|
|
Host-microbe interactions and its consequences for intestinal inflammation and carcinogenesis
Kejzlarová, Leona ; Kverka, Miloslav (advisor) ; Smrž, Daniel (referee)
A number of physiological and pathological processes, including the transition from chronic inflammation to cancer, are affected by commensal microbes. However, abundance of microbes and ability to produce active metabolites in the intestine depend on environmental factors, particularly diet. Microbes can influence this process in two ways, by producing genotoxic substances that directly damage the epithelium or by stimulating the inflammatory response. The aim of my thesis was to study the interaction among gut microbiota, diet and the immune system with the subsequent influence on the development of colorectal cancer (CRC) in an experimental mouse model. Animals were fed synthetic diets containing either normal amounts of animal protein (17%; KD) or elevated amounts of animal protein (51%; HPD) throughout the experiments. Two weeks after the diets were introduced, intestinal tumors were induced by administering azoxymethane (AOM) and inducing acute inflammation with 2% sodium dextran sulfate one week after AOM injection. At the end of the experiment I evaluated the number of tumors in the colon and the status of the immune response in the intestine, mesenteric lymph nodes and spleen. To study the effect of macrophages, a similar experiment was performed in animals with depleted macrophages using...
|
|
|
Changes of gut microbiome in patients with inflammatory bowel diseases
Schierová, Dagmar ; Jirásková Zákostelská, Zuzana (advisor) ; Hrdý, Jiří (referee) ; Kohout, Pavel (referee)
(EN) Microbes have coevolved with humans forming symbiotic communities that constantly challenge the immune system and, when imbalanced, could lead to diseases like inflammatory bowel disease (IBD). Patients with IBD suffer from microbial dysbiosis and chronic inflammation which could be potentiated by immune system reaction to the commensal microbiota. In the research presented here, firstly I have focused on the description of the gut and skin microbiome from patients with IBD and secondly, I investigated the process of antimicrobial defense. Patients with IBD on two different biological therapies targeting TNFα, IL-12 and IL-23 cytokines were tracked for changes in their gut and skin microbiome features. Although, neither differences in gut microbial diversity nor composition were linked with the progression of the therapies, an increased similarity to the healthy control group at week 38 of anti-TNFα therapy was found. This shift in microbiome could be considered beneficial and could be attributed to the inflammation reducing effect of the therapy. While analyzing the microbiome features, various patient characteristics were taken into account and the sources microbiome of variability were uncovered, out of which the interindividual variability stood out the most. Regarding the skin microbiome,...
|
|
|
Kvantitativní zastoupení bakterií rodu Lactobacillus v lidském zažívacím traktu v závislosti na změně stravovacích návyků
Kolísková, Kateřina
This diploma thesis deals with the issue of quantitative representation of the bacterial family in the human digestion system depending on changes in eating habits. The start of literary digest addresses general characteristics of digestion microbiome and its bacterial represen-tation. The most comprehensive part belongs to individual factors, who influenced overall number of bacterial species inhabiting the digestion microbiome. The last chapters of the theoretical part belong to cultivative and molecular biological methods, which are used in examination of the human digestion tract. Experimental part focuses on differences in the number of individual bacteria in the samples of human excrements, whose presence was determined by cultivative methods. Isolation of bacterial DNA was performed, which was subsequently confirmed by polymerase chain reaction. In resulting values, we observed small changes (p < 0,05) in bacterial species L. acidophilus a L. rhamnosus at the end of the second period. All bacterial families, except Bacteroides, had downward tendency (p > 0,05). Based on acquired data from food records, we observed changes in consumption of basic macronutrients (protein, fat, carbohydrates) and fiber. Only in carbohydrates and sim-ple sugars, we observed statistically provable differences (p > 0,05). Final analysis proved that changes in eating habits did not influence the total number of bacterial species inhabiting digestion microbiome.
|
|
|
Current knowledge about the influence of the intestinal microbiome on the development, course and consequences of lactose intolerance
Černá, Pavlína ; Tomešová, Jitka (advisor) ; Kohout, Pavel (referee)
The bachelor thesis investigates the current knowledge about the influence of the gut microbiome on the development and severity of lactose intolerance, as well as whether and how it can be changed to influence the course of existing lactose intolerance and its immediate and long- term consequences. In the first part of this bachelor thesis I discuss lactose itself and its metabolism, which shows its direct link to the gastrointestinal tract. Lactose intolerance (LI) is also described, how it is diagnosed, what it manifests itself as, and what its degrees are. The next chapter discusses the relationship between LI, the gut, and the gut microbiome. First, I focus here on the possible adaptability of the gut, which is mainly determined by the presence of the microbiome. There is also a link between LI and other gastrointestinal disorders in which gut bacteria play a role. The microbiome is a very dynamic population of different types of bacteria, fungi and viruses that can influence the course of lactose intolerance. This can be exploated in the subsequent therapy of LI with probiotics, which are included in part three. The most commonly used probiotic bacteria are representatives of the genus Bifidobacterium and Lactobacillus. However, probiotics are not the only option for using the gut microbiome...
|
|
|
Circadian regulation of digestive system function and its disturbances due to external factors
Běloušková, Klára ; Sumová, Alena (advisor) ; Balounová, Kateřina (referee)
Circadian clocks regulate the behavior of cells in living organisms in 24hour periods. They react to environmental influences and, by synchronizing with them, ensure optimal cell function and the overall health of the organism. Biological clocks in the gastrointestinal tract and their functions can be influenced by several factors, including the timing of food intake or the influence of the microbiome. The correct timing of food intake can be essential in maintaining the functional physiology of the organism as well as the appropriate composition of the gut microbiome. Disruption of the synchronization between these factors and the biological clock in the gastrointestinal tract leads to disharmony of the organism, its improper function and the development of disease. The timing of food intake and the cultivation of an appropriate microbiome is critical to maintaining optimal health and should not be neglected by the public.
|
|
|
Processing and analysis of the human gut microbiome from 16S rDNA sequencing data
Zbudilová, Michaela ; Jurečková, Kateřina (referee) ; Nykrýnová, Markéta (advisor)
This bachelor´s thesis deals with the analysis of the human intestinal microbiome from 16S rRNA data. In the first part, the intestinal microbiome is theoretically described, and then the methods of its processing and evaluation using analysis of taxonomic categories and sample diversity are mentioned. The second part focuses on the data processed in the thesis and the format in which those data are provided. In the third part, the proposed algorithm used to process the data is described, and the results obtained by running this algorithm are evaluated. In the fourth part of the thesis, the samples from the University Hospital Brno are processed using the proposed algorithm. The last part of the thesis focuses on the script, which is used to generate the reports which can be used for diagnostic purposes in the University Hospital Brno.
|
|
|
Gut microbiome and autoimmune mechanisms in patients with type 1 narcolepsy
Ježková, Janet ; Roubalová, Radka (advisor) ; Hrdý, Jiří (referee)
Narcolepsy Type 1 (NT1) is a chronic neurological disease characterized by the presence of cataplexy and excessive daytime sleepiness. NT1 probably arises from autoimmune destruction of orexinergic neurons in the hypothalamus. These neurons are the only known producers of the neuropeptides orexin A and B, which are involved in the regulation of sleep and wakefulness. NT1 is often accompanied by comorbidities such as obesity, type 2 diabetes, hormonal disorders, depression, and anxiety. Gut microbiota affects the quality of sleep by the production of various metabolites. It is considered that it may be involved in the pathogenesis of NT1 or in the development of related comorbidities. In our study, we analyzed the gut microbiota composition of 41 NT1 patients and 32 healthy controls using next-generation sequencing. The diversity of patients' gut microbiota did not differ significantly from healthy controls. In patients, we revealed a positive correlation between the abundance of the bacterial family Coriobacteriaceae, BMI, and the disease duration. Besides, we observed a negative correlation between the Coriobacteriaceae family and cholesterol levels, suggesting that these bacteria are involved in host lipid metabolism. Compared to healthy controls, a higher abundance of bacteria from the families...
|
|
|
Rat gut microbiome composition and metabolic faecal markers upon morphine withdrawal
Mičke, Bianka ; Novotný, Jiří (advisor) ; Pácha, Jiří (referee)
The primary purpose of this pilot study was a long-term monitoring of the gut microbiome composition and fecal markers of metabolism in rats following the completion of 10-day intraperitoneal administration of increasing morphine doses (from 10 to 50 mg/kg/day) and in the corresponding control groups of rats that didn't administrate morphine. This study involved the introduction of new methods for microbiome and metabolome research, statistical evaluation of results and interpretation of data, or hypothesis to explain the effects of morphine on the gut microbiome and fecal metabolome composition compared to the resulting data of similarly oriented studies. The actual experiment was conducted on male Wistar rats aged 2 months and weighing approximately 300 g, which were maintained on a standard chow diet. The analysis and evaluation of the resulting data showed that there were changes in the composition of the gut microbiome and fecal metabolome in the experimental group compared to the control group during the reporting period but the induced changes were rather temporary. Further studies should be performed using a significantly larger experimental and control group as well as higher time series granularity. Keywords: morphine, opioids, withdrawal, gut microbiome, faecal metabolome
|
|
| |
|
|
The effect of gluten-free diet on β-cell residual capacity, immune function and gut microbiome in children with newly diagnosed type 1. diabetes
Neuman, Vít ; Šumník, Zdeněk (advisor) ; Pelikánová, Terezie (referee) ; Škvor, Jaroslav (referee)
The effect of gluten-free diet on β-cell residual capacity, immune function and gut microbiome in children with newly diagnosed type 1. diabetes Abstract The pathophysiology of the onset and progression of type 1 diabetes (T1D) is not fully understood. Gluten has a proinflammatory effect on the immune system and is therefore considered as one of the factors affecting the onset and progression of T1D. The aim of the thesis is to allow a complex insight into the role of the GFD on the residual β-cell capacity, T1D control, gut microbiome, gut permeability, subtypes of immune cells and the effect of gut microbiome transfer into germ-free non-obese diabetic (NOD) mice on the incidence of diabetes. On the group of 45 children with T1D (26 intervention group, 19 control group) we proved the association of the GFD with slower decrease of β-cell residual capacity (the difference in the trend of C-peptide decrease 409 pmol/l/year; p = 0,04) and lower HbA1c (by 7,8 mmol/mol; p=0,02). We also described the changes in the gut bacteria that were differentially abundant after the administration of the GFD and the changes in abundance of the regulatory and effector immune cells. We showed there was no change in the gut permeability with respect to the study group. We also proved that the transfer of human gut microbiota...
|
guest ::
