of SIV (subintestinal vein). The expression of VEGF was detected by RT-PCR assay, quantitative reverse transcriptase real-time PCR (qRT-PCR) assay and Western blotting analysis. The results revealed that LDM could inhibit the expression of VEGF protein, while the expression of mRNA was not significantly affected. The study suggests that LDM could inhibit the zebrafish embryo angiogenesis by down-regulation ofVEGF expression.
Aminoglycosides ; pharmacology ; Animals ; Animals, Genetically Modified ; embryology ; genetics ; physiology ; Antibiotics, Antineoplastic ; pharmacology ; Down-Regulation ; Embryo, Nonmammalian ; drug effects ; Enediynes ; pharmacology ; Neovascularization, Physiologic ; drug effects ; genetics ; RNA, Messenger ; metabolism ; Vascular Endothelial Growth Factor A ; genetics ; metabolism ; Zebrafish ; embryology ; genetics ; physiology