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The impact of SIRT1 inhibition on zebrafish morphology and behavior
Faustová, Zuzana ; Červený, Lukáš (advisor) ; Mladěnka, Přemysl (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Zuzana Faustová Supervisor: Prof. Doutor Jorge Miguel de Ascenção Oliveira PharmDr. Lukáš Červený, Ph.D. Title of diploma thesis: The impact of SIRT1 inhibition on zebrafish morphology and behavior After discovery of connection between yeast Silent Information Regulator 2 (Sir2) and its ability to alter lifespan, Sir2 and its seven mammalian orthologs became very attractive therapeutic target. These so called sirtuins are members of a histone deacetylase family. They possess unique catalytic activity having nicotinamide adenine dinucleotide as a cofactor and their function can be influenced by environmental factors. The aim of this diploma thesis was to extend knowledge of Sirtuin 1 (SIRT1), which is from all mammalian sirtuins considered to have the closest relation to yeast Sir2. At first we tested the impact of SIRT1 inhibition on early developmental stages of zebrafish (Danio rerio) embryos and larvae, finding out that SIRT1 is important for normal development and SIRT1 inhibition or malfunction result in cardiovascular defects, delayed development, and death. Additionally, we tried to learn more about SIRT1 and its connection with Parkinson's disease by combining nontoxic doses...
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Regeneration of heart muscle in vertebrates
Bergelová, Barbora ; Krylov, Vladimír (advisor) ; Mašek, Jan (referee)
Fish model organisms such a Danio rerio have the ability to regenerate heart muscle during its whole lifespan. Compared to Danio rerio, the ability of heart regeneration differs in amphibians. While the newt has the ability to regenerate its heart tissue throughout its whole life, the Xenopus leavis loses its power when it goes through metamorphosis. The regenerative ability varies not only between genera but also between species. For example compared to Xenopus leavis, Xenopus tropicalis has the ability to regenerate its heart tissue even in adulthood. Mammals have a very limited ability to regenerate their heart muscle. We can observe the ability to regenerate heart after injury in mice and humans for a very limited time of a few days after birth. In adulhood the heart is healed via rich collagen scar. It is vital that signaling pathways in highly regenerative model organisms are intensively studied, so that the knowledge gained may help us in the treatment of heart injuries in humans. Key words: regeneration, heart muscle, repair, zebrafish, mammals, amphibians, heart development, vertebrates
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Regeneration of heart muscle in vertebrates
Bergelová, Barbora ; Krylov, Vladimír (advisor) ; Mašek, Jan (referee)
The model organisms like for example the fish Danio rerio has the ability to regenerate heart muscle during its whole lifespan. Compared to Danio rerio, the ability of heart regeneration differs in amphibians. While the newt has the ability to regenerate its heart tissue throughout its whole life, the Xenopus leavis loses its power when it goes through metamorphosis. The regenerative ability does not only differ between salamanders and claws. We can observe some differences between regeneration of Xenopus tropicalis and Xenopus leavis too. Compared to Xenopus leavis, Xenopus tropicalis has the ability to regenerate its heart tissue even in adulthood. Mammals have a very limited ability to regenerate their heart muscle. We can observe the ability to reverse heart damage in mice and humans for a very limited time of a few days after they are born. In adulhood they repair the heart muscle and the rich collagen scar is formed. It is vital that signaling pathways in regeneration of model organisms is researched further, so that the knowledge gained may help us in the treatment of heart injuries in humans. Key words: regeneration, heart muscle, repair, zebrafish, mammals, amphibians, heart development, vertebrates
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Hematopoiesis in the models of zebrafish and medaka as a recipient for human HSC xenograft
Pravcová, Naďa ; Drbal, Karel (advisor) ; Svoboda, Ondřej (referee)
Danio rerio (zebrafish) and Oryzias latipes (medaka) have recently become popular model organisms to study hematopoiesis. These model organisms present several advantages in comparison to other commonly used models, the most common being Mus musculus (mouse). The advantages are shorter generation time, large offspring production, frequent spawning, external fertilization and development, the optical transparency of embryos amenable to genetic manipulation on the background of vast numbers of transgenic lines (mainly in zebrafish) and inbred strains (in medaka). Moreover, most of the mechanisms behind zebrafish and medaka hematopoiesis are conserved in higher vertebrates. Most importantly, the optical transparency in early development and in adult mutant transparent strains allows for observation of hematopoietic stem cell (HSC) development in vivo. Therefore, it is possible to generate humanized fish using xenotransplanted human HSCs for studies of the engraftment, differentiation, and trafficking of human HSC in vivo. Currently, the most popular organism for human HSC xenotransplantation is mice. This model system is not suitable for in vivo imaging of HSC engraftment. Moreover, a prior immunodepletion step is necessary. The process of immunodepletion includes genetic manipulation or irradiation...
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Zebrafish as a model to study the glutamate receptor mediated excitatory neurotrasmission
Chumchal, Lukáš ; Balík, Aleš (advisor) ; Pangrácová, Marie (referee)
Glutamate is the most prominent excitatory neurotransmitter in the vertebrate brain and is used by most synaptic connections in the cortex. Signal transduction on these neurons is mediated by ionotropic glutamate receptors, including the NMDA receptor family. With the development of molecular biological methods and the advent of genomics, genetic changes found in ionotropic glutamate receptors were tested, as well as substances that modulate their activity. Since a large number of genetic changes found, rodents have ceased to be a sufficiently robust system for some, for example, behavioural studies. In these types of studies, the model organism Danio rerio could replace rodents. The use of this model organism could thus expand knowledge about the evolution and physiology of glutamate receptors. This work aims to summarize the current knowledge about the use of Dania rerio in the research of glutamate receptors, especially NMDA type in the central nervous system. This work also focuses on the description of specific behavioural tests available for the analysis of these receptors.
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Anaemia disease models
Vondráková, Zuzana ; Bartůněk, Petr (advisor) ; Stopka, Tomáš (referee)
Hematopoiesis is a process by which blood cells are generated. All vertebrates have two phases of hematopoiesis - primitive and definitive. The main purpose of primitive hematopoiesis is the production of red blood cells, which provide oxygenation to the developing embryo. Other blood cell lineages are established by definitive hematopoiesis. The main function of erythrocytes is oxygen transport to all tissues. When erythrocyte production is decreased or they are damaged due to the membrane, enzyme or hemoglobin impairment, the condition called anemia arises. Sickle cell disease and β-thalassemia are called hemoglobinopathies as they are caused by the damaged hemoglobin. Fanconi anemia is caused by mutations in one of 21 genes of Fanconi anemia pathway, which plays an essential role in DNA repair. Diamond Blackfan anemia is caused by mutations gene for ribosomal proteins. Human cells, Mus musculus, Gallus gallus, Xenopus laevis and Danio rerio seem to be good models for study of this diseases and they are also useful for achieving therapeutical goals.
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The impact of SIRT1 inhibition on zebrafish morphology and behavior
Faustová, Zuzana ; Červený, Lukáš (advisor) ; Mladěnka, Přemysl (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Zuzana Faustová Supervisor: Prof. Doutor Jorge Miguel de Ascenção Oliveira PharmDr. Lukáš Červený, Ph.D. Title of diploma thesis: The impact of SIRT1 inhibition on zebrafish morphology and behavior After discovery of connection between yeast Silent Information Regulator 2 (Sir2) and its ability to alter lifespan, Sir2 and its seven mammalian orthologs became very attractive therapeutic target. These so called sirtuins are members of a histone deacetylase family. They possess unique catalytic activity having nicotinamide adenine dinucleotide as a cofactor and their function can be influenced by environmental factors. The aim of this diploma thesis was to extend knowledge of Sirtuin 1 (SIRT1), which is from all mammalian sirtuins considered to have the closest relation to yeast Sir2. At first we tested the impact of SIRT1 inhibition on early developmental stages of zebrafish (Danio rerio) embryos and larvae, finding out that SIRT1 is important for normal development and SIRT1 inhibition or malfunction result in cardiovascular defects, delayed development, and death. Additionally, we tried to learn more about SIRT1 and its connection with Parkinson's disease by combining nontoxic doses...
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Origins of vertebrate hematiopoiesis
Svoboda, Ondřej ; Bartůněk, Petr (advisor) ; Divoký, Vladimír (referee) ; Živný, Jan (referee)
(ENGLISH) Hematopoiesis is dependent on the actions of hematopoietic stem cells (HSCs). This process is tightly controlled through a complex array of extrinsic and intrinsic factors. Even though the hematopoiesis seems to be well conserved across the disparate vertebrate animals, erythroid and thrombocytic differentiation have changed during the evolution of mammals. Specifically, adult mammalian red blood cells have the unique feature of being enucleated, and mammalian thrombocytes are not individual cells, but fragments of megakaryocytes, instead. It is likely that these enhancements provided a survival advantage to early mammalian species; however, they also bring up the question of evolutionary origin of these cells that studied using zebrafish (Danio rerio) model. First, it was necessary to generate a toolbox of a recombinant cytokines and optimized culture media that allowed us to manipulate zebrafish hematopoietic cells ex vivo in liquid and clonal cultures. Interestingly, teleost species underwent an extra duplication event during their evolution and as a result, two copies (paralogs) of some of the genes are present in zebrafish. This was also the case for majority of the cytokines from our toolbox and here, we provide functional characterization of these paralogs. Strikingly, our results...
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