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The effect of the gut microbiota in eating disorders
Hlaváčková, Helena ; Roubalová, Radka (advisor) ; Černý, Viktor (referee)
The essential effect of microbiota on human health has been well known for a long time. Commensal microorganisms colonize virtually the entire surface of the human body, but the greatest amount of them can be found in the gut. The gut microbiota plays a crucial role in the digestion of certain food components, synthesis of various substances, or the immune system responses. In the last decade, attention has also been drawn to the mechanisms by which gut microorganisms can influence the human behaviour. One group of diseases, where this phenomenon is being explored, are eating disorders. This is a group of psychiatric disorders characterized by unhealthy eating behaviors. The aim of this thesis is to summarize current knowledge about the mechanisms by which gut microorganisms can interfere with host signaling and regulatory pathways and how these changes relate to the development and course of eating disorders. And from the opposite view, how the patients' behaviour impacts the composition and functioning of the gut microbiota.
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Immunomodulatory properties of microbial components
Pavličová, Anna ; Kverka, Miloslav (advisor) ; Prokešová, Ludmila (referee)
The human body is inhabited by a complex composition of microorganisms. Particularly significant is the intestinal microbiota due to its profound effect on the development and function of the immune system. The ability of the host to defend against pathogens is kept by two important, interrelated components - the mucosal barrier and immune system. The barrier is composed of several layers (gut microbiota, mucus, epithelium, and immune cells) joined into one functional unit. Through its diverse array of structural components and metabolites, the gut microbiota interacts with the epithelium and mucosal immune system, confers to its induction, and modulates immune responses. Disruption of this interplay can contribute to pathogenesis of several diseases.
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Preparation of food supplement containing probiotic bacteria and components with anti-inflammatory effect
Horňáková, Nikola ; Němcová, Andrea (referee) ; Skoumalová, Petra (advisor)
The presented thesis discusses the issues of chronic inflammatory diseases of the digestive system and suggests the possibility of the alternative natural remedies improving the health conditions or prolonging the remission phase of IBD. The main goal is to design a probiotic supplement enriched by natural anti-inflammatory agents. Phytochemicals, concretely phenolic compounds, flavonoids, and carotenoids suppress harmful inflammatory processes by direct targeting the function of the immune cells or by inhibiting damaging oxidative stress in general. Therefore, there were several plants potentially rich for these biologically active substances selected. Concretely, blueberry (Vaccinium myrtillus), lingonberry (Vaccinium vitis-idaea), turmeric (Curcuma longa), peppermint (Mentha piperita), chamomile (Matricaria recutita), cinnamon (Cinnamomum zeylanicum), ginger (Zingiber officinale) and flax (Linum usitatissimum). The suitable parts of these plants were extracted by using a total of three different solvents – water, ethanol, and hexane for obtaining lipidic extracts. The concentration of total polyphenols, total flavonoids, total carotenoids, and the ascertainment of specific polyphenols was determined in the prepared extracts. These characteristics were enhanced by the measurement of antioxidant activity of the aqueous and ethanolic extracts. The interaction of individual samples with probiotic cultures (Bifidobacterium breve, Lactobacillus acidophilus) and the ability of extracts to influence the viability of probiotics in the model digestion process has been examined. The most interesting samples (aqueous extracts of blueberries, mint, chamomile, and cinnamon) were selected for further experiments. The possible cytotoxicity towards human intestinal epithelial cells was tested in vitro by the MTT tests utilizing the CaCo-2 cell line. Extracts showing the highest levels of beneficial phytochemicals and antioxidant activity, supporting the growth of probiotic cultures, and showing minimal cytotoxic effects on human intestinal cells were then co-encapsulated with probiotics into alginate particles of a diameter of 1 mm. Water extracts of mint, chamomile, and cinnamon have been chosen. The encapsulation efficiency of successfully entrapped probiotics and phenolic compounds was determined in prepared particles. Furthermore, the particles were studied during the process of model digestion, when the release of the desired substances in the various parts of the digestive system was observed and assessed whether the components would reach the crucial point of action – the colon. For the use of the proposed probiotic mixture as a dietary supplement, a recommended dose of 1 g has been determined. Lastly, possible adjustments such as lyophilization or sheathing by an extra protective polymerous layer, e.g. chitosan, were suggested to prolong the shelf life of the particles and volatile substances stability.
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Opioid-induced microbial dysbiosis
Popjak, Šimon ; Drastichová, Zdeňka (advisor) ; Stehlíková, Zuzana (referee)
The aim of this bachelor thesis is to describe the consequences of opioids in relation to the gut microbiome. Chronic opioid use induces microbial dysbiosis in the gut, where both functional and structural changes in the composition of the microbiome occur. This disrupts gut homeostasis and leads to diseases. The diversity of microbial organisms decreases and the expression of neurotransmitters changes. Opioids interfere with the microbiomeň-gut-brain axis, which normally functions in symbiosis. They alter the composition of the gut microbiota, affect the function and structure of the gut epithelium and the expression of neurotransmitters in the nervous system. This thesis focuses primarily on the action of morphine, the action of which has been desribed the most. Keywords: opioids, microbiome, dysbiosis, microbiome-gut-brain axis, gut homeostasis
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Influence of experimental intestinal dysbiosis on behavioral, neuroendocrine and immune properties of mice and the possibility of modifying it by administration of probiotic strain Escherichia coli O83:K24:H31
Avramová, Pavla ; Černý, Viktor (advisor) ; Roubalová, Radka (referee)
The gut microbiota is a key factor influencing the function of many organs in the human body, including the nervous, immune, and endocrine systems. This dynamic ecosystem can be modulated by diet, age, environment, even medication. The balanced composition of the microbiota is crucial for individual health, and its disruption leads to dysbiosis. The connection between the gut and the central nervous system is mediated by the microbiota-gut- brain axis. This axis consists of several pathways interconnected to mutually regulate their functions. Among the major components of the axis are the neural pathway, led by the vagus nerve, the immune pathway, and the endocrine pathway, including the HPA axis. Recent studies suggest that probiotic bacteria have the ability to partially rectify dysbiosis and alleviate its consequences for the organism. This thesis focuses on researching the impact of gastrointestinal tract microbiota on the behaviour, immunity, and neuroendocrine aspects of mice. It delves into experimentally inducing dysbiosis using antibiotics and subsequently addressing it with the probiotic bacterium Escherichia coli O83:K24:H31. The aim is to determine whether these probiotics can mitigate the adverse effects of dysbiosis on the immune and neuroendocrine systems, as well as behavioural...
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Probiotics, prebiotics, synbiotics and postbiotics in breast milk and formulas.
ŠEBÍKOVÁ, Lucie
Intestinal microbiotics make up about 80 % of our immunity. The biggest colonization by these microorganisms happens in the first 1000 days in the life of a child, which is why it is important to maintain a balanced diet, to properly support growth and diversity of an intestinal flora. In the theoretic part of my thesis I will look closely on composition of breast milk and on other kinds of substitution of dairy nutrition. You will learn that many factors affect the composition of intestinal microbiotics. For if it comes to dysmicrobia, for example as a result of long-term use of antibiotics, it could lead to development of metabolic, immunologic and psychic issues. The goal of my bachelor thesis was to learn the contents of probiotics, prebiotics, postbiotics and synbiotics in breast milk, and in the formulas in the 1st, 6th, 12th and 18th month. My sources were professional literature and the websites of chosen dairy nutrition. For learning the exact intake of the observed substances I evaluated menus from 10 respondents. Breast milk is the most natural form of nutrition, which is why it is used as a template for making the substitution of dairy nutrition. The closest to breast milk in contents of synbiotics are brands Hipp BIO combiotik and BEBA COMFORT HM-O. Nutrilon advance has the most similar count of prebiotics, which was confirmed by observing the specific intake from menus. Nutrilon and Hami are only brands containing postbiotics thanks to the process of directed fermentation Lactofidus. This data should help in deciding what substitution of dairy nutrition to choose, if a child cannot be breastfed. But since this thesis does not evaluate the complete contents of the formulas, but rather the contains of the observed substances, we cannot presume the brands with the best results are the best option of nutrition. The choice of nutrition should be discussed with a pediatrician or a nutritionist.
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Effect of intestinal microflora on the activity of higher brain centers
Arnold, Tomáš ; Hock, Miroslav (advisor) ; Melkes, Barbora (referee)
Abstract Intestinal microflora consists of large bacterial community that resides in the intestines, especially the colon, and lives in symbiosis with the host. It consists mainly representatives of the four bacterial strains (Actinobacteria, Bacteroidetes, Firmicutes and Proteobacteria). It has already been shown that the proportional representation of the bacterial strains in time does not change much, but the research of the last decade have shown irrefutable effect between the change of diet and composition of the intestinal microflora. In addition, there is evidence of changes in the representation of bacterial strains in the course of development of certain intestinal pathologies such as inflammatory bowel disease. More and more are starting to emerge papers describing the influence of altered intestinal microflora respectively its representatives, on the activity and function of the CNS. This interaction of the digestive system and CNS seems to be bidirectional and mediated by several different pathways. Finally, it shows that dysbiosis of the intestinal microflora promotes anxiety and depression that can lead to the urge to prematurely terminate life. The aim of this work is to provide a comprehensive view of this relatively young, but also very interesting...
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Role of bacteria and mucosal immune system and their interaction in the pathogenesis of inflammatory bowel disease
Du, Zhengyu ; Hudcovic, Tomáš (advisor) ; Prokešová, Ludmila (referee) ; Kamanová, Jana (referee)
Although the etiology and pathogenesis of inflammatory bowel disease (IBD) is not fully understood, it is generally accepted that the inflammation results from aberrant immune responses to antigens of gut microbiota in genetically susceptible individuals (Sartor et al., 2006). Alteration in intestinal microbiota has been found in IBD patients with increased abundance of certain bacteria and decreased abundance of others. Due to the complexity of the disease, multifaceted interactions between genetic factors, host immune response, gut microbiota and environment factors need to be taken into account. In this thesis, the pathogenesis of IBD was first reviewed in respect with the four factors mentioned above. Then we concentrated on the interaction between IBD-associated bacteria and mucosal immune system. We investigated the ability of mucosal-associated bacteria (MAB) from IBD patients to induce spontaneous colitis in germ-free (GF) mice and the impact of those bacteria on the development of dextran sulfate sodium (DSS)-colitis. Together with the analysis of the composition of gut microbiota of MAB colonized mice, we demonstrated the potential deleterious microbes were able to increase the susceptibility to DSS-colitis once they found a suitable niche. We revealed the mechanism of an E.coli strain...
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