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Free Radical Biology & Medicine Apr 2022EPR spectroscopy is a technique that provides direct information about free radicals in biological systems. So far, X-band EPR was seldomly used for in vivo studies as...
EPR spectroscopy is a technique that provides direct information about free radicals in biological systems. So far, X-band EPR was seldomly used for in vivo studies as the small resonator size and high power used to detect EPR signals were unsuitable for living organisms. Here, we report new solutions which lift some limitations and make X-band EPR suitable for an in vivo detection of free radicals in zebrafish - a small laboratory animal that is often used as a model for various studies related to free radicals. We designed specially-shaped glass and quartz capillaries to ensure the zebrafish's safety during the experiments. The optimal EPR spectrometer parameters, safe for zebrafish embryos and sufficient to obtain EPR spectrum, were 4 scans by 20s, 100G sweep, and 0.8 mW power. Combining the specially-shaped capillary with a multi-harmonic analyzer for the EPR spectrometer allowed increasing the time up to 16 scans by 11s and lowering the power to 0.25 mW. As a proof of principle, we demonstrate the detection of melanin radicals and the 5-DSA spin probe in zebrafish larvae. As fish survive the EPR scans, the possibility of performing multiple measurements of free radicals in living zebrafish offers new tools for studies aiming to understand redox biology and membrane-dependent functions in both health and disease.
Topics: Animals; Electron Spin Resonance Spectroscopy; Free Radicals; Melanins; Nitrogen Oxides; Zebrafish
PubMed: 35314357
DOI: 10.1016/j.freeradbiomed.2022.03.015 -
Blood Feb 2012Although platelets are the smallest cells in the blood, they are implied in various processes ranging from immunology and oncology to thrombosis and hemostasis. Many... (Review)
Review
Although platelets are the smallest cells in the blood, they are implied in various processes ranging from immunology and oncology to thrombosis and hemostasis. Many large-scale screening programs, genome-wide association, and "omics" studies have generated lists of genes and loci that are probably involved in the formation or physiology of platelets under normal and pathologic conditions. This creates an increasing demand for new and improved model systems that allow functional assessment of the corresponding gene products in vivo. Such animal models not only render invaluable insight in the platelet biology, but in addition, provide improved test systems for the validation of newly developed anti-thrombotics. This review summarizes the most important models to generate transgenic platelets and to study their influence on platelet physiology in vivo. Here we focus on the zebrafish morpholino oligonucleotide technology, the (platelet-specific) knockout mouse, and the transplantation of genetically modified human or murine platelet progenitor cells in myelo-conditioned mice. The various strengths and pitfalls of these animal models are illustrated by recent examples from the platelet field. Finally, we highlight the latest developments in genetic engineering techniques and their possible application in platelet research.
Topics: Animals; Animals, Genetically Modified; Blood Platelets; Gene Transfer Techniques; Humans; Mice; Models, Animal; Models, Biological; Platelet Transfusion; Thrombopoiesis; Zebrafish
PubMed: 22180441
DOI: 10.1182/blood-2011-10-381715 -
Proceedings. Biological Sciences Dec 2022The remarkable similarities in cognitive performance between teleosts and mammals suggest that the underlying cognitive mechanisms might also be similar in these two...
The remarkable similarities in cognitive performance between teleosts and mammals suggest that the underlying cognitive mechanisms might also be similar in these two groups. We tested this hypothesis by assessing the effects of the brain-derived neurotrophic factor (BDNF), which is critical for mammalian cognitive functioning, on fish's cognitive abilities. We found that individual differences in zebrafish's learning abilities were positively correlated with expression. Moreover, a CRISPR/Cas9 mutant zebrafish line that lacks the BDNF gene () showed remarkable learning deficits. Half of the mutants failed a colour discrimination task, whereas the remaining mutants learned the task slowly, taking three times longer than control zebrafish. The mutants also took twice as long to acquire a T-maze task compared to control zebrafish and showed difficulties exerting inhibitory control. An analysis of habituation learning revealed that cognitive impairment in mutants emerges early during development, but could be rescued with a synthetic BDNF agonist. Overall, our study indicates that BDNF has a similar activational effect on cognitive performance in zebrafish and in mammals, supporting the idea that its function is conserved in vertebrates.
Topics: Animals; Brain-Derived Neurotrophic Factor; Zebrafish; Individuality; Cognition; Mammals
PubMed: 36541170
DOI: 10.1098/rspb.2022.2036 -
British Journal of Pharmacology Oct 2003The zebrafish has recently emerged as an important model for the study of vascular embryogenesis. Its genetic accessibility, external development, and optically clear... (Review)
Review
The zebrafish has recently emerged as an important model for the study of vascular embryogenesis. Its genetic accessibility, external development, and optically clear embryo are just a few of the features that set the zebrafish apart as a particularly well-suited model for studying vascular development. However, there is little precedent for its use as a tool for the experimental study of therapeutic angiogenesis. Here, we review the use of the zebrafish for studying vascular development and patterning, and discuss how the zebrafish might be used more directly as a model for developing and testing effective therapeutic angiogenesis approaches.
Topics: Angiogenesis Inducing Agents; Animals; Blood Vessels; Drug Design; Drug Evaluation, Preclinical; Models, Animal; Zebrafish
PubMed: 14534143
DOI: 10.1038/sj.bjp.0705496 -
Biochimica Et Biophysica Acta Sep 2013The incidence of diseases increases rapidly with age, accompanied by progressive deteriorations of physiological functions in organisms. Aging-associated diseases are... (Review)
Review
The incidence of diseases increases rapidly with age, accompanied by progressive deteriorations of physiological functions in organisms. Aging-associated diseases are sporadic but mostly inevitable complications arising from senescence. Senescence is often considered the antithesis of early development, but yet there may be factors and mechanisms in common between these two phenomena over the dynamic process of aging. The association between early development and late-onset disease with advancing age is thought to come from a consequence of developmental plasticity, the phenomenon by which one genotype can give rise to a range of physiologically and/or morphologically adaptive states in response to different environmental or genetic perturbations. On the one hand, we hypothesized that the future aging process can be predictive based on adaptivity during the early developmental period. Modulating the thresholds of adaptive plasticity by chemical genetic approaches, we have been investigating whether any relationship exists between the regulatory mechanisms that function in early development and in senescence using the zebrafish (Danio rerio), a small freshwater fish and a useful model animal for genetic studies. We have successfully conducted experiments to isolate zebrafish mutants expressing apparently altered senescence phenotypes during embryogenesis ("embryonic senescence"), subsequently showing shortened lifespan in adulthoods. We anticipate that previously uncharacterized developmental genes may mediate the aging process and play a pivotal role in senescence. On the other hand, unexpected senescence-related genes might also be involved in the early developmental process and regulation. The ease of manipulation using the zebrafish system allows us to conduct an exhaustive exploration of novel genes and small molecular compounds that can be linked to the senescence phenotype, and thereby facilitates searching for the evolutionary and developmental origins of aging in vertebrates. This article is part of a Special Issue entitled: Animal Models of Disease.
Topics: Aging; Animals; Disease Models, Animal; Humans; Zebrafish
PubMed: 23660559
DOI: 10.1016/j.bbadis.2013.04.030 -
Future Medicinal Chemistry Sep 2012Due to several inherent advantages, zebrafish are being utilized in increasingly sophisticated screens to assess the physiological effects of chemical compounds directly... (Review)
Review
Due to several inherent advantages, zebrafish are being utilized in increasingly sophisticated screens to assess the physiological effects of chemical compounds directly in living vertebrate organisms. Diverse screening platforms showcase these advantages. Morphological assays encompassing basic qualitative observations to automated imaging, manipulation, and data-processing systems provide whole organism to subcellular levels of detail. Behavioral screens extend chemical screening to the level of complex systems. In addition, zebrafish-based disease models provide a means of identifying new potential therapeutic strategies. Automated systems for handling/sorting, high-resolution imaging and quantitative data collection have significantly increased throughput in recent years. These advances will make it easier to capture multiple streams of information from a given sample and facilitate integration of zebrafish at the earliest stages of the drug-discovery process, providing potential solutions to current drug-development bottlenecks. Here we outline advances that have been made within the growing field of zebrafish chemical screening.
Topics: Animals; Behavior, Animal; Drug Discovery; High-Throughput Screening Assays; Luminescent Proteins; Zebrafish
PubMed: 23043478
DOI: 10.4155/fmc.12.115 -
Blood Apr 2008After a decade of the "modern era" of zebrafish hematology research, what have been their major contributions to hematology and what challenges does the model face? This... (Review)
Review
After a decade of the "modern era" of zebrafish hematology research, what have been their major contributions to hematology and what challenges does the model face? This review argues that, in hematology, zebrafish have demonstrated their suitability, are proving their utility, have supplied timely and novel discoveries, and are poised for further significant contributions. It presents an overview of the anatomy, physiology, and genetics of zebrafish hematopoiesis underpinning their use in hematology research. Whereas reverse genetic techniques enable functional studies of particular genes of interest, forward genetics remains zebrafish's particular strength. Mutants with diverse and interesting hematopoietic defects are emerging from multiple genetic screens. Some mutants model hereditary blood diseases, occasionally leading to disease genes first; others provide insights into developmental hematology. Models of malignant hematologic disorders provide tools for drug-target and pharmaceutics discovery. Numerous transgenic zebrafish with fluorescently marked blood cells enable live-cell imaging of inflammatory responses and host-pathogen interactions previously inaccessible to direct observation in vivo, revealing unexpected aspects of leukocyte behavior. Zebrafish disease models almost uniquely provide a basis for efficient whole animal chemical library screens for new therapeutics. Despite some limitations and challenges, their successes and discovery potential mean that zebrafish are here to stay in hematology research.
Topics: Animals; Biomedical Research; Disease Models, Animal; Drug Delivery Systems; Genetic Diseases, Inborn; Hematologic Diseases; Hematology; Hematopoiesis; History, 20th Century; History, 21st Century; Host-Pathogen Interactions; Humans; Inflammation; Leukocytes; Zebrafish
PubMed: 18182572
DOI: 10.1182/blood-2007-10-052761 -
Toxicologic Pathology 2003The zebrafish (Danio rerio) is now the pre-eminent vertebrate model system for clarification of the roles of specific genes and signaling pathways in development. The... (Review)
Review
The zebrafish (Danio rerio) is now the pre-eminent vertebrate model system for clarification of the roles of specific genes and signaling pathways in development. The zebrafish genome will be completely sequenced within the next 1-2 years. Together with the substantial historical database regarding basic developmental biology, toxicology, and gene transfer, the rich foundation of molecular genetic and genomic data makes zebrafish a powerful model system for clarifying mechanisms in toxicity. In contrast to the highly advanced knowledge base on molecular developmental genetics in zebrafish, our database regarding infectious and noninfectious diseases and pathologic lesions in zebrafish lags far behind the information available on most other domestic mammalian and avian species, particularly rodents. Currently, minimal data are available regarding spontaneous neoplasm rates or spontaneous aging lesions in any of the commonly used wild-type or mutant lines of zebrafish. Therefore, to fully utilize the potential of zebrafish as an animal model for understanding human development, disease, and toxicology we must greatly advance our knowledge on zebrafish diseases and pathology.
Topics: Animals; Animals, Genetically Modified; Carcinogenicity Tests; Carcinogens, Environmental; Models, Animal; Pathology; Toxicology; Zebrafish
PubMed: 12597434
DOI: 10.1080/01926230390174959 -
Scientific Reports Dec 2021Trrap (transformation/transcription domain-associated protein) is a component shared by several histone acetyltransferase (HAT) complexes and participates in...
Trrap (transformation/transcription domain-associated protein) is a component shared by several histone acetyltransferase (HAT) complexes and participates in transcriptional regulation and DNA repair; however, the developmental functions of Trrap in vertebrates are not fully understood. Recently, it has been reported that human patients with genetic mutations in the TRRAP gene show various symptoms, including facial dysmorphisms, microcephaly and global developmental delay. To investigate the physiological functions of Trrap, we established trrap gene-knockout zebrafish and examined loss-of-function phenotypes in the mutants. The trrap zebrafish mutants exhibited smaller eyes and heads than the wild-type zebrafish. The size of the ventral pharyngeal arches was reduced and the mineralization of teeth was impaired in the trrap mutants. Whole-mount in situ hybridization analysis revealed that dlx3 expression was narrowly restricted in the developing ventral pharyngeal arches, while dlx2b expression was diminished in the trrap mutants. These results suggest that trrap zebrafish mutants are useful model organisms for a human disorder associated with genetic mutations in the human TRRAP gene.
Topics: Adaptor Proteins, Signal Transducing; Animals; Gene Expression Regulation; Nuclear Proteins; Zebrafish; Zebrafish Proteins
PubMed: 34934055
DOI: 10.1038/s41598-021-03123-z -
Developmental Cell Nov 2003Establishing a network of blood vessels has been, for more reasons than one, an exciting field of research. In Development, Isogai et al. now describe in unprecedented...
Establishing a network of blood vessels has been, for more reasons than one, an exciting field of research. In Development, Isogai et al. now describe in unprecedented resolution the dynamic process of angiogenesis in the trunk of the zebrafish embryo.
Topics: Animals; Cardiovascular System; Diagnostic Imaging; Neovascularization, Physiologic; Recombinant Fusion Proteins; Zebrafish
PubMed: 14602067
DOI: 10.1016/s1534-5807(03)00334-4