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1.
Sci Total Environ ; 924: 171680, 2024 May 10.
Article En | MEDLINE | ID: mdl-38479529

The 2,4-Dichlorophenoxyacetic acid (2,4-D) is a low-cost herbicide to eradicate broadleaf weeds. Since the development of 2,4-D resistant transgenic crops, it has been described as one of the most widely distributed pollutants in the world, increasing concern about its environmental impacts. This study aimed to elucidate the antioxidant system response in animals exposed to 2,4-D by different routes of exposure. It focused on determining if tissue, phylogenetic group, and herbicide formulation would influence the antioxidant mechanisms. A careful literature search of Scopus, WoS, and Science Direct retrieved 6983, 24,098, and 20,616 articles, respectively. The dataset comprised 390 control-treatment comparisons and included three routes of exposure: transgenerational, oral, and topical. The data set for transgenerational and oral exposure revealed oxidative stress through a decrease in enzymatic activities and the level of molecules of the antioxidant system. In contrast, topical exposure increased the oxidative stress. Tissue-specific analyses revealed that the transgenerational effects reduced hepatic catalase (CAT) activity. Oral exposure caused a variety of effects, including increased CAT activity in the prostate and decreased activity in various tissues. Mammals predominate in the transgenerational and oral groups, showing a significantly reduced activity of the antioxidant system. In contrast, in the topical exposure, an increased activity of oxidative stress biomarkers was observed in fish, earthworms, and mollusks. The effects of the 2,4-D formulation on oxidative stress responses showed significant differences between pure and commercial formulations, with oral exposure resulting in decreased activity and topical exposure increasing responses. In summary, orally exposed animals exhibited a clear decrease in enzyme activities, transgenerational exposure elicited tissue-specific prompted biochemical reductions, and topical exposure induced increased responses, emphasizing the need for unbiased exploration of the effects of 2,4-D on biomarkers of oxidative stress while addressing publication bias in oral and topical datasets.


Antioxidants , Herbicides , Animals , Male , Antioxidants/metabolism , Herbicides/pharmacology , Phylogeny , Oxidative Stress , Biomarkers/metabolism , 2,4-Dichlorophenoxyacetic Acid/toxicity , Catalase/metabolism , Superoxide Dismutase/metabolism , Glutathione Transferase/metabolism , Mammals/metabolism
2.
Environ Sci Pollut Res Int ; 30(16): 47366-47380, 2023 Apr.
Article En | MEDLINE | ID: mdl-36738412

Pesticides use increased worldwide with a record in Brazil. Although several works addressed the effects of pesticides on living organisms, only a few considered their mixture, and even fewer tried to unravel their role in tumoral progression. Due to the relevance of cancer, in the present study, the effects of the mixture of pesticides widely used in Brazil (Glyphosate, 2,4-dichlorophenoxyacetic acid, Mancozeb, Atrazine, Acephate, and Paraquat) and their main metabolites (Aminomethylphosphonic Acid, 2,4-diclorophenol, Ethylenethiourea, Desethylatrazine, Methamidophos, and Paraquat) were investigated on the malignancy phenotype of murine melanoma B16-F1 cells after acute (24 h) and chronic (15 days) exposures. The tested concentrations were based on the Acceptable Daily Intake (ADI) value established by Brazilian legislation. The set of results showed that these chemicals modulate important parameters of tumor progression, affecting the expression of genes related to tumor aggressiveness (Mmp14 and Cd44) and multidrug resistance (Abcb1, Abcc1, and Abcc4), as well as tissue inhibitors of metalloproteinases (Timp1, Timp2, and Timp3). These findings revealed an absence of cytotoxicity but showed modulation of migration, invasion, and colonization capacity of B16-F1 cells. Together, the results point to some negative ways that exposure to pesticides can affect the progression of melanoma and raise a concern related to the increasing trend in pesticide use in Brazil, as the country is one of the major world food suppliers.


Melanoma , Pesticides , Animals , Mice , Pesticides/toxicity , Paraquat , Phenotype , Complex Mixtures
3.
Ecotoxicology ; 32(1): 12-24, 2023 Jan.
Article En | MEDLINE | ID: mdl-36547786

Aquatic biota is increasingly being exposed to chemical pollutants due to human activities and the relationship between the level of environmental pollution and fish reproduction is a continuously ongoing issue. The vitellogenin (Vtg) protein synthesis can be induced in the liver of juvenile and male fish after stimulation of the estrogen receptor and therefore, Vtg has been used as a biomarker of xenoestrogen exposure in several fish species. The current study reported the first physicochemical characterization of Vtg from Oreochromis niloticus. Adult male fish were exposed to 17α-ethinylestradiol for Vtg induction. Purified vitellogenin from plasma showed low stability at 25 and 4 °C in saline conditions, and good stability in acidic (low pH) or in heated conditions. The 3D modeling provided useful information on the structure of O. niloticus Vtg showing conserved structural features. According to bioinformatics and experimental results, there are important structural differences between the two chemical forms of Vtg (VtgAb and VtgC) in a phylogenetic context. The present results add information about the development of ecotoxicological immunoassays to study the endocrine disruption in O. niloticus improving the Vtg performance as a biomarker of reproduction in fish.


Cichlids , Water Pollutants, Chemical , Animals , Male , Biomarkers/metabolism , Ethinyl Estradiol/toxicity , Phylogeny , Vitellogenins/metabolism , Water Pollutants, Chemical/analysis , Fish Proteins
4.
Environ Toxicol Pharmacol ; 97: 104034, 2023 Jan.
Article En | MEDLINE | ID: mdl-36496183

PBDEs are toxic, lipophilic, hydrophobic, and persistent artificial chemicals, characterized by high physical and chemical stability. Although PBDEs are known to disturb hormone signaling, many effects of 2,2',4,4',5 - pentain polybrominated diphenyl ethers (BDE-99) in fish remain unclear. The current study investigates the effects of BDE-99 in Oreochromis niloticus where sixty-four juvenile fish were orally exposed to 0.294, 2.94, 29.4 ng g-1 of BDE-99, every 10 days, during 80 days. The results showed histopathological findings in liver and kidney, increasing acetylcholinesterase activity in muscle, disturbs in the antioxidant system in liver and brain and decreasing the plasmatic levels of vitellogenin in females. According to multivariate analysis (IBR), the higher doses are related to the interaction of oxidative and non-oxidative enzymes. The present study provided evidence of deleterious effects after sub-chronic exposure of BDE 99 to O. niloticus, increasing the knowledge about its risk of exposure in fish.


Cichlids , Flame Retardants , Polybrominated Biphenyls , Animals , Female , Halogenated Diphenyl Ethers/toxicity , Acetylcholinesterase , Flame Retardants/toxicity
5.
Mar Pollut Bull ; 181: 113828, 2022 Aug.
Article En | MEDLINE | ID: mdl-35716493

Although the simplification of multivariate histopathological data into univariate indices can be useful for the assessment of environmental quality, this implies a great loss of information. The objective of the present study was to evaluate the effectiveness, in the context of environmental quality assessment, of an approach that integrates individual histopathological responses in a discriminated manner with the results of contaminants by means of multivariate analyses. This analysis was compared to the diagnosis of environmental quality provided by the use of the univariate Bernet histopathological index. Contaminant loads (sediments and fish) and the liver histopathology of Cathorops spixii were integrated through multivariate analysis. Integrated individual histopathological responses allowed classifying environmental quality from more to less impacted sites, while the univariate index showed some inconsistencies with chemical loads and allowed identifying only the most impacted site.


Catfishes , Water Pollutants, Chemical , Animals , Biomarkers , Environmental Monitoring/methods , Geologic Sediments , Liver/chemistry , Water Pollutants, Chemical/analysis
6.
Environ Monit Assess ; 194(7): 497, 2022 Jun 13.
Article En | MEDLINE | ID: mdl-35695983

Chronic exposure to multiple pollutants affects aquatic organisms, even at low concentrations, and can impair fishery activities along marine coastlines. The bioavailability of toxic metals and the presence of metals and polycyclic aromatic hydrocarbons (PAHs) in both water and sediment can explain the worst-case scenario of fish health and fishery production decline along the Algeria coastline. The hepatosomatic index (HIS), gonadosomatic index (GSI), and condition factor (K) in the studied species from the Algiers, Bou Ismail, and Zemmouri bays are the first indicators of the poor environmental health along the studied region. These findings could be explained by the bioavailability of Zn, Cu, Cr, Mn, Hg, and Ni and the detection of PAHs in the water and sediment of these bays. Additionally, histopathological damage in the liver is described in sardine (Sardina pilchardus), anchovy (Engraulis encrasicolus), and sardinelle (Sardinella aurita) highlights the current study in the investigation of the risk of exposure to biota or human populations. The occurrence of permanent lesions in the livers of fish impairs organ function and increases the incidence of diseases affecting the fish community. Furthermore, the factor analysis with principal component analysis (FA/PCA) dataset explains the physiological disturbances described in all studied species. These findings revealed that Zemmouri bay is the most affected by chemicals, suggesting that S. pilchardus is the most sensitive species. Finally, the results showed that the bioavailability of chemicals present in the studied bays confirms poor water quality, which can explain the decrease in fishery production along the Algerian Coastline.


Polycyclic Aromatic Hydrocarbons , Water Pollutants, Chemical , Algeria , Animals , Bays , Environmental Monitoring/methods , Fisheries , Fishes , Mediterranean Sea , Polycyclic Aromatic Hydrocarbons/analysis , Polycyclic Aromatic Hydrocarbons/toxicity , Water Pollutants, Chemical/analysis , Water Pollutants, Chemical/toxicity
7.
Environ Sci Pollut Res Int ; 29(12): 17087-17102, 2022 Mar.
Article En | MEDLINE | ID: mdl-34655032

Flame retardants are compounds added to a high diversity of polymers used in electronics and furniture to decrease the risk of combustion. Decabromodiphenyl ether (BDE-209) is a polybrominated diphenyl ether (PBDE) congener still used worldwide, while 2, 4, 6-tribromophenol(TBP) is a PBDE metabolite used as a pesticide and flame retardant for wood conservation. These compounds have lipophilic properties and are easily bioaccumulated in the food chain. In the current study, the acute and chronic toxicity of BDE-209 and TBP was evaluated in Oreochromis niloticus through analyses of redox imbalance, neurotoxicity, and histopathological biomarkers after acute (24, 48, 72, and 96 h) and chronic (90 days) exposure to 0.5, 5, and 50 ng/g of the polybrominated compounds. The results showed effects on glutathione S-transferase(GST) activity and damage to biomolecules in both acute and chronic exposures. Liver histopathology and the ultrastructure of hepatocytes revealed alterations and damage in individuals from both experiments, but only BDE-209 led to neurotoxic effects. The current study revealed new endpoints related to polybrominated compounds in fish, highlighting the need to review the risk of exposure to biota.


Cichlids , Flame Retardants , Animals , Cichlids/metabolism , Flame Retardants/metabolism , Flame Retardants/toxicity , Halogenated Diphenyl Ethers/metabolism , Halogenated Diphenyl Ethers/toxicity , Humans , Liver
8.
Environ Sci Pollut Res Int ; 29(8): 11291-11303, 2022 Feb.
Article En | MEDLINE | ID: mdl-34535858

Cancer is one of the leading causes of mortality worldwide. Even with the advances of pharmaceutical industry and treatments, the mortality rate for various types of cancer remains high. In particular, phenotypic alterations of tumor cells concerning drug efflux, migratory and invasive capabilities may represent a hurdle for cancer treatment and contribute to poor prognosis. In the present study, we investigated the effects of polybrominated diphenyl ethers (PBDEs) used as flame retardants on phenotypic features of melanoma cells that are important for cancer. Murine melanoma B16-F1 (less metastatic) and B16-F10 (more metastatic) cells were exposed to 0.01-1.0 nM of BDE-47 (2,2',4,4'-tetrabromodiphenyl ether), BDE-99 (2,2',4,4',5-pentabromodiphenyl ether), and the mixture of both (at 0.01 nM) for 24 h (acute exposure) and 15 days (chronic exposure). The polybrominated diphenyl ethers (PBDEs) did not affect cell viability but led to increased drug efflux transporter activity, cell migration, and colony formation, as well as overexpression of Abcc2 (ATP-binding cassette subfamily C member 2), Mmp-2 (matrix metalloproteinase-2), Mmp-9 (matrix metalloproteinase-9), and Tp53 (tumor protein p53) genes and downregulation of Timp-3 (tissue inhibitor of metalloproteinase 3) gene in B16-F10 cells. These effects are consistent with increased aggressiveness and malignancy of tumors due to exposure to the flame retardants and raise some concerns on the effects such chemicals may have on melanoma treatment and cancer prognosis.


Flame Retardants , Melanoma , Polybrominated Biphenyls , Animals , Halogenated Diphenyl Ethers , Matrix Metalloproteinase 2 , Mice , Phenotype
9.
J Trace Elem Med Biol ; 68: 126854, 2021 Dec.
Article En | MEDLINE | ID: mdl-34488184

BACKGROUND: Silver nanoparticles (AgNP) are largely used in nanotechnological products, but the real risks for human and environment are still poorly understood if we consider the effects of mixtures of AgNP and environmental contaminants, such as non-essential metals. METHODS: The aim of the present study was to investigate the cytotoxicity and toxicological interaction of AgNP (1-4 nm, 0.36 and 3.6 µg mL-1) and cadmium (Cd, 1 and 10 µM) mixtures. The murine macrophage cell line RAW 264.7 was used as a model. RESULTS: Effects were observed after a few hours (4 h) on reactive oxygen species (ROS) and became more pronounced after 24 h-exposure. Cell death occurred by apoptosis, and loss of cell viability (24 h-exposure) was preceded by increases of ROS levels and DNA repair foci, but not of NO levels. Co-exposure potentiated some effects (decrease of cell viability and increase of ROS and NO levels), indicating toxicological interaction. CONCLUSION: These effects are important findings that must be better investigated, since the interaction of Cd with AgNP from nanoproducts may impair the function of macrophages and represent a health risk for humans.


Metal Nanoparticles , Silver , Animals , Cadmium/toxicity , Cadmium Chloride , Cell Line , Cell Survival , Humans , Macrophages , Metal Nanoparticles/toxicity , Mice , Reactive Oxygen Species , Silver/toxicity
10.
Environ Toxicol Pharmacol ; 87: 103693, 2021 Oct.
Article En | MEDLINE | ID: mdl-34166789

Polybrominated diphenyl esters are emerging environmental contaminants with few toxicological data, being a concern for the scientific community. This study evaluated the effects of BDE-47 on the health of Oreochromis niloticus fish. The animals were exposed to three doses of BDE-47 (0, 0.253, 2.53, 25.3 ng g-1) every 10 days, for 80 days. The BDE-47 affected the hepatosomatic and gonadosomatic index in female and the condition factor by intermediate dose in both sexes. The levels of estradiol decreased and the T4 are increased, but the vitellogenin production was not modulated in male individuals. Changes in AChE, GST, LPO and histopathology were observed while the integrated biomarker response index suggests that the lowest dose of BDE-47 compromised the activity of antioxidant enzymes. The oral exposure to BDE-47 in environmental concentrations is toxic to O. niloticus and the use of multiple biomarkers is an attribution in ecotoxicology studies and biomonitoring programs.


Cichlids , Halogenated Diphenyl Ethers/toxicity , Water Pollutants, Chemical/toxicity , Acetylcholinesterase/metabolism , Administration, Oral , Animals , Biomarkers/blood , Biomarkers/metabolism , Brain/drug effects , Brain/metabolism , Cichlids/blood , Cichlids/metabolism , Estradiol/blood , Female , Glutathione Transferase/metabolism , Gonads/drug effects , Kidney/drug effects , Kidney/pathology , Liver/drug effects , Liver/pathology , Male , Muscles/drug effects , Muscles/metabolism , Thyrotropin/blood , Thyroxine/blood , Vitellogenins/blood
11.
Environ Toxicol Pharmacol ; 87: 103682, 2021 Oct.
Article En | MEDLINE | ID: mdl-34102321

Urban sewage is a source of major contamination in aquatic systems and contributes to environmental and human health disturbances. This study investigates the effects of sewage-polluted waters from Iguaçu River on the health of juvenile Oreochromis niloticus. Two hundred four specimens were exposed to riverine water in four groups: no diluted, 25 and 50 % diluted water and a control group without tested water for 72 days. Biological samples were obtained for histopathological, neurotoxicity, antioxidant defenses, genotoxicity, metallothionines expression and polycyclic aromatic hydrocarbons (PAHs) metabolites. The results showed histopathological alterations in liver and gills, genotoxic alteration in erythrocytes, reduction of acetylcholinesterase activity in brain and muscle, activation of antioxidant defenses in the liver, recruitment of metals by metallothionein and the detection of PAHs metabolites in bile. These results demonstrate that juveniles of O. niloticus are susceptible to Iguaçu River exposure water and they can be used as indicator of water quality.


Cichlids , Water Pollutants, Chemical/toxicity , Acetylcholinesterase/metabolism , Animals , Brain/drug effects , Brain/metabolism , Brazil , Catalase/metabolism , Cichlids/genetics , Cichlids/metabolism , DNA Damage , Glutathione/metabolism , Glutathione Transferase/metabolism , Hydrocarbons, Chlorinated/analysis , Hydrocarbons, Chlorinated/toxicity , Kidney/drug effects , Kidney/metabolism , Liver/drug effects , Liver/metabolism , Liver/pathology , Metallothionein/metabolism , Metals/analysis , Metals/toxicity , Muscles/drug effects , Muscles/metabolism , Pesticides/analysis , Pesticides/toxicity , Polycyclic Aromatic Hydrocarbons/analysis , Polycyclic Aromatic Hydrocarbons/toxicity , Rivers , Water Pollutants, Chemical/analysis
12.
Chemosphere ; 277: 130199, 2021 Aug.
Article En | MEDLINE | ID: mdl-33770691

Toxic metals and silver nanoparticles (AgNPs) are of great importance as pollutants and their frequent use increases the risk of exposure to biota, but few studies have described co-toxic effects in aquatic organisms. In fish, the method using early stages of development are interesting parameters to validate ecotoxicological studies, and more recently, the use of mathematical models has substantially increased the efficiency of the method. Post hatching stages of native catfish Rhamdia quelen were exposed to single or combined mixtures of toxic metals (Mn, Pb, Hg or AgNPs) in order to study its effects. Fertilized eggs were exposed for 24, 48, 72, and 96 h, where hatching and survival rates, malformation frequency, and neuromast structure damages were evaluated. The results showed alterations in hatching rate after single and combined exposure to metals, but mixtures showed effects more severe comparatively with the single exposures. A similar result including a time-dependent effect was observed in survival rates and incidence of deformities. Overall, embryos and larvae were sensitive to toxic metals exposure while the mathematical modeling suggested a population reduction size including risk of local extinction.


Catfishes , Metal Nanoparticles , Water Pollutants, Chemical , Animals , Ecotoxicology , Larva , Metal Nanoparticles/toxicity , Silver , Water Pollutants, Chemical/toxicity
13.
Environ Toxicol Pharmacol ; 83: 103596, 2021 Apr.
Article En | MEDLINE | ID: mdl-33482285

The wastewater contamination of urban rivers is a concern for biodiversity and a consequence from poor urban conservation policies. In the current study, the impact of urban and industrial activities was investigated in Iguaçu river (Southern Brazil) using juvenile Oreochromis niloticus, after trophic and chronic exposure (25, 50 and 100 %), over 81 days. After exposure liver, gills, gonads, brain, muscle, and blood were sampled for chemical, biochemical, histopathological, genotoxic and molecular analyses. Water levels of persistent organic pollutants such as polychlorinated biphenyls, organochlorine pesticides, polycyclic aromatics hydrocarbon (PAHs) and metals were investigated. The redox unbalance, histopathological and increase in vitellogenin expression in fish revealed both the bioavailability of micropollutants and their harmful effects. According to the results, the level of Iguaçu river pollution negatively impacts the health of O. niloticus revealing and highlighting the risk of this pollution exposure to biota and human populations.


Cichlids , Water Pollutants, Chemical/toxicity , Acetylcholinesterase/metabolism , Animals , Brain/drug effects , Brain/metabolism , Brazil , Catalase/metabolism , Cichlids/blood , Cichlids/metabolism , Female , Gills/drug effects , Gills/pathology , Glutathione Transferase/metabolism , Gonads/drug effects , Gonads/pathology , Hydrocarbons, Chlorinated/analysis , Hydrocarbons, Chlorinated/toxicity , Liver/drug effects , Liver/metabolism , Liver/pathology , Male , Metals, Heavy/analysis , Metals, Heavy/toxicity , Muscles/drug effects , Muscles/metabolism , Polycyclic Aromatic Hydrocarbons/analysis , Polycyclic Aromatic Hydrocarbons/toxicity , Protein Carbonylation/drug effects , Rivers , Vitellogenins/blood , Water Pollutants, Chemical/analysis
14.
Environ Sci Pollut Res Int ; 28(8): 9517-9528, 2021 Feb.
Article En | MEDLINE | ID: mdl-33146826

The diversity of aquatic ecosystems impacted by toxic metals is widely distributed throughout the world. The application of metallothionein (MT) as an early warning sign of metal exposure in freshwater fish is important in biomonitoring, but a more accessible, sensitive, safe, and efficient new methodological strategy is necessary. On this way, a fish MT synthetic gene from Oreochromis aureos was expressed in Escherichia coli to produce polyclonal antibodies against the protein. In the validation assays, these antibodies were able to detect hepatic MT from freshwater fishes Oreochromis niloticus, Pimelodus maculatus, Prochilodus lineatus, and Salminus brasiliensis showing a potential tool for toxic metals biomarker in biomonitoring of aquatic ecosystems. The current results showed the applicability of this molecule in quantitative immunoassays as a sensor for monitoring aquatic environments impacted by toxic metals. Due to the lack of methods focusing on metal pollution diagnostics in aquatic ecosystems, the current proposal revealed a promising tool to applications in biomonitoring programs of water resources, mainly in Brazil where the mining activity is very developed.


Metallothionein , Water Pollutants, Chemical , Animals , Brazil , Ecosystem , Environmental Monitoring , Metallothionein/genetics , Water , Water Pollutants, Chemical/analysis
15.
Ecotoxicol Environ Saf ; 208: 111540, 2021 Jan 15.
Article En | MEDLINE | ID: mdl-33157514

The current study combined chemical data on trace elements and polycyclic aromatic hydrocarbons (PAH) from sediment and used a multibiomarker approach in the catfish Sciades herzbergii to evaluate two different sites in São Marcos Bay, Brazil. Higher diffuse contaminations by trace elements and PAH were detected in the sediment of Porto Grande (PG) harbor than in the Ilha dos Caranguejos (IC) reference area. A multibiomarker was used in catfish to evaluate the bioavailability of PAH in bile and the effects of pollutants in target tissues. The parameters considered were oxidative stress biomarkers (SOD, CAT, GSH, GST and LPO) and histopathological alterations and were compared between two seasons. The biological responses revealed adverse effects on the population, as indicated by the presence of trace elements and PAH as stressors. Principal component analysis (PCA) of the biomarkers corroborated these results and indicated that fish from the PG site during the rainy season in 2019 exhibited many biological effects compared to 2018. Overall, the present study showed that environmental contamination increased over the years and provides information on the contamination of sediments in the São Marcos Bay, Brazil. The results showed that the presence of contaminants was correlated with the health status of the catfish S. herzbergii.


Catfishes/physiology , Environmental Monitoring , Water Pollutants, Chemical/metabolism , Animals , Biomarkers , Brazil , Environmental Pollutants/analysis , Environmental Pollution/analysis , Geologic Sediments/analysis , Polycyclic Aromatic Hydrocarbons/analysis , Polycyclic Aromatic Hydrocarbons/metabolism , Seasons , Water Pollutants, Chemical/analysis
16.
J Mater Sci Mater Med ; 31(11): 95, 2020 Oct 31.
Article En | MEDLINE | ID: mdl-33128626

A promising use of bismuth nanoparticles (BiNPs) for different biomedical applications leads to a search for the elucidation of their toxicity mechanisms, since toxicity studies are still at early stage. In the current study, cytotoxic effects of BiNPs produced by laser ablation in solution (LASiS) was investigated in the murine macrophage line RAW 264.7. The cells were exposed to 0.01-50 µg ml-1 of BiNPs for 24 and 48 h and then cytotoxicity assays were performed. Decrease of MTT conversion to formazan and of cell attachment were observed with no effects on cell proliferation. No loss of membrane integrity or significant changes of ROS and RNS levels were observed in exposed cells. Foremost, increased phagocytic activity and DNA repair foci occurred for cells exposed to BiNPs. These effects are important findings that must be considered in the case of biomedical application of BiNPs, since inappropriate macrophages activation and inactivation may lead to immunotoxicity. Bismuth nanoparticles (BiNPs) produced by laser ablation in solution and stabilized with BSA decrease enzyme-dependent MTT conversion to formazan and increase phagocytic activity and DNA repair foci in murine macrophage line RAW 264.7 when exposed to 50 µg ml-1. These effects are findings that should be considered in the case of biomedical application of BiNPs, since inappropriate macrophages activation and inactivation may lead to immunotoxicity.


Bismuth/toxicity , Formazans/chemistry , Macrophages/drug effects , Metal Nanoparticles/chemistry , RAW 264.7 Cells/drug effects , Animals , Bismuth/chemistry , Cell Adhesion , Cell Cycle , Cell Proliferation , Cell Survival , DNA/drug effects , DNA Damage/drug effects , DNA Repair , Lasers , Macrophages/cytology , Mice , Phagocytosis , RAW 264.7 Cells/cytology , Reactive Oxygen Species , Tetrazolium Salts/chemistry , Thiazoles/chemistry
17.
Chemosphere ; 260: 127556, 2020 Dec.
Article En | MEDLINE | ID: mdl-32682134

Polybrominated diphenyl ethers (PBDEs) are brominated, persistent and bioaccumulative flame retardants widely used in the manufacture of plastic products. Decabromodiphenyl ether (BDE-209) is the most prevalent PBDE in the atmosphere and found in human blood, breast milk and umbilical cord. In vitro studies showed that BDE-209 interferes with murine melanoma cells (B16F10), modulating cell death rates, proliferation and migration, important events for cancer progression. In order to evaluate if BDE-209 modulates metastasis formation in murine models, C57BL/6 mice were exposed to BDE-209 (0.08, 0.8 and 8 µg/kg) via gavage (5-day intervals for 45 days) (9 doses in total). Then, mice were inoculated with melanoma cells (B16-F10) at caudal vein receiving 4 additional doses of BDE-209. At 20th day post-cell inoculation, blood, lung, liver, kidney and brain were sampled for hematological, biochemical and morphological analyses. The slightly higher levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in the blood and pro-oxidant state in the liver of BDE-exposed mice indicated liver damage. Although the in vivo approach is for metastasis formation in the lung, they were unexpectedly observed in non-target organs (liver, brain, kidney and gonads). The similarity test showed high proximity among individuals from the control and a dissimilarity index between the control and exposed groups. The present data corroborate the known hepatotoxicity of BDE-209 to mice (C57BL/6) and demonstrate for the first time the increase of metastatic dissemination of B16F10 cells in vivo due to previous and continuous BDE-209 exposure, revealing possible implications of this organic compound with melanoma malignancy related traits.


Halogenated Diphenyl Ethers/pharmacology , Melanoma/pathology , Mice, Inbred C57BL , Neoplasm Metastasis/pathology , Alanine Transaminase/blood , Animals , Aspartate Aminotransferases/blood , Disease Models, Animal , Dose-Response Relationship, Drug , Female , Flame Retardants/pharmacology , Halogenated Diphenyl Ethers/toxicity , Heterografts , Humans , Liver/drug effects , Liver/pathology , Melanoma, Experimental , Mice
18.
Article En | MEDLINE | ID: mdl-32335231

Lubricant oils are among oil-based products that are not fully consumed during its use, thereby producing non-biodegradable residues which can cause contamination of natural systems. This study evaluated the toxicity of new and used lubricating oil (0.01 and 0.1 mL L-1) in adult Nile tilapia (Oreochromis niloticus), by assessing the effects on oxidative stress, biotransformation enzymes (liver and gills), and histopathological alterations on hepatic and pancreatic tissues after 3 and 7 days of exposure. Results showed that 3-days exposure to 0.1 mL L-1 of used and new lubricating oil increased the activity of superoxide dismutase (SOD) and malondialdehyde (MDA) levels in liver of O. niloticus, respectively. In gills, catalase (CAT) was decreased in fish exposed to 0.1 mL L-1 of non-used oil after 3 days, but pronounced increases in CAT was detected after 7 days-exposure to both new and used oil. Shorter exposure to both concentrations of new and used oil also raised glutathione-S-transferase activity (GST) in gills. Ethoxyresorufin-O-deethylase (EROD) was induced in liver of fish exposed to 0.1 mL L-1of used oil after 3 and 7 days, however a reduced response of this enzyme was detected in gills of animals from both oil treatments. In vitro analysis showed that hepatic EROD was inhibited by lubricating oil exposures, with more pronounced responses in treatments containing used oil. Hepatic lesions, such as cytoplasmic vacuolization, nuclei abnormally, changes in hepatocytes shape, steatosis, cholestasis, eosinophilic inclusions and necrosis were mainly increased by 7 days exposure to used lubricating oil at higher concentration.


Cichlids/physiology , Gasoline/toxicity , Gene Expression Regulation, Enzymologic/drug effects , Liver/drug effects , Liver/pathology , Lubricants/toxicity , Oxidative Stress/drug effects , Animals , Automobiles , Biotransformation/drug effects , Catalase/genetics , Catalase/metabolism , Cichlids/genetics , Cichlids/metabolism , Cytochrome P-450 CYP1A1/genetics , Cytochrome P-450 CYP1A1/metabolism , Gills/drug effects , Gills/pathology , Glutathione Transferase/genetics , Glutathione Transferase/metabolism , Lipid Peroxidation/drug effects , Male , Superoxide Dismutase/genetics , Superoxide Dismutase/metabolism
19.
Sci Total Environ ; 723: 138030, 2020 Jun 25.
Article En | MEDLINE | ID: mdl-32213397

The early stages of the fish life cycle correspond to the phase that is most susceptible to deleterious effects caused by exposure to pollution. The aim of this study was to evaluate the quality of the anaerobic reactor effluent after three filtration-based treatments, namely, Double-Filtration in gravel and sand (DF), Triple-Filtration in gravel, sand and Activated Charcoal (TF-AC) and Triple-Filtration in gravel, sand and clinoptilolite (TF-C). The toxic effects on the population dynamics of larvae and embryos of catfish (Rhamdia quelen) to the final effluent were evaluated using an individual-based model (IBM). The results indicate that the three post-treatments produced effluents with significant improvement of the physicochemical parameters evaluated in relation to the anaerobic reactor effluent. In addition, all post-treatments improved the removal of metal ions. Experimental data showed high mortality rates for Rhamdia quelen embryos and larvae for most treatments, except for the effluent treated by TF-C. The results demonstrated that the concentration of ammoniacal nitrogen in relation to AR treatments (69.0); DF (44.0); TF-AC (46.6) and TF-C (0.33) in mg/L can be a limiting factor for the development of embryos and larvae during the ecotoxicity tests.


Filtration , Waste Disposal, Fluid , Anaerobiosis , Animals , Bioreactors , Charcoal , Nitrogen
20.
Toxicol In Vitro ; 61: 104640, 2019 Dec.
Article En | MEDLINE | ID: mdl-31493544

Neuroblastoma is an aggressive form of cancer with high mortality. Hydroxychalcones have received considerable attention because of their cytotoxic activities on cancer cells. However, the effect of the 4'-hydroxychalcone on neuroblastoma cells is unknown. The aim of the present study was to characterize the cytotoxicity of 4HC to neuroblastoma and the importance of mitochondrial effects in its action mechanism using an in vitro model of SH-SY5Y cells. Incubation of cultured SHSY5Y cells with 10-60 µM 4HC (24 h) decreased cell confluency, cellular metabolic activity and depleted intracellular ATP relative to the vehicle-treated control. The mechanism of 4HC-induced cell toxicity likely involves mitochondria dysfunctional as judged by inhibition of mitochondrial respiration, depolarization of mitochondria membrane potential and intracellular and morphological alterations. Furthermore, loss of cell viability was accompanied mainly by increase of phosphatidylserine exposure on the surface of cells, suggesting that the flavonoid may induce apoptosis in SH-SY5Y cells. In addition, treatment inhibited SH-SY5Y cell migration/proliferation in a scratch assay and induced significant changes in the cell cycle progression. Our results showed the effects of 4HC in the human neuroblastoma cell line SH-SY5Y are associated with mitochondrial dysfunctional, depletion of intracellular ATP levels, ROS increase, alteration in cell cycle progression and cellular morphology.


Antineoplastic Agents/pharmacology , Chalcones/pharmacology , Neuroblastoma/drug therapy , Adenosine Triphosphate/metabolism , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Humans , Membrane Potential, Mitochondrial/drug effects , Neuroblastoma/metabolism , Neuroblastoma/ultrastructure , Reactive Oxygen Species/metabolism
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