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Impact of circadian system disruption on development of gastrointestinal disorders
Kubištová, Aneta ; Sumová, Alena (advisor) ; Červená, Kateřina (referee)
The ability to sense 24-hour cycles in external environment and to adapt to them is present in a great array of species living on the Earth. Mammals possess internal time-keeping system which is composed of circadian clocks located in the suprachiasmatic nuclei (SCN) of the hypotalamus and peripheral clocks in various tissues and organs of the body. These clocks are adapting to the changes of external environment, such as light and dark cycles or feeding cycles. Peripheral clocks in the organs of the digestive system are synchronized with the signals derived from the central clock in the SCN and also with signals from food intake. Discordance between these signals may result in development of various diseases of the gastrointestinal tract (GIT) related to insufficient digestion or even in higher risk of developing a cancer. This bachelor thesis is generally aimed at circadian rhythms in the body, with the focus on rhythms in the GIT. It will deal with the importance of the circadian rhythms for correct GIT functions. Furthermore, the thesis is focused on connection between the desynchonization of the circadian clock and GIT disease development, namely of obesity and cancer.
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Gut microbiota effect on neuropsychiatric diseases
Pospíšil, Vít ; Kostovčíková, Klára (advisor) ; Červená, Kateřina (referee)
The intestinal microbiome is formed by trillions of microorganisms that accompany us throughout our lives. Commensal gut microorganisms, as a complex system, interfere with diet processing and subsequent spectrum of released metabolites, which are involved in communication with other systems of the human body. Recently, a link between intestinal microbiota dysbiosis and activation of the immune response has begun to emerge. This pathophysiological condition is associated with the loosening of the tight junctions of the gut epithelial barrier, which could together with prolonged immune inflammation lead to what is known as irritable bowel syndrome. This disease is not only related to symptoms associated with bowel discomfort, but also to effects on afferent nerve endings. This connection has been called as the gut-brain axis and became the link between the gut microbiota and psychiatric diseases. This work is summing up the actual knowledge on this topic and offers a comprehensive overview of the subject from both an immunological and a microbiological point of view. Key words: gut-brain axis, depression, anxiety, antibiotics, antidepressants, probiotics, IBS
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The role of cannabinoid signaling in neuroprotection
Mádrová, Eliška ; Novotný, Jiří (advisor) ; Červená, Kateřina (referee)
The name of the endocannabinoid system comes from Cannabis sativa which contains Δ9 -THC that causes psychotropic effects through cannabinoid receptors. It was discovered that Δ9 -THC is not the only ligand of the cannabinoid system but there also naturally exist endogenous cannabinoids in the human body. The main endogenous cannabinoids are anandamide and 2-arachidonoylglycerol which act on various receptors, primarily cannabinoid receptors CB1 and CB2 that fall into a group of G-protein coupled receptors, but they may also affect vanilloid receptor TRPV1 or nuclear peroxisome proliferator-activated receptor PPARγ. By studying the cannabinoid system, it was discovered that cannabinoids can modulate some of the cellular processes such as cell growth, proliferation and differentiation of cells, apoptosis and intracellular concentration of Ca2+ . Recently they have been primarily studied for their usefulness in the treatment of neurodegenerative diseases, for example, Alzheimer's disease, multiple sclerosis or epilepsy because it has been shown that they support the survival of neurons during excitotoxicity and they modulate the release of cytokines responsible for the regulation of the immune system and inflammatory response. Key words: cannabinoid receptors, G proteins, neuroprotection, Δ9 -THC,...
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Chronotypes and Social Jet Lag Related to Obesity
Halászová, Andrea ; Fárková, Eva (advisor) ; Červená, Kateřina (referee)
In nature we can observe plenty of actions which show some kind of regularity as they repeat with a certain period. The circadian rhythm with its period of approximately one day belongs among these. The circadian rhythm is synchronized mainly by light, but there are also many other internal and especially external synchronizers such as the society we live in. In an organism many processes show circadian rhythmicity, but everyone has the rhythm adjusted individualy, thus called chronotype. It's indeed very important to note that living in harmony with the chronotype is essential. Social jet lag is the term for a long-term disbalance and circadian desynchrony as a consequence of the need to adjust this individual circadian preference to the regime set by the society we live in. Many of recent studies support the findings, that social jet lag might have an impact on health and could participate in development of some of the lifestyle diseases such as obesity. Therefore it should be found beneficial to apply those finding in a clinic practise not only in order to help with an efficient treatment of obesity and its consequences but also in preventing it.
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Role of interneurons and neural circuit dysfunctions in Alzheimer's disease
Rakovets, Yuliia ; Stuchlík, Aleš (advisor) ; Červená, Kateřina (referee)
Alzheimer's disease is one of the most common neurodegenerative disorder that results in altered network activity, in particular cognitive decline. Majority people with AD experience memory impairment, poor judgment, disorientation and learning difficulties. Several hypotheses try to explain the cause of the disease, but it's poorly understood. Due to the fact that changes in brain structure arise years before clinical symptoms emerge, the available therapeutic treatments can only reduce the impact of neurodegeneration, but not to reverse. Interneurons, as a part of neural circuits, play an important role in the formation of cognitive abilities. Most of interneurons in CNS are inhibitory and they effectively control the network synchrony. Network hypersynchrony is an increased synchronization of neural activity and it's linked to AD pathology. Dysfunction of interneurons is resulted in altered network activity in patients with AD. Keywords: AD, brain, rat, interneurons, hypersynchrony.
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Impact of circadian system disruption on development of gastrointestinal disorders
Kubištová, Aneta ; Sumová, Alena (advisor) ; Červená, Kateřina (referee)
The ability to sense 24-hour cycles in external environment and to adapt to them is present in a great array of species living on the Earth. Mammals possess internal time-keeping system which is composed of circadian clocks located in the suprachiasmatic nuclei (SCN) of the hypotalamus and peripheral clocks in various tissues and organs of the body. These clocks are adapting to the changes of external environment, such as light and dark cycles or feeding cycles. Peripheral clocks in the organs of the digestive system are synchronized with the signals derived from the central clock in the SCN and also with signals from food intake. Discordance between these signals may result in development of various diseases of the gastrointestinal tract (GIT) related to insufficient digestion or even in higher risk of developing a cancer. This bachelor thesis is generally aimed at circadian rhythms in the body, with the focus on rhythms in the GIT. It will deal with the importance of the circadian rhythms for correct GIT functions. Furthermore, the thesis is focused on connection between the desynchonization of the circadian clock and GIT disease development, namely of obesity and cancer.
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Molecular mechanisms of circadian clock entrainment by daily regime in food intake
Kapoun, Jiří ; Sumová, Alena (advisor) ; Červená, Kateřina (referee)
Circadian clocks form an endogenous time-keeping system present in most organisms, synchronizing physiological and behavioural processes with perodically changing environmental conditions. The system comprises of the master clock in the suprachiasmatic nuclei of the hypothalamus and numerous subsidiary clocks in peripheral tissues. Its molecular design is constituted by the clock genes, which are rhythmically expressed, form a series of transcriptional/translational feedback loops and influence the expression of various other genes involved in metabolic pathways. The peripheral clocks are dependent on the master clock, although they can be entrained with external cues like food intake timing and diet composition. This desynchronization leads to the distruption of clock gene oscillation, which can potentially have serious impact on metabolic processes and increase the risk of metabolic disorders. The aim of this thesis is to summarize current knowledge on the relationship of molecular chronobiology and nutrition with a focus on the molecular mechanisms through which can food, especially its intake timing and composition, influence the crosstalk between clock gene expression and cellular metabolism. The thesis also emphasises the potential effect of circadian clock disruption on the risk of metabolic...
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Comparison of episodic memory research approaches in human, from the viewpoint of cognitive psychology and neuroscience.
Kočí, Markéta ; Vlček, Kamil (advisor) ; Červená, Kateřina (referee)
Episodic memory allows a person to recall events of one's personal past. During the retrieval, memory is re-experienced as a vivid imaginary experience, accompanied by a rich temporo-spatial context and autonoetic consciousness - awareness of the self. Further episodic memory characteristics are captured in its several models. Some of them focus on the encoding, consolidation and retrieval processes, other on the spatial context, time duration of events, autobiographical context or characteristic feelings during retrieval. The models differ in some aspects and converge in other aspects, and given together they provide general view on episodic memory approaches.
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