National Repository of Grey Literature 45 records found  1 - 10nextend  jump to record: Search took 0.00 seconds. 
Role of drug transporters in placental transfer of entecavir
Křečková, Veronika ; Červený, Lukáš (advisor) ; Hofman, Jakub (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Veronika Křečková Supervisor: PharmDr. Lukáš Červený, Ph.D. Title of diploma thesis: Role of drug transporters in placental transfer of entecavir Entecavir (ETV), an analogue of guanosine, is a highly efficient anti-hepatitis B antiviral drug. It is the first-line therapy for both adults and children. Its use in pregnancy is limited due to a number of factors, including lack of data on placental pharmacokinetics. The placental transition of drugs is frequently controlled by drug transporters. ATP-binding (ABC) transporters, P-glycoprotein (P-gp), breast cancer resistance protein (BCRP) or multidrug resistance-associated protein 2 (MRP2) localized in the apical membrane of syncytiotrophoblast and pumping their substrates in the feto-maternal direction belong to most significant determinants of placental pharmacokinetics. Moreover placental transport of nucleoside-derived drugs can be affected by the activity of nucleoside transporters (NTs); equilibrative nucleoside transporters (ENTs) mediate facilitated diffussion, while the concentrative nucleoside transporters (CNTs) control active influx of their substrates. The aim of the diploma thesis was to describe the role of P-gp, BCRP, MRP2 and NTs (ENTs and...
Study of drug-drug interactions of antiviral drugs on intestinal transporters
Záboj, Zdeněk ; Červený, Lukáš (advisor) ; Vokřál, Ivan (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Zdeněk Záboj Supervisor: PharmDr. Lukáš Červený, Ph.D. Title of diploma thesis: Study of drugs interactions of antiviral drugs with intestinal transporters Sofosbuvir is an antiviral agent widely used in the treatment of chronic hepatitis C. This orally administered prodrug is a designed substrate of ATP-binding (ABC) efflux transporters, P- glycoprotein (ABCB1) and breast cancer resistance protein (ABCG2). ABCB1 and ABCG2 are important determinants of intestinal absorption and are the site of significant pharmacokinetic drug interactions, leading to changes in drug exposure. Pharmacokinetic drug interactions may be undesirable (increasing the toxicity of the treatment) or desirable (allowing dose reduction). Because sofosbuvir is often administered in combination regimens with other anti(retro)virotics, the aim of this thesis was to study the ability to enhance intestinal absorption of sofosbuvir. To study the pharmacokinetic drug interactions on ABCB1 and ABCG2, a widely established in vitro bi-directional transport method through a polarized monolayer formed by the Caco-2 cell line derived from colorectal cancer has been used. We analyzed the drug interactions of sofosbuvir on these efflux...
Study on impact of selected tyrosine kinase inhibitors on multidrug resistance mediated by ABC drug efflux transporters
Sýkorová, Martina ; Hofman, Jakub (advisor) ; Červený, Lukáš (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Martina Sýkorová Supervisor: RNDr. Jakub Hofman, Ph.D. Title of diploma thesis: Study on impact of selected tyrosine kinase inhibitors on multidrug resistance mediated by ABC drug efflux transporters Tyrosine kinases are an important class of enzymes controlling cell proliferation, carcinogenesis, apoptosis and cell differentiation. Deregulation of these enzymes can transform normal cell into a cancerous one. Blocking their function by tyrosine kinase inhibitors (TKi) is considered a promising treatment for various types of cancer. ATP-binding cassette (ABC) transporters form a family of transmembrane proteins that can transport a wide variety of substrates across biological membranes via ATP-dependent drug efflux pumps. They modulate drug pharmacokinetics, but on the other hand, lead to therapy failure due to overexpression in cancer cells. In our previous study, we evaluated inhibition properties of two selected TKi (alectinib, brivanib) in MDCKII cell lines (parent one and those transduced with human ABCB1, ABCC1 and ABCG2). Alectinib significantly inhibited ABCB1, ABCG2 but not ABCC1 transporter. Brivanib showed triple inhibition of all studied transporters. In the present work, we...
Study of the effect of novel antiretroviral drugs on carnitine transport in the placenta
Marková, Eliška ; Čečková, Martina (advisor) ; Červený, Lukáš (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Eliška Marková Suprevisor: doc. PharmDr. Martina Čečková, Ph.D. Title of diploma thesis: Study of the effect of novel antiretroviral drugs on carnitine transport in the placenta Nowadays, the antiretroviral treatment of HIV-positive pregnant women is the standard approach for restriction of transmission of HIV infection from mother to the fetus. In spite of necessity of this pharmacotherapy, it is important to know its safety and risks. For the correct fetal development and function of placenta it is (besides others) essential to ensure the optimal supply of L-carnitine, the key factor for oxidation of fatty acids from mother's blood to the placenta and fetal blood circulation. The deficiency of L-carnitine generally leads to significant metabolic changes in the cells and in it usually demonstrated with cardiomyopathies and myopaties. Published studies indicate higher incidence of cardiovascular diseases and cardiomyopathies in children born to mothers treated with antiretroviral therapy during pregnancy. Optimal transport of carnitine into the placental cells, is ensured due to the presence of functional transport protein OCTN2 in the apical membrane of trophoblast. The aim of this study was...
Study of gene regulation of nucleoside transporters in BeWo cell line
Strachoňová, Šárka ; Červený, Lukáš (advisor) ; Pávek, Petr (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Šárka Strachoňová Supervisor: PharmDr. Lukáš Červený, Ph.D. Title of diploma thesis: Studium of gene regulation of nucleoside transporters in BeWo cell line Nucleoside transporters (NTs) localized in syncytiotrophoblast control placental uptake of nucleosides. Dysregulation of NTs can disrupt nucleoside homeostasis with a negative consequences on placental and fetal development and can lead to a change in placental pharmacokinetics of nucleoside-derived drugs. Therefore, understanding the expression and function of NTs is necessary for effective and safe pharmacotherapy during pregnancy. The aim of this diploma thesis was to study the adenylate cyclase (AC) activated regulatory pathways of gene expression of concentrative nukleoside transporter 2 (CNT2). For this purpose, qRT-PCR and in vitro accumulation assays using the model substrate [3 H]-adenosine were employed. The human placental choriocarcinoma-derived BeWo cell line has been exposed to an AC activator, forskolin (50 µM), and/or inhibitors of AC/cAMP/PKA, AC/cAMP/MAPK (MEK1/2, p38 MAPK) signaling pathways, PKA inhibitor, KT 5720 (5 μM), an inhibitor of MEK1/2, U0126 (10 μM) and an inhibitor of p38 MAPK, SB202190 (10 μM). The...
Study of drug interactions with OATP family transporters using intestinal tissue slices
Čečková, Patrícia ; Vokřál, Ivan (advisor) ; Červený, Lukáš (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Patrícia Čečková Supervisor: PharmDr. Ivan Vokřál, Ph.D. Title of diploma thesis: Study of drug interactions with OATP family transporters using intestinal tissue slices An essential role in the action of orally administered drugs is their absorption through the intestinal barrier. It expresses a variety of transporters, including the OATP2B1 and OATP1A2 influx transporters, belonging to the SLC family. They are located on the apical membrane of enterocytes and allow the flow of endogenous and exogenous substances from the lumen of the intestines to the enterocyte. They affect not only the pharmacokinetics of drugs, but also their safety and efficacy. They represent sites of drug interactions with other drugs/food components that may altered drug efficacy or toxicity. Since FDA (The Food and Drug Administration) and EMA (European Medicines Agency) do not have intestinal OATP transporters included in their guidelines for preclinical studies, there is no single model of interaction study. The limitations of cell models and genetically modified organisms lead to the development of new methods such as the ex vivo method of precision cut intestinal slices (PCIS), which represents a tissue model...
Inhibitory effect of SPA70 on hPXR activation
Dohnalová, Klára ; Pávek, Petr (advisor) ; Červený, Lukáš (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Klára Dohnalová Supervisor: prof. PharmDr. Petr Pávek, Ph.D. Title of diploma thesis: Inhibitory effect of SPA70 on hPXR activation This work focuses on pregnane X receptor (PXR) and its antagonists. PXR is a ligand-activated nuclear receptor that plays a major role in detoxification of xenobiotics and protecting the organism from their toxic effects. Recent evidence also shows endogenous action of PXR in the metabolism of lipids, glucose and bile acids. However, PXR activation could be harmful, since induction of biotransformation enzymes by PXR agonists may result in reduced treatment efficacy, increased toxicity of drug metabolites and resistance to chemotherapeutic agents. Recent research has been intensively focused on PXR antagonists capable of abolishing these unfavourable effects. Recently discovered human PXR antagonist SPA70 has a promising potential for future usage. In this study, we investigated the inhibitory effect of SPA70 on activated PXR. To activate PXR we used agonists binding directly to PXR (rifampicin, hyperforin, SR12813) and also agonists activating PXR indirectly via cell signalling pathways (U0126, PD184352, PD0325901). Experiments were performed using luciferase...
Beneficial Effects of 11β-HSD1 Inhibition on Cognitive Performance in a Mouse Model of Alzheimer's Disease
Červinková, Tereza ; Červený, Lukáš (advisor) ; Musílek, Kamil (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Candidate: Tereza Červinková Supervisor: PharmDr. Lukáš Červený, Ph.D. Title: Beneficial Effects of 11β-HSD1 Inhibition on Cognitive Performance in a Mouse Model of Alzheimer's Disease The increased life expectancy goes hand in hand with ageing-related cognitive impairments. Alzheimer's disease (AD) is the most common type of dementia being an irreversible and progressive brain disorder with loss of cognitive functions. Recent studies suggest that excess of glucocorticoid (GC) action exerts deleterious effects on the hippocampus and causes impaired spatialmemory. In addition, it has been demonstrated that aged mice with cognitive deficits show increased gene expression of 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) in the hippocampus and parietal cortex. The Senescence-Accelerated Mouse Prone 8 (SAMP8) strain is a spontaneous animal model of accelerated ageing. Many studies indicate that SAMP8 harbour the behavioural and histopathological signatures of AD. In the present study, we evaluated the neuroprotective effects of 11β-HSD1 inhibition by a potent pyrrolidine-based compound RL-118 and/or effects of diet on cognitive performance in different groups of SAMP8 by conducting behavioural and...
In vitro transport of abacavir across the monolayer of Caco-2 cells; interaction with etravirine and rilpivirine
Mlčochová, Alice ; Čečková, Martina (advisor) ; Červený, Lukáš (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Pharmacology and Toxicology Student: Alice Mlčochová Supervisor: PharmDr. Martina Čečková, Ph.D. Title of diploma thesis: In vitro transport of abacavir across the monolayer of Caco-2 cells; interaction with etravirine and rilpivirine. Abacavir belongs among nucleoside reverse transciptase inhibitors (NRTIs) representing a basic component of combined antiretroviral therapy used in treatment of HIV-positive patients [1]. Etravirine and rilpivirine are newer non-nucleoside reverse transcriptase inhibitors (NNRTIs) combined in cART together with NRTI. ATP-dependent transporters, so called ABC transporters, are able to affect pharmacokinetic properties of drugs, thus they are important site of drug-drug interactions affecting absorption, distribution and excretion level. P-glycoprotein (Pgp, ABCB1) and BCRP (ABCG2) belong among the most clinically important ABC transporters able to cause drug-drug interactions. The aim of this thesis was to introduce and optimize the method for evaluation of drug absorption using monolayers of Caco-2human intestine cell lines, whose integrity was verified by evaluating TEER (transepithelial electrical resistance). This model was also used for abacavir transport studies. Significant...
Beneficial Effects of 11β-HSD1 Inhibition on Cognitive Performance in a Mouse Model of Alzheimer's Disease
Červinková, Tereza ; Červený, Lukáš (advisor) ; Musílek, Kamil (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Candidate: Tereza Červinková Supervisor: PharmDr. Lukáš Červený, Ph.D. Title: Beneficial Effects of 11β-HSD1 Inhibition on Cognitive Performance in a Mouse Model of Alzheimer's Disease The increased life expectancy goes hand in hand with ageing-related cognitive impairments. Alzheimer's disease (AD) is the most common type of dementia being an irreversible and progressive brain disorder with loss of cognitive functions. Recent studies suggest that excess of glucocorticoid (GC) action exerts deleterious effects on the hippocampus and causes impaired spatialmemory. In addition, it has been demonstrated that aged mice with cognitive deficits show increased gene expression of 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) in the hippocampus and parietal cortex. The Senescence-Accelerated Mouse Prone 8 (SAMP8) strain is a spontaneous animal model of accelerated ageing. Many studies indicate that SAMP8 harbour the behavioural and histopathological signatures of AD. In the present study, we evaluated the neuroprotective effects of 11β-HSD1 inhibition by a potent pyrrolidine-based compound RL-118 and/or effects of diet on cognitive performance in different groups of SAMP8 by conducting behavioural and...

National Repository of Grey Literature : 45 records found   1 - 10nextend  jump to record:
See also: similar author names
3 Červený, Luboš
Interested in being notified about new results for this query?
Subscribe to the RSS feed.