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The role of gut microbiota and HPA axis in childhood
Trunečková, Naděžda ; Kaňková, Šárka (advisor) ; Kreisinger, Jakub (referee)
The microbiota-host relationship is a complex system of interactions, which has evolved over thousands of years. Colonization of the gastrointestinal tract begins in prenatal period, continues after birth, and can be disrupted by different factors like a mode of delivery, lactation, or antibiotics. Main development of the intestinal microbiota and the central nervous system takes place in the first two or three years of life. The microbiota and the brain can mutually influence their development. For the communication is used the microbiota-gut-brain axis, which includes the neural, endocrine, metabolic and immunological pathways. Exposure to stress, whether in the prenatal period or in the first few years of life, can have a negative impact on the composition of the intestinal microbiota and the developing brain, including areas associated with the regulation of the HPA axis - one of the main mechanisms of stress regulation, which includes all interactions between the hypothalamus, pituitary gland and adrenal glands. Dysregulation of the microbiota-gut-brain axis can affect our response to stress, cognitive function, and emotions. The modified HPA axis response can affect our physical and mental health. It is associated with immune system disorders, behavioural disorders, social integration...
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Sexual dimorphism of rat gut microbiota composition and intestinal immunity
Kalousová, Pavla ; Kovařík, Miroslav (advisor) ; Jílek, Petr (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Biological and Medical Sciences Candidate: Pavla Kalousová Supervisor: PharmDr. Miroslav Kovařík, Ph.D. Title: Sexual dimorphism of rat gut microbiota composition and intestinal immunity Background and Aim: Many factors can influence the composition of gut microbiota and the immune system. It is well-known that one of those factors is sex. This sexual dimorphism can lead to a specifically adjusted treatment of diseases for different gender and nutritional interventions. This study focuses on analysing sexual differences in gut microbiota and intestinal immunity in adult rats. Methods: Caecal content from 12-week-old female and male Wistar rats were collected and analysed by DNA-sequencing technique to characterize microbiota composition. ELISA test was performed to quantify the concentration of IgA in faeces and gut wash. Flow cytometry determined the concentration of IgA-coating bacteria in faecal samples. Results: Metagenomic analysis revealed that female gender presents 1 phylum, 4 families, 13 genera, and 13 species which are not present in male rats. Only one male-specific colonization was observed at the species level. Quantitative analysis showed a higher proportion of Firmicutes phylum in males which was associated with...
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Impact of pesticides on the gut microbiota of animals
Stehlík, Michal ; Rada, Vojtěch (advisor) ; Salmonová, Hana (referee)
Pesticides are substances used to control plant and animal pest in agriculture. They are very significant and important factor in both production and revenues. Nowadays it is almost impossible for farmers to dispense without these substances but their presence in the soil does not bring only benefits. About pesticides it is generally known that they may adversely affect either on the ecosystem or the human or animal body. As the result many substances had been banned from market. Pesticides and their residues are subject to many controls and laboratory analysis in order to prevent their negative effects.
The aim of the thesis was to test the effect of pesticide (Roundup) on gut microorganisms. For the experiments we used bovine fecal samples and pure bacterial cultures isolated from various domestic animals for the testing of susceptibility to Roundup. We have determined specific growth rates of pure cultures cultivated on three different concentrations of Roundup and total counts lactobacilli, enterococci, E. coli and coliform bacteria of bovine feces cultivated on six different concentrations of Roundup
In the first experiment, no correlation has been found between the concentration of glyphosate (active substance of Roundup) and counts of bovine intestinal bacteria. The effect of glyphosate on the growth of intestinal bacteria was visible at the second attempt. At the highest concentration of glyphosate 17 g/L. Growth curves reached considerably lower levels here than at lower concentrations of glyphosate. Control samples and the samples on the concentration of glyphosate 1.7 mg/L and 0, 17mg/L increased similarly in most cases. This implies that in these concentrations there was no inhibition of bacteria whatsoever. The least susceptible genera to glyphosate were lactobacilli. The highest susceptibility to glyphosate was detected in bovine bacteria and the lowest in chicken bacteria.
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Characterization of bifidobacteria and lactobacilli isolated from intestinal tract of wild pigs
Šimurka, Julius ; Rada, Vojtěch (advisor) ; Švejstil, Roman (referee)
The microbiota of the gastrointestinal tract is considered as "acuqrated organ" located in a host organism. There are many performs of specific functions. The microbiota composition changes during the life of the individual, depending on his environment and nutrition. The process of identification and characterization of the bacteria from the intestinal microbiota is an important prerequisite for understanding the function of this "acuqrated organ".
This work deals with the anatomy and physiology of the digestive tract (DT) of pigs and evolutionary and eating differences of wild and domesticated pig, for understanding the natural environment of bacteria from DT, which in turn affects the bacterial diversity of the intestinal microbiota. Also mentioned is the process of domestication, which influenced the present form of domestic pig. The work includes the characteristics of lactobacilli and bifidobacteria, which contains the descriptions, taxonomy, metabolism and habitats. The work also shows the insulating media used in practice for the isolation of bifidobacteria and lactobacilli from DT of pigs and methods of their identification and related methods of characterization.
The available literature confirms the differences in the composition of microbiota DT between wild and domesticated pig, that correlate with other studies which study microbiota diversity of other domesticated and wild animals. The diversity studies of humans microbiota, also confirms the broad spectrum of bacterial species in primitive tribes of humans compared with urbanized man.
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Bifidobacteria of intestinal tract of exotic animals
Máčalíková, Tereza ; Vlková, Eva (advisor) ; Salmonová, Hana (referee)
The main topic of the bachelor thesis is description of occurence of bifidobacteria in the gastrointestinal tract of exotic animals and insect.
Afterwards was described a role of probiotic bacteria and influence of nutrition on their occurence. The goal of the practical part of the bachelor thesis was genus-level identification of bifidobacteria in feces samples of exotic animals. After the bacteria cultivation on selective agars, isolates were collected and detection of the enzyme fructose-6-phosphate phosphoketolase were made.
Bifidobacteria were found just in two samples from analyzed animals.
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Impact of pesticides on the gut microbiota of human
Kočová, Kateřina ; Rada, Vojtěch (advisor) ; Jakub, Jakub (referee)
Pesticides are substances or mixtures of substances used in agriculture against pests (animals, plants and parasitic fungi), who damage the crops, stocks of agricultural products, food and reduce livestock utility or threaten human health.
The thesis consists of two parts. The first (theoretical) part describes composition and function of gut microbiota; pesticides and their classification, environmental transport and effects of these substances on human health, and glyphosate as the active substance of herbicide Roundup, its mechanism of action, environmental fate and proven effects of glyphosate on human.
The aim of second (practical) part of this thesis was to test impact of pesticide Roundup on the gut microorganisms of human. The impact of pesticide was tested in in vitro pure cultures. Roundup was added in concentrations of glyphosate 17 g/L, 1,7 g/L and
0,17 g/L to the complex media and after cultivation the growth of microorganisms was evaluated. The next samples of stool were collected from human volunteers; these were cultivated similarly in the complex media with different concentrations of glyphosate. The total numbers of microorganisms, bifidobacteria, lactobacilli, enterococci and coliformn bacteria were defined after cultivation.
When the pesticide was tested in pure cultures, concentration of 17 g/L glyphosate significantly inhibited total bacterial growth (P < 0.05), at lower concentrations no difference was observed. The cultivated microorganisms from samples of stool demonstrated only that bifidobacteria are sensitive to glyphosate at the highest used concentration of this pesticide compared with the control sample.
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Clostridium butyricum as a probioticum
Veselá, Jana ; Rada, Vojtěch (advisor) ; Pechar, Radko (referee)
Probiotics are live microorganisms that, when administered in adequate amounts, confer a health benefit on the host. Evidence of positive effects of probiotics is rapidly expanding in gastroenterology. Probiotics find use in antibiotic-associated diarrhea, gastroenteritis and lactose intolerance.
Many different strains of bacteria are considered as probiotic, including clostridia. The most used probiotics are Lactobacillus and Bifidobacterium species. But there are also suggestions that some Clostrium butyricum strains could be also probiotic.
Aim of this study was therefore to evaluate the effectiveness of Miya-Gold (a feed additive containing viable spores of probiotic Clostridium butyricum MIYAIRI 588 strain as an active substance) to the improvement of feed conversion, average daily gain and final body weight in the chickens for fattening and also to observe the improvement of the stability of the gut and crop microbiota.
We found statistically significantly higher (P < 0.05) average weights of individuals in Miya-Gold group than in the control group at the day 7, 10, 20 and 49. By the analysis of microbiota we found at the day 42 statistically significantly lower (P < 0.05) amounts of Escherichia coli in the caecum and Escherichia coli and coliform bacteria in the crop and also lower pH in the crop in the Miya-Gold group.
The analysis of short-chain fatty acids was also performed and we found statistically significantly higher (P < 0.05) amount of butyrate in the caecum of Miya-Gold group.
The results indicate the ability of Miya-Gold to affect positively the performance and the intestinal microbiota of broiler chickens.
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