Cyanobacteria routinely release potentially harmful bioactive compounds into the aquatic environment. Several recent studies suggested a potential link between the teratogenicity of effects caused by cyanobacteria and production of retinoids. To investigate this relationship, we analysed the teratogenicity of field-collected cyanobacterial bloom samples by means of an in vivo zebrafish embryo test, an in vitro reporter gene bioassay and by the chemical analysis of retinoids. Extracts of biomass from cyanobacterial blooms with the dominance of Microcystis aeruginosa and Aphanizomenon klebahnii were collected from water bodies in the Czech Republic and showed significant retinoid-like activity in vitro, as well as high degrees of teratogenicity in vivo. Chemical analysis was then used to identify a set of retinoids in ng per gram of dry weight concentration range. Subsequent fractionation and bioassay-based characterization identified two fractions with significant in vitro retinoid-like activity. Moreover, in most of the retinoids eluted from these fractions, teratogenicity with malformations typical for retinoid signalling disruption was observed in zebrafish embryos after exposure to the total extracts and these in vitro effective fractions. The zebrafish embryo test proved to be a sensitive toxicity indicator of the biomass extracts, as the teratogenic effects occurred at even lower concentrations than those expected from the activity detected in vitro. In fact, teratogenicity with retinoid-like activity was detected at concentrations that are commonly found in biomasses and even in bulk water surrounding cyanobacterial blooms. Overall, these results provide evidence of a link between retinoid-like activity, teratogenicity and the retinoids produced by cyanobacterial water blooms in the surrounding environment.

• Klíčová slova
• All-trans retinoic acid, Cyanobacteria, Retinoid-like activity, Retinoids, Teratogenicity, Zebrafish,
• MeSH
• Aphanizomenon patogenita   MeSH
• dánio pruhované embryologie   genetika   MeSH
• embryo nesavčí účinky léků   MeSH
• Microcystis patogenita   MeSH
• reportérové geny MeSH
• retinoidy biosyntéza   toxicita   MeSH
• sinice chemie   patogenita   MeSH
• teratogeny toxicita   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika MeSH
• Názvy látek
• retinoidy MeSH
• teratogeny MeSH

This is a simple protocol for the quantitative determination of phycobiliprotein content in the model cyanobacterium Synechocystis. Phycobiliproteins are the most important components of phycobilisomes, the major light-harvesting antennae in cyanobacteria and several algae taxa. The phycobilisomes of Synechocystis contain two phycobiliproteins: phycocyanin and allophycocyanin. This protocol describes a simple, efficient, and reliable method for the quantitative determination of both phycocyanin and allophycocyanin in this model cyanobacterium. We compared several methods of phycobiliprotein extraction and spectrophotometric quantification. The extraction procedure as described in this protocol was also successfully applied to other cyanobacteria strains such as Cyanothece sp., Synechococcuselongatus, Spirulina sp., Arthrospira sp., and Nostoc sp., as well as to red algae Porphyridium cruentum. However, the extinction coefficients of specific phycobiliproteins from various taxa can differ and it is, therefore, recommended to validate the spectrophotometric quantification method for every single strain individually. The protocol requires little time and can be performed in any standard life science laboratory since it requires only standard equipment.

• MeSH
• fykobiliproteiny metabolismus   MeSH
• rostlinné proteiny metabolismus   MeSH
• sinice patogenita   MeSH
• spektrofotometrie metody   MeSH
• Synechocystis patogenita   MeSH
• Publikační typ
• audiovizuální média MeSH
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• fykobiliproteiny MeSH
• rostlinné proteiny MeSH

Microcystins (MCs) are primarily hepatotoxins produced by cyanobacteria and are responsible for intoxication in humans and animals. There are many incidents of chronic exposure to MCs, which have been attributed to the inappropriate treatment of water supplies or contaminated food. Using RAW 264.7 macrophages, we showed the potency of microcystin-LR (MC-LR) to stimulate production of pro-inflammatory cytokines (tumor necrosis factor α and interleukin-6) as a consequence of fast nuclear factor κB and nitrogen-activated protein kinase activation. In contrast to other studies, the observed effects were not attributed to the intracellular inhibition of protein phosphatases 1/2A due to lack of specific transmembrane transporters for MCs. However, the MC-LR-induced activation of macrophages was effectively inhibited by a specific peptide that blocks signaling of receptors, which play a pivotal role in the innate immune responses. Taken together, we showed for the first time that MC-LR could interfere with macrophage receptors that are responsible for triggering the above-mentioned signaling pathways. These findings provide an interesting mechanistic explanation of some adverse health outcomes associated with toxic cyanobacteria and MCs.

• MeSH
• buněčné linie účinky léků   MeSH
• chemické látky znečišťující vodu toxicita   MeSH
• imunologické faktory toxicita   MeSH
• interleukin-6 metabolismus   MeSH
• makrofágy účinky léků   metabolismus   patologie   MeSH
• mikrocystiny toxicita   MeSH
• mořské toxiny MeSH
• myši MeSH
• NF-kappa B metabolismus   MeSH
• přirozená imunita účinky léků   MeSH
• proteinfosfatasa 2 metabolismus   MeSH
• sinice patogenita   MeSH
• testy chronické toxicity metody   MeSH
• TNF-alfa metabolismus   MeSH
• zánět chemicky indukované   imunologie   metabolismus   MeSH
• zásobování vodou MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• chemické látky znečišťující vodu MeSH
• cyanoginosin LR MeSH Prohlížeč
• imunologické faktory MeSH
• interleukin-6, mouse MeSH Prohlížeč
• interleukin-6 MeSH
• mikrocystiny MeSH
• mořské toxiny MeSH
• NF-kappa B MeSH
• proteinfosfatasa 2 MeSH
• TNF-alfa MeSH

OBJECTIVES: Under environmental conditions, fish can be exposed to multiple stressors including natural toxins and infectious agents at the same time. This study brings new knowledge on the effects of controlled exposure to multiple stressors in fish. The aim of this study was to test the hypothesis that influence of cyanobacterial biomass and an infection agent represented by the white spot disease can combine to enhance the effects on fish. METHODS: Common carps were divided into four groups, each with 40 specimens for 20 days: control group, cyanobacterial biomass exposed group, Ichthyophthirius multifiliis-infected fish (Ich) and cyanobacterial biomass-exposed fish + Ichthyophthirius multifiliis-infected fish. During the experiment we evaluated the clinical signs, mortality, selected haematological parameters, immune parameters and toxin accumulation. RESULTS: There was no mortality in control fish and cyanobacterial biomass-exposed fish. One specimen died in Ichthyophthirius multifiliis-infected fish and the combined exposure resulted in the death of 13 specimens. The whole leukocyte counts (WBC) of the control group did not show any significant differences. Cyanobacteria alone caused a significant increase of the WBC on day 13 (p≤0.05) and on day 20 (p≤0.01). Also, I. multifiliis caused a significant elevation of WBC (p≤0.01) on day 20. Co-exposition resulted in WBC increased on day 13 and decrease on day 20, but the changes were not significant. It is evident from the differential leukocyte counts that while the increase of WBC in the group exposed to cyanobacteria was caused by elevation of lymphocytes, the increase in the group infected by I. multifiliis was due to the increase of myeloid cells. It well corresponds with the integral of chemiluminescence in the group infected by I. multifiliis, which is significantly elevated on day 20 in comparison with all other groups. CONCLUSIONS: We can confirm additive action of different agents on the immune system of fish. While single agents seemed to stimulate the immune response, the combination of both caused immunosuppression.

• MeSH
• bakteriální toxiny toxicita   MeSH
• biomasa MeSH
• Ciliophora MeSH
• fyziologický stres imunologie   MeSH
• imunitní systém imunologie   MeSH
• kapři imunologie   MeSH
• karcinogeny toxicita   MeSH
• mikrocystiny toxicita   MeSH
• mořské toxiny toxicita   MeSH
• nemoci ryb imunologie   mikrobiologie   parazitologie   MeSH
• počet leukocytů MeSH
• protozoální infekce imunologie   MeSH
• sinice růst a vývoj   patogenita   MeSH
• toxiny kmene Cyanobacteria MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• bakteriální toxiny MeSH
• karcinogeny MeSH
• mikrocystiny MeSH
• mořské toxiny MeSH
• toxiny kmene Cyanobacteria MeSH

OBJECTIVES: The toxic cyanobacteria are a serious problem for water supply systems, recreation, and agriculture. Cyanobacteria produce numerous bioactive compounds including microcystins - the most studied cyanobacterial hepatotoxins. Only rare studies addressed realistic situation, i.e. impact of MCs accumulated in the fish tissues on the overall physiology. The aim of the present study was to provide a model simulation of the simple food chain for evaluation of impacts of cyanobacteria on the rat physiology under different exposure scenario. METHODS: Experimental rats were fed with food with fish meat, which contained external additions of isolated microcystins as well as toxic cyanobacteria Microcystis, nontoxic cyanobacteria Arthrospira and green alga Chlorella. Subgroups of the animals were also challenged with a model antigen KLH to investigated immune-related parameters. We studied parameters of oxidative stress in the liver as levels of lipid peroxidation and glutathion levels. Series of hematological, biochemical and immunological parameters were also investigated. RESULTS: Although considerable amounts of microcystins were administered to rats, all levels of MCs were under the detection limit (1 ng/g fresh weight) in the rat tissues using tandem LC/MS. Only some conjugates of microcystins with cystein and glutathion were detected in the rat liver exposed to Microcystis biomass (values were around the detection limit). Statistically significant depletion of body and liver weight was observed in groups with microcystin addition in comparison with all other groups. Rats exposed to MCs had stimulated immune system (showed higher antibody answer on administered antigen). Also modulation of some lymphocyte subpopulations was recorded with the most interesting observation of stimulated NK cell numbers in groups exposed to isolated toxins (but not to biomass containing the same toxin amount). CONCLUSIONS: Our study demonstrates that oral exposure to microcystins in the diet may induce some detoxification responses and modulation of some hematological and immunological parameters.

• MeSH
• aplikace orální MeSH
• bakteriální toxiny farmakologie   toxicita   MeSH
• glutathion metabolismus   MeSH
• kontaminace potravin MeSH
• krysa rodu Rattus MeSH
• laboratorní zvířata * MeSH
• mikrocystiny farmakologie   toxicita   MeSH
• mořské toxiny farmakologie   toxicita   MeSH
• peroxidace lipidů účinky léků   MeSH
• potkani Wistar * MeSH
• přijímání potravy fyziologie   MeSH
• rybí výrobky toxicita   MeSH
• sinice patogenita   fyziologie   MeSH
• toxiny kmene Cyanobacteria MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• hodnotící studie MeSH
• práce podpořená grantem MeSH
• Názvy látek
• bakteriální toxiny MeSH
• glutathion MeSH
• microcystin MeSH Prohlížeč
• mikrocystiny MeSH
• mořské toxiny MeSH
• toxiny kmene Cyanobacteria MeSH

Oxidative stress is one of the biochemical mechanisms involved in toxicity of cyanobacterial toxins microcystins (MC), but its role in the effects of complex water blooms is elusive. The aim of this study was to investigate effects of pure MCs and different complex mixtures of cyanobacterial metabolites on the growth and biochemical markers of oxidative stress and detoxification in green alga Pseudokirchneriella subcapitata. Pure MCs at high concentrations (300 μg/L) had no effects on the growth of P. subcapitata (up to 10 day exposures) but stimulated activity of glutathione reductase (GR) after short 3 and 24 h exposures. Other biomarkers (levels of glutathione, GSH, and activities of glutathione-S-transferase, GST, and glutathione peroxidase, GPx) were not affected by pure MCs). Crude extract of the laboratory culture of cyanobacteria Microcystis aeruginosa (containing 300 μg/L of MCs) had no effects on algal growth or any of the biomarkers. Weak growth stimulations after 4-7 days were observed after exposures to the growth-spent medium of the M. aeruginosa culture, which also inhibited activities of GST after prolonged exposures. Other investigated parameters (reduced GSH and activity of GPx) were not affected by any of the cyanobacterial samples. The results were compared with effects of model oxidative stressor herbicide paraquat, which exhibited variable effects on both algal growth and biomarkers (decrease in reduced GSH, stimulations of GR). Taken together, although pure MCs induce oxidative stress in green alga, the effects of cyanobacterial mixtures, which are more relevant to the natural situation, are more complex and they differ from the pure toxin. High variability in the biochemical responses to the oxidative stress makes the interpretation of results complicated, which limits the use of these biomarkers as early warnings of toxicity under natural conditions.

• MeSH
• bakteriální toxiny toxicita   MeSH
• chemické látky znečišťující vodu toxicita   MeSH
• Chlorophyta účinky léků   mikrobiologie   fyziologie   MeSH
• glutathion metabolismus   MeSH
• glutathionperoxidasa metabolismus   MeSH
• glutathionreduktasa metabolismus   MeSH
• glutathiontransferasa metabolismus   MeSH
• herbicidy toxicita   MeSH
• látky reagující s kyselinou thiobarbiturovou metabolismus   MeSH
• Microcystis metabolismus   MeSH
• mikrocystiny metabolismus   toxicita   MeSH
• mořské toxiny toxicita   MeSH
• oxidační stres účinky léků   fyziologie   MeSH
• paraquat toxicita   MeSH
• sinice patogenita   MeSH
• toxiny kmene Cyanobacteria MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• bakteriální toxiny MeSH
• chemické látky znečišťující vodu MeSH
• glutathion MeSH
• glutathionperoxidasa MeSH
• glutathionreduktasa MeSH
• glutathiontransferasa MeSH
• herbicidy MeSH
• látky reagující s kyselinou thiobarbiturovou MeSH
• mikrocystiny MeSH
• mořské toxiny MeSH
• paraquat MeSH
• toxiny kmene Cyanobacteria MeSH

Wild birds are continually exposed to many anthropogenic and natural stressors in their habitats. Over the last decades, mass mortalities of wild birds constitute a serious problem and may possibly have more causations such as natural toxins including cyanotoxins, parasitic diseases, industrial chemicals and other anthropogenic contaminants. This study brings new knowledge on the effects of controlled exposure to multiple stressors in birds. The aim was to test the hypothesis that influence of cyanobacterial biomass, lead and antigenic load may combine to enhance the effects on birds, including modulation of antioxidative and detoxification responses. Eight treatment groups of model species Japanese quail (Coturnix coturnix japonica) were exposed to various combinations of these stressors. The parameters of detoxification and oxidative stress were studied in liver and heart after 30 days of exposure. The antioxidative enzymatic defense in birds seems to be activated quite efficiently, which was documented by the elevated levels and activities of antioxidative and detoxification compounds and by the low incidence of damage to lipid membranes. The greatest modulations of glutathione level and activities of glutathione-S-transferase, glutathione peroxidase, glutathione reductase, superoxide dismutase, catalase and lipid peroxidation were shown mostly in the groups with combined multiple exposures. The results indicate that the antioxidative system plays an important role in the protective response of the tissues to applied stressors and that its greater induction helps to protect the birds from more serious damage. Most significant changes of these "defense" parameters in case of multiple stressors suggest activation of this universal mechanism in situation with complex exposure and its crucial role in protection of the bird health in the environment.

• MeSH
• bakteriální toxiny farmakologie   MeSH
• biologické markery analýza   MeSH
• Coturnix metabolismus   virologie   MeSH
• glutathion metabolismus   MeSH
• glutathionperoxidasa metabolismus   MeSH
• glutathionreduktasa metabolismus   MeSH
• glutathiontransferasa metabolismus   MeSH
• játra účinky léků   metabolismus   MeSH
• katalasa metabolismus   MeSH
• látky reagující s kyselinou thiobarbiturovou metabolismus   MeSH
• mikrocystiny farmakologie   MeSH
• mořské toxiny farmakologie   MeSH
• newcastleská nemoc patofyziologie   MeSH
• olovo farmakologie   MeSH
• oxidační stres * MeSH
• peroxidace lipidů MeSH
• sinice chemie   patogenita   MeSH
• srdce účinky léků   MeSH
• superoxiddismutasa metabolismus   MeSH
• toxiny kmene Cyanobacteria MeSH
• virus newcastleské nemoci patogenita   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• bakteriální toxiny MeSH
• biologické markery MeSH
• glutathion MeSH
• glutathionperoxidasa MeSH
• glutathionreduktasa MeSH
• glutathiontransferasa MeSH
• katalasa MeSH
• látky reagující s kyselinou thiobarbiturovou MeSH
• mikrocystiny MeSH
• mořské toxiny MeSH
• olovo MeSH
• superoxiddismutasa MeSH
• toxiny kmene Cyanobacteria MeSH

Under environmental conditions, wild birds can be exposed to multiple stressors including natural toxins, anthropogenic pollutants and infectious agents at the same time. This experimental study was successful in testing the hypothesis that adverse effects of cyanotoxins, heavy metals and a non-pathogenic immunological challenge combine to enhance avian toxicity. Mortality occurred in combined exposures to naturally occurring cyanobacterial biomass and lead shots, lead shots and Newcastle vaccination as well as in single lead shot exposure. Mostly acute effects around day 10 were observed. On day 30 of exposure, there were no differences in the liver accumulation of lead in single and combined exposure groups. Interestingly, liver microcystin levels were elevated in birds co-exposed to cyanobacterial biomass together with lead or lead and the Newcastle virus. Significant differences in body weights between all Pb-exposed and Pb-non-exposed birds were found on days 10 and 20. Single exposure to cyanobacterial biomass resulted in hepatic vacuolar dystrophy, whereas co-exposure with lead led to more severe granular dystrophy. Haematological changes were associated with lead exposure, in particular. Biochemical analysis revealed a decrease in glucose and an increase in lactate dehydrogenase in single and combined cyanobacterial and lead exposures, which also showed a decreased antibody response to vaccination. The combined exposure of experimental birds to sub-lethal doses of individual stressors is ecologically realistic. It brings together new pieces of knowledge on avian health. In light of this study, investigators of wild bird die-offs should be circumspect when evaluating findings of low concentrations of contaminants that would not result in mortality on a separate basis. As such it has implications for wildlife biologists, veterinarians and conservationists of avian biodiversity.

• MeSH
• biomasa MeSH
• Coturnix metabolismus   mikrobiologie   MeSH
• játra metabolismus   patologie   virologie   MeSH
• látky znečišťující životní prostředí krev   MeSH
• mikrocystiny metabolismus   MeSH
• náchylnost k nemoci epidemiologie   MeSH
• nemoci ptáků krev   epidemiologie   etiologie   MeSH
• newcastleská nemoc krev   mikrobiologie   mortalita   MeSH
• olovo krev   MeSH
• sinice patogenita   MeSH
• vystavení vlivu životního prostředí analýza   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• látky znečišťující životní prostředí MeSH
• mikrocystiny MeSH
• olovo MeSH

Toxicity endpoints (nonspecific cytotoxicity, hepatotoxicity, neurotoxicity, immunotoxicity, and mutagenicity) were studied in cyanobacterial mats obtained from a shallow river. Some of the cyanobacterial mats tested were known to be non-geosmin producers, while others were geosmin-producers. No microcystin-like compounds were detected by HPLC in any of the biofilm samples. The mutagenicity and neurotoxicity of biofilm metabolites was negligible, and generally weak adverse effects of biofilm extracts detected in a battery of in-vitro assays indicated relatively low human health risks associated with biofilm toxicity. While the toxicity responses detected in the studied biofilms were weak, effects were not related to production of geosmin. It was therefore concluded that the production of this metabolite cannot be taken as an indication per se of the existence of a health hazard.

• MeSH
• biofilmy MeSH
• hepatocelulární karcinom patologie   MeSH
• hodnocení rizik MeSH
• lymfom patologie   MeSH
• myši MeSH
• nádorové buňky kultivované MeSH
• nádory jater patologie   MeSH
• naftoly toxicita   MeSH
• neuroblastom patologie   MeSH
• oxidační stres MeSH
• řeky MeSH
• sinice chemie   patogenita   MeSH
• testy genotoxicity MeSH
• testy toxicity MeSH
• vysokoúčinná kapalinová chromatografie MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• geosmin MeSH Prohlížeč
• naftoly MeSH