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Clinical Neuroscience

SEPTEMBER 30, 2020

[Prognostic significance of invasion in glioblastoma]

SZIVÓS László, VIRGA József, HORTOBÁGYI Tibor, ZAHUCZKY Gábor, URAY Iván, JENEI Adrienn, BOGNÁR László, ÁRKOSY Péter, KLEKNER Álmos

[Glioblastoma is the most common malignant CNS tumor, its surgical removal is hindered by the tumors invasive nature, while current anti-tumor therapies show limited effectiveness – mean overall survival is 16-24 months. Some patients show minimal response towards standard oncotherapy, however there are no routinely available prognostic and predictive markers in clinical practice to identify the background of mentioned differences in prognosis. This research aims to identify the prognostic significance of invasion-related extracellular (ECM) components. Patient groups with different prognoses were created (OS: group A <16 months, group B > 16 months), and internationally recognized prognostic markers (IDH1 mutation and MGMT promoter hyper-methylation) were tested in the flash-frozen tumor samples. Furthermore, the mRNA levels of 46 invasion-related ECM molecules were measured. Clinical data of the patients who have been operated on at the University of Debrecen Clinical Center Department of Neurosurgery and treated at the Department of Clinical Oncology showed no significant differences except for survival data (OS and PFS), and reoperation rate. All samples were IDH wild type. MGMT promoter hypermethylation rate showed significant differences (28.6% vs 68.8%). The expressional pattern of the invasion-related ECM molecules, i.e. the invasion spectrum also showed major differences, integrin β2, cadherin-12, FLT4/VEGFR-3 and versican molecules having signficantly different mRNA levels. The accuracy of the inivasion spectrum was tested by statistical classifier, 83.3% of the samples was sorted correctly, PPV was 0.93. The difference found in the reoperation rate when comparing different prognostic groups aligns with literature data. MGMG promoter region methylation data in Hungarian samples has not been published yet, and further confirming current knowledge urges the implementation of MGMT promoter analysis in clinical practice. Studying the invasion spectrum provides extra information on tumors, as a prognostic marker it helps recognizing more aggressive tumors, and calls attention to the necessity of using anti-invasive agents in GBM therapies in the future.]

Hypertension and nephrology

FEBRUARY 20, 2014

[Effect of age on the function of renin-angiotensin system]

VÁMOS Zoltán, CSÉPLÕ Péter, KOLLER Ákos

[Angiotensin II (Ang II) by activating angiotensin type 1 receptors (AT1R) is one of the most potent vasoconstrictors in the regulation of vasomotor tone and thus systemic blood pressure. In this study, we hypothesized that aging alters Ang II - induced vasomotor responses and expression of vascular mRNA and protein angiotensin type 1 receptor (AT1R). Thus, carotid arteries were isolated from newborn, young, middle age, old and senescent rats and their vasomotor responses were measured in a myograph (DMT-600) to repeated administrations of Ang II. Vascular relative AT1R mRNA level was determined by qRT-PCR and the AT1R protein density was measured by Western blot. Contractions of vessels to the first administration of Ang II increased from newborn to young and middle age rats then they decreased to senescent rats. In general, second administration of Ang II elicited reduced contractions, but they also first increased and then they decreased to old age. Similarly, the AT1R mRNA level and the AT1R protein density increased from newborn to young and middle age rats then they decreased to senescent rats. The pattern of these changes correlated with functional vasomotor data. We conclude that aging (newborn to senescence) has substantial effects on Ang II-induced vasomotor responses and AT1R signaling suggesting that it is - and thus regulation of systemic blood pressure is - determined primarily by genetic programs.]

Lege Artis Medicinae

FEBRUARY 22, 2013

[New possibilities in treating hyperlipidemia]

CSÁSZÁR Albert

[In the fight against atherosclerosis, statin therapy is one of the most important elements. On the basis of data from the past few years the clinical introduction of a more effective statin is not expected, however, in order to improve cardiovascular prevention further development of agents that reduce LDL-cholesterol levels more effectively than currently used statins is warranted. The need for the development of new cholesterol-lowering therapeutic options is also supported by the existence of statin intolerance. The currently available combination therapies do not provide additional mortality benefits compared with statin monotherapy. The new solutions include fourth-generation statin molecules that primarily aim to enhance the NO-donor capacity of statins, and to reduce their muscle toxicity. Certain compounds that affect cholesterol synthesis (squalene synthase inhibitors, MTP inhibitors, ACAT inhibitors) need to be further analysed because of the risk of side effects. The use of an antisense oligonucleotid that blocks the mRNA of apoB, the main protein on the LDL-particle and antibodies that inhibit the protein PCSK9 that promotes the intracellular breakdown of the LDL-receptor seems to be much more promising. Besides the lowering of LDLcholesterol level, studies have focused on the benefits of increasing HDL-cholesterol levels. Unfortunately, recently completed analyses show that new forms of the strong HDL-C increasing nicotinic acid have not provided any additional benefit when added to statin therapy. Similarly, the adverse effects associated with the promising CETP inhibitors and the lack of additional benefit when combined with statins question the significance of this drug class. The necessity for an absolute increase of HDL-cholesterol levels needs to be revised on the basis of new data, in other words, the exact role of the HDL particle in atherosclerosis needs to be further investigated.]

Clinical Neuroscience

NOVEMBER 20, 2012

[The role of immobilization stress and sertindole on the expression of APP, MAPK-1 and β-actin genes in rat brain]

KÁLMÁN János, PÁKÁSKI Magdolna, SZŰCS Szabina, KÁLMÁN Sára, FAZEKAS Örsike, SÁNTHA Petra, SZABÓ Gyula, JANKA Zoltán

[Stress, depending on its level and quality, may cause adaptive and maladaptive alterations in brain functioning. As one of its multiple effects, elevated blood cortisol levels decrease the synthesis of the neuroprotective BDNF, thus leading to hippocampal atrophy and synapse loss, and rendering it a possible cause for the Alzheimer’s disease (AD) related neuropathological and cognitive changes. As a result of the stress response, intraneuronal alterations - also affecting the metabolism of β-actin - can develop. These have a role in the regulation of memory formation (LTP), but in pathological conditions (AD) they could lead to the accumulation of Hirano bodies (actin-cofilin rods). According to the dementia treatment guidelines, the behavioural and psychological symptoms of AD can be treated with certain antipsychotics. Therefore, the aim of our study was to examine the effects of sertindole (currently not used in the standard management of AD) on the transcription of some AD associated genes (amyloid precursor protein [APP], mitogen activated protein kinase-1 [MAPK-1], β-actin) in the brain of rats exposed to chronic immobilization stress (CIS). Male Wistar rats were exposed to CIS for three weeks. The four groups were: control (n=16), CIS (n=10), 10 mg/kg sertindole (n=5) and 10 mg/kg sertindole + CIS (n=4). Following transcardial perfusion, the relative levels of hippocampal and cortical mRNA of the previously mentioned genes were measured with real-time PCR. CIS induced hippocampal β-actin (p<0.01), MAPK-1 and APP (p<0.05) mRNA overexpression. The simultaneous administration of sertindole suppressed this increase in β-actin, MAPK-1 and APP expression (p<0.05). Ours is the first report about CIS induced β-actin gene overexpression. This finding, in accordance with the similar results in APP and MAPK-1 expression, underlines the significance of cytoskeletal alterations in AD pathogenesis. The gene expression reducing effect of sertindole suggests that antipsychotic drugs may have a neuroprotective effect.]

Clinical Neuroscience

MAY 30, 2012

[Acute and chronic stress induced changes in gene transcriptions related to Alzheimer’s disease]

SÁNTHA Petra, PÁKÁSKI Magdolna, FAZEKAS Örsike, SZŰCS Szabina, FODOR Eszter Klára, KÁLMÁN János ifj., KÁLMÁN Sára, SZABÓ Gyula, JANKA Zoltán, KÁLMÁN János

[Preclinical and clinical studies demonstrate that stress may be implicated in the risk of neurodegenerative diseases such as Alzheimer’s disease (AD). Our study aimed to investigate the effects of acute and chronic immobilization stress (IS) on the gene transcriptions of β-actin, amyloid precursor protein (APP) and mitogen activated protein kinase-1 (MAPK-1), proteins related to synaptic plasticity and neuronal degeneration. Male Wistar rats were exposed to IS for five hours daily for 3 days (acute stress) or through 7-14-21 days (chronic stress). At the end of exposure periods, total RNA was purified from the cortex and hippocampus. The amounts of β-actin, APP and MAPK-1 mRNA were determined with real time PCR method. Our results indicate that the mRNA expression of β-actin and APP followed a U-shaped time-response curve. Both acute and chronic IS caused a significant increase in β-actin and MAPK-1 mRNA expression. Significant APP mRNA elevation was observed only by the 3rd week after RS. Our findings demonstrate that both acute and chronic IS lead to gene transcriptional changes of β-actin, APP and MAPK-1. These proteins maintain the normal function of the cytoskeleton and the synaptic plasticity. The above changes may lead to cognitive deterioration, and the development of AD.]

Clinical Neuroscience

MARCH 20, 2007

[THE ROLE OF VASOPRESSIN IN CHRONIC STRESS STUDIED IN A CHRONIC MILD STRESS MODEL OF DEPRESSION]

ZELENA Dóra, DOMOKOS Ágnes, BARNA István, CSABAI Katalin, BAGDY György, MAKARA B. Gábor

[Background and purpose - Vasopressin plays an important role in the hypothalamo-pituitary-adrenal axis regulation as well as in stress-related disorders. A common view suggested that the role of vasopressin is especially important during chronic stresses. Here we tested the hypothesis that vasopressin-deficient rats may be more resistant to the development of chronic hypothalamo-pituitary-adrenal axis hyperactivity after chronic mild stress. Methods - Male vasopressin deficient Brattleboro rats were compared to their heterozygous littermattes. Chronic mild stress consisted of different mild stimuli (e.g. wet cages, restraint) for 6 week. The corticosterone changes were followed by repeated tail cutting and organs and blood were collected from decapitated rats. Results - In controls, chronic mild stress resulted in symptoms of chronic stress state characterized by typical somatic (body weight reduction, thymus involution) and endocrine changes (resting plasma ACTH and corticosterone elevation and POMC mRNA elevation in anterior lobe of the pituitary). Unexpectedly, the lack of vasopressin could not influence any chronic mild stress-induced changes. Conclusion - Somatic changes and endocrine effects of chronic mild stress are similar in control and vasopressin deficient animals. This suggests that either vasopressin is not indispensable for activating the hypothalamo-pituitaryadrenal axis by chronic stress or the absence of vasopressin is compensated by other mediators (e.g. CRH) in Brattleboro rats.]

Clinical Neuroscience

JANUARY 20, 2005

[EXPERIMENTAL DEMYELINATION CAUSED BY PRIMARY OLIGODENDROCYTE DYSTROPHY Regional distribution of the lesions in the nervous system of mice brain]

KOMOLY Sámuel

[Background and purpose - Heterogeneity of multiple sclerosis lesions has been recently indicated: In addition to T-cell-mediated or T-cell plus antibody-mediated autoimmune mechanisms (patterns I-II) two other patterns (III-IV) were described. Patterns III-IV are characterized by primary oligodendrocyte dystrophy, reminiscent of virus- or toxin-induced demyelination rather than autoimmunity. It was described more than 30 years ago that dietary application of a copper-chelating agent called cuprizone results in primary oligodendrocyte degeneration which is followed by demyelination. The aim of the present study was to examine the regional distribution of cuprizone induced oligodendrocyte dystrophy and demyelination in the nervous system of mice. Material a methods - Demyelination was induced in male weanling Swis-Webster mice by feeding them on a diet containing 0.6% (W/W) cuprizone bis(cyclohexanone)-oxalyldihydrazone (G. F. Smith Chemical, Columbus OH) for 8 weeks. Animals were sacrificed after 3, 7, 14, 27, 35, 56 days of cuprizone administration. Samples were taken from corpus callosum, anterior commissure, optic nerve, cervical spinal cord and sciatic nerve. Samples were examined by immunohistochemistry, in situ hybridization for myelin proteins and myelin protein mRNA-s, respectively. Conventional neuropathological stainings and electron microscopy was also performed. Results - Oligodendrocyte degeneration and demyelination followed a particular standard pattern in the central nervous system. Profound myelin loss developed in the superior cerebellar peduncle, anterior comissure and corpus callosum, whereas the optic nerves, velum medullare anterior and spinal cord showed little or no demyelination. Sciatic nerves were unaffected. No infiltration by lymphocytes or blood-brain barrier damage was observed during cuprizone treatment. Conclusion - Cuprizone induced oligodendrocyte damage and demyelination follows a particular standard pattern in the central nervous system of mice. Cuprizone induced demyelination might be considered as a model for human demyelinating disorders with primary oligodendrocyte dystrophy and apoptosis.]

Clinical Neuroscience

JANUARY 30, 2010

[Extracellular matrix of intracerebral tumors with different invasion activity]

KLEKNER Álmos, VARGA Imre, BOGNÁR László, HUTÓCZKI Gábor, KENYERES Annamária, TÓTH Judit, HANZÉLY Zoltán, SCHOLTZ Beáta

[Objectives - Ineffective surgical and radiotherapy of glioblastoma is mainly due to its intensive infiltrating behavior. Contrarily, brain metastases of anaplastic carcinomas are well-circumscribed intracerebral lesions that can be easily exstirpated in most cases. The molecules of the extracellular matrix (ECM) play a pivotal role in the peritumoral infiltration. In this study the mRNA expression of the ECM components was investigated in two types of intracerebral malignoma with different invasion activity. Our aim was to identify the ECM molecules that are responsible for the different intensity of peritumoral infiltration of tumors from different origin. Methods - The mRNA expression of twenty-three ECM molecules was determined by quantitative reverse transcriptase polymerase chain reaction. Four pieces of glioblastoma and four pieces of intracerebral lung adenocarcinoma metastasis from neurosurgical operation were investigated. Immunohistochemical investigations were performed in case of five molecules. Results - The mRNA expression of nine molecules (brevican, neurocan, neuroglycan-C, syndecan-1,2,4, tenascin-C, versican and matrix-metalloproteinase-[MMP]2) differed significantly by comparison of the two tumor types. By immunohistochemistry, neurocan, syndecan, versican and MMP-2 showed alteration in staining intensity according to the mRNA expression, while MMP-9 showed higher staining intensity in the metastatic tumor. Conclusions - The identified molecules can play an important role in the different infiltration activity of tumors from different origin. Thus these ECM-components could serve as targets for anti-invasion therapy in the future.]

Clinical Neuroscience

MARCH 30, 2008

[Evidence for the expression of parathyroid hormone 2 receptor in the human brainstem (in English language)]

BAGÓ G. Attila, PALKOVITS Miklós, USDIN B. Ted, SERESS László, DOBOLYI Árpád

[Background and purpose - The parathyroid hormone 2 receptor (PTH2R) is a G protein coupled receptor. Pharmacological and anatomical evidence suggests that the recently identified tuberoinfundibular peptide of 39 residues is, and parathyroid hormone and parathyroid hormone-related peptide are not, its endogenous ligand. Initial functional studies suggest that the PTH2R is involved in the regulation of viscerosensory information processing. As a first step towards clinical applications, herein we describe the presence of the PTH2R in the human brainstem. Material and methods - Total RNA was isolated from postmortem human cortical and brainstem samples for RT-PCR. Good quality RNA, as assessed on formaldehyde gel, was reverse transcribed. The combined cDNA products were used as template in PCR reactions with primer pairs specific for the human PTH2R. In addition, PTH2R immunolabelling was performed on free floating sections of the human medulla oblongata using fluorescent amplification immunochemistry. Results - Specific bands in the RT-PCR experiments and sequencing of PCR products demonstrated the expression of PTH2R mRNA in the human brainstem. A high density of PTH2R-immunoreactive fibers was found in brain regions of the medulla oblongata including the nucleus of the solitary tract, the spinal trigeminal nucleus, and the dorsal reticular nucleus of the medulla. Conclusion - Independent demonstration of the presence of PTH2R mRNA and immunoreactivity supports the specific expression of the PTH2R in the human brainstem. The distribution of PTH2R-immunoreactive fibers in viscerosensory brain regions is similar to that reported in mouse and rat suggesting a similar role of the PTH2R in human as in rodents. This finding will have important implications when experimental data obtained on the function of the TIP39-PTH2R neuromodulator system in rodents are to be utilized in human.]

Lege Artis Medicinae

OCTOBER 20, 2010

[Postmenopausal changes of immune system-related genes expression in human bone tissue]

BALLA Bernadett, KÓSA P. János, KISS János, PODANI János, TAKÁCS István, LAZÁRY Áron, BÁCSI Krisztián, NAGY Zoltán Zsolt, SPEER Gábor, LAKATOS Péter

[INTRODUCTION - The molecular and cellular interactions between the immune system and bone tissue have been established. Sex hormone deficiency at the time of menopause has multifunctional role by influencing growth, differentiation and metabolism of the skeletal and the immune system. We have used non-parametric and multidimensional expression pattern analyses to determine significantly changed mRNA profile of immune system-associated genes in postmenopausal (POST) and premenopausal (PRE) non-osteoporotic bone. MATERIALS AND METHODS - Ten bone tissue samples from POST patients and six bone tissue samples from PRE women were examined in our study. The transcription differences of selected 50 genes were analyzed in Taqman probe-based quantitative real-time RT-PCR system. RESULTS - Mann-Whitney test indicated significantly down-regulated transcription activity of 3 genes (CD14, HLA-A, ITGAM/CD11b) and upregulated gene expression of 6 genes (C3, CD86, IL-10, IL-6, TGFB3, TNFSF11/RANKL) in POST bone. According to the canonical variates analysis results, the groups of postmenopausal and premenopausal women are separable by genes coding for cytokines, co-stimulators and cell surface receptors affected in antigen presentation and T cell stimulation which have high discriminatory power. CONCLUSIONS - Based on a complex gene expression patterns in human bone cells, we could distinguish POST and PRE states from an immunological aspect. Our data might provide further insight into the changes of the intersystem crosstalk between immune and skeletal system, as well as local immune response in the altered microenvironment of POST bone.]