Obesity and associated metabolic disorders, called as "metabolic syndrome", currently represent a major social and economical problem of public health. From the energy balance point of view, long-lasting energy surplus leads eventually to massive accumulation of energy stores resulting in various adverse effects on metabolism and health. General goal of the thesis was to examine these metabolic disorders at cellular and whole-body level using suitable mouse models. The main focus was on the most metabolically active tissue, namely skeletal muscle, liver and adipose tissue and on the regulatory roles of AMP-activated protein kinase (AMPK) and leptin in the energy metabolism. The whole thesis is based on four published studies. Two studies were focused on skeletal muscle. In the first study, we proved the involvement of leptin and AMPK in the metabolic response to high-fat diet-feeding. We described a mechanism of muscle non- shivering thermogenesis based on enhanced lipid catabolism, which contributes to the genetically-determined resistance of inbred A/J mice to obesity. Such mechanism was not operating in obesity-prone C57BL/6 mice. In the second study, performed using C57BL/6 mice, we have described beneficial effect of combination treatment using n-3 polyunsaturated fatty acids (n-3 PUFA) of...

Farnesoid X receptor is mostly expressed in liver cells and its activation may be used for the treatment of cirrhosis causing diseases, especially biliary cirrhosis and nonalcoholic steatosis. These two latter diseases are most common in developed countries and, as of date, no effective treatments are available. Therefore, the aim of this project is the design and synthesis of novel bile acid analogues with subsequent biological evaluation towards farnesoid X receptor. Thus, a series of new compounds were designed using computational modeling studies and chemical synthesis was done to develop structure-activity relationships. Chemical structure analysis and purity was confirmed by conventional analytical methods. Finally, synthetic compounds were profiled against farnesoid X receptor in collaboration with the Pharmaceutical faculty of Charles University in Hradec Králové. Keywords: farnesoid X receptor, FXR, bile acids

This thesis deals with the composition of milk fat and the proportion of fatty acids in bovine milk fat. Then we evaluated factors that affect the fatty acids in milk fat - in particular the effect of diet. In results is as well mentioned one of the biological factors - the effect of the breed.

Changes occur in milk during the technological processing of raw milk, which also affect the properties of milk fat. Dairy products may have different properties compared to the raw milk. Chemical and microbial processes can alter the presence and distribution of individual fatty acids and thus influence the nutritional value of the product. The aim of this thesis was to assess the presence of fatty acids in milk fat of goat milk and to evaluate differences in the spectrum of fatty acids in goat milk and yoghurt produced from it.

The dissertation "The Influence of Genotype of Leptin Gene on Qualitative Characteristics of Beef" describes the effect of polymorphisms of gene of leptin on selected qualitative, morphometric and weight indicators of beef and carcass. The analysis was carried out on 333 bulls of Czech Fleckvieh, which were genotyped (by PCR/RFLP method) of chosen locus. This locus is associated with qualitative changes in beef according to previous foreign studies. The weight of carcass, fore and hind quarter of the right half of the carcass, the weight of the individual tissues (meat, bone, and fat) and the weight of main meaty parts from the right half of carcass were measured. Before the dissection chosen morphometric indicators were measured. After the dissection, a sample of the musculus longissimus lumborum et thoracis was taken and then analysed in the laboratory. Basic chemical composition (dry matter, fat content, protein, and ash), muscle fibers diameter and fatty acid profile was determined. In addition, pH, added water holding capacity, colour (CIE Lab colour coordinates) were analysed both for one-day post-mortem and after 14 days of ageing. The shear force (using the Warner-Bratzler probe) was evaluated at the same time intervals as for both raw and heat-treated samples by grilling. The studied LEP polymorphism had a statistically significant effect on the weight of the hot carcass, the weight of right half of carcass and fore and hind quarter. LEP polymorphism significantly affected the proportion of meat on the right half of carcass, the weight of the bones and total weight of the I. class meat, and the weight of the I. class meat in the fore quarter. Further, the effect of LEP polymorphism on the weight of boneless round, boneless chuck, plate, flank, rib, hind shank, and meat trimmings of fore quarter was found. In a group of morphometric indicators, the effect was significant on lengths of round, fullness of round and round circumference. In the case of chemical composition, the effect of LEP polymorphism on the intramuscular fat content was significant. From the qualitative indicators, the effect was significant on the pH value and added water holding capacity, both one-day post-mortem and after 14 days of ageing. In the case of tenderness, the effect on shear force of heat treated, non-aged meat was significant. From the indicators describing colour, a statistically significant effect on the indicator of lightness was found in the case of unconditioned meat and after 14 days of ageing the effect was significant on the indicator characterising yellow colour and the colour saturation. Determination of fatty acid profile was carried out by gas chromatography. The effects of studied polymorphism and differences between LEP genotypes were found in myristic, palmitic, palmitoleic, linoleic, -linolenic, -linolenic, conjugated linoleic, eisocapentaenoic, docosatetraenoic, docosapentaenoic both n-6 and n-3 and docosahexaenoic acids. From aggregated indicators, the statistical significant effect of LEP polymorphims on PUFA content, omega-3 fatty acids content, and omega-6/omega-3 fatty acids ratio was found. In connection with other candidate gene loci influencing the quality of beef, the results of dissertation can be used in the preparation of breeding schemes aimed at the production of quality breeding animals, highlighting the higher quality standards of the produced meat.

Global studies show the effect of polymorphism of selected genes on dairy production and fatty acid spectrum. The aim of the diploma thesis was genotyping of candidate FASN locus with a focus on milk yield and fatty acid spectrum depending on genotype. The thesis describes the characteristics of cow's milk, milk fat and fatty acids in milk fat. Furthermore, the thesis deals with the genome of cattle and the potential influence of polymorphism of candidate genes affecting fatty acids of milk fat. Genotypes for FASN were determined by the PCR-RFLP method, the milk yield of selected dairy cattle was statistically evaluated according to the milk production indices for 1st lactation in individual breeds, and the determination of fatty acids was performed by spectrophotometry followed by statistical evaluation. The resulting genotypes in selected breeds were only two, the GG genotype with a higher relative frequency than the genotype AG. There is no statistically significant difference between FASN genotypes depending on the milk yield and the fatty acids spectrum.

The thesis deals with the assessment of proportion of fatty acids in milk fat on goat farm and watching the selected proportion of major fatty acids in the selected factors. Sampling took place between 2010 and 2011, were made three taking of milk in a different stage of lactation. Evaluation of fatty acids was carried out both within groups and for major acid alone. The thesis was also included evaluation of quality indicators and yield of goat milk.

Fat tissue plays a main role in the development of the metabolic syndrome. Many components of the metabolic syndrome may be improved by dietary arrangements, including an increased intake of n-3 PUFA. In addition to the positive effect of n-3 PUFA, a possible effect of a higher calcium intake on influencing weight loss and energy metabolism has also been discussed for a long time. In addition to nutritional factors, genetic factors significantly contribute to influencing weight and lipid and glucose metabolism. In study A, 40 obese women were observed during three weeks of weight reduction management. Women were randomly divided into two groups. The first group received yogurt enriched with n-3 PUFA, and the second group consumed yoghurt without the supplementation. The results show that low-dose supplementation with n-3 PUFA in yogurt in combination with a reduced energy intake increases n-3 PUFA content in serum lipids and prevents adverse changes in the composition of FA in serum after a short-term low-calorie diet. In study B, we monitored the influence of n-3 PUFA supplementation on short-term weight management with VLCD in 20 women with severe obesity, who were randomly divided into two groups. The first group received VLCD enriched with n-3 PUFA, the second group VLCD with a placebo. The addition of...

This diploma thesis deals with characterization of sea buckthorn oil. The sea buckthorn oil is frequently used as a food supplement and in dermatology. The first part summarizes the literature on sea buckthorn oil and its biological effects. In the experimental part, the thesis deals with the comparison of three commercially available preparates of sea buckthorn oils. We employed the basic characteristics of these oils, including the determination of peroxide value, iodine value, saponification value and acid value using titration methods. Spectroscopic measurements were used to further characterize the oils. The comparised sea buckthorn oil samples differed strongly in the peroxide value and in the stability during storage. In this respect, the oil from Relikt - Art Engel company had significantly lower value (2,95 mekv/kg) compared to other two oil samples studied from Elith Phito and Virde companies with peroxide values 12,68 and 8,97 mekv/kg. This value was also much less prone to increase during storage. A similar difference was also found in spectral and colorimetric characteristics of the oil samples, where this oil displayed much less optical density then the other two samples. This might be a result of different technology used for production of oils, or it may reflect some adulteration,...

The presented diploma thesis deals with the study of interactions between humic acids as the main component of soil organic matter with a model organic pollutant presented by cationic surfactant Septonex (which was expected to interact positively with humic acids due to its charge) through unconventional combination of dialysis and diffusion techniques realized in diffusion cells together with isothermal titration calorimetry capable of elucidating the nature of ongoing reactions from a thermodynamic point of view. The experiments were performed with a humic acid isolated by standard isolation procedure from Leonardite (1S104H) purchased from the International Society for Humic Substances, with humic acids isolated from lignite as well as modal chernozem. The aim of the submited diploma thesis is to assess the influence of carboxyl functional groups in the structure of humic acids to interactions with Septonex. For this reason, said samples of humic acids have been modified by selective methylation of their carboxyl functional groups, which can no longer participate in interactions with ionic substances. Results from diffusion cells and isothermal titration calorimetry confirmed the assumption that Septonex interacted with all types of unmodified humic acids more than with their methylated derivatives. Despite the available literature, it was surprising that the differences in the interaction of humic acids with Septonex were not diametrically different when comparing unmodified humic acids with their methylated derivatives. The extent of these interactions was assessed through the apparent equilibrium constant Kapp determined in the diffusion (dialysis) experiments and from the course of enthalpy curves from isothermal titration calorimetry. After the experiments and their evaluation, it can be concluded that humic acids and Septonex in their interactions, due to their structures, probably apply not only electrostatic interactions, especially through available carboxyl functional groups of humic acids and positively charged hydrophilic parts of Septonex molecules, but also a significant role have a hydrophobic effect, hydrogen bonds and Van der Waals forces.