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1.
Aquat Toxicol ; 233: 105789, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33667915

RESUMO

Fluoride has been found to cause detrimental effects on fish gills. Despite essential roles in various metabolism activities, whether and how miRNAs participate in the course of toxicity caused by fluoride in gills is still unclear. In this study, male zebrafish were exposed to 0, 20, 40 mg/L fluoride for 60 days to study the underlying osmotic regulatory mechanism by determining the influences of fluoride on the miRNAs and regulated genes in gills. mRNAs were isolated from the gills and the expression profiles were analyzed by using Illumina Hiseq 2500 platforms. Expressions of 7 differentially miRNAs and some related-genes in gills were validated by qRT-PCR. The results showed that miRNAs expressions were notably altered by fluoride. A total of 584 and 327 miRNAs were remarkably changed after 20 and 40 mg/L fluoride exposure, of which 322 were increased and 262 were decreased in 20 mg/L fluoride group, whereas 219 were elevated and 108 were reduced in 40 mg/L fluoride group. The differentially expressive miRNAs confirmed by qRT-PCR were consistent with micro-assay data. Cluster of Orthologous Groups of proteins (COG) function classification showed that the target genes of differentially expressive miRNAs are mainly related to signal transduction mechanisms, replication, transcription, inorganic ion transport and metabolism, repair and recombination, and energy formation and transformation. In addition, fluoride disturbed the expressions of target genes involved in the osmoregulation of the gill in the fluoride-exposed zebrafish, such as the increased expressions of OSTF1 and the decreased expressions of Na+-K+-ATPase, CFTR, and AQP-3, which provides a possibility that miRNAs regulation induced by fluoride has an effects on osmotic regulation, providing new hints to the osmotic regulatory mechanism of the toxicity caused by fluoride in zebrafish, and distinguishes new biomarkers of miRNAs for fluoride toxicity.


Assuntos
Fluoretos/toxicidade , Expressão Gênica/efeitos dos fármacos , Brânquias/efeitos dos fármacos , MicroRNAs/metabolismo , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/metabolismo , Animais , Brânquias/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Masculino , MicroRNAs/genética , Peixe-Zebra/genética
2.
Aquat Toxicol ; 233: 105775, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33631492

RESUMO

Cadmium (Cd)-caused water environment pollution has become a matter of concern. Gill is an organ with respiratory and mucosal immune functions, and is also one of the organs directly attacked by pollutants. It was found that excess Cd could cause Cd accumulation and gill injury in carp. However, the mechanism of Cd-caused damage in common carp gills is still unclear. Oxidative stress, immunosuppression, and apoptosis took part in the mechanism of poisoning caused by some harmful substances. The aim of the study was to investigate complex molecular mechanism of apoptotic injury caused by Cd in common carp gills. Hence, in this study, we established a Cd poisoning model to explore whether excess Cd can induce apoptosis through observing histomorphology and apoptotic cells; and determining mineral elements, oxidative stress-related factors, immune-related, and apoptosis-related genes in common carp gills. Fifty-four fish were randomly separated into the control group and the Cd group and were cultured for 45 days. The water of the control group was drinking water and the water of the Cd group was CdCl2-added drinking water (0.26 mg/L Cd). In our results, we found that excess Cd increased Cd level, decreased the levels of essential mineral elements (Cu, Fe, Zn, and Mn), damaged mitochondria, and increased apoptotic cells in common carp gills, meaning that excess Cd caused Cd accumulation and apoptotic injury via mitochondrion in common carp gills. Furthermore, we found that Cd inhibited anti-apoptosis-related gene Bcl-2 and stimulated pro-apoptosis-related genes (JNK, FoxO3a, PUMA, Bax, Apaf-1, Caspase-9, and Caspase-3) on 15th, 30th, and 45th days. Above data meant that Cd exposure caused apoptosis via mitochondrion and JNK-FoxO3a-PUMA pathway in common carp gills. In addition, in our experiment, Cd treatment increased oxidants (H2O2 and MDA) and decreased antioxidants (CAT, GPx, GST, SOD, T-AOC, and GSH), indicating that Cd caused oxidative stress via oxidation/antioxidation imbalance. Meanwhile, compared to the control group, T-help 17 (Th17) cell-related factors (IL-17, TNF-α, and RORγ) were up-regulated, regulatory T (Treg) cell-related factors (IL-10 and Foxp3) were down-regulated, and IL-17/IL-10, TNF-α/IL-10, and RORγ/Foxp3 were increased in Cd-exposed group; meaning that excess Cd induced immunosuppression via the imbalance of Th17/Treg cells. Taken together, our findings indicated that JNK-FoxO3a-PUMA pathway and mitochondrion participated in oxidative stress and immunosuppression-mediated apoptosis caused by Cd in common carp (Cyprinus carpio L.) gills. Our data provided new perspectives on the negative effects of heavy metal pollutants on fish.


Assuntos
Apoptose/efeitos dos fármacos , Cádmio/toxicidade , Carpas/metabolismo , Brânquias/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Brânquias/imunologia , Brânquias/metabolismo , Peróxido de Hidrogênio/metabolismo , Tolerância Imunológica/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Estresse Oxidativo/imunologia , Distribuição Aleatória
3.
Environ Toxicol Pharmacol ; 83: 103580, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33429071

RESUMO

Previous reports suggested that non-dioxin-like (NDL) PCB153 effects on cytochrome P450 3A (Cyp3a) expression in Atlantic killifish (Fundulus heteroclitus) gills differed between F0 generation fish from a PCB site (New Bedford Harbor; NBH) and a reference site (Scorton Creek; SC). Here, we examined effects of PCB153, dioxin-like (DL) PCB126, or a mixture of both, on Cyp3a56 mRNA in killifish generations removed from the wild, without environmental PCB exposures. PCB126 effects in liver and gills differed between populations, as expected. Gill Cyp3a56 was not affected by either congener in NBH F2 generation fish, but was induced by PCB153 in SC F1 fish, with females showing a greater response. PCB153 did not affect Cyp3a56 in liver of either population. Results suggest a heritable resistance to NDL-PCBs in killifish from NBH, in addition to that reported for DL PCBs. Induction of Cyp3a56 in gills may be a biomarker of exposure to NDL PCBs in fish populations that are not resistant to PCBs.


Assuntos
Citocromo P-450 CYP3A/biossíntese , Proteínas de Peixes/biossíntese , Fundulidae , Bifenilos Policlorados/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP3A/genética , Tolerância a Medicamentos , Indução Enzimática , Feminino , Proteínas de Peixes/genética , Fundulidae/genética , Fundulidae/metabolismo , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Receptor de Pregnano X/genética , RNA Mensageiro/metabolismo
4.
Environ Toxicol Pharmacol ; 83: 103596, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33482285

RESUMO

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.


Assuntos
Ciclídeos , Poluentes Químicos da Água/toxicidade , Acetilcolinesterase/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Brasil , Catalase/metabolismo , Ciclídeos/sangue , Ciclídeos/metabolismo , Feminino , Brânquias/efeitos dos fármacos , Brânquias/patologia , Glutationa Transferase/metabolismo , Gônadas/efeitos dos fármacos , Gônadas/patologia , Hidrocarbonetos Clorados/análise , Hidrocarbonetos Clorados/toxicidade , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Metais Pesados/análise , Metais Pesados/toxicidade , Músculos/efeitos dos fármacos , Músculos/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Carbonilação Proteica/efeitos dos fármacos , Rios , Vitelogeninas/sangue , Poluentes Químicos da Água/análise
5.
Environ Toxicol Pharmacol ; 83: 103597, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33493675

RESUMO

The purpose of this study was to confirm the limit of salinity tolerance in juvenile olive flounders (Paralichthys olivaceus) by changes in blood parameters, AChE, antioxidant and stress responses. The P. olivaceus (mean weight 38.8 ± 4.2 g and mean length 16.4 ± 1.2 cm) were exposed to different concentrations of salinity (seawater, 16, 8, 4, 2, and 0 psu) for 2 weeks. Plasma osmotic pressure was significantly decreased in the P. olivaceus at 0 psu. Hematological parameters such as hematocrit and hemoglobin were significantly decreased in the P. olivaceus at low salinity. Plasma components also changed significantly in the low salinity environment. As a stress indicator, cortisol was significantly increased at low salinity. SOD and GST antioxidant responses, were significantly increased. GSH level in the liver was significantly increased, whereas a significant decrease was observed in the gill GSH level. AChE was significantly increased in P. olivaceus at low salinity. The results of this study indicate that exposure to salinities lower than 8 psu leads to changes in hematological parameters, neurotransmitter, antioxidant and stress responses of P. olivaceus.


Assuntos
Linguado/metabolismo , Estresse Oxidativo , Salinidade , Acetilcolinesterase/metabolismo , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Animais , Aspartato Aminotransferases/sangue , Proteínas de Peixes/metabolismo , Linguado/sangue , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Glutationa/metabolismo , Glutationa Transferase/metabolismo , Hidrocortisona/sangue , Fígado/efeitos dos fármacos , Fígado/metabolismo , Superóxido Dismutase/metabolismo
6.
Ecotoxicol Environ Saf ; 208: 111601, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396121

RESUMO

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.


Assuntos
Atrazina/toxicidade , Characidae/metabolismo , Herbicidas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Atrazina/metabolismo , Relação Dose-Resposta a Droga , Feminino , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Herbicidas/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Testículo/efeitos dos fármacos , Testículo/metabolismo , Testículo/patologia , Poluentes Químicos da Água/metabolismo
7.
Ecotoxicol Environ Saf ; 208: 111603, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396123

RESUMO

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.


Assuntos
Corbicula/efeitos dos fármacos , Monitoramento Ambiental/métodos , Água Doce/química , Fungicidas Industriais/toxicidade , Nitrilos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/metabolismo , Catalase/metabolismo , Corbicula/enzimologia , Relação Dose-Resposta a Droga , Fungicidas Industriais/análise , Brânquias/efeitos dos fármacos , Brânquias/enzimologia , Glutationa Transferase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Nitrilos/análise , Poluentes Químicos da Água/análise
8.
Ecotoxicol Environ Saf ; 211: 111896, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33440267

RESUMO

Maduramicin, an extensively used anticoccidial drug, has been introduced into environment due to poorly absorbed in the intestine of broiler chicken. To understand the potential ecological toxicity of maduramicin on aquatic organisms, acute and subacute toxicity, hemolymph biochemistry, histopathology and the expressions of drug metabolism and stress response genes of crayfish (Procambius clarkii) were investigated in this study. For the first time, the 96 h median lethal concentration (LC50) of maduramicin on crayfish was 67.03 mgL-1 with a 95% confidence interval (54.06-81.32 mgL-1). Then, the crayfish were exposed to 0.7 mgL-1 (1/100 LC50), 3.5 mgL-1 (1/20 LC50) and 7.0 mgL-1 (1/10 LC50) maduramicin for 28 days. Maduramicin significantly altered biochemical parameters including AST, ALT, CK, LDH and ALP of hemolymph in crayfish at several time points. The activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) of crayfish gills, hepatopancreas and abdominal muscle were significantly decreased or elevated by different concentrations of maduramicin treatment at varying time points. Furthermore, histopathological damage of crayfish gills, hepatopancreas and abdominal muscle were observed in a concentration-dependent manner. The expressions of metabolic and stress response genes (CYP450, GST, COX1, COX2, HSP70 and MT) in hepatopancreas of crayfish were significantly up-regulated by maduramicin (7.0 mgL-1) treatment for 8 h to 7 d, and returned to normal levels after the removal of maduramicin for 3-7 days. In conclusion, our findings demonstrated that environmental exposure of maduramicin threaten to the health of crayfish living in the areas nearby livestock farms or pharmaceutical factory. Crayfish exhibited resistance to the stress of maduramicin via activating drug metabolite and detoxification pathways.


Assuntos
Antibacterianos/toxicidade , Astacoidea/fisiologia , Lactonas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Organismos Aquáticos/metabolismo , Astacoidea/efeitos dos fármacos , Catalase/metabolismo , Brânquias/efeitos dos fármacos , Glutationa Peroxidase/metabolismo , Hemolinfa/metabolismo , Hepatopâncreas/efeitos dos fármacos , Inativação Metabólica , Estresse Oxidativo/efeitos dos fármacos , Alimentos Marinhos , Superóxido Dismutase/metabolismo
9.
Ecotoxicol Environ Saf ; 208: 111645, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396165

RESUMO

The effects of chloridazon (Ch) and its metabolite chloridazon-desphenyl (Ch-D) at the environmentally relevant concentrations of 0.45 µg/L and 2.7 µg/L on signal crayfish Pacifastacus leniusculus were assessed in a 30-day exposure followed by a 15-day depuration period. Locomotion, biochemical haemolymph profile, oxidative and antioxidant parameters, and histopathology were evaluated. Crayfish exposed to Ch at 0.45 µg/L and 2.7 µg/L showed significantly (p < 0.01) higher CAT activity and GSH level in hepatopancreas and gill compared to controls. The concentration of Ch at 2.7 µg/L was associated with significantly (p < 0.01) higher levels of GLU, LACT, ALT, AST in haemolymph compared to controls. Chloridazon-desphenyl exposure at both tested concentrations caused significantly higher (p < 0.01) GLU, LACT, ALT, AST, NH3, and Ca in haemolymph; lipid peroxidation (TBARS) levels in hepatopancreas; and CAT activity and GSH level in hepatopancreas and gill. Alterations of structure including focal dilatation of tubules, increased number of fibrillar cells, and haemocyte infiltration in the interstitium were observed with 2.7 µg/L Ch and with both Ch-D exposures. Locomotion patterns did not vary significantly among groups. A 15-day recovery period was insufficient to restore normal physiological parameters in exposed groups. Chloridazon and its metabolite Ch-D exerts harmful effects on crayfish.


Assuntos
Astacoidea/efeitos dos fármacos , Herbicidas/toxicidade , Piridazinas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/metabolismo , Astacoidea/fisiologia , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Brânquias/patologia , Hemolinfa/citologia , Hemolinfa/efeitos dos fármacos , Hemolinfa/metabolismo , Hepatopâncreas/efeitos dos fármacos , Hepatopâncreas/metabolismo , Hepatopâncreas/patologia , Herbicidas/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Piridazinas/metabolismo , Poluentes Químicos da Água/metabolismo
10.
Ecotoxicol Environ Saf ; 208: 111765, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396084

RESUMO

Recent studies have shown that organisms including humans are exposed to microplastics directly or indirectly. The present study aims to examine the ingestion of these microplastics and the consequences of the same by studying the accumulation behavior of weathered Polyethylene (wPE) microplastics. The Perna viridis were exposed chronically to three different environmentally relevant concentrations of wPE for 30 days, followed by a one-week depuration phase. There was no mortality observed in the control and exposed groups, but the feeding rate was observed to have substantially decreased in the group exposed to higher concentration (3 µgL-1) of wPE. It was also observed that a higher number of wPE particles accumulated in the intestine of exposed organisms. Interestingly, the present study revealed the presence of the substantial number of wPE particles in exposed organisms, which may adversely affect the internal organs as well as growth and reproduction. This study perceived that accumulation is marginally influenced by size of wPE. Similarly, biomarker analysis showed that wPE exposure significantly altered both the metabolism and histology of the internal organs of the exposed organisms. Overall, the study confirmed that the intestine was the most sensitive organ followed by gills, adductor muscles, and foot tissue adding new insights into the adverse effects of wPE in the marine ecosystem.


Assuntos
Microplásticos/toxicidade , Perna (Organismo)/fisiologia , Polietileno/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Ecossistema , Ecotoxicologia , Brânquias/efeitos dos fármacos , Humanos , Microplásticos/metabolismo , Perna (Organismo)/efeitos dos fármacos , Plásticos , Polietileno/toxicidade , Alimentos Marinhos/análise , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
11.
Ecotoxicol Environ Saf ; 208: 111589, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396112

RESUMO

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.


Assuntos
Metais/toxicidade , Perna (Organismo)/fisiologia , Poluentes Químicos da Água/toxicidade , Animais , Baías , Brasil , Monitoramento Ambiental , Brânquias/efeitos dos fármacos , Glutationa/metabolismo , Metaloproteínas/metabolismo , Metalotioneína/metabolismo , Metais/análise , Metais/metabolismo , Perna (Organismo)/efeitos dos fármacos , Alimentos Marinhos/análise , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/metabolismo
12.
Ecotoxicol Environ Saf ; 208: 111617, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396137

RESUMO

Nitrate (NO3-), a potential toxic nitrogenous compound to aquatic animals, is distributed in aquatic ecosystems worldwide. The aim of this study was to investigate the effects of different NO3- levels on growth performance, health status, and endocrine function of juvenile turbot (Scophthalmus maximus) in recirculating aquaculture systems (RAS). Fish were exposed to 0 mg/L (control, CK), 50 mg/L (low nitrate, LN), 200 mg/L (medium nitrate, MN), and 400 mg/L (high nitrate, HN) NO3-N for 60 d in experimental RAS. Cumulative survival (CS) was significantly decreased with increasing NO3- levels in LN, MN, and HN. The lowest CS was 35% in the HN group. Growth parameters, including absolute growth rate, specific growth rate, and feed conversion rate, were significantly different in HN compared with that in the CK. Histological survey of gills and liver revealed dose-dependent histopathological damage induced by NO3- exposure and significant differences in glutamate pyruvate transaminase and glutamate oxalate transaminase in MN and HN compared with that in the CK. The hepatosomatic index in HN was significantly higher than that in the CK. Additionally, NO3- significantly increased bioaccumulation in plasma in LN, MN, and HN compared to that in the CK. Significant decreases in hemoglobin and increases in methemoglobin levels indicated reduced oxygen-carrying capacity in HN. Additionally, qRT-PCR and enzyme-linked immunosorbent assay (ELISA) were developed to investigate key biomarkers involved in the GH/IGF-1, HPT, and HPI axes. Compared with that in the CK, the abundance of GH, GHRb, and IGF-1 was significantly lower in HN, whereas GHRa did not differ between treatments. The plasma T3 level significantly decreased in LN, MN, and HN and T4 significantly decreased in HN. The CRH, ACTH, and plasma cortisol levels were significantly upregulated in HN compared with that in the CK. We conclude that elevated NO3- exposure leads to growth retardation, impaired health status, and endocrine disorders in turbot and the NO3- level for juvenile turbot culture should not exceed 50 mg/L NO3-N in RAS. Our findings indicate that endocrine dysfunction of the GH/IGF-1, HPT, and HPI axes might be responsible for growth inhibition induced by NO3- exposure.


Assuntos
Aquicultura/métodos , Sistema Endócrino/efeitos dos fármacos , Linguados/crescimento & desenvolvimento , Nitratos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Ecossistema , Sistema Endócrino/metabolismo , Brânquias/efeitos dos fármacos , Brânquias/patologia , Nível de Saúde , Fígado/efeitos dos fármacos , Fígado/patologia , Alimentos Marinhos , Hormônios Tireóideos/metabolismo
13.
Aquat Toxicol ; 230: 105716, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33310673

RESUMO

To obtain a deeper understanding of the transcriptomic responses to oil in southern flounder (Paralichthys lethostigma), we performed quantitative PCR and RNA sequencing on liver and gill tissue after a chronic exposure (35 days) to Deepwater Horizon crude oiled sediment and after a 30-day recovery period. We wanted to understand which specific genes are differentially expressed in liver and gill tissues directly after oiled sediment exposure and with the addition of a recovery period. Furthermore, we wanted to examine specific enriched pathways in these two tissues to determine the impact of exposure with and without a recovery period on biological processes (e.g. immune function). Liver and gill tissues were chosen because they represent two distinct organs that are highly important to consider when examining the impacts of oiled sediment exposure. The liver is the classic detoxification organ, while the gill is in direct contact with sediment in benthic fishes. Examination of these two tissues, therefore, generates a broad understanding of the transcriptomic consequences of oil exposure across an organism. Gene expression for interleukin 8 (il8) and interleukin 1B (il1ß) was significantly increased versus control measurements for fish exposed to oiled sediments for 35 days in gill tissue. Hierarchical clustering of gene expression showed that tissue type was the main driver of gene expression (rather than treatment). The inclusion of a 30-day post-exposure recovery period showed a return of il8 and il1ß gene expression in the gill to baseline expression levels. However, the recovery period increased the number of differentially expressed genes and significantly affected canonical pathways in both tissue types. Pathways related to cholesterol biosynthesis were significantly suppressed in oil-exposed flounder with a recovery period, but not in the exposed flounder without a recovery period. At the end of the exposure, 17 pathways were significantly affected in the gill, including thyroid hormone metabolism-related pathways, which were the most influenced. Liver tissue from the recovered fish had the greatest number of enriched pathways for any tissue or time point (187). Cellular and humoral immune response pathways were considerably impacted in the liver after the recovery period, suggesting that the immune system was attempting to respond to potential damage caused from the chronic oil exposure. Our results demonstrate that liver and gill tissues from southern flounder were differentially altered by Deepwater Horizon oiled sediment exposure and that a 30-day recovery period after exposure substantially shifted gene expression and canonical pathway profiles.


Assuntos
Linguado/genética , Sedimentos Geológicos/química , Poluição por Petróleo/efeitos adversos , Petróleo/toxicidade , Transcriptoma/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Biologia Computacional , Brânquias/química , Brânquias/efeitos dos fármacos , Golfo do México , Fígado/química , Fígado/efeitos dos fármacos
14.
Aquat Toxicol ; 230: 105704, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33316749

RESUMO

Recurrent dinoflagellate blooms of Alexandrium catenella expose the economically and ecologically important Southern Rock Lobster in Tasmania to paralytic shellfish toxins (PST), and it is unknown if PST accumulation adversely affects lobster performance, health and catchability. In a controlled aquaculture setting, lobsters were fed highly contaminated mussels to accumulate toxin levels in the hepatopancreas (mean of 6.65 mg STX.2HCl equiv. kg-1), comparable to those observed in nature. Physiological impact of PST accumulation was comprehensively assessed by a range of behavioural (vitality score, righting ability and reflex impairment score), health (haemocyte count, bacteriology, gill necrosis and parasite load), nutritional (hepatopancreas index and haemolymph refractive index) and haemolymph biochemical (21 parameters including electrolytes, metabolites, and enzymes) parameters during a 63 day period of uptake and depuration of toxins. Exposure to PST did not result in mortality nor significant changes in the behavioural, health, or nutritional measures suggesting limited gross impact on lobster performance. Furthermore, most haemolymph biochemical parameters measured exhibited no significant difference between control and exposed animals. However, the concentration of potassium in the haemolymph increased with PST, whilst the concentration of lactate and the sodium:potassium ratio decreased with PST. In addition, exposed lobsters showed a hyperglycaemic response to PST exposure, indicative of stress. These findings suggest that PST accumulation results in some measurable indicators of stress for lobsters. However, these changes are likely within the adaptive range for Jasus edwardsii and do not result in a significant impairment of gross performance. Our findings support previous conclusions that crustaceans are relatively tolerant to PST and the implications for the lobster fishery are discussed.


Assuntos
Bioacumulação/efeitos dos fármacos , Palinuridae/metabolismo , Saxitoxina/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Bivalves/metabolismo , Dinoflagelados/metabolismo , Cadeia Alimentar , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Hemócitos/efeitos dos fármacos , Hemócitos/metabolismo , Hemolinfa/metabolismo , Hepatopâncreas/efeitos dos fármacos , Hepatopâncreas/metabolismo , Saxitoxina/metabolismo , Frutos do Mar , Austrália do Sul , Poluentes Químicos da Água/metabolismo
15.
Aquat Toxicol ; 230: 105688, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33316748

RESUMO

Organophosphate flame retardants (OPFRs) are (re-)emergent environmental pollutants increasingly being used because of the restriction of other flame retardants. The chlorinated OPFR, tris(1,3-dichloro-2-propyl) phosphate (TDCPP) is among those of highest environmental concern, but its potential effects in the marine environment have rarely been investigated. We exposed a widely used sentinel marine mussel species, Mytilus galloprovincialis, to 10 µg L-1 of TDCPP during 28 days and studied: (i) the kinetics of bioaccumulation and elimination of the compound, (ii) the effect on two molecular biomarkers, glutathione S-transferase (GST) and acetylcholinesterase (AChE) activities, and (iii) proteomic alterations in the gills, following an isobaric labeling quantitative shotgun proteomic approach, at two exposure times (7 and 28 days). Uptake and elimination of TDCPP by mussels were very fast, and the bioconcentration factor of this compound in mussels was 147 L kgww-1, confirming that this compound is not very bioaccumulative, as predicted by its chemical properties. GST activity was not affected by TDCPP exposure, but AChE activity was inhibited by TDCPP at both 7 and 28 days of exposure. Proteomic analysis revealed subtle effects of TDCPP in mussel gills, since few proteins (less than 2 % of the analysed proteome) were significantly affected by TDCPP, and effect sizes were low. The most relevant effects detected were the up-regulation of epimerase family protein SDR39U1, an enzyme that could be involved in detoxification processes, at both exposure times, and the down-regulation of receptor-type tyrosine-protein phosphatase N2-like (PTPRN2) after 7 days of exposure, which is involved in neurotransmitter secretion and might be related to the neurotoxicity described for this compound. Exposure time rather than TDCPP exposure was the most important driver of protein abundance changes, with 33 % of the proteome being affected by this factor, suggesting that stress caused by laboratory conditions could be an important confounding factor that needs to be controlled in similar ecotoxicology studies. Proteomic data are available via ProteomeXchange with identifier PXD019720.


Assuntos
Bioacumulação/efeitos dos fármacos , Retardadores de Chama/toxicidade , Brânquias/metabolismo , Mytilus/efeitos dos fármacos , Compostos Organofosforados/toxicidade , Poluentes Químicos da Água/toxicidade , Acetilcolinesterase/metabolismo , Animais , Biomarcadores/metabolismo , Relação Dose-Resposta a Droga , Retardadores de Chama/metabolismo , Brânquias/efeitos dos fármacos , Glutationa Transferase/metabolismo , Cinética , Modelos Biológicos , Mytilus/metabolismo , Compostos Organofosforados/metabolismo , Proteômica , Poluentes Químicos da Água/metabolismo
16.
Ecotoxicol Environ Saf ; 207: 111560, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33254414

RESUMO

Fullerene C60 (FC60), with its unique physical properties, has been used in many applications in recent decades. The increased likelihood of direct release into the environment has raised interest in understanding the biological effects of FC60 to aquatic organisms. Nowadays, only few studies have analysed FC60 effects and bioaccumulation in marine organisms following in vivo exposure. To provide new data about FC60 toxicity, Ruditapes philippinarum was selected as target species to assess potential adverse effects of the contaminant. Clams were exposed for 1, 3 and 7 days to predicted environmental concentrations of FC60 (1 and 10 µg/L) and cellular and biochemical responses were evaluated in clams' gills, digestive gland and haemolymph. The FC60 content in gills and digestive gland was determined in all experimental conditions after 7 days of exposure. Results showed an increase in oxidative stress. In particular, a significant modulation in antioxidant enzyme activities, and changes in glutathione S-transferase activity were observed in gills. Moreover, damage to lipids and proteins was detected in FC60-treated (10 µg/L) clams. In digestive gland, slighter variations in antioxidant enzyme activities and damage to molecules were detected. CAT activity was significantly affected throughout the exposure, whereas damage to lipids was evident only at the end of exposure. FC60 accumulation was revealed in both gills and digestive gland, with values up to twelve-fold higher in the latter. Interestingly, haemolymph parameters were slightly affected by FC60 compared to the other tissues investigated. Indeed, only Single Cell Gel Electrophoresis and Neutral Red uptake assays showed increased values in FC60-exposed clams. Moreover, volume and diameter of haemocytes, haemocyte proliferation, and micronucleus assay highlighted significant variations in treated clams, but only in the first phases of exposure, and no changes were detected after 7 days. Our results suggested clam gills as the target tissue for FC60 toxicity under the exposure conditions tested: the high damage detected to lipids and proteins could contribute to long-term problems for the organism.


Assuntos
Bivalves/fisiologia , Fulerenos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/metabolismo , Bioacumulação , Biomarcadores/metabolismo , Bivalves/efeitos dos fármacos , Fulerenos/metabolismo , Brânquias/efeitos dos fármacos , Hemolinfa/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Alimentos Marinhos/análise
17.
Artigo em Inglês | MEDLINE | ID: mdl-33356853

RESUMO

Cadmium (Cd) toxic effects can overwhelm endogenous antioxidants and affect recuperation in fish. Thus, this study assessed antioxidative properties and ameliorating potentials of dietary supplemented garlic (D1), propolis (D2), and wakame (D3) on i) Cd bioconcentration, and ii) Cd induced toxicity during recuperation in Cd exposed Japanese medaka. In a 21-day exposure, control (0.0 mg Cd/L in water-C1) or Cd-treatment (0.3 mg Cd/L in water-T1) fish were fed medaka diets. Surviving fish in T1 were further depurated for 21-days and fed D1, D2, D3, or medaka diet (C2). Gill, liver, and muscle tissues were assessed weekly for Cd bioconcentration, metallothionein, (MT), superoxide dismutase (SOD), total glutathione (GSH), and lipid peroxidation (LPO). Results showed reduced antioxidant activity by significantly increasing tissue Cd and LPO, and significantly reducing SOD activity and GSH content in gill and muscle upon Cd exposure. In contrast, D1, D2, and D3 diets significantly reduced tissue Cd and LPO, while increasing contents of MT and GSH, and SOD activity, significantly. Other condition indices in D1, D2 and D3 groups were also significantly higher than those in C2 groups. In conclusion, dietary supplementation significantly increased recuperation and tissue functions in fish, in the order D1 > D2 > D3> C2.


Assuntos
Ração Animal , Cádmio/toxicidade , Alho/química , Oryzias/metabolismo , Própole/química , Undaria/química , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/metabolismo , Catalase/metabolismo , Dieta , Suplementos Nutricionais , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Glutationa/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Superóxido Dismutase/metabolismo
18.
Environ Toxicol Pharmacol ; 82: 103555, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33309951

RESUMO

Several studies highlight the presence of aluminum and diclofenac in water bodies around the world and their ability to induce oxidative stress and a negative effect on biomolecules in several aquatic species. However, studies evaluating the toxic effect of mixtures of these contaminants are scarce. The objective of this work was to determine the genotoxic, cytotoxic and embryotoxic effect of the mixture of aluminum and diclofenac at environmentally relevant concentrations on Cyprinus carpio. Juveniles of Cyprinus carpio were exposed to 0.31 µg L-1 of diclofenac, 24.45 mg L-1 of aluminum, and a mixture of both contaminants at the same concentrations for 12, 24, 48, 72 and 96 h. After the exposure time the liver, gills and blood were extracted and the following biomarkers were evaluated: micronucleus frequency, comet assay, caspase activity and TUNEL test. On the other hand, Cyprinus carpio embryos were exposed to diclofenac (0.31 µg L-1), aluminum (0.06 mg L-1) and their mixture at the same concentrations and exposure time. Microscopic observation was performed to evaluate embryonic development at 12, 24, 48, 72 and 96 h. Diclofenac (0.31 µg L-1) induces significant increases in micronucleus frequency with respect to control (p < 0.05), in all tissues. Aluminum (24.45 mg L-1) significantly increases DNA damage index in liver and blood cells with respect to control (p < 0.05). All treatments increase caspases activity in all tissues with respect to control (p < 0.05). Diclofenac increases the percentage of TUNEL-positive cells in liver and blood; while aluminum and the mixture increases it significantly in gills and blood with respect to the control (p < 0.05). The mixture significantly delays embryonic development, while aluminum and the mixture significantly increase teratogenic index with respect to control (p < 0.05). In conclusion, exposure to environmental concentrations of aluminium, diclofenac and their mixture induces genotoxic damage, cell death by apoptosis and negative effects on the development of Cyprinus carpio and the toxic response is modified by the interaction of the xenobiotics.


Assuntos
Alumínio/toxicidade , Carpas , Diclofenaco/toxicidade , Mutagênicos/toxicidade , Teratogênios/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Células Sanguíneas/efeitos dos fármacos , Carpas/embriologia , Carpas/genética , Carpas/metabolismo , Caspase 3/metabolismo , Ensaio Cometa , Dano ao DNA , Interações Medicamentosas , Desenvolvimento Embrionário/efeitos dos fármacos , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Testes para Micronúcleos
19.
Chemosphere ; 262: 128290, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33182139

RESUMO

Tumble dryer lint has been employed as a surrogate for synthetic and processed (microplastic) fibres discharged to the environment from laundering activities and exposed to marine mussels (Mytilus galloprovinciallis) in controlled experiments for a period of 7 d. A range of biological responses at different levels of organisation were subsequently determined, with copper employed concurrently as a positive control. Physiological changes were assessed from measurements of clearance rate, histopathological effects were evaluated from abnormalities in (or injuries to) gill and digestive gland tissues, and genetic damage was determined by measuring DNA strand breaks using the comet assay. With increasing lint concentration (over the range 56-180 mg L-1) we observed a reduction in mean clearance rate, increasing extents of abnormality in both gills (e.g. deciliation and hypertrophy) and digestive gland (e.g. atrophy and necrosis), and an increase in damage to DNA. The precise causes of these effects are unclear but likely arise from both the fibrous material itself and from chemicals (e.g. additives and metals) that are mobilised from the polymers into seawater or the digestive tract. The latter assertion is consistent with an observed increase in the release of certain trace elements (e.g. zinc) into the exposure medium with increasing lint concentration. Although microfibre concentrations we employed are significantly greater than those typically encountered in the environment, the results indicate the potential for this type of material to exert a range of adverse effects on exposed marine animals.


Assuntos
Dano ao DNA , Microplásticos/toxicidade , Mytilus/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Ensaio Cometa , Cobre/toxicidade , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Hemolinfa/efeitos dos fármacos , Hemolinfa/metabolismo , Taxa de Depuração Metabólica , Modelos Teóricos , Mytilus/genética , Mytilus/metabolismo , Água do Mar/química
20.
Ecotoxicol Environ Saf ; 207: 111286, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32931973

RESUMO

Azoxystrobin (AZX) is a broad-spectrum systemic fungicide massively used worldwide. Its mode of action consists in the inhibition of mitochondrial respiration decreasing the synthesis of ATP and leading to oxidative stress in the target fungus. However, whether this effect occurs in non target organisms has been scarcely studied. The objectives of this work were (1) to evaluate biomarkers of oxidative stress, hematological, physiological and of genotoxicity in the native cichlid fish Australoheros facetus exposed to environmentally relevant concentrations of AZX and (2) to compare these biomarkers in different developmental stages using juvenile and adult fish (n = 6) exposed during 48 h. The exposure concentrations were 0 (negative control, C (-)), 0.05, 0.5, 5 and 50 µg/L AZX of the commercial formulation AMISTAR®. Blood was drawn to evaluate hematology, and DNA damage through the comet assay (CA) and micronucleus test (MN). Genotoxicity was observed by mean of both biomarkers in juvenile and adult fish at 50 µg/L AZX. Samples of liver and gills were used to determine antioxidant enzymes activity, hydrogen peroxide (H2O2) and malondialdehyde (MDA) contents. In juvenile fish inhibition of superoxide dismutase (SOD) was observed in liver at 0.05, 5 and 50 µg/L AZX and in gills at 5 and 50 µg/L AZX. Glutathione- S- transferases (GST) activity increased in gills at all AZX concentrations tested. In adult fish, increase of hepatic catalase (CAT) activity at 0.5 and 50 µg/L AZX and MDA content at 50 µg/L AZX were observed. In gills only H2O2 content showed changes at 50 µg/L AZX. The sensitivity showed by gills constitutes the first report about AZX toxicity in this organ. All these negative effects were observed in the range of realistic AZX concentrations, which warns of the possible consequences that it may have on the health of aquatic biota. Differences between juvenile and adult fish demonstrate the relevance of considering the developmental stage on the evaluation of biomarkers.


Assuntos
Ciclídeos/sangue , Dano ao DNA , Fungicidas Industriais/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Pirimidinas/toxicidade , Estrobilurinas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/sangue , Catalase/metabolismo , Ciclídeos/genética , Ensaio Cometa , Fungicidas Industriais/análise , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Hematologia , Peróxido de Hidrogênio/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Pirimidinas/análise , Estrobilurinas/análise , Superóxido Dismutase/metabolismo , Poluentes Químicos da Água/análise
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