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Vliv přídavku quercetinu na výskyt kokcidií u králíků
Dvořáčková, Nikola
This thesis investigated the effect of the flavonoid quercetin on the coccidiosis oocyst counts in rabbits. At the same time, it also investigated the impact on weight, daily gains, feed conversation ratio, daily and total consumption, and biochemical blood parameters. The experiment lasted a total of 116 days. Two groups of six piece weaned rabbits each of the Japanese rabbit breed were created. The age of the rabbits was 35–149 days in the experimental group and 31–145 days in the control group. The average weight of rabbits at the beginning of the experiment was 267 g, and at the end, it was 2288 g. A special feed mixture containing 1.9% quercetin was prepa-red for the experimental group. The mixture was added in the amounts of 1, 2, and 4 g per day, depending on their equal weight. The addition of 0.01 – 0.04 g/rabbit/day of the flavonoid quercetin did not have a negative effect on the health status, performance parameters, and biochemical para-meters of the blood. The experimental group had a lower average number of oocysts (EPG) than the control group (quercetin = 328, control = 640). There was a statisti-cally significant effect of quercetin on the number of coccidia oocysts (P < 0.05), pro-bably through its antioxidant effect, supporting immune reactions, and thereby main-taining a healthy intestinal environment. Quercetin can be a potential substance for the prevention of coccidiosis.
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Study of the mechanisms of action of phenolic compounds on vascular smooth muscle
Alves Dias, Patrícia Alexandra ; Mladěnka, Přemysl (advisor) ; Kyselovič, Ján (referee) ; Štengl, Milan (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Training Workplace Department of Pharmacology and Toxicology Doctoral Degree Program Pharmacology and Toxicology Candidate Patrícia Alexandra Alves Dias, M.Sc. Supervisor prof. Přemysl Mladěnka, Pharm.D., Ph.D. Advisor assoc. prof. Jana Pourová, Pharm.D., Ph.D. Title of Doctoral Thesis Study of the mechanisms of action of phenolic compounds on the vascular smooth muscle Cardiovascular diseases including hypertension, coronary artery disease, peripheral artery disease, and cerebrovascular disease remain the leading cause of death worldwide. In addition, discouraging estimations have suggested a future increase in the number of cardiovascular patients. Thus, novel treatment modalities are clearly needed to prevent or reverse these epidemic trends. Phenolic compounds contain one or more hydroxyl groups bound to a benzene ring. This class of chemicals includes: a) natural compounds (e.g., dietary polyphenols and small phenolic metabolites) referred to as nutraceuticals due to their claimed health-promoting effects and b) synthetic compounds (e.g., bisphenols) which, on the contrary, have been suggested to negatively affect human health. Even if there are claims that polyphenol-rich diet is associated with cardioprotective effects, important...
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Effects of isoflavonoids and their metabolites on vascular smooth muscles in vitro and in vivo
Migkos, Thomas ; Mladěnka, Přemysl (advisor) ; Studenik, Christian (referee) ; Trejtnar, František (referee)
Charles University Faculty of Pharmacy in Hradec Kralove Department of Pharmacology & Toxicology Candidate: Thomas Migkos, M.Sc. Supervisor: Prof. Přemysl Mladěnka, Pharm.D, Ph.D. Consultant: Assoc. Prof. Jana Pourová, Pharm.D, Ph.D. Title of dissertation thesis: Effects of isoflavonoids and their metabolites on vascular smooth muscles in vitro and in vivo The dietary intake of flavonoids seems to be inversely related to cardiovascular mortality, in particular on coronary artery disease. The consumption of isoflavonoids, one class of flavonoids, has been increasing in the general population, especially due to the use of food supplements and a variety of isoflavonoid-rich foods. Although their bioavailability is low, they undergo extensive gastrointestinal metabolism by human bacteria, leading to smaller metabolites with a much higher degree of bioavailability. However, detailed studies on the impact of individual pure isoflavonoids on vascular system were mostly missing and much less was known for the effect of their colonic metabolites in this field. In the present study sixteen isoflavonoids, four metabolites and the racemic mixture of one of them were initially screened ex vivo for their vasorelaxant properties on rat aortas. The most potent of them, biochanin A, glycitein, O-desmethylangolensin...
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The influence of metabolites and their parent phenolic compounds on blood platelets
Hrubša, Marcel ; Mladěnka, Přemysl (advisor) ; Moťovská, Zuzana (referee) ; Kollár, Peter (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department: Department of Pharmacology and Toxicology Candidate: Mgr. Marcel Hrubša Supervisor: Prof. PharmDr. Přemysl Mladěnka, Ph.D. Title of dissertation thesis: The influence of metabolites and their parent phenolic compounds on blood platelets Acute cardiovascular events (ACEs), such as stroke and acute coronary syndromes encompassing acute myocardial infarction, are one of the main causes of cardiovascular mortality in the world. Current pharmacotherapy focuses primarily on secondary prevention of their recurrence, where antiplatelet drugs play a key role. These drugs reduce platelet hyperreactivity, which is present in the majority of cardiovascular and metabolic diseases, and significantly decrease the risk of ACEs. However, the palette of currently available drugs faces many issues, such as resistance, high variability in both pharmacokinetics and pharmacodynamics, serious side effects and the route of administration. This thesis firstly briefly summarizes the current knowledge of platelet physiology along with available antiplatelet drugs and their mechanism of action. Second part of the theoretical introduction is dedicated to polyphenolic compounds, as polyphenol-rich diet is associated with many beneficial effects, particularly...
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The impact of benzoic acids, metabolites of flavonoids, on the iron-catalysed Fenton reaction
Klenovičová, Alexandra ; Mladěnka, Přemysl (advisor) ; Karlíčková, Jana (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Alexandra Klenovičová Supervisor: Prof. Přemysl Mladěnka, PharmDr., Ph.D. Consultant: Zuzana Lomozová, Ph.D. Title of diploma thesis: The impact of benzoic acids, metabolites of flavonoids, on the iron-catalysed Fenton reaction Oxidative stress is a condition in which there is an increased production of free radicals that exceeds endogenous antioxidant activity and leads to damage of biomolecules. A number of human diseases are associated with oxidative stress. However the use of antioxidants has failed in clinical trials, but it is possible that the fact that antioxidants may preferentially exhibit prooxidant activity under elevated antioxidant concentrations in various pathophysiological conditions. Various in vitro and epidemiological studies have confirmed the presence of antioxidant and prooxidant properties in flavonoids. However, on the basis of their pharmacokinetics, it is evident that after their oral intake, significant metabolism in the colon takes place, where small phenolic substances are formed in interaction with the intestinal microflora. There is a possibility that the antioxidant and harmful prooxidant properties that have been attributed to flavonoids are in fact a...
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The influence of benzoic acids (metabolites of flavonoids) on the copper-triggered Fenton reaction and hemolysis
Harčárová, Patrícia ; Lomozová, Zuzana (advisor) ; Karlíčková, Jana (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacognosis and Pharmaceutical Botany Student: Patrícia Harčárová Supervisor: Zuzana Lomozová, MSc., Ph.D. Title of diploma thesis: Effect of benzoic acids (flavonoid metabolites) on copper catalyzed Fenton reaction and hemolysis Keywords: flavonoids, benzoic acids, copper, Fenton reaction, hemolysis Copper is a biogenic trace element that is present in several enzymes and proteins in the human body. The ability of copper to change its oxidation state is essential for its biological functions and enables enzymatic redox reactions in the organism. Homeostasis of copper is strictly regulated in the human body as its disruption can lead to the toxic effects of copper. Flavonoids are secondary plant metabolites that are a common part of our diet and their consumption has positive effects on our bodies. However, under certain conditions, they can also have a pro-oxidative effect, which is related to their ability to reduce transition metal ions. Flavonoids are massively metabolized in the human body before reaching systemic circulation into small phenolic substances including benzoic acids. Seven benzoic acid derivatives were tested as part of this thesis. Their influence on the production of hydroxyl radicals arising during the...
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The influence of metabolites and their parent phenolic compounds on blood platelets
Hrubša, Marcel ; Mladěnka, Přemysl (advisor) ; Moťovská, Zuzana (referee) ; Kollár, Peter (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department: Department of Pharmacology and Toxicology Candidate: Mgr. Marcel Hrubša Supervisor: Prof. PharmDr. Přemysl Mladěnka, Ph.D. Title of dissertation thesis: The influence of metabolites and their parent phenolic compounds on blood platelets Acute cardiovascular events (ACEs), such as stroke and acute coronary syndromes encompassing acute myocardial infarction, are one of the main causes of cardiovascular mortality in the world. Current pharmacotherapy focuses primarily on secondary prevention of their recurrence, where antiplatelet drugs play a key role. These drugs reduce platelet hyperreactivity, which is present in the majority of cardiovascular and metabolic diseases, and significantly decrease the risk of ACEs. However, the palette of currently available drugs faces many issues, such as resistance, high variability in both pharmacokinetics and pharmacodynamics, serious side effects and the route of administration. This thesis firstly briefly summarizes the current knowledge of platelet physiology along with available antiplatelet drugs and their mechanism of action. Second part of the theoretical introduction is dedicated to polyphenolic compounds, as polyphenol-rich diet is associated with many beneficial effects, particularly...
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Alkaloid and flavonoid content in Fontinalis antipyretica Hedw.
Ptáčníková, Lucie ; Martin, Jan (advisor) ; Tůmová, Lenka (referee)
Lucie Ptáčníková, The volume of alkaloids and flavonoids in Fontinalis antipyretica, Thesis, Charles University in Prague, Faculty of Pharmacy in Hradec Králové, thesis tutor: PharmDr. Jan Martin, PhD., Hradec Králové, 2012, 55 pages. Thesis called "Content of alkaloids and flavonoids in Fontinalis anitpyretica" establishes alkaloids and flavonoids and identifies one substance of these alkaloids in the above-mentioned water moss. The main purpose of this thesis was to obtain samples of Fontinalis antipyretica from selected locations in the Czech Republic (Ledce, Rychnovek, Kunvald). Next purpose was to determine alkaloids and flavonoids of collected material, isolated one substance of alkaloid character and verify identity of selected alkaloid. The content of alkaloids and flavonoids was determined by using the high-performance liquid chromatography (HPLC). The results show that β - carboline alkaloid harmin was determined by consensus UV spectrum and retention time with standard. Consequently flavonoids called myricetin and hyperosid was determined. Identity of β - carboline alkaloid harmin was verified by using NMR analysis. Keywords: alkaloids - harmalol - harmin - Fontinalis antipyretica - flavonoids
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Sulfates as phase II metabolites of natural phenolic compounds
Hetman, Anastasiia ; Mladěnka, Přemysl (advisor) ; Siatka, Tomáš (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Anastasiia Hetman Supervisor: Assoc. Prof. Přemysl Mladěnka, PharmD., Ph.D. Co-supervisor: Assoc. Prof. Kateřina Valentová, Ph.D. Title of diploma thesis: Sulfates as phase II metabolites of natural phenolic compounds Natural monophenolic compounds, which both occur in plants and are formed during gut microbiota metabolism of polyphenols, are absorbed and pass through phase II metabolism. This results in the formation of various conjugated metabolites, such as sulfates, whose biological activity was not studied as yet. This work focused on the preparation and isolation of pure sulfated metabolites of phenolic compounds, namely 4- methylcatechol, protocatechuic, homoprotocatechuic, and 2,3,4-trihydroxybenzoic acid, and phloroglucinol, using the aryl sulphotransferase from Desulfitobacterium hafniense. As a result, two sulfated products of sufficient purity were prepared, namely 4- methylcatechol-O-sulfate (an inseparable mixture of 4-methylcatechol-2-O-sulfate and 4- methylcatechol-1-O-sulfate) and phloroglucinol-O-sulfate. Their antioxidantactivity was evaluated and compared with the activity of the parent compounds using the following six in vitro tests: DPPH (1-diphenyl-2-picrylhydrazyl) and...
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Effect of dihydromyricetin on hepatic ethanol metabolism
Boubínová, Gabriela
Dihydromyricetin (DMH) is a natural flavonoid compound with positive effects on the human organism. In traditional Chinese medicine, plants containing DMH were used to treat liver diseases and to reduce alcohol intoxication. The effects of DHM on ethanol metabolism are not yet completely understood. Effects of DHM during alcohol intoxication were studied on primary hepatocytes of rats. DCFDA and DHR probes were used to prove that DHM (depending on concentration) reduces the number of reactive oxygen and nitrogen species in primary hepatocytes. However, the hepatoprotective effects of DHM were not achieved when presence of the alanine aminotransferase (ALT) was used to measure the damage of cells exposed to alcohol. Further, the effects of DHM on alcohol metabolism were studied in vivo. Rats were administered with single dose of ethanol or ethanol combined with DHM. Measured blood levels of ethanol and acetaldehyde show that DHM has no effects on the rate or levels of alcohol metabolism. The effects of DHM were also studied with repeated alcohol administration. In the group that was administered also DHM, increased blood levels of ethanol were measured. This points that DHM slow down the metabolic rate of ethanol. Obtained results did not prove any positive effects of DHM on alcohol metabolism....
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