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Journal Article 2012; 33(Suppl 3): 161-165 PubMed PMID: 23353861 Citation  Keywords:  Animals, Bacterial Toxins:toxicity, Biomass, Body Weight, Carcinogens:toxicity, Chemical and Drug Induced Liver Injury:epidemiology, Coturnix, Cyanobacteria:chemistry, Dose-Response Relationship, Drug, Hepatocytes:drug effects, Lethal Dose 50, Male, Marin.   

OBJECTIVES: Previous studies using oral administration of environmentally relevant doses of cyanobacterial biomass containing microcystins (MCs) induced only sub-lethal effects in experimental birds. Therefore, the objective of this study was to obtain data on avian high-dose toxicity of MCs and compute LD50, if possible, following the natural oral route of administration.r />r /> DESIGN: Responses of birds to single high-dose exposure to MCs were evaluated in fourteen-day old Japanese quail males (Coturnix coturnix japonica) with average body weight of 50 g which were randomly divided into five groups. Birds from four experimental groups were administered 7.5 ml of cyanobacterial biomass suspension containing increasing MCs quantities of 2500, 5000, 10000, and 20000 µg/kg using oral gavage. Controls received an equal dose of drinking water instead of the test substance. Birds were observed for clinical signs of acute toxicity. Survivors were killed on day 5 to obtain body and liver weights. A five-grade semi-quantitative system for histopathological liver damage scoring was used to compare cyanobacterial-biomass-exposed birds against controls.r />r /> RESULTS: No mortality occurred during the period of five days post exposure in both control and MCs-exposed groups and this high-dose experiment failed to provide data to compute the LD50. Nevertheless, marked sub-lethal effects were recognised in the damage of liver that included dose-dependent changes in the body/liver ratios and morphological changes ranging from mild vacuolar dystrophy to focal liver necroses in the highest exposure group. Hepatic lesions were mainly observed in the pericentral area of the liver.r />r /> CONCLUSIONS: Though maximum cyanobacterial biomass dose rates that could be administered to birds of the size were used in the present experiment and more pronounced hepatic lesions than after exposure to environmentally relevant doses were observed, birds would probably have survived unless killed for histopathology on day 5 of exposure. These results provide support to previously reported data on sub-lethal effects following exposure to cyanobacterial biomass containing MCs in birds and mortality occurring only in birds under combined action with other stressors....

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Journal Article 2012; 33(Suppl 3): 155-160 PubMed PMID: 23353860 Citation  Keywords:  4-Hydroxycoumarins:toxicity, Animals, Anticoagulants:toxicity, Biomass, Brain:drug effects, Carcinogens:toxicity, Cholinesterase Inhibitors:toxicity, Coturnix, Cyanobacteria:chemistry, Female, Heart:drug effects, Kidney:drug effects, Liver:drug effects, L.   

OBJECTIVES: The objective of this study was to examine the hypothesis that a combination of cyanobacterial biomass containing microcystins, acetylcholinesterase inhibitor and anticoagulant can enhance avian toxic effects produced by single exposures only.r />r /> METHODS: A total of 48 two-month-old Japanese quails (Coturnix coturnix japonica) with average body weight of 160 g were randomly divided into 8 experimental groups of six birds and sex ratio of 1:1. Experimental groups of control Japanese quails (C) and birds exposed to single and combined sub-lethal doses of paraoxon (P), bromadiolone (B), and microcystins in cyanobacterial biomass (M) included: C, P, P+B, B, B+M, P+M, M, and P+B+M. During the 10-day exposure birds in the respective groups received biomass containing 61.62 µg microcystins daily (i.e. 26.54 µg MC-RR, 7.62 µg MC-YR and 27.39 µg MC-LR), two 250 μg/kg doses of paraoxon, and two 500 mg/kg doses of bromadiolone. Group responses were compared using standard plasma biochemistry and antioxidant/oxidative stress parameters in tissues.r />r /> RESULTS: While single and double combinations of toxicants induced responses in individual biochemical parameters measured and evaluated using univariate statistical analysis, those in the triple exposure were most extensive. The principal component analysis of antioxidant/oxidative stress parameters (glutathione reductase, lipid peroxidation, and ferric reducing antioxidant power) in tissues (liver, kidney, heart, brain, lungs, gonads, and pectoralis major muscle) clearly separated the triple group (P+B+M) from all single and double exposure groups and the control and indicated thus marked joint effects in the overall pattern of antioxidant/oxidative stress responses of this group. The separation was driven by the modification of the ferric reducing antioxidant power levels in heart and brain and the cardiac lipid peroxidation level, in particular.r />r /> CONCLUSIONS: This experiment contributes to the understanding of the pathogenic mechanisms of combined sub-lethal exposure to natural toxins and agrochemicals and may be used for risk assessment of environmental pollution in birds....

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Journal Article 2012; 33(Suppl 3): 151-154 PubMed PMID: 23353859 Citation  Keywords:  Antioxidants:chemistry, Ascorbic Acid:chemistry, Copper:chemistry, Cysteine:analogs & derivatives, Extracellular Matrix:chemistry, Free Radicals:chemistry, Humans, Hyaluronic Acid:chemistry, Molecular Weight, Oxidation-Reduction, Spectroscopy, Fourier Tra.   

OBJECTIVES: Hyaluronan (HA), one of the main components of extracellular matrix, is a glycosaminoglycan composed of repeating disaccharide units of N-acetyl-d-glucosamine and d-glucuronic acid linked by β-(1→4) and β-(1→3) glycoside bonds. High-molar-mass HA was used as a model for studying its oxidative degradation. In the present paper protective effects of bucillamine against the free-radical degradation of HA were investigated. The HA fragments generated were characterized as well.r />r /> METHODS: To induce free-radical-mediated degradation of high-molar-mass HA under aerobic conditions, we applied Weissberger's oxidative system, comprising biogenic compounds in relevant pathophysiological concentrations, i.e. 100 µM ascorbate plus 1 µM Cu(II). Time-dependent decreases of dynamic viscosity of the HA solutions were recorded by rotational viscometry. Electron donor behaviors of bucillamine were studied by a standard ABTS test method and a chemiluminescence (CL) assay. Ability of incorporation of generated bucillamine thiyl radicals into the biopolymer was verified by Fourier-transform infrared spectroscopy (FT-IR) and size exclusion chromatography with a multi-angle light scattering photometer (SEC-MALS).r />r /> RESULTS: Decrease of HA viscosity reflected HA degradation. The drug tested was applied in two arrangements: to prevent •OH radical generation (1) and ROO• type radicals propagation (2). Bucillamine, which acted as an efficient •H donor, is also a proper electron donor, as proved by ABTS and CL assays. FT-IR and SEC-MALS methods showed that the drug tested did not incorporate into the biopolymer chains.r />r /> CONCLUSION: Bucillamine significantly protected high-molar-mass HA against free-radical degradation in vitro, and supposedly this positive action of the drug may be involved in its beneficial effect observed in clinical practice....

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Journal Article 2012; 33(Suppl 3): 145-150 PubMed PMID: 23353858 Citation  Keywords:  Animals, Anti-Inflammatory Agents, Non-Steroidal:toxicity, Blood Proteins:metabolism, Coturnix, Diclofenac:toxicity, Drug Synergism, Environmental Pollutants:toxicity, Gastrointestinal Tract:drug effects, Hemoglobins:metabolism, Lead:toxicity, Lead Poison.   

OBJECTIVES: Pharmaceuticals and heavy metals such as diclofenac and lead, respectively, have been identified as environmental contaminants toxic to birds and posing serious threats to declining populations of raptors worldwide. The aim of the present study was to test the hypothesis that a sublethal combination of non-steroidal anti-inflammatory drugs and lead induces more pronounced effects than single exposures in birds.r />r /> METHODS: A total of 40 Japanese quails (Coturnix coturnix japonica) at the age of 2 months and average weight of 180g were on a random basis divided into four experimental groups of 10 specimens (i.e., control, diclofenac, lead, and lead+diclofenac exposures). Six lead shots in the total weight of 1.5 grams were inserted into the crop on day 0 of the experiment, while a total of 5 mg/kg of diclofenac administered intramuscularly were divided into treatments on days 0 and 5. Group responses were compared using haematology and biochemistry after 10 days.r />r /> RESULTS: There was no mortality in control and both single and combined diclofenac and lead exposure groups, nor did the birds show any clinical signs of intoxication. Univariate analyses of blood parameters yielded a decrease in haematocrit in birds exposed to both substances when compared with the control, a lower haemoglobin level of the lead-exposed group, increased activity of aspartate aminotransferase in the NSAIDs-exposed group, increased activity of alkaline phosphatase in birds exposed to a combination of diclofenac and lead, and a higher phosphorus level in the lead-exposed group. The principal component analysis revealed no multivariate pattern of responses of blood parameters and did not allow separation of exposure groups from controls when the variables and samples were projected onto a two dimensional space.r />r /> CONCLUSIONS: Results of the present study can enhance understanding of combination toxicity of veterinary drugs and heavy metals in birds, i.e. a scenario that has become environmentally relevant in recent decades. Fortunately, individual blood parameter effects prevailed and no joint mortal effects were recognised in Japanese quails exposed to a combination of sublethal doses of diclofenac and lead....

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Journal Article 2012; 33(Suppl 3): 136-144 PubMed PMID: 23353857 Citation  Keywords:  Alzheimer Disease:chemically induced, Animals, Antioxidants:metabolism, Brain:drug effects, Caspase 3:metabolism, Chemical and Drug Induced Liver Injury:metabolism, Cholinesterase Inhibitors:toxicity, Disease Models, Animal, Female, Guinea Pigs, Heart:dru.   

OBJECTIVES: Tacrine was the first acetylcholinesterase inhibitor approved for the treatment of Alzheimer disease. The compound is not available for therapeutic purposes as it was withdrawn due to hepatotoxicity of its metabolites. The hepatotoxicity can be decreased by alternative ways of drug administration avoiding thus the first pass effect. The present study is aimed to investigate the influence of intramuscularly administrated tacrine on oxidative stress.r />r /> METHODS: Laboratory guinea pigs were exposed to tacrine at doses of 0-800 μg/kg. The animals were euthanized 1 and 24 hours after the exposure. Parameters such as ferric reducing antioxidant power (FRAP), thiobarbituric acid reactive substances (TBARS), carbonylated proteins, caspase 3 activity, superoxide dismutase activity and glutathione reductase activity were assessed in the frontal, temporal and occipital lobe, cerebellum, liver, spleen, heart, and kidney. Moreover, levels of glucose, total and HDL cholesterol forms, triglycerides, blood urea nitrogen, creatinine, total bilirubin, total protein, albumin and activities of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase and lactate dehydrogenase were assessed in plasma samples.r />r /> RESULTS: Activities of the enzymatic markers, level of carbonylated proteins in organs and levels of biochemical markers in plasma were only slightly influenced by tacrine. Dose-dependent elevation of the FRAP value was recognized in the brain tissues and the liver. The TBARS value was increased in the kidney and heart 1 and 24 hours, respectively, after exposure.r />r /> CONCLUSION: In the study, the effect of tacrine on markers of oxidative stress was proved. Possible positive effects of tacrine on the antioxidant defence in the brain tissue were discussed....

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Journal Article 2012; 33(Suppl 3): 130-135 PubMed PMID: 23353856 Citation  Keywords:  Animals, Antioxidants:metabolism, Biomarkers:metabolism, Carps:embryology, Catalase:metabolism, Czech Republic, Embryo, Nonmammalian:drug effects, Female, Glutathione Reductase:metabolism, Herbicides:toxicity, Male, Oxidative Stress:drug effects, Prometry.   

OBJECTIVES: The aim of the study was to investigate effects of the triazine herbicide prometryne on early life stages of common carp Cyprinus carpio as indicated by oxidative stress and antioxidant indices.r />r /> DESIGN: Toxicity tests were performed according to OECD 210 methodologies. Common carp larvae and embryos exposed for 35 days to prometryne at three concentrations, 0.51 (reported concentration in Czech rivers), 80 (1% 96 h LC50), and 1200 (15% 96 h LC50) μg/l, were compared to carp in a non-treated control group. Activity of superoxide dismutase (SOD), catalase (CAT), and glutathione reductase (GR), as well as levels of thiobarbituric acid reactive substances (TBARS) were assessed.r />r /> RESULTS: Chronic exposure of early life stages of carp to prometryne showed no effect on growth and mortality rates. Levels of oxidative damage in fish test groups showed no significant differences from the controls. Glutathione reductase activity at exposure 0.51 μg/l was significantly increase (p<0.01) compared with controls and other exposures.r />r /> CONCLUSION: The chronic exposure to prometryne showed no influence on oxidative stress. Differences from control fish was observed in GR activity in exposure prometryne 0.51 μg/l....

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Journal Article 2012; 33(Suppl 3): 124-129 PubMed PMID: 23353855 Citation  Keywords:  Animals, Biomarkers:metabolism, Carps:embryology, Dose-Response Relationship, Drug, Embryo, Nonmammalian:drug effects, Free Radicals:metabolism, Herbicides:toxicity, Lipid Peroxidation:drug effects, Oxidative Stress:drug effects, Phenols:metabolism, Plant.   

OBJECTIVES: This work assessed the subchronic effects of the triazine compounds terbuthylazine and metribuzin on embryo-larval stages of common carp (Cyprinus carpio L.) using biotransformation enzyme and selected oxidative stress parameters.r />r /> DESIGN: Early developmental stages of fish, from embryo to larvae, were exposed to terbuthylazine at concentrations of 0.9, 160, 520, and 820 μg/L, and metribuzin at concentrations of 0.9, 4, 14, and 32 mg/L for 30 days and compared to the non-treated control group. For assessment of free radical defence the activities of glutathione S-transferase (GST) and glutathione reductase (GR) were measured; the lipid peroxidation (TBARS) level was determined as a marker of free radical damage.r />r /> RESULTS: Terbuthylazine had no significant effect (p>0.05) at any tested concentrations on GST activity. Terbuthylazine caused an increase (p<0.05) in GR activity at the concentration of 520 μg/L. We found a non-significant (p>0.05) effect of terbuthylazine exposure on TBARS level. In metribuzin treated groups, the activity of GST was increased (p<0.05) in all experimental groups, with the highest at the concentration of 32 mg/L. GR activity was increased in the 0.9, 4, and 14 mg/L groups and the TBARS levels were the highest in the 0.9 mg/L group.r />r /> CONCLUSION: Our results suggest that terbuthylazine and metribuzin induced oxidative stress in embryo-larval stages of common carp. Increased activities of biotransformation enzymes or antioxidant defence enzymes were markers of free radical attack. There was low lipid peroxidation in early developed fish after triazine exposure....

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Journal Article 2012; 33(Suppl 3): 120-123 PubMed PMID: 23353854 Citation  Keywords:  Animal Feed, Animals, Aquaculture:methods, Bacterial Toxins:toxicity, Carps:growth & development, Cryopreservation, Cyanobacteria, Ecosystem, Marine Toxins:toxicity, Microcystins:toxicity, Muscle, Skeletal:anatomy & histology, Oncorhynchus mykiss:growth &.   

OBJECTIVES: Cyanobacteria are studied from the viewpoint of the issue of risks to water supply, agriculture and recreational activities for a long time. Cyanobacteria produce a wide range of substances which can be toxic and can influence the safety and quality of fish products. The aim of this study was to determine whether the diet with the content of cyanobacteria can affect the water activity and the dry matter of fish muscle and whether this diet can contribute significantly to the shelf life of fish muscles.r />r /> METHODS: Common carp (Cyprinus carpio) and rainbow trout (Oncorhynchus mykiss) were used in this study. Both fish species were divided into two groups. The first group of fish was fed with feed with cyanobacteria (3% of dry matter), the second group with feed without cyanobacteria. The water activity and the dry matter were monitored immediately after sampling of the fish muscle on day 7, 14 and 21 (carp) or on day 10, 20 and 30 (rainbow trout) and seven days after every sampling and cold storage (6-8 °C).r />r /> RESULTS: Feed with the content of cyanobacteria significantly decreased the water activity in muscles of both fish species on day 21 (in carp) and on day 30 (in rainbow trout). The dry matter of fish muscle significantly increased on day 7 and 21 (in carp) and on day 10 and 30, but decreased on day 20 (in rainbow trout). The cold storage significantly influenced the dry matter only. While the dry matter was increased in the common carp (7 days of cold storage after sampling on days 14 and 21), the dry matter decreased in the rainbow trout (7 days of cold storage after sampling on day 10).r />r /> CONCLUSIONS: The decrease of water activity was found only after longer exposure in the both exposed fish species. The dry matter was influenced far greater and was mostly increased in the both exposed fish species....

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