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Sample records for adult zebrafish danio

  1. Long-term (30 days toxicity of NiO nanoparticles for adult zebrafish Danio rerio

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    Kovrižnych Jevgenij A.

    2014-03-01

    Full Text Available Nickel oxide in the form of nanoparticles (NiO NPs is extensively used in different industrial branches. In a test on adult zebrafish, the acute toxicity of NiO NPs was shown to be low, however longlasting contact with this compound can lead to its accumulation in the tissues and to increased toxicity. In this work we determined the 30-day toxicity of NiO NPs using a static test for zebrafish Danio rerio. We found the 30-day LC50 value to be 45.0 mg/L, LC100 (minimum concentration causing 100% mortality was 100.0 mg/L, and LC0 (maximum concentration causing no mortality was 6.25 mg/L for adult individuals of zebrafish. Considering a broad use of Ni in the industry, NiO NPs chronic toxicity may have a negative impact on the population of aquatic organisms and on food web dynamics in aquatic systems.

  2. Sexual dimorphisms in swimming behavior, cerebral metabolic activity and adrenoceptors in adult zebrafish (Danio rerio).

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    Ampatzis, Konstantinos; Dermon, Catherine R

    2016-10-01

    Sexually dimorphic behaviors and brain sex differences, not only restricted to reproduction, are considered to be evolutionary preserved. Specifically, anxiety related behavioral repertoire is suggested to exhibit sex-specific characteristics in rodents and primates. The present study investigated whether behavioral responses to novelty, have sex-specific characteristics in the neurogenetic model organism zebrafish (Danio rerio), lacking chromosomal sex determination. For this, aspects of anxiety-like behavior (including reduced exploration, increased freezing behavior and erratic movement) of male and female adult zebrafish were tested in a novel tank paradigm and after habituation. Male and female zebrafish showed significant differences in their swimming activity in response to novelty, with females showing less anxiety spending more time in the upper tank level. When fish have habituated, regional cerebral glucose uptake, an index of neuronal activity, and brain adrenoceptors' (ARs) expression (α2-ARs and β-ARs) were determined using in vivo 2-[(14)C]-deoxyglucose methodology and in vitro neurotransmitter receptors quantitative autoradiography, respectively. Intriguingly, females exhibited higher glucose utilization than males in hypothalamic brain areas. Adrenoceptor's expression pattern was dimorphic in zebrafish telencephalic, preoptic, hypothalamic nuclei, central gray, and cerebellum, similarly to birds and mammals. Specifically, the lateral zone of dorsal telencephalon (Dl), an area related to spatial cognition, homologous to the mammalian hippocampus, showed higher α2-AR densities in females. In contrast, male cerebellum included higher densities of β-ARs in comparison to female. Taken together, our data demonstrate a well-defined sex discriminant cerebral metabolic activity and ARs' pattern in zebrafish, possibly contributing to male-female differences in the swimming behavior. PMID:27363927

  3. Effects of butachlor on reproduction and hormone levels in adult zebrafish (Danio rerio).

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    Chang, Juhua; Liu, Shaoying; Zhou, Shengli; Wang, Minghua; Zhu, Guonian

    2013-01-01

    Butachlor, a chloracetamide herbicide, is widely used in China. In the present study, paired adult male and female zebrafish (Danio rerio) were exposed to various concentrations of butachlor (0, 25, 50 and 100 μg/L) for 30 days, and the effects on reproduction and endocrine disruption were evaluated using fecundity, condition factor (CF), gonadosomatic index (GSI), liver somatic index (LSI), plasma vitellogenin (VTG), sex steroids and thyroid hormone levels as endpoints. Our results showed that the mean fecundity rates were significantly decreased at 50 and 100 μg/L butachlor during the 30-day exposure period. At the end of the exposure period, no significant changes were observed in CF and LSI in both females and males, while GSI was significantly reduced in males at 50 and 100 μg/L butachlor. At 100 μg/L butachlor, plasma testosterone (T) and 17β-estradiol (E2) levels were significantly decreased in females, while plasma VTG level was significantly increased in males. Plasma thyroxine (T4) and triiodothyronine (T3) levels were significantly increased at 50 and 100 μg/L butachlor in males, and at 100 μg/L in females. This work demonstrated that butachlor adversely affected the normal reproductive success of zebrafish, and disrupted the thyroid and sex steroid endocrine systems, which provides the basis for the estimated ecological risk during butachlor exposure.

  4. Valerenic acid and Valeriana officinalis extracts delay onset of Pentylenetetrazole (PTZ)-Induced seizures in adult Danio rerio (Zebrafish)

    OpenAIRE

    Torres-Hernández, Bianca A.; Del Valle-Mojica, Lisa M.; Ortíz, José G.

    2015-01-01

    Background Anticonvulsant properties have been attributed to extracts of the herbal medicine Valeriana officinalis. Our aims were to examine the anticonvulsant properties of valerenic acid and valerian extracts and to determine whether valerian preparations interact with the activity of other anti-epileptic drugs (phenytoin or clonazepam). To achieve these goals, we validated the adult zebrafish, Danio rerio, as an animal model for studying anticonvulsant drugs. Methods All drug treatments we...

  5. Enantio-alteration of gene transcription associated with bioconcentration in adult zebrafish (Danio rerio) exposed to chiral PCB149

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    Chai, Tingting; Cui, Feng; Mu, Pengqian; Yang, Yang; Xu, Nana; Yin, Zhiqiang; Jia, Qi; Yang, Shuming; Qiu, Jing; Wang, Chengju

    2016-01-01

    Enantioselective enrichment of chiral PCB149 (2,2’,3,4’,5’,6-hexachlorobiphenyl) was analysed in adult zebrafish (Danio rerio) exposed to the racemate, (‑)-PCB149, and (+)-PCB149. Greater enrichment of (‑)-PCB149 compared to (+) PCB149 was observed following 0.5 ng/L exposure; however, as the exposure time and concentration increased, racemic enrichment was observed in adult fish exposed to the racemate. No biotransformation between the two isomers was observed in fish exposed to single enantiomers. When zebrafish were exposed to different forms of chiral PCB149, enantioselective expression of genes associated with polychlorinated biphenyls (PCBs) was observed in brain and liver tissues and enantioselective correlations between bioconcentration and target gene expression levels were observed in brain and liver tissues. The strong positive correlations between expression levels of target genes (alox5a and alox12) and PCB149 bioconcentration suggest that prolonged exposure to the racemate of chiral PCB149 may result in inflammation-associated diseases. Prolonged exposure to (‑)-PCB149 may also affect metabolic pathways such as dehydrogenation and methylation in the brain tissues of adult zebrafish. Hepatic expression levels of genes related to the antioxidant system were significantly negatively correlated with bioconcentration following exposure to (+)-PCB149.

  6. Ethylnitrosourea induces neoplasia in zebrafish (Danio rerio).

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    Beckwith, L G; Moore, J L; Tsao-Wu, G S; Harshbarger, J C; Cheng, K C

    2000-03-01

    The zebrafish (Danio rerio) has been successfully used to discover hundreds of genes involved in development and organogenesis. To address the potential of zebrafish as a cancer model, it is important to determine the susceptibility of zebrafish to tumors. Germ line mutations are most commonly induced for zebrafish mutant screens by exposing adult male zebrafish to the alkylating agent, ethylnitrosourea (ENU). To determine whether ENU induces tumors, we compared the incidence of tumors in ENU-treated fish with untreated controls. Interestingly, 18 of 18 (100%) fish mutagenized with either 2.5 or 3.0 mM ENU developed epidermal papillomas, which numbered 1 to 22 per fish, within 1 year of treatment. The induced epidermal lesions included epidermal hyperplasia, flat papillomas (0.2 to 1.2 mm), and pedunculated papillomas (1.2 to 8 mm in greatest dimension), but no skin cancers. Angiogenesis was evident in papillomas larger than approximately 1 mm. All but two papillomas contained the three cell types (keratinocytes, club, and mucous cells) of normal zebrafish epidermis; histologic variants lacked either club cells or mucous cells. Two cavernous hemangiomas and a single malignant peripheral nerve sheath tumor were also found in the treated fish. None of five untreated controls developed tumors. These studies establish the feasibility of the zebrafish as an experimental model for the study of skin tumors. PMID:10744073

  7. Organization of the histaminergic system in adult zebrafish (Danio rerio) brain: neuron number, location, and cotransmitters.

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    Sundvik, Maria; Panula, Pertti

    2012-12-01

    Histamine is an essential factor in the ascending arousal system (AAS) during motivated behaviors. Histamine and hypocretin/orexin (hcrt) are proposed to be responsible for different aspects of arousal and wakefulness, histamine mainly for cognitive and motivated behaviors. In this study we visualized the entire histaminergic neuron population in adult male and female zebrafish brain and quantified the histaminergic neuron numbers. There were 40-45 histaminergic neurons in both male and female zebrafish brain. Further, we identified cotransmitters of histaminergic neurons in the ventrocaudal hypothalamus, i.e., around the posterior recess (PR) in adult zebrafish. Galanin, γ-aminobutyric acid (GABA), and thyrotropin-releasing hormone (TRH) were colocalized with histamine in some but not all neurons, a result that was verified by intracerebroventricular injections of colchicine into adult zebrafish. Fibers immunoreactive (ir) for galanin, GABA, TRH, or methionine-enkephalin (mENK) were dense in the ventrocaudal hypothalamus around the histaminergic neurons. In histamine-ir fibers TRH and galanin immunoreactivities were also detected in the ventral telencephalon. All these neurotransmitters are involved in maintaining the equilibrium of the sleep-wake state. Our results are in accordance with results from rats, further supporting the use of zebrafish as a tool to study molecular mechanisms underlying complex behaviors.

  8. Copper at low levels impairs memory of adult zebrafish (Danio rerio) and affects swimming performance of larvae.

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    Acosta, Daiane da Silva; Danielle, Naissa Maria; Altenhofen, Stefani; Luzardo, Milene Dornelles; Costa, Patrícia Gomes; Bianchini, Adalto; Bonan, Carla Denise; da Silva, Rosane Souza; Dafre, Alcir Luiz

    2016-01-01

    Metal contamination at low levels is an important issue because it usually produces health and environmental effects, either positive or deleterious. Contamination of surface waters with copper (Cu) is a worldwide event, usually originated by mining, agricultural, industrial, commercial, and residential activities. Water quality criteria for Cu are variable among countries but allowed limits are generally in the μg/L range, which can disrupt several functions in the early life-stages of fish species. Behavioral and biochemical alterations after Cu exposure have also been described at concentrations close to the allowed limits. Aiming to search for the effects of Cu in the range of the allowed limits, larvae and adult zebrafish (Danio rerio) were exposed to different concentrations of dissolved Cu (nominally: 0, 5, 9, 20 and 60μg/L; measured: 0.4, 5.7, 7.2 16.6 and 42.3μg/L, respectively) for 96h. Larvae swimming and body length, and adult behavior and biochemical biomarkers (activity of glutathione-related enzymes in gills, muscle, and brain) were assessed after Cu exposure. Several effects were observed in fish exposed to 9μg/L nominal Cu, including increased larvae swimming distance and velocity, abolishment of adult inhibitory avoidance memory, and decreased glutathione S-transferase (GST) activity in gills of adult fish. At the highest Cu concentration tested (nominally: 60μg/L), body length of larvae, spatial memory of adults, and gill GST activity were decreased. Social behavior (aggressiveness and conspecific interaction), and glutathione reductase (GR) activity were not affected in adult zebrafish. Exposure to Cu, at concentrations close to the water quality criteria for this metal in fresh water, was able to alter larvae swimming performance and to induce detrimental effects on the behavior of adult zebrafish, thus indicating the need for further studies to reevaluate the currently allowed limits for Cu in fresh water. PMID:27012768

  9. Global DNA methylation in gonads of adult zebrafish Danio rerio under bisphenol A exposure.

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    Liu, Yan; Zhang, Yingying; Tao, Shiyu; Guan, Yongjing; Zhang, Ting; Wang, Zaizhao

    2016-08-01

    Altered DNA methylation is pervasively associated with changes in gene expression and signal transduction after exposure to a wide range of endocrine disrupting chemicals. As a weak estrogenic chemical, bisphenol A (BPA) has been extensively studied for reproductive toxicity. In order to explore the effects of BPA on epigenetic modification in gonads of zebrafish Danio rerio, we measured the global DNA methylation together with the gene expression of DNA methyltransferase (dnmts), glycine N-methyltransferase (gnmt), and ten-eleven translocation (tets) in gonads of D. rerio under BPA exposure by ELISA and quantitative real-time PCR method, respectively. The global level of DNA methylation was significantly decreased in ovaries after exposed to BPA for 7 days, and testes following 35-day exposure. Moreover, the global level of DNA methylation was also significantly reduced in testes after exposed to 15μg/L BPA for 7 days. Besides the alteration of the global level of DNA methylation, varying degrees of transcriptional changes of dnmts, gnmt and tets were detected in gonads of D. rerio under BPA exposure. The present study suggested that BPA might cause the global DNA demethylation in gonads of zebrafish by regulating the transcriptional changes of the DNA methylation/demethylation-associated genes (dnmts, gnmt, and tets). PMID:27101439

  10. Manipulating galectin expression in zebrafish (Danio rerio)

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    Feng, C.; Nita-Lazar, M.; Gonzalez-Montalban, N.; Wang, J.; Mancini, J.; Ravindran, C.; Ahmed, H.; Vasta, G.R.

    Techniques for disrupting gene expression are invaluable tools for the analysis of the biological role(s) of a gene product. Because of its genetic tractability and multiple advantages over conventional mammalian models, the zebrafish (Danio rerio...

  11. The Behavioral Effects of Single Housing and Environmental Enrichment on Adult Zebrafish (Danio rerio).

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    Collymore, Chereen; Tolwani, Ravi J; Rasmussen, Skye

    2015-05-01

    Environmental enrichment provides laboratory-housed species the opportunity to express natural behavior and exert control over their home environment, thereby minimizing stress. We sought to determine whether providing an artificial plant in the holding tank as enrichment influenced anxiety-like behaviors and place-preference choice in adult zebrafish. Fish were housed singly or in social groups of 5 for 3 wk in 1 of 4 experimental housing environments: single-housed enriched (n = 30), single-housed barren (n = 30), group-housed enriched (n = 30), and group-housed barren (n = 30). On week 4, individual fish were selected randomly from each of the experimental housing environments and tested by using novel-tank, light-dark, and place-preference tests. Housing fish singly in a barren environment increased anxiety-like behaviors in the novel-tank and light-dark behavioral tests. Single-housed zebrafish in barren tanks as well as zebrafish group-housed with conspecifics, both with and without plant enrichment, spent more time associating with conspecifics than with the artificial plant enrichment device during the place-preference test. Single-housed fish maintained in enriched tanks displayed no preference between a compartment with conspecifics or an artificial plant. Our results suggest the addition of an artificial plant as enrichment may benefit single-housed zebrafish when social housing is not possible.

  12. Exercise quantity-dependent muscle hypertrophy in adult zebrafish (Danio rerio).

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    Hasumura, Takahiro; Meguro, Shinichi

    2016-07-01

    Exercise is very important for maintaining and increasing skeletal muscle mass, and is particularly important to prevent and care for sarcopenia and muscle disuse atrophy. However, the dose-response relationship between exercise quantity, duration/day, and overall duration and muscle mass is poorly understood. Therefore, we investigated the effect of exercise duration on skeletal muscle to reveal the relationship between exercise quantity and muscle hypertrophy in zebrafish forced to exercise. Adult male zebrafish were exercised 6 h/day for 4 weeks, 6 h/day for 2 weeks, or 3 h/day for 2 weeks. Flow velocity was adjusted to maximum velocity during continual swimming (initial 43 cm/s). High-speed consecutive photographs revealed that zebrafish mainly drove the caudal part. Additionally, X-ray micro computed tomography measurements indicated muscle hypertrophy of the mid-caudal half compared with the mid-cranial half part. The cross-sectional analysis of the mid-caudal half muscle revealed that skeletal muscle (red, white, or total) mass increased with increasing exercise quantity, whereas that of white muscle and total muscle increased only under the maximum exercise load condition of 6 h/day for 4 weeks. Additionally, the muscle fiver size distributions of exercised fish were larger than those from non-exercised fish. We revealed that exercise quantity, duration/day, and overall duration were correlated with skeletal muscle hypertrophy. The forced exercise model enabled us to investigate the relationship between exercise quantity and skeletal muscle mass. These results open up the possibility for further investigations on the effects of exercise on skeletal muscle in adult zebrafish. PMID:26951149

  13. Acute Exposure to Microcystin-Producing Cyanobacterium Microcystis aeruginosa Alters Adult Zebrafish (Danio rerio Swimming Performance Parameters

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    Luiza Wilges Kist

    2011-01-01

    Full Text Available Microcystins (MCs are toxins produced by cyanobacteria (blue-green algae, primarily Microcystis aeruginosa, forming water blooms worldwide. When an organism is exposed to environmental perturbations, alterations in normal behavioral patterns occur. Behavioral repertoire represents the consequence of a diversity of physiological and biochemical alterations. In this study, we assessed behavioral patterns and whole-body cortisol levels of adult zebrafish (Danio rerio exposed to cell culture of the microcystin-producing cyanobacterium M. aeruginosa (MC-LR, strain RST9501. MC-LR exposure (100 μg/L decreased by 63% the distance traveled and increased threefold the immobility time when compared to the control group. Interestingly, no significant alterations in the number of line crossings were found at the same MC-LR concentration and time of exposure. When animals were exposed to 50 and 100 μg/L, MC-LR promoted a significant increase (around 93% in the time spent in the bottom portion of the tank, suggesting an anxiogenic effect. The results also showed that none of the MC-LR concentrations tested promoted significant alterations in absolute turn angle, path efficiency, social behavior, or whole-body cortisol level. These findings indicate that behavior is susceptible to MC-LR exposure and provide evidence for a better understanding of the ecological consequences of toxic algal blooms.

  14. Acute Exposure to Microcystin-Producing Cyanobacterium Microcystis aeruginosa Alters Adult Zebrafish (Danio rerio) Swimming Performance Parameters.

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    Kist, Luiza Wilges; Piato, Angelo Luis; da Rosa, João Gabriel Santos; Koakoski, Gessi; Barcellos, Leonardo José Gil; Yunes, João Sarkis; Bonan, Carla Denise; Bogo, Maurício Reis

    2011-01-01

    Microcystins (MCs) are toxins produced by cyanobacteria (blue-green algae), primarily Microcystis aeruginosa, forming water blooms worldwide. When an organism is exposed to environmental perturbations, alterations in normal behavioral patterns occur. Behavioral repertoire represents the consequence of a diversity of physiological and biochemical alterations. In this study, we assessed behavioral patterns and whole-body cortisol levels of adult zebrafish (Danio rerio) exposed to cell culture of the microcystin-producing cyanobacterium M. aeruginosa (MC-LR, strain RST9501). MC-LR exposure (100 μg/L) decreased by 63% the distance traveled and increased threefold the immobility time when compared to the control group. Interestingly, no significant alterations in the number of line crossings were found at the same MC-LR concentration and time of exposure. When animals were exposed to 50 and 100 μg/L, MC-LR promoted a significant increase (around 93%) in the time spent in the bottom portion of the tank, suggesting an anxiogenic effect. The results also showed that none of the MC-LR concentrations tested promoted significant alterations in absolute turn angle, path efficiency, social behavior, or whole-body cortisol level. These findings indicate that behavior is susceptible to MC-LR exposure and provide evidence for a better understanding of the ecological consequences of toxic algal blooms. PMID:22253623

  15. Feed and feeding regime affect growth rate and gonadosomatic index of adult zebrafish (Danio rerio).

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    Gonzales, John M; Law, Sheran Hiu Wan

    2013-12-01

    A 5-week study was conducted to evaluate commercially available Artemia, Ziegler zebrafish diet, and Calamac diet fed in five different feeding regimes on the growth and reproductive development of 7-month-old zebrafish. Zebrafish were fed to satiation three times daily during the normal work week and twice daily during the weekend and holidays. Zebrafish in dietary groups CCC (Calamac three times daily) and CCA (Calamac twice daily, Artemia once daily) had a significantly (p<0.05) greater weight gain and specific growth rate as compared to all other dietary groups. Male zebrafish in dietary group 5 had significantly larger gonadosomatic index (GSI) values than all other groups, while female zebrafish in dietary group CCC had significantly larger GSI values than all other groups. No differences in the fatty acid content of female gonads were detected. Zebrafish fed solely Artemia had the greatest weight loss and lowest GSI values. Preliminary evidence of protein sparing in zebrafish is reported. Collectively, this study sheds more light into the effects of the use of commercially available feeds and feeding regime on the rearing of zebrafish. PMID:23902461

  16. Neurotoxicity of neem commercial formulation (Azadirachta indica A. Juss) in adult zebrafish (Danio rerio).

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    Bernardi, M M; Dias, S G; Barbosa, V E

    2013-11-01

    The neurotoxic effects of a commercial formulation of Azadirachta indica A. Juss, also called neem or nim, in adult zebrafish were determined using behavioral models. General activity, anxiety-like effects, and learning and memory in a passive avoidance task were assessed after exposure to 20 or 40 μl/L neem. The results showed that 20 μl/L neem reduced the number of runs. Both neem concentrations increased the number of climbs to the water surface, and 40 μl/L increased the number of tremors. In the anxiety test, the 20 μl/L dose increased the number of entries in the light side compared with controls, but the latency to enter the dark side and the freezing behavior in this side did not changed. In relation to controls, the 40 μl/L neem reduced the latency to enter in the light side, did not change the number of entries in this side and increased freezing behavior in the light side. In the passive avoidance test, pre-training and pre-test neem exposure to 40 μl/L decreased the response to the learning task. Thus, no impairment was observed in this behavioral test. We conclude that neem reduced general activity and increased anxiety-like behavior but did not affect learning and memory.

  17. Inhibition of phosphorylated tyrosine hydroxylase attenuates ethanol-induced hyperactivity in adult zebrafish (Danio rerio).

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    Nowicki, Magda; Tran, Steven; Chatterjee, Diptendu; Gerlai, Robert

    2015-11-01

    Zebrafish have been successfully employed in the study of the behavioural and biological effects of ethanol. Like in mammals, low to moderate doses of ethanol induce motor hyperactivity in zebrafish, an effect that has been attributed to the activation of the dopaminergic system. Acute ethanol exposure increases dopamine (DA) in the zebrafish brain, and it has been suggested that tyrosine hydroxylase, the rate-limiting enzyme of DA synthesis, may be activated in response to ethanol via phosphorylation. The current study employed tetrahydropapaveroline (THP), a selective inhibitor of phosphorylated tyrosine hydroxylase, for the first time, in zebrafish. We treated zebrafish with a THP dose that did not alter baseline motor responses to examine whether it can attenuate or abolish the effects of acute exposure to alcohol (ethanol) on motor activity, on levels of DA, and on levels of dopamine's metabolite 3,4-dihydroxyphenylacetic acid (DOPAC). We found that 60-minute exposure to 1% alcohol induced motor hyperactivity and an increase in brain DA. Both of these effects were attenuated by pre-treatment with THP. However, no differences in DOPAC levels were found among the treatment groups. These findings suggest that tyrosine hydroxylase is activated via phosphorylation to increase DA synthesis during alcohol exposure in zebrafish, and this partially mediates alcohol's locomotor stimulant effects. Future studies will investigate other potential candidates in the molecular pathway to further decipher the neurobiological mechanism that underlies the stimulatory properties of this popular psychoactive drug.

  18. Husbandry of zebrafish, Danio rerio, and the cortisol stress response.

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    Pavlidis, Michail; Digka, Nikoletta; Theodoridi, Antonia; Campo, Aurora; Barsakis, Konstantinos; Skouradakis, Gregoris; Samaras, Athanasios; Tsalafouta, Alexandra

    2013-12-01

    The effect of common husbandry conditions (crowding, social environment, water quality, handling, and background color) on the cortisol stress response in adult zebrafish, Danio rerio, was investigated to check the usefulness of zebrafish as a model organism in aquaculture research. In addition, a noninvasive methodology for assessing stress was evaluated. Zebrafish showed a fast cortisol response with high values at 30 min that returned to basal levels within 2 h of poststress. There was a significant positive correlation between trunk cortisol concentrations and the free water cortisol rate (r(2)=0.829-0.850, pzebrafish. It is concluded that adult laboratory zebrafish had a preference for a transparent or black background aquarium, at a number of 10 individuals per 2 L of available water volume, to express their normal behavior and avoid increased cortisol stress reaction.

  19. A New Anaesthetic Protocol for Adult Zebrafish (Danio rerio: Propofol Combined with Lidocaine.

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    Ana M Valentim

    Full Text Available The increasing use of zebrafish model has not been accompanied by the evolution of proper anaesthesia for this species in research. The most used anaesthetic in fishes, MS222, may induce aversion, reduction of heart rate, and consequently high mortality, especially during long exposures. Therefore, we aim to explore new anaesthetic protocols to be used in zebrafish by studying the quality of anaesthesia and recovery induced by different concentrations of propofol alone and in combination with different concentrations of lidocaine.In experiment A, eighty-three AB zebrafish were randomly assigned to 7 different groups: control, 2.5 (2.5P, 5 (5P or 7.5 μg/ml (7.5P of propofol; and 2.5 μg/ml of propofol combined with 50, (P/50L, 100 (P/100L or 150 μg/ml (P/150L of lidocaine. Zebrafish were placed in an anaesthetic water bath and time to lose the equilibrium, reflex to touch, reflex to a tail pinch, and respiratory rate were measured. Time to gain equilibrium was also assessed in a clean tank. Five and 24 hours after anaesthesia recovery, zebrafish were evaluated concerning activity and reactivity. Afterwards, in a second phase of experiments (experiment B, the best protocol of the experiment A was compared with a new group of 8 fishes treated with 100 mg/L of MS222 (100M.In experiment A, only different concentrations of propofol/lidocaine combination induced full anaesthesia in all animals. Thus only these groups were compared with a standard dose of MS222 in experiment B. Propofol/lidocaine induced a quicker loss of equilibrium, and loss of response to light and painful stimuli compared with MS222. However zebrafish treated with MS222 recovered quickly than the ones treated with propofol/lidocaine.In conclusion, propofol/lidocaine combination and MS222 have advantages in different situations. MS222 is ideal for minor procedures when a quick recovery is important, while propofol/lidocaine is best to induce a quick and complete anaesthesia.

  20. Endosulfan affects health variables in adult zebrafish (Danio rerio) and induces alterations in larvae development

    DEFF Research Database (Denmark)

    Velasco-Santamaria, Y. M.; Handy, R. D.; Sloman, K. A.

    2011-01-01

    to controls. Both concentrations of endosulfan caused a 4.0 fold increase in Na(+)K(+)-ATPase activity compared to controls (ANOVA, p ANOVA, p ... alterations in the progeny of fish exposed to endosulfan were observed. Heart beat frequency was significantly lower in larvae from exposed adults to 0.16 mu g/L compared to the control (ANOVA, p

  1. Characterization of snakehead rhabdovirus infection in zebrafish (Danio rerio).

    Science.gov (United States)

    Phelan, Peter E; Pressley, Meagan E; Witten, P Eckhard; Mellon, Mark T; Blake, Sharon; Kim, Carol H

    2005-02-01

    The zebrafish, Danio rerio, has become recognized as a valuable model for the study of development, genetics, and toxicology. Recently, the zebrafish has been recognized as a useful model for infectious disease and immunity. In this study, the pathogenesis and antiviral immune response of zebrafish to experimental snakehead rhabdovirus (SHRV) infection was characterized. Zebrafish 24 h postfertilization to 30 days postfertilization were susceptible to infection by immersion in 10(6) 50% tissue culture infective doses (TCID50) of SHRV/ml, and adult zebrafish were susceptible to infection by intraperitoneal (i.p.) injection of 10(5) TCID50 of SHRV/ml. Mortalities exceeded 40% in infected fish, and clinical presentation of infection included petechial hemorrhaging, redness of the abdomen, and erratic swim behavior. Virus reisolation and reverse transcription-PCR analysis of the viral nucleocapsid gene confirmed the presence of SHRV. Histological sections of moribund embryonic and juvenile fish revealed necrosis of the pharyngeal epithelium and liver, in addition to congestion of the swim bladder by cell debris. Histopathology in adult fish injected i.p. was confined to the site of injection. The antiviral response in zebrafish was monitored by quantitative real-time PCR analysis of zebrafish interferon (IFN) and Mx expression. IFN and Mx levels were elevated in zebrafish exposed to SHRV, although expression and intensity differed with age and route of infection. This study is the first to examine the pathogenesis of SHRV infection in zebrafish. Furthermore, this study is the first to describe experimental infection of zebrafish embryos with a viral pathogen, which will be important for future experiments involving targeted gene disruption and forward genetic screens.

  2. Long-term exposure to paraquat alters behavioral parameters and dopamine levels in adult zebrafish (Danio rerio).

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    Bortolotto, Josiane W; Cognato, Giana P; Christoff, Raissa R; Roesler, Laura N; Leite, Carlos E; Kist, Luiza W; Bogo, Mauricio R; Vianna, Monica R; Bonan, Carla D

    2014-04-01

    Chronic exposure to paraquat (Pq), a toxic herbicide, can result in Parkinsonian symptoms. This study evaluated the effect of the systemic administration of Pq on locomotion, learning and memory, social interaction, tyrosine hydroxylase (TH) expression, dopamine and 3,4-dihydroxyphenylacetic acid (DOPAC) levels, and dopamine transporter (DAT) gene expression in zebrafish. Adult zebrafish received an i.p. injection of either 10 mg/kg (Pq10) or 20 mg/kg (Pq20) of Pq every 3 days for a total of six injections. Locomotion and distance traveled decreased at 24 h after each injection in both treatment doses. In addition, both Pq10- and Pq20-treated animals exhibited differential effects on the absolute turn angle. Nonmotor behaviors were also evaluated, and no changes were observed in anxiety-related behaviors or social interactions in Pq-treated zebrafish. However, Pq-treated animals demonstrated impaired acquisition and consolidation of spatial memory in the Y-maze task. Interestingly, dopamine levels increased while DOPAC levels decreased in the zebrafish brain after both treatments. However, DAT expression decreased in the Pq10-treated group, and there was no change in the Pq20-treated group. The amount of TH protein showed no significant difference in the treated group. Our study establishes a new model to study Parkinson-associated symptoms in zebrafish that have been chronically treated with Pq.

  3. Visual discrimination learning in zebrafish (Danio rerio).

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    Colwill, Ruth M; Raymond, Maria P; Ferreira, Lisa; Escudero, Holly

    2005-08-31

    Three experiments demonstrated visual discrimination learning in zebrafish (Danio rerio). In each experiment, zebrafish were given a choice between two visually distinct arms of a T-maze. Choice of one stimulus was always followed by a food reward, but choice of the other stimulus was not rewarded. Different colored sleeves fitted around the arms of the T-maze were used in Experiments 1 (green and purple) and 2 (red and blue). The stimuli used in Experiment 3 were white sleeves lined with horizontal or vertical black stripes. In all three experiments, zebrafish acquired a significant preference for the stimulus that led to a food reward. Experiments 1 and 2 also showed that zebrafish could learn a reversal of the discrimination. Finally, the effect of discontinuing food rewards was examined after reversal training in Experiment 2 and after initial discrimination training in Experiments 1 and 3. Non-reinforcement led to a decrease in correct responding in Experiments 2 and 3 independent of stimulus identity, but to an asymmetrical pattern of responding in Experiment 1. The median latency to make a choice response decreased over the course of acquisition in all three experiments; during extinction, median response times did not change at all in Experiment 1 and increased only very slightly in Experiment 2, but showed a substantial increase in Experiment 3. The implications of these results for the zebrafish as a model system for genetic studies of learning and memory are discussed. PMID:15967284

  4. Microcystin-LR acute exposure does not alter in vitro and in vivo ATP, ADP and AMP hydrolysis in adult zebrafish (Danio rerio brain membranes

    Directory of Open Access Journals (Sweden)

    Luiza Wilges Kist

    2012-10-01

    Full Text Available Microcystins (MCs are toxins produced by cyanobacteria during the blooms that could accumulate in aquatic animals and be relocated to higher trophic levels. Adenosine triphosphate (ATP acts as an excitatory neurotransmitter and/or a neuromodulator in the extracellular space playing important roles in physiological and pathological conditions. The aim of this study was, therefore, to evaluate the acute effects of different concentrations of MC-LR on nucleoside triphosphate diphosphohydrolases and 5’-nucleotidade in adult zebrafish (Danio rerio brain membranes. The results have shown no significant changes in ATP, adenosine diphosphate (ADP and adenosine monophosphate (AMP hydrolysis in zebrafish brain membranes. MC-LR in vitro also did not alter ATP, ADP and AMP hydrolysis in the concentrations tested. These findings show that acute exposure to MC-LR did not modulate ectonucleotidase activity in the conditions tested. However, additional studies including chronic exposure should be performed in order to achieve a better understanding about MC-LR toxicity mechanisms in the central nervous system.

  5. Toxicity of tetrabromobisphenol A (TBBPA) in zebrafish (Danio rerio) in a partial life-cycle test

    NARCIS (Netherlands)

    Kuiper, R.V.; Brandhof, Van den E.J.; Leonards, P.E.G.; Ven, van der L.T.M.; Wester, P.W.; Vos, J.G.

    2007-01-01

    Toxicological effects of the widely used flame retardant, tetrabromobisphenol A (TBBPA) were assessed in a partial life-cycle test with zebrafish (Danio rerio). Exposure of adult fish during 30 days to water-borne TBBPA in nominal concentrations ranging from 0 (control) to 1.5 ¿M was followed by exp

  6. Toxicity of tetrabromobisphenol A (TBBPA) in zebrafish (Danio rerio) in a partial life-cycle test.

    NARCIS (Netherlands)

    Kuiper, R V; Brandhof, E J van den; Leonards, P E G; Ven, L T M van der; Wester, P W; Vos, J G

    2006-01-01

    Toxicological effects of the widely used flame retardant, tetrabromobisphenol A (TBBPA) were assessed in a partial life-cycle test with zebrafish (Danio rerio). Exposure of adult fish during 30 days to water-borne TBBPA in nominal concentrations ranging from 0 (control) to 1.5 muM was followed by ex

  7. Short-term exposure to low concentrations of the synthetic androgen methyltestosterone affects vitellogenin and steroid levels in adult male zebrafish (Danio rerio).

    Science.gov (United States)

    Andersen, Lene; Goto-Kazeto, Rie; Trant, John M; Nash, Jon P; Korsgaard, Bodil; Bjerregaard, Poul

    2006-03-10

    Short-term effects of methyltestosterone (MT) on the endocrine system of adult male zebrafish (Danio rerio) were examined. Males were exposed to 0, 4.5, 6.6, 8.5, 19.8, 35.9, 62.3 ng MT/l and ethinylestradiol (EE2) (26.4 ng/l) for 7 days. Several physiological endpoints that may be affected by endocrine disrupters were analysed, specifically vitellogenin (VTG) concentration, estradiol (E2), testosterone (T), and 11-ketotestosterone (KT) content, brain aromatase activity and gene expression of CYP19A1 and CYP19A2 in the testis. Exposure to the lowest MT concentration (4.5 ng MT/l), and the EE2 increased the concentration of VTG significantly compared to solvent control group. Exposure to higher concentrations of MT did not increase VTG levels. Endogenous KT and T levels decreased significantly in a concentration-dependent manner in response to the MT exposure and the lowest effective concentrations were 6.4 and 8.5 ng MT/l, respectively. The levels of KT and T were also significantly suppressed by EE2 when compared to the solvent control group. Significant decreases in endogenous E2 levels were found in some MT groups but it was not possible to distinguish a simple concentration-response relationship. No effects of MT or EE2 on the brain aromatase activity or on testicular gene expression of CYP19A1 and CYP19A2 were detected. The results show that androgens such as MT can act as endocrine disrupters even at very low concentrations.

  8. Functional Assessment of Cardiac Responses of Adult Zebrafish (Danio rerio to Acute and Chronic Temperature Change Using High-Resolution Echocardiography.

    Directory of Open Access Journals (Sweden)

    Ling Lee

    Full Text Available The zebrafish (Danio rerio is an important organism as a model for understanding vertebrate cardiovascular development. However, little is known about adult ZF cardiac function and how contractile function changes to cope with fluctuations in ambient temperature. The goals of this study were to: 1 determine if high resolution echocardiography (HRE in the presence of reduced cardiodepressant anesthetics could be used to accurately investigate the structural and functional properties of the ZF heart and 2 if the effect of ambient temperature changes both acutely and chronically could be determined non-invasively using HRE in vivo. Heart rate (HR appears to be the critical factor in modifying cardiac output (CO with ambient temperature fluctuation as it increases from 78 ± 5.9 bpm at 18°C to 162 ± 9.7 bpm at 28°C regardless of acclimation state (cold acclimated CA- 18°C; warm acclimated WA- 28°C. Stroke volume (SV is highest when the ambient temperature matches the acclimation temperature, though this difference did not constitute a significant effect (CA 1.17 ± 0.15 μL at 18°C vs 1.06 ± 0.14 μl at 28°C; WA 1.10 ± 0.13 μL at 18°C vs 1.12 ± 0.12 μl at 28°C. The isovolumetric contraction time (IVCT was significantly shorter in CA fish at 18°C. The CA group showed improved systolic function at 18°C in comparison to the WA group with significant increases in both ejection fraction and fractional shortening and decreases in IVCT. The decreased early peak (E velocity and early peak velocity / atrial peak velocity (E/A ratio in the CA group are likely associated with increased reliance on atrial contraction for ventricular filling.

  9. Effects of Pro-Tex on zebrafish (Danio rerio) larvae, adult common carp (Cyprinus carpio) and adult yellowtail kingfish (Seriola lalandi).

    Science.gov (United States)

    Boerrigter, Jeroen G J; van de Vis, Hans W; van den Bos, Ruud; Abbink, Wout; Spanings, Tom; Zethof, Jan; Martinez, Laura Louzao; van Andel, Wouter F M; Lopez-Luna, Javier; Flik, Gert

    2014-08-01

    Aquaculture practices bring several stressful events to fish. Stressors not only activate the hypothalamus-pituitary-interrenal-axis, but also evoke cellular stress responses. Up-regulation of heat shock proteins (HSPs) is among the best studied mechanisms of the cellular stress response. An extract of the prickly pear cactus (Opuntia ficus indica), Pro-Tex, a soluble variant of TEX-OE(®), may induce expression of HSPs and reduce negative effects of cellular stress. Pro-Tex therefore is used to ameliorate conditions during stressful aquaculture-related practices. We tested Pro-Tex in zebrafish (Danio rerio), common carp (Cyprinus carpio L.) and yellowtail kingfish (Seriola lalandi) exposed to aquaculture-relevant stressors (thermal stress, net confinement, transport) and assessed its effects on stress physiology. Heat shock produced a mild increase in hsp70 mRNA expression in 5-day-old zebrafish larvae. Pro-Tex increased basal hsp70 mRNA expression, but decreased heat-shock-induced expression of hsp70 mRNA. In carp, Pro-Tex increased plasma cortisol and glucose levels, while it did not affect the mild stress response (increased plasma cortisol and glucose) to net confinement. In gills, and proximal and distal intestine, stress increased hsp70 mRNA expression; in the distal intestine, an additive enhancement of hsp70 mRNA expression by Pro-Tex was seen under stress. In yellowtail kingfish, Pro-Tex reduced the negative physiological effects of transport more efficiently than when fish were sedated with AQUI-S(®). Overall, our data indicate that Pro-Tex has protective effects under high levels of stress only. As Pro-Tex has potential for use in aquaculture, its functioning and impact on health and welfare of fish should be further studied. PMID:24493298

  10. Characterization of glutathione-S-transferases in zebrafish (Danio rerio).

    Science.gov (United States)

    Glisic, Branka; Mihaljevic, Ivan; Popovic, Marta; Zaja, Roko; Loncar, Jovica; Fent, Karl; Kovacevic, Radmila; Smital, Tvrtko

    2015-01-01

    Glutathione-S-transferases (GSTs) are one of the key enzymes that mediate phase II of cellular detoxification. The aim of our study was a comprehensive characterization of GSTs in zebrafish (Danio rerio) as an important vertebrate model species frequently used in environmental research. A detailed phylogenetic analysis of GST superfamily revealed 27 zebrafish gst genes. Further insights into the orthology relationships between human and zebrafish GSTs/Gsts were obtained by the conserved synteny analysis. Expression of gst genes in six tissues (liver, kidney, gills, intestine, brain and gonads) of adult male and female zebrafish was determined using qRT-PCR. Functional characterization was performed on 9 cytosolic Gst enzymes after overexpression in E. coli and subsequent protein purification. Enzyme kinetics was measured for GSH and a series of model substrates. Our data revealed ubiquitously high expression of gstp, gstm (except in liver), gstr1, mgst3a and mgst3b, high expression of gsto2 in gills and ovaries, gsta in intestine and testes, gstt1a in liver, and gstz1 in liver, kidney and brain. All zebrafish Gsts catalyzed the conjugation of GSH to model GST substrates 1-chloro-2,4-dinitrobenzene (CDNB) and monochlorobimane (MCB), apart from Gsto2 and Gstz1 that catalyzed GSH conjugation to dehydroascorbate (DHA) and dichloroacetic acid (DCA), respectively. Affinity toward CDNB varied from 0.28 mM (Gstp2) to 3.69 mM (Gstm3), while affinity toward MCB was in the range of 5 μM (Gstt1a) to 250 μM (Gstp1). Affinity toward GSH varied from 0.27 mM (Gstz1) to 4.45 mM (Gstt1a). Turnover number for CDNB varied from 5.25s(-1) (Gstt1a) to 112s(-1) (Gstp2). Only Gst Pi enzymes utilized ethacrynic acid (ETA). We suggest that Gstp1, Gstp2, Gstt1a, Gstz1, Gstr1, Mgst3a and Mgst3b have important role in the biotransformation of xenobiotics, while Gst Alpha, Mu, Pi, Zeta and Rho classes are involved in the crucial physiological processes. In summary, this study provides the

  11. Daily variation in the shoaling behavior of zebrafish Danio rerio

    Institute of Scientific and Technical Information of China (English)

    Timothy PACIOREK; Scott MCROBERT

    2012-01-01

    Shoaling behavior provides numerous fitness benefits for fish,including enhanced access to mates,increased success in foraging and protection from predators.We were interested in determining whether shoaling intensity differed throughout the day.To do this we kept adult zebrafish Danio rerio in different lighting conditions for 10 days:“Normal” (12:12LD,lights on at 0800 hrs),“Reverse” (12:12LD,lights on at 2000 hrs),DD,or LL,and then observed the shoaling behavior at different times during the day.Our findings suggest that daily variations exist in shoaling behavior,with mean shoaling times for fish from the ‘normal' group being the lowest at the mid-point of the dark phase in the fish's subjective day (00:00 hrs),then rising significantly throughout the day,reaching their highest intensity at 20:00 lrs (lights out).Fish from the “reverse” LD cycle (lights on at 20:00 hrs) showed differences in the mean shoaling times at different times of day,but did not show a gradual increase in shoaling throughout their subjective day.Fish from the DD and LL groups did not show significant differences in the mean shoaling values at different times of day,suggesting that the differences observed in LD fish may not represent circadian rhythms.Therefore,these results demonstrate the existence of daily variations in the shoaling behavior of fish and suggest that environmental cues in the form of light/dark cycles play an important role in regulating these variations [Current Zoology 58 (1):129-137,2012].

  12. Intraperitoneal Exposure to Nano/Microparticles of Fullerene (C60) Increases Acetylcholinesterase Activity and Lipid Peroxidation in Adult Zebrafish (Danio rerio) Brain

    Science.gov (United States)

    Dal Forno, Gonzalo Ogliari; Kist, Luiza Wilges; de Azevedo, Mariana Barbieri; Fritsch, Rachel Seemann; Pereira, Talita Carneiro Brandão; Britto, Roberta Socoowski; Guterres, Sílvia Stanisçuaski; Külkamp-Guerreiro, Irene Clemes; Bonan, Carla Denise; Monserrat, José María; Bogo, Maurício Reis

    2013-01-01

    Even though technologies involving nano/microparticles have great potential, it is crucial to determine possible toxicity of these technological products before extensive use. Fullerenes C60 are nanomaterials with unique physicochemical and biological properties that are important for the development of many technological applications. The aim of this study was to evaluate the consequences of nonphotoexcited fullerene C60 exposure in brain acetylcholinesterase expression and activity, antioxidant responses, and oxidative damage using adult zebrafish as an animal model. None of the doses tested (7.5, 15, and 30 mg/kg) altered AChE activity, antioxidant responses, and oxidative damage when zebrafish were exposed to nonphotoexcited C60 nano/microparticles during 6 and 12 hours. However, adult zebrafish exposed to the 30 mg/kg dose for 24 hours have shown enhanced AChE activity and augmented lipid peroxidation (TBARS assays) in brain. In addition, the up-regulation of brain AChE activity was neither related to the transcriptional control (RT-qPCR analysis) nor to the direct action of nonphotoexcited C60 nano/microparticles on the protein (in vitro results) but probably involved a posttranscriptional or posttranslational modulation of this enzymatic activity. Taken together these findings provided further evidence of toxic effects on brain after C60 exposure. PMID:23865059

  13. Natural history of zebrafish (Danio rerio) in India.

    Science.gov (United States)

    Arunachalam, Muthukumarasamy; Raja, Manickam; Vijayakumar, Chinnian; Malaiammal, Punniyam; Mayden, Richard L

    2013-03-01

    The Zebrafish, Danio rerio, is a well-known vertebrate model species widely used in research associated with biomedical areas and comparative and evolutionary biology. Interestingly, despite the importance of this species, little is known about the natural history, habitats, and native distribution. In our study of the species, we collected individuals from twenty-one wild populations from within the species' natural distribution, ranging from streams/rivers of the Western Ghats of Peninsular India to those of the Western and North-Eastern Himalayas. Habitat types are identified from various geographic locations. Danio rerio is largely confined to and most frequently associated with habitats of low flow and with a sandy substrate in secondary and tertiary channels connected with the main channel of a stream/river, or habitats adjacent to wetlands and paddy fields. These connections can be natural channels or man-made irrigation canals, beels, or culture ponds. Among the 21 populations, individuals from two populations (one from Orissa and another from Arunachal Pradesh) were much larger in size (total length) when compared to other populations. The general habitats of Danio rerio vary from small to large mountainous and lowland streams/rivers, wetlands, and paddy fields. PMID:23590398

  14. Digestive enzymatic activity during ontogenetic development in zebrafish (Danio rerio).

    Science.gov (United States)

    Guerrera, Maria Cristina; De Pasquale, Francesca; Muglia, Ugo; Caruso, Gabriella

    2015-12-01

    Despite the growing importance of zebrafish (Danio rerio) as an experimental model in biomedical research, some aspect of physiological and related morphological age dependent changes in digestive system during larval development are still unknown. In this paper, a biochemical and morphological study of the digestive tract of zebrafish was undertaken to record the functional changes occurring in this species during its ontogenetic development, particularly from 24 hr to 47 days post fertilization (dpf). Endo- and exo-proteases, as well as α-amylase enzymes, were quantified in zebrafish larvae before first feeding (7 dpf). The most morphologically significant events during the ontogenesis of the gut occurred between 3 dpf (mouth opening) and 7 dpf (end of exocrine pancreas differentiation). The presence of a wide range of digestive enzymes, already active at earlier zebrafish larval stages, closely related with the omnivorous diet of this species. Increasing enzyme activities were found with increasing age, probably in relation with intestinal mucosa folding and consequent absorption surface increase. J. Exp. Zool. (Mol. Dev. Evol.) 324B: 699-706, 2015. © 2015 Wiley Periodicals, Inc. PMID:26477613

  15. Occurrence and origin of sensitivity toward difenoconazole in zebrafish (Danio reio) during different life stages.

    Science.gov (United States)

    Mu, Xiyan; Chai, Tingting; Wang, Kai; Zhang, Jie; Zhu, Lizhen; Li, Xuefeng; Wang, Chengju

    2015-03-01

    We report here an investigation of the mechanisms contributing to the divergent sensitivity toward the triazole fungicide difenoconazole of zebrafish (Danio reio) during different life stages. Adult and embryonic zebrafish were exposed to three different concentrations of difenoconazole (0.01, 0.5 and 1.0mg/L). The death rate, bioaccumulation of difenoconazole, oxidative stress parameters and transcription of related genes were tested at 4 and 8 days post-exposure (dpe). The death rate for adult zebrafish was much higher than that of the embryos at an exposure concentration of 1.0mg/L at both 4 and 8 dpe. The concentrations of difenoconazole in both the embryos and adult fish were similar, except for the group exposed to 0.01mg/L difenoconazole. A decrease in antioxidant enzyme activities was observed in both the embryos and the livers of adult fish after exposure to difenoconazole. Significant lipid peroxidation was found in the livers of adult fish in all exposure groups at 8 dpe, but was not observed in the treated embryos. The gene transcription response of the embryos toward difenoconazole was different from that in the livers of adult fish at 4 dpe. At 8 dpe, the modification in the transcription of the tested genes in the embryos and adult fish was similar, except for the genes related to the synthesis of sterols.

  16. Adult zebrafish model for pneumococcal pathogenesis.

    Science.gov (United States)

    Saralahti, Anni; Piippo, Hannaleena; Parikka, Mataleena; Henriques-Normark, Birgitta; Rämet, Mika; Rounioja, Samuli

    2014-02-01

    Streptococcus pneumoniae (pneumococcus) is a leading cause of community acquired pneumonia, septicemia, and meningitis. Due to incomplete understanding of the host and bacterial factors contributing to these diseases optimal treatment and prevention methods are lacking. In the present study we examined whether the adult zebrafish (Danio rerio) can be used to investigate the pathophysiology of pneumococcal diseases. Here we show that both intraperitoneal and intramuscular injections of the pneumococcal strain TIGR4 cause a fulminant, dose-dependent infection in adult zebrafish, while isogenic mutant bacteria lacking the polysaccharide capsule, autolysin, or pneumolysin are attenuated in the model. Infection through the intraperitoneal route is characterized by rapid expansion of pneumococci in the bloodstream, followed by penetration of the blood-brain barrier and progression to meningitis. Using Rag1 mutant zebrafish, which are devoid of somatic recombination and thus lack adaptive immune responses, we show that clearance of pneumococci in adult zebrafish depends mainly on innate immune responses. In conclusion, this study provides evidence that the adult zebrafish can be used as a model for a pneumococcal infection, and that it can be used to study both host and bacterial factors involved in the pathogenesis. However, our results do not support the use of the zebrafish in studies on the role of adaptive immunity in pneumococcal disease or in the development of new pneumococcal vaccines.

  17. Pharmacological study of the light/dark preference test in zebrafish (Danio rerio): Waterborne administration.

    Science.gov (United States)

    Magno, Lílian Danielle Paiva; Fontes, Aldo; Gonçalves, Beatriz Maria Necy; Gouveia, Amauri

    2015-08-01

    Anxiety is a complex disorder; thus, its mechanisms remain unclear. Zebrafish (Danio rerio) are a promising pharmacological model for anxiety research. Light/dark preference test is a behaviorally validated measure of anxiety in zebrafish; however, it requires pharmacological validation. We sought to evaluate the sensitivity of the light/dark preference test in adult zebrafish by immersing them in drug solutions containing clonazepam, buspirone, imipramine, fluoxetine, paroxetine, haloperidol, risperidone, propranolol, or ethanol. The time spent in the dark environment, the latency time to first crossing, and the number of midline crossings were analyzed. Intermediate concentrations of clonazepam administered for 600s decreased the time spent in the dark and increased locomotor activity. Buspirone reduced motor activity. Imipramine and fluoxetine increased time spent in the dark and the first latency, and decreased the number of alternations. Paroxetine did not alter the time in the dark; however, it increased the first latency time and decreased locomotor activity. Haloperidol decreased the time spent in the dark at low concentrations. Risperidone and propranolol did not change any parameters. Ethanol reduced the time spent in the dark and increased the number of crossings at intermediate concentrations. These results corroborate the previous work using intraperitoneal drug administration in zebrafish and rodents, suggesting that water drug delivery in zebrafish can effectively be used as an animal anxiety model. PMID:26026898

  18. Fluoride caused thyroid endocrine disruption in male zebrafish (Danio rerio).

    Science.gov (United States)

    Jianjie, Chen; Wenjuan, Xue; Jinling, Cao; Jie, Song; Ruhui, Jia; Meiyan, Li

    2016-02-01

    Excessive fluoride in natural water ecosystem has the potential to detrimentally affect thyroid endocrine system, but little is known of such effects or underlying mechanisms in fish. In the present study, we evaluated the effects of fluoride on growth performance, thyroid histopathology, thyroid hormone levels, and gene expressions in the HPT axis in male zebrafish (Danio rerio) exposed to different determined concentrations of 0.1, 0.9, 2.0 and 4.1 M of fluoride to investigate the effects of fluoride on thyroid endocrine system and the potential toxic mechanisms caused by fluoride. The results indicated that the growth of the male zebrafish used in the experiments was significantly inhibited, the thyroid microtrastructure was changed, and the levels of T3 and T4 were disturbed in fluoride-exposed male fish. In addition, the expressional profiles of genes in HPT axis displayed alteration. The expressions of all studied genes were significantly increased in all fluoride-exposed male fish after exposure for 45 days. The transcriptional levels of corticotrophin-releasing hormone (CRH), thyroid-stimulating hormone (TSH), thyroglobulin (TG), sodium iodide symporter (NIS), iodothyronine I (DIO1), and thyroid hormone receptor alpha (TRα) were also elevated in all fluoride-exposed male fish after 90 days of exposure, while the inconsistent expressions were found in the mRNA of iodothyronineⅡ (DIO2), UDP glucuronosyltransferase 1 family a, b (UGT1ab), transthyretin (TTR), and thyroid hormone receptor beta (TRβ). These results demonstrated that fluoride could notably inhibit the growth of zebrafish, and significantly affect thyroid endocrine system by changing the microtrastructure of thyroid, altering thyroid hormone levels and endocrine-related gene expressions in male zebrafish. All above indicated that fluoride could pose a great threat to thyroid endocrine system, thus detrimentally affected the normal function of thyroid of male zebrafish.

  19. Developmental exposure of zebrafish (Danio rerio) to 17α-ethinylestradiol affects non-reproductive behavior and fertility as adults, and increases anxiety in unexposed progeny.

    Science.gov (United States)

    Volkova, Kristina; Reyhanian Caspillo, Nasim; Porseryd, Tove; Hallgren, Stefan; Dinnétz, Patrik; Porsch-Hällström, Inger

    2015-07-01

    Exposure to estrogenic endocrine disruptors (EDCs) during development affects fertility, reproductive and non-reproductive behavior in mammals and fish. These effects can also be transferred to coming generations. In fish, the effects of developmental EDC exposure on non-reproductive behavior are less well studied. Here, we analyze the effects of 17α-ethinylestradiol (EE2) on anxiety, shoaling behavior and fertility in zebrafish after developmental treatment and remediation in clean water until adulthood. Zebrafish embryos were exposed from day 1 to day 80 post fertilization to actual concentrations of 1.2 and 1.6ng/L EE2. After remediation for 82days non-reproductive behavior and fertilization success were analyzed in both sexes. Males and females from the 1.2ng/L group, as well as control males and females, were bred, and behavior of the untreated F1 offspring was tested as adults. Developmental treatment with 1.2 and 1.6ng/L EE2 significantly increased anxiety in the novel tank test and increased shoaling intensity in both sexes. Fertilization success was significantly reduced by EE2 in both sexes when mated with untreated fish of opposite sex. Progeny of fish treated with 1.2ng/L EE2 showed increased anxiety in the novel tank test and increased light avoidance in the scototaxis test compared to control offspring. In conclusion, developmental exposure of zebrafish to low doses of EE2 resulted in persistent changes in behavior and fertility. The behavior of unexposed progeny was affected by their parents' exposure, which might suggest transgenerational effects. PMID:26072466

  20. Toxicity and teratogenesis in zebrafish embryos (Danio rerio)

    OpenAIRE

    Strecker, Ruben

    2013-01-01

    The present thesis gives an overview about the potentials zebrafish embryos can be used for in the area of ecotoxicology. The first chapter summarizes the outcome of the ZFET (Zebrafish Embryo Toxicity Test) OECD validation study, an international attempt for the standardization and development of an embryo toxicity test as an (animal) alternative test to the acute (adult) fish test which is a mandatory component of chemical registration worldwide. The overall reproducibility of the ZFET w...

  1. Time-place learning in the zebrafish (Danio rerio).

    Science.gov (United States)

    Moura, Clarissa de Almeida; Luchiari, Ana Carolina

    2016-07-01

    Animals exhibit activity cycles that repeat over days. The most noteworthy cyclical behaviors are related to forraging, which generally occur at the same times and locations. The synchronization of animal activities via the association of different places at different times for the occurrence of relevant biological events is known as time-place learning (TPL). In the present study, we used zebrafish (Danio rerio) to test time-place learning based on a different stimulus: social reinforcement. Fish were not only able to associate time and place of the social stimulus, but also displayed anticipatory activity prior to the arrival of the stimulus. Furthermore, we show that the group of conspecifics is an relevant stimulus for time-place learning tasks, while other studies have only used food. PMID:27089863

  2. Hepatic gene expression profiling in zebrafish (Danio rerio) exposed to the fungicide chlorothalonil.

    Science.gov (United States)

    Sánchez Garayzar, Anny B; Bahamonde, Paulina A; Martyniuk, Christopher J; Betancourt, Miguel; Munkittrick, Kelly R

    2016-09-01

    Chlorothalonil (tetrachloroisophtalonitrile) is a fungicide that is widely used on agricultural crops around the world and as such, it is a ubiquitous aquatic contaminant. Despite high usage, the effects of this fungicide on non-target aquatic organisms have not been fully investigated. The aim of the present study was to (1) determine the effects of chlorothalonil toxicity on adult male zebrafish (Danio rerio) and (2) characterize the effects of chlorothalonil on gene expression patterns in the liver using two different concentrations of the fungicide, 0.007mg/L (environmentally-relevant) and 0.035mg/L (sublethal). These concentrations were selected from range-finding experiments that showed that zebrafish survival was significantly different from control animals at concentrations higher than 0.035mg/L but not below. Male zebrafish in both treatments of chlorothalonil showed a decrease in liversomatic index. A commercial D. rerio microarray (4×44K) was used to determine gene expression profiles in male zebrafish liver following a 96h toxicological assay. Microarray analysis revealed that males exposed to both 0.007mg/L or 0.035mg/L of chlorothalonil showed increased transcriptional sub-networks related to cell division and DNA damage and decreased expression of gene networks associated with reproduction, immunity, and xenobiotic clearance. This study improves knowledge regarding whole animal exposures to chlorothalonil and identifies molecular signaling cascades that are sensitive to this fungicide in the fish liver. PMID:27264782

  3. Identification and characterisation of an androgen receptor from zebrafish Danio rerio

    DEFF Research Database (Denmark)

    Jørgensen, Anne; Andersen, Ole; Bjerregaard, Poul;

    2007-01-01

    zebrafish Danio rerio. The predicted protein of 868 residues has an estimated calculated molecular weight of 96 kDa. The amino acid sequence of the zebrafish AR (zfRA) shows high homology with other vertebrate ARs. The highest overall similarity was 82% to ARs from fathead minnow (Pimephales promelas...

  4. Xenobiotics Produce Distinct Metabolomic Responses in Zebrafish Larvae (Danio rerio).

    Science.gov (United States)

    Huang, Susie S Y; Benskin, Jonathan P; Chandramouli, Bharat; Butler, Heather; Helbing, Caren C; Cosgrove, John R

    2016-06-21

    Sensitive and quantitative protocols for characterizing low-dose effects are needed to meet the demands of 21st century chemical hazard assessment. To test the hypothesis that xenobiotic exposure at environmentally relevant concentrations produces specific biochemical fingerprints in organisms, metabolomic perturbations in zebrafish (Danio rerio) embryo/larvae were measured following 24 h exposures to 13 individual chemicals covering a wide range of contaminant classes. Measured metabolites (208 in total) included amino acids, biogenic amines, fatty acids, bile acids, sugars, and lipids. The 96-120 h post-fertilization developmental stage was the most appropriate model for detecting xenobiotic-induced metabolomic perturbations. Metabolomic fingerprints were largely chemical- and dose-specific and were reproducible in multiple exposures over a 16-month period. Furthermore, chemical-specific responses were detected in the presence of an effluent matrix; importantly, in the absence of morphological response. In addition to improving sensitivity for detecting biological responses to low-level xenobiotic exposures, these data can aid the classification of novel contaminants based on the similarity of metabolomic responses to well-characterized "model" compounds. This approach is clearly of use for rapid, sensitive, and specific analyses of chemical effect on organisms, and can supplement existing methods, such as the Zebrafish Embryo Toxicity assay (OECD TG236), with molecular-level information. PMID:27232715

  5. The first characterization of multidrug and toxin extrusion (MATE/SLC47) proteins in zebrafish (Danio rerio).

    Science.gov (United States)

    Lončar, Jovica; Popović, Marta; Krznar, Petra; Zaja, Roko; Smital, Tvrtko

    2016-01-01

    Multidrug and toxin extrusion (MATE) proteins are involved in the extrusion of endogenous compounds and xenobiotics across the plasma membrane. They are conserved from bacteria to mammals, with different numbers of genes within groups. Here, we present the first data on identification and functional characterization of Mate proteins in zebrafish (Danio rerio). Phylogenetic analysis revealed six Mates in teleost fish, annotated as Mate3-8, which form a distinct cluster separated from the tetrapod MATEs/Mates. Synteny analysis showed that zebrafish mate genes are orthologous to human MATEs. Gene expression analysis revealed that all the mate transcripts were constitutively and differentially expressed during embryonic development, followed by pronounced and tissue-specific expression in adults. Functional analyses were performed using transport activity assays with model substrates after heterologous overexpression of five zebrafish Mates in HEK293T cells. The results showed that zebrafish Mates interact with both physiological and xenobiotic substances but also substantially differ with respect to the interacting compounds and interaction strength in comparison to mammalian MATEs/Mates. Taken together, our data clearly indicate a potentially important role for zebrafish Mate transporters in zebrafish embryos and adults and provide a basis for detailed functional characterizations of single zebrafish Mate transporters. PMID:27357367

  6. Automated visual choice discrimination learning in zebrafish (Danio rerio).

    Science.gov (United States)

    Mueller, Kaspar P; Neuhauss, Stephan C F

    2012-03-01

    Training experimental animals to discriminate between different visual stimuli has been an important tool in cognitive neuroscience as well as in vision research for many decades. Current methods used for visual choice discrimination training of zebrafish require human observers for response tracking, stimulus presentation and reward delivery and, consequently, are very labor intensive and possibly experimenter biased. By combining video tracking of fish positions, stimulus presentation on computer monitors and food delivery by computer-controlled electromagnetic valves, we developed a method that allows for a fully automated training of multiple adult zebrafish to arbitrary visual stimuli in parallel. The standardized training procedure facilitates the comparison of results across different experiments and laboratories and contributes to the usability of zebrafish as vertebrate model organisms in behavioral brain research and vision research. PMID:22744784

  7. Limb Regeneration is Impaired in an Adult Zebrafish Model of Diabetes Mellitus

    OpenAIRE

    Olsen, Ansgar S.; Sarras, Michael P.; Intine, Robert V.

    2010-01-01

    The zebrafish (Danio Rerio) is an established model organism for the study of developmental processes, human disease and tissue regeneration. We report that limb regeneration is severely impaired in our newly developed adult zebrafish model of type I diabetes. Intraperitoneal streptozocin injection of adult, wild type zebrafish results in a sustained hyperglycemic state as determined by elevated fasting blood glucose values and increased glycation of serum protein. Serum insulin levels are al...

  8. Copper acutely impairs behavioral function and muscle acetylcholinesterase activity in zebrafish (Danio rerio).

    Science.gov (United States)

    Haverroth, Gabriela M B; Welang, Chariane; Mocelin, Riciéri N; Postay, Daniela; Bertoncello, Kanandra T; Franscescon, Francini; Rosemberg, Denis B; Dal Magro, Jacir; Dalla Corte, Cristiane L

    2015-12-01

    Copper is a heavy metal found at relatively high concentrations in surface waters around the world. Copper is a micronutrient at low concentrations and is essential to several organisms. At higher concentrations copper can become toxic, which reveal the importance of studying the toxic effects of this metal on the aquatic life. Thus, the objective of this study was to evaluate the toxic effects of copper on the behavior and biochemical parameters of zebrafish (Danio rerio). Zebrafish were exposed for 24h at a concentration of 0.006 mg/L Cu. After the exposure period, behavioral profile of animals was recorded through 6 min using two different apparatuses tests: the Novel Tank and the Light-Dark test. After behavioral testing, animals were euthanized with a solution of 250 mg/L of tricaine (MS-222). Brain, muscle, liver and gills were extracted for analysis of parameters related to oxidative stress and accumulation of copper in these tissues. Acetylcholinesterase (AChE) activity was determined in brain and muscle. Results showed acute exposure to copper induces significant changes in behavioral profile of zebrafish by changing locomotion and natural tendency to avoid brightly lit area. On the other hand, there were no significant effects on parameters related to oxidative stress. AChE activity decreased significantly in zebrafish muscle, but there were no significant changes in cerebral AChE activity. Copper levels in tissues did not increase significantly compared to the controls. Taken together, these results indicate that a low concentration of copper can acutely affect behavioral profile of adult zebrafish which could be partially related to an inhibition on muscle AChE activity. These results reinforce the need of additional tests to establishment of safe copper concentrations to aquatic organisms and the importance of behavioral parameters in ecotoxicological studies.

  9. Natural preference of zebrafish (Danio rerio for a dark environment

    Directory of Open Access Journals (Sweden)

    Serra E.L.

    1999-01-01

    Full Text Available The zebrafish (Danio rerio has been used as a model in neuroscience but knowledge about its behavior is limited. The aim of this study was to determine the preference of this fish species for a dark or light environment. Initially we used a place preference test and in a second experiment we applied an exit latency test. A two-chamber aquarium was used for the preference test. The aquarium consisted of a black chamber and a white chamber. In the first experiment the animal was placed in the aquarium and the time spent in the two compartments was recorded for 10 min. More time was spent in the black compartment (Wilcoxon matched-pairs signed-rank test, T = 7, N1 = N2 = 18, P = 0.0001. In the second experiment the animal was placed in the black or white compartment and the time it took to go from the initial compartment to the opposite one was recorded. The test lasted a maximum of 10 min. The results showed that the animal spent more time to go from the black to the white compartment (Mann-Whitney rank sum test, T = 48, N1 = 9, N2 = 8, P<0.0230. These data suggest that this fish species has a natural preference for a dark environment and this characteristic can be very useful for the development of new behavioral paradigms for fish.

  10. Endocrine-disrupting effect of the ultraviolet filter benzophenone-3 in zebrafish, Danio rerio.

    Science.gov (United States)

    Kinnberg, Karin L; Petersen, Gitte I; Albrektsen, Mette; Minghlani, Mita; Awad, Suad Mohamud; Holbech, Bente F; Green, John W; Bjerregaard, Poul; Holbech, Henrik

    2015-12-01

    The chemical ultraviolet (UV) filter benzophenone-3 (BP-3) is suspected to be an endocrine disruptor based on results from in vitro and in vivo testing. However, studies including endpoints of endocrine adversity are lacking. The present study investigated the potential endocrine-disrupting effects of BP-3 in zebrafish (Danio rerio) in the Fish Sexual Development Test (Organisation for Economic Co-operation and Development TG 234) and a 12-d adult male zebrafish study. In TG 234, exposure from 0 d to 60 d posthatch caused a monotone dose-dependent skewing of the phenotypic sex ratio toward fewer males and more female zebrafish (no observed effect concentration [NOEC]: 191 μg/L, lowest observed effect concentration [LOEC]: 388 μg/L). Besides, gonad maturation was affected in both female fish (NOEC 191 μg/L, LOEC 388 μg/L) and male fish (NOEC 388 μg/L, LOEC 470 μg/L). Exposure to BP-3 did not affect the vitellogenin concentration in TG 234. After 12 d exposure of adult male zebrafish, a slight yet significant increase in the vitellogenin concentration was observed at 268 μg/L but not at 63 μg/L and 437 μg/L BP-3. Skewing of the sex ratio is a marker of an endocrine-mediated mechanism as well as a marker of adversity, and therefore the conclusion of the present study is that BP-3 is an endocrine-disrupting chemical in accordance with the World Health Organization's definition. PMID:26118430

  11. Identification of multiple integrin β1 homologs in zebrafish (Danio rerio

    Directory of Open Access Journals (Sweden)

    Boot-Handford Raymond P

    2006-06-01

    Full Text Available Abstract Background Integrins comprise a large family of α,β heterodimeric, transmembrane cell adhesion receptors that mediate diverse essential biological functions. Higher vertebrates possess a single β1 gene, and the β1 subunit associates with a large number of α subunits to form the major class of extracellular matrix (ECM receptors. Despite the fact that the zebrafish (Danio rerio is a rapidly emerging model organism of choice for developmental biology and for models of human disease, little is currently known about β1 integrin sequences and functions in this organism. Results Using RT-PCR, complete coding sequences of zebrafish β1 paralogs were obtained from zebrafish embryos or adult tissues. The results show that zebrafish possess two β1 paralogs (β1–1 and β1–2 that have a high degree of identity to other vertebrate β1 subunits. In addition, a third, more divergent, β1 paralog is present (β1–3, which may have altered ligand-binding properties. Zebrafish also have other divergent β1-like transcripts, which are C-terminally truncated forms lacking the transmembrane and cytoplasmic domains. Together with β1–3 these truncated forms comprise a novel group of β1 paralogs, all of which have a mutation in the ADMIDAS cation-binding site. Phylogenetic and genomic analyses indicate that the duplication that gave rise to β1–1 and β1–2 occurred after the divergence of the tetrapod and fish lineages, while a subsequent duplication of the ancestor of β1–2 may have given rise to β1–3 and an ancestral truncated paralog. A very recent tandem duplication of the truncated β1 paralogs appears to have taken place. The different zebrafish β1 paralogs have varied patterns of temporal expression during development. β1–1 and β1–2 are ubiquitously expressed in adult tissues, whereas the other β1 paralogs generally show more restricted patterns of expression. Conclusion Zebrafish have a large set of integrin β1

  12. DANIO-CODE: Toward an Encyclopedia of DNA Elements in Zebrafish.

    Science.gov (United States)

    Tan, Haihan; Onichtchouk, Daria; Winata, Cecilia

    2016-02-01

    The zebrafish has emerged as a model organism for genomics studies. The symposium "Toward an encyclopedia of DNA elements in zebrafish" held in London in December 2014, was coorganized by Ferenc Müller and Fiona Wardle. This meeting is a follow-up of a similar previous workshop held 2 years earlier and represents a push toward the formalization of a community effort to annotate functional elements in the zebrafish genome. The meeting brought together zebrafish researchers, bioinformaticians, as well as members of established consortia, to exchange scientific findings and experience, as well as to discuss the initial steps toward the formation of a DANIO-CODE consortium. In this study, we provide the latest updates on the current progress of the consortium's efforts, opening up a broad invitation to researchers to join in and contribute to DANIO-CODE.

  13. Distribution of carnosine-like peptides in the nervous system of developing and adult zebrafish (Danio rerio) and embryonic effects of chronic carnosine exposure

    OpenAIRE

    Senut, Marie-Claude; Azher, Seema; Margolis, Frank L.; Patel, Kamakshi; Mousa, Ahmad; Majid, Arshad

    2009-01-01

    Carnosine-like peptides (carnosine-LP) are a family of histidine derivatives that are present in the nervous system of various species and that exhibit antioxidant, anti-matrix-metalloproteinase, anti-excitotoxic, and free-radical scavenging properties. They are also neuroprotective in animal models of cerebral ischemia. Although the function of carnosine-LP is largely unknown, the hypothesis has been advanced that they play a role in the developing nervous system. Since the zebrafish is an e...

  14. Toxicity assessment of combined fluoroquinolone and tetracycline exposure in zebrafish (Danio rerio).

    OpenAIRE

    Zhang, Y; Wang, X.; Yin, X.; Shi, M.; Dahlgren, RA; Wang, H

    2016-01-01

    Fluoroquinolones (FQs) and tetracyclines (TCs), the two β-diketone antibiotics (DKAs), are two frequently detected pollutants in the environment; however, little data are available on their combined toxicity to zebrafish (Danio rerio). This study reports that toxicologic effects of combined DKA (FQs-TCs) exposure on zebrafish were comparable with or slightly less than those of TCs alone, showing that TCs played a major toxicologic role in the mixtures. The effects of FQs, TCs, and DKAs on mal...

  15. Dimethyl Sulfoxide (DMSO) Exacerbates Cisplatin-induced Sensory Hair Cell Death in Zebrafish (Danio rerio)

    OpenAIRE

    Uribe, Phillip M.; Mueller, Melissa A.; Gleichman, Julia S.; Kramer, Matthew D.; Qi Wang; Martha Sibrian-Vazquez; Strongin, Robert M.; Peter S Steyger; Douglas A Cotanche; Matsui, Jonathan I.

    2013-01-01

    Inner ear sensory hair cells die following exposure to aminoglycoside antibiotics or chemotherapeutics like cisplatin, leading to permanent auditory and/or balance deficits in humans. Zebrafish (Danio rerio) are used to study drug-induced sensory hair cell death since their hair cells are similar in structure and function to those found in humans. We developed a cisplatin dose-response curve using a transgenic line of zebrafish that expresses membrane-targeted green fluorescent protein under ...

  16. Sexual disruption in zebrafish (Danio rerio) exposed to mixtures of 17α-ethinylestradiol and 17β-trenbolone

    DEFF Research Database (Denmark)

    Örn, Stefan; Holbech, Henrik; Norrgren, Leif

    2016-01-01

    was to evaluate feminization and masculinization effects in zebrafish (Danio rerio) exposed to combinations of two synthetic steroid hormones detected in environmental waters: the androgen 17β-trenbolone (Tb) and the oestrogen 17α-ethinylestradiol (EE2). Juvenile zebrafish were exposed between days 20 and 60 post...... differentiation in zebrafish and lead to sexual disruption....

  17. Vascular toxicity of silver nanoparticles to developing zebrafish (Danio rerio).

    Science.gov (United States)

    Gao, Jiejun; Mahapatra, Cecon T; Mapes, Christopher D; Khlebnikova, Maria; Wei, Alexander; Sepúlveda, Marisol S

    2016-11-01

    Nanoparticles (NPs, 1-100 nm) can enter the environment and result in exposure to humans and other organisms leading to potential adverse health effects. The aim of the present study is to evaluate the effects of early life exposure to polyvinylpyrrolidone-coated silver nanoparticles (PVP-AgNPs, 50 nm), particularly with respect to vascular toxicity on zebrafish embryos and larvae (Danio rerio). Previously published data has suggested that PVP-AgNP exposure can inhibit the expression of genes within the vascular endothelial growth factor (VEGF) signaling pathway, leading to delayed and abnormal vascular development. Here, we show that early acute exposure (0-12 h post-fertilization, hpf) of embryos to PVP-AgNPs at 1 mg/L or higher results in a transient, dose-dependent induction in VEGF-related gene expression that returns to baseline levels at hatching (72 hpf). Hatching results in normoxia, negating the effects of AgNPs on vascular development. Interestingly, increased gene transcription was not followed by the production of associated proteins within the VEGF pathway, which we attribute to NP-induced stress in the endoplasmic reticulum (ER). The impaired translation may be responsible for the observed delays in vascular development at later stages, and for smaller larvae size at hatching. Silver ion (Ag(+)) concentrations were < 0.001 mg/L at all times, with no significant effects on the VEGF pathway. We propose that PVP-AgNPs temporarily delay embryonic vascular development by interfering with oxygen diffusion into the egg, leading to hypoxic conditions and ER stress. PMID:27499207

  18. Uranium-induced sensory alterations in the zebrafish Danio rerio

    Energy Technology Data Exchange (ETDEWEB)

    Faucher, K., E-mail: kfaucher@hotmail.fr [Laboratoire d' ecotoxicologie des radionucleides (LECO), Institut de Radioprotection et Surete Nucleaire, Centre de Cadarache, Batiment 186, BP3, 13115 Saint Paul lez Durance (France); Floriani, M.; Gilbin, R.; Adam-Guillermin, C. [Laboratoire d' ecotoxicologie des radionucleides (LECO), Institut de Radioprotection et Surete Nucleaire, Centre de Cadarache, Batiment 186, BP3, 13115 Saint Paul lez Durance (France)

    2012-11-15

    The effect of chronic exposure to uranium ions (UO{sub 2}{sup 2+}) on sensory tissues including the olfactory and lateral line systems was investigated in zebrafish (Danio rerio) using scanning electron microscopy. The aim of this study was to determine whether exposure to uranium damaged sensory tissues in fish. The fish were exposed to uranium at the concentration of 250 {mu}g l{sup -1} for 10 days followed by a depuration period of 23 days. Measurements of uranium uptake in different fish organs: olfactory rosettes and bulbs, brain, skin, and muscles, were also determined by ICP-AES and ICP-MS during the entire experimental period. The results showed that uranium displayed a strong affinity for sensory structures in direct contact with the surrounding medium, such as the olfactory and lateral line systems distributed on the skin. A decreasing gradient of uranium concentration was found: olfactory rosettes > olfactory bulbs > skin > muscles > brain. At the end of the experiment, uranium was present in non-negligible quantities in sensory tissues. In parallel, fish exposed to uranium showed severe sensory tissue alterations at the level of the olfactory and lateral line systems. In both sensory systems, the gross morphology was altered and the sensory hair cells were significantly damaged very early after the initiation of exposure (from the 3rd day). At the end of the experiment, after 23 days of depuration, the lateral line system still displayed slight tissue alterations, but approximately 80% of the neuromasts in this system had regenerated. In contrast, the olfactory system took more time to recover, as more than half of the olfactory rosettes observed remained destroyed at the end of the experiment. This study showed, for the first time, that uranium is able to damage fish sensory tissues to such an extent that tissue regeneration is delayed.

  19. Effects of depleted uranium on oxidative stress, detoxification, and defence parameters of zebrafish Danio rerio.

    Science.gov (United States)

    Gagnaire, Beatrice; Cavalie, Isabelle; Camilleri, Virginie; Adam-Guillermin, Christelle

    2013-01-01

    In this study, we investigated the effects of depleted uranium (DU), the by-product of nuclear enrichment of uranium, on several parameters related to oxidative stress, detoxification, and the defence system in the zebrafish Danio rerio. Several parameters were recorded: phenoloxidase-like (PO) activity, reactive oxygen species (ROS) production, and 7-ethoxyresrufin-O-deethylase (EROD) activity. Experiments were performed on adult and larvae D. rerio. Adult fish were exposed for 28 days at 20 μg U/L followed by a 27-day depuration period. Eggs of D. rerio were exposed for 4 days at 0, 20, 100, 250, 500, and 1,000 μg U/L. Results showed that DU increased ROS production both in adult and in larvae even at the low concentrations tested and even during the depuration period for adult D. rerio. DU also modified PO-like activity, both in the D. rerio adult and larvae experiments, but in a more transient manner. EROD activity was not modified by DU, but sex effects were shown. Results are discussed by way of comparison with other known effects of uranium in fish. Overall, these results show that the mechanisms of action of DU in fish tend to be similar to the ones existing for mammals. These results encourage the development and use of innate immune biomarkers to understand the effects of uranium and, more generally, radionuclides on the fish immune system. PMID:23052361

  20. Two divergent leptin paralogues in zebrafish (Danio rerio) that originate early in teleostean evolution.

    NARCIS (Netherlands)

    Gorissen, M.H.A.G; Bernier, N.J.; Nabuurs, S.B.; Flik, G.; Huising, M.O.

    2009-01-01

    We describe duplicate leptin genes in zebrafish (Danio rerio) that share merely 24% amino acid identity with each other and only 18% with human leptin. We were also able to retrieve a second leptin gene in medaka (Oryzias latipes). The presence of duplicate leptin genes in these two distantly relate

  1. Phototoxicity of TiO2 nanoparticles to zebrafish (Danio rerio) is dependent on life stage

    Science.gov (United States)

    The zebrafish (Danio rerio) embryo has been increasingly used as a model to evaluate toxicity of manufactured nanomaterials. Many studies indicate that the embryo chorion may protect animals from toxic effects of nanomaterials, suggesting that post-hatch life stages may be more s...

  2. Imaging of human glioblastoma cells and their interactions with mesenchymal stem cells in the zebrafish (Danio rerio embryonic brain

    Directory of Open Access Journals (Sweden)

    Vittori Milos

    2016-06-01

    Full Text Available An attractive approach in the study of human cancers is the use of transparent zebrafish (Danio rerio embryos, which enable the visualization of cancer progression in a living animal.

  3. Reprint of "Pharmacological study of the light/dark preference test in zebrafish (Danio rerio): Waterborne administration".

    Science.gov (United States)

    Magno, Lílian Danielle Paiva; Fontes, Aldo; Gonçalves, Beatriz Maria Necy; Gouveia, Amauri

    2015-12-01

    Anxiety is a complex disorder; thus, its mechanisms remain unclear. Zebrafish (Danio rerio) are a promising pharmacological model for anxiety research. Light/dark preference test is a behaviorally validated measure of anxiety in zebrafish; however, it requires pharmacological validation. We sought to evaluate the sensitivity of the light/dark preference test in adult zebrafish by immersing them in drug solutions containing clonazepam, buspirone, imipramine, fluoxetine, paroxetine, haloperidol, risperidone, propranolol, or ethanol. The time spent in the dark environment, the latency time to first crossing, and the number of midline crossings were analyzed. Intermediate concentrations of clonazepam administered for 600s decreased the time spent in the dark and increased locomotor activity. Buspirone reduced motor activity. Imipramine and fluoxetine increased time spent in the dark and the first latency, and decreased the number of alternations. Paroxetine did not alter the time in the dark; however, it increased the first latency time and decreased locomotor activity. Haloperidol decreased the time spent in the dark at low concentrations. Risperidone and propranolol did not change any parameters. Ethanol reduced the time spent in the dark and increased the number of crossings at intermediate concentrations. These results corroborate the previous work using intraperitoneal drug administration in zebrafish and rodents, suggesting that water drug delivery in zebrafish can effectively be used as an animal anxiety model. PMID:26569548

  4. Depleted uranium disturbs immune parameters in zebrafish, Danio rerio: an ex vivo/in vivo experiment.

    Science.gov (United States)

    Gagnaire, Béatrice; Bado-Nilles, Anne; Sanchez, Wilfried

    2014-10-01

    In this study, we investigated the effects of depleted uranium (DU), the byproduct of nuclear enrichment of uranium, on several parameters related to defence system in the zebrafish, Danio rerio, using flow cytometry. Several immune cellular parameters were followed on kidney leucocytes: cell proportion, cell mortality, phagocytosis activity and associated oxidative burst and lysosomal membrane integrity (LMI). Effects of DU were tested ex vivo after 17 h of contact between DU and freshly isolated leucocytes from 0 to 500 µg DU/L. Moreover, adult zebrafish were exposed in vivo during 3 days at 20 and 250 µg DU/L. Oxidative burst results showed that DU increased reactive oxygen species (ROS) basal level and therefore reduced ROS stimulation index in both ex vivo and in vivo experiments. ROS PMA-stimulated level was also increased at 250 µg DU/L in vivo only. Furthermore, a decrease of LMI was detected after in vivo experiments. Cell mortality was also decreased at 20 µg DU/L in ex vivo experiment. However, phagocytosis activity was not modified in both ex vivo and in vivo experiments. A reduction of immune-related parameters was demonstrated in zebrafish exposed to DU. DU could therefore decrease the ability of fish to stimulate its own immune system which could, in turn, enhance the susceptibility of fish to infection. These results encourage the development and the use of innate immune analysis by flow cytometry in order to understand the effects of DU and more generally radionuclides on fish immune system and response to infectious diseases. PMID:24723161

  5. Effects of the UV filter benzophenone-3 (oxybenzone) at low concentrations in zebrafish (Danio rerio)

    Energy Technology Data Exchange (ETDEWEB)

    Blüthgen, Nancy [University of Applied Sciences Northwestern Switzerland, School of Life Sciences, Gründenstrasse 40, CH‐4132 Muttenz (Switzerland); University of Basel, Division of Molecular and Systems Toxicology, Department of Pharmaceutical Sciences, Klingelbergstrasse 50, CH-4056 Basel (Switzerland); Zucchi, Sara [University of Applied Sciences Northwestern Switzerland, School of Life Sciences, Gründenstrasse 40, CH‐4132 Muttenz (Switzerland); Fent, Karl, E-mail: karl.fent@fhnw.ch [University of Applied Sciences Northwestern Switzerland, School of Life Sciences, Gründenstrasse 40, CH‐4132 Muttenz (Switzerland); Swiss Federal Institute of Technology (ETHZ), Department of Environmental Sciences, CH‐8092 Zürich (Switzerland)

    2012-09-01

    Organic UV filters including benzophenone-3 (BP-3) are widely used to protect humans and materials from damage by UV irradiation. Despite the environmental occurrence of BP-3 in the aquatic environment, little is known about its effects and modes of action. In the present study we assess molecular and physiological effects of BP-3 in adult male zebrafish (Danio rerio) and in eleuthero-embryos by a targeted gene expression approach focusing on the sex hormone system. Fish and embryos are exposed for 14 days and 120 hours post fertilization, respectively, to 2.4–312 μg/L and 8.2–438 μg/L BP-3. Chemical analysis of water and fish demonstrates that BP-3 is partly transformed to benzophenone-1 (BP-1) and both compounds are accumulated in adult fish. Biotransformation to BP-1 is absent in eleuthero-embryos. BP-3 exposure leads to similar alterations of gene expression in both adult fish and eleuthero-embryos. In the brain of adult males esr1, ar and cyp19b are down-regulated at 84 μg/L BP-3. There is no induction of vitellogenin expression by BP-3, both at the transcriptional and protein level. An overall down-regulation of the hsd3b, hsd17b3, hsd11b2 and cyp11b2 transcripts is observed in the testes, suggesting an antiandrogenic activity. No histological changes were observed in the testes after BP-3 treatment. The study leads to the conclusion that low concentrations of BP-3 exhibit similar multiple hormonal activities at the transcription level in two different life stages of zebrafish. Forthcoming studies should show whether this translates to additional physiological effects. Highlights: ► Activity of UV filter benzophenone-3 (BP-3) is assessed in zebrafish. ► BP-3 is partly metabolized to benzophenone-1 by adult fish but not embryos. ► Alterations of gene expression are similar in adult males and embryos. ► Gene expression alterations point to multiple hormonal activity of BP-3.

  6. Nuclear Transfer of Embryonic Cell Nuclei to Non-enucleated Eggs in Zebrafish, Danio rerio

    Directory of Open Access Journals (Sweden)

    Manabu Hattori, Hisashi Hashimoto, Ekaterina Bubenshchikova, Yuko Wakamatsu

    2011-01-01

    Full Text Available We previously established a novel method for nuclear transfer in medaka (Oryzias latipes using non-enucleated, diploidized eggs as recipients for adult somatic cell nuclei. Here we report the first attempt to apply this method to another fish species. To examine suitability of using non-enucleated eggs as recipients for nuclear transfer in the zebrafish (Danio rerio, we transferred blastula cell nuclei from a wild-type donor strain to non-enucleated, unfertilized eggs from a golden recipient strain. As a result, 31 of 184 (16.8% operated eggs developed normally and reached the adult stage. Twenty-eight (15.2% of these transplants showed wild-type phenotype and the remaining three (1.6% were golden. Except for one individual that exhibited diploid/tetraploid mosaicism, all of the wild-type nuclear transplants were either triploid or diploid. While all of 19 triploid transplants were infertile, a total of six transplants (21.4% were fertile (five of the eight diploid transplants and one transplant exhibiting ploidy mosaicism. Except for one diploid individual, all of the fertile transplants transferred both the wild-type golden gene allele (slc24a5 as well as the phenotype, the wild-type body color, to their F1 and F2 progeny in a typical Mendelian fashion. PCR analysis of slc24a5 suggested that triploidy originated from a fused nucleus in the diploid donor and haploid recipient nuclei, and that the sole origin of diploidy was the diploid donor nucleus. The results of the present study demonstrated the suitability of using non-enucleated eggs as recipients for nuclear transfer experiments in zebrafish.

  7. Bezafibrate, a lipid-lowering pharmaceutical, as a potential endocrine disruptor in male zebrafish (Danio rerio).

    Science.gov (United States)

    Velasco-Santamaría, Yohana M; Korsgaard, Bodil; Madsen, Steffen S; Bjerregaard, Poul

    2011-09-01

    Fibrates are pharmaceuticals commonly used to control hypercholesterolemia in humans and they are frequently detected in the freshwater environment. Since cholesterol is the precursor of all steroid hormones, it is suspected that low cholesterol levels will impact steroidogenesis. However, the effect of fibrates on fish reproductive endocrinology is not clear; therefore the aim of the present study was to evaluate the effect of bezafibrate (BZF) on gonadal steroidogenesis and spermatogenesis of zebrafish (Danio rerio). For this purpose, adult males were exposed orally to 1.7, 33 and 70 mg BZF/g food for 21 days. Blood and gonads were collected after 48 h, 7 days and 21 days to evaluate plasma cholesterol and plasma 11-ketotestosterone (11-KT). The expression of gonadal genes involved in the steroidogenesis was quantified to determine a potential mechanism of action, likewise the effect on spermatogenesis was evaluated by examining gonadal histopathology. A time dependent monotonic decrease in the plasma cholesterol concentration was observed in fish exposed to BZF. Plasma 11-KT decreased significantly after 21 days of exposure in fish exposed to the high concentration of BZF. Different gene expression patterns were observed: down-regulation in ppara and pparg mRNA levels was observed in fish exposed to the higher concentrations after 48 h; however, the expression of pparg increased after 21 days. After 21 days an increase in the star and cyp17a1 mRNA expression was observed in fish exposed to 70 mg BZF/g food. Sampling time and bezafibrate concentration explained 52.4% and 20%, respectively, of the gene expression variability. Gonadal histology revealed the presence of germ cell syncytia in the tubular lumen of fish exposed to bezafibrate and also an increased number of cysts containing spermatocytes, which indicate testicular degeneration. The study shows that bezafibrate exerts a hypocholesterolemic effect in adult male zebrafish and its potential as an endocrine

  8. Infection and immunity against Ichthyophthirius multifiliis in zebrafish (Danio rerio)

    DEFF Research Database (Denmark)

    Jørgensen, Louise von Gersdorff

    2016-01-01

    level of immunity against the disease. Zebrafish are however, known to be more resilient towards the disease than channel catfish but the pathology and the ability to obtain protection is unknown. In this study a primary infection in the gills of zebrafish was described and the subsequent acquirement...... following secondary infection (challenge) only one of the survivor fish died. This study demonstrates that zebrafish are susceptible to I. multifiliis and that gill pathology is similar to the situation observed in rainbow trout. Furthermore, zebrafish are able to acquire immunity against white spot disease...

  9. GROWTH AND BEHAVIOR OF LARVAL ZEBRAFISH Danio rerio FED A PROCESSED DIET, LIVE FOOD, OR THE COMBINATION

    Science.gov (United States)

    Because Zebrafish (Danio rerio) have become a popular and important model for scientific research, the capability to rear larval zebrafish to adulthood is of great importance. Recently research examining the effects of diet (live versus processed) have been published. In the cu...

  10. A retrospective study of the prevalence and classification of intestinal neoplasia in zebrafish (Danio rerio).

    Science.gov (United States)

    Paquette, Colleen E; Kent, Michael L; Buchner, Cari; Tanguay, Robert L; Guillemin, Karen; Mason, Timothy J; Peterson, Tracy S

    2013-06-01

    For over a decade, spontaneous intestinal neoplasia has been observed in zebrafish (Danio rerio) submitted to the ZIRC (Zebrafish International Resource Center) diagnostic service. In addition, zebrafish displayed preneoplastic intestinal changes including hyperplasia, dysplasia, and enteritis. A total of 195 zebrafish, representing 2% of the total fish submitted to the service, were diagnosed with these lesions. Neoplastic changes were classified either as adenocarcinoma or small cell carcinoma, with a few exceptions (carcinoma not otherwise specified, tubular adenoma, and tubulovillous adenoma). Tumor prevalence appeared similarly distributed between sexes and generally occurred in zebrafish greater than 1 year of age, although neoplastic changes were observed in fish 6 months of age. Eleven lines displayed these preneoplastic and neoplastic changes, including wild-types and mutants. Affected zebrafish originated from 18 facilities, but the majority of fish were from a single zebrafish research facility (hereafter referred to as the primary facility) that has submitted numerous samples to the ZIRC diagnostic service. Zebrafish from the primary facility submitted as normal sentinel fish demonstrate that these lesions are most often subclinical. Fish fed the diet from the primary facility and held at another location did not develop intestinal lesions, indicating that diet is not the etiologic agent.

  11. Zebrafish (Danio rerio): A Potential Model for Toxinological Studies.

    Science.gov (United States)

    Vargas, Rafael Antonio; Sarmiento, Karen; Vásquez, Isabel Cristina

    2015-10-01

    Zebrafish are an emerging basic biomedical research model that has multiple advantages compared with other research models. Given that biotoxins, such as toxins, poisons, and venoms, represent health hazards to animals and humans, a low-cost biological model that is highly sensitive to biotoxins is useful to understand the damage caused by such agents and to develop biological tests to prevent and reduce the risk of poisoning in potential cases of bioterrorism or food contamination. In this article, a narrative review of the general aspects of zebrafish as a model in basic biomedical research and various studies in the field of toxinology that have used zebrafish as a biological model are presented. This information will provide useful material to beginner students and researchers who are interested in developing toxinological studies with the zebrafish model. PMID:26196742

  12. Individual differences in activity levels in zebrafish (Danio rerio)

    OpenAIRE

    Tran, Steven; Gerlai, Robert

    2013-01-01

    Individual differences and variation in behavioural responses have been identified in many animal species. These differences may be the result of genetic or environmental factors or the interaction between them. Analysis of individual differences in behaviour may be important for many reasons. The zebrafish is a powerful model organism that is rapidly gaining popularity in behavioural brain research. However, individual differences have rarely been explored in zebrafish although significant v...

  13. The Expression of vasa Gene during Zebrafish (Danio rerio) Oogenesis

    Institute of Scientific and Technical Information of China (English)

    XIANG Fang; ZHEN Yan; ZHENG Wen-xuan; DENG Feng-jiao; WANG Xiao-kai; ZHANG Xi-yuan

    2004-01-01

    vasa gene expression pattern during oogenesis of zebrafish was examined using in situ hybridization and fluorescent quantitative RT-PCR. During zebrafish oogensis, vasa mRNA is expressed strongly and uniformly distributed in the cytoplasm in stage Ⅱ oocytes, followed by a distribution among vacuome in stage Ⅲ. Later in stage Ⅳ and Ⅴ, vasa mRNA is enriched at the cortex and finally localized at the cortex. The fluorescent quantitative RT-PCR shows that the quantity of vasa mRNA decreases from stage Ⅱ to stage Ⅲ, but remains relatively invariable from stage Ⅲ to stage Ⅴ. The observed differences in vasa mRNA expression in the different stages of zebrafish oogenesis suggest that vasa gene plays an important role during oogenesis.

  14. Ultrastructural effects on gill, muscle, and gonadal tissues induced in zebrafish (Danio rerio) by a waterborne uranium exposure

    Energy Technology Data Exchange (ETDEWEB)

    Barillet, Sabrina, E-mail: sabrina.barillet@free.fr [Laboratory of Radioecology and Ecotoxicology, IRSN (Institute for Radiological Protection and Nuclear Safety), DEI/SECRE/LRE, Cadarache, Bat 186, BP 3, 13115 St-Paul-Lez-Durance cedex (France); Larno, Valerie, E-mail: valerie.larno@irsn.fr [Laboratory of Radioecology and Ecotoxicology, IRSN (Institute for Radiological Protection and Nuclear Safety), DEI/SECRE/LRE, Cadarache, Bat 186, BP 3, 13115 St-Paul-Lez-Durance cedex (France); Floriani, Magali, E-mail: magali.floriani@irsn.fr [Laboratory of Radioecology and Ecotoxicology, IRSN (Institute for Radiological Protection and Nuclear Safety), DEI/SECRE/LRE, Cadarache, Bat 186, BP 3, 13115 St-Paul-Lez-Durance cedex (France); Devaux, Alain, E-mail: alain.devaux@entpe.fr [INRA, EFPA Department, 54280, Champenoux and Environmental Science Laboratory, ENTPE, 69518 Vaulx en Velin cedex (France); Adam-Guillermin, Christelle, E-mail: christelle.adam-guillermin@irsn.fr [Laboratory of Radioecology and Ecotoxicology, IRSN (Institute for Radiological Protection and Nuclear Safety), DEI/SECRE/LRE, Cadarache, Bat 186, BP 3, 13115 St-Paul-Lez-Durance cedex (France)

    2010-11-01

    Experiments on adult zebrafish (Danio rerio) were conducted to assess histopathological effects induced on gill, muscle, and gonadal tissues after waterborne uranium exposure. Although histopathology is often employed as a tool for the detection and assessment of xenobiotic-mediated effects in aquatic organisms, few studies have been dedicated to the investigation of histopathological consequences of uranium exposure in fish. Results showed that gill tissue architecture was markedly disrupted. Major symptoms were alterations of the secondary lamellae epithelium (from extensive oedema to desquamation), hyperplasia of chloride cells, and breakdown of the pillar cell system. Muscle histology was also affected. Degeneration and disorganization of myofibrillar sarcomeric pattern as well as abnormal localization of mitochondria within muscle and altered endomysial sheaths were observed. Morphological alterations of spermatozoa within the gonadal tissue were also noticed. This study demonstrated that uranium exposure induced a variety of histological impairments in fish, supporting environmental concerns when uranium contaminates aquatic systems.

  15. The toxicity of a new disinfection by-product, 2,2-dichloroacetamide (DCAcAm), on adult zebrafish (Danio rerio) and its occurrence in the chlorinated drinking water.

    Science.gov (United States)

    Yu, Shilin; Lin, Tao; Chen, Wei; Tao, Hui

    2015-11-01

    The detection method of 2,2-dichloroacetamide (DCAcAm), a new disinfection by-product (DBP) in chlorinated drinking water, was established using a gas chromatograph coupled with a micro-electron capture detector. The chlorinated water samples were taken from ten drinking water treatment plants around Yangtze River or Taihu Lake in China. The concentration of DCAcAm was detected ranging from 0.5 to 1.8μg/L in the waterworks around Yangtze River, and 1.5-2.6μg/L around Taihu Lake. The toxicity of DCAcAm on adult zebrafish was assessed by investigating the metabolism damage with multiple metabolic biomarkers and the accumulation capability with bio-concentration factor. The results showed that DCAcAm could cause the acute metabolism damage and was easily accumulated in zebrafish, and should be extremely cautioned.

  16. Cardiac and metabolic physiology of early larval zebrafish (Danio rerio reflects parental swimming stamina

    Directory of Open Access Journals (Sweden)

    Warren W Burggren

    2012-02-01

    Full Text Available Swimming stamina in adult fish is heritable, it is unknown if inherited traits that support enhanced swimming stamina in offspring appear only in juveniles and/or adults, or if these traits actually appear earlier in the morphologically quite different larvae. To answer this question, mature adult zebrafish (Danio rerio were subjected to a swimming performance test that allowed separation into low swimming stamina or high swimming stamina groups. Adults were then bred within their own performance groups. Larval offspring from each of the two groups, designated high (LHSD and low stamina-derived larvae (LLSD, were then reared at 27°C in aerated water (21% O2. Routine (fH,r and active (fH,a heart rate, and routine (M.O2,r and active (M.O2,a mass-specific oxygen consumption were recorded from 5 days post fertilization (dpf through 21 dpf, and gross cost of transport and factorial aerobic metabolic scope were derived from M.O2 measurements. Heart rate generally ranged between 150 and 225 b•min-1 in both LHSD and LLSD populations. However, significant (P<0.05 differences existed between the LLSD and LHSD populations at 5 and 14 dpf in fH,r and at days 10 and 15 dpf in fH,a. M.O2,r was 0.04 to 0.32 μmol•mg-1•hr-1, while M.O2,a was 0.2 to 1.2 μmol•mg-1•hr-1. Significant (P<0.05 differences between the LLSD and LHSD populations in M.O2,r occurred at 7, 10 and 21 dpf and in M.O2,a at 7 dpf. Gross cost of transport was ~6-10 µmol O2 . µg-1 . m-1 at 5 dpf, peaking at 14-19 µmol O2 . µg-1 . m-1 at 7-10 dpf, before falling again to 5-6 µmol O2 . µg-1 . m-1 at 21 dpf, with gross cost of transport significantly higher in the LLSD population at 7 dpf. Collectively, these data indicate that inherited physiological differences contributing to enhanced stamina in adult parents appear in their larval offspring well before attainment of juvenile or adult features.

  17. Assessment of multiple hormone activities of a UV-filter (octocrylene) in zebrafish (Danio rerio).

    Science.gov (United States)

    Zhang, Qiuya Y; Ma, Xiaoyan Y; Wang, Xiaochang C; Ngo, Huu Hao

    2016-09-01

    In this study, zebrafish (Danio rerio) were exposed to a UV-filter-octocrylene (OCT) with elevated concentrations for 28 d. The total body accumulation of OCT in zebrafish was found to reach 2321.01 ("L" level), 31,234.80 ("M" level), and 70,593.38 ng g(-1) ("H" level) when the average OCT exposure concentration was controlled at 28.61, 505.62, and 1248.70 μg L(-1), respectively. Gross and histological observations as well as RT-qPCR analysis were conducted to determine the effects of OCT accumulation on zebrafish. After exposure, the gonad-somatic index and percentage of vitellogenic oocytes were found to increase significantly in the ovaries of female zebrafish at the H accumulation level. Significant up-regulation of esr1 and cyp19b were observed in the gonads, as well as vtg1 in the livers for both female and male zebrafish. At M and H accumulation levels, apparent down-regulation of ar was observed in the ovaries and testis of the female and male zebrafish, respectively. Although the extent of the effects on zebrafish differed at different accumulation levels, the induction of vtg1 and histological changes in the ovaries are indications of estrogenic activity and the inhibition of esr1 and ar showed antiestrogenic and antiandrogenic activity, respectively. Thus, as OCT could easily accumulate in aquatic life such as zebrafish, one of its most of concern hazards would be the disturbance of the histological development and its multiple hormonal activities. PMID:27337435

  18. Automated visual choice discrimination learning in zebrafish (Danio rerio)

    OpenAIRE

    Mueller, Kaspar P.; Neuhauss, Stephan C. F.

    2012-01-01

    Training experimental animals to discriminate between different visual stimuli has been an important tool in cognitive neuroscience as well as in vision research for many decades. Current methods used for visual choice discrimination training of zebrafish require human observers for response tracking, stimulus presentation and reward delivery and, consequently, are very labor intensive and possibly experimenter biased. By combining video tracking of fish positions, stimulus presentation on co...

  19. Zinc transporter expression in zebrafish (Danio rerio) during development☆

    OpenAIRE

    Ho, Emily; Dukovcic, Stephanie; Hobson, Brad; Wong, Carmen P.; Miller, Galen; Hardin, Karin; TRABER, MARET G.; Tanguay, Robert L.

    2011-01-01

    Zinc is a micronutrient important in several biological processes including growth and development. We have limited knowledge on the impact of maternal zinc deficiency on zinc and zinc regulatory mechanisms in the developing embryo due to a lack of in vivo experimental models that allow us to directly study the effects of maternal zinc on embryonic development following implantation. To overcome this barrier, we have proposed to use zebrafish as a model organism to study the impact of zinc du...

  20. Oscillations in shoal cohesion in zebrafish (Danio rerio)

    OpenAIRE

    Miller, Noam Y.; Gerlai, Robert

    2008-01-01

    In many species, group cohesion may be the result of a compromise between opposing forces (e.g. predator avoidance and competition for food). However, little empirical data exists on the dynamics of group cohesion. We present moment-to-moment positional data on zebrafish shoals and analyze temporal changes in inter-individual distances. We demonstrate that the distance between shoal members does not settle at any given value, as has previously been assumed, but oscillates with a period betwee...

  1. Ingestion of metal-nanoparticle contaminated food disrupts endogenous microbiota in zebrafish (Danio rerio)

    International Nuclear Information System (INIS)

    Nanoparticles (NPs) can be ingested by organisms, and NPs with antimicrobial properties may disrupt beneficial endogenous microbial communities and affect organism health. Zebrafish were fed diets containing Cu-NPs or Ag-NPs (500 mg kg−1 food), or an appropriate control for 14 d. Intestinal epithelium integrity was examined by transmission electron microscopy, and microbial community structure within the intestine was assessed by denaturing gradient gel electrophoresis (DGGE) of partial 16S rRNA. No lesions were observed in intestinal epithelia; however, presence of NPs in diets changed intestinal microbial community structure. In particular, some beneficial bacterial strains (e.g., Cetobacterium somerae) were suppressed to non-detectable levels by Cu-NP exposure, and two unidentified bacterial clones from the Firmicutes phylum were sensitive (not detected) to Cu, but were present in Ag and control fish. Unique changes in zebrafish microbiome caused by exposure to Ag-NP and Cu-NP indicate that NP ingestion could affect digestive system function and organism health. -- Highlights: ► Zebrafish ingest Cu- and Ag-nanoparticles (NPs) in diet. ► No effect of Cu-NPs or Ag-NPs on intestinal epithelial integrity. ► Cu-NPs and Ag-NPs alter endogenous microbiota of zebrafish. -- Dietary exposure to manufactured Cu- and Ag-nanoparticles caused unique changes in endogenous gut microbiota in zebrafish Danio rerio

  2. Alcohol-induced morphological deficits in the development of octavolateral organs of the zebrafish (Danio rerio).

    Science.gov (United States)

    Zamora, Lilliann Y; Lu, Zhongmin

    2013-03-01

    Prenatal alcohol exposure is known to have many profound detrimental effects on human fetal development (fetal alcohol spectrum disorders), which may manifest as lifelong disabilities. However, how alcohol affects the auditory/vestibular system is still largely unknown. This is the first study to investigate morphological effects of alcohol on the developing octavolateral system (the inner ear and lateral line) using the zebrafish, Danio rerio. Zebrafish embryos of 2 hours post fertilization (hpf) were treated in 2% alcohol for 48 hours and screened at 72 hpf for morphological defects of the inner ear and lateral line. Octavolateral organs from both alcohol-treated and control zebrafish were examined using light, confocal, and scanning electron microscopy. We observed several otolith phenotypes for alcohol-treated zebrafish including zero, one, two abnormal, two normal, and multiple otoliths. Results of this study show that alcohol treatment during early development impairs the inner ear (smaller ear, abnormal otoliths, and fewer sensory hair cells) and the lateral line (smaller neuromasts, fewer neuromasts and hair cells per neuromast, and shorter kinocilia of hair cells). Early embryonic alcohol exposure may also result in defects in hearing, balance, and hydrodynamic function of zebrafish.

  3. From schooling to shoaling: patterns of collective motion in zebrafish (Danio rerio.

    Directory of Open Access Journals (Sweden)

    Noam Miller

    Full Text Available Animal groups on the move can take different configurations. For example, groups of fish can either be 'shoals' or 'schools': shoals are simply aggregations of individuals; schools are shoals exhibiting polarized, synchronized motion. Here we demonstrate that polarization distributions of groups of zebrafish (Danio rerio are bimodal, showing two distinct modes of collective motion corresponding to the definitions of shoaling and schooling. Other features of the group's motion also vary consistently between the two modes: zebrafish schools are faster and less dense than zebrafish shoals. Habituation to an environment can also alter the proportion of time zebrafish groups spend schooling or shoaling. Models of collective motion suggest that the degree and stability of group polarization increases with the group's density. Examining zebrafish groups of different sizes from 5 to 50, we show that larger groups are less polarized than smaller groups. Decreased fearfulness in larger groups may function similarly to habituation, causing them to spend more time shoaling than schooling, contrary to most models' predictions.

  4. Effect of water hardness on peracetic acid toxicity to zebrafish, Danio rerio, embryos

    DEFF Research Database (Denmark)

    Marchand, Pierre_André; Strauss, David L.; Wienke, Andreas;

    2013-01-01

    products to embryos of zebrafish (Danio rerio). Embryos were exposed to PAA ranging from 0 to 9 mg/L in low-hardness (1.4 dH or 25 mg/L hardness as CaCO3), medium-hardness (14 dH or 250 mg/L hardness as CaCO3) and high-hardness (140 dH or 2,500 mg/L hardness as CaCO3) waters. The lowest LC50 value was 2...

  5. In Vivo Toxicity of Silver Nanoparticles and Silver Ions in Zebrafish (Danio rerio)

    OpenAIRE

    Bilberg, Katrine; Hovgaard, Mads Bruun; Besenbacher, Flemming; Baatrup, Erik

    2011-01-01

    The influence of water chemistry on characterised polyvinyl pyrrolidone- (PVP-) coated silver nanoparticles (81 nm) was investigated. NaCl solution series of 100–800 mg L−1 lead to initial and temporal increase in nanoparticles size, but agglomeration was limited. pH variation (5–8) had only minor influence on the hydrodynamic particle size. Acute toxicity of nanosivler to zebrafish (Danio rerio) was investigated in a 48-hour static renewal study and compared with the toxicity of silver ions ...

  6. In Vivo Toxicity of Silver Nanoparticles and Silver Ions in Zebrafish (Danio rerio)

    OpenAIRE

    Katrine Bilberg; Mads Bruun Hovgaard; Flemming Besenbacher; Erik Baatrup

    2012-01-01

    The influence of water chemistry on characterised polyvinyl pyrrolidone- (PVP-) coated silver nanoparticles (81 nm) was investigated. NaCl solution series of 100–800 mg L−1 lead to initial and temporal increase in nanoparticles size, but agglomeration was limited. pH variation (5–8) had only minor influence on the hydrodynamic particle size. Acute toxicity of nanosivler to zebrafish (Danio rerio) was investigated in a 48-hour static renewal study and compared with the toxicity of silver ions ...

  7. Molecular cloning and functional analysis of zebrafish (Danio rerio) chemokine genes.

    Science.gov (United States)

    Chen, Li-Chen; Chen, Jyh-Yih; Hour, Ai-Ling; Shiau, Chyuan-Yuan; Hui, Cho-Fat; Wu, Jen-Leih

    2008-12-01

    Chemokines control leukocyte trafficking which plays important roles in resistance to pathogenic infection. Five CXC chemokines have been reported in the zebrafish (Danio rerio) in GenBank, and herein we named them CXC-46, -56, -64, -66, and scyba. Through RT-PCR for cloning and sequencing these chemokines, the cDNA sequences of CXC-46, -56, -64, and -66 of zebrafish were determined, and it was found that the cDNA sequences were the same as those published in GenBank. Phylogenetic analysis revealed that zebrafish scyba is closest to the CXCL14 subgroup, CXC-46 is closest to the human CCL25 and catfish CXCL-2-like gene, and CXC-56, -64, and -66 are closest to the catfish CXCL10 subgroup. Further study of the tissue-specific, lipopolysaccharide (LPS) stimulation-specific, and polyinosinic-polycytidylic acid (poly I:C) stimulation-specific expressions of these five zebrafish CXC chemokine messenger (m)RNAs were determined by a comparative reverse-transcription polymerase chain reaction (RT-PCR). The RT-PCR revealed a high level of constitutive expression of CXC-56 in many tissues including the eyes, fins, heart, liver, muscles, and skin. Starvation had significant effects on the gene expressions of several zebrafish CXC chemokines including CXC-56, -64, -66, and scyba compared to the control group. Zebrafish CXC chemokines showed a concave pattern of expression after stimulation with LPS. Following poly I:C treatment of between 0.1 and 10 g/fish, dose-dependent effects were revealed. Temperature and acid-base conditions affected these zebrafish chemokines by increasing their induction compared to the control group, except for CXC-64 which exhibited no significant differences in either condition. Furthermore, these novel research results indicate that chemokines can be markers of different experimental conditions. PMID:18778789

  8. Real-world carbon nanoparticle exposures induce brain and gonadal alterations in zebrafish (Danio rerio) as determined by biospectroscopy techniques

    OpenAIRE

    Li, Junyi; Ying, Guang-Guo; Jones, Kevin C.; Martin, Francis L.

    2015-01-01

    Carbon-based nanoparticles (CNPs) have emerged as novel man-made materials with diverse applications, which may present significant risks to organisms. To bridge the gap in our knowledge of nano-toxicology, a number of in vitro or in vivo studies have been carried out. However, toxicity data remains limited. Herein, we employed a biospectroscopy approach to assess CNP-induced effects in zebrafish (Danio rerio). Zebrafish were exposed to Fullerene (C60), long or short multi-walled carbon nanot...

  9. Genetic analysis of male reproductive success in relation to density in the zebrafish, Danio rerio

    Directory of Open Access Journals (Sweden)

    Jordan William C

    2006-04-01

    Full Text Available Abstract Background We used behavioural and genetic data to investigate the effects of density on male reproductive success in the zebrafish, Danio rerio. Based on previous measurements of aggression and courtship behaviour by territorial males, we predicted that they would sire more offspring than non-territorial males. Results Microsatellite analysis of paternity showed that at low densities territorial males had higher reproductive success than non-territorial males. However, at high density territorial males were no more successful than non-territorials and the sex difference in the opportunity for sexual selection, based on the parameter Imates, was low. Conclusion Male zebrafish exhibit two distinct mating tactics; territoriality and active pursuit of females. Male reproductive success is density dependent and the opportunity for sexual selection appears to be weak in this species.

  10. Influence of kinship and MHC class II genotype on visual traits in zebrafish larvae (Danio rerio).

    Science.gov (United States)

    Hinz, Cornelia; Gebhardt, Katharina; Hartmann, Alexander K; Sigman, Lauren; Gerlach, Gabriele

    2012-01-01

    Kin recognition can drive kin selection and the evolution of social behaviour. In zebrafish (Danio rerio, Hamilton 1822), kin recognition is based on olfactory and visual imprinting processes. If larvae are exposed to visual and chemical cues of kin at day 5 and 6 post fertilization they will recognize kin throughout life, while exposure to non-kin fails to trigger any recognition. Chemical imprinting signals are transcribed by polymorphic genes of the major histocompatibility complex (MHC) code; however, the underlying mechanism for visual imprinting remains unclear. Here we provide evidence for the existence of family-specific differences in morphometry and pigmentation pattern of six day old zebrafish larvae. While rump, tail and body pigmentation were dependent on relatedness, iris pigmentation and morphometry were also influenced by MHC class II genotype. Our study revealed that the MHC not only influences the chemical signature of individuals, but also their visual appearance. PMID:23251449

  11. Cortactin mediated morphogenic cell movements during zebrafish (Danio rerio) gastrulation

    Institute of Scientific and Technical Information of China (English)

    YU Dan; ZHANG Peijun; ZHAN Xi

    2005-01-01

    Cell migration is essential to direct embryonic cells to specific sites at which their developmental fates are ultimately determined. However, the mechanism by which cell motility is regulated in embryonic development is largely unknown. Cortactin, a filamentous actin binding protein, is an activator of Arp2/3 complex in the nucleation of actin cytoskeleton at the cell leading edge and acts directly on the machinery of cell motility. To determine whether cortactin and Arp2/3 mediated actin assembly plays a role in the morphogenic cell movements during the early development of zebrafish, we initiated a study of cortactin expression in zebrafish embryos at gastrulating stages when massive cell migrations occur. Western blot analysis using a cortactin specific monoclonal antibody demonstrated that cortactin protein is abundantly present in embryos at the most early developmental stages. Immunostaining of whole-mounted embryo showed that cortactin immunoreactivity was associated with the embryonic shield, predominantly at the dorsal side of the embryos during gastrulation. In addition, cortactin was detected in the convergent cells of the epiblast and hypoblast, and later in the central nervous system. Immunofluorescent staining with cortactin and Arp3 antibodies also revealed that cortactin and Arp2/3 complex colocalized at the periphery and many patches associated with the cell-to-cell junction in motile embryonic cells. Therefore, our data suggest that cortactin and Arp2/3 mediated actin polymerization is implicated in the cell movement during gastrulation and perhaps the development of the central neural system as well.

  12. Effects of uranium on the metabolism of zebrafish, Danio rerio

    Energy Technology Data Exchange (ETDEWEB)

    Augustine, Starrlight, E-mail: starr-light.augustine@irsn.fr [Laboratory of Radionuclide Ecotoxicology, PRP-ENV/SERIS/LECO, Institute of Radioprotection and Nuclear Safety (IRSN), Caradache, Building 186, BP3, 13115 St-Paul-lez-Durance Cedex (France); Gagnaire, Beatrice, E-mail: beatrice.gagnaire@irsn.fr [Laboratory of Radionuclide Ecotoxicology, PRP-ENV/SERIS/LECO, Institute of Radioprotection and Nuclear Safety (IRSN), Caradache, Building 186, BP3, 13115 St-Paul-lez-Durance Cedex (France); Adam-Guillermin, Christelle, E-mail: christelle.adam-guillermin@irsn.fr [Laboratory of Radionuclide Ecotoxicology, PRP-ENV/SERIS/LECO, Institute of Radioprotection and Nuclear Safety (IRSN), Caradache, Building 186, BP3, 13115 St-Paul-lez-Durance Cedex (France); Kooijman, Sebastiaan A.L.M., E-mail: bas.kooijman@vu.nl [Department of Theoretical Biology, Vrije Universiteit, de Boelelaan 1087, 1081 HV Amsterdam (Netherlands)

    2012-08-15

    The increasing demand for nuclear energy results in heightened levels of uranium (U) in aquatic systems which present a potential health hazard to resident organisms. The aim of this study was to mechanistically assess how chronic exposure to environmentally relevant concentrations of U perturbs the complex interplay between feeding, growth, maintenance, maturation and reproduction throughout the life-cycle of an individual. To this end we analysed literature-based and original zebrafish toxicity data within a same mass and energy balancing conceptual framework. U was found to increase somatic maintenance leading to inhibition of spawning as well as increase hazard rate and costs for growth during the early life stages. The fish's initial conditions and elimination through reproduction greatly affected toxico-kinetics and effects. We demonstrate that growth and reproduction should be measured on specific individuals since mean values were hardly interpretable. The mean food level differed between experiments, conditions and individuals. This last 'detail' contributed substantially to the observed variability by its combined effect on metabolism, toxic effects and toxico-kinetics. The significance of this work is that we address exactly how these issues are related and derive conclusions which are independent of experimental protocol and coherent with a very large body of literature on zebrafish eco-physiology.

  13. Effects of uranium on the metabolism of zebrafish, Danio rerio

    International Nuclear Information System (INIS)

    The increasing demand for nuclear energy results in heightened levels of uranium (U) in aquatic systems which present a potential health hazard to resident organisms. The aim of this study was to mechanistically assess how chronic exposure to environmentally relevant concentrations of U perturbs the complex interplay between feeding, growth, maintenance, maturation and reproduction throughout the life-cycle of an individual. To this end we analysed literature-based and original zebrafish toxicity data within a same mass and energy balancing conceptual framework. U was found to increase somatic maintenance leading to inhibition of spawning as well as increase hazard rate and costs for growth during the early life stages. The fish's initial conditions and elimination through reproduction greatly affected toxico-kinetics and effects. We demonstrate that growth and reproduction should be measured on specific individuals since mean values were hardly interpretable. The mean food level differed between experiments, conditions and individuals. This last ‘detail’ contributed substantially to the observed variability by its combined effect on metabolism, toxic effects and toxico-kinetics. The significance of this work is that we address exactly how these issues are related and derive conclusions which are independent of experimental protocol and coherent with a very large body of literature on zebrafish eco-physiology.

  14. Long-term effects of a binary mixture of perfluorooctane sulfonate (PFOS) and bisphenol A (BPA) in zebrafish (Danio rerio)

    DEFF Research Database (Denmark)

    Keiter, Susanne; Baumann, Lisa; Farber, H;

    2012-01-01

    aimed at evaluating the long-term effects and toxicity-increasing behavior of PFOS in vivo using the zebrafish (Danio rerio). Fish were maintained in flow-through conditions and exposed to single and binary mixtures of PFOS and the endocrine disruptor bisphenol A (BPA) at nominal concentrations of 0...

  15. Divergent teratogenicity of agonists of retinoid X receptors in embryos of zebrafish (Danio rerio).

    Science.gov (United States)

    Shi, Huahong; Zhu, Pan; Sun, Zhi; Yang, Bo; Zheng, Liang

    2012-07-01

    Zebrafish (Danio rerio) embryos were comparably exposed to seven known agonists of retinoid X receptors (RXRs) including two endogenous compounds (9-cis-retinoic acid and docosahexaenoic acid), four man-made selective ligands (LGD1069, SR11237, fluorobexarotene and CD3254), and a biocide (triphenyltin). The dominant phenotypes of malformation were sharp mouths and small caudal fins in 1 mg/L SR11237-treated group after 5 days exposure. 9-cis-retinoic acid and LGD1069 induced multiple malformations including small eyes, bent notochords, reduced brain, enlarged proctodaems, absence of fins, short tails and edema after 5 days exposure. Fluorobexarotene and CD3254 induced similar phenotypes of malformations after 5 days exposure at low concentration (20 μg/L) to those after the 1st d exposure at high concentrations (50 and 100 μg/L). Triphenlytin induced multiple malformations including deformed eyes, bent notochords, bent tails, and edema in hearts after 5 days exposure at concentrations of 1-10 μg Sn/L. In contrast, no discernible malformations were observed in triphenlytin-treated groups after each separate day exposure. These agonists not only showed different ability of teratogenicity but also induced different phenotypes of malformation in zebrafish embryos. In addition, the sensitive stages of zebrafish embryos were different in response to these agonists. Therefore, our results suggest that the agonists of RXRs had divergent teratogenicity in zebrafish embryos. PMID:22526925

  16. Cold acclimation alters the connective tissue content of the zebrafish (Danio rerio) heart.

    Science.gov (United States)

    Johnson, Amy C; Turko, Andy J; Klaiman, Jordan M; Johnston, Elizabeth F; Gillis, Todd E

    2014-06-01

    Thermal acclimation can alter cardiac function and morphology in a number of fish species, but little is known about the regulation of these changes. The purpose of the present study was to determine how cold acclimation affects zebrafish (Danio rerio) cardiac morphology, collagen composition and connective tissue regulation. Heart volume, the thickness of the compact myocardium, collagen content and collagen fiber composition were compared between control (27°C) and cold-acclimated (20°C) zebrafish using serially sectioned hearts stained with Picrosirius Red. Collagen content and fiber composition of the pericardial membrane were also examined. Cold acclimation did not affect the volume of the contracted heart; however, there was a significant decrease in the thickness of the compact myocardium. There was also a decrease in the collagen content of the compact myocardium and in the amount of thick collagen fibers throughout the heart. Cold-acclimated zebrafish also increased expression of the gene transcript for matrix metalloproteinase 2, matrix metalloproteinase 9, tissue inhibitor of metalloproteinase 2 and collagen Type I α1. We propose that the reduction in the thickness of the compact myocardium as well as the change in collagen content may help to maintain the compliance of the ventricle as temperatures decrease. Together, these results clearly demonstrate that the zebrafish heart undergoes significant remodeling in response to cold acclimation. PMID:24577447

  17. Genes involved in forebrain development in the zebrafish, Danio rerio.

    Science.gov (United States)

    Heisenberg, C P; Brand, M; Jiang, Y J; Warga, R M; Beuchle, D; van Eeden, F J; Furutani-Seiki, M; Granato, M; Haffter, P; Hammerschmidt, M; Kane, D A; Kelsh, R N; Mullins, M C; Odenthal, J; Nusslein-Volhard, C

    1996-12-01

    We identified four zebrafish mutants with defects in forebrain induction and patterning during embryogenesis. The four mutants define three genes: masterblind (mbl), silberblick (slb), and knollnase (kas). In mbl embryos, the anterior forebrain acquires posterior forebrain characteristics: anterior structures such as the eyes, olfactory placodes and the telencephalon are missing, whereas the epiphysis located in the posterior forebrain is expanded. In slb embryos, the extension of the embryonic axis is initially delayed and eventually followed by a partial fusion of the eyes. Finally, in kas embryos, separation of the telencephalic primordia is incomplete and dorsal midline cells fail to form a differentiated roof plate. Analysis of the mutant phenotypes indicates that we have identified genes essential for the specification of the anterior forebrain (mbl), positioning of the eyes (slb) and differentiation of the roof plate (kas). In an appendix to this study we list mutants showing alterations in the size of the eyes and abnormal differentiation of the lenses. PMID:9007240

  18. Developmental mechanisms of arsenite toxicity in zebrafish (Danio rerio) embryos

    Energy Technology Data Exchange (ETDEWEB)

    Li Dan [Department of Genetics, National Research Institute for Family Planning, Beijing (China); Graduate School of Peking Union Medical College, Beijing (China); Lu Cailing [Department of Genetics, National Research Institute for Family Planning, Beijing (China); Wang Ju; Hu Wei; Cao Zongfu; Sun Daguang [Department of Genetics, National Research Institute for Family Planning, Beijing (China); Graduate School of Peking Union Medical College, Beijing (China); Xia Hongfei [Department of Genetics, National Research Institute for Family Planning, Beijing (China); Ma Xu [Department of Genetics, National Research Institute for Family Planning, Beijing (China) and Graduate School of Peking Union Medical College, Beijing (China) and Department of Reproductive Genetics, WHO Collaborative Center for Research in Human Reproduction, Beijing (China)], E-mail: genetic@263.net.cn

    2009-02-19

    Arsenic usually accumulates in soil, water and airborne particles, from which it is taken up by various organisms. Exposure to arsenic through food and drinking water is a major public health problem affecting some countries. At present there are limited laboratory data on the effects of arsenic exposure on early embryonic development and the mechanisms behind its toxicity. In this study, we used zebrafish as a model system to investigate the effects of arsenite on early development. Zebrafish embryos were exposed to a range of sodium arsenite concentrations (0-10.0 mM) between 4 and 120 h post-fertilization (hpf). Survival and early development of the embryos were not obviously influenced by arsenite concentrations below 0.5 mM. However, embryos exposed to higher concentrations (0.5-10.0 mM) displayed reduced survival and abnormal development including delayed hatching, retarded growth and changed morphology. Alterations in neural development included weak tactile responses to light (2.0-5.0 mM, 30 hpf), malformation of the spinal cord and disordered motor axon projections (2.0 mM, 48 hpf). Abnormal cardiac function was observed as bradycardia (0.5-2.0 mM, 60 hpf) and altered ventricular shape (2.0 mM, 48 hpf). Furthermore, altered cell proliferation (2.0 mM, 24 hpf) and apoptosis status (2.0 mM, 24 and 48 hpf), as well as abnormal genomic DNA methylation patterning (2.0 mM, 24 and 48 hpf) were detected in the arsenite-treated embryos. All of these indicate a possible relationship between arsenic exposure and developmental failure in early embryogenesis. Our studies suggest that the negative effects of arsenic on vertebrate embryogenesis are substantial.

  19. A proteome map of the zebrafish (Danio rerio) lens reveals similarities between zebrafish and mammalian crystallin expression

    OpenAIRE

    Posner, Mason; Hawke, Molly; LaCava, Carrie; Prince, Courtney J.; Bellanco, Nicholas R.; Corbin, Rebecca W.

    2008-01-01

    Purpose To characterize the crystallin content of the zebrafish lens using two-dimensional gel electrophoresis (2-DE). These data will facilitate future investigations of vertebrate lens development, function, and disease. Methods Adult zebrafish lens proteins were separated by 2-DE, and the resulting spots were identified by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS). The relative proportion of each crystallin was quantified by image analysis,...

  20. Calsequestrins in skeletal and cardiac muscle from adult Danio rerio.

    Science.gov (United States)

    Furlan, Sandra; Mosole, Simone; Murgia, Marta; Nagaraj, Nagarjuna; Argenton, Francesco; Volpe, Pompeo; Nori, Alessandra

    2016-04-01

    Calsequestrin (Casq) is a high capacity, low affinity Ca(2+)-binding protein, critical for Ca(2+)-buffering in cardiac and skeletal muscle sarcoplasmic reticulum. All vertebrates have multiple genes encoding for different Casq isoforms. Increasing interest has been focused on mammalian and human Casq genes since mutations of both cardiac (Casq2) and skeletal muscle (Casq1) isoforms cause different, and sometime severe, human pathologies. Danio rerio (zebrafish) is a powerful model for studying function and mutations of human proteins. In this work, expression, biochemical properties cellular and sub-cellular localization of D. rerio native Casq isoforms are investigated. By quantitative PCR, three mRNAs were detected in skeletal muscle and heart with different abundances. Three zebrafish Casqs: Casq1a, Casq1b and Casq2 were identified by mass spectrometry (Data are available via ProteomeXchange with identifier PXD002455). Skeletal and cardiac zebrafish calsequestrins share properties with mammalian Casq1 and Casq2. Skeletal Casqs were found primarily, but not exclusively, at the sarcomere Z-line level where terminal cisternae of sarcoplasmic reticulum are located. PMID:26585961

  1. Transcriptional regulatory dynamics of the hypothalamic-pituitary-gonadal axis and its peripheral pathways as impacted by the 3-beta HSD inhibitor Trilostane in zebrafish (Danio rerio)

    Science.gov (United States)

    To identify transcription factors (TFs), members of hypothalamic-pituitary- gonadal axis (HPG-axis), TF networks and signaling pathways underlying generalized effects of 3-beta hydroxysteroid dehydrogenase (HSD3B) inhibition, reproductively mature zebrafish (Danio rerio) were exp...

  2. Primary neuron culture for nerve growth and axon guidance studies in zebrafish (Danio rerio.

    Directory of Open Access Journals (Sweden)

    Zheyan Chen

    Full Text Available Zebrafish (Danio rerio is a widely used model organism in genetics and developmental biology research. Genetic screens have proven useful for studying embryonic development of the nervous system in vivo, but in vitro studies utilizing zebrafish have been limited. Here, we introduce a robust zebrafish primary neuron culture system for functional nerve growth and guidance assays. Distinct classes of central nervous system neurons from the spinal cord, hindbrain, forebrain, and retina from wild type zebrafish, and fluorescent motor neurons from transgenic reporter zebrafish lines, were dissociated and plated onto various biological and synthetic substrates to optimize conditions for axon outgrowth. Time-lapse microscopy revealed dynamically moving growth cones at the tips of extending axons. The mean rate of axon extension in vitro was 21.4±1.2 µm hr(-1 s.e.m. for spinal cord neurons, which corresponds to the typical ∼0.5 mm day(-1 growth rate of nerves in vivo. Fluorescence labeling and confocal microscopy demonstrated that bundled microtubules project along axons to the growth cone central domain, with filamentous actin enriched in the growth cone peripheral domain. Importantly, the growth cone surface membrane expresses receptors for chemotropic factors, as detected by immunofluorescence microscopy. Live-cell functional assays of axon extension and directional guidance demonstrated mammalian brain-derived neurotrophic factor (BDNF-dependent stimulation of outgrowth and growth cone chemoattraction, whereas mammalian myelin-associated glycoprotein inhibited outgrowth. High-resolution live-cell Ca(2+-imaging revealed local elevation of cytoplasmic Ca(2+ concentration in the growth cone induced by BDNF application. Moreover, BDNF-induced axon outgrowth, but not basal outgrowth, was blocked by treatments to suppress cytoplasmic Ca(2+ signals. Thus, this primary neuron culture model system may be useful for studies of neuronal development

  3. Gene expression profiling of the androgen receptor antagonists flutamide and vinclozolin in zebrafish (Danio rerio) gonads

    International Nuclear Information System (INIS)

    The studies presented in this manuscript focus on characterization of transcriptomic responses to anti-androgens in zebrafish (Danio rerio). Research on the effects of anti-androgens in fish has been characterized by a heavy reliance on apical endpoints, and molecular mechanisms of action (MOA) of anti-androgens remain poorly elucidated. In the present study, we examined effects of a short term exposure (24-96 h) to the androgen receptor antagonists flutamide (FLU) and vinclozolin (VZ) on gene expression in gonads of sexually mature zebrafish, using commercially available zebrafish oligonucleotide microarrays (4 x 44 K platform). We found that VZ and FLU potentially impact reproductive processes via multiple pathways related to steroidogenesis, spermatogenesis, and fertilization. Observed changes in gene expression often were shared by VZ and FLU, as demonstrated by overlap in differentially-expressed genes and enrichment of several common key pathways including: (1) integrin and actin signaling, (2) nuclear receptor 5A1 signaling, (3) fibroblast growth factor receptor signaling, (4) polyamine synthesis, and (5) androgen synthesis. This information should prove useful to elucidating specific mechanisms of reproductive effects of anti-androgens in fish, as well as developing biomarkers for this important class of endocrine-active chemicals.

  4. Effects of base analogues 5-bromouracil and 6-aminopurine on development of zebrafish Danio Rerio

    Institute of Scientific and Technical Information of China (English)

    SAWANT M. S.; ZHANG Shicui; WANG Qingyin

    2005-01-01

    Zebrafish (Danio rerio) genetic screens allow isolation of a wide array of problems in vertebrate biology. The effects of base analogues 5-bromouracil and 6-aminopurine on the development of zebrafish embryos are reported for the first time in this study. The early development of the zebrafish embryos was little affected by 5-bromouracil and 6-aminopurine, while the late development (organogenesis) was significantly impaired. Embryos exposed to 5-bromouracil mainly showed curled tail, wavy body, golden pigmentation and the mouth with protruding lower jaw. 6-aminopurine-treated embryos had defective anterior structures, curled tails and wavy body. RAPD analysis showed that the majority of 5-bromouracil- and 6-aminopurine-treated larvae and fish shared banding patterns in common with the control, suggesting that most mutagenesis induced by these agents are point mutations. However, some fish derived from 5-bromouracil-treated embryos had golden (gol) pigmentation; and RAPD analysis revealed that their band patterns differed from those of the control.Possibly, 5-bromouracil can occasionally cause relatively extensive changes in the fish genome. The results of this study may provide valuable help for detailed studies of mutagenesis.

  5. Gene expression profiling of the androgen receptor antagonists flutamide and vinclozolin in zebrafish (Danio rerio) gonads

    Energy Technology Data Exchange (ETDEWEB)

    Martinovic-Weigelt, Dalma, E-mail: dalma@stthomas.edu [US Environmental Protection Agency, Office of Research and Development, National Health and Environmental Effects Research Laboratory, Mid-Continent Ecology Division, 6201 Congdon Blvd., Duluth, MN 55804 (United States); University of St. Thomas, 2115 Summit Ave, Saint Paul, MN 55105 (United States); Wang Ronglin [US Environmental Protection Agency, Office of Research and Development, National Exposure Research Laboratory, Ecological Exposure Research Division, 26W. Martin Luther King Dr., Cincinnati, OH 45268 (United States); Villeneuve, Daniel L. [US Environmental Protection Agency, Office of Research and Development, National Health and Environmental Effects Research Laboratory, Mid-Continent Ecology Division, 6201 Congdon Blvd., Duluth, MN 55804 (United States); Bencic, David C.; Lazorchak, Jim [US Environmental Protection Agency, Office of Research and Development, National Exposure Research Laboratory, Ecological Exposure Research Division, 26W. Martin Luther King Dr., Cincinnati, OH 45268 (United States); Ankley, Gerald T. [US Environmental Protection Agency, Office of Research and Development, National Health and Environmental Effects Research Laboratory, Mid-Continent Ecology Division, 6201 Congdon Blvd., Duluth, MN 55804 (United States)

    2011-01-25

    The studies presented in this manuscript focus on characterization of transcriptomic responses to anti-androgens in zebrafish (Danio rerio). Research on the effects of anti-androgens in fish has been characterized by a heavy reliance on apical endpoints, and molecular mechanisms of action (MOA) of anti-androgens remain poorly elucidated. In the present study, we examined effects of a short term exposure (24-96 h) to the androgen receptor antagonists flutamide (FLU) and vinclozolin (VZ) on gene expression in gonads of sexually mature zebrafish, using commercially available zebrafish oligonucleotide microarrays (4 x 44 K platform). We found that VZ and FLU potentially impact reproductive processes via multiple pathways related to steroidogenesis, spermatogenesis, and fertilization. Observed changes in gene expression often were shared by VZ and FLU, as demonstrated by overlap in differentially-expressed genes and enrichment of several common key pathways including: (1) integrin and actin signaling, (2) nuclear receptor 5A1 signaling, (3) fibroblast growth factor receptor signaling, (4) polyamine synthesis, and (5) androgen synthesis. This information should prove useful to elucidating specific mechanisms of reproductive effects of anti-androgens in fish, as well as developing biomarkers for this important class of endocrine-active chemicals.

  6. Genetic variation in strains of zebrafish (Danio rerio) and the implications for ecotoxicology studies.

    Science.gov (United States)

    Coe, T S; Hamilton, P B; Griffiths, A M; Hodgson, D J; Wahab, M A; Tyler, C R

    2009-01-01

    There is substantial evidence that genetic variation, at both the level of the individual and population, has a significant effect on behaviour, fitness and response to toxicants. Using DNA microsatellites, we examined the genetic variation in samples of several commonly used laboratory strains of zebrafish, Danio rerio, a model species in toxicological studies. We compared the genetic variation to that found in a sample of wild fish from Bangladesh. Our findings show that the wild fish were significantly more variable than the laboratory strains for several measures of genetic variability, including allelic richness and expected heterozygosity. This lack of variation should be given due consideration for any study which attempts to extrapolate the results of ecotoxicological laboratory tests to wild populations.

  7. Presenilin1 regulates histamine neuron development and behavior in zebrafish, danio rerio.

    Science.gov (United States)

    Sundvik, Maria; Chen, Yu-Chia; Panula, Pertti

    2013-01-23

    Modulatory neurotransmitters, including the histaminergic system, are essential in mediating cognitive functions affected in Alzheimer's disease (AD). The roles of disease genes associated with AD, most importantly the presenilin1 gene (psen1), are poorly understood. We studied the role of psen1 in plasticity of the brain histaminergic system using a novel psen1 mutant zebrafish, Danio rerio. We found that in psen1(-/-) zebrafish, the histaminergic system is altered throughout life. At 7 d postfertilization (dpf) the histamine neuron number was reduced in psen1(-/-) compared with wild-type (WT) fish; at 2 months of age the histamine neuron number was at the same level as that in WT fish. In 1-year-old zebrafish, the histamine neuron number was significantly increased in psen1(-/-) fish compared with WT fish. These changes in histamine neuron number were accompanied by changes in histamine-driven behaviors. Treatment with DAPT, a γ-secretase inhibitor, similarly interfered with the development of the histaminergic neurons. We also assessed the expression of γ-secretase-regulated Notch1a mRNA and β-catenin at different time points. Notch1a mRNA level was reduced in psen1(-/-) compared with WT fish, whereas β-catenin was slightly upregulated in the hypothalamus of psen1(-/-) compared with WT fish at 7 dpf. The results reveal a life-long brain plasticity in both the structure of the histaminergic system and its functions induced by altered Notch1a activity as a consequence of psen1 mutation. The new histaminergic neurons in aging zebrafish brain may arise as a result of phenotypic plasticity or represent newly differentiated stem cells.

  8. In Vivo Toxicity of Silver Nanoparticles and Silver Ions in Zebrafish (Danio rerio).

    Science.gov (United States)

    Bilberg, Katrine; Hovgaard, Mads Bruun; Besenbacher, Flemming; Baatrup, Erik

    2012-01-01

    The influence of water chemistry on characterised polyvinyl pyrrolidone- (PVP-) coated silver nanoparticles (81 nm) was investigated. NaCl solution series of 100-800 mg L(-1) lead to initial and temporal increase in nanoparticles size, but agglomeration was limited. pH variation (5-8) had only minor influence on the hydrodynamic particle size. Acute toxicity of nanosivler to zebrafish (Danio rerio) was investigated in a 48-hour static renewal study and compared with the toxicity of silver ions (AgNO(3)). The nanosilver and silver ion 48-hour median lethal concentration (LC(50)) values were 84 μg L(-1) and 25 μg L(-1), respectively. To investigate exposure-related stress, the fish behaviour was observed visually after 0, 3, 6, 12, 24, 27, 30, and 48 hours of both nanosilver and ionic silver treatments. These observations revealed increased rate of operculum movement and surface respiration after nanosilver exposure, suggesting respiratory toxicity. The present study demonstrates that silver nanoparticles are lethal to zebrafish.

  9. In Vivo Toxicity of Silver Nanoparticles and Silver Ions in Zebrafish (Danio rerio)

    Science.gov (United States)

    Bilberg, Katrine; Hovgaard, Mads Bruun; Besenbacher, Flemming; Baatrup, Erik

    2012-01-01

    The influence of water chemistry on characterised polyvinyl pyrrolidone- (PVP-) coated silver nanoparticles (81 nm) was investigated. NaCl solution series of 100–800 mg L−1 lead to initial and temporal increase in nanoparticles size, but agglomeration was limited. pH variation (5–8) had only minor influence on the hydrodynamic particle size. Acute toxicity of nanosivler to zebrafish (Danio rerio) was investigated in a 48-hour static renewal study and compared with the toxicity of silver ions (AgNO3). The nanosilver and silver ion 48-hour median lethal concentration (LC50) values were 84 μg L−1 and 25 μg L−1, respectively. To investigate exposure-related stress, the fish behaviour was observed visually after 0, 3, 6, 12, 24, 27, 30, and 48 hours of both nanosilver and ionic silver treatments. These observations revealed increased rate of operculum movement and surface respiration after nanosilver exposure, suggesting respiratory toxicity. The present study demonstrates that silver nanoparticles are lethal to zebrafish. PMID:22174711

  10. Polymethoxy-1-alkenes from Aphanizomenon ovalisporum Inhibit Vertebrate Development in the Zebrafish (Danio rerio Embryo Model

    Directory of Open Access Journals (Sweden)

    John P. Berry

    2012-10-01

    Full Text Available Cyanobacteria are recognized producers of a wide array of toxic or otherwise bioactive secondary metabolites. The present study utilized the zebrafish (Danio rerio embryo as an aquatic animal model of vertebrate development to identify, purify and characterize lipophilic inhibitors of development (i.e., developmental toxins from an isolate of the freshwater cyanobacterial species, Aphanizomenon ovalisporum. Bioassay-guided fractionation led to the purification, and subsequent chemical characterization, of an apparent homologous series of isotactic polymethoxy-1-alkenes (1–6, including three congeners (4–6 previously identified from the strain, and two variants previously identified from other species (2 and 3, as well as one apparently novel member of the series (1. Five of the PMAs in the series (1–5 were purified in sufficient quantity for comparative toxicological characterization, and toxicity in the zebrafish embryo model was found to generally correlate with relative chain length and/or methoxylation. Moreover, exposure of embryos to a combination of variants indicates an apparent synergistic interaction between the congeners. Although PMAs have been identified previously in cyanobacteria, this is the first report of their apparent toxicity. These results, along with the previously reported presence of the PMAs from several cyanobacterial species, suggest a possibly widespread distribution of the PMAs as toxic secondary metabolites and warrants further chemical and toxicological investigation.

  11. A Fluorescence-Based Assay for Proteinuria Screening in Larval Zebrafish (Danio rerio).

    Science.gov (United States)

    Hanke, Nils; King, Benjamin L; Vaske, Bernhard; Haller, Hermann; Schiffer, Mario

    2015-10-01

    Analysis of genes compromising the glomerular filtration barrier in rodent models using transgenic or knockdown approaches is time- and resource-consuming and often leads to unsatisfactory results. Therefore, it would be beneficial to have a selection tool indicating that your gene of interest is in fact associated with proteinuria. Zebrafish (Danio rerio) is a rapid screening tool to study effects in glomerular filtration barrier integrity after genetic manipulation. We use either injection of high-molecular-weight dextrans or a transgenic fluorescent fish line [Tg(l-fabp:DBP:EGFP)] expressing a vitamin D-binding protein fused with eGFP for indirect detection of proteinuria. A loss of high-molecular-weight proteins from the circulation of the fish into the urine can be identified by monitoring fluorescence intensity in the zebrafish eye. Paired with an optimized analysis method, this assay provides an effective screening solution to detect filtration barrier damage with proteinuria before moving to a mammalian system. PMID:26125680

  12. The Effects of Salicylic Acid on Juvenile Zebrafish Danio rerio Under Flow-Through Conditions.

    Science.gov (United States)

    Zivna, Dana; Blahova, Jana; Siroka, Zuzana; Plhalova, Lucie; Marsalek, Petr; Doubkova, Veronika; Zelinska, Gabriela; Vecerek, Vladimir; Tichy, Frantisek; Sehonova, Pavla; Svobodova, Zdenka

    2016-09-01

    The aquatic environment is becoming increasingly contaminated with pharmaceuticals. Salicylic acid (SA), which can be used individually or appear as a degradation product of the widely used acetylsalicylic acid was chosen for testing. Juvenile zebrafish Danio rerio were subjected to OECD test No. 215 (fish, juvenile growth test) with salicylic acid concentrations of 0.004; 0.04; 0.4; 4 and 40 mg/L. Specific growth rate (SGR), histological changes, and parameters of oxidative stress were evaluated. SA had no effects on histological changes, SGR, glutathione reductase, and lipid peroxidation. Increased catalytic activity of GPx was found at 0.04 mg/L compared to control, increased catalytic activity of catalase was found at 0.04 and 4 mg/L compared to control, and increased catalytic activity of glutathione-S-transferase was found at 0.004 and 0.04 mg/L compared to control (P < 0.05). Juvenile zebrafish turned out to be relatively insensitive to both environmentally relevant (0.004 mg/L) and higher concentrations of salicylic acid. PMID:27385367

  13. Toxicity assessment of iron oxide nanoparticles in zebrafish (Danio rerio early life stages.

    Directory of Open Access Journals (Sweden)

    Xiaoshan Zhu

    Full Text Available Iron oxide nanoparticles have been explored recently for their beneficial applications in many biomedical areas, in environmental remediation, and in various industrial applications. However, potential risks have also been identified with the release of nanoparticles into the environment. To study the ecological effects of iron oxide nanoparticles on aquatic organisms, we used early life stages of the zebrafish (Danio rerio to examine such effects on embryonic development in this species. The results showed that ≥10 mg/L of iron oxide nanoparticles instigated developmental toxicity in these embryos, causing mortality, hatching delay, and malformation. Moreover, an early life stage test using zebrafish embryos/larvae is also discussed and recommended in this study as an effective protocol for assessing the potential toxicity of nanoparticles. This study is one of the first on developmental toxicity in fish caused by iron oxide nanoparticles in aquatic environments. The results will contribute to the current understanding of the potential ecotoxicological effects of nanoparticles and support the sustainable development of nanotechnology.

  14. In Vivo Toxicity of Silver Nanoparticles and Silver Ions in Zebrafish (Danio rerio

    Directory of Open Access Journals (Sweden)

    Katrine Bilberg

    2012-01-01

    Full Text Available The influence of water chemistry on characterised polyvinyl pyrrolidone- (PVP- coated silver nanoparticles (81 nm was investigated. NaCl solution series of 100–800 mg L−1 lead to initial and temporal increase in nanoparticles size, but agglomeration was limited. pH variation (5–8 had only minor influence on the hydrodynamic particle size. Acute toxicity of nanosivler to zebrafish (Danio rerio was investigated in a 48-hour static renewal study and compared with the toxicity of silver ions (AgNO3. The nanosilver and silver ion 48-hour median lethal concentration (LC50 values were 84 μg L−1 and 25 μg L−1, respectively. To investigate exposure-related stress, the fish behaviour was observed visually after 0, 3, 6, 12, 24, 27, 30, and 48 hours of both nanosilver and ionic silver treatments. These observations revealed increased rate of operculum movement and surface respiration after nanosilver exposure, suggesting respiratory toxicity. The present study demonstrates that silver nanoparticles are lethal to zebrafish.

  15. In Vivo Determination of Body Composition in Zebrafish (Danio rerio) by Quantitative Magnetic Resonance.

    Science.gov (United States)

    Fowler, L Adele; Dennis, Lacey N; Barry, R Jeff; Powell, Mickie L; Watts, Stephen A; Smith, Daniel L

    2016-06-01

    Zebrafish (Danio rerio) as a model research organism continues to expand its relevance and role in multiple research disciplines, with recent work directed toward models of metabolism, nutrition, and energetics. Multiple technologies exist to assess body composition in animal research models at various levels of detail (tissues/organs, body regions, and whole organism). The development and/or validation of body composition assessment tools can open new areas of research questions for a given organism. Using fish from a comparative nutrition study, quantitative magnetic resonance (QMR) assessment of whole body fat and fat-free mass (FFM) in live fish was performed. QMR measures from two cohorts (n = 26 and n = 27) were compared with chemical carcass analysis (CCA) of FM and FFM. QMR was significantly correlated with chemical carcass values (fat, p FFM (-0.024 g; p FFM (p = 0.753). These results support the utilization of QMR-a nonlethal nondestructive method-for cross-sectional or longitudinal body composition assessment outcomes in zebrafish. PMID:26974510

  16. The Effects of Salicylic Acid on Juvenile Zebrafish Danio rerio Under Flow-Through Conditions.

    Science.gov (United States)

    Zivna, Dana; Blahova, Jana; Siroka, Zuzana; Plhalova, Lucie; Marsalek, Petr; Doubkova, Veronika; Zelinska, Gabriela; Vecerek, Vladimir; Tichy, Frantisek; Sehonova, Pavla; Svobodova, Zdenka

    2016-09-01

    The aquatic environment is becoming increasingly contaminated with pharmaceuticals. Salicylic acid (SA), which can be used individually or appear as a degradation product of the widely used acetylsalicylic acid was chosen for testing. Juvenile zebrafish Danio rerio were subjected to OECD test No. 215 (fish, juvenile growth test) with salicylic acid concentrations of 0.004; 0.04; 0.4; 4 and 40 mg/L. Specific growth rate (SGR), histological changes, and parameters of oxidative stress were evaluated. SA had no effects on histological changes, SGR, glutathione reductase, and lipid peroxidation. Increased catalytic activity of GPx was found at 0.04 mg/L compared to control, increased catalytic activity of catalase was found at 0.04 and 4 mg/L compared to control, and increased catalytic activity of glutathione-S-transferase was found at 0.004 and 0.04 mg/L compared to control (P < 0.05). Juvenile zebrafish turned out to be relatively insensitive to both environmentally relevant (0.004 mg/L) and higher concentrations of salicylic acid.

  17. Polymerase Chain Reaction Detection of Pseudoloma neurophilia, a Common Microsporidian of Zebrafish (Danio rerio) Reared in Research Laboratories

    OpenAIRE

    Whipps, Christopher M.; Kent, Michael L

    2006-01-01

    One of the most prevalent pathogens found in zebrafish (Danio rerio) research facilities is the microsporidian parasite Pseudoloma neurophilia. Infections occur primarily in the spinal cord and are associated with emaciation and scoliotic changes. It is unclear why P. neurophilia is so widespread among research colonies, although transfer of infected animals and eggs between laboratories is a likely contributor. In addition to preventing the spread of this pathogen among facilities, it is des...

  18. Teratogenicity of Ochratoxin A and the Degradation Product, Ochratoxin α, in the Zebrafish (Danio rerio) Embryo Model of Vertebrate Development

    OpenAIRE

    Mehreen Haq; Nelson Gonzalez; Keenan Mintz; Asha Jaja-Chimedza; Christopher Lawrence De Jesus; Christina Lydon; Welch, Aaron Z.; Berry, John P.

    2016-01-01

    Ochratoxins, and particularly ochratoxin A (OTA), are toxic fungal-derived contaminants of food and other agricultural products. Growing evidence supports the degradation of OTA by chemical, enzymatic and/or microbial means as a potential approach to remove this mycotoxin from food products. In particular, hydrolysis of OTA to ochratoxin α (OTα) and phenylalanine is the presumptive product of degradation in most cases. In the current study, we employed the zebrafish (Danio rerio) embryo, as a...

  19. Chronic exposure to low benzo[a]pyrene level causes neurodegenerative disease-like syndromes in zebrafish (Danio rerio).

    Science.gov (United States)

    Gao, Dongxu; Wu, Meifang; Wang, Chonggang; Wang, Yuanchuan; Zuo, Zhenghong

    2015-10-01

    Previous epidemiological and animal studies report that exposure to environmental pollutant exposure links to neurodegenerative diseases such as Parkinson's disease and Alzheimer's disease. Benzo[a]pyrene (BaP), a neurotoxic polycyclic aromatic hydrocarbon, has been increasingly released into the environment during recent decades. So far, the role of BaP on the development of neurodegenerative diseases remaind unclear. This study aimed to determine whether chronic exposure to low dose BaP would cause neurodegenerative disease-like syndromes in zebrafish (Danio rerio). We exposed zebrafish, from early embryogenesis to adults, to environmentally relevant concentrations of BaP for 230 days. Our results indicated that BaP decreased the brain weight to body weight ratio, locomotor activity and cognitive ability; induced the loss of dopaminergic neurons; and resulted in neurodegeneration. In addition, obvious cell apoptosis in the brain was found. Furthermore, the neurotransmitter levels of dopamine and 3,4-dihydroxyphenylacetic acid, the mRNA levels of the genes encoding dopamine transporter, Parkinson protein 7, phosphatase and tensin-induced putative kinase 1, ubiquitin carboxy-terminal hydrolase L1, leucine-rich repeat serine/threonine kinase 2, amyloid precursor protein b, presenilin 1 and presenilin 2 were significantly down-regulated by BaP exposure. These findings suggest that chronic exposure to low dose BaP could cause the behavioral, neuropathological, neurochemical, and genetic features of neurodegenerative diseases. This study provides clues that BaP may constitute an important environmental risk factor for neurodegenerative diseases in humans. PMID:26349946

  20. Chronic effects of clofibric acid in zebrafish (Danio rerio): A multigenerational study

    Energy Technology Data Exchange (ETDEWEB)

    Coimbra, Ana M., E-mail: acoimbra@utad.pt [Centre for The Research and Technology of Agro-Environmental and Biological Sciences (CITAB), University of Trás-os-Montes e Alto Douro (UTAD), Quinta de Prados, 5000-801 Vila Real (Portugal); Department of Biology and Environment, Life Sciences and Environment School (ECVA), University of Trás-os-Montes e Alto Douro (UTAD), Quinta de Prados, 5000-801 Vila Real (Portugal); Peixoto, Maria João [CIMAR/CIIMAR, Interdisciplinary Centre for Marine and Environmental Research, University of Porto, Rua dos Bragas 177, 4050-123 Porto (Portugal); Department of Biology and Environment, Life Sciences and Environment School (ECVA), University of Trás-os-Montes e Alto Douro (UTAD), Quinta de Prados, 5000-801 Vila Real (Portugal); Coelho, Inês; Lacerda, Ricardo [CIMAR/CIIMAR, Interdisciplinary Centre for Marine and Environmental Research, University of Porto, Rua dos Bragas 177, 4050-123 Porto (Portugal); Carvalho, António Paulo [CIMAR/CIIMAR, Interdisciplinary Centre for Marine and Environmental Research, University of Porto, Rua dos Bragas 177, 4050-123 Porto (Portugal); FCUP, Faculty of Sciences University of Porto, Department of Biology, Rua do Campo Alegre, 4169-007 Porto (Portugal); Gesto, Manuel [CIMAR/CIIMAR, Interdisciplinary Centre for Marine and Environmental Research, University of Porto, Rua dos Bragas 177, 4050-123 Porto (Portugal); Department of Functional Biology and Health Sciences, Faculty of Biology, University of Vigo, As Lagoas-Marcosende s/n, 36310, Vigo (Spain); Lyssimachou, Angeliki; Lima, Daniela; Soares, Joana; André, Ana; Capitão, Ana [CIMAR/CIIMAR, Interdisciplinary Centre for Marine and Environmental Research, University of Porto, Rua dos Bragas 177, 4050-123 Porto (Portugal); and others

    2015-03-15

    Highlights: • Clofibric acid (CA) induces multigenerational effects in zebrafish (Danio rerio). • CA impacts fish lipid metabolism, with similarities to those reported in mammals. • Weight is impacted in F1 and F2 generations, thought with opposite patterns. - Abstract: Clofibric acid (CA) is an active metabolite of the blood lipid lowering agent clofibrate, a pharmaceutical designed to work as agonist of peroxisome proliferator-activated receptor alpha (PPARa). It is the most commonly reported fibrate in aquatic environments with low degradation rate and potential environmental persistence. Previous fish exposures showed that CA may impact spermatogenesis, growth and the expression of fat binding protein genes. However, there are limited data on the effects of chronic multigenerational CA exposures. Here, we assessed chronic multigenerational effects of CA exposure using zebrafish (Danio rerio) as a teleost model. Zebrafish were exposed through the diet to CA (1 and 10 mg/g) during their whole lifetime. Growth, reproduction-related parameters and embryonic development were assessed in the exposed fish (F1 generation) and their offspring (F2 generation), together with muscle triglyceride content and gonad histology. In order to study the potential underlying mechanisms, the transcription levels of genes coding for enzymes involved in lipid metabolism pathways were determined. The results show that chronic life-cycle exposure to CA induced a significant reduction in growth of F1 generation and lowered triglyceride muscle content (10 mg/g group). Also, an impact in male gonad development was observed together with a decrease in the fecundity (10 mg/g group) and higher frequency of embryo abnormalities in the offspring of fish exposed to the lowest CA dose. The profile of the target genes was sex- and tissue-dependent. In F1 an up-regulation of male hepatic pparaa, pparb and acox transcript levels was observed, suggesting an activation of the fatty acid

  1. Chronic effects of clofibric acid in zebrafish (Danio rerio): A multigenerational study

    International Nuclear Information System (INIS)

    Highlights: • Clofibric acid (CA) induces multigenerational effects in zebrafish (Danio rerio). • CA impacts fish lipid metabolism, with similarities to those reported in mammals. • Weight is impacted in F1 and F2 generations, thought with opposite patterns. - Abstract: Clofibric acid (CA) is an active metabolite of the blood lipid lowering agent clofibrate, a pharmaceutical designed to work as agonist of peroxisome proliferator-activated receptor alpha (PPARa). It is the most commonly reported fibrate in aquatic environments with low degradation rate and potential environmental persistence. Previous fish exposures showed that CA may impact spermatogenesis, growth and the expression of fat binding protein genes. However, there are limited data on the effects of chronic multigenerational CA exposures. Here, we assessed chronic multigenerational effects of CA exposure using zebrafish (Danio rerio) as a teleost model. Zebrafish were exposed through the diet to CA (1 and 10 mg/g) during their whole lifetime. Growth, reproduction-related parameters and embryonic development were assessed in the exposed fish (F1 generation) and their offspring (F2 generation), together with muscle triglyceride content and gonad histology. In order to study the potential underlying mechanisms, the transcription levels of genes coding for enzymes involved in lipid metabolism pathways were determined. The results show that chronic life-cycle exposure to CA induced a significant reduction in growth of F1 generation and lowered triglyceride muscle content (10 mg/g group). Also, an impact in male gonad development was observed together with a decrease in the fecundity (10 mg/g group) and higher frequency of embryo abnormalities in the offspring of fish exposed to the lowest CA dose. The profile of the target genes was sex- and tissue-dependent. In F1 an up-regulation of male hepatic pparaa, pparb and acox transcript levels was observed, suggesting an activation of the fatty acid

  2. Correlating gene expression with deformities caused by aryl hydrocarbon receptor agonists in zebrafish (Danio rerio)

    Energy Technology Data Exchange (ETDEWEB)

    Bugiak, B.; Weber, L. [Saskatchewan Univ., Saskatoon, SK (Canada)

    2009-07-01

    Exposure to aryl hydrocarbon receptor (AhR) agonists in fish causes lethal disturbances in fish development, but the effects of acute AhR agonist exposure on the cardiovascular system and deformities remain unclear. This study addressed this issue by performing a series of experiments on zebrafish (Danio rerio). The authors hypothesized that genes needed for cardiovascular regulation (PTGS) would exhibit a stronger link to deformities than detoxification enzymes (CYPs). Zebrafish eggs were exposed aqueously until 4 days post-fertilization (dpf) to the AhR agonists benzo(a)pyrene (BaP) or 2,3,7,8-tetrachlorodibenzop-dioxin (TCDD) alone and in combination with the putative AhR antagonists resveratrol or alpha-naphthoflavone (ANF). Gene expression was measured using real-time, reverse transcriptase PCR in zebrafish at 5 and 10 dpf. Although the mortalities did not differ considerably among groups at 10 dpf, the deformities increased significantly after BaP-ANF at 5 dpf and after BaP at 10 dpf, but not after TCDD treatment. CYP and PTGS isozymes exhibited small, but statistically significant changes at 5 dpf. By 10 dpf, the expression returned to control values. In general, CYP1A and PTGS-1 expression at 5 dpf were positively correlated with deformities, while all other genes were negatively correlated with deformities. It was concluded that changes in CYP1A, CYP1C2, and PTGS-1 gene expression at 5 dpf are associated with developmental deformities, but additional work is needed to determine which has the most important mechanistic link.

  3. Toxic effects of perfluorononanoic acid on the development of Zebrafish (Danio rerio) embryos.

    Science.gov (United States)

    Liu, Hui; Sheng, Nan; Zhang, Wei; Dai, Jiayin

    2015-06-01

    Perfluorononanoic acid (PFNA) is a nine-carbon perfluoroalkyl acid widely used in industrial and domestic products. It is a persistent organic pollutant found in the environment as well as in the tissues of humans and wildlife. There is a concern that this chemical might be a developmental toxicant and teratogen in various ecosystems. In the present study, the toxic effects of PFNA were evaluated in zebrafish (Danio rerio) embryos. One hour post-fertilization embryos were treated with 0, 25, 50, 100, 200, 300, 350, and 400 μmol/L PFNA for 96 hr in 6-well plates. Developmental phenotypes and hatching rates were observed and recorded. Nineteen genes related to oxidative stress and lipid metabolism were examined using Quantitative RT-PCR and confirmed by whole mount in situ hybridization (WISH). Results showed that PFNA delayed the development of zebrafish embryos, reduced the hatching rate, and caused ventricular edema and malformation of the spine. In addition, the amount of reactive oxygen species in the embryo bodies increased significantly after exposure to PFNA compared with that of the control group. The Quantitative RT-PCR and WISH experiments demonstrated that mRNA expression of the lfabp and ucp2 genes increased significantly while that of sod1 and mt-nd1 decreased significantly after PFNA exposure. The mRNA expression levels of gpx1 and mt-atp6 decreased significantly in the high concentration group. However, the mRNA expression levels of both ppara and pparg did not show any significant variation after exposure. These findings suggest that PFNA affected the development of zebrafish embryos at relatively low concentrations. PMID:26040728

  4. Combined effects of alpha particles and depleted uranium on Zebrafish (Danio rerio) embryos

    Science.gov (United States)

    Ng, Candy Y.P.; Pereira, Sandrine; Cheng, Shuk Han; Adam-Guillermin, Christelle; Garnier-Laplace, Jacqueline; Yu, Kwan Ngok

    2016-01-01

    The combined effects of low-dose or high-dose alpha particles and depleted uranium (DU) in Zebrafish (Danio rerio) embryos were studied. Three schemes were examined—(i) [ILUL]: 0.44 mGy alpha-particle dose + 10 µg/l DU exposure, (ii) [IHUH]: 4.4 mGy alpha-particle dose + 100 µg/l DU exposure and (iii) [IHUL]: 4.4 mGy alpha-particle dose + 10 µg/l DU exposure—in which Zebrafish embryos were irradiated with alpha particles at 5 h post fertilization (hpf) and/or exposed to uranium at 5–6 hpf. The results were also compared with our previous work, which studied the effects of [ILUH]: 0.44 mGy alpha-particle dose + 100 µg/l DU exposure. When the Zebrafish embryos developed to 24 hpf, the apoptotic signals in the entire embryos, used as the biological endpoint for this study, were quantified. Our results showed that [ILUL] and [IHUL] led to antagonistic effects, whereas [IHUH] led to an additive effect. The effect found for the previously studied case of [ILUH] was difficult to define because it was synergistic with reference to the 100 µg/l DU exposure, but it was antagonistic with reference to the 0.44 mGy alpha-particle dose. All the findings regarding the four different schemes showed that the combined effects critically depended on the dose response to each individual stressor. We also qualitatively explained these findings in terms of promotion of early death of cells predisposed to spontaneous transformation by alpha particles, interacting with the delay in cell death resulting from various concentrations of DU exposure. PMID:26937024

  5. Studies on membrane permeability of zebrafish (Danio rerio) oocytes in the presence of different cryoprotectants.

    Science.gov (United States)

    Zhang, Tiantian; Isayeva, Anna; Adams, Serean L; Rawson, David M

    2005-06-01

    Investigation into fish oocyte membrane permeability is essential for developing successful protocols for their cryopreservation. The aim of the present work was to study the permeability of the zebrafish (Danio rerio) oocyte membrane to water and cryoprotectants before cryopreservation protocol design. The study was conducted on stage III and stage V zebrafish oocytes. Volumetric changes of stage III oocytes in different concentrations of sucrose were measured after 20 min exposure at 22 degrees C and the osmotically inactive volume of the oocytes (Vb) was determined using the Boyle-van't Hoff relationship. Volumetric changes of oocytes during exposure to different cryoprotectant solutions were also measured. Oocytes were exposed to 2 M dimethyl sulphoxide (DMSO), propylene glycol (PG), and methanol for 40 min at 22 degrees C. Stage III oocytes were also exposed to 2 M DMSO at 0 degrees C. Oocyte images were captured on an Olympus BX51 cryomicroscope using Linkham software for image recording. Scion Image was used for image analysis and diameter measurement. The experimental data were fitted to a two-parameter model using Berkeley Madonna 8.0.1 software. Hydraulic conductivity (L(p)) and solute (cryoprotectant) permeability (Ps) were estimated using the model. The osmotically inactive volume of stage III zebrafish oocytes was found to be 69.5%. The mean values+/-SE of Lp were found to be 0.169+/-0.02 and 0.196+/-0.01 microm/min/atm in the presence of DMSO and PG, respectively, at 22 degrees C, assuming an internal isosmotic value for the oocyte of 272 mOsm. The Ps values were 0.000948+/-0.00015 and 0.000933+/-0.00005 cm/min for DMSO and PG, respectively. It was also shown that the membrane permeability of stage III oocytes decreased significantly with temperature. No significant changes in cell volume during methanol treatment were observed. Fish oocyte membrane permeability parameters are reported here for the first time. The Lp and Ps values obtained for stage

  6. Enantioselective developmental toxicity and immunotoxicity of pyraclofos toward zebrafish (Danio rerio)

    Energy Technology Data Exchange (ETDEWEB)

    Zhuang, Shulin, E-mail: shulin@zju.edu.cn [Institute of Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058 (China); Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou 310058 (China); Zhang, Zhisheng [Institute of Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058 (China); Zhang, Wenjing; Bao, Lingling [Institute of Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058 (China); Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou 310058 (China); Xu, Chao, E-mail: chaoxu@zjut.edu.cn [Research Center of Environmental Science, College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032 (China); Zhang, Hu [Institute of Quality and Standard for Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou 210021 (China)

    2015-02-15

    Highlights: • Pyraclofos has significant enantioselective aquatic toxicities to zebrafish. • Pyraclofos induces time- and concentration-dependent developmental toxicity and immunotoxicity. • The mRNA level of IL-1β gene was significantly up-regulated by pyraclofos. • Pyraclofos binds potently to IL-1β, potentially affecting IL-1β-dependent proinflammatory signal transduction. • Our in vitro and in silico studies help to understand the molecular basis for aquatic toxicity of pyraclofos. - Abstract: Pyraclofos, a relatively new organophosphorus pesticide, has shown potential ecotoxicities, however, its aquatic toxicity, especially enantioselective aquatic toxicity, remains largely unknown. Using zebrafish (Danio rerio) as a preeminent vertebrate aquatic model, the enantioselective differences in the developmental toxicity and immunotoxicity of pyraclofos were evaluated. Following 96-h exposure, pyraclofos enantiomers exhibited acute toxicity and showed lethal concentration 50 of 2.23 and 3.99 mg/L for (R)-Pyraclofos and (S)-Pyraclofos, respectively. Exposure to pyraclofos caused time- and concentration-dependent malformations such as pericardial edema, yolk sac edema, crooked bodies and hatching during the embryonic development, with markedly higher percentages of malformation at higher concentrations. The concentration-dependent immunotoxicity to zebrafish embryo exposed to low level pyraclofos was induced with significant up-regulation of mRNA levels of immune-related interleukin-1β (IL-1β) gene. (R)-Pyraclofos was consistently more toxic than (S)-Pyraclofos for the acute toxicity, developmental toxicity and immunotoxicity to zebrafish. Molecular dynamics simulations revealed that at the atomic level, (R)-Pyraclofos binds more potently to IL-1β protein than (S)-Pyraclofos. This enantioselective binding is mainly contributed by the distinct binding mode of pyraclofos enantiomers and their electrostatic interactions with IL-1β, which potentially

  7. Persistence of endocrine disruption in zebrafish (Danio rerio) after discontinued exposure to the androgen 17β-trenbolone

    DEFF Research Database (Denmark)

    Baumann, Lisa; Knörr, Susanne; Keiter, Susanne;

    2014-01-01

    The aim of the present study was to investigate the effects of the androgenic endocrine disruptor 17β-trenbolone on the sexual development of zebrafish (Danio rerio) with special emphasis on the question whether adverse outcomes of developmental exposure are reversible or persistent. An exposure...... with respect to exposure duration nor to concentration. Gonad morphological masculinization as well as the decrease of vitellogenin persisted after depuration over 40 d in clean water. This lack of recovery suggests that androgenic effects on sexual development of zebrafish are irreversible....... scenario including a recovery phase was chosen to assess the potential reversibility of androgenic effects. Zebrafish were exposed to environmentally relevant concentrations of 17β-trenbolone (1 - 30 ng/L) from fertilization until completion of gonad sexual differentiation (60 days post-hatch, dph...

  8. Reversibility of endocrine disruption in zebrafish (Danio rerio) after discontinued exposure to the estrogen 17α-ethinylestradiol

    DEFF Research Database (Denmark)

    Baumann, Lisa; Knörr, Susanne; Keiter, Susanne;

    2014-01-01

    to examine the estrogenic effects on sexual development of zebrafish. Two exposure scenarioswere compared: continuous exposure to environmentally relevant concentrations (0.1–10 ng/L EE2) up to 100 days post-hatch (dph) and developmental exposure up to 60 dph, followed by 40 days of depuration in clean water....... The persistence of effects was investigated at different biological organization levels from mRNA to population-relevant endpoints to cover a broad range of important parameters. EE2 had a strong feminizing and inhibiting effect on the sexual development of zebrafish. Brain aromatase (cyp19b)mRNA expression......The aim of the present study was to investigate the persistence of the feminizing effects of discontinued 17α-ethinylestradiol (EE2) exposure on zebrafish (Danio rerio). An exposure scenario covering the sensitive phase of sexual differentiation, as well as final gonad maturation was chosen...

  9. In silico and in situ characterization of the zebrafish (Danio rerio gnrh3 (sGnRH gene

    Directory of Open Access Journals (Sweden)

    Husebye Harald

    2002-08-01

    Full Text Available Abstract Background Gonadotropin releasing hormone (GnRH is responsible for stimulation of gonadotropic hormone (GtH in the hypothalamus-pituitary-gonadal axis (HPG. The regulatory mechanisms responsible for brain specificity make the promoter attractive for in silico analysis and reporter gene studies in zebrafish (Danio rerio. Results We have characterized a zebrafish [Trp7, Leu8] or salmon (s GnRH variant, gnrh3. The gene includes a 1.6 Kb upstream regulatory region and displays the conserved structure of 4 exons and 3 introns, as seen in other species. An in silico defined enhancer at -976 in the zebrafish promoter, containing adjacent binding sites for Oct-1, CREB and Sp1, was predicted in 2 mammalian and 5 teleost GnRH promoters. Reporter gene studies confirmed the importance of this enhancer for cell specific expression in zebrafish. Interestingly the promoter of human GnRH-I, known as mammalian GnRH (mGnRH, was shown capable of driving cell specific reporter gene expression in transgenic zebrafish. Conclusions The characterized zebrafish Gnrh3 decapeptide exhibits complete homology to the Atlantic salmon (Salmo salar GnRH-III variant. In silico analysis of mammalian and teleost GnRH promoters revealed a conserved enhancer possessing binding sites for Oct-1, CREB and Sp1. Transgenic and transient reporter gene expression in zebrafish larvae, confirmed the importance of the in silico defined zebrafish enhancer at -976. The capability of the human GnRH-I promoter of directing cell specific reporter gene expression in zebrafish supports orthology between GnRH-I and GnRH-III.

  10. Microcystin-LR induced developmental toxicity and apoptosis in zebrafish (Danio rerio) larvae by activation of ER stress response.

    Science.gov (United States)

    Qi, Mei; Dang, Yao; Xu, Qinglong; Yu, Liqin; Liu, Chunsheng; Yuan, Yongchao; Wang, Jianghua

    2016-08-01

    Recent studies have demonstrated that cyanobacteria-derived Microcystin-LR (MC-LR) can cause developmental toxicity and trigger apoptosis in zebrafish (Danio rerio) larvae, but the underlying mechanisms remain largely unknown. In this study, we tested the hypothesis that the mechanism by which MC-LR induces developmental toxicity is through activation of endoplasmic reticulum (ER) stress. MC-LR (4.0 μM) exposure through submersion caused serious developmental toxicity, such as malformation, growth delay and decreased heart rates in zebrafish larvae, which could be inhibited by ER stress blocker, tauroursodeoxycholic acid (TUDCA, 20 μM). Meanwhile, acridine orange (AO) staining showed TUDCA could rescue cell apoptosis in heart area in zebrafish larvae resulted by MC-LR exposure. Real-time polymerase chain reaction (real-time PCR) analysis demonstrated that MC-LR induced activation of ER stress which consequently triggered apoptosis in zebrafish larvae. Protein expression examined by western blot indicated that MC-LR could activate MAPK8/Bcl-2/Bax pathway and caspase-dependent apoptotic pathway in zebrafish larva and the effects were mitigated by inhibition of ER stress. Taken together, the results observed in this study suggested that ER stress plays a critical role in developmental toxicity and apoptosis in zebrafish embryos exposed to MC-LR. PMID:27219292

  11. Verification of intraovum transmission of a microsporidium of vertebrates: Pseudoloma neurophilia infecting the Zebrafish, Danio rerio.

    Directory of Open Access Journals (Sweden)

    Justin L Sanders

    Full Text Available Direct transmission from parents to offspring, referred to as vertical transmission, occurs within essentially all major groups of pathogens. Several microsporidia (Phylum Microsporidia that infect arthropods employ this mode of transmission, and various lines of evidence have suggested this might occur with certain fish microsporidia. The microsporidium, Pseudoloma neurophilia, is a common pathogen of the laboratory zebrafish, Danio rerio. We previously verified that this parasite is easily transmitted horizontally, but previous studies also indicated that maternal transmission occurs. We report here direct observation of Pseudoloma neurophilia in the progeny of infected zebrafish that were reared in isolation, including microscopic visualization of the parasite in all major stages of development. Histological examination of larval fish reared in isolation from a group spawn showed microsporidian spores in the resorbing yolk sac of a fish. Infections were also observed in three of 36 juvenile fish. Eggs from a second group spawn of 30 infected fish were examined using a stereomicroscope and the infection was observed from 4 to 48 hours post-fertilization in two embryos. Intraovum infections were detected in embryos from 4 of 27 pairs of infected fish that were spawned based on qPCR detection of P. neurophilia DNA. The prevalence of intraovum infections from the four spawns containing infected embryos was low (∼1% based on calculation of prevalence using a maximum likelihood analysis for pooled samples. Parasite DNA was detected in the water following spawning of 11 of the infected pairs, suggesting there was also potential for extraovum transmission in these spawning events. Our study represents the first direct observation of vertical transmission within a developing embryo of a microsporidian parasite in a vertebrate. The low prevalence of vertical transmission in embryos is consistent with observations of some other fish pathogens that are

  12. PACAP in developing sensory and peripheral organs of the zebrafish, Danio rerio

    Directory of Open Access Journals (Sweden)

    M Mathieu

    2009-06-01

    Full Text Available The anatomical distribution of PACAP-like immunoreactivity was investigated in sensory and peripheral organs of the zebrafish, Danio rerio, during the pharyngula, hatching and larval periods, by using indirect immunofluorescence methods. First PACAP-like immunoreactive (ir elements appeared during the pharyngula period, at 24 hours post fertilization (hpf, within the most superficial layer of the retina and the dorsal aorta. At 48 hpf, additional ir cells were found in the olfactory placode and esophagus. At 72 hpf (hatching period, PACAP-like immunoreactivity was first detected in the ganglion cell layer of the retina, the otic sensory epithelium, pharyngeal arches, swim bladder and pancreatic progenitor cells. During day 5 of larval development, new groups of ir cells appeared in the liver, whereas no ir elements were observed in the olfactory placode. Subsequently, at day 13 of larval development, additional ir elements were found for the first time in some gut epithelial cells while those previously observed in the retina and otic sensory epithelium were absent. The transient expression of PACAP-like ir material in sensory organs suggests that the peptide could be implicated in neurotrophic activities and neurosensorial connections in the migration and/or differentiation processes. The appearance of PACAP-like ir elements in peripheral organs at different developmental stages, indicates that this peptide could be involved in the control of more specific functions as soon as these peripheral structures begin to operate.

  13. Combined effects of silver nanoparticles and mercury on gill histopathology of zebrafish (Danio rerio

    Directory of Open Access Journals (Sweden)

    Borhan Mansouri

    2016-06-01

    Full Text Available Objective: To evaluate the combined effects of silver nanoparticles (Ag NPs and Hg2+ on the gill histopathology of zebrafish (Danio rerio under the controlled conditions. Methods: In this study, one non-lethal concentration of Ag NPs (0.1 mg/L, six concentrations of Hg2+ (0.001, 0.005, 0.01, 0.05, 0.1 and 0.2 mg/L, and six mixture concentrations of Ag NPs and Hg2+ (0.1 plus 0.001, 0.005, 0.01, 0.05, 0.1, and 0.2 mg/L were used as the control group. After 4 days of exposure, samples were prepared for gill histology. Results: The results showed that notable damages were observed in aneurism, such as vacuolation of secondary lamella, fusion, hypertrophy, mucus secretion and necrosis. Moreover, our findings indicated that the Hg2+ and Ag NPs alone led to shorter secondary lamella length and smaller lamellae’s diameter of gills compared to the mixture of Ag NPs and Hg2+. However, the extent of damages in gill tissues after exposure to mixture of Ag NPs and Hg2+ was lower than Hg2+ ions and Ag NPs. Conclusions: It appears that the presence of Ag NPs can potentially reduce the toxicity of Hg2+ ions. However, to assess the toxicity mechanisms of nanoparticles in presence of pollutants, further studies should be encouraged.

  14. Combined effects of silver nanoparticles and mercury on gill histopathology of zebrafish (Danio rerio)

    Institute of Scientific and Technical Information of China (English)

    Borhan Mansouri; Raouf Rahmani; NammamAliAzadi; SeyedAli Johari

    2016-01-01

    Objective: To evaluate the combined effects of silver nanoparticles (Ag NPs) and Hg2+ on the gill histopathology of zebrafish (Danio rerio) under the controlled conditions. Methods: In this study, one non-lethal concentration of Ag NPs (0.1 mg/L), six concentrations of Hg2+ (0.001, 0.005, 0.01, 0.05, 0.1 and 0.2 mg/L), and six mixture concentrations of Ag NPs and Hg2+ (0.1 plus 0.001, 0.005, 0.01, 0.05, 0.1, and 0.2 mg/L) were used as the control group. After 4 days of exposure, samples were prepared for gill histology. Results: The results showed that notable damages were observed in aneurism, such as vacuolation of secondary lamella, fusion, hypertrophy, mucus secretion and necrosis. Moreover, our findings indicated that the Hg2+ and Ag NPs alone led to shorter secondary lamella length and smaller lamellae’s diameter of gills compared to the mixture of Ag NPs and Hg2+. However, the extent of damages in gill tissues after exposure to mixture of Ag NPs and Hg2+ was lower than Hg2+ ions and Ag NPs. Conclusions: It appears that the presence of Ag NPs can potentially reduce the toxicity of Hg2+ions. However, to assess the toxicity mechanisms of nanoparticles in presence of pollutants, further studies should be encouraged.

  15. Ultraviolet B radiation alters movement and thermal selection of zebrafish (Danio rerio).

    Science.gov (United States)

    Seebacher, Frank; Kazerouni, Ensiyeh Ghanizadeh; Franklin, Craig E

    2016-08-01

    Temperature and ultraviolet B (UV-B) interact in causing cellular damage and impairing locomotor performance. Here, we test the hypothesis that movement and thermal selection of zebrafish (Danio rerio) change in the presence of UV-B, and in particular, that fish which were chronically exposed to UV-B avoid high and low temperature extremes to maximize activities of antioxidant enzymes. Fish chronically (two to three weeks) exposed to UV-B had increased reactive oxygen species (ROS)-induced damage to proteins and membranes, and reduced swimming performance at high (more than 26°C) temperatures. In an open field arena with a thermal gradient, chronically exposed fish avoided high and low temperature extremes compared with control fish. Additionally, both control and chronically exposed fish showed slower voluntary swimming speeds in the presence of UV-B. We suggest that in the presence of UV-B fish may reduce muscular activity to minimize intrinsic ROS production. Our data show that the interaction between UV-B and temperature determines movement and microhabitat selection of fish, which is therefore of ecological importance particularly in anthropogenically modified environments. PMID:27531156

  16. Selenium status affects selenoprotein expression, reproduction, and F₁ generation locomotor activity in zebrafish (Danio rerio).

    Science.gov (United States)

    Penglase, Sam; Hamre, Kristin; Rasinger, Josef D; Ellingsen, Staale

    2014-06-14

    Se is an essential trace element, and is incorporated into selenoproteins which play important roles in human health. Mammalian selenoprotein-coding genes are often present as paralogues in teleost fish, and it is unclear whether the expression patterns or functions of these fish paralogues reflect their mammalian orthologues. Using the model species zebrafish (Danio rerio; ZF), we aimed to assess how dietary Se affects key parameters in Se metabolism and utilisation including glutathione peroxidase (GPX) activity, the mRNA expression of key Se-dependent proteins (gpx1a, gpx1b, sepp1a and sepp1b), oxidative status, reproductive success and F1 generation locomotor activity. From 27 d until 254 d post-fertilisation, ZF were fed diets with graded levels of Se ranging from deficient ( levels were lowest when dietary Se levels (0·3 mg/kg) resulted in the maximum growth of ZF, and a proposed bimodal mechanism in response to Se status below and above this dietary Se level was identified. The expression of the sepp1 paralogues differed, with only sepp1a responding to Se status. High dietary Se supplementation (30 mg/kg) decreased reproductive success, while the offspring of ZF fed above 0·3 mg Se/kg diet had lower locomotor activity than the other groups. Overall, the novel finding of low selenoprotein expression and activity coinciding with maximum body growth suggests that even small Se-induced variations in redox status may influence cellular growth rates.

  17. Tissue uptake, distribution and elimination of {sup 14}C-PFOA in zebrafish (Danio rerio)

    Energy Technology Data Exchange (ETDEWEB)

    Ulhaq, Mazhar [Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, SE-750 07 Uppsala (Sweden); Sundström, Maria [Environmental Chemistry Unit, Department of Materials and Environmental Chemistry, Stockholm University, SE-106 91 Stockholm (Sweden); Larsson, Pia; Gabrielsson, Johan [Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, SE-750 07 Uppsala (Sweden); Bergman, Åke [Environmental Chemistry Unit, Department of Materials and Environmental Chemistry, Stockholm University, SE-106 91 Stockholm (Sweden); Norrgren, Leif [Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, SE-750 07 Uppsala (Sweden); Örn, Stefan, E-mail: Stefan.Orn@slu.se [Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, SE-750 07 Uppsala (Sweden)

    2015-06-15

    Highlights: • Bioconcentration of PFOA at steady-state was approximately 20–30 times. • High concentrations were observed in bile and intestines implying enterohepatic circulation. • PFOA accumulated in oocytes indicating maternal transfer. - Abstract: Perfluorooctanoic acid (PFOA) is a long-chain perfluorinated chemical that has been shown to be non-degradable and persistent in the environment. Laboratory studies on bioconcentration and compound-specific tissue distribution in fish can be valuable for prediction of the persistence and environmental effects of the chemicals. In the present study male and female zebrafish (Danio rerio) were continuously exposed to 10 μg/L of radiolabeled perfluorooctanoic acid ({sup 14}C-PFOA) for 40 days, after which the exposed fish were transferred to fresh clean water for another 80 days wash-out period. At defined periodic intervals during the uptake and wash-out, fish were sampled for liquid scintillation counting and whole body autoradiography to profile the bioconcentration and tissue distribution of PFOA. The steady-state concentration of {sup 14}C-PFOA in the zebrafish was reached within 20–30 days of exposure. The concentration-time course of {sup 14}C-PFOA displayed a bi-exponential decline during washout, with a terminal half-life of approximately 13–14 days. At steady-state the bioconcentration of {sup 14}C-PFOA into whole-body fish was approximately 20–30 times greater than that of the exposure concentration, with no differences between females and males. The bioconcentration factors for liver and intestine were approximately 100-fold of the exposure medium, while in brain, ovary and gall bladder the accumulation factors were in the range 15–20. Whole-body autoradiograms confirmed the highest labeling of PFOA in bile and intestines, which implies enterohepatic circulation of PFOA. The {sup 14}C-PFOA was also observed in maturing vitellogenic oocytes, suggesting chemical accumulation via yolk proteins

  18. Prolonged hypoxia increases survival even in Zebrafish (Danio rerio showing cardiac arrhythmia.

    Directory of Open Access Journals (Sweden)

    Renate Kopp

    Full Text Available Tolerance towards hypoxia is highly pronounced in zebrafish. In this study even beneficial effects of hypoxia, specifically enhanced survival of zebrafish larvae, could be demonstrated. This effect was actually more pronounced in breakdance mutants, which phenotypically show cardiac arrhythmia. Breakdance mutants (bre are characterized by chronically reduced cardiac output. Despite an about 50% heart rate reduction, they become adults, but survival rate significantly drops to 40%. Normoxic bre animals demonstrate increased hypoxia inducible factor 1 a (Hif-1α expression, which indicates an activated hypoxic signaling pathway. Consequently, cardiovascular acclimation, like cardiac hypertrophy and increased erythrocyte concentration, occurs. Thus, it was hypothesized, that under hypoxic conditions survival might be even more reduced. When bre mutants were exposed to hypoxic conditions, they surprisingly showed higher survival rates than under normoxic conditions and even reached wildtype values. In hypoxic wildtype zebrafish, survival yet exceeded normoxic control values. To specify physiological acclimation, cardiovascular and metabolic parameters were measured before hypoxia started (3 dpf, when the first differences in survival rate occurred (7 dpf and when survival rate plateaued (15 dpf. Hypoxic animals expectedly demonstrated Hif-1α accumulation and consequently enhanced convective oxygen carrying capacity. Moreover, bre animals showed a significantly enhanced heart rate under hypoxic conditions, which reached normoxic wildtype values. This improvement in convective oxygen transport ensured a sufficient oxygen and nutrient supply and was also reflected in the significantly higher mitochondrial activity. The highly optimized energy metabolism observed in hypoxic zebrafish larvae might be decisive for periods of higher energy demand due to organ development, growth and increased activity. However, hypoxia increased survival only during a

  19. Density-dependent processes in the life history of fishes: evidence from laboratory populations of zebrafish Danio rerio.

    Directory of Open Access Journals (Sweden)

    Charles R E Hazlerigg

    Full Text Available Population regulation is fundamental to the long-term persistence of populations and their responses to harvesting, habitat modification, and exposure to toxic chemicals. In fish and other organisms with complex life histories, regulation may involve density dependence in different life-stages and vital rates. We studied density dependence in body growth and mortality through the life-cycle of laboratory populations of zebrafish Danio rerio. When feed input was held constant at population-level (leading to resource limitation, body growth was strongly density-dependent in the late juvenile and adult phases of the life-cycle. Density dependence in mortality was strong during the early juvenile phase but declined thereafter and virtually ceased prior to maturation. Provision of feed in proportion to individual requirements (easing resource limitation removed density dependence in growth and substantially reduced density dependence in mortality, thus indicating that 'bottom-up' effects act on growth as well as mortality, but most strongly on growth. Both growth and mortality played an important role in population regulation, with density-dependent growth having the greater impact on population biomass while mortality had the greatest impact on numbers. We demonstrate a clear ontogenic pattern of change in density-dependent processes within populations of a very small (maximum length 5 mm fish, maintained in constant homogeneous laboratory conditions. The patterns are consistent with those distilled from studies on wild fish populations, indicating the presence of broad ontogenic patterns in density-dependent processes that are invariant to maximum body size and hold in homogeneous laboratory, as well as complex natural environments.

  20. The effect of fasting and refeeding on mRNA expression of PepT1 and gastrointestinal hormones regulating digestion and food intake in zebrafish (Danio rerio).

    Science.gov (United States)

    Koven, William; Schulte, Patricia

    2012-12-01

    In vertebrates, a significant part of ingested protein is absorbed as di- and tripeptides through a brush border membrane proton/oligopeptide transporter protein called PepT1. The aim of the present study was to determine the effect of short-term food deprivation and refeeding in adult zebrafish (Danio rerio) on gastrointestinal mRNA expression of PepT1 as well as on the satiety hormones cholecystokinin (CCK), gastrin-releasing peptide (GRP) and ghrelin (GHR) in order to elucidate a potential mechanism driving compensatory growth. Sixty adult zebrafish were stocked in a 40-L aquarium and fed daily a commercial flake diet to satiation for 10 days where the digestive tracts (DT) of sampled fish (n = 5) were dissected out. Samplings were repeated following 1, 2 and 5 days of food deprivation and after 1, 2 and 5 days of refeeding. The RNA was extracted from all sampled DTs and analyzed by quantitative real-time PCR for the mRNA expression of PepT1, rRNA 18S, CCK, GRP and GHR. PepT1 mRNA expression increased with successive refeedings reaching a level approximately 8 times higher than pre-fast levels. CCK, GRP and GHR mRNA levels also decreased during fasting, but increased only to pre-fasting levels with refeeding. Overall, the results suggest that PepT1 may be a contributing mechanism to compensatory growth that could influence CCK secretion and GRP and GHR activity.

  1. Reversibility of endocrine disruption in zebrafish (Danio rerio) after discontinued exposure to the estrogen 17α-ethinylestradiol

    International Nuclear Information System (INIS)

    The aim of the present study was to investigate the persistence of the feminizing effects of discontinued 17α-ethinylestradiol (EE2) exposure on zebrafish (Danio rerio). An exposure scenario covering the sensitive phase of sexual differentiation, as well as final gonad maturation was chosen to examine the estrogenic effects on sexual development of zebrafish. Two exposure scenarios were compared: continuous exposure to environmentally relevant concentrations (0.1–10 ng/L EE2) up to 100 days post-hatch (dph) and developmental exposure up to 60 dph, followed by 40 days of depuration in clean water. The persistence of effects was investigated at different biological organization levels from mRNA to population-relevant endpoints to cover a broad range of important parameters. EE2 had a strong feminizing and inhibiting effect on the sexual development of zebrafish. Brain aromatase (cyp19b) mRNA expression showed no clear response, but vitellogenin levels were significantly elevated, gonad maturation and body growth were inhibited in both genders, and sex ratios were skewed towards females and undifferentiated individuals. To a large extent, all of these effects were reversed after 40 days of recovery, leading to the conclusion that exposure to the estrogen EE2 results in very strong, but reversible underdevelopment and feminization of zebrafish. The present study is the first to show this reversibility at different levels of organization, which gives better insight into the mechanistic basis of estrogenic effects in zebrafish. - Highlights: • Zebrafish were exposed to 17α-ethinylestradiol during their sexual differentiation. • Reversibility of effects was investigated after depuration of 40 days. • Morphological and physiological parameters were compared. • Zebrafish were able to recover at all different levels from mRNA to population

  2. Reversibility of endocrine disruption in zebrafish (Danio rerio) after discontinued exposure to the estrogen 17α-ethinylestradiol

    Energy Technology Data Exchange (ETDEWEB)

    Baumann, Lisa, E-mail: lisa.baumann@vetsuisse.unibe.ch [Centre for Fish and Wildlife Health, Vetsuisse Faculty, University of Bern, PO Box 8466, CH-3001 Bern (Switzerland); Aquatic Ecology and Toxicology Section, Centre for Organismal Studies, University of Heidelberg, Im Neuenheimer Feld 230, D-69120 Heidelberg (Germany); Knörr, Susanne, E-mail: susanne.knoerr@gmx.de [Aquatic Ecology and Toxicology Section, Centre for Organismal Studies, University of Heidelberg, Im Neuenheimer Feld 230, D-69120 Heidelberg (Germany); Keiter, Susanne, E-mail: susanne.keiter@cos.uni-heidelberg.de [Aquatic Ecology and Toxicology Section, Centre for Organismal Studies, University of Heidelberg, Im Neuenheimer Feld 230, D-69120 Heidelberg (Germany); Rehberger, Kristina, E-mail: k.rehberger@stud.uni-heidelberg.de [Aquatic Ecology and Toxicology Section, Centre for Organismal Studies, University of Heidelberg, Im Neuenheimer Feld 230, D-69120 Heidelberg (Germany); Volz, Sina, E-mail: s.volz@stud.uni-heidelberg.de [Aquatic Ecology and Toxicology Section, Centre for Organismal Studies, University of Heidelberg, Im Neuenheimer Feld 230, D-69120 Heidelberg (Germany); Schiller, Viktoria, E-mail: schiller@molbiotech.rwth-aachen.de [Fraunhofer Institute for Molecular Biology and Applied Ecology, Forckenbeckstr. 6, D-52074 Aachen (Germany); Fenske, Martina, E-mail: martina.fenske@ime.fraunhofer.de [Fraunhofer Institute for Molecular Biology and Applied Ecology, Forckenbeckstr. 6, D-52074 Aachen (Germany); Holbech, Henrik, E-mail: hol@biology.sdu.dk [Department of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M (Denmark); Segner, Helmut, E-mail: helmut.segner@vetsuisse.unibe.ch [Centre for Fish and Wildlife Health, Vetsuisse Faculty, University of Bern, PO Box 8466, CH-3001 Bern (Switzerland); Braunbeck, Thomas, E-mail: braunbeck@uni-hd.de [Aquatic Ecology and Toxicology Section, Centre for Organismal Studies, University of Heidelberg, Im Neuenheimer Feld 230, D-69120 Heidelberg (Germany)

    2014-08-01

    The aim of the present study was to investigate the persistence of the feminizing effects of discontinued 17α-ethinylestradiol (EE2) exposure on zebrafish (Danio rerio). An exposure scenario covering the sensitive phase of sexual differentiation, as well as final gonad maturation was chosen to examine the estrogenic effects on sexual development of zebrafish. Two exposure scenarios were compared: continuous exposure to environmentally relevant concentrations (0.1–10 ng/L EE2) up to 100 days post-hatch (dph) and developmental exposure up to 60 dph, followed by 40 days of depuration in clean water. The persistence of effects was investigated at different biological organization levels from mRNA to population-relevant endpoints to cover a broad range of important parameters. EE2 had a strong feminizing and inhibiting effect on the sexual development of zebrafish. Brain aromatase (cyp19b) mRNA expression showed no clear response, but vitellogenin levels were significantly elevated, gonad maturation and body growth were inhibited in both genders, and sex ratios were skewed towards females and undifferentiated individuals. To a large extent, all of these effects were reversed after 40 days of recovery, leading to the conclusion that exposure to the estrogen EE2 results in very strong, but reversible underdevelopment and feminization of zebrafish. The present study is the first to show this reversibility at different levels of organization, which gives better insight into the mechanistic basis of estrogenic effects in zebrafish. - Highlights: • Zebrafish were exposed to 17α-ethinylestradiol during their sexual differentiation. • Reversibility of effects was investigated after depuration of 40 days. • Morphological and physiological parameters were compared. • Zebrafish were able to recover at all different levels from mRNA to population.

  3. The flexural stiffness of superficial neuromasts in the zebrafish (Danio rerio) lateral line.

    Science.gov (United States)

    McHenry, Matthew J; van Netten, Sietse M

    2007-12-01

    Superficial neuromasts are structures that detect water flow on the surface of the body of fish and amphibians. As a component of the lateral line system, these receptors are distributed along the body, where they sense flow patterns that mediate a wide variety of behaviors. Their ability to detect flow is governed by their structural properties, yet the micromechanics of superficial neuromasts are not well understood. The aim of this study was to examine these mechanics in zebrafish (Danio rerio) larvae by measuring the flexural stiffness of individual neuromasts. Each neuromast possesses a gelatinous cupula that is anchored to hair cells by kinocilia. Using quasi-static bending tests of the proximal region of the cupula, we found that flexural stiffness is proportional to the number of hair cells, and consequently the number of kinocilia, within a neuromast. From this relationship, the flexural stiffness of an individual kinocilium was found to be 2.4 x 10(-20) N m2. Using this value, we estimate that the 11 kinocilia in an average cupula generate more than four-fifths of the total flexural stiffness in the proximal region. The relatively minor contribution of the cupular matrix may be attributed to its highly compliant material composition (Young's modulus of approximately 21 Pa). The distal tip of the cupula is entirely composed of this material and is consequently predicted to be at least an order of magnitude more flexible than the proximal region. These findings suggest that the transduction of flow by a superficial neuromast depends on structural dynamics that are dominated by the number and height of kinocilia.

  4. Selenium status affects selenoprotein expression, reproduction, and F₁ generation locomotor activity in zebrafish (Danio rerio).

    Science.gov (United States)

    Penglase, Sam; Hamre, Kristin; Rasinger, Josef D; Ellingsen, Staale

    2014-06-14

    Se is an essential trace element, and is incorporated into selenoproteins which play important roles in human health. Mammalian selenoprotein-coding genes are often present as paralogues in teleost fish, and it is unclear whether the expression patterns or functions of these fish paralogues reflect their mammalian orthologues. Using the model species zebrafish (Danio rerio; ZF), we aimed to assess how dietary Se affects key parameters in Se metabolism and utilisation including glutathione peroxidase (GPX) activity, the mRNA expression of key Se-dependent proteins (gpx1a, gpx1b, sepp1a and sepp1b), oxidative status, reproductive success and F1 generation locomotor activity. From 27 d until 254 d post-fertilisation, ZF were fed diets with graded levels of Se ranging from deficient ( < 0·10 mg/kg) to toxic (30 mg/kg). The mRNA expression of gpx1a and gpx1b and GPX activity responded in a similar manner to changes in Se status. GPX activity and mRNA levels were lowest when dietary Se levels (0·3 mg/kg) resulted in the maximum growth of ZF, and a proposed bimodal mechanism in response to Se status below and above this dietary Se level was identified. The expression of the sepp1 paralogues differed, with only sepp1a responding to Se status. High dietary Se supplementation (30 mg/kg) decreased reproductive success, while the offspring of ZF fed above 0·3 mg Se/kg diet had lower locomotor activity than the other groups. Overall, the novel finding of low selenoprotein expression and activity coinciding with maximum body growth suggests that even small Se-induced variations in redox status may influence cellular growth rates. PMID:24666596

  5. Impacts of 17α-ethynylestradiol exposure on metabolite profiles of zebrafish (Danio rerio) liver cells

    International Nuclear Information System (INIS)

    Highlights: ► We apply NMR-based metabolomics to study responses of ZFL cells exposed to EE2. ► The metabolomics approach has capability to capture cellular response to exposure. ► The analysis provides detailed molecular information on chemical's mode of action. ► Cellular metabolomics may have application for screening chemical exposure/toxicity. -- Abstract: Endocrine disrupting chemicals (EDCs) that are frequently detected in bodies of water downstream from sewage treatment facilities can have adverse impacts on fish and other aquatic organisms. To properly assess risk(s) from EDCs, tools are needed that can establish linkages from chemical exposures to adverse outcomes. Traditional methods of testing chemical exposure and toxicity using experimental animals are excessively resource- and time-consuming. In line with EPA's goal of reducing animal use in testing, these traditional screening methods may not be sustainable in the long term, given the ever increasing number of chemicals that must be tested for safety. One of the most promising ways to reduce costs and increase throughput is to use cell cultures instead of experimental animals. In accordance with National Research Council's vision on 21st century toxicity testing, we have developed a cell culture-based metabolomics approach for this application. Using a zebrafish (Danio rerio) liver cell line (ZFL), we have applied NMR-based metabolomics to investigate responses of ZFL cells exposed to 17α-ethynylestradiol (EE2). This analysis showed that metabolite changes induced by EE2 exposure agree well with known impacts of estrogens on live fish. The results of this study demonstrate the potential of cell-based metabolomics to assess chemical exposure and toxicity for regulatory application

  6. Impacts of 17α-ethynylestradiol exposure on metabolite profiles of zebrafish (Danio rerio) liver cells

    Energy Technology Data Exchange (ETDEWEB)

    Teng, Quincy, E-mail: teng.quincy@epa.gov [National Exposure Research Laboratory, U.S. Environmental Protection Agency, 960 College Station Road, Athens, GA 30605 (United States); Ekman, Drew R., E-mail: ekman.drew@epa.gov [National Exposure Research Laboratory, U.S. Environmental Protection Agency, 960 College Station Road, Athens, GA 30605 (United States); Huang, Wenlin, E-mail: whuang2@ccny.cuny.edu [National Exposure Research Laboratory, U.S. Environmental Protection Agency, 960 College Station Road, Athens, GA 30605 (United States); Collette, Timothy W., E-mail: collette.tim@epa.gov [National Exposure Research Laboratory, U.S. Environmental Protection Agency, 960 College Station Road, Athens, GA 30605 (United States)

    2013-04-15

    Highlights: ► We apply NMR-based metabolomics to study responses of ZFL cells exposed to EE2. ► The metabolomics approach has capability to capture cellular response to exposure. ► The analysis provides detailed molecular information on chemical's mode of action. ► Cellular metabolomics may have application for screening chemical exposure/toxicity. -- Abstract: Endocrine disrupting chemicals (EDCs) that are frequently detected in bodies of water downstream from sewage treatment facilities can have adverse impacts on fish and other aquatic organisms. To properly assess risk(s) from EDCs, tools are needed that can establish linkages from chemical exposures to adverse outcomes. Traditional methods of testing chemical exposure and toxicity using experimental animals are excessively resource- and time-consuming. In line with EPA's goal of reducing animal use in testing, these traditional screening methods may not be sustainable in the long term, given the ever increasing number of chemicals that must be tested for safety. One of the most promising ways to reduce costs and increase throughput is to use cell cultures instead of experimental animals. In accordance with National Research Council's vision on 21st century toxicity testing, we have developed a cell culture-based metabolomics approach for this application. Using a zebrafish (Danio rerio) liver cell line (ZFL), we have applied NMR-based metabolomics to investigate responses of ZFL cells exposed to 17α-ethynylestradiol (EE2). This analysis showed that metabolite changes induced by EE2 exposure agree well with known impacts of estrogens on live fish. The results of this study demonstrate the potential of cell-based metabolomics to assess chemical exposure and toxicity for regulatory application.

  7. Ecotoxicity of ketoprofen, diclofenac, atenolol and their photolysis byproducts in zebrafish (Danio rerio)

    Energy Technology Data Exchange (ETDEWEB)

    Diniz, M.S., E-mail: mesd@fct.unl.pt [REQUIMTE/CQFB, Chemistry Department, FCT, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Salgado, R., E-mail: r.salgado@campus.fct.unl.pt [REQUIMTE/CQFB, Chemistry Department, FCT, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); ESTS-IPS, Escola Superior de Tecnologia de Setúbal do Instituto Politécnico de Setúbal, Rua Vale de Chaves, Campus do IPS, Estefanilha, 2910-761 Setúbal (Portugal); Pereira, V.J., E-mail: vanessap@itqb.unl.pt [Instituto de Biologia Experimental e Tecnológica (IBET), Av. da República (EAN), 2784-505 Oeiras (Portugal); Instituto de Tecnologia Química e Biológica (ITQB)—Universidade Nova de Lisboa (UNL), Estação Agronómica Nacional, Av. da República, 2780-157 Oeiras (Portugal); Carvalho, G., E-mail: gs.carvalho@fct.unl.pt [REQUIMTE/CQFB, Chemistry Department, FCT, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Instituto de Biologia Experimental e Tecnológica (IBET), Av. da República (EAN), 2784-505 Oeiras (Portugal); Oehmen, A., E-mail: a.oehmen@fct.unl.pt [REQUIMTE/CQFB, Chemistry Department, FCT, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Reis, M.A.M., E-mail: amr@fct.unl.pt [REQUIMTE/CQFB, Chemistry Department, FCT, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Noronha, J.P., E-mail: jpnoronha@fct.unl.pt [REQUIMTE/CQFB, Chemistry Department, FCT, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal)

    2015-02-01

    The occurrence of pharmaceutical compounds in wastewater treatment plants and surface waters has been detected worldwide, constituting a potential risk for aquatic ecosystems. Adult zebrafish, of both sexes, were exposed to three common pharmaceutical compounds (atenolol, ketoprofen and diclofenac) and their UV photolysis by-products over seven days. The results show that diclofenac was removed to concentrations < LOD after 5 min of UV irradiation. The oxidative stress response of zebrafish to pharmaceuticals and their photolysis by-products was evaluated through oxidative stress enzymes (glutathione-S-transferase, catalase, superoxide dismutase) and lipid peroxidation. Results suggest that the photolysis by-products of diclofenac were more toxic than those from the other compounds tested, showing an increase in GST and CAT levels, which are also supported by higher MDA levels. Overall, the toxicity of waters containing atenolol and ketoprofen was reduced after the parent compounds were transformed by photolysis, whereas the toxicity increased significantly from the by-products generated through diclofenac photolysis. Therefore, diclofenac photolysis would possibly necessitate higher irradiation time to ensure that the associated by-products are completely degraded to harmless form(s). - Highlights: • Toxicity evaluated for 3 common pharmaceuticals (atenolol, ketoprofen and diclofenac). • Toxicity assessed for the pharmaceuticals and UV photolysis by-products in zebrafish. • Diclofenac photolysis by-products are more toxic than the parent compound. • Ketoprofen and atenolol show stronger oxidative stress response than by-products. • UV photolysis should ensure full removal of diclofenac metabolites to avoid toxicity.

  8. Lipidomics and H218O labeling techniques reveal increased remodeling of DHA-containing membrane phospholipids associated with abnormal locomotor responses in α-tocopherol deficient zebrafish (danio rerio) embryos

    OpenAIRE

    McDougall, Melissa Q.; Jaewoo Choi; Stevens, Jan F.; Lisa Truong; Tanguay, Robert L.; Traber, Maret G.

    2016-01-01

    We hypothesized that vitamin E (α-tocopherol) is required by the developing embryonic brain to prevent depletion of highly polyunsaturated fatty acids, especially docosahexaenoic acid (DHA, 22:6), the loss of which we predicted would underlie abnormal morphological and behavioral outcomes. Therefore, we fed adult 5D zebrafish (Danio rerio) defined diets without (E−) or with added α-tocopherol (E+, 500 mg RRR-α-tocopheryl acetate/kg diet) for a minimum of 80 days, and then spawned them to obta...

  9. Persistence of endocrine disruption in zebrafish (Danio rerio) after discontinued exposure to the androgen 17β-trenbolone.

    Science.gov (United States)

    Baumann, Lisa; Knörr, Susanne; Keiter, Susanne; Nagel, Tina; Rehberger, Kristina; Volz, Sina; Oberrauch, Sophia; Schiller, Viktoria; Fenske, Martina; Holbech, Henrik; Segner, Helmut; Braunbeck, Thomas

    2014-11-01

    The aim of the present study was to investigate the effects of the androgenic endocrine disruptor 17β-trenbolone on the sexual development of zebrafish (Danio rerio) with special emphasis on the question of whether adverse outcomes of developmental exposure are reversible or persistent. An exposure scenario including a recovery phase was chosen to assess the potential reversibility of androgenic effects. Zebrafish were exposed to environmentally relevant concentrations of 17β-trenbolone (1 ng/L-30 ng/L) from fertilization until completion of gonad sexual differentiation (60 d posthatch). Thereafter, exposure was either followed by 40 d of recovery in clean water or continued until 100 d posthatch, the age when zebrafish start being able to reproduce. Fish exposed for 100 d to 10 ng/L or 30 ng/L 17β-trenbolone were masculinized at different biological effect levels, as evidenced from a concentration-dependent shift of the sex ratio toward males as well as a significantly increased maturity of testes. Gonad morphological masculinization occurred in parallel with decreased vitellogenin concentrations in both sexes. Changes of brain aromatase (cyp19b) mRNA expression showed no consistent trend with respect to either exposure duration or concentration. Gonad morphological masculinization as well as the decrease of vitellogenin persisted after depuration over 40 d in clean water. This lack of recovery suggests that androgenic effects on sexual development of zebrafish are irreversible. PMID:25070268

  10. The paracrine effect of exogenous growth hormone alleviates dysmorphogenesis caused by tbx5 deficiency in zebrafish (Danio rerio embryos

    Directory of Open Access Journals (Sweden)

    Tsai Tzu-Chun

    2012-07-01

    Full Text Available Abstract Background Dysmorphogenesis and multiple organ defects are well known in zebrafish (Danio rerio embryos with T-box transcription factor 5 (tbx5 deficiencies, mimicking human Holt-Oram syndrome. Methods Using an oligonucleotide-based microarray analysis to study the expression of special genes in tbx5 morphants, we demonstrated that GH and some GH-related genes were markedly downregulated. Zebrafish embryos microinjected with tbx5-morpholino (MO antisense RNA and mismatched antisense RNA in the 1-cell stage served as controls, while zebrafish embryos co-injected with exogenous growth hormone (GH concomitant with tbx5-MO comprised the treatment group. Results The attenuating effects of GH in tbx5-MO knockdown embryos were quantified and observed at 24, 30, 48, 72, and 96 h post-fertilization. Though the understanding of mechanisms involving GH in the tbx5 functioning complex is limited, exogenous GH supplied to tbx5 knockdown zebrafish embryos is able to enhance the expression of downstream mediators in the GH and insulin-like growth factor (IGF-1 pathway, including igf1, ghra, and ghrb, and signal transductors (erk1, akt2, and eventually to correct dysmorphogenesis in various organs including the heart and pectoral fins. Supplementary GH also reduced apoptosis as determined by a TUNEL assay and decreased the expression of apoptosis-related genes and proteins (bcl2 and bad according to semiquantitative reverse-transcription polymerase chain reaction and immunohistochemical analysis, respectively, as well as improving cell cycle-related genes (p27 and cdk2 and cardiomyogenetic genes (amhc, vmhc, and cmlc2. Conclusions Based on our results, tbx5 knockdown causes a pseudo GH deficiency in zebrafish during early embryonic stages, and supplementation of exogenous GH can partially restore dysmorphogenesis, apoptosis, cell growth inhibition, and abnormal cardiomyogenesis in tbx5 knockdown zebrafish in a paracrine manner.

  11. Sex specific response in cholesterol level in zebrafish (Danio rerio) after long-term exposure of difenoconazole

    International Nuclear Information System (INIS)

    Difenoconazole is a widely used triazole fungicide, its extensive application may potentially cause toxic effects on non-target organisms. To investigate the effect of difenoconazole on cholesterol content and related mechanism, adult zebrafish were exposed to environmental related dosage (0.1, 10 and 500 μg/L) difenoconazole. The body weight and hepatic total cholesterol (TCHO) level was tested at 7, 15 and 30 days post exposure (dpe). The expressions of eight cholesterol synthesis genes and one cholesterol metabolism gene were assessed via Quantitative PCR method. The significant decrease of TCHO level in male zebrafish liver was observed at 15 and 30 dpe, which was accompanied by apparent hepatic cholesterol-genesis genes expression decline. In comparison with males, female zebrafish showed different transcription modification of tested genes, and the cholesterol content maintain normal level during the whole exposure. - Highlights: • Difenoconazle could reduce TCHO level in male zebrafish liver. • Difenoconazole could inhibit sterol-genesis genes expression in male zebrafish. • Female zebrafish didn't show obvious change of TCHO level after exposure. • Difenoconazole could inhibit body weight of both male and female zebrafish. - Difenoconazle could reduce cholesterol level and sterol-genesis genes expression in male zebrafish. While female zebrafish showed no obvious cholesterol content change during exposure

  12. Functional characterization of a full length pregnane X receptor, expression in vivo, and identification of PXR alleles, in Zebrafish (Danio rerio)

    Energy Technology Data Exchange (ETDEWEB)

    Bainy, Afonso C.D. [Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543 (United States); Departamento de Bioquímica, CCB, Universidade Federal de Santa Catarina, Florianópolis, SC 88040-900 (Brazil); Kubota, Akira; Goldstone, Jared V. [Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543 (United States); Lille-Langøy, Roger [Department of Biology, University of Bergen, N-5020 Bergen (Norway); Karchner, Sibel I. [Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543 (United States); Celander, Malin C. [Department of Biological and Environmental Sciences, University of Gothenburg, SE 405 30 Göteborg (Sweden); Hahn, Mark E. [Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543 (United States); Goksøyr, Anders [Department of Biology, University of Bergen, N-5020 Bergen (Norway); Stegeman, John J., E-mail: jstegeman@whoi.edu [Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543 (United States)

    2013-10-15

    Highlights: •Full-length pxr has been cloned from zebrafish. •Alleles of pxr were identified in zebrafish. •Full length Pxr was activated less strongly than ligand binding domain in cell-based reporter assays. •High levels of pxr expression were found in eye and brain as well as in liver. •TCPOBOP and PB did not significantly alter expression of pxr in liver. -- Abstract: The pregnane X receptor (PXR) (nuclear receptor NR1I2) is a ligand activated transcription factor, mediating responses to diverse xenobiotic and endogenous chemicals. The properties of PXR in fish are not fully understood. Here we report on cloning and characterization of full-length PXR of zebrafish, Danio rerio, and pxr expression in vivo. Initial efforts gave a cDNA encoding a 430 amino acid protein identified as zebrafish pxr by phylogenetic and synteny analysis. The sequence of the cloned Pxr DNA binding domain (DBD) was highly conserved, with 74% identity to human PXR-DBD, while the ligand-binding domain (LBD) of the cloned sequence was only 44% identical to human PXR-LBD. Sequence variation among clones in the initial effort prompted sequencing of multiple clones from a single fish. There were two prominent variants, one sequence with S183, Y218 and H383 and the other with I183, C218 and N383, which we designate as alleles pxr*1 (nr1i2*1) and pxr*2 (nr1i2*2), respectively. In COS-7 cells co-transfected with a PXR-responsive reporter gene, the full-length Pxr*1 (the more common variant) was activated by known PXR agonists clotrimazole and pregnenolone 16α-carbonitrile but to a lesser extent than the full-length human PXR. Activation of full-length Pxr*1 was only 10% of that with the Pxr*1 LBD. Quantitative real time PCR analysis showed prominent expression of pxr in liver and eye, as well as brain and intestine of adult zebrafish. The pxr was expressed in heart and kidney at levels similar to that in intestine. The expression of pxr in liver was weakly induced by ligands for

  13. iPhone® applications as versatile video tracking tools to analyze behavior in zebrafish (Danio rerio).

    Science.gov (United States)

    Pittman, Julian T; Ichikawa, Katie M

    2013-05-01

    Zebrafish (Danio rerio) are emerging as a promising model organism for experimental studies relevant to biological psychiatry. The objective of this study was to develop a novel video-based movement tracking and analysis system to quantify behavioral changes following psychoactive drug exposure in zebrafish. We assessed the effects of withdrawal from chronic ethanol exposure, and subsequent administration of fluoxetine (Prozac®), buspirone (Buspar®), and diazepam (Valium) using two behavioral paradigms; the Novel Tank Diving Test and the Light/Dark Choice Assay. A video tracking system was developed using two Apple® applications (Apps) to quantify these behaviors. Data from zebrafish exposed to the above treatments are presented in this paper not only to exemplify behavioral alterations associated with chronic exposure, but also more importantly, to validate the video tracking system. Following withdrawal from chronic ethanol exposure, zebrafish exhibited dose/time-dependent anxiogenic effects; including reduced exploration and freezing behavior in the Novel Tank Diving Test, and preference for the dark area for the Light/Dark Choice Assay. In contrast, the above drug treatments had significant anxiolytic effects. We have developed a simple and cost-effective method of measuring zebrafish behavioral responses. The iPhone® Apps outlined in this study offer numerous flexible methods of data acquisition; namely, ease of identification and tracking of multiple animals, tools for visualization of the tracks, and calculation of a range of analysis parameters. Furthermore, the limited amount of time required for interpretation of the video data makes this a powerful high-throughput tool with potential applications for pre-clinical drug development. PMID:23558086

  14. Assessment of Jatropha curcas L. biodiesel seed cake toxicity using the zebrafish (Danio rerio) embryo toxicity (ZFET) test.

    Science.gov (United States)

    Hallare, Arnold V; Ruiz, Paulo Lorenzo S; Cariño, J C Earl D

    2014-05-01

    Consequent to the growing demand for alternative sources of energy, the seeds from Jatropha curcas remain to be the favorite for biodiesel production. However, a significant volume of the residual organic mass (seed cake) is produced during the extraction process, which raises concerns on safe waste disposal. In the present study, we assessed the toxicity of J. curcas seed cake using the zebrafish (Danio rerio) embryotoxicity test. Within 1-h post-fertilization (hpf), the fertilized eggs were exposed to five mass concentrations of J. curcas seed cake and were followed through 24, 48, and 72 hpf. Toxicity was evaluated based on lethal endpoints induced on zebrafish embryos namely egg coagulation, non-formation of somites, and non-detachment of tail. The lowest concentration tested, 1 g/L, was not able to elicit toxicity on embryos whereas 100 % mortality (based also on lethal endpoints) was recorded at the highest concentration at 2.15 g/L. The computed LC50 for the J. curcas seed cake was 1.61 g/L. No further increase in mortality was observed in the succeeding time points (48 and 72 hpf) indicating that J. curcas seed cake exerted acute toxicity on zebrafish embryos. Sublethal endpoints (yolk sac and pericardial edema) were noted at 72 hpf in zebrafish embryos exposed to higher concentrations. The observed lethal endpoints induced on zebrafish embryos were discussed in relation to the active principles, notably, phorbol esters that have remained in the seed cake even after extraction.

  15. iPhone® applications as versatile video tracking tools to analyze behavior in zebrafish (Danio rerio).

    Science.gov (United States)

    Pittman, Julian T; Ichikawa, Katie M

    2013-05-01

    Zebrafish (Danio rerio) are emerging as a promising model organism for experimental studies relevant to biological psychiatry. The objective of this study was to develop a novel video-based movement tracking and analysis system to quantify behavioral changes following psychoactive drug exposure in zebrafish. We assessed the effects of withdrawal from chronic ethanol exposure, and subsequent administration of fluoxetine (Prozac®), buspirone (Buspar®), and diazepam (Valium) using two behavioral paradigms; the Novel Tank Diving Test and the Light/Dark Choice Assay. A video tracking system was developed using two Apple® applications (Apps) to quantify these behaviors. Data from zebrafish exposed to the above treatments are presented in this paper not only to exemplify behavioral alterations associated with chronic exposure, but also more importantly, to validate the video tracking system. Following withdrawal from chronic ethanol exposure, zebrafish exhibited dose/time-dependent anxiogenic effects; including reduced exploration and freezing behavior in the Novel Tank Diving Test, and preference for the dark area for the Light/Dark Choice Assay. In contrast, the above drug treatments had significant anxiolytic effects. We have developed a simple and cost-effective method of measuring zebrafish behavioral responses. The iPhone® Apps outlined in this study offer numerous flexible methods of data acquisition; namely, ease of identification and tracking of multiple animals, tools for visualization of the tracks, and calculation of a range of analysis parameters. Furthermore, the limited amount of time required for interpretation of the video data makes this a powerful high-throughput tool with potential applications for pre-clinical drug development.

  16. Mate competition and evolutionary outcomes in genetically modified zebrafish (Danio rerio).

    Science.gov (United States)

    Howard, Richard D; Rohrer, Karl; Liu, Yiyang; Muir, William M

    2015-05-01

    Demonstrating relationships between sexual selection mechanisms and trait evolution is central to testing evolutionary theory. Using zebrafish, we found that wild-type males possessed a significant advantage in mate competition over transgenic RFP Glofish® males. In mating trials, wild-type males were aggressively superior to transgenic males in male-male chases and male-female chases; as a result, wild-type males sired 2.5× as many young as did transgenic males. In contrast, an earlier study demonstrated that female zebrafish preferred transgenic males as mates when mate competition was excluded experimentally. We tested the evolutionary consequence of this conflict between sexual selection mechanisms in a long-term study. The predicted loss of the transgenic phenotype was confirmed. More than 18,500 adults collected from 18 populations across 15 generations revealed that the frequency of the transgenic phenotype declined rapidly and was eliminated entirely in all but one population. Fitness component data for both sexes indicated that only male mating success differed between wild-type and transgenic individuals. Our predictive demographic model based on fitness components closely matched the rate of transgenic phenotype loss observed in the long-term study, thereby supporting its utility for studies assessing evolutionary outcomes of escaped or released genetically modified animals. PMID:25873489

  17. Progestins alter photo-transduction cascade and circadian rhythm network in eyes of zebrafish (Danio rerio)

    Science.gov (United States)

    Zhao, Yanbin; Fent, Karl

    2016-02-01

    Environmental progestins are implicated in endocrine disruption in vertebrates. Additional targets that may be affected in organisms are poorly known. Here we report that progesterone (P4) and drospirenone (DRS) interfere with the photo-transduction cascade and circadian rhythm network in the eyes of zebrafish. Breeding pairs of adult zebrafish were exposed to P4 and DRS for 21 days with different measured concentrations of 7–742 ng/L and 99-13´650 ng/L, respectively. Of totally 10 key photo-transduction cascade genes analyzed, transcriptional levels of most were significantly up-regulated, or normal down-regulation was attenuated. Similarly, for some circadian rhythm genes, dose-dependent transcriptional alterations were also observed in the totally 33 genes analyzed. Significant alterations occurred even at environmental relevant levels of 7 ng/L P4. Different patterns were observed for these transcriptional alterations, of which, the nfil3 family displayed most significant changes. Furthermore, we demonstrate the importance of sampling time for the determination and interpretation of gene expression data, and put forward recommendations for sampling strategies to avoid false interpretations. Our results suggest that photo-transduction signals and circadian rhythm are potential targets for progestins. Further studies are required to assess alterations on the protein level, on physiology and behavior, as well as on implications in mammals.

  18. Gene expression changes in female zebrafish (Danio rerio) brain in response to acute exposure to methylmercury

    Science.gov (United States)

    Richter, Catherine A.; Garcia-Reyero, Natàlia; Martyniuk, Chris; Knoebl, Iris; Pope, Marie; Wright-Osment, Maureen K.; Denslow, Nancy D.; Tillitt, Donald E.

    2011-01-01

    Methylmercury (MeHg) is a potent neurotoxicant and endocrine disruptor that accumulates in aquatic systems. Previous studies have shown suppression of hormone levels in both male and female fish, suggesting effects on gonadotropin regulation in the brain. The gene expression profile in adult female zebrafish whole brain induced by acute (96 h) MeHg exposure was investigated. Fish were exposed by injection to 0 or 0.5(mu or u)g MeHg/g. Gene expression changes in the brain were examined using a 22,000-feature zebrafish microarray. At a significance level of pdevelopment and function, as well as lipid metabolism and molecular transport. These results support the involvement of oxidative stress and effects on protein structure in the mechanism of action of MeHg in the female brain. Future studies will compare the gene expression profile induced in response to MeHg with that induced by other toxicants and will investigate responsive genes as potential biomarkers of MeHg exposure.

  19. Progestins alter photo-transduction cascade and circadian rhythm network in eyes of zebrafish (Danio rerio)

    Science.gov (United States)

    Zhao, Yanbin; Fent, Karl

    2016-02-01

    Environmental progestins are implicated in endocrine disruption in vertebrates. Additional targets that may be affected in organisms are poorly known. Here we report that progesterone (P4) and drospirenone (DRS) interfere with the photo-transduction cascade and circadian rhythm network in the eyes of zebrafish. Breeding pairs of adult zebrafish were exposed to P4 and DRS for 21 days with different measured concentrations of 7-742 ng/L and 99-13´650 ng/L, respectively. Of totally 10 key photo-transduction cascade genes analyzed, transcriptional levels of most were significantly up-regulated, or normal down-regulation was attenuated. Similarly, for some circadian rhythm genes, dose-dependent transcriptional alterations were also observed in the totally 33 genes analyzed. Significant alterations occurred even at environmental relevant levels of 7 ng/L P4. Different patterns were observed for these transcriptional alterations, of which, the nfil3 family displayed most significant changes. Furthermore, we demonstrate the importance of sampling time for the determination and interpretation of gene expression data, and put forward recommendations for sampling strategies to avoid false interpretations. Our results suggest that photo-transduction signals and circadian rhythm are potential targets for progestins. Further studies are required to assess alterations on the protein level, on physiology and behavior, as well as on implications in mammals.

  20. Effects of urea on the olfactory reception in zebrafish (Danio rerio

    Directory of Open Access Journals (Sweden)

    Lorenzo Gallus

    2016-06-01

    Full Text Available The effects of uremia on human olfactory functions have been clinically evaluated in various studies, even if to date it is not completely clarified which uremic toxins mediate these processes. Surprisingly, the role of the main molecule involved in uremia, urea indeed, has not been adequately investigated as other possible molecules may also be involved in uremic anosmia. The effects of urea on the olfaction have been evaluated in some clinical studies, but this is the first attempt to determine a direct action of urea on the olfactory epithelium of a vertebrate. Danio rerio adults were exposed to urea in different experiments to assess the effects on olfactory sensitivity and signal transduction. The analysis of the swimming speed has been used to evaluate the response to hypoxanthine 3-N-oxide (H3NO, a molecule that is known to elicit an olfactory-mediated alarm reaction in D. rerio. The presence and distribution of the G protein alpha subunit coupled to the olfactory receptors (Gαolf has been immunohistochemically investigated in the olfactory epithelium of control and urea-exposed D. rerio. Our findings showed that urea alters the response to H3NO of D. rerio with a quite rapid and reversible effect that appears to be independent from a mere interference of urea on the receptor-ligand binding. The Gαolf protein resulted increases after urea treatment, suggesting an effect of urea on its expression or degradation.

  1. Regeneration of Zebrafish CNS: Adult Neurogenesis.

    Science.gov (United States)

    Ghosh, Sukla; Hui, Subhra Prakash

    2016-01-01

    Regeneration in the animal kingdom is one of the most fascinating problems that have allowed scientists to address many issues of fundamental importance in basic biology. However, we came to know that the regenerative capability may vary across different species. Among vertebrates, fish and amphibians are capable of regenerating a variety of complex organs through epimorphosis. Zebrafish is an excellent animal model, which can repair several organs like damaged retina, severed spinal cord, injured brain and heart, and amputated fins. The focus of the present paper is on spinal cord regeneration in adult zebrafish. We intend to discuss our current understanding of the cellular and molecular mechanism(s) that allows formation of proliferating progenitors and controls neurogenesis, which involve changes in epigenetic and transcription programs. Unlike mammals, zebrafish retains radial glia, a nonneuronal cell type in their adult central nervous system. Injury induced proliferation involves radial glia which proliferate, transcribe embryonic genes, and can give rise to new neurons. Recent technological development of exquisite molecular tools in zebrafish, such as cell ablation, lineage analysis, and novel and substantial microarray, together with advancement in stem cell biology, allowed us to investigate how progenitor cells contribute to the generation of appropriate structures and various underlying mechanisms like reprogramming.

  2. Regeneration of Zebrafish CNS: Adult Neurogenesis

    Directory of Open Access Journals (Sweden)

    Sukla Ghosh

    2016-01-01

    Full Text Available Regeneration in the animal kingdom is one of the most fascinating problems that have allowed scientists to address many issues of fundamental importance in basic biology. However, we came to know that the regenerative capability may vary across different species. Among vertebrates, fish and amphibians are capable of regenerating a variety of complex organs through epimorphosis. Zebrafish is an excellent animal model, which can repair several organs like damaged retina, severed spinal cord, injured brain and heart, and amputated fins. The focus of the present paper is on spinal cord regeneration in adult zebrafish. We intend to discuss our current understanding of the cellular and molecular mechanism(s that allows formation of proliferating progenitors and controls neurogenesis, which involve changes in epigenetic and transcription programs. Unlike mammals, zebrafish retains radial glia, a nonneuronal cell type in their adult central nervous system. Injury induced proliferation involves radial glia which proliferate, transcribe embryonic genes, and can give rise to new neurons. Recent technological development of exquisite molecular tools in zebrafish, such as cell ablation, lineage analysis, and novel and substantial microarray, together with advancement in stem cell biology, allowed us to investigate how progenitor cells contribute to the generation of appropriate structures and various underlying mechanisms like reprogramming.

  3. Regeneration of Zebrafish CNS: Adult Neurogenesis

    Science.gov (United States)

    Ghosh, Sukla; Hui, Subhra Prakash

    2016-01-01

    Regeneration in the animal kingdom is one of the most fascinating problems that have allowed scientists to address many issues of fundamental importance in basic biology. However, we came to know that the regenerative capability may vary across different species. Among vertebrates, fish and amphibians are capable of regenerating a variety of complex organs through epimorphosis. Zebrafish is an excellent animal model, which can repair several organs like damaged retina, severed spinal cord, injured brain and heart, and amputated fins. The focus of the present paper is on spinal cord regeneration in adult zebrafish. We intend to discuss our current understanding of the cellular and molecular mechanism(s) that allows formation of proliferating progenitors and controls neurogenesis, which involve changes in epigenetic and transcription programs. Unlike mammals, zebrafish retains radial glia, a nonneuronal cell type in their adult central nervous system. Injury induced proliferation involves radial glia which proliferate, transcribe embryonic genes, and can give rise to new neurons. Recent technological development of exquisite molecular tools in zebrafish, such as cell ablation, lineage analysis, and novel and substantial microarray, together with advancement in stem cell biology, allowed us to investigate how progenitor cells contribute to the generation of appropriate structures and various underlying mechanisms like reprogramming. PMID:27382491

  4. Nitrogenous Waste Handling by Larval Zebrafish Danio rerio in Alkaline Water.

    Science.gov (United States)

    Kumai, Yusuke; Harris, Jessica; Al-Rewashdy, Hasanen; Kwong, Raymond W M; Perry, Steve F

    2015-01-01

    Although adult fish excrete their nitrogenous waste primarily as ammonia, larval fish may excrete a higher proportion as urea, an evolutionary strategy that lessens nitrogenous waste toxicity during early development. Previous studies firmly established that ammonia excretion is inhibited in adult fish acutely exposed to alkaline water. This study was designed to test the hypothesis that total nitrogen excretion is maintained in larval zebrafish raised in alkaline water (pH ∼ 10.0) as a result of compensatory adjustments to urea and/or ammonia transport pathways. Raising zebrafish in alkaline water from 0 to 4 d postfertilization (dpf) reduced ammonia excretion at 4 dpf, whereas urea excretion was elevated by 141%. The increase in urea excretion at 4 dpf served to maintain total nitrogen excretion constant, despite the persistent inhibition of ammonia excretion. Whole body ammonia and urea contents were not significantly altered by exposure to alkaline water. Protein and mRNA expression of Rhcg1, an apically expressed ammonia-conducting channel, were significantly elevated after 4-d exposure to alkaline water, whereas the mRNA expression of Rhag, Rhbg, and urea transporter were unaffected. The acute exposure to alkaline water of 4-dpf larvae reared in control water caused a rapid inhibition of ammonia excretion that had partially recovered within 6 h of continued exposure. The partial recovery of ammonia excretion despite continued exposure to alkaline water suggested an increased ammonia excretion capacity. In agreement with an increased capacity to excrete ammonia, the transfer of larvae back to the control (normal pH) water was accompanied by increased rates of ammonia excretion. Urea excretion was not stimulated during 6-h exposure to alkaline water. Following both chronic and acute exposure to alkaline water, the rate of uptake of methylamine (an ammonia analog) was significantly elevated, consistent with increased protein expression of the apical ammonia

  5. Targeted Mutagenesis of the Hypophysiotropic Gnrh3 in Zebrafish (Danio rerio Reveals No Effects on Reproductive Performance.

    Directory of Open Access Journals (Sweden)

    Olivia Smith Spicer

    Full Text Available Gnrh is the major neuropeptide regulator of vertebrate reproduction, triggering a cascade of events in the pituitary-gonadal axis that result in reproductive competence. Previous research in mice and humans has demonstrated that Gnrh/GNRH null mutations result in hypogonadotropic hypogonadism and infertility. The goal of this study was to eliminate gnrh3 (the hypophysiotropic Gnrh form function in zebrafish (Danio rerio to determine how ontogeny and reproductive performance are affected, as well as factors downstream of Gnrh3 along the reproductive axis. Using the TALEN technology, we developed a gnrh3-/- zebrafish line that harbors a 62 bp deletion in the gnrh3 gene. Our gnrh3-/- zebrafish line represents the first targeted and heritable mutation of a Gnrh isoform in any organism. Using immunohistochemistry, we verified that gnrh3-/- fish do not possess Gnrh3 peptide in any regions of the brain. However, other than changes in mRNA levels of pituitary gonadotropin genes (fshb, lhb, and cga during early development, which are corrected by adulthood, there were no changes in ontogeny and reproduction in gnrh3-/- fish. The gnrh3-/- zebrafish are fertile, displaying normal gametogenesis and reproductive performance in males and females. Together with our previous results that Gnrh3 cell ablation causes infertility, these results indicate that a compensatory mechanism is being activated, which is probably primed early on upon Gnrh3 neuron differentiation and possibly confined to Gnrh3 neurons. Potential compensation factors and sensitive windows of time for compensation during development and puberty should be explored.

  6. Embryonic exposure to carbendazim induces the transcription of genes related to apoptosis, immunotoxicity and endocrine disruption in zebrafish (Danio rerio).

    Science.gov (United States)

    Jiang, Jinhua; Wu, Shenggan; Wu, Changxing; An, Xuehua; Cai, Leiming; Zhao, Xueping

    2014-12-01

    Carbendazim is one of the most widespread environmental contaminant that can cause major concern to human and animal reproductive system. To date, very few studies have been conducted on the toxic effect of carbendazim in the non-target organism zebrafish (Danio rerio). The study presented here aimed to assess how carbendazim triggers apoptosis, immunotoxicity and endocrine disruption pathways in zebrafish during its embryo development. Our results demonstrated that the expression patterns of many key genes involved in cell apoptosis pathway (e.g. P53, Mdm2, Bbc3 and Cas8) were significantly up-regulated upon the exposure to carbendazim at the concentration of 500 μg/L, while the Bcl2 and Cas3 were down-regulated at the same concentration, interestingly, the expression level of Ogg1 decreased at all the exposure concentrations. It was also observed that the mRNA levels of CXCL-C1C, CCL1, IL-1b and TNFα which were closely related to the innate immune system, were affected in newly hatched zebrafish after exposed to different concentrations of carbendazim. Moreover, the expression of genes that are involved in the hypothalamic-pituitary-gonadal/thyroid (HPG/HPT) axis including VTG, ERα, ERβ2, Dio1, Dio2, Thraa and Thrb were all down-regulated significantly after the exposure to carbendazim. The expression levels of two cytochrome P450 aromatases CYP19a and CYP19b were increased significantly after 20 and 100 μg/L carbendazim exposure, respectively. Taken together, our results indicated that carbendazim had the potential to induce cell apoptosis and cause immune toxicity as well as endocrine disruption in zebrafish during the embryo developmental stage. The information presented here also help to elucidate the environmental risks caused by the carbendazim-induced toxicity in aquatic organisms. PMID:25304545

  7. Targeted Mutagenesis of the Hypophysiotropic Gnrh3 in Zebrafish (Danio rerio) Reveals No Effects on Reproductive Performance

    Science.gov (United States)

    Spicer, Olivia Smith; Wong, Ten-Tsao; Zmora, Nilli; Zohar, Yonathan

    2016-01-01

    Gnrh is the major neuropeptide regulator of vertebrate reproduction, triggering a cascade of events in the pituitary-gonadal axis that result in reproductive competence. Previous research in mice and humans has demonstrated that Gnrh/GNRH null mutations result in hypogonadotropic hypogonadism and infertility. The goal of this study was to eliminate gnrh3 (the hypophysiotropic Gnrh form) function in zebrafish (Danio rerio) to determine how ontogeny and reproductive performance are affected, as well as factors downstream of Gnrh3 along the reproductive axis. Using the TALEN technology, we developed a gnrh3-/- zebrafish line that harbors a 62 bp deletion in the gnrh3 gene. Our gnrh3-/- zebrafish line represents the first targeted and heritable mutation of a Gnrh isoform in any organism. Using immunohistochemistry, we verified that gnrh3-/- fish do not possess Gnrh3 peptide in any regions of the brain. However, other than changes in mRNA levels of pituitary gonadotropin genes (fshb, lhb, and cga) during early development, which are corrected by adulthood, there were no changes in ontogeny and reproduction in gnrh3-/- fish. The gnrh3-/- zebrafish are fertile, displaying normal gametogenesis and reproductive performance in males and females. Together with our previous results that Gnrh3 cell ablation causes infertility, these results indicate that a compensatory mechanism is being activated, which is probably primed early on upon Gnrh3 neuron differentiation and possibly confined to Gnrh3 neurons. Potential compensation factors and sensitive windows of time for compensation during development and puberty should be explored. PMID:27355207

  8. Antigen Uptake during Different Life Stages of Zebrafish (Danio rerio) Using a GFP-Tagged Yersinia ruckeri

    DEFF Research Database (Denmark)

    Korbut, Rozalia; Mehrdana, Foojan; Kania, Per Walter;

    2016-01-01

    Immersion-vaccines (bacterins) are routinely used for aquacultured rainbow trout to protect against Yersinia ruckeri (Yr). During immersion vaccination, rainbow trout take up and process the antigens, which induce protection. The zebrafish was used as a model organism to study uptake mechanisms...... and subsequent antigen transport in fish. A genetically modified Yr was developed to constitutively express green fluorescent protein (GFP) and was used for bacterin production. Larval, juvenile and adult transparent zebrafish (tra:nac mutant) received a bath in the bacterin for up to 30 minutes. Samples were...... was seen in the intestine 30 min pb and in the nares 2 hpb but never in scale pockets. Antigens were detected in the spleen 12 hpb. Zebrafish larvae exhibited major Yr uptake only in the mid-intestine enterocytes 24 hpb. The different life stages of zebrafish varied with regard to uptake locations, however...

  9. Antigen Uptake during Different Life Stages of Zebrafish (Danio rerio) Using a GFP-Tagged Yersinia ruckeri

    DEFF Research Database (Denmark)

    Korbut, Rozalia; Mehrdana, Foojan; Kania, Per Walter;

    2016-01-01

    and subsequent antigen transport in fish. A genetically modified Yr was developed to constitutively express green fluorescent protein (GFP) and was used for bacterin production. Larval, juvenile and adult transparent zebrafish (tra:nac mutant) received a bath in the bacterin for up to 30 minutes. Samples were......Immersion-vaccines (bacterins) are routinely used for aquacultured rainbow trout to protect against Yersinia ruckeri (Yr). During immersion vaccination, rainbow trout take up and process the antigens, which induce protection. The zebrafish was used as a model organism to study uptake mechanisms...... was seen in the intestine 30 min pb and in the nares 2 hpb but never in scale pockets. Antigens were detected in the spleen 12 hpb. Zebrafish larvae exhibited major Yr uptake only in the mid-intestine enterocytes 24 hpb. The different life stages of zebrafish varied with regard to uptake locations, however...

  10. Teratogenicity of Ochratoxin A and the Degradation Product, Ochratoxin α, in the Zebrafish (Danio rerio Embryo Model of Vertebrate Development

    Directory of Open Access Journals (Sweden)

    Mehreen Haq

    2016-02-01

    Full Text Available Ochratoxins, and particularly ochratoxin A (OTA, are toxic fungal-derived contaminants of food and other agricultural products. Growing evidence supports the degradation of OTA by chemical, enzymatic and/or microbial means as a potential approach to remove this mycotoxin from food products. In particular, hydrolysis of OTA to ochratoxin α (OTα and phenylalanine is the presumptive product of degradation in most cases. In the current study, we employed the zebrafish (Danio rerio embryo, as a model of vertebrate development to evaluate, the teratogenicity of OTA and OTα. These studies show that OTA is potently active in the zebrafish embryo toxicity assay (ZETA, and that toxicity is both concentration- and time-dependent with discernible and quantifiable developmental toxicity observed at nanomolar concentrations. On the other hand, OTα had no significant effect on embryo development at all concentrations tested supporting a decreased toxicity of this degradation product. Taken together, these results suggest that ZETA is a useful, and highly sensitive, tool for evaluating OTA toxicity, as well as its degradation products, toward development of effective detoxification strategies. Specifically, the results obtained with ZETA, in the present study, further demonstrate the toxicity of OTA, and support its degradation via hydrolysis to OTα as an effective means of detoxification.

  11. Teratogenicity of Ochratoxin A and the Degradation Product, Ochratoxin α, in the Zebrafish (Danio rerio) Embryo Model of Vertebrate Development

    Science.gov (United States)

    Haq, Mehreen; Gonzalez, Nelson; Mintz, Keenan; Jaja-Chimedza, Asha; De Jesus, Christopher Lawrence; Lydon, Christina; Welch, Aaron Z.; Berry, John P.

    2016-01-01

    Ochratoxins, and particularly ochratoxin A (OTA), are toxic fungal-derived contaminants of food and other agricultural products. Growing evidence supports the degradation of OTA by chemical, enzymatic and/or microbial means as a potential approach to remove this mycotoxin from food products. In particular, hydrolysis of OTA to ochratoxin α (OTα) and phenylalanine is the presumptive product of degradation in most cases. In the current study, we employed the zebrafish (Danio rerio) embryo, as a model of vertebrate development to evaluate, the teratogenicity of OTA and OTα. These studies show that OTA is potently active in the zebrafish embryo toxicity assay (ZETA), and that toxicity is both concentration- and time-dependent with discernible and quantifiable developmental toxicity observed at nanomolar concentrations. On the other hand, OTα had no significant effect on embryo development at all concentrations tested supporting a decreased toxicity of this degradation product. Taken together, these results suggest that ZETA is a useful, and highly sensitive, tool for evaluating OTA toxicity, as well as its degradation products, toward development of effective detoxification strategies. Specifically, the results obtained with ZETA, in the present study, further demonstrate the toxicity of OTA, and support its degradation via hydrolysis to OTα as an effective means of detoxification. PMID:26861395

  12. Bisphenol A causes reproductive toxicity, decreases dnmt1 transcription, and reduces global DNA methylation in breeding zebrafish (Danio rerio).

    Science.gov (United States)

    Laing, L V; Viana, J; Dempster, E L; Trznadel, M; Trunkfield, L A; Uren Webster, T M; van Aerle, R; Paull, G C; Wilson, R J; Mill, J; Santos, E M

    2016-07-01

    Bisphenol A (BPA) is a commercially important high production chemical widely used in epoxy resins and polycarbonate plastics, and is ubiquitous in the environment. Previous studies demonstrated that BPA activates estrogenic signaling pathways associated with adverse effects on reproduction in vertebrates and that exposure can induce epigenetic changes. We aimed to investigate the reproductive effects of BPA in a fish model and to document its mechanisms of toxicity. We exposed breeding groups of zebrafish (Danio rerio) to 0.01, 0.1, and 1 mg/L BPA for 15 d. We observed a significant increase in egg production, together with a reduced rate of fertilization in fish exposed to 1 mg/L BPA, associated with significant alterations in the transcription of genes involved in reproductive function and epigenetic processes in both liver and gonad tissue at concentrations representing hotspots of environmental contamination (0.1 mg/L) and above. Of note, we observed reduced expression of DNA methyltransferase 1 (dnmt1) at environmentally relevant concentrations of BPA, along with a significant reduction in global DNA methylation, in testes and ovaries following exposure to 1 mg/L BPA. Our findings demonstrate that BPA disrupts reproductive processes in zebrafish, likely via estrogenic mechanisms, and that environmentally relevant concentrations of BPA are associated with altered transcription of key enzymes involved in DNA methylation maintenance. These findings provide evidence of the mechanisms of action of BPA in a model vertebrate and advocate for its reduction in the environment. PMID:27120497

  13. Alterations along the Hypothalamic-Pituitary-Thyroid Axis of the Zebrafish (Danio rerio after Exposure to Propylthiouracil

    Directory of Open Access Journals (Sweden)

    Florian Schmidt

    2011-01-01

    Full Text Available In the past, various approaches have been developed to detect adverse effects of pollutants on the thyroid of vertebrates, most of these with special emphasis on the South African clawed frog, Xenopus laevis. Although fish are primarily affected by thyroid-disrupting chemicals, studies into alterations of the thyroid of fish are scarce. Therefore, effects of the reference compound propylthiouracil on histopathology of the thyroid axis were analyzed in a modified early life-stage test with zebrafish (Danio rerio exposed to propylthiouracil. The test substance induced dose-dependent alterations of thyroidal tissue concomitant with increases in the number of surrounding blood vessels. Despite this massive proliferation of the thyroid, zebrafish were not able to maintain thyroxin concentrations. The pituitary was affected displaying significant alterations in thyroid-stimulating hormone cell counts. Quantitative evaluation of pituitary surface areas revealed a dose-dependent increase of adenohypophyseal tissue. Distinct histopathological effects may contribute to a more easy identification and interpretation of alterations induced by thyroid-disrupting chemicals.

  14. The zebrafish (Danio rerio) embryo as a model system for identification and characterization of developmental toxins from marine and freshwater microalgae☆

    OpenAIRE

    Berry, John P.; Gantar, Miroslav; Patrick D. L. Gibbs; Schmale, Michael C.

    2006-01-01

    The zebrafish (Danio rerio) embryo has emerged as an important model of vertebrate development. As such, this model system is finding utility in the investigation of toxic agents that inhibit, or otherwise interfere with, developmental processes (i.e. developmental toxins), including compounds that have potential relevance to both human and environmental health, as well as biomedicine. Recently, this system has been applied increasingly to the study of microbial toxins, and more specifically,...

  15. Hypoxia-induced retinopathy model in adult zebrafish

    DEFF Research Database (Denmark)

    Cao, Ziquan; Jensen, Lasse D.; Rouhi, Pegah;

    2010-01-01

    . In this article, we describe protocols that create hypoxia-induced retinopathy in adult zebrafish. Adult fli1: EGFP zebrafish are placed in hypoxic water for 3-10 d and retinal neovascularization is analyzed using confocal microscopy. It usually takes 11 d to obtain conclusive results using the hypoxia...

  16. Genome-wide identification of suitable zebrafish Danio rerio reference genes for normalization of gene expression data by RT-qPCR.

    Science.gov (United States)

    Xu, H; Li, C; Zeng, Q; Agrawal, I; Zhu, X; Gong, Z

    2016-06-01

    In this study, to systematically identify the most stably expressed genes for internal reference in zebrafish Danio rerio investigations, 37 D. rerio transcriptomic datasets (both RNA sequencing and microarray data) were collected from gene expression omnibus (GEO) database and unpublished data, and gene expression variations were analysed under three experimental conditions: tissue types, developmental stages and chemical treatments. Forty-four putative candidate genes were identified with the c.v. housekeeping genes (eef1a1l1, b2m, hrpt1l and actb1), were selected from different functional groups for further quantitative real-time (qrt-)PCR validation using 25 RNA samples from different adult tissues, developmental stages and chemical treatments. The qrt-PCR data were then analysed using the statistical algorithm refFinder for gene expression stability. Several new candidate genes showed better expression stability than the conventional housekeeping genes in all three categories. It was found that sep15 and metap1 were the top two stable genes for tissue types, ube2a and tmem50a the top two for different developmental stages, and rpl13a and rp1p0 the top two for chemical treatments. Thus, based on the extensive transcriptomic analyses and qrt-PCR validation, these new reference genes are recommended for normalization of D. rerio qrt-PCR data respectively for the three different experimental conditions. PMID:27126589

  17. Hypoxia impairs primordial germ cell migration in zebrafish (Danio rerio embryos.

    Directory of Open Access Journals (Sweden)

    Kwok Hong Lo

    Full Text Available BACKGROUND: As a global environmental concern, hypoxia is known to be associated with many biological and physiological impairments in aquatic ecosystems. Previous studies have mainly focused on the effect of hypoxia in adult animals. However, the effect of hypoxia and the underlying mechanism of how hypoxia affects embryonic development of aquatic animals remain unclear. METHODOLOGY/PRINCIPAL FINDINGS: In the current study, the effect of hypoxia on primordial germ cell (PGC migration in zebrafish embryos was investigated. Hypoxic embryos showed PGC migration defect as indicated by the presence of mis-migrated ectopic PGCs. Insulin-like growth factor (IGF signaling is required for embryonic germ line development. Using real-time PCR, we found that the mRNA expression levels of insulin-like growth factor binding protein (IGFBP-1, an inhibitor of IGF bioactivity, were significantly increased in hypoxic embryos. Morpholino knockdown of IGFBP-1 rescued the PGC migration defect phenotype in hypoxic embryos, suggesting the role of IGFBP-1 in inducing PGC mis-migration. CONCLUSIONS/SIGNIFICANCE: This study provides novel evidence that hypoxia disrupts PGC migration during embryonic development in fish. IGF signaling is shown to be one of the possible mechanisms for the causal link between hypoxia and PGC migration. We propose that hypoxia causes PGC migration defect by inhibiting IGF signaling through the induction of IGFBP-1.

  18. Effects of tris(2-butoxyethyl) phosphate exposure on endocrine systems and reproduction of zebrafish (Danio rerio).

    Science.gov (United States)

    Kwon, Bareum; Shin, Hyejin; Moon, Hyo-Bang; Ji, Kyunghee; Kim, Ki-Tae

    2016-07-01

    Tris(2-butoxyethyl) phosphate (TBEOP), a widely used organophosphate flame retardant, has frequently been detected both in the environment and the biota. However, limited information is available on the effects of TBEOP on the endocrine system and its underlying mechanisms. We exposed adult zebrafish pairs to TBEOP at concentrations of 0, 2.1, 11, and 118 μg/L for 21 d, and investigated the effects on gene transcription and hormone production related to the hypothalamic-pituitary-gonadal (HPG) axis, and on reproduction. The adverse effects on the F1 generation were further examined. In male fish, plasma concentrations of 17β-estradiol were significantly increased along with up-regulation of cyp19a. Exposure to TBEOP at 118 μg/L led to a significant decrease in average egg production. Exposure of the F0 generation to TBEOP delayed hatching and lowered hatching rates in the F1 generation. The results demonstrate that exposure to TBEOP at environmentally relevant concentration levels could affect the sex hormone balance by altering regulatory circuits of the HPG axis, eventually leading to disruption of reproductive performance and the development of offspring. PMID:27131816

  19. Zebrafish (Danio rerio) behavioural response to bioinspired robotic fish and mosquitofish (Gambusia affinis).

    Science.gov (United States)

    Polverino, Giovanni; Porfiri, Maurizio

    2013-12-01

    The field of ethorobotics holds promise in aiding fundamental research in animal behaviour, whereby it affords fully controllable and easily reproducible experimental tools. Most of the current ethorobotics studies are focused on the behavioural response of a selected target species as it interacts with a biologically-inspired robot in controlled laboratory conditions. In this work, we first explore the interactions between two social fish species and a robotic fish, whose design is inspired by salient visual features of one of the species. Specifically, this study investigates the behavioural response of small shoals of zebrafish interacting with a zebrafish-inspired robotic fish and small shoals of mosquitofish in a basic ecological context. Our results demonstrate that the robotic fish differentially influences the behaviour of the two species by consistently attracting zebrafish, while repelling mosquitofish. This selective behavioural control is successful in spatially isolating the two species, which would otherwise exhibit prey-predator interactions, with mosquitofish attacking zebrafish. PMID:23999758

  20. Sodium and chloride transport in soft water and hard water acclimated zebrafish (Danio rerio)

    DEFF Research Database (Denmark)

    Boisen, A M Z; Amstrup, J; Novak, I;

    2003-01-01

    While the zebrafish is commonly used for studies of developmental biology and toxicology, very little is known about their osmoregulatory physiology. The present investigation of Na(+) and Cl(-) transport revealed that the zebrafish is able to tolerate extremely low ambient ion concentrations...... and that this is achieved at least in part by a greatly enhanced apparent uptake capacity and affinity for both ions. Zebrafish maintain plasma and whole body electrolyte concentrations similar to most other freshwater teleosts even in deionized water containing only 35 microM NaCl, i.e soft water. We recorded an extremely...... inhibitor was more variable. Differential response of Na(+) uptake to amiloride depending on acclimation medium suggests that different Na(+) transport mechanisms are employed by zebrafish acclimated to soft and hard water....

  1. Efficient expression of transgenes in adult zebrafish by electroporation

    Directory of Open Access Journals (Sweden)

    Rao S Hari

    2005-10-01

    Full Text Available Abstract Background Expression of transgenes in muscle by injection of naked DNA is widely practiced. Application of electrical pulses at the site of injection was demonstrated to improve transgene expression in muscle tissue. Zebrafish is a precious model to investigate developmental biology in vertebrates. In this study we investigated the effect of electroporation on expression of transgenes in 3–6 month old adult zebrafish. Results Electroporation parameters such as number of pulses, voltage and amount of plasmid DNA were optimized and it was found that 6 pulses of 40 V·cm-1 at 15 μg of plasmid DNA per fish increased the luciferase expression 10-fold compared to controls. Similar enhancement in transgene expression was also observed in Indian carp (Labeo rohita. To establish the utility of adult zebrafish as a system for transient transfections, the strength of the promoters was compared in A2 cells and adult zebrafish after electroporation. The relative strengths of the promoters were found to be similar in cell lines and in adult zebrafish. GFP fluorescence in tissues after electroporation was also studied by fluorescence microscopy. Conclusion Electroporation after DNA injection enhances gene expression 10-fold in adult zebrafish. Electroporation parameters for optimum transfection of adult zebrafish with tweezer type electrode were presented. Enhanced reporter gene expression upon electroporation allowed comparison of strengths of the promoters in vivo in zebrafish.

  2. Halogenated bisphenol-A analogs act as obesogens in zebrafish larvae (Danio rerio).

    Science.gov (United States)

    Riu, Anne; McCollum, Catherine W; Pinto, Caroline L; Grimaldi, Marina; Hillenweck, Anne; Perdu, Elisabeth; Zalko, Daniel; Bernard, Laure; Laudet, Vincent; Balaguer, Patrick; Bondesson, Maria; Gustafsson, Jan-Ake

    2014-05-01

    Obesity has increased dramatically over the past decades, reaching epidemic proportions. The reasons are likely multifactorial. One of the suggested causes is the accelerated exposure to obesity-inducing chemicals (obesogens). However, out of the tens of thousands of industrial chemicals humans are exposed to, very few have been tested for their obesogenic potential, mostly due to the limited availability of appropriate in vivo screening models. In this study, we investigated whether two commonly used flame retardants, the halogenated bisphenol-A (BPA) analogs tetrabromobisphenol-A (TBBPA) and tetrachlorobisphenol-A (TCBPA), could act as obesogens using zebrafish larvae as an in vivo animal model. The effect of embryonic exposure to these chemicals on lipid accumulation was analyzed by Oil Red-O staining, and correlated to their capacity to activate human and zebrafish peroxisome proliferator-activated receptor gamma (PPARγ) in zebrafish and in reporter cell lines. Then, the metabolic fate of TBBPA and TCBPA in zebrafish larvae was analyzed by high-performance liquid chromatography (HPLC) . TBBPA and TCBPA were readily taken up by the fish embryo and both compounds were biotransformed to sulfate-conjugated metabolites. Both halogenated-BPAs, as well as TBBPA-sulfate induced lipid accumulation in zebrafish larvae. TBBPA and TCBPA also induced late-onset weight gain in juvenile zebrafish. These effects correlated to their capacity to act as zebrafish PPARγ agonists. Screening of chemicals for inherent obesogenic capacities through the zebrafish lipid accumulation model could facilitate prioritizing chemicals for further investigations in rodents, and ultimately, help protect humans from exposure to environmental obesogens. PMID:24591153

  3. Validation of Zebrafish (Danio rerio) Reference Genes for Quantitative Real-time RT-PCR Normalization

    Institute of Scientific and Technical Information of China (English)

    Rongying TANG; Andrew DODD; Daniel LAI; Warren C.MCNABB; Donald R.LOVE

    2007-01-01

    The normalization of quantitative real time RT-PCR (qRT-PCR) is important to obtain accurate gene expression data. The most common method for qRT-PCR normalization is to use reference, or housekeeping genes. However, there is emerging evidence that even reference genes can be regulated under different conditions, qRT-PCR has only recently been used in terms of zebrafish gene expression studies and there is no validated set of reference genes. This study characterizes the expression of nine possible reference genes during zebrafish embryonic development and in a zebrafish tissue panel. All nine reference genes exhibited variable expression. The β-actin, EF1α and Rpl13α genes comprise a validated reference gene panel for zebrafish developmental time course studies, and the EF1α, Rpl13α and 18S rRNA genes are more suitable as a reference gene panel for zebrafish tissue analysis. Importantly, the zebrafish GAPDH gene appears unsuitable as reference gene for both types of studies.

  4. Antigen Uptake during Different Life Stages of Zebrafish (Danio rerio) Using a GFP-Tagged Yersinia ruckeri.

    Science.gov (United States)

    Korbut, Rozalia; Mehrdana, Foojan; Kania, Per Walter; Larsen, Marianne Halberg; Frees, Dorte; Dalsgaard, Inger; Jørgensen, Louise von Gersdorff

    2016-01-01

    Immersion-vaccines (bacterins) are routinely used for aquacultured rainbow trout to protect against Yersinia ruckeri (Yr). During immersion vaccination, rainbow trout take up and process the antigens, which induce protection. The zebrafish was used as a model organism to study uptake mechanisms and subsequent antigen transport in fish. A genetically modified Yr was developed to constitutively express green fluorescent protein (GFP) and was used for bacterin production. Larval, juvenile and adult transparent zebrafish (tra:nac mutant) received a bath in the bacterin for up to 30 minutes. Samples were taken after 1 min, 15 min, 30 min, 2 h, 12 h and 24 h. At each sampling point fish were used for live imaging of the uptake using a fluorescence stereomicroscope and for immunohistochemistry (IHC). In adult fish, the bacterin could be traced within 30 min in scale pockets, skin, oesophagus, intestine and fins. Within two hours post bath (pb) Yr-antigens were visible in the spleen and at 24 h in liver and kidney. Bacteria were associated with the gills, but uptake at this location was limited. Antigens were rarely detected in the blood and never in the nares. In juvenile fish uptake of the bacterin was seen in the intestine 30 min pb and in the nares 2 hpb but never in scale pockets. Antigens were detected in the spleen 12 hpb. Zebrafish larvae exhibited major Yr uptake only in the mid-intestine enterocytes 24 hpb. The different life stages of zebrafish varied with regard to uptake locations, however the gut was consistently a major uptake site. Zebrafish and rainbow trout tend to have similar uptake mechanisms following immersion or bath vaccination, which points towards zebrafish as a suitable model organism for this aquacultured species. PMID:27404564

  5. Protective Yeasts Control V. anguillarum Pathogenicity and Modulate the Innate Immune Response of Challenged Zebrafish (Danio rerio) Larvae

    Science.gov (United States)

    Caruffo, Mario; Navarrete, Natalie C.; Salgado, Oscar A.; Faúndez, Nelly B.; Gajardo, Miguel C.; Feijóo, Carmen G.; Reyes-Jara, Angélica; García, Katherine; Navarrete, Paola

    2016-01-01

    We investigated mechanisms involved in the protection of zebrafish (Danio rerio) larvae by two probiotic candidate yeasts, Debaryomyces hansenii 97 (Dh97) and Yarrowia lypolitica 242 (Yl242), against a Vibrio anguillarum challenge. We determined the effect of different yeast concentrations (104–107 CFU/mL) to: (i) protect larvae from the challenge, (ii) reduce the in vivo pathogen concentration and (iii) modulate the innate immune response of the host. To evaluate the role of zebrafish microbiota in protection, the experiments were performed in conventionally raised and germ-free larvae. In vitro co-aggregation assays were performed to determine a direct yeast-pathogen interaction. Results showed that both yeasts significantly increased the survival rate of conventionally raised larvae challenged with V. anguillarum. The concentration of yeasts in larvae tended to increase with yeast inoculum, which was more pronounced for Dh97. Better protection was observed with Dh97 at a concentration of 106 CFU/mL compared to 104 CFU/mL. In germ-free conditions V. anguillarum reached higher concentrations in larvae and provoked significantly more mortality than in conventional conditions, revealing the protective role of the host microbiota. Interestingly, yeasts were equally (Dh97) or more effective (Yl242) in protecting germ-free than conventionally-raised larvae, showing that protection can be exerted only by yeasts and is not necessarily related to modulation of the host microbiota. Although none of the yeasts co-aggregated with V. anguillarum, they were able to reduce its proliferation in conventionally raised larvae, reduce initial pathogen concentration in germ-free larvae and prevent the upregulation of key components of the inflammatory/anti-inflammatory response (il1b, tnfa, c3, mpx, and il10, respectively). These results show that protection by yeasts of zebrafish larvae challenged with V. anguillarum relates to an in vivo anti-pathogen effect, the modulation of

  6. Structural and functional characterization of neuromedin S in the teleost fish, zebrafish (Danio rerio).

    Science.gov (United States)

    Chen, Huapu; Huang, Hongxin; Chen, Xinggui; Deng, Siping; Zhu, Chunhua; Huang, Hai; Li, Guangli

    2016-01-01

    Neuromedin S (NMS) has been demonstrated to have important roles in many vertebrate physiological processes. However, the function of NMS in teleost fishes remains unclear. We explored the physiological roles of the NMS gene in the zebrafish model. An NMS cDNA was cloned from zebrafish brain tissue, and the full-length cDNA sequence was 521 bp in length and encoded a precursor of 110 amino acid residues. Interestingly, fish prepro-NMS is predicted to generate a short 34-residue peptide, designated as NMS-related peptide (NMSRP). Zebrafish prepro-NMS does not contain the NMS peptide which is found in the NMS precursors of mammals, and just retains the MNSRP peptide. A multiple-species sequence alignment showed that NMSRPs are conserved among the other sampled vertebrates. Zebrafish NMS mRNA was detected by RT-PCR revealing a tissue-specific distribution with high levels of expression in the brain, spleen, ovary, pituitary, and muscle. Furthermore, the locations of NMS-expressing cells in the zebrafish brain were detected by in situ hybridization in the parvocellular preoptic nucleus (PPa), the ventral zone of the periventricular hypothalamus (Hv), and lateral hypothalamic nucleus (LH). The levels of NMS mRNA in the hypothalamus were significantly increased after three days of food deprivation. Administration of zebrafish NMSRP by intraperitoneal injection significantly promoted the expression of neuropeptide Y (NPY) and orexin, suggesting an orexigenic role for NMSRP in zebrafish. The present study offers a new understanding of the NMS gene in vertebrates and increases our knowledge of the neuroendocrine regulation of feeding.

  7. Centrosomes in the zebrafish (Danio rerio: a review including the related basal body

    Directory of Open Access Journals (Sweden)

    Lessman Charles A

    2012-06-01

    Full Text Available Abstract Ever since Edouard Van Beneden and Theodor Boveri first formally described the centrosome in the late 1800s, it has captivated cell biologists. The name clearly indicated its central importance to cell functioning, even to these early investigators. We now know of its role as a major microtubule-organizing center (MTOC and of its dynamic roles in cell division, vesicle trafficking and for its relative, the basal body, ciliogenesis. While centrosomes are found in most animal cells, notably it is absent in most oocytes and higher plant cells. Nevertheless, it appears that critical components of the centrosome act as MTOCs in these cells as well. The zebrafish has emerged as an exciting and promising new model organism, primarily due to the pioneering efforts of George Streisinger to use zebrafish in genetic studies and due to Christiane Nusslein-Volhard, Wolfgang Driever and their teams of collaborators, who applied forward genetics to elicit a large number of mutant lines. The transparency and rapid external development of the embryo allow for experiments not easily done in other vertebrates. The ease of producing transgenic lines, often with the use of fluorescent reporters, and gene knockdowns with antisense morpholinos further contributes to the appeal of the model as an experimental system. The added advantage of high-throughput screening of small-molecule libraries, as well as the ease of mass rearing together with low cost, makes the zebrafish a true frontrunner as a model vertebrate organism. The zebrafish has a body plan shared by all vertebrates, including humans. This conservation of body plan provides added significance to the existing lines of zebrafish as human disease models and adds an impetus to the ongoing efforts to develop new models. In this review, the current state of knowledge about the centrosome in the zebrafish model is explored. Also, studies on the related basal body in zebrafish and their relationship to

  8. Structural and functional characterization of neuromedin S in the teleost fish, zebrafish (Danio rerio).

    Science.gov (United States)

    Chen, Huapu; Huang, Hongxin; Chen, Xinggui; Deng, Siping; Zhu, Chunhua; Huang, Hai; Li, Guangli

    2016-01-01

    Neuromedin S (NMS) has been demonstrated to have important roles in many vertebrate physiological processes. However, the function of NMS in teleost fishes remains unclear. We explored the physiological roles of the NMS gene in the zebrafish model. An NMS cDNA was cloned from zebrafish brain tissue, and the full-length cDNA sequence was 521 bp in length and encoded a precursor of 110 amino acid residues. Interestingly, fish prepro-NMS is predicted to generate a short 34-residue peptide, designated as NMS-related peptide (NMSRP). Zebrafish prepro-NMS does not contain the NMS peptide which is found in the NMS precursors of mammals, and just retains the MNSRP peptide. A multiple-species sequence alignment showed that NMSRPs are conserved among the other sampled vertebrates. Zebrafish NMS mRNA was detected by RT-PCR revealing a tissue-specific distribution with high levels of expression in the brain, spleen, ovary, pituitary, and muscle. Furthermore, the locations of NMS-expressing cells in the zebrafish brain were detected by in situ hybridization in the parvocellular preoptic nucleus (PPa), the ventral zone of the periventricular hypothalamus (Hv), and lateral hypothalamic nucleus (LH). The levels of NMS mRNA in the hypothalamus were significantly increased after three days of food deprivation. Administration of zebrafish NMSRP by intraperitoneal injection significantly promoted the expression of neuropeptide Y (NPY) and orexin, suggesting an orexigenic role for NMSRP in zebrafish. The present study offers a new understanding of the NMS gene in vertebrates and increases our knowledge of the neuroendocrine regulation of feeding. PMID:26415865

  9. Tolerance and efficacy of emamectin benzoate and ivermectin for the treatment of Pseudocapillaria tomentosa in laboratory zebrafish (Danio rerio).

    Science.gov (United States)

    Collymore, Chereen; Watral, Virginia; White, Julie R; Colvin, Michael E; Rasmussen, Skye; Tolwani, Ravi J; Kent, Michael L

    2014-10-01

    Tolerance of adult zebrafish and efficacy of emamectin benzoate and ivermectin in eliminating Pseudocapillaria tomentosa infection were evaluated. In the tolerance study, behavioral changes, fecundity, histopathology, and mortality were evaluated for in-feed administration of emamectin (0.05, 0.10, and 0.25 mg/kg) and ivermectin (0.05 and 0.10 mg/kg). All doses of emamectin were well tolerated. Ivermectin 0.05 mg/kg administration resulted in mild behavioral changes and a transient decrease in fecundity. Ivermectin 0.10 mg/kg administration resulted in severe behavioral changes and some mortality. In the efficacy study, emamectin (0.05 and 0.25 mg/kg) and ivermectin (0.05 mg/kg) were evaluated for their efficacy in eliminating P. tomentosa infection. Emamectin reduced parasite burden in infected zebrafish, and ivermectin eliminated intestinal nematode infections. Despite a small margin of safety, ivermectin 0.05 mg/kg was effective at eliminating P. tomentosa infection in adult zebrafish. Higher doses or a longer course of treatment may be needed for complete elimination of P. tomentosa infection using emamectin. In this study, we propose two possible treatments for intestinal nematode infections in zebrafish.

  10. Impact of endocrine-disrupting chemicals on reproductive function in zebrafish (Danio rerio).

    Science.gov (United States)

    Huang, Y; Wang, X L; Zhang, J W; Wu, K S

    2015-02-01

    The prevalence of endocrine-disrupting chemicals (EDCs) in the aquatic environment has been associated with the wide detection of alterations in the development and physiology of vertebrates. Zebrafish, as a model species, has been extensively used in toxicological research. In this review, we focus on recent published evidence of the harmful effects of EDCs on reproductive function in zebrafish, including skewed sex ratio, immature gonads, diminished sexual behaviour, decreased sperm count, reduced spawning and fertilization. These impairments mostly result from disruption to sex-steroid hormones induced by endocrine disruptors. We also discuss other effects of exposure to EDCs. In EDC exposure research, despite incomplete assessments of altered gonad histopathology and sexual behaviour, these present potential effective biomarkers or pathways for evaluating the reproductive function in zebrafish on EDC exposure. To date, the pernicious effects of some EDCs on the reproductive performance in laboratory zebrafish are well understood; however, similar alterations remain for further determination in wild-type fish and more kinds of EDCs. More studies should be performed under established scientific regulatory criteria to investigate the impact of EDCs on reproduction in zebrafish. Moreover, further research is required to explain the definite mechanism of sexual differentiation, which helps in understanding the shift of sexual phenotype with EDC exposure. PMID:25529055

  11. Evaluation of carbon nanotubes network toxicity in zebrafish (Danio rerio) model.

    Science.gov (United States)

    Filho, Jose de Souza; Matsubara, Elaine Y; Franchi, Leonardo Pereira; Martins, Igor Pinheiro; Rivera, Luis Miguel Ramires; Rosolen, José Mauricio; Grisolia, Cesar Koppe

    2014-10-01

    This is a detailed in vivo study of the biological response to carbon nanotubes network as probed by the zebrafish model. First, we prepared pristine carbon nanotubes (CNTs) by methanol chemical vapor deposition in the presence of Mn and Co as catalysts, followed by purification in acid, which furnished curved tubes with diameters lying between 10 and 130 nm. The CNT network consisted of pristine CNTs dispersed in water in the presence of a surfactant. The CNT network pellets corresponded to agglomerated multi-walled CNTs with an average diameter of about 500 nm. Although the same pristine CNTs had been previously found to exert genotoxic effects in vitro, here we verified that the CNT network was not genotoxic in vivo. Indeed, Raman spectroscopy and microscopy conducted in the intestine of the zebrafish revealed complete clearance of the CNT network as well as minimal disturbances, such as aneurysms, hyperemia, and reversible inflammatory focus in the zebrafish gills.

  12. The effects of waterborne uranium on the hatching success, development, and survival of early life stages of zebrafish (Danio rerio)

    Energy Technology Data Exchange (ETDEWEB)

    Bourrachot, Stephanie [Laboratoire de Radioecologie et Ecotoxicologie, IRSN, Cadarache, 13115 Saint-Paul-lez-Durance (France)], E-mail: stephanie.bourrachot@irsn.fr; Simon, Olivier; Gilbin, Rodolphe [Laboratoire de Radioecologie et Ecotoxicologie, IRSN, Cadarache, 13115 Saint-Paul-lez-Durance (France)

    2008-10-20

    In this study, we investigated the effects of the radioactive metal uranium (U) on the embryonic development, hatching success, growth rate, and survival of juvenile zebrafish (Danio rerio). We studied the effects of depleted uranium (20-500 {mu}g L{sup -1} of DU), inducing mainly chemical toxicity due to its low specific activity, and the combined effects of chemical and radiological toxicity by using a higher specific activity uranium isotope (20 and 100 {mu}g L{sup -1} of {sup 233}U). Results showed that early life stages are significantly affected by uranium exposure through both chemical and combined (chemical and radiological) toxicity. Experiments showed significant effects of U on hatching success starting at the concentration of 250 {mu}g L{sup -1} of DU, causing a 42% delay in median hatching times relative to control. Furthermore, a reduction of growth (decrease in body length and weight) was observed followed by a high mortality of pro-larvae stage (up to 100% at DU concentrations of 250 {mu}g L{sup -1} upon a 15 day exposure). Bioaccumulation measurements highlighted that U was mainly localised in the chorion but penetrated in the embryo inside eggs at a higher concentration. The effects differed depending on the isotopic composition of the uranium: sublethal defects in the tail detachment process were more pronounced for {sup 233}U than DU exposure, while the presence of {sup 233}U specifically affected embryo development and led to higher mortality rates of the prolarvae. The results from this study showed that the early life stages of zebrafish seems to be more sensitive to uranium contamination than more mature stages, and underline the importance of including pro-larval stages into toxicity tests in order to improve the relevancy for environmental risk assessments.

  13. Biodistribution and toxicological study of PEGylated single-wall carbon nanotubes in the zebrafish (Danio rerio) nervous system

    Energy Technology Data Exchange (ETDEWEB)

    Weber, Gisele E.B.; Dal Bosco, Lidiane [Laboratório de Neurociências, Instituto de Ciências Biológicas, Universidade Federal do Rio Grande (FURG), Rio Grande, RS, 96210-900 (Brazil); Programa de Pós-graduação em Ciências Fisiológicas–Fisiologia Animal Comparada, FURG, Rio Grande, RS, 96210-900 (Brazil); Gonçalves, Carla O.F.; Santos, Adelina P. [Laboratório de Química de Nanoestruturas, Centro de Desenvolvimento da Tecnologia Nuclear, Belo Horizonte, MG, 31270-901 (Brazil); Fantini, Cristiano [Instituto de Ciências Exatas, Departamento de Física, Belo Horizonte, MG, 31270-901 (Brazil); Furtado, Clascídia A. [Laboratório de Química de Nanoestruturas, Centro de Desenvolvimento da Tecnologia Nuclear, Belo Horizonte, MG, 31270-901 (Brazil); Parfitt, Gustavo M.; Peixoto, Carolina [Laboratório de Neurociências, Instituto de Ciências Biológicas, Universidade Federal do Rio Grande (FURG), Rio Grande, RS, 96210-900 (Brazil); Programa de Pós-graduação em Ciências Fisiológicas–Fisiologia Animal Comparada, FURG, Rio Grande, RS, 96210-900 (Brazil); Romano, Luis Alberto [Instituto de Oceanografía, Universidade Federal do Rio Grande, Rio Grande, RS, 96210-030 (Brazil); and others

    2014-11-01

    Nanotechnology has been proven to be increasingly compatible with pharmacological and biomedical applications. Therefore, we evaluated the biological interactions of single-wall carbon nanotubes functionalized with polyethylene glycol (SWNT-PEG). For this purpose, we analyzed biochemical, histological, behavioral and biodistribution parameters to understand how this material behaves in vitro and in vivo using the fish Danio rerio (zebrafish) as a biological model. The in vitro results for fish brain homogenates indicated that SWNT-PEG had an effect on lipid peroxidation and GSH (reduced glutathione) content. However, after intraperitoneal exposure, SWNT-PEG proved to be less biocompatible and formed aggregates, suggesting that the PEG used for the nanoparticle functionalization was of an inappropriate size for maintaining product stability in a biological environment. This problem with functionalization may have contributed to the low or practically absent biodistribution of SWNT-PEG in zebrafish tissues, as verified by Raman spectroscopy. There was an accumulation of material in the abdominal cavity that led to inflammation and behavioral disturbances, as evaluated by a histological analysis and an open field test, respectively. These results provide evidence of a lack of biocompatibility of SWNTs modified with short chain PEGs, which leads to the accumulation of the material, tissue damage and behavioral alterations in the tested subjects. - Highlights: • In vitro brain exposure diminished lipid peroxidation. • In vitro brain exposure depletes the GSH content. • SWNT-PEG was not biocompatible and formed aggregates after the exposure. • Practically absent biodistribution of SWNT-PEG was observed by Raman spectroscopy. • SWNT-PEG exposure lead to tissue damage and inflammatory responses.

  14. Effects of depleted uranium on the reproductive success and F1 generation survival of zebrafish (Danio rerio).

    Science.gov (United States)

    Bourrachot, Stéphanie; Brion, François; Pereira, Sandrine; Floriani, Magali; Camilleri, Virginie; Cavalié, Isabelle; Palluel, Olivier; Adam-Guillermin, Christelle

    2014-09-01

    Despite the well-characterized occurrence of uranium (U) in the aquatic environment, very little is known about the chronic exposure of fish to low levels of U and its potential effect on reproduction. Therefore, this study was undertaken to investigate the effects of environmental concentrations of depleted U on the reproductive output of zebrafish (Danio rerio) and on survival and development of the F1 embryo-larvae following parental exposure to U. For that purpose, sexually mature male and female zebrafish were exposed to 20 and 250 μg/L of U for 14 days and allowed to reproduce in clean water during a further 14-day period. At all sampling times, whole-body vitellogenin concentrations and gonad histology were analyzed to investigate the effects of U exposure on these reproductive endpoints. In addition, accumulation of U in the gonads and its genotoxic effect on male and female gonad cells were quantified. The results showed that U strongly affected the capability of fish to reproduce and to generate viable individuals as evidenced by the inhibition of egg production and the increased rate of mortality of the F1 embryos. Interestingly, U exposure resulted in decreased circulating concentrations of vitellogenin in females. Increased concentrations of U were observed in gonads and eggs, which were most likely responsible for the genotoxic effects seen in fish gonads and in embryos exposed maternally to U. Altogether, these findings highlight the negative effect of environmentally relevant concentrations of U which alter the reproductive capability of fish and impair the genetic integrity of F1 embryos raising further concern regarding its effect at the population level. PMID:24846854

  15. Biodistribution and toxicological study of PEGylated single-wall carbon nanotubes in the zebrafish (Danio rerio) nervous system

    International Nuclear Information System (INIS)

    Nanotechnology has been proven to be increasingly compatible with pharmacological and biomedical applications. Therefore, we evaluated the biological interactions of single-wall carbon nanotubes functionalized with polyethylene glycol (SWNT-PEG). For this purpose, we analyzed biochemical, histological, behavioral and biodistribution parameters to understand how this material behaves in vitro and in vivo using the fish Danio rerio (zebrafish) as a biological model. The in vitro results for fish brain homogenates indicated that SWNT-PEG had an effect on lipid peroxidation and GSH (reduced glutathione) content. However, after intraperitoneal exposure, SWNT-PEG proved to be less biocompatible and formed aggregates, suggesting that the PEG used for the nanoparticle functionalization was of an inappropriate size for maintaining product stability in a biological environment. This problem with functionalization may have contributed to the low or practically absent biodistribution of SWNT-PEG in zebrafish tissues, as verified by Raman spectroscopy. There was an accumulation of material in the abdominal cavity that led to inflammation and behavioral disturbances, as evaluated by a histological analysis and an open field test, respectively. These results provide evidence of a lack of biocompatibility of SWNTs modified with short chain PEGs, which leads to the accumulation of the material, tissue damage and behavioral alterations in the tested subjects. - Highlights: • In vitro brain exposure diminished lipid peroxidation. • In vitro brain exposure depletes the GSH content. • SWNT-PEG was not biocompatible and formed aggregates after the exposure. • Practically absent biodistribution of SWNT-PEG was observed by Raman spectroscopy. • SWNT-PEG exposure lead to tissue damage and inflammatory responses

  16. The effects of dietary iron concentration on gastrointestinal and branchial assimilation of both iron and cadmium in zebrafish (Danio rerio)

    International Nuclear Information System (INIS)

    Zebrafish (Danio rerio) were fed either a diet containing 33 mg Fe kg-1 (low) or 95 mg Fe kg-1 (normal) for 10 weeks, after which short-term Cd and Fe uptake by the gastrointestinal tract and gill was assessed. Carcass metal content and transcript levels of the iron importer, Divalent Metal Transporter 1 (DMT1) and an iron exporter, ferroportin1, in both the gastrointestinal tract and gill were also measured. Fish fed the low Fe diet accumulated 13 times more Cd into their livers via the gastrointestinal tract than those fed the normal Fe diet. However, no significant increase in liver Fe accumulation was measured. Concomitantly, when exposed to 48 nmol Cd L-1 fish fed the low Fe diet exhibited a ∼4-fold increase in Cd accumulation on the gill and in the liver, compared to those fed a normal diet. In addition, fish fed the low Fe diet also significantly accumulated more Fe on the gill (nine-fold increase) and into the carcass (four-fold increase) when exposed to 96 nmol Fe L-1, compared to fish fed a normal diet. Surprisingly, carcass Fe, Ca and Mg concentrations were increased in fish fed the low Fe diet, which suggests that Fe body levels may not be a good indicator of whether a fish is more or less susceptible to increased non-essential metal accumulation via an Fe uptake pathway. However, significantly elevated transcript levels of DMT1 and ferroportin1 (2.7- and 3.8-fold induction, respectively) were seen in the gastrointestinal tract, and DMT1 in the gills (1.8-fold induction) of zebrafish fed a low Fe diet. The correlation between Cd uptake and DMT1 expression suggests that one route of uptake of Cd, either from the diet or from the water, could be via DMT1

  17. Zebrafish (Danio rerio) fed vitamin E deficient diets produce embryos with increased morphologic abnormalities and mortality

    OpenAIRE

    Galen W Miller; Labut, Edwin M.; Lebold, Katie M.; Floeter, Abby; Tanguay, Robert L.; Traber, Maret G.

    2011-01-01

    Vitamin E (α-tocopherol) is required to prevent fetal resorption in rodents. To study α–tocopherol’s role in fetal development, a non-placental model is required. Therefore, the zebrafish, an established developmental model organism, was studied by feeding the fish a defined diet with or without added α–tocopherol. Zebrafish (age: 4–6 w) were fed the deficient (E-), sufficient (E+), or lab diet up to 1 y. All groups showed similar growth rates. The exponential rate of α–tocopherol depletion u...

  18. The Zebrafish Neurophenome Database (ZND): a dynamic open-access resource for zebrafish neurophenotypic data.

    Science.gov (United States)

    Kyzar, Evan; Zapolsky, Ivan; Green, Jeremy; Gaikwad, Siddharth; Pham, Mimi; Collins, Christopher; Roth, Andrew; Stewart, Adam Michael; St-Pierre, Paul; Hirons, Budd; Kalueff, Allan V

    2012-03-01

    Zebrafish (Danio rerio) are widely used in neuroscience research, where their utility as a model organism is rapidly expanding. Low cost, ease of experimental manipulations, and sufficient behavioral complexity make zebrafish a valuable tool for high-throughput studies in biomedicine. To complement the available repositories for zebrafish genetic information, there is a growing need for the collection of zebrafish neurobehavioral and neurological phenotypes. For this, we are establishing the Zebrafish Neurophenome Database (ZND; www.tulane.edu/∼znpindex/search ) as a new dynamic online open-access data repository for behavioral and related physiological data. ZND, currently focusing on adult zebrafish, combines zebrafish neurophenotypic data with a simple, easily searchable user interface, which allow scientists to view and compare results obtained by other laboratories using various treatments in different testing paradigms. As a developing community effort, ZND is expected to foster innovative research using zebrafish by federating the growing body of zebrafish neurophenotypic data.

  19. Uptake of platinum by zebrafish (Danio rerio) and ramshorn snail (Marisa cornuarietis) and resulting effects on early embryogenesis.

    Science.gov (United States)

    Osterauer, Raphaela; Haus, Nadine; Sures, Bernd; Köhler, Heinz-R

    2009-11-01

    Platinum group elements (PGEs), platinum, palladium and rhodium are widely used in automobile catalytic converters. PGEs are emitted into the environment and enter the aquatic ecosystem via runoff rainwater. The present study investigated the bioavailability of platinum chloride for the zebrafish (Danio rerio) and the ramshorn snail (Marisa cornuarietis) and determined the bioaccumulation rate of platinum. Applying the fish early life stage assay for D. rerio (DarT) and the Marisa embryo toxicity test ("Mariett") for M. cornuarietis, effects of platinum chloride on the embryonic development were investigated. Platinum concentrations tested in this study ranged from environmentally relevant concentrations of 38 ng L(-1) up to a concentration of 74.2 microg L(-1) for D. rerio and of 200 ngL(-1) up to 98.7 microg L(-1) for M. cornuarietis. Platinum was found to be accumulated in both organisms. Bioaccumulation factors (BAFs) were in the range of 5-55 for D. rerio and of 218.4-723.9 for M. cornuarietis, depending on the tested Pt concentrations. During the embryonic development, platinum was shown to alter the heart rate of both organisms already at the lowest tested concentration. At higher concentrations, platinum decelerated the hatching rate of the embryos of both species. Additionally, a retardation of the general development and a loss of weight due to platinum exposure was observed in M. cornuarietis. Results of this study contribute important data on the ecotoxicity of a rarely studied element.

  20. The influence of magnetic field on the spatial orientation in zebrafish Danio rerio (Hamilton and roach Rutilus rutilus (L.

    Directory of Open Access Journals (Sweden)

    Anastasia A. Batrakova

    2015-11-01

    Full Text Available Known, that some teleostei can perceive the geomagnetic field (GMF. However, the information about magnetosensitivity in Cyprinidae fish from artificial and natural habitats is obscure. We have registered preferred directions in Danio rerio (Hamilton from aquaria-cultivated line exposed to the natural GMF, 180 degrees reversal of horizontal GMF component, 180 degrees reversal of vertical GMF component, 180 degrees reversal of both vertical and horizontal GMF components and 90 degrees clockwise turn of horizontal GMF component. We also registered the preferred directions in Rutilus rutilus (L. from Rybinsk reservoir exposed to the natural GMF and 90 degrees clockwise turn of horizontal GMF component. It was found that zebrafish prefer two opposite directions towards east and west in the natural GMF. When the horizontal component of GMF was turned 90 degrees clockwise D. rerio prefer two opposite directions towards north and south. The possible reason of bimodality in zebrafish’s preferred directions distributions is discussed. The only direction towards east-north-east observed in roach under the natural GMF. This direction coincided with the way from the place of capture to the streamflow part of Rybinsk reservoir. And it was changed by south-south-east direction when turned the horizontal component of GMF 90 degrees clockwise. The possible reason of the choosing directions by fish with GMF is discussed.

  1. Uptake of platinum by zebrafish (Danio rerio) and ramshorn snail (Marisa cornuarietis) and resulting effects on early embryogenesis.

    Science.gov (United States)

    Osterauer, Raphaela; Haus, Nadine; Sures, Bernd; Köhler, Heinz-R

    2009-11-01

    Platinum group elements (PGEs), platinum, palladium and rhodium are widely used in automobile catalytic converters. PGEs are emitted into the environment and enter the aquatic ecosystem via runoff rainwater. The present study investigated the bioavailability of platinum chloride for the zebrafish (Danio rerio) and the ramshorn snail (Marisa cornuarietis) and determined the bioaccumulation rate of platinum. Applying the fish early life stage assay for D. rerio (DarT) and the Marisa embryo toxicity test ("Mariett") for M. cornuarietis, effects of platinum chloride on the embryonic development were investigated. Platinum concentrations tested in this study ranged from environmentally relevant concentrations of 38 ng L(-1) up to a concentration of 74.2 microg L(-1) for D. rerio and of 200 ngL(-1) up to 98.7 microg L(-1) for M. cornuarietis. Platinum was found to be accumulated in both organisms. Bioaccumulation factors (BAFs) were in the range of 5-55 for D. rerio and of 218.4-723.9 for M. cornuarietis, depending on the tested Pt concentrations. During the embryonic development, platinum was shown to alter the heart rate of both organisms already at the lowest tested concentration. At higher concentrations, platinum decelerated the hatching rate of the embryos of both species. Additionally, a retardation of the general development and a loss of weight due to platinum exposure was observed in M. cornuarietis. Results of this study contribute important data on the ecotoxicity of a rarely studied element. PMID:19796790

  2. Mitochondrial energetic metabolism perturbations in skeletal muscles and brain of zebrafish (Danio rerio) exposed to low concentrations of waterborne uranium

    Energy Technology Data Exchange (ETDEWEB)

    Lerebours, Adelaide; Adam-Guillermin, Christelle [Laboratoire de Radioecologie et d' Ecotoxicologie, Institut de Radioprotection et de Surete Nucleaire, Bat 186, BP 3, 13115 Saint-Paul-Lez-Durance Cedex (France); Brethes, Daniel [CNRS, UMR 5095, Institut de Biochimie et Genetique Cellulaires, Universite Victor Segalen-Bordeaux 2 (France); Frelon, Sandrine; Floriani, Magali; Camilleri, Virginie; Garnier-Laplace, Jacqueline [Laboratoire de Radioecologie et d' Ecotoxicologie, Institut de Radioprotection et de Surete Nucleaire, Bat 186, BP 3, 13115 Saint-Paul-Lez-Durance Cedex (France); Bourdineaud, Jean-Paul, E-mail: jp.bourdineaud@epoc.u-bordeaux1.fr [CNRS, UMR 5095, Institut de Biochimie et Genetique Cellulaires, Universite Victor Segalen-Bordeaux 2 (France)

    2010-10-01

    Anthropogenic release of uranium (U), originating from the nuclear fuel cycle or military activities, may considerably increase U concentrations in terrestrial and aquatic ecosystems above the naturally occurring background levels found throughout the environment. With a projected increase in the world-wide use of nuclear power, it is important to improve our understanding of the possible effects of this metal on the aquatic fauna at concentrations commensurate with the provisional drinking water guideline value of the World Health Organization (15 {mu}g U/L). The present study has examined the mitochondrial function in brain and skeletal muscles of the zebrafish, Danio rerio, exposed to 30 and 100 {mu}g/L of waterborne U for 10 and 28 days. At the lower concentration, the basal mitochondrial respiration rate was increased in brain at day 10 and in muscles at day 28. This is due to an increase of the inner mitochondrial membrane permeability, resulting in a decrease of the respiratory control ratio. In addition, levels of cytochrome c oxidase subunit IV (COX-IV) increased in brain at day 10, and those of COX-I increased in muscles at day 28. Histological analyses performed by transmission electron microscopy revealed an alteration of myofibrils and a dilatation of endomysium in muscle cells. These effects were largest at the lowest concentration, following 28 days of exposure.

  3. Back to basics: searching for a comprehensive framework for exploring individual differences in zebrafish (Danio rerio) behavior.

    Science.gov (United States)

    Toms, Christina N; Echevarria, David J

    2014-08-01

    Individual differences (IDs) in behavior among nonhuman animals have been documented in a wide range of taxa. Although traditionally considered noise around an average, other potentially adaptive sources of phenotypic variation exist. IDs in behavior that are consistent across time and context are more recently recognized as expressions of underlying personality traits, which may even be heritable. Unfortunately, despite the rapid advances that have been made in animal personality research utilizing fish the last decade, a few have detailed the groundwork necessary to document consistency in behavior across time and context. This foundation is required, by definition, before one can draw conclusions about personality traits. Here, we examine whether IDs in behavior are consistent over time and across contexts and explore the construct validity of six commonly used behavioral assays for examining four personality traits: aggression, boldness, fear, and exploration. Thirty zebrafish (Danio rerio) were exposed twice each to a small open field, large open field, mirror, emergence, novel object, and predator response test. Results revealed consistency in most behavioral measures across both time and context. There was mixed evidence for the construct validity of these assays in capturing the targeted personality traits. PMID:24921670

  4. Mitochondrial energetic metabolism perturbations in skeletal muscles and brain of zebrafish (Danio rerio) exposed to low concentrations of waterborne uranium

    International Nuclear Information System (INIS)

    Anthropogenic release of uranium (U), originating from the nuclear fuel cycle or military activities, may considerably increase U concentrations in terrestrial and aquatic ecosystems above the naturally occurring background levels found throughout the environment. With a projected increase in the world-wide use of nuclear power, it is important to improve our understanding of the possible effects of this metal on the aquatic fauna at concentrations commensurate with the provisional drinking water guideline value of the World Health Organization (15 μg U/L). The present study has examined the mitochondrial function in brain and skeletal muscles of the zebrafish, Danio rerio, exposed to 30 and 100 μg/L of waterborne U for 10 and 28 days. At the lower concentration, the basal mitochondrial respiration rate was increased in brain at day 10 and in muscles at day 28. This is due to an increase of the inner mitochondrial membrane permeability, resulting in a decrease of the respiratory control ratio. In addition, levels of cytochrome c oxidase subunit IV (COX-IV) increased in brain at day 10, and those of COX-I increased in muscles at day 28. Histological analyses performed by transmission electron microscopy revealed an alteration of myofibrils and a dilatation of endomysium in muscle cells. These effects were largest at the lowest concentration, following 28 days of exposure.

  5. Neutrophil Migration in the Activation of the Innate Immune Response to Different Flavobacterium psychrophilum Vaccines in Zebrafish (Danio rerio

    Directory of Open Access Journals (Sweden)

    Camila J. Solís

    2015-01-01

    Full Text Available Flavobacterium psychrophilum is a Gram-negative bacterium, responsible for the bacterial cold-water disease and the rainbow trout fry syndrome in freshwater salmonid fish. At present, there is only one commercial vaccine in Chile, made with two Chilean F. psychrophilum isolates and another licensed in Europe. The present study analyzed neutrophil migration, as a marker of innate immune activation, in zebrafish (Danio rerio in response to different F. psychrophilum bath vaccines, which is the first step in evaluating vaccine effectiveness and efficiency in fish. Results indicated that bacterins of the LM-02-Fp isolate were more immunogenic than those from the LM-13-Fp isolate. However, no differences were observed between the same bacteria inactivated by either formaldehyde or heat. Importantly, the same vaccine formulation without an adjuvant only triggered a mild neutrophil migration compared to the complete vaccine. Observations also found that, after a year of storage at 4°C, the activation of the innate immune system by the different vaccines was considerably decreased. Finally, new vaccine formulations prepared with heat and formaldehyde inactivated LM-02-Fp were significantly more efficient than the available commercial vaccine in regard to stimulating the innate immune system.

  6. Bioavailability and bioconcentration potential of perfluoroalkyl-phosphinic and -phosphonic acids in zebrafish (Danio rerio): Comparison to perfluorocarboxylates and perfluorosulfonates.

    Science.gov (United States)

    Chen, Fangfang; Gong, Zhiyuan; Kelly, Barry C

    2016-10-15

    Currently, information regarding bioavailability and bioconcentration potential of perfluoroalkyl phosphinic acids (PFPiAs) in aquatic organisms does not exist. The main objective of the present study was to assess uptake and elimination kinetics of PFPiAs in zebrafish (Danio rerio) following aqueous exposure. The results showed that PFPiA exposure can result in very high steady-state bioconentration factors (BCFss), compared to perfluorocarboxylates and perfluorosulfonates.C6/C10 PFPiA exhibited the highest BCFss, ranging between 10(7) and 10(10), orders of magnitude higher than those for long-chain perfluorocarboxylates. Strong positive relationships were observed between BCFss versus the membrane-water distribution coefficient (Dmw) and the protein-water partition coefficient (Kpw) of the studied perfluoroalkyl substances. However, BCFss exhibited a substantial drop for the very hydrophobic PFPiAs (C8/C10 and C6/C12 PFPiAs). The reduced BCFss of these long-chain PFPiAs (perfluoroalkyl chain length=18; Dmw=10(9)) is likely the result of reduced bioavailability due to interaction with solute molecules/organic matter present in the water phase and/or reduced gill membrane permeability. While PFPiAs can be metabolized to perfluoroalkyl phosphonic acids, the metabolic transformation rate seems insufficient to counteract the high degree of uptake across gill membranes. These findings help to better understand exposure pathways and bioaccumulation behavior of these important perfluorinated acids in aquatic systems. PMID:27285794

  7. Embryonic exposure to cypermethrin induces apoptosis and immunotoxicity in zebrafish (Danio rerio).

    Science.gov (United States)

    Jin, Yuanxiang; Zheng, Shanshan; Fu, Zhengwei

    2011-01-01

    Cypermethrin (CYP) is widely used for control of indoor and field pests. As a result, CYP is one of the most common contaminants in freshwater aquatic systems. In the present study, we investigated the effects of CYP exposure on the induction of apoptosis and immunotoxicity in zebrafish during the embryo developmental stage. The mRNA levels of some key genes including P53, Puma, Bax, Apaf1, Cas9 and Cas3 on the mitochondrial pathway of cell apoptosis were significantly up-regulated at the concentration of 3 and 10 μg/l CYP. Correspondingly, the activities of Cas3 and Cas9 increased significantly after exposure to 3 or 10 μg/l CYP. In addition, the mRNA levels of iNOS and the total content of NO were also up-regulated significantly after CYP exposure. Moreover, it was also observed that the mRNA levels of IFN, CXCL-Clc, CC-chem and C3, which are closely related to the innate immune system, were affected in newly hatched zebrafish when exposed to 3 and 10 μg/l CYP, exhibiting CYP's prominent impacts on the innate immune system of zebrafish. Taken together, our results suggest that CYP has the potential to induce cell apoptosis and cause innate immune system disruption in zebrafish during the embryo stage. The information presented in this study will help elucidate the mechanism of CYP-induced toxicity in fish. PMID:21316461

  8. The dynamics of neutrophils in zebrafish (Danio rerio) during infection with the parasite Ichthyophthirius multifiliis

    DEFF Research Database (Denmark)

    Jørgensen, Louise von Gersdorff

    2016-01-01

    Ichthyophthirius multifiliis is a ciliated protozoan parasite infecting the skin and gills of freshwater fish. Neutrophils are attracted to the infection sites, as a part of the innate immune response. In this study a transgenic line of zebrafish (Tg(MPO:GFP)i114) with GFP-tagged neutrophils...

  9. Conditioned place avoidance of zebrafish (Danio rerio to three chemicals used for euthanasia and anaesthesia.

    Directory of Open Access Journals (Sweden)

    Devina Wong

    Full Text Available Zebrafish are becoming one of the most used vertebrates in developmental and biomedical research. Fish are commonly killed at the end of an experiment with an overdose of tricaine methanesulfonate (TMS, also known as MS-222, but to date little research has assessed if exposure to this or other agents qualifies as euthanasia (i.e. a "good death". Alternative agents include metomidate hydrochloride and clove oil. We use a conditioned place avoidance paradigm to compare aversion to TMS, clove oil, and metomidate hydrochloride. Zebrafish (n = 51 were exposed to the different anaesthetics in the initially preferred side of a light/dark box. After exposure to TMS zebrafish spent less time in their previously preferred side; aversion was less pronounced following exposure to metomidate hydrochloride and clove oil. Nine of 17 fish exposed to TMS chose not to re-enter the previously preferred side, versus 2 of 18 and 3 of 16 refusals for metomidate hydrochloride and clove oil, respectively. We conclude that metomidate hydrochloride and clove oil are less aversive than TMS and that these agents be used as humane alternatives to TMS for killing zebrafish.

  10. Programming of the hypothalamic-pituitary-interrenal axis by maternal social status in zebrafish (Danio rerio).

    Science.gov (United States)

    Jeffrey, Jennifer D; Gilmour, Kathleen M

    2016-06-01

    The present study examined the effects of maternal social status, with subordinate status being a chronic stressor, on development and activity of the stress axis in zebrafish embryos and larvae. Female zebrafish were confined in pairs for 48 h to establish dominant/subordinate hierarchies; their offspring were reared to 144 h post-fertilization (hpf) and sampled at five time points over development. No differences were detected in maternal cortisol contribution, which is thought to be an important programmer of offspring phenotype. However, once zebrafish offspring began to synthesize cortisol de novo (48 hpf), larvae of dominant females exhibited significantly lower baseline cortisol levels than offspring of subordinate females. These lower cortisol levels may reflect reduced hypothalamic-pituitary-interrenal (HPI) axis activity, because corticotropin-releasing factor (crf) and cytochrome p450 side chain cleavage enzyme (p450scc) mRNA levels also were lower in larvae from dominant females. Moreover, baseline mRNA levels of HPI axis genes continued to be affected by maternal social status beyond 48 hpf. At 144 hpf, stress-induced cortisol levels were significantly lower in offspring of subordinate females. These results suggest programming of stress axis function in zebrafish offspring by maternal social status, emphasizing the importance of maternal environment and experience on offspring stress axis activity. PMID:27045091

  11. Targeting and stimulation of the zebrafish (Danio rerio) innate immune system with LPS/dsRNA-loaded nanoliposomes

    OpenAIRE

    Ruyra Ripoll, Àngels; Cano Sarabia, Mary; García-Valtanen, Pablo; Yero Corona, Daniel; Gibert, Isidre; Simon A MacKenzie; Estepa, Amparo; Maspoch Comamala, Daniel; Roher Armentia, Nerea

    2014-01-01

    Herein we report the use of immunostimulant-loaded nanoliposomes (called NLcliposomes) as a strategy to protect fish against bacterial and/or viral infections. This work entailed developing a method for in vivo tracking of the liposomes administered to adult zebrafish that enables evaluation of their in vivo dynamics and characterisation of their tissue distribution. The NLc liposomes, which co-encapsulate poly(I:C) and LPS, accumulate in immune tissues and in immunologically relevant cells s...

  12. Effects of chronic exposure to environmentally relevant concentrations of waterborne depleted uranium on the digestive tract of zebrafish, Danio rerio

    International Nuclear Information System (INIS)

    Uranium is a naturally occurring element, but activities linked to the nuclear fuel cycle can increase background levels in the surrounding waters. For this reason it is important to understand how this affects organisms residing in the water column. The objective of this study was to assess histopathological effects of uranium on the gut wall of a widely used model organism: zebrafish, Danio rerio. To this end we exposed zebrafish to 84 and 420 nM depleted uranium for over a month and then examined the histology of intestines of exposed individuals compared to controls. The gut wall of individuals exposed to 84 and 420 nM of uranium had large regions of degraded mucosa. Using transmission electron microscopy (TEM) coupled to energy-dispersive X-ray spectroscopy microanalysis (EDX) we found that uranium induced a decrease in the amount of calcium containing mitochondrial matrix granules per mitochondria. This is suggestive of perturbations to cellular metabolism and more specifically to cellular calcium homeostasis. TEM-EDX of the gut wall tissue further showed that some uranium was internalized in the nucleus of epithelial cells in the 420 nM treatment. Fluorescent in situ hybridization using specific probes to detect all eubacteria was performed on frozen sections of 6 individual fish in the 84 nM and 420 nM treatments. Bacterial colonization of the gut of individuals in the 420 nM seemed to differ from that of the controls and 84 nM individuals. We suggest that host–microbiota interactions are potentially disturbed in response to uranium induced stress. The damage induced by waterborne uranium to the gut wall did not seem to depend on the concentration of uranium in the media. We measure whole body residues of uranium at the end of the experiment and compute the mean dose rate absorbed for each condition. We discuss why effects might be uncoupled from external concentration and highlight that it is not so much the external concentration but the dynamics

  13. Effects of depleted uranium on the reproductive success and F1 generation survival of zebrafish (Danio rerio)

    Energy Technology Data Exchange (ETDEWEB)

    Bourrachot, Stéphanie [Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-ENV/SERIS/LECO, Cadarache, Saint-Paul-lez-Durance 13115 (France); Brion, François [Institut National de l’Environnement Industriel et des Risques (INERIS), Unité d’évaluation des risques écotoxicologiques, BP2, 60550 Verneuil-en-Halatte (France); Pereira, Sandrine; Floriani, Magali; Camilleri, Virginie; Cavalié, Isabelle [Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-ENV/SERIS/LECO, Cadarache, Saint-Paul-lez-Durance 13115 (France); Palluel, Olivier [Institut National de l’Environnement Industriel et des Risques (INERIS), Unité d’évaluation des risques écotoxicologiques, BP2, 60550 Verneuil-en-Halatte (France); Adam-Guillermin, Christelle, E-mail: christelle.adam-guillermin@irsn.fr [Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-ENV/SERIS/LECO, Cadarache, Saint-Paul-lez-Durance 13115 (France)

    2014-09-15

    Highlights: • The effect of depleted uranium on zebrafish reproduction was studied. • An inhibition of egg production and an increase of F1 embryo mortality were observed. • Decreased circulating concentration of vitellogenin was observed in females. • Increased DNA damages were observed in parent gonads and in embryos. • U environmental concentration impairs reproduction and genetic integrity of fish. - Abstract: Despite the well-characterized occurrence of uranium (U) in the aquatic environment, very little is known about the chronic exposure of fish to low levels of U and its potential effect on reproduction. Therefore, this study was undertaken to investigate the effects of environmental concentrations of depleted U on the reproductive output of zebrafish (Danio rerio) and on survival and development of the F1 embryo-larvae following parental exposure to U. For that purpose, sexually mature male and female zebrafish were exposed to 20 and 250 μg/L of U for 14 days and allowed to reproduce in clean water during a further 14-day period. At all sampling times, whole-body vitellogenin concentrations and gonad histology were analyzed to investigate the effects of U exposure on these reproductive endpoints. In addition, accumulation of U in the gonads and its genotoxic effect on male and female gonad cells were quantified. The results showed that U strongly affected the capability of fish to reproduce and to generate viable individuals as evidenced by the inhibition of egg production and the increased rate of mortality of the F1 embryos. Interestingly, U exposure resulted in decreased circulating concentrations of vitellogenin in females. Increased concentrations of U were observed in gonads and eggs, which were most likely responsible for the genotoxic effects seen in fish gonads and in embryos exposed maternally to U. Altogether, these findings highlight the negative effect of environmentally relevant concentrations of U which alter the reproductive

  14. Subdivisions of the adult zebrafish pallium based on molecular marker analysis [version 2; referees: 2 approved, 1 approved with reservations

    Directory of Open Access Journals (Sweden)

    Julia Ganz

    2015-11-01

    Full Text Available Background: The telencephalon shows a remarkable structural diversity among vertebrates. In particular, the everted telencephalon of ray-finned fishes has a markedly different morphology compared to the evaginated telencephalon of all other vertebrates. This difference in development has hampered the comparison between different areas of the pallium of ray-finned fishes and the pallial nuclei of all other vertebrates. Various models of homology between pallial subdivisions in ray-finned fishes and the pallial nuclei in tetrapods have been proposed based on connectional, neurochemical, gene expression and functional data. However, no consensus has been reached so far. In recent years, the analysis of conserved developmental marker genes has assisted the identification of homologies for different parts of the telencephalon among several tetrapod species. Results: We have investigated the gene expression pattern of conserved marker genes in the adult zebrafish (Danio rerio pallium to identify pallial subdivisions and their homology to pallial nuclei in tetrapods. Combinatorial expression analysis of ascl1a, eomesa, emx1, emx2, emx3, and Prox1 identifies four main divisions in the adult zebrafish pallium. Within these subdivisions, we propose that Dm is homologous to the pallial amygdala in tetrapods and that the dorsal subdivision of Dl is homologous to part of the hippocampal formation in mouse. We have complemented this analysis be examining the gene expression of emx1, emx2 and emx3 in the zebrafish larval brain. Conclusions: Based on our gene expression data, we propose a new model of subdivisions in the adult zebrafish pallium and their putative homologies to pallial nuclei in tetrapods. Pallial nuclei control sensory, motor, and cognitive functions, like memory, learning and emotion. The identification of pallial subdivisions in the adult zebrafish and their homologies to pallial nuclei in tetrapods will contribute to the use of the zebrafish

  15. Startle response memory and hippocampal changes in adult zebrafish pharmacologically-induced to exhibit anxiety/depression-like behaviors.

    Science.gov (United States)

    Pittman, Julian T; Lott, Chad S

    2014-01-17

    Zebrafish (Danio rerio) are rapidly becoming a popular animal model for neurobehavioral and psychopharmacological research. While startle testing is a well-established assay to investigate anxiety-like behaviors in different species, screening of the startle response and its habituation in zebrafish is a new direction of translational biomedical research. This study focuses on a novel behavioral protocol to assess a tapping-induced startle response and its habituation in adult zebrafish that have been pharmacologically-induced to exhibit anxiety/depression-like behaviors. We demonstrated that zebrafish exhibit robust learning performance in a task adapted from the mammalian literature, a modified plus maze, and showed that ethanol and fluoxetine impair memory performance in this maze when administered after training at a dose that does not impair motor function, however, leads to significant upregulation of hippocampal serotoninergic neurons. These results suggest that the maze associative learning paradigm has face and construct validity and that zebrafish may become a translationally relevant study species for the analysis of the mechanisms of learning and memory changes associated with psychopharmacological treatment of anxiety/depression. PMID:24184510

  16. The impact of ZnO nanoparticle aggregates on the embryonic development of zebrafish (Danio rerio)

    Energy Technology Data Exchange (ETDEWEB)

    Zhu Xiaoshan; Zhang Xuezhi; Chen Yongsheng [Department of Civil and Environmental Engineering, Arizona State University, Tempe, AZ 85287 (United States); Wang Jiangxin; Chang Yung [School of Life Sciences, Center for Infectious Diseases and Vaccinology, Biodesign Institute, Arizona State University, Tempe, AZ 85287 (United States)], E-mail: yung.chang@asu.edu, E-mail: yschen@asu.edu

    2009-05-13

    With extensive use of metal oxide nanoparticles (NPs) in a variety of applications comes a higher potential of release into aquatic environments. NPs tend to form much larger aggregates in water, which are expected to settle down to the bottom of the water column and possibly get mixed with the sediments. However, little is known about the environmental impacts and biological effects of these aggregated NPs in the sediment column. In this study, we examined the sedimentation of nanoscale ZnO particles (nZnO) in zebrafish culture medium, and assessed the toxicity of settled nZnO aggregates on developing zebrafish embryos and larvae. Given the known dissolution of nZnO particles to release Zn{sup 2+}, we also assessed the toxic effect of soluble Zn{sup 2+} in this organism. We demonstrated that within 48 h, micron-sized nZnO aggregates were formed and settled out of the culture medium. These aggregates were found to exert dose-dependent toxicity to zebrafish embryos and larvae, reducing the hatching rate and causing pericardial edema. The observed toxicity of the nZnO aggregates was not likely a result solely of particle dissolution, as soluble Zn{sup 2+} alone caused much less toxicity to zebrafish embryos than nZnO. Instead, the combination of both nZnO and Zn{sup 2+} may contribute to the embryonic toxicity, possibly by increasing reactive oxidative species (ROS) and/or compromising the cellular oxidative stress response. Interestingly, we demonstrated that one type of formulated sediments could mitigate the toxicity of nZnO aggregates, highlighting a possible countermeasure to reduce the adverse impact of nZnO aggregates on the environment.

  17. Brain transcriptome variation among behaviorally distinct strains of zebrafish (Danio rerio

    Directory of Open Access Journals (Sweden)

    Drew Robert E

    2012-07-01

    Full Text Available Abstract Background Domesticated animal populations often show profound reductions in predator avoidance and fear-related behavior compared to wild populations. These reductions are remarkably consistent and have been observed in a diverse array of taxa including fish, birds, and mammals. Experiments conducted in common environments indicate that these behavioral differences have a genetic basis. In this study, we quantified differences in fear-related behavior between wild and domesticated zebrafish strains and used microarray analysis to identify genes that may be associated with this variation. Results Compared to wild zebrafish, domesticated zebrafish spent more time near the water surface and were more likely to occupy the front of the aquarium nearest a human observer. Microarray analysis of the brain transcriptome identified high levels of population variation in gene expression, with 1,749 genes significantly differentially expressed among populations. Genes that varied among populations belonged to functional categories that included DNA repair, DNA photolyase activity, response to light stimulus, neuron development and axon guidance, cell death, iron-binding, chromatin reorganization, and homeobox genes. Comparatively fewer genes (112 differed between domesticated and wild strains with notable genes including gpr177 (wntless, selenoprotein P1a, synaptophysin and synaptoporin, and acyl-CoA binding domain containing proteins (acbd3 and acbd4. Conclusions Microarray analysis identified a large number of genes that differed among zebrafish populations and may underlie behavioral domestication. Comparisons with similar microarray studies of domestication in rainbow trout and canids identified sixteen evolutionarily or functionally related genes that may represent components of shared molecular mechanisms underlying convergent behavioral evolution during vertebrate domestication. However, this conclusion must be tempered by limitations

  18. Uranium bioaccumulation and biological disorders induced in zebrafish (Danio rerio) after a depleted uranium waterborne exposure

    Energy Technology Data Exchange (ETDEWEB)

    Barillet, Sabrina, E-mail: sabrina.barillet@free.f [Laboratory of Radioecology and Ecotoxicology, IRSN (Institute for Radiological protection and Nuclear Safety), DEI/SECRE/LRE, Cadarache, Bat 186, BP 3, 13115 St-Paul-Lez-Durance cedex (France); Adam-Guillermin, Christelle, E-mail: christelle.adam-guillermin@irsn.f [Laboratory of Radioecology and Ecotoxicology, IRSN (Institute for Radiological protection and Nuclear Safety), DEI/SECRE/LRE, Cadarache, Bat 186, BP 3, 13115 St-Paul-Lez-Durance cedex (France); Palluel, Olivier, E-mail: olivier.palluel@ineris.f [Ecotoxicological Risk Assessment Unit, INERIS (National Institute for Industrial Environment and Risks), Parc technologique ALATA, 60 550 Verneuil-en-Halatte (France); Porcher, Jean-Marc, E-mail: jean-marc.porcher@ineris.f [Ecotoxicological Risk Assessment Unit, INERIS (National Institute for Industrial Environment and Risks), Parc technologique ALATA, 60 550 Verneuil-en-Halatte (France); Devaux, Alain, E-mail: alain.devaux@entpe.f [Universite de Lyon, INRA, EFPA-SA, Environmental Science Laboratory (LSE), ENTPE, 69518 Vaulx en Velin cedex (France)

    2011-02-15

    Because of its toxicity and its ubiquity within aquatic compartments, uranium (U) represents a significant hazard to aquatic species such as fish. In a previous study, we investigated some biological responses in zebrafish either exposed to depleted or to enriched U (i.e., to different radiological activities). However, results required further experiments to better understand biological responses. Moreover, we failed to clearly demonstrate a significant relationship between biological effects and U radiological activity. We therefore chose to herein examine U bioaccumulation and induced effects in zebrafish according to a chemical dose-response approach. Results showed that U is highly bioconcentrated in fish, according to a time- and concentration-dependent model. Additionally, hepatic antioxidant defenses, red blood cells DNA integrity and brain acetylcholinesterase activity were found to be significantly altered. Generally, the higher the U concentration, the sooner and/or the greater the effect, suggesting a close relationship between accumulation and effect. - Research highlights: Depleted U bioconcentration factor is of about 1000 in zebrafish exposed to 20 {mu}g/L. Hepatic antioxidant disorders are noticed as soon as the first hours of exposure. DNA damage is induced in red blood cells after 20 d of exposure to 500 {mu}g DU/L. The brain cholinergic system (AChE activity) is impacted. - This study demonstrates that U is highly bioaccumulated in fish, resulting in biological disorders such as hepatic oxidative stress as well as genotoxic and neurotoxic events.

  19. Atrazine and its main metabolites alter the locomotor activity of larval zebrafish (Danio rerio).

    Science.gov (United States)

    Liu, Zhenzhen; Wang, Yueyi; Zhu, Zhihong; Yang, Enlu; Feng, Xiayan; Fu, Zhengwei; Jin, Yuanxiang

    2016-04-01

    Atrazine (ATZ) and its main chlorometabolites, i.e., diaminochlorotriazine (DACT), deisopropylatrazine (DIP), and deethylatrazine (DE), have been widely detected in aquatic systems near agricultural fields. However, their possible effects on aquatic animals are still not fully understood. In this study, it was observed that several developmental endpoints such as the heart beat, hatchability, and morphological abnormalities were influenced by ATZ and its metabolites in different developmental stages. In addition, after 5 days of exposure to 30, 100, 300 μg L(-1) ATZ and its main chlorometabolites, the swimming behaviors of larval zebrafish were significantly disturbed, and the acetylcholinesterase (AChE) activities were consistently inhibited. Our results also demonstrate that ATZ and its main chlorometabolites are neuroendocrine disruptors that impact the expression of neurotoxicity-related genes such as Ache, Gap43, Gfap, Syn2a, Shha, Mbp, Elavl3, Nestin and Ngn1 in early developmental stages of zebrafish. According to our results, it is possible that not only ATZ but also its metabolites (DACT, DIP and DE) have the same or even more toxic effects on different endpoints of the early developmental stages of zebrafish.

  20. Uranium bioaccumulation and biological disorders induced in zebrafish (Danio rerio) after a depleted uranium waterborne exposure

    International Nuclear Information System (INIS)

    Because of its toxicity and its ubiquity within aquatic compartments, uranium (U) represents a significant hazard to aquatic species such as fish. In a previous study, we investigated some biological responses in zebrafish either exposed to depleted or to enriched U (i.e., to different radiological activities). However, results required further experiments to better understand biological responses. Moreover, we failed to clearly demonstrate a significant relationship between biological effects and U radiological activity. We therefore chose to herein examine U bioaccumulation and induced effects in zebrafish according to a chemical dose-response approach. Results showed that U is highly bioconcentrated in fish, according to a time- and concentration-dependent model. Additionally, hepatic antioxidant defenses, red blood cells DNA integrity and brain acetylcholinesterase activity were found to be significantly altered. Generally, the higher the U concentration, the sooner and/or the greater the effect, suggesting a close relationship between accumulation and effect. - Research highlights: → Depleted U bioconcentration factor is of about 1000 in zebrafish exposed to 20 μg/L. → Hepatic antioxidant disorders are noticed as soon as the first hours of exposure. → DNA damage is induced in red blood cells after 20 d of exposure to 500 μg DU/L. → The brain cholinergic system (AChE activity) is impacted. - This study demonstrates that U is highly bioaccumulated in fish, resulting in biological disorders such as hepatic oxidative stress as well as genotoxic and neurotoxic events.

  1. Embryonic exposure to butachlor in zebrafish (Danio rerio): endocrine disruption, developmental toxicity and immunotoxicity.

    Science.gov (United States)

    Tu, Wenqing; Niu, Lili; Liu, Weiping; Xu, Chao

    2013-03-01

    Butachlor is a chloroacetanilide herbicide widely employed in weeding important crops. Recently, the study of the possible toxic effects of butachlor in non-target organisms has increased substantially. However, the endocrine disruption, developmental toxicity and immunotoxicity effects of butachlor in fish have not been fully investigated in previous studies. In the present study, zebrafish embryos were exposed to a range of butachlor concentrations from 4 to 20 μM to evaluate the embryonic toxicity of butachlor until 84 hours postfertilization (hpf). The results demonstrated that butachlor was highly toxic to zebrafish embryos, hindering the hatching process, resulting in a series of malformations and followed by mortality. The malformations observed included pericardial edema (PE) and yolk sac edema (YSE), which showed concentration-dependent responses. The analysis of endocrine gene transcription indicated that butachlor significantly induced the expression of the estrogen-responsive gene Vtg1 but had no effect on the expression of the ERα gene. The innate immune system appeared to be another possible target of butachlor. At 72 hpf, butachlor significantly up-regulated the innate immune system-related genes, including IL-1β, CC-chem, CXCL-C1c and IL-8. These data suggest that butachlor causes developmental toxicity, endocrine disruption and immune toxicity in the zebrafish embryo. Bidirectional interactions between the endocrine system and the immune system might be present, and further studies are needed to determine these possible pathways. PMID:23294635

  2. Effects of Atrazine on the Development of Neural System of Zebrafish, Danio rerio

    Directory of Open Access Journals (Sweden)

    Hao Wang

    2015-01-01

    Full Text Available By comparative analysis of histomorphology and AChE activity, the changes of physiological and biochemical parameters were determined in zebrafish embryos and larvae dealt with atrazine (ATR at different concentrations (0.0001, 0.001, 0.01, 0.1, and 1 mg/L. This study showed that the development of the sarcomere and the arrangement of white muscle myofibers were affected by ATR significantly and the length of sarcomere shortened. Further analysis of the results showed that the AChE activity in juvenile fish which was treated with ATR was downregulated, which can indicate that the innervation efficiency to the muscle was impaired. Conversely, the AChE activity in zebrafish embryos which was treated with ATR was upregulated. A parallel phenomenon showed that embryonic primary sensory neurons (Rohon-Beard cells, principally expressing AChE in embryos, survived the physiological apoptosis. These phenomena demonstrated that the motor integration ability of the zebrafish was damaged by ATR which can disturb the development of sensory neurons and sarcomere and the innervations of muscle.

  3. Embryonic exposure to butachlor in zebrafish (Danio rerio): endocrine disruption, developmental toxicity and immunotoxicity.

    Science.gov (United States)

    Tu, Wenqing; Niu, Lili; Liu, Weiping; Xu, Chao

    2013-03-01

    Butachlor is a chloroacetanilide herbicide widely employed in weeding important crops. Recently, the study of the possible toxic effects of butachlor in non-target organisms has increased substantially. However, the endocrine disruption, developmental toxicity and immunotoxicity effects of butachlor in fish have not been fully investigated in previous studies. In the present study, zebrafish embryos were exposed to a range of butachlor concentrations from 4 to 20 μM to evaluate the embryonic toxicity of butachlor until 84 hours postfertilization (hpf). The results demonstrated that butachlor was highly toxic to zebrafish embryos, hindering the hatching process, resulting in a series of malformations and followed by mortality. The malformations observed included pericardial edema (PE) and yolk sac edema (YSE), which showed concentration-dependent responses. The analysis of endocrine gene transcription indicated that butachlor significantly induced the expression of the estrogen-responsive gene Vtg1 but had no effect on the expression of the ERα gene. The innate immune system appeared to be another possible target of butachlor. At 72 hpf, butachlor significantly up-regulated the innate immune system-related genes, including IL-1β, CC-chem, CXCL-C1c and IL-8. These data suggest that butachlor causes developmental toxicity, endocrine disruption and immune toxicity in the zebrafish embryo. Bidirectional interactions between the endocrine system and the immune system might be present, and further studies are needed to determine these possible pathways.

  4. Effects of Short-Term Exposure to Sublethal Concentrations of Silver Nanoparticles on Histopathology and Electron Microscope Ultrastructure of Zebrafish (Danio Rerio Gills

    Directory of Open Access Journals (Sweden)

    Borhan Mansouri

    2015-11-01

    Full Text Available Background: The increasing use of nanomaterials and nanoproducts has increased the possibility of contamination of the environment, which may have adverse effects on different organisms. The aim of this study was to evaluate the effects of silver nanoparticles on histopathology and gill ultrastructure of zebrafish (Danio rerio under laboratory conditions. Methods: Zebrafish were exposed to four concentrations of silver nanoparticles (0.0015, 0.00375, 0.0075, and 0.015 mg/l for a period of 4 days. Gill ultrastructure and histopathological changes were studied using scanning electron microscope and haematoxylin - eosin staining. Results: Exposure to silver nanoparticles significantly (P < 0.001 increased the diameter of gill filaments and secondary lamellae, while silver nanoparticles significantly reduced the length of the secondary gills in zebrafish. Moreover, other changes such as vacuolization, dilated and clubbed tips, hyperplasia, edema, fusion, swelling of mucocytes, hypertrophy, and necrosis were observed. The effects of silver nanoparticles in zebrafish gills were dose dependent. Conclusion: Based on the adverse effects of AgNPs on zebrafish gills, silver nanoparticle solutions can be hazardous pollutants for the environment.

  5. A characterization of the ZFL cell line and primary hepatocytes as in vitro liver cell models for the zebrafish (Danio rerio)

    Energy Technology Data Exchange (ETDEWEB)

    Eide, Marta, E-mail: marta.eide@bio.uib.no [Department of Biology, University of Bergen, Bergen (Norway); Rusten, Marte; Male, Rune [Department of Molecular Biology, University of Bergen, Bergen (Norway); Jensen, Knut Helge Midtbø; Goksøyr, Anders [Department of Biology, University of Bergen, Bergen (Norway)

    2014-02-15

    Highlights: •The ZFL cell line and primary hepatocytes were characterized. •Basic and induced expression of nuclear receptors and target genes were found. •The ZFL cell line expresses very low basic levels of most genes. •The ZFL cells have low induction of gene expression following exposures. •Primary hepatocytes show large sex-dependent differences in gene expression. -- Abstract: The zebrafish (Danio rerio) is a widely used model species in biomedical research. The ZFL cell line, established from zebrafish liver, and freshly isolated primary hepatocytes from zebrafish have been used in several toxicological studies. However, no previous report has compared and characterized these two systems at the level of gene expression. The aim of this study was to evaluate the ZFL cell line in comparison to primary hepatocytes as in vitro models for studying effects of environmental contaminants in zebrafish liver. Using quantitative real-time PCR, the basal level and transcriptional induction potential of key genes involved in toxic responses in the ZFL cell line, primary hepatocytes and whole liver from zebrafish were compared. The study showed that the ZFL cells have lower levels of mRNA of most selected genes compared to zebrafish liver. The induced gene transcription following exposure to ligand was much lower in ZFL cells compared to zebrafish primary hepatocytes at the doses tested. Importantly, oestrogen receptor and vitellogenin genes showed low basal transcription and no induction response in the ZFL cell line. In conclusion, it appears that primary hepatocytes are well suited for studying environmental contaminants including xenoestrogens, but may show large sex-dependent differences in gene transcription. The ZFL cell line shows potential in toxicological studies involving the aryl hydrocarbon receptor pathway. However, low potential for transcriptional induction of genes in general should be expected, especially notable when studying estrogenic

  6. Teratogenic, bioenergetic, and behavioral effects of exposure to total particulate matter on early development of zebrafish (Danio rerio) are not mimicked by nicotine

    Science.gov (United States)

    Massarsky, Andrey; Jayasundara, Nishad; Bailey, Jordan M.; Oliveri, Anthony N.; Levin, Edward D.; Prasad, G.L.; Di Giulio, Richard T.

    2016-01-01

    Cigarette smoke has been associated with a number of pathologies; however, the mechanisms leading to developmental effects are yet to be fully understood. The zebrafish embryo is regarded as a ‘bridge model’; however, not many studies examined its applicability to cigarette smoke toxicity. This study examined the effects of total particulate matter (TPM) from 3R4F reference cigarettes on the early development of zebrafish (Danio rerio). Zebrafish embryos were exposed to two concentrations of TPM (0.4 and 1.4 μg/mL equi-nicotine units) or nicotine at equivalent doses. The exposures began at 2 h post-fertilization (hpf) and lasted until 96 hpf. Several physiological parameters were assessed during or after the exposure. We show that TPM increased mortality, delayed hatching, and increased the incidence of deformities in zebrafish. TPM exposure also increased the incidence of hemorrhage and disrupted the angiogenesis of the major vessels in the brain. Moreover, TPM exposure reduced the larval body length, decreased the heart rate, and reduced the metabolic rate. Biomarkers of xenobiotic metabolism and oxidative stress were also affected. TPM-exposed zebrafish also differed behaviorally: at 24 hpf the embryos had a higher frequency of spontaneous contractions and at 144 hpf the larvae displayed swimming hyperactivity. This study demonstrates that TPM disrupts several aspects of early development in zebrafish. The effects reported for TPM were not attributable to nicotine, since embryos treated with nicotine alone did not differ significantly from the control group. Collectively, our work illustrates the utility of zebrafish as an alternative model to evaluate the toxic effects of cigarette smoke constituents. PMID:26391568

  7. Teratogenic, bioenergetic, and behavioral effects of exposure to total particulate matter on early development of zebrafish (Danio rerio) are not mimicked by nicotine.

    Science.gov (United States)

    Massarsky, Andrey; Jayasundara, Nishad; Bailey, Jordan M; Oliveri, Anthony N; Levin, Edward D; Prasad, G L; Di Giulio, Richard T

    2015-01-01

    Cigarette smoke has been associated with a number of pathologies; however, the mechanisms leading to developmental effects are yet to be fully understood. The zebrafish embryo is regarded as a 'bridge model'; however, not many studies examined its applicability to cigarette smoke toxicity. This study examined the effects of total particulate matter (TPM) from 3R4F reference cigarettes on the early development of zebrafish (Danio rerio). Zebrafish embryos were exposed to two concentrations of TPM (0.4 and 1.4 μg/mL equi-nicotine units) or nicotine at equivalent doses. The exposures began at 2h post-fertilization (hpf) and lasted until 96 hpf. Several physiological parameters were assessed during or after the exposure. We show that TPM increased mortality, delayed hatching, and increased the incidence of deformities in zebrafish. TPM exposure also increased the incidence of hemorrhage and disrupted the angiogenesis of the major vessels in the brain. Moreover, TPM exposure reduced the larval body length, decreased the heart rate, and reduced the metabolic rate. Biomarkers of xenobiotic metabolism and oxidative stress were also affected. TPM-exposed zebrafish also differed behaviorally: at 24 hpf the embryos had a higher frequency of spontaneous contractions and at 144 hpf the larvae displayed swimming hyperactivity. This study demonstrates that TPM disrupts several aspects of early development in zebrafish. The effects reported for TPM were not attributable to nicotine, since embryos treated with nicotine alone did not differ significantly from the control group. Collectively, our work illustrates the utility of zebrafish as an alternative model to evaluate the toxic effects of cigarette smoke constituents.

  8. Oxidative stress and regulation of Pink1 in zebrafish (Danio rerio.

    Directory of Open Access Journals (Sweden)

    Madhusmita Priyadarshini

    Full Text Available Oxidative stress-mediated neuronal dysfunction is characteristic of several neurodegenerative disorders, including Parkinson's disease (PD. The enzyme tyrosine hydroxylase (TH catalyzes the formation of L-DOPA, the rate-limiting step in the biosynthesis of dopamine. A lack of dopamine in the striatum is the most characteristic feature of PD, and the cause of the most dominant symptoms. Loss of function mutations in the PTEN-induced putative kinase (PINK1 gene cause autosomal recessive PD. This study explored the basic mechanisms underlying the involvement of pink1 in oxidative stress-mediated PD pathology using zebrafish as a tool. We generated a transgenic line, Tg(pink1:EGFP, and used it to study the effect of oxidative stress (exposure to H2O2 on pink1 expression. GFP expression was enhanced throughout the brain of zebrafish larvae subjected to oxidative stress. In addition to a widespread increase in pink1 mRNA expression, mild oxidative stress induced a clear decline in tyrosine hydroxylase 2 (th2, but not tyrosine hydroxylase 1 (th1 expression, in the brain of wild-type larvae. The drug L-Glutathione Reduced (LGR has been associated with anti-oxidative and possible neuroprotective properties. Administration of LGR normalized the increased fluorescence intensity indicating pink1 transgene expression and endogenous pink1 mRNA expression in larvae subjected to oxidative stress by H2O2. In the pink1 morpholino oliogonucleotide-injected larvae, the reduction in the expression of th1 and th2 was partially rescued by LGR. The pink1 gene is a sensitive marker of oxidative stress in zebrafish, and LGR effectively normalizes the consequences of mild oxidative stress, suggesting that the neuroprotective effects of pink1 and LGR may be significant and useful in drug development.

  9. Differences in sexual development in inbred and outbred zebrafish (Danio rerio) and implications for chemical testing.

    Science.gov (United States)

    Brown, A Ross; Bickley, Lisa K; Ryan, Thomas A; Paull, Gregory C; Hamilton, Patrick B; Owen, Stewart F; Sharpe, Alan D; Tyler, Charles R

    2012-05-15

    Outbred laboratory animal strains used in ecotoxicology are intended to represent wild populations. However, breeding history may vary considerably between strains, driving differences in genetic variation and phenotypes used for assessing effects of chemical exposure. We compared a range of phenotypic endpoints in zebrafish from four different "breeding treatments" comprising a Wild Indian Karyotype (WIK) zebrafish strain and a WIK/Wild strain with three levels of inbreeding (F(IT)=n, n+0.25, n+0.375) in a new Fish Sexual Development Test (FSDT). There were no differences between treatments in terms of egg viability, hatch success or fry survival. However, compared with WIKs, WIK/Wild hybrids were significantly larger in size, with more advanced gonadal (germ cell) development at the end of the test (63 days post fertilisation). Increasing the levels of inbreeding in the related WIK/Wild lines did not affect body size, but there was a significant male-bias (72%) in the most inbred line (F(IT)=n+0.375). Conversely, in the reference WIK strain there was a significant female-bias in the population (80% females). Overall, our results support the use of outbred zebrafish strains in the FSDT, where one of the core endpoints is sex ratio. Despite increased variance (and reduced statistical power) for some endpoints, WIK/Wild outbreds (F(IT)=n) met all acceptance criteria for controls in this test, whereas WIKs failed to comply with tolerance limits for sex ratio (30-70% females). Sexual development was also more advanced in WIK/Wild outbreds (cf. WIKs), providing greater scope for detection of developmental reproductive toxicity following chemical exposure.

  10. Swim-training changes the spatio-temporal dynamics of skeletogenesis in zebrafish larvae (Danio rerio).

    Science.gov (United States)

    Fiaz, Ansa W; Léon-Kloosterziel, Karen M; Gort, Gerrit; Schulte-Merker, Stefan; van Leeuwen, Johan L; Kranenbarg, Sander

    2012-01-01

    Fish larvae experience many environmental challenges during development such as variation in water velocity, food availability and predation. The rapid development of structures involved in feeding, respiration and swimming increases the chance of survival. It has been hypothesized that mechanical loading induced by muscle forces plays a role in prioritizing the development of these structures. Mechanical loading by muscle forces has been shown to affect larval and embryonic bone development in vertebrates, but these investigations were limited to the appendicular skeleton. To explore the role of mechanical load during chondrogenesis and osteogenesis of the cranial, axial and appendicular skeleton, we subjected zebrafish larvae to swim-training, which increases physical exercise levels and presumably also mechanical loads, from 5 until 14 days post fertilization. Here we show that an increased swimming activity accelerated growth, chondrogenesis and osteogenesis during larval development in zebrafish. Interestingly, swim-training accelerated both perichondral and intramembranous ossification. Furthermore, swim-training prioritized the formation of cartilage and bone structures in the head and tail region as well as the formation of elements in the anal and dorsal fins. This suggests that an increased swimming activity prioritized the development of structures which play an important role in swimming and thereby increasing the chance of survival in an environment where water velocity increases. Our study is the first to show that already during early zebrafish larval development, skeletal tissue in the cranial, axial and appendicular skeleton is competent to respond to swim-training due to increased water velocities. It demonstrates that changes in water flow conditions can result into significant spatio-temporal changes in skeletogenesis.

  11. An idiogram on pachytene bivalents with high resolution multiple bands of zebrafish (Danio rerio)

    Institute of Scientific and Technical Information of China (English)

    YI; Meisheng(易梅生); YU; Qixing; (余其兴); HUANG; Lin(黄琳)

    2002-01-01

    Well spread pachytene bivalents with high-resolution multiple bands of zebrafish were obtained after the testes were treated with alkaline hypotonic solution and high chloroform fixative solution. This might be the pattern with the largest number of multiple bands obtained from fish chromosomes so far published. Both the number and character of the bands in each bivalent were stable. According to the principles of ISCN (1978) and ISCN (1981), an idiogram of 599 bands was set up, and the detailed description of the landmark system and the band positions were given.

  12. Effects of acoustic levitation on the development of zebrafish, Danio rerio, embryos

    OpenAIRE

    Maria Sundvik; Nieminen, Heikki J.; Ari Salmi; Pertti Panula; Edward Hæggström

    2015-01-01

    Acoustic levitation provides potential to characterize and manipulate material such as solid particles and fluid in a wall-less environment. While attempts to levitate small animals have been made, the biological effects of such levitation have been scarcely documented. Here, our goal was to explore if zebrafish embryos can be levitated (peak pressures at the pressure node and anti-node: 135 dB and 144 dB, respectively) with no effects on early development. We levitated the embryos (n = 94) a...

  13. Endocrine disruption of courtship behaviour and reproduction in zebrafish (Danio rerio)

    DEFF Research Database (Denmark)

    Broch-Lips, Mia Gina Gruwier

    2011-01-01

    Many different compounds have the abilities to interfere with the endocrine system. The endocrine system in vertebrates is complex and consists of different cross talking systems. Endocrine disruptive chemicals (EDCs) can disturb these systems in various ways, for example by mimicking...... or counteracting the effects endogenous hormones or by interfering with hormone synthesis, transport or metabolism. This thesis deals with the effects of EDCs on the sex steroid system which is a part of the endocrine system and is essential for reproduction and reproductive behaviour. Effects of EDCs on zebrafish...

  14. Strong static magnetic fields elicit swimming behaviors consistent with direct vestibular stimulation in adult zebrafish.

    Directory of Open Access Journals (Sweden)

    Bryan K Ward

    Full Text Available Zebrafish (Danio rerio offer advantages as model animals for studies of inner ear development, genetics and ototoxicity. However, traditional assessment of vestibular function in this species using the vestibulo-ocular reflex requires agar-immobilization of individual fish and specialized video, which are difficult and labor-intensive. We report that using a static magnetic field to directly stimulate the zebrafish labyrinth results in an efficient, quantitative behavioral assay in free-swimming fish. We recently observed that humans have sustained nystagmus in high strength magnetic fields, and we attributed this observation to magnetohydrodynamic forces acting on the labyrinths. Here, fish were individually introduced into the center of a vertical 11.7T magnetic field bore for 2-minute intervals, and their movements were tracked. To assess for heading preference relative to a magnetic field, fish were also placed in a horizontally oriented 4.7T magnet in infrared (IR light. A sub-population was tested again in the magnet after gentamicin bath to ablate lateral line hair cell function. Free-swimming adult zebrafish exhibited markedly altered swimming behavior while in strong static magnetic fields, independent of vision or lateral line function. Two-thirds of fish showed increased swimming velocity or consistent looping/rolling behavior throughout exposure to a strong, vertically oriented magnetic field. Fish also demonstrated altered swimming behavior in a strong horizontally oriented field, demonstrating in most cases preferred swimming direction with respect to the field. These findings could be adapted for 'high-throughput' investigations of the effects of environmental manipulations as well as for changes that occur during development on vestibular function in zebrafish.

  15. Effects of chronic exposure to environmentally relevant concentrations of waterborne depleted uranium on the digestive tract of zebrafish, Danio rerio.

    Science.gov (United States)

    Augustine, Starrlight; Pereira, Sandrine; Floriani, Magali; Camilleri, Virginie; Kooijman, Sebastiaan A L M; Gagnaire, Béatrice; Adam-Guillermin, Christelle

    2015-04-01

    Uranium is a naturally occurring element, but activities linked to the nuclear fuel cycle can increase background levels in the surrounding waters. For this reason it is important to understand how this affects organisms residing in the water column. The objective of this study was to assess histopathological effects of uranium on the gut wall of a widely used model organism: zebrafish, Danio rerio. To this end we exposed zebrafish to 84 and 420 nM depleted uranium for over a month and then examined the histology of intestines of exposed individuals compared to controls. The gut wall of individuals exposed to 84 and 420 nM of uranium had large regions of degraded mucosa. Using transmission electron microscopy (TEM) coupled to energy-dispersive X-ray spectroscopy microanalysis (EDX) we found that uranium induced a decrease in the amount of calcium containing mitochondrial matrix granules per mitochondria. This is suggestive of perturbations to cellular metabolism and more specifically to cellular calcium homeostasis. TEM-EDX of the gut wall tissue further showed that some uranium was internalized in the nucleus of epithelial cells in the 420 nM treatment. Fluorescent in situ hybridization using specific probes to detect all eubacteria was performed on frozen sections of 6 individual fish in the 84 nM and 420 nM treatments. Bacterial colonization of the gut of individuals in the 420 nM seemed to differ from that of the controls and 84 nM individuals. We suggest that host-microbiota interactions are potentially disturbed in response to uranium induced stress. The damage induced by waterborne uranium to the gut wall did not seem to depend on the concentration of uranium in the media. We measure whole body residues of uranium at the end of the experiment and compute the mean dose rate absorbed for each condition. We discuss why effects might be uncoupled from external concentration and highlight that it is not so much the external concentration but the dynamics of

  16. ifferential Gene Expression in Zebrafish (Danio rerio Following Exposure to Gaseous Diffusion Plant Effluent and Effluent Receiving Stream Water

    Directory of Open Access Journals (Sweden)

    Ben F. Brammell

    2010-01-01

    Full Text Available Problem statement: The expression of six genes known to serve as bioindicators of environmental stress were examined using real-time quantitative PCR in liver tissue extracted from zebrafish (Danio rerio, Hamilton exposed to effluent and effluent containing stream water associated with the Paducah Gaseous Diffusion Plant (PGDP. Approach: The PGDP, the only active uranium enrichment facility in the US, is located in western Kentucky and discharges treated effluents into several surrounding streams. Environmentally relevant concentrations of several heavy metals and polychlorinated biphenyls (PCBs can be found in effluents emerging from the plant as well as in receiving streams. Fish were exposed in the laboratory to water from both effluents and downstream areas as well as to water from an upstream reference site. Expression of six genes known to be altered by metal and/or PCB exposure was quantified at both 7 and 14 day time points. Results: Transcription of the biomarker enzyme cytochrome P4501A1 (CYP1A1 was significantly elevated in fish exposed to one plant effluent at both the 7 (16 fold and 14 (10 fold day time points. Sediment PCB levels from this site were the highest observed in the study, indicating PCBs may be contributing to the elevated CYP1A1 mRNA. Additionally, catalase, an enzyme responsible for hydrogen peroxide detoxification and known to be impacted by metal contamination, demonstrated significant alterations in expression in the effluent containing the highest concentrations of most metals observed in this study. Interestingly, despite the presence of metal levels consistent with the induction of metallothionein in other studies, no metallothionein induction was observed. All other stress biomarker encoding genes were likewise unaffected by effluent water exposure. Conclusion/Recommendations: These results indicate that contaminant levels observed in this system altered transcription of catalase and CYP1A1 but failed to

  17. The role of aquaporin and tight junction proteins in the regulation of water movement in larval zebrafish (Danio rerio.

    Directory of Open Access Journals (Sweden)

    Raymond W M Kwong

    Full Text Available Teleost fish living in freshwater are challenged by passive water influx; however the molecular mechanisms regulating water influx in fish are not well understood. The potential involvement of aquaporins (AQP and epithelial tight junction proteins in the regulation of transcellular and paracellular water movement was investigated in larval zebrafish (Danio rerio. We observed that the half-time for saturation of water influx (K(u was 4.3±0.9 min, and reached equilibrium at approximately 30 min. These findings suggest a high turnover rate of water between the fish and the environment. Water influx was reduced by the putative AQP inhibitor phloretin (100 or 500 μM. Immunohistochemistry and confocal microscopy revealed that AQP1a1 protein was expressed in cells on the yolk sac epithelium. A substantial number of these AQP1a1-positive cells were identified as ionocytes, either H⁺-ATPase-rich cells or Na⁺/K⁺-ATPase-rich cells. AQP1a1 appeared to be expressed predominantly on the basolateral membranes of ionocytes, suggesting its potential involvement in regulating ionocyte volume and/or water flux into the circulation. Additionally, translational gene knockdown of AQP1a1 protein reduced water influx by approximately 30%, further indicating a role for AQP1a1 in facilitating transcellular water uptake. On the other hand, incubation with the Ca²⁺-chelator EDTA or knockdown of the epithelial tight junction protein claudin-b significantly increased water influx. These findings indicate that the epithelial tight junctions normally act to restrict paracellular water influx. Together, the results of the present study provide direct in vivo evidence that water movement can occur through transcellular routes (via AQP; the paracellular routes may become significant when the paracellular permeability is increased.

  18. Polybrominated diphenyl ethers affect the reproduction and development, and alter the sex ratio of zebrafish (Danio rerio)

    International Nuclear Information System (INIS)

    Polybrominated diphenyl ethers (PBDEs) have been commonly used as flame retardants and now become ubiquitous in the global environment. Using zebrafish as a model, we tested the hypothesis that PBDEs may affect the reproduction and development of fish. Zebrafish were exposed to environmentally relevant concentrations of DE-71 (a congener of PBDE commonly found in the environment) throughout their whole life cycle, and the effects of DE-71 on gonadal development, gamete quality, fertilization success, hatching success, embryonic development and sex ratio were investigated. Despite gonadal development was enhanced, reductions in spawning, fertilization success, hatching success and larval survival rate were evident, while significant increases in malformation and percentage of male were also observed in the F1 generation. Our laboratory results suggest that PBDEs may pose a risk to reproductive success and alter the sex ratio of fish in environments highly contaminated with PBDEs. -- Highlights: •Zebrafish were exposed to PBDE from eggs to adults. •An increase in Gonadal-Somatic Index and enhanced gonadal development was enhanced. •Fertilization and hatching successes were reduced, while malformation was increased. •PBDE alters sex differentiation, leading to a male biased F1 population. •Environmental relevant concentrations of PBDE threaten natural fish populations. -- PBDE reduces fertilization and hatching successes, causes malformation and leads to a male biased F1 generation in fish

  19. G-protein-coupled estrogen receptor 1 is involved in brain development during zebrafish (Danio rerio) embryogenesis

    International Nuclear Information System (INIS)

    Highlights: •The Gper expression was detected in the developing brain of zebrafish. •Gper morpholino knockdown induced apoptosis of brain cells. •Gper morpholino knockdown reduced expression in neuron markers. •Zebrafish Gper may be involved in neuronal development. -- Abstract: G-protein-coupled estrogen receptor 1 (Gper, formerly known as GPR30) is found to be a trophic and protective factor in mediating action of estrogen in adult brain, while its role in developing brain remains to be elucidated. Here we present the expression pattern of Gper and its functions during embryogenesis in zebrafish. Both the mRNA and protein of Gper were detected throughout embryogenesis. Whole mount in situ hybridization (WISH) revealed a wide distribution of gper mRNAs in various regions of the developing brain. Gper knockdown by specific morpholinos resulted in growth retardation in embryos and morphological defects in the developing brain. In addition, induced apoptosis, decreased proliferation of the brain cells and maldevelopment of sensory and motor neurons were also found in the morphants. Our results provide novel insights into Gper functions in the developing brain, revealing that Gper can maintain the survival of the brain cells, and formation and/or differentiation of the sensory and motor neurons

  20. G-protein-coupled estrogen receptor 1 is involved in brain development during zebrafish (Danio rerio) embryogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Yanan; Liu, Xiaochun [State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals and Guangdong Provincial Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275 (China); Zhu, Pei; Li, Jianzhen; Sham, Kathy W.Y. [School of Biomedical Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong (China); Cheng, Shuk Han [Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong (China); Li, Shuisheng; Zhang, Yong [State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals and Guangdong Provincial Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275 (China); Cheng, Christopher H.K., E-mail: chkcheng@cuhk.edu.hk [School of Biomedical Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong (China); Lin, Haoran, E-mail: lsslhr@mail.sysu.edu.cn [State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals and Guangdong Provincial Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275 (China); College of Ocean, Hainan University, Haikou 570228, Hainan (China)

    2013-05-24

    Highlights: •The Gper expression was detected in the developing brain of zebrafish. •Gper morpholino knockdown induced apoptosis of brain cells. •Gper morpholino knockdown reduced expression in neuron markers. •Zebrafish Gper may be involved in neuronal development. -- Abstract: G-protein-coupled estrogen receptor 1 (Gper, formerly known as GPR30) is found to be a trophic and protective factor in mediating action of estrogen in adult brain, while its role in developing brain remains to be elucidated. Here we present the expression pattern of Gper and its functions during embryogenesis in zebrafish. Both the mRNA and protein of Gper were detected throughout embryogenesis. Whole mount in situ hybridization (WISH) revealed a wide distribution of gper mRNAs in various regions of the developing brain. Gper knockdown by specific morpholinos resulted in growth retardation in embryos and morphological defects in the developing brain. In addition, induced apoptosis, decreased proliferation of the brain cells and maldevelopment of sensory and motor neurons were also found in the morphants. Our results provide novel insights into Gper functions in the developing brain, revealing that Gper can maintain the survival of the brain cells, and formation and/or differentiation of the sensory and motor neurons.

  1. Effects of acoustic levitation on the development of zebrafish, Danio rerio, embryos.

    Science.gov (United States)

    Sundvik, Maria; Nieminen, Heikki J; Salmi, Ari; Panula, Pertti; Hæggström, Edward

    2015-01-01

    Acoustic levitation provides potential to characterize and manipulate material such as solid particles and fluid in a wall-less environment. While attempts to levitate small animals have been made, the biological effects of such levitation have been scarcely documented. Here, our goal was to explore if zebrafish embryos can be levitated (peak pressures at the pressure node and anti-node: 135 dB and 144 dB, respectively) with no effects on early development. We levitated the embryos (n = 94) at 2-14 hours post fertilization (hpf) for 1000 (n = 47) or 2000 seconds (n = 47). We compared the size and number of trunk neuromasts and otoliths in sonicated samples to controls (n = 94), and found no statistically significant differences (p > 0.05). While mortality rate was lower in the control group (22.3%) compared to that in the 1000 s (34.0%) and 2000 s (42.6%) levitation groups, the differences were statistically insignificant (p > 0.05). The results suggest that acoustic levitation for less than 2000 sec does not interfere with the development of zebrafish embryos, but may affect mortality rate. Acoustic levitation could potentially be used as a non-contacting wall-less platform for characterizing and manipulating vertebrae embryos without causing major adverse effects to their development. PMID:26337364

  2. The Laboratory Breeding Methods of Zebrafish (Danio rerio)%斑马鱼实验室繁育方法研究进展

    Institute of Scientific and Technical Information of China (English)

    邵潘柱; 林金杏; 胡建华

    2013-01-01

    In recent years,because of unique biological characteristics and advantages,zebrafish (Danio rerio) has become a new type of vertebrate model organisms and is beginning to attract the attention of the world scientific researchers.However,there is little information about laboratory breeding and farming methods of zebrafish in our country.A detailed description for the laboratory captivity and breeding of zebrafish was conducted on the basis of the experimental experience,so as to provide basis feeding information for the zebrafish research.%近年来,斑马鱼因其独特的生物学特性及优势已成为一种新型的脊椎动物模式生物,并渐渐引起世界各国科研人员的重视.但目前在我国斑马鱼实验室养殖及繁育等方面的文献、资料并不多见.笔者对斑马鱼实验室人工饲养及繁育等方面做了较为详细的介绍,旨在为斑马鱼这种重要模式生物的研究提供基础的参考资料.

  3. Cyhalofop-butyl has the potential to induce developmental toxicity, oxidative stress and apoptosis in early life stage of zebrafish (Danio rerio)

    International Nuclear Information System (INIS)

    Cyhalofop-butyl is a selective herbicide widely employed in paddy field, which can transfer into aquatic environments. However, details of the environmental risk and aquatic toxicity of cyhalofop-butyl have not been fully investigated. In this study, zebrafish (Danio rerio) embryos were exposed to a range of cyhalofop-butyl until 120 hour post-fertilization (hpf) to assess embryonic toxicity of the chemical. Our results demonstrated that cyhalofop-butyl was highly toxic to zebrafish embryos, with concentration-dependent negative effects in embryonic development. In addition, exposure to cyhalofop-butyl resulted in significant increases in reactive oxygen species (ROS) production and cell apoptosis in heart area. The mRNA levels of the genes related to oxidative stress and apoptosis were also altered significantly after cyhalofop-butyl exposure. Moreover, the activity of capspase-9 and caspase-3 were significantly increased. Therefore, we speculated that oxidative stress-induced apoptosis should be responsible for abnormal development during embryogenesis after cyhalofop-butyl exposure. - Highlights: • Cyhalofop-butyl can induce developmental toxicity in zebrafish embryos. • Cyhalofop-butyl can induce oxidative stress and apoptosis in zebrafish embryos. • Oxidative stress-induced apoptosis might be responsible for abnormal development. - Cyhalofop-butyl could induce negative effects in embryonic development. The cyhalofop-butyl – induced developmental toxicity could be explained by oxidative stress-induced apoptosis

  4. Developmental exposure to progestins causes male bias and precocious puberty in zebrafish (Danio rerio).

    Science.gov (United States)

    Svensson, Johan; Mustafa, Arshi; Fick, Jerker; Schmitz, Monika; Brunström, Björn

    2016-08-01

    Progestins are aquatic contaminants that in low concentrations can impair fish reproduction. The mechanisms are likely multiple since different progestins interact with other steroid receptors in addition to progesterone receptors. Puberty is the process when animals first acquire the capability to reproduce and it comprises maturation of sperm and eggs. In zebrafish, puberty is initiated around 45days post fertilization (dpf) in females and around 53-55 dpf in males, and is marked by increased production of pituitary gonadotropins. We exposed juvenile zebrafish from 20 to 80 dpf to the androgenic progestin levonorgestrel at concentrations of 5.5, 79 and 834ngL(-1) and to the non-androgenic progestin progesterone at concentrations of 3.7, 77 and 1122ngL(-1), during sexual differentiation and puberty. Levonorgestrel exposure caused 100% males even at the lowest concentration tested whereas progesterone did not affect the sex ratio. Transcript levels of the gonadal genes amh, CYP11B and CYP19a1a indicated that the masculinizing effect of levonorgestrel occurred very rapidly. Transcript concentrations of gonadotropins in pituitaries were low in control fish at 44 dpf, but high at 55 dpf and onward. In fish exposed to levonorgestrel or progesterone gonadotropin transcript concentrations were high already at 44 dpf, indicating that both progestins caused precocious puberty. Gonad histology at 50 dpf confirmed a well advanced sexual maturation, but only in males. Our results show that progestins can affect sexual development in fish and that the androgenic progestin levonorgestrel induces a male phenotype at concentrations similar to those detected in aquatic environments. PMID:27348263

  5. Gonadotropin-releasing hormone 2 suppresses food intake in the zebrafish, Danio rerio

    Directory of Open Access Journals (Sweden)

    Ryo eNishiguchi

    2012-10-01

    Full Text Available Gonadotropin-releasing hormone (GnRH is an evolutionarily conserved neuropeptide with 10 amino acid residues, of which several structural variants exist. A molecular form known as GnRH2 ([His5 Trp7 Tyr8]GnRH, also known as chicken GnRH II is widely distributed in vertebrates except for rodents, and has recently been implicated in the regulation of feeding behavior in goldfish. However, the influence of GnRH2 on feeding behavior in other fish has not yet been studied. In the present study, therefore, we investigated the role of GnRH2 in the regulation of feeding behavior in a zebrafish model, and examined its involvement in food intake after intracerebroventricular (ICV administration. ICV injection of GnRH2 at 0.1 and 1 pmol/g body weight (BW induced a marked decrease of food consumption in a dose-dependent manner during 30 min after feeding. Cumulative food intake was significantly decreased by ICV injection of GnRH2 at 1 pmol/g BW during the 30-min post-treatment observation period. The anorexigenic action of GnRH2 was completely blocked by treatment with the GnRH type I receptor antagonist Antide at 50 pmol/g BW. We also examined the effect of feeding condition on the expression level of the GnRH2 transcript in the hypothalamus. Levels of GnRH2 mRNA obtained from fish that had been provided excess food for 7 days were higher than those in fish that had been fed normally. These results suggest that, in zebrafish, GnRH2 acts as an anorexigenic factor, as is the case in goldfish.

  6. Gonadotropin-releasing hormone 2 suppresses food intake in the zebrafish, Danio rerio.

    Science.gov (United States)

    Nishiguchi, Ryo; Azuma, Morio; Yokobori, Eri; Uchiyama, Minoru; Matsuda, Kouhei

    2012-01-01

    Gonadotropin-releasing hormone (GnRH) is an evolutionarily conserved neuropeptide with 10 amino acid residues, of which several structural variants exist. A molecular form known as GnRH2 ([His(5) Trp(7) Tyr(8)]GnRH, also known as chicken GnRH II) is widely distributed in vertebrates except for rodents, and has recently been implicated in the regulation of feeding behavior in goldfish. However, the influence of GnRH2 on feeding behavior in other fish has not yet been studied. In the present study, therefore, we investigated the role of GnRH2 in the regulation of feeding behavior in a zebrafish model, and examined its involvement in food intake after intracerebroventricular (ICV) administration. ICV injection of GnRH2 at 0.1 and 1 pmol/g body weight (BW) induced a marked decrease of food consumption in a dose-dependent manner during 30 min after feeding. Cumulative food intake was significantly decreased by ICV injection of GnRH2 at 1 pmol/g BW during the 30-min post-treatment observation period. The anorexigenic action of GnRH2 was completely blocked by treatment with the GnRH type I receptor antagonist Antide at 25 pmol/g BW. We also examined the effect of feeding condition on the expression level of the GnRH2 transcript in the hypothalamus. Levels of GnRH2 mRNA obtained from fish that had been provided excess food for 7 days were higher than those in fish that had been fed normally. These results suggest that, in zebrafish, GnRH2 acts as an anorexigenic factor, as is the case in goldfish. PMID:23087673

  7. Xenobiotic-induced changes in the arginase activity of zebrafish (Danio rerio) eleutheroembryo.

    Science.gov (United States)

    Fuentealba González, Pablo; Llanos-Rivera, Alejandra; Carvajal Baeza, Nelson; Uribe Pérez, Elena

    2011-10-01

    The impact of xenobiotics in organisms at the biochemical level can be detected using specific or nonspecific biochemical markers. Activity of the enzyme arginase is used as a biochemical parameter of cell proliferation in mammals because of its importance in polyamine synthesis, which provides molecules for cellular growth and differentiation. Therefore, total arginase activity could indicate sublethal organism alterations induced by xenobiotics. In the present study, bioassays with early stages of Danio rerio were implemented using the pesticide malathion as a reference toxicant and a kraft pulp mill (KPM) effluent to assess their potential toxicity. The experimental design considered a 144-h static bioassay that involved incubation from an early 3-h postfertilization embryonic stage through to the eleutheroembryo stage. Growth variations and observations of organ development were evaluated and related to total arginase activity. The enzymatic activity in eleutheroembryo exposed to malathion exhibited a significant decrease at concentrations equal to or higher than 3 mg/L. Delays in the early development and morphometric parameters suggest metabolic depression in these conditions. A significant positive relationship between total arginase activity and eleutheroembryo development was observed, indicating that a decrease in total arginase activity might be related to sublethal alterations in eleutheroembryo growth. Bioassay results with KPM effluents resulted in a delay in organogenesis only in effluent concentrations of 100% and were related to a significant decrease in total arginase activity. In conclusion, total arginase activity has a higher sensitivity compared with morphological parameters in providing an early signal of the sublethal effects on early life stages of fish exposed to environmental stress. PMID:21766322

  8. ESX-5-deficient Mycobacterium marinum is hypervirulent in adult zebrafish

    KAUST Repository

    Weerdenburg, Eveline M.

    2012-02-15

    ESX-5 is a mycobacterial type VII protein secretion system responsible for transport of numerous PE and PPE proteins. It is involved in the induction of host cell death and modulation of the cytokine response in vitro. In this work, we studied the effects of ESX-5 in embryonic and adult zebrafish using Mycobacterium marinum. We found that ESX-5-deficient M.marinum was slightly attenuated in zebrafish embryos. Surprisingly, the same mutant showed highly increased virulence in adult zebrafish, characterized by increased bacterial loads and early onset of granuloma formation with rapid development of necrotic centres. This early onset of granuloma formation was accompanied by an increased expression of pro-inflammatory cytokines and tissue remodelling genes in zebrafish infected with the ESX-5 mutant. Experiments using RAG-1-deficient zebrafish showed that the increased virulence of the ESX-5 mutant was not dependent on the adaptive immune system. Mixed infection experiments with wild-type and ESX-5 mutant bacteria showed that the latter had a specific advantage in adult zebrafish and outcompeted wild-type bacteria. Together our experiments indicate that ESX-5-mediated protein secretion is used by M.marinum to establish a moderate and persistent infection. © 2012 Blackwell Publishing Ltd.

  9. Revealing genes associated with vitellogenesis in the liver of the zebrafish (Danio rerio by transcriptome profiling

    Directory of Open Access Journals (Sweden)

    Hyslop Terry

    2009-03-01

    Full Text Available Abstract Background In oviparous vertebrates, including fish, vitellogenesis consists of highly regulated pathways involving 17β-estradiol (E2. Previous studies focused on a relatively small number of hepatic expressed genes during vitellogenesis. This study aims to identify hepatic genes involved in vitellogenesis and regulated by E2, by using zebrafish microarray gene expression profiling, and to provide information on functional distinctive genes expressed in the liver of a vitellogenic female, using zebrafish as a model fish. Results Genes associated with vitellogenesis were revealed by the following paired t-tests (SAM comparisons: a two-month old vitellogenic (Vit2 females were compared with non-vitellogenic (NV females, showing 825 differentially expressed transcripts during early stages of vitellogenesis, b four-month old vitellogenic (Vit4 females were compared with NV females, showing 1,046 differentially expressed transcripts during vitellogenesis and c E2-treated males were compared with control males, showing 1,828 differentially expressed transcripts regulated by E2. A Venn diagram revealed 822 common transcripts in the three groups, indicating that these transcripts were involved in vitellogenesis and putatively regulated by E2. In addition, 431 transcripts were differentially expressed in Vit2 and Vit4 females but not in E2-treated males, indicating that they were putatively not up-regulated by E2. Correspondence analysis showed high similarity in expression profiles of Vit2 with Vit4 and of NV females with control males. The E2-treated males differed from the other groups. The repertoire of genes putatively regulated by E2 in vitellogenic females included genes associated with protein synthesis and reproduction. Genes associated with the immune system processes and biological adhesion, were among the genes that were putatively not regulated by E2. E2-treated males expressed a large array of transcripts that were not associated

  10. Viability of zebrafish (Danio rerio) ovarian follicles after vitrification in a metal container.

    Science.gov (United States)

    Marques, Lis S; Bos-Mikich, Adriana; Godoy, Leandro C; Silva, Laura A; Maschio, Daniel; Zhang, Tiantian; Streit, Danilo P

    2015-12-01

    Cryopreservation of ovarian tissue has been studied for female germline preservation of farm animals and endangered mammalian species. However, there are relatively few reports on cryopreservation of fish ovarian tissue and especially using vitrification approach. Previous studies of our group has shown that the use of a metal container for the cryopreservation of bovine ovarian fragments results in good primordial and primary follicle morphological integrity after vitrification. The aim of this study was to assess the viability and in vitro development of zebrafish follicles after vitrification of fragmented or whole ovaries using the same metal container. In Experiment 1, we tested the follicular viability of five developmental stages following vitrification in four vitrification solutions using fluorescein diacetate and propidium iodide fluorescent probes. These results showed that the highest viability rates were obtained with immature follicles (Stage I) and VS1 (1.5 M methanol + 4.5 M propylene glycol). In Experiment 2, we used VS1 to vitrify different types of ovarian tissue (fragments or whole ovaries) in two different carriers (plastic cryotube or metal container). In this experiment, Stage I follicle survival was assessed following vitrification by vital staining after 24 h in vitro culture. Follicular morphology was analyzed by light microscopy after vitrification. Data showed that the immature follicles morphology was well preserved after cryopreservation. Follicular survival rate was higher (P < 0.05) in vitrified fragments, when compared to whole ovaries. There were no significant differences in follicular survival and growth when the two vitrification devices were compared.

  11. Developmental Toxicity of Diclofenac and Elucidation of Gene Regulation in zebrafish (Danio rerio)

    Science.gov (United States)

    Chen, Jia-Bin; Gao, Hong-Wen; Zhang, Ya-Lei; Zhang, Yong; Zhou, Xue-Fei; Li, Chun-Qi; Gao, Hai-Ping

    2014-05-01

    Environmental pollution by emerging contaminants, e.g. pharmaceuticals, has become a matter of widespread concern in recent years. We investigated the membrane transport of diclofenac and its toxic effects on gene expression and the development of zebrafish embryos. The association of diclofenac with the embryos conformed to the general partition model at low concentration, the partition coefficient being 0.0033 ml per embryo. At high concentration, the interaction fitted the Freundlich model. Most of the diclofenac remained in the extracellular aqueous solution with less than 5% interacting with the embryo, about half of which was adsorbed on the membranes while the rest entered the cytoplasm. Concentrations of diclofenac over 10.13 μM were lethal to all the embryos, while 3.78 μM diclofenac was teratogenic. The development abnormalities at 4 day post treatment (dpt) include shorter body length, smaller eye, pericardial and body edema, lack of liver, intestine and circulation, muscle degeneration, and abnormal pigmentation. The portion of the diclofenac transferred into the embryo altered the expression of certain genes, e.g. down-regulation of Wnt3a and Gata4 and up-regulation of Wnt8a. The alteration of expression of such genes or the regulation of downstream genes could cause defects in the cardiovascular and nervous systems.

  12. The dynamics of neutrophils in zebrafish (Danio rerio) during infection with the parasite Ichthyophthirius multifiliis.

    Science.gov (United States)

    von Gersdorff Jørgensen, Louise

    2016-08-01

    Ichthyophthirius multifiliis is a ciliated protozoan parasite infecting the skin and gills of freshwater fish. Neutrophils are attracted to the infection sites, as a part of the innate immune response. In this study a transgenic line of zebrafish (Tg(MPO:GFP)(i114)) with GFP-tagged neutrophils was infected with I. multifiliis and the neutrophil influx in the caudal fin was quantified. Twenty-four hours post infection (pi) the neutrophil count had gone up with an average of 3.4 fold. Forty-eight h pi the neutrophil count had dropped 12% and 72 h pi it had dropped to 21% compared to 24 h pi. At 72 h pi the neutrophil count was 2.7 times higher than prior to infection. A few dead parasites were observed, which were disintegrated and covered internally and externally with neutrophils. Live parasites, both surrounded by neutrophils and with no neutrophils in the near vicinity, were found during the infection. Neutrophils interacted directly with the parasites with pseudopod formation projecting towards the pathogen. These results indicate a strong innate immune response immediately following infection and/or a subsequent immune evasion by the parasite. PMID:27231191

  13. Expression of nitric oxide synthase in the developing eye of Zebrafish Danio rerio

    Institute of Scientific and Technical Information of China (English)

    WANG Yongjun; ZHANG Shicui; M S. Sawant

    2004-01-01

    Expression of nitric oxide synthase (NOS) in the developing eye of zebrafish was studied by NADPH-diaphorase staining technique. NOS activity was first observed in the optic primordium and the lens placode at 5-somite stage, and remained basically unchanged up to the prim-5 stage. Upon hatching, NOS activity was nearly equally detected in the gangalion cell layer and the photoreceptor layer in the developing retina. However, it began declining in the inner plexiform layer and the inner nuclear layer at this stage. NOS activity disappeared in the lens although the anterior lens epithelium was strongly stained. Two days after hatching, NOS activity was still strong in the photoreceptor layer, but decreased markedly in the gangalion cell layer, the inner plexiform layer and the inner nuclear layer with the retinal patterning. These suggested that nitric oxide (NO), the product of NOS, is not only involved in the modulation of patterning and differentiation of the retinal cells but also in the regulation of proliferation, and differentiation of the lens fibrocytes.

  14. Co-Expression of Neighboring Genes in the Zebrafish (Danio rerio Genome

    Directory of Open Access Journals (Sweden)

    Daryi Wang

    2009-08-01

    Full Text Available Neighboring genes in the eukaryotic genome have a tendency to express concurrently, and the proximity of two adjacent genes is often considered a possible explanation for their co-expression behavior. However, the actual contribution of the physical distance between two genes to their co-expression behavior has yet to be defined. To further investigate this issue, we studied the co-expression of neighboring genes in zebrafish, which has a compact genome and has experienced a whole genome duplication event. Our analysis shows that the proportion of highly co-expressed neighboring pairs (Pearson’s correlation coefficient R>0.7 is low (0.24% ~ 0.67%; however, it is still significantly higher than that of random pairs. In particular, the statistical result implies that the co-expression tendency of neighboring pairs is negatively correlated with their physical distance. Our findings therefore suggest that physical distance may play an important role in the co-expression of neighboring genes. Possible mechanisms related to the neighboring genes’ co-expression are also discussed.

  15. Expression of nitric oxide synthase in the developing eye of Zebrafish Danio rerio

    Science.gov (United States)

    Wang, Yongjun; Zhang, Shicui; Sawant, M. S.

    2004-12-01

    Expression of nitric oxide synthase (NOS) in the developing eye of zebrafish was studied by NADPH-diaphorase staining technique. NOS activity was first observed in the optic primordium and the lens placode at 5-somite stage, and remained basically unchanged up to the prim-5 stage. Upon hatching, NOS activity was nearly equally detected in the gangalion cell layer and the photoreceptor layer in the developing retina. However, it began declining in the inner plexiform layer and the inner nuclear layer at this stage. NOS activity disappeared in the lens although the anterior lens epithelium was strongly stained. Two days after hatching, NOS activity was still strong in the photoreceptor layer, but decreased markedly in the gangalion cell layer, the inner plexiform layer and the inner nuclear layer with the retinal patterning. These suggested that nitric oxide (NO), the product of NOS, is not only involved in the modulation of patterning and differentiation of the retinal cells but also in the regulation of proliferation, and differentiation of the lens fibrocytes.

  16. Pharmacological Modulation of Hemodynamics in Adult Zebrafish In Vivo.

    Directory of Open Access Journals (Sweden)

    Daniel Brönnimann

    Full Text Available Hemodynamic parameters in zebrafish receive increasing attention because of their important role in cardiovascular processes such as atherosclerosis, hematopoiesis, sprouting and intussusceptive angiogenesis. To study underlying mechanisms, the precise modulation of parameters like blood flow velocity or shear stress is centrally important. Questions related to blood flow have been addressed in the past in either embryonic or ex vivo-zebrafish models but little information is available for adult animals. Here we describe a pharmacological approach to modulate cardiac and hemodynamic parameters in adult zebrafish in vivo.Adult zebrafish were paralyzed and orally perfused with salt water. The drugs isoprenaline and sodium nitroprusside were directly applied with the perfusate, thus closely resembling the preferred method for drug delivery in zebrafish, namely within the water. Drug effects on the heart and on blood flow in the submental vein were studied using electrocardiograms, in vivo-microscopy and mathematical flow simulations.Under control conditions, heart rate, blood flow velocity and shear stress varied less than ± 5%. Maximal chronotropic effects of isoprenaline were achieved at a concentration of 50 μmol/L, where it increased the heart rate by 22.6 ± 1.3% (n = 4; p < 0.0001. Blood flow velocity and shear stress in the submental vein were not significantly increased. Sodium nitroprusside at 1 mmol/L did not alter the heart rate but increased blood flow velocity by 110.46 ± 19.64% (p = 0.01 and shear stress by 117.96 ± 23.65% (n = 9; p = 0.03.In this study, we demonstrate that cardiac and hemodynamic parameters in adult zebrafish can be efficiently modulated by isoprenaline and sodium nitroprusside. Together with the suitability of the zebrafish for in vivo-microscopy and genetic modifications, the methodology described permits studying biological processes that are dependent on hemodynamic alterations.

  17. Exploring the effect of exercise on the transcriptome of zebrafish larvae (Danio rerio)

    NARCIS (Netherlands)

    Fiaz, A.W.; Leon, K.M.; Leeuwen, van J.L.; Kranenbarg, S.

    2014-01-01

    In adult vertebrates, endurance training leads to physiological, metabolical and molecular adaptations which improve endurance performance. Only very few studies have focused on adaptive responses to endurance training during early vertebrate development, and molecular data is limited. Here, we expl

  18. Cobalt-induced genotoxicity in male zebrafish (Danio rerio), with implications for reproduction and expression of DNA repair genes

    International Nuclear Information System (INIS)

    Although cobalt (Co) is an environmental contaminant of surface waters in both radioactive (e.g. 60Co) and non-radioactive forms, there is relatively little information about Co toxicity in fishes. The objective of this study was to investigate acute and chronic toxicity of Co in zebrafish, with emphasis on male genotoxicity and implications for reproductive success. The lethal concentration for 50% mortality (LC50) in larval zebrafish exposed (96 h) to 0–50 mg l−1 Co was 35.3 ± 1.1 (95% C.I.) mg l−1 Co. Adult zebrafish were exposed (13 d) to sub-lethal (0–25 mg l−1) Co and allowed to spawn every 4 d and embryos were collected. After 12-d exposure, fertilisation rate was reduced (6% total eggs fertilised, 25 mg l−1) and embryo survival to hatching decreased (60% fertilised eggs survived, 25 mg l−1). A concentration-dependent increase in DNA strand breaks was detected in sperm from males exposed (13 d) to Co, and DNA damage in sperm returned to control levels after males recovered for 6 d in clean water. Induction of DNA repair genes (rad51, xrcc5, and xrcc6) in testes was complex and not directly related to Co concentration, although there was significant induction in fish exposed to 15 and 25 mg l−1 Co relative to controls. Induction of 4.0 ± 0.9, 2.5 ± 0.7, and 3.1 ± 0.7-fold change (mean ± S.E.M. for rad51, xrcc5, and xrcc6, respectively) was observed in testes at the highest Co concentration (25 mg l−1). Expression of these genes was not altered in offspring (larvae) spawned after 12-d exposure. Chronic exposure to Co resulted in DNA damage in sperm, induction of DNA repair genes in testes, and indications of reduced reproductive success.

  19. Cathepsin activities and membrane integrity of zebrafish (Danio rerio) oocytes after freezing to -196 degrees C using controlled slow cooling.

    Science.gov (United States)

    Zhang, T; Rawson, D M; Tosti, L; Carnevali, O

    2008-04-01

    This study investigated enzymatic activity of cathepsins and the membrane integrity of zebrafish (Danio rerio) oocytes after freezing to -196 degrees C using controlled slow cooling. Stage III oocytes (>0.5mm), obtained through dissection of anaesthetised female fish and desegregation of ovarian cumulus, were exposed to 2M methanol or 2M DMSO (both prepared in Hank's medium) for 30min at 22 degrees C before being loaded into 0.5ml plastic straws and placed into a programmable cooler. After controlled slow freezing, samples were plunged into liquid nitrogen (LN) and held for at least 10min, and thawed by immersing straws into a 27 degrees C water bath for 10s. Thawed oocytes were washed twice in Hank's medium. Cathepsin activity and membrane integrity of oocytes were assessed both after cryoprotectant treatment at 22 degrees C and after freezing in LN. Cathepsin B and L colorimetric analyses were performed using substrates Z-Arg-ArgNNap and Z-Phe-Arg-4MbetaNA-HCl, respectively, and 2-naphthylamine and 4-methoxy-2-naphthylamine were used as standards. Cathepsin D activity was performed by analysing the level of hydrolytic action on haemoglobin. Oocytes membrane integrity was assessed using 0.2% Trypan blue staining for 5min. Analysis of cathepsin activities showed that whilst the activity of cathepsin B and D was not affected by 2M DMSO treatment, their activity was lowered when treated with 2M methanol. Following freezing to -196 degrees C, the activity of all cathepsins (B, D and L) was significantly decreased in both 2M DMSO and 2M methanol. Trypan blue staining showed that 63.0+/-11.3% and 72.7+/-5.2% oocytes membrane stayed intact after DMSO and methanol treatment for 30min at 22 degrees C, respectively, whilst 14.9+/-2.6% and 1.4+/-0.8% stayed intact after freezing in DMSO and methanol to -196 degrees C. The results indicate that cryoprotectant treatment and freezing modified the activities of lysosomal enzymes involved in oocyte maturation and yolk

  20. Effects of postprandial starvation on mRNA expression of endocrine-, amino acid and peptide transporter-, and metabolic enzyme-related genes in zebrafish (Danio rerio).

    Science.gov (United States)

    Tian, Juan; He, Gen; Mai, Kangsen; Liu, Chengdong

    2015-06-01

    The goal of this study was to systematically evaluate the molecular activities of endocrine-, amino acid and peptide transporters-, and metabolic enzyme-related genes in 35-day-old mixed-sex zebrafish (Danio rerio) after feeding . Zebrafish with initial body weights ranging from 9 to 11 mg were fasted for 384 h in a controlled indoor environment. Fish were sampled at 0, 3, 6, 12, 24, 48, 96, 192, and 384 h after fed. Overall, the present study results show that the regulatory mechanism that insulin-like growth factor I negative feedback regulated growth hormone is conserved in zebrafish, as it is in mammals, but that regulation of growth hormone receptors is highly intricate. Leptin and cholecystokinin are time-dependent negative feedback signals, and neuropeptide Y may be an important positive neuropeptide for food intake in zebrafish. The amino acid/carnitine transporters B(0,+) (ATB(0,+)) and broad neutral (0) amino acid transporter 1(B(0)AT1) mRNA levels measured in our study suggest that protein may be utilized during 24-96 h of fasting in zebrafish. Glutamine synthetase mRNA levels were downregulated, and glutamate dehydrogenase, alanine aminotransferase, aspartate transaminase, and trypsin mRNA levels were upregulated after longtime fasting in this study. The mRNA expression levels of fatty acid synthetase decreased significantly (P < 0.05), whereas those of lipoprotein lipase rapidly increased after 96 h of fasting. Fasting activated the expression of glucose synthesis genes when fasting for short periods of time; when fasting is prolonged, the mRNA levels of glucose breakdown enzymes and pentose phosphate shunt genes decreased. PMID:25805459

  1. The hazard assessment of nanostructured CeO{sub 2}-based mixed oxides on the zebrafish Danio rerio under environmentally relevant UV-A exposure

    Energy Technology Data Exchange (ETDEWEB)

    Jemec, Anita, E-mail: anita.jemec@bf.uni-lj.si [National Institute of Chemistry, Laboratory for Environmental Sciences and Engineering, Hajdrihova 19, SI-1001 Ljubljana (Slovenia); University of Ljubljana, Biotechnical Faculty, Department of Biology, Večna pot 111, SI-1000 Ljubljana (Slovenia); Djinović, Petar; Črnivec, Ilja Gasan Osojnik; Pintar, Albin [National Institute of Chemistry, Laboratory for Environmental Sciences and Engineering, Hajdrihova 19, SI-1001 Ljubljana (Slovenia)

    2015-02-15

    The effect of nanomaterials on biota under realistic environmental conditions is an important question. However, there is still a lack of knowledge on how different illumination conditions alter the toxicity of some photocatalytic nanomaterials. We have investigated how environmentally relevant UV-A exposure (intensity 8.50 ± 0.61 W/m{sup 2}, exposure dose 9.0 J/cm{sup 2}) affected the toxicity of cerium oxide (CeO{sub 2})-based nanostructured materials to the early-life stages of zebrafish Danio rerio. Pure cerium oxide (CeO{sub 2}), copper–cerium (CuO–CeO{sub 2}) (with a nominal 10, 15 and 20 mol.% CuO content), cerium–zirconium (CeO{sub 2}–ZrO{sub 2}) and nickel and cobalt (Ni–Co) deposited over CeO{sub 2}–ZrO{sub 2} were tested. It was found that under both illumination regimes, none of the tested materials affected the normal development or induced mortality of zebrafish early-life stages up to 100 mg/L. Only in the case of CuO–CeO{sub 2}, the growth of larvae was decreased (96 h LOEC values for CuCe10, CuCe15 and CuCe20 were 50, 50 and 10 mg/L, respectively). To conclude, CeO{sub 2}-based nanostructured materials are not severely toxic to zebrafish and environmentally relevant UV-A exposure does not enhance their toxicity. - Highlights: • CeO{sub 2}–ZrO{sub 2} nanomaterials and pure CeO{sub 2} (up to 100 mg/L) were not harmful to zebrafish. • Only CuO modified CeO{sub 2} affected the growth of zebrafish larvae. • UV-A radiation did not enhance the toxicity of tested nanomaterials.

  2. Monitoring of single-cell responses in the optic tectum of adult zebrafish with dextran-coupled calcium dyes delivered via local electroporation.

    Directory of Open Access Journals (Sweden)

    Vanessa Kassing

    Full Text Available The zebrafish (Danio rerio has become one of the major animal models for in vivo examination of sensory and neuronal computation. Similar to Xenopus tadpoles neural activity in the optic tectum, the major region controlling visually guided behavior, can be examined in zebrafish larvae by optical imaging. Prerequisites of these approaches are usually the transparency of larvae up to a certain age and the use of two-photon microscopy. This principle of fluorescence excitation was necessary to suppress crosstalk between signals from individual neurons, which is a critical issue when using membrane-permeant dyes. This makes the equipment to study neuronal processing costly and limits the approach to the study of larvae. Thus there is lack of knowledge about the properties of neurons in the optic tectum of adult animals. We established a procedure to circumvent these problems, enabling in vivo calcium imaging in the optic tectum of adult zebrafish. Following local application of dextran-coupled dyes single-neuron activity of adult zebrafish can be monitored with conventional widefield microscopy, because dye labeling remains restricted to tens of neurons or less. Among the neurons characterized with our technique we found neurons that were selective for a certain pattern orientation as well as neurons that responded in a direction-selective way to visual motion. These findings are consistent with previous studies and indicate that the functional integrity of neuronal circuits in the optic tectum of adult zebrafish is preserved with our staining technique. Overall, our protocol for in vivo calcium imaging provides a useful approach to monitor visual responses of individual neurons in the optic tectum of adult zebrafish even when only widefield microscopy is available. This approach will help to obtain valuable insight into the principles of visual computation in adult vertebrates and thus complement previous work on developing visual circuits.

  3. A Surgery Protocol for Adult Zebrafish Spinal Cord Injury

    Institute of Scientific and Technical Information of China (English)

    Ping Fang; Jin-Fei Lin; Hong-Chao Pan; Yan-Qin Shen; Melitta Schachner

    2012-01-01

    Adult zebrafish has a remarkable capability to recover from spinal cord injury,providing an excellent model for studying neuroregeneration.Here we list equipment and reagents,and give a detailed protocol for complete transection of the adult zebrafish spinal cord.In this protocol,potential problems and their solutions are described so that the zebrafish spinal cord injury model can be more easily and reproducibly performed.In addition,two assessments are introduced to monitor the success of the surgery and functional recovery:one test to assess free swimming capability and the other test to assess extent of neuroregeneration by in vivo anterograde axonal tracing.In the swimming behavior test,successful complete spinal cord transection is monitored by the inability of zebrafish to swim freely for 1 week after spinal cord injury,followed by the gradual reacquisition of full locomotor ability within 6 weeks after injury.As a morphometric correlate,anterograde axonal tracing allows the investigator to monitor the ability of regenerated axons to cross the lesion site and increasingly extend into the gray and white matter with time after injury,confirming functional recovery.This zebrafish model provides a paradigm for recovery from spinal cord injury,enabling the identification of pathways and components of neuroregeneration.

  4. Effects of {sup 12}C{sup 6+} ion radiation and ferulic acid on the zebrafish (Danio rerio) embryonic oxidative stress response and gene expression

    Energy Technology Data Exchange (ETDEWEB)

    Si, Jing [Department of Heavy Ion Radiation Medicine, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou 730000 (China); Key Laboratory of Heavy Ion Radiation Medicine of Gansu Province, Lanzhou 730000 (China); Zhang, Hong, E-mail: zhangh@impcas.ac.cn [Department of Heavy Ion Radiation Medicine, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou 730000 (China); Key Laboratory of Heavy Ion Radiation Medicine of Gansu Province, Lanzhou 730000 (China); Wang, Zhenhua; Wu, Zhenhua [Department of Heavy Ion Radiation Medicine, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou 730000 (China); Key Laboratory of Heavy Ion Radiation Medicine of Gansu Province, Lanzhou 730000 (China); Lu, Jiang [Key Laboratory of Xinjiang Phytomedicine Resources, College of Pharmacy, Shihezi University, Shihezi 832002 (China); Di, Cuixia; Zhou, Xin [Department of Heavy Ion Radiation Medicine, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou 730000 (China); Key Laboratory of Heavy Ion Radiation Medicine of Gansu Province, Lanzhou 730000 (China); Wang, Xiaowei [Key Laboratory of Xinjiang Phytomedicine Resources, College of Pharmacy, Shihezi University, Shihezi 832002 (China)

    2013-05-15

    Highlights: • Carbon ion radiation increased the oxidative stress in zebrafish embryos. • Carbon ion radiation induced transcriptional level effects. • The transcriptional level displayed more sensitivity to low dose radiation than the antioxidant enzyme activities. • FA induced radioprotective effects by the inhibition of oxidative stress. - Abstract: The effects of carbon ion irradiation and ferulic acid (FA) on the induction of oxidative stress and alteration of gene expression were studied in zebrafish (Danio rerio) embryos. Zebrafish embryos at 8 hpf were divided into seven groups: the control group; the 1 Gy, 3 Gy and 7 Gy irradiation groups; and three FA-pre-treated irradiation groups. In the irradiated groups, a significant increase in the teratogenesis of the zebrafish embryos and oxidative stress was accompanied by increased malondialdehyde (MDA) content, decreased glutathione (GSH) content and alterations in antioxidant enzyme activities (such as catalase [CAT] and superoxide dismutase [SOD]). Moreover, the mRNA levels for Cu/Zn–sod, Mn–sod, cat and gpx, the genes encoding these antioxidant proteins, were altered significantly. However, the mRNA expression patterns were not in accordance with those of the antioxidant enzymes and were more sensitive under low-dose irradiation. In addition, we detected the mRNA expression of ucp-2 and bcl-2, which are located at the mitochondrial inner membrane and related to reactive oxidative species (ROS) production. In the irradiated groups, the mRNA level of ucp-2 was significantly increased, whereas the mRNA level of bcl-2 was significantly decreased. Supplementation with FA, an antioxidant, was better able to reduce the irradiation-induced oxidative damage marked by changes in mortality, morphology, antioxidant enzyme activities and the MDA and GSH content, as well as in the mRNA expression levels. Overall, this study provided helpful information about the transcriptional effects of irradiation to better

  5. Cobalt-induced genotoxicity in male zebrafish (Danio rerio), with implications for reproduction and expression of DNA repair genes

    Energy Technology Data Exchange (ETDEWEB)

    Reinardy, Helena C.; Syrett, James R. [School of Biomedical and Biological Sciences, University of Plymouth (United Kingdom); Jeffree, Ross A. [Faculty of Science, University of Technology, Sydney, PO Box 123, Broadway, NSW 2007 (Australia); Henry, Theodore B., E-mail: ted.henry@plymouth.ac.uk [School of Biomedical and Biological Sciences, University of Plymouth (United Kingdom); Center for Environmental Biotechnology, University of Tennessee, Knoxville, TN 37996 (United States); Department of Forestry, Wildlife and Fisheries, University of Tennessee, Knoxville, TN 37996. USA (United States); Jha, Awadhesh N. [School of Biomedical and Biological Sciences, The University of Plymouth (United Kingdom)

    2013-01-15

    Although cobalt (Co) is an environmental contaminant of surface waters in both radioactive (e.g. {sup 60}Co) and non-radioactive forms, there is relatively little information about Co toxicity in fishes. The objective of this study was to investigate acute and chronic toxicity of Co in zebrafish, with emphasis on male genotoxicity and implications for reproductive success. The lethal concentration for 50% mortality (LC{sub 50}) in larval zebrafish exposed (96 h) to 0-50 mg l{sup -1} Co was 35.3 {+-} 1.1 (95% C.I.) mg l{sup -1} Co. Adult zebrafish were exposed (13 d) to sub-lethal (0-25 mg l{sup -1}) Co and allowed to spawn every 4 d and embryos were collected. After 12-d exposure, fertilisation rate was reduced (6% total eggs fertilised, 25 mg l{sup -1}) and embryo survival to hatching decreased (60% fertilised eggs survived, 25 mg l{sup -1}). A concentration-dependent increase in DNA strand breaks was detected in sperm from males exposed (13 d) to Co, and DNA damage in sperm returned to control levels after males recovered for 6 d in clean water. Induction of DNA repair genes (rad51, xrcc5, and xrcc6) in testes was complex and not directly related to Co concentration, although there was significant induction in fish exposed to 15 and 25 mg l{sup -1} Co relative to controls. Induction of 4.0 {+-} 0.9, 2.5 {+-} 0.7, and 3.1 {+-} 0.7-fold change (mean {+-} S.E.M. for rad51, xrcc5, and xrcc6, respectively) was observed in testes at the highest Co concentration (25 mg l{sup -1}). Expression of these genes was not altered in offspring (larvae) spawned after 12-d exposure. Chronic exposure to Co resulted in DNA damage in sperm, induction of DNA repair genes in testes, and indications of reduced reproductive success.

  6. Reduced swim performance and aerobic capacity in adult zebrafish exposed to waterborne selenite.

    Science.gov (United States)

    Massé, Anita J; Thomas, Jith K; Janz, David M

    2013-04-01

    Although dietary exposure of adult fish to organoselenium in contaminated aquatic ecosystems has been reported to bioaccumulate and cause larval deformities in offspring, subtle physiological effects produced through low level waterborne selenium exposure in fish such as swim performance and aerobic capacity have not been investigated. To evaluate potential effects of selenite on these responses, adult zebrafish (Danio rerio) were exposed to nominal aqueous concentrations of 0, 10 or 100 μg/L sodium selenite for 14 days. Upon completion of the exposure period, fish underwent two successive swim trials in a swim tunnel respirometer to determine critical swim speed (Ucrit), oxygen consumption (MO2), standard and active metabolic rates, aerobic scope (AS) and cost of transport (COT) followed by analysis of whole body triglyceride and glycogen concentrations. Selenite exposure had a significant negative effect on Ucrit and aerobic capacity. Active metabolic rates and AS significantly decreased in both selenite exposure groups after the second swim trial. No significant effect was observed in MO2, standard metabolic rate, COT, triglyceride and glycogen levels, or condition factor between groups. These results suggest that aqueous selenite exposure at environmentally relevant concentrations produces adverse effects on aerobic capacity that can diminish endurance and maximum swim speeds, which may lower fish survivability.

  7. Cortisol regulates sodium homeostasis by stimulating the transcription of sodium-chloride transporter (NCC) in zebrafish (Danio rerio).

    Science.gov (United States)

    Lin, Chia-Hao; Hu, Huei-Jyun; Hwang, Pung-Pung

    2016-02-15

    In mammals, sodium/hydrogen exchanger (NHE) and sodium-chloride cotransporter (NCC) are expressed in renal tubules, and exhibit functional redundancy and mutual compensation in Na(+) uptake. In teleosts, the gills of the adult and skin of the embryonic stage function as external kidneys, and ionocytes are responsible for ionoregulation in these tissues. NHE- and NCC-expressing ionocytes mutually cooperate to adjust Na(+) uptake, which is analogous to the activity of the mammalian kidney. Cortisol is a hormone that controls Na(+) uptake through regulating NCC expression and activity in mammals; however, cortisol-mediated control of NCC expression is little understood in non-mammalian vertebrates, such as teleosts. It is essential for our understanding of the evolution of such regulation to determine whether cortisol has a conserved effect on NCC in vertebrates. In the present study, we treated zebrafish embryos with low Na(+) medium (LNa, 0.04 mM Na(+)) for 3 d to stimulate the mRNA expression of nhe3b, ncc, and cyp11b1 (a cortisol-synthesis enzyme) and whole body cortisol level. Exogenous cortisol treatment (20 mg/l, 3 d) resulted in an elevation of whole-body Na(+) content, ncc expression, and the density of ncc-expressing cells in zebrafish larvae. In loss-of-function experiments, microinjection of glucocorticoid receptor (gr) morpholino (MO) suppressed sodium content, ncc expression, and the density of ncc-expressing cells, but injection of mr MO had no such effects. In addition, exogenous cortisol treatment and gr MO injection also altered ncc expression and the density of ncc-expressing cells in gcm2 morphant larvae. Taken together, cortisol and GR appear to regulate Na(+) absorption through stimulating ncc expression and the differentiation of ncc-expressing ionocytes, providing new insights into the actions of cortisol on Na(+) uptake.

  8. Stable multilineage xenogeneic replacement of definitive hematopoiesis in adult zebrafish

    Science.gov (United States)

    Hess, Isabell; Boehm, Thomas

    2016-01-01

    Bony fishes are the most numerous and phenotypically diverse group of vertebrates inhabiting our planet, making them an ideal target for identifying general principles of tissue development and function. However, lack of suitable experimental platforms prevents the exploitation of this rich source of natural phenotypic variation. Here, we use a zebrafish strain lacking definitive hematopoiesis for interspecific analysis of hematopoietic cell development. Without conditioning prior to transplantation, hematopoietic progenitor cells from goldfish stably engraft in adult zebrafish homozygous for the c-mybI181N mutation. However, in competitive repopulation experiments, zebrafish hematopoietic cells exhibit an advantage over their goldfish counterparts, possibly owing to subtle species-specific functional differences in hematopoietic microenvironments resulting from over 100 million years of independent evolution. Thus, our unique animal model provides an unprecedented opportunity to genetically and functionally disentangle universal and species-specific contributions of the microenvironment to hematopoietic progenitor cell maintenance and development. PMID:26777855

  9. Subdivisions of the adult zebrafish pallium based on molecular marker analysis [v1; ref status: indexed, http://f1000r.es/4m2

    Directory of Open Access Journals (Sweden)

    Julia Ganz

    2014-12-01

    Full Text Available Background: The telencephalon shows a remarkable structural diversity among vertebrates. In particular, the everted telencephalon of ray-finned fishes has a markedly different morphology compared to the evaginated telencephalon of all other vertebrates. This difference in development has hampered the comparison between different areas of the pallium of ray-finned fishes and the pallial nuclei of all other vertebrates. Various models of homology between pallial subdivisions in ray-finned fishes and the pallial nuclei in tetrapods have been proposed based on connectional, neurochemical, gene expression and functional data. However, no consensus has been reached so far. In recent years, the analysis of conserved developmental marker genes has assisted the identification of homologies for different parts of the telencephalon among several tetrapod species. Results: We have investigated the gene expression pattern of conserved marker genes in the adult zebrafish (Danio rerio pallium to identify pallial subdivisions and their homology to pallial nuclei in tetrapods. Combinatorial expression analysis of ascl1a, eomesa, emx1, emx2, emx3, and Prox1 identifies four main divisions in the adult zebrafish pallium. Within these subdivisions, we propose that Dm is homologous to the pallial amygdala in tetrapods and that the dorsal subdivision of Dl is homologous to part of the hippocampal formation in mouse. We have complemented this analysis be examining the gene expression of emx1, emx2 and emx3 in the zebrafish larval brain. Conclusions: Based on our gene expression data, we propose a new model of subdivisions in the adult zebrafish pallium and their putative homologies to pallial nuclei in tetrapods. Pallial nuclei control sensory, motor, and cognitive functions, like memory, learning and emotion. The identification of pallial subdivisions in the adult zebrafish and their homologies to pallial nuclei in tetrapods will contribute to the use of the zebrafish

  10. Investigation of the Effects of Perfluorooctanoic Acid (PFOA and Perfluorooctane Sulfonate (PFOS on Apoptosis and Cell Cycle in a Zebrafish (Danio rerio Liver Cell Line

    Directory of Open Access Journals (Sweden)

    Yuan Cui

    2015-12-01

    Full Text Available This study aimed to explore the effects of perfluorooctanoic acid (PFOA and perfluorooctane sulfonate (PFOS on apoptosis and cell cycle in a zebrafish (Danio rerio liver cell line (ZFL. Treatment groups included a control group, PFOA-IC50, PFOA-IC80, PFOS-IC50 and PFOS-IC80 groups. IC50 and IC80 concentrations were identified by cellular modeling and MTT assays. mRNA levels of p53, Bcl-2, Bax, Caspase-3 and NF-κB p65 were detected by qPCR. Cell apoptosis and cell cycle were detected by flow cytometry and the protein levels of p53, Bcl-2, Bax, Caspase-3 and NF-κB p65 were determined by western blotting. Both PFOA and PFOS inhibited the growth of zebrafish liver cells, and the inhibition rate of PFOS was higher than that of PFOA. Bcl-2 expression levels in the four groups were significantly higher than the control group and Bcl-2 increased significantly in the PFOA-IC80 group. However, the expression levels of Bax in the four treatment groups were higher than the control group. The percentage of cell apoptosis increased significantly with the treatment of PFOA and PFOS (p < 0.05. Cell cycle and cell proliferation were blocked in both the PFOA-IC80 and PFOS-IC80 groups, indicating that PFOA-IC80 and PFOS-IC50 enhanced apoptosis in ZFL cells.

  11. Effects of decreased muscle activity on developing axial musculature in nic b107 mutant zebrafish (Danio rerio)

    NARCIS (Netherlands)

    Meulen, van der T.; Schipper, H.; Leeuwen, van J.L.; Kranenbarg, S.

    2005-01-01

    The present paper discusses the effects of decreased muscle activity (DMA) on embryonic development in the zebrafish. Wild-type zebrafish embryos become mobile around 18 h post-fertilisation, long before the axial musculature is fully differentiated. As a model for DMA, the nicb107 mutant was used.

  12. Lipidomics and H218O labeling techniques reveal increased remodeling of DHA-containing membrane phospholipids associated with abnormal locomotor responses in α-tocopherol deficient zebrafish (danio rerio) embryos

    Science.gov (United States)

    McDougall, Melissa Q.; Choi, Jaewoo; Stevens, Jan F.; Truong, Lisa; Tanguay, Robert L.; Traber, Maret G.

    2016-01-01

    We hypothesized that vitamin E (α-tocopherol) is required by the developing embryonic brain to prevent depletion of highly polyunsaturated fatty acids, especially docosahexaenoic acid (DHA, 22:6), the loss of which we predicted would underlie abnormal morphological and behavioral outcomes. Therefore, we fed adult 5D zebrafish (Danio rerio) defined diets without (E−) or with added α-tocopherol (E+, 500 mg RRR-α-tocopheryl acetate/kg diet) for a minimum of 80 days, and then spawned them to obtain E− and E+ embryos. The E− compared with E+ embryos were 82% less responsive (p<0.01) to a light/dark stimulus at 96 h post-fertilization (hpf), demonstrating impaired locomotor behavior, even in the absence of gross morphological defects. Evaluation of phospholipid (PL) and lysophospholipid (lyso-PL) composition using untargeted lipidomics in E− compared with E+ embryos at 24, 48, 72, and 120 hpf showed that four PLs and three lyso-PLs containing docosahexaenoic acid (DHA), including lysophosphatidylcholine (LPC 22:6, required for transport of DHA into the brain, p<0.001), were at lower concentrations in E− at all time-points. Additionally, H218O labeling experiments revealed enhanced turnover of LPC 22:6 (p<0.001) and three other DHA-containing PLs in the E− compared with the E+ embryos, suggesting that increased membrane remodeling is a result of PL depletion. Together, these data indicate that α-tocopherol deficiency in the zebrafish embryo causes the specific depletion and increased turnover of DHA-containing PL and lyso-PLs, which may compromise DHA delivery to the brain and thereby contribute to the functional impairments observed in E− embryos. PMID:26774753

  13. Lipidomics and H218O labeling techniques reveal increased remodeling of DHA-containing membrane phospholipids associated with abnormal locomotor responses in α-tocopherol deficient zebrafish (danio rerio embryos

    Directory of Open Access Journals (Sweden)

    Melissa Q. McDougall

    2016-08-01

    Full Text Available We hypothesized that vitamin E (α-tocopherol is required by the developing embryonic brain to prevent depletion of highly polyunsaturated fatty acids, especially docosahexaenoic acid (DHA, 22:6, the loss of which we predicted would underlie abnormal morphological and behavioral outcomes. Therefore, we fed adult 5D zebrafish (Danio rerio defined diets without (E− or with added α-tocopherol (E+, 500 mg RRR-α-tocopheryl acetate/kg diet for a minimum of 80 days, and then spawned them to obtain E− and E+ embryos. The E− compared with E+ embryos were 82% less responsive (p<0.01 to a light/dark stimulus at 96 h post-fertilization (hpf, demonstrating impaired locomotor behavior, even in the absence of gross morphological defects. Evaluation of phospholipid (PL and lysophospholipid (lyso-PL composition using untargeted lipidomics in E− compared with E+ embryos at 24, 48, 72, and 120 hpf showed that four PLs and three lyso-PLs containing docosahexaenoic acid (DHA, including lysophosphatidylcholine (LPC 22:6, required for transport of DHA into the brain, p<0.001, were at lower concentrations in E− at all time-points. Additionally, H218O labeling experiments revealed enhanced turnover of LPC 22:6 (p<0.001 and three other DHA-containing PLs in the E− compared with the E+ embryos, suggesting that increased membrane remodeling is a result of PL depletion. Together, these data indicate that α-tocopherol deficiency in the zebrafish embryo causes the specific depletion and increased turnover of DHA-containing PL and lyso-PLs, which may compromise DHA delivery to the brain and thereby contribute to the functional impairments observed in E− embryos.

  14. Lipidomics and H2(18)O labeling techniques reveal increased remodeling of DHA-containing membrane phospholipids associated with abnormal locomotor responses in α-tocopherol deficient zebrafish (danio rerio) embryos.

    Science.gov (United States)

    McDougall, Melissa Q; Choi, Jaewoo; Stevens, Jan F; Truong, Lisa; Tanguay, Robert L; Traber, Maret G

    2016-08-01

    We hypothesized that vitamin E (α-tocopherol) is required by the developing embryonic brain to prevent depletion of highly polyunsaturated fatty acids, especially docosahexaenoic acid (DHA, 22:6), the loss of which we predicted would underlie abnormal morphological and behavioral outcomes. Therefore, we fed adult 5D zebrafish (Danio rerio) defined diets without (E-) or with added α-tocopherol (E+, 500mg RRR-α-tocopheryl acetate/kg diet) for a minimum of 80 days, and then spawned them to obtain E- and E+ embryos. The E- compared with E+ embryos were 82% less responsive (p<0.01) to a light/dark stimulus at 96h post-fertilization (hpf), demonstrating impaired locomotor behavior, even in the absence of gross morphological defects. Evaluation of phospholipid (PL) and lysophospholipid (lyso-PL) composition using untargeted lipidomics in E- compared with E+ embryos at 24, 48, 72, and 120hpf showed that four PLs and three lyso-PLs containing docosahexaenoic acid (DHA), including lysophosphatidylcholine (LPC 22:6, required for transport of DHA into the brain, p<0.001), were at lower concentrations in E- at all time-points. Additionally, H2(18)O labeling experiments revealed enhanced turnover of LPC 22:6 (p<0.001) and three other DHA-containing PLs in the E- compared with the E+ embryos, suggesting that increased membrane remodeling is a result of PL depletion. Together, these data indicate that α-tocopherol deficiency in the zebrafish embryo causes the specific depletion and increased turnover of DHA-containing PL and lyso-PLs, which may compromise DHA delivery to the brain and thereby contribute to the functional impairments observed in E- embryos. PMID:26774753

  15. Long-term effects of bisphenol AF (BPAF) on hormonal balance and genes of hypothalamus-pituitary-gonad axis and liver of zebrafish (Danio rerio), and the impact on offspring.

    Science.gov (United States)

    Shi, Jiachen; Jiao, Zhihao; Zheng, Sai; Li, Ming; Zhang, Jing; Feng, Yixing; Yin, Jie; Shao, Bing

    2015-06-01

    Bisphenol AF (BPAF) is one of the analogues of bisphenol A (BPA) and is widely used as a raw material in the plastics industry. The potential toxicity to fish from exposure to BPAF in the aquatic environment is largely unknown. In this study, zebrafish (Danio rerio) were exposed to BPAF at 5, 25 and 125 μg L(-1), from 4 hour-post-fertilization (hpf) to 120 day-post-fertilization (dpf), representing the period from embryo to adult. The levels of plasma hormones were measured and the expression of selected representative genes along the hypothalamus-pituitary-gonad (HPG) axis and liver were examined. The concentration of 17β-estradiol (E2) was significantly increased in male and female fish and a significant decrease of testosterone (T) was observed in male fish. The mRNA expression of genes along the HPG axis and in liver tissues in F0 generation fish demonstrated that the steroid hormonal balances of zebrafish were modulated through the alteration of steroidgenesis. The significant decrease of egg fertilization among offspring indicates the possibility of sperm deterioration of parent following exposure to BPAF. The higher occurrence of malformation and lower survival rate in the offspring from the exposure group suggested a possibility of maternal transfer of BPAF, which could be responsible for the increased prevalence of adverse health signs in the offspring. The hatching delay in 5 μg L(-1) BPAF indicated that parental exposure to environmentally relevant concentration of BPAF would result in delayed hatching of the offspring. A potential consequence of adverse effects in the offspring by BPAF deserves further investigation. PMID:25723718

  16. Adaptive changes of Zebrafish (Danio rerio) to anaerobic exercise training%斑马鱼对无氧运动训练的适应性变化

    Institute of Scientific and Technical Information of China (English)

    刘明镜; 王志坚

    2013-01-01

    To explore adaptive changes of the Zebrafish (Danio rerio) to anaerobic exercise training as well as to collect basic data of molecular mechanisms of adaption to anaerobic exercise training among this fish,we investigated the influences of 4 weeks of anaerobic exercise training on the behavior,morphology,growth,muscle biochemical components and metabolic enzyme activities of the Zebrafish.Our results indicated that individual's daily activity level declined after 4 weeks training and they preferred to swim together more frequently.Both body length and weight gain decreased,allowing the fish to adapt to the increased locomotion.Similarly,glycogen in muscles increased and exercise endurance also strengthened due to the enhancement of energy storage.Moreover,although the activity of lactate dehydrogenase (LDH) in muscle has increased,the activity of citrate synthase (CS) decreased.Taken together,these results suggest that both the ability of anaerobic exercise and anaerobic metabolism of Zebrafish can in fact be enhanced by training,and the tangible changes that we could measure were retained,but only for a limited time.%该研究以斑马鱼为(Danio rerio)对象,研究了四周无氧运动训练对斑马鱼行为、形态、生长、肌肉生化组分及代谢酶活性的影响.旨在探索斑马鱼对无氧运动训练的适应性变化,为进一步了解鱼类适应无氧运动训练的分子机制提供基础数据.结果发现:斑马鱼的日常活跃程度经四周无氧运动训练后显著降低,群聚程度增加;训练组个体体重和体长增长减缓,更利于运动;肌糖原含量显著增加,运动持久能力加强;肌肉乳酸脱氢酶(LDH)活性显著增高,柠檬酸合成酶(CS)活性显著降低,无氧代谢能力加强.即,斑马鱼无氧运动能力和无氧代谢能力在训练后得以明显提升.

  17. A comparative expression analysis of gene transcripts in brain tissue of non-transgenic and GH-transgenic zebrafish (Danio rerio using a DDRT-PCR approach

    Directory of Open Access Journals (Sweden)

    Fernanda A. Alves-Costa

    2012-06-01

    Full Text Available The presence of higher level of exogenous growth hormone (GH in transgenic animals could lead to several physiological alterations. A GH transgenic zebrafish (Danio rerio line was compared to nontransgenic (NT samples of the species through a DDRT-PCR approach, with the goal of identifying candidate differentially expressed transcripts in brain tissues that could be involved in GH overexpression. Densitometric analyses of two selected amplification products, p300 and ADCY2, pointed to a significant lower gene expression in the transgenic zebrafish (104.02 ± 57.71; 224.10 ± 91.73 when compared to NT samples (249.75 ± 30.08; 342.95 ± 65.19. The present data indicate that p300 and ADCY2 are involved in a regulation system for GH when high circulating levels of this hormone are found in zebrafishes.A presença de níveis mais elevados do hormônio de crescimento (GH em animais transgênicos poderia levar a várias alterações fisiológicas. Uma linhagem transgênica de paulistinha (Danio rerio para o GH foi comparada com amostras não transgênicas (NT desta espécie, através de uma abordagem de DDRT-PCR, com o objetivo de identificar transcritos candidatos diferencialmente expressos em tecido cerebral que poderiam estar envolvidos na superexpressão de GH. Análises densitométricas de dois produtos de amplificação selecionados, p300 e ADCY2, apontaram uma expressão gênica significativamente menor nas amostras transgênicas de paulistinha (104.02 ± 57.71; 224.10 ± 91.73, quando comparadas com as amostras NT (249.75 ± 30.08; 342.95±65.19. Os presentes dados indicam que p300 e ADCY2 estão envolvidos em um sistema de regulação do GH, quando altos níveis circulantes desse hormônio são encontrados em paulistinha.

  18. Zebrafish ( Danio rerio) as a model for investigating the safety of GM feed ingredients (soya and maize); performance, stress response and uptake of dietary DNA sequences.

    Science.gov (United States)

    Sissener, Nini H; Johannessen, Lene E; Hevrøy, Ernst M; Wiik-Nielsen, Christer R; Berdal, Knut G; Nordgreen, Andreas; Hemre, Gro-Ingunn

    2010-01-01

    A 20-d zebrafish (Danio rerio) feeding trial, in which a near doubling of fish weight was achieved, was conducted with GM feed ingredients to evaluate feed intake, growth, stress response and uptake of dietary DNA. A partial aim of the study was to assess zebrafish as a model organism in GM safety assessments. Roundup Ready soya (RRS), YieldGard Bt maize (MON810) and their non-modified, maternal, near-isogenic lines were used in a 2 x 2 factorial design. Soya variety and maize variety were the main factors, both with two levels; non-GM and GM. Compared with fish fed non-GM maize, those fed GM maize exhibited significantly better growth, had lower mRNA transcription levels of superoxide dismutase (SOD)-1 and a tendency (non-significant) towards lower transcription of heat shock protein 70 in liver. Sex of the fish and soya variety had significant interaction effects on total RNA yield from the whole liver and transcription of SOD-1, suggesting that some diet component affecting males and females differently was present in different levels in the GM and the non-GM soya used in the present study. Dietary DNA sequences were detected in all of the organs analysed, but not all of the samples. Soya and maize rubisco (non-transgenic, multicopy genes) were most frequently detected, while MON810 transgenic DNA fragments were detected in some samples and RRS fragments were not detected. In conclusion, zebrafish shows promise as a model for this application.

  19. Toxicity assessment of water-accommodated fractions from two different oils using a zebrafish (Danio rerio) embryo-larval bioassay with a multilevel approach.

    Science.gov (United States)

    Perrichon, Prescilla; Le Menach, Karyn; Akcha, Farida; Cachot, Jérôme; Budzinski, Hélène; Bustamante, Paco

    2016-10-15

    Petroleum compounds from chronic discharges and oil spills represent an important source of environmental pollution. To better understand the deleterious effects of these compounds, the toxicity of water-accommodated fractions (WAF) from two different oils (brut Arabian Light and Erika heavy fuel oils) were used in this study. Zebrafish embryos (Danio rerio) were exposed during 96h at three WAF concentrations (1, 10 and 100% for Arabian Light and 10, 50 and 100% for Erika) in order to cover a wide range of polycyclic aromatic hydrocarbon (PAH) concentrations, representative of the levels found after environmental oil spills. Several endpoints were recorded at different levels of biological organization, including lethal endpoints, morphological abnormalities, photomotor behavioral responses, cardiac activity, DNA damage and exposure level measurements (EROD activity, cyp1a and PAH metabolites). Neither morphological nor behavioral or physiological alterations were observed after exposure to Arabian Light fractions. In contrast, the Erika fractions led a high degree of toxicity in early life stages of zebrafish. Despite of defense mechanisms induced by oil, acute toxic effects have been recorded including mortality, delayed hatching, high rates of developmental abnormalities, disrupted locomotor activity and cardiac failures at the highest PAH concentrations (∑TPAHs=257,029±47,231ng·L(-1)). Such differences in toxicity are likely related to the oil composition. The use of developing zebrafish is a good tool to identify wide range of detrimental effects and elucidate their underlying foundations. Our work highlights once more, the cardiotoxic action (and potentially neurotoxic) of petroleum-related PAHs. PMID:27312275

  20. Whole-body multispectral photoacoustic imaging of adult zebrafish

    Science.gov (United States)

    Huang, Na; Guo, Heng; Qi, Weizhi; Zhang, Zhiwei; Rong, Jian; Yuan, Zhen; Ge, Wei; Jiang, Huabei; Xi, Lei

    2016-01-01

    The zebrafish, an ideal vertebrate for studying developmental biology and genetics, is increasingly being used to understand human diseases, due to its high similarity to the human genome and its optical transparency during embryonic stages. Once the zebrafish has fully developed, especially wild-type breeds, conventional optical imaging techniques have difficulty in imaging the internal organs and structures with sufficient resolution and penetration depth. Even with established mutant lines that remain transparent throughout their life cycle, it is still challenging for purely optical imaging modalities to visualize the organs of juvenile and adult zebrafish at a micro-scale spatial resolution. In this work, we developed a non-invasive three-dimensional photoacoustic imaging platform with an optimized illumination pattern and a cylindrical-scanning-based data collection system to image entire zebrafish with micro-scale resolutions of 80 μm and 600 μm in the lateral and axial directions, respectively. In addition, we employed a multispectral strategy that utilized excitation wavelengths from 690 nm to 930 nm to statistically quantify the relative optical absorption spectrum of major organs. PMID:27699119

  1. Dissection of the Adult Zebrafish Kidney

    OpenAIRE

    Gerlach, Gary F.; Schrader, Lauran N.; Wingert, Rebecca A

    2011-01-01

    Researchers working in the burgeoning field of adult stem cell biology seek to understand the signals that regulate the behavior and function of stem cells during normal homeostasis and disease states. The understanding of adult stem cells has broad reaching implications for the future of regenerative medicine1. For example, better knowledge about adult stem cell biology can facilitate the design of therapeutic strategies in which organs are triggered to heal themselves or even the creation o...

  2. Fgf regulates dedifferentiation during skeletal muscle regeneration in adult zebrafish.

    Science.gov (United States)

    Saera-Vila, Alfonso; Kish, Phillip E; Kahana, Alon

    2016-09-01

    Fibroblast growth factors (Fgfs) regulate critical biological processes such as embryonic development, tissue homeostasis, wound healing, and tissue regeneration. In zebrafish, Fgf signaling plays an important role in the regeneration of the spinal cord, liver, heart, fin, and photoreceptors, although its exact mechanism of action is not fully understood. Utilizing an adult zebrafish extraocular muscle (EOM) regeneration model, we demonstrate that blocking Fgf receptor function using either a chemical inhibitor (SU5402) or a dominant-negative transgenic construct (dnFGFR1a:EGFP) impairs muscle regeneration. Adult zebrafish EOMs regenerate through a myocyte dedifferentiation process, which involves a muscle-to-mesenchyme transition and cell cycle reentry by differentiated myocytes. Blocking Fgf signaling reduced cell proliferation and active caspase 3 levels in the regenerating muscle with no detectable levels of apoptosis, supporting the hypothesis that Fgf signaling is involved in the early steps of dedifferentiation. Fgf signaling in regenerating myocytes involves the MAPK/ERK pathway: inhibition of MEK activity with U0126 mimicked the phenotype of the Fgf receptor inhibition on both muscle regeneration and cell proliferation, and activated ERK (p-ERK) was detected in injured muscles by immunofluorescence and western blot. Interestingly, following injury, ERK2 expression is specifically induced and activated by phosphorylation, suggesting a key role in muscle regeneration. We conclude that the critical early steps of myocyte dedifferentiation in EOM regeneration are dependent on Fgf signaling. PMID:27267062

  3. In vivo cell tracking and quantification method in adult zebrafish

    Science.gov (United States)

    Zhang, Li; Alt, Clemens; Li, Pulin; White, Richard M.; Zon, Leonard I.; Wei, Xunbin; Lin, Charles P.

    2012-03-01

    Zebrafish have become a powerful vertebrate model organism for drug discovery, cancer and stem cell research. A recently developed transparent adult zebrafish using double pigmentation mutant, called casper, provide unparalleled imaging power in in vivo longitudinal analysis of biological processes at an anatomic resolution not readily achievable in murine or other systems. In this paper we introduce an optical method for simultaneous visualization and cell quantification, which combines the laser scanning confocal microscopy (LSCM) and the in vivo flow cytometry (IVFC). The system is designed specifically for non-invasive tracking of both stationary and circulating cells in adult zebrafish casper, under physiological conditions in the same fish over time. The confocal imaging part in this system serves the dual purposes of imaging fish tissue microstructure and a 3D navigation tool to locate a suitable vessel for circulating cell counting. The multi-color, multi-channel instrument allows the detection of multiple cell populations or different tissues or organs simultaneously. We demonstrate initial testing of this novel instrument by imaging vasculature and tracking circulating cells in CD41: GFP/Gata1: DsRed transgenic casper fish whose thrombocytes/erythrocytes express the green and red fluorescent proteins. Circulating fluorescent cell incidents were recorded and counted repeatedly over time and in different types of vessels. Great application opportunities in cancer and stem cell researches are discussed.

  4. Targeted Electroporation in Embryonic, Larval, and Adult Zebrafish.

    Science.gov (United States)

    Zou, Ming; Friedrich, Rainer W; Bianco, Isaac H

    2016-01-01

    This chapter describes three fast and straightforward methods to introduce nucleic acids, dyes, and other molecules into small numbers of cells of zebrafish embryos, larvae, and adults using electroporation. These reagents are delivered through a glass micropipette and electrical pulses are given through electrodes to permeabilize cell membranes and promote uptake of the reagent. This technique allows the experimenter to target cells of their choice at a particular time of development and at a particular location in the zebrafish with high precision and facilitates long-term noninvasive measurement of biological activities in vivo. Applications include cell fate mapping, neural circuit mapping, neuronal activity measurement, manipulation of activity, ectopic gene expression, and genetic knockdown experiments. PMID:27464813

  5. The Epicardium in the Embryonic and Adult Zebrafish

    Directory of Open Access Journals (Sweden)

    Marina Peralta

    2014-04-01

    Full Text Available The epicardium is the mesothelial outer layer of the vertebrate heart. It plays an important role during cardiac development by, among other functions, nourishing the underlying myocardium, contributing to cardiac fibroblasts and giving rise to the coronary vasculature. The epicardium also exerts key functions during injury responses in the adult and contributes to cardiac repair. In this article, we review current knowledge on the cellular and molecular mechanisms underlying epicardium formation in the zebrafish, a teleost fish, which is rapidly gaining status as an animal model in cardiovascular research, and compare it with the mechanisms described in other vertebrate models. We moreover describe the expression patterns of a subset of available zebrafish Wilms’ tumor 1 transgenic reporter lines and discuss their specificity, applicability and limitations in the study of epicardium formation.

  6. (Eco)toxicological effects of 2,4,7,9-tetramethyl-5-decyne-4,7-diol (TMDD) in zebrafish (Danio rerio) and permanent fish cell cultures.

    Science.gov (United States)

    Vincze, Krisztina; Gehring, Martin; Braunbeck, Thomas

    2014-01-01

    2,4,7,9-tetramethyl-5-decyne-4,7-diol (TMDD) is a high-production volume chemical used in paper, ink, pesticide, and adhesive industries as a wetting and anti-foaming agent. The physicochemical properties and slow biodegradation rate of TMDD indicate a low bioaccumulation potential but a high prevalence in the environment. As a consequence, TMDD has been detected in several European rivers in the nanogram per liter and lower microgram per liter range; however, its environmental risk to aquatic organisms is considered low. Recent studies almost exclusively focused on acute effects by TMDD, little is known about cytotoxic and genotoxic effects, reproduction and developmental toxicity, endocrine disruption, and any kind of long-term toxicity and carcinogenicity so far. The present study aims to provide more specific baseline information on the ecotoxicological effects of TMDD in fish. For this end, cyto- and genotoxicity assays were carried out in vitro with the permanent fish cell line RTL-W1; in addition, in vivo studies were conducted with the early life stages of zebrafish (Danio rerio) in order to fill the data gaps in developmental toxicity and endocrine disruption. TMDD showed a cytotoxic and slight genotoxic potential in fish cell lines; moreover, various sublethal and lethal effects could be detected in developing zebrafish embryos. There was no evidence of endocrine-disrupting effects by TMDD; however, mortality following prolonged exposure to TMDD during fish sexual development test was clearly higher than mortality in the fish embryo test after 96-h exposure. Our results thus confirmed previous findings of laboratory screening tests, suggesting short-term toxic effects of TMDD in the intermediate, and long-term effects in the lower milligram per liter range. PMID:24687796

  7. Structural models of zebrafish (Danio rerio NOD1 and NOD2 NACHT domains suggest differential ATP binding orientations: insights from computational modeling, docking and molecular dynamics simulations.

    Directory of Open Access Journals (Sweden)

    Jitendra Maharana

    Full Text Available Nucleotide-binding oligomerization domain-containing protein 1 (NOD1 and NOD2 are cytosolic pattern recognition receptors playing pivotal roles in innate immune signaling. NOD1 and NOD2 recognize bacterial peptidoglycan derivatives iE-DAP and MDP, respectively and undergoes conformational alternation and ATP-dependent self-oligomerization of NACHT domain followed by downstream signaling. Lack of structural adequacy of NACHT domain confines our understanding about the NOD-mediated signaling mechanism. Here, we predicted the structure of NACHT domain of both NOD1 and NOD2 from model organism zebrafish (Danio rerio using computational methods. Our study highlighted the differential ATP binding modes in NOD1 and NOD2. In NOD1, γ-phosphate of ATP faced toward the central nucleotide binding cavity like NLRC4, whereas in NOD2 the cavity was occupied by adenine moiety. The conserved 'Lysine' at Walker A formed hydrogen bonds (H-bonds and Aspartic acid (Walker B formed electrostatic interaction with ATP. At Sensor 1, Arg328 of NOD1 exhibited an H-bond with ATP, whereas corresponding Arg404 of NOD2 did not. 'Proline' of GxP motif (Pro386 of NOD1 and Pro464 of NOD2 interacted with adenine moiety and His511 at Sensor 2 of NOD1 interacted with γ-phosphate group of ATP. In contrast, His579 of NOD2 interacted with the adenine moiety having a relatively inverted orientation. Our findings are well supplemented with the molecular interaction of ATP with NLRC4, and consistent with mutagenesis data reported for human, which indicates evolutionary shared NOD signaling mechanism. Together, this study provides novel insights into ATP binding mechanism, and highlights the differential ATP binding modes in zebrafish NOD1 and NOD2.

  8. MECHANISMS UNDERLYING DIETHYLSTILBESTROL-INDUCED INHIBITION OF SPERMATOGENESIS IN ZEBRAFISH (DANIO RERIO)%己烯雌酚抑制斑马鱼精子发生及其可能的分子机制

    Institute of Scientific and Technical Information of China (English)

    谭号; 李英文; 尹盼; 刘智皓

    2015-01-01

    Diethylstilbestrol (DES) is a typical endocrine disruptor for aquatic animals in the Yangtze River of China. Here we investigated the effects of DES on testicular development and spermatogenesis of fish. Adult male zebrafish (Danio rerio) were used as experimental subjects and were exposed to DES (0.1, 1 and 10μg/L) for 20 days. The histo-logical results demonstrated that the DES exposure led to severe impacts on zebrafish spermatogenesis. To further elu-cidate mechanisms underlying this phenomenon, we cloned the cDNAs of vasa and dmc1 and analyzed their expression patterns at the tissue and cellular levels. Our results showed that vasa was exclusively expressed in spermatogonia and primary spermatocytes of testis, and that dmc1 was specifically expressed in spermatocytes of testis. Using semi-quantitative RT-PCR we found that DES dramatically suppressed the expressions of dmc1 in a dose- and time-dependent manner, but did not affect the expression of vasa. Moreover, the expression of dmrt1 (the male sex de-termining gene) and P450 11β(the key enzyme responsible for 11-KT synthesis) were also suppressed by DES exposure. Given that these genes play a role in meiosis and spermatogenesis, we speculated that DES might induce the male germ cell apoptosis in zebrafish by suppressing the expression of dmrt1 and P450 11β, and might inhibit the expression of dmc1 which result in impeded meiosis.%为研究内分泌干扰物己烯雌酚(DES)对鱼类精巢发育和配子发生的影响,研究用DES(0.1、1和10µg/L,暴露20d)对内分泌干扰研究的经典模式动物——斑马鱼(Danio rerio)雄性成鱼进行了处理。组织学研究结果表明, DES严重影响斑马鱼精子发生。同时,研究克隆了斑马鱼与生殖细胞发育和减数分裂相关的vasa、dmc1的部分cDNA,对其组织和细胞表达模式进行了研究。结果表明, vasa仅表达于精巢的精原细胞、初级精母细胞和卵巢不同时期的生殖细胞;而dmc1则表达于

  9. In vivo high field magnetic resonance imaging and spectroscopy of adult zebrafish

    NARCIS (Netherlands)

    Kabli, Samira

    2009-01-01

    This thesis contains the results of imaging of adult zebrafish by using different MR approaches. We present the first high resolution mMR images of adult zebrafish. To achieve high spatial resolution we used a magnetic field of 9.4T, in combination with strong magnetic field gradients (1000 mT/m) an

  10. The zebrafish (Danio rerio) embryo as a model system for identification and characterization of developmental toxins from marine and freshwater microalgae.

    Science.gov (United States)

    Berry, John P; Gantar, Miroslav; Gibbs, Patrick D L; Schmale, Michael C

    2007-02-01

    The zebrafish (Danio rerio) embryo has emerged as an important model of vertebrate development. As such, this model system is finding utility in the investigation of toxic agents that inhibit, or otherwise interfere with, developmental processes (i.e. developmental toxins), including compounds that have potential relevance to both human and environmental health, as well as biomedicine. Recently, this system has been applied increasingly to the study of microbial toxins, and more specifically, as an aquatic animal model, has been employed to investigate toxins from marine and freshwater microalgae, including those classified among the so-called "harmful algal blooms" (HABs). We have developed this system for identification and characterization of toxins from cyanobacteria (i.e. "blue-green algae") isolated from the Florida Everglades and other freshwater sources in South and Central Florida. Here we review the use of this system as it has been applied generally to the investigation of toxins from marine and freshwater microalgae, and illustrate this utility as we have applied it to the detection, bioassay-guided fractionation and subsequent characterization of developmental toxins from freshwater cyanobacteria. PMID:17020820

  11. Histopathological alterations and induction of hsp70 in ramshorn snail (Marisa cornuarietis) and zebrafish (Danio rerio) embryos after exposure to PtCl(2).

    Science.gov (United States)

    Osterauer, Raphaela; Köhler, Heinz-R; Triebskorn, Rita

    2010-08-01

    The platinum group metals (PGMs) platinum (Pt), palladium (Pd), and rhodium (Rh) are used in automobile catalytic converters, from which they have been emitted into the environment to an increasing degree during the last 20 years. Despite the bioavailability of these metals to plants and animals, studies determining the effects of PGMs on organisms are extremely rare. In the present study, effects of various concentrations of PtCl(2) (0.1, 1, 10, 50 and 100 microg/L) were investigated with respect to the induction of hsp70 and histopathological alterations in the zebrafish, Danio rerio and the ramshorn snail, Marisa cornuarietis. Histopathological investigations revealed effects of Pt on both species, which varied between slight and strong cellular reactions, depending on the PtCl(2) concentration. The hsp70 level in M. cornuarietis did not show an increase following Pt exposure whereas it was significantly elevated at 100 micorg/L PtCl(2) in D. rerio. PMID:20444508

  12. Does Physical Production of Nanoparticles Reduce Their Ecotoxicity? A Case of Lower Toxicity of AgNPs Produced by Laser Ablation to Zebrafish (Danio rerio

    Directory of Open Access Journals (Sweden)

    Seyed Ali Johari

    2014-09-01

    Full Text Available Use of nano-materials has increased in various aspects of human life. However, possible outbreak of nano-materials toxicity in humans and other organisms is one of the future challenges. Different chemical precursors which are used in chemical approaches for production of nano-materials may have secondary and sometimes toxic effects in living organisms. These secondary effects may be reduced in physical approaches due to not use of chemicals. To test this hypothesis, acute toxic effects of two types of silver nanoparticles (AgNPs which were produced by physical (top-down and chemical (bottom-up methods on survival rate of Zebrafish (Danio rerio were compared. According to the results, AgNPs produced by physical method were 38 times less toxic than ones generated by chemical method and therefore, the hypothesis was approved. The estimated 96 hr LC50 values of AgNPs produced by physical and chemical methods for zebra fish were 0.540 ± 0.032 and 0.014 ± 0.001 mg/L, respectively. According to these values and regarding the rules of European Union, both types of AgNPs are considered as highly toxic chemicals to aquatic organisms. Generally, AgNPs seems to have toxic effects on aquatic organisms regardless of the method used for their production, and so, their accidental or intentional entrance into the aquatic ecosystems should be inhibited.

  13. Completion of meiosis in male zebrafish (Danio rerio) despite lack of DNA mismatch repair gene mlh1

    NARCIS (Netherlands)

    Leal, M.C.; Feitsma, H.; Cuppen, E.; França, L.R.; Schulz, R.W.

    2008-01-01

    Mlh1 is a member of DNA mismatch repair (MMR) machinery and is also essential for the stabilization of crossovers during the first meiotic division. Recently, we have shown that zebrafish mlh1 mutant males are completely infertile because of a block in metaphase I, whereas females are fertile but ha

  14. Melatonin biosynthesizing enzyme genes and clock genes in ovary and whole brain of zebrafish (Danio rerio): Differential expression and a possible interplay.

    Science.gov (United States)

    Khan, Zeeshan Ahmad; Yumnamcha, Thangal; Rajiv, Chongtham; Devi, Haobijam Sanjita; Mondal, Gopinath; Devi, Sh Dharmajyoti; Bharali, Rupjyoti; Chattoraj, Asamanja

    2016-07-01

    The present study on zebrafish (Danio rerio) is the first attempt to demonstrate the circadian mRNA expression of melatonin biosynthesizing enzyme genes (Tph1a, Aanat1, Aanat2 and Hiomt) and clock associated genes (Bmal1a, Clock1a, Per1b, Per2 and Cry2a) in the ovary with a comparison to whole brain in normal (LD=12h L:12h D) and altered photic conditions (continuous dark, DD; continuous light, LL). Moreover, the present study also confirmed the ability of zebrafish ovary to biosynthesize melatonin both in vivo and in vitro with a significant difference at day and night. qRT-PCR analysis of genes revealed a dark acrophase of Aanat2 in both organs while Tph1 is in whole brain in LD condition. On the contrary, Bmal1a and Clock1a giving their peak in light, thereby showing a negative correlation with Tph1a and Aanat2. In LD-ovary, the acrophase of Tph1a, Bmal1a and Clock1a is in light and thus display a positive correlation. This trend of relationship in respect to Tph1a is not changing in altered photic conditions in both organs (except in DD-ovary). On the other hand this association for Aanat2 is varying in ovary under altered photic conditions but only in DD-whole brain. Both in LD and LL the expression of Aanat2 in brain presenting an opposite acrophase with both Bmal1a and Clock1a of ovary and consequently displaying a strong negative correlation among them. Interestingly, all ovarian clock associated genes become totally arrhythmic in DD, representing a loss of correlation between the melatonin synthesizing genes in brain and clock associated genes in ovary. The result is also indicating the formation of two heterodimers namely Clock1a:Bmal1a and Per2:Cry2a in the functioning of clock genes in both organs, irrespective of photic conditions, as they are exhibiting a strong significant positive correlation. Collectively, our data suggest that ovary of zebrafish is working as peripheral oscillator having its own melatonin biosynthesizing machinery and signifying a

  15. Development and recovery of histopathological alterations in the gonads of zebrafish (Danio rerio) after single and combined exposure to endocrine disruptors (17α-ethinylestradiol and fadrozole).

    Science.gov (United States)

    Luzio, Ana; Monteiro, Sandra M; Rocha, Eduardo; Fontaínhas-Fernandes, António A; Coimbra, Ana M

    2016-06-01

    Exposure of wildlife to endocrine disrupting chemicals (EDCs) is not necessarily continuous. Due to seasonal changes and variable industrial and agricultural activities it often occurs intermittently. Thus, it is possible that aquatic organisms may be more affected by periodic peak exposure than by chronic exposure. Therefore, an experimental scenario including an exposure from 2h to 90 days post-fertilization (dpf) and a subsequent recovery period until 150 dpf was chosen to assess the potential reversibility of the effects of sex steroids on sexual and gonad development of zebrafish (Danio rerio). The aim of this study was to investigate the persistence of the endocrine effects of an estrogen (EE2-17α-ethinylestradiol, 4ng/L), an inhibitor of estrogen synthesis (Fad-fadrozole, 50μg/L) or their binary mixture (Mix-EE2+ Fad, 4ng/L+50μg/L). Afterwards, a semi-quantitative histological assessment was used to investigate histopathological changes on gonad differentiation and development. The data showed that fadrozole, alone or in combination with EE2, permanently disrupts the sexual development, inducing masculinization and causing severe pathological alterations in testis, such as intersex associated to the enlargement of sperm ducts, interstitial changes, asynchronous development and detachment of basal membrane. After exposures to both EDCs and their mixture, the gonad histopathology revealed interstitial proteinaceous fluid deposits and, in ovaries, there were atretic oocytes, and presumably degenerative mineralization. On the other hand, the gonadal changes induced by EE2 alone seem to be partially reversible when the exposure regime changed to a recovery period. In addition, EE2 enhanced zebrafish growth in both genders, with male fish presenting signs of early obesity such as the presence of adipocytes in testis. Moreover, sex ratio was slightly skewed toward females, at 90 and 105 dpf, in zebrafish exposed to EE2. The data further indicate that long

  16. First molecular identification of the transgene red fluorescent protein (RFP in transgenic ornamental zebrafish (Danio rerio introduced in Peru

    Directory of Open Access Journals (Sweden)

    Carlos Scotto

    2013-09-01

    Full Text Available In this paper the transgenic fluorescent red, orange and pink zebra fish (Danio rerio, found in local aquariums in Peru, were identified using the PCR technique to amplify the transgene RFP sea anemone belonging to Discosoma spp. The gene expression of the red fluorescent protein (RFP transgene was found to determine different gradients-of-bioluminescence (shades in color in each GMO fish analyzed. We performed sequence analysis of the two variants of the RFP along with six variants of the existing fluorescent protein GFP from the Genbank, this could help identify quickly if they are new genes or variants thereof as these novel fluorescent proteins may be introduced in aquatic GMO in the future. Thus, developing and improving biosecurity measures through its timely detection at the molecular genetic level.

  17. Neurobehavioural Changes and Brain Oxidative Stress Induced by Acute Exposure to GSM900 Mobile Phone Radiations in Zebrafish (Danio rerio).

    Science.gov (United States)

    Nirwane, Abhijit; Sridhar, Vinay; Majumdar, Anuradha

    2016-04-01

    The impact of mobile phone (MP) radiation on the brain is of specific interest to the scientific community and warrants investigations, as MP is held close to the head. Studies on humans and rodents revealed hazards MP radiation associated such as brain tumors, impairment in cognition, hearing etc. Melatonin (MT) is an important modulator of CNS functioning and is a neural antioxidant hormone. Zebrafish has emerged as a popular model organism for CNS studies. Herein, we evaluated the impact of GSM900MP (GSM900MP) radiation exposure daily for 1 hr for 14 days with the SAR of 1.34W/Kg on neurobehavioral and oxidative stress parameters in zebrafish. Our study revealed that, GSM900MP radiation exposure, significantly decreased time spent near social stimulus zone and increased total distance travelled, in social interaction test. In the novel tank dive test, the GSM900MP radiation exposure elicited anxiety as revealed by significantly increased time spent in bottom half; freezing bouts and duration and decreased distance travelled, average velocity, and number of entries to upper half of the tank. Exposed zebrafish spent less time in the novel arm of the Y-Maze, corroborating significant impairment in learning as compared to the control group. Exposure decreased superoxide dismutase (SOD), catalase (CAT) activities whereas, increased levels of reduced glutathione (GSH) and lipid peroxidation (LPO) was encountered showing compromised antioxidant defense. Treatment with MT significantly reversed the above neurobehavioral and oxidative derangements induced by GSM900MP radiation exposure. This study traced GSM900MP radiation exposure induced neurobehavioral aberrations and alterations in brain oxidative status. Furthermore, MT proved to be a promising therapeutic candidate in ameliorating such outcomes in zebrafish. PMID:27123163

  18. Dopamine receptors participate in acquisition and consolidation of latent learning of spatial information in zebrafish (Danio rerio).

    Science.gov (United States)

    Naderi, Mohammad; Jamwal, Ankur; Ferrari, Maud C O; Niyogi, Som; Chivers, Douglas P

    2016-06-01

    There is growing appreciation that various aspects of learning and memory are strongly influenced by dopamine neurotransmission, and that zebrafish hold particular promise in the study of neurotransmitter systems. In this study, we sought to investigate the effect of dopamine receptors on acquisition and consolidation of memory in zebrafish using a latent learning paradigm. To this end, fish were subjected to a 30 min training trial each day for 16 days during which fish were allowed to freely explore a complex maze with the left or right path blocked and without the presence of a reward. During 16 days fish were treated with dopaminergic agonists (apomorphine, SKF-38393, and quinpirole) and antagonists (SCH-23390 and eticlopride) before or after training trials. To assess cognitive performance of fish, a subsequent probe trial was performed on day 17 while all paths leading to a reward chamber were open and the maze now contained stimulus fish as a reward. Pre- and post-training exposure to apomorphine, SKF-38393, and quinpirole significantly impaired learning and memory in fish. In contrast, fish exposed to eticlopride before and after training exhibited improved performance in a latent learning task. Administration of SCH-23390 before training did not affect zebrafish learning ability, but produced significant memory enhancement when given after training trials. Taken together, these findings are the first indications that D1 and D2 receptors are critically involved in acquisition and consolidation of latent learning in zebrafish, with a more prominent role for D2 receptors. The current study opens the door to future studies to investigate the involvement of dopamine receptors in various aspects of cognitive processes. PMID:26772761

  19. Neurobehavioural Changes and Brain Oxidative Stress Induced by Acute Exposure to GSM900 Mobile Phone Radiations in Zebrafish (Danio rerio)

    Science.gov (United States)

    Nirwane, Abhijit; Sridhar, Vinay; Majumdar, Anuradha

    2016-01-01

    The impact of mobile phone (MP) radiation on the brain is of specific interest to the scientific community and warrants investigations, as MP is held close to the head. Studies on humans and rodents revealed hazards MP radiation associated such as brain tumors, impairment in cognition, hearing etc. Melatonin (MT) is an important modulator of CNS functioning and is a neural antioxidant hormone. Zebrafish has emerged as a popular model organism for CNS studies. Herein, we evaluated the impact of GSM900MP (GSM900MP) radiation exposure daily for 1 hr for 14 days with the SAR of 1.34W/Kg on neurobehavioral and oxidative stress parameters in zebrafish. Our study revealed that, GSM900MP radiation exposure, significantly decreased time spent near social stimulus zone and increased total distance travelled, in social interaction test. In the novel tank dive test, the GSM900MP radiation exposure elicited anxiety as revealed by significantly increased time spent in bottom half; freezing bouts and duration and decreased distance travelled, average velocity, and number of entries to upper half of the tank. Exposed zebrafish spent less time in the novel arm of the Y-Maze, corroborating significant impairment in learning as compared to the control group. Exposure decreased superoxide dismutase (SOD), catalase (CAT) activities whereas, increased levels of reduced glutathione (GSH) and lipid peroxidation (LPO) was encountered showing compromised antioxidant defense. Treatment with MT significantly reversed the above neurobehavioral and oxidative derangements induced by GSM900MP radiation exposure. This study traced GSM900MP radiation exposure induced neurobehavioral aberrations and alterations in brain oxidative status. Furthermore, MT proved to be a promising therapeutic candidate in ameliorating such outcomes in zebrafish. PMID:27123163

  20. Impact of a novel protein meal on the gastrointestinal microbiota and host transcriptome of larval zebrafish Danio rerio

    Directory of Open Access Journals (Sweden)

    Eugene eRurangwa

    2015-04-01

    Full Text Available Larval zebrafish was subjected to a methodological exploration of the gastrointestinal microbiota and transcriptome. Assessed was the impact of two dietary inclusion levels of a novel protein meal (NPM of animal origin (ragworm Nereis virens on the gastrointestinal tract (GIT. Microbial development was assessed over the first 21 days post egg fertilisation (dpf through 16S rRNA gene-based microbial composition profiling by pyrosequencing. Differentially expressed genes in the GIT were demonstrated at 21 dpf by whole transcriptome sequencing (mRNAseq. Larval zebrafish showed rapid temporal changes in microbial colonization but domination occurred by one to three bacterial species generally belonging to Proteobacteria and Firmicutes. The high iron content of NPM may have led to an increased relative abundance of bacteria that were related to potential pathogens and bacteria with an increased iron metabolism. Functional classification of the 328 differentially expressed genes indicated that the GIT of larvae fed at higher NPM level was more active in transmembrane ion transport and protein synthesis. mRNAseq analysis did not reveal a major activation of genes involved in the immune response or indicating differences in iron uptake and homeostasis in zebrafish fed at the high inclusion level of NPM.

  1. Behavior Response Analysis of Zebrafish Danio rerio under Sudden Heavy Metal Stress%水体突发性重金属污染胁迫下斑马鱼的行为反应分析

    Institute of Scientific and Technical Information of China (English)

    黄东龙; 周勤

    2011-01-01

    研究了斑马鱼在不同程度突发性的Zn2+和Cr6+胁迫下的行为反应,采用计算机视觉技术量化研究斑马鱼游动行为数据.结果表明,在Zn2+和Cr6+的突发性胁迫中,斑马鱼的行为反应快速且敏感,游动行为与污染物种类、质量浓度和暴露时间直接相关,并表现出比较相似的行为变化规律;随着胁迫程度的增加,斑马鱼游动速度的变化幅度增大,反应时间缩短,且其变化曲线符合生物行为的环境压力模型.斑马鱼的行为变化远远提前于生物的病理损伤或死亡,可利用斑马鱼暴露于污染物时的行为变化实现在线水体突发性重金属污染事故的监测预警.%The data of swimming behavior was obtained by a computer vision system to study behavior response of zebrafish Danio rerio under sudden Zn2+ and Cr6+ stress. Result showed that the behavior response of zebrafish Danio rerio was sensitive to sudden Zn +and Cr + exposure, the behavioral responses of zebrafish Danio rerio, in accordance with the Stepwise Stress Model, were depended on exposure quality, concentration and exposure time directly. Increasing concentration resulted in more intensive swimming velocity of zebrafish Danio rerio with more short response time, which could be described by Stepwise Stress Model. The avoidance behavior was observed long before the injury or death of organisms so that behavioral responses under environment stress could be available to monitoring accidental pollution of heavy metal.

  2. Natural Variation in Fish Transcriptomes: Comparative Analysis of the Fathead Minnow (Pimephales promelas and Zebrafish (Danio rerio.

    Directory of Open Access Journals (Sweden)

    Rong-Lin Wang

    Full Text Available Fathead minnow and zebrafish are among the most intensively studied fish species in environmental toxicogenomics. To aid the assessment and interpretation of subtle transcriptomic effects from treatment conditions of interest, better characterization and understanding are needed for natural variation in gene expression among fish individuals from lab cultures. Leveraging the transcriptomics data from a number of our toxicogenomics studies conducted over the years, we conducted a meta-analysis of nearly 600 microarrays generated from the ovary tissue of untreated, reproductively mature fathead minnow and zebrafish samples. As expected, there was considerable batch-to-batch transcriptomic variation; this "batch-effect" appeared to differentially impact subsets of fish transcriptomes in a nonsystematic way. Temporally more closely spaced batches tended to share a greater transcriptomic similarity among one another. The overall level of within-batch variation was quite low in fish ovary tissue, making it a suitable system for studying chemical stressors with subtle biological effects. The observed differences in the within-batch variability of gene expression, at the levels of both individual genes and pathways, were probably both technical and biological. This suggests that biological interpretation and prioritization of genes and pathways targeted by experimental conditions should take into account both their intrinsic variability and the size of induced transcriptional changes. There was significant conservation of both the genomes and transcriptomes between fathead minnow and zebrafish. The high degree of conservation offers promising opportunities in not only studying fish molecular responses to environmental stressors by a comparative biology approach, but also effective sharing of a large amount of existing public transcriptomics data for developing toxicogenomics applications.

  3. Zebrafish as a model for bioavailability testing of over the counter drug

    Directory of Open Access Journals (Sweden)

    Sivamani S

    2013-06-01

    Full Text Available Zebrafish (Danio rerio has been an important model organism in a variety of biological disciplines. Presently it is well suited for studies in genetics, toxicology, behavioural neuroscience and developmental biology. Zebrafish embryos exhibit unique characteristics, including ease of maintenance and drug administration, short reproductive cycle, and embryo transparency that permits visual assessment of developing cells and organs. Because of these advantages, zebrafish bioassays are cheaper and faster than mouse assays, and are suitable for large-scale drug screening. In the present study, we investigate bioavailability of different drugs in adult zebrafish and compared our studies with fish fry. The effect of drug compounds on fish fry and in blood and liver of adult zebrafish were studied through thin layer chromatography (TLC. We hopeful that the use of these techniques or methods will make the zebrafish a prominent model in drug discovery and development research in the forthcoming years.

  4. Zebrafish: an animal model for research in veterinary medicine.

    Science.gov (United States)

    Nowik, N; Podlasz, P; Jakimiuk, A; Kasica, N; Sienkiewicz, W; Kaleczyc, J

    2015-01-01

    The zebrafish (Danio rerio) has become known as an excellent model organism for studies of vertebrate biology, vertebrate genetics, embryonal development, diseases and drug screening. Nevertheless, there is still lack of detailed reports about usage of the zebrafish as a model in veterinary medicine. Comparing to other vertebrates, they can lay hundreds of eggs at weekly intervals, externally fertilized zebrafish embryos are accessible to observation and manipulation at all stages of their development, which makes possible to simplify the research techniques such as fate mapping, fluorescent tracer time-lapse lineage analysis and single cell transplantation. Although zebrafish are only 2.5 cm long, they are easy to maintain. Intraperitoneal and intracerebroventricular injections, blood sampling and measurement of food intake are possible to be carry out in adult zebrafish. Danio rerio is a useful animal model for neurobiology, developmental biology, drug research, virology, microbiology and genetics. A lot of diseases, for which the zebrafish is a perfect model organism, affect aquatic animals. For a part of them, like those caused by Mycobacterium marinum or Pseudoloma neutrophila, Danio rerio is a natural host, but the zebrafish is also susceptible to the most of fish diseases including Itch, Spring viraemia of carp and Infectious spleen and kidney necrosis. The zebrafish is commonly used in research of bacterial virulence. The zebrafish embryo allows for rapid, non-invasive and real time analysis of bacterial infections in a vertebrate host. Plenty of common pathogens can be examined using zebrafish model: Streptococcus iniae, Vibrio anguillarum or Listeria monocytogenes. The steps are taken to use the zebrafish also in fungal research, especially that dealing with Candida albicans and Cryptococcus neoformans. Although, the zebrafish is used commonly as an animal model to study diseases caused by external agents, it is also useful in studies of metabolic

  5. Zebrafish: an animal model for research in veterinary medicine.

    Science.gov (United States)

    Nowik, N; Podlasz, P; Jakimiuk, A; Kasica, N; Sienkiewicz, W; Kaleczyc, J

    2015-01-01

    The zebrafish (Danio rerio) has become known as an excellent model organism for studies of vertebrate biology, vertebrate genetics, embryonal development, diseases and drug screening. Nevertheless, there is still lack of detailed reports about usage of the zebrafish as a model in veterinary medicine. Comparing to other vertebrates, they can lay hundreds of eggs at weekly intervals, externally fertilized zebrafish embryos are accessible to observation and manipulation at all stages of their development, which makes possible to simplify the research techniques such as fate mapping, fluorescent tracer time-lapse lineage analysis and single cell transplantation. Although zebrafish are only 2.5 cm long, they are easy to maintain. Intraperitoneal and intracerebroventricular injections, blood sampling and measurement of food intake are possible to be carry out in adult zebrafish. Danio rerio is a useful animal model for neurobiology, developmental biology, drug research, virology, microbiology and genetics. A lot of diseases, for which the zebrafish is a perfect model organism, affect aquatic animals. For a part of them, like those caused by Mycobacterium marinum or Pseudoloma neutrophila, Danio rerio is a natural host, but the zebrafish is also susceptible to the most of fish diseases including Itch, Spring viraemia of carp and Infectious spleen and kidney necrosis. The zebrafish is commonly used in research of bacterial virulence. The zebrafish embryo allows for rapid, non-invasive and real time analysis of bacterial infections in a vertebrate host. Plenty of common pathogens can be examined using zebrafish model: Streptococcus iniae, Vibrio anguillarum or Listeria monocytogenes. The steps are taken to use the zebrafish also in fungal research, especially that dealing with Candida albicans and Cryptococcus neoformans. Although, the zebrafish is used commonly as an animal model to study diseases caused by external agents, it is also useful in studies of metabolic

  6. An in vivo evaluation of acute toxicity of cobalt ferrite (CoFe2O4) nanoparticles in larval-embryo Zebrafish (Danio rerio).

    Science.gov (United States)

    Ahmad, Farooq; Liu, Xiaoyi; Zhou, Ying; Yao, Hongzhou

    2015-09-01

    The broad spectrum applications of CoFe2O4 NPs have attracted much interest in medicine, environment and industry, resulting in exceedingly higher exposures to humans and environmental systems in succeeding days. Their health effects and potential biological impacts need to be determined for risk assessment. Zebrafish (Danio rerio) embryos were exposed to environmentally relevant doses of nano-CoFe2O4 (mean diameter of 40nm) with a concentration range of 10-500μM for 96h. Acute toxic end points were evaluated by survival rate, malformation, hatching delay, heart dysfunction and tail flexure of larvae. Dose and time dependent developmental toxicity with severe cardiac edema, down regulation of metabolism, hatching delay and tail/spinal cord flexure and apoptosis was observed. The biochemical changes were evaluated by ROS, Catalase (CAT), Lipid peroxidation (LPO), Acid phophatase (AP) and Glutatione s- transferase (GST). An Agglomeration of NPs and dissolution of ions induces severe mechanical damage to membranes and oxidative stress. Severe apoptosis of cells in the head, heart and tail region with inhibition of catalase confirms ROS induced acute toxicity with increasing concentration. Increased activity of GST and AP at lower concentrations of CoFe2O4 NPs demonstrates the severe oxidative stress. Circular dichroism (CD) spectra indicated the weak interactions of NPs with BSA and slight changes in α-helix structure. In addition, CoFe2O4 NPs at lower concentrations do not show any considerable interference with assay components and analytical instruments. The results are possible elucidation of pathways of toxicity induced by these particles, as well as contributing in defining the protocols for risk assessment of these nanoparticles. PMID:26197244

  7. Cadmium sulfate and CdTe-quantum dots alter DNA repair in zebrafish (Danio rerio) liver cells

    International Nuclear Information System (INIS)

    Increasing use of quantum dots (QDs) makes it necessary to evaluate their toxicological impacts on aquatic organisms, since their contamination of surface water is inevitable. This study compares the genotoxic effects of ionic Cd versus CdTe nanocrystals in zebrafish hepatocytes. After 24 h of CdSO4 or CdTe QD exposure, zebrafish liver (ZFL) cells showed a decreased number of viable cells, an accumulation of Cd, an increased formation of reactive oxygen species (ROS), and an induction of DNA strand breaks. Measured levels of stress defense and DNA repair genes were elevated in both cases. However, removal of bulky DNA adducts by nucleotide excision repair (NER) was inhibited with CdSO4 but not with CdTe QDs. The adverse effects caused by acute exposure of CdTe QDs might be mediated through differing mechanisms than those resulting from ionic cadmium toxicity, and studying the effects of metallic components may be not enough to explain QD toxicities in aquatic organisms. - Highlights: • Both CdSO4 and CdTe QDs lead to cell death and Cd accumulation. • Both CdSO4 and CdTe QDs induce cellular ROS generation and DNA strand breaks. • Both CdSO4 and CdTe QDs induce the expressions of stress defense and DNA repair genes. • NER repair capacity was inhibited with CdSO4 but not with CdTe QDs

  8. The involvement of cholesterol in sepsis and tolerance to lipopolysaccharide highlighted by the transcriptome analysis of zebrafish (Danio rerio).

    Science.gov (United States)

    Dios, Sonia; Balseiro, Pablo; Costa, Maria M; Romero, Alejandro; Boltaña, Sebastián; Roher, Nerea; Mackenzie, Simon; Figueras, Antonio; Novoa, Beatriz

    2014-10-01

    Septic shock is the most common cause of death in intensive care units due to an aggressive inflammatory response that leads to multiple organ failure. However, a lipopolysaccharide (LPS) tolerance phenomenon (a nonreaction to LPS), is also often described. Neither the inflammatory response nor the tolerance is completely understood. In this work, both of these responses were analyzed using microarrays in zebrafish. Fish that were 4 or 6 days postfertilization (dpf) and received a lethal dose (LD) of LPS exhibited 100% mortality in a few days. Their transcriptome profile, even at 4 dpf, resembled the profile in humans with severe sepsis. Moreover, we selected 4-dpf fish to set up a tolerance protocol: fish treated with a nonlethal concentration of Escherichia coli LPS exhibited complete protection against the LD of LPS. Most of the main inflammatory molecules described in mammals were represented in the zebrafish microarray experiments. Additionally and focusing on this tolerance response, the use of cyclodextrins may mobilize cholesterol reservoirs to decrease mortality after a LD dose of LPS. Therefore, it is possible that the use of the whole animal could provide some clues to enhance the understanding of the inflammatory/tolerance response and to guide drug discovery.

  9. Cadmium sulfate and CdTe-quantum dots alter DNA repair in zebrafish (Danio rerio) liver cells

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Song; Cai, Qingsong [The Institute of Environmental and Human Health, Texas Tech University, Lubbock, TX 79416 (United States); Chibli, Hicham [Department of Biomedical Engineering, McGill University, Montréal, QC H3A 2B4 (Canada); Allagadda, Vinay [The Institute of Environmental and Human Health, Texas Tech University, Lubbock, TX 79416 (United States); Nadeau, Jay L. [Department of Biomedical Engineering, McGill University, Montréal, QC H3A 2B4 (Canada); Mayer, Gregory D., E-mail: greg.mayer@ttu.edu [The Institute of Environmental and Human Health, Texas Tech University, Lubbock, TX 79416 (United States)

    2013-10-15

    Increasing use of quantum dots (QDs) makes it necessary to evaluate their toxicological impacts on aquatic organisms, since their contamination of surface water is inevitable. This study compares the genotoxic effects of ionic Cd versus CdTe nanocrystals in zebrafish hepatocytes. After 24 h of CdSO{sub 4} or CdTe QD exposure, zebrafish liver (ZFL) cells showed a decreased number of viable cells, an accumulation of Cd, an increased formation of reactive oxygen species (ROS), and an induction of DNA strand breaks. Measured levels of stress defense and DNA repair genes were elevated in both cases. However, removal of bulky DNA adducts by nucleotide excision repair (NER) was inhibited with CdSO{sub 4} but not with CdTe QDs. The adverse effects caused by acute exposure of CdTe QDs might be mediated through differing mechanisms than those resulting from ionic cadmium toxicity, and studying the effects of metallic components may be not enough to explain QD toxicities in aquatic organisms. - Highlights: • Both CdSO{sub 4} and CdTe QDs lead to cell death and Cd accumulation. • Both CdSO{sub 4} and CdTe QDs induce cellular ROS generation and DNA strand breaks. • Both CdSO{sub 4} and CdTe QDs induce the expressions of stress defense and DNA repair genes. • NER repair capacity was inhibited with CdSO{sub 4} but not with CdTe QDs.

  10. Lagos lagoon sediment organic extracts and polycyclic aromatic hydrocarbons induce embryotoxic, teratogenic and genotoxic effects in Danio rerio (zebrafish) embryos.

    Science.gov (United States)

    Sogbanmu, Temitope O; Nagy, Eszter; Phillips, David H; Arlt, Volker M; Otitoloju, Adebayo A; Bury, Nic R

    2016-07-01

    An expansion of anthropogenic activity around Lagos lagoon, Nigeria, has raised concerns over increasing contaminants entering the lagoon's ecosystem. The embryotoxicity, teratogenicity and genotoxicity of sediment organic extracts from four sampling zones around Lagos lagoon, Ilaje, Iddo, Atlas Cove and Apapa, as well as the dominant polycyclic aromatic hydrocarbons (PAHs) identified in water measured during the wet season (naphthalene, phenanthrene, pyrene, benzo[a]pyrene and a mixture of these), were assessed with Danio rerio embryos. Embryos were exposed to varying concentrations of toxicants from 0-72 h post-fertilization (hpf). Embryotoxicity at 72 hpf showed a dose-dependent increase in mortality upon exposure to extracts from all zones, except Atlas Cove. Similarly, higher levels of teratogenic effects, such as increased oedema, and haemorrhage and developmental abnormalities resulted from exposure to extracts from Ilaje, Iddo and Apapa zones. Treatment with single PAHs revealed that significant levels of detrimental effects were obtained only for phenanthrene. The modified comet assay revealed that the oxidative damage to DNA was generally low (<12 %) overall for all sediment extracts, but was significantly elevated with Ilaje and Iddo sediment extracts when compared with solvent controls. Oxidative damage was observed with the single PAHs, phenanthrene and benzo[a]pyrene, as well as with the PAH mixture. This study highlights that Lagos lagoon sediment extracts have teratogenic, embryotoxic and genotoxic properties, which are likely due to the high molecular weight PAHs present in the extracts, some of which are known or are suspected human carcinogens. PMID:27068906

  11. Developmental toxicity and neurotoxicity of two matrine-type alkaloids, matrine and sophocarpine, in zebrafish (Danio rerio) embryos/larvae.

    Science.gov (United States)

    Lu, Zhao-Guang; Li, Ming-Hui; Wang, Jun-Song; Wei, Dan-Dan; Liu, Qing-Wang; Kong, Ling-Yi

    2014-08-01

    Matrine and sophocarpine are two major matrine-type alkaloids included in the traditional Chinese medicine (TCM) Kushen (the root of Sophora flavescens Ait.). They have been widely used clinically in China, however with few reports concerning their potential toxicities. This study investigated the developmental toxicity and neurotoxicity of matrine and sophocarpine on zebrafish embryos/larvae from 0 to 96/120h post fertilization (hpf). Both drugs displayed teratogenic and lethal effects with the EC50 and LC50 values at 145 and 240mg/L for matrine and 87.1 and 166mg/L for sophocarpine, respectively. Exposure of matrine and sophocarpine significantly altered spontaneous movement and inhibited swimming performance at concentrations below those causing lethality and malformations, indicating a neurotoxic potential of both drugs. The results are in agreement with most mammalian studies and clinical observations.

  12. Effects of Double Transgenesis of Somatotrophic Axis (GH/GHR) on Skeletal Muscle Growth of Zebrafish (Danio rerio).

    Science.gov (United States)

    Silva, Ana Cecilia Gomes; Almeida, Daniela Volcan; Nornberg, Bruna Felix; Figueiredo, Marcio Azevedo; Romano, Luis Alberto; Marins, Luis Fernando

    2015-12-01

    Transgenic fish for growth hormone (GH) has been considered as a potential technological improvement in aquaculture. In this study, a double-transgenic zebrafish was used to evaluate the effect of GH and its receptor (GHR) on muscle growth. Double transgenics reached the same length of GH transgenic, but with significantly less weight, featuring an unbalanced growth. The condition factor of GH/GHR-transgenic fish was lower than the other genotypes. Histological analysis showed a decrease in the percentage of thick muscle fibers in GH/GHR genotype of ∼ 80% in comparison to GH-transgenic line. The analysis of gene expression showed a significant decrease in genes related to muscle growth in GH/GHR genotype. It seems that concomitant overexpression of GH and GHR resulted in a strong decrease of the somatotrophic axis intracellular signaling by diminishing its principal transcription factor signal transducer and activator of transcription 5.1 (STAT5.1).

  13. Effects of Double Transgenesis of Somatotrophic Axis (GH/GHR) on Skeletal Muscle Growth of Zebrafish (Danio rerio).

    Science.gov (United States)

    Silva, Ana Cecilia Gomes; Almeida, Daniela Volcan; Nornberg, Bruna Felix; Figueiredo, Marcio Azevedo; Romano, Luis Alberto; Marins, Luis Fernando

    2015-12-01

    Transgenic fish for growth hormone (GH) has been considered as a potential technological improvement in aquaculture. In this study, a double-transgenic zebrafish was used to evaluate the effect of GH and its receptor (GHR) on muscle growth. Double transgenics reached the same length of GH transgenic, but with significantly less weight, featuring an unbalanced growth. The condition factor of GH/GHR-transgenic fish was lower than the other genotypes. Histological analysis showed a decrease in the percentage of thick muscle fibers in GH/GHR genotype of ∼ 80% in comparison to GH-transgenic line. The analysis of gene expression showed a significant decrease in genes related to muscle growth in GH/GHR genotype. It seems that concomitant overexpression of GH and GHR resulted in a strong decrease of the somatotrophic axis intracellular signaling by diminishing its principal transcription factor signal transducer and activator of transcription 5.1 (STAT5.1). PMID:26574627

  14. Glucocorticoid receptor, but not mineralocorticoid receptor, mediates cortisol regulation of epidermal ionocyte development and ion transport in zebrafish (danio rerio.

    Directory of Open Access Journals (Sweden)

    Shelly Abad Cruz

    Full Text Available Cortisol is the major endogenous glucocorticoid (GC both in human and fish, mediated by corticosteroid receptors. Due to the absence of aldosterone production in teleost fish, cortisol is also traditionally accepted to function as mineralocorticoid (MC; but whether it acts through the glucocorticoid receptor (GR or the mineralocorticoid receptor (MR remains a subject of debate. Here, we used loss-of-function and rescue assays to determine whether cortisol affects zebrafish epidermal ionocyte development and function via the GR and/or the MR. GR knockdown morphants displayed a significant decrease in the major ionocytes, namely Na(+-K(+-ATPase-rich cells (NaRCs and H(+-ATPase-rich cells (HRCs, as well as other cells, including epidermal stem cells (ESCs, keratinocytes, and mucus cells; conversely, cell numbers were unaffected in MR knockdown morphants. In agreement, GR morphants, but not MR morphants, exhibited decreased NaRC-mediated Ca(2+ uptake and HRC-mediated H(+ secretion. Rescue via GR capped mRNA injection or exogenous cortisol incubation normalized the number of epidermal ionocytes in GR morphants. We also provide evidence for GR localization in epidermal cells. At the transcript level, GR mRNA is ubiquitously expressed in gill sections and present in both NaRCs and HRCs, supporting the knockdown and functional assay results in embryo. Altogether, we have provided solid molecular evidence that GR is indeed present on ionocytes, where it mediates the effects of cortisol on ionocyte development and function. Hence, cortisol-GR axis performs the roles of both GC and MC in zebrafish skin and gills.

  15. Cartilage and bone malformations in the head of zebrafish (Danio rerio) embryos following exposure to disulfiram and acetic acid hydrazide

    Energy Technology Data Exchange (ETDEWEB)

    Strecker, Ruben, E-mail: Ruben.Strecker@cos.uni-heidelberg.de [Aquatic Ecology and Toxicology Section, Center for Organismal Studies, University of Heidelberg, Im Neuenheimer Feld 230, D-69120 Heidelberg (Germany); Weigt, Stefan, E-mail: stefan.weigt@merckgroup.com [Institute of Toxicology, Merck KGaA, 64293 Darmstadt (Germany); Braunbeck, Thomas, E-mail: braunbeck@uni-hd.de [Aquatic Ecology and Toxicology Section, Center for Organismal Studies, University of Heidelberg, Im Neuenheimer Feld 230, D-69120 Heidelberg (Germany)

    2013-04-15

    In order to investigate teratogenic effects, especially on cartilage and bone formation, zebrafish embryos were exposed for 144 h to the dithiocarbamate pesticide disulfiram (20–320 μg/L) and acetic acid hydrazide (0.375–12 g/L), a degradation product of isoniazid. After fixation and full-mount staining, disulfiram could be shown to induce strong cartilage malformations after exposure to ≥ 80 μg/L, whereas acetic acid hydrazide caused cartilage alterations only from 1.5 g/L. Undulating notochords occurred after exposure to disulfiram even at the lowest test concentration of 20 μg/L, whereas at the two lowest concentrations of acetic acid hydrazide (0.375 and 0.75 g/L) mainly fractures of the notochord were observed. Concentrations of acetic acid hydrazide ≥ 1.5 g/L resulted in undulated notochords similar to disulfiram. Cartilages and ossifications of the cranium, including the cleithrum, were individually analyzed assessing the severity of malformation and the degree of ossification in a semi-quantitative approach. Cartilages of the neurocranium such as the ethmoid plate proved to be more stable than cartilages of the pharyngeal skeleton such as Meckel's cartilage. Hence, ossification proved significantly more susceptible than cartilage. The alterations induced in the notochord as well as in the cranium might well be of ecological relevance, since notochord malformation is likely to result in impaired swimming and cranial malformation might compromise regular food uptake. - Highlights: ► Disulfiram and acetic acid hydrazide as notochord, cartilage and bone teratogens ► Zebrafish embryos to model effects on single cartilages and bones in the head ► LC50 calculation and head length measurements after six days post-fertilization ► Lethality, head length and teratogenic effects are dose-dependent. ► Cartilages of the neurocranium are the most stable elements in the head.

  16. The influence of dissolved organic matter (DOM) on sodium regulation and nitrogenous waste excretion in the zebrafish (Danio rerio).

    Science.gov (United States)

    Al-Reasi, Hassan A; Smith, Scott D; Wood, Chris M

    2016-08-01

    Dissolved organic matter (DOM) is both ubiquitous and diverse in composition in natural waters, but its effects on the branchial physiology of aquatic organisms have received little attention relative to other variables (e.g. pH, hardness, salinity, alkalinity). Here, we investigated the effects of four chemically distinct DOM isolates (three natural, one commercial, ranging from autochthonous to highly allochthonous, all at ∼6 mg C l(-1)) on the physiology of gill ionoregulation and nitrogenous waste excretion in zebrafish acclimated to either circumneutral (7.0-8.0) or acidic pH (5.0). Overall, lower pH tended to increase net branchial ammonia excretion, net K(+) loss and [(3)H]PEG-4000 clearance rates (indicators of transcellular and paracellular permeability, respectively). However, unidirectional Na(+) efflux, urea excretion and drinking rates were unaffected. DOM sources tended to stimulate unidirectional Na(+) influx rate and exerted subtle effects on the concentration-dependent kinetics of Na(+) uptake, increasing maximum transport capacity. All DOM sources reduced passive Na(+) efflux rates regardless of pH, but exerted negligible effects on nitrogenous waste excretion, drinking rate, net K(+) loss or [(3)H]PEG-4000 clearance, so the mechanism of Na(+) loss reduction remains unclear. Overall, these actions appear beneficial to ionoregulatory homeostasis in zebrafish, and some may be related to physico-chemical properties of the DOM sources. They are very different from those seen in a recent parallel study on Daphnia magna using the same DOM isolates, indicating that DOM actions may be both species and DOM specific.

  17. Zinc and cadmium accumulation in single zebrafish (Danio rerio) embryos - A total reflection X-ray fluorescence spectrometry application

    Energy Technology Data Exchange (ETDEWEB)

    Mages, Margarete [UFZ - Helmholtz Centre for Environmental Research, Dept. River Ecology Brueckstr. 3a/39114 Magdeburg/Germany (Germany); University of Lueneburg, Institute of Ecology and Environmental Chemistry, Department Environmental Chemistry, Scharnhorststrasse 1/21335 Lueneburg/Germany (Germany)], E-mail: margarete.mages@ufz.de; Bandow, Nicole [UFZ - Helmholtz Centre for Environmental Research, Dept. Effect Directed Analysis, Permoser Strasse 15/ 04318 Leipzig/Germany (Germany); Kuester, Eberhard [UFZ - Helmholtz Centre for Environmental Research, Dept. Bioanalytical Ecotoxicology, Permoser Strasse 15/ 04318 Leipzig/Germany (Germany); Brack, Werner [UFZ - Helmholtz Centre for Environmental Research, Dept. Effect Directed Analysis, Permoser Strasse 15/ 04318 Leipzig/Germany (Germany); Tuempling, Wolf von [UFZ - Helmholtz Centre for Environmental Research, Dept. River Ecology Brueckstr. 3a/39114 Magdeburg/Germany (Germany)

    2008-12-15

    Trace metals such as Cadmium (Cd) and Zinc (Zn) are known to exhibit adverse effects on many aquatic organisms including early life stages of fish. In contact with contaminated sediment, fish eggs and embryos may be exposed to metals via the water phase as well as via direct contact with contaminated particles. This may result in body burdens that are difficult to predict and may vary according to individual micro scale exposure conditions. The highly sensitive total reflection X-ray fluorescence spectrometry (TXRF) may provide a tool to analyse individual embryos for internal contaminant concentrations and thus helps to develop a better understanding of dose-response relationships. To test this hypothesis, embryos of Danio rerio were exposed to Cd and Zn spiked sediment in different treatments applying an ion exchange resin for modification of bioavailable concentrations. The TXRF analysis indicated individual embryos with dramatically enhanced exposure compared to other individuals despite uniform exposure conditions on a macro scale. Ion exchanger reduced embryo Zn concentrations to values close to control value with a comparably low standard deviation. Cadmium concentrations in embryos were in the range of 4000 to 7000 {mu}g/g with a median of 5740 {mu}g/g. A commercial ion exchanger reduced individual body burdens by a factor 50 to 100. Individual peak body burdens of up to 3160 {mu}g/g were accompanied by reduced weight of the fish eggs due to early death i.e. coagulation. The investigation of exposure and effects on an individual-based scale may significantly help to reduce uncertainty and inconsistencies occurring in conventional analysis of pooled fish embryo samples.

  18. Kisspeptins modulate the biology of multiple populations of gonadotropin-releasing hormone neurons during embryogenesis and adulthood in zebrafish (Danio rerio.

    Directory of Open Access Journals (Sweden)

    Yali Zhao

    Full Text Available Kisspeptin1 (product of the Kiss1 gene is the key neuropeptide that gates puberty and maintains fertility by regulating the gonadotropin-releasing hormone (GnRH neuronal system in mammals. Inactivating mutations in Kiss1 and the kisspeptin receptor (GPR54/Kiss1r are associated with pubertal failure and infertility. Kiss2, a paralogous gene for kiss1, has been recently identified in several vertebrates including zebrafish. Using our transgenic zebrafish model system in which the GnRH3 promoter drives expression of emerald green fluorescent protein, we investigated the effects of kisspeptins on development of the GnRH neuronal system during embryogenesis and on electrical activity during adulthood. Quantitative PCR showed detectable levels of kiss1 and kiss2 mRNA by 1 day post fertilization, increasing throughout embryonic and larval development. Early treatment with Kiss1 or Kiss2 showed that both kisspeptins stimulated proliferation of trigeminal GnRH3 neurons located in the peripheral nervous system. However, only Kiss1, but not Kiss2, stimulated proliferation of terminal nerve and hypothalamic populations of GnRH3 neurons in the central nervous system. Immunohistochemical analysis of synaptic vesicle protein 2 suggested that Kiss1, but not Kiss2, increased synaptic contacts on the cell body and along the terminal nerve-GnRH3 neuronal processes during embryogenesis. In intact brain of adult zebrafish, whole-cell patch clamp recordings of GnRH3 neurons from the preoptic area and hypothalamus revealed opposite effects of Kiss1 and Kiss2 on spontaneous action potential firing frequency and membrane potential. Kiss1 increased spike frequency and depolarized membrane potential, whereas Kiss2 suppressed spike frequency and hyperpolarized membrane potential. We conclude that in zebrafish, Kiss1 is the primary stimulator of GnRH3 neuronal development in the embryo and an activator of stimulating hypophysiotropic neuron activities in the adult, while

  19. Uptake, depuration and bioconcentration of bisphenol AF (BPAF) in whole-body and tissues of zebrafish (Danio rerio).

    Science.gov (United States)

    Shi, Jiachen; Yang, Yunjia; Zhang, Jing; Feng, Yixing; Shao, Bing

    2016-10-01

    Bisphenol AF (BPAF) is an analog of Bisphenol A (BPA) and is widely used as a raw material in the plastics industry. However, an understanding of the potential risks posed by BPAF in the aquatic environment is lacking. The bioconcentration factor (BCF) is a measure used to assess the secondary poisoning potential as well as risks to human health. In this work we measured the accumulation and elimination of BPAF in the whole-body and in liver, muscle and gonad tissues of zebrafish. BPAF uptake was relatively rapid with equilibrium concentrations reached after 24-72h of exposure. We observed gender differences both in whole-body and in tissue accumulation. Muscle was the primary BPAF storage tissue during the uptake phase in this study. In the elimination phase, BPAF concentrations declined rapidly during depuration, especially during the initial 2h, and the rate of elimination in males was faster than females from the whole-body and from tissues. The appearance of BPAF glucuronide (BPAF-G) at the start of the uptake phase indicated the rapid biotransformation of BPAF to BPAF-G in vivo. The high lipid content of female gonad could act to delay the diffusion of the xenobiotic within the body in a contaminated environment, but it also acts to delay xenobiotic elimination from the body. PMID:27362491

  20. Metabolism of clofibric acid in zebrafish embryos (Danio rerio) as determined by liquid chromatography-high resolution-mass spectrometry.

    Science.gov (United States)

    Brox, Stephan; Seiwert, Bettina; Haase, Nora; Küster, Eberhard; Reemtsma, Thorsten

    2016-01-01

    The zebrafish embryo (ZFE) is increasingly used in ecotoxicology research but detailed knowledge of its metabolic potential is still limited. This study focuses on the xenobiotic metabolism of ZFE at different life-stages using the pharmaceutical compound clofibric acid as study compound. Liquid chromatography with quadrupole-time-of-flight mass spectrometry (LC-QToF-MS) is used to detect and to identify the transformation products (TPs). In screening experiments, a total of 18 TPs was detected and structure proposals were elaborated for 17 TPs, formed by phase I and phase II metabolism. Biotransformation of clofibric acid by the ZFE involves conjugation with sulfate or glucuronic acid, and, reported here for the first time, with carnitine, taurine, and aminomethanesulfonic acid. Further yet unknown cyclization products were identified using non-target screening that may represent a new detoxification pathway. Sulfate containing TPs occurred already after 3h of exposure (7hpf), and from 48h of exposure (52hpf) onwards, all TPs were detected. The detection of these TPs indicates the activity of phase I and phase II enzymes already at early life-stages. Additionally, the excretion of one TP into the exposure medium was observed. The results of this study outline the high metabolic potential of the ZFE with respect to the transformation of xenobiotics. Similarities but also differences to other test systems were observed. Biotransformation of test chemicals in toxicity testing with ZFE may therefore need further consideration. PMID:26945519

  1. Studies on the toxic effects of microcystin-LR on the zebrafish (Danio rerio) under different temperatures.

    Science.gov (United States)

    Zhang, Xuezhen; Ji, Wei; Zhang, Huan; Zhang, Wei; Xie, Ping

    2011-08-01

    It is well known that fish have stronger tolerance than mammals to microcystin (MC) exposure, and such a difference is attributed to their different core body temperatures. However, no in vivo study has been conducted to investigate the effects of temperature on MC-induced toxicity in fish, a typical poikilotherm. Tolerance and detoxification response of zebrafish treated with MC-LR were investigated under three temperatures. The LD50 values evidently increased with a decline of the temperature (547, 260 and 176 µg kg⁻¹ at 12, 22 and 32 °C, respectively), indicating stronger tolerance of the fish at lower temperatures. Changes in the transcription of glutathione S-transferase (GST) isoforms in the fish were observed, and their sensitivity of response in the transcription of GST mRNA was on the order of 12 > 32 > 22°C. We screened out several GST genes which were more delicate to solve the MC-LR exposure at different temperatures, i.e. GST rho1, al, p1 and theta1 in the 12 °C group, and GST zeta1 and p2 in the 22 and 32 °C groups. Our findings partly validate the hypothesis that high temperature enhances toxic effects of MCs on poikilotherms. Our studies also indicate that temperature-dependent toxic effects should be taken into account for field toxic assessment of microcystins in fish. PMID:21089159

  2. Metabolism of clofibric acid in zebrafish embryos (Danio rerio) as determined by liquid chromatography-high resolution-mass spectrometry.

    Science.gov (United States)

    Brox, Stephan; Seiwert, Bettina; Haase, Nora; Küster, Eberhard; Reemtsma, Thorsten

    2016-01-01

    The zebrafish embryo (ZFE) is increasingly used in ecotoxicology research but detailed knowledge of its metabolic potential is still limited. This study focuses on the xenobiotic metabolism of ZFE at different life-stages using the pharmaceutical compound clofibric acid as study compound. Liquid chromatography with quadrupole-time-of-flight mass spectrometry (LC-QToF-MS) is used to detect and to identify the transformation products (TPs). In screening experiments, a total of 18 TPs was detected and structure proposals were elaborated for 17 TPs, formed by phase I and phase II metabolism. Biotransformation of clofibric acid by the ZFE involves conjugation with sulfate or glucuronic acid, and, reported here for the first time, with carnitine, taurine, and aminomethanesulfonic acid. Further yet unknown cyclization products were identified using non-target screening that may represent a new detoxification pathway. Sulfate containing TPs occurred already after 3h of exposure (7hpf), and from 48h of exposure (52hpf) onwards, all TPs were detected. The detection of these TPs indicates the activity of phase I and phase II enzymes already at early life-stages. Additionally, the excretion of one TP into the exposure medium was observed. The results of this study outline the high metabolic potential of the ZFE with respect to the transformation of xenobiotics. Similarities but also differences to other test systems were observed. Biotransformation of test chemicals in toxicity testing with ZFE may therefore need further consideration.

  3. New tools for the identification of developmentally regulated enhancer regions in embryonic and adult zebrafish.

    Science.gov (United States)

    Levesque, Mitchell P; Krauss, Jana; Koehler, Carla; Boden, Cindy; Harris, Matthew P

    2013-03-01

    We have conducted a screen to identify developmentally regulated enhancers that drive tissue-specific Gal4 expression in zebrafish. We obtained 63 stable transgenic lines with expression patterns in embryonic or adult zebrafish. The use of a newly identified minimal promoter from the medaka edar locus resulted in a relatively unbiased set of expression patterns representing many tissue types derived from all germ layers. Subsequent detailed characterization of selected lines showed strong and reproducible Gal4-driven GFP expression in diverse tissues, including neurons from the central and peripheral nervous systems, pigment cells, erythrocytes, and peridermal cells. By screening adults for GFP expression, we also isolated lines expressed in tissues of the adult zebrafish, including scales, fin rays, and joints. The new and efficient minimal promoter and large number of transactivating driver-lines we identified will provide the zebrafish community with a useful resource for further enhancer trap screening, as well as precise investigation of tissue-specific processes in vivo.

  4. Toxicological responses following short-term exposure through gavage feeding or water-borne exposure to Dechlorane Plus in zebrafish (Danio rerio).

    Science.gov (United States)

    Kang, Habyeong; Moon, Hyo-Bang; Choi, Kyungho

    2016-03-01

    Dechlorane Plus (DP) is a chlorinated flame retardant widely used worldwide, and has been reported in environment and humans. However, only limited information is currently available on its toxicity on aquatic organisms. In this study, we employed zebrafish to evaluate possible toxicological responses including oxidative stress and endocrine disruption following exposure to DP. DP was dissolved in corn oil and was delivered to adult male zebrafish via gavage feeding. Delivery of DP was carried out twice on days 0 and 2, at up to 3 μg/g fish wet weight. Body residue level of DP in the fish at day 6 was within a range that has been reported in hot spot areas of China. On day 6, blood, liver, testis, and brain were collected and were evaluated for oxidative damage and endocrine disruption. Following DP exposure, hepatic catalase activity significantly increased, implying its oxidative damage potential. In addition, plasma thyroxine (T4) concentrations increased along with up-regulation of corticotropin releasing hormone and thyroid stimulating hormone β genes in brain. Following DP exposure, transcriptional responses of sex hormone related genes in brain were observed, suggesting possible sex hormone disrupting potentials of DP. However, water-borne exposure to DP up to 267 μg/L among the embryo and larval fish did not show any adverse effects on hatching time and transcription of thyroid hormone related genes. Our observations indicate for the first time that DP disrupts thyroid hormone balance of zebrafish by altering regulatory pathways in the brain. Handling editor: David Volz. PMID:26735721

  5. Advanced echocardiography in adult zebrafish reveals delayed recovery of heart function after myocardial cryoinjury.

    Directory of Open Access Journals (Sweden)

    Selina J Hein

    Full Text Available Translucent zebrafish larvae represent an established model to analyze genetics of cardiac development and human cardiac disease. More recently adult zebrafish are utilized to evaluate mechanisms of cardiac regeneration and by benefiting from recent genome editing technologies, including TALEN and CRISPR, adult zebrafish are emerging as a valuable in vivo model to evaluate novel disease genes and specifically validate disease causing mutations and their underlying pathomechanisms. However, methods to sensitively and non-invasively assess cardiac morphology and performance in adult zebrafish are still limited. We here present a standardized examination protocol to broadly assess cardiac performance in adult zebrafish by advancing conventional echocardiography with modern speckle-tracking analyses. This allows accurate detection of changes in cardiac performance and further enables highly sensitive assessment of regional myocardial motion and deformation in high spatio-temporal resolution. Combining conventional echocardiography measurements with radial and longitudinal velocity, displacement, strain, strain rate and myocardial wall delay rates after myocardial cryoinjury permitted to non-invasively determine injury dimensions and to longitudinally follow functional recovery during cardiac regeneration. We show that functional recovery of cryoinjured hearts occurs in three distinct phases. Importantly, the regeneration process after cryoinjury extends far beyond the proposed 45 days described for ventricular resection with reconstitution of myocardial performance up to 180 days post-injury (dpi. The imaging modalities evaluated here allow sensitive cardiac phenotyping and contribute to further establish adult zebrafish as valuable cardiac disease model beyond the larval developmental stage.

  6. Regulation of gonadal sex ratios and pubertal development by the thyroid endocrine system in zebrafish (Danio rerio)

    Science.gov (United States)

    Sharma, Prakash; Patino, Reynaldo

    2013-01-01

    We examined associations between thyroid condition, gonadal sex and pubertal development in zebrafish. Seventy-two-hour postfertilization larvae were reared in untreated medium or in the presence of goitrogens (sodium perchlorate, 0.82 mM; methimazole, 0.15 and 0.3 mM) or thyroxine (1 and 10 nM) for 30 days. Thyrocyte height, gonadal sex and gonadal development were histologically determined at 45 and 60 days postfertilization (dpf). Thyrocyte hypertrophy, an index of hypothyroidism, was observed at 45 and 60 dpf in perchlorate-treated but only at 45 dpf in methimazole-treated fish. Similarly, gonadal sex ratios were biased toward ovaries relative to control animals at 45 and 60 dpf in perchlorate-treated fish but only at 45 dpf in methimazole-treated fish. Gonadal sex ratios were biased toward testes at 45 and 60 dpf in thyroxine-treated fish. Spermatogenesis was delayed in testes from goitrogen-treated fish at 60 dpf relative to control values, but was unaffected in testes from thyroxine-treated individuals. Oogenesis seemed to be nonspecifically delayed in all treatments relative to control at 60 dpf. This study confirmed the previously reported association between hypothyroid condition and ovarian-skewed ratios, and hyperthyroid condition and testicular-skewed ratios, and also showed that male pubertal development is specifically delayed by experimental hypothyroidism. The simultaneous recovery from the hypothyroid and ovary-inducing effects of methimazole by 60 dpf (27 days post-treatment) suggests that the ovary-skewing effect of goitrogens is reversible when thyroid conditions return to basal levels before developmental commitment of gonadal sex. Conversely, the masculinizing effect of hyperthyroidism seems to be stable and perhaps permanent.

  7. The effect of methylmercury exposure on early central nervous system development in the zebrafish (Danio rerio) embryo.

    Science.gov (United States)

    Hassan, S A; Moussa, E A; Abbott, L C

    2012-09-01

    Much attention is focused on environmental contamination by heavy metals. The heavy metal mercury is found worldwide and is ranked number 3 on the Comprehensive Environmental Response, Compensation and Liability Act substance list. We examined the effect of low-level methylmercury exposure on central nervous system development of wild-type zebrafish embryos (ZFEs) of the AB strain because methylmercury is the most common form of mercury to which humans are exposed in the environment. ZFEs were exposed to nine different concentrations of methylmercury [0 (negative control), 5, 10, 50, 80, 100, 200, 500 and 1000 parts per billion (μg l(-1) )] starting at 6 h post-fertilization, which is the time the neural tube is first beginning to form. ZFEs were exposed to 2% ethanol as positive controls (100% embryonic death). ZFEs were assessed at 30, 54, 72 and 96 h post-fertilization for changes in embryonic development, mortality, time of hatching and morphological deformities. No abnormalities were observed in ZFEs exposed to 5 μg l(-1) methylmercury. The time of hatching from the chorion was delayed in ZFEs exposed to methylmercury concentrations of 50 μg l(-1) or higher. Significantly more ZFEs exposed to 0, 5 or 10 μg l(-1) methylmercury successfully completed hatching compared with ZFEs exposed to 50 μg l(-1) or higher methylmercury. ZFEs exposed to more than 200 μg l(-1) methylmercury exhibited 100% embryonic mortality. The rate of cell proliferation within the neural tube was significantly decreased in embryos exposed to 10, 50 and 80 μg l(-1) methylmercury and there were no differences between these doses.

  8. Regulation of gonadal sex ratios and pubertal development by the thyroid endocrine system in zebrafish (Danio rerio).

    Science.gov (United States)

    Sharma, Prakash; Patiño, Reynaldo

    2013-04-01

    We examined associations between thyroid condition, gonadal sex and pubertal development in zebrafish. Seventy-two-hour postfertilization larvae were reared in untreated medium or in the presence of goitrogens (sodium perchlorate, 0.82 mM; methimazole, 0.15 and 0.3 mM) or thyroxine (1 and 10 nM) for 30 days. Thyrocyte height, gonadal sex and gonadal development were histologically determined at 45 and 60 days postfertilization (dpf). Thyrocyte hypertrophy, an index of hypothyroidism, was observed at 45 and 60 dpf in perchlorate-treated but only at 45 dpf in methimazole-treated fish. Similarly, gonadal sex ratios were biased toward ovaries relative to control animals at 45 and 60 dpf in perchlorate-treated fish but only at 45 dpf in methimazole-treated fish. Gonadal sex ratios were biased toward testes at 45 and 60 dpf in thyroxine-treated fish. Spermatogenesis was delayed in testes from goitrogen-treated fish at 60 dpf relative to control values, but was unaffected in testes from thyroxine-treated individuals. Oogenesis seemed to be nonspecifically delayed in all treatments relative to control at 60 dpf. This study confirmed the previously reported association between hypothyroid condition and ovarian-skewed ratios, and hyperthyroid condition and testicular-skewed ratios, and also showed that male pubertal development is specifically delayed by experimental hypothyroidism. The simultaneous recovery from the hypothyroid and ovary-inducing effects of methimazole by 60 dpf (27 days post-treatment) suggests that the ovary-skewing effect of goitrogens is reversible when thyroid conditions return to basal levels before developmental commitment of gonadal sex. Conversely, the masculinizing effect of hyperthyroidism seems to be stable and perhaps permanent.

  9. The influence of magnetic field on the spatial orientation in zebrafish Danio rerio (Hamilton and roach Rutilus rutilus (L.

    Directory of Open Access Journals (Sweden)

    Anastasia A. Batrakova

    2015-10-01

    The fishes’ movements in the arena were recorded by a Panasonic-HC-X900M video camera. We recorded the angle of preferred direction as the fish crossed the 10 cm radius from the centre of the arena. A Northward direction corresponds to 0/360 degrees. Rayleigh’s z-test for unimodal and axial distribution was used to evaluate the significance of the preferred direction. The significance of the differences between preferred directions in the control and experimental groups was estimated using Watson’s U2-test. D. rerio. Significant preference of a single direction was not observed in any of the experiments. However, control groups (GMF displayed a significant preference for the two opposite directions gravitating North and South (Figs. 1e, 1f, 1h. Among the experimental groups, bidirectional orientation was observed only by rotation of the horizontal component by 90 degrees clockwise (Fig. 1d. In this case, fish preferred Westward and Eastward directions. R. rutilus. Significant preference of the East-northeast direction was found. This direction matched the direction from the location where individuals were caught to the deep-water part of Rybinsk Reservoir (Fig. 2. On rotation of the horizontal component by 90 degrees clockwise, fish tended to move to the South-southeast. The angle between preferred directions in the experimental and control groups was 79.87 degrees. Differences in preferred directions between experimental and control groups were statistically significant (U2 = 0.38, p < 0.001. Many Teleosts are known to possess special cells which accumulate magnetite during ontogenesis and are used for magnetoreception (Walker, 2011. Magnetite was also found in tissues of zebrafish

  10. Effects of 4-methylbenzylidene camphor (4-MBC) on neuronal and muscular development in zebrafish (Danio rerio) embryos.

    Science.gov (United States)

    Li, Vincent Wai Tsun; Tsui, Mei Po Mirabelle; Chen, Xueping; Hui, Michelle Nga Yu; Jin, Ling; Lam, Raymond H W; Yu, Richard Man Kit; Murphy, Margaret B; Cheng, Jinping; Lam, Paul Kwan Sing; Cheng, Shuk Han

    2016-05-01

    The negative effects of overexposure to ultraviolet (UV) radiation in humans, including sunburn and light-induced cellular injury, are of increasing public concern. 4-Methylbenzylidene camphor (4-MBC), an organic chemical UV filter, is an active ingredient in sunscreen products. To date, little information is available about its neurotoxicity during early vertebrate development. Zebrafish embryos were exposed to various concentrations of 4-MBC in embryo medium for 3 days. In this study, a high concentration of 4-MBC, which is not being expected at the current environmental concentrations in the environment, was used for the purpose of phenotypic screening. Embryos exposed to 15 μM of 4-MBC displayed abnormal axial curvature and exhibited impaired motility. Exposure effects were found to be greatest during the segmentation period, when somite formation and innervation occur. Immunostaining of the muscle and axon markers F59, znp1, and zn5 revealed that 4-MBC exposure leads to a disorganized pattern of slow muscle fibers and axon pathfinding errors during the innervation of both primary and secondary motor neurons. Our results also showed reduction in AChE activity upon 4-MBC exposure both in vivo in the embryos (15 μM) and in vitro in mammalian Neuro-2A cells (0.1 μM), providing a possible mechanism for 4-MBC-induced muscular and neuronal defects. Taken together, our results have shown that 4-MBC is a teratogen and influences muscular and neuronal development, which may result in developmental defects. PMID:26888529

  11. Functional diversity of excitatory commissural interneurons in adult zebrafish

    Science.gov (United States)

    Björnfors, E Rebecka; El Manira, Abdeljabbar

    2016-01-01

    Flexibility in the bilateral coordination of muscle contraction underpins variable locomotor movements or gaits. While the locomotor rhythm is generated by ipsilateral excitatory interneurons, less is known about the commissural excitatory interneurons. Here we examined how the activity of the V0v interneurons – an important commissural neuronal class – varies with the locomotor speed in adult zebrafish. Although V0v interneurons are molecularly homogenous, their activity pattern during locomotion is not uniform. They consist of two distinct types dependent on whether they display rhythmicity or not during locomotion. The rhythmic V0v interneurons were further subdivided into three sub-classes engaged sequentially, first at slow then intermediate and finally fast locomotor speeds. Their order of recruitment is defined by scaling their synaptic current with their input resistance. Thus we uncover, in an adult vertebrate, a novel organizational principle for a key class of commissural interneurons and their recruitment pattern as a function of locomotor speed. DOI: http://dx.doi.org/10.7554/eLife.18579.001 PMID:27559611

  12. Oral exposure of adult zebrafish (Danio rerio) to 2,4,6-tribromophenol affects reproduction

    DEFF Research Database (Denmark)

    Halden, Anna Norman; Nyholm, Jenny Rattfelt; Andersson, Patrik L;

    2010-01-01

    The bromophenol 2,4,6-tribromophenol (TBP) is widely used as an industrial chemical, formed by degradation of tetrabromobisphenol-A, and it occurs naturally in marine organisms. Concentrations of TBP in fish have been related to intake via feed, but little is known about effects on fish health...

  13. Toxicity and endocrine disruption in zebrafish (Danio rerio) and two freshwater invertebrates (Daphnia magna and Moina macrocopa) after chronic exposure to mefenamic acid.

    Science.gov (United States)

    Collard, Hyo-rin Jung; Ji, Kyunghee; Lee, Sangwoo; Liu, Xiaoshan; Kang, Sungeun; Kho, Younglim; Ahn, Byeongwoo; Ryu, Jisung; Lee, Jaean; Choi, Kyungho

    2013-08-01

    Pharmaceuticals have been frequently detected in the aquatic environment. Their potential effects on the endocrine system in wildlife are of special concern because these alterations could lead to impaired reproduction. We evaluated ecotoxicities associated with long-term exposure to mefenamic acid (MFA) and potential endocrine disruption. For this purpose, acute and chronic toxicities of MFA on several aquatic organisms, including two cladocerans, Daphnia magna and Moina macrocopa, and a teleost, Danio rerio were evaluated. The 48 h acute median effective concentration (EC50) of D. magna and M. macrocopa was 17.16 mg/L and 2.93 mg/L, respectively. In chronic toxicity test, D. magna and M. macrocopa showed significant changes in reproduction (number of young per adult) after the exposure to 1.0 mg/L and 0.25 mg/L MFA, respectively. In early life stage exposure using D. rerio, significant decrease of larval survival was observed at 1 mg/L. Changes in vitellogenin (VTG) protein concentrations in 32 day post fertilization fish and vtgI mRNA expression in adult male fish suggest endocrine disruption potentials of MFA. Among the genes of hypothalamus-pituitary-gonad axis, transcriptions of gnrh, gnrhr, cyp19a, and cyp19b increased, supporting estrogenic potential of MFA. Along with histological changes in ovaries, the results of this study provide evidences of endocrine disruption capacity of MFA. However, the effective concentrations are orders of magnitude greater than those occurring in the ambient aquatic environment. PMID:23725676

  14. Normal anatomy and histology of the adult zebrafish.

    Science.gov (United States)

    Menke, Aswin L; Spitsbergen, Jan M; Wolterbeek, Andre P M; Woutersen, Ruud A

    2011-08-01

    The zebrafish has been shown to be an excellent vertebrate model for studying the roles of specific genes and signaling pathways. The sequencing of its genome and the relative ease with which gene modifications can be performed have led to the creation of numerous human disease models that can be used for testing the potential and the toxicity of new pharmaceutical compounds. Many pharmaceutical companies already use the zebrafish for prescreening purposes. So far, the focus has been on ecotoxicity and the effects on embryonic development, but there is a trend to expand the use of the zebrafish with acute, subchronic, and chronic toxicity studies that are currently still carried out with the more conventional test animals such as rodents. However, before we can fully realize the potential of the zebrafish as an animal model for understanding human development, disease, and toxicology, we must first greatly advance our knowledge of normal zebrafish physiology, anatomy, and histology. To further this knowledge, we describe, in the present article, location and histology of the major zebrafish organ systems with a brief description of their function.

  15. Dechlorination of the dietary nona-chlorinated toxaphene congeners 62 and 50 into the octa-chlorinated toxaphene congeners 44 and 40 in zebrafish (Danio rerio) and Atlantic salmon (Salmo salar)

    Energy Technology Data Exchange (ETDEWEB)

    Berntssen, M.H.G., E-mail: marc.berntssen@nifes.no [National Institute of Nutrition and Seafood Research (NIFES), Postbox 2029 Nordnes, 5817 Bergen (Norway); Lundebye, A.-K.; Hop-Johannessen, L.; Lock, E.-J. [National Institute of Nutrition and Seafood Research (NIFES), Postbox 2029 Nordnes, 5817 Bergen (Norway)

    2012-05-15

    Graphical abstract: - Abstract: The relative feed-to-fish accumulation and possible biotransformation of the nona-chlorinated toxaphene congeners currently included in EU-legislation (CHB-50 and -62) and the octa-chlorinated congeners recommended by the European Food Safety Authority to be included in future surveillance of fish samples (CHB-40, 41, and 44) were investigated in the present study. Model fish Danio rerio were fed either (a) diets spiked with a combination as well as the pure individual toxaphene congeners CHB-50 or 62 or (b) diets spiked with the combination of CHB N-Ary-Summation 50 + 62 and/or CHB N-Ary-Summation 40 + 41 + 44. In addition, seawater adapted Atlantic salmon smolts were fed technical toxaphene enriched feeds for 62 days. Zebrafish fed a diet containing CHB-50 and CHB-62 accumulated newly formed CHB-40 and 41 and CHB-44, respectively. The biomagnifications factors (BMF) of the toxaphene congeners in Atlantic salmon muscle from the feeds spiked with technical toxaphene were significantly correlated with their relative lipophilicity (expressed as log K{sub ow}). An exception was CHB-44 which had a higher BMF than could be expected from its specific log K{sub ow}, reflecting that CHB-44 is a metabolite formed under dietary exposure to CHB-62. This paper reports the in vivo dechlorination of nona-chlorinated toxaphene congeners into octa-chlorinated congeners in feeding trials with a model fish (zebrafish) and an oily food fish (Atlantic salmon).

  16. Characterization of behavioral and endocrine effects of LSD on zebrafish.

    Science.gov (United States)

    Grossman, Leah; Utterback, Eli; Stewart, Adam; Gaikwad, Siddharth; Chung, Kyung Min; Suciu, Christopher; Wong, Keith; Elegante, Marco; Elkhayat, Salem; Tan, Julia; Gilder, Thomas; Wu, Nadine; Dileo, John; Cachat, Jonathan; Kalueff, Allan V

    2010-12-25

    Lysergic acid diethylamide (LSD) is a potent hallucinogenic drug that strongly affects animal and human behavior. Although adult zebrafish (Danio rerio) are emerging as a promising neurobehavioral model, the effects of LSD on zebrafish have not been investigated previously. Several behavioral paradigms (the novel tank, observation cylinder, light-dark box, open field, T-maze, social preference and shoaling tests), as well as modern video-tracking tools and whole-body cortisol assay were used to characterize the effects of acute LSD in zebrafish. While lower doses (5-100 microg/L) did not affect zebrafish behavior, 250 microg/L LSD increased top dwelling and reduced freezing in the novel tank and observation cylinder tests, also affecting spatiotemporal patterns of activity (as assessed by 3D reconstruction of zebrafish traces and ethograms). LSD evoked mild thigmotaxis in the open field test, increased light behavior in the light-dark test, reduced the number of arm entries and freezing in the T-maze and social preference test, without affecting social preference. In contrast, LSD affected zebrafish shoaling (increasing the inter-fish distance in a group), and elevated whole-body cortisol levels. Overall, our findings show sensitivity of zebrafish to LSD action, and support the use of zebrafish models to study hallucinogenic drugs of abuse.

  17. Reducing the noise in behavioral assays: sex and age in adult zebrafish locomotion.

    Science.gov (United States)

    Philpott, Catelyn; Donack, Corey J; Cousin, Margot A; Pierret, Chris

    2012-12-01

    Many assays are used in animal model systems to measure specific human disease-related behaviors. The use of both adult and larval zebrafish as a behavioral model is gaining popularity. As this work progresses and potentially translates into new treatments, we must do our best to improve the sensitivity of these assays by reducing confounding factors. Scientists who use the mouse model system have demonstrated that sex and age can influence a number of behaviors. As a community, they have moved to report the age and sex of all animals used in their studies. Zebrafish work does not yet carry the same mandate. In this study, we evaluated sex and age differences in locomotion behavior. We found that age was a significant factor in locomotion, as was sex within a given age group. In short, as zebrafish age, they appear to show less base level locomotion. With regard to sex, younger (10 months) zebrafish showed more locomotion in males, while older zebrafish (22 months) showed more movement in females. These findings have led us to suggest that those using the zebrafish for behavioral studies control for age and sex within their experimental design and report these descriptors in their methods.

  18. Developmental exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin alters DNA methyltransferase (dnmt) expression in zebrafish (Danio rerio)

    International Nuclear Information System (INIS)

    DNA methylation is one of the most important epigenetic modifications involved in the regulation of gene expression. The DNA methylation reaction is catalyzed by DNA methyltransferases (DNMTs). Recent studies have demonstrated that toxicants can affect normal development by altering DNA methylation patterns, but the mechanisms of action are poorly understood. Hence, we tested the hypothesis that developmental exposure to TCDD affects dnmt gene expression patterns. Zebrafish embryos were exposed to 5 nM TCDD for 1 h from 4 to 5 h post-fertilization (hpf) and sampled at 12, 24, 48, 72, and 96 hpf to determine dnmt gene expression and DNA methylation patterns. We performed a detailed analysis of zebrafish dnmt gene expression during development and in adult tissues. Our results demonstrate that dnmt3b genes are highly expressed in early stages of development, and dnmt3a genes are more abundant in later stages. TCDD exposure upregulated dnmt1 and dnmt3b2 expression, whereas dnmt3a1, 3b1, and 3b4 are downregulated following exposure. We did not observe any TCDD-induced differences in global methylation or hydroxymethylation levels, but the promoter methylation of aryl hydrocarbon receptor (AHR) target genes was altered. In TCDD-exposed embryos, AHR repressor a (ahrra) and c-fos promoters were differentially methylated. To characterize the TCDD effects on DNMTs, we cloned the dnmt promoters with xenobiotic response elements and conducted AHR transactivation assays using a luciferase reporter system. Our results suggest that ahr2 can regulate dnmt3a1, dnmt3a2, and dnmt3b2 expression. Overall, we demonstrate that developmental exposure to TCDD alters dnmt expression and DNA methylation patterns. - Highlights: • TCDD altered the dnmt expression in a gene and developmental time-specific manner. • TCDD hypermethylated ahrra and hypomethylated c-fos proximal promoter regions. • Functional analysis suggests that ahr2 can regulate dnmt3a1, 3a2, and 3b2 expression. • Dnmt

  19. Developmental exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin alters DNA methyltransferase (dnmt) expression in zebrafish (Danio rerio)

    Energy Technology Data Exchange (ETDEWEB)

    Aluru, Neelakanteswar, E-mail: naluru@whoi.edu [Biology Department and Woods Hole Center for Oceans and Human Health, Woods Hole Oceanographic Institution, Woods Hole, MA 02543 (United States); Kuo, Elaine [Biology Department and Woods Hole Center for Oceans and Human Health, Woods Hole Oceanographic Institution, Woods Hole, MA 02543 (United States); Stanford University, 450 Serra Mall, Stanford, CA 94305 (United States); Helfrich, Lily W. [Biology Department and Woods Hole Center for Oceans and Human Health, Woods Hole Oceanographic Institution, Woods Hole, MA 02543 (United States); Northwestern University, 633 Clark St, Evanston, IL 60208 (United States); Karchner, Sibel I. [Biology Department and Woods Hole Center for Oceans and Human Health, Woods Hole Oceanographic Institution, Woods Hole, MA 02543 (United States); Linney, Elwood A. [Department of Molecular Genetics and Microbiology, Duke University Medical Center, Box 3020, Durham, NC 27710 (United States); Pais, June E. [New England Biolabs, 240 County Road, Ipswich, MA 01938 (United States); Franks, Diana G. [Biology Department and Woods Hole Center for Oceans and Human Health, Woods Hole Oceanographic Institution, Woods Hole, MA 02543 (United States)

    2015-04-15

    DNA methylation is one of the most important epigenetic modifications involved in the regulation of gene expression. The DNA methylation reaction is catalyzed by DNA methyltransferases (DNMTs). Recent studies have demonstrated that toxicants can affect normal development by altering DNA methylation patterns, but the mechanisms of action are poorly understood. Hence, we tested the hypothesis that developmental exposure to TCDD affects dnmt gene expression patterns. Zebrafish embryos were exposed to 5 nM TCDD for 1 h from 4 to 5 h post-fertilization (hpf) and sampled at 12, 24, 48, 72, and 96 hpf to determine dnmt gene expression and DNA methylation patterns. We performed a detailed analysis of zebrafish dnmt gene expression during development and in adult tissues. Our results demonstrate that dnmt3b genes are highly expressed in early stages of development, and dnmt3a genes are more abundant in later stages. TCDD exposure upregulated dnmt1 and dnmt3b2 expression, whereas dnmt3a1, 3b1, and 3b4 are downregulated following exposure. We did not observe any TCDD-induced differences in global methylation or hydroxymethylation levels, but the promoter methylation of aryl hydrocarbon receptor (AHR) target genes was altered. In TCDD-exposed embryos, AHR repressor a (ahrra) and c-fos promoters were differentially methylated. To characterize the TCDD effects on DNMTs, we cloned the dnmt promoters with xenobiotic response elements and conducted AHR transactivation assays using a luciferase reporter system. Our results suggest that ahr2 can regulate dnmt3a1, dnmt3a2, and dnmt3b2 expression. Overall, we demonstrate that developmental exposure to TCDD alters dnmt expression and DNA methylation patterns. - Highlights: • TCDD altered the dnmt expression in a gene and developmental time-specific manner. • TCDD hypermethylated ahrra and hypomethylated c-fos proximal promoter regions. • Functional analysis suggests that ahr2 can regulate dnmt3a1, 3a2, and 3b2 expression. • Dnmt

  20. Effects of azocyclotin on gene transcription and steroid metabolome of hypothalamic-pituitary-gonad axis, and their consequences on reproduction in zebrafish (Danio rerio).

    Science.gov (United States)

    Ma, You-Ning; Cao, Chu-Yan; Wang, Qiang-Wei; Gui, Wen-Jun; Zhu, Guo-Nian

    2016-10-01

    The widely used organotins have the potential to disrupt the endocrine system, but little is known of underlying mechanisms of azocyclotin toxicity in fish. The objective of the present study was to investigate the impact of azocyclotin on reproduction in zebrafish. Adult zebrafish were exposed to 0.09 and 0.45μg/L azocyclotin for 21days, and effects on steroid hormones and mRNA expression of the genes belonging to the hypothalamic-pituitary-gonad (HPG) axis were investigated. Mass spectrometry methodology was developed to profile steroids within the metabolome of the gonads. They were disrupted as a result of azocyclotin exposure. Alterations in the expression of key genes associated with reproductive endocrine pathways in the pituitary (lhβ), gonad (cyp19a1a, cyp17a1 and 17β-hsd3), and liver (vtg1, vtg2, cyp1a1, comt, ugt1a and gstp1) were correlated with significant reductions in estrogen in both sexes and increased testosterone in females. Azocyclotin-induced down-regulation of cyp19a1a in males suggested a reduction in the rate of estrogen biosynthesis, while up-regulation of hepatic cyp1a1 and comt in both sexes suggested an increase in estrogen biotransformation and clearance. Azocyclotin also induced change in the expression of 17β-hsd3, suggesting increased bioavailability of 11-ketotestosterone (11-KT) in the blood. Furthermore, the down-regulation of lhβ expression in the brains of azocyclotin-exposed fish was associated with inhibition of oocyte maturation in females and retarded spermatogenesis in males. As a histological finding, retarded development of the ovaries was found to be an important cause for decreased fecundity, with down-regulation of vtg suspected to be a likely underlying mechanism. Additionally, relatively high concentrations of azocyclotin in the gonads may have directly caused toxicity, thereby impairing gametogenesis and reproduction. Embryonic or larval abnormalities occurred in the F1 generation along with accumulated burdens

  1. PROFILING OF TS GENE EXPRESSION OF ZEBRAFISH DANIO RERIO EMBRYOGENESIS USING WHOLE MOUNT IN SITU HYBRIDIZATION%整体原位杂交法研究斑马鱼(Danio rerio)胚胎发育过程中胸苷酸合成酶(TS)的表达

    Institute of Scientific and Technical Information of China (English)

    牛荣丽; 梁丽英

    2011-01-01

    收集不同发育时期的斑马鱼胚胎,制备DIG标记的TS反义RNA探针,采用整体原位杂交方法研究胸苷酸合成酶(TS)基因在斑马鱼胚胎发育各期的时空表达状况.结果表明,在所取样的各个阶段,TS基因均有转录,但其部位不同,中囊胚过渡前后mRNA显现的部位仅存在于受精卵的动物极,10hpf时存在于整个胚胎的外围,至24hpf后集中到头部及其躯干部.112hpf在心脏部位强表达,其余部位表达相对较弱.%To analyze the expression pattern of thymidylate synthase (TS) of zebrafish Danio rerio embryogenesis, we collected zebrafish embryos at different phases and prepared TS digoxin-labeled RNA probe using whole mount in situ hybridization. We found that TS expression appeared at early zygote period, continued throughout the entire embryogenesis periods. Expression of TS was also discovered in different parts of the embryo: in the animal pole of the middle gastrula, the margin of whole embryo after 10 hours, in the head and somite after 24 hours post fertilization. After 112 hours post-fertilization, strong TS expression only in the heart. Therefore, TS plays important role in the regulation of zebrafish embryonic development.

  2. Nonhatching Decapsulated Artemia Cysts As a Replacement to Artemia Nauplii in Juvenile and Adult Zebrafish Culture.

    Science.gov (United States)

    Tye, Marc; Rider, Dana; Duffy, Elizabeth A; Seubert, Adam; Lothert, Brogen; Schimmenti, Lisa A

    2015-12-01

    Feeding Artemia nauplii as the main nutrition source for zebrafish is a common practice for many research facilities. Culturing live feed can be time-consuming and requires additional equipment to be purchased, maintained, and cleaned. Nonhatching decapsulated Artemia cysts (decaps) are a commercially available product that can be fed directly to fish. Several other ornamental fish species have been successfully cultured using decaps. Replacing Artemia nauplii with decaps could reduce the overall time and costs associated with the operation of a zebrafish facility. The objective of this study was to determine if decaps could be a suitable replacement to Artemia nauplii in juvenile and adult zebrafish culture. Wild-type zebrafish were fed one of three dietary treatments: decaps only, nauplii only, or a standard consisting of nauplii plus a commercially prepared pellet food. Survival, growth (length and weight), and embryo production were analyzed between the treatments. Fish receiving the decap diet demonstrated a significantly higher growth and embryo production when compared to the fish receiving the nauplii-only diet. When comparing the decap fish to the standard fish, no significant difference was found in mean survival, mean weight at 90 days postfertilization, or mean embryo production. It was determined that nonhatching decapsulated Artemia cysts can be used as a suitable replacement to Artemia nauplii in juvenile and adult zebrafish culture.

  3. Nonhatching Decapsulated Artemia Cysts As a Replacement to Artemia Nauplii in Juvenile and Adult Zebrafish Culture.

    Science.gov (United States)

    Tye, Marc; Rider, Dana; Duffy, Elizabeth A; Seubert, Adam; Lothert, Brogen; Schimmenti, Lisa A

    2015-12-01

    Feeding Artemia nauplii as the main nutrition source for zebrafish is a common practice for many research facilities. Culturing live feed can be time-consuming and requires additional equipment to be purchased, maintained, and cleaned. Nonhatching decapsulated Artemia cysts (decaps) are a commercially available product that can be fed directly to fish. Several other ornamental fish species have been successfully cultured using decaps. Replacing Artemia nauplii with decaps could reduce the overall time and costs associated with the operation of a zebrafish facility. The objective of this study was to determine if decaps could be a suitable replacement to Artemia nauplii in juvenile and adult zebrafish culture. Wild-type zebrafish were fed one of three dietary treatments: decaps only, nauplii only, or a standard consisting of nauplii plus a commercially prepared pellet food. Survival, growth (length and weight), and embryo production were analyzed between the treatments. Fish receiving the decap diet demonstrated a significantly higher growth and embryo production when compared to the fish receiving the nauplii-only diet. When comparing the decap fish to the standard fish, no significant difference was found in mean survival, mean weight at 90 days postfertilization, or mean embryo production. It was determined that nonhatching decapsulated Artemia cysts can be used as a suitable replacement to Artemia nauplii in juvenile and adult zebrafish culture. PMID:25495227

  4. Normal anatomy and histology of the adult zebrafish

    NARCIS (Netherlands)

    Menke, H.; Spitsbergen, J.M.; Wolterbeek, A.P.; Woutersen, R.A.

    2011-01-01

    The zebrafish has been shown to be an excellent vertebrate model for studying the roles of specific genes and signaling pathways. The sequencing of its genome and the relative ease with which gene modifications can be performed have led to the creation of numerous human disease models that can be us

  5. Intestinal upregulation of melanin-concentrating hormone in TNBS-induced enterocolitis in adult zebrafish.

    Directory of Open Access Journals (Sweden)

    Brenda M Geiger

    Full Text Available BACKGROUND: Melanin-concentrating hormone (MCH, an evolutionarily conserved appetite-regulating neuropeptide, has been recently implicated in the pathogenesis of inflammatory bowel disease (IBD. Expression of MCH is upregulated in inflamed intestinal mucosa in humans with colitis and MCH-deficient mice treated with trinitrobenzene-sulfonic acid (TNBS develop an attenuated form of colitis compared to wild type animals. Zebrafish have emerged as a new animal model of IBD, although the majority of the reported studies concern zebrafish larvae. Regulation MCH expression in the adult zebrafish intestine remains unknown. METHODS: In the present study we induced enterocolitis in adult zebrafish by intrarectal administration of TNBS. Follow-up included survival analysis, histological assessment of changes in intestinal architecture, and assessment of intestinal infiltration by myeloperoxidase positive cells and cytokine transcript levels. RESULTS: Treatment with TNBS dose-dependently reduced fish survival. This response required the presence of an intact microbiome, since fish pre-treated with vancomycin developed less severe enterocolitis. At 6 hours post-challenge, we detected a significant influx of myeloperoxidase positive cells in the intestine and upregulation of both proinflammatory and anti-inflammatory cytokines. Most importantly, and in analogy to human IBD and TNBS-induced mouse experimental colitis, we found increased intestinal expression of MCH and its receptor in TNBS-treated zebrafish. CONCLUSIONS: Taken together these findings not only establish a model of chemically-induced experimental enterocolitis in adult zebrafish, but point to effects of MCH in intestinal inflammation that are conserved across species.

  6. 氯化石蜡急性暴露对斑马鱼胚胎发育的毒性效应%Toxicity effects on zebrafish(Danio rerio) larvae following embryonic acute exposure to chlorinated paraffins

    Institute of Scientific and Technical Information of China (English)

    高永飞; 李佳; 李俊峰; 袁博; 张捷; 王亚韡; 梁勇

    2013-01-01

    This paper compares the effects of eight commercial chlorinated paraffins ( CPs ) on early embryonic development of zebrafish( Danio rerio) following embryonic acute exposure. The results showed that after 7 days exposure, CPs did not lead to embryonic mortality at the concentration of 1, 5, 10, 20 mg·L-1 . Meanwhile, no significant effects were observed on hatching rate among all groups, while gas bladders deformity was observed in zebrafish larvae exposed with some of the chlorinated paraffins. As the concentration of the CPs increased, deformity rate of gas bladders of zebrafish larvae raised, with an obvious dose-response correlation. Besides, four non-chlorinated short chain paraffins(C10-13) had no obvious toxicity on zebrafish embryonic development. These data indicated that CPs could cause deformity on the development of gas bladders of zebrafish larvae. However, the deformity effect on larvae had no relevance with either the chlorine content or the percentage of non-chlorinated short-chain paraffins in CPs. The potential toxicity of CPs on early embryonic development of fish needs further attention.%比较研究了8种商品化氯化石蜡( CPs)急性暴露对斑马鱼( Danio rerio)胚胎早期发育的影响。实验结果表明,浓度分别为1、5、10和20 mg·L-1的CPs暴露7 d后均不会造成斑马鱼胚胎死亡,对斑马鱼胚胎的孵化率也无明显影响,但部分商品化CPs暴露对斑马鱼幼鱼鱼鳔发育具有明显的致畸效应,且随着暴露浓度的升高,鱼鳔畸形率显著上升,存在着明显的剂量-效应关系;此外,4种未氯化的短链石蜡烃( C10-C13)暴露对斑马鱼胚胎发育没有明显的毒性。上述研究结果表明,CPs急性暴露可造成斑马鱼幼鱼鱼鳔发育畸形,而这种致畸效应与CPs的含氯量不相关,与CPs中未经氯化的短链石蜡烃也无相关性,CPs对鱼类胚胎早期发育的潜在毒性效应需要进一步关注。

  7. Morphological and molecular evidence for functional organization along the rostrocaudal axis of the adult zebrafish intestine

    Directory of Open Access Journals (Sweden)

    Lam Siew

    2010-06-01

    Full Text Available Abstract Background The zebrafish intestine is a simple tapered tube that is folded into three sections. However, whether the intestine is functionally similar along its length remains unknown. Thus, a systematic structural and functional characterization of the zebrafish intestine is desirable for future studies of the digestive tract and the intestinal biology and development. Results To characterize the structure and function of the adult zebrafish intestine, we divided the intestine into seven roughly equal-length segments, S1-S7, and systematically examined the morphology of the mucosal lining, histology of the epithelium, and molecular signatures from transcriptome analysis. Prominent morphological features are circumferentially-oriented villar ridges in segments S1-S6 and the absence of crypts. Molecular characterization of the transcriptome from each segment shows that segments S1-S5 are very similar while S6 and S7 unique. Gene ontology analyses reveal that S1-S5 express genes whose functions involve metabolism of carbohydrates, transport of lipids and energy generation, while the last two segments display relatively limited function. Based on comparative Gene Set Enrichment Analysis, the first five segments share strong similarity with human and mouse small intestine while S6 shows similarity with human cecum and rectum, and S7 with human rectum. The intestinal tract does not display the anatomical, morphological, and molecular signatures of a stomach and thus we conclude that this organ is absent from the zebrafish digestive system. Conclusions Our genome-wide gene expression data indicate that, despite the lack of crypts, the rostral, mid, and caudal portions of the zebrafish intestine have distinct functions analogous to the mammalian small and large intestine, respectively. Organization of ridge structures represents a unique feature of zebrafish intestine, though they produce similar cross sections to mammalian intestines

  8. Danio rerio: the Janus of the bone from embryo to scale

    Science.gov (United States)

    Mariotti, Massimo; Carnovali, Marta; Banfi, Giuseppe

    2015-01-01

    Summary Danio rerio (zebrafish), like the Roman god Janus, is an old animal model which is recently emerged and looks to the future with an increasing scientific success. Unlike other traditional animal models, zebrafish represents a versatile way to approach the study of the skeleton. Transparency of the larval stage, genetic manipulability and unique anatomical structures (scales) makes zebrafish a powerful and versatile instrument to investigate the bone tissue in terms of structure and function. Like Janus, zebrafish offers two different faces, or better, two models in one animal: larval and adult stage. The embryo can be used to isolate new genes involved in osteogenesis by large-scale mutagenesis screenings. The behavior of bone cells and genes in osteogenesis can be investigate by using transgenic lines, vital dyes, mutants and traditional molecular biology techniques. The adult zebrafish represents an important resource to study the pathways related to the bone metabolism and turnover. In particular, the properties of the caudal fin allow to study mechanisms of bone regeneration and reparation whereas the elasmoid scale represents an unique tool to investigate the bone metabolism under physiological or pathological conditions. PMID:26604948

  9. Zebrafish adult-derived hypothalamic neurospheres generate gonadotropin-releasing hormone (GnRH neurons

    Directory of Open Access Journals (Sweden)

    Christian Cortés-Campos

    2015-09-01

    Full Text Available Gonadotropin-releasing hormone (GnRH is a hypothalamic decapeptide essential for fertility in vertebrates. Human male patients lacking GnRH and treated with hormone therapy can remain fertile after cessation of treatment suggesting that new GnRH neurons can be generated during adult life. We used zebrafish to investigate the neurogenic potential of the adult hypothalamus. Previously we have characterized the development of GnRH cells in the zebrafish linking genetic pathways to the differentiation of neuromodulatory and endocrine GnRH cells in specific regions of the brain. Here, we developed a new method to obtain neural progenitors from the adult hypothalamus in vitro. Using this system, we show that neurospheres derived from the adult hypothalamus can be maintained in culture and subsequently differentiate glia and neurons. Importantly, the adult derived progenitors differentiate into neurons containing GnRH and the number of cells is increased through exposure to either testosterone or GnRH, hormones used in therapeutic treatment in humans. Finally, we show in vivo that a neurogenic niche in the hypothalamus contains GnRH positive neurons. Thus, we demonstrated for the first time that neurospheres can be derived from the hypothalamus of the adult zebrafish and that these neural progenitors are capable of producing GnRH containing neurons.

  10. Zebrafish adult-derived hypothalamic neurospheres generate gonadotropin-releasing hormone (GnRH) neurons

    Science.gov (United States)

    Cortés-Campos, Christian; Letelier, Joaquín; Ceriani, Ricardo; Whitlock, Kathleen E.

    2015-01-01

    ABSTRACT Gonadotropin-releasing hormone (GnRH) is a hypothalamic decapeptide essential for fertility in vertebrates. Human male patients lacking GnRH and treated with hormone therapy can remain fertile after cessation of treatment suggesting that new GnRH neurons can be generated during adult life. We used zebrafish to investigate the neurogenic potential of the adult hypothalamus. Previously we have characterized the development of GnRH cells in the zebrafish linking genetic pathways to the differentiation of neuromodulatory and endocrine GnRH cells in specific regions of the brain. Here, we developed a new method to obtain neural progenitors from the adult hypothalamus in vitro. Using this system, we show that neurospheres derived from the adult hypothalamus can be maintained in culture and subsequently differentiate glia and neurons. Importantly, the adult derived progenitors differentiate into neurons containing GnRH and the number of cells is increased through exposure to either testosterone or GnRH, hormones used in therapeutic treatment in humans. Finally, we show in vivo that a neurogenic niche in the hypothalamus contains GnRH positive neurons. Thus, we demonstrated for the first time that neurospheres can be derived from the hypothalamus of the adult zebrafish and that these neural progenitors are capable of producing GnRH containing neurons. PMID:26209533

  11. Treatment of Glucocorticoids Inhibited Early Immune Responses and Impaired Cardiac Repair in Adult Zebrafish.

    Directory of Open Access Journals (Sweden)

    Wei-Chang Huang

    Full Text Available Myocardial injury, such as myocardial infarction (MI, can lead to drastic heart damage. Zebrafish have the extraordinary ability to regenerate their heart after a severe injury. Upon ventricle resection, fibrin clots seal the wound and serve as a matrix for recruiting myeloid-derived phagocytes. Accumulated neutrophils and macrophages not only reduce the risk of infection but also secrete cytokines and growth factors to promote tissue repair. However, the underlying cellular and molecular mechanisms for how immune responses are regulated during the early stages of cardiac repair are still unclear. We investigated the role and programming of early immune responses during zebrafish heart regeneration. We found that zebrafish treated with an anti-inflammatory glucocorticoid had significantly reduced heart regenerative capacities, consistent with findings in other higher vertebrates. Moreover, inhibiting the inflammatory response led to excessive collagen deposition. A microarray approach was used to assess the differential expression profiles between zebrafish hearts with normal or impaired healing. Combining cytokine profiling and immune-staining, our data revealed that impaired heart regeneration could be due to reduced phagocyte recruitment, leading to diminished angiogenesis and cell proliferation post-cardiac injury. Despite their robust regenerative ability, our study revealed that glucocorticoid treatment could effectively hinder cardiac repair in adult zebrafish by interfering with the inflammatory response. Our findings may help to clarify the initiation of cardiac repair, which could be used to develop a therapeutic intervention that may enhance cardiac repair in humans to compensate for the loss of cardiomyocytes after an MI.

  12. Regeneration, Plasticity, and Induced Molecular Programs in Adult Zebrafish Brain

    OpenAIRE

    Mehmet Ilyas Cosacak; Christos Papadimitriou; Caghan Kizil

    2015-01-01

    Regenerative capacity of the brain is a variable trait within animals. Aquatic vertebrates such as zebrafish have widespread ability to renew their brains upon damage, while mammals have—if not none—very limited overall regenerative competence. Underlying cause of such a disparity is not fully evident; however, one of the reasons could be activation of peculiar molecular programs, which might have specific roles after injury or damage, by the organisms that regenerate. If this hypothesis is c...

  13. Stable multilineage xenogeneic replacement of definitive hematopoiesis in adult zebrafish

    OpenAIRE

    Isabell Hess; Thomas Boehm

    2016-01-01

    Bony fishes are the most numerous and phenotypically diverse group of vertebrates inhabiting our planet, making them an ideal target for identifying general principles of tissue development and function. However, lack of suitable experimental platforms prevents the exploitation of this rich source of natural phenotypic variation. Here, we use a zebrafish strain lacking definitive hematopoiesis for interspecific analysis of hematopoietic cell development. Without conditioning prior to transpla...

  14. Cadmium(Cd)-induced oxidative stress down-regulates the gene expression of DNA mismatch recognition proteins MutS homolog 2 (MSH2) and MSH6 in zebrafish (Danio rerio) embryos

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, Todd, E-mail: toddhsu@mail.ntou.edu.tw [Institute of Bioscience and Biotechnology and Center of Excellence for Marine Bioenvironment and Biotechnology, National Taiwan Ocean University, Keelung 20224, Taiwan (China); Huang, Kuan-Ming; Tsai, Huei-Ting; Sung, Shih-Tsung; Ho, Tsung-Nan [Institute of Bioscience and Biotechnology and Center of Excellence for Marine Bioenvironment and Biotechnology, National Taiwan Ocean University, Keelung 20224, Taiwan (China)

    2013-01-15

    DNA mismatch repair (MMR) of simple base mismatches and small insertion-deletion loops in eukaryotes is initiated by the binding of the MutS homolog 2 (MSH2)-MSH6 heterodimer to mismatched DNA. Cadmium (Cd) is a genotoxic heavy metal that has been recognized as a human carcinogen. Oxidant stress and inhibition of DNA repair have been proposed as major factors underlying Cd genotoxicity. Our previous studies indicated the ability of Cd to disturb the gene expression of MSH6 in zebrafish (Danio rerio) embryos. This study was undertaken to explore if Cd-induced oxidative stress down-regulated MSH gene activities. Following the exposure of zebrafish embryos at 1 h post fertilization (hpf) to sublethal concentrations of Cd at 3-5 {mu}M for 4 or 9 h, a parallel down-regulation of MSH2, MSH6 and Cu/Zn superoxide dismutase (Cu/Zn-SOD) gene expression was detected by real-time RT-PCR and the expression levels were 40-50% of control after a 9-h exposure. Cd exposure also induced oxidative stress, yet no inhibition of catalase gene activity was observed. Whole mount in situ hybridization revealed a wide distribution of msh6 mRNA in the head regions of 10 hpf embryos and pretreatment of embryos with antioxidants butylhydroxytoluene (BHT), D-mannitol or N-acetylcysteine (NAC) at 1-10 {mu}M restored Cd-suppressed msh6 expression. QPCR confirmed the protective effects of antioxidants on Cd-suppressed msh2/msh6 mRNA production. Down-regulated MSH gene activities reaching about 50% of control were also induced in embryos exposed to paraquat, a reactive oxygen species (ROS)-generating herbicide, or hydrogen peroxide at 200 {mu}M. Hence, Cd at sublethal levels down-regulates msh2/msh6 expression primarily via ROS as signaling molecules. The transcriptional activation of human msh6 is known to be fully dependent on the specificity factor 1 (Sp1). Cd failed to inhibit the DNA binding activity of zebrafish Sp1 unless at lethal concentrations based on band shift assay, therefore

  15. F-spondin/spon1b expression patterns in developing and adult zebrafish.

    Directory of Open Access Journals (Sweden)

    Veronica Akle

    Full Text Available F-spondin, an extracellular matrix protein, is an important player in embryonic morphogenesis and CNS development, but its presence and role later in life remains largely unknown. We generated a transgenic zebrafish in which GFP is expressed under the control of the F-spondin (spon1b promoter, and used it in combination with complementary techniques to undertake a detailed characterization of the expression patterns of F-spondin in developing and adult brain and periphery. We found that F-spondin is often associated with structures forming long neuronal tracts, including retinal ganglion cells, the olfactory bulb, the habenula, and the nucleus of the medial longitudinal fasciculus (nMLF. F-spondin expression coincides with zones of adult neurogenesis and is abundant in CSF-contacting secretory neurons, especially those in the hypothalamus. Use of this new transgenic model also revealed F-spondin expression patterns in the peripheral CNS, notably in enteric neurons, and in peripheral tissues involved in active patterning or proliferation in adults, including the endoskeleton of zebrafish fins and the continuously regenerating pharyngeal teeth. Moreover, patterning of the regenerating caudal fin following fin amputation in adult zebrafish was associated with F-spondin expression in the blastema, a proliferative region critical for tissue reconstitution. Together, these findings suggest major roles for F-spondin in the CNS and periphery of the developing and adult vertebrate.

  16. Characterization, cDNA cloning and expression pattern of relaxin gene during embryogenesis of Danio rerio.

    Science.gov (United States)

    Fiengo, Marcella; Donizetti, Aldo; del Gaudio, Rosanna; Minucci, Sergio; Aniello, Francesco

    2012-06-01

    We report the identification, the cDNA cloning, the temporal and spatial expression pattern analysis of the rln gene in the zebrafish Danio rerio. The deduced Rln B and A domains show different evolutionary conservation. Rln B domain shows higher similarity when compared to zebrafish and human RLN3 B domain than human RLN1 and RLN2 B domain. Differently, the zebrafish Rln A domain shows relatively low amino acid sequence similarity when compared with the same sequences. The rln gene is transcribed both during embryogenesis and in adult organism, where higher transcript level has been particularly evidenced in the brain. Moreover, we provide the first description of rln spatial expression pattern during embryonic development. In particular, we show restricted transcript localization starting at the pharyngula stage in olfactory placode, branchial arch region, and in a cell cluster near to otic vesicle. In larval stage, new transcription territories have been detected in both neural and non-neural regions. In particular, in the brain, rln expression has been revealed in telencephalic region around anterior commissure, in the preoptic area, and in restricted rombencephalic cell clusters. Expression of rln gene in extra-neural territories has been detected in the pancreatic and thyroid gland regions. Danio rerio rln expression pattern analysis reveals shared features with the mammalian RLN gene, particularly in the brain, where it might have a role in the neurophysiological processes. In addition, expression in the thyroid and pancreas region suggests a function as a paracrine and endocrine hormone.

  17. Developmental lead acetate exposure induces embryonic toxicity and memory deficit in adult zebrafish.

    Science.gov (United States)

    Chen, Jiangfei; Chen, Yuanhong; Liu, Wei; Bai, Chenglian; Liu, Xuexia; Liu, Kai; Li, Rong; Zhu, Jian-Hong; Huang, Changjiang

    2012-01-01

    Lead is a persistent metal and commonly present in our living environment. The present study was aimed to investigate lead-induced embryonic toxicity, behavioral responses, and adult learning/memory deficit in zebrafish. Lead acetate (PbAc) induced malformations such as uninflated swim bladder, bent spine and yolk-sac edema with an EC₅₀ of 0.29 mg/L at 120 h post fertilization (hpf). Spontaneous movement as characterized by tail bend frequency was significantly altered in zebrafish embryos following exposure to PbAc. Behavior assessment demonstrated that lead exposure changed behavioral responses in zebrafish larvae, as hyperactivity was detected within the first minute of light-to-dark transition in the fish exposed to PbAc from 6 to 96 hpf, and a different dose-dependent change was found in swimming speeds in the dark and in the light at 120 hpf following lead exposure. Learning/memory task assay showed that embryos exposed to PbAc from 6 to 120 hpf developed learning/memory deficit at adulthood as exhibited by a significant decrease in accuracy rate to find the food and a significant increase in finding time. Overall, our results suggested that low dose of developmental lead exposure resulted in embryonic toxicity, behavioral alteration, and adult learning/memory deficit in zebrafish. PMID:22975620

  18. Swimming impairment and acetylcholinesterase inhibition in zebrafish exposed to copper or chlorpyrifos separately, or as mixtures

    OpenAIRE

    Tilton, Fred A.; Bammler, Theo K.; Gallagher, Evan P.

    2010-01-01

    Pesticides such as chlorpyrifos (CPF) and metals such as copper can impair swimming behavior in fish. However, the impact to swimming behavior from exposure to mixtures of neurotoxicants has received little attention. In the current study, we analyzed spontaneous swimming rates of adult zebrafish (Danio rerio) to investigate in vivo mixture interactions involving two chemical classes. Zebrafish were exposed to the neurotoxicants copper chloride (CuCl, 0.1 μM, 0.25 μM, 0.6 μM, or 6.3, 16, 40 p...

  19. Improvement of surface ECG recording in adult zebrafish reveals that the value of this model exceeds our expectation.

    Science.gov (United States)

    Liu, Chi Chi; Li, Li; Lam, Yun Wah; Siu, Chung Wah; Cheng, Shuk Han

    2016-01-01

    The adult zebrafish has been used to model the electrocardiogram (ECG) for human cardiovascular studies. Nonetheless huge variations are observed among studies probably because of the lack of a reliable and reproducible recording method. In our study, an adult zebrafish surface ECG recording technique was improved using a multi-electrode method and by pre-opening the pericardial sac. A convenient ECG data analysis method without wavelet transform was also established. Intraperitoneal injection of KCl in zebrafish induced an arrhythmia similar to that of humans, and the arrhythmia was partially rescued by calcium gluconate. Amputation and cryoinjury of the zebrafish heart induced ST segment depression and affected QRS duration after injury. Only cryoinjury decelerated the heart rate. Different changes were also observed in the QT interval during heart regeneration in these two injury models. We also characterized the electrocardiophysiology of breakdance zebrafish mutant with a prolonged QT interval, that has not been well described in previous studies. Our study provided a reliable and reproducible means to record zebrafish ECG and analyse data. The detailed characterization of the cardiac electrophysiology of zebrafish and its mutant revealed that the potential of the zebrafish in modeling the human cardiovascular system exceeds expectations. PMID:27125643

  20. 斑马鱼繁殖内分泌学研究进展%Advances in Research on Reproductive Endocrinology of Zebrafish (Danio rerio)

    Institute of Scientific and Technical Information of China (English)

    周玉国; 温海深

    2007-01-01

    作为四大模式动物之一,斑马鱼(Danio rerio)广泛应用于胚胎学、发育生物学、毒理学、分子生物学等研究.但关于斑马鱼繁殖内分泌生理和环境毒理方面的研究少见报道,本文综述了近年来,在内分泌学方面以斑马鱼作为实验动物的研究概况.

  1. Improving the production of transgenic fish germlines: in vivo evaluation of mosaicism in zebrafish (Danio rerio using a green fluorescent protein (GFP and growth hormone cDNA transgene co-injection strategy

    Directory of Open Access Journals (Sweden)

    Márcio de Azevedo Figueiredo

    2007-01-01

    Full Text Available In fish, microinjection is the method most frequently used for gene transfer. However, due to delayed transgene integration this technique almost invariably produces mosaic individuals and if the gene is not integrated into germ cells its transmission to descendants is difficult or impossible. We evaluated the degree of in vivo mosaicism using a strategy where a reporter transgene is co-injected with a transgene of interest so that potential germline founders can be easily identified. Transgenic zebrafish (Danio rerio were produced using two transgenes, both comprised of the carp beta-actin promoter driving the expression of either the green fluorescent protein (GFP reporter gene or the growth hormone cDNA from the marine silverside fish Odonthestes argentinensis. The methodology applied allowed a rapid identification of G0 transgenic fish and also detected which fish were transmitting transgenes to the next generation. This strategy also allowed inferences to be made about genomic transgene integration events in the six lineages produced and allowed the identification of one lineage transmitting both transgenes linked on the same chromosome. These results represent a significant advance in the reduction of the effort invested in producing a stable genetically modified fish lineage.

  2. Regeneration, Plasticity, and Induced Molecular Programs in Adult Zebrafish Brain

    Science.gov (United States)

    Cosacak, Mehmet Ilyas; Papadimitriou, Christos; Kizil, Caghan

    2015-01-01

    Regenerative capacity of the brain is a variable trait within animals. Aquatic vertebrates such as zebrafish have widespread ability to renew their brains upon damage, while mammals have—if not none—very limited overall regenerative competence. Underlying cause of such a disparity is not fully evident; however, one of the reasons could be activation of peculiar molecular programs, which might have specific roles after injury or damage, by the organisms that regenerate. If this hypothesis is correct, then there must be genes and pathways that (a) are expressed only after injury or damage in tissues, (b) are biologically and functionally relevant to restoration of neural tissue, and (c) are not detected in regenerating organisms. Presence of such programs might circumvent the initial detrimental effects of the damage and subsequently set up the stage for tissue redevelopment to take place by modulating the plasticity of the neural stem/progenitor cells. Additionally, if transferable, those “molecular mechanisms of regeneration” could open up new avenues for regenerative therapies of humans in clinical settings. This review focuses on the recent studies addressing injury/damage-induced molecular programs in zebrafish brain, underscoring the possibility of the presence of genes that could be used as biomarkers of neural plasticity and regeneration. PMID:26417601

  3. ZEBRAFISH CHROMOSOME-BANDING

    NARCIS (Netherlands)

    PIJNACKER, LP; FERWERDA, MA

    1995-01-01

    Banding techniques were carried out on metaphase chromosomes of zebrafish (Danio rerio) embryos. The karyotypes with the longest chromosomes consist of 12 metacentrics, 26 submetacentrics, and 12 subtelocentrics (2n = 50). All centromeres are C-band positive. Eight chromosomes have a pericentric C-b

  4. Time-Gated Optical Projection Tomography Allows Visualization of Adult Zebrafish Internal Structures

    Science.gov (United States)

    Foglia, Efrem Alessandro; Pistocchi, Anna; D'Andrea, Cosimo; Valentini, Gianluca; Cubeddu, Rinaldo; De Silvestri, Sandro; Cerullo, Giulio; Cotelli, Franco

    2012-01-01

    Optical imaging through biological samples is compromised by tissue scattering and currently various approaches aim to overcome this limitation. In this paper we demonstrate that an all optical technique, based on non-linear upconversion of infrared ultrashort laser pulses and on multiple view acquisition, allows the reduction of scattering effects in tomographic imaging. This technique, namely Time-Gated Optical Projection Tomography (TGOPT), is used to reconstruct three dimensionally the internal structure of adult zebrafish without staining or clearing agents. This method extends the use of Optical Projection Tomography to optically diffusive samples yielding reconstructions with reduced artifacts, increased contrast and improved resolution with respect to those obtained with non-gated techniques. The paper shows that TGOPT is particularly suited for imaging the skeletal system and nervous structures of adult zebrafish. PMID:23185643

  5. Global gene expression profile induced by the UV-filter 2-ethyl-hexyl-4-trimethoxycinnamate (EHMC) in zebrafish (Danio rerio)

    International Nuclear Information System (INIS)

    Residues of the UV-filter 2-ethyl-hexyl-4-trimethoxycinnamate (EHMC) are ubiquitously found in aquatic biota but potential adverse effects in fish are fairly unknown. To identify molecular effects and modes of action of EHMC we applied a gene expression profiling in zebrafish using whole genome microarrays. Transcriptome analysis and validation of targeted genes were performed after 14 days of exposure of male zebrafish. Concentrations of 2.2 μg/L and 890 μg/L EHMC lead to alteration of 1096 and 1137 transcripts, respectively, belonging to many pathways. Genes involved in lipid metabolism and estrogenic pathway (vtg1), lipid biosynthesis (ptgds), vitamin A metabolic process (rbp2a), DNA damage and apoptosis (gadd45b), and regulation of cell growth (igfbp1a) were investigated by qRT-PCR analysis in whole body, liver, brain and testis. The analysis showed tissue-specific gene profiles and revealed that EHMC slightly affects the transcription of genes involved in hormonal pathways including vtg1, esr1, esr2b, ar, cyp19b and hsd17β3. - Highlights: → The UV-filter EHMC accumulates in biota and shows expressional changes in fish. → Molecular effects of EHMC are demonstrated by microarrays and qRT-PCR in zebrafish. → Expressional changes in zebrafish occur at environmentally relevant concentrations. → The expressional changes point to interference of EHMC with the sex hormone system. → Additionally, many pathways are affected demonstrating multiple activities of EHMC. - Gene expression changes by 2-ethyl-hexyl-4-trimethoxycinnamate in zebrafish.

  6. Global gene expression profile induced by the UV-filter 2-ethyl-hexyl-4-trimethoxycinnamate (EHMC) in zebrafish (Danio rerio)

    Energy Technology Data Exchange (ETDEWEB)

    Zucchi, Sara [University of Applied Sciences Northwestern Switzerland, School of Life Sciences, Gruendensrasse 40, CH-4132 Muttenz (Switzerland); Oggier, Daniela M. [University of Applied Sciences Northwestern Switzerland, School of Life Sciences, Gruendensrasse 40, CH-4132 Muttenz (Switzerland); University of Zuerich, Institute of Plant Biology, Division of Limnology, 8802 Kilchberg (Switzerland); Fent, Karl, E-mail: karl.fent@fhnw.ch [University of Applied Sciences Northwestern Switzerland, School of Life Sciences, Gruendensrasse 40, CH-4132 Muttenz (Switzerland); Swiss Federal Institute of Technology Zuerich (ETH Zuerich), Department of Environmental Sciences, 8092 Zuerich (Switzerland)

    2011-10-15

    Residues of the UV-filter 2-ethyl-hexyl-4-trimethoxycinnamate (EHMC) are ubiquitously found in aquatic biota but potential adverse effects in fish are fairly unknown. To identify molecular effects and modes of action of EHMC we applied a gene expression profiling in zebrafish using whole genome microarrays. Transcriptome analysis and validation of targeted genes were performed after 14 days of exposure of male zebrafish. Concentrations of 2.2 {mu}g/L and 890 {mu}g/L EHMC lead to alteration of 1096 and 1137 transcripts, respectively, belonging to many pathways. Genes involved in lipid metabolism and estrogenic pathway (vtg1), lipid biosynthesis (ptgds), vitamin A metabolic process (rbp2a), DNA damage and apoptosis (gadd45b), and regulation of cell growth (igfbp1a) were investigated by qRT-PCR analysis in whole body, liver, brain and testis. The analysis showed tissue-specific gene profiles and revealed that EHMC slightly affects the transcription of genes involved in hormonal pathways including vtg1, esr1, esr2b, ar, cyp19b and hsd17{beta}3. - Highlights: > The UV-filter EHMC accumulates in biota and shows expressional changes in fish. > Molecular effects of EHMC are demonstrated by microarrays and qRT-PCR in zebrafish. > Expressional changes in zebrafish occur at environmentally relevant concentrations. > The expressional changes point to interference of EHMC with the sex hormone system. > Additionally, many pathways are affected demonstrating multiple activities of EHMC. - Gene expression changes by 2-ethyl-hexyl-4-trimethoxycinnamate in zebrafish.

  7. Knockdown of PU.1 mRNA and AS lncRNA regulates expression of immune-related genes in zebrafish Danio rerio.

    Science.gov (United States)

    Wei, Ning; Pang, Weijun; Wang, Yu; Xiong, Yan; Xu, Ruxiang; Wu, Wenjing; Zhao, Cunzhen; Yang, Gongshe

    2014-06-01

    The transcription factor PU.1 plays a key role in the development of immune system. Recent evidence demonstrated bidirectional transcription and a sense/antisense transcriptional regulatory manner in PU.1 locus. However, the effect of PU.1 mRNA and its antisense long non-coding RNA (AS lncRNA) on adaptive immunity in vivo is still not clear. In this study, we first confirmed the expression of PU.1 AS lncRNA by strand-specific RT-PCR in zebrafish. Additionally, we found that GFP was detected in zebrafish kidney using tissue smears after zebrafish was intraperitoneally injected with pLentiHI-PU.1 shRNA or pLentiHI-PU.1 AS shRNA for 2 days. Moreover, on day 0, 2 and 4, the levels of PU.1 and immune-related genes including TCRAC, Rag2, AID, IgLC-1, mIg, and sIg mRNAs were detected using real-time qPCR. The results showed that the levels of PU.1 and above 6 immune-related gene mRNAs were significantly downregulated on day 2 (PPU.1 shRNA, whereas these genes were markedly upregulated by the treatment with the pLentiHI-PU.1 AS shRNA. Based on our results, we suggested that the effects of PU.1 transcripts including mRNA and AS lncRNA on immune-related gene expression in zebrafish were opposite. To our knowledge, this was the first report that a novel functional AS lncRNA in adaptive immunity was transcribed from the zebrafish PU.1 locus. Our findings provided novel insight into further exploration on modulating adaptive immunity by regulating PU.1 mRNA and AS lncRNA.

  8. Effect of radiation dose-rate on hematopoietic cell engraftment in adult zebrafish.

    Directory of Open Access Journals (Sweden)

    Tiffany J Glass

    Full Text Available Although exceptionally high radiation dose-rates are currently attaining clinical feasibility, there have been relatively few studies reporting the biological consequences of these dose-rates in hematopoietic cell transplant (HCT. In zebrafish models of HCT, preconditioning before transplant is typically achieved through radiation alone. We report the comparison of outcomes in adult zebrafish irradiated with 20 Gy at either 25 or 800 cGy/min in the context of experimental HCT. In non-transplanted irradiated fish we observed no substantial differences between dose-rate groups as assessed by fish mortality, cell death in the kidney, endogenous hematopoietic reconstitution, or gene expression levels of p53 and ddb2 (damage-specific DNA binding protein 2 in the kidney. However, following HCT, recipients conditioned with the higher dose rate showed significantly improved donor-derived engraftment at 9 days post transplant (p ≤ 0.0001, and improved engraftment persisted at 31 days post transplant. Analysis for sdf-1a expression, as well as transplant of hematopoietic cells from cxcr4b -/- zebrafish, (odysseus, cumulatively suggest that the sdf-1a/cxcr4b axis is not required of donor-derived cells for the observed dose-rate effect on engraftment. Overall, the adult zebrafish model of HCT indicates that exceptionally high radiation dose-rates can impact HCT outcome, and offers a new system for radiobiological and mechanistic interrogation of this phenomenon. Key words: Radiation dose rate, Total Marrow Irradiation (TMI, Total body irradiation (TBI, SDF-1, Zebrafish, hematopoietic cell transplant.

  9. Zebrafish Development: High-throughput Test Systems to Assess Developmental Toxicity

    Science.gov (United States)

    Abstract Because of its developmental concordance, ease of handling and rapid development, the small teleost, zebrafish (Danio rerio), is frequently promoted as a vertebrate model for medium-throughput developmental screens. This present chapter discusses zebrafish as an altern...

  10. zebraflash transgenic lines for in vivo bioluminescence imaging of stem cells and regeneration in adult zebrafish

    OpenAIRE

    Chen, Chen-Hui; Durand, Ellen; Wang, Jinhu; Zon, Leonard I.; Poss, Kenneth D.

    2013-01-01

    The zebrafish has become a standard model system for stem cell and tissue regeneration research, based on powerful genetics, high tissue regenerative capacity and low maintenance costs. Yet, these studies can be challenged by current limitations of tissue visualization techniques in adult animals. Here we describe new imaging methodology and present several ubiquitous and tissue-specific luciferase-based transgenic lines, which we have termed zebraflash, that facilitate the assessment of rege...

  11. Efectos del ácido retinoico en el desarrollo temprano del pez cebra Danio rerio

    OpenAIRE

    Carreño Gutiérrez, Héctor

    2009-01-01

    [ES]Este trabajo trata sobre los efectos del ácido retinoico en el desarrollo temprano del pez cebra Danio rerio. [EN]This work deals with the effects of retinoic acid in the early development of zebrafish Danio rerio. Trabajo de Fin de Máster del Máster en Neurociencias, curso 2008-2009.

  12. Identification and characterization of the pumilio-2 expressed in zebrafish embryos and adult tissues.

    Science.gov (United States)

    Wang, Huan Nan; Xu, Yan; Tao, Ling Jie; Zhou, Jian; Qiu, Meng Xi; Teng, Yu Hang; Deng, Feng Jiao

    2012-03-01

    Pumilio proteins regulate the translation of specific proteins required for germ cell development and morphogenesis. In the present study, we have identified the pumilio-2 in zebrafish and analyze its expression in adult tissues and early embryos. Pumilio-2 codes for the full-length Pumilio-2 protein and contains a PUF-domain. When compared to the mammalian and avian Pumilio-2 proteins, zebrafish Pumilio-2 protein was found to contain an additional sequence of 24 amino acid residues within the PUF-domain. Zebrafish pumilio-2 mRNA is expressed in the ovary, testis, liver, kidney and brain but is absent in the heart and muscle as detected by RT-PCR. The results of in situ hybridization indicate that transcripts of pumilio-2 are distributed in all blastomeres from the 1-cell stage to the sphere stage and accumulate in the head and tail during the 60%-epiboly and 3-somite stages. Transcripts were also detected in the brain and neural tube of the 24 h post-fertilization (hpf) embryos. Western blot analyses indicate that the Pumilio-2 protein is strongly expressed in the ovary, testis and brain but not in other tissues. These data suggest that pumilio-2 plays an important role in the development of the zebrafish germ cells and nervous system.

  13. Differential requirement for irf8 in formation of embryonic and adult macrophages in zebrafish.

    Directory of Open Access Journals (Sweden)

    Celia E Shiau

    Full Text Available Interferon regulatory factor 8 (Irf8 is critical for mammalian macrophage development and innate immunity, but its role in teleost myelopoiesis remains incompletely understood. In particular, genetic tools to analyze the role of Irf8 in zebrafish macrophage development at larval and adult stages are lacking. We generated irf8 null mutants in zebrafish using TALEN-mediated targeting. Our analysis defines different requirements for irf8 at different stages. irf8 is required for formation of all macrophages during primitive and transient definitive hematopoiesis, but not during adult-phase definitive hematopoiesis starting at 5-6 days postfertilization. At early stages, irf8 mutants have excess neutrophils and excess cell death in pu.1-expressing myeloid cells. Macrophage fates were recovered in irf8 mutants after wildtype irf8 expression in neutrophil and macrophage lineages, suggesting that irf8 regulates macrophage specification and survival. In juvenile irf8 mutant fish, mature macrophages are present, but at numbers significantly reduced compared to wildtype, indicating an ongoing requirement for irf8 after embryogenesis. As development progresses, tissue macrophages become apparent in zebrafish irf8 mutants, with the possible exception of microglia. Our study defines distinct requirement for irf8 in myelopoiesis before and after transition to the adult hematopoietic system.

  14. EZR1: a novel family of highly expressed retroelements induced by TCDD and regulated by a NF-κB-like factor in embryos of zebrafish (Danio rerio).

    Science.gov (United States)

    Goldstone, Heather M H; Tokunaga, Saimi; Schlezinger, Jennifer J; Goldstone, Jared V; Stegeman, John J

    2012-03-01

    Transcript profiling using a zebrafish heart cDNA library previously revealed abundant expressed sequence tags (ESTs) upregulated in zebrafish embryos treated with the aryl hydrocarbon receptor (AHR) agonist 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Here, we identify those ESTs as LTR-containing retroelements termed EZR1 (Expressed-Zebrafish-Retroelement group 1). EZR1 is highly redundant in the genome and includes canonical long terminal repeats (LTRs) flanking an integrase-like open reading frame and a region similar to retroviral envelope protein genes. EZR1 sequences lack reverse transcriptase, RNase H, or protease, indicating retrotransposition would be nonautonomous. No AHR binding motifs were found in the EZR1 promoter region. A putative NF-κB-binding site was found, and TCDD-treated zebrafish embryos had significantly increased levels of nuclear protein(s) binding to this sequence. Protein-EZR1 DNA complex formation was partially competed by a mammalian consensus κB sequence, consistent with NF-κB-like activation contributing to increased protein binding to this site. Mobility of the TCDD-induced protein-EZR1 complex differed from that of authentic NF-κB protein bound to the consensus κB site. The results suggest that EZR1 is regulated by interaction with NF-κB or NF-κB-like protein(s) different from the NF-κB protein binding to the consensus κB site. The nature of the NF-κB-like protein and the relationship between EZR1 induction and cardiovascular toxicity caused by TCDD warrant further investigation.

  15. The Nicotine-Evoked Locomotor Response: A Behavioral Paradigm for Toxicity Screening in Zebrafish (Danio rerio Embryos and Eleutheroembryos Exposed to Methylmercury.

    Directory of Open Access Journals (Sweden)

    Francisco X Mora-Zamorano

    Full Text Available This study is an adaptation of the nicotine-evoked locomotor response (NLR assay, which was originally utilized for phenotype-based neurotoxicity screening in zebrafish embryos. Zebrafish embryos do not exhibit spontaneous swimming until roughly 4 days post-fertilization (dpf, however, a robust swimming response can be induced as early as 36 hours post-fertilization (hpf by means of acute nicotine exposure (30-240μM. Here, the NLR was tested as a tool for early detection of locomotor phenotypes in 36, 48 and 72 hpf mutant zebrafish embryos of the non-touch-responsive maco strain; this assay successfully discriminated mutant embryos from their non-mutant siblings. Then, methylmercury (MeHg was used as a proof-of-concept neurotoxicant to test the effectiveness of the NLR assay as a screening tool in toxicology. The locomotor effects of MeHg were evaluated in 6 dpf wild type eleutheroembryos exposed to waterborne MeHg (0, 0.01, 0.03 and 0.1μM. Afterwards, the NLR assay was tested in 48 hpf embryos subjected to the same MeHg exposure regimes. Embryos exposed to 0.01 and 0.03μM of MeHg exhibited significant increases in locomotion in both scenarios. These findings suggest that similar locomotor phenotypes observed in free swimming fish can be detected as early as 48 hpf, when locomotion is induced with nicotine.

  16. Building neurophenomics in zebrafish: Effects of prior testing stress and test batteries.

    Science.gov (United States)

    Song, Cai; Yang, Lei; Wang, JiaJia; Chen, Peirong; Li, Shaomin; Liu, Yingcong; Nguyen, Michael; Kaluyeva, Aleksandra; Kyzar, Evan J; Gaikwad, Siddharth; Kalueff, Allan V

    2016-09-15

    The zebrafish (Danio rerio) is a promising model organism for neurophenomics - a new field of neuroscience linking neural phenotypes to various genetic and environmental factors. However, the effects of prior experimental manipulations on zebrafish performance in different behavioral paradigms remain unclear. Here, we examine the influence of selected stressful procedures and test batteries on adult zebrafish anxiety-like behaviors in two commonly used models - the novel tank (NTT) and the light-dark box (LDB) tests. While no overt behavioral differences between outbred short-fin wild-type (WT) and mutant 'pink' glowfish were seen in both tests under baseline (control) conditions, an acute severe stressor (a 30-min car transportation) detected significantly lower mutant fish anxiety-like behavior in these tests. In contrast, WT zebrafish showed no overt NTT or LDB responses following a mild stressor (5-min 40-Wt light) exposure, also showing no differences in batteries of NTT and LDB run immediately one after another, or with a 1-day interval. Collectively, these findings suggest that zebrafish may be relatively less sensitive (e.g., than other popular species, such as rodents) to the test battery effect, and show that stronger stressors may be needed (to complement low-to-moderate stress aquatic screens) to better reveal phenotypical variance in zebrafish assays. Strengthening the value of zebrafish models in neurophenotyping research, this study indicates the potential of using more test batteries and a wider spectrum of pre-test stressors in zebrafish behavioral assays.

  17. Building neurophenomics in zebrafish: Effects of prior testing stress and test batteries.

    Science.gov (United States)

    Song, Cai; Yang, Lei; Wang, JiaJia; Chen, Peirong; Li, Shaomin; Liu, Yingcong; Nguyen, Michael; Kaluyeva, Aleksandra; Kyzar, Evan J; Gaikwad, Siddharth; Kalueff, Allan V

    2016-09-15

    The zebrafish (Danio rerio) is a promising model organism for neurophenomics - a new field of neuroscience linking neural phenotypes to various genetic and environmental factors. However, the effects of prior experimental manipulations on zebrafish performance in different behavioral paradigms remain unclear. Here, we examine the influence of selected stressful procedures and test batteries on adult zebrafish anxiety-like behaviors in two commonly used models - the novel tank (NTT) and the light-dark box (LDB) tests. While no overt behavioral differences between outbred short-fin wild-type (WT) and mutant 'pink' glowfish were seen in both tests under baseline (control) conditions, an acute severe stressor (a 30-min car transportation) detected significantly lower mutant fish anxiety-like behavior in these tests. In contrast, WT zebrafish showed no overt NTT or LDB responses following a mild stressor (5-min 40-Wt light) exposure, also showing no differences in batteries of NTT and LDB run immediately one after another, or with a 1-day interval. Collectively, these findings suggest that zebrafish may be relatively less sensitive (e.g., than other popular species, such as rodents) to the test battery effect, and show that stronger stressors may be needed (to complement low-to-moderate stress aquatic screens) to better reveal phenotypical variance in zebrafish assays. Strengthening the value of zebrafish models in neurophenotyping research, this study indicates the potential of using more test batteries and a wider spectrum of pre-test stressors in zebrafish behavioral assays. PMID:27155502

  18. Characterization of Proliferating Neural Progenitors after Spinal Cord Injury in Adult Zebrafish.

    Directory of Open Access Journals (Sweden)

    Subhra Prakash Hui

    Full Text Available Zebrafish can repair their injured brain and spinal cord after injury unlike adult mammalian central nervous system. Any injury to zebrafish spinal cord would lead to increased proliferation and neurogenesis. There are presences of proliferating progenitors from which both neuronal and glial loss can be reversed by appropriately generating new neurons and glia. We have demonstrated the presence of multiple progenitors, which are different types of proliferating populations like Sox2+ neural progenitor, A2B5+ astrocyte/ glial progenitor, NG2+ oligodendrocyte progenitor, radial glia and Schwann cell like progenitor. We analyzed the expression levels of two common markers of dedifferentiation like msx-b and vimentin during regeneration along with some of the pluripotency associated factors to explore the possible role of these two processes. Among the several key factors related to pluripotency, pou5f1 and sox2 are upregulated during regeneration and associated with activation of neural progenitor cells. Uncovering the molecular mechanism for endogenous regeneration of adult zebrafish spinal cord would give us more clues on important targets for future therapeutic approach in mammalian spinal cord repair and regeneration.

  19. Anxiogenic-like effects of chronic nicotine exposure in zebrafish.

    Science.gov (United States)

    Stewart, Adam Michael; Grossman, Leah; Collier, Adam D; Echevarria, David J; Kalueff, Allan V

    2015-12-01

    Nicotine is one of the most widely used and abused legal drugs. Although its pharmacological profile has been extensively investigated in humans and rodents, nicotine CNS action remains poorly understood. The importance of finding evolutionarily conserved signaling pathways, and the need to apply high-throughput in vivo screens for CNS drug discovery, necessitate novel efficient experimental models for nicotine research. Zebrafish (Danio rerio) are rapidly emerging as an excellent organism for studying drug abuse, neuropharmacology and toxicology and have recently been applied to testing nicotine. Anxiolytic, rewarding and memory-modulating effects of acute nicotine treatment in zebrafish are consistently reported in the literature. However, while nicotine abuse is more relevant to long-term exposure models, little is known about chronic effects of nicotine on zebrafish behavior. In the present study, chronic 4-day exposure to 1-2mg/L nicotine mildly increased adult zebrafish shoaling but did not alter baseline cortisol levels. We also found that chronic exposure to nicotine evokes robust anxiogenic behavioral responses in zebrafish tested in the novel tank test paradigm. Generally paralleling clinical and rodent data on anxiogenic effects of chronic nicotine, our study supports the developing utility of zebrafish for nicotine research. PMID:25643654

  20. Mycobacterium marinum causes a latent infection that can be reactivated by gamma irradiation in adult zebrafish.

    Directory of Open Access Journals (Sweden)

    Mataleena Parikka

    2012-09-01

    Full Text Available The mechanisms leading to latency and reactivation of human tuberculosis are still unclear, mainly due to the lack of standardized animal models for latent mycobacterial infection. In this longitudinal study of the progression of a mycobacterial disease in adult zebrafish, we show that an experimental intraperitoneal infection with a low dose (≈ 35 bacteria of Mycobacterium marinum, results in the development of a latent disease in most individuals. The infection is characterized by limited mortality (25%, stable bacterial loads 4 weeks following infection and constant numbers of highly organized granulomas in few target organs. The majority of bacteria are dormant during a latent mycobacterial infection in zebrafish, and can be activated by resuscitation promoting factor ex vivo. In 5-10% of tuberculosis cases in humans, the disease is reactivated usually as a consequence of immune suppression. In our model, we are able to show that reactivation can be efficiently induced in infected zebrafish by γ-irradiation that transiently depletes granulo/monocyte and lymphocyte pools, as determined by flow cytometry. This immunosuppression causes reactivation of the dormant mycobacterial population and a rapid outgrowth of bacteria, leading to 88% mortality in four weeks. In this study, the adult zebrafish presents itself as a unique non-mammalian vertebrate model for studying the development of latency, regulation of mycobacterial dormancy, as well as reactivation of latent or subclinical tuberculosis. The possibilities for screening for host and pathogen factors affecting the disease progression, and identifying novel therapeutic agents and vaccine targets make this established model especially attractive.

  1. Cancer and inflammation studies using zebrafish cell lines

    NARCIS (Netherlands)

    He, Shuning

    2010-01-01

    As the zebrafish, Danio rerio, has been increasingly used as an animal model for biomedical research, we aimed to establish zebrafish cell line models for inflammation and cancer studies in this thesis. Several zebrafish cell lines were characterized and their genetic and physiological properties we

  2. Effect of endocrine disrupting chemicals on the transcription of genes related to the innate immune system in the early developmental stage of zebrafish (Danio rerio).

    Science.gov (United States)

    Jin, Yuanxiang; Chen, Rujia; Liu, Weiping; Fu, Zhengwei

    2010-01-01

    Health concerns regarding the potential interference of endocrine disrupting chemicals (EDCs) in the immune system of wildlife and humans have increased in recent years. However, the effects of EDCs in aquatic systems on the immune system of fish species has only received limited attention. In the present study, we found that the mRNA levels of TNFalpha, IFN, IL-1beta, IL-8, CXCL-Clc, and CC-chemokine, which are closely related to the innate immune system, were affected in newly hatched zebrafish when exposed to EDCs, such as 17beta-estradiol, 17alpha-ethynyestradiol, permethrin, atrazine and nonylphenol at various concentrations (0.1, 0.5, 2.5 and 12.5 microg/l) for three days during the embryo stage. However, the different EDCs displayed different potentials to change innate immune-related gene transcription. Among the selected chemicals, permethrin (PM) and 17beta-estradiol (E2) (12.5 microg/l) significantly increased the mRNA levels of many cytokines, exhibiting their most prominent impacts on the innate immune system of zebrafish. In addition, it was found that the mixture of the above five chemicals (2.5 microg/l each) had a greater effect on innate immune system-related gene transcription in zebrafish than equal amounts of the single compound. Moreover, the genes (such as Bcl2, Ucp2 and iNOS) relating to reactive oxygen species (ROS) and nitrogen reactive free radical production were also influenced by some EDCs and their mixture. We suggest that heavy oxidative stress and the balance of nitric oxide (NO) production lead to death of immune cells. These results may provide an explanation of the possible mode how EDCs influence the innate immune system in zebrafish. Taken together, the results obtained in the present study clearly demonstrate that EDCs and their mixtures in aquatic systems will greatly influence the immune system in fish, suggesting that the effects of EDCs on fish should be associated with immune toxicity. PMID:20153439

  3. Toxicity assessment and vitellogenin expression in zebrafish (Danio rerio) embryos and larvae acutely exposed to bisphenol A, endosulfan, heptachlor, methoxychlor and tetrabromobisphenol A.

    Science.gov (United States)

    Chow, Wing Shan; Chan, Winson Ka-Lun; Chan, King Ming

    2013-07-01

    Organochlorine pesticides and brominated flame retardants, such as tetrabromobisphenol A and polybrominated diphenyl ethers, pose an environmental hazard owing to their persistence, low solubility and estrogenic effects, and concerns have been raised regarding their effects on aquatic biota. In the present study, zebrafish embryos and larvae were used as a model to investigate the sublethal and lethal effects of three different organochlorine pesticides, namely methoxychlor, endosulfan and heptachlor, as well as the flame retardant tetrabromobisphenol A, and its precursor compound bisphenol A. Preliminary data for chemical exposure tests were obtained by determining the 96 h median effective concentration EC50 (hatching rate) and 96 h median lethal concentration LC50 . Quantitative polymerase chain reaction was used to investigate the gene expression levels of the biomarker vitellogenin (vtg1) after 96 h exposures to 10, 25, 50 and 75% of the 96 h EC50 value for embryos and 96 h LC50 value for larvae. The use of vtg1 mRNA induction in zebrafish embryos and larvae was found to be a sensitive biomarker of exposure to these organic compounds, and was helpful in elucidating their adverse effects and setting water quality guidelines.

  4. Natural mixtures of persistent organic pollutants (POPs) suppress ovarian follicle development, liver vitellogenin immunostaining and hepatocyte proliferation in female zebrafish (Danio rerio)

    Energy Technology Data Exchange (ETDEWEB)

    Kraugerud, Marianne, E-mail: Marianne.Kraugerud@nvh.no [Dept. of Basic Sciences and Aquatic Medicine, Norwegian School of Veterinary Science, POB 8146 Dep., 0033 Oslo (Norway); Doughty, Richard William, E-mail: vetrwdoughty@yahoo.co.uk [Sundveien 22, 2015 Leirsund (Norway); Lyche, Jan L., E-mail: Jan.Lyche@nvh.no [Dept. of Food Safety and Infection Biology, Norwegian School of Veterinary Science, POB 8146 Dep., 0033 Oslo (Norway); Berg, Vidar, E-mail: Vidar.Berg@nvh.no [Dept. of Food Safety and Infection Biology, Norwegian School of Veterinary Science, POB 8146 Dep., 0033 Oslo (Norway); Tremoen, Nina H., E-mail: Nina.Hardnes@nvh.no [Dept. of Production Animal Clinical Sciences, Norwegian School of Veterinary Science, POB 8146 Dep., 0033 Oslo (Norway); Alestrom, Peter, E-mail: Peter.Alestrom@nvh.no [Dept. of Basic Sciences and Aquatic Medicine, Norwegian School of Veterinary Science, POB 8146 Dep., 0033 Oslo (Norway); Aleksandersen, Mona, E-mail: Mona.Aleksandersen@nvh.no [Dept. of Basic Sciences and Aquatic Medicine, Norwegian School of Veterinary Science, POB 8146 Dep., 0033 Oslo (Norway); Ropstad, Erik, E-mail: Erik.Ropstad@nvh.no [Dept. of Production Animal Clinical Sciences, Norwegian School of Veterinary Science, POB 8146 Dep., 0033 Oslo (Norway)

    2012-07-15

    Persistent organic pollutants such as polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and dichlorodiphenyltrichloroethane (DDT) are present in high concentrations in livers of burbot (Lota lota) in Lake Mjosa, Norway. In order to assess effects of such pollutants on fish gonadal morphology, female zebrafish were exposed in two generations by food to mixtures of pollutants extracted from livers of burbot from Lake Mjosa (high and low dose) and Lake Losna, which represents background pollution, and compared to a control group. Ovarian follicle counts detected a significant decrease in late vitellogenic follicle stages in fish exposed to the Losna and the high concentrations of Mjosa mixtures in fish from the first generation. In addition, proliferation of granulosa cells, visualized by immunohistochemistry against proliferating cell nuclear antigen (PCNA), was decreased in all exposure groups in either early or late vitellogenic follicle stages compared to control. This was accompanied by increased apoptosis of granulosa cells. There was a decrease in proliferation of liver hepatocytes with exposure to both Mjosa mixtures. In addition, immunopositivity for vitellogenin in the liver was significantly lower in the Mjosa high group than in the control group. When analysing effects of parental exposure, fish with parents exposed to Mjosa high mixture had significantly higher numbers of perinucleolar follicles than fish with control parents. We conclude that long-term exposure of a real-life mixture of pollutants containing high- and background levels of chemicals supress ovarian follicle development, liver vitellogenin immunostaining intensity and hepatocyte proliferation in the zebrafish model.

  5. Neuroendocrine control of ionic balance in zebrafish.

    Science.gov (United States)

    Kwong, Raymond W M; Kumai, Yusuke; Perry, Steve F

    2016-08-01

    Zebrafish (Danio rerio) is an emerging model for integrative physiological research. In this mini-review, we discuss recent advances in the neuroendocrine control of ionic balance in this species, and identify current knowledge gaps and issues that would benefit from further investigation. Zebrafish inhabit a hypo-ionic environment and therefore are challenged by a continual loss of ions to the water. To maintain ionic homeostasis, they must actively take up ions from the water and reduce passive ion loss. The adult gill or the skin of larvae are the primary sites of ionic regulation. Current models for the uptake of major ions in zebrafish incorporate at least three types of ion transporting cells (also called ionocytes); H(+)-ATPase-rich cells for Na(+) uptake, Na(+)/K(+)-ATPase-rich cells for Ca(2+) uptake, and Na(+)/Cl(-)-cotransporter expressing cells for both Na(+) and Cl(-) uptake. The precise molecular mechanisms regulating the paracellular loss of ions remain largely unknown. However, epithelial tight junction proteins, including claudins, are thought to play a critical role in reducing ion losses to the surrounding water. Using the zebrafish model, several key neuroendocrine factors were identified as regulators of epithelial ion movement, including the catecholamines (adrenaline and noradrenaline), cortisol, the renin-angiotensin system, parathyroid hormone and prolactin. Increasing evidence also suggests that gasotransmitters, such as H2S, are involved in regulating ion uptake. PMID:27179885

  6. Natural mixtures of persistent organic pollutants (POPs) suppress ovarian follicle development, liver vitellogenin immunostaining and hepatocyte proliferation in female zebrafish (Danio rerio)

    International Nuclear Information System (INIS)

    Persistent organic pollutants such as polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and dichlorodiphenyltrichloroethane (DDT) are present in high concentrations in livers of burbot (Lota lota) in Lake Mjøsa, Norway. In order to assess effects of such pollutants on fish gonadal morphology, female zebrafish were exposed in two generations by food to mixtures of pollutants extracted from livers of burbot from Lake Mjøsa (high and low dose) and Lake Losna, which represents background pollution, and compared to a control group. Ovarian follicle counts detected a significant decrease in late vitellogenic follicle stages in fish exposed to the Losna and the high concentrations of Mjøsa mixtures in fish from the first generation. In addition, proliferation of granulosa cells, visualized by immunohistochemistry against proliferating cell nuclear antigen (PCNA), was decreased in all exposure groups in either early or late vitellogenic follicle stages compared to control. This was accompanied by increased apoptosis of granulosa cells. There was a decrease in proliferation of liver hepatocytes with exposure to both Mjøsa mixtures. In addition, immunopositivity for vitellogenin in the liver was significantly lower in the Mjøsa high group than in the control group. When analysing effects of parental exposure, fish with parents exposed to Mjøsa high mixture had significantly higher numbers of perinucleolar follicles than fish with control parents. We conclude that long-term exposure of a real-life mixture of pollutants containing high- and background levels of chemicals supress ovarian follicle development, liver vitellogenin immunostaining intensity and hepatocyte proliferation in the zebrafish model.

  7. Contrast-Enhanced X-Ray Micro-Computed Tomography as a Versatile Method for Anatomical Studies of Adult Zebrafish.

    Science.gov (United States)

    Babaei, Fatemeh; Hong, Tony Liu Chi; Yeung, Kelvin; Cheng, Shuk Han; Lam, Yun Wah

    2016-08-01

    One attractive quality of zebrafish as a model organism for biological research is that transparency at early developmental stages allows the optical imaging of cellular and molecular events. However, this advantage cannot be applied to adult zebrafish. In this study, we explored the use of contrast-enhanced X-ray micro-computed tomography (microCT) on adult zebrafish in which the organism was stained with iodine, a simple and economical contrasting agent, after fixation. Tomographic reconstruction of the microCT data allowed the three-dimensional (3D) volumetric analyses of individual organs in adult zebrafish. Adipose tissues showed a higher affinity to iodine and were more strongly contrasted in microCT. As traditional histological techniques often involve dehydration steps that remove tissue lipids, iodine-contrasted microCT offers a convenient method for visualizing fat deposition in fish. Utilizing this advantage, we discovered a transient accumulation of lipids around the heart after ventricular amputation, suggesting a correlation between lipid distribution and heart regeneration. Taken together, microCT is a versatile technique that enables the 3D visualization of zebrafish organs, as well as other fish models, in their anatomical context. This simple method is a valuable new addition to the arsenal of techniques available to this model organism. PMID:27058023

  8. TBBPA chronic exposure produces sex-specific neurobehavioral and social interaction changes in adult zebrafish.

    Science.gov (United States)

    Chen, Jiangfei; Tanguay, Robert L; Simonich, Michael; Nie, Shangfei; Zhao, Yuxin; Li, Lelin; Bai, Chenglian; Dong, Qiaoxiang; Huang, Changjiang; Lin, Kuangfei

    2016-01-01

    The toxicity of tetrabromobisphenol A (TBBPA) has been extensively studied because of its high production volume. TBBPA is toxic to aquatic fish based on acute high concentration exposure tests, and few studies have assessed the behavioral effects of low concentration chronic TBBPA exposures in aquatic organisms. The present study defined the developmental and neurobehavioral effects associated with exposure of zebrafish to 0, 5 and 50nM TBBPA during 1-120days post-fertilization (dpf) following by detoxification for four months before the behaviors assessment. These low concentration TBBPA exposures were not associated with malformations and did not alter sex ratio, but resulted in reduced zebrafish body weight and length. Adult behavioral assays indicated that TBBPA exposed males had significantly higher average swim speeds and spent significantly more time in high speed darting mode and less time in medium cruising mode compared to control males. In an adult photomotor response assay, TBBPA exposure was associated with hyperactivity in male fish. Female zebrafish responses in these assays followed a similar trend, but the magnitude of TBBPA effects was generally smaller than in males. Social interaction evaluated using a mirror attack test showed that 50nM TBBPA exposed males had heightened aggression. Females exposed to 50nM TBBPA spent more time in the vicinity of the mirror, but did not show increased aggression toward the mirror compared to unexposed control fish. Overall, the hyperactivity and social behavior deficits ascribed here to chronic TBBPA exposure was most profound in males. Our findings indicate that TBBPA can cause developmental and neurobehavioral deficits, and may pose significant health risk to humans. PMID:27221227

  9. (Danio rerio

    Directory of Open Access Journals (Sweden)

    F Prieto García

    2007-01-01

    Full Text Available El objetivo del trabajo fue estudiar los daños teratogénicos y la inducción de micronúcleos en células branquiales de peces cebra (Danio rerio por presencia de arsénico en las aguas. Fueron mantenidos en aguas bicarbonatadas cálcicas magnésicas de un pozo de referencia y del pozo “Zimapán 5”, del Municipio Zimapán, Estado de Hidalgo, México. Este último, con un contenido de arsénico que varía de 0,395-0,630 mg/L. Para el estudio de genotoxicidad se evaluaron durante 180 días en 3 tratamientos: agua del pozo de referencia (control negativo, sin As, agua del pozo de referencia adicionada con 5,0 mg As (V/L (control positivo, y en agua del pozo “Zimapán 5”, colocándose 65 especimenes por tratamiento. Después de 30 días hubo una disminución de As en el agua del control positivo de 1092,65 ppb (36,42 ppb/día mientras en pescados hubo un incremento de 523,81 ppb (17,46 ppb/día. Para el agua del pozo “Zimapán 5” hubo una disminución de 211,40 ppb (7,04 ppb/día, y en pescados hubo un incremento de 74,73 ppb (2,49 ppb/día. Este resultado pone de manifiesto el alto grado de bioacumulación de As en el pez, que en relación al control negativo muestra que es 2,54 veces mayor. En relación a la frecuencia de inducción de micronúcleos en células branquiales, al final de los 180 días en el control negativo hubo una generación espontánea de 0,8 micronúcleos/1000 células, en el control positivo hubo una frecuencia de inducción de micronúcleos 163,5 veces mayor que en el control negativo, mientras que en los peces expuestos al agua del pozo “Zimapán 5” fue 56,25 veces mayor con respecto al mismo. Estos resultados demuestran la genotoxicidad del As en Danio rerio. Para el estudio de teratogénesis, se colocó una hembra y un macho en apareamiento en las mismas condiciones de los tratamientos, obteniendo que a mayor concentración de As en el agua mayor porcentaje de huevos no viables, menor porcentaje de huevos viables

  10. Notch receptor expression in neurogenic regions of the adult zebrafish brain.

    Directory of Open Access Journals (Sweden)

    Vanessa de Oliveira-Carlos

    Full Text Available The adult zebrash brain has a remarkable constitutive neurogenic capacity. The regulation and maintenance of its adult neurogenic niches are poorly understood. In mammals, Notch signaling is involved in stem cell maintenance both in embryonic and adult CNS. To better understand how Notch signaling is involved in stem cell maintenance during adult neurogenesis in zebrafish we analysed Notch receptor expression in five neurogenic zones of the adult zebrafish brain. Combining proliferation and glial markers we identified several subsets of Notch receptor expressing cells. We found that 90 [Formula: see text] of proliferating radial glia express notch1a, notch1b and notch3. In contrast, the proliferating non-glial populations of the dorsal telencephalon and hypothalamus rarely express notch3 and about half express notch1a/1b. In the non-proliferating radial glia notch3 is the predominant receptor throughout the brain. In the ventral telencephalon and in the mitotic area of the optic tectum, where cells have neuroepithelial properties, notch1a/1b/3 are expressed in most proliferating cells. However, in the cerebellar niche, although progenitors also have neuroepithelial properties, only notch1a/1b are expressed in a high number of PCNA [Formula: see text] cells. In this region notch3 expression is mostly in Bergmann glia and at low levels in few PCNA [Formula: see text] cells. Additionally, we found that in the proliferation zone of the ventral telencephalon, Notch receptors display an apical high to basal low gradient of expression. Notch receptors are also expressed in subpopulations of oligodendrocytes, neurons and endothelial cells. We suggest that the partial regional heterogeneity observed for Notch expression in progenitor cells might be related to the cellular diversity present in each of these neurogenic niches.

  11. Toxic effects of aflatoxin B1 on embryonic development of zebrafish (Danio rerio): potential activity of piceatannol encapsulated chitosan/poly (lactic acid) nanoparticles.

    Science.gov (United States)

    Dhanapal, Jeevitha; Ravindrran, Malathy Balaraman; Baskar, Santhosh K

    2015-01-01

    The aim was to analyse the efficacy of piceatannol (PIC) loaded chitosan (CS)/poly(lactic acid)(PLA) nanoparticles (CS/PLA-PIC NPs) in zebra fish embryos exposed to aflatoxin B1 (AFB1). FTIR confirmed the chemical interaction between the polymers and drug. SEM showed the size of CS/PLA-PIC NPs approximately 87 to 200nm, compared to CS-PLA NPs of 150nm size. The size was further affirmed as 127nm (CS-PLA NPs) and 147nm (CS/PLA-PIC NPs) by zetasizer depiction. CS/PLA-PIC NPs have not illustrated toxicity at high concentrations when tested in zebrafish embryos. AFB1 wielded their toxic effects on the survival, spontaneous movement, hatching and heart rate and development of embryos were observed in both time and dose-dependent manner at 4μM. Our results suggested that the addition of CS/PLA-PIC NPs increases the survival, heart rate and hatching in time dependent manner at the dosage of 20μg/ml. These hopeful results may prompt the advancement of drug encapsulated polymeric nanoparticles which may have the potential role in improving the AFB1 induced toxicity in humans as well. PMID:25322988

  12. Effects of Nanosilver Exposure on Cholinesterase Activities, CD41, and CDF/LIF-Like Expression in ZebraFish (Danio rerio Larvae

    Directory of Open Access Journals (Sweden)

    Marzhan Myrzakhanova

    2013-01-01

    Full Text Available Metal nanosolicoparticles are suspected to cause diseases in a number of organisms, including man. In this paper, we report the effects of nanosilver (Ag, 1–20 nm particles on the early development of the zebrafish, a well-established vertebrate model. Embryos at the midgastrula stage were exposed to concentrations ranging from 100 to 0.001 mg/L to verify the effects on different endpoints: lethality, morphology, expression of cholinergic molecules, and development of the immune system. (1 Relative risk of mortality was exponential in the range between 0.001 and 10 mg/L. Exposure to 100 mg/L caused 100% death of embryos before reaching the tail-bud stage. (2 Developmental anomalies were present in the 72 h larvae obtained from embryos exposed to nanosilver: whole body length, decreased eye dimension, and slow response to solicitation by gentle touch with a needle tip, with a significant threshold at 0.1 mg/L. (3 Dose-dependent inhibition of acetylcholinesterase activity was significant among the exposures, except between 1 mg/L and 10 mg/L. (4 The distribution of CD41+ cells and of CDF/LIF-like immunoreactivity was altered according to the Ag concentration. The possible effect of nanosilver in impairing immune system differentiation through the inhibition of molecules related to the cholinergic system is discussed.

  13. Adult neural stem cell behavior underlying constitutive and restorative neurogenesis in zebrafish.

    Science.gov (United States)

    Barbosa, Joana S; Ninkovic, Jovica

    2016-01-01

    Adult Neural Stem Cells (aNSCs) generate new neurons that integrate into the pre-existing networks in specific locations of the Vertebrate brain. Moreover, aNSCs contribute with new neurons to brain regeneration in some non-mammalian Vertebrates. The similarities and the differences in the cellular and molecular processes governing neurogenesis in the intact and regenerating brain are still to be assessed. Toward this end, we recently established a protocol for non-invasive imaging of aNSC behavior in their niche in vivo in the adult intact and regenerating zebrafish telencephalon. We observed different modes of aNSC division in the intact brain and a novel mode of neurogenesis by direct conversion, which contributes to stem cell depletion with age. After injury, the generation of neurons is increased both by the activation of additional aNSCs and a shift in the division mode of aNSCs, thereby contributing to the successful neuronal regeneration. The cellular behavior we observed opens new questions regarding long-term aNSC maintenance in homeostasis and in regeneration. In this commentary we discuss our data and new questions arising in the context of aNSC behavior, not only in zebrafish but also in other species, including mammals. PMID:27606336

  14. Zebrafish Craniofacial Development: A Window into Early Patterning.

    Science.gov (United States)

    Mork, Lindsey; Crump, Gage

    2015-01-01

    The formation of the face and skull involves a complex series of developmental events mediated by cells derived from the neural crest, endoderm, mesoderm, and ectoderm. Although vertebrates boast an enormous diversity of adult facial morphologies, the fundamental signaling pathways and cellular events that sculpt the nascent craniofacial skeleton in the embryo have proven to be highly conserved from fish to man. The zebrafish Danio rerio, a small freshwater cyprinid fish from eastern India, has served as a popular model of craniofacial development since the 1990s. Unique strengths of the zebrafish model include a simplified skeleton during larval stages, access to rapidly developing embryos for live imaging, and amenability to transgenesis and complex genetics. In this chapter, we describe the anatomy of the zebrafish craniofacial skeleton; its applications as models for the mammalian jaw, middle ear, palate, and cranial sutures; the superior imaging technology available in fish that has provided unprecedented insights into the dynamics of facial morphogenesis; the use of the zebrafish to decipher the genetic underpinnings of craniofacial biology; and finally a glimpse into the most promising future applications of zebrafish craniofacial research.

  15. LIGHT / DARK PREFERENCE IN Danio rerio: EFFECTS OF LIGHT EXPOSURE DURATION AND DAY PERIOD

    Directory of Open Access Journals (Sweden)

    Claudio Alberto Gellis de Mattos Dias

    2014-10-01

    Full Text Available The animals have anatomical and physiological structures influenced by luminosity. In fish, the pineal gland cells contain photoreceptors and the suprachiasmatic nucleus seems to be involved in biological rhythm just like in other vertebrates. This work aims to describe the role of luminosity and day periods in Danio rerio's Light/Dark preference. For this purpose 160 naive adult undetermined sex Zebrafish were divided into 5 groups of 32 subjects and kept in isolated aquaria with light control. Afterwards, each fish was tested in the Light/Dark aquaria, with water column of 5 centimeters. There was an habituation period of 5 minutes (300 seconds followed by removal of the sliding doors, allowing the subjects to explore the apparatus for 15 minutes (900 seconds. Tests were performed in different day periods, as follows: Morning (06:00 – 12:00 h; Afternoon (12:00 – 18:00 h; Night (18:00 – 24:00 h; Late Night (24:00 – 06:00 h. Our results show that the time of permanence is sensitive to day period. The number of crossings and latency were not influenced by the period of the day. Further studies regarding biological basis of Light/Dark Preference should be carried out in order to understand the role of circadian function in Danio rerio's behavior. Keywords: Danio rerio, zebrafish, behavior, light-dark preference, anxiety. DOI: http://dx.doi.org/10.18561/2179-5746/biotaamazonia.v4n3p106-111

  16. Impact of antibiotic treatments on the expression of the R plasmid tra genes and on the host innate immune activity during pRAS1 bearing Aeromonas hydrophila infection in zebrafish (Danio rerio

    Directory of Open Access Journals (Sweden)

    Cantas Leon

    2012-03-01

    Full Text Available Abstract Background The transfer of R plasmids between bacteria has been well studied under laboratory conditions and the transfer frequency has been found to vary between plasmids and under various physical conditions. For the first time, we here study the expression of the selected plasmid mobility genes traD, virB11 and virD4 in the 45 kb IncU plasmid, pRAS1, conferring resistance to tetracycline, trimethoprim and sulphonamide, using an in vivo zebrafish infection- treatment model. Results Three days after oral infection of adult zebrafish with Aeromonas hydrophila harboring pRAS1, elevated expression of pro-inflammatory cytokine (TNF α, IL-1β and IL-8 and complement C3 genes in the intestine coincided with disease symptoms. Tetracycline, trimethoprim and an ineffective concentration of flumequine given 48 h prior to sampling, strongly increased expression of plasmid mobility genes, whereas an effective dosage of flumequine resulted in lower levels of mRNA copies of these genes relative to placebo treatment. Following effective treatment with flumequine, and ineffective treatments with a low concentration of flumequine, with trimethoprim or with sulphonamide, the intestinal expression of immune genes was strongly induced compared to placebo treated control fish. Conclusions Treatment of zebrafish infected with an antibiotic resistant (TcR, TmR, SuR A. hydrophila with ineffective concentrations of flumequine or the ineffective antimicrobials tetracycline and trimethoprim strongly induced expression of genes mediating conjugative transfer of the R-plasmid pRAS1. Simultaneously, there was a strong induction of selected inflammatory and immune response genes, which was again evident in fish subjected to ineffective treatment protocols. Our findings point to the essential role of therapeutic practices in escalation or control of antibiotic resistance transfer, and suggest that antibiotic substances, even in sub-inhibitory concentrations, may

  17. Gaining translational momentum: more zebrafish models for neuroscience research.

    Science.gov (United States)

    Kalueff, Allan V; Echevarria, David J; Stewart, Adam Michael

    2014-12-01

    Zebrafish (Danio rerio) are rapidly becoming a popular model organism in translational neuroscience and biological psychiatry research. Here we discuss conceptual, practical and other related aspects of using zebrafish in this field ("from tank to bedside"), and critically evaluate both advantages and limitations of zebrafish models of human brain disorders. We emphasize the need to more actively develop zebrafish models for neuroscience research focusing on complex traits. PMID:24593944

  18. Alternate Immersion in an External Glucose Solution Differentially Affects Blood Sugar Values in Older Versus Younger Zebrafish Adults.

    Science.gov (United States)

    Connaughton, Victoria P; Baker, Cassandra; Fonde, Lauren; Gerardi, Emily; Slack, Carly

    2016-04-01

    Recently, zebrafish have been used to examine hyperglycemia-induced complications (retinopathy and neuropathy), as would occur in individuals with diabetes. Current models to induce hyperglycemia in zebrafish include glucose immersion and streptozotocin injections. Both are effective, although neither is reported to elevate blood sugar values for more than 1 month. In this article, we report differences in hyperglycemia induction and maintenance in young (4-11 months) versus old (1-3 years) zebrafish adults. In particular, older fish immersed in an alternating constant external glucose solution (2%) for 2 months displayed elevated blood glucose levels for the entire experimental duration. In contrast, younger adults displayed only transient hyperglycemia, suggesting the fish were acclimating to the glucose exposure protocol. However, modifying the immersion protocol to include a stepwise increasing glucose concentration (from 1% → 2%→3%) resulted in maintained hyperglycemia in younger zebrafish adults for up to 2 months. Glucose-exposed younger fish collected after 8 weeks of exposure also displayed a significant decrease in wet weight. Taken together, these data suggest different susceptibilities to hyperglycemia in older and younger fish and that stepwise increasing glucose concentrations of 1% are required for maintenance of hyperglycemia in younger adults, with higher concentrations of glucose resulting in greater increases in blood sugar values. PMID:26771444

  19. Expression of CYP11 a1 in different developmental phases of gonad in zebrafish Danio rerio%斑马鱼CYP11 a1基因在不同性腺发育时期的表达

    Institute of Scientific and Technical Information of China (English)

    陈孝红; 仇雪梅; 郝薇薇; 王秀利

    2015-01-01

    The expression of CYP11 a1 gene was studied and analyzed in four tissues and three development phases in gonad of zebrafish Danio rerio by quantitative Real-time PCR (qRT-PCR). It was found that the CYP11a1 gene was expressed in ovary, testis, muscle and brain, the minimum in brain(P0. 05), 1. 7 times higher be-fore sexual maturity and 1. 5 times higher after sexual maturity compared with that at maturity phase. In the testis, however, the expression of CYP11a1 gene was found to be enhanced first in the early development phases of testis and then decreased in the later development phases of testis, the maximum at the sexual maturity(P0.05),在卵巢成熟前期、卵巢成熟后期的表达量分别为卵巢成熟期表达量的1.7倍、1.5倍;CYP11a1基因在3个精巢发育时期的表达量表现为先升高后降低的趋势,在精巢成熟期表达量最高( P<0.05),分别为精巢成熟前期、精巢成熟后期表达量的6.5倍、13.4倍。研究表明,尽管CYP11a1基因在卵巢和精巢发育过程中的表达规律不同,但CYP11a1基因在一定程度上与斑马鱼的性腺发育相关,其可能在促进斑马鱼精子成熟中发挥一定作用。

  20. Using the Larval Zebrafish Locomotor Asssay in Functional Neurotoxicity Screening: Light Brightness and the Order of Stimulus Presentation Affect the Outcome

    Science.gov (United States)

    We are evaluating methods to screen/prioritize large numbers of chemicals using 6 day old zebrafish (Danio rerio) as an alternative model for detecting neurotoxic effects. Our behavioral testing paradigm simultaneously tests individual larval zebrafish under sequential light and...

  1. Triclosan Exposure Is Associated with Rapid Restructuring of the Microbiome in Adult Zebrafish.

    Directory of Open Access Journals (Sweden)

    Christopher A Gaulke

    Full Text Available Growing evidence indicates that disrupting the microbial community that comprises the intestinal tract, known as the gut microbiome, can contribute to the development or severity of disease. As a result, it is important to discern the agents responsible for microbiome disruption. While animals are frequently exposed to a diverse array of environmental chemicals, little is known about their effects on gut microbiome stability and structure. Here, we demonstrate how zebrafish can be used to glean insight into the effects of environmental chemical exposure on the structure and ecological dynamics of the gut microbiome. Specifically, we exposed forty-five adult zebrafish to triclosan-laden food for four or seven days or a control diet, and analyzed their microbial communities using 16S rRNA amplicon sequencing. Triclosan exposure was associated with rapid shifts in microbiome structure and diversity. We find evidence that several operational taxonomic units (OTUs associated with the family Enterobacteriaceae appear to be susceptible to triclosan exposure, while OTUs associated with the genus Pseudomonas appeared to be more resilient and resistant to exposure. We also found that triclosan exposure is associated with topological alterations to microbial interaction networks and results in an overall increase in the number of negative interactions per microbe in these networks. Together these data indicate that triclosan exposure results in altered composition and ecological dynamics of microbial communities in the gut. Our work demonstrates that because zebrafish afford rapid and inexpensive interrogation of a large number of individuals, it is a useful experimental system for the discovery of the gut microbiome's interaction with environmental chemicals.

  2. Triclosan Exposure Is Associated with Rapid Restructuring of the Microbiome in Adult Zebrafish.

    Science.gov (United States)

    Gaulke, Christopher A; Barton, Carrie L; Proffitt, Sarah; Tanguay, Robert L; Sharpton, Thomas J

    2016-01-01

    Growing evidence indicates that disrupting the microbial community that comprises the intestinal tract, known as the gut microbiome, can contribute to the development or severity of disease. As a result, it is important to discern the agents responsible for microbiome disruption. While animals are frequently exposed to a diverse array of environmental chemicals, little is known about their effects on gut microbiome stability and structure. Here, we demonstrate how zebrafish can be used to glean insight into the effects of environmental chemical exposure on the structure and ecological dynamics of the gut microbiome. Specifically, we exposed forty-five adult zebrafish to triclosan-laden food for four or seven days or a control diet, and analyzed their microbial communities using 16S rRNA amplicon sequencing. Triclosan exposure was associated with rapid shifts in microbiome structure and diversity. We find evidence that several operational taxonomic units (OTUs) associated with the family Enterobacteriaceae appear to be susceptible to triclosan exposure, while OTUs associated with the genus Pseudomonas appeared to be more resilient and resistant to exposure. We also found that triclosan exposure is associated with topological alterations to microbial interaction networks and results in an overall increase in the number of negative interactions per microbe in these networks. Together these data indicate that triclosan exposure results in altered composition and ecological dynamics of microbial communities in the gut. Our work demonstrates that because zebrafish afford rapid and inexpensive interrogation of a large number of individuals, it is a useful experimental system for the discovery of the gut microbiome's interaction with environmental chemicals. PMID:27191725

  3. Somatic mutagenesis with a Sleeping Beauty transposon system leads to solid tumor formation in zebrafish.

    Directory of Open Access Journals (Sweden)

    Maura McGrail

    Full Text Available Large-scale sequencing of human cancer genomes and mouse transposon-induced tumors has identified a vast number of genes mutated in different cancers. One of the outstanding challenges in this field is to determine which genes, when mutated, contribute to cellular transformation and tumor progression. To identify new and conserved genes that drive tumorigenesis we have developed a novel cancer model in a distantly related vertebrate species, the zebrafish, Danio rerio. The Sleeping Beauty (SB T2/Onc transposon system was adapted for somatic mutagenesis in zebrafish. The carp ß-actin promoter was cloned into T2/Onc to create T2/OncZ. Two transgenic zebrafish lines that contain large concatemers of T2/OncZ were isolated by injection of linear DNA into the zebrafish embryo. The T2/OncZ transposons were mobilized throughout the zebrafish genome from the transgene array by injecting SB11 transposase RNA at the 1-cell stage. Alternatively, the T2/OncZ zebrafish were crossed to a transgenic line that constitutively expresses SB11 transposase. T2/OncZ transposon integration sites were cloned by ligation-mediated PCR and sequenced on a Genome Analyzer II. Between 700-6800 unique integration events in individual fish were mapped to the zebrafish genome. The data show that introduction of transposase by transgene expression or RNA injection results in an even distribution of transposon re-integration events across the zebrafish genome. SB11 mRNA injection resulted in neoplasms in 10% of adult fish at ∼10 months of age. T2/OncZ-induced zebrafish tumors contain many mutated genes in common with human and mouse cancer genes. These analyses validate our mutagenesis approach and provide additional support for the involvement of these genes in human cancers. The zebrafish T2/OncZ cancer model will be useful for identifying novel and conserved genetic drivers of human cancers.

  4. Characterization of DNA polymerase β from Danio rerio by overexpression in E. coli using the in vivo/in vitro compatible pIVEX plasmid

    OpenAIRE

    Ishikawa Mitsuru; Yamazaki Naoshi; Ishido Tomomi; Hirano Ken

    2011-01-01

    Abstract Background Eukaryotic DNA polymerase β (pol β), the polymerase thought to be responsible for DNA repair synthesis, has been extensively characterized in rats and humans. However, pol β has not been purified or enzymatically characterized from the model fish species Danio rerio (zebrafish). We used the in vitro/in vivo dual expression system plasmid, pIVEX, to express Danio rerio pol β (Danio pol β) for biochemical characterization. Results Danio pol β encoded by the in vitro/in vivo-...

  5. WNK1/HSN2 mutation in human peripheral neuropathy deregulates KCC2 expression and posterior lateral line development in zebrafish (Danio rerio.

    Directory of Open Access Journals (Sweden)

    Valérie Bercier

    Full Text Available Hereditary sensory and autonomic neuropathy type 2 (HSNAII is a rare pathology characterized by an early onset of severe sensory loss (all modalities in the distal limbs. It is due to autosomal recessive mutations confined to exon "HSN2" of the WNK1 (with-no-lysine protein kinase 1 serine-threonine kinase. While this kinase is well studied in the kidneys, little is known about its role in the nervous system. We hypothesized that the truncating mutations present in the neural-specific HSN2 exon lead to a loss-of-function of the WNK1 kinase, impairing development of the peripheral sensory system. To investigate the mechanisms by which the loss of WNK1/HSN2 isoform function causes HSANII, we used the embryonic zebrafish model and observed strong expression of WNK1/HSN2 in neuromasts of the peripheral lateral line (PLL system by immunohistochemistry. Knocking down wnk1/hsn2 in embryos using antisense morpholino oligonucleotides led to improper PLL development. We then investigated the reported interaction between the WNK1 kinase and neuronal potassium chloride cotransporter KCC2, as this transporter is a target of WNK1 phosphorylation. In situ hybridization revealed kcc2 expression in mature neuromasts of the PLL and semi-quantitative RT-PCR of wnk1/hsn2 knockdown embryos showed an increased expression of kcc2 mRNA. Furthermore, overexpression of human KCC2 mRNA in embryos replicated the wnk1/hsn2 knockdown phenotype. We validated these results by obtaining double knockdown embryos, both for wnk1/hsn2 and kcc2, which alleviated the PLL defects. Interestingly, overexpression of inactive mutant KCC2-C568A, which does not extrude ions, allowed a phenocopy of the PLL defects. These results suggest a pathway in which WNK1/HSN2 interacts with KCC2, producing a novel regulation of its transcription independent of KCC2's activation, where a loss-of-function mutation in WNK1 induces an overexpression of KCC2 and hinders proper peripheral sensory nerve

  6. COMPARATIVE EXPRESSION ANALYSIS OF GHR SIGNALING RELATED FACTORS IN ZEBRAFISH (DANIO RERIO) AND AN IN VIVO MODEL TO STUDY GHR SIGNALING%生长激素受体信号相关因子在斑马鱼中的比较表达分析及GHR信号通路体内研究模型的建立

    Institute of Scientific and Technical Information of China (English)

    Abu Shufian Ishtiaq Ahmed; 于力群; 朱作言; 孙永华

    2011-01-01

    GHR信号通路在动物出生后的生长中扮演着重要角色.实验利用斑马鱼模型研究了GHR信号相关基因在成体组织、胚胎发育以及幼体期的表达情况,这些基因包括gh、ghra、ghrb、jak2a、jak2b、statS.1、stat5.2、igf1、c-fos、socsl和socs2.值得关注的是,上述的大部分基因都存在母源性表达,且它们的合子表达均起始在体节早期之前.这说明在有功能性的脑垂体形成之前和完善的循环系统建立之前,GH及GH信号相关因子就已经存在于早期胚胎中,因此GH很可能是控制胚胎发育的一系列自分泌/旁分泌生长因子中的一员.同时,我们发现成体组织的SocS表达水平与GH信号靶基因igf1和c-fos的表达呈某种程度的负相关.我们利用实时定量PCR技术和荧光素酶分析技术,通过注射GH和GHR表达载体,在斑马鱼胚胎中分析了它们促进GH信号靶基因c-fos和igfl转录活性以及GH应激启动子spi12.1活性的能力.由此,研究利用斑马鱼胚胎建立一个体内研究模型来评估发育过程中的GH信号激活(GHSA).在受精后1天(dpf)和3dpf斑马鱼胚胎中,单独过表达gh或ghr均可以显著刺激GHSA,这表明在ldpf的斑马鱼胚胎中即存在功能性的GH和GHR蛋白表达,而这一时期是在功能性垂体的形成之前的.gh以及ghr的协同过表达则可以显著放大gh或ghr单独过表达的GHSA效果.%Growth hormone receptor (GHR) signaling pathway plays an important role in postnatal growth of animals.Although significant progress has been made in elucidating the signaling pathways activated by GHR in recent years,a comparative expression analysis of all the GHR signaling related genes and evaluation of GH-signal activation (GHSA)in an in vivo model still remain elusive.The zebrafish (Danio rerio) is an excellent model organism to study both developmental and physiological processes.In the present study,we comparatively analyzed the expression of GHR signal related

  7. Identification of estrogen target genes during zebrafish embryonic development through transcriptomic analysis.

    Directory of Open Access Journals (Sweden)

    Ruixin Hao

    Full Text Available Estrogen signaling is important for vertebrate embryonic development. Here we have used zebrafish (Danio rerio as a vertebrate model to analyze estrogen signaling during development. Zebrafish embryos were exposed to 1 µM 17β-estradiol (E2 or vehicle from 3 hours to 4 days post fertilization (dpf, harvested at 1, 2, 3 and 4 dpf, and subjected to RNA extraction for transcriptome analysis using microarrays. Differentially expressed genes by E2-treatment were analyzed with hierarchical clustering followed by biological process and tissue enrichment analysis. Markedly distinct sets of genes were up and down-regulated by E2 at the four different time points. Among these genes, only the well-known estrogenic marker vtg1 was co-regulated at all time points. Despite this, the biological functional categories targeted by E2 were relatively similar throughout zebrafish development. According to knowledge-based tissue enrichment, estrogen responsive genes were clustered mainly in the liver, pancreas and brain. This was in line with the developmental dynamics of estrogen-target tissues that were visualized using transgenic zebrafish containing estrogen responsive elements driving the expression of GFP (Tg(5xERE:GFP. Finally, the identified embryonic estrogen-responsive genes were compared to already published estrogen-responsive genes identified in male adult zebrafish (Gene Expression Omnibus database. The expressions of a few genes were co-regulated by E2 in both embryonic and adult zebrafish. These could potentially be used as estrogenic biomarkers for exposure to estrogens or estrogenic endocrine disruptors in zebrafish. In conclusion, our data suggests that estrogen effects on early embryonic zebrafish development are stage- and tissue- specific.

  8. Genes of the adaptive immune system are expressed early in zebrafish larval development following lipopolysaccharide stimulation

    Institute of Scientific and Technical Information of China (English)

    LI Fengling; ZHANG Shicui; WANG Zhiping; LI Hongyan

    2011-01-01

    Information regarding immunocompetence of the adaptive immune system (AIS) in zebrafish Danio rerio remains limited. Here, we stimulated an immune response in fish embryos,larvae and adults using lipopolysaccharide (LPS) and measured the upregulation of a number of AIS-related genes (Rag2, AID, TCRAC, IgLC-1, mIg, sIg, IgZ and DAB) 3 and 18 h later. We found that all of the genes evaluated were strongly induced following LPS stimulation, with most of them responding at 8 d post fertilization. This confirms that a functional adaptive immune response is present in D. rerio larvae, and provides a window for further functional analyses.

  9. Single-cell in vivo imaging of adult neural stem cells in the zebrafish telencephalon.

    Science.gov (United States)

    Barbosa, Joana S; Di Giaimo, Rossella; Götz, Magdalena; Ninkovic, Jovica

    2016-08-01

    Adult neural stem cells (aNSCs) in zebrafish produce mature neurons throughout their entire life span in both the intact and regenerating brain. An understanding of the behavior of aNSCs in their intact niche and during regeneration in vivo should facilitate the identification of the molecular mechanisms controlling regeneration-specific cellular events. A greater understanding of the process in regeneration-competent species may enable regeneration to be achieved in regeneration-incompetent species, including humans. Here we describe a protocol for labeling and repetitive imaging of aNSCs in vivo. We label single aNSCs, allowing nonambiguous re-identification of single cells in repetitive imaging sessions using electroporation of a red-reporter plasmid in Tg(gfap:GFP)mi2001 transgenic fish expressing GFP in aNSCs. We image using two-photon microscopy through the thinned skull of anesthetized and immobilized fish. Our protocol allows imaging every 2 d for a period of up to 1 month. This methodology allowed the visualization of aNSC behavior in vivo in their natural niche, in contrast to previously available technologies, which rely on the imaging of either dissociated cells or tissue slices. We used this protocol to follow the mode of aNSC division, fate changes and cell death in both the intact and injured zebrafish telencephalon. This experimental setup can be widely used, with minimal prior experience, to assess key factors for processes that modulate aNSC behavior. A typical experiment with data analysis takes up to 1.5 months. PMID:27362338

  10. Mapping of zebrafish research: a global outlook.

    Science.gov (United States)

    Kinth, Priyamvadah; Mahesh, Gopalakrishnan; Panwar, Yatish

    2013-12-01

    On the basis of analysis of 17,151 records on zebrafish identified from Zebrafish Information Network: the zebrafish model organism database and Web of Science, the research performance on this model organism has been evaluated. The earliest research work on zebrafish as reflected in the databases goes back to 1951. After a rather slow growth till the 1980s, research on zebrafish gained momentum in the 1990s. Analysis shows a rapid and consistent increase in the publication output with 226 publications in the year 1996, to 1929 publications in the year 2012. The prominent areas of zebrafish research, journals, and leading authors as reflected from the research output have been identified. USA is the most productive country with 8196 articles. The most frequently used keywords were also determined to gain insights about the research trends and some of the commonly used keywords other than zebrafish and Danio rerio are development, retina, and gene expression.

  11. Expression of gdnf and nos in adult zebrafish brain during the regeneration after spinal cord injury%成年斑马鱼脊髓损伤修复中脑gdnf 和nos 基因的表达

    Institute of Scientific and Technical Information of China (English)

    谢琳; 房萍; 林金飞; 潘洪超; 张帆; 申延琴

    2013-01-01

    成年斑马鱼(Danio rerio)具有很强的脊髓损伤后自主修复的能力,但目前其机制不明.为了研究斑马鱼中脑组织对脊髓再生的影响,文章应用成年斑马鱼脊髓损伤模型,采用实时定量PCR 方法和原位杂交技术,检测了斑马鱼脑中胶质细胞源性神经营养因子(gdnf)和一氧化氮合酶(nos)基因在脊髓损伤后4 h、12 h、6 d、11 d的表达情况,展示了这两种基因在斑马鱼脑内不同核团的动态表达变化.结果显示,成年斑马鱼脊髓损伤后,神经营养因子gdnf 基因在损伤急性期(4 h、12 h)和神经修复期(6 d、11 d)于斑马鱼脑内呈现显著性升高(P<0.05),而一氧化氮合酶基因nos 的表达于损伤急性期显著性升高 (P<0.05),随后下降,并在修复期 (11 d)显著降低(P<0.05).这表明,脊髓损伤后,高表达gdnf 基因同时低表达nos 基因的脑环境给脊髓损伤提供了良好的神经再生微环境,从而可能促进轴突的再生长及运动能力的恢复.%Recently, it is unclear about the mechanism of notable regenerated ability of adult zebrafish after spinal cord injury. To investigate the effects of brain on restoration from spinal cord injury, adult zebrafish spinal cord injury model was built and brain samples were dissected at different time points after the injury. Real-time quantitative PCR and in situ hybridization were applied to reveal the dynamics of glial cell line-derived neurotrophic factor (gdnf) and nitric oxide synthases (nos) mRNA expression in various regions of zebrafish brain. The results showed that, compared to sham group at each time points separately, the expression of gdnf mRNA in adult zebrafish brain during both acute phase (4 h and 12 h) and chronic phase of neuroregeneration (6 d and 11d) increased significantly (P<0.05). The expression of nos mRNA in zebrafish brain enhanced during acute phase, and then reduced to the level lower than the sham group during the chronic phase of neuroregeneration

  12. Zebrafish orthologs of human muscular dystrophy genes

    OpenAIRE

    Zon Leonard I; Zhou Yi; Pusack Timothy J; Beltre Rosanna; Vogel Emily D; Guyon Jeffrey R; Steffen Leta S; Kunkel Louis M

    2007-01-01

    Abstract Background Human muscular dystrophies are a heterogeneous group of genetic disorders which cause decreased muscle strength and often result in premature death. There is no known cure for muscular dystrophy, nor have all causative genes been identified. Recent work in the small vertebrate zebrafish Danio rerio suggests that mutation or misregulation of zebrafish dystrophy orthologs can also cause muscular degeneration phenotypes in fish. To aid in the identification of new causative g...

  13. Advances in the Study of Heart Development and Disease Using Zebrafish

    Science.gov (United States)

    Brown, Daniel R.; Samsa, Leigh Ann; Qian, Li; Liu, Jiandong

    2016-01-01

    Animal models of cardiovascular disease are key players in the translational medicine pipeline used to define the conserved genetic and molecular basis of disease. Congenital heart diseases (CHDs) are the most common type of human birth defect and feature structural abnormalities that arise during cardiac development and maturation. The zebrafish, Danio rerio, is a valuable vertebrate model organism, offering advantages over traditional mammalian models. These advantages include the rapid, stereotyped and external development of transparent embryos produced in large numbers from inexpensively housed adults, vast capacity for genetic manipulation, and amenability to high-throughput screening. With the help of modern genetics and a sequenced genome, zebrafish have led to insights in cardiovascular diseases ranging from CHDs to arrhythmia and cardiomyopathy. Here, we discuss the utility of zebrafish as a model system and summarize zebrafish cardiac morphogenesis with emphasis on parallels to human heart diseases. Additionally, we discuss the specific tools and experimental platforms utilized in the zebrafish model including forward screens, functional characterization of candidate genes, and high throughput applications. PMID:27335817

  14. Patterns of olfactory bulb neurogenesis in the adult zebrafish are altered following reversible deafferentation.

    Science.gov (United States)

    Trimpe, Darcy M; Byrd-Jacobs, Christine A

    2016-09-01

    Adult brain plasticity can be investigated using reversible methods that remove afferent innervation but allow return of sensory input. Repeated intranasal irrigation with Triton X-100 in adult zebrafish diminishes innervation to the olfactory bulb, resulting in a number of alterations in bulb structure and function, and cessation of the treatment allows for reinnervation and recovery. Using bromodeoxyuridine, Hu, and caspase-3 immunoreactivity we examined cell proliferation, differentiation, migration, and survival under conditions of acute and chronic deafferentation and reafferentation. Cell proliferation within the olfactory bulb was not influenced by acute or chronic deafferentation or reafferentation, but cell fate (including differentiation, migration, and/or survival of newly formed cells) was affected. We found that chronic deafferentation caused a bilateral increase in the number of newly formed cells that migrated into the bulb, although the amount of cell death of these new cells was significantly increased compared to untreated fish. Reafferentation also increased the number of newly formed cells migrating into both bulbs, suggesting that the deafferentation effect on cell fate was maintained. Reafferentation resulted in a decrease in newly formed cells that became neurons and, although death of newly formed cells was not altered from control levels, survival was reduced in relation to that seen in chronically deafferented fish. The potential effect of age on cell genesis was also examined. While the amount of cell migration into the olfactory bulbs was not affected by fish age, more of the newly formed cells became neurons in older fish. Younger fish displayed more cell death under conditions of chronic deafferentation. In sum, our results show that reversible deafferentation affects several aspects of cell fate, including cell differentiation, migration, and survival, and age of the fish influences the response to deafferentation. PMID:27343831

  15. Effects of Pro-Tex on zebrafish (Danio rerio) larvae, adult common carp (Cyprinus carpio) and adult yellowtail kingfish (Seriola lalandi)

    NARCIS (Netherlands)

    Boerrigter, J.G.J.; Vis, van de J.W.; Bos, van den R.; Abbink, W.; Spanings, T.; Zethof, J.; Louzao Martinez, L.; Andel, van W.F.M.; Lopez-Luna, J.; Flik, G.

    2014-01-01

    Aquaculture practices bring several stressful events to fish. Stressors not only activate the hypothalamus–pituitary–interrenal-axis, but also evoke cellular stress responses. Up-regulation of heat shock proteins (HSPs) is among the best studied mechanisms of the cellular stress response. An extract

  16. Development of Alginate Microspheres Containing Chuanxiong for Oral Administration to Adult Zebrafish

    OpenAIRE

    Li-Jen Lin; Chung-Jen Chiang; Yun-Peng Chao; Shulhn-Der Wang; Yu-Ting Chiou; Han-Yu Wang; Shung-Te Kao

    2016-01-01

    Oral administration of Traditional Chinese Medicine (TCM) by patients is the common way to treat health problems. Zebrafish emerges as an excellent animal model for the pharmacology investigation. However, the oral delivery system of TCM in zebrafish has not been established so far. This issue was addressed by development of alginate microparticles for oral delivery of chuanxiong, a TCM that displays antifibrotic and antiproliferative effects on hepatocytes. The delivery microparticles were p...

  17. Fast gene transfer into the adult zebrafish brain by herpes simplex virus 1 (HSV-1 and electroporation: methods and optogenetic applications

    Directory of Open Access Journals (Sweden)

    Ming eZou

    2014-05-01

    Full Text Available The zebrafish has various advantages as a model organism to analyze the structure and function of neural circuits but efficient viruses or other tools for fast gene transfer are lacking. We show that transgenes can be introduced directly into the adult zebrafish brain by herpes simplex type I viruses (HSV-1 or electroporation. We developed a new procedure to target electroporation to defined brain areas and identified promoters that produced strong long-term expression. The fast workflow of electroporation was exploited to express multiple channelrhodopsin-2 variants and genetically encoded calcium indicators in telencephalic neurons for measurements of neuronal activity and synaptic connectivity. The results demonstrate that HSV-1 and targeted electroporation are efficient tools for gene delivery into the zebrafish brain, similar to adeno-associated viruses and lentiviruses in other species. These methods fill an important gap in the spectrum of molecular tools for zebrafish and are likely to have a wide range of applications.

  18. Adult zebrafish intestine resection: a novel model of short bowel syndrome, adaptation, and intestinal stem cell regeneration

    Science.gov (United States)

    Schall, K. A.; Holoyda, K. A.; Grant, C. N.; Levin, D. E.; Torres, E. R.; Maxwell, A.; Pollack, H. A.; Moats, R. A.; Frey, M. R.; Darehzereshki, A.; Al Alam, D.; Lien, C.

    2015-01-01

    Loss of significant intestinal length from congenital anomaly or disease may lead to short bowel syndrome (SBS); intestinal failure may be partially offset by a gain in epithelial surface area, termed adaptation. Current in vivo models of SBS are costly and technically challenging. Operative times and survival rates have slowed extension to transgenic models. We created a new reproducible in vivo model of SBS in zebrafish, a tractable vertebrate model, to facilitate investigation of the mechanisms of intestinal adaptation. Proximal intestinal diversion at segment 1 (S1, equivalent to jejunum) was performed in adult male zebrafish. SBS fish emptied distal intestinal contents via stoma as in the human disease. After 2 wk, S1 was dilated compared with controls and villus ridges had increased complexity, contributing to greater villus epithelial perimeter. The number of intervillus pockets, the intestinal stem cell zone of the zebrafish increased and contained a higher number of bromodeoxyuridine (BrdU)-labeled cells after 2 wk of SBS. Egf receptor and a subset of its ligands, also drivers of adaptation, were upregulated in SBS fish. Igf has been reported as a driver of intestinal adaptation in other animal models, and SBS fish exposed to a pharmacological inhibitor of the Igf receptor failed to demonstrate signs of intestinal adaptation, such as increased inner epithelial perimeter and BrdU incorporation. We describe a technically feasible model of human SBS in the zebrafish, a faster and less expensive tool to investigate intestinal stem cell plasticity as well as the mechanisms that drive intestinal adaptation. PMID:26089336

  19. PAH toxicity at aqueous solubility in the fish embryo test with Danio rerio using passive dosing

    DEFF Research Database (Denmark)

    Fernqvist, Margit; Mayer, Philipp; Smith, Kilian;

    2014-01-01

    As part of the risk assessment process within REACh, prior to manufacturing and distribution of chemical substances their (eco)toxicological impacts have to be investigated. The fish embryo toxicity test (FET) with the zebrafish Danio rerio has gained a high significance as an in vitro alternative...

  20. Her4-positive population in the tectum opticum is proliferating neural precursors in the adult zebrafish brain.

    Science.gov (United States)

    Jung, Seung-Hyun; Kim, Hyung-Seok; Ryu, Jae-Ho; Gwak, Jung-Woo; Bae, Young-Ki; Kim, Cheol-Hee; Yeo, Sang-Yeob

    2012-06-01

    Previous studies have shown that Notch signaling not only regulates the number of early differentiating neurons, but also maintains proliferating neural precursors in the neural tube. Although it is well known that Notch signaling is closely related to the differentiation of adult neural stem cells, none of transgenic zebrafish provides a tool to figure out the relationship between Notch signaling and the differentiation of neural precursors. The goal of this study was to characterize Her4-positive cells by comparing the expression of a fluorescent Her4 reporter in Tg[her4-dRFP] animals with a GFAP reporter in Tg[gfap-GFP] adult zebrafish. BrdU incorporation indicated that dRFP-positive cells were proliferating and a double labeling assay revealed that a significant fraction of the Her4-dRFP positive population was also GFAP-GFP positive. Our observations suggest that a reporter line with Notch-dependent gene expression can provide a tool to examine proliferating neural precursors and/or neuronal/glial precursors in the development of the adult nervous system to examine the model in which Notch signaling maintains proliferating neural precursors in the neural tube.

  1. CLARITY and PACT-based imaging of adult zebrafish and mouse for whole-animal analysis of infections.

    Science.gov (United States)

    Cronan, Mark R; Rosenberg, Allison F; Oehlers, Stefan H; Saelens, Joseph W; Sisk, Dana M; Jurcic Smith, Kristen L; Lee, Sunhee; Tobin, David M

    2015-12-01

    Visualization of infection and the associated host response has been challenging in adult vertebrates. Owing to their transparency, zebrafish larvae have been used to directly observe infection in vivo; however, such larvae have not yet developed a functional adaptive immune system. Cells involved in adaptive immunity mature later and have therefore been difficult to access optically in intact animals. Thus, the study of many aspects of vertebrate infection requires dissection of adult organs or ex vivo isolation of immune cells. Recently, CLARITY and PACT (passive clarity technique) methodologies have enabled clearing and direct visualization of dissected organs. Here, we show that these techniques can be applied to image host-pathogen interactions directly in whole animals. CLARITY and PACT-based clearing of whole adult zebrafish and Mycobacterium tuberculosis-infected mouse lungs enables imaging of mycobacterial granulomas deep within tissue to a depth of more than 1 mm. Using established transgenic lines, we were able to image normal and pathogenic structures and their surrounding host context at high resolution. We identified the three-dimensional organization of granuloma-associated angiogenesis, an important feature of mycobacterial infection, and characterized the induction of the cytokine tumor necrosis factor (TNF) within the granuloma using an established fluorescent reporter line. We observed heterogeneity in TNF induction within granuloma macrophages, consistent with an evolving view of the tuberculous granuloma as a non-uniform, heterogeneous structure. Broad application of this technique will enable new understanding of host-pathogen interactions in situ. PMID:26449262

  2. CLARITY and PACT-based imaging of adult zebrafish and mouse for whole-animal analysis of infections

    Directory of Open Access Journals (Sweden)

    Mark R. Cronan

    2015-12-01

    Full Text Available Visualization of infection and the associated host response has been challenging in adult vertebrates. Owing to their transparency, zebrafish larvae have been used to directly observe infection in vivo; however, such larvae have not yet developed a functional adaptive immune system. Cells involved in adaptive immunity mature later and have therefore been difficult to access optically in intact animals. Thus, the study of many aspects of vertebrate infection requires dissection of adult organs or ex vivo isolation of immune cells. Recently, CLARITY and PACT (passive clarity technique methodologies have enabled clearing and direct visualization of dissected organs. Here, we show that these techniques can be applied to image host-pathogen interactions directly in whole animals. CLARITY and PACT-based clearing of whole adult zebrafish and Mycobacterium tuberculosis-infected mouse lungs enables imaging of mycobacterial granulomas deep within tissue to a depth of more than 1 mm. Using established transgenic lines, we were able to image normal and pathogenic structures and their surrounding host context at high resolution. We identified the three-dimensional organization of granuloma-associated angiogenesis, an important feature of mycobacterial infection, and characterized the induction of the cytokine tumor necrosis factor (TNF within the granuloma using an established fluorescent reporter line. We observed heterogeneity in TNF induction within granuloma macrophages, consistent with an evolving view of the tuberculous granuloma as a non-uniform, heterogeneous structure. Broad application of this technique will enable new understanding of host-pathogen interactions in situ.

  3. Automated visual tracking for studying the ontogeny of zebrafish swimming.

    Science.gov (United States)

    Fontaine, Ebraheem; Lentink, David; Kranenbarg, Sander; Müller, Ulrike K; van Leeuwen, Johan L; Barr, Alan H; Burdick, Joel W

    2008-04-01

    The zebrafish Danio rerio is a widely used model organism in studies of genetics, developmental biology, and recently, biomechanics. In order to quantify changes in swimming during all stages of development, we have developed a visual tracking system that estimates the posture of fish. Our current approach assumes planar motion of the fish, given image sequences taken from a top view. An accurate geometric fish model is automatically designed and fit to the images at each time frame. Our approach works across a range of fish shapes and sizes and is therefore well suited for studying the ontogeny of fish swimming, while also being robust to common environmental occlusions. Our current analysis focuses on measuring the influence of vertebra development on the swimming capabilities of zebrafish. We examine wild-type zebrafish and mutants with stiff vertebrae (stocksteif) and quantify their body kinematics as a function of their development from larvae to adult (mutants made available by the Hubrecht laboratory, The Netherlands). By tracking the fish, we are able to measure the curvature and net acceleration along the body that result from the fish's body wave. Here, we demonstrate the capabilities of the tracking system for the escape response of wild-type zebrafish and stocksteif mutant zebrafish. The response was filmed with a digital high-speed camera at 1500 frames s(-1). Our approach enables biomechanists and ethologists to process much larger datasets than possible at present. Our automated tracking scheme can therefore accelerate insight in the swimming behavior of many species of (developing) fish.

  4. Zebrafish: A complete animal model to enumerate the nanoparticle toxicity.

    Science.gov (United States)

    Chakraborty, Chiranjib; Sharma, Ashish Ranjan; Sharma, Garima; Lee, Sang-Soo

    2016-01-01

    Presently, nanotechnology is a multi-trillion dollar business sector that covers a wide range of industries, such as medicine, electronics and chemistry. In the current era, the commercial transition of nanotechnology from research level to industrial level is stimulating the world's total economic growth. However, commercialization of nanoparticles might offer possible risks once they are liberated in the environment. In recent years, the use of zebrafish (Danio rerio) as an established animal model system for nanoparticle toxicity assay is growing exponentially. In the current in-depth review, we discuss the recent research approaches employing adult zebrafish and their embryos for nanoparticle toxicity assessment. Different types of parameters are being discussed here which are used to evaluate nanoparticle toxicity such as hatching achievement rate, developmental malformation of organs, damage in gill and skin, abnormal behavior (movement impairment), immunotoxicity, genotoxicity or gene expression, neurotoxicity, endocrine system disruption, reproduction toxicity and finally mortality. Furthermore, we have also highlighted the toxic effect of different nanoparticles such as silver nanoparticle, gold nanoparticle, and metal oxide nanoparticles (TiO2, Al2O3, CuO, NiO and ZnO). At the end, future directions of zebrafish model and relevant assays to study nanoparticle toxicity have also been argued. PMID:27544212

  5. IDENTIFICATION AND PROMOTER ANALYSIS OF AN IFIT FAMILY GENE FROM ZEBRAFISH DANIO RERIO%斑马鱼一个IFIT家族基因的鉴定及启动子分析

    Institute of Scientific and Technical Information of China (English)

    刘颖; 张义兵; 刘庭凯; 桂建芳

    2012-01-01

    IFIT family consists of a group of interferon-induced proteins with Tetratricopeptide Repeat (TPR) motifs. Whereas there are four members in mammals, it is uncertain whether the same IFIT family members exist in fish and whether the fish homologues display the same expression pattern. Our previous report identified two genes from crucian carp Carassius auratus, which are similar to mammalian IFI58 and IFI56 and are induced by grass carp reovirus (GCRV) and interferon (IFN)-containing supernatant. However, unlike mammalian IFI56 gene, virus-induced expression of both genes is blocked by addition of cycloheximide (CHX), a potent inhibitor of protein synthesis. In order to further investigate whether there is an orthologue of mammalian IFI56 in zebrafish, we first searched zebrafish genome data by using mammalian IFI56 sequence. As expected, we identified a hypothetical zebrafish gene, named zebrafish IFIT-A gene, which contained a conserved gene structure similar to mammalian homologues. Zebrafish IFIT-A gene had the largest ORF that encoded a 429-amino-acid protein with conserved TPR motifs. Similar to mammalian IFI56, zebrafish IFIT-A gene was composed of an intron and two exons. RT-PCR showed that zebrafish IFIT-A mRNA was induced in ZFL cell by Poly I:C treatment. Sequence analysis of flanking region of zebrafish IFIT-A gene revealed a typical IFN-stimulated response element (ISRE), which was usually found in the promoters of Interferon Stimulated Genes (ISGs). Consistently, Poly I:C and recombinant crucian carp IFN protein were able to activate the activity of zebrafish IFIT-A promoter. Finally, overexpression of zebrafish IRF3 and IRF7 resulted in a significant increase in promoter activity of zebrafish IFIT-A gene. These data together provided evidence that zebrafish IFIT-A belonged to fish IFIT family and that fish IRF3 and IRF7 might play an important role in regulation of zebrafish IFIT-A expression.%IFIT家族由一类受干扰素诱导表达并具有TPR

  6. Pigment pattern evolution by differential deployment of neural crest and post-embryonic melanophore lineages in Danio fishes.

    Science.gov (United States)

    Quigley, Ian K; Turner, Jessica M; Nuckels, Richard J; Manuel, Joan L; Budi, Erine H; MacDonald, Erin L; Parichy, David M

    2004-12-01

    Latent precursors or stem cells of neural crest origin are present in a variety of post-embryonic tissues. Although these cells are of biomedical interest for roles in human health and disease, their potential evolutionary significance has been underappreciated. As a first step towards elucidating the contributions of such cells to the evolution of vertebrate form, we investigated the relative roles of neural crest cells and post-embryonic latent precursors during the evolutionary diversification of adult pigment patterns in Danio fishes. These pigment patterns result from the numbers and arrangements of embryonic melanophores that are derived from embryonic neural crest cells, as well as from post-embryonic metamorphic melanophores that are derived from latent precursors of presumptive neural crest origin. In the zebrafish D. rerio, a pattern of melanophore stripes arises during the larval-to-adult transformation by the recruitment of metamorphic melanophores from latent precursors. Using a comparative approach in the context of new phylogenetic data, we show that adult pigment patterns in five additional species also arise from metamorphic melanophores, identifying this as an ancestral mode of adult pigment pattern development. By contrast, superficially similar adult stripes of D. nigrofasciatus (a sister species to D. rerio) arise by the reorganization of melanophores that differentiated at embryonic stages, with a diminished contribution from metamorphic melanophores. Genetic mosaic and molecular marker analyses reveal evolutionary changes that are extrinsic to D. nigrofasciatus melanophore lineages, including a dramatic reduction of metamorphic melanophore precursors. Finally, interspecific complementation tests identify a candidate genetic pathway for contributing to the evolutionary reduction in metamorphic melanophores and the increased contribution of early larval melanophores to D. nigrofasciatus adult pigment pattern development. These results

  7. Development of Alginate Microspheres Containing Chuanxiong for Oral Administration to Adult Zebrafish.

    Science.gov (United States)

    Lin, Li-Jen; Chiang, Chung-Jen; Chao, Yun-Peng; Wang, Shulhn-Der; Chiou, Yu-Ting; Wang, Han-Yu; Kao, Shung-Te

    2016-01-01

    Oral administration of Traditional Chinese Medicine (TCM) by patients is the common way to treat health problems. Zebrafish emerges as an excellent animal model for the pharmacology investigation. However, the oral delivery system of TCM in zebrafish has not been established so far. This issue was addressed by development of alginate microparticles for oral delivery of chuanxiong, a TCM that displays antifibrotic and antiproliferative effects on hepatocytes. The delivery microparticles were prepared from gelification of alginate containing various levels of chuanxiong. The chuanxiong-encapsulated alginate microparticles were characterized for their solubility, structure, encapsulation efficiency, the cargo release profile, and digestion in gastrointestinal tract of zebrafish. Encapsulation of chuanxiong resulted in more compact structure and the smaller size of microparticles. The release rate of chuanxiong increased for alginate microparticles carrying more chuanxiong in simulated intestinal fluid. This remarkable feature ensures the controlled release of encapsulated cargos in the gastrointestinal tract of zebrafish. Moreover, chuanxiong-loaded alginate microparticles were moved to the end of gastrointestinal tract after oral administration for 6 hr and excreted from the body after 16 hr. Therefore, our developed method for oral administration of TCM in zebrafish is useful for easy and rapid evaluation of the drug effect on disease. PMID:27403425

  8. Development of Alginate Microspheres Containing Chuanxiong for Oral Administration to Adult Zebrafish

    Directory of Open Access Journals (Sweden)

    Li-Jen Lin

    2016-01-01

    Full Text Available Oral administration of Traditional Chinese Medicine (TCM by patients is the common way to treat health problems. Zebrafish emerges as an excellent animal model for the pharmacology investigation. However, the oral delivery system of TCM in zebrafish has not been established so far. This issue was addressed by development of alginate microparticles for oral delivery of chuanxiong, a TCM that displays antifibrotic and antiproliferative effects on hepatocytes. The delivery microparticles were prepared from gelification of alginate containing various levels of chuanxiong. The chuanxiong-encapsulated alginate microparticles were characterized for their solubility, structure, encapsulation efficiency, the cargo release profile, and digestion in gastrointestinal tract of zebrafish. Encapsulation of chuanxiong resulted in more compact structure and the smaller size of microparticles. The release rate of chuanxiong increased for alginate microparticles carrying more chuanxiong in simulated intestinal fluid. This remarkable feature ensures the controlled release of encapsulated cargos in the gastrointestinal tract of zebrafish. Moreover, chuanxiong-loaded alginate microparticles were moved to the end of gastrointestinal tract after oral administration for 6 hr and excreted from the body after 16 hr. Therefore, our developed method for oral administration of TCM in zebrafish is useful for easy and rapid evaluation of the drug effect on disease.

  9. Development of Alginate Microspheres Containing Chuanxiong for Oral Administration to Adult Zebrafish

    Science.gov (United States)

    Lin, Li-Jen; Chiang, Chung-Jen; Chao, Yun-Peng; Wang, Shulhn-Der; Chiou, Yu-Ting; Wang, Han-Yu; Kao, Shung-Te

    2016-01-01

    Oral administration of Traditional Chinese Medicine (TCM) by patients is the common way to treat health problems. Zebrafish emerges as an excellent animal model for the pharmacology investigation. However, the oral delivery system of TCM in zebrafish has not been established so far. This issue was addressed by development of alginate microparticles for oral delivery of chuanxiong, a TCM that displays antifibrotic and antiproliferative effects on hepatocytes. The delivery microparticles were prepared from gelification of alginate containing various levels of chuanxiong. The chuanxiong-encapsulated alginate microparticles were characterized for their solubility, structure, encapsulation efficiency, the cargo release profile, and digestion in gastrointestinal tract of zebrafish. Encapsulation of chuanxiong resulted in more compact structure and the smaller size of microparticles. The release rate of chuanxiong increased for alginate microparticles carrying more chuanxiong in simulated intestinal fluid. This remarkable feature ensures the controlled release of encapsulated cargos in the gastrointestinal tract of zebrafish. Moreover, chuanxiong-loaded alginate microparticles were moved to the end of gastrointestinal tract after oral administration for 6 hr and excreted from the body after 16 hr. Therefore, our developed method for oral administration of TCM in zebrafish is useful for easy and rapid evaluation of the drug effect on disease.

  10. Advances in understanding the mechanism of zebrafish heart regeneration

    Directory of Open Access Journals (Sweden)

    Kazu Kikuchi

    2014-11-01

    Full Text Available The adult mammalian heart was once believed to be a post-mitotic organ without any capacity for regeneration, but recent findings have challenged this dogma. A modified view assigns the mammalian heart a measurable capacity for regeneration throughout its lifetime, with the implication that endogenous regenerative capacity can be therapeutically stimulated in the injury setting. Although extremely limited in adult mammals, the natural capacity for organ regeneration is a conserved trait in certain vertebrates. Urodele amphibians and teleosts are well-known examples of such animals that can efficiently regenerate various organs including the heart as adults. By understanding how these animals regenerate a damaged heart, one might obtain valuable insights into how regeneration can be augmented in injured human hearts. Among the regenerative vertebrate models, the teleost zebrafish, Danio rerio, is arguably the best characterized with respect to cardiac regenerative responses. Knowledge is still limited, but a decade of research in this model has led to results that may help to understand how cardiac regeneration is naturally stimulated and maintained. This review surveys recent advances in the field and discusses current understanding of the endogenous mechanisms of cardiac regeneration in zebrafish.

  11. Taxonomy Icon Data: Danio rerio [Taxonomy Icon

    Lifescience Database Archive (English)

    Full Text Available io_NL.png Danio_rerio_S.png Danio_rerio_NS.png http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Danio+rerio&...t=L http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Danio+rerio&t=NL http://biosciencedbc.jp/taxonomy_icon/...icon.cgi?i=Danio+rerio&t=S http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Danio...+rerio&t=NS http://togodb.biosciencedbc.jp/togodb/view/taxonomy_icon_comment_en?species_id=92 ...

  12. Cognitive aging in zebrafish.

    Directory of Open Access Journals (Sweden)

    Lili Yu

    Full Text Available BACKGROUND: Age-related impairments in cognitive functions represent a growing clinical and social issue. Genetic and behavioral characterization of animal models can provide critical information on the intrinsic and environmental factors that determine the deterioration or preservation of cognitive abilities throughout life. METHODOLOGY/PRINCIPAL FINDINGS: Behavior of wild-type, mutant and gamma-irradiated zebrafish (Danio rerio was documented using image-analysis technique. Conditioned responses to spatial, visual and temporal cues were investigated in young, middle-aged and old animals. The results demonstrate that zebrafish aging is associated with changes in cognitive responses to emotionally positive and negative experiences, reduced generalization of adaptive associations, increased stereotypic and reduced exploratory behavior and altered temporal entrainment. Genetic upregulation of cholinergic transmission attenuates cognitive decline in middle-aged achesb55/+ mutants, compared to wild-type siblings. In contrast, the genotoxic stress of gamma-irradiation accelerates the onset of cognitive impairment in young zebrafish. CONCLUSIONS/SIGNIFICANCE: These findings would allow the use of powerful molecular biological resources accumulated in the zebrafish field to address the mechanisms of cognitive senescence, and promote the search for therapeutic strategies which may attenuate age-related cognitive decline.

  13. In vitro neutralization of viral hemorrhagic septicemia virus by plasma from immunized zebrafish

    NARCIS (Netherlands)

    Chinchilla, B.; Gomez-Casado, E.; Encinas, P.; Falco Gracia, J.A.; Estepa, A.; Coll, J.

    2013-01-01

    We studied humoral long-term adaptive viral neutralization responses in zebrafish (Danio rerio), an increasingly useful vertebrate model for viral diseases actually limited by the absence of standardized anti-zebrafish immunoglobulin M (IgM) antibodies. We established an alternative method, similar

  14. Identification of Estrogen Target Genes during Zebrafish Embryonic Development through Transcriptomic Analysis

    Science.gov (United States)

    Estrogen signaling is important for vertebrate embryonic development. Here we have used zebrafish (Danio rerio) as a vertebrate model to analyze estrogen signaling during development. Zebrafish embryos were exposed to 1 μM 17β-estradiol (E2) or vehicle from 3 hours to 4 days post...

  15. In vivo spectroscopic photoacoustic tomography imaging of a far red fluorescent protein expressed in the exocrine pancreas of adult zebrafish

    Science.gov (United States)

    Liu, Mengyang; Schmitner, Nicole; Sandrian, Michelle G.; Zabihian, Behrooz; Hermann, Boris; Salvenmoser, Willi; Meyer, Dirk; Drexler, Wolfgang

    2014-03-01

    Fluorescent proteins brought a revolution in life sciences and biological research in that they make a powerful tool for researchers to study not only the structural and morphological information, but also dynamic and functional information in living cells and organisms. While green fluorescent proteins (GFP) have become a common labeling tool, red-shifted or even near infrared fluorescent proteins are becoming the research focus due to the fact that longer excitation wavelengths are more suitable for deep tissue imaging. In this study, E2-Crimson, a far red fluorescent protein whose excitation wavelength is 611 nm, was genetically expressed in the exocrine pancreas of adult zebrafish. Using spectroscopic all optical detection photoacoustic tomography, we mapped the distribution of E2-Crimson in 3D after imaging the transgenic zebrafish in vivo using two different wavelengths. With complementary morphological information provided by imaging the same fish using a spectral domain optical coherence tomography system, the E2-Crimson distribution acquired from spectroscopic photoacoustic tomography was confirmed in 2D by epifluorescence microscopy and in 3D by histology. To the authors' knowledge, this is the first time a far red fluorescent protein is imaged in vivo by spectroscopic photoacoustic tomography. Due to the regeneration feature of zebrafish pancreas, this work preludes the longitudinal studies of animal models of diseases such as pancreatitis by spectroscopic photoacoustic tomography. Since the effective penetration depth of photoacoustic tomography is beyond the transport mean free path length, other E2-Crimson labeled inner organs will also be able to be studied dynamically using spectroscopic photoacoustic tomography.

  16. Melanophore migration and survival during zebrafish adult pigment stripe development require the immunoglobulin superfamily adhesion molecule Igsf11.

    Directory of Open Access Journals (Sweden)

    Dae Seok Eom

    Full Text Available The zebrafish adult pigment pattern has emerged as a useful model for understanding the development and evolution of adult form as well as pattern-forming mechanisms more generally. In this species, a series of horizontal melanophore stripes arises during the larval-to-adult transformation, but the genetic and cellular bases for stripe formation remain largely unknown. Here, we show that the seurat mutant phenotype, consisting of an irregular spotted pattern, arises from lesions in the gene encoding Immunoglobulin superfamily member 11 (Igsf11. We find that Igsf11 is expressed by melanophores and their precursors, and we demonstrate by cell transplantation and genetic rescue that igsf11 functions autonomously to this lineage in promoting adult stripe development. Further analyses of cell behaviors in vitro, in vivo, and in explant cultures ex vivo demonstrate that Igsf11 mediates adhesive interactions and that mutants for igsf11 exhibit defects in both the migration and survival of melanophores and their precursors. These findings identify the first in vivo requirements for igsf11 as well as the first instance of an immunoglobulin superfamily member functioning in pigment cell development and patterning. Our results provide new insights into adult pigment pattern morphogenesis and how cellular interactions mediate pattern formation.

  17. Zebrafish as an animal model to study ion homeostasis

    OpenAIRE

    Hwang, Pung-Pung; Chou, Ming-Yi

    2013-01-01

    Zebrafish (Danio rerio) possesses several advantages as an experimental organism, including the applicability of molecular tools, ease of in vivo cellular observation and functional analysis, and rapid embryonic development, making it an emerging model for the study of integrative and regulatory physiology and, in particular, the epithelial transport associated with body fluid ionic homeostasis. Zebrafish inhabits a hypotonic freshwater environment, and as such, the gills (or the skin, during...

  18. A crystal-clear zebrafish for in vivo imaging

    OpenAIRE

    Antinucci, Paride; Hindges, Robert

    2016-01-01

    The larval zebrafish (Danio rerio) is an excellent vertebrate model for in vivo imaging of biological phenomena at subcellular, cellular and systems levels. However, the optical accessibility of highly pigmented tissues, like the eyes, is limited even in this animal model. Typical strategies to improve the transparency of zebrafish larvae require the use of either highly toxic chemical compounds (e.g. 1-phenyl-2-thiourea, PTU) or pigmentation mutant strains (e.g. casper mutant). To date none ...

  19. Zebrafish as animal model for aquaculture nutrition research

    OpenAIRE

    Ulloa, Pilar E.; Medrano, Juan F.; Feijoo, Carmen G.

    2014-01-01

    The aquaculture industry continues to promote the diversification of ingredients used in aquafeed in order to achieve a more sustainable aquaculture production system. The evaluation of large numbers of diets in aquaculture species is costly and requires time-consuming trials in some species. In contrast, zebrafish (Danio rerio) can solve these drawbacks as an experimental model, and represents an ideal organism to carry out preliminary evaluation of diets. In addition, zebrafish has a sequen...

  20. Identification of an evolutionarily conserved regulatory element of the zebrafish col2a1a gene

    OpenAIRE

    Dale, Rodney M.; Topczewski, Jacek

    2011-01-01

    Zebrafish (Danio rerio) is an excellent model organism for the study of vertebrate development including skeletogenesis. Studies of mammalian cartilage formation were greatly advanced through the use of a cartilage specific regulatory element of the Collagen type II alpha 1 (Col2a1) gene. In an effort to isolate such an element in zebrafish, we compared the expression of two col2a1 homologues and found that expression of col2a1b, a previously uncharacterized zebrafish homologue, only partiall...

  1. Revealing details: whole mount microRNA in situ hybridization protocol for zebrafish embryos and adult tissues

    Directory of Open Access Journals (Sweden)

    Anne Karine Lagendijk

    2012-04-01

    Non-coding microRNA (miRNA molecules bind their target mRNAs and thereby modulate the amount of protein produced. To understand the significance of a potential miRNA-mRNA interaction, temporal and spatial information on miRNA and mRNA expression is essential. Here, we provide a detailed protocol for miRNA whole mount in situ hybridization. We introduce the use of Morpholino based oligos as antisense probes for miRNA detection, in addition to the current “gold standard” locked nucleic acid (LNA probes. Furthermore we have modified existing miRNA in situ protocols thereby improving both sensitivity and resolution of miRNA visualization in whole zebrafish embryos and adult tissues.

  2. Organ-Specific and Size-Dependent Ag Nanoparticle Toxicity in Gills and Intestines of Adult Zebrafish.

    Science.gov (United States)

    Osborne, Olivia J; Lin, Sijie; Chang, Chong Hyun; Ji, Zhaoxia; Yu, Xuechen; Wang, Xiang; Lin, Shuo; Xia, Tian; Nel, André E

    2015-10-27

    We studied adult zebrafish to determine whether the size of 20 and 110 nm citrate-coated silver nanoparticles (AgC NPs) differentially impact the gills and intestines, known target organs for Ag toxicity in fish. Following exposure for 4 h, 4 days, or 4 days plus a 7 day depuration period, we obtained different toxicokinetic profiles for different particle sizes, as determined by Ag content of the tissues. Ionic AgNO3 served as a positive control. The gills showed a significantly higher Ag content for the 20 nm particles at 4 h and 4 days than the 110 nm particles, while the values were more similar in the intestines. Both particle types were retained in the intestines even after depuration. These toxicokinetics were accompanied by striking size-dependent differences in the ultrastructural features and histopathology in the target organs in response to the particulates. Ag staining of the gills and intestines confirmed prominent Ag deposition in the basolateral membranes for the 20 nm but not for the 110 nm particles. Furthermore, it was possible to link the site of tissue deposition to disruption of the Na(+)/K(+) ion channel, which is also localized to the basolateral membrane. This was confirmed by a reduction in ATPase activity and immunohistochemical detection of the α subunit of this channel in both target organs, with the 20 nm particles causing significantly higher inhibition and disruption than the larger size particles or AgNO3. These results demonstrate the importance of particle size in determining the hazardous impact of AgNPs in the gills and intestines of adult zebrafish.

  3. The cytochrome P450 2AA gene cluster in zebrafish (Danio rerio): Expression of CYP2AA1 and CYP2AA2 and response to phenobarbital-type inducers

    Energy Technology Data Exchange (ETDEWEB)

    Kubota, Akira [Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543 (United States); Bainy, Afonso C.D. [Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543 (United States); Departamento de Bioquímica, CCB, Universidade Federal de Santa Catarina, Florianopolis, SC 88040-900 (Brazil); Woodin, Bruce R.; Goldstone, Jared V. [Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543 (United States); Stegeman, John J., E-mail: jstegeman@whoi.edu [Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543 (United States)

    2013-10-01

    The cytochrome P450 (CYP) 2 gene family is the largest and most diverse CYP gene family in vertebrates. In zebrafish, we have identified 10 genes in a new subfamily, CYP2AA, which does not show orthology to any human or other mammalian CYP genes. Here we report evolutionary and structural relationships of the 10 CYP2AA genes and expression of the first two genes, CYP2AA1 and CYP2AA2. Parsimony reconstruction of the tandem duplication pattern for the CYP2AA cluster suggests that CYP2AA1, CYP2AA2 and CYP2AA3 likely arose in the earlier duplication events and thus are most diverged in function from the other CYP2AAs. On the other hand, CYP2AA8 and CYP2AA9 are genes that arose in the latest duplication event, implying functional similarity between these two CYPs. A molecular model of CYP2AA1 showing the sequence conservation across the CYP2AA cluster reveals that the regions with the highest variability within the cluster map onto CYP2AA1 near the substrate access channels, suggesting differing substrate specificities. Zebrafish CYP2AA1 transcript was expressed predominantly in the intestine, while CYP2AA2 was most highly expressed in the kidney, suggesting differing roles in physiology. In the liver CYP2AA2 expression but not that of CYP2AA1, was increased by 1,4-bis [2-(3,5-dichloropyridyloxy)] benzene (TCPOBOP) and, to a lesser extent, by phenobarbital (PB). In contrast, pregnenolone 16α-carbonitrile (PCN) increased CYP2AA1 expression, but not CYP2AA2 in the liver. The results identify a CYP2 subfamily in zebrafish that includes genes apparently induced by PB-type chemicals and PXR agonists, the first concrete in vivo evidence for a PB-type response in fish. - Highlights: • A tandemly duplicated cluster of ten CYP2AA genes was described in zebrafish. • Parsimony and duplication analyses suggest pathways to CYP2AA diversity. • Homology models reveal amino acid positions possibly related to functional diversity. • The CYP2AA locus does not share synteny with

  4. Effects of exposure to nonylphenol on courtship behavior and reproductive success of zebrafish(Danio rerio)%壬基酚暴露对斑马鱼求偶行为与繁殖成功率的影响

    Institute of Scientific and Technical Information of China (English)

    夏继刚; 牛翠娟

    2010-01-01

    壬基酚(NP)是普遍存在于水生生态系统中的一种环境内分泌干扰物.研究了不同浓度下(0,0.1,1,10,50,100 μg/L)NP暴露对斑马鱼(Danio rerio)求偶行为与繁殖成功率的影响.结果表明,NP暴露对斑马龟求偶行为与繁殖成功率影响显著,100μg/L NP暴露显著减少斑马龟求偶时间、降低产卵量与受精率(P<0.05).斑马鱼产卵量与求偶总时间、平均每次求偶时间、长于5 s的求偶时间显著正相关(P<0.05),与求偶频率不相关(P=0.951).NP暴露可能通过影响斑马鱼求偶时间,进而影响产卵量.斑马鱼求偶时间有望作为评估水体NP污染有效的生物标记.

  5. 全氟辛烷磺酸(PFOS)急性暴露对斑马鱼鳃显微结构的影响%Acute Effects of Periluorooctane Sulfonate on Microstructure of the Gill of Zebrafish(Danio rerio)

    Institute of Scientific and Technical Information of China (English)

    胡芹; 周珍; 周群芳; 张捷; 梁勇

    2009-01-01

    采用光镜和电镜的方法,探讨了高浓度全氟辛烷磺酸(PFOS)急性暴露对斑马鱼(Danio rerio)鳃显微结构的影响.暴露组PFOS浓度分别为0.5、1、2mg·L-1,同时设对照组,连续暴露7d,取鳃制备石蜡切片,进行光镜和扫描电镜观察.结果表明,7d后PFOS暴露组斑马鱼鳃部均有不同程度的损伤,石蜡切片上可观察到暴露组鱼鳃卜皮细胞坏死脱落,鳃小片断裂或融合,并伴有鳃丝充血,且病变程度随FFOS浓度的升高而加重;扫描电镜下可观察到暴露组鱼鳃鳃丝表而分泌物增多,鳃丝细胞脱落或水肿,鳃小片前端细胞破损.高浓度PFOS急性暴露可在短期内对斑马鱼鳃组织造成严重损伤,且损伤程度存在剂量依赖效应.

  6. Effects of butachlor on estrogen receptor, vitellogenin and P450 aromatase gene expression in the early life stage of zebrafish.

    Science.gov (United States)

    Chang, Juhua; Gui, Wenjun; Wang, Minghua; Zhu, Guonian

    2012-01-01

    Butachlor has adverse effects on fecundity and disrupts sex hormone homeostasis in adult zebrafish, but the underlying molecular mechanisms are still unclear. In the present study, zebrafish (Danio rerio) embryos were exposed to various concentrations of butachlor from 2 h post-fertilization (hpf) to 30 days post-fertilization (dpf). The transcription of genes involved estrogen receptors (ERα, ERβ1 and ERβ2), vitellogenins (VTG I and II), and cytochrome P450 aromatase (CYP19a) was analyzed by real-time quantitative PCR. The results showed that there was no significant alteration in the expression of VTGI, ERα, ERβ1, ERβ2 and CYP19a after 30 days of butachlor exposure, whereas the transcription of VTG II gene was significantly up-regulated in zebrafish exposed to 100 μg/L butachlor. It is suggested that butachlor may be a weak estrogen, and more endpoints need to be investigated to assess the effects of butachlor on the hypothalamus-pituitary-gonadal axis of zebrafish.

  7. Zebrafish stripes as a model for vertebrate colour pattern formation.

    Science.gov (United States)

    Singh, Ajeet Pratap; Nüsslein-Volhard, Christiane

    2015-01-19

    Colour patterns are prominent features of many animals and have important functions in communication, such as camouflage, kin recognition and mate choice. As targets for natural as well as sexual selection, they are of high evolutionary significance. The molecular mechanisms underlying colour pattern formation in vertebrates are not well understood. Progress in transgenic tools, in vivo imaging and the availability of a large collection of mutants make the zebrafish (Danio rerio) an attractive model to study vertebrate colouration. Zebrafish display golden and blue horizontal stripes that form during metamorphosis as mosaics of yellow xanthophores, silvery or blue iridophores and black melanophores in the hypodermis. Lineage tracing revealed the origin of the adult pigment cells and their individual cellular behaviours during the formation of the striped pattern. Mutant analysis indicated that interactions between all three pigment cell types are required for the formation of the pattern, and a number of cell surface molecules and signalling systems have been identified as mediators of these interactions. The understanding of the mechanisms that underlie colour pattern formation is an important step towards deciphering the genetic basis of variation in evolution. PMID:25602311

  8. Effects of embryonic ethanol exposure at low doses on neuronal development, voluntary ethanol consumption and related behaviors in larval and adult zebrafish: Role of hypothalamic orexigenic peptides.

    Science.gov (United States)

    Sterling, M E; Chang, G-Q; Karatayev, O; Chang, S Y; Leibowitz, S F

    2016-05-01

    Embryonic exposure to ethanol is known to affect neurochemical systems in rodents and increase alcohol drinking and related behaviors in humans and rodents. With zebrafish emerging as a powerful tool for uncovering neural mechanisms of numerous diseases and exhibiting similarities to rodents, the present report building on our rat studies examined in zebrafish the effects of embryonic ethanol exposure on hypothalamic neurogenesis, expression of orexigenic neuropeptides, and voluntary ethanol consumption and locomotor behaviors in larval and adult zebrafish, and also effects of central neuropeptide injections on these behaviors affected by ethanol. At 24h post-fertilization, zebrafish embryos were exposed for 2h to ethanol, at low concentrations of 0.25% and 0.5%, in the tank water. Embryonic ethanol compared to control dose-dependently increased hypothalamic neurogenesis and the proliferation and expression of the orexigenic peptides, galanin (GAL) and orexin (OX), in the anterior hypothalamus. These changes in hypothalamic peptide neurons were accompanied by an increase in voluntary consumption of 10% ethanol-gelatin and in novelty-induced locomotor and exploratory behavior in adult zebrafish and locomotor activity in larvae. After intracerebroventricular injection, these peptides compared to vehicle had specific effects on these behaviors altered by ethanol, with GAL stimulating consumption of 10% ethanol-gelatin more than plain gelatin food and OX stimulating novelty-induced locomotor behavior while increasing intake of food and ethanol equally. These results, similar to those obtained in rats, suggest that the ethanol-induced increase in genesis and expression of these hypothalamic peptide neurons contribute to the behavioral changes induced by embryonic exposure to ethanol. PMID:26778786

  9. Induction of Female-to-Male Sex Change in Adult Zebrafish by Aromatase Inhibitor Treatment

    Science.gov (United States)

    Takatsu, Kanae; Miyaoku, Kaori; Roy, Shimi Rani; Murono, Yuki; Sago, Tomohiro; Itagaki, Hideyuki; Nakamura, Masaru; Tokumoto, Toshinobu

    2013-12-01

    This study investigated whether undifferentiated germ and/or somatic stem cells remain in the differentiated ovary of a species that does not undergo sex changes under natural conditions and retain their sexual plasticity. The effect of aromatase inhibitor (AI)-treatment on sexually mature female zebrafish was examined. A 5-month AI treatment caused retraction of the ovaries after which testes-like organs appeared, and cyst structures filled with spermatozoa-like cells were observed in sections of these tissues. Electron microscopic observations revealed that these cells appeared as large sperm heads without tails. Sperm formation was re-examined after changing the diet to an AI-free food. A large number of normal sperm were obtained after eight weeks, and no formation of ovarian tissue was observed. Artificial fertilization using sperm from the sex-changed females was successful. These results demonstrated that sex plasticity remains in the mature ovaries of this species.

  10. Development of social behavior in young zebrafish

    OpenAIRE

    Elena eDreosti; Gonçalo eLopes; Adam Raymond Kampff; Wilson, Stephen W.

    2015-01-01

    Adult zebrafish are robustly social animals whereas larva is not. We designed an assay to determine at what stage of development zebrafish begin to interact with and prefer other fish. One week old zebrafish do not show significant social preference whereas most 3 weeks old zebrafish strongly prefer to remain in a compartment where they can view conspecifics. However, for some individuals, the presence of conspecifics drives avoidance instead of attraction. Social preference is dependent on v...

  11. Development of social behaviour in young zebrafish

    OpenAIRE

    Dreosti, E.; Lopes, G.; Kampff, A. R.; Wilson, S W

    2015-01-01

    Adult zebrafish are robustly social animals whereas larva is not. We designed an assay to determine at what stage of development zebrafish begin to interact with and prefer other fish. One week old zebrafish do not show significant social preference whereas most 3 weeks old zebrafish strongly prefer to remain in a compartment where they can view conspecifics. However, for some individuals, the presence of conspecifics drives avoidance instead of attraction. Social preference is dependent on v...

  12. Neurochemical measurements in the zebrafish brain

    OpenAIRE

    Lauren eJones; James eMcCutcheon; Andrew eYoung; William eNorton

    2015-01-01

    The zebrafish is an ideal model organism for behavioural genetics and neuroscience. The high conservation of genes and neurotransmitter pathways between zebrafish and other vertebrates permits the translation of research between species. Zebrafish behaviour can be studied at both larval and adult stages and recent research has begun to establish zebrafish models for human disease. Fast scan cyclic voltammetry (FSCV) is an electrochemical technique that permits the detection of neurotransmitte...

  13. Metal uptake and acute toxicity in zebrafish: Common mechanisms across multiple metals

    Energy Technology Data Exchange (ETDEWEB)

    Alsop, Derek, E-mail: alsopde@mcmaster.ca [Department of Biology, McMaster University, 1280 Main St. W., Hamilton, ON L8S 4K1 (Canada); Wood, Chris M. [Department of Biology, McMaster University, 1280 Main St. W., Hamilton, ON L8S 4K1 (Canada)

    2011-10-15

    All metals tested reduced calcium uptake in zebrafish larvae. However, it was whole body sodium loss that was functionally related to toxicity. The zebrafish larvae acute toxicity assay save time, space and resources. - Abstract: Zebrafish larvae (Danio rerio) were used to examine the mechanisms of action and acute toxicities of metals. Larvae had similar physiological responses and sensitivities to waterborne metals as adults. While cadmium and zinc have previously been shown to reduce Ca{sup 2+} uptake, copper and nickel also decreased Ca{sup 2+} uptake, suggesting that the epithelial transport of all these metals is through Ca{sup 2+} pathways. However, exposure to cadmium, copper or nickel for up to 48 h had little or no effect on total whole body Ca{sup 2+} levels, indicating that the reduction of Ca{sup 2+} uptake is not the acute toxic mechanism of these metals. Instead, mortalities were effectively related to whole body Na{sup +}, which decreased up to 39% after 48 h exposures to different metals around their respective 96 h LC50s. Decreases in whole body K{sup +} were also observed, although they were not as pronounced or frequent as Na{sup +} losses. None of the metals tested inhibited Na{sup +} uptake in zebrafish (Na{sup +} uptake was in fact increased with exposure) and the observed losses of Na{sup +}, K{sup +}, Ca{sup 2+} and Mg{sup 2+} were proportional to the ionic gradients between the plasma and water, indicating diffusive ion loss with metal exposure. This study has shown that there is a common pathway for metal uptake and a common mechanism of acute toxicity across groups of metals in zebrafish. The disruption of ion uptake accompanying metal exposure does not appear to be responsible for the acute toxicity of metals, as has been previously suggested, but rather the toxicity is instead due to total ion loss (predominantly Na{sup +}).

  14. Expression of the zebrafish intermediate neurofilament Nestin in the developing nervous system and in neural proliferation zones at postembryonic stages

    Directory of Open Access Journals (Sweden)

    Driever Wolfgang

    2007-07-01

    Full Text Available Abstract Background The intermediate filament Nestin has been reported as a marker for stem cells and specific precursor cell populations in the developing mammalian central nervous system (CNS. Nestin expressing precursors may give rise to neurons and glia. Mouse nestin expression starts at the onset of neurulation in the neuroectodermal cells and is dramatically down regulated when progenitor cells differentiate and become postmitotic. It has been reported that in the adult zebrafish (Danio rerio active neurogenesis continues in all major subdivisions of the CNS, however few markers for zebrafish precursors cells are known, and Nestin has not been described in zebrafish. Results We cloned a zebrafish nestin gDNA fragment in order to find a marker for precursor cells in the developing and postembryonic brain. Phylogenetic tree analysis reveals that this zebrafish ortholog clusters with Nestin sequences from other vertebrates but not with other intermediate filament proteins. We analyzed nestin expression from gastrula stage to 4 day larvae, and in post-embryonic brains. We found broad expression in the neuroectoderm during somitogenesis. In the larvae, nestin expression progressively becomes restricted to all previously described proliferative zones of the developing and postembryonic central nervous system. nestin expressing cells of the forebrain also express PCNA during late embryogenesis, identifying them as proliferating precursor or neural stem cells. nestin is also expressed in the cranial ganglia, in mesodermal precursors of muscle cells, and in cranial mesenchymal tissue. Conclusion Our data demonstrate that in zebrafish, like in mammals, the expression of the intermediated neurofilament nestin gene may serve as a marker for stem cells and proliferating precursors in the developing embryonic nervous system as well as in the postembryonic brain.

  15. A multivariate assessment of innate immune-related gene expressions due to exposure to low concentration individual and mixtures of four kinds of heavy metals on zebrafish (Danio rerio) embryos.

    Science.gov (United States)

    Cobbina, Samuel Jerry; Xu, Hai; Zhao, Ting; Mao, Guanghua; Zhou, Zhaoxiang; Wu, Xueshan; Liu, Hongyang; Zou, Yanmin; Wu, Xiangyang; Yang, Liuqing

    2015-12-01

    Concerns over the potential health effects of mixtures of low concentration heavy metals on living organisms keep growing by the day. However, the toxicity of low concentration metal mixtures on the immune system of fish species has rarely been investigated. In this study, the zebrafish model was employed to investigate the effect on innate immune and antioxidant-related gene expressions, on exposure to environmentally relevant concentrations of individual and mixtures of Pb (0.01 mg/L), Hg (0.001 mg/L), As (0.01 mg/L) and Cd (0.005 mg/L). Messenger-RNA (mRNA) levels of IL1β, TNF-α, IFNγ, Mx, Lyz, C3B and CXCL-Clc which are closely associated with the innate immune system were affected after exposing zebrafish embryos to metals for 120 h post fertilization (hpf). Individual and mixtures of metals exhibited different potentials to modulate innate-immune gene transcription. IL1β genes were significantly up regulated on exposure to Pb + As (2.01-fold) and inhibited on exposure to Pb + Hg + Cd (0.13-fold). TNF-α was significantly inhibited on exposure to As (0.40-fold) and Pb + As (0.32-fold) compared to control. Metal mixtures generally up regulated IFNγ compared to individual metals. Additionally, antioxidant genes were affected, as CAT and GPx gene expressions generally increased, whiles Mn-SOD and Zn/Cu-SOD reduced. Multivariate analysis showed that exposure to individual metals greatly influenced modulation of innate immune genes; whiles metal mixtures influenced antioxidant gene expressions. This suggests that beside oxidative stress, there may be other pathways influencing gene expressions of innate immune and antioxidant-related genes. Low concentration heavy metals also affect expression of development-related (wnt8a and vegf) genes. Altogether, the results of this study clearly demonstrate that low concentration individual and mixtures of metals in aquatic systems will greatly influence the immune system. It is indicative that mechanisms associated with

  16. A multivariate assessment of innate immune-related gene expressions due to exposure to low concentration individual and mixtures of four kinds of heavy metals on zebrafish (Danio rerio) embryos.

    Science.gov (United States)

    Cobbina, Samuel Jerry; Xu, Hai; Zhao, Ting; Mao, Guanghua; Zhou, Zhaoxiang; Wu, Xueshan; Liu, Hongyang; Zou, Yanmin; Wu, Xiangyang; Yang, Liuqing

    2015-12-01

    Concerns over the potential health effects of mixtures of low concentration heavy metals on living organisms keep growing by the day. However, the toxicity of low concentration metal mixtures on the immune system of fish species has rarely been investigated. In this study, the zebrafish model was employed to investigate the effect on innate immune and antioxidant-related gene expressions, on exposure to environmentally relevant concentrations of individual and mixtures of Pb (0.01 mg/L), Hg (0.001 mg/L), As (0.01 mg/L) and Cd (0.005 mg/L). Messenger-RNA (mRNA) levels of IL1β, TNF-α, IFNγ, Mx, Lyz, C3B and CXCL-Clc which are closely associated with the innate immune system were affected after exposing zebrafish embryos to metals for 120 h post fertilization (hpf). Individual and mixtures of metals exhibited different potentials to modulate innate-immune gene transcription. IL1β genes were significantly up regulated on exposure to Pb + As (2.01-fold) and inhibited on exposure to Pb + Hg + Cd (0.13-fold). TNF-α was significantly inhibited on exposure to As (0.40-fold) and Pb + As (0.32-fold) compared to control. Metal mixtures generally up regulated IFNγ compared to individual metals. Additionally, antioxidant genes were affected, as CAT and GPx gene expressions generally increased, whiles Mn-SOD and Zn/Cu-SOD reduced. Multivariate analysis showed that exposure to individual metals greatly influenced modulation of innate immune genes; whiles metal mixtures influenced antioxidant gene expressions. This suggests that beside oxidative stress, there may be other pathways influencing gene expressions of innate immune and antioxidant-related genes. Low concentration heavy metals also affect expression of development-related (wnt8a and vegf) genes. Altogether, the results of this study clearly demonstrate that low concentration individual and mixtures of metals in aquatic systems will greatly influence the immune system. It is indicative that mechanisms associated with

  17. 双酚A和壬基酚长期暴露对斑马鱼繁殖的影响%Effects of long term exposure to bisphenol A and nonylphenol on the reproduction of zebrafish (Danio rerio)

    Institute of Scientific and Technical Information of China (English)

    沈万赟; 周忠良; 李祥军

    2007-01-01

    内分泌干扰物的研究目前正逐渐成为国际研究新的热点,但长期暴露条件下对生殖情况的研究目前较少.本文研究了环境类雌激素双酚A(BPA)以及和壬基酚(NP)联合的作用,对暴露一个世代的斑马鱼(F1)(Danio rerio)的生殖情况、子代质量的影响.将健康的受精卵48 h后暴露于200,500,1 000 μg·L-1 BPA以及三个浓度与30 μg·L-1 NP的联合,同时设置空白对照和30 μg·L-1 NP对照.130 dph将成鱼置于清水喂养20 d,统计每天的产卵量、产卵次数、畸形率、孵化率、卵径、破膜时间以及耐饥时间.以此为终点评估暴露后斑马鱼的生殖能力和子代质量.与对照相比NP,BPA可以抑制斑马鱼的生殖,两种类雌激素联合作用可以极显著地抑制斑马鱼的生殖(P<0.01);BPA各浓度组导致F1代畸形率上升(P<0.05);高浓度BPA抑制产卵量(P<0.05);BPA200,500 μg·L-1会延长F1代的破膜时间和耐饥时间(P<0.01),而BPA1 000 μg·L-1则产生相反的效果(P<0.05).双酚A对斑马鱼的生殖有明显的抑制作用,双酚A和壬基酚有协同效应.长时间暴露于双酚A会影响斑马鱼的生殖能力和子代质量.

  18. 睾酮与TBTC抑制斑马鱼卵巢发育的分子机制%Mechanisms Involved in the Inhibition of Zebrafish (Danio rerio) Ovarian Development by Testosterone and Tributyltin Chloride

    Institute of Scientific and Technical Information of China (English)

    饶剑军; 李英文; 张群芳; 刘智皓

    2016-01-01

    为探讨雄激素与三丁基锡对鱼类卵巢发育和配子发生的影响及其分子差异,分别用1 μg·L-1睾酮(T)、1μg·L-1三丁基氯化锡(TBTC)单独处理以及T、TBTC(两者含量均为1 μg·L-1)联合处理对斑马鱼(Danio rerio)雌鱼进行了90 d暴露.组织学结果表明:与对照相比,经T、TBTC单独处理的斑马鱼成熟系数(GSI)下降,卵巢发育受阻,卵子发生抑制,且TBTC单独处理的斑马鱼发育后期的卵母细胞大量凋亡;经T、TBTC联合处理的斑马鱼卵母细胞尽管在发育后期发生凋亡,但仍有少量卵母细胞持续发育,GSI值明显升高.定量PCR结果表明:T和TBTC单独处理都能显著下调雌激素(E2)合成酶基因cyp19a及其上游调控基因foxl2的表达(p<0.05),而两者联合处理则显著上调cyp19a和foxl2基因表达(p<0.05);T单独处理的斑马鱼雄激素合成酶基因P450 11β的表达显著升高(p<0.05),而TBTC单独处理使该基因表达显著下降(p<0.05),T、TBTC联合处理对该基因表达无显著影响;T、TBTC单独处理均不影响孕激素合成酶基因20β HSD的表达,但T、TBTC联合处理却显著上调该基因的表达(p<0.05).研究认为T、TBTC抑制斑马鱼卵巢发育和卵子发生的机制可能既相似又有所差异.

  19. Exposure to perchlorate induces the formation of macrophage aggregates in the trunk kidney of zebrafish and mosquitofish

    Science.gov (United States)

    Capps, T.; Mukhi, S.; Rinchard, J.J.; Theodorakis, C.W.; Blazer, V.S.; Patino, R.

    2004-01-01

    Environmental contamination of ground and surface waters by perchlorate, derived from ammonium perchlorate (AP) and other perchlorate salts, is of increasing concern. Exposure to perchlorate can impair the thyroid endocrine system, which is thought to modulate renal and immune function in vertebrates. This study with zebrafish Danio rerio and eastern mosquitofish Gambusia holbrooki examined the histological effects of perchlorate on the trunk kidney, which in teleosts serves excretory and hemopoietic functions and therefore may be a target of perchlorate effects. Adult zebrafish of both sexes were exposed in the laboratory to waterborne, AP-derived perchlorate at measured concentrations of 18 mg/L for 8 weeks. Adult male mosquitofish were exposed to waterborne sodium perchlorate at measured perc