Institute of Medical Biochemistry

Laboratory, Czech Republic

Institute of Medical Biochemistry

Laboratory, Czech Republic
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Milic R.,University of Ljubljana | Martinovic J.,Belgrade Clinical Center | Dopsaj M.,University of Belgrade | Dopsaj V.,University of Belgrade | Dopsaj V.,Institute of Medical Biochemistry
European Journal of Applied Physiology | Year: 2011

We investigated the iron-related haematological parameters in both male and female athletes participating in different sporting disciplines necessitating different metabolic energy demands. A total of 873 athletes (514 males, mean age: 22.08 ± 4.95 years and 359 females, mean age: 21.38 ± 3.88 years) were divided according to gender and to the predominant energy system required for participation in sport (aerobic, anaerobic or mixed) and haematological and iron-related parameters were measured. For both male and female athletes, significant differences related to the predominant energy system were found at a general level: male (Wilks' λ = 0.798, F = 3.047, p < 0.001) and female (Wilks' λ = 0.762, F = 2.591, p < 0.001). According to the ferritin cutoff value of 35 μg/L, whole body iron and sTfR significantly differed in all three groups of male and female athletes (p < 0.001). The percentage of hypochromic erythrocytes in male athletes was significantly higher only in those who required an anaerobic energy source (p < 0.001), whilst in the females hypochromic erythrocytes (p < 0.001) and haemoglobin (anaerobic, p = 0.042; mixed, p = 0.006) were significantly different only in anaerobic and mixed energy source athletes. According to the ferritin cutoff value of 22 μg/L, in females, whole body iron, sTfR and hypochromic erythrocytes were significantly higher in all three groups of athletes than those below the aforementioned cutoff value (p < 0.001). We conclude that the predominant energy system required for participation in sport affects haematological parameters. sTfR and body iron proved to be reliable parameters for monitoring the dynamics of iron metabolism and could contribute to successful iron-deficiency prevention. © 2010 Springer-Verlag.

Hollmann M.,Institute of Animal Nutrition and Functional Plant Compounds | Miller I.,Institute of Medical Biochemistry | Hummel K.,VetCore Facility for Research | Sabitzer S.,VetCore Facility for Research | And 2 more authors.
PLoS ONE | Year: 2013

Energy-rich diets can challenge metabolic and protective functions of the rumen epithelial cells, but the underlying factors are unclear. This study sought to evaluate proteomic changes of the rumen epithelium in goats fed a low, medium, or high energy diet. Expression of protein changes were compared by two-dimensional differential gel electrophoresis followed by protein identification with matrix assisted laser desorption ionisation tandem time-of-flight mass spectrometry. Of about 2,000 spots commonly detected in all gels, 64 spots were significantly regulated, which were traced back to 24 unique proteins. Interestingly, the expression profiles of several chaperone proteins with important cellular protective functions such as heat shock cognate 71 kDa protein, peroxiredoxin-6, serpin H1, protein disulfide-isomerase, and selenium-binding protein were collectively downregulated in response to high dietary energy supply. Similar regulation patterns were obtained for some other proteins involved in transport or metabolic functions. In contrast, metabolic enzymes like retinal dehydrogenase 1 and ATP synthase subunit beta, mitochondrial precursor were upregulated in response to high energy diet. Lower expressions of chaperone proteins in the rumen epithelial cells in response to high energy supply may suggest that these cells were less protected against the potentially harmful rumen toxic compounds, which might have consequences for rumen and systemic health. Our findings also suggest that energy-rich diets and the resulting acidotic insult may render rumen epithelial cells more vulnerable to cellular damage by attenuating their cell defense system, hence facilitating the impairment of rumen barrier function, typically observed in energy-rich fed ruminants. © 2013 Hollmann et al.

Dopsaj V.,Institute of Medical Biochemistry | Dopsaj V.,University of Belgrade | Martinovic J.,Belgrade Clinical Center | Stevuljevic J.K.,University of Belgrade | Bogavac-Stanojevic N.,University of Belgrade
International Journal of Sports Medicine | Year: 2011

The aim of the present study was to examine the association of proteins that regulate iron transport/storage content and acute phase response with oxidative stress in male and female athletes. Serum ferritin, transferrin, soluble transferrin receptor, C-reactive protein, interleukin-6 and oxidative stress parameters (reactive oxygen metabolites, superoxide anion, advanced oxidation protein products, lipid hydroperoxides, superoxide-dismutase and pro-oxidant-antioxidant balance) were determined in 138 athletes (73 females and 65 males). A general linear model indicated significant gender differences between athletes in terms of reactive oxygen metabolites (307.48±61.02 vs. 276.98±50.08; P=0.030), superoxide-dismutase (114.60±41.64 vs. 101.42±38.76; P=0.001), lipid hydroperoxides (149.84±38.95 vs. 101.43±39.26; P<0.001), pro-oxidant-antioxidant balance (512.40±148.67 vs. 413.09±120.30; P=0.002), advanced oxidation protein products (1.49±0.30 vs. 0.91±0.25; P<0.001) and superoxide (2.61±0.36 vs. 2.22±0.35; P=0.001), which were all significantly higher in females. Multivariate analysis of covariance indicated gender (P<0.001), training experience (P=0.004), C-reactive protein (P=0.002), soluble transferrin receptor (P=0.004) and transferrin (P<0.001) as significant covariates. Gender accounted for the largest proportion of variability for all oxidative stress parameters (46.3%) and female athletes were more susceptible to oxidative stress. Iron transport and storage proteins (transferrin and ferritin), but also acute phase reactants, were negatively related factors for oxidative stress. In conclusion, variation in the ferritin level may contribute to the different oxidative stress level between the sexes. © Georg Thieme Verlag KG Stuttgart middot; New York.

Colak E.,Institute of Medical Biochemistry | Kosanovic-Jakovic N.,University of Belgrade | Zoric L.,University of Belgrade | Radosavljevic A.,University of Belgrade | And 2 more authors.
Ophthalmic Research | Year: 2011

Background: Age-related macular degeneration (AMD) is the most common cause of visual impairment in individuals over 50 years of age, with the prevalence of 0.05% before the age of 50 rising to 30% after 74 years of age. An elevated concentration of plasma lipoproteins is considered to be one of the risk factors of AMD development. The aim of our study was to analyze the concentration of serum lipoproteins - total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), non-LDL cholesterol and triglycerides - as well as apolipoproteins - apoA1, apoB and Lp(a) - along with C-reactive protein (CRP) in patients with AMD in order to explore the possible association of lipid and inflammatory parameters with the pathogenesis of AMD. Material and Methods: In the cross-sectional study in the University clinical setting, 79 patients with AMD, aged 71.47 ± 7.02 years, and 84 aged-matched control subjects were included. The patients underwent complete ophthalmological examination including visual acuity assessment, color fundus photography and fluorescein angiography. Results: Statistical processing data revealed significantly higher total (p = 0.0002), LDL (p = 0.023), non-HDL cholesterol (p = 0.0014) and CRP (p = 0.049) values in AMD patients compared to control subjects. Conclusions: Based on the obtained results, it may be concluded that lipid status disorder and inflammation could play an important role in the development of AMD in elderly people. Copyright © 2011 S. Karger AG, Basel.

Martinovic J.,University of Belgrade | Dopsaj V.,University of Belgrade | Dopsaj V.,Institute of Medical Biochemistry | Kotur-Stevuljevic J.,University of Belgrade | And 4 more authors.
Journal of Strength and Conditioning Research | Year: 2011

The objectives of this study were to determine (a) if reactive oxygen metabolites (ROMs) are a reliable parameter for monitoring oxidative stress in athletes alone or in association with other parameters of oxidative stress and depending on whether antioxidant supplements are taken or not; (b) the level of oxidative stress in athletes before the competition season; and (c) if oxidative status could be improved in volleyball athletes. Sixteen women athletes (supplemented group) received an antioxidant cocktail containing vitamin E, vitamin C, zinc gluconate, and selenium as a dietary supplement during a 6-week training period, whereas 12 of them (control group) received no dietary supplement. Blood samples were taken before and after the training period. The following parameters were measured: ROMs, superoxide anion (O- 2), malondialdehyde (MDA), advanced oxidation protein products (AOPP), lipid hydroperoxide (LOOH), biological antioxidative potential (BAP), paraoxonase activity toward paraoxon (POase) and diazoxon (DZOase), superoxide dismutase(SOD), total sulfydryl group concentration (SH groups), and lipid status. Reactive oxygen metabolites were taken as the dependent variable and MDA, O- 2, AOPP, and LOOH as independent variables. In the group of athletes who have received supplementation, linear regression analysis revealed that the implemented model had a lower influence on dROMs (70.4 vs. 27.9%) after the training period. The general linear model showed significant differences between parameters before and after training/supplementation (Wilks' lambda = 0.074, F = 11.76, p < 0.01). At the partial level, significant increases in ROM levels (p,0.05, 95% confidence interval [CI]: 286-337), SOD activity (CI: 113-144), and BAP (CI: 2,388-2,580) (p < 0.01) were observed. The association between ROMs and other parameters of oxidative stress was reduced in athletes who received supplements. During the precompetition training period, treatment with dietary supplements prevented the depletion of antioxidative defense in volleyball athletes. © 2011 National Strength and Conditioning Association.

Brito-Moreira J.,Institute of Medical Biochemistry | Paula-Lima A.C.,Institute of Medical Biochemistry | Paula-Lima A.C.,University of Chile | Bomfim T.R.,Institute of Medical Biochemistry | And 7 more authors.
Current Alzheimer Research | Year: 2011

Soluble oligomers of the amyloid-β peptide (AβOs) accumulate in Alzheimer's disease (AD) brain and have been implicated in mechanisms of pathogenesis. The neurotoxicity of AβOs appears to be, at least in part, due to dysregu-lation of glutamate signaling. Here, we show that AβOs promote extracellular accumulation of glutamate and D-serine, a co-agonist at glutamate receptors of the N-methyl-D-aspartate subtype (NMDARs), in hippocampal neuronal cultures. The increase in extracellular glutamate levels induced by AβOs was blocked by the sodium channel blocker tetrodotoxin (TTX), by the NMDAR blocker (+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine maleate (MK-801) and by removal of Ca + from the extracellular medium, indicating dependence on excitatory neuronal activity. AβOs enhanced the release of pre-synaptic vesicles labeled by FM1-43 as well as spontaneous post-synaptic activity measured by whole-cell patch-clamp. Activation of inhibitory GABA A receptors by taurine blocked the increase in extracellular glutamate levels, suggesting that selective pharmacological inhibition of neuronal activity can counteract the impact of ApOs on glutamate dyshomeostasis. Results reveal a novel mechanism by which Ap oligomers promote abnormal release of glutamate from hippocampal neurons, which may contribute to dysregulation of excitatory signaling in the brain. © 2011 Bentham Science Publishers Ltd.

Fabritz L.,University of Munster | Hoogendijk M.G.,University of Amsterdam | Scicluna B.P.,University of Amsterdam | Van Amersfoorth S.C.M.,University of Amsterdam | And 17 more authors.
Journal of the American College of Cardiology | Year: 2011

Objectives We used a murine model of arrhythmogenic right ventricular cardiomyopathy (ARVC) to test whether reducing ventricular load prevents or slows development of this cardiomyopathy. Background At present, no therapy exists to slow progression of ARVC. Genetically conferred dysfunction of the mechanical cellcell connections, often associated with reduced expression of plakoglobin, is thought to cause ARVC. Methods Littermate pairs of heterozygous plakoglobin-deficient mice (plako+/) and wild-type (WT) littermates underwent 7 weeks of endurance training (daily swimming). Mice were randomized to blinded load-reducing therapy (furosemide and nitrates) or placebo. Results Therapy prevented training-induced right ventricular (RV) enlargement in plako+/ mice (RV volume: untreated plako+/ 136 ± 5 μl; treated plako+/ 78 ± 5 μl; WT 81 ± 5 μl; p < 0.01 for untreated vs. WT and untreated vs. treated; mean ± SEM). In isolated, Langendorff-perfused hearts, ventricular tachycardias (VTs) were more often induced in untreated plako+/ hearts (15 of 25), than in treated plako+/ hearts (5 of 19) or in WT hearts (6 of 21, both p < 0.05). Epicardial mapping of the RV identified macrore-entry as the mechanism of ventricular tachycardia. The RV longitudinal conduction velocity was reduced in untreated but not in treated plako+/ mice (p < 0.01 for untreated vs. WT and untreated vs. treated). Myocardial concentration of phosphorylated connexin43 was lower in plako+/ hearts with VTs compared with hearts without VTs and was reduced in untreated plako+/ compared with WT (both p < 0.05). Plako+/ hearts showed reduced myocardial plakoglobin concentration, whereas β-catenin and N-cadherin concentration was not changed. Conclusions Load-reducing therapy prevents training-induced development of ARVC in plako+/ mice. © 2011 American College of Cardiology Foundation.

Ghavampour S.,Institute of Medical Biochemistry | Lange C.,Institute of Medical Biochemistry | Bottino C.,Instituto Giannina Gaslini | Gerke V.,Institute of Medical Biochemistry
PLoS ONE | Year: 2013

Local inflammatory responses are characterized by the recruitment of circulating leukocytes from the blood to sites of inflammation, a process requiring the directed migration of leukocytes across the vessel wall and hence a penetration of the endothelial lining. To identify underlying signalling events and novel factors involved in these processes we screened for genes differentially expressed in human monocytes following their adhesion to and passage through an endothelial monolayer. Functional annotation clustering of the genes identified revealed an overrepresentation of those associated with inflammation/immune response, in particular early monocyte to macrophage differentiation. Among the gene products so far not implicated in monocyte transendothelial migration was the inhibitory immune receptor CD300a. CD300a mRNA and protein levels were upregulated following transmigration and engagement of the receptor by anti-CD300a antibodies markedly reduced monocyte transendothelial migration. In contrast, siRNA mediated downregulation of CD300a in human monocytes increased their rate of migration. CD300a colocalized and cosedimented with actin filaments and, when activated, caused F-actin cytoskeleton alterations. Thus, monocyte transendothelial migration is accompanied by an elevation of CD300a which serves an inhibitory function possibly required for termination of the actual transmigration. © 2013 Ghavampour et al.

Rogenhofer N.,Ludwig Maximilians University of Munich | Engels L.,Ludwig Maximilians University of Munich | Bogdanova N.,Institute of Human Genetics | Tuttelmann F.,Institute of Human Genetics | And 2 more authors.
Metabolism: Clinical and Experimental | Year: 2013

Objective The aim of this study was to analyze the contribution of the M2 haplotype of ANXA5 gene, previously identified as a risk factor for RPL and thrombophilia related pregnancy complications, to repeated miscarriage observed in PCOS patients. Patients/Methods 100 PCOS patients, 500 fertile women and 533 random population controls were genotyped for M2/ANXA5. Results M2 haplotype carriers faced a 3.4 fold elevated RPL risk (odds ratio 5.3, 95% confidence interval 3-9.2) compared to female fertile controls and 2.1 (odds ratio 2.6, 95% confidence interval 1.6-4.3) compared to population controls. The relative population risks in subgroups of PCOS patients with primary and secondary RPL were 2.3 (odds ratio 2.5, 95% confidence interval 1.2-5) and 3.3 (odds ratio 3.6, 95% confidence interval 1.5-8.4) respectively. As compared to the fertile women group, the relative risks equaled 4 (odds ratio 5, 95% confidence interval 2.3-10.8) and 6 (odds ratio 7.2, 95% confidence interval 3-17.7). Estimated relative risks for M2 carriers among PCOS RPL patients matched the values previously obtained for repeated miscarriage populations. The essential phenotypes, clinically defining PCOS, associated neither with RPL in their diagnostically relevant combinations, nor with M2 carriage as RPL risk factor in the PCOS RPL subgroups. Conclusions M2/ANXA5 seems an independent RPL risk factor in PCOS patients that progressively correlates with the number of first trimester pregnancies. From our pilot study in PCOS women it appears relevant to offer M2/ANXA5 diagnostic analysis to such patients with RPL complications, to possibly guide proper therapeutic decisions. © 2013 Elsevier Inc.

Tuttelmann F.,University of Munster | Ivanov P.,Medical University-Pleven | Dietzel C.,University of Munster | Sofroniou A.,University of Munster | And 5 more authors.
Fertility and Sterility | Year: 2013

Objective To study the influence of M2/ANXA5 for recurrent pregnancy loss (RPL), according to the timing of miscarriages and assess the male partner risk. Design Genetic association study. Setting Academic research center. Patient(s) Female patients from two academic centers in Germany and Bulgaria with two or more unexplained miscarriages were selected for this study. Male partners were available for a part of the German sample. Population controls were recruited from healthy individuals of respective populations. Intervention(s) None. Main Outcome Measure(s) Incidence of M2 carriage and odds ratios were calculated between patient and control groups, and RPL risk was evaluated. Result(s) The M2 haplotype in ANXA5 was associated with greater overall RPL risk in German and in Bulgarian women, and a trend of higher prevalence was seen for male partners of German RPL patients. The highest relative risk of M2 carriage was observed in women of both populations with "early" fetal losses between the 10th and 15th gestational weeks, which was significant in the meta-analysis. Conclusion(s) M2 carriage seems to have an RPL risk role mostly for early abortions, gestational weeks 10-15. In the first phase of pregnancy this correlates with vascular remodeling to accomplish the transition from high- to low-resistance blood vessels. © 2013 by American Society for Reproductive Medicine.

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