Letteratura scientifica selezionata sul tema "Danio rerio – Larves"

O objetivo deste trabalho foi testar o efeito tóxico de diferentes concentrações de extrato hidroalcoólico da planta Baccharis dracunculifolia, utilizando larvas de zebrafish (Danio rerio) de 8 dias pós-fertilização. No primeiro ensaio 50,0, 25,0, 12,5, 6,25, 3,125, 1,563 e 0,781 mg/mL de extrato foram diluídos em H2O e foram realizadas observações em 0, 1 e 2 horas das larvas expostas ao extrato. No segundo ensaio, as diluições foram 2,0; 1,0; 0,40 e 0,20 mg/mL do extrato em H2O e exposição das larvas no extrato em 0, 4, 8 e 12 horas. A partir do desenvolvimento dos dois testes pode-se verificar que quando as larvas foram expostas a extratos de B. dracunculifolia com diluições superiores a 2,0 mg/mL, obteve-se 100% de mortalidade assim que a larva foi exposta. A exposição de larvas de zebrafish (Danio rerio) aos oito dias após-fertilização nos diferentes níveis de diluição do extrato hidro alcoólico de B. dracunculifolia apresentou efeitos letais. Porém, quando foram testadas diluições a partir de 0,40 mg/mL, obteve-se um baixo percentual de mortalidade.

Objetivo: Avaliar os efeitos tóxicos causados ​​pela exposição a antidiabéticos em concentrações encontradas no meio ambiente sob os parâmetros biológicos de Danio rerio. Métodos: O desenvolvimento embrionário e larval foi avaliado sob exposição à metformina, glibenclamida, glimepirida e gliclazida de 1 a 144 hpf. Os possíveis efeitos tóxicos foram divididos em letais, subletais e teratogênicos. Resultados: Todos os antidiabéticos causaram uma mortalidade baixa de menos de 10% causada pela ausência de batimento cardíaco. O efeito subletal em animais expostos à metformina foi a ausência de inflação da bexiga natatória nas larvas. A glibenclamida apresentou efeitos subletais e teratogênicos em todas as concentrações, sendo considerada a droga mais tóxica. A glimepirida causou uma redução na pigmentação e a gliclazida teve a toxicidade mais baixa, mas foi a única droga que causou retardo de crescimento. Conclusão: Concluímos que os fármacos avaliados apresentam baixa toxicidade. Encontramos toxicidade diferente nas duas fases do desenvolvimento do peixe-zebra, sendo as larvas as mais afetadas. Como a metformina é o antidiabético mais comum encontrado no ambiente aquático, recomendamos o monitoramento desse composto para tentar mitigar possíveis impactos ambientais.

Los aceites esenciales y extractos de plantas,cultivadas de forma orgánica en la finca El Limonal Piedecuesta-Santander, Colombia, obtenidos por hidrodestilación asistida por microondas y percolación, se caracterizaron por cromatografía de gases acoplada a espectrometría de masas. La actividad insecticida se evaluó frente a larvas en tercer instar de Culex quinquefasciatus y en la enzima acetilcolinesterasa. La toxicidad se determinó en el modelo del pez cebra (Danio rerio). De ellos, el aceite esencial de Ruta graveolens fue el que presentó la mejor actividad larvicida, con CL50 7.20±0.19 μg/mL, una moderada inhibición de la enzima con IC50 44.98±1.1 μg/mL y moderada toxicidad con CL50 13.33±0.59 mg/L.

En la actualidad, una amplia gama de contaminantes son detectados en el ambiente con implicaciones en la salud y en la biodiversidad, su elevado número ha dificultado su estudio con métodos de experimentación in vitro e in vivo. Se implementó en el modelo del pez cebra un sistema de bajo costo para evaluar el efecto de los contaminantes ambientales, utilizando la actividad motora como marcador de neurotoxicidad. Embriones fueron expuestos a concentraciones de 0.05, 0.5, 5, 50 mg/l de arsénico inorgánico (Asi), 0.03, 0.3, 3, 10 mg/l de atrazina (ATR) y 14.5, 29.1, 43.6 mg/l de tiametoxam (TMX). La actividad motora aumentó en larvas expuestas a ATR y Asi y disminuyó con dosis altas de TMX. Estos datos sugieren que el sistema implementado es sensible para detectar cambios en la conducta motora en larvas del pez cebra, lo que puede contribuir positivamente al estudio de los contaminantes ambientales.

No presente estudo, avaliamos os efeitos tóxicos das drogas antiepilépticas gabapentina (GAB), fenobarbital (PB), oxcarbazepina (OX) e lamotrigina (LTG), os efeitos letais, subletais, teratogênicos e parâmetros morfométricos em embriões e larvas de peixe-zebra (Danio ri). Um teste de toxicidade aguda foi realizado usando embriões de D. rerio de acordo com as diretrizes OECD 236 (2013). O teste de toxicidade aguda revelou que a mortalidade de animais aumentou com o passar do tempo (24 a 96 hpf) em animais expostos a GAB, PB, OX e LTG. Os efeitos subletais tiveram uma variação significativa (p <0,05) no número de batimentos cardíacos, não de forma dependente da dose. Também foi possível observar variação na pigmentação em todos os animais e a presença de edema pericárdico em alguns grupos. Os efeitos teratogênicos revelaram malformação da cabeça apenas nos animais expostos ao GAB. Além disso, deformação da cauda, ​​deformação da coluna, edema do saco vitelino e bexiga natatória inflada foram observados em todos os animais. Os parâmetros morfométricos tiveram uma diminuição (p <0,05) no comprimento corporal, largura da cabeça, distância ocular, distância entre os olhos e diâmetro do olho em todos os grupos no 96 hpf. Foi observado que gabapentina, fenobarbital, oxcarbazepina e lamotrigina induzem efeitos letais, subletais, teratogênicos e alterações morfométricas no peixe-zebra.

Nosso estudo buscou avaliar o impacto do enriquecimento ambiental sobre repostas comportamentais no zebrafish. Para isso, larvas com 5 dias pós-fertilização (dpf) foram divididas em dois grupos: (1)controle - aquário padrão; (2)experimenral - ambiente enriquecido com diferentes apetrechos (plantas, cascalhos, enfeites coloridos, tronco e concha artificiais). Ao completarem 60dpf, os animais foram submetidos a testes comportamentais (Tanque Novo e Claro/Escuro) e, posteriormente, induzidos à crise epiléptica. Nossos resultados indicaram que os animais mantidos em ambiente enriquecido não apresentaram diferenças significativas para a maioria dos parâmetros analisados e exploraram menos o ambiente mais aversivo do teste do Claro-Escuro. Curiosamente, os animais experimentais apresentaram menor comprimento crâniocaudal em relação ao grupo controle.

Introduction/rationale: Current anti-diabetic drug treatments have a variety of adverse side effects. Identifying functional foods with anti-diabetic properties may be the key to preventing and managing T2DM while minimizing side effects. Studies found that Pck-1 gene is often down-regulated by anti-diabetic drugs, as its enzyme is responsible for catalyzing the rate-limiting step of gluconeogenesis. In our study, we screened for functional foods that can down-regulate the expression of the Pck-1 gene. The newly emerged zebrafish (Danio rerio) is aptly suited for in vivo nutrigenomic screening due to its large clutch size and conservation of molecular pathways with humans, including those involved in glucose regulation. Methods: We exposed zebrafish larve (Tg(Pck-1:luc), a luminescent reporter line for Pck-1), at 4 days post fertilization (dpf) to extracts from forty functional fruits and vegetables. The level of Pck-1 expression was quantified by luminescence at 6 dpf. Extracts which resulted in a lower reading of luminescence were interpreted as functional foods that could successfully down-regulate Pck-1 expression, and therefore may be potential therapeutic for T2DM. We further validated our results using a fluorescent reporter line for Pck-1 (Pck-1:eGFP). Results: We completed toxicity assays on the functional food extracts to determine the optimal concentrations and conditions for nutrigenomic screening. Preliminary results show that bamboo and cherry extracts significantly reduced Pck-1 gene expression by two fold (p<0.05). Other functional food extracts, such as grape, cucumber, cabbage, spinach, flat beans, and lemon also reduced Pck-1 gene expression. Interestingly, garlic extracts increased Pck-1 gene expression. Conclusion and Discussion: We identified two functional food extracts that successfully reduced Pck-1 expression in zebrafish models. Increasing the intake of these two functional foods may regulate blood glucose levels in T2DM patients. Further research elucidating the active ingredient in these foods is required. The Pck-1 zebrafish model can be employed for further nutrigenomic screening and/or for drug discovery purposes.

Les esters de phtalate constituent une famille de composés synthétiques très répandue du fait de leurs usages comme plastifiants. Ils entrent dans la composition de plusieurs produits plastiques tels que les emballages, les jouets, les produits cosmétiques, certains systèmes de toiture en plastique, ainsi que les matériaux de décoration de meubles. Les phtalates ne sont pas liés de manière covalente à la matrice des polymères et sont donc facilement rejetés dans l'environnement, entraînant par conséquent une exposition animale et humaine. En absence de produits de substitutions non-toxiques, les composés de type phtalate restent encore largement utilisés dans l'industrie en dépit de la classification de certains d'entre eux dans la catégorie des substances présumées toxiques par l'European Chemicals Agency (ECHA), en tant que perturbateurs endocriniens. De plus, ils sont cancérigènes et tératogènes. L'effet délétère des esters de phtalates sur les organismes est établi mais le caractère multiple des effets observés montre que les mécanismes d'action des phtalates ne sont que très partiellement élucidés. Nous avons utilisé deux approches de protéomique ciblée pour tenter d'éclairer nos connaissances sur les mécanismes d'actions des esters de phtalate. Pour cela, le dibutyl phtalate (DBP) a été utilisé comme phtalate modèle, et le poisson zèbre (D. rerio) comme organisme modèle. L'utilisation de la première approche de protéomique ciblée, le profilage protéique basé sur l'affinité (affinity-based protein profiling, AfBPP) a permis de montrer la perturbation fonctionnelle de protéines par le DBP avec des sondes photoactivables issues de la synthèse de types aryle azide. L'optimisation des conditions de fixation des sondes diazirine (Diazirine 2) devrait nous permettre de disposer d'une sonde pouvant être utilisée pour identifier les cibles protéiques du DBP dans le protéome du poisson zèbre. La deuxième approche, le profilage basé sur l'activité des enzymes (activity-based protein profiling, ABPP) a permis d'utiliser une sonde réactive spécifique des hydrolases à sérine (SHs) pour cartographier pour la première fois des SHs actives dans le protéome du poisson zèbre. L'identification des SHs dérégulées en présence de DBP chez les larves de poisson zèbre a également été rapportée dans cette étude. Nos résultats globaux indiquent que les approches de protéomiques ciblées telles que l'ABPP ou l'AfBPP peuvent être un atout pour comprendre les mécanismes d'action liés aux xénobiotiques en écotoxicologie
Phthalate esters are a family of synthetic compounds widely used as plasticisers. They are used in a number of plastic products such as packaging, toys, cosmetics, plastic roofing system and furniture decoration materials. Phthalates are not covalently bonded to the polymer matrix and are therefore easily released into the environment, resulting in animal and human exposure. In the absence of non-toxic substitutes, phthalate compounds are still widely used in industry, despite the classification of some of them by the European Chemicals Agency (ECHA) as suspected toxic substances and as endocrine disruptors. In addition, they are carcinogenic and teratogenic. The deleterious effect of phthalate esters on organisms is established, but the multiple nature of the effects observed shows that the mechanisms of action of phthalates are only partially elucidated. We used two targeted proteomics approaches to shed light on the mechanisms of action of phthalate esters. Dibutyl phthalate (DBP) was used as a model phthalate and zebrafish (D. rerio) as a model organism. Using the first targeted proteomics approach, affinity-based protein profiling (AfBPP), the functional disruption of proteins by DBP with photoaffinity probes from aryl azide synthesis was demonstrated. Optimisation of the binding conditions for diazirine probes (Diazirine 2) should provide us with a probe that can be used to identify DBP protein targets in the zebrafish proteome. The second approach, activity-based protein profiling (ABPP), used a reactive probe specific for serine hydrolases (SHs) to map active SHs in the zebrafish proteome for the first time. The identification of deregulated SHs in the presence of DBP in zebrafish larvae was also reported in this study. Overall, our results indicate that targeted proteomics approaches such as ABPP or AfBPP can be an asset for understanding xenobiotic-related mechanisms of action in ecotoxicology

Dans le but de comprendre les mécanismes relatifs à la mise en place des axes lors du développement embryonnaire précoce des lophotrochozoaires, les rôles morphogénétiques des récepteurs aux protéines de la superfamille des TGF- s ainsi que leurs implications en tant que cytokine ont été étudiés chez l'huître creuse C. Gigas. Après avoir cloné les transcrits et les gènes codant quatre de ces récepteurs (TGF- type I, activine type I et BMP types I et II) ainsi qu'une protéine de type BMP1/Tolloid, utilisant ensuite le poisson zèbre en tant " qu'organisme rapporteur ", la microinjection d'ARNm synthétisés in vitro dans ces embryons a démontré la capacité de ces molécules à jouer un rôle lors de l'embryogenèse précoce. Lors de la gastrulation, par interférence avec les molécules orthologues endogènes de poisson zèbre, la surexpression de ces transcrits résulte en la perturbation de la mise en place des axes dorsoventraux et antéropostérieurs via la modulation de l'induction du mésoderme.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
The low-power LASER is a technology used in the area of ​​health as adjuvant therapy for various diseases. The use of conservative therapies as adjuncts to drug therapy, aim to potentiate therapeutic responses. There are currently some contraindications for the use of LASER in treatments of human patients with open wounds, tumor region and gravid uterus. Thus, zebrafish (D. rerio) is a consolidated organism as an experimental model in the biological, biomedical and environmental areas. The objective of the present work is to evaluate the development of embryos and larvae of zebrafish (D. rerio) exposed to low-power LASER. The LASER III flash with transverse beam output 0,028 cm2, power 100 mW, creep 35, 70 and 140 J / cm2, total energy of 1, 2 and 4 J (Joules), InGaAlP active medium, was used. The data were evaluated according to the normality behavior of Lilliefors using Fisher's exact test, t-test, Mann-Whitney, Kruskal-Wallis (post hoc-Dunn) and Linear Regression by the ORIGIN 7.0 program. The cumulative mortality rate and hatching in embryos (D. rerio) exposed to the LASER in the red spectrum 660 nm and infrared 830 nm 1, 2 and 4 J from 24 - 24 h to 96 hpf was not statistically significant in relation to the wavelength in energy doses in Joules (p ˃ 0,05), infrared laser 830 nm 4J, did not interfere in the development of embryos and larvae (D. rerio), when exposed from 24 - 24 h for a period of 216 hpf. The cumulative mortality rate in the control group was 23 % higher than in the LASER group and the hatching rate in the LASER group was statistically significant (p ˂ 0,05). The cumulative mortality rate in embryos and larvae (D. rerio) when exposed intensively to LASER was statistically significant, as was the hatching rate (p ˂ 0,05) for 96 hpf. There were no statistically significant differences for larval length between the control group compared to the LASER group 24 - 24 h and intensive LASER (p ˃ 0,05). The rate of heart rate in the LASER group 24 - 24 h was statistically significant in relation to the control group and the intensive LASER group (p ˂ 0,05). The rate of spontaneous movements was statistically significant when compared to the control group and the intensive LASER group (p ˂ 0,05). The rate of edema in the control group was statistically significant in relation to the LASER group 24 - 24 h for 96 hpf (p ˂ 0,05). The rate of edema in the intensive LASER group was not statistically significant; however, as in the LASER group 24 - 24 h, the edema in the control group was higher than in the LASER group. The scarcity of theoretical reference on this theme reinforces the pioneering of this work carried out in vivo. The results of this study highlight the importance of the use of embryos and larvae (D. rerio) as a model system in biological, environmental and biomedical research. Data analysis suggests that contraindications for low-power LASER irradiation in patients during the gestational period should be reviewed.
O LASER de baixa potência é uma tecnologia utilizada na área da saúde como terapia coadjuvante a diversas doenças. A utilização de terapias conservadoras como coadjuvantes a terapia medicamentosa, visam potencializar as repostas terapêuticas. Atualmente há algumas contraindicações para utilização do LASER em tratamentos de pacientes humanos com feridas abertas, região tumoral e útero gravídico. Sendo assim, o zebrafish é um organismo consolidado como modelo experimental nas áreas biológica, biomédica e ambiental. O objetivo do presente trabalho é avaliar o desenvolvimento de embriões e larvas do zebrafish (D. rerio) expostos ao LASER de baixa potência. Utilizou-se o flash LASERIII com saída transversa do feixe 0,028 cm2, potência 100 mW, fluência 35, 70 e 140 J/cm2, energia total de 1, 2 e 4 J(Joules), meio ativo InGaAlP. Os dados foram avaliados segundo o comportamento de normalidade Lilliefors através dos testes Exato de Fisher, teste t, Mann-Whitney, Kruskal-Wallis (post hoc-Dunn) e Regressão Linear pelo programa ORIGIN 7.0. A taxa de mortalidade acumulativa e eclosão em embriões (D. rerio) expostos ao LASER no espectro vermelho 660 nm e infravermelho 830 nm 1, 2 e 4 J de 24 - 24 h para 96 hpf não foi estatisticamente significativas em relação ao comprimento de onda em doses de energia em Joules (p ˃ 0,05), O LASER infravermelho 830 nm 4J, não interferiu no desenvolvimento de embriões e larvas (D. rerio), quando expostos de 24 - 24 h por um período de 216 hpf. A taxa de mortalidade acumulativa no grupo controle foi 23 % maior que no grupo LASER e a taxa de eclosão no grupo LASER foi estatisticamente significativa (p ˂ 0,05). A taxa de mortalidade acumulativa em embriões e larvas (D. rerio) quando expostos de forma intensiva ao LASER, foi estatisticamente significativa, assim como a taxa de eclosão (p ˂ 0,05) para 96 hpf. Não houve diferenças estatisticamente significativas para comprimento larval entre o grupo controle em relação ao grupo LASER 24 - 24 h e LASER intensivo (p ˃ 0,05). A taxa de batimentos cardíacos no grupo LASER 24 - 24 h foi estatisticamente significativo em relação ao grupo controle e ao grupo LASER intensivo (p ˂ 0,05). A taxa de movimentos espontâneos foi estatisticamente significativa, quando comparada ao grupo controle e ao grupo LASER intensivo (p ˂ 0,05). A taxa de edema no grupo controle foi estatisticamente significativa em relação ao grupo LASER 24 - 24 h para 96 hpf (p ˂ 0,05). A taxa de edema no grupo LASER intensivo não foi estatisticamente significativa, no entanto, assim como no grupo LASER 24 - 24 h, o edema no grupo controle foi maior que no grupo LASER. A escassez de referencial teórico sobre essa temática reforça o pioneirismo desse trabalho realizado in vivo. Os resultados desse estudo ressaltam a importância da utilização de embriões e larvas (D. rerio) como Sistema - modelo em pesquisas biológicas, ambientais e biomédicas. As análises dos dados sugerem que as contraindicações para irradiação com o LASER de baixa potência em pacientes durante o período gestacional sejam revistas.

As doenças inflamatórias intestinais são caracterizadas por uma desregulação na resposta imune contra a microbiota. O zebrafish, tem emergido como um novo modelo para o estudo de doenças inflamatórias. Os ácidos graxos de cadeia curta (AGCCs) são produtos da microbiota intestinal, que possuem papéis antiinflamatórios e aparecem como uma das possíveis terapias contra doenças inflamatórias. A implementação do modelo de inflamação intestinal induzido pelo ácido trinitrobenzenesulfônico (TNBS) em larvas de zebrafish aumentou a mortalidade de forma dose-dependente. Se observou dilatação do lúmen com alisamento das vilosidades intestinais. Não se detectaram mudanças na produção de muco nem no número de células caliciformes mas teve um leve aumento da apoptóse e diminuição da proliferação, nos expostos ao TNBS. Teve aumento de células mielóides infiltrantes e de citocinas inflamatórias, assim como disbiose da microbiota. O tratamento com AGCCs gero alta mortalidade a concentrações acima de 10 mM, mas existe ação anti-inflamatória a esta mesma concentração.
Inflammatory bowel diseases are characterized by a dysregulation in immune response against microbiota. The zebrafish has emerged as a new model for the study of inflammatory diseases. Short chain fatty acids (SCFAs) are products of the intestinal microflora, which have anti-inflammatory roles and appear as a possible therapy against inflammatory diseases. The implementation of intestinal inflammation model induced by trinitrobencenesulfonic acid (TNBS) in zebrafish larvae, increased mortality in a dose-dependent manner. Was observe dilatation lumen and straightening of the intestinal villi. No changes were detected in the production of mucus or in the number of goblet cells but had a slight increase in apoptosis and decreased proliferation in exposed to TNBS. Also has, increased cytokines and infiltrating myeloid cells, and dysbiosis of the microbiota. Treatment with SCFAs generate high mortality above 10 mM concentrations, but there anti-inflammatory action to this same concentration.

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Recent studies have shown several applications of graphene oxide (GO) in neurology in the imaging area as a contrast agent for diagnostic purposes, for drug delivery of anticarcinogenic drugs, proteins and peptides and in the field of tissue engineering for applications in the regeneration of nervous lesions. Advances in GO applications research in neurology require addressing its potential toxic mechanisms of action. Zebrafish (Danio rerio) has been widely used in neurotoxicological trials due to the homology of biochemical processes and neural structures with vertebrates. To investigate the potential neurotoxic effects of GO exposure in different concentrations at development period, we evaluated in vivo parameters for initial toxicological screening. We found that GO did not induce changes in survival, hatching and spontaneous movement. However, an increase in heart rate at 48 hpf was found and a reduction in body length without altering the ocular area at 5 dpf. Additionally, molecular gene expression analyses of nervous system-related proteins were performed, showing synapsin IIa expression is increased and dopamine transporter (dat) gene expression is reduced, suggesting a potential compensatory mechanism. The evaluation of the locomotion behavior of animals exposed at GO showed an increase in the absolute turn angle. Based on these initial parameters, we performed biochemical analyzes to determination of the enzyme acetylcholinesterase (AChE) activity and dopamine levels. The exposure at GO did not change AChE activity and decreased dopamine levels. Additionally, the gene expression of B cell lymphoma 2 (bcl2) gene and caspase 3 (casp3) gene were evaluated for the group of larvae exposed to GO, demonstrating an increase of bcl2 and unchanged casp3 expression, suggesting no apoptosis involvement. The tissue and cellular structure of zebrafish larvae brain exposed at GO was evaluated by transmission electron microscopy (TEM) and cell dead by autophagosome formation with loss of cellular architecture was observed most likely due to exposure to the nanomaterial. Further studies are necessary to the complete understanding of the neurological changes observed in zebrafish by exposure to GO and the mechanisms involved in this process, are necessary.
Estudos recentes t?m mostrado diversas aplica??es do ?xido de grafeno (GO) como agente de contraste para fins de diagn?stico, para o endere?amento de drogas (do ingl?s drug delivery) de f?rmacos anticarcinog?nicos, prote?nas e pept?deos e na ?rea de engenharia tecidual para aplica??es na regenera??o de les?es nervosas. O avan?o em pesquisas relacionadas a aplica??es do GO em neurologia exige a investiga??o dos mecanismos de a??o potencialmente t?xicos desencadeados pela exposi??o ao nanomaterial. O zebrafish (Danio rerio) tem sido amplamente utilizado em ensaios neurotoxicol?gicos devido ? homologia de processos bioqu?micos e estruturas neurais com outros vertebrados, vis?veis desde o in?cio de seu desenvolvimento externo. Para investigar os efeitos neurot?xicos da exposi??o a diferentes concentra??es do GO no per?odo de desenvolvimento, foram avaliados diversos par?metros in vivo para avalia??o toxicol?gica preliminar. Foi verificado que o GO n?o induziu altera??es na sobreviv?ncia, eclos?o e movimentos espont?neos. Contudo, o aumento dos batimentos card?acos em 48 hpf foi constatado e redu??o do tamanho do eixo axial, sem altera??o na ?rea ocular em 5 dpf. Adicionalmente, an?lises moleculares da express?o de genes espec?ficos para prote?nas do sistema nervoso foram realizadas mostrando que o GO aumenta a express?o de sinapsina IIa e reduz a express?o do transportador de dopamina (dat), sugerindo um prov?vel mecanismo compensat?rio. A avalia??o da locomo??o dos animais expostos ao GO mostra o aumento do ?ngulo absoluto de virada. Com base nestes par?metros iniciais, foram realizadas an?lises bioqu?micas para a determina??o da atividade da enzima acetilcolinesterase (AChE) e dosagem dos n?veis de dopamina. A exposi??o ao GO n?o alterou a atividade da AChE e reduziu os n?veis de dopamina. Adicionalmente, a express?o do gene de linfoma de c?lulas B2 (do ingl?s B cell lymphoma 2 (bcl2) ) e do gene que codifica para caspase 3 (casp3) foram avaliadas para o grupo de larvas expostas ao GO onde foi mostrado aumento da express?o de bcl2, enquanto que a express?o de casp3 permaneceu inalterada, sugerindo que o GO parece n?o induzir mecanismo de apoptose. A estrutura tecidual e celular do c?rebro de larvas de zebrafish expostas ao GO foi avaliada por microscopia eletr?nica de transmiss?o (TEM) onde morte celular por necrose com perda da arquitetura celular foi constatada. Estudos adicionais para o completo entendimento das altera??es neurol?gicas observadas pela exposi??o ao GO e dos mecanismos envolvidos nesse processo s?o necess?rios.

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CAPES
A WSMoL (do inglês water-soluble Moringa oleifera lectin) é uma lectina (proteína que reconhece carboidratos) proveniente das sementes da Moringa oleifera, as quais são utilizadas no tratamento de água. Algumas espécies de insetos podem atuar como vetores de doenças ou pragas agrícolas. O mosquito Aedes aegypti é o vetor da dengue e sabe-se que o extrato de sementes de M. oleifera e WSMoL são tóxicos para as larvas deste inseto. O extrato de sementes e WSMoL apresentaram uma concentração letal a 50% das larvas após 24 horas de exposição (CL₅₀) igual a 0,27 mg/mL e 0,197 mg/mL, respectivamente. Entretanto, para uma adequada utilização desse inseticida natural se faz necessário a realização de testes ecotoxicológicos a fim de avaliar os possíveis efeitos causados em organismos aquáticos não-alvo. Neste trabalho, foi avaliada a toxicidade de extrato de semente e WSMoL para larvas de Danio rerio, espécie de peixe muito utilizada na Ecotoxicologia devido à facilidade de observação de seu comportamento e desenvolvimento e serem sensíveis na fase larval. As larvas de D. rerio foram expostas a diferentes concentrações do extrato de sementes ou WSMoL por 168 horas (7 dias),tendo sido avaliados efeitos letais por meio da determinação da taxa de mortalidade. Além disso, efeitos sub-letais comportamentais e bioquímicos sobre a velocidade natatória das larvas e atividade da acetilcolinesterase, respectivamente,também foram avaliados. Foi observado um efeito dose dependente na taxa de mortalidade de D. rerio tanto para o extrato quanto para a lectina purificada. Após 24 horas, os valores de CL₅₀/₂₄h foram 0,365 e 0,21 mg/mL para extrato e WSMoL, respectivamente. Esses resultados mostram que a susceptibilidade das larvas de D. rerio a WSMoL foi similar a das larvas de A. aegypti (6% de diferença nos valores de LC₅₀/₂₄h) enquanto extrato é aproximadamente 34% mais potente para as larvas do mosquito. Após 96 horas, os valores de CL₅₀/₂₄h para extrato e WSMoL foram 0,031 e 0,135 mg/mL, respectivamente. Com relação à velocidade natatória dos indivíduos expostos ao extrato, houve um aumento significativo (p < 0,05) após incubação nas concentrações 0,03 e 0,27 mg/mL e uma diminuição para larvas incubadas com 0,81 mg/mL por esse mesmo período. Para incubação por 168 h, a velocidade foi maior que no grupo controle para os tratamentos a 0,27 e 0,81 mg/mL. Nos ensaios com WSMoL, a média da velocidade de natação de larvas expostas à lectina por 72 h foi significativamente (p < 0,05) menor que no controle nos tratamentos com 0,1 e 0,2 mg/mL. Para 168 h, a velocidade foi também menor que no controle no tratamento a 0,1 mg/mL enquanto para as concentrações de 0,02 e 0,05 mg/mL foi similar (p > 0,05) ao controle.Larvas expostas por 168 h ao extrato aquoso na concentração 0,81 mg/mL e a WSMoL na concentração de 0,1 mg/mL apresentaram uma redução significativa na atividade da acetilcolinesterase. Levando em consideração os resultados obtidos, esses inseticidas naturais devem ser usados cuidadosamente, uma vez que as concentrações necessárias para o controle de A. aegyptiforam podem também causar efeitos tóxicos letais e sub-letais para organismos não-alvo como o peixe D. rerio. Recomenda-se o uso em recipientes de armazenamento de água, e não em ecossistemas aquáticos como lagoas e lagos.
Some insect species can act as vectors of diseases or as agricultural pests. The WSMoL (water soluble Moringa oleifera lectin) is a lectin (protein that recognizes carbohydrate) derived from the seeds of Moringa oleifera, which are used in water treatment. The mosquito Aedes aegypti is the vector of dengue and it is known that M. oleifera seed extract and WSMoL are toxic to larvae of this insect. The seed extract and WSMoL showed a lethal concentration to 50% of the larvae after 24 hours of exposure (LC₅₀) equal to 0.27 mg/mL and 0.197 mg/mL, respectively. However, for proper use of these natural insecticides, it is necessary to carry out ecotoxicological tests in order to assess the possible effects on non-target aquatic organisms. In this work, the toxicity of seed extract and WSMoL to zebrafish (Danio rerio) larvae was evaluated. Danio rerio is a fish species very used in Ecotoxicology due to the ease of observation of its behavior and development and for being sensitive in the larval stage. D. rerio larvae were exposed to different concentrations of the seed extract or WSMoL for 168 h (7 days) and the lethal effects were assessed by determining the mortality rate. Additionally, behavioral and biochemical sublethal effects on larval swimming velocity and acetylcholinesterase activity, respectively, were also evaluated. It was observed a dose dependence effect on D. rerio mortality rate for both the extract and the purified lectin. After 24 h, the values of LC₅₀/₂₄h were 0.365 and 0.21 mg/mL to extract and WSMoL, respectively. These results show that the D. rerio larvae susceptibility to the WSMoL was similar to A. aegypti larvae (6% difference in LC₅₀/₂₄h values) while extract was about 34% more potent against mosquito larvae. After 96 h, the values of LC₅₀/₂₄h for extract and WSMoL were 0.031 and 0.135 mg/mL, respectively. Concerning the swimming velocity of individuals exposed to the extract there was a significant increase (p <0.05) after incubation for 72 h at 0.03 and 0.27 mg/mL and a decrease for larvae incubated at 0.81 mg/mL for this same period. For 168 h incubation, the velocity was higher than control group for treatments at 0.27 and 0.81 mg/mL. In tests with WSMoL, the average swimming velocity of larvae exposed to the lectin for 72 h was significantly (p <0.05) lower than the control on treatments with 0.1 and 0.2 mg/mL. For 168 h, the velocity was also lower than the control on treatment with 0.1 mg/mL, and with concentrations of 0.02 and 0.05 mg/mL the values were similar (p>0.05) to the control. Larvae exposed for 168 h to the aqueous extract at a concentration of 0.81 mg/mL and WSMoL at 0.1 mg/mL showed a significant reduction in the activity of acetylcholinesterase. Considering the results, these natural insecticides must be used carefully used since the concentrations necessary for the control of A. aegypti also can cause lethal toxic effects and sub-lethal to non-target organisms such as D. rerio fish. It is not recommended to use these natural insecticides in aquatic ecosystems such as ponds and lakes, but in water storage containers.

Superior swimming stamina in adult fish is presumably passed on to their offspring, but the ontogeny of the appearance of superior stamina and the requisite enhanced cardio-respiratory support for locomotion in larval fishes has not been determined. Is the expression of the suite of parental traits enabling superior swimming stamina in their offspring dependent upon their achieving juvenile/adult morphology, or does it appear earlier in their larvae? To answer this, adults were classified into three groups based on swimming stamina, followed by measurement of length, mass, and width. Larval offspring from the two parental groups -high stamina larvae (HSL) and low stamina larvae (LSL)- were reared at 27°C in aerated water (21% O2). Routine and active heart rate, routine and active mass specific oxygen consumption were recorded through 21dpf, and cost of transport (COT) and factorial aerobic scope were derived from oxygen consumption measurements. Routine heart rate at 2dpf of LSL was 164 ± 1 b·min-1, compared to only 125 ± 2 b·min-1 for HSL. Routine heart rate subsequently peaked at 203 ± 1 b·min-1 at 5dpf in the HSL group, compared to 207 ± 1 b·min-1, at 4dpf in the LSP larvae. Active heart rate at 5 dpf of LSL was 218 ± 2 b·min-1 compared to 216 ± 2 b·min-1 for HSL. Active heart rate increased slightly to 227 ± 2 b·min-1 for LSL before decreasing again, while active heart rate remained relatively constant for HSL. Routine O2 consumption at 2dpf of HSL was 0.09 μmol·mg-1·hr-1, compared to 0.03 μmol·mg-1·hr-1 in LSL. Routine O2 consumption subsequently peaked at 0.70 μmol·mg-1·hr-1 at 9dpf in the HSL, compared to 0.71 μmol·mg-1·hr-1, at 9dpf in the LSL. These values dramatically decreased before leveling off at around 0.20 μmol·mg-1·hr-1 and 0.15 μmol·mg-1·h-1, respectively. Active O2 consumption at 5dpf for HSL was 0.38 μmol·mg-1·hr-1, compared to 0.57 μmol·mg-1·hr-1 for LSL. Active O2 consumption subsequently peaked at 0.97 μmol·mg-1·hr-1 at 10dpf in HSL, compared to 1.19 μmol·mg-1·hr-1 at 7dpf in LSL. These values also dramatically decreased and leveled off. Significant differences (p < 0.05) in heart rate and oxygen consumption persisted through 21dpf. The onset of differences observed in routine and active heart rate in early larvae, correlated with parent stamina, show that juvenile or adult features are not required as a precondition for the emergence of phenotypic physiological differences.

Mestrado em Biologia Molecular e Celular
The scientific community has been concerned for several years about the presence of pharmaceuticals in the wild, since these compounds may have deleterious or unpredictable effects on living organisms. The scientific knowledge on the fate and effect of drug residues in the environment has evolved considerably in recent years, revealing that drug residues do indeed pose a threat to the aquatic ecosystem. Two examples of widely used pharmaceuticals that are present in the environment are paracetamol (acetaminophen) and ciprofloxacin, Paracetamol is a drug with analgesic properties, used for the temporary relief of mild to moderate pain associated with common colds, and in the reduction of fever. Ciprofloxacin is an antibiotic from the chemical class of the fluoroquinolones which presents a broad antibacterial spectrum. Firstly we decided the range of concentrations for each drug. In the case of paracetamol, the tested concentrations were 0.005 mg/L, 0.025 mg/L, 0.125 mg/L, 0.625 mg/L, and 3.125 mg/L, plus a control treatment with water from the facility system. And for ciprofloxacin, the tested concentrations were 0.005 μg/L, 0.013 μg/L, 0.031 μg/L, 0.078 μg/L, 0.195 μg/L, and 0.488 μg/L. These concentrations were chosen as for their environmental relevance since they are close to the real concentrations of these pharmaceuticals found in surface waters and effluents. This work aims to characterize the effects of both drugs in zebrafish embryos and larvae, not only in developmental and behaviour parameters, but also using a biomarker-based approach, namely by quantifying the activities of catalase (CAT), glutathione-S-transferase (GST’s), cholinesterases (ChE’s), glutathione peroxidase (GPx), and determining the TBARS level. Exposure to paracetamol caused an increase in the percentage of organisms with morphological deformations, but no morphological deformations were observed in organisms exposed to ciprofloxacin. Concerning larvae behavioural tests, significant differences were observed for larvae exposed to paracetamol but not for larvae exposed to ciprofloxacin. In the biomarker determination, both drugs caused a statistically significant increase in ChE activity; in CAT only ciprofloxacin caused a significant difference, a decrease in its activity. Paracetamol induced an increase in activity for total GPx and in GST’s. The TBARS levels significantly increased in the exposure to paracetamol, but they significantly decreased in the exposure to ciprofloxacin. In this work, we also prepared an immunohistochemical detection of global methylation, which allowed to observe that, in embryos, the highest concentration of paracetamol caused a slight increase in the intensity of the 5- mdC signal, which can be translated into a slight increase in the DNA methylation. On the other hand, the embryos exposed to ciprofloxacin did not appear to have any difference from control. The comparison of the here-obtained results for the two different drugs allows observing that zebrafish larvae were more sensitive to the exposure to paracetamol, being the most sensitive methodology the biomarker determination. We can also conclude that oxidative stress occurred as a consequence of the exposure to both pharmaceuticals, being more evident in the case of paracetamol. We also showed that the oxidative stress created by the two pharmaceuticals may be the cause of all the other observations.
A presença de produtos farmacêuticos na natureza é uma questão emergente para a comunidade científica uma vez que estes compostos podem ter efeitos deletérios ou imprevisíveis sobre os organismos vivos. O estudo dos efeitos dos resíduos de medicamentos no ambiente evoluiu consideravelmente nos últimos anos, revelando que estes resíduos são uma ameaça para o ecossistema aquático. Dois exemplos de produtos farmacêuticos amplamente utilizados por humanos e presentes no meio ambiente são o paracetamol (acetaminofeno) e a ciprofloxacina. O paracetamol é um medicamento com propriedades analgésicas, utilizado para o alívio temporário da dor leve a moderada associada a gripes comuns, e na redução da febre. A ciprofloxacina é um antibiótico da classe química das fluoroquinolonas que apresenta um amplo espectro antibacteriano. Este trabalho tem como objetivo utilizar larvas de peixe-zebra e caracterizar os efeitos de ambos os medicamentos, não apenas nos parâmetros de desenvolvimento e comportamento, mas também usando com uma abordagem baseada em biomarcadores, nomeadamente quantificando as atividades de catalase (CAT), glutationa-S-transferase (GST), colinesterases (ChE's), glutationa peroxidase (GPx) e determinação do nível TBARS, bem como uma abordagem epigenética. Neste trabalho, também avaliamos por técnicas histoquímicas a metilação global do ADN. No caso do paracetamol, as concentrações testadas foram 0.005 mg/L, 0.025 mg/L, 0.125 mg/L, 0.625 mg/L, e 3.125 mg/L, juntamente com o controlo que apenas continha água do sistema. Para a ciprofloxacina, as concentrações testadas foram 0.005 μg/L, 0.013 μg/L, 0.031 μg/L, 0.078 μg/L, 0.195 μg/L, e 0.488 μg/L. Estas concentrações foram escolhidas pela sua relevância ambiental, uma vez que são muito próximas às concentrações destes fármacos no ambiente. A exposição ao paracetamol causou um aumento na percentagem de organismos com deformações morfológicas, mas não foram observadas deformações morfológicas em organismos expostos à ciprofloxacina. Quanto aos testes comportamentais com larvas de peixe-zebra, observaram-se diferenças significativas nas larvas expostas ao paracetamol, que demonstraram uma maior distância de natação, mas o mesmo efeito não foi observado para as larvas expostas à ciprofloxacina. Os dados obtidos para os diferentes biomarcadores demonstraram que ambos os fármacos causaram um aumento estatisticamente significativo na atividade de ChE. Na actividade da CAT, apenas a ciprofloxacina causou diferença significativa, mais propriamente uma descida na atividade da CAT. O paracetamol induziu um aumento na atividade da GPx total e das GSTs. Os níveis de TBARS aumentaram significativamente após exposição ao paracetamol, mas diminuíram significativamente em organismos expostos à ciprofloxacina. Os dados relativos à quantificação da metilação global do ADN permitiram observar que, em embriões, a maior concentração de paracetamol causou um ligeiro aumento na intensidade do sinal do marcador de metilação de ADN (5- mdC,) quando observado por miscroscopia de confocal. Por outro lado, os embriões expostos à ciprofloxacina não aparentavam ter qualquer diferença no perfil deste marcador de epigenética comparativamente ao controlo. A comparação dos resultados aqui obtidos para os dois fármacos diferentes permite observar que as larvas de peixe zebra eram mais sensíveis à exposição ao paracetamol, sendo a metodologia mais sensível a determinação do biomarcador. Também podemos concluir que o estresse oxidativo ocorreu como conseqüência da exposição a ambos os produtos farmacêuticos, sendo mais evidente no caso do paracetamol. Também mostramos que o estresse oxidativo criado pelos dois produtos farmacêuticos pode ser a causa de todas as outras observações.

Les hydrocarbures aromatiques polycycliques (HAP) sont des polluants ubiquistes dont le niveau d’émission est en constante augmentation en raison de l’intensification des activités anthropiques. Ces composés semi-persistants dans l’environnement représentent une menace pour les organismes. La santé et l’équilibre des systèmes naturels sont essentiels au maintien de la vie et au fonctionnement de la société. L’évaluation de l’impact de ces composés est alors devenue un véritable enjeu sociétal, établissant ainsi des mesures européennes législatives (Directive Cadre sur l’Eau) et réglementaires (REACH, enregistrement, évaluation, autorisation et restriction de produits chimiques) pour une meilleure gestion des risques (éco)toxicologiques. Dans ce contexte, de nombreux biotests ont vu le jour afin d’évaluer la dangerosité des substances chimiques (ou de leurs mélanges), la qualité du milieu environnant et de comprendre les mécanismes d’action toxique sur les organismes. L’objectif de cette étude était alors de définir les risques (éco)toxicologiques liés à des expositions par les HAP à travers des tests embryo-larvaires de poisson, utilisant un modèle éprouvé, le poisson zèbre Danio rerio. Afin d’évaluer le transfert, le devenir et les effets toxiques de HAP, deux approches complémentaires (chimique et biologique) ont été utilisées. Les réponses biologiques induites ont été évaluées à différents niveaux d’intégration biologique, des réponses moléculaires (stress oxydatif, dommages à l’ADN, EROD) aux modifications comportementales (Réponse PhotoMotrice), en passant par des altérations morphologiques et physiologiques (rythme cardiaque). Parmi les trois voies de contamination utilisées, l’exposition par contact avec le sédiment ne s’est pas révélée appropriée pour l’évaluation de la toxicité de HAP, contrairement aux expositions par voie aqueuse à partir de fractions hydrosolubles de produits pétroliers, qui sont plus reproductibles, intégratives et révélatrices des effets toxiques à plusieurs échelles. Suite à ces expérimentations, le champ d’observation des effets induits devrait être élargi au-delà des temps normalisés par l’Organisation de Coopération et de Développement Économique afin de ne pas sous-estimer le caractère létal du ou des composé(s) exposés. De plus, notre étude multigénérationnelle a mis en évidence des perturbations physiologiques et comportementales chez la première génération de descendance issue de parents contaminés par voie trophique à trois extraits aromatiques d’origine pyrolytique et pétrogénique (lourd et léger). Bien que le transfert de la contamination n’a pas été révélé, les altérations observées (probablement dues à des modifications génétiques et épigénétiques) chez les stades précoces de poisson zèbre, pourraient avoir des conséquences néfastes sur la survie et le recrutement des populations. Les études multigénérationnelles constituent ainsi des approches intégrées pour l’évaluation de la toxicité des composés exposés et permettent de renforcer le caractère prédictif des effets. Ces études écotoxicologiques devraient être largement déployées afin d’évaluer le potentiel qu’une population exposée a pour se maintenir dans le futur
PAHs are ubiquitous widespread contaminants which emissions are overgrowing with increasing anthropogenic activities. These semi-persistent chemicals are threatening organisms in the environment. Ecosystems health and resilience are essential to life and societal functioning. Impact assessment of these chemicals is a real requirement for society thereby establishing the european legislative (DCE, Water Framework Directive) and regulations (REACH, Registration, Evaluation, Authorisation and Restriction of Chemicals) for better (eco)toxicological risk management. In this context, many bioassays have been developed to assess environmental quality, the toxicity of chemicals (including mixture) on organisms and its underlying mechanisms. This study aimed to identify (eco)toxicological risks in the context of fish embryo-larval assay, using a relevant and well-known model : the zebrafish Danio rerio. Two complementary approaches (chemical and biological) were used to assess transfer, fate and toxicity of PAHs. Induced-responses were evaluated at different levels of biological organization, from molecular (oxidative stress, DNA damage, EROD) to physiological (cardiac activity), behavioral (PhotoMotor Response) and morphological levels. Among the three exposure routes tested, the sediment contact exposure was not suitable for PAHs toxicity assessment. In contrast, exposures to water-accommodated fractions (WAF) of petroleum products represented a more reproducible, sensitive and integrative approach for testing multiscale toxic effects. Following these experiments, the observation scope of induced effects should be broadened beyond the standard duration recommended by the Organization for Economic Cooperation and Development in order not to underestimate the acute effect of the tested-compounds. Furthermore, our multigenerational study showed physiological and behavioral disturbances on the first generation of offspring providing from parents exposed to contaminated-food with three aromatic extracts pyrolytic and petrogenic origin (heavy and light). Although the contamination transfer of PAHs has not been revealed, the observed alterations (probably due to a transfer through genetic and epigenetic modifications) in the early stages of zebrafish could have adverse effects on survival and recruitment populations. Multigenerational studies prove to be an integrated approach for the toxicity assessment of chemicals and strengthen the predictive effects. These ecotoxicological studies should be widely undertaken to evaluate the potential for exposed-population to maintain in the future time

Abstract With its emergence as a popular model system in developmental genetic studies, the zebrafish, Dania rerio (Teleostei,Cyprinidae), needs accurate anatomical descriptions and guides to staging (1). Staging by morphology helps resolve the problem of asynchrony during development and provides better accuracy in developmental analyses. There is a staging series for the embryonic period in zebrafish (2), but not for larvae and adults. This chapter brings together information on larval and adult morphology, most of which has been published separately in experimental papers. Although not a detailed staging series or atlas, it is meant to serve as a brief guide to late stages of zebrafish development in the laboratory, and to summarize knowledge and publications on zebrafish anatomy.

This chapter provides an overview of the zebrafish (Danio rerio) as a model organism for studies of mitochondrial dysfunction. Zebrafish possess a genetic similarity with humans and have conserved mitochondrial genomes, rendering them a valuable research tool for examining the intricate mechanisms that govern mitochondrial processes at diverse developmental stages. The chapter explores several methods for evaluating mitochondrial health and function. Examples include in vitro cell culture and in vivo analysis in embryos, larvae, and adults. The chapter discusses the use of zebrafish models in toxicological research to investigate mitochondrial reactions to environmental stressors and xenobiotics. The importance of implementing standardized protocols, validating marker, integrating different omics data, and using in vivo and in vitro approaches to advance mitochondrial research will be highlighted. In summary, zebrafish are suitable for analyzing both mitochondrial function and dysfunction, as well as their impact on human health.

Fishes often exhibit stable body undulating in body and caudal fin (BCF) mode during cyclic swimming, but can perform remarkable maneuverability with significantly different swimming modes in case of C-start. Aiming at unveiling the mechanisms of swimming hydrodynamics and maneuverability of C-start, we have developed an integrated computational framework to model a free-swimming larval zebrafish (Danio rerio) by coupling the equations of 3DoF (Degrees of Freedom) motion and Navier-Stokes (NS) equations. Unsteady hydrodynamics is resolved by integrating models of realistic fin-body morphology and body-undulatory kinematics with an in-house NS solver. The instantaneous forces and moments on the body provided by the NS-solutions serve as input for 3DoF equations of motion. In this study, with a specific focus on a C- start as well as a subsequent transient phase till the cyclic swimming phase, we construct a larval zebrafish model, which can mimics realistic body motions and deformations based on measurements. Validation of the simulation is discussed by comparing model predictions with experimental measurements, which indicates that the present integrated model is capable to accurately predict free-swimming dynamics and hydrodynamics. The model successfully simulated a swimming bout of C-start and cyclic swimming: a wake topology of double row vortex ring structures is observed behind the fish; and a strong jet is visible at the center of the vortex ring, pushing water backward as the fish accelerates.

All living organisms that inhabit Earth have evolved under a common value of gravity, which amounts to an acceleration of 9.81 m/s2 at mean sea level. Changes on it could cause important alterations that affect vital biological functions. The crescent interest in spatial exploration has opened the question of how exactly these changes in gravity would affect Earth life forms on space environments. This work is the result of a collaborative co-supervision of a master thesis between experts in the area of space sciences and biology, and it can serve as a case study for training experts in such interdisciplinary environments. In particular, we focus on the effect of gravity as a pressure factor in the development of zebrafish (Danio rerio) in the larval stage as a model organism using up-to-date (genomic and epigenetic) techniques. Given the high cost of any experiment in true low gravity (which would require a space launch), we performed an initial experiment in hypergravity to develop the methodologies and identify good (epi)genetic markers of the effect of gravity in our model organism. Previous studies in zebrafish have shown how alteration in gravity effects the development and the gene expression of important regulatory genes. For this study, we firstly customized a small laboratory scale centrifuge to study changes in fish physiology together with changes at molecular levels. We exposed zebrafish larvae from 0 to 6 days post fertilization to the simulated hypergravity (SHG) (100 rpm  3g). After 6 days of hypergravity exposition the larvae showed changes in their swimming and flotation patterns, and presented corporal alterations. Then, we assessed gene expression of genes implicated in important biological processes, (e.g., epigenetics), and an upregulation were observed when compared to the control. Taken together, these preliminary findings show how gravity alterations could affect some basic biological responses, and illustrate the potential of developing new science cases to be developed by students at postgraduate level (MSc and beyond) in a multidisciplinary environment