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Journal Article 2015; 36(Suppl 1): 29-37 PubMed PMID: 26757119 Citation  Keywords:  Aryl Hydrocarbon Hydroxylases:metabolism, Cytochrome P-450 CYP1A1:metabolism, Cytochrome P-450 CYP1A2:metabolism, Cytochrome P-450 CYP2A6:metabolism, Cytochrome P-450 CYP2B6:metabolism, Cytochrome P-450 CYP2C8:metabolism, Cytochrome P-450 CYP2C9:metabolis.   

OBJECTIVES: Cytochromes P450 (CYPs) are heme enzymes oxygenating a broad range of substrates. Their activity is dependent on the presence of a suitable electron donor (eukaryotic NADPH:CYP oxidoreductase or cytochrome b5). The Escherichia naturally contain no CYPs and no NADPH:CYP oxidoreductase, however it was reported that some CYPs heterologously expressed in E. coli may exist in the ferrous form. A small bacterial flavoprotein, flavodoxin is considered to be responsible for reduction some of these CYPs.

METHODS: The reduction state of several human CYPs expressed in the intact living E. coli cells was examined. In addition, molecular dynamics and steered molecular dynamics simulations were performed to predict and compare affinity of flavodoxin toward selected CYPs.

RESULTS: We determined the reduction state of five human CYPs heterologously expressed in E. coli. The computationally predicted stabilities of CYP-flavodoxin complexes correlate with the percentage of reduced CYPs in bacterial cells. The mean electron transfer distance within optimized complexes was also related to the percentage of reduced CYPs.

CONCLUSION: Depending on the resting state, the CYPs heterologously expressed in E. coli could be divided into two groups; CYP2C8, 2C9, 3A4 are in E. coli present mainly in the oxidized form; while CYP1A1, 1A2, 2A6, 2A13, 2B6, 2D6 are found predominantly in the reduced form. We found a significant correlation between the stability of CYP-flavodoxin complexes and the percentage of reduced CYPs in bacteria. Hence, the naturally expressed flavodoxin is probably responsible for reduction of a larger group of human CYPs in bacterial cells....

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Journal Article 2015; 36(Suppl 1): 133-140 PubMed PMID: 26757116 Citation  Keywords:  Animals, Carps:blood, Catalase:drug effects, Gills:drug effects, Glutathione Reductase:drug effects, Hematocrit, Hemoglobins:drug effects, Insecticides:toxicity, Kidney:drug effects, Liver:drug effects, Nitriles:toxicity, Oxidative Stress:drug effects, Py.   

OBJECTIVES: The aim of this study is to evaluate effects of the insecticide Decis Mega (DM; active substance deltamethrin 50 g.L(-1)) on common carp on the basis of haematological profile, oxidative stress, antioxidant enzymes and histopathology.

DESIGN: Fish were exposed two concentrations of DM 6.56 μg.L(-1) (1DM) and 65.6 μg.L(-1) (2DM) for 96 h. Then the remaining fish were transferred into DM-free water for depuration for another period of 96 h.

RESULTS: Exposure to 1DM and 2DM proved effect on enzymatic activity of superoxide dismutase, catalase, glutathione reductase and on oxidative damage of cells in gills, liver and kidney (p<0.05, p<0.01). Exposure to 1DM showed differences (p<0.05, p<0.01) in hematocrit and hemoglobin in blood. Histopathological changes were observed after acute exposure to DM as well as to DM-free water in gills, liver and kidney.

CONCLUSION: This study concludes that deltamethrin has influence on the haematological parameters, activity of antioxidant enzymes and caused oxidative damage, and histopathological changes in the fish. However, antioxidant balance in the body was restored after placing the fish in clean water for 4 days, however, this time was not sufficient complete regeneration....

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Journal Article 2015; 36(Suppl 1): 57-63 PubMed PMID: 26757114 Citation  Keywords:  Animals, Arsenic:pharmacology, Bacterial Infections:blood, Carcinogens:pharmacology, Cyanobacteria, Erythrocyte Indices:drug effects, Iron:blood, Leukocyte Count, Microcystins:pharmacology, Microcystis, Neutrophils:drug effects, Oncorhynchus mykiss:blood,.   

OBJECTIVES: Under environmental conditions, fish are simultaneously exposed to multiple stressors. This study provides new knowledge on the effects of controlled exposure to multiple stressors, namely cyanobacterial biomass and food contaminated with arsenic.

METHODS: Rainbow trout were divided into six groups of 25 fish and exposed to different contaminant combinations for 30 days: 1) control group, 2) cyanobacterial biomass, 3 & 4) two groups exposed to arsenic at concentrations of 5 mg.kg(-1) and 50 mg.kg(-1) fish feed, and 5 & 6) two groups exposed to cyanobacterial biomass and arsenic combined. We then evaluated pathological, haematological and immunological parameters at 10, 20 and 30 days after exposure.

RESULTS: Marked gross pathological findings were present in groups exposed to arsenic and arsenic/cyanobacteria after 30 days. A strong decrease in haemoglobin concentration was observed in all experimental groups receiving arsenic after 10 days exposure. Total leukocyte count increased markedly in fish exposed to cyanobacterial biomass, and to higher arsenic concentrations by the end of the experiment. Neutrophils decreased significantly at the end of exposure. Similarly, exposure to cyanobacteria and/or arsenic led to suppression of opsonised zymosan particle-induced neutrophil respiratory bursts.

CONCLUSIONS: Our results demonstrate that the effects of exposure to toxic cyanobacterial biomass and arsenic on fish are enhanced when the contaminants are combined. In particular, long-term exposure led to disturbances in the white blood-cell count. Modulation of phagocytosis, which is the first line of defence against invading pathogens, suggests that the combined action leads to a decreased ability to control infection....

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Journal Article 2015; 36(Suppl 1): 126-132 PubMed PMID: 26757111 Citation  Keywords:  Animals, Cadmium:analysis, Chromium:analysis, Czech Republic, Fishes, Geologic Sediments:chemistry, Lead:analysis, Mercury:analysis, Metals, Heavy:analysis, Muscle, Skeletal:chemistry, Poisoning, Rivers, Water Pollutants, Chemical:analysis, Zinc:analysis,.   

OBJECTIVES: The monitoring survey to assess the environmental pollution status of the river Morava--was carried out in 2014.

DESIGN: This study presents the concentrations of heavy metals (Hg, Cr, Zn, Pb and Cd) in the water, sediment and muscle tissue of fish from the middle and lower reaches of the Morava river basin (Bečva, Dřevnice, Haná, Kyjovka and Morava rivers), in the Czech Republic. Atomic absorption spectrometry (AAS) was used for the analysis of toxic metals. European chub (Squalius cephalus) was chosen as a reference fish species for the comparison of monitored localities.

RESULTS: Results showed a positive significant correlation between concentration of Hg, Pb, Cd, Cr and Zn in muscles and age of fishes (p<0.05). The contents of the analyzed metals in European chub muscles were low Hg 0.049-0.402, Pb 0.005-0.035, Cd 0.006-0.026, Cr 0.016-0.042 and Zn 5.59-64.31 mg.kg(-1) wet weight basis and did not exceed the values of limits admissible in the Czech Republic.

CONCLUSIONS: The contents of the analyzed metals in European chub muscles were low at monitoring sites and did not exceed the values of limits admissible in the Czech Republic....

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Comparative Study 2015; 36(Suppl 1): 141-146 PubMed PMID: 26757110 Citation  Keywords:  Aminobenzoates:pharmacology, Anesthetics:pharmacology, Animals, Clove Oil:pharmacology, Cyprinidae, Ethylene Glycols:pharmacology, Etomidate:pharmacology, Gills:drug effects, Glutathione Reductase:drug effects, Liver:drug effects, Muscle, Skeletal:drug ef.   

OBJECTIVES: Currently, many questions regarding the effect of anaesthetics to fish remain unresolved. Fish species may differ widely in their response to an anaesthetic, the screening of dosages is often necessary. The aim of this study was to compare the effect of tricaine methane sulphonate (MS 222), clove oil, 2-phenoxyethanol and Propiscin on haematological profiles, oxidative stress biomarkers and antioxidant enzymes in barbel (Barbus barbus).

DESIGN: The haematological profiles, oxidative stress biomarkers and antioxidant enzymes of barbel were evaluated immediately after a 10 min anaesthesia (MS 222--100 mg.L(-1), clove oil--33 mg.L(-1), 2-phenoxyethanol--0.4 mg.L(-1), Propiscin--1.0 mg.L(-1)), and 24 h after anaesthesia.

RESULTS: The 10 min exposure in the recommended concentrations of tested anaesthetics have no significant effect on haematological profiles, levels of thiobarbituric acid reactive substances, and activity of glutathione reductase of barbel. The activity of superoxide dismutase (SOD) was significantly decreased (p<0.01) in the muscle in all experimental groups. The activity of SOD showed a significant decrease (p<0.01) in the liver 24 h after all anaesthetics; however in the gill the activity of SOD was significantly increased (p<0.01) in Propiscin (10 min). The activity of catalase (CAT) was significantly increased (p<0.05) in the muscle 24 h after all anaesthetics.

CONCLUSIONS: The observed effects on barbel antioxidant systems may be a defence against oxidative damage. The results of this study suggest that the antioxidant systems of barbel are altered by Propiscin anaesthesia, but are slightly affected by MS 222, clove oil, and 2-phenoxyethanol anaesthesia....

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Journal Article 2015; 36(Suppl 1): 106-113 PubMed PMID: 26757109 Citation  Keywords:  Desulfovibrio:drug effects, Humans, Intestine, Large:microbiology, Microbial Sensitivity Tests, Microbial Viability:drug effects, Salicylamides:pharmacology,.   

OBJECTIVES: The aim of our work was to evaluate effect of selected salicylamides on cell viability of sulfate-reducing bacterium Desulfovibrio piger Vib-7 isolated from the human large intestine, as well as to assess antimicrobial activity and biological properties of these compounds.

METHODS: Microbiological, biochemical, biophysical methods, and statistical processing of the results were used.

RESULTS: An antimicrobial activity and biological properties of salicylamides against intestinal sulfate-reducing bacteria was studied. Primary in vitro screening of the synthesized selected salicylamides was performed against D. piger Vib-7. Adding 0.37-1.10 µmol.L(-1) (N-(4-bromophenyl)-5-chloro-2-hydroxybenzamide, 5-chloro-2-hydroxy-N-[4-(trifluoromethyl)phenyl]benzamide, 5-chloro-N-(3,4-dichlorophenyl)-2-hydroxybenzamide, 5-chloro-2-hydroxy-N-(4-nitrophenyl)benzamide and 4-chloro-N-(3,4-dichlorophenyl)-2-hydroxybenzamide) caused decrease in biomass accumulation by 8-53, 64-66, 49-50, 82-90, 43-46% compared to control, respectively. The studied compounds completely inhibited the growth of D. piger Vib-7 under the effect of 30 µmol.L(-1). Moreover, addition of the compounds in the culture medium inhibited the process of dissimilation sulfate dose dependently. Treatment with salicylamides led to the bacterial growth inhibition which correlated with the level of inhibition of sulfate reduction. The data on relative survival of D. piger Vib-7 cells and cytotoxicity of salicylamides are consistent to our research in previous series of the biomass accumulation experiments.

CONCLUSIONS: A significant cytotoxic activity under the influence of salicylamides was determined. These results are consistent with a data on bacterial growth and inhibition process of dissimilation sulfate. The strongest cytotoxic effect of the derivatives was observed in compounds of 5-chloro-2-hydroxy-N-[4-(trifluoromethyl)phenyl]benzamide and 5-chloro-2-hydroxy-N-(4-nitrophenyl)benzamide which showed low survival and high toxicity rates....

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Journal Article 2015; 36(Suppl 1): 5-12 PubMed PMID: 26757108 Citation  Keywords:  Animals, Aryl Hydrocarbon Hydroxylases:metabolism, Chromatography, High Pressure Liquid, Cytochrome P-450 CYP1A1:metabolism, Cytochrome P-450 CYP3A:metabolism, Cytochrome P-450 Enzyme System:metabolism, Cytochrome P450 Family 2, Ethinyl Estradiol:metaboli.   

OBJECTIVES: 17α-Ethinylestradiol (EE2) is an endocrine disruptor that is an ingredient of oral contraceptives. Here, EE2 metabolism catalyzed by cytochromes P450 (CYP) was studied. Two model organisms, rat and ligninolytic fungus Pleurotus ostreatus, were used.

METHODS: To resolve the role of rat and/or fungal CYPs in EE2 oxidation, microsomes were incubated with EE2 and NADPH or cumene hydroperoxide. Using Supersomes™, we examined which of rat CYPs oxidize EE2.

RESULTS: EE2 is effectively degraded by P. ostreatus in vivo. In vitro, EE2 is metabolized by CYPs by the NADPH-dependent and organic hydroperoxide-dependent mechanisms. Rat hepatic microsomes metabolize EE2 in the presence of NADPH to three products; two of them are hydroxylated EE2 derivatives. Using rat Supersomes™ we found that EE2 is hydroxylated by several rat CYPs, among them CYP2C6 and 2C11 are most efficient in 2-hydroxy-EE2 formation, while CYP2A and 3A catalyze EE2 hydroxylation to the second product. On the contrary, the products of the NADPH-dependent hydroxylating reactions were not detected in Pleurotus ostreatus. During the reaction of EE2 in microsomes isolated from rat and P. ostreatus in the presence of the alternate oxidant, cumene hydroperoxide, another metabolite, different from the above mentioned products, is generated. Rat CYP1A1 is the most efficient enzyme catalyzing formation of this EE2 product.

CONCLUSION: The results suggest that CYPs play a role in EE2 metabolism in rat and P. ostreatus. To our knowledge this is the first finding describing ligninolythic fungal metabolism of EE2 by CYP in the presence of cumene hydroperoxide....

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Journal Article 2015; 36(Suppl 2): 35-42 PubMed PMID: 26748525 Citation  Keywords:  Adipose Tissue:physiology, Adult, Blood Pressure:physiology, Body Mass Index, Czech Republic:ethnology, Female, Humans, Male, Middle Aged, Obesity:ethnology, Overweight:ethnology, Roma:ethnology, Sex Factors, Waist Circumference:physiology,.   

OBJECTIVES: The objective of our correlation study was to compare selected indicators of overweight and obesity of Roma and non-Roma (majority) populations in the South Bohemia Region or the Czech Republic.

METHODS: The following indicators were chosen for evaluation of overweight and obesity: body height and weight, waistline measurement, waist/height index, waist/hips index, BMI, total fat and blood pressure. 600 participants were examined and interviewed in total, including 302 Roma and 298 non-Roma participants. Each of the participants had a personal examination performed by a general nurse, under hygienic-epidemiological conditions. The criteria for inclusion of participants into the study were consent with examination and age greater than 18 years.

RESULTS: The statistical analysis showed that, at a level of significance of p < 0.001, the following values differed between the Roma and non-Roma population of the South Bohemia Region: waist/height index, waistline, total fat, body mass index (BMI), systolic and diastolic blood pressure. Differences in the incidence of the waist/hips index were significant at p < 0.01. Correlations of incidence with indicators of overweight and obesity in Roma were registered in relation to both age and gender of participants. The results show that overweight and obesity indicators were recorded more frequently in Roma female respondents. Although the results are unique, the conclusions cannot be generalized for Roma throughout the Czech Republic.

CONCLUSION: The conclusions of the above findings will be implemented in strategic materials for community planning in the South Bohemia Region. The goal will be to offer services aimed at supporting a healthy life style for Roma living in the South Bohemia Region of the Czech Republic....

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