The Iguaçu River, located at the Southern part of Brazil, has a great socioeconomic and environmental importance due to its high endemic fish fauna and its potential to generate hydroelectric power. ...However, Iguaçu River suffers intense discharge of pollutants in the origin of the river. In a previous report, the local environmental agency described water quality to improve along the river course. However, no study with integrated evaluation of chemical analysis and biological responses has been reported so far for the Iguaçu River. In the current study, three different Brazilian fish species (
Astyanax bifasciatus
,
Chrenicicla iguassuensis
, and
Geophagus brasiliensis
) were captured in the five cascading reservoirs of Iguaçu River for a multi-biomarker study. Chemical analysis in water, sediment, and muscle indicated high levels of bioavailable metals in all reservoirs. Polycyclic aromatic hydrocarbons (PAHs) were detected in the bile of the three fish species. Integration of the data through a FA/PCA analysis demonstrated the poorest environmental quality of the reservoir farthest from river’s source, which is the opposite of what has been reported by the environmental agency. The presence of hazardous chemicals in the five reservoirs of Iguaçu River, their bioaccumulation in the muscle of fish, and the biological responses showed the impacts of human activities to this area and did not confirm a gradient of pollution between the five reservoirs, from the source toward Iguaçu River’s mouth. Therefore, diffuse source of pollutants present along the river course are increasing the risk of exposure to biota and human populations.
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CEKLJ, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Risk assessment studies on aquatic pollution, a threat to water quality and aquatic biota, often rely on animal capture and experimentation. However, ethical concerns surrounding animal use have ...prompted the development and use of alternative methods. This study investigates the viability of primary hepatocyte cultures from
Oreochromis niloticus
as an in vitro tool for environmental contaminant screening, focusing on cadmium as a pollutant model. Isolated hepatocytes were cultured on plates using a mixture of supplemented L15/F12 media. Freezing conditions were tested for cell stock preservation. The cultured hepatocytes were exposed to 0.5, 5, and 50 µM of cadmium to assess cell viability, reactive oxygen and nitrogen species, and antioxidant molecules. Results demonstrated a concentration and time-dependent decrease in cell viability upon cadmium exposure. Cadmium exposure also induced an imbalance in the antioxidant defense system, leading to increased reactive oxygen species levels and lipid peroxidation. These findings validate the cadmium toxicity to primary hepatocytes and confirm the applicability of commonly used biomarkers in animal-based ecotoxicology and risk assessment studies. The replication of these biomarkers in primary hepatocyte cultures provides an ethical alternative to reduce animal testing in ecotoxicology. Lastly, the study highlights the potential of primary hepatocyte cultures as an in vitro tool for evaluating the toxicity of environmental contaminants and supports the integration of this tool in future environmental risk assessment studies, promoting sustainable water resource management while reducing reliance on animal experimentation.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
This study investigated the effects of different doses of 17-β-estradiol (E
2) in
Rhamdia quelen. Groups of males exposed to different doses of E
2 (0.1
mg
kg
−
1, 1
mg
kg
−
1 and 10
mg
kg
−
1) were ...compared with non-exposed male and female fish groups. Among the considered biomarkers, no significant differences were observed for micronuclei test, reduced glutathione concentration and lipid peroxidation. All E
2-treated individuals had decreased glutathione
S-transferase activity. Increased catalase and superoxide dismutase activities, increased vitellogenin expression and decreased metallothionein concentration were observed in males treated with the highest dose. Liver of all test groups showed necrotic areas, but cytoplasm vacuolization was again found only in the individuals exposed to highest dose. E
2 causes deleterious hepatic effects to
R. quelen, and vitellogenin expression, catalase and superoxide dismutase activity and metallothionein concentration represent appropriate biomarkers for studying E
2 effects. Additionally, the response of some biomarkers was similar in males exposed to E
2 and unexposed females, and therefore exposure to endocrine disruptors may cause consequences for fish populations.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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•Nutritional assessment of Ca, Mg, K, P, Cu, Mn, Fe, Zn, Cd, Cr, and Pb in potato.•Higher metal concentrations in potato peels than in the pulp.•Higher bioacessibility of Ca, Mg, P ...and K and lower of Cu, Zn and Fe.•Relevant fractions of P, Mn, Zn, and Fe from potatoes were absorbed by Caco-2 cells.•Potatoes analyzed did not present a health risk and good nutritional contribution.
Among the most consumed foods in the world is potato, which occupies the first place as a non-grain commodity, demonstrating the importance of its assessment concerning the population's food safety. In this study, the nutrients Ca, Mg, K, P, Cu, Mn, Fe, and Zn and the potentially toxic trace elements Cd, Cr, and Pb were evaluated considering their total contents, bioaccessible and bioavailable fractions in different potato cultivars, in an unpublished approach in the literature. The in vitro standard gastrointestinal digestion method (INFOGEST) and a model of the intestinal epithelial barrier using the Caco-2 cell line were applied for investigate the presence of metals in potato. For the macroelements, the bioaccessibility (% w/w) varied in the ranges: K (57–72 %), P (59–76 %), Mg (83–103 %), and Ca (30–123 %), whereas for the microelements were: Cu (27–74 %) and Mn (4.22–12.02, 60–119 %). The potentially of trace toxic elements, Cd and Pb, were found in 75 % of the samples, however, all the concentration values were below the maximum levels allowed of 0.10 µg/g. Chromium was determined only in potato peels and has no maximum established level. The bioaccessible and bioavailable fractions of Cd, Cr, and Pb were below the limits of quantification of the spectrometric methods (LOQ − µg/L: 0.063 Cd, 0.65 Cr, and 0.44 Pb). The potato samples were considered safe for consumption regarding the presence of potentially toxic trace elements, with a remarkable nutritional contribution.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Highlights ▸ We investigated cadmium effects in the early stages of chick embryos. ▸ Changes in morphology and antioxidant enzymatic activities were analyzed. ▸ Cadmium exposure showed morphological ...abnormalities, mainly in the cephalic region. ▸ Cadmium can be a powerful teratogenic to chick embryos.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Here, we examined the impact of dichlorodiphenyltrichloroethane (DDT) and monomethyl mercury (MeHg) on the redox milieu and survival of hepatocytes from
Hoplias malabaricus (
traíra). After isolation ...and attachment of cells, we established one control and four treatments: DDT (50
nM of DDT), MeHg I (0.25
μM of MeHg), MeHg II (2.5
μM of MeHg) and DDT
*
MeHg I (combination of 50
nM of DDT and 0.25
μM of MeHg). After four days the exposed hepatocytes presented significantly increased damage in lipids (all treatments), proteins (DDT
*
MeHg I and MeHg II) and reduced cell viability (all treatments). Also the antioxidant enzymes catalase, glucose-6-phosphate dehydrogenase (G6PDH), glutathione reductase and superoxide dismutase were affected. The current data showed that despite of some protective responses, the increased disturbs on membrane lipids and proteins, increased hydrogen peroxide levels, and decreased glutathione concentration and cell viability strongly indicate oxidative stress as the reason of hepatotoxicity due to DDT and MeHg exposure. In addition, DDT and MeHg together had greater effect than alone when G6PDH and glutathione-
S-transferase activities and lipids damage were considered. These findings are indicative of hepatotoxicity occurring at realistic concentrations of DDT and MeHg found in Amazonian fish tissues.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
The recent increase of freshwater eutrophication has favored cyanobacteria blooms and consequently the increase of toxins such as microcystin-LR in aquatic environments, but few is know about the ...associated effect of toxin and other compounds. Pyriproxyfen is an insecticide indicated by WHO (World Health Organization) to control Aedes aegypti mosquito (vector of Dengue, Chikungunya and Zika diseases), however, the effects are not well described to non-target species, such as fish. The early life stages (ELS) of fish are more sensitive to chemical stress due to higher metabolic rate, immature immune system and high superficial area/volume ratio. In the current study, ELS of R. quelen a Neotropical fish were exposed to environmentally realistic concentrations of microcystin (1, 10 and 100 µg L−1; M1, M2 and M3 groups, respectively) from an algal extract, pyriproxyfen (1 and 10 µg L−1, P1 and P2) and their association (co-exposure). The hatching, survival and larvae deformities were analyzed, and applied a mathematical model to evaluate the effects on the population size along further generations. Both compounds were toxic to embryos/larvae of fish, but the effects were more pronounced in M2, P1M2 and P2M1 for hatching and M2, P1M2, P2M1 and P1 for survival. Deformities prevailed in groups exposed to the chemicals at 48 hpf (hours post-fertilization) were suggestions of toxicological interaction in P1M2, P2M1 and P2M2 at 48 and 72 hpf. In 96 hpf, the levels of deformities were lower than in previous times. Model predicted population density over 100 years decreased to lower than 0.5 (50%) in all groups, except for P1M1, indicating risk of extinction. P1M2 had the worse results, followed by M2, P1M3 and P2M1. Cyanobacterial blooms can lead to microcystin-LR levels higher than M2 (10 µg L−1), and the suggestion of toxicological interaction with pyriproxyfen is relevant because both compounds may potentially coexist in aquatic environments. Finally, mathematical models may provide an ecological interpretation of the risk of exposure of fish.
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•Embryos of R. quelen fish were exposed to the cyanotoxin microcystin and insecticide pyriproxyfen.•Effects on the hatching and survival of embryos and larvae occurred.•Morphological deformities were more frequent at the first 72 h of development.•Mathematical modelling revealed a risk of extinction to the species R. quelen.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Hepatocytes were isolated and cultured from Hoplias malabaricus using a non‐enzymatic protocol. From 6·9 to 9·4 × 107 hepatocytes g−1 of liver were isolated and cell viability was 65–85%. Fish ...hepatocytes attached well to untreated polystyrene flasks (Corning) as well as on treated surfaces with extracellular matrix proteins, i.e. fibronectin, matrigel or type I collagen coatings. Cells rapidly started migrating and reorganizing in cord‐like groups after seeding, with spaces similar to bile canaliculi in vivo. Prominent nucleolus and euchromatin‐rich rounded nucleus, abundant mitochondria, well‐developed rough endoplasmic reticulum, polysomes and Golgi apparatus were seen under ultrastructural analysis. Cells remained functional and metabolically active after 6 days in culture. The protocol established in the current work provides the basis for further studies of native fishes for accurate in vitro toxicological studies.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Cylindrospermopsin (CYN) is a cyanotoxin that is cytotoxic to a wide variety of cells, particularly to the hepatocytes. In this study, the toxic effects of purified CYN were investigated in primary ...cultured hepatocytes of Neotropical fish
Hoplias malabaricus
. After isolation, attachment, and recovery for 72 h, the cells were exposed for 72 h to 0, 0.1, 1.0, 10, and 100 μg l
−1
of CYN. Then, cell viability and a set of oxidative stress biomarker responses were determined. Catalase, superoxide dismutase, glucose-6-phosphate dehydrogenase, and glutathione
S
-transferase activities were not affected by exposure to CYN. Concentration-dependent decrease of glutathione reductase activity occurred for most CYN-exposed groups, whereas non-protein thiol content increased only for the highest CYN concentration. Lipid peroxidation, protein carbonylation, and DNA damage levels were not altered, but reactive oxygen species levels increased in the cells exposed to the highest concentration of CYN. Cell viability decreased in all the groups exposed to CYN. Thus, CYN may cause a slight change in redox balance, but it is not the main cause of cell death in
H. malabaricus
hepatocytes.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
► Hepatocytes from Neotropical fish Prochilodus lineatus were isolated with dispase. ► Cyanotoxin cylindrospermopsin CYN reduced hepatocytes viability at low concentrations. ► Multixenobiotic ...resistance mechanism (MXR) was impaired by CYN. ► CYN increased ROS production and lipid peroxidation in hepatocytes. ► Protein and DNA damages as well as GSH/GSSG ratio were not involved in CYN toxicity.
Cylindrospermopsin is a potent toxicant for eukaryotic cells produced by several cyanobacteria. Recently, primary hepatocyte cultures of Neotropical fish have been established, demonstrating to be a quite efficient in vitro model for cellular toxicology studies. In the current study, a protocol for culture of Prochilodus lineatus hepatocytes was established and utilized to investigate the cellular responses to purified cylindrospermopsin exposure. Hepatocytes were successfully dissociated with dispase, resulting in a cell yield of 6.36×107cellsg−1 of liver, viability of 97% and attachment on uncoated culture flasks. For investigation of cylindrospermopsin effects, hepatocytes were dissociated, cultured during 96h and exposed to three concentrations of the toxin (0.1, 1.0 or 10μgl−1) for 72h. Cylindrospermopsin exposure significantly decreased cell viability (0.1 and 1μgl−1) and multixenobiotic resistance mechanism, MXR (all exposed groups), but increased reactive oxygen/nitrogen species levels (all exposed groups) and lipid peroxidation (10μgl−1). On the other hand no significant alterations were observed for other biochemical biomarkers as 2GSH/GSSG ratio, protein carbonyl levels and DNA strand breaks or glutathione S-transferase and glucose 6-phosphate dehydrogenase activities. In conclusion, hepatocytes might be made sensitive to cylindrospermopsin, at least in part, due to reduction of xenobiotics and endobiotics efflux capacity by MXR. Additionally, the toxin exposure suggests important issues regarding hepatocytes survival at the lowest cylindrospermopsin concentrations.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
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