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1.
BMC Biol ; 21(1): 72, 2023 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-37024917

RESUMO

BACKGROUND: Bdelloid rotifers are micro-invertebrates distributed worldwide, from temperate latitudes to the most extreme areas of the planet like Antarctica or the Atacama Desert. They have colonized any habitat where liquid water is temporarily available, including terrestrial environments such as soils, mosses, and lichens, tolerating desiccation and other types of stress such as high doses of ionizing radiation (IR). It was hypothesized that bdelloid desiccation and radiation resistance may be attributed to their potential ability to repair DNA double-strand breaks (DSBs). Here, these properties are investigated and compared among nine bdelloid species collected from both mild and harsh habitats, addressing the correlation between the ability of bdelloid rotifers to survive desiccation and their capacity to repair massive DNA breakage in a phylogenetically explicit context. Our research includes both specimens isolated from habitats that experience frequent desiccation (at least 1 time per generation), and individuals sampled from habitats that rarely or never experienced desiccation. RESULTS: Our analysis reveals that DNA repair prevails in somatic cells of both desiccation-tolerant and desiccation-sensitive bdelloid species after exposure to X-ray radiation. Species belonging to both categories are able to withstand high doses of ionizing radiation, up to 1000 Gy, without experiencing any negative effects on their survival. However, the fertility of two desiccation-sensitive species, Rotaria macrura and Rotaria rotatoria, was more severely impacted by low doses of radiation than that of desiccation-resistant species. Surprisingly, the radioresistance of desiccation-resistant species is not related to features of their original habitat. Indeed, bdelloids isolated from Atacama Desert or Antarctica were not characterized by a higher radioresistance than species found in more temperate environments. CONCLUSIONS: Tolerance to desiccation and radiation are supported as ancestral features of bdelloid rotifers, with a group of species of the genus Rotaria having lost this trait after colonizing permanent water habitats. Together, our results provide a comprehensive overview of the evolution of desiccation and radiation resistance among bdelloid rotifers.


Assuntos
Dessecação , Rotíferos , Humanos , Animais , Rotíferos/genética , Quebras de DNA de Cadeia Dupla , Reparo do DNA , Água
2.
Fish Shellfish Immunol ; 128: 620-633, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36038101

RESUMO

This study aimed to determine to what extend the addition of chitinase to black soldier fly larvae (BSF) meals enriched with either PUFA or LC-PUFA could improve the gut health of Nile tilapia and increase its immune status. Two types of BSF meals enriched with either α-linolenic acid (ALA) or ALA + eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA) were produced using BSF larvae cultured on vegetable substrates (VGS) or fish offal substrates (FOS), respectively. Seven diets were formulated: a control FMFO diet and two other control diets VGD0 vs FOD0 containing the meals of each type of BSF meal as total replacement for fishmeal (FM) and fish oil (FO), as well as four diets supplemented with chitinase. Two doses of commercial chitinase from Aspergillus niger (2 g/kg and 5 g/kg of feed) were supplemented to the other diets VGD0 and FOD0 to formulate VGD2, VGD5, FOD2 and FOD5. After 53 days of feeding, FOD5 diet induced a similar growth performance as the FMFO control diet, while a significant decrease of growth was observed for the other BSF larval-based diets. BSF/FOS meal led to higher SGR of fish than BSF/VGS, as for the FOD5 compared to VGD5. At day 53, lysozyme values showed an increasing trend in fish fed all the BSF-based diets, especially those fed the VGD5. After the Escherichia coli lipopolysaccharide (LPS) injection (day 54), the same increasing trend was observed in lysozyme activity, and modulation was observed only in the VGD5 fish. ACH50 activity was reduced by the BSF-based diets except for the FOD5 diet at day 53, and LPS modulation was only observed for the VGS-chitinase-based diets at day 54. Peroxidase activity and total immunoglobulin (Igs) blood level were not affected by substrate, chitinase dose or LPS injection. At day 53, the low or high dose of chitinase increased the expressions of tlr2, il-1ß and il-6 genes in the head kidney of fish fed the BSF/VGS diets compared to those fed the VGD0 or FMFO control diets. At day 54 after LPS injection, the high dose of chitinase decreased the expressions of tlr5 gene in the spleen and mhcII-α gene in the head kidney of fish fed FOD5 diets compared to those fed FOD0 diets. BSF/VGS but not BSF/FOS based diets increased fish sub-epithelial mucosa (SM) and lamina propria (LP) thickness and the number of goblet cells (GC) in fish, but dietary chitinase seemed to prevent some of these effects, especially at low dose. Results showed that chitinase supplementation of 5 g/kg of chitinase to a BSF-based diet enriched with LC-PUFA improved growth, prevented histological changes in the proximal intestine and enhanced some innate immune functions of Nile tilapia without any clear booster effect after challenge with E. coli LPS.


Assuntos
Quitinases , Ciclídeos , Dípteros , Ração Animal/análise , Animais , Dieta/veterinária , Suplementos Nutricionais , Ácidos Docosa-Hexaenoicos , Ácido Eicosapentaenoico , Escherichia coli , Óleos de Peixe , Imunidade , Imunoglobulinas , Interleucina-6 , Larva , Lipopolissacarídeos/farmacologia , Refeições , Muramidase , Peroxidases , Receptor 2 Toll-Like , Receptor 5 Toll-Like , Ácido alfa-Linolênico
3.
Fish Shellfish Immunol ; 112: 143-150, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33741521

RESUMO

The melatonin hormone, which is a multifunctional molecule in vertebrates, has been shown to exert complex actions on the immune system of mammals. In teleosts, the immunomodulatory capacity of this hormone has seldom been investigated. In the present experiment, we exposed ex vivo spleen and head kidney tissues of pike-perch to melatonin (Mel) and cortisol (Cort). We applied three concentrations of both hormones, alone and in combination, namely (1) Mel (10, 100 or 1000 pg mL-1) (2) Cort (50, 500 or 5000 ng mL-1) (3) Mel + Cort (10 + 50, 100 + 500 or 1000 pg mL-1+5000 ng mL-1). Pure medium without Mel or Cort served as control. After 15 h of incubation, we assessed the expression of a set of immunity-related genes, including genes encoding for pro-inflammatory proteins (il-1ß, cxcl8 and tnf-α), acute-phase proteins (fgl2, fth1, hepc, hp and saa1) and key factors of the adaptive immune system (fκbp4 and tcrg). Both Mel and Cort, when used alone or combined at physiological concentrations, significantly influenced immune gene expressions that may lead to a global immune stimulation. Our results support both, an indirect action of the Mel hormone on the immune system through the regulation of intermediates such as Cort, as well as a direct action on immune targets through specific receptors.


Assuntos
Imunidade Adaptativa , Rim Cefálico/imunologia , Imunidade Inata , Melatonina/administração & dosagem , Percas/imunologia , Baço/imunologia , Imunidade Adaptativa/efeitos dos fármacos , Animais , Rim Cefálico/efeitos dos fármacos , Imunidade Inata/efeitos dos fármacos , Baço/efeitos dos fármacos
4.
Artigo em Inglês | MEDLINE | ID: mdl-33352260

RESUMO

Hydropower plants (HPPs) are a source of "green" energy but also a threat to migrating fish such as the European eel (Anguilla anguilla) owing to the disruption of river connectivity and the obstruction of downstream migration. The impact of HPP are well-documented in terms of fish survival and damages but there is no available information concerning the condition of surviving and unharmed fish. The aim of this study is to assess the impact of the passage through HPP on the survival, the physiological and health status of adult eels. Two trials were carried with variants of the Kaplan turbine - one of the most common types in Europe. After a deliberate passage through the turbines, we studied direct mortality, external and internal damages, stress and immune biomarkers such as plasma cortisol and glucose levels, alternative complement (ACH50), lysozyme and peroxidase activities, and total immunoglobulin (Ig) content. Our results showed a lower survival and a higher external and internal damages rates in the HPP groups. Glucose levels, ACH50, lysozyme and peroxidase activities and TIgc were also affected by the passage depending on HPP characteristics. Those findings suggest a greater energy expenditure and a disruption in innate immunity due to this passage. HPPs can not only have an impact in terms of direct mortality and injuries but also affect the physiological and health condition of the surviving eels. This impact may explain the delayed mortality observed in telemetric studies and the passage through many HPPs may compromise the ability of adult eels to migrate successfully to the ocean.


Assuntos
Anguilla/fisiologia , Migração Animal , Espécies em Perigo de Extinção , Centrais Elétricas , Animais , Glicemia/análise , Meio Ambiente , Hidrocortisona/sangue , Imunidade Humoral , Imunoglobulinas/sangue , Muramidase , Oceanos e Mares , Rios , Estresse Fisiológico
5.
Fish Physiol Biochem ; 47(4): 979-997, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33974164

RESUMO

In stocking program, the use of artificial incubation conditions in hatcheries from the fertilisation of eggs to the release of unfed fry could reduce their ability to adapt to the natural environment. This study evaluates the effects of three factors on the fitness and physiology of salmon fry at their emergence, the origin of water (river vs drilling), the type of support in the incubator (support matrix vs plastic sheets) and the type of incubators (Californian vs vertical trays), and compares them to a semi-natural incubation method in river. Key biological functions including nutritional and immune status were compared among experimental conditions using biometric parameters, lipid composition and gene expression analyses. Our findings demonstrated that fry incubated in vertical trays supplied with river water had no significant difference in growth and lipid composition compared to those in semi-natural incubators. Besides, fry incubated on a substrate matrix in Californian trays exhibited phenotypic characteristics closest to those incubated in river. This support matrix improved fish growth, lipid consumption and distribution compared to fry on plastic sheets. Moreover, the large amounts of several PUFAs in these fry could allow a better membrane fluidity ensuring a better adaptation to temperature variation under cold conditions. In addition, drilling water improved the survival rate compared to river water due to lower numbers of fine particles, known to be responsible for the clogging of eggs. To conclude, using a substrate combined with drilling water in artificial incubators could increase fry fitness and its adaption to wild life.


Assuntos
Pesqueiros , Metabolismo dos Lipídeos , Salmo salar , Animais , Feminino , Expressão Gênica , Masculino , Rios , Salmo salar/genética , Salmo salar/crescimento & desenvolvimento , Salmo salar/metabolismo , Temperatura , Água
6.
Artigo em Inglês | MEDLINE | ID: mdl-32165323

RESUMO

Exposure to a temperature increase may disrupt smoltification and delay or stop the downstream migration of smolts. Thermal regimes are often different between a river and its tributaries, but the effects of a relative temperature shift are not well described. We used expression of smoltification genes coupled with gill Na+/K+-ATPase activity (NKA) and plasma cortisol and growth hormone (GH) levels to investigate the impact of a 5 °C difference between tributary and river on salmon juveniles. Responses to a temperature challenge were examined at four time points during the smoltification period, with juveniles reared under three regimes including control, early and late temperature increase. The temperature shifts reduced gill NKA, plasma GH and cortisol levels which indicate hypo-osmoregulation impairment and may reduce the survival of smolts. Out of the 22 genes examined, the expression of six genes was influenced by the temperature treatments, while changes in further eleven genes were influenced by the date of sampling. Genes usually known to be upregulated during smoltification were downregulated after the temperature increase, notably nkaα1b, nkcc1a and igf1r. Upregulation of some genes involved in the hormonal regulation and acid-base equilibrium in early June may indicate a switch towards desmoltification. This study gives further insights about the impact of temperature increase on the molecular processes underlying smoltification and possible responses to human-related water temperature increase. The data also suggest dual roles in the smoltification and desmoltification for GH and IGF1 and points to the implication of genes in the smoltification process, that have previously been unstudied (nbc) or with little data available (igf2).


Assuntos
Brânquias/fisiologia , Salmo salar/fisiologia , Aclimatação/fisiologia , Migração Animal , Animais , Fator de Crescimento Insulin-Like I/metabolismo , Fator de Crescimento Insulin-Like II/metabolismo , Osmorregulação , Salmo salar/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo , Temperatura , Equilíbrio Hidroeletrolítico
7.
Artigo em Inglês | MEDLINE | ID: mdl-32535234

RESUMO

Atlantic salmon is an anadromous species migrating from upper-reach nursery areas in rivers to the oceanic feeding areas at smolt stage and inversely at adult stage requiring unimpeded migration routes. However, dams associated with hydroelectric power plants (HPP) disrupt river connectivity and affect fish movement and survival. The objective of the current study was to evaluate the short and mid-term physiological and immune response of Atlantic salmon smolts after passing through Andenne HPP (Meuse River, Belgium). Several parameters were studied after an in situ deliberate passage including direct mortality and external damages, stress and immune biomarkers as plasma cortisol and glucose levels, complement and peroxidase activities, and immune and oxidative stress related gene expression 24 h, 72 h and 120 h after passage. Survival rate was lower and external damages were more important in fish that confronted the HPP compared to the control ones. Moreover, the passage through the turbine affected plasma glucose levels, complement and peroxidase activities and the expression of some immune genes such as lysg, igm and mpo in a timely manner suggesting that this passage can lead to a great energy expenditure and a disruption of innate immunity. Our observations can partially explain the delayed mortality observed in many studies leading to a poor success of restocking programs. HPPs not only have a direct impact in terms of mortalities and injuries but also an indirect one in terms of physiological and immune changes that can compromise Atlantic salmon smolts ability to escape successfully to the ocean.


Assuntos
Adaptação Biológica/fisiologia , Migração Animal/fisiologia , Centrais Elétricas , Salmo salar/fisiologia , Animais , Bélgica , Oceanos e Mares , Rios
8.
Fish Shellfish Immunol ; 92: 288-299, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31195114

RESUMO

Omnivorous fish species such as the common carp (Cyprinus carpio) are able to biosynthesise long chain polyunsaturated fatty acids (LC-PUFAs) from plant oil PUFA precursors, but the influence of the amount and quality of the LC-PUFAs biosynthesised from these oils on the immunocompetence status of the fish has received little attention. This study aims to evaluate whether the conversion of PUFA by carp induces a sufficient biosynthesis of LC-PUFA to maintain a good immunocompetence status in this species. Six iso-nitrogenous (crude protein = 39.1%) and iso-lipidic (crude lipids = 10%) diets containing three different lipid sources (cod liver oil (CLO) as fish oil; linseed oil (LO) and sunflower oil (SFO) as plant oils) were formulated with or without ß-glucan supplementation at 0.25 g/kg diet. Juvenile carp (16.3 ±â€¯0.6 g initial body weight) were fed a daily ration of 4% body weight for 9 weeks and then infected at day 64 with the bacteria Aeromonas hydrophyla. No significant differences in survival rate, final body weight, specific growth rate and feed conversion rate were observed between diets. After bacterial infection, mortality rate did not differ between fish fed CLO and plant oil-based diets, indicating that the latter oils did not affect the overall immunocompetence status of common carp. Plant oil-based diets did not alter lysozyme activity in healthy and infected fish. No negative effects of plant oils on complement activity (ACH50) were observed in healthy fish, even if both plant oil-based diets induced a decrease in stimulated fish two days after infection. Furthermore, the levels of various immune genes (nk, lys, il-8, pla, pge, alox) were not affected by plant oil-based diets. The expression of pla and pge genes were higher in SFO-fed fish than in CLO ones, indicating that this plant oil rich in linoleic acid (LA) better stimulated the eicosanoid metabolism process than fish oil. In response to ß-glucan supplementation, some innate immune functions seemed differentially affected by plant oil-based diets. LO and SFO induced substantial LC-PUFA production, even if fish fed CLO displayed the highest EPA and DHA levels in tissues. SFO rich in LA induced the highest ARA levels in fish muscle while LO rich in α-linolenic acid (ALA) sustained higher EPA production than SFO. A significantly higher fads-6a expression level was observed in SFO fish than in LO ones, but this was not observed for elovl5 expression. In conclusion, the results show that common carp fed plant oil-based diets are able to produce substantial amounts of LC-PUFA for sustaining growth rate, immune status and disease resistance similar to fish fed a fish oil-based diet. The differences in the production capacity of LC-PUFAs by the two plant oil-based diets were associated to a differential activation of some immune pathways, explaining how the use of these oils did not affect the overall immunocompetence of fish challenged with bacterial infection. Moreover, plant oil-based diets did not induce substantial negative effects on the immunomodulatory action of ß-glucans, confirming that these oils are suitable for sustaining a good immunocompetence status in common carp.


Assuntos
Carpas/imunologia , Imunocompetência/efeitos dos fármacos , Óleos de Plantas/metabolismo , beta-Glucanas/metabolismo , Ração Animal/análise , Animais , Carpas/crescimento & desenvolvimento , Dieta/veterinária , Suplementos Nutricionais/análise , Ácidos Graxos Insaturados/metabolismo , Óleos de Peixe/administração & dosagem , Proteínas de Peixes/imunologia , Proteínas de Peixes/metabolismo , Óleos de Plantas/administração & dosagem , Distribuição Aleatória , beta-Glucanas/administração & dosagem
9.
Fish Shellfish Immunol ; 71: 359-371, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29050988

RESUMO

Lactoferrin, a large multifunctional glycoprotein, is involved in many physiological functions but its immunomodulatory pathways are not well characterized in fish. The objective of the present study was to investigate the temporal effect of dietary bovine lactoferrin (BLf) at low (0.1%) and high (1%) on immunological organs of rainbow trout juveniles. BLf diets did not affect specific growth rate, haematocrit, splenic index, spleen respiratory burst activity as well as humoral (mIgM) and neutrophils (MPO) gene expressions after short term - 35 days (D35) and long term nutrient test - 51 days (D51) of feeding. Both low and high BLf doses induced enhanced level of plasma alternative complement activity, plasma total immunoglobulin on D35 and D51, lymphocyte plus thrombocyte cell proportion on D35 and monocyte cell proportion in total blood leukocyte cells on D51. On D51 but not on D35, BLf diets upregulated the expression of inflammatory genes in kidney for il-1 at the low BLf dose, il-8 at both BLf doses and il-6 at the high BLf dose in spleen, and il-10 at both BLf doses in kidney. Moreover, the expression of T helper (cd4-2α; cd4-2ß) genes was significantly upregulated only on D51 by both BLf doses in both spleen and kidney tissues. On D51, controls and BLf treated fish were intraperitoneally injected with A. salmonicida achromogenes. The expression of 13 immune genes was evaluated at 44 h post-injection (D54). The expression of lysozyme gene was upregulated by both BLf doses after bacterial infection both in spleen and kidney. The expression of mcsfrα (spleen) and tgf-ß1 (kidney) was also modulated by both BLf doses. Low and high BLf doses enhanced disease resistance of rainbow trout juveniles with the cumulative survival rate of 36% and 38% respectively while those of the control was 19% after 14 days challenged with bacteria. The results indicate that BLf diets activated the humoral immunity, associated to blood leukocyte cells of rainbow trout after short term BLf administration, and the long term BLf administration was necessary for sensitizing other lymphoid organs such as in spleen and kidney. Only after long term test, BLf diets induced significantly higher levels of innate and adaptive immune gene expressions than those of the control. Dietary BLf activated more markedly the expression of innate immune genes than the adaptive ones; this upregulation of some immune genes could explain the high disease resistance observed in rainbow trout juveniles fed BLf.


Assuntos
Anti-Infecciosos/farmacologia , Resistência à Doença/imunologia , Doenças dos Peixes/imunologia , Imunidade Humoral , Lactoferrina/farmacologia , Leucócitos/imunologia , Oncorhynchus mykiss/imunologia , Administração Oral , Aeromonas salmonicida/fisiologia , Ração Animal/análise , Animais , Anti-Infecciosos/administração & dosagem , Dieta/veterinária , Relação Dose-Resposta Imunológica , Expressão Gênica/imunologia , Perfilação da Expressão Gênica/veterinária , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , Lactoferrina/administração & dosagem , Oncorhynchus mykiss/genética , Oncorhynchus mykiss/crescimento & desenvolvimento , Fatores de Tempo
10.
J Proteome Res ; 15(1): 48-67, 2016 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-26632866

RESUMO

Cephalopods exhibit a wide variety of behaviors such as prey capture, communication, camouflage, and reproduction thanks to a complex central nervous system (CNS) divided into several functional lobes that express a wide range of neuropeptides involved in the modulation of behaviors and physiological mechanisms associated with the main stages of their life cycle. This work focuses on the neuropeptidome expressed during egg-laying through de novo construction of the CNS transcriptome using an RNAseq approach (Illumina sequencing). Then, we completed the in silico analysis of the transcriptome by characterizing and tissue-mapping neuropeptides by mass spectrometry. To identify neuropeptides involved in the egg-laying process, we determined (1) the neuropeptide contents of the neurohemal area, hemolymph (blood), and nerve endings in mature females and (2) the expression levels of these peptides. Among the 38 neuropeptide families identified from 55 transcripts, 30 were described for the first time in Sepia officinalis, 5 were described for the first time in the animal kingdom, and 14 were strongly overexpressed in egg-laying females as compared with mature males. Mass spectrometry screening of hemolymph and nerve ending contents allowed us to clarify the status of many neuropeptides, that is, to determine whether they were neuromodulators or neurohormones.


Assuntos
Neuropeptídeos/metabolismo , Neurotransmissores/metabolismo , Oviposição , Sepia/fisiologia , Sequência de Aminoácidos , Animais , Feminino , Anotação de Sequência Molecular , Dados de Sequência Molecular , Neuropeptídeos/química , Neuropeptídeos/genética , Neurotransmissores/química , Neurotransmissores/genética , Especificidade de Órgãos , Proteoma/química , Proteoma/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transcriptoma
11.
Aquat Toxicol ; 272: 106981, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38843740

RESUMO

The increasing release of engineered nanoparticles (ENPs) in aquatic ecosystems stresses the need for stringent investigations of nanoparticle mixture toxicity towards aquatic organisms. Here, the individual and combined immunotoxicity of two of the most consumed ENPs, the ZnO and the TiO2 ones, was investigated on rainbow trout juveniles (Oncorhynchus mykiss). Fish were exposed to environmentally realistic concentrations (21 and 210 µg L-1 for the ZnO and 210 µg L-1 for the TiO2) for 28 days, and then challenged with the pathogenic bacterium, Aeromonas salmonicida achromogenes. Antioxidant and innate immune markers were assessed before and after the bacterial infection. None of the experimental conditions affected the basal activity of the studied innate immune markers and the redox balance. However, following the bacterial infection, the expression of genes coding for pro and anti-inflammatory cytokines (il1ß and il10), as well as innate immune compounds (mpo) were significantly reduced in fish exposed to the mixture. Conversely, exposure to ZnO NPs alone seemed to stimulate the immune response by enhancing the expression of the IgM and c3 genes for instance. Overall, our results suggest that even though the tested ENPs at their environmental concentration do not strongly affect basal immune functions, their mixture may alter the development of the immune response when the organism is exposed to a pathogen by interfering with the inflammatory response.


Assuntos
Aeromonas salmonicida , Infecções por Bactérias Gram-Negativas , Oncorhynchus mykiss , Titânio , Poluentes Químicos da Água , Óxido de Zinco , Animais , Aeromonas salmonicida/efeitos dos fármacos , Óxido de Zinco/toxicidade , Oncorhynchus mykiss/imunologia , Oncorhynchus mykiss/microbiologia , Titânio/toxicidade , Poluentes Químicos da Água/toxicidade , Infecções por Bactérias Gram-Negativas/veterinária , Infecções por Bactérias Gram-Negativas/imunologia , Imunidade Inata/efeitos dos fármacos , Nanopartículas/toxicidade , Doenças dos Peixes/imunologia , Doenças dos Peixes/microbiologia , Nanopartículas Metálicas/toxicidade , Citocinas/genética , Citocinas/metabolismo
12.
Environ Pollut ; 351: 124094, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38703983

RESUMO

The chorion is the first protective barrier set to prevent numerous pollutants from damaging the developing embryo. However, depending on their size, some nanoplastics (NPs) can pass through this barrier and reach the embryo, while all microplastics (MPs) remain on the outside. This study brings a straight approach to compare MPs and NPs, and assess their direct and indirect effects on zebrafish embryos and larvae. Zebrafish eggs were exposed before 2 h post fertilization (hpf) to polystyrene MPs (5 µm) and NPs (250 nm) at a concentration of 1000 µg/L until 96 hpf. Physiotoxicity and neurotoxicity were assessed prior and post-hatching through several biomarkers. Response to hypoxia (upregulation of hif-1aa and hif-1ab) were found in embryos exposed to MPs, and partly found in those exposed to NPs. Embryos exposed to NPs showed significant tachycardia, reduced O2 consumption and increased apoptosis in the eyes, whereas MPs affected the expressions of all genes related to the neurodevelopment of embryos (elavl3, pax2a, pax6a, act1b). Post-hatching, physiological responses were muted. MPs and NPs exposures ended by evaluating larval behaviours during dark-and-light cycles. Both sizes of plastic particles negatively affected the visual motor response (VMR) and vibrational startle response (VSR). Thigmotaxis levels were significantly increased by NPs whereas MPs showed anxiolytic properties. This study shows that both MPs and NPs affect the physiology and neurodevelopment of zebrafish at different levels, before and after hatching.


Assuntos
Embrião não Mamífero , Microplásticos , Poluentes Químicos da Água , Peixe-Zebra , Animais , Peixe-Zebra/fisiologia , Microplásticos/toxicidade , Poluentes Químicos da Água/toxicidade , Embrião não Mamífero/efeitos dos fármacos , Tamanho da Partícula , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Plásticos/toxicidade , Nanopartículas/toxicidade
13.
Chemosphere ; 350: 141107, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38171397

RESUMO

The plastisphere is a newly recognized ecosystem. However, its interaction with early life stages of aquatic vertebrates is a multifaceted issue that requires further research. This study investigated the involvement of bacteria in shaping realistic microplastics hazards in zebrafish Danio rerio embryos. Fish were exposed to bottle micro-fragments (FR) and textile micro-fibers (FI) of polyethylene terephthalate (5-15 µm), concomitant with Aeromonas salmonicida achromogenes challenge from 2h post-fertilization for 3 days. Egg chorion showed affinity for FR and FI, inducing earlier embryo hatching. However, this effect was masked by biofilm invasion. Fragments were more detrimental than fibers on developmental parameters, while bacterial presence compromised body length, eye, and yolk sac surface area. In a further finding, MPs alone increased locomotor activity in zebrafish larvae, without synergistic effect when combined with bacteria. Data showed that realistic MPs had no significant effects except for downregulated sod and cyp1a gene expression, whereas bacterial challenge inhibited larval potency for most of the evaluated mRNA levels (mpx (immune system), apoeb (lipid metabolism), nfkb and tfa (inflammation), cyp and sod (oxidative stress)). This study provides new insights into realistic microplastic effects under relevant conditions when combined with environmental pathogen within the first life stages of aquatic vertebrates.


Assuntos
Microplásticos , Poluentes Químicos da Água , Animais , Microplásticos/toxicidade , Microplásticos/metabolismo , Peixe-Zebra/genética , Plásticos/metabolismo , Embrião não Mamífero , Ecossistema , Perfilação da Expressão Gênica , Poluentes Químicos da Água/metabolismo , Larva
14.
Aquat Toxicol ; 271: 106941, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38723469

RESUMO

OBJECTIVE: To characterise and compare the toxicity of estetrol (E4) and 17α-ethinylestradiol (EE2), and their respective mixture with the progestin drospirenone (DRSP) in zebrafish (Danio rerio) embryos. METHODS: Zebrafish embryos were exposed to E4, EE2, DRSP, E4+DRSP, and EE2+DRSP in a fish embryo acute toxicity (FET) test. A second test examined behavioural responses and, using label-free proteomics, identified changes in protein expression in response to hormonal treatments, across a range of concentrations, including those that are considered to be environmentally relevant. RESULTS: In the FET test, no effects were found from E4 at concentrations ≤100 mg/L, while EE2 induced mortality and morphological abnormalities at concentrations of 1-2 mg/L. In the behavioural test, exposure to 30 ng/L EE2 (∼200 × predicted environmental concentration - PEC) resulted in hypoactivity in fish larvae and exposure to 0.3 ng/L EE2 (∼2 × PEC) led to quantitative changes in protein abundance, revealing potential impacts on RNA processing and protein synthesis machinery. Exposure to E4 did not alter behaviour, but several groups of proteins were modulated, mainly at 710 ng/L (∼200 × PEC), including proteins involved in oxidative phosphorylation. When combined with DRSP, EE2 induced reduced effects on behaviour and proteomic responses, suggesting an antagonistic effect of DRSP. E4+DRSP induced no significant effects on behaviour or proteomic profiles at tested concentrations. CONCLUSIONS: These findings suggest that E4-based combined oral contraceptives present a more favourable environmental profile than EE2-based contraceptives, particularly during the early developmental stages of fish.


Assuntos
Androstenos , Comportamento Animal , Etinilestradiol , Larva , Proteômica , Poluentes Químicos da Água , Peixe-Zebra , Animais , Etinilestradiol/toxicidade , Poluentes Químicos da Água/toxicidade , Androstenos/toxicidade , Comportamento Animal/efeitos dos fármacos , Larva/efeitos dos fármacos , Embrião não Mamífero/efeitos dos fármacos
15.
Microorganisms ; 11(2)2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36838503

RESUMO

Environmental stressors can disrupt the relationship between the microbiota and the host and lead to the loss of its functions. Among them, bacterial infection caused by Aeromonas salmonicida, the causative agent of furunculosis, results in high mortality in salmonid aquaculture. Here, rainbow trout were exposed to A. salmonicida achromogenes and its effects on the taxonomic composition and structure of the microbiota was assessed on different epithelia (gills, skin, and caudal fin) at 6 and 72 h post-infection (hpi) using the V1-V3 region of the 16S rRNA sequencing. Moreover, the infection by the pathogen and immune gene responses were evaluated in the head kidney by qPCR. Our results suggested that α-diversity was highly diverse but predominated by a few taxa while ß-diversity was affected very early by infection in the gills after 6 h, subsequently affecting the microbiota of the skin and caudal fin. A dysbiosis of the microbiota and an increase in genera known to be opportunistic pathogens (Aeromonas, Pseudomonas) were also identified. Furthermore, an increase in pro-inflammatory cytokines and virulence protein array (vapa) was observed in trout head kidney as soon as 6 hpi and remained elevated until 72 hpi, while the anti-inflammatory genes seemed repressed. This study suggests that the infection by A. salmonicida achromogenes can alter fish microbiota of gills in the few hours post-infection. This result can be useful to develop a non-invasive technique to prevent disease outbreak in aquaculture.

16.
Chemosphere ; 311(Pt 1): 136969, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36306963

RESUMO

Although the hazards of microplastics (MPs) have been explored, no complete data exists on the effect of MPs on the egg chorion. This study aims to evaluate the modification of immune responses, metabolism, and behavior of zebrafish larvae (Danio rerio) depending on the moment of exposure. Larvae were exposed to 5 µm polystyrene microbeads at a concentration of 0, 100, or 1000 µg/l, according to a specified times of exposure (0-4, 4-8, 0-8 days postfertilization (dpf)), followed by a bacterial challenge at 8 dpf. After every 4 and 8 dpf, swimming activity, gene expression related to oxidative stress and immune system responses were assessed. During embryonic development, larvae exposed to a concentration of 1000 µg/l MPs already showed a significantly reduced tail coiling frequency, yolk sac resorption and heartbeat. At 8 dpf, swimming activity was altered, even without ingestion and a few days after the end of MP exposure. Our results indicated a difference in immune system (nfkb, il1ß) and apoptosis (casp3a, bcl2) related gene expression depending on the timing of MP exposure, which highlighted a contrasting sensitivity according to the exposure time in MP studies. This study brings new insight into how MPs might affect zebrafish larvae health and development even without ingestion.


Assuntos
Infecções Bacterianas , Poluentes Químicos da Água , Animais , Microplásticos/toxicidade , Peixe-Zebra/metabolismo , Plásticos/metabolismo , Larva , Imunidade Inata , Poluentes Químicos da Água/metabolismo
17.
Aquat Toxicol ; 259: 106505, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37058791

RESUMO

Natural and synthetic oestrogens are commonly found in aquatic ecosystems. The synthetic oestrogen 17α-ethinylestradiol (EE2) is widely used in oral contraceptives and its ecotoxicological effects on aquatic organisms have been widely reported. The natural oestrogen estetrol (E4) was recently approved for use in a new combined oral contraceptive and, after therapeutic use, is likely to be found in the aquatic environment. However, its potential effects on non-target species such as fish is unknown. In order to characterize and compare the endocrine disruptive potential of E4 with EE2, zebrafish (Danio rerio) were exposed to E4 or EE2 in a fish short-term reproduction assay conducted according to OECD Test Guideline 229. Sexually mature male and female fish were exposed to a range of concentrations, including environmentally relevant concentrations of E4 and EE2, for 21 days. Endpoints included fecundity, fertilization success, gonad histopathology, head/tail vitellogenin concentrations, as well as transcriptional analysis of genes related to ovarian sex steroid hormones synthesis. Our data confirmed the strong impact of EE2 on several parameters including an inhibition of fecundity, an induction of vitellogenin both in male and female fish, an alteration of gonadal structures and the modulation of genes involved in sex steroid hormone synthesis in female fish. In contrast, only few significant effects were observed with E4 with no impact on fecundity. The results suggest that the natural oestrogen, E4, presents a more favorable environmental profile than EE2 and is less likely to affect fish reproductive capacity.


Assuntos
Estetrol , Poluentes Químicos da Água , Animais , Masculino , Feminino , Peixe-Zebra/fisiologia , Etinilestradiol/toxicidade , Estetrol/farmacologia , Vitelogeninas , Ecossistema , Poluentes Químicos da Água/toxicidade , Reprodução , Estrogênios/toxicidade
18.
Anesthesiology ; 116(4): 824-33, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22343498

RESUMO

BACKGROUND: The authors investigated the effect of pravastatin during reoxygenation after myocardial hypoxia and examined the involvement of nitric oxide synthase, mitochondrial permeability transition pore, and expression of markers of apoptosis in human myocardium in vitro. METHODS: Human atrial trabeculae were exposed to hypoxia for 30 min and reoxygenation for 60 min (control group; n = 10). Pravastatin (5, 10, 50, 75 µM; n = 6 in each group) was administered throughout the reoxygenation. In separate groups (n = 6 in each group), pravastatin 50 µM was administered in the presence of 200 µM L-NG-nitroarginine methyl ester, a nitric oxide synthase inhibitor, and 50 µM atractyloside, the mitochondrial permeability transition pore opener. The primary endpoint was the developed force of contraction at the end of reoxygenation, expressed as a percentage of baseline (mean ± SD). Protein expression of BAD, phospho-BAD, caspase 3, Pim-1 kinase, and Bcl-2 were measured using Western immunoblotting. RESULTS: The administration of 10 (77 ± 5% of baseline), 50 (86 ± 6%), and 75 µM (88 ± 13%) pravastatin improved the force of contraction at the end of reoxygenation, compared with that of the control group (49 ± 11%; P < 0.001). These beneficial effects were prevented by L-NG-nitroarginine methyl ester and atractyloside. Compared with control group, the administration of 5 µM pravastatin did not modify the force of contraction. Pravastatin increased the phosphorylation of BAD, activated the expression of Pim-1 kinase and Bcl-2, and maintained the caspase 3 concentration relative to that of the respective untreated controls. CONCLUSIONS: Pravastatin, administered at reoxygenation, protected the human myocardium by preventing the mitochondrial permeability transition pore opening, phosphorylating BAD, activating nitric oxide synthase, Pim-1 kinase, and Bcl-2, and preserving the myocardium against the caspase 3 activation.


Assuntos
Cardiotônicos/farmacologia , Miocárdio/metabolismo , Consumo de Oxigênio/efeitos dos fármacos , Consumo de Oxigênio/fisiologia , Pravastatina/farmacologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Técnicas de Cultura de Órgãos
19.
Front Immunol ; 12: 693613, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34295335

RESUMO

ß-glucans are prebiotic and/or food additives used by the aquaculture industry to enhance the immune response of fish. Their efficiency may vary according to their origin and structure. In this study, the immunostimulant effects of two ß-glucan types extracted from wild-type baker's yeast (Saccharomyces cerevisiae) and its null-mutant Gas1 were investigated. Gas1 has a beta-1,3-glucanosyltransferase activity necessary for cell wall assembly. Using a positive (commercial product MacroGard®) and a negative control (a diet without glucans), we evaluated the immune responses and disease resistance of rainbow trout juveniles (mean weight, ~44 g) fed control, low (0.2%) and high (0.5%) doses of Macrogard®, Gas1, and Wild type-ß-glucan after a short-term (15 days, D15) or mid-term (36 days, D36) feeding periods. We found that ß-glucan supplemented diets did not affect growth performance, mortality, splenic index, or leukocyte respiratory burst activity on D15 nor D36. However, each ß-glucan triggered different immune effectors, depending of the doses or length of exposure compared to others and/or the negative control. Indeed, high dose of MacroGard® significantly increased lysozyme activities at D15 compared with the control and other diets (p<0.05). At D36, MacroGard ß-glucan enhanced the production of lymphocytes in comparison with the control diet (p<0.05). Regarding WT ß-glucan, at D36, WT-ß-glucan, especially the high dose, provided the highest enzymatic activities (lysozyme and ACH50) and Ig level (p<0.01). Furthermore, on D36, Gas1 also increased lysozyme activity, Ig proportion, and some immune genes (mcsfra, hepcidin) compared with MacroGard® (p<0.05). Besides, both doses of Gas1-ß-glucans increased the resistance of juveniles to bacterial infection highlighted by a higher survival rate at 14 days post-challenge compared with the control and other types and doses of ß-glucans (p<0.05). In conclusion, our results suggest that Gas1-ß-glucan could represent a promising immunostimulant that would help to prevent diseases in aquaculture even more efficiently than other ß-glucans already in use. Mode of action and particular efficiency of this new Gas1 mutant are debated.


Assuntos
Adjuvantes Imunológicos/farmacologia , Aeromonas salmonicida/patogenicidade , Suplementos Nutricionais , Furunculose/prevenção & controle , Infecções por Bactérias Gram-Negativas/veterinária , Oncorhynchus mykiss/microbiologia , beta-Glucanas/farmacologia , Aeromonas salmonicida/imunologia , Ração Animal , Animais , Peptídeos Catiônicos Antimicrobianos/metabolismo , Pesqueiros , Furunculose/imunologia , Furunculose/microbiologia , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Negativas/prevenção & controle , Imunidade Humoral/efeitos dos fármacos , Mediadores da Inflamação/metabolismo , Leucócitos/efeitos dos fármacos , Leucócitos/imunologia , Leucócitos/metabolismo , Oncorhynchus mykiss/imunologia , Oncorhynchus mykiss/metabolismo , Fatores de Tempo
20.
Aquat Toxicol ; 231: 105676, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33341509

RESUMO

The present study aimed at investigating interactive effects between dietary lipids and both short- and long-term exposures to a low, environmentally realistic, cadmium (Cd) concentration. Juvenile rainbow trout were fed four isolipidic diets (31.7 g/kg) enriched in either linoleic acid (LA, 18:2n-6), alpha-linolenic acid (ALA, 18:3n-3), eicosapentaenoic acid (EPA, 20:5n-3) or docosahexaenoic acid (DHA, 22:6n-3). From the 4th week of this 10-week experiment, the lipid level of the diet was increased (120.0 g/kg) and half of the fish fed each diet were aqueously exposed to Cd (0.3 µg/L) while the other half were not exposed to Cd (control). Fish were sampled and their liver was harvested for fatty acid profile, hepatic Cd and calcium concentrations, total glutathione level and gene expression assessment, either (i) after 4 weeks of feeding and 24 h of Cd contamination (day 29) (short-term Cd exposure) or (ii) after 10 weeks of feeding and 6 weeks of Cd contamination (day 70) (long-term Cd exposure). We found that both dietary lipids and Cd exposure influenced fatty acid homeostasis and metabolism. The hepatic fatty acid profile mostly reflected that of the diet (e.g. n-3/n-6 ratio) with some differences, including selective retention of specific long chain polyunsaturated fatty acids (LC-PUFAs) like DHA and active biotransformation of dietary LA and ALA into LC-PUFAs. Cd effects on hepatic fatty acid profiles were influenced by the duration of the exposure and the nutritional status of the fish. The effects of diet and Cd exposure on the fatty acid profiles were only sparsely explained by variation of the expression pattern of genes involved in fatty acid metabolism. The biological responses to Cd were also influenced by dietary lipids. Fish fed the ALA-enriched diet seemed to be the least affected by the Cd exposure, as they showed a higher detoxifying ability against Cd with an early upregulation of protective metallothionein a (MTa) and apoptosis regulator BCL2-Like1 (BCLx) genes, an increased long-term phospholipid synthesis and turnover and fatty acid bioconversion efficiency, as well as a lower long-term accumulation of Cd in their liver. In contrast, fish fed the EPA-enriched diet seemed to be the most sensitive to a long-term Cd exposure, with an impaired growth performance and a decreased antioxidant capacity (lower glutathione level). Our results highlight that low, environmentally realistic aqueous concentrations of Cd can affect biological response in fish and that these effects are influenced by the dietary fatty acid composition.


Assuntos
Cádmio/toxicidade , Dieta , Exposição Ambiental , Ácidos Graxos/metabolismo , Fígado/metabolismo , Oncorhynchus mykiss/metabolismo , Estresse Fisiológico , Animais , Cálcio/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Ácidos Docosa-Hexaenoicos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Glutationa/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Oncorhynchus mykiss/genética , Oncorhynchus mykiss/crescimento & desenvolvimento , Poluentes Químicos da Água/toxicidade
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