Papers by Ingrid Zitnanová
Zenodo (CERN European Organization for Nuclear Research), May 11, 2023
International Journal of Molecular Sciences
Introduction: Epidemiological studies have suggested an increased vascular risk in patients with ... more Introduction: Epidemiological studies have suggested an increased vascular risk in patients with multiple sclerosis (MS). There is increasing evidence of the beneficial effects of GLP-1 agonists (GLP-1a) in preventing vascular complications and slowing the progression of neurodegeneration. Our objective was to explore the changes in the endothelial function of MS patients after 12 months of GLP-1a therapy. We also explored the role of lipoprotein subfractions and the antioxidant capacity of plasma. Methods: MS patients were enrolled in a prospective, unicentric study. GLP-1a (dulaglutide) was administered to 13 patients. The control population consisted of 12 subjects. Endothelial function was determined by peripheral arterial tonometry and expressed as reperfusion hyperemia index (RHI). Trolox equivalent antioxidant capacity (TEAC) was used to assess the total antioxidant capacity of the plasma. The levels of lipoprotein subfractions were evaluated. Results: The GLP-1a group did no...
ISEE Conference Abstracts, 2020
Physiological Research, 2021
Autonomic nervous system (ANS) disorders are common in multiple sclerosis (MS). Previous studies ... more Autonomic nervous system (ANS) disorders are common in multiple sclerosis (MS). Previous studies showed differences in insulin resistance (IR) and lipoprotein levels in MS subjects compared to controls. Lipolysis caused by increased sympathetic activity could be one of the possible linking mechanisms leading to dyslipidemia in MS. Our study aimed to evaluate ANS activity in the context of glucose and lipid metabolism in people with MS. We prospectively measured short-term heart rate variability (HRV), fasting lipoprotein concentrations, and calculated IR indices based on plasma glucose and insulin levels during oral glucose tolerance test (oGTT) in 32 patients with MS and 29 healthy controls matched for age, sex and body mass index in our study. There was no significant difference in HRV parameters and lipoprotein levels between MS and controls. A significant positive correlation was found between low/high-frequency power ratio (LF/HF) and triglycerides (r=0.413, p=0.021) in MS subj...
Neuro endocrinology letters, 2019
OBJECTIVES To compare two different analytical methods for determination of small dense LDL and t... more OBJECTIVES To compare two different analytical methods for determination of small dense LDL and to determine a share of corresponding and non-corresponding (inconsistent) results METHODS: In the group of 104 hyperlipidemic patients and 20 healthy individuals of the control group we analysed the total cholesterol and triglycerides by enzymatic CHOD PAP method (Roche Diagnostics, Germany) in EDTA-K2 plasma. Small dense LDL (sdLDL) were quantified by the electrophoretic method for lipoprotein analysis on polyacrylamide gel (PAG) (Lipoprint LDL System, Quantimetrix, CA, USA) and simultaneously, the small dense LDL concentrations in the indentical samples were analysed by an enzymatic method LDL-EX ´Seiken´(Randox, England). RESULTS In 31 patients we found the discrepancy in the sdLDL levels using the two different procedures. Out of them, 24 patients tested by enzymatic method ´SEIKEN´ had higher sdLDL values (more than 0.9 mmol/l) compared to the Lipoprint LDL results, which identified...
Neuro endocrinology letters, 2019
OBJECTIVES Multiple sclerosis (MS) is a chronic inflammatory autoimmune and neurodegenerative dis... more OBJECTIVES Multiple sclerosis (MS) is a chronic inflammatory autoimmune and neurodegenerative disease of the central nervous system (CNS) typically affecting young adults. Although the pathogenesis of MS is not fully understood, there is evidence to suggest that inflammation-induced oxidative stress can play a role in demyelination and axonal damage. Oxidative stress also participates in the pathogenesis of endothelial dysfunction and atherogenesis. Data from large epidemiological studies showed a higher risk of vascular events in MS patients. The aim of our study was to analyse the presence of oxidative stress and its association with the parameters of subclinical atherosclerosis in the early stages of MS. MATERIAL AND METHODS We compared 13 newly diagnosed MS patients with a group of 13 healthy age- and BMI-matched controls. Blood samples were measured for total antioxidant activity using TEAC assay. Endothelial function, expressed as reperfusion hyperaemia index (RHI) and arteria...
Molecular and Cellular Biochemistry, 2020
Abstract Senescence is an irreversible permanent cell cycle arrest accompanied by changes in cell... more Abstract Senescence is an irreversible permanent cell cycle arrest accompanied by changes in cell morphology and physiology. Bioactive compounds including tocotrienols (vitamin E) can affect important biological functions. The aim of this study was to investigate how γ- and δ-tocotrienols can affect stress-induced premature senescence. We established two different models of premature stress senescence by induction of senescence with either hydrogen peroxide or etoposide in human lung fibroblasts MRC-5 (ECACC, England). We observed increased percentage of cells with increased SA-β-galactosidase activity, decreased cell viability/proliferation and increased level of p21 in both models. In addition, γ-tocotrienol or δ-tocotrienol (both at concentrations of 150, 200 and 300 μM) were added to the cells along with the inductor of senescence (cotreatment). We have found that this cotreatment led to the decrease of cell viability/proliferation in both models of premature stress senescence, but did not change the percentage of senescent cells. Moreover, we detected no expression of caspase-3 or apoptotic DNA fragmentation in any models of premature stress senescence after the cotreatment with γ- as well as δ-tocotrienols. However, an increased level of autophagic protein LC-3 II was detected in cells with hydrogen peroxide—induced senescence after the cotreatment with γ-tocotrienol as well as δ-tocotrienol. In case of etoposide—induced senescence only δ-tocotrienol cotreatment led to an increased level of LC-3 II protein in cells. According to our work δ-tocotrienol is more effective compound than γ-tocotrienol. Graphic abstract
Journal of Stroke Medicine, 2020
Background: Sleep-disordered breathing (SDB) and hyperlipidemia belong to known stroke risk facto... more Background: Sleep-disordered breathing (SDB) and hyperlipidemia belong to known stroke risk factors. There is an increasing evidence that chronic intermittent hypoxia is independently associated with dyslipidemia. However, the clinical evidence linking SDB with dyslipidemia is poorly described. In this study, we aimed to find possible association between lipoprotein levels and sleep apnea parameters in acute ischemic stroke patients. Methods: 90 patients with acute cerebral ischemia were prospectively enrolled. Blood samples were obtained in a fasting condition within 24 hours after the stroke onset for the analysis of total cholesterol (TC), low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, and triglycerides (TG). SDB was assessed using standard overnight polysomnography. Results: SDB was present in 50%, hypercholesterolemia in 52.2%, and hypertriglyceridemia in 20% of the subjects. In linear regression analysis, apnea–hypopnea index (AHI) was t...
Clinical Biochemistry, 2020
Obesity Research & Clinical Practice, 2019
Stress, 2016
Abstract In an ischemic environment, brain tissue responds to oxygen deprivation with the initiat... more Abstract In an ischemic environment, brain tissue responds to oxygen deprivation with the initiation of rapid changes in bioenergetic metabolism to ensure ion and metabolic homeostasis. At the same time, the accelerated cleavage of membrane phospholipids changes membrane composition and increases free fatty acid concentration. Phospholipid breakdown also generates specific messengers that participate in signaling cascades that can either promote neuronal protection or cause injury. The net impact of signaling events affects the final outcome of the stroke. While reoxygenation is a life-saving intervention, it can exacerbate brain damage. Although compromised energy metabolism is restored shortly after reperfusion, alterations in membrane phospholipid composition with subsequent accumulation of lipid oxoderivates are neurotoxic, causing oxidative stress and ischemia–reperfusion (IR) injury. Thus, plasma and mitochondrial membranes are the first responders as well as mediators of IR-induced stress signals. In this review, we focus on ischemia-induced changes in brain energy metabolism and membrane functions as the causal agents of cell stress responses upon reoxygenation. The first part of the review deals with the specificities of neuronal bioenergetics during IR and their impact on metabolic processes. The second part is concentrated on involvement of both plasma and mitochondrial membranes in the production of messengers which can modulate neuroprotective pathways or participate in oxidative/electrophilic stress responses. Although the etiology of IR injury is multifactorial, deciphering the role of membrane and membrane-associated processes in brain damage will uncover new therapeutic agents with the ability to stabilize neuronal membranes and modulate their responses in favor of prosurvival pathways.
Journal of Organometallic Chemistry, 2017
Scandinavian Journal of Clinical and Laboratory Investigation, 2016
Pharmacological Reports, 2016
Autophagy plays an important role in cancer cells. Targeting autophagy in cancer can provide new ... more Autophagy plays an important role in cancer cells. Targeting autophagy in cancer can provide new opportunities for drug development. In this study we tested four Schiff base Cu(II) complexes against human breast cancer cells (MCF-7) and human non-cancerous cells (HEK-293T). We have tested their cytotoxic effect by evaluating IC using MTT test. To detect morphological changes of the actin fibers we have used fluorescent microscopy. To determine the type of cell death we used electrophoretic analysis and western blot analysis (protein LC3). IC values of the complexes increased with time of their influence, indicating acquired resistance of MCF-7 to the complexes. Healthy cells HEK-293T were not sensitive to the Cu(II) complexes. Compared with the control cells (cells without Cu(II) complexes) which were without morphological changes of actin fibers, Cu(II) complexes induced condensation and asymmetric conformational changes in actin filaments. To examine the type of cell death induced by the Cu(II) complexes we treated MCF-7 cells with Cu(II) complexes (1, 10, 50 and 100μmol/L) during a 72h incubation period. By electrophoresis we have not detected any DNA fragmentation. To determine whether Cu(II) complexes induced autophagy or necrotic cell death we used the western blot analysis. MCF-7 cells influenced with tested Cu(II) complexes produced LC3 protein after their 72h incubation indicating autophagy in MCF-7 cancer cells. Tested Schiff base copper (II) complexes have antiproliferative activity against cancer cells but not against healthy cells. They have induced autophagy in the cancer cell line MCF-7.
Collection Symposium Series, 2005
Proceedings of the National Academy of Sciences, 2004
Corazonin is a highly conserved neuropeptide hormone of wide-spread occurrence in insects yet is ... more Corazonin is a highly conserved neuropeptide hormone of wide-spread occurrence in insects yet is associated with no universally recognized function. After discovery of the corazonin receptor in Drosophila , we identified its ortholog in the moth, Manduca sexta , as a prelude to physiological studies. The corazonin receptor cDNA in M. sexta encodes a protein of 436 amino acids with seven putative transmembrane domains and shares common ancestry with its Drosophila counterpart. The receptor exhibits high sensitivity and selectivity for corazonin when expressed in Xenopus oocytes (EC 50 ≈ 200 pM) or Chinese hamster ovary cells (EC 50 ≈ 75 pM). Northern blot analysis locates the receptor in peripheral endocrine Inka cells, the source of preecdysis- and ecdysis-triggering hormones. Injection of corazonin into pharate larvae elicits release of these peptides from Inka cells, which induce precocious preecdysis and ecdysis behaviors. In vitro exposure of isolated Inka cells to corazonin (25...
Free Radical Research, 2013
Crohn's disease (CD) is a nonspecific, chronic inflammatory disease of the gastrointestin... more Crohn's disease (CD) is a nonspecific, chronic inflammatory disease of the gastrointestinal tract. It is supposed that in etiopathogenesis oxidative stress (OS) plays a role. However, its precise role in the active and non-active states of disease is not known yet. We conducted a pilot study focusing on the relationship between OS of CD in remission and the possibility to influence clinical parameters and markers of OS by polyphenolic extract, Pycnogenol® (Pyc). Compared to 15 healthy controls 15 pediatric CD patients (all were in remission according to their disease activity index - PCDAI) had reduced the activity of Cu/Zn-superoxide dismutase (SOD) and increased the oxidative damage to proteins. We found negative correlations between markers of inflammation (calprotectin, CRP) as well as between PCDAI and total antioxidant capacity (TAC). Activities of antioxidant enzymes, SOD, and glutathione peroxidase (GPX) negatively correlated with calprotectin and PCDAI. Pyc (2 mg/kg) positively influenced the parameters of OS in CD patients after 10 weeks of administration.
Free Radical Biology and Medicine, 2012
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Papers by Ingrid Zitnanová