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Calcium signalling in glial cells in progress of Alzheimer disease
Waloschková, Eliška ; Anděrová, Miroslava (advisor) ; Maršáková, Lenka (referee)
Alzheimer's disease (AD) is a neurodegenerative disorder affecting the entire central nervous system including glial cells. The mechanisms of this disease are not yet entirely clear, although recent studies suggest that among the known hallmarks of AD, such as accumulation of amyloid β and hyperphosphorylated tau, dysregulation of intracellular calcium homeostasis is proposed to be a significant feature both in neurons and glial cells, namely astrocytes and microglia. Glial cells play an important role both in healthy brain and during AD progression. Their major functions, such as supporting neurons or maintaining synapses, are impaired during this disease. Recent findings suggest that aberrant glial calcium signaling activated during AD, could possibly promote the malfunction of these cells and increase their inflammatory response, thus affecting neurons and causing brain damage. It is likely, that the ongoing inflammation and the impaired calcium signaling affect one another, consequently enhancing the progression of AD.
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Molecular mechanism of mechanoreception in plants
Jelínková, Barbora ; Martinek, Jan (advisor) ; Fendrych, Matyáš (referee)
Plant, as sedentary organism, does not have many possibilities to physically escape it's unpleasant surroundings, instead it adapts oneself. One of many plant senses that are crucial for tracking environment changes is mechanoreception. Plant senses and differentiates between many mechanical cues, some of them affecting plant immunity and morphogenesis. The whole plant cell reacts to mechanical cues and many cellular structures are involved in mechanoreception. Any change in cell wall - a borderline between the cell and it's surroundings - is transduced to plasma membrane, then to the cytoskeleton and potentially to other structures. Concept of this cell wall-plasma membrane-cytoskeleton continuum and it's use as an instrument to illuminate molecular mechanisms of mechanoreception in plants are the key topics of my thesis.
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Calcium signalling in astrocytes under physiological and pathological conditions
Svatoňová, Petra ; Anděrová, Miroslava (advisor) ; Kolář, David (referee)
Calcium signalling in astrocytes represents an important component, which enables proper neuronal functioning under physiological conditions. Alterations in Ca2+ signalling, accompanied by an increase in intracellular calcium levels is a hallmark for numerous pathological states of central nervous system, such as traumatic and ischemic brain/spinal cord injuries, epilepsy as well as neurodegenerative diseases, such as Alzheimer's disease and psychiatric disorders, such as schizophrenia. The research analyzing the molecular components of astrocytic Ca2+ signalling can help us understand the control mechanisms used in calcium signalling and thus be greatly beneficial for further therapeutic research. Powered by TCPDF (www.tcpdf.org)
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Ca2+ signalling in magnocellular neurones of the rat supraoptic nucleus.
Kortus, Štěpán ; Zápotocký, Martin (advisor) ; Šuta, Daniel (referee) ; Hromádka, Tomáš (referee)
The magnocellular neurosecretory cells (MNCs) of the hypothalamus project axons from the supraoptic nucleus to the posterior pituitary gland, where they secrete either oxytocin or vasopressin into the circulation. Oxytocin is important for delivery at birth and is essential for milk ejection during suckling. Vasopressin primarily promotes water reabsorption in the kidney to maintain body fluid balance. The profile of oxytocin and vasopressin secretion is principally determined by the pattern of action potentials initiated at the cell bodies in the hypothalamus. MNCs principally secrete hormones from terminals in the pituitary, but the secretion also occurs from their dendrites in the supraoptic nucleus, where they diffuse and affect the neighbouring cells. Mechanisms controlling the oxytocin and vasopressin secretion from MNCs have been extensively studied over the last decades and it is assumed that the relationship between Ca2+ signalling, secretion from dendrites, and the firing patterns is essential in understanding the magnocellular neurosecretory system. In this project, we combine mathematical analysis and experimental measurements of Ca2+ activity of MNCs of transgenic rats expressing an arginine vasopressin-enhanced green fluorescent protein (AVP-eGFP) or oxytocin-monomeric red fluorescent...
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Circadian system in astrocytes
Ľalíková, Kristýna ; Bendová, Zdeňka (advisor) ; Honc, Ondřej (referee)
The circadian system affects almost all cells in the mammalian body. These cells include astrocytes, which together with microglia and oligodendrocytes represent the main types of glial cells found in the brain. The first chapter of this thesis presents a summary of circadian system characteristics and focuses mainly on the molecular mechanism underlying its functioning. The second chapter is devoted to astrocytes, astrocyte calcium signaling, and the process of gliotransmission. The third and last chapter connects both topics and discusses the circadian system in astrocytes. It presents evidence of astrocytic circadian oscillations existence and physiological consequences of its action. Great attention is paid to circadian rhythms in gliotransmission, with a focus on gliotransmitters ATP and glutamate. As the most impressive output of the circadian system of astrocytes is presented the participation in maintaining the rhythmic activity of the main circadian oscillator located in the suprachiasmatic nucleus of the hypothalamus. Key words: circadian system, clock genes, astrocytes, gliotransmission, calcium signaling, glutamate, ATP
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Ca2+ signalling in magnocellular neurones of the rat supraoptic nucleus.
Kortus, Štěpán ; Zápotocký, Martin (advisor) ; Šuta, Daniel (referee) ; Hromádka, Tomáš (referee)
The magnocellular neurosecretory cells (MNCs) of the hypothalamus project axons from the supraoptic nucleus to the posterior pituitary gland, where they secrete either oxytocin or vasopressin into the circulation. Oxytocin is important for delivery at birth and is essential for milk ejection during suckling. Vasopressin primarily promotes water reabsorption in the kidney to maintain body fluid balance. The profile of oxytocin and vasopressin secretion is principally determined by the pattern of action potentials initiated at the cell bodies in the hypothalamus. MNCs principally secrete hormones from terminals in the pituitary, but the secretion also occurs from their dendrites in the supraoptic nucleus, where they diffuse and affect the neighbouring cells. Mechanisms controlling the oxytocin and vasopressin secretion from MNCs have been extensively studied over the last decades and it is assumed that the relationship between Ca2+ signalling, secretion from dendrites, and the firing patterns is essential in understanding the magnocellular neurosecretory system. In this project, we combine mathematical analysis and experimental measurements of Ca2+ activity of MNCs of transgenic rats expressing an arginine vasopressin-enhanced green fluorescent protein (AVP-eGFP) or oxytocin-monomeric red fluorescent...
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Molecular mechanism of mechanoreception in plants
Jelínková, Barbora ; Martinek, Jan (advisor) ; Fendrych, Matyáš (referee)
Plant, as sedentary organism, does not have many possibilities to physically escape it's unpleasant surroundings, instead it adapts oneself. One of many plant senses that are crucial for tracking environment changes is mechanoreception. Plant senses and differentiates between many mechanical cues, some of them affecting plant immunity and morphogenesis. The whole plant cell reacts to mechanical cues and many cellular structures are involved in mechanoreception. Any change in cell wall - a borderline between the cell and it's surroundings - is transduced to plasma membrane, then to the cytoskeleton and potentially to other structures. Concept of this cell wall-plasma membrane-cytoskeleton continuum and it's use as an instrument to illuminate molecular mechanisms of mechanoreception in plants are the key topics of my thesis.
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Calcium signalling in astrocytes under physiological and pathological conditions
Svatoňová, Petra ; Anděrová, Miroslava (advisor) ; Kolář, David (referee)
Calcium signalling in astrocytes represents an important component, which enables proper neuronal functioning under physiological conditions. Alterations in Ca2+ signalling, accompanied by an increase in intracellular calcium levels is a hallmark for numerous pathological states of central nervous system, such as traumatic and ischemic brain/spinal cord injuries, epilepsy as well as neurodegenerative diseases, such as Alzheimer's disease and psychiatric disorders, such as schizophrenia. The research analyzing the molecular components of astrocytic Ca2+ signalling can help us understand the control mechanisms used in calcium signalling and thus be greatly beneficial for further therapeutic research. Powered by TCPDF (www.tcpdf.org)
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Calcium signalling in glial cells in progress of Alzheimer disease
Waloschková, Eliška ; Anděrová, Miroslava (advisor) ; Maršáková, Lenka (referee)
Alzheimer's disease (AD) is a neurodegenerative disorder affecting the entire central nervous system including glial cells. The mechanisms of this disease are not yet entirely clear, although recent studies suggest that among the known hallmarks of AD, such as accumulation of amyloid β and hyperphosphorylated tau, dysregulation of intracellular calcium homeostasis is proposed to be a significant feature both in neurons and glial cells, namely astrocytes and microglia. Glial cells play an important role both in healthy brain and during AD progression. Their major functions, such as supporting neurons or maintaining synapses, are impaired during this disease. Recent findings suggest that aberrant glial calcium signaling activated during AD, could possibly promote the malfunction of these cells and increase their inflammatory response, thus affecting neurons and causing brain damage. It is likely, that the ongoing inflammation and the impaired calcium signaling affect one another, consequently enhancing the progression of AD.
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Fluorescence studies of bacterial membrane proteins and cell signalling.
Fišer, Radovan ; Konopásek, Ivo (advisor) ; Hof, Martin (referee) ; Forstová, Jitka (referee)
(English) This work is based on five publications studying mostly adenylate cyclase toxin (CyaA) from Bordetella pertussis and its interaction with biological membranes. CyaA permeabilizes cell membranes by forming small cationselective pores and subverts cellular signaling by delivering an adenylate cyclase (AC) enzyme that converts ATP to cAMP into host cells. First study clarifies the membrane disruption mechanisms of CyaA and another bacterial RTX toxin; αhemolysin (HlyA) from Escherichia coli. For this purpose, we employed a fluorescence requenching method using liposomes as target membranes. We showed that both toxins induced a graded leakage of liposome content with different ion selectivities (Fišer a Konopásek 2009). Both AC delivery and pore formation were previously shown to involve a predicted amphipathic αhelix(502522). In the second publication we investigated another predicted transmembrane αhelix(565591) that comprises a Glu(570) and Glu(581) pair. We examined the roles of these glutamates in the activity of CyaA, mostly on planar lipid membranes end erythrocytes. Negative charge at position 570, but not at position 581, was found to be essential for cation selectivity of the pore, suggesting a role of Glu(570) in...
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