National Repository of Grey Literature 20 records found  1 - 10next  jump to record: Search took 0.00 seconds. 
Studies on the molecular mechanisms of cardioprotective effects of morphine
Škrabalová, Jitka ; Novotný, Jiří (advisor) ; Nováková, Olga (referee) ; Hlaváčková, Markéta (referee)
Acute and chronic morphine administration can significantly reduce ischemia- reperfusion injury of the rat heart. However, the molecular mechanisms mediating the protective effect of morphine are not yet fully elucidated. Concurrently, there is a lack of information about the effects of the long-term action of morphine on heart tissue. Therefore, in the first part of the project, we studied the effect of long-term administration of high doses of morphine (10 mg/kg/day, 10 days) on rat heart tissue. In the second part of the project, we investigated the effect of 1 mM morphine on viability and redox state of rat cardiomyoblast cell line H9c2 that was influenced by oxidative stress elicited by exposure to 300 μM tert-butyl hydroperoxide (t-BHP). Our experiments have shown that long-term morphine administration affected neither the amount nor the affinity of myocardial β-adrenergic receptors (β-AR), but almost doubled the number of the dominant isoforms of myocardial adenylyl cyclase (AC) V/VI and led to supersensitization of AC. At the same time, proteomic analyses revealed that long-term morphine administration was associated with significant changes in the left ventricular proteome. In particular, there was an increase in the expression of heat shock proteins (HSP). Increased expression of HSP27...
Role of protein kinase C isoforms in cardioprotective mechanism of chronic hypoxia
Hlaváčková, Markéta
Cardiovascular diseases, particularly acute myocardial infarction, are one of the leading causes of death in developed countries. It is well known that adaptation to chronic intermittent hypobaric hypoxia (IHH) confers long-lasting cardiac protection against acute ischemia/reperfusion injury. Protein kinase C (PKC) appears to play a role in its cardioprotective mechanism since the administration of general PKC inhibitor completely abolished the improvement of ischemic tolerance in IHH hearts. However, the involvement of individual PKC isoforms remains unclear. Therefore, the primary aim of this study was to investigate the potential involvement of PKCδ and PKCε, the most prevalent PKC isoforms in rat heart, in the mechanism of IHH-induced cardioprotection. We showed that IHH up- regulated PKC protein in left ventricle, enhanced its phosphorylation on Ser643 and increased its co-localization with markers of mitochondrial and sarcolemmal membranes. PKCδ subcellular redistribution induced by IHH as well as the infarct size-limiting effect of IHH was reversed by acute treatment with PKCδ inhibitor rottlerin. These data support the view that PKCδ plays a significant role in IHH-induced cardioprotection. On the other hand, adaptation to IHH decreased the PKC total protein level without affecting its...
Modulation of RNA demethylase FTO function in SH-SY5Y cells: the effect on insulin signaling and mitochondrial respiration
Čočková, Zuzana ; Novotný, Jiří (advisor) ; Hlaváčková, Markéta (referee)
Aim of this thesis was to observe changes in oxidative metabolism and expression of important neuroenergetic proteins in human neuroblastoma cell line SH-SY5Y due to inhibition of FTO. FTO is a RNA demethylase that uses N6-methyladenosine as substrate. Differences in enzyme expression are connected to broad area of effects involving energy homeostasis. Mitochondria are cellular powerhouses, a key elements in production of energy and metabolic substrates, yet a source of potentially dangerous reactive oxygen species (ROS) and analogous reactive molecules. In order to better understand FTO purpose in neuronal energetic metabolism, we examined mitochondrial respiratory chain. Using high-resolution respirometry we were capable of observing impairment in mitochondrial respiration after FTO inhibition. There was considerable decline in endogenous respiration, maximal respiration rate and reserve capacity. In order to obtain more detailed view into mitochondrial respiration, expression levels of electron-transport complexes were quantified by Western blot technique. Slight reduction was identified in subunits of complex I and IV. However, the most prominent alteration was seen in complex II subunit. There were no differences in expression of complex III and ATP synthase subunits. Beside disrupted activity...
The role of RNA-demethylase FTO in the regulation of cellular function and energy homeostasis
Pohanová, Petra ; Telenský, Petr (advisor) ; Hlaváčková, Markéta (referee)
Metyladenosin je nejčastější transkripční RNA. Nedávno bylo zjištěno, že modifikace může významným způsobem ovlivňovat další zpracování, transport a degradaci RNA a celkově je významným epigenetickým regulačním činitelem. demetylázu FTO, jejíž funkce se projevuje významnou regulační funkci v řízení metabolismu a udržování energetické homeostáze. demetylázy FTO může být příčinou různých patofyziologických stavů např. obezit
The role of demethylase FTO and adipokines in the heart: effect of chronic hypoxia
Benák, Daniel ; Hlaváčková, Markéta (advisor) ; Bardová, Kristina (referee)
Adaptace na chronickou hypoxii zvyšuje toleranci srdce k ischemicko-reperfuznímu poškození. Tato adaptace je umožněna řadou fyziologických změn na buněčné úrovni. Jednou z nich je změna v buněčném energetickém metabolismu. Tento proces může být regulován proteinem FTO (z angl. fat mass and obesity associated), demetylázou epigeneticky regulující buněčnou syntézu proteinů. Srdeční metabolismus může být také modulován adipokiny leptinem a adiponektinem. Cílem tohoto projektu bylo proto studovat roli FTO a adipokinů v chronicky hypoxickém srdci. Dospělí samci potkanů kmene Sprague Dawley byli adaptováni na dva modely kontinuální normobarické hypoxie (CNH; 12 % O2 a 10 % O2; 3 týdny). CNH (10 % O2) redukovala u těchto zvířat rozsah infarktu myokardu o 20 %. CNH (12 % O2) nebyla kardioprotektivní. Hladina proteinu FTO byla měřena v tkáni levých (LV) a pravých (RV) komor, stejně jako v játrech a koncovém mozku hypoxických i normoxických zvířat. Za normoxie je hladina FTO v RV o 50 % vyšší než v LV. Ve vysoce metabolicky aktivních tkáních jater a koncového mozku jsou pak hladiny FTO vyšší dokonce 6krát a 11krát. CNH (12 % O2) vedla k signifikantnímu nárůstu hladiny proteinu FTO v srdci. Jednalo se o 21% nárůst v LV a 27% v RV. Hladiny v játrech a koncových mozcích nebyly CNH ovlivněny. Silnější CNH (10 % O2)...
Adipose tissue functional changes during postnatal development and impact of high-fat diet feeding on adipose and liver tissue
Hájková, Simona ; Bardová, Kristina (advisor) ; Hlaváčková, Markéta (referee)
Caloric intake increased over a long period of time may induce the development of obesity, causing so-called low-grade inflammation. The organism responses to the inflammation by the activation and production of cellular components of the immune system, such as macrophages or proinflammatory cytokines. The adipose tissue itself is involved in the production of bioactive molecules, including leptin and adiponectin. Increased concentration of proinflammatory cytokines can lead to a dysfunction of important metabolic pathways and impair organ's function. For the purpose of closer knowledge of the etiology of obesity and its metabolic complications, inbred strains of mice with different genetic backround are most commonly used. We aimed to define the impact of high-fat diet (HFD) on adipose and liver tissue of C57BL/6J and A/J murine strains with a different susceptibility to diet-induced obesity. We focused on description of morphological and functional changes of adipose tissue and on the evaluation of plasma leptin and adiponectin levels of mice in the early postnatal development. Next, we measured the expression of leptin mRNA in four tissues. In this study we described how the increased caloric intake leads to increased triacylglycerides (TAG) storage in the liver and to a higher inflammatory...
Dysregulation of the endocannabinoid system in obesity and its modulation by dietary omega-3 fatty acids
Kalendová, Veronika ; Rossmeisl, Martin (advisor) ; Hlaváčková, Markéta (referee)
Obesity is associated with metabolic complications including insulin resistance, dyslipidemia and hypertension (metabolic syndrome). The endocannabinoid system (ECS) activity is elevated in obesity, which can further potentiate metabolic impairments. Pharmacological treatment based on the cannabinoid receptor CB1 blockade led to a decrease in body weight and significant improvements of metabolic parameters in obese individuals. However, parallel effects on the central nervous system resulted in unwanted side-effects including anxiety and depressive moods. Recent experimental studies suggested that dietary interventions with omega-3 polyunsaturated fatty acids of marine origin (EPA, DHA) can decrease the ECS activity in peripheral tissues (adipose, liver, pancreas), and thus partially protect against metabolic disturbances in obesity. One of the underlying mechanisms behind the effects of EPA and DHA could be a replacement of arachidonic acid from the sn-2 position of membrane phospholipids, thereby reducing the substrate availability for the synthesis of endocannabinoid molecules. Key words: omega-3 fatty acids, obesity, endocannabinoid system, 2-arachidonoylglycerol, anandamide
The role of protein kinase C and its targets in cardioprotection
Holzerová, Kristýna ; Hlaváčková, Markéta (advisor) ; Alán, Lukáš (referee) ; Vízek, Martin (referee)
The mortality of cardiovascular diseases remains high and it likely tends to increase in the future. Although many ways how to increase the resistance against myocardial ischemia- reperfusion damage have been described, few of them were transferred into clinical practice. Cardioprotective effect of chronic hypoxia has been described during 60s of the last century. Its detailed mechanism has not been elucidated, but a number of components has been identified. One of these components presents protein kinase C (PKC). The role of PKC was described in detail in the mechanism of ischemic preconditioning, but its involvement in the mechanism of cardioprotection induced by chronic hypoxia remains unclear. One reason is the amount of PKC isoforms, which have often contradictory effects, and the diversity of hypoxic models used. The most frequently mentioned isoforms in connection with cardioprotection are PKCδ and PKCε. The aim of my thesis was to analyze changes in these PKC isoforms at two different cardioprotective models of hypoxia - intermittent hypobaric (IHH) and continuous normobaric hypoxia (CNH). We also examined the target proteins of PKCδ and PKCε after the adaptation to IHH, which could be involved in the mechanism of cardioprotection. These included proteins associated with apoptosis and...
Adenosine receptors and transporters in rat myocardium: the effect of adaptation to chronic hypoxia
Neumannová, Kateřina ; Novotný, Jiří (advisor) ; Hlaváčková, Markéta (referee)
2. Abstract Adaptation to chronic hypoxia is in addition to ischemic preconditioning one of the two known cardioprotective mechanisms. The precise molecular basis of these processes is still not fully explained. There are some studies that suggest the possible involvement of the adenosinergic signaling system in this adaptation. In this work, we focused on the characterization of the adenosinergic system in the myocardium of rats adapted to two regimens of chronic hypoxia - a protective continuous normobaric hypoxia (CNH) and non-protective intermittent hypoxia (INH/R, 23 h hypoxia and 1 h normoxia). Initially, we compared the total amount of adenosine receptors in samples from different groups of adapted animals. We discovered changes mainly at A2B receptor, which increased at CNH and declined in INH/R. This result suggests the possible involvement of A2B receptors in cardioprotection afforded by adaptation to chronic hypoxia. Furthermore, we investigated the distribution of various types of adenosine receptors and transporters in the plasma membrane of cardiac cells. We observed that A2A and A3 localize in membrane microdomains together with membrane enzyme CD73 that produces adenosine in the extracellular space by degrading AMP. A1 and A2B receptors similarly as nucleoside transporters ENT1, ENT2 and...

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See also: similar author names
2 HLAVÁČKOVÁ, Michaela
1 Hlaváčková, M.
1 Hlaváčková, Marcela
6 Hlaváčková, Marie
5 Hlaváčková, Martina
2 Hlaváčková, Michaela
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