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Study of leukemic cells' metabolism in association with response to the therapy
Šimčíková, Markéta ; Starková, Júlia (advisor) ; Čuřík, Nikola (referee)
Acute lymphoblastic leukemia (ALL) is the most common malignant dise- ase in children. Despite great advancements in treatment of this disease, around 15-20 % of patients suffer a relapse. One of the possible reasons for relapse is developed resistance to cytostatic drugs. L-asparaginase is an im- portant chemotherapy component for childhood ALL and resistance to this drug often complicates treatment. To date, causes of developing resistance have not been sufficiently described. This thesis is a part of a greater research project focusing on mechanisms of L-asparaginase's activity and reasons for developing resistance to this chemotherapeutic agent. Differential metabolic requirements of cancerous cells have been described as early as 1924 by O. H. Warburg and they have been subject to scientific inquiry since. This study aimed to describe the relationship between basal metabolic determinants of leukemia cells and their sensitivity to L-asparaginase. For this reason, two metabolic pathways, glycolysis and oxidative phosphorylati- on, were studied in detail using a Seahorse Bioanalyzer. Further, expression of specific genes involved in glycolysis was detected. Content of mitochon- drial reticulum in cells, expression of the asparagine synthetase gene, and cell size were also studied. Experiments were...
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Effects of antidepressants and depressive disorders on mitochondrial functions
Hroudová, Jana ; Fišar, Zdeněk (advisor)
Mood disorders are serious diseases. Nevertheless, their pathophysiology is not sufficiently clarified. Biological markers that would facilitate the diagnosis or successful prediction of pharmacotherapy are still being sought. The aim of the study was to find out whether mitochondrial functions are affected by antidepressants, mood stabilizers and depression. Our research is based on recent hypotheses of mood disorders, the advanced monoamine hypothesis, the neurotrophic hypothesis, and the mitochondrial dysfunction hypothesis. We assume that impaired function of mitochondria leads to neuronal damage and can be related to the origin of mood disorders. Effects of antidepressants and mood stabilizers on mitochondrial functions can be related to their therapeutic or side effects. In vitro effects of pharmacologically different antidepressants and mood stabilizers on the activities of mitochondrial enzymes were measured in mitochondria isolated from pig brains (in vitro model). Activity of monoamine oxidase (MAO) isoforms was determined radiochemically, activities of other mitochondrial enzymes were measured spectrophotometrically. Overall activity of the system of oxidative phosphorylation was measured electrochemically using high- resolution respirometry. Methods were modified to measure the same...
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Mitochondrial ATP synthase deficiencies of a nuclear genetic origin
Karbanová, Vendula ; Houštěk, Josef (advisor) ; Kalous, Martin (referee) ; Rossmeisl, Martin (referee)
ATP synthase represents the key enzyme of cellular energy provision and ATP synthase disorders belong to the most deleterious mitochondrial diseases affecting pediatric population. The aim of this thesis was to identify nuclear genetic defects and describe the pathogenic mechanism of altered biosynthesis of ATP synthase that leads to isolated deficiency of this enzyme manifesting as an early onset mitochondrial encephalo-cardiomyopathy. Studies in the group of 25 patients enabled identification of two new disease-causing nuclear genes responsible for ATP synthase deficiency. The first affected gene was TMEM70 that encodes an unknown mitochondrial protein. This protein was identified as a novel assembly factor of ATP synthase, first one specific for higher eukaryotes. TMEM70 protein of 21 kDa is located in mitochondrial inner membrane and it is absent in patient tissues. TMEM70 mutation was found in 23 patients and turned to be the most frequent cause of ATP synthase deficiency. Cell culture studies also revealed that enzyme defect leads to compensatory-adaptive upregulation of respiratory chain complexes III and IV due to posttranscriptional events. The second affected gene was ATP5E that encodes small structural epsilon subunit of ATP synthase. Replacement of conserved Tyr12 with Cys caused...
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Effects of antidepressants and depressive disorders on mitochondrial functions
Hroudová, Jana ; Fišar, Zdeněk (advisor) ; Martásek, Pavel (referee) ; Kuča, Kamil (referee)
Mood disorders are serious diseases. Nevertheless, their pathophysiology is not sufficiently clarified. Biological markers that would facilitate the diagnosis or successful prediction of pharmacotherapy are still being sought. The aim of the study was to find out whether mitochondrial functions are affected by antidepressants, mood stabilizers and depression. Our research is based on recent hypotheses of mood disorders, the advanced monoamine hypothesis, the neurotrophic hypothesis, and the mitochondrial dysfunction hypothesis. We assume that impaired function of mitochondria leads to neuronal damage and can be related to the origin of mood disorders. Effects of antidepressants and mood stabilizers on mitochondrial functions can be related to their therapeutic or side effects. In vitro effects of pharmacologically different antidepressants and mood stabilizers on the activities of mitochondrial enzymes were measured in mitochondria isolated from pig brains (in vitro model). Activity of monoamine oxidase (MAO) isoforms was determined radiochemically, activities of other mitochondrial enzymes were measured spectrophotometrically. Overall activity of the system of oxidative phosphorylation was measured electrochemically using high- resolution respirometry. Methods were modified to measure the same...
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