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Interaction of 7,8-dihydroxyflavone with physiological metals
Streďanská, Aneta ; Mladěnka, Přemysl (advisor) ; Červený, Lukáš (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology and Toxicology Student: Aneta Streďanská Supervisor: prof. Přemysl Mladěnka, Pharm.D., PhD. Consultant: Zuzana Lomozová, Pharm.D., PhD. Title of thesis: Interactions of 7,8-dihydroxyflavone with physiological metals 7,8-dihydroxyflavone belongs to the phenolic substances collectively referred to as flavonoids. Flavonoids are bioactive components abundantly distributed in the daily diet with the ability to modulate health and disease through miscellaneous mechanisms including their antioxidant activity. However, they can also exhibit prooxidative effects under certain conditions. Due to this fact, which is related to individual factors, i.e. presence of various substitutions on the flavonoid come, it is therefore essential to understand the redox behavior based on the relationship between structure and effect and to understand their physiological, pharmacological and thus also potential toxic properties. The interaction with physiological metals is determined by the structure of the molecule through the dihydroxy moiety in positions 7 and 8. These mentioned metals are essential for many biochemical processes in biological systems. Their homeostasis is strictly regulated in the human body and disruption of this...
Study of intestinal transporters and their role in drug absorption
Huličiak, Martin ; Červený, Lukáš (advisor) ; Mladěnka, Přemysl (referee) ; Chládek, Jaroslav (referee)
Charles University, Faculty of Pharmacy in Hradec Kralove Training Workplace Department of Pharmacology and Toxicology Doctoral Degree Program Pharmacology and Toxicology Candidate Mgr. Martin Huliciak Supervisor Assoc. Prof. PharmDr. Lukas Cerveny, PhD. Advisor PharmDr. Ivan Vokral, PhD. Title of Doctoral Thesis Study of intestinal transporters and their role in drug absorption Oral drug administration is a widely accepted method due to its convenience and cost- effectiveness, with the small intestine playing a crucial role in drug absorption, thus affecting bioavailability and serving as a potential site for drug-drug interactions (DDIs). Efflux drug transporters such as P-glycoprotein (ABCB1) and breast cancer resistance protein (ABCG2), along with metabolizing enzymes such as cytochrome P450 3A4 (CYP3A4) at the intestinal barrier, significantly contribute to DDIs. Risk factors for DDIs include comorbidities, advanced age, and polypharmacotherapy. People living with HIV requiring antiretroviral therapy (ART) are particularly susceptible to DDIs, especially when co-infected with HCV. Antivirals, commonly used in ART and in the treatment of HCV infection, can interact with efflux transporters and CYP enzymes, affecting drug efficacy and safety. Therefore, this study mainly focuses on the DDIs of...
Study of gene expression regulation in kidneys.
Trávníčková, Aneta ; Smutná, Lucie (advisor) ; Mladěnka, Přemysl (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology and Toxicology Student: Aneta Trávníčková Supervisor: PharmDr. Lucie Smutná, PhD. Title of diploma thesis: Study of gene expression regulation in kidneys During evolution, each organism was forced to create its complex defense system to prevent the accumulation of endogenous and foreign substances, including drugs, in the body. These defense systems are composed of Phase I and Phase II enzymes and transport proteins. One of the main roles in the metabolism of endogenous and biotransformation of exogenous substances is ensured by the constitutive androstane receptor (CAR). This work aimed to determine the effect of activation of the human constitutive androstane receptor (hCAR) on the gene expression of drug transporters and biotransformation enzymes in the kidneys of humanized mice. Additionally, to examine the effect of CAR on the expression of selected genes in the HK2 cell line. In both cases, the isolation of mRNA was performed using the classic phenol-chloroform extraction followed by reverse transcription and the qRT-PCR reactions. Firstly, we studied the influence of CITCO, an agonist of hCAR, on the expression of biotransformation and transport protein genes in the kidneys of humanized mice. The expression...
Are currently used chelators of heavy metals also chelators of calcium and magnesium?
Skoupilová, Karolína ; Mladěnka, Přemysl (advisor) ; Šuťák, Róbert (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology and Toxicology Candidate: Karolína Skoupilová Supervisor: prof. Přemysl Mladěnka, Pharm.D., Ph.D. Title of diploma thesis: Are currently used chelators of heavy metals also chelators of calcium and magnesium? Calcium and magnesium are important elements for the human body. Calcium plays an important role in blood clotting and intracellular signalling, thus participating in muscle contraction and platelet aggregation, among other processes. Magnesium is a cofactor for many enzymes. A significant deficiency of both ions can manifest as disorders of heart rhythm and increased neuromuscular excitability. The aim of this study was to determine the chelating activity of currently used heavy metal chelators and to determine the stability of the indicator. First, the ideal pH for the experiment was determined. In the next step, the chelation rate of 21 known metal chelators was measured using an in vitro spectrophotometric method. Finally, the chelation of the most active calcium chelators was verified on platelet aggregation in a human blood sample. At the same time, the long-term stability of the indicator o- cresolphthalein complexone (CC) was determined. In the first step, pH 7.5 was chosen, which was the only one...
The influence of LDL-apheresis on aggregation of blood platelets, blood coagulation, and the effect of standard drugs.
Černotová, Veronika ; Mladěnka, Přemysl (advisor) ; Čečková, Martina (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Veronika Černotová Supervisor: prof. Přemysl Mladěnka, PharmD., Ph.D. Consultant: Lukáš Konečný, MSc. Title of diploma thesis: The influence of LDL-apheresis on aggregation of blood platelets, blood coagulation and the effect of standard drugs LDL-apheresis is a method that removes LDL-cholesterol (LDL-C) from the blood. It is used to treat familial hypercholesterolemia (FH), a genetic disorder causing high LDL-C levels and an early development of cardiovascular diseases. Blood platelets and coagulation system play an important role in these diseases and their activity is also affected by lipids. The aim of this thesis was to analyze possible differences in platelet aggregation and blood coagulation in patients suffering from FH. Two methods of treatment in this group were compared - lipid apheresis and PCSK9Ab (proprotein convertase subtilisin/kexin type 9 monoclonal antibodies). The observed parameters were also compared with age-matched healthy volunteers. Our cohort consisted of 15 patients and 15 healthy donors. Six patients were treated with lipid apheresis and also PCSK9Ab, six subjects only with PCSK9Ab. Platelet aggregation was measured with an impedance aggregometer using 7 different...
Evaluation of gene expression of selected ABC and SLC transporters in the HTR-8/SVneo cell line during stimulation with pro-inflammatory cytokines
Pokorná, Petra ; Čečková, Martina (advisor) ; Mladěnka, Přemysl (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Petra Pokorná Supervisor: Assoc. Prof. PharmDr. Martina Čečková, Ph.D. Consultant: Mgr. Simona Dudičová Title of diploma thesis: Evaluation of gene expression of selected ABC and OATP transporters in the HTR-8/SVneo cell line during stimulation with pro-inflammatory cytokines Placenta is the first and the largest fetal organ that gradually develops during pregnancy and plays an essential role in the development of the fetus. It fulfills the entire spectrum of functions, ensures the transport of nutrients to the fetus and the removal of waste substances back into the maternal circulation, protects the fetus from toxins, and at the same time fulfills a certain mechanical and especially immunological barrier between mother and fetus. One of the main functions of the placenta is the transport function which is made possible by membrane transporters present mainly in the syncytiotrophoblast layer of the placenta. Transporters in the human placenta can be divided into two families, SLC and ABC which are further divided into several subfamilies. The expression of transporters changes physiologically during pregnancy, but pathological conditions such as inflammation can also influence the expression....
Comparison of platelet aggregation in healthy population.
Minarovičová, Júlia ; Mladěnka, Přemysl (advisor) ; Hofman, Jakub (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Júlia Minarovičová Supervisor: prof. Přemysl Mladěnka, Pharm.D., Ph.D. Title of diploma thesis: Comparison of platelet aggregation in healthy population Platelets have an irreplaceable role in the process of aggregation. Nevertheless, their increased activity is associated with the development of many cardiovascular diseases. This process can be influenced by clinical used substances from the group of antiplatelet drugs, which differ in their effectiveness within the population. Within this study, platelet aggregation was tested using impedance aggregometry, whose principle is the change in electrical impedance between electrodes caused by the adhesion of activated platelets. Firstly, whole blood was incubated with clinically used antiplatelet drugs (ticagrelor, vorapaxar, and acetylsalicylic acid) and a flavonoid metabolite, 4-methylcatechol. Subsequently, a platelet aggregation inducer (ADP, thrombin receptor activating peptide 6 /TRAP/, collagen, arachidonic acid, ristocetin, U-46619, and platelet-activating factor /PAF/) was added, and the process was monitored for 6 minutes. The most potent inhibitor of the aggregation induced by arachidonic acid was acetylsalicylic acid in a concentration of 70 μM...
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...
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...
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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