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Molecular basis of deficit of F1Fo-ATP synthase and its impact on energy metabolism of a cell
Štufková, Hana ; Tesařová, Markéta (advisor) ; Kuncová, Jitka (referee) ; Janovská, Petra (referee)
Mitochondria's primary function is to produce energy through the process of oxidative phosphorylation. ATP synthase is a macromolecular rotary machine located in the inner mitochondrial membrane that catalyzes the synthesis of adenosine triphosphate (ATP) from adenosine diphosphate (ADP) and inorganic phosphate (Pi). The mitochondrial disorders due to ATP synthase deficiency represent a heterogeneous group of diseases characterized by variable severity of the phenotype with onset at birth or later in life till adulthood. Mutations in both, mitochondrial or nucelar DNA encoded genes, may result in ATP synthase impairment, either isolated or combined with deficits of other complexes of oxidative phosphorylation. The aims of the thesis were to characterize TMEM70 protein, an ATP synthase assembly factor, and to analyze the impact of novel disease variants leading to ATP synthase deficiency in patients' derived samples. TMEM70 is a 21 kDa hairpin structure protein localized in the inner mitochondrial membrane, with both termini oriented into the matrix, which forms higher oligomer structures. Our results demonstrated that the absence of TMEM70 protein leads to an isolated deficiency of complex V followed in some stage by adaptive/compensatory effect of respiratory chain complexes. Different severities...
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Protein profiling, metabolic enzymes and transmembrane signaling in the heart of spontaneously hypertensive SHR-Tg19 rat
Manakov, Dmitry ; Novotný, Jiří (advisor) ; Kuncová, Jitka (referee) ; Kalous, Martin (referee)
Cardiovascular diseases account for the majority of deaths both worldwide and in the Czech Republic. Main factors contributing heart disease development, aside age and sex, are obesity, high blood pressure and high blood cholesterol and triglyceride levels. Spontaneously hypertensive rat (SHR) was developed and used for search of genetic determinants of these traits. This commonly used rat model develops hypertension, dyslipidemia, and insulin resistance naturally which is caused by aberrant Cd36 fatty acid translocase gene. Previous studies have shown that rescue of Cd36 performed in the transgenic SHR-Tg19 strain enhances cardiac beta-adrenergic system, slightly increases heart mass and leads to higher susceptibility to arrhythmias. The present thesis had two main aims: 1) To investigate whether and how a transgenic rescue of Cd36 in SHR affects protein composition, mitochondrial function and activity of selected metabolic enzymes of the heart. 2) To study the expression and distribution of selected components of beta-adrenergic signaling system in lipid raft isolated form membranes using the TX-100 detergent. We set to compare two commonly used proteomic approaches, 2D electrophoresis with MALDI-TOF mass spectrometry and label-free LC-MS. The results did not reveal any overlap between...
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Pharmacological and metabolic influence on liver mitochondrial functions
Sobotka, Ondřej ; Červinková, Zuzana (advisor) ; Kuncová, Jitka (referee) ; Žurmanová, Jitka (referee)
Liver mitochondria play a crucial role in intermediary metabolism and main metabolic pathways. We evaluated the pharmacological effect on liver mitochondria in vitro using two novel anticancer drugs: 3-bromopyruvate and α-tocopheryl succinate. Metabolic influence on liver mitochondria was performed in vivo by high fat and high cholesterol diet. Toxicity of both drugs was evaluated in cell cultures of hepatocytes isolated from rat and mouse liver. The effect of anticancer drugs on liver mitochondrial functions in vitro was studied on suspensions of isolated liver mitochondria, tissue homogenate and permeabilized hepatocytes. Mitochondrial respiration was measured using high-resolution respirometry. 3-bromopyruvate caused morphological and functional damage of primary rat and mouse hepatocytes in cell cultures; this toxic effect was accompanied by an increase of reactive oxygen species production and mitochondrial dysfunction. 3-bromopyruvate decreased the oxygen consumption of mitochondria energized by substrates for complex I and complex II. α-Tocopheryl succinate caused a decrease of succinate-dependent respiration in all experimental models both in coupled and in uncoupled states. The most pronounced effect of α-tocopheryl succinate was apparent in isolated mitochondria and the least pronounced...
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The Role of Cellular Metabolism in Carcinogenesis. Molecular Pathophysiology of Bladder Cancer Chemoresistance
Kripnerová, Michaela ; Kuncová, Jitka (advisor) ; Nevoral, Jan (referee) ; Chovanec, Miroslav (referee)
Therapeutic resistance of tumours represents an important clinical issue. We can classify the therapeutic tumour resistance in two ways. According to the clinical course, tumours can behave either as primary resistant, i.e. from the very beginning not responsive, or they can display a secondary (also called acquired) resistance, whereby an initial clinical response is lost and the tumour develops into chemo-, radio- or immunoresistant disease. An alternative classification distinguishes cell autonomous resistance mechanisms from resistance that relies on complex interactions within the context of tumour microenvironment. From the research perspective, modelling therapeutic resistance frequently involves experimental treatment of sensitive cancer cells and selection of daughter resistant cell lines. The Ph.D. thesis includes derivation of two unique models of urothelial bladder carcinoma therapeutic resistance. The first model involves newly established urothelial carcinoma cell lines BC44 and BC44DoxoR, which resulted from a prolonged doxorubicin exposure of the mother cell line. The daughter chemoresistant cell line exhibits multidrug resistant phenotype, which extends beyond the selecting drug - doxorubicin - to four additional chemotherapeutic drugs (cisplatin, methotrexate, vinblastine, and...
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The effects of stress on the periphery and in the central nervous system with respect to the role of muscarinic receptors
Vařejková, Eva ; Mysliveček, Jaromír (advisor) ; Kuncová, Jitka (referee) ; Bakoš, Ján (referee)
The aim of our work was to analyse the role of muscarinic M2 receptors (M2MRs) in the organism at rest and under stress. In the experiments, changes in animals with expressed M2MRs are compared with M2KO animals who lack these receptors. The heart rate (HR) is determined by the level of the sympathetic and parasympathetic tones, the resulting HR is being the interaction of adrenergic and cholinergic receptors, which are among the receptors attached to G proteins. Their activity is influenced by structures of the autonomic nervous system with the highest centers with integrative function in the hypothalamus. The organism responds to the absence of M2MRs by decreasing the number of adrenergic receptors; heart rate in resting conditions does not change significantly. However, in restraint stress, there are differences both during the stress response and in the post-stress period (more pronounced and prolonged tachycardia). The treatment with carbachol (MR agonist) in M2KO animals induced tachycardia, strongly suggesting the presence of cardioexcitatory MRs. Ultradian heart rate rhythm is the superstructure of the circadian rhythm controlled by the suprachiasmatic nucleus. Autonomous regulation can affect other hypothalamic functions - circadian rhythms, endocrine regulation, thermoregulation,...
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Expression of CD44 molecules in urothelial bladder cancer
Kuncová, Jitka ; Mandys, Václav (advisor) ; Smetana, Karel (referee) ; Hes, Ondřej (referee) ; Záťura, František (referee)
The main aim of presented work was to contribute to clarify the significance of changes in expression of adhesion molecules and CD44 in the malignant behavior of urothelial carcinomas of the urinary bladder. The individual stages to meet this goal were: 2.1 Detailed determination of expression of CD44s and CD44v6 protein in urothelial carcinomas of the urinary bladder in relation to the degree of tumor differentiation. 2.2 Determine the relationship of CD44 protein expression changes depending on the characteristics histomorphologic urothelial carcinoma of the urinary bladder, and other indicators of biological behavior of tumor (proliferative activity, p53 expression). 2.3 Evaluation of expression of CD44s and CD44v6 protein in two phenotypically distinct cell lines, urothelial carcinomas (HT1197 and 5637) and determine relationships CD44 expression on morphological and growth characteristics of tumor cells of these lines.
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Effect of Selected Pathological States on Mitochondrial Function in Mammalian Cells and Tissues
Kohoutová, Michaela ; Kuncová, Jitka (advisor) ; Červinková, Zuzana (referee) ; Ferko, Miroslav (referee)
Sepsis, or life-threatening organ dysfunction caused by deregulated host response to the presence of infection, is one of the most significant causes of death caused by infection diseases worldwide. 31.5 million patients get sick with sepsis annually and 5.3 million of them die. Sepsis is characterised by homeostatic dysbalance, which can lead to septic shock or even to death. Sepsis may also result in development of multiorgan dysfunction or damage to several organs at the same time. Especially heart, kidneys, liver, lungs, central nervous system and blood elements belong among the organs affected by sepsis. One of the most affected organs is the heart, impairment of which is accompanied with the development of myocardial depression, which contributes to the increase of mortality from sepsis. The precise mechanisms leading to septic myocardial depression have not been fully explained yet, nevertheless mitochondria appear to play an important role in this process. Due to sepsis, many mitochondrial functions are disrupted, which is subsequently manifested by the depletion of cellular energy stores, resulting in myocardial depression. In our laboratories, we managed to create a clinically relevant model of sepsis and septic shock, specifically sepsis caused by fecal peritonitis in domestic pigs, that...
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Regulace receptorů spřažených s G proteiny Studie muskarinových a β-adrenergních receptorů u M2KO myší
Beneš, Jan ; Mysliveček, Jaromír (advisor) ; Kuncová, Jitka (referee) ; Nováková, Marie (referee)
(in English): The aim of the work was to perform in-depth analysis of M2KO mice both at baseline and upon a challenge with a cold stress and to explore the role of opposing receptors (i.e. adrenoceptors) in adaptation to lacking M2-receptors in the heart. We have performed receptor binding studies, study of receptor gene expression, echocardiography, telemetric monitoring of heart rate, body temperature and activity, heart rate variability and biorhythm analysis, analysis of heart rate response to the application of drugs (carbachol, atropine, isoprenaline, propranolol), assessment of adenylyl cyclase and NO synthase activity, measurement of catecholamine blood concentration and gene expression of catecholamine-synthesizing enzymes. We have found that the disruption of M2-receptor gene caused a compensatory decrease of cardiostimulatory β1-adrenoceptors and β2-adrenoceptors with corresponding down-regulation of the gene expression, M3-receptors were down-regulated as well. Missing M2-receptors were functionally replaced by the main cardioinhibitory β3-adrenoceptors that were up-regulated, not by cardioinhibitory M4-receptors. β3-adrenoceptors were found to signal through adenylyl cyclase instead of NO synthase. All these changes were found in the left ventricle only, so heterologous regulation is...
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The Role of Cellular Metabolism in Carcinogenesis. Molecular Pathophysiology of Bladder Cancer Chemoresistance
Kripnerová, Michaela ; Kuncová, Jitka (advisor) ; Nevoral, Jan (referee) ; Chovanec, Miroslav (referee)
Therapeutic resistance of tumours represents an important clinical issue. We can classify the therapeutic tumour resistance in two ways. According to the clinical course, tumours can behave either as primary resistant, i.e. from the very beginning not responsive, or they can display a secondary (also called acquired) resistance, whereby an initial clinical response is lost and the tumour develops into chemo-, radio- or immunoresistant disease. An alternative classification distinguishes cell autonomous resistance mechanisms from resistance that relies on complex interactions within the context of tumour microenvironment. From the research perspective, modelling therapeutic resistance frequently involves experimental treatment of sensitive cancer cells and selection of daughter resistant cell lines. The Ph.D. thesis includes derivation of two unique models of urothelial bladder carcinoma therapeutic resistance. The first model involves newly established urothelial carcinoma cell lines BC44 and BC44DoxoR, which resulted from a prolonged doxorubicin exposure of the mother cell line. The daughter chemoresistant cell line exhibits multidrug resistant phenotype, which extends beyond the selecting drug - doxorubicin - to four additional chemotherapeutic drugs (cisplatin, methotrexate, vinblastine, and...
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Protein profiling, metabolic enzymes and transmembrane signaling in the heart of spontaneously hypertensive SHR-Tg19 rat
Manakov, Dmitry ; Novotný, Jiří (advisor) ; Kuncová, Jitka (referee) ; Kalous, Martin (referee)
Cardiovascular diseases account for the majority of deaths both worldwide and in the Czech Republic. Main factors contributing heart disease development, aside age and sex, are obesity, high blood pressure and high blood cholesterol and triglyceride levels. Spontaneously hypertensive rat (SHR) was developed and used for search of genetic determinants of these traits. This commonly used rat model develops hypertension, dyslipidemia, and insulin resistance naturally which is caused by aberrant Cd36 fatty acid translocase gene. Previous studies have shown that rescue of Cd36 performed in the transgenic SHR-Tg19 strain enhances cardiac beta-adrenergic system, slightly increases heart mass and leads to higher susceptibility to arrhythmias. The present thesis had two main aims: 1) To investigate whether and how a transgenic rescue of Cd36 in SHR affects protein composition, mitochondrial function and activity of selected metabolic enzymes of the heart. 2) To study the expression and distribution of selected components of beta-adrenergic signaling system in lipid raft isolated form membranes using the TX-100 detergent. We set to compare two commonly used proteomic approaches, 2D electrophoresis with MALDI-TOF mass spectrometry and label-free LC-MS. The results did not reveal any overlap between...
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