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Novel bile acid derivatives as a promising therapeutic approach for liver and metabolic disorders
Štefela, Alžbeta ; Pávek, Petr (advisor) ; Vítek, Libor (referee) ; Juřica, Jan (referee)
IN ENGLISH LANGUAGE Charles University, Faculty of Pharmacy in Hradec Králové, Department of Pharmacology and Toxicology Candidate: Mgr. Alžbeta Štefela Supervisor: Prof. PharmDr. Petr Pávek, PhD. Title of the doctoral thesis: Novel bile acid derivatives as promising therapeutic approach Bile acids (BAs) are amphipathic steroidal molecules that are traditionally known to facilitate intestinal digestion and absorption of lipids and fat-soluble substances. On top, the recent findings have revealed that they represent important signaling agents involved in the orchestration of lipid, glucose and energy metabolism and immune response. BAs exhibit these roles by activating intracellular nuclear receptors such as farnesoid X (FXR), pregnane X (PXR) vitamin D receptors. Furthermore, BAs act as endocrine signaling molecules and activate numerous biological cascades via a membrane G-protein-coupled receptor, termed TGR5. Therefore, the extensive modulation of BA scaffold underwent to identify compounds with specific targeting of above-mentioned receptors as a promising therapeutic approach for the treatment of various liver and metabolic disorders including cholestasis, biliary cirrhosis, nonalcoholic steatohepatitis or diabetes. The principal aim of this doctoral thesis was to investigate the structure...
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Quantum optical nanosensors for microRNA
Čopák, Jakub ; Cígler, Petr (advisor) ; Ménová, Petra (referee)
Several disease processes taking place in the cells are characterized by an increase of the concentration of nucleic acids, in particular micro RNAs (miRNAs). A detection system that could selectively detect the increased presence of the miRNAs directly in the living cells in real time with nanoresolution is therefore highly desired. Fluorescent nanodiamond particles are considered promising candidates thanks to their biocompatibility, small size, allowing them to penetrate the cell membrane, and stable fluorescent defects in the crystal lattice, namely nitrogen-vacancy (NV) centres. The NV centres are the most studied colour centres of nanodiamonds due to their unique room-temperature optical properties, allowing for highly sensitive detection of changes in the magnetic field (magnetic noise) with quantum sensing techniques. For instance, the length of the T1 relaxation time NV electronic spin is greatly influenced by the presence of paramagnetic species, which causes a shortening of the T1 relaxation time depending on the proximity to the NV centres. However, for selective quantum sensing with nanodiamonds, the use of molecular transducers is necessary to bind targeted molecules with high specificity and allow their detection via the change of the NV spin properties. In this work,...
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The use of "omics" methods in molecular-epidemiologic study in newborns from different localities of the Czech Republic
Hoňková, Kateřina ; Rössner, Pavel (advisor) ; Gábelová, Alena (referee) ; Bláha, Luděk (referee)
The "omics" is a concept of biological disciplines that globally characterizes and quantifies biomolecules involved in the key functions of an organism. The "omics" methods are used e.g. in molecular epidemiology, where they help to evaluate potential biomarkers that identify the impact of environmental factors for human health. In this thesis, the "omics" methods were applied in samples collected from newborns born in localities of the Czech Republic mostly differing by pollution levels from industrial sources. The principal aim was to determine whether environmental changes during prenatal development can affect gene expression and its regulation in newborns. The thesis further aimed to evaluate the level of air pollution at the time of biological samples collection. Using the whole genome approach, differentially expressed genes (DEGs) in newborns from districts Karvina and Ceske Budejovice (CB) were identified. In a pilot study of a small group of newborns from districts Most and CB, differentially methylated CpG sites in DNA were assessed. These sites attenuate gene activity and could be responsible for long-term changes at the genetic level. Finally, the aim was to find differentially expressed small non-coding RNA (DE miRNA) in newborns from Most and CB. Samples of umbilical cord blood from...
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Postpartal expression profile of cardiovascular microRNAs with regard to occurrence of pregnancy-related complications - study on mothers 3-10 years after the delivery
Marvanová, Veronika ; Hromadníková, Ilona (advisor) ; Korabečná, Marie (referee)
The aim of this study was to investigate gene expression of cardiovascular miRNAs in peripheral blood of mothers after delivery. MiRNAs are small non-coding RNAs, which significantly modulate posttranscriptional adjustments of mRNA and thus regulate gene expression across biological processess. Dysregulation of miRNAs is associated with many pathological phenomena, thanks that we can use them for diagnosis and potentionaly we can treat these diseases by the manipulation of miRNA gene expression. We examined gene expression of circulating miRNAs associated with cardiovascular diseases, and we investigated, how the expression profile depends on pregnancy course and manifestation of pregnancy-related complications. For this purpose we examined material from 221 mothers 3-10 years after delivery. A group with identical pregnancy-related complication was always compared with a group of mothers after physiological pregnancy. Gene expression of 29 cardiovascular miRNAs in peripheral blood was studied using reverse transcription and quantitative real-time PCR. It was confirmed, that the expression profile of miRNAs differed between pregnancy-related complications and physiological controls. We also confirmed, that the profile of gene expression discovered at mothers 3-10 years after delivery was different...
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lncRNA MIAT expression in cancer cells.
Jursová, Pavlína ; Eckschlager, Tomáš (advisor) ; Sztacho, Martin (referee)
LncRNAs have been shown, in many cases, to function as important regulators for gene expression and thus, they can play a critical role in various biological functions and disease processes including cancer. Myocardial infarction associated transcript (MIAT) is one of the non-coding RNAs first identified as lncRNA in 2006 and originally isolated as a candidate gene for myocardial infarction. This long non-coding RNA is also involved in other diseases such as diabetic retinopathy, paranoid schizophrenia or microvascular dysfunction. MIAT has also been identified as a carcinogenic regulator in many malignant tumors. Numerous researches have reported that MIAT silencing reduces cell viability, proliferation and invasivity and enhances cellular senescence and apoptosis of cancer cells. Therefore, it is considered a potential biomarker and therapeutic target in cancer. MIAT is involved in cellular processes through various mechanisms. It regulates alternative splicing, gene expression or functions through ceRNA mechanism and thus influences biological processes related to the tumor formation. Furthermore, in this study have been found that relative expression of MIAT was increased in Ewing sarcoma cell lines.
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Formation of spatio-temporal molecular gradients in early embryonic development of Xenopus laevis.
Flachsová, Monika
Clarifying the underlying spatio-temporal mechanisms that determine body pattern is important for detailed understanding of embryonic development. A crucial question of vertebrate embryogenesis remains: when and how are single blastomeres determined for differentiation that subsequently leads to body axes specification and the formation of different tissues and organs? The answer to this question will be beneficial for primary research as well as in the field of applied medicine. The main aim of the presented thesis was to study spatio-temporal molecular gradients of cell fate determinants during early embryonic development. The African clawed frog Xenopus laevis was used as a model organism because of their large size of oocytes and external embryonic development. Due to late activation of embryonic transcription, a crucial mechanism of early blastomeres determination is dependent on asymmetric localization of maternal factors within oocyte and their uneven distribution into single blastomeres during early cell division. Two main localization patterns were identified along the animal-vegetal axis of the mature Xenopus oocyte using qPCR tomography. The localization gradient with preference in either animal or vegetal hemisphere was found for maternal mRNA as well as miRNAs. Moreover, two vegetal...
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The expression of miRNA in HPV-associated and HPV-independent head and neck tumors
Vojtěchová, Zuzana
Head and neck cancers represent a group of tumors with two different etiologies. The first type is associated with the viral HPV infection, the second one is virus-independent and it is associated with smoking and alcohol consumption as two main risk factors. Numerous studies show that HPV-positive tumors are more frequent in younger patients, as well as that the prognosis and overall survival of these patients is remarkably better. Therefore, the modification of the treatment is considered. For this, however, specific, sensitive and clinically relevant biomarkers for accurate identification of tumor etiology is needed. Suitable candidates for such biomarkers are miRNAs, small non-coding regulatory molecules stable in archived samples, that have been shown as differentially expressed in human cancers and the expression pattern seems specific for tumors of different origin. The submitted thesis focuses on miRNA profiling in HPV-positive and HPV-negative tonsillar tumors and cervical carcinomas with the aim to find out the differences between regulation of important carcinogenetic pathways of tumors of viral and non-viral etiology. Our data have shown very large heterogeneity of the miRNA expression profiles of these tumors. Despite the well characterized and uniform samples collection, we have found...
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Molecular aspects of musculoskeletal diseases and the role of small regulatory RNAs
Pleštilová, Lenka ; Vencovský, Jiří (advisor) ; Šedivá, Anna (referee) ; Hrnčíř, Zbyněk (referee)
Rheumatic diseases are common, usually chronic, painful and to some extent invalidating medical conditions. Understanding of the disease pathogenesis is still very fragmentary. Hyperreactivity of the immune system and defect of autotolerance are probably contributed by local factors, which helps to explain, why some joints/muscles are more affected than others. All this results from a complex net of interactions between immune cells, synovial fibroblasts, chondrocytes, osteocytes, myocytes and other cells. In the submitted PhD thesis I have focused on three groups of molecules: regulatory RNAs, S100 proteins and autoantibodies. In the theoretical part, I sum up the current knowledge on their biogenesis, function and the role in rheumatology. In the investigative part, I present six original publications and one review on the role of those molecules in development of rheumatoid arthritis (RA) and idiopathic inflammatory myositis (IIM). One of the main studies was focused on expression of PIWI-interacting RNAs (piRNAs) in RA synovial fibroblasts (SF). piRNAs are small regulatory RNAs which in complex with PIWIL proteins regulate gene expression and silence transpozoms. piRNA expression was considered to be limited to germline and cancer cells. We have found 267 PIWI-interacting RNAs to be expressed...
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The role of miRNA in injury and regeneration of spinal cord tissue
Šprincl, Vojtěch ; Romanyuk, Natalyia (advisor) ; Mrózková, Petra (referee)
MicroRNAs are small non-coding RNA molecules of a length about 20-24 nucleotides, that regulate gene expression post-transcriptionally. They interfere mRNA molecules via base- pairing with complementary sequences. Recently it was shown that they play an important role in injury and regeneration of nervous tissue. The aim of this bachelor thesis is to describe possible role of miRNAs in central nervous system injury with focus on spinal cord injury.
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Štúdium možností elektrochemickej detekcie špecifických sekvencií nukleových kyselín
Vaňová, Veronika
This work deals with the study of the possibility of creating an electrochemical biosensor for the detection of specific nucleic acid sequences. The theoretical part describes various types of RNA, with a special focus on miRNAs and possibilities of its detection. It also describes various electrochemical detection approaches, both nucleic acids, and more specifically miRNAs. miRNA is a potential biomarker that can be used for early and non-invasive diagnosis of cancer. The experimental part is aimed at designing, optimizing and preparing a sensitive biosensor for the detection of miRNA-21. A biosensor was prepared to detect the lowest concentration of miRNA-21 in the sample. A linear concentration range for the calibration curve from 1 nM to 1 µM concentration was measured. We measured LOD of 1 fM and by calculation from the regression equation to 3.2 zM and LOQ was 10.8 zM. Subsequently, samples were measured in artificial urine to verify the functioning of the sensor in real conditions. The results showed a minimal effect of the matrix on the determination of the target miRNA.
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