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1.
Environ Monit Assess ; 191(11): 700, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31667668

RESUMO

The distribution of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) in the muscle, liver, spleen and kidney tissue of two fish species was studied using an optimised diatomaceous earth assisted modified QuEChERS extraction method. Five-year-old free-ranging male African sharptooth catfish (Clarias gariepinus) and 5-year-old male common carp (Cyprinus carpio) sampled from the Hartbeespoort Dam in South Africa were used for method development. Acetonitrile extraction produced more precise recoveries than hexane extraction. Fluorene and naphthalene were the most abundant PAHs detected in the majority of fish tissues analysed. PAH bioaccumulation in 5-year-old carp and 5-year-old catfish was in the order muscle > kidney > liver > spleen and liver > muscle > kidney > spleen, respectively. PCBs were mostly detected in carp spleen and kidney. Two-year-old carp were analysed to determine PCB and PAH bioaccumulation trends. The differences in ∑16PAH concentrations between the four organs tested were all statistically insignificant for the 3 fish tested (p > 0.05). All other organs with the exception of 5-year-old carp spleen and 5-year-old carp kidney recorded total 31 PCB concentrations (∑31PCB) < 25 ng g-1. Only 5-year-old carp spleen (∑31PCB of 592 ng g-1) and 5-year-old carp kidney (∑31PCB of 561 ng g-1) had significant differences (p < 0.05) from the spleen and kidney in 5-year-old catfish and 2-year-old carp. Whilst the carp and catfish sampled can be considered low PCB risk foods, 5-year-old carp muscle can be considered to be a high PAH risk food, with a benzo(a)pyrene concentration of 7 µg g-1, based on the EU Commission Regulation 2005/208/EC pertaining to the maximum permissible benzo(a)pyrene level in fresh fish muscle.


Assuntos
Carpas/metabolismo , Peixes-Gato/metabolismo , Monitoramento Ambiental , Bifenilos Policlorados/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Bioacumulação , Peixes-Gato/fisiologia , Fígado/metabolismo , Masculino , Músculos/química , Bifenilos Policlorados/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , África do Sul
2.
An Acad Bras Cienc ; 91(4): e20190075, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31778460

RESUMO

The purpose of this study was to assess the effect of different carbohydrate and lipid (CHO/L) ratios on the performance and energy metabolism of hybrid catfish (♂Pseudoplatystoma corruscans × â™€ Pseudoplatystoma fasciatum). One hundred and sixty-eight fish (104.9±16.5 g BW) were distributed into 24 100-L tanks. The experiment was performed using a randomised block design with four CHO/L ratios (0.45, 1.00, 1.66 and 2.85) and six replications. Growth performance, protein content, glucose and triglycerides in plasma, muscle and liver, and the hepatic activity of the malic and glucose-6-phosphate dehydrogenase (G6PD) enzymes were measured after 60 feeding days. No significant differences were observed in growth performance, protein and triglycerides of plasma and muscle, hepatic protein or malic enzyme activity. CHO/L: 2.85 provided the highest plasma and liver glucose, while CHO/L: 0.45 showed high liver triglycerides. A linear effect was found for the hepatic activity of G6PD and dietary starch levels (R2=0.93). The hepatic activity of G6PD was greater in CHO/L=2.85 than for CHO/L: 0.45. In conclusion, the limit of dietary starch inclusion and lipids were 15% and 9.00%, respectively (CHO/L: 1.66), and this level did not affect the energy metabolism of the juvenile hybrid catfish.


Assuntos
Ração Animal , Peixes-Gato/metabolismo , Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Lipídeos/administração & dosagem , Animais , Peixes-Gato/sangue , Peixes-Gato/crescimento & desenvolvimento , Carboidratos da Dieta/sangue , Gorduras na Dieta/sangue , Lipídeos/sangue
3.
Aquat Toxicol ; 217: 105329, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31648108

RESUMO

Little is known about the effects of oxyfluorfen, a diphenyl ether herbicide, exposure on the African catfish (Clarias gariepinus) health. Consequently, the existing investigation was designed to highlight the impacts of oxyfluorfen exposure on C. gariepinus hematological indices, liver and kidney functions, reproductive hormones, and oxidative status. Furthermore, a consequent 10-day depuration period was adopted to evaluate the recovery of the disturbed indicators to normal values. In the first experiment, the 96-h lethal concentration 50 (LC50) of oxyfluorfen for C. gariepinus was determined using probit analysis. Next, in a second experiment, 180 healthy fish (average initial body weight: 164.23 ±â€¯0.24) were randomly assigned to 4 experimental groups exposed to 0, 1/10, 1/8, or 1/5 96-h LC50 of oxyfluorfen. The hematological profile, hepatic enzymes, kidney damage byproducts, reproductive hormones, oxidative stress, and lipid peroxidation indicators together with acetylcholinesterase (AChE) content were assessed. A histopathological examination of the hepatic, renal, brain, and testicular tissues was accomplished. Moreover, the expression of the oxidative stress-related gene was carried out. The results showed that 96-h LC50 of oxyfluorfen for C. gariepinus was 11.698 mg/L. Exposure to sublethal levels of oxyfluorfen induced macrocytic hypochromic anemia, leukopenia, lymphopenia, monocytopenia, and eosinopenia. Also, a concentration-dependent increase in alanine transaminase, alkaline phosphatase, aspartate transaminase, urea, creatinine, catalase, and malondialdehyde was detected following oxyfluorfen exposure together with upregulation of catalase gene. But, significant concentration-dependent reductions in AChE, glutathione transferase, reduced to oxidized glutathione ratio, estradiol, and testosterone activities were recorded. These biochemical alterations were accompanied by pathological perturbations in hepatic, renal, brain, and testicular tissues. Following 10 days of recovery, only the hematological impairments were abolished. Conclusively, the herbicides oxyfluorfen could induce multiple negative impacts on C. gariepinus with oxidative stress as a probable underlying mechanism. Additionally, a recovery period of 10 days was not enough to restore these impairments.


Assuntos
Antioxidantes/metabolismo , Peixes-Gato/metabolismo , Exposição Ambiental , Éteres Difenil Halogenados/toxicidade , Hormônios/metabolismo , Rim/patologia , Fígado/patologia , Acetilcolinesterase/metabolismo , Animais , Catalase/genética , Catalase/metabolismo , Peixes-Gato/sangue , Eritrócitos/efeitos dos fármacos , Eritrócitos/patologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Herbicidas/metabolismo , Concentração Inibidora 50 , Rim/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Reprodução/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade
4.
Genes (Basel) ; 10(10)2019 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-31557940

RESUMO

The autophagy-lysosome pathway, which involves many crucial genes and proteins, plays crucial roles in the maintenance of intracellular homeostasis by the degradation of damaged components. At present, some of these genes and proteins have been identified but their specific functions are largely unknown. This study was performed to clone and characterize the full-length cDNA sequences of nine key autolysosome-related genes (vps11, vps16, vps18, vps33b, vps41, lamp1, mcoln1, ctsd1 and tfeb) from yellow catfish Pelteobagrus fulvidraco. The expression of these genes and the transcriptional responses to a high-fat diet and fatty acids (FAs) (palmitic acid (PA) and oleic acid (OA)) were investigated. The mRNAs of these genes could be detected in heart, liver, muscle, spleen, brain, mesenteric adipose tissue, intestine, kidney and ovary, but varied with the tissues. In the liver, the mRNA levels of the nine autolysosome-related genes were lower in fish fed a high-fat diet than those fed the control, indicating that a high-fat diet inhibited formation of autolysosomes. Palmitic acid (a saturated FA) significantly inhibited the formation of autolysosomes at 12 h, 24 h and 48 h incubation. In contrast, oleic acid (an unsaturated FA) significantly induced the formation of autolysosomes at 12 h, but inhibited them at 24 h. At 48 h, the effects of OA incubation on autolysosomes were OA concentration-dependent in primary hepatocytes of P. fulvidraco. The results of flow cytometry and laser confocal observations confirmed these results. PA and OA incubation also increased intracellular non-esterified fatty acid (NEFA) concentration at 12 h, 24 h and 48 h, and influenced mRNA levels of fatty acid binding protein (fabp) and fatty acid transport protein 4 (fatp4) which facilitate FA transport in primary hepatocytes of P. fulvidraco. The present study demonstrated the molecular characterization of the nine autolysosome-related genes and their transcriptional responses to fat and FAs in fish, which provides the basis for further exploring their regulatory mechanism in vertebrates.


Assuntos
Autofagossomos/metabolismo , Peixes-Gato/metabolismo , Gorduras na Dieta/farmacologia , Ácidos Graxos/farmacologia , Fígado/metabolismo , Lisossomos/metabolismo , Animais , Gorduras na Dieta/metabolismo , Proteínas de Ligação a Ácido Graxo/genética , Proteínas de Ligação a Ácido Graxo/metabolismo , Ácidos Graxos/metabolismo , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Fígado/efeitos dos fármacos , Glicoproteínas de Membrana Associadas ao Lisossomo/genética , Glicoproteínas de Membrana Associadas ao Lisossomo/metabolismo , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/metabolismo
5.
Artigo em Inglês | MEDLINE | ID: mdl-31493583

RESUMO

The four experimental groups were carried out to test the response of yellow catfish to EE2 and DEHP: control group was exposed to DMSO; EE2 group was exposed to 1.0 µg/L EE2; DEHP group was exposed to 1.0 mg/L DEHP; mix group was exposed to 1.0 µg/L EE2 and 1.0 mg/L DEHP. The experiment continued for 56 days. Fish survival rate was not different among experimental groups. Fish in DEHP and mix groups had the highest weight gain, and lowest value appeared in control group. The highest hepatosomatic index was found in DEHP and mix groups. Serum alanine transaminase of fish in control group was lower than other groups, but the alkaline phosphatase value was the highest. Serum total anti-oxidation capacity, superoxide dismutase and catalase activities of fish in control group were higher than other groups, but malondialdehyde content is opposite. Respiratory burst and phagocytic indices of fish in EE2 group were the lowest. After 96 h of ammonia stress, the survival rate of fish in mix group was significantly lower than control group. This study indicates that EE2 and DEHP exposure can lead to gain weight of yellow catfish, which is related to liver damage and fat accumulation; EE2 and DEHP exerts its toxic effects by inducing ROS generation, leading to lipid peroxidation and immunosuppression.


Assuntos
Antioxidantes/metabolismo , Peixes-Gato , Dietilexilftalato/toxicidade , Etinilestradiol/toxicidade , Fígado/metabolismo , Poluentes Químicos da Água/toxicidade , Animais , Peixes-Gato/imunologia , Peixes-Gato/metabolismo , Peroxidação de Lipídeos , Estresse Oxidativo
6.
Artigo em Inglês | MEDLINE | ID: mdl-31394254

RESUMO

The present study aimed to evaluate the protective role of Selenium (Se) (0.1 ppm) on the male reproductive system of the catfish Clarias gariepinus exposed to sublethal doses of Mercury (Hg) (0.04 and 0.12 ppm) for 30 days. Indicators of seminal and gonadal hormone disruption (testosterone, estradiol and 11 keto testosterone), antioxidants (total antioxidant capacity (TAO), superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx)), oxidative stress biomarkers (lipid peroxidation (LPO), percentage of DNA fragmentation, carbonylated proteins (CP) and nitric oxide (NO)) and histopathological alterations in testicles of Clarias gariepinus were determined. The exposure to Hg resulted in a high accumulation of residues of this metal in testicular tissues. The results showed a significant decrease in sperm count, activity and motility and in all gonadal hormones in Hg exposed groups. Hg exposure also induced a decline in TAO, SOD, CAT and GPx, whereas LPO, DNA fragmentation, CP and NO significantly increased in testicles of C. gariepinus respect to the control group. Although exposure to Se did not reduce the degree of mercury bioconcentration in the testicles, the sperm quality parameters were recovered. Moreover, TAO levels and GPx activity significantly increased after fish exposure to Se, whereas CP levels decreased. LPO, NO, CAT and SOD were also partially normalized when compared with the groups exposed to only Hg. In conclusion, the results showed that Hg, even in the small doses is capable to induce reproductive toxicity in the male catfish. Se exposure partially restored the values of biochemical parameters and sperm quality in Hg-treated fish suggesting protective effects against Hg reproductive toxicity.


Assuntos
Peixes-Gato/metabolismo , Mercúrio/toxicidade , Selênio/farmacologia , Espermatozoides , Testículo , Animais , Antioxidantes/metabolismo , Biomarcadores/metabolismo , Hormônios Gonadais/metabolismo , Masculino , Intoxicação por Mercúrio/tratamento farmacológico , Espermatozoides/efeitos dos fármacos , Espermatozoides/patologia , Testículo/efeitos dos fármacos , Testículo/patologia , Poluentes Químicos da Água/toxicidade
7.
Artigo em Inglês | MEDLINE | ID: mdl-31394255

RESUMO

In the present study, we investigated plasma biochemical and steroid hormone responses, together with gonado-histopathological alterations in Clarias gariepinus exposed to sublethal concentrations of two synthetic pyrethroids (cypermethrin and deltamethrin). Fish were exposed to environmentally-relevant concentrations of cypermethrin at 0 (ethanol solvent control), 0.07, 0.014, 0.028, 0.056) and deltamethrin at 0.22, 0.44, 0.88 and 1.76 µg/L, for 7, 14, 21 and 28 days. Plasma enzyme (aspartate transaminase: AST, alanine transaminase: ALT and alkaline phosphatase: ALP) and steroid hormones (estradiol-17ß: E2, testosterone: T) levels were analyzed. Gonado-histopathological evaluation shows the presence of ovo-testis (intersex), oocytes atresia, cytoplasmic degeneration and clumping of vitellogenic oocytes in females, while male fish displayed enlargement and degeneration of testicular seminiferous tubules after 28 days exposure to cypermethrin and deltamethrin. Plasma biochemical analysis in pesticides exposed fish revealed that AST, ALT and ALP were significantly increased in a concentration-dependent manner. In addition, we observed respective and apparent concentration- and time-dependent increase and decrease of plasma E2 and T levels, compared to control. Interestingly, the significant increase in E2 levels paralleled gonadal ovo-testis (intersex) condition in exposed fish, indicating endocrine disruptive effects of cypermethrin and deltamethrin that favor the estrogenic pathway, in addition to overt negative consequences on reproductive, biochemical and physiological health of the exposed fish.


Assuntos
Peixes-Gato/metabolismo , Disruptores Endócrinos/sangue , Nitrilos/toxicidade , Ovário/metabolismo , Piretrinas/toxicidade , Testículo/metabolismo , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Animais , Aspartato Aminotransferases/sangue , Estradiol/sangue , Feminino , Masculino , Ovário/patologia , Reprodução , Testículo/patologia , Testosterona/sangue , Poluentes Químicos da Água/toxicidade
8.
Environ Toxicol Pharmacol ; 71: 103222, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31426013

RESUMO

The Roodeplaat Dam and its three inflowing rivers are highly impacted by surrounding anthropogenic activities. The system is hyper-eutrophic and characterized by seasonal algal blooms and previous studies have reported levels of the hepatotoxin microcystin in the water of the impoundment. Limited information is available on the microcystin concentrations in the inflowing rivers and no information is available on the bioaccumulated levels and potential health effects in fish inhabiting these rivers. The aim of this study was to do a histopathological assessment and to determine the concentrations of bioaccumulated microcystins in the livers of two indicator fish species Clarias gariepinus and Oreochromis mossambicus. The results showed that the two species bioaccumulate microcystins at different concentrations and that their hepatic health response varied. The liver index was significantly higher for C. gariepinus compared to O. mossambicus. No significant positive correlation was found between the bioaccumulated microcystin levels and the liver histology index. It is recommended that this pilot study be followed by a controlled exposure study to confirm a possible cause and effect relationship between microcystin exposure and the specific liver alterations identified.


Assuntos
Peixes-Gato/metabolismo , Fígado/efeitos dos fármacos , Fígado/patologia , Microcistinas/toxicidade , Rios/química , Tilápia/metabolismo , Poluentes Químicos da Água/toxicidade , Animais , Bioacumulação , Monitoramento Ambiental , Eutrofização , Fígado/metabolismo , Microcistinas/metabolismo , Projetos Piloto , África do Sul , Especificidade da Espécie , Poluentes Químicos da Água/metabolismo
9.
Environ Sci Pollut Res Int ; 26(26): 27470-27481, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31332682

RESUMO

Unanticipated increase in the use of silver (Ag) and copper oxide (CuO) nanoparticles (NPs) due to their antimicrobial properties is eliciting environmental health concern because of their coexistence in the aquatic environment. Therefore, we investigated the genetic and systemic toxicity of the individual NPs and their mixture (1:1) using the piscine micronucleus (MN) assay, haematological, histopathological (skin, gills and liver) and hepatic oxidative stress analyses [malondialdehyde (MDA), reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT)] in the African mud catfish, Clarias gariepinus. The fish were exposed to sublethal concentrations (6.25-100.00 mg/L) of each NP and their mixture for 28 days. Both NPs and their mixture induced significant (p < 0.05) increase in MN frequency and other nuclear abnormalities. There was significant decrease in haemoglobin concentration, red and white blood cell counts. Histopathological lesions observed include epidermal skin cells and gill lamellae hyperplasia and necrosis of hepatocytes. The levels of MDA, GSH and activities of SOD and CAT were impacted in C. gariepinus liver following the exposure to the NPs and their mixture. Interaction factor analysis of data indicates antagonistic genotoxicity and oxidative damage of the NPs mixture. These results suggest cytogenotoxic effects of Ag NPs, CuO NPs and their mixture via oxidative stress in Clarias gariepinus.


Assuntos
Peixes-Gato , Cobre/toxicidade , Nanopartículas Metálicas/toxicidade , Prata/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Catalase/metabolismo , Peixes-Gato/metabolismo , Ecotoxicologia , Proteínas de Peixes/metabolismo , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Brânquias/patologia , Glutationa/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Malondialdeído/farmacologia , Testes para Micronúcleos , Estresse Oxidativo/efeitos dos fármacos , Prata/química , Pele/efeitos dos fármacos , Pele/metabolismo , Pele/patologia , Superóxido Dismutase/metabolismo
10.
Environ Monit Assess ; 191(8): 493, 2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31300901

RESUMO

Clarias gariepinus (African catfish) and Oreochromis niloticus (Tilapia fish) from the right North bank of the Senegal River in Mauritania (Rosso, Boghé, and Kaédi) were sampled during 1-year monitoring and tested for lead (Pb), cadmium (Cd), and mercury (Hg) levels. Fishing from the Senegal River is an essential source of food for the local population and these two species are the most common. Muscle presents higher Hg concentrations than liver and gills for both species. Gill Hg concentrations from Kaédi are higher than Boghé and Rosso for both species. The Cd levels measured in gills were low in the different locations and revealed high variation throughout the 1-year study. No significant differences were observed between concentrations of Cd in Clarias gariepinus and Oreochromis niloticus parts. Statistical treatment did not show a considerable variation of Pb concentration between the different parts, revealing lower levels in gills from Boghé than the ones from Kaédi and Rosso. The associated human health risk was calculated from the concentration levels using the target hazard quotient (THQ) approach. Even though all the THQ values and the hazard index were lower than 1 for the determined trace metals when the exposure frequency was not greater than three times a week, eating frequency in the studied locations sometimes is greater than five, thus posing a health risk, especially at Kaédi and Boghé.


Assuntos
Peixes-Gato/metabolismo , Ciclídeos/metabolismo , Monitoramento Ambiental/métodos , Metais Pesados/análise , Rios/química , Poluentes Químicos da Água/análise , Animais , Brânquias/química , Humanos , Fígado/química , Mauritânia , Músculos/química , Medição de Risco , Alimentos Marinhos/análise
11.
Aquat Toxicol ; 214: 105233, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31301545

RESUMO

The water bodies are greatly influenced by heavy metal contamination and global increasing temperature. Arsenic (As) is one of the most dangerous widespread pollutants that pose health threats to human, animals and fishes. Considering the above, the study has been carried out to delineate 96 h median lethal concentration of arsenic alone and in combination with high temperature (As-T, 34 °C) by conducting static non-renewable bio-assay acute toxicity in Pangasianodon hypophthalmus (average weight 6.25 ±â€¯0.69 g, length 5.32 cm). Effect of definitive doses such as 25, 26, 27, 28, 29 and 30 mg/L of As alone and in combination with high temperature (As-T) were evaluated on stress biomarkers and cellular metabolism of P. hypophthalmus. The lethal concentration (96 h LC50) of As alone and in combination with high temperature was found to be 28.16 mg/L and 26.88 mg/L, respectively. The stress biomarkers in terms of catalase, superoxide dismutase (SOD) and glutathione-s-transferase (GST) in liver, gill, brain and kidney, blood glucose and NBT were remarkable higher (p < 0.01) in comparison to unexposed group (control group). Brain neurotransmitter enzyme, AChE, immunological status (blood glucose and NBT) and cellular metabolic enzymes (lactate dehydrogenase LDH, malate dehydrogenase MDH, aspartate aminotransferase AST, and alanine aminotransferase ALT, glucose-6-phosphate dehydrogenase G6PDH and ATPase) were noticeably (p < 0.01) altered by As and As-T exposure. The histopathological study exhibited devastating changes with exposure to As and As-T such as bile stagnation, hepatocyte with irregular nucleus, eosinophilic granules in the cytoplasm, necrosis, and nuclear hypertrophy in liver and curling of secondary lamellae, hypertrophy of lamellar epithelium, blood congestion, incomplete fusion of secondary lamellae, complete fusion of several lamellae and aneurysm in gill. Overall results clearly indicate that acute exposure of As and high temperature led to pronounced deleterious alterations on stress biomarkers and cellular and metabolic activities of P. hypophthalmus.


Assuntos
Arsênico/toxicidade , Biomarcadores/metabolismo , Peixes-Gato/imunologia , Peixes-Gato/metabolismo , Temperatura Alta , Estresse Oxidativo , Estresse Fisiológico/efeitos dos fármacos , Testes de Toxicidade Aguda , Acetilcolinesterase/metabolismo , Animais , Antioxidantes/metabolismo , Glicemia/metabolismo , Catalase/metabolismo , Brânquias/metabolismo , Glutationa Transferase/metabolismo , Glicólise/efeitos dos fármacos , Dose Letal Mediana , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Metais Pesados/metabolismo , Neurotransmissores/metabolismo , Superóxido Dismutase/metabolismo , Poluentes Químicos da Água/toxicidade
12.
Int J Biol Macromol ; 138: 773-780, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31351952

RESUMO

Catfish glycoprotein (CFG) was extracted from the cutaneous mucus of Egyptian catfish by ammonium sulphate precipitation and purified on gel filtration column (sephadex G-50). After purification, CFG produced one band on SDS-PAGE (22 kDa). Urea-PAGE and the pH-solubility of CFG indicated its positive charge (IEP 8). CFG contained 12 saccharides. FTIR spectrum shows 3 groups of bands at 1800-2900, 1100-1700 and 700-1100 cm-1. CFG exhibited antibacterial activity against 9 pathogenic bacteria with low MIC (50 µg/mL), where two Gram+ bacteria, i.e.; Streptococcus pyogenes (St. pyogenes) and Listeria ivanovii (L. ivanovii) were the most sensitive. The growth curves of the bacteria subjected to 1 MIC of CFG during 30 h showed general growth inhibition, particularly in case of Gram- bacteria such as E. coli. TEM images showed evidently reduced relative content of the intact cells and clear incurred cellular malformations. Combining CFG with specific antibiotic at equal ratios induced synergistic antibacterial actions, amounting to 40% of the mathematical sum of the combination. Substituting the antibiotic chloramphenicol with gradual increasing ratios of CFG of its starting concentration (30 µg/mL), produced proportionally bigger antibacterial actions against St. pyogenes growth and increasing synergistic effect up to 37% at 80% of CFG substitution.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Peixes-Gato , Glicoproteínas/química , Glicoproteínas/farmacologia , Muco/química , Animais , Antibacterianos/isolamento & purificação , Peixes-Gato/metabolismo , Relação Dose-Resposta a Droga , Glicoproteínas/isolamento & purificação , Testes de Sensibilidade Microbiana , Análise Espectral , Relação Estrutura-Atividade
13.
J Food Sci ; 84(7): 1957-1965, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31242536

RESUMO

A total of 600 freshly caught fish samples (200 each of Nile tilapia, flathead grey mullet, and African catfish) were collected from Manzala Lake, Egypt, and analyzed for determination of heavy metal residues using an atomic absorption spectrophotometer. Metal concentrations (µg/g wet weight) were detected in all examined samples in quantities of 0.045, 0.0145, and 0.017 µg/g for Hg; 0.511, 0.621, and 0.568 µg/g for As; 0.704, 0.635, and 0.64 µg/g for Pb; and 0.024, 0.006, and 0.020 µg/g for Cd in Nile tilapia, flathead grey mullet, and African catfish, respectively. The mean concentrations of Hg, Pb, and Cd among the three fish species tested followed the order Nile tilapia > African catfish > flathead grey mullet; meanwhile, As concentration followed the order flathead grey mullet > African catfish > Nile tilapia. The contamination levels of Hg and Cd showed significant differences between summer and winter in the three different fish species examined. Both the mullet and catfish tested revealed significant negative correlations between fish size and their residual levels of Hg, Pb, and Cd. Health-risk assessment indices suggesting that consuming such fishes from Manzala Lake could have a potential health hazard to consumers.


Assuntos
Lagos/química , Metais Pesados/análise , Poluentes Químicos da Água/análise , Animais , Cádmio/análise , Cádmio/metabolismo , Peixes-Gato/metabolismo , Egito , Monitoramento Ambiental , Peixes/metabolismo , Contaminação de Alimentos/análise , Mercúrio/análise , Mercúrio/metabolismo , Metais Pesados/metabolismo , Medição de Risco , Alimentos Marinhos/análise , Smegmamorpha , Poluentes Químicos da Água/metabolismo
14.
Environ Pollut ; 252(Pt B): 1026-1034, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31252099

RESUMO

Marine fish are considered a source of high quality proteins and fatty acids. However, the consumption of fish may pose a health risk as it may have potentially toxic elements in high concentrations. In this study we quantify the multielemental composition of muscle and fins for three species of commercial marine fish from Brazil: Sphyraena guachancho (Barracuda), Priacantus arenatus (Common bigeye) and Genidens genidens (Guri sea catfish). We then assessed the potential risk of fish consumption by means of a Provisional Hazard Indices. Amongst the elements detected in fish tissue were potentially toxic elements such as Ag, Ba, Cd, Cr and Hg. Concentration differences were species-specific, and affected by the species trophic level, morphological characteristics and feeding habits. Results suggest the higher the trophic level of the fish, the higher the risk of consumption. Caution is recommended for the frequent ingestion of high trophic level fish species in Brazil.


Assuntos
Peixes/metabolismo , Contaminação de Alimentos/análise , Metais Pesados/análise , Alimentos Marinhos/análise , Poluentes Químicos da Água/análise , Nadadeiras de Animais/química , Animais , Brasil , Peixes-Gato/metabolismo , Músculos/química , Perciformes/metabolismo , Medição de Risco
15.
Environ Sci Pollut Res Int ; 26(20): 20610-20618, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31104244

RESUMO

The present study was designed to investigate the protective role of dietary supplementation of Spirulina platensis (SP) against cytotoxic and genotoxic effects of lead nitrate in Clarias gariepinus. Four groups of fishes were used: first group as control which fed on basal diet, second group fed on basal diet and exposed to (1 mg/L of lead nitrate), third group fed on diet containing 0.25% SP and exposed to (1 mg/L of lead nitrate), and fourth group fed on diet containing 0.5%SP and exposed to (1 mg/L of lead nitrate). Fish samples were taken at 2nd and 4th week of exposure. The hematological indices of lead nitrate-exposed group were decreased significantly compared to the control group at 2nd and 4th week of exposure. Lead nitrate caused a significant increase in the percentage of poikilocytosis, micronuclei, and apoptotic cells as well as comet tail length and olive tail moment compared with the control group at 2nd and 4th week of exposure. The highest level of damage was found on 4th week of exposure with all parameters. Dietary inclusion of SP ameliorated these cytotoxic and genetic changes, as well as this amelioration was concentration and time dependent. Consequently, the present study proposed that the addition of SP to the fish diet can be used as a promising protective agent to oppose cytotoxic and genotoxic effects of lead nitrate in aquaculture. Graphical abstract.


Assuntos
Peixes-Gato/metabolismo , Chumbo/toxicidade , Nitratos/toxicidade , Substâncias Protetoras/farmacologia , Spirulina/fisiologia , Poluentes Químicos da Água/toxicidade , Ração Animal/análise , Animais , Biomarcadores/sangue , Peixes-Gato/sangue , Peixes-Gato/genética , Dano ao DNA/efeitos dos fármacos , Suplementos Nutricionais , Chumbo/metabolismo , Nitratos/metabolismo , Substâncias Protetoras/análise , Poluentes Químicos da Água/metabolismo
16.
Fish Physiol Biochem ; 45(4): 1309-1320, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31089992

RESUMO

An experiment was carried out to assess the effect of replacing fishmeal with mopane worm meal in the diet of Clarias gariepinus. Juvenile C. gariepinus weighing 67.04 ± 3 g were stocked in 15 rectangular concrete tanks connected to a recirculating system. Five diets denoted D1, D2, D3, D4 and D5 were formulated to replace fishmeal with mopane worm meal at 0, 10, 20, 40 and 60%. Triplicate groups of C. gariepinus were randomly assigned to each diet at a stocking density of 100 fish per tank. The fish were fed to apparent satiation twice daily for 51 days. All growth performance indices declined with higher mopane worm inclusion levels. Specific growth rate (SGR) declined from 1.85%/day in the control diet to 1.43%/day in diet 5. Protein efficiency ratio (PER) also declined from 25.27% in the control diet to 19.30% in diet 5. Apparent digestibility coefficient (ADC) followed a similar pattern declining from 92.2% in the control diet to 87.1% in diet 5. Both amylase and protease activity in the stomach increased with higher mopane worm inclusion levels. Despite the increased enzyme activity in the stomach, SGR declined. The decline in SGR was attributed to high acid detergent fibre (ADF 58.4 g/kg) and chitin in the mopane worm diets. Lipase and chitinase did not show any discernible pattern with high mopane worm inclusion levels in the stomach. In the intestines, protease, lipase and chitinase did not show any discernible pattern with high mopane worm inclusion levels. Consequently, the relationship between SGR and all these enzymes was weak. However, amylase activity declined with higher mopane worm inclusion levels in the intestines, and this resulted in decreased SGR (r2 = 0.6722). The negative effects of mopane worm meal were further confirmed by the increase in liver degradation scores at high mopane worm inclusion levels. The liver degradation score increased from 1.12 in the control to 2.46 in diet 5.


Assuntos
Ração Animal , Peixes-Gato , Dieta/veterinária , Larva , Mariposas , Amilases/metabolismo , Animais , Peixes-Gato/anatomia & histologia , Peixes-Gato/crescimento & desenvolvimento , Peixes-Gato/metabolismo , Quitinases/metabolismo , Hepatócitos/patologia , Mucosa Intestinal/enzimologia , Lipase/metabolismo , Peptídeo Hidrolases/metabolismo , Estômago/enzimologia
17.
Aquat Toxicol ; 212: 154-161, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31128416

RESUMO

Elevated concentrations of nitrite develop occasionally in various aquatic habitats and aquaculture facilities, providing a potential danger for freshwater fish that take up nitrite via the gill chloride uptake mechanism. We studied the uptake, effects and metabolism of nitrite in blood, heart and skeletal muscle at two temperatures in striped catfish Pangasianodon hypophthalmus, a facultative air-breathing fish that is heavily cultivated in Southeast Asia. Exposure to 0.8 mM ambient nitrite increased blood [nitrite] and [methaemoglobin] (metHb) to high values at day 1, but values subsequently decreased towards controls at day 7. Blood [nitrite] and metHb content were unexpectedly higher at 27 °C (∼1.2 mM; 69% at day 1) than at 33 °C (∼0.9 mM; 55%), reflecting a lower nitrite uptake at the highest temperature, possibly via an increased reliance on air-breathing relative to water-breathing with temperature increase. A large fraction of the nitrite taken up was effectively eliminated by being detoxified to nitrate. Further, erythrocyte metHb reductase activity was increased during nitrite exposure, efficiently reducing metHb to functional haemoglobin. The uptake of nitrite into white skeletal musculature (main part of the fish) was much lower than into heart tissue. While heart [nitrite] was close to blood plasma levels, muscle [nitrite] peaked at ∼0.2 mM at day 1 and subsequently declined to ∼0.05 mM at day 7, which is below levels reported in various commercial cured meat products. Nitrite was partly metabolized to iron-nitrosyl, S-nitroso and N-nitroso compounds. The increase in nitros(yl)ated compounds was marginal in skeletal muscle and more pronounced in heart tissue.


Assuntos
Peixes-Gato , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Nitritos/metabolismo , Nitritos/toxicidade , Temperatura Ambiente , Aclimatação , Animais , Peixes-Gato/metabolismo , Cloretos/metabolismo , Eritrócitos/efeitos dos fármacos , Eritrócitos/enzimologia , Água Doce/química , Coração/efeitos dos fármacos , Hemoglobinas/metabolismo , Metemoglobina/metabolismo , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Miocárdio/química , Nitritos/sangue , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/toxicidade
18.
Mol Cell Proteomics ; 18(7): 1437-1453, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31092672

RESUMO

Heterosis is a complex biological phenomenon in which hybridization produces offspring that exhibit superior phenotypic characteristics compared with the parents. Heterosis is widely utilized in agriculture, for example in fish farming; however, its underlying molecular basis remains elusive. To gain a comprehensive and unbiased molecular understanding of fish heterosis, we analyzed the mRNA, miRNA, and proteomes of the livers of three catfish species, Pelteobagrus fulvidraco, P. vachelli, and their hybrid, the hybrid yellow catfish "Huangyou-1" (P. fulvidraco ♀ × P. vachelli ♂). Using next-generation sequencing and mass spectrometry, we show that the nonadditive, homoeolog expression bias and expression level dominance pattern were readily identified at the transcriptional, post-transcriptional, or protein levels, providing the evidence for the widespread presence of dominant models during hybridization. A number of predicted miRNA-mRNA-protein pairs were found and validated by qRT-PCR and PRM assays. Furthermore, several diverse key pathways were identified, including immune defense, metabolism, digestion and absorption, and cell proliferation and development, suggesting the vital mechanisms involved in the generation of the heterosis phenotype in progenies. We propose that the high parental expression of genes/proteins (growth, nutrition, feeding, and disease resistance) coupled with low parental miRNAs of the offspring, are inherited from the mother or father, thus indicating that the offspring were enriched with the advantages of the father or mother. We provide new and important information about the molecular mechanisms of heterosis, which represents a significant step toward a more complete elucidation of this phenomenon.


Assuntos
Peixes-Gato/genética , Peixes-Gato/metabolismo , Vigor Híbrido/genética , MicroRNAs/metabolismo , Proteômica , Transcriptoma/genética , Animais , Feminino , Regulação da Expressão Gênica , Hibridização Genética , Masculino , MicroRNAs/genética , Modelos Genéticos , Proteoma/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reprodutibilidade dos Testes
19.
Theriogenology ; 131: 61-71, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30947076

RESUMO

The analysis of early gonadogenesis during larval development requires a molecular marker that is specifically expressed in the germ cell lineage, such as the vasa gene. In this study, we cloned and characterized vasa in the striped catfish (Pangasianodon hypophthalmus), and designated this as Phy-vasa. Phy-vasa contained all of the predicted consensus motifs that are shared among the vasa genes in other fish species, including RG and RGG repeats, ATPase motifs, and a DEAD-box, and phylogenetic analysis using various DEAD-box family proteins demonstrated that the Phy-vasa protein clustered within the Vasa family. Reverse transcription polymerase chain reaction (RT-PCR) indicated that Phy-vasa mRNA only occurred in the testis and ovary, and in situ hybridization showed that the gene was expressed only in the germ cells, with strong expression in the spermatogonia and oogonia. To investigate early gonadogenesis in catfish larvae, we undertook histological characterization and in situ hybridization using a Phy-vasa probe, which showed that migration of the primordial germ cells (PGCs) most commonly occurred in larvae at 2-10 days post-fertilization (dpf), the PGCs started to be surrounded by gonadal somatic cells at around 10-20 dpf, and rapid proliferation of the PGCs had begun by 30 dpf. These findings provide a valuable insight into early gonadal development in the striped catfish.


Assuntos
Peixes-Gato/metabolismo , RNA Helicases DEAD-box/metabolismo , Proteínas de Peixes/metabolismo , Células Germinativas/metabolismo , Gônadas/metabolismo , Animais , Peixes-Gato/genética , RNA Helicases DEAD-box/química , Proteínas de Peixes/química , Filogenia , RNA/metabolismo , Alinhamento de Sequência , Análise de Sequência de Proteína
20.
Acta Histochem ; 121(4): 437-449, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30952366

RESUMO

Lepidophagy is comparatively rare amongst teleost fishes, yet our understanding of this specialization is lacking. Therefore we examined the digestive tract features of Pachypterus khavalchor using morphological, osteological, histological and histochemical techniques to comprehend and relate structural organization of digestive tract with scale eating habit. Morphologically, the alimentary canal is defined by a short and muscular esophagus, well-developed stomach and comparatively short intestine. Gut content analysis and intestinal coefficient value (0.53 ± 0.01) revealed that P. khavalchor exhibit both carnivory and lepidophagy. However, P. khavalchor primarily feeds on the scales (67.47%) and other chitin-rich material like aquatic insects (17.62%), aquatic larvae (8.66%) which affirms its solid association with chitinase producing endosymbionts in the gut. Lepidophagy is further supported by the osteological observations. The perfect segregation of the functions such as food capture, ingestion and processing amongst the different types of teeth located in the oral cavity and pharyngeal region thus could be taken as evolutionary adaptations in scale eaters to support lepidophagy. Specialized arrangement of the esophageal and stomach epithelial folds could be altogether taken as an adaptation with the end goal to frame the scale stacks and accordingly facilitate the handling and processing of chitin-rich bolus. The esophageal mucosa is simple squamous epithelium instead of stratified epithelium with numerous goblet cells to withstand the mechanical harm by hard-food stuff like scales. The cardiac and fundic regions exhibited large number tubular gastric glands with simple columnar epithelium. Surface cells of all three stomach regions stained positive for PAS staining. The intestine is without pyloric caeca and is divided into anterior and posterior region. Histologically it is characterized by simple columnar epithelium with brush border and numerous goblet cells throughout its length. Presence of large number microvilli on anterior and posterior intestine was noticeable. Intestinal goblet cells reacted positively to PAS, AB (pH 1) and AB (pH 2.5). Secretions of goblet cells are important for lubricating and protecting the epithelium. The results of present investigation improve the understanding of the digestive physiology of scale eaters in general and P. khavalchor in particular. Overall, our data indicates that though P. khavalchor predominantly feeds on scale, the digestive physiology is adapted to support dual feeding habit (lepidophagy and carnivory).


Assuntos
Peixes-Gato/anatomia & histologia , Peixes-Gato/fisiologia , Comportamento Alimentar/fisiologia , Trato Gastrointestinal/anatomia & histologia , Trato Gastrointestinal/fisiologia , Animais , Peixes-Gato/metabolismo , Quitina/metabolismo , Feminino , Mucinas Gástricas/metabolismo , Células Caliciformes/citologia , Células Caliciformes/fisiologia , Masculino
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