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1.
Chemosphere ; 365: 143294, 2024 Oct.
Article de Anglais | MEDLINE | ID: mdl-39265734

RÉSUMÉ

The influx of volcanic ash into seawater alters particle composition with implications for the cellular, physiological and anatomical response of suspension-feeding organisms. Adult females of Crepipatella peruviana were exposed to three diets consisting of a fixed concentration of 50,000 cells ml-1 of the microalga Isochrysis galbana plus different concentrations of ash particles (30, 90 and 150 mg L-1). The objective was to determine the cellular, physiological and anatomical responses. Mortality increased with ash concentrations, while feeding and respiration rates, tissue weight, and condition index decreased. The gills showed severe degradation of cilia and the presence of large mucous aggregates of cilia and ash. An increase in ash resulted in decreased lipid peroxidation and protein carbonyls, but increased total antioxidant capacity and phenols. Thus, volcanic ash particles may exert a high impact at both cellular and physiological levels for C. peruviana, where inhibition of gill function reduces the ability to acquire food.


Sujet(s)
Gastropoda , Branchies , Gastropoda/physiologie , Gastropoda/effets des médicaments et des substances chimiques , Animaux , Branchies/métabolisme , Branchies/effets des médicaments et des substances chimiques , Eau de mer/composition chimique , Femelle , Éruptions volcaniques , Peroxydation lipidique/effets des médicaments et des substances chimiques , Polluants chimiques de l'eau/analyse , Polluants chimiques de l'eau/toxicité , Antioxydants/métabolisme
2.
Article de Anglais | MEDLINE | ID: mdl-39218132

RÉSUMÉ

Polycyclic aromatic hydrocarbons (PAHs), such as phenanthrene (PHE), are common pollutants found in coastal areas where shrimp farming is developed. Even though PAHs can have adverse effects on physiology, shrimp can detoxify and metabolize toxic compounds and neutralize the reactive oxygen species (ROS) produced during this process. This requires the activation of multiple antioxidant enzymes, including peroxiredoxin 6 (Prx6). Prx6 uses glutathione (GSH) to reduce phospholipid hydroperoxides, a function shared with GSH peroxidase 4 (GPx4). Prx6 has been scarcely studied in crustaceans exposed to pollutants. Herein, we report a novel Prx6 from the shrimp Penaeus vannamei that is abundantly expressed in gills and hepatopancreas. To elucidate the involvement of Prx6 in response to PAHs, we analyzed its expression in the hepatopancreas of shrimp sub-lethally exposed to PHE (3.3 µg/L) and acetone (control) for 24, 48, 72, and 96 h, along with GPx4 expression, GSH-dependent peroxidase activity, and lipid peroxidation (indicated by TBARS). We found that GPx4 expression is not affected by PHE, but Prx6 expression and peroxidase activity decreased during the trial. This might contribute to the rise of TBARS found at 48 h of exposure. However, maintaining GPx4 expression could aid to minimize lipid damage during longer periods of exposure to PHE.


Sujet(s)
Glutathione peroxidase , Peroxydation lipidique , Penaeidae , Peroxiredoxin VI , Phénanthrènes , Phospholipid hydroperoxide glutathione peroxidase , Animaux , Phénanthrènes/toxicité , Peroxydation lipidique/effets des médicaments et des substances chimiques , Penaeidae/métabolisme , Penaeidae/effets des médicaments et des substances chimiques , Penaeidae/génétique , Penaeidae/enzymologie , Phospholipid hydroperoxide glutathione peroxidase/métabolisme , Phospholipid hydroperoxide glutathione peroxidase/génétique , Peroxiredoxin VI/métabolisme , Peroxiredoxin VI/génétique , Glutathione peroxidase/métabolisme , Glutathione peroxidase/génétique , Polluants chimiques de l'eau/toxicité , Hépatopancréas/métabolisme , Hépatopancréas/effets des médicaments et des substances chimiques , Branchies/métabolisme , Branchies/effets des médicaments et des substances chimiques , Protéines d'arthropode/métabolisme , Protéines d'arthropode/génétique
3.
Arch Environ Contam Toxicol ; 87(3): 253-269, 2024 Oct.
Article de Anglais | MEDLINE | ID: mdl-39322773

RÉSUMÉ

Although some biomarkers have already been determined in aeglids collected in the field, data from laboratory exposures are scarce. To our knowledge, no studies have investigated oxidative stress biomarkers in aeglids exposed to metals in the laboratory, or performed hemocyte counts and the comet assay using gill and hepatopancreas of aeglids. Thus, we investigated the effects of acute Cu exposure on intermolt males of Aegla castro, collected from a reference stream, acclimated for 6 days in the laboratory, and then exposed to 11 µg L-1 of dissolved Cu (Cu 11) or only to water (CTR), for 24 h. Gill and hepatopancreas samples were used to determine Cu accumulation, DNA damage, and metallothionein content (MT), while hemolymph samples were used to determine Cu accumulation, DNA damage, and hemocyte counts. Muscle samples were used to determine Cu accumulation and acetylcholinesterase activity (AChE). Non-protein thiol content (NPSH), catalase (CAT), glutathione S-transferase activities (GST), lipoperoxidation (LPO), and protein carbonylation content (PCC) were measured only in the hepatopancreas. Aegla castro exposed to Cu accumulated this metal in gills and activated detoxification mechanisms, through increased MT content in the gill, and showed an immune response, evidenced by an increase in hyaline hemocytes. Therefore, gill and hemocytes appear to have a protective role in preventing the transport and bioavailability of Cu through the body. On the other hand, we observed a decrease in MT content in the hepatopancreas of crabs exposed to Cu, suggesting the excretion of MT in association with Cu bound to the sulfhydryl groups of this protein.


Sujet(s)
Marqueurs biologiques , Cuivre , Altération de l'ADN , Branchies , Métallothionéine , Stress oxydatif , Polluants chimiques de l'eau , Animaux , Cuivre/toxicité , Polluants chimiques de l'eau/toxicité , Marqueurs biologiques/métabolisme , Stress oxydatif/effets des médicaments et des substances chimiques , Branchies/effets des médicaments et des substances chimiques , Branchies/métabolisme , Métallothionéine/métabolisme , Mâle , Amphipoda/effets des médicaments et des substances chimiques , Hépatopancréas/effets des médicaments et des substances chimiques , Hépatopancréas/métabolisme , Glutathione transferase/métabolisme , Hémocytes/effets des médicaments et des substances chimiques , Catalase/métabolisme , Test des comètes
4.
Sci Total Environ ; 953: 175984, 2024 Nov 25.
Article de Anglais | MEDLINE | ID: mdl-39244042

RÉSUMÉ

Alkyldimethylbenzylammonium chlorides (ADBACs), classified as second-generation quaternary ammonium compounds, are extensively employed across various sectors, encompassing veterinary medicine, food production, pharmaceuticals, cosmetics, ophthalmology, and agriculture. Consequently, significant volumes of ADBAC C12-C16 are discharged into the environment, posing a threat to aquatic organisms. Regrettably, comprehensive data regarding the toxicological characteristics of these compounds remain scarce. This research aimed to determine whether or not ADBAC C12-C16, at environmentally relevant concentrations (0.4, 0.8, and 1.6 µg/L), may instigate oxidative stress and alter the expression of apoptosis-related genes in the liver, brain, gut, and gills of Danio rerio adults (5-6 months). The findings revealed that ADBAC C12-C16 elicited an oxidative stress response across all examined organs following 96 h of exposure. Nonetheless, the magnitude of this response varied among organs, with the gills exhibiting the highest degree of susceptibility, followed by the gut, liver, and brain, in descending order. Only the gut and gills of the examined organs displayed a concentration-dependent reduction in the activity of superoxide dismutase (SOD) and catalase (CAT). Akin to the oxidative stress response, all organs exhibited a marked increase in bax, blc2, casp3, and p53 expression levels. However, the gills and gut manifested a distinctive suppression in the expression of nrf1 and nrf2. Our Principal Component Analysis (PCA) confirmed that SOD, CAT, nrf1, and nrf2 were negatively correlated to oxidative damage biomarkers and apoptosis-related genes in the gills and gut; meanwhile, in the remaining organs, all biomarkers were extensively correlated. From the above, it can be concluded that ADBAC C12-C16 in low and environmental concentrations may threaten the health of freshwater fish.


Sujet(s)
Stress oxydatif , Polluants chimiques de l'eau , Danio zébré , Animaux , Polluants chimiques de l'eau/toxicité , Stress oxydatif/effets des médicaments et des substances chimiques , Branchies/effets des médicaments et des substances chimiques , Branchies/métabolisme , Composés de benzalkonium/toxicité
5.
Environ Toxicol ; 39(11): 5048-5058, 2024 Nov.
Article de Anglais | MEDLINE | ID: mdl-39051743

RÉSUMÉ

Microplastics (MPs) and glyphosate-based herbicides (GBH) are among the most common contaminants in aquatic environments. In Brazilian rivers, both contaminants were found in elevated levels, leading to a high probability of their association, which can alter their individual effects and potentially intensify their toxicity. This study evaluated the isolated and combined effects of polyethylene microplastics (PE-MPs) and GBH on Oreochromis niloticus using multi-biomarkers of toxicity. The fish were subjected to a 96-h exposure period, with concentrations set based either isolated, PE-MPs group (5 mg L-1), GBH group (5 mg L-1), or in a group of associated contaminants (GAC), PE-MP + GBH (5 mg L-1 + 5 mg L-1). Toxicity effects were evaluated using biochemical, cytogenetic, hematological, and histopathological biomarkers. We observed change in erythrocyte parameters leading to macrocytic normochromic anemia in GAC. Leukocyte parameters indicate a nonspecific immunosuppression caused by the exposure of associated contaminants, besides the attempts to repair damage caused by PE-MPs. Histopathological markers indicate damage to tissues exposed to contaminants. Besides, there were morphophysiological adjustments on gills, with proliferation and hypertrophy of mitochondria-rich cells on GBH and GAC, besides epithelium ruptures, which were mostly present in the exposed groups. Therefore, this study indicates that PE-MPs and GBHs present toxic effects in O. niloticus with the used concentrations, intensified by the association of contaminants. Thus, multi-biomarkers were useful key to verify toxicity, providing data to the investigation of high levels of contaminant's mixture toxicity present in aquatic environments.


Sujet(s)
Marqueurs biologiques , Cichlides , Branchies , Glycine , Glyphosate , Herbicides , Microplastiques , Polyéthylène , Polluants chimiques de l'eau , Animaux , Branchies/effets des médicaments et des substances chimiques , Branchies/anatomopathologie , Polluants chimiques de l'eau/toxicité , Microplastiques/toxicité , Glycine/analogues et dérivés , Glycine/toxicité , Marqueurs biologiques/métabolisme , Polyéthylène/toxicité , Herbicides/toxicité , Brésil
6.
Environ Sci Pollut Res Int ; 31(32): 45425-45440, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38965109

RÉSUMÉ

Ivermectin (IVM) is a widely used antiparasitic. Concerns have been raised about its environmental effects in the wetlands of Río de la Plata basin where cattle have been treated with IVM for years. This study investigated the sublethal effects of environmentally relevant IVM concentrations in sediments on the Neotropical fish Prochilodus lineatus. Juvenile P. lineatus were exposed to IVM-spiked sediments (2 and 20 µg/Kg) for 14 days, alongside a control sediment treatment without IVM. Biochemical and oxidative stress responses were assessed in brain, gills, and liver tissues, including lipid damage, glutathione levels, enzyme activities, and antioxidant competence. Muscle and brain acetylcholinesterase activity (AChE) and stable isotopes of 13C and 15N in muscle were also measured. The lowest IVM treatment resulted in an increase in brain lipid peroxidation, as measured by thiobarbituric acid reactive substances (TBARs), decreased levels of reduced glutathione (GSH) in gills and liver, increased catalase activity (CAT) in the liver, and decreased antioxidant capacity against peroxyl radicals (ACAP) in gills and liver. The highest IVM treatment significantly reduced GSH in the liver. Muscle (AChE) was decreased in both treatments. Multivariate analysis showed significant overall effects in the liver tissue, followed by gills and brain. These findings demonstrate the sublethal effects of IVM in P. lineatus, emphasizing the importance of considering sediment contamination and trophic habits in realistic exposure scenarios.


Sujet(s)
Antiparasitaires , Ivermectine , Polluants chimiques de l'eau , Animaux , Ivermectine/toxicité , Antiparasitaires/toxicité , Polluants chimiques de l'eau/toxicité , Bétail , Amérique du Sud , Stress oxydatif/effets des médicaments et des substances chimiques , Sédiments géologiques/composition chimique , Branchies/effets des médicaments et des substances chimiques , Branchies/métabolisme
7.
Mar Pollut Bull ; 206: 116696, 2024 Sep.
Article de Anglais | MEDLINE | ID: mdl-39042981

RÉSUMÉ

The activities of catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), glucose-6-phosphate dehydrogenase (G6PDH), and glutathione-S-transferase (GST) were evaluated in the gills (GI) and digestive gland (DG) of Magallana gigas oysters exposed to tamoxifen (TAM) at environmental concentrations of 10 and 100 ng L-1 for 1 and 4 days. A higher CAT activity in the GI and DG and higher GPx activity only in the DG was observed of oysters exposed to both concentrations after 1 day. Furthermore, a significant increase in GR and G6PDH, was detected in the DG after 1 day of exposure to 10 ng L-1 and only G6PDH activity increase after 1 day of exposure to 10 ng L-1 in the GI. This suggests that the DG is a tissue more sensitive to TAM exposure and was confirmed with the individual Integrated Biomarker Response version 2 index (IBRv2i), highlighting the acute stress caused by TAM and a cellular adaptation.


Sujet(s)
Catalase , Glutathione peroxidase , Glutathione reductase , Glutathione transferase , Ostreidae , Tamoxifène , Polluants chimiques de l'eau , Animaux , Polluants chimiques de l'eau/toxicité , Tamoxifène/toxicité , Ostreidae/métabolisme , Ostreidae/effets des médicaments et des substances chimiques , Catalase/métabolisme , Glutathione peroxidase/métabolisme , Glutathione reductase/métabolisme , Glutathione transferase/métabolisme , Branchies/effets des médicaments et des substances chimiques , Branchies/métabolisme , Glucose 6-phosphate dehydrogenase/métabolisme , Marqueurs biologiques/métabolisme
8.
Ecotoxicology ; 33(6): 630-641, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-38777922

RÉSUMÉ

In Brazil, glyphosate is present in more than 130 commercial formulations, and its toxic effects have already been tested in different species to understand its impact on biota Decapod crustaceans are widely used as experimental models due to their biology, sensitivity to pollutants, ease of collection, and maintenance under laboratory conditions. We evaluated the changes in metabolism (hemolymph) and oxidative balance markers (gill and hepatopancreas) of a crayfish (Parastacus promatensis) after exposure to Roundup® (active ingredient: glyphosate). The crayfish were captured in the Garapiá stream within the Center for Research and Conservation of Nature Pró-Mata, Brazil. We collected adult animals outside (fall) and during (spring) the breeding season. The animals were transported in buckets with cooled and aerated water from the collection site to the aquatic animal maintenance room at the university. After acclimatization, the animals were exposed to different concentrations of glyphosate (0, 65, 260, 520, and 780 µg/L). The results showed a significant variation in the hemolymph glucose, lactate, and protein levels. We observed variations in the tissue antioxidant enzymatic activity after exposure to glyphosate. Finally, the increase in oxidative damage required a high energy demand from the animals to maintain their fitness, which makes them more vulnerable to stress factors added to the habitat.


Sujet(s)
Branchies , Glycine , Glyphosate , Hémolymphe , Hépatopancréas , Stress oxydatif , Polluants chimiques de l'eau , Animaux , Hémolymphe/métabolisme , Hémolymphe/effets des médicaments et des substances chimiques , Hépatopancréas/effets des médicaments et des substances chimiques , Hépatopancréas/métabolisme , Polluants chimiques de l'eau/toxicité , Glycine/analogues et dérivés , Glycine/toxicité , Stress oxydatif/effets des médicaments et des substances chimiques , Branchies/métabolisme , Branchies/effets des médicaments et des substances chimiques , Herbicides/toxicité , Astacoidea/effets des médicaments et des substances chimiques , Astacoidea/physiologie , Brésil
9.
Environ Pollut ; 349: 123904, 2024 May 15.
Article de Anglais | MEDLINE | ID: mdl-38565392

RÉSUMÉ

The indiscriminate and, very often, incorrect use of pesticides in Brazil, as well as in other countries, results in severe levels of environmental pollution and intoxication of human life. Herein, we studied plasma membrane models (monolayer and bilayer) of the phospholipid Dioleoyl-sn-glycerol-3-phosphocholine (DOPC) using Langmuir films, and large (LUVs) and giant (GUVs) unilamellar vesicles, to determine the effect of the pesticides chlorantraniliprole (CLTP), isoxaflutole (ISF), and simazine (SMZ), used in sugarcane. CLTP affects the lipid organization of the bioinspired models of DOPC π-A isotherms, while ISF and SMZ pesticides significantly affect the LUVs and GUVs. Furthermore, the in vivo study of the gill tissue in fish in the presence of pesticides (2.0 × 10-10 mol/L for CLTP, 8.3 × 10-9 mol/L for ISF, and SMZ at 9.9 × 10-9 mol/L) was performed using optical and fluorescence images. This investigation was motivated by the gill lipid membranes, which are vital for regulating transporter activity through transmembrane proteins, crucial for maintaining ionic balance in fish gills. In this way, the presence of phospholipids in gills offers a model for understanding their effects on fish health. Histological results show that exposure to CLTP, ISF, and SMZ may interfere with vital gill functions, leading to respiratory disorders and osmoregulation dysfunction. The results indicate that exposure to pesticides caused severe morphological alterations in fish, which could be correlated with their impact on the bioinspired membrane models. Moreover, the effect does not depend on the exposure period (24h and 96h), showing that animals exposed to pesticides for a short period suffer irreparable damage to gill tissue. In summary, we can conclude that the harm caused by pesticides, both in membrane models and in fish gills, occurs due to contamination of the aquatic system with pesticides. Therefore, water quality is vital for the preservation of ecosystems.


Sujet(s)
Branchies , Pesticides , Phospholipides , Tilapia , ortho-Aminobenzoates , Animaux , Branchies/effets des médicaments et des substances chimiques , Branchies/métabolisme , Phospholipides/métabolisme , Pesticides/toxicité , Tilapia/métabolisme , ortho-Aminobenzoates/toxicité , Polluants chimiques de l'eau/toxicité , Membrane cellulaire/effets des médicaments et des substances chimiques , Brésil
10.
Environ Sci Pollut Res Int ; 31(20): 29794-29810, 2024 Apr.
Article de Anglais | MEDLINE | ID: mdl-38592632

RÉSUMÉ

Microplastics, considered emerging environmental contaminants resulting from plastic degradation, are discovered in diverse aquatic ecosystems and can be unintentionally ingested by fish. Therefore, it is essential to characterize their interaction with other contaminants, such as agrochemicals, in aquatic environments. This study aimed to assess histological, enzymatic, and genotoxic biomarkers in juvenile pacú (Piaractus mesopotamicus) exposed to polyethylene (PE) microplastic particles and the herbicide atrazine, individually or combined, for 15 days. Four treatments were used: a negative control (CON), PE in the fish diet (0.1% w/w, FPE), atrazine through water (100 µg L-1, ATZ), and the mixture (ATZ+FPE). Results confirmed histological alterations in gills (edema and lamellar fusion) and liver (necrotic areas and congestion) of fish exposed to ATZ and ATZ+FPE. The number of goblet cells increased in the posterior intestine of fish under ATZ+FPE compared to CON and FPE. Enzyme activities (CAT, GST, AChE, and BChE) significantly increased in ATZ+FPE compared to CON. However, no genotoxic effect was demonstrated. These findings provide insights into the complex impacts of simultaneous exposure to atrazine and microplastics, emphasizing the need for continued research to guide effective environmental management strategies against these contaminants that represent a risk to aquatic organisms.


Sujet(s)
Atrazine , Microplastiques , Polluants chimiques de l'eau , Atrazine/toxicité , Microplastiques/toxicité , Animaux , Polluants chimiques de l'eau/toxicité , Branchies/effets des médicaments et des substances chimiques
11.
J Toxicol Environ Health A ; 85(7): 291-306, 2022 04 03.
Article de Anglais | MEDLINE | ID: mdl-34879786

RÉSUMÉ

Triclosan (TCS) is a synthetic broad-spectrum antimicrobial agent commonly used world-wide in a range of personal care and sanitizing products detected frequently in aquatic ecosystems. The aim of this study was to examine biochemical markers responses triggered by TCS in Danio rerio and in a native South American fish species (Corydoras paleatus). Further, an integrated approach comparing both test fish species was undertaken. These fish organisms were exposed to 100 or 189 µg TCS/L for 48 h. The activities of catalase (CAT), glutathione-s-transferase (GST), superoxide dismutase (SOD), and lipid peroxidation levels (LPO) and total antioxidant capacity against peroxyl radicals (ACAP) were determined in liver, gills, and brain. Acetylcholinesterase activity (AChE) was measured in the brain. Multivariate analysis showed that the most sensitive hepatic parameters were activities of GST and SOD for C. paleatus while LPO levels were for D. rerio. In gills the same parameters were responsive for C. paleatus but CAT in D. rerio. ACAP and GST activity were responsive parameters in brain of both species. Integrated biomarker responses (IBR) index demonstrated similar trends in both species suggesting this parameter might serve as a useful tool for quantification of integrated responses induced by TCS.


Sujet(s)
Anti-infectieux locaux/toxicité , Marqueurs biologiques , Stress oxydatif/effets des médicaments et des substances chimiques , Triclosan/toxicité , Polluants chimiques de l'eau/toxicité , Animaux , Encéphale/effets des médicaments et des substances chimiques , Encéphale/enzymologie , Poissons-chats , Branchies/effets des médicaments et des substances chimiques , Branchies/enzymologie , Foie/effets des médicaments et des substances chimiques , Foie/enzymologie , Danio zébré
12.
Article de Anglais | MEDLINE | ID: mdl-34411697

RÉSUMÉ

Tropical gar (Atractosteus tropicus) thrives in aquatic habitats with high levels of total nitrogen (TAN) and unionized ammonia (NH3). However, the tolerance of TAN and NH3, the excretion mechanisms involved, and the effects of these chemicals on routine metabolism are still unknown. Therefore, our objectives were to assess the acute toxicity of TAN and NH3 in A. tropicus juveniles after a 96-h exposure (LC50-96 h) to NH4Cl and after chronic exposure to two concentrations (15% and 30% of LC50-96 h TAN) for 12 days, as well as to evaluate the transcriptional effects associated with Rhesus proteins (rhag, rhbg, rhcg) and ion transporters (NHE, NKA, NKCC, and CFTR) in gills and skin; and to determine the effects of TAN and NH3 on routine metabolism through oxygen consumption (µM g-1 h-1) and gill ventilation frequency (beats min-1). LC50-96 h values were 100.20 ± 11.21 mg/L for TAN and 3.756 ± 0.259 mg/L for NH3. The genes encoding Rhesus proteins and ion transporters in gills and skin showed a differential expression according to TAN concentrations and exposure time. Oxygen consumption on day 12 showed significant differences between treatments with 15% and 30% TAN. Gill ventilation frequency on day 12 was higher in fish exposed to 30% TAN. In conclusion, A. tropicus juveniles are highly tolerant to TAN, showing upregulation of the genes involved in TAN excretion through gills and skin, which affects routine oxygen consumption and energetic cost. These findings are relevant for understanding adaptations in the physiological response of a tropical ancestral air-breathing fish.


Sujet(s)
Ammoniac/toxicité , Protéines de transport/métabolisme , Protéines de poisson/métabolisme , Poissons/métabolisme , Azote/toxicité , Animaux , Protéines de transport/génétique , Protéines de poisson/génétique , Poissons/croissance et développement , Branchies/effets des médicaments et des substances chimiques , Branchies/métabolisme , Branchies/anatomopathologie , Transport des ions , Larve , Peau/effets des médicaments et des substances chimiques , Peau/métabolisme , Peau/anatomopathologie , Polluants chimiques de l'eau/toxicité
13.
Article de Anglais | MEDLINE | ID: mdl-34418533

RÉSUMÉ

DCOIT is a co-biocide that is part of the formulation of the commercial antifouling Sea-Nine 211® and although it is "safe to use", negative effects have been reported on the antioxidant defense system of non-target organisms. Therefore, the objective of this research was to verify and compare the response of antioxidant enzymes of juveniles and adults of Amarilladesma mactroides exposed to DCOIT. The animals were exposed to solvent control (DMSO 0.01%) and DCOIT (measured concentration 0.01 mg/L and 0.13 mg/L) for 96 h, then gills, digestive gland and mantle were collected for analysis of the enzymatic activity of glutathione S-transferase (GST), superoxide dismutase (SOD) and catalase (CAT). The results revealed that adults, in relation to juveniles, have low basal activity of GST and SOD enzymes in the gills and digestive gland and high basal activity of SOD and CAT in the mantle. DCOIT did not alter GST activity in the gills of any life stage, while both concentrations decreased SOD and CAT in adults. In the digestive gland, it was observed that DCOIT (0.13 mg/L) decreased the GST activity in adults and CAT in juveniles, and both concentrations of the co-biocide decreased the SOD and CAT in adults. In the mantle, DCOIT (0.13 mg/L) increased CAT in juveniles. We conclude that juveniles have greater basal activity of antioxidant enzymes than adults and, in addition, DCOIT negatively affected the adults of A. mactroides, mainly decreasing the activity of GST, SOD and CAT in the gills and digestive gland of these organisms.


Sujet(s)
Antioxydants/métabolisme , Bivalvia/effets des médicaments et des substances chimiques , Thiazoles/toxicité , Animaux , Bivalvia/croissance et développement , Bivalvia/métabolisme , Branchies/effets des médicaments et des substances chimiques , Branchies/métabolisme , Branchies/anatomopathologie , Peroxydation lipidique/effets des médicaments et des substances chimiques , Stress oxydatif/effets des médicaments et des substances chimiques , Polluants chimiques de l'eau/toxicité
14.
Article de Anglais | MEDLINE | ID: mdl-34126254

RÉSUMÉ

Aeglids are unique freshwater decapods whose habitats are being impacted by metallic compounds, such as copper (Cu). Thus, we investigated the effects of acute Cu exposure on ionic regulation of Aegla castro. For this, male specimens in intermolt were collected from a reference stream and acclimated for 5 days in laboratory. After which, crabs were exposed to 11 µg L-1 Cu (Cu11) or only to water (CTR) for 24 h. Hemolymph samples were withdrawn for the determination of Na+, K+, Ca2+, and Mg2+ concentrations and the posterior gills removed for the analysis of Na+/K+-ATPase, Ca2+-ATPase, H+-ATPase, and carbonic anhydrase (CA) activities. Increased Ca2+ and Mg2+ hemolymph concentrations were observed in animals from Cu11, when compared with CTR group. In addition, decreased activity of CA was observed in animals exposed to Cu. In the current study, alterations in Ca2+ and Mg2+concentrations probably indicate that animals activated exoskeleton reabsorption mechanisms, characteristic of the premolt. Therefore, increased Ca2+ and Mg2+ concentrations in hemolymph may indicate that a biochemical signal associated with the molting cycle was triggered by Cu exposure. Despite the known harmful effects of Cu on osmoregulatory enzymes, here we observed decreased activity only in CA. However, decreased activity of CA could trigger both acid-base imbalance and ionic disruption, since CA provides H+ and HCO3- for intracellular pH maintenance, and underpins Na+ and Cl- for ionic regulation. Therefore, understanding how aeglids respond to metal contamination in laboratory conditions is crucial to assess their potential as an alternative biological model for aquatic ecotoxicology.


Sujet(s)
Brachyura/effets des médicaments et des substances chimiques , Cuivre/toxicité , Polluants chimiques de l'eau/toxicité , Animaux , Marqueurs biologiques , Brachyura/physiologie , Inhibiteurs de l'anhydrase carbonique/toxicité , Carbonic anhydrases/métabolisme , Branchies/effets des médicaments et des substances chimiques , Branchies/enzymologie , Mâle , Équilibre hydroélectrolytique/effets des médicaments et des substances chimiques
15.
Environ Toxicol Pharmacol ; 85: 103634, 2021 Jul.
Article de Anglais | MEDLINE | ID: mdl-33741518

RÉSUMÉ

Female juveniles of the Neotropical fish Astyanax altiparanae were exposed for 96 h to four treatments containing the active ingredient from Imidacloprid® commercial formulation (IMI 1, IMI 2, IMI 3, and IMI 4) and to a control treatment (only dechlorinated tap water). Glutathione content, glutathione S-transferase activity, lipid peroxidation (LPO) and protein carbonylation levels, acetylcholinesterase (AChE) activity, and frequency of micronuclei and erythrocyte nuclear abnormalities (ENA) were measured in the fish. The muscle and gills were the most affected organs; their antioxidant defense was not enough to prevent oxidative damage (LPO) in the IMI 2 and IMI 4 treatment fish. IMI also inhibited AChE activity in the muscle (IMI 3 and IMI 4) and increased ENA frequency (IMI 4). IMI can affect the health of A. altiparanae in environmentally relevant concentrations, causing oxidative damage in different organs, neurotoxic effects in the muscle, and genotoxicity.


Sujet(s)
Characidae , Insecticides/toxicité , Néonicotinoïdes/toxicité , Composés nitrés/toxicité , Polluants chimiques de l'eau/toxicité , Acetylcholinesterase/métabolisme , Animaux , Encéphale/effets des médicaments et des substances chimiques , Encéphale/métabolisme , Femelle , Protéines de poisson/métabolisme , Eau douce , Branchies/effets des médicaments et des substances chimiques , Branchies/métabolisme , Glutathion/métabolisme , Foie/effets des médicaments et des substances chimiques , Foie/métabolisme , Tests de micronucleus , Muscles/effets des médicaments et des substances chimiques , Muscles/métabolisme , Syndromes neurotoxiques/métabolisme , Stress oxydatif/effets des médicaments et des substances chimiques , Carbonylation des protéines/effets des médicaments et des substances chimiques
16.
Article de Anglais | MEDLINE | ID: mdl-33548546

RÉSUMÉ

The multixenobiotic resistance mechanism (MXR) can decrease intracellular genotoxic pressure through the efflux of compounds out of the cell. Thus, this work presents a temporal approach to evaluate the MXR activity and the occurrence of genotoxic damage in different organs of the fish Prochilodus lineatus after an intraperitoneal injection of benzo[a]pyrene (B[a]P). Although the liver and brain demonstrated rapid MXR induction (6 h), the occurrence of DNA damage was not prevented. However, these organs presented some return to DNA integrity after MXR activity. The kidney demonstrated the slowest response in the MXR induction (24 h), which may be related to the preferential excretion of B[a]P metabolites by this route. Moreover, the kidney MXR reduction at 96 h may be related to its role in the excretion of metabolites from all other metabolizing organs. The gills did not appear to play an essential role in xenobiotics efflux; however, their participation in biotransformation is exhibited through the occurrence of DNA damage. The integrated response of the organs in the dynamics for the maintenance of the organism integrity could be promoted by the circulation of the xenobiotic through the bloodstream, which corroborates the increase in the DNA damage in the erythrocytes at 6 h. Therefore, the ability to induce MXR was linked to the preservation of DNA integrity in the presence of B[a]P, since MXR acts to avoid the accumulation of xenobiotics inside the cell.


Sujet(s)
Benzo[a]pyrène , Characiformes/métabolisme , Polluants chimiques de l'eau , Xénobiotique , Animaux , Benzo[a]pyrène/pharmacocinétique , Benzo[a]pyrène/toxicité , Biotransformation , Encéphale/effets des médicaments et des substances chimiques , ADN/métabolisme , Altération de l'ADN , Branchies/effets des médicaments et des substances chimiques , Foie/effets des médicaments et des substances chimiques , Polluants chimiques de l'eau/pharmacocinétique , Polluants chimiques de l'eau/toxicité , Xénobiotique/pharmacocinétique , Xénobiotique/toxicité
17.
Environ Toxicol Pharmacol ; 83: 103596, 2021 Apr.
Article de Anglais | MEDLINE | ID: mdl-33482285

RÉSUMÉ

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.


Sujet(s)
Cichlides , Polluants chimiques de l'eau/toxicité , Acetylcholinesterase/métabolisme , Animaux , Encéphale/effets des médicaments et des substances chimiques , Encéphale/métabolisme , Brésil , Catalase/métabolisme , Cichlides/sang , Cichlides/métabolisme , Femelle , Branchies/effets des médicaments et des substances chimiques , Branchies/anatomopathologie , Glutathione transferase/métabolisme , Gonades/effets des médicaments et des substances chimiques , Gonades/anatomopathologie , Hydrocarbures chlorés/analyse , Hydrocarbures chlorés/toxicité , Foie/effets des médicaments et des substances chimiques , Foie/métabolisme , Foie/anatomopathologie , Mâle , Métaux lourds/analyse , Métaux lourds/toxicité , Muscles/effets des médicaments et des substances chimiques , Muscles/métabolisme , Hydrocarbures aromatiques polycycliques/analyse , Hydrocarbures aromatiques polycycliques/toxicité , Carbonylation des protéines/effets des médicaments et des substances chimiques , Rivières , Vitellogénines/sang , Polluants chimiques de l'eau/analyse
18.
Ecotoxicol Environ Saf ; 208: 111589, 2021 Jan 15.
Article de Anglais | MEDLINE | ID: mdl-33396112

RÉSUMÉ

Marine bivalves have been widely applied as environmental contamination bioindicators, although studies concerning tropical species are less available compared to temperate climate species. Assessments regarding Perna perna mytilid mussels, in particular, are scarce, even though this is an extremely important species in economic terms in tropical countries, such as Brazil. To this end, Perna perna mytilids were sampled from two tropical bays in Southeastern Brazil, one anthropogenically impacted and one previously considered a reference site for metal contamination. Gill metallothionein (MT), reduced glutathione (GSH), carboxylesterase (CarbE) and lipid peroxidation (LPO) were determined by UV-vis spectrophotometry, and metal and metalloid contents were determined by inductively coupled plasma mass spectrometry (ICP-MS). Metalloprotein metal detoxification routes in heat-stable cellular gill fractions were assessed by size exclusion high performance chromatography (SEC-HPLC) coupled to an ICP-MS. Several associations between metals and oxidative stress endpoints were observed at all four sampling sites through a Principal Component Analysis. As, Cd, Ni and Se contents, in particular, seem to directly affect CarbE activity. MT is implicated in playing a dual role in both metal detoxification and radical oxygen species scavenging. Differential SEC-HPLC-ICP-MS metal-binding profiles, and, thus, detoxification mechanisms, were observed, with probable As-, Cu- and Ni-GSH complexation and binding to low molecular weight proteins. Perna perna mussels were proven adequate tropical bioindicators, and further monitoring efforts are recommended, due to lack of data regarding biochemical metal effects in tropical species. Integrated assessments, as performed herein demonstrate, are invaluable in evaluating contaminated aquatic environments, resulting in more accurate ecological risk assessments.


Sujet(s)
Métaux/toxicité , Perna/physiologie , Polluants chimiques de l'eau/toxicité , Animaux , Baies (géographie) , Brésil , Surveillance de l'environnement , Branchies/effets des médicaments et des substances chimiques , Glutathion/métabolisme , Métalloprotéines/métabolisme , Métallothionéine/métabolisme , Métaux/analyse , Métaux/métabolisme , Perna/effets des médicaments et des substances chimiques , Produits de la mer/analyse , Polluants chimiques de l'eau/analyse , Polluants chimiques de l'eau/métabolisme
19.
Ecotoxicol Environ Saf ; 208: 111601, 2021 Jan 15.
Article de Anglais | MEDLINE | ID: mdl-33396121

RÉSUMÉ

Atrazine (ATZ) is among the most widely used herbicides in the world, and yet it has a potential to contaminate aquatic environments due to pesticide leaching from agricultural areas. In the Neotropical region, studies about the effects of this herbicide in native aquatic wildlife is scarce.Our study aimed at investigating the effects of a 30-day exposure to a commercial atrazine formulation on oxidative stress parameters, histopathology in testis and liver, and hormone levels in males and female of yellow-tailed tetra fish (Astyanax altiparanae). Adults were exposed to low but environmentally relevant concentrations of atrazine as follows: 0 (CTL-control), 0.5 (ATZ0.5), 1 (ATZ1), 2 (ATZ2) and 10 (ATZ10) µg/L. Our results showed decreased GST activity in gills in all groups of exposed animals and increased CAT activity in gills from the ATZ10 group. In the liver, there was an increase in lipid peroxidation in fish from ATZ1 and ATZ2 groups. Histological analysis of the liver showed increased percentage of sinusoid capillaries in ATZ2 fish, increased vascular congestion in ATZ1 and increased leukocyte infiltration in the ATZ10 group. Hepatocyte diameter analysis revealed a decrease in cell size in all groups exposed to ATZ, and a decrease in hepatocyte nucleus diameter in ATZ1, ATZ2 and ATZ10 groups. Endocrine parameters did not show significant changes following ATZ exposure, although an increase of triiodothyronine/thyroxine (T3/T4) ratio was observed in ATZ2 fish. Our results provide evidence that even low, environmentally relevant concentrations of ATZ produced oxidative damage and histological alterations in adult yellow-tailed tetra.


Sujet(s)
Atrazine/toxicité , Characidae/métabolisme , Herbicides/toxicité , Stress oxydatif/effets des médicaments et des substances chimiques , Polluants chimiques de l'eau/toxicité , Animaux , Atrazine/métabolisme , Relation dose-effet des médicaments , Femelle , Branchies/effets des médicaments et des substances chimiques , Branchies/métabolisme , Herbicides/métabolisme , Peroxydation lipidique/effets des médicaments et des substances chimiques , Foie/effets des médicaments et des substances chimiques , Foie/métabolisme , Foie/anatomopathologie , Mâle , Testicule/effets des médicaments et des substances chimiques , Testicule/métabolisme , Testicule/anatomopathologie , Polluants chimiques de l'eau/métabolisme
20.
Ecotoxicol Environ Saf ; 208: 111603, 2021 Jan 15.
Article de Anglais | MEDLINE | ID: mdl-33396123

RÉSUMÉ

Chlorothalonil (CLT) is a broad spectrum, and non-systemic fungicide applied in foliar structures to prevent and treat pathogens. This compound reaches to aquatic environments and affects the biota. In this context, the main goal of this study was to assess the effects of CLT at biochemical, tissular, and individual levels of biological organization using the invasive bivalve Corbicula largillierti as a bioindicator species. Clams were exposed to different sublethal concentrations (0, 10, 20 and 50 µg. L-1 CLT) for 96 h. At biochemical level, the enzymatic activity (Glutathione-s-Transferase, Catalase, Acetyl-, Butiryl- and Carboxyl-esterases) and lipid peroxidation were measured in gills and the visceral mass. Also, the digestive gland morphometry through quantitative histological indexes was registered at the tissular level. Finally, filtering activity and burial behavior at the individual level were measured. At the highest CLT concentration, the most significant changes were observed in enzymatic activity (except for butyrylcholinesterase), lipid peroxidation and in digestive gland morphometry. It was also registered increases of the filtering activity and the latency time to burial. Most of the biomarkers assessed showed significant responses under CLT exposure. Therefore, taking into account that C. largillierti was affected by CLT, it can be expected that other species could be in a potential risk if this fungicide is present in freshwater systems.


Sujet(s)
Corbicula/effets des médicaments et des substances chimiques , Surveillance de l'environnement/méthodes , Eau douce/composition chimique , Fongicides industriels/toxicité , Nitriles/toxicité , Polluants chimiques de l'eau/toxicité , Animaux , Marqueurs biologiques/métabolisme , Catalase/métabolisme , Corbicula/enzymologie , Relation dose-effet des médicaments , Fongicides industriels/analyse , Branchies/effets des médicaments et des substances chimiques , Branchies/enzymologie , Glutathione transferase/métabolisme , Peroxydation lipidique/effets des médicaments et des substances chimiques , Nitriles/analyse , Polluants chimiques de l'eau/analyse
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