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Influence of electrical pulses on human blood phagocytes
Chorvátová, Michaela ; Číž,, Milan (referee) ; Kubala,, Lukáš (advisor)
The phagocytic cells circulating in the bloodstream play a key role in both the defense of the body and the pathology of inflammatory diseases. Thus, targeting their functions has potential to modulate an immune response, especially during the inflammatory phase. This master's thesis was focused on the influence of electric pulses on the most abundant phagocyte population in human peripheral blood, namely neutrophils. The theoretical part describes the role of neutrophils in the development of the immune response and the effects of the electric field on various cells. Consequent part of the thesis was the optimization of the electrical stimulation of neutrophils using a unique platform with a network of gold electrodes. In stimulated cells by electrical pulses, activation of selected signaling pathways, degranulation, ROS production, citrullination of histone H3 and expression of surface markers were monitored. Overall, electrical stimulation was observed to induce neutrophil activation but only electrical pulses of size 1 V were found to be statistically significant in the case of ROS production and 10 mV and 100 mV electrical pulses in the case of metalloproteinase MMP8 degranulation. The absence of significant effects in the most observed parameters was probably due to unwanted activation of neutrophils in control samples.
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Regulation of epithelial plasticity by ERK1 and ERK2 isoforms
Rasl, Jan ; Vomastek, Tomáš (advisor) ; Rösel, Daniel (referee) ; Libusová, Lenka (referee)
The ERK pathway is an evolutionarily conserved three-tier signaling cascade comprised of protein kinases Raf, MEK, and ERK. These core kinases are arranged in a hierarchical order and the signal is transduced from Raf to MEK to ERK. The ERK pathway is activated by diverse extracellular signals and in response regulates many cellular processes including cell proliferation, differentiation, apoptosis, migration or epithelial plasticity. Given the role of the ERK pathway in regulating such fundamental cellular processes, the ERK pathway signaling is tightly controlled and its dysregulation has pathological consequences such as cancer development and progression. Although much is known about mechanisms underlying the signal transduction by the ERK signaling pathway, much less is known about how two highly homologous ERK1 and ERK2 isoforms contribute to the signaling by this pathway. In this thesis, I studied isoform-specific functions of ERK1 and ERK2 using epithelial Madin- Darby Canine Kidney (MDCK) cells overexpressing either ERK1 or ERK2. Obtained data show that overexpression of ERK2, but not ERK1, had significant effects on the morphology and functional phenotype of MDCK cells. Both ERK1 and ERK2 expressing cells were able to form cohesive clusters, but the only ERK2 overexpression affected...
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Interactions of selected anticancer drugs of the MAPK/ERK signaling pathway inhibitors group with the ABC drug transporters
Slatinský, Lukáš ; Čečková, Martina (advisor) ; Hofman, Jakub (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Lukáš Slatinský Supervisor: Assoc. prof. PharmDr. Martina Čečková, Ph.D. Title of diploma thesis: Interactions of selected anticancer drugs of the MAPK/ERK signaling pathway inhibitors group with the ABC drug transporters ABCB1 (Pgp, P-glycoprotein) and ABCG2 (BCRP, breast cancer resistance protein) are members of a transmembrane efflux ATP dependent transporter family, so called ATP-binding cassettes (ABC). Physiologicaly they are expressed in the cellular membrane and protect body tissues against potentially toxic xenobiotics including drugs. They represent also one of the tumor defense mechanisms when being able to efflux a wide variety of cytotoxic drugs out of the cancer cells leading to treatment failure. BRAF protein plays an important regulatory and signal role in MAPK/ERK pathway affecting cell division, differentiation and secretion. Mutations of BRAF lead to overactivity in MAPK/ERK pathway in many cancer cells and can be therefore targeted by anticancer therapy. Cobimetinib and dabrafenib are relatively new anticancer therapeutics inhibiting the signal pathway mentioned above and they are used in treatment of melanoma carrying the BRAF mutation. The aims of this project were to...
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The impact of Fam84b in retinal homeostasis
Raishbrook, Miles Joseph ; Procházka, Jan (advisor) ; Mašek, Jan (referee)
Fam84b is a largely unstudied protein, where its function in eukaryotic cells is unclear. This thesis work presents a FAM84B knockout mouse model and characterises the resulting retinal phenotype in detail. FAM84B KO mice were morphologically assessed by optical coherence tomography and histological processing, revealing dynamic changes stemming from the photoreceptor and pigmented epithelial layers. This potent phenotype progresses with age, spreading inwards towards the inner retinal layers, as well as laterally to adjacent retinal regions. Comparative localisation of standard retinal cell markers demonstrates that FAM84B KO retinal layering becomes increasingly disorganised, together with deformation of the retinal macrostructure. Due to this, KO mice experience reducing responses to light, as demonstrated by electroretinography, where overall retinal efficiency falls. Fam84b shows homology to the HRASLS enzyme family, which are capable of attenuating Ras-associated signalling. To investigate whether Fam84b possesses a similar function, the level of phosphorylated and activated downstream Ras effectors were compared between wild type and FAM84B KO mouse retinal lysates. A reduction of pERK1 (pY204) in KO lysates suggests that Fam84b holds some function related to this pathway downstream of Ras....
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Influence of electrical pulses on human blood phagocytes
Chorvátová, Michaela ; Číž,, Milan (referee) ; Kubala,, Lukáš (advisor)
The phagocytic cells circulating in the bloodstream play a key role in both the defense of the body and the pathology of inflammatory diseases. Thus, targeting their functions has potential to modulate an immune response, especially during the inflammatory phase. This master's thesis was focused on the influence of electric pulses on the most abundant phagocyte population in human peripheral blood, namely neutrophils. The theoretical part describes the role of neutrophils in the development of the immune response and the effects of the electric field on various cells. Consequent part of the thesis was the optimization of the electrical stimulation of neutrophils using a unique platform with a network of gold electrodes. In stimulated cells by electrical pulses, activation of selected signaling pathways, degranulation, ROS production, citrullination of histone H3 and expression of surface markers were monitored. Overall, electrical stimulation was observed to induce neutrophil activation but only electrical pulses of size 1 V were found to be statistically significant in the case of ROS production and 10 mV and 100 mV electrical pulses in the case of metalloproteinase MMP8 degranulation. The absence of significant effects in the most observed parameters was probably due to unwanted activation of neutrophils in control samples.
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Interactions of selected anticancer drugs of the MAPK/ERK signaling pathway inhibitors group with the ABC drug transporters
Slatinský, Lukáš ; Čečková, Martina (advisor) ; Hofman, Jakub (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Lukáš Slatinský Supervisor: Assoc. prof. PharmDr. Martina Čečková, Ph.D. Title of diploma thesis: Interactions of selected anticancer drugs of the MAPK/ERK signaling pathway inhibitors group with the ABC drug transporters ABCB1 (Pgp, P-glycoprotein) and ABCG2 (BCRP, breast cancer resistance protein) are members of a transmembrane efflux ATP dependent transporter family, so called ATP-binding cassettes (ABC). Physiologicaly they are expressed in the cellular membrane and protect body tissues against potentially toxic xenobiotics including drugs. They represent also one of the tumor defense mechanisms when being able to efflux a wide variety of cytotoxic drugs out of the cancer cells leading to treatment failure. BRAF protein plays an important regulatory and signal role in MAPK/ERK pathway affecting cell division, differentiation and secretion. Mutations of BRAF lead to overactivity in MAPK/ERK pathway in many cancer cells and can be therefore targeted by anticancer therapy. Cobimetinib and dabrafenib are relatively new anticancer therapeutics inhibiting the signal pathway mentioned above and they are used in treatment of melanoma carrying the BRAF mutation. The aims of this project were to...
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Effect of chronic morphine on cell survival after oxidative stress in the SH-SY5Y neuroblastoma cell line
Moutelíková, Karolína ; Hejnová, Lucie (advisor) ; Musílková, Jana (referee)
Morphine is a natural opioid which is used in medicine due to his potent analgesic and sedative effects. In the forefront of scientific interest is a chronic usage of opioids which can lead to a development of drug addiction. Morphine role in oxidative stress was described in last years. It was revealed its protective potencial by many studies. However, some studies described its pro-oxidative effect. The aim of this study was to determinate effect of chronic morphine on cell survival after oxidative stress caused by H202 analog - tBHP in the SH-SY5Y neuroblastoma cell line. The results verified morphine protective effect against oxidative stress. The highest protective effect of morphine was achieved in a concetration of 10 µM. It was desribed that morphine can induce activation of mu-opioid (MOR) and Toll-like 4 (TLR4) receptors signalling pathway on molecular level. The aim of this thesis was to evaluate the role of MOR a TLR4 in protective effect of morphine against oxidative stress by two methods. Firstly, it was used tests of oxidative stress on cell viability. The obtained results demonstrated majority role of TLR4 and minory role of MOR. Afterwards, we assesed changes in the expression of MOR a TLR4 after chronic morphine by SDS-PAGE electrophoresis. Results of these experiments did not...
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Interactions of selected anticancer drugs of the MAPK/ERK signaling pathway inhibitors group with the ABC drug transporters
Slatinský, Lukáš ; Čečková, Martina (advisor) ; Hofman, Jakub (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Lukáš Slatinský Supervisor: Assoc. prof. PharmDr. Martina Čečková, Ph.D. Title of diploma thesis: Interactions of selected anticancer drugs of the MAPK/ERK signaling pathway inhibitors group with the ABC drug transporters ABCB1 (Pgp, P-glycoprotein) and ABCG2 (BCRP, breast cancer resistance protein) are members of a transmembrane efflux ATP dependent transporter family, so called ATP-binding cassettes (ABC). Physiologicaly they are expressed in the cellular membrane and protect body tissues against potentially toxic xenobiotics including drugs. They represent also one of the tumor defense mechanisms when being able to efflux a wide variety of cytotoxic drugs out of the cancer cells leading to treatment failure. BRAF protein plays an important regulatory and signal role in MAPK/ERK pathway affecting cell division, differentiation and secretion. Mutations of BRAF lead to overactivity in MAPK/ERK pathway in many cancer cells and can be therefore targeted by anticancer therapy. Cobimetinib and dabrafenib are relatively new anticancer therapeutics inhibiting the signal pathway mentioned above and they are used in treatment of melanoma carrying the BRAF mutation. The aims of this project were to...
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The regulation of primary response genes by the ERK signaling pathway
Chvalová, Věra ; Vomastek, Tomáš (advisor) ; Doubravská, Lenka (referee)
The ERK signaling pathway represents an evolutionary conserved mechanism that enables cells to perceive various extracellular signals and convert them to a diverse array of biological outcomes such as proliferation, differentiation, cell cycle control, apoptosis or cell migration. Key components of this pathway are protein kinases Raf, MEK and the effector protein kinase ERK. In addition to its physiological role, continuous activation of the ERK pathway caused by somatic mutations of some of its components or upstream regulators appears to be significant cause of many human tumor diseases. That is why this pathway plays an important role also from the biomedical viewpoint. The multistep changes in gene expression are primarily responsible for these physiological and pathological events. Changes in genes expression are induced by activated kinase ERK that after translocation into the nucleus phosphorylates transcription factors (TFs) whose activation, in turn, leads to transcription of so-called immediate early genes (IEGs), many of which also code for other TFs (e.g. c-Fos, c-Jun or c-Myc). The latter TFs then regulate expression of further genes for structural and signaling proteins. This causes global changes in gene expression and leads to functional reprogramming of the cells. This thesis...
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Interactions of mouse polyomavirus with Toll-like receptors
Pokorná, Karolína ; Forstová, Jitka (advisor) ; Němečková, Šárka (referee)
Toll-like receptors (TLRs) are important receptor family of innate immunity. They enable fast recognition of infection through so called pathogen associated molecular patterns (PAMPs). In this thesis, we studied interaction of mouse polyomavirus (MPyV) with TLRs of mouse embryonic fibroblasts (MEF cells). We observed that inhibition of TLR4 signaling abolished response of MEF cells to MPyV. This suggested that TLR4 plays a role in MEF cells recognition of MPyV. To detect response of MEF cell to MPyV, we measured IL-6 production by ELISA. Next, we investigated effect of TLR4 signalization on MPyV infection. Inhibition of TLR4 signaling with CLI-095 inhibitor did not affect number of infected cells. Presence of TLR4 antagonist, LPS-RS, led to significant decrease in quantity of infected cells 20 hours post infection. Decrease in number of infected cells was also observed in presence of LPS. Viral infection was also inhibited by TLR9 antagonist ODN 2088. We also investigated role of MAP kinases in MPyV infection. We tested, whether inhibition of selected MAP kinases would affect number of infected cells. Inhibition of kinase p38 did not affect infection. On the other hand, inhibition of MEK kinase or JNK resulted in decrease of number of cells infected by MPyV.
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