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Relation between n-3 polyunsaturated fatty acids and cellular sensors of energetic state
Zouhar, Petr ; Flachs, Pavel (advisor) ; Pecina, Petr (referee)
The important factor in regulation of metabolic processes is regulatory proteins, which are able to react by feed-back to energetic state of the cell. Big attention is focused on the AMP activated kinase (AMPK) and NAD+ activated deacetylase SIRT1. These enzymes interact together and their stimulation increases mitochondrial biogenesis and fatty acid oxidation. Due to this it functions beneficially against the onset of obesity, insulin resistance and ageing. Fasting, exercise and some antidiabetogenic drugs act by these regulators. n-3 polyunsaturated fatty acids (PUFA) are also known because of their stimulative effects on mitochondrial biogenesis and -oxidation. Previous work of our group have showed that intake of higher dose of n-3 polyunsaturated fatty acids (PUFA) in diet lead to increase in activity of AMPK in white adipose tissue. New results presented in this thesis show that SIRT1 is essential for increase in expression of stimulators of -oxidation (PPAR etc) in response to n-3 PUFA in diet. n-3 PUFA futher improve the metabolic profile synergistically with calorie restriction probably through SIRT1.
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Influence of supplementation with n-3 polyunsaturated fatty acids on inflammatory markers in patients on long-term parenteral nutrition
Svěchová, Hana ; Novák, František (advisor) ; Meisnerová, Eva (referee)
SMOFLipid® is a commonly used fat emulsion for parenteral nutrition. We investigated how enrichment of SMOFLipid® with n-3 polyunsaturated fatty acids (PUFA) in a form of second fat emulsion, Omegaven® , changes fatty acid composition of total plasma phospholipids and erythrocyte phospholipids, cytokine concentrations in serum and in supernatant from in vitro whole blood culture stimulated with lipopolasaccharide (LPS) and we evaluated also changes in oxido- reductive balance. Eight patients on long-term home parenteral nutrition recieved both emulsions, SMOFLipid® (6 weeks) and SMOFLipid® +Omegaven® (4 weeks), one by one. We observed no significant differences in common laboratory and clinical parameters between these two types of diet. Enrichment of SMOFLipid® with Omegaven® led to an increase in eicosapentaenoic (EPA) and docosahexaenoic acid (DHA) in total plasma phospholipids and there was also an increse in proportion of EPA in erythrocyte phospholipids, while proportion of DHA remained unchanged. These changes were in both phospholipids of plasma and erythrocyte compensated for a decrease in proportion of linoleic and arachidonic acid (n-6 PUFA). There were elevated IL-6 and TNF-α serum concentrations in patients after both diets. There was a decrease in IL-6 production by 36% with SMOFLipid®...
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Characterization of metabolic effects of dietary omega-3 fatty acids in transgenic PPARα-humanized mice
Kalendová, Veronika ; Rossmeisl, Martin (advisor) ; Šilhavý, Jan (referee)
Obesity is tightly connected with metabolic diseases including insulin resistance, type 2 diabetes or dyslipidemia. Peroxisome proliferator-activated receptor (PPAR)-α is a key transcription factor involved in the regulation of lipid metabolism, while its activity is stimulated by a variety of hypolipidemic drugs. n-3 polyunsaturated fatty acids (PUFA), including eicosapentaenoic (EPA) and docosahexaenoic (DHA) acid, are endogenous ligands of PPARα, and they are used in the form of fish oil as dietary supplements in order to lower blood lipid levels and to prevent cardiovascular disease. Wax esters represent a novel lipid form of EPA and DHA, and according to recent studies they could exert more potent effects than the classical fish oil (i.e. triacylglycerols). Mice of the 129S1/SvImJ inbred strain were used in the present experiment, and included wild-type (WT) mice, as well as transgenic mice either with the exclusive expression of the human form of PPARα (hPPARα) or mice completely lacking PPARα (PPARα-KO). Mice were fed for 8 weeks the following diets: (i) a control low-fat diet, (ii) obesogenic high-fat diet (cHF), and (iii) the cHF diet supplemented with the n-3 PUFA concentrate in the form of wax esters isolated from marine zooplankton Calanus finmarchicus (ω3Cal). Mice were subjected to...
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The metabolism of an adipose tissue in mice with high-fat diet-induced obesity: the role of anatomical localization of the tissue and diet composition
Krsková, Kateřina ; Janovská, Petra (advisor) ; Behuliak, Michal (referee)
Regulation of the flow of fatty acids (FA) by futile cycle (TAG/FA cycle) in white adipose tissue (WAT) is an important mechanism of controlling metabolism of FA and therefore its regulation is in the interest of research as a possible therapeutic target in the treatment of obesity and insulin resistance. The study of the murine model suggests that the treatment of the n-3 PUFA with mild caloric restriction (CR) probably induces the TAG/FA cycle mainly in epididymal depot. It also reduces inflammation in WAT and the risk of cardiovascular diseases. We focused on monitoring the gene expression encoding key enzymes of the TAG/FA cycle (PEPCK, ATGL, HSL, DGAT1 and DGAT2) in dorzolumbar (DL), gonadal (GON) and mesenteric (MEZ) depot in a murine model C57BL/6 using qPCR. We were interested in the influence of the composition of fats in the diet, the influence of administration of n-3 PUFA with combination of 10% CR and the difference of gene expression among depots of WAT. The results indicate that the supplementation of high-fat diet with n-3 PUFA contributes mainly to reduction of gene expression for DGAT2 and the combination of n-3 PUFA and CR increases expression of genes influencing the TAG/FA cycle. In MEZ unlike GON and DL fat depot were no significant differences in gene expression, while the different...
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Influence of supplementation with n-3 polyunsaturated fatty acids on inflammatory markers in patients on long-term parenteral nutrition
Svěchová, Hana ; Novák, František (advisor) ; Meisnerová, Eva (referee)
SMOFLipid® is a commonly used fat emulsion for parenteral nutrition. We investigated how enrichment of SMOFLipid® with n-3 polyunsaturated fatty acids (PUFA) in a form of second fat emulsion, Omegaven® , changes fatty acid composition of total plasma phospholipids and erythrocyte phospholipids, cytokine concentrations in serum and in supernatant from in vitro whole blood culture stimulated with lipopolasaccharide (LPS) and we evaluated also changes in oxido- reductive balance. Eight patients on long-term home parenteral nutrition recieved both emulsions, SMOFLipid® (6 weeks) and SMOFLipid® +Omegaven® (4 weeks), one by one. We observed no significant differences in common laboratory and clinical parameters between these two types of diet. Enrichment of SMOFLipid® with Omegaven® led to an increase in eicosapentaenoic (EPA) and docosahexaenoic acid (DHA) in total plasma phospholipids and there was also an increse in proportion of EPA in erythrocyte phospholipids, while proportion of DHA remained unchanged. These changes were in both phospholipids of plasma and erythrocyte compensated for a decrease in proportion of linoleic and arachidonic acid (n-6 PUFA). There were elevated IL-6 and TNF-α serum concentrations in patients after both diets. There was a decrease in IL-6 production by 36% with SMOFLipid®...
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Energetický metabolismus inbredních myších linií a jeho ovlivnění dietou
Kůs, Vladimír ; Kopecký, Jan (advisor) ; Nováková, Olga (referee) ; Mráček, Tomáš (referee)
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...
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Relation between n-3 polyunsaturated fatty acids and cellular sensors of energetic state
Zouhar, Petr ; Pecina, Petr (referee) ; Flachs, Pavel (advisor)
The important factor in regulation of metabolic processes is regulatory proteins, which are able to react by feed-back to energetic state of the cell. Big attention is focused on the AMP activated kinase (AMPK) and NAD+ activated deacetylase SIRT1. These enzymes interact together and their stimulation increases mitochondrial biogenesis and fatty acid oxidation. Due to this it functions beneficially against the onset of obesity, insulin resistance and ageing. Fasting, exercise and some antidiabetogenic drugs act by these regulators. n-3 polyunsaturated fatty acids (PUFA) are also known because of their stimulative effects on mitochondrial biogenesis and -oxidation. Previous work of our group have showed that intake of higher dose of n-3 polyunsaturated fatty acids (PUFA) in diet lead to increase in activity of AMPK in white adipose tissue. New results presented in this thesis show that SIRT1 is essential for increase in expression of stimulators of -oxidation (PPAR etc) in response to n-3 PUFA in diet. n-3 PUFA futher improve the metabolic profile synergistically with calorie restriction probably through SIRT1.
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