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1.
J Photochem Photobiol B ; 198: 111552, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31382089

RESUMO

A 58-day cultivation experiment was carried out to investigate the effects of photoperiods on growth, lipid metabolism and oxidative stress of juvenile gibel carp. Juveniles (5.41 ±â€¯0.01 g) were cultured under seven light photoperiods (0 h of light (L):24 h of darkness (D), 4L:20D (12:00-16:00 light), 8L:16D (10:00-18:00 light), 12L:12D (8:00-20:00 light), 16L:8D (6:00-22:00 light), 20L:4D (4:00-24:00 light) and 24L:0D) in an indoor recirculating aquaculture system. The light intensity was 1.02 µmol·m-2·s-1 (at the tank bottom in a 0.5-m water depth). The fish were fed to satiety three times daily (8:30, 14:30 and 18:30). At the end of the experiment, final body weight, specific growth rate, feed efficiency and feed intake were significantly higher in 16L:8D, 20L:4D and 24L:0D groups than those in other groups (P < 0.05). Long-day photoperiods (16L:8D, 20L:4D and 24L:0D) simultaneously promoted lipogenesis, lipolysis and fatty acid oxidation. The increases in lipid retention efficiency, whole body lipid concentration and liver lipid content (P < 0.05) indicated that lipogenesis exceeded fatty acid oxidation. Liver oxidative stress was induced in juvenile gibel carp by short day lengths. The hepatic total antioxidant capacity, superoxide dismutase, glutathione peroxidase and the contents of metabolite glutathione were the highest in the short-day-length groups (0L:24D, 4L:20D and 8L:16D) (P < 0.05). Based on the growth performance and health status in the long-term cultivation experiment, the optimal photoperiods were 16L:8D, 20L:4D and 24L:0D in juvenile gibel carp.


Assuntos
Carpa Dourada/metabolismo , Metabolismo dos Lipídeos , Estresse Oxidativo , Animais , Peso Corporal , Ingestão de Alimentos , Glutationa , Glutationa Peroxidase , Carpa Dourada/crescimento & desenvolvimento , Fígado/metabolismo , Fotoperíodo , Superóxido Dismutase/metabolismo
2.
Ecotoxicol Environ Saf ; 183: 109501, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31401330

RESUMO

17α-ethynylestradiol (EE2), a ubiquitous synthetic endocrine disrupting chemical, was the principal component of contraceptive drugs and one of common hormone medications. The detrimental impact of EE2 on the reproduction of organisms was widely recognized. However, the underlying mechanisms of physiological and metabolome effects of EE2 on freshwater fish are still unclear. This study investigated the toxic effects and related mechanisms of EE2 on freshwater fish crucian carp (Carassius auratus) based on metabolomics. Crucian carp were exposed to EE2 at environmentally relevant concentration for 9 days, 18 days, and 27 days, and the biological responses were explored through analysis of the physiological endpoints, steroid hormones, and metabolome. The physiological endpoints of crucian carp had no distinct change after EE2 exposure. However, metabolomics analysis probed significant deviation based on chemometrics, indicating that the metabolomics approach was more sensitive to the effects of EE2 at environmentally relevant concentration to freshwater fish than the traditional endpoints. The alterations of 24 metabolites in gonad and 16 metabolites in kidney were induced by treatment with EE2, respectively, which suggesting the perturbations in amino acid metabolism, lipid metabolism, energy metabolism, and oxidative stress. Moreover, EE2 exposure could induce the disruption of lipid metabolism and then broke the homeostasis of endogenous steroid hormones. Metabolomics provided a new strategy for the studies on contaminant exposure at a low dose in the short term and gave important information for the toxicology and mechanism of EE2.


Assuntos
Disruptores Endócrinos/toxicidade , Etinilestradiol/toxicidade , Carpa Dourada/metabolismo , Metaboloma/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Exposição Ambiental/efeitos adversos , Metabolômica , Reprodução/efeitos dos fármacos , Esteroides/metabolismo
3.
J Agric Food Chem ; 67(25): 7174-7182, 2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31240931

RESUMO

Intake of endocrine-disrupting chemicals (EDCs) by humans could disturb the metabolism of hormones, induce cancer, and damage the liver and other organs. Phthalate acid esters (PAEs) and alkylphenols (APs) are important EDCs and environmental contaminants. With the increasing use of plastics and nonionic surfactants worldwide, PAEs and APs have entered environmental water and accumulated in edible fish, which are finally consumed by humans. In this study, a coated direct inlet probe (CDIP) based on an atmospheric solid analysis probe, which can rapidly and simultaneously extract both PAEs and APs in fish, was developed. Twelve PAEs and APs were quantified by using a stable-isotope-labeled internal standard. Standard curves of the PAEs and APs having correlation coefficients of R2 ≥ 0.9837 were obtained. The limit of detection of the PAEs and APs was distributed from 0.01 to 40 ng g-1. The relative recovery of the method was 78-120% between low, medium, and high spiked levels. Combined with principal component analysis, PAE- and AP-contaminated Carassius auratus from different habitats could be identified. Multiple sample analysis mode allowed the extraction of up to 12 samples at once, and the total analysis time (including sample pretreatment, extraction, and analysis time) was less than 10 min per sample, which indicates that CDIP is useful for rapid quantitative analysis.


Assuntos
Ésteres/análise , Carpa Dourada , Ensaios de Triagem em Larga Escala/métodos , Fenóis/análise , Ácidos Ftálicos/análise , Animais , Disruptores Endócrinos/análise , Disruptores Endócrinos/isolamento & purificação , Ésteres/isolamento & purificação , Carpa Dourada/metabolismo , Ensaios de Triagem em Larga Escala/instrumentação , Limite de Detecção , Fenóis/isolamento & purificação , Ácidos Ftálicos/isolamento & purificação , Extração em Fase Sólida
4.
Artigo em Inglês | MEDLINE | ID: mdl-31176866

RESUMO

Cysteine oxygenase (CDO) is a mononuclear nonhemoglobin enzyme that catalyzes the production of taurine through the cysteine (Cys) pathway and plays a key role in the biosynthesis of taurine in mammals. However, the function of CDOs in bony fish remains poorly understood. In this study, we cloned CDO genes (CaCDO1 and CaCDO2) from Carassius auratus. The cDNA sequences of both CaCDO1 and CaCDO2 encoded putative proteins with 201 amino acids, which included structural features typical of the CDO protein family. Multiple sequence alignment and phylogenetic analysis showed that CaCDO1 and CaCDO2 shared high sequence identities and similarities with C. carpio homologs. Quantitative real-time polymerase chain reaction (qRT-PCR) results revealed that CaCDO1 and CaCDO2 were both broadly expressed in all selected tissues and developmental stages in C. auratus but had differing mRNA levels. In addition, compared to those of the taurine-free group, the in vivo mRNA expression levels of both CaCDO1 and CaCDO2 significantly decreased with increasing dietary taurine levels from 1.0 to 9.0 g/kg. Furthermore, in vitro taurine treatments showed similar inhibitory effects on the expression of CaCDO1 and CaCDO2 in the intestines of C. auratus. Our results also showed that the mRNA expression of CaCDO2 in the intestines was higher than that of CaCDO1 in response to in vivo and in vitro taurine supplementation. Overall, these data may provide new insights into the regulation of fish CDO expression and provide valuable knowledge for improving dietary formulas in aquaculture.


Assuntos
Cisteína Dioxigenase/genética , Cisteína Dioxigenase/metabolismo , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Carpa Dourada/genética , Carpa Dourada/metabolismo , Taurina/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA Complementar/genética , Regulação da Expressão Gênica no Desenvolvimento , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Carpa Dourada/crescimento & desenvolvimento , Isoenzimas/genética , Isoenzimas/metabolismo , Filogenia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Taurina/farmacologia , Distribuição Tecidual
5.
Sci Total Environ ; 659: 540-547, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31096383

RESUMO

Mercury is a potentially toxic trace metal that poses threats to aquatic life and to humans. In this study, a mercury-binding peptide was displayed on the surface of Escherichia coli cells using an N-terminal region ice nucleation protein anchor. The surface-engineered E. coli facilitated selective adsorption of mercury ions (Hg2+) from a solution containing various metal ions. The Hg2+ adsorption capacity of the surface-engineered cell was four-fold higher than that of the original E. coli cells. Approximately 95% of Hg2+ was removed from solution by these whole-cell sorbents. The transformed strains were fed to Carassius auratus, so that the bacteria could colonize fish intestine. Engineered bacteria-fed C. auratus showed significantly less (51.1%) accumulation of total mercury when compared with the group that had not been fed engineered bacteria. The surface-engineered E. coli effectively protected fish against the toxicity of Hg2+ in aquatic environments by adsorbing more Hg2+. Furthermore, the surface-engineered E. coli mitigated microbial diversity changes in the intestine caused by Hg2+ exposure, thereby protecting the intestinal microbial community. This strategy is a novel approach for controlling Hg2+ contamination in fish.


Assuntos
Membrana Celular/metabolismo , Proteínas de Escherichia coli/metabolismo , Carpa Dourada/metabolismo , Mercúrio/metabolismo , Peptídeos/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Animais Geneticamente Modificados/metabolismo , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Engenharia Genética , Mucosa Intestinal/metabolismo , Microrganismos Geneticamente Modificados/genética , Peptídeos/genética
6.
Fish Physiol Biochem ; 45(3): 921-933, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31104250

RESUMO

In fish, as in mammals, several studies have demonstrated that the cocaine- and amphetamine-regulated transcript (CART) plays an important role in feeding. However, thus far, the function of CART in gibel carp (Carassius auratus gibelio) feeding regulation has not been reported. In our study, we first identified three forms of CART peptide precursors from gibel carp brain and named these CART-1, CART-2, and CART-3. The full-length cDNA sequences of CART-1, CART-2, and CART-3 were 616 bp, 705 bp, and 760 bp, respectively, encoding peptides of 118, 120, and 104 amino acid residues. We detected mRNA expression of CART-1, CART-2, and CART-3 in a wide range of peripheral and central tissues, with the highest expression detected in the brain. After a meal, mRNA expression of CART-1, CART-2, and CART-3 was significantly elevated, suggesting that CART-1, CART-2, and CART-3 may act as postprandial satiety signals. Moreover, mRNA expression of all three CART-1, CART-2, and CART-3 was significantly reduced during fasting and significantly elevated with refeeding. Our findings indicate that CART-1, CART-2, and CART-3 might function as a satiety factor in the gibel carp.


Assuntos
Comportamento Alimentar/fisiologia , Carpa Dourada/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Regulação da Expressão Gênica , Proteínas do Tecido Nervoso/genética , Filogenia , Isoformas de Proteínas
7.
Artigo em Inglês | MEDLINE | ID: mdl-31075982

RESUMO

Ofloxacin, sulfamethoxazole and ibuprofen are three commonly used drugs which can be detected in aquatic environments. To assess their ecotoxicity, the effects of these three pharmaceuticals and their mixture on AChE (acetylcholinesterase) activity in the brain, and EROD (7-ethoxyresorufin-O-deethylase) and SOD (superoxide dismutase) activities in the liver of the freshwater crucian carp Carassius auratus were tested after exposure for 1, 2, 4 and 7 days. The results showed that treatments with 0.002⁻0.01 mg/L ofloxacin and 0.0008⁻0.004 mg/L sulfamethoxazole did not significantly change AChE, EROD and SOD activities. AChE activity was significantly inhibited in response to treatment with 0.05mg/L ofloxacin and 0.02mg/L sulfamethoxazole. All three biomarkers were induced significantly in treatments with ibuprofen and the mixture of the three pharmaceuticals at all the tested concentrations. The combined effects of ofloxacin, sulfamethoxazole and ibuprofen were compared with their isolated effects on the three biomarkers, and the results indicated that exposure to ibuprofen and the mixture at environmentally relevant concentrations could trigger adverse impacts on Carassius auratus. The hazard quotient (HQ) index also demonstrated a high risk for ibuprofen. Moreover, the present study showed that the effects of ofloxacin, sulfamethoxazole and ibuprofen might be additive on the physiological indices of Carassius auratus.


Assuntos
Carpa Dourada/metabolismo , Ibuprofeno/toxicidade , Ofloxacino/toxicidade , Sulfametoxazol/toxicidade , Poluentes Químicos da Água/toxicidade , Acetilcolinesterase/metabolismo , Animais , Biomarcadores/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Interações de Medicamentos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Superóxido Dismutase/metabolismo
8.
Sci Total Environ ; 653: 1395-1406, 2019 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-30759578

RESUMO

Perfluorooctanoic acid (PFOA) has long been produced and widely used due to its excellent water and oil repellent properties. However, this trend has facilitated to the ubiquitous existence of PFOA in environmental matrix, and the potential ecotoxicity on aquatic organisms has not been fully elucidated. To study the tissue-specific bioconcentration and the nervous system- and energy-related biochemical effects of PFOA, as well as the phenotypic alterations by this chemical, male crucian carp (Carassius auratus) were exposed to gradient concentrations of PFOA (nominal 0.2, 10, 500 and 25,000 µg/L) in a flow-through apparatus for 7 days. PFOA was enriched in tissues following an order of blood > kidney ≥ liver > gill > brain > muscle. The bioconcentration factors ranged from 0.1 to 60.4. Acetylcholinesterase activity in the fish brain was inhibited, while liver carboxylesterase was induced in most cases and attenuated with time. The acyl-CoA oxidase activity was dose-dependently elevated and accompanied by a decline of ATP contents. PFOA treatments also inhibited the activity of the electron transport system (ETS). At the transcriptional level, ETS component complexes II and IV were concordantly depressed, and ATP synthesis was also downregulated. The mRNA level of peroxisome proliferator activated receptor α was increasingly upregulated, with related downstream genes upregulated in varying degrees. The phenotypes showed patterns of increased liver pathology and reduced swimming activity. In summary, PFOA leads to adverse effects in Carassius auratus related to multiple aspects, which may be associated with the nervous system, fundamental energy metabolism and other unpredictable factors. The results obtained in this study are expected to help clarify the PFOA toxic mechanisms on energy relevance.


Assuntos
Caprilatos/metabolismo , Fluorcarbonetos/metabolismo , Carpa Dourada/metabolismo , Animais , Caprilatos/toxicidade , Fluorcarbonetos/toxicidade , Expressão Gênica/efeitos dos fármacos , Perfilação da Expressão Gênica , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Mitocôndrias/efeitos dos fármacos , Peroxissomos/efeitos dos fármacos , Peroxissomos/metabolismo , Peroxissomos/fisiologia , Fenótipo
9.
Aquat Toxicol ; 209: 159-167, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30780113

RESUMO

The expression of estrogen receptors (ERs) and their roles in important cell processes such as apoptosis in the macrophages exposed to estrogen/xenoestrogen have remained a complex secret. This study focused on the expression of estrogen receptors (ERs) and the stimulation of apoptosis in the macrophages from the two sexes of goldfish (Carassius auratus) exposed to 17-ßestradiol (E2) and nonylphenol (NP) under in vivo and in vitro conditions. For the in vivo experiment, fish were exposed to NP (10-6 M and 10-7 M) and E2 (10-6 M) for 24 days. Then, the head kidney macrophages from the male and the female goldfish were isolated and assayed. For the in vitro experiments, the macrophages derived from the two sexes were cultured in L-15 medium and exposed to E2 (150 nM) and NP (10 nM and 150 nM) for 3 days. The results showed that the three isoforms of ERs (ERα, ERß1, ERß2) were expressed in the goldfish macrophages. After the exposure of macrophages to NP and E2, sex-specific increase of ERs expression and apoptosis were observed (P < 0.05). The expression of ERα after NP treatment showed the highest alteration, with the response being concentration-dependent. The most alteration of ERs expression were observed in the in vivo experiment. This study provides insight to understand how exposure of the goldfish macrophages to E2 and NP can up-regulate the transcript levels of estrogen receptor subtypes and stimulate apoptosis.


Assuntos
Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/metabolismo , Estrogênios/toxicidade , Carpa Dourada/metabolismo , Macrófagos/metabolismo , Modelos Biológicos , Fenóis/toxicidade , Animais , Apoptose/efeitos dos fármacos , Células Cultivadas , Receptor alfa de Estrogênio/genética , Receptor beta de Estrogênio/genética , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Carpa Dourada/genética , Macrófagos/efeitos dos fármacos , Masculino , Testes de Toxicidade , Poluentes Químicos da Água/toxicidade
10.
Chemosphere ; 221: 235-245, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30640006

RESUMO

Bisphenol A (BPA) is an abundant endocrine-disrupting compound that is found in the aquatic environment and has adverse effects on fish reproduction; however, the exact pathway of these impacts is unclear. In this study, the different effects of BPA on ovarian and testis development in goldfish (Carassius auratus) and the different mechanisms underlying these effects were investigated. The gonadosomatic index (GSI) and gonadal histology demonstrated that BPA diminished ovarian maturation in goldfish, which recovered after BPA treatment withdrawal. In males, BPA disrupted testis maturation, but this disruption could not be recovered after BPA treatment withdrawal. The hypothalamic-pituitary-gonad (HPG) axis-related genes sgnrh, fshß and lhß were significantly decreased in BPA-treated female fish, while no changes in sex steroid hormone levels and no TUNEL and PCNA staining were found in the ovary, suggesting that BPA may reduce ovarian maturation through the HPG axis. In male fish, TUNEL staining was found in 1 µg L-1 BPA-exposed germ cells and 50 and 500 µg L-1 BPA-exposed Leydig cells. Decreases in 11-KT levels were also found in 50 and 500 µg L-1 BPA-exposed fish, but BPA did not affect genes associated with the HPG axes. This result shows that BPA disrupts testis maturation through apoptosis of germ cells and Leydig cells, thus inducing decreases in 11-KT levels that disrupt spermatogenesis. Collectively, our findings provide insights into the molecular and cellular mechanisms underlying BPA disturbance of goldfish reproduction.


Assuntos
Compostos Benzidrílicos/toxicidade , Carpa Dourada/crescimento & desenvolvimento , Gônadas , Fenóis/toxicidade , Reprodução/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Disruptores Endócrinos/toxicidade , Feminino , Células Germinativas/citologia , Carpa Dourada/metabolismo , Gônadas/efeitos dos fármacos , Células Intersticiais do Testículo/citologia , Masculino , Ovário/efeitos dos fármacos , Espermatogênese/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade
11.
Environ Sci Pollut Res Int ; 26(5): 5164-5175, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30604365

RESUMO

Polychlorinated diphenyl ethers (PCDEs) are a class of potential persistent organic contaminants, which have been widely detected in aquatic environment. In the present study, the effects of 3,4,4'-tri-CDE and its two possible metabolites (2-MeO-3',4,4'-tri-CDE and 2-HO-3',4,4'-tri-CDE) on oxidative stress biomarkers in liver of Carassius auratus were evaluated. The fish were treated with these three compounds at different doses (0.1, 1, and 10 µg/L) via semi-static water exposure. The liver samples were individually taken at 3, 7, and 21 days for analysis of oxidative stress indicators, including superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), reduced glutathione (GSH), and malondialdehyde (MDA). Compare to the control group, the hepatic antioxidant enzyme activity and GSH contents showed significant decreases (p < 0.05) at high-dose treatment (10 µg/L) and prolonged exposure time (21 days) in most of the toxicant-treated groups, indicating the occurrence of oxidative stress in fish liver. However, no consistent trend of the variations of antioxidant parameters was observed at low doses (0.1 and 1 µg/L). Meanwhile, the lipid peroxidation was significantly induced with extending exposure time and increasing dose. In addition, the toxicity order of three compounds was discussed using the integrated biomarker response (IBR) index. Notably, 2-HO-3',4,4'-tri-CDE was indicated to cause the most severe hepatic oxidative stress.


Assuntos
Antioxidantes/metabolismo , Carpa Dourada/metabolismo , Éteres Difenil Halogenados/toxicidade , Fígado/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores Ambientais/efeitos dos fármacos , Éteres Difenil Halogenados/análise , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Poluentes Químicos da Água/análise
12.
Artigo em Inglês | MEDLINE | ID: mdl-30528703

RESUMO

A 30-days feeding trail was conducted to determine the sensitivity of Carassius auratus to the toxicological effects of elevated dietary Selenomethionine (Se-Met). C. auratus averaging 23.56 ±â€¯1.82 g were exposed to four Se-Met concentrations (mg Se/kg): 0 (Se-Met0), 5 (Se-Met5), 10 (Se-Met10) and 20 (Se-Met20) to estimate the effects on tissue selenium (Se) accumulation, blood biochemical profiles, transcript expression and intestinal microbiota. Se accumulated in the kidney, liver and muscle in a dose-dependent manner and followed this order: kidney > liver > muscle, the highest accumulation were obtained in kidney of Se-Met20 diet after 30 days of feeding. Serum contents of alanine transaminase (ALT), aspartate transaminase (AST) and alkaline phosphatase (ALP) in fish exposed to Se-Met20 group was significantly highest among Se-Met exposure groups. Hydrogen peroxide (H2O2) concentrations in liver were affected by dietary Se-Met exposures. Liver contents of total antioxidant capacity (TAC), catalase (CAT), glutathione peroxidase (GPx) and malondialdehyde (MDA) in fish exposure to Se-Met5 group was significantly highest among Se-Met exposure groups. Growth hormone receptor (GHR), insulin-like growth factor 1 (IGF-1) and antioxidant enzyme related genes including glutathione peroxidase (GPx), catalase (CAT) and glutathione S-transferase (GST) expression in liver were down-regulated with the concentration of Se-Met exposure groups. The results of high-throughput sequencing showed that gut microbial communities and hierarchy cluster heatmap analysis were significantly affected by Se-Met exposure. The abundances of Cetobacterium and Vibrio increased while fish exposed to Se-Met20 group. The abundance of Ralstonia increased when the Se-Met exposure dose reached 10 mg Se kg-1. The results suggested that the exposure to elevated dietary Se-Met may result toxic effects in C. auratus.


Assuntos
Microbioma Gastrointestinal/efeitos dos fármacos , Carpa Dourada/sangue , Selenometionina/farmacocinética , Ração Animal , Animais , Antioxidantes/metabolismo , Dieta/veterinária , Regulação da Expressão Gênica/efeitos dos fármacos , Carpa Dourada/metabolismo , Carpa Dourada/microbiologia , Peróxido de Hidrogênio , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/metabolismo , Malondialdeído/metabolismo , Receptores da Somatotropina/genética , Receptores da Somatotropina/metabolismo , Selenometionina/farmacologia
13.
Environ Toxicol Pharmacol ; 62: 60-68, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29986279

RESUMO

Compared to single exposure, chemical mixtures might induce joint toxicity including additive, synergistic and antagonistic effects on both organisms and environment. Owing to the specific toxicity of oxidative stress and binding to proteins, lead (Pb) is generally recognized a non-essential and threatening heavy metal to animals and human. Paraquat (PQ) is a widely used herbicide in agriculture and can trigger oxidative stress as well as Pb. Little information was available about joint effects of the two chemicals on toxicological responses in organisms, especially in fish. In our present study, goldfish (Carassius auratus) were randomly exposed to single and combined experiments with different concentrations of Pb and PQ for 28 days. Activities of four enzyme biomarkers in liver, ethoxyresorufin-O-deethylase (EROD), 7-benzyloxy-4-trifluoromethyl-coumarin-O-debenzyloxylase (BFCOD), glutathione-S-transferase (GST) and UDP-glucuronosyltransferase (UGT) were evaluated in each experimental group on day 14 and 28. The results showed four enzyme levels were markedly reduced with the increase of concentrations in mixtures and prolonged exposure. The inhibitory EROD and BFCOD activities were not significantly changed in goldfish following PQ-treated groups with or without 0.5 mg/L Pb, which indicated PQ has more inhibitory toxicity on CYP450 enzymes than Pb in co-exposure groups. However, the reduced values of GST were observed only in the combinations containing high doses of Pb or PQ during experimental periods. Although the responses of UGT activity were similar to GST on 14th day, all combinations of Pb and PQ generated stronger inhibitions on UGT activities compared to individual Pb and PQ-treated group. These results suggested that combined exposure of Pb and PQ have more inhibitory toxicity on phase I enzymes than phase II enzymes.


Assuntos
Carpa Dourada/metabolismo , Herbicidas/toxicidade , Chumbo/toxicidade , Fígado/efeitos dos fármacos , Paraquat/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Citocromo P-450 CYP1A1/metabolismo , Sinergismo Farmacológico , Glucuronosiltransferase/metabolismo , Glutationa Transferase/metabolismo , Inativação Metabólica/efeitos dos fármacos , Fígado/enzimologia
14.
PLoS One ; 13(5): e0197817, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29791497

RESUMO

Xenin, a highly conserved 25 amino acid peptide cleaved from the N-terminus of the coatomer protein alpha (COPA), is emerging as a food intake regulator in mammals and birds. To date, no research has been conducted on xenin biology in fish. This study aims to identify the copa mRNA encoding xenin in goldfish (Carassius auratus) as a model, to elucidate its regulation by feeding, and to describe the role of xenin on appetite. First, a partial sequence of copa cDNA, a region encoding xenin, was identified from goldfish brain. This sequence is highly conserved among both vertebrates and invertebrates. RT-qPCR revealed that copa mRNAs are widely distributed in goldfish tissues, with the highest levels detected in the brain, gill, pituitary and J-loop. Immunohistochemistry confirmed also the presence of COPA peptide in the hypothalamus and enteroendocrine cells on the J-loop mucosa. In line with its anorexigenic effects, we found important periprandial fluctuations in copa mRNA expression in the hypothalamus, which were mainly characterized by a gradually decrease in copa mRNA levels as the feeding time was approached, and a gradual increase after feeding. Additionally, fasting differently modulated the expression of copa mRNA in a tissue-dependent manner. Peripheral and central injections of xenin reduce food intake in goldfish. This research provides the first report of xenin in fish, and shows that this peptide is a novel anorexigen in goldfish.


Assuntos
Carpa Dourada/metabolismo , Neurotensina/metabolismo , Sequência de Aminoácidos , Animais , Encéfalo/metabolismo , Ingestão de Alimentos , Células Enteroendócrinas/metabolismo , Feminino , Hipotálamo/metabolismo , Fígado/metabolismo , Masculino , Neurotensina/classificação , Neurotensina/genética , Filogenia , RNA Mensageiro/metabolismo
15.
Chemosphere ; 205: 8-14, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29679789

RESUMO

Fluoxetion (FLU) is an antidepressant pharmaceutical most commonly detected in the aquatic environment. The present study aims to elucidate the tissue accumulation and effects of FLU using two different fish models. First, the multiple effects and the FLU levels in fish, were examined in zebrafish (Danio rerio) embryos exposed to FLU concentrations (0, 0.1, 1, 10, 100, 1000 µg/L) from 4 h post-fertilization (hpf) until 120 hpf. Exposure to FLU accelerated heart rates, postponed hatching time, and increased swimming speed of fish. A dynamic response of acetylcholinesterase (AChE) activity was also displayed in the fish. Second, a 30-day exposure experiment using red crucian carp (Carassius auratus) was performed, and it found that the concentration of FLU in fish organs increased with increasing water concentrations, but the highest FLU bioconcentration was present in the lowest FLU exposure group (0.1 µg/L). Finally, 6 days of exposure to 0.1 µg/L of FLU followed by a 6-day clearance experiment was performed with both adult zebrafish and red crucian carp. The FLU levels in different fish organs increased as exposure time increased, but they sharply declined following the 6-day clearance. Correspondingly, the changes in brain AChE activity and in antioxidant parameters in the liver were consistent with the FLU levels in the fish organs. Our study provides fundamental data on the tissue accumulation and concentration-dependent effects in fish exposed to fluoxetine.


Assuntos
Exposição Ambiental/análise , Fluoxetina/farmacologia , Carpa Dourada/metabolismo , Inibidores de Captação de Serotonina/farmacologia , Peixe-Zebra/metabolismo , Acetilcolinesterase/metabolismo , Animais , Carpa Dourada/crescimento & desenvolvimento , Fatores de Tempo , Peixe-Zebra/crescimento & desenvolvimento
16.
Gen Comp Endocrinol ; 262: 99-105, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29574148

RESUMO

We examined the effects of α-melanocyte-stimulating hormone (α-MSH) on bone metabolism using regenerating goldfish scales. Normally developed scales on the bodies of goldfish were removed to allow the regeneration of scales under anesthesia. Thereafter, the influence of α-MSH on the regeneration of goldfish scales was investigated in vivo. In brief, α-MSH was injected at a low dose (0.1 µg/g body weight) or a high dose (1 µg/g body weight) into goldfish every other day. Ten days after removing the scales, we collected regenerating scales and analyzed osteoblastic and osteoclastic activities as respective marker enzyme (alkaline phosphatase for osteoblasts, tartrate-resistant acid phosphatase for osteoclasts) activity in the regenerating scales as well as plasma calcium levels. At both doses, osteoblastic and osteoclastic activities in the regenerating scales increased significantly. Plasma calcium concentrations in the α-MSH-treated group (high doses) were significantly higher than those in the control group. Next, in vitro experiments were performed to confirm the results of in vivo experiments. In the cultured regenerating scales, osteoblastic and osteoclastic activities significantly increased with α-MSH (10-7 and 10-6 M) treatment. In addition, real-time PCR analysis indicated that osteoclastogenesis in α-MSH-treated scales was induced by the receptor activator of the NF-κB/receptor activator of the NF-κB ligand/osteoprotegerin pathway. Furthermore, we found that α-MSH receptors (melanocortin receptors 4 and 5) were detected in the regenerating scales. Thus, in teleosts, we are the first to demonstrate that α-MSH functions in bone metabolism and promotes bone resorption via melatonin receptors 4 and/or 5.


Assuntos
Reabsorção Óssea/patologia , Carpa Dourada/metabolismo , Osteoblastos/metabolismo , Osteoclastos/metabolismo , alfa-MSH/farmacologia , Fosfatase Alcalina/metabolismo , Escamas de Animais/metabolismo , Animais , Reabsorção Óssea/genética , Cálcio/sangue , Cálcio/metabolismo , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Carpa Dourada/sangue , Osteoblastos/efeitos dos fármacos , Osteoclastos/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Regeneração/efeitos dos fármacos
17.
Biochem Biophys Res Commun ; 498(3): 680-685, 2018 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-29530529

RESUMO

Cell migration involves the precise coordination between extension at the front of the cell and retraction at the rear. This coordination is particularly evident in fast moving cells such as fish keratocytes, where it leads to highly stable gliding motion, propelled at the front by broad, 0.1-0-2 µm thick lamellipodia. Transient uncoupling between extension and retraction can occur if the rear is temporarily stuck, which might eventually lead to cell shape instabilities. We have frequently observed in fish keratocytes the presence of lamellipodial radial wrinkles, detected by confocal, scanning electron and side-view microscopy as folds in the lamellipodium up to 2 µm in height. Using a linear finite elements analysis, we simulated the displacement of cells either with perfect coordination between extension and retraction or with the rear transiently stuck while the front continues extending, and we observed that in this last condition compression stresses arise in the lamellipodium which predict the formation of the observed pattern of lamellipodial wrinkles. In support of the numerical modeling findings, we observed that the transient halting of retraction at the rear using micromanipulation induced the formation of lamellipodial wrinkles in previously flat lamellipodia. The obtained results suggest that the conspicuous lamellipodial wrinkles observed in migrating fish keratocytes are the product of transient imbalances between front and rear displacements, and are therefore useful markers of the short scale dynamics of extension and retraction coordination during cell migration.


Assuntos
Movimento Celular , Queratinócitos/citologia , Pseudópodes/ultraestrutura , Animais , Células Cultivadas , Simulação por Computador , Análise de Elementos Finitos , Carpa Dourada/metabolismo , Queratinócitos/metabolismo , Queratinócitos/ultraestrutura , Microscopia Confocal , Modelos Biológicos , Pseudópodes/metabolismo
18.
Fish Physiol Biochem ; 44(3): 841-852, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29464406

RESUMO

Copper is an essential element, but at high concentrations, it is toxic for living organisms. The present study investigated the responses of goldfish, Carassius auratus, to 96 h exposure to 30, 300, or 700 µg L-1 of copper II chloride (Cu2+). The content of protein carbonyls was higher in kidney (by 158%) after exposure to 700 mg L-1 copper, whereas in gills, liver, and brain, we observed lower content of protein carbonyls after exposure to copper compared with control values. Exposure to copper resulted in increased levels of lipid peroxides in gills (76%) and liver (95-110%) after exposure to 300 and 700 µg L-1 Cu2+. Low molecular mass thiols were depleted by 23-40% in liver and by 29-67% in kidney in response to copper treatment and can be used as biomarkers toxicity of copper. The activities of primary antioxidant enzymes, superoxide dismutase and catalase, were increased in liver as a result of Cu2+ exposure, whereas in kidney catalase activity was decreased. The activities of glutathione-related enzymes, glutathione peroxidase, glutathione-S-transferase, and glutathione reductase were decreased as a result of copper exposure, but glutathione reductase activity increased by 25-40% in liver. Taken together, these data show that exposure of fish to Cu2+ ions results in the development of low/high intensity oxidative stress reflected in enhanced activities of antioxidant and associated enzymes in different goldfish tissues.


Assuntos
Encéfalo/efeitos dos fármacos , Cobre/toxicidade , Brânquias/efeitos dos fármacos , Carpa Dourada/metabolismo , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Animais , Encéfalo/metabolismo , Catalase/metabolismo , Brânquias/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Glutationa Transferase/metabolismo , Rim/metabolismo , Fígado/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Carbonilação Proteica/efeitos dos fármacos
19.
J Vet Pharmacol Ther ; 41(4): 599-604, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29465160

RESUMO

The pharmacokinetics of orbifloxacin was studied after a single dose (7.5 mg/kg) of intravenous or intramuscular administration to crucian carp (Carassius auratus) reared in freshwater at 25°C. Plasma samples were collected from six fish per sampling point. Orbifloxacin concentrations were determined by high-performance liquid chromatography with a 0.02 µg/ml limit of detection, then were subjected to noncompartmental analysis. After intravenous injection, initial concentration of 5.83 µg/ml, apparent elimination rate constant (λz ) of 0.039 hr-1 , apparent elimination half-life (T1/2λz ) of 17.90 hr, systemic total body clearance (Cl) of 75.47 ml hr-1  kg-1 , volume of distribution (Vz) of 1,948.76 ml/kg, and volume of distribution at steady-state (Vss) of 1,863.97 ml/kg were determined, respectively. While after intramuscular administration, the λz , T1/2λz , mean absorption time (MAT), absorption half-life (T1/2ka ), and bioavailability were determined as 0.027 hr-1 , 25.69, 10.26, 7.11 hr, and 96.46%, respectively, while the peak concentration was observed as 3.11 ± 0.06 µg/ml at 2.0 hr. It was shown that orbifloxacin was completely but relatively slowly absorbed, extensively distributed, and slowly eliminated in crucian carp, and an orbifloxacin dosage of 10 mg/kg administered intravenously or intramuscularly would be expected to successfully treat crucian carp infected by strains with MIC values ≤0.5 µg/ml.


Assuntos
Antibacterianos/farmacocinética , Ciprofloxacino/análogos & derivados , Carpa Dourada/metabolismo , Animais , Antibacterianos/administração & dosagem , Antibacterianos/sangue , Cromatografia Líquida de Alta Pressão/veterinária , Ciprofloxacino/administração & dosagem , Ciprofloxacino/sangue , Ciprofloxacino/farmacocinética , Carpa Dourada/sangue , Meia-Vida , Injeções Intramusculares/veterinária , Injeções Intravenosas/veterinária
20.
Ecotoxicol Environ Saf ; 151: 161-169, 2018 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-29353166

RESUMO

As the producer of reactive oxygen species (ROS), both lead (Pb) and paraquat (PQ) can generate serious oxidative stress in target organs which result in irreversible toxic effects on organisms. They can disturb the normal catalytic activities of many enzymes by means of different toxicity mechanism. The changed responses of enzymes are frequently used as the biomarkers for indicating the relationship between toxicological effects and exposure levels. In this work, goldfish was exposed to a series of test groups containing lead and paraquat in the range of 0.05-10mg/L, respectively. Four hepatic enzyme activities, including 7-ethoxyresorufinO-deethylase (EROD), 7-benzyloxy-4-trifluoromethyl-coumarin-O-debenzyloxylase (BFCOD), glutathione S-transferase (GST) and UDP-glucuronosyltransferase (UGT) were determined after 1, 7, 14, 28 days exposure. The results showed that the activities of EROD and BFCOD in fish were significantly inhibited in response to paraquat at all exposure levels during the whole experiment. Similarly, the inhibitory effects of lead exposure on BFCOD activity were found in our study, while different responses of lead on EROD were observed. There were no significant differences on EROD activity under lower concentrations of lead (less than 0.1mg/L) before 14 days until an obvious increase was occurred for the 0.5mg/L lead treatment group at day 14. Furthermore, lead showed stronger inhibition on GST activity than paraquat when the concentrations of the two toxicants were more than 0.5mg/L. However, the similar dose and time-dependent manners of UGT activity were found under lead and paraquat exposure. Our results indicated that higher exposure levels and longer accumulations caused inhibitory effects on the four enzymes regardless of lead or paraquat stress. In addition, the responses of phase I enzymes were more sensitive than that of phase II enzymes and they may be served as the acceptable biomarkers for evaluating the toxicity effects of both lead and paraquat.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Carpa Dourada/metabolismo , Chumbo/toxicidade , Fígado/efeitos dos fármacos , Paraquat/toxicidade , Transferases/metabolismo , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Glucuronosiltransferase/metabolismo , Glutationa Transferase/metabolismo , Chumbo/metabolismo , Fígado/enzimologia , Estresse Oxidativo
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