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Characterization of flubendazol reduction in human in vitro
Štěpánková, Jana ; Szotáková, Barbora (advisor) ; Novotná, Eva (referee)
ASBSTRACT Charles University Faculty of Pharmacy in Hradec Králové Department of Biochemical Sciences Candidate: Mgr. Jana Štěpánková Supervisor: Prof. Ing. Barbora Szotáková, Ph.D. Title of Thesis: Characterization of flubendazol reduction in human in vitro Flubendazole (FLU) is an anthelmintic of the benzimidazole type used as a treatment or prophylaxis of helminthoses in livestock and wild animals. FLU is also registered for the treatment of parasitic diseases caused by intestinal nematodes in humans. Its mechanism of action lies in its specific binding to tubulin, which disrupts the structure and function of microtubules for the therapy of parasitosis in humans. The advantage of this drug is also the low systemic toxicity. That is why the anticancer activity of FLU is now under study. The aim of this rigorous work was to characterize the reduction of FLU in human liver subcellular fractions as this information is still lacking in available literature. Stereospecificity, subcellular localization, preference of coenzymes, enzyme kinetics of FLU reduction, and activity of enzymes involved in FLU reduction were studied in this project. Measurement results have shown that FLU is predominantly reduced in cytosol and nicotinamide adenine dinucleotide phosphate reduced (NADPH) coenzyme is preferred. FLU...
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The effect of natural compounds on transport by OATP drug transporters
Zemčíková, Lucie ; Trejtnar, František (advisor) ; Mičuda, Stanislav (referee) ; Szotáková, Barbora (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Pharmacology and Toxicology Candidate: MSc. Lucie Zemčíková Supervisor: Assoc. Prof. PharmDr. František Trejtnar, CSc. Title of doctoral thesis: The effect of natural compounds on transport by OATP drug transporters OATP membrane transporters belong to carrier proteins responsible for transporting certain drugs (e.g. hypolipidemics from the group of statins) and other xenobiotics across the biological membranes and tissue barriers within the body. These transport proteins play an important role in pharmacokinetic processes such as absorption, distribution and elimination. The potential modulation of their transport function by natural compounds commonly present in plant food or food supplements may result in the changes of the concentration of their substrate (drug) in the cells and body fluids, that may affect the effect and toxicity of these drugs. The aim of this study was to obtain data on the interactions of selected natural compounds with human transporters OATP2B1 and OATP1A2 and their ability to affect drug transport mediated by these transporters. These two OATP transporters are involved in the drug uptake especially in organ barriers important for pharmacokinetics. For the study natural compounds from the group of...
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Effect of parasite on activity of biotransformation and antioxidant enzymes in host intestine
Mládková, Zuzana ; Szotáková, Barbora (advisor) ; Skálová, Lenka (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Biochemical Sciences Candidate: Zuzana Mládková Supervisor: prof. Ing. Barbora Szotáková, Ph.D. Title of diploma thesis: Effect of parasite on activity of biotransformation and antioxidant enzymes in host intestine Hymenolepis diminuta, known as a rat tapeworm, is commonly used in science as a model of Cestoda for studying physiology, biochemistry and drug metabolism in tapeworms. Recently, Hymenolepis diminuta has been studied for helminth-based therapy for a potential treatment of inflammatory bowel disease. The aim of this study was to determine how H. diminuta influences the activity of detoxification enzymes of the host intestine. At first 6 male rats (Wistar breed) were infected by cysticercoids of Hymenolepis diminuta previously isolated from the beetles Tenebrio molitor (intermediate host). At the same time the physiological saline solution was administered to the control group of 6 male rats. All rats were housed for 2 months in animal quarters with 12 h light/dark cycle. Thereafter, the tapeworms were removed from their intestines. Intestinal mucosa containing metabolic active enzymes was isolated. Subsequently, the subcelullar fractions were prepared and used for in vitro experiment. The activity of enzymes was...
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The effect of trabectedin on the cells derived from colorectal carcinoma
Bobek, Jaroslav ; Boušová, Iva (advisor) ; Szotáková, Barbora (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Biochemical Sciences Candidate: Jaroslav Bobek Supervisor: Doc. PharmDr. Iva Boušová, Ph.D. Supervisor specialist: RNDr. Veronika Skarková, Ph.D. Title od diploma thesis: The effect of trabectedin on the cells derivated from colorectal carcinoma Trabectedin is alkaloid, which occurs naturally in sea tunicate Ecteinascidia turbinata. Its mechanism of action consist of creation complexes with DNA, transcription factors and nuclears proteins. This cause blocade of transcription and defect of repair mechanism of DNA in cell. We can use it in therapy of some types of cancer, in this particular work we was researching influence on colorectal carcinoma. We tested this substance on two cancerous cell lines SW 480 - derivated from primary deposit of adenokarcinoma and SW 620 - metastatic line from lymph nodes from same patient. Prime cell cultures marked as 36B and 39B were secured from patients in University Hospital in Hradec Králové and their following cultivation. Both samples 36B and 39B were derived from the primary colon tumor deposit. On all cell lines was performed cytotoxicity assay and then was individualy calculated IC50. These values were used in migration assay for cells 36B and 39B. After treatment with trabectedin both...
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The effect of flavonoids on selected biotransformation enzymes
Procházková, Eliška ; Szotáková, Barbora (advisor) ; Skálová, Lenka (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Biochemical Sciences Candidate: Eliška Procházková Supervisor: Prof. Ing. Barbora Szotáková, Ph.D. Title of diploma thesis: The effect of flavonoids on selected biotransformation enzymes In recent years, catechins which belong to flavonoids have been studied polyphenolic constituents of green tea. Especially their beneficial effects on the human health are mostly studied. The popularity of dietary supplements with high levels of flavonoids is growing and thus they can affect a wide range of biotransformation enzymes and also the metabolism of many drugs. The aim of this diploma thesis was to find out how the selected catechins - catechin (C), epicatechin (EC), epicatechin 3-gallate (ECG), epigallocatechin (EGC), epigallocatechin 3-gallate (EGCG) and the green tea extract - polyphenon 60 (P) influence the viability of the Caco-2 cells and the activity and expression of the selected biotransformation enzymes in these cells - cytochromes P450 (CYP) isoforms 1A1, 1A2, and 3A, aldehyde reductase (AKR1A1), aldo-keto reductase 1C (AKR1C), carbonyl reductase 1 (CBR1), UDP-glucuronosyltransferase (UGT), sulfotransferase (SULT) and glutathione S-transferase (GST). The viability tests (NRU test and MTT test) proved that catechins (EGC,...
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Effect of sesquiterpenes on detoxifying enzymes in liver slices
Horáčková, Hana ; Szotáková, Barbora (advisor) ; Boušová, Iva (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Biochemical Sciences Candidate: Hana Horáčková Supervisor: prof. Ing. Barbora Szotáková, Ph.D. Title of diploma thesis: Effect of sesquiterpenes on detoxifying enzymes in liver slices Sesquiterpenes are secondary metabolites produced by higher plants, bacteria and fungi. They ensure the survival and competitiveness of plants. Sesquiterpenes are composed of three isoprene units. They possess anti-inflammatory, antimalarial, antibacterial, antiviral, antioxidant, analgesic, antifungal and anticancer activity. Sesquiterpenes, the main components of plant essential oils, have been used in folk medicine and as spices for years. The aim of this diploma thesis was to find out the effect of three structurally related sesquiterpenes α-humulene (HUM), β-caryophyllene (CAR), and β-caryophyllene oxide (CAO) on the activities of the main drug-metabolizing enzymes. Precision-cut tissue slices from the rat liver (Rattus norvegicus) were chosen as model system. Thickness of the slices was 200-250 μm and diameter 8 mm. Liver slices were pre-incubated for 30 minutes and then incubated for 8 and 24 hours. Samples of liver slices and incubation medium were taken upon replacing the medium after pre-incubation (time 0 hours) and then after 8 and 24...
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Purification of membrane bound enzyme DHRS7B
Mariničová, Valéria ; Novotná, Eva (advisor) ; Szotáková, Barbora (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Biochemical Sciences Candidate: Valéria Mariničová Supervisor: RNDr. Eva Novotná , Ph.D. Title of diploma thesis: The purification of the membrane-bound enzyme DHRS7B The membrane-bound DHRS7B enzyme, from the SDR (short-chain dehydrogenase/reductase) superfamily, is one of poorly characterized protein of the human organism. Despite the lack of information about its properties, it was observed in mice, where it is named to as PexRap, localized in peroxisomes. It is a peroxisomal reducing protein that uses NADPH as a cofactor. Its participates in biosynthesis of peroxisomal ether lipids during adipogenesis in mice. The role of human DHRS7B in cells or evantually in diseases has been only speculated and therefore it is in the focus of research. The aim of this work was to obtain the pure recombinant human DHRS7B enzyme prepared in Sf9 cells. It is a membrane protein, so it was necessary to find a suitable detergent that is able to remove the DHRS7B enzyme from the phospholipid membrane while preserving its activity. The most suitable detergent was DDM 1:1 (w/w) protein:detergent. Further step was its purification by affinity chromatography, the pure DHRS7B protein with a ketotifen reducing activity of 62 nmol/mg/min was obtained....
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Liver slices - model system for studying the effect of sesquiterpenes on detoxifying enzymes
Slavíčková, Zlata ; Szotáková, Barbora (advisor) ; Ambrož, Martin (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Biochemical Sciences Candidate: Zlata Slavíčková Supervisor: prof. Ing. Barbora Szotáková, Ph.D. Title of diploma thesis: Liver slices - model system for studying the effect of sesquiterpenes on detoxifying enzymes Sesquiterpenes are naturally occurring substances, mainly in higher plants as secondary metabolites. Together with monoterpenes, represent the main components of plant essential oils. Sesquiterpenes are biologically active compounds, among their biological activities belong anti-inflammatory, anti-carcinogenic, antioxidant, antibacterial and antimycotic effects. The aim of this diploma thesis was to find out the influence of three structurally similar acyclic sesquiterpenes cis-nerolidol, trans-nerolidol, and farnesol on the activity of selected biotransformation enzymes - aldo-keto reductase (AKR1A1, AKR1C9), carbonyl reductase 1 (CBR1), NAD(P)H-quinone oxidoreductase 1 (NQO1), cytochrome P450 (CYP1A1, CYP1A2, CYP2B, CYP3A), sulfotransferase (SULT), glutathione-S-transferase (GST), and UDP-glucuronosyltransferase (UGT) in rat liver. The influence of sesquiterpenes on selected enzymes was studied in precision-cut liver slices. The precision-cut tissue slices were obtained from rat liver (Rattus norvegicus, tribe...
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Effect of albendazole on the activity of selected enzymes in tapeworm Hymenolepis diminuta
Krejzová, Andrea ; Vokřál, Ivan (advisor) ; Szotáková, Barbora (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Andrea Krejzová Supervisor: PharmDr. Ivan Vokřál, Ph.D. Title of diploma thesis: Effect of albendazole on the activity of selected enzymes in tapeworm Hymenolepis diminuta The efficacy of anthelmintics used to treat diseases caused by helminths is not always sufficient, and in some cases, we are directly facing resistance to these drugs. Helminths, including tapeworms, are able to defend against the toxic effect of anthelmintics using several mechanisms. Xenobiotic metabolizing enzymes and transport proteins belong to these mechanisms. When xenobiotic metabolizing enzymes are induced, the efficacy of therapy may be significantly reduced. The effect of xenobiotic metabolizing enzymes on the drug resistance development has been already described in number of helminths. In tapeworms this information is still missing. Main aim of this study was to determine effect of drug albendazole on the activity of selected xenobiotic metabolizing enzymes in rat tapeworm (Hymenolepis diminuta). Tapeworms were incubated with albendazole (1 μM and 10 μM) for 24 hours. Then activities of selected enzymes in cytosol-like, microsome-like and mitochondria-like fractions were determined. This study is focused on...
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Modulation of biotransformation and antioxidant enzymes by selected natural compounds
Lněničková, Kateřina ; Szotáková, Barbora (advisor) ; Anzenbacherová, Eva (referee) ; Trejtnar, František (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Biochemical Sciences Candidate: Mgr. Kateřina LNĚNIČKOVÁ Supervisor: prof. Ing. Barbora SZOTÁKOVÁ, Ph.D. Title of Doctoral Thesis: MODULATION OF BIOTRANSFORMATION AND ANTIOXIDANT ENZYMES BY SELECTED NATURAL COMPOUNDS Public interest in various dietary supplements containing herbs, herbal extracts or isolated active compounds has increased significantly over past decades. Consumption of these supplements increases worldwide and they are often consumed in unreasonably high doses, as they are generally considered as safe. Upon the intake to organism, these compounds are, as other xenobiotics, modified mostly by xenobiotic-metabolizing enzymes and they could influence these enzymes at the same time. Potential modulation of xenobiotic-metabolizing enzymes' activity (induction or inhibition) can seriously affect pharmacokinetics of concomitantly administered drugs. Knowledge of the possible impact of natural compounds on the xenobiotic-metabolizing enzymes is essential for their safe use. The aim of this doctoral thesis was to study the effects of selected herbal extracts and their active chemical constituents on the activity and expression of xenobiotic-metabolizing and antioxidant enzymes. We have focused on the study of effects of...
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