18 research outputs found
Cholinesterase activities as potential biomarkers: Characterization in two freshwater snails, Potamopyrgus antipodarum (Mollusca, Hydrobiidae, Smith 1889) and Valvata piscinalis (Mollusca, Valvatidae, MĂŒller 1774)
The effects of radionuclides on animal behavior.
International audienceConcomitant with the expansion of the nuclear industry, the concentrations of several pollutants, radioactive or otherwise, including uranium, caesium, cadmium and cobalt, have increased over the last few decades. These elemental pollutants do exist in the environment and are a threat to many organisms. Behavior represents the integration of all the anatomical adaptations and physiological processes that occur within an organism. Compared to other biological endpoints, the effects of pollutants on animal behavior have been the focus of only a few studies. However, behavioral changes appear to be ideal for assessing the effects of pollutants on animal populations, because behavior links physiological functions with ecological processes. The alteration of behavioral responses can have severe implications for survival of individuals and of population of some species. Behavioral disruptions may derive from several underlying mechanisms: disruption of neuro-sensorial activity and of endocrines, or oxidative and metabolic disruptions. In this review, we presented an overview of the current literature in which the effects of radioactive pollutants on behavior in humans, rodents, fish and wildlife species are addressed. When possible, we have also indicated the potential underlying mechanisms of the behavioral alterations and parameters measured. In fried, chronic uranium contamination is associated with behavior alterations and mental disorders in humans, and cognitive deficits in rats. Comparative studies on depleted and enriched uranium effects in rats showed that chemical and radiological activities of this metal induced negative effects on several behavioral parameters and also produced brain oxidative stress. Uranium exposure also modifies feeding behavior of bivalves and reproductive behavior of fish. Studies of the effects of the Chernobyl accident shows that chronic irradiation to 137Cs induces both nervous system diseases and mental disorders in humans leading to increased suicides, as well as modification of preferred nesting sites, reduced hatching success and fecundity in birds that live in the Chernobyl zone. No significant effect from caesium exposure was shown in laboratory experiments with rats, but few studies were conducted. Data on radioactive cadmium are not available in the literature, but the effects of its metallic form have been well studied. Cadmium induces mental retardation and psychomotor alterations in exposed populations and increases anxiety in rats, leading to depression. Cadmium exposure also results in well-documented effects on feeding and burrowing behavior in several invertebrate species (crustaceans, gastropods, annelids, bivalves) and on different kinds of fish behavior (swimming activity, fast-start response, antipredatory behavior). Cobalt induces memory deficits in humans and may be involved in Alzheimer's disease; gamma irradiation by cobalt also decreases fecundity and alters mating behavior in insects. Collectively, data are lacking or are meagre on radionuclide pollutants, and a better knowledge of their actions on the cellular and molecular mechanisms that control animal behavior is needed
Population-specific variations of the genetic architecture of sex determination in wild European sea bass Dicentrarchus labrax L.
Among the different sex determination modalities exhibited by fish species, polygenic sex determination (PSD) may show variations in terms of genetic and environmental components between populations exposed/adapted to different environments. European sea bass (Dicentrarchus labrax) is an interesting model, combining both a PSD system and a genetic subdivision into an Atlantic and a Mediterranean lineage, with genetic substructures within the Mediterranean Sea. We produced experimental progeny crosses (N = 927) from broodstock sampled in four wild populations (North Atlantic, NAT; Western Mediterranean, WEM; North-Eastern Mediterranean, NEM; South-Eastern Mediterranean, SEM). There were less females than males in the progeny, both in the global dataset (32.5%) and within each paternal group (from 25.1% for NEM to 39.0% for WEM), with significant variation among populations, dams and sires. Sex, body weight (BW) and body length (BL) showed moderate heritability (0.52 ± 0.17, 0.46 ± 0.17, 0.34 ± 0.15, respectively). Sex was genetically correlated with BW and BL (rA sex/BW = 0.69 ± 0.12, rA sex/BL = 0.66 ± 0.13).
The wGWAS performed both on the global dataset and within each paternal group revealed a different genetic architecture of sex determination between Atlantic and Mediterranean populations (9 QTLs found in NAT, 7 in WEM, 5 in NEM and 4 in SEM, with a cumulated variance explained of 27.04%, 21.87%, 15.89% and 12.10%, respectively) with a more similar genetic architecture among geographically close populations compared to geographically distant populations, consistent with the hypothesis of a population-specific evolution of polygenic sex determination systems in different environments
Multigenerational exposure to gamma radiation affects offspring differently over generations in Zebrafish
International audienceMutigenerational studies have become of great interest in ecotoxicology and previously provided original results on the effects of offspring irradiation in model fish Danio rerio. Here, the irradiation of zebrafish was maintained until F2 larval stage. Two dose rates were selected; the first one (0.05 mGy h-1) was close to the threshold value for the protection of aquatic ecosystems, the second one (5 mGy h-1) previously studied and known to increase morbidity (DCRL). F1 from 30d-irradiated parents were irradiated themselves (irradiated condition) or not (Recovery condition) for 131 days before reproduction. Endpoints concerned reproductive capacity (reproductive success, fecundity, egg fertilization) and larval survival in F0, F1 and F2. Multigenerational irradiation affected F1 parental reproductive capacity mainly over the first reproduction and larval survival rate. Unexpected effects on sex ratio was observed in exposed and non-exposed F1 progeny after parental irradiation (mainly at 5 mGy h-1). The worsening effects over the two generations observed here could partly explain the higher sensitivity of wild populations. Thus, this study confirm that multigenerational studies could be of interest on ecological risk assessment, in particular to determine the benchmark values
Tritiated Water Exposure in Zebrafish (Danio rerio): Effects on the EarlyâLife Stages
International audienceTritium, a radioactive isotope of hydrogen of natural and anthropogenic origin, is ubiquitously present in theenvironment. Effluents of nuclear centers of production are significant anthropogenic sources. With the upcoming project of thermonuclear fusion, tritium releases in the environment may increase. It is therefore important to characterize the ecologicalrisk linked to tritium. The effects of tritiated water (HTO) were therefore studied in zebrafish larvae exposed for 10 d todifferent dose rates, 1.1 Ă 102, 4.1 Ă 102, and 3.8 Ă 103 ÎŒGy/h for larvae corresponding, respectively, to a water contaminationof 104, 105, and 106 Bq/mL of HTO. Those dose rates were higher than 10 ÎŒGy/h, which is the threshold recommended tostart monitoring ecosystems where radiological contaminants are present. Mortality, embryoâlarval development, immune toxicity, genotoxicity, neurotoxicity, and alterations of tissues were investigated. The results showed that HTO exposure induced DNA damage and reactive oxygen species production and modulated the expression of genes involved in detoxificationprocesses. Moreover, modifications of the muscular tissues (degradation of myofibrils at 4 d post fertilization anddisorganization of mitochondria at later stages) were observed. The results differed with HTO dose rates and with developmentalstages. These results will drive future research for the development of new HTOâsensitive biomarkers and willallow us to progress in the characterization of the modes of action of tritium in fish
Effects of gamma ionizing radiation exposure on Danio rerio embryo-larval stages - comparison with tritium exposure
International audienceThe objective was to investigate the effects of ionizing radiation induced in zebrafish early life stages by coupling responses obtained at the molecular (genotoxicity, ROS production, gene expression) and phenotypic (tissue alteration, embryo-larval development) levels. Here we present results obtained after exposure of 3 hpf larvae to 10 days of gamma irradiation at 3.3x101, 1.3x102 and 1.2x103 ”Gy/h. Dose rates used in these studies were chosen to be in the âderived consideration reference levelâ (DCRL) for gamma irradiation where deleterious effects can appear in freshwater fish. Also, these dose rates were similar to the ones already tested on tritium (beta ionizing radiation) in our previous work, in order to compare both types of ionizing radiation. Results showed that gamma irradiation did not induce any effect on survival and hatching. No effect was observed on DNA damages, but ROS production was increased. Muscle damages were observed for all tested dose rates, similarly to previous results obtained with tritium (beta ionizing radiation) at similar dose rates. Some molecular responses therefore appeared to be relevant for the study of gamma ionizing radiation effects in zebrafish
Effets du tritium in vivo et in situ sur la santé des poissons : approche multi biomarqueurs et liens entre les échelles biologiques
International audienceLe contexte des effets biologiques de lâexposition aux rayonnements ionisants est une prĂ©occupation majeure pour la radioprotection de lâhomme et de lâenvironnement. Ceci a rĂ©cemment Ă©tĂ© mis en exergue aprĂšs lâaccident de Fukushima, notamment dans le contexte de la quantification du risque pour la santĂ© des individus et populations exposĂ©es aux faibles doses. Augmenter la connaissance des effets des faibles doses sur les espĂšces humaines et non-humaines permettrait de gagner en prĂ©cision pour la prĂ©diction des effets et la prise de dĂ©cision.Lâindustrie nuclĂ©aire rejette dans lâenvironnement diffĂ©rents types de radionuclĂ©ides, principalement des Ă©metteurs gamma (137Cs, 60Co, 54Mn), mais aussi du tritium, le plus important en termes de production (200g correspondant Ă 7,2.106 Bq/an dans le monde). Le tritium est un isotope radioactif de lâhydrogĂšne qui Ă©met des rayonnements beta. Sa demi-vie est de 12,3 ans. Les rejets de tritium sont supposĂ©s augmenter dans le futur avec le dĂ©veloppement de rĂ©acteurs basĂ©s sur la fusion nuclĂ©aire (ITER). Les Ă©cosystĂšmes aquatiques, habitĂ©s pas de nombreuses espĂšces animales et vĂ©gĂ©tales, reprĂ©sentent gĂ©nĂ©ralement le rĂ©cepteur final dâun grand nombre de polluants, incluant des radionuclĂ©ides dont le tritium. Lâexposition Ă des niveaux Ă©levĂ©s de radionculĂ©ides est connue pour induire de nombreuses altĂ©rations sur diffĂ©rentes fonctions de lâorganisme, de la molĂ©cule (intĂ©gritĂ© de lâADN) Ă la population (effets sur la survie et la reproduction). Cependant, les effets de faibles niveaux dâexposition, plus pertinents dâun point de vue environnemental, sont peu connus.Cette prĂ©sentation rĂ©sume les diffĂ©rents travaux menĂ©s depuis plusieurs annĂ©es Ă lâIRSN sur le tritium, sur diffĂ©rents modĂšles biologiques : le poisson zĂšbre, Danio rerio, espĂšce modĂšle facile Ă maintenir en laboratoire, afin de comprendre les mĂ©canismes dâaction du tritium dans le cadre dâexpositions contrĂŽlĂ©es ; et le tĂȘte de boule, Pimephales promelas, espĂšce autochtone du continent Nord-AmĂ©ricain, afin dâĂ©tudier les effets du tritium seul ou un mĂ©lange dans un contexte rĂ©el de contamination aux effluents dâun centre de recherche. LâĂ©valuation des effets du tritium a Ă©tĂ© rĂ©alisĂ©e par lâanalyse dâune batterie de biomarqueurs Ă diffĂ©rentes Ă©chelles biologiques, de la molĂ©cule Ă lâindividu. Lâanalyse de lâensemble des rĂ©sultats permettra de mieux comprendre les effets du tritium, seul ou en mĂ©lange, sur la physiologie du poisson
Effets du tritium in vivo et in situ sur la santé des poissons : approche multi biomarqueurs et liens entre les échelles biologiques
International audienceLe contexte des effets biologiques de lâexposition aux rayonnements ionisants est une prĂ©occupation majeure pour la radioprotection de lâhomme et de lâenvironnement. Ceci a rĂ©cemment Ă©tĂ© mis en exergue aprĂšs lâaccident de Fukushima, notamment dans le contexte de la quantification du risque pour la santĂ© des individus et populations exposĂ©es aux faibles doses. Augmenter la connaissance des effets des faibles doses sur les espĂšces humaines et non-humaines permettrait de gagner en prĂ©cision pour la prĂ©diction des effets et la prise de dĂ©cision.Lâindustrie nuclĂ©aire rejette dans lâenvironnement diffĂ©rents types de radionuclĂ©ides, principalement des Ă©metteurs gamma (137Cs, 60Co, 54Mn), mais aussi du tritium, le plus important en termes de production (200g correspondant Ă 7,2.106 Bq/an dans le monde). Le tritium est un isotope radioactif de lâhydrogĂšne qui Ă©met des rayonnements beta. Sa demi-vie est de 12,3 ans. Les rejets de tritium sont supposĂ©s augmenter dans le futur avec le dĂ©veloppement de rĂ©acteurs basĂ©s sur la fusion nuclĂ©aire (ITER). Les Ă©cosystĂšmes aquatiques, habitĂ©s pas de nombreuses espĂšces animales et vĂ©gĂ©tales, reprĂ©sentent gĂ©nĂ©ralement le rĂ©cepteur final dâun grand nombre de polluants, incluant des radionuclĂ©ides dont le tritium. Lâexposition Ă des niveaux Ă©levĂ©s de radionculĂ©ides est connue pour induire de nombreuses altĂ©rations sur diffĂ©rentes fonctions de lâorganisme, de la molĂ©cule (intĂ©gritĂ© de lâADN) Ă la population (effets sur la survie et la reproduction). Cependant, les effets de faibles niveaux dâexposition, plus pertinents dâun point de vue environnemental, sont peu connus.Cette prĂ©sentation rĂ©sume les diffĂ©rents travaux menĂ©s depuis plusieurs annĂ©es Ă lâIRSN sur le tritium, sur diffĂ©rents modĂšles biologiques : le poisson zĂšbre, Danio rerio, espĂšce modĂšle facile Ă maintenir en laboratoire, afin de comprendre les mĂ©canismes dâaction du tritium dans le cadre dâexpositions contrĂŽlĂ©es ; et le tĂȘte de boule, Pimephales promelas, espĂšce autochtone du continent Nord-AmĂ©ricain, afin dâĂ©tudier les effets du tritium seul ou un mĂ©lange dans un contexte rĂ©el de contamination aux effluents dâun centre de recherche. LâĂ©valuation des effets du tritium a Ă©tĂ© rĂ©alisĂ©e par lâanalyse dâune batterie de biomarqueurs Ă diffĂ©rentes Ă©chelles biologiques, de la molĂ©cule Ă lâindividu. Lâanalyse de lâensemble des rĂ©sultats permettra de mieux comprendre les effets du tritium, seul ou en mĂ©lange, sur la physiologie du poisson
Effets du tritium in vivo et in situ sur la santé des poissons : approche multi biomarqueurs et liens entre les échelles biologiques
International audienceLe contexte des effets biologiques de lâexposition aux rayonnements ionisants est une prĂ©occupation majeure pour la radioprotection de lâhomme et de lâenvironnement. Ceci a rĂ©cemment Ă©tĂ© mis en exergue aprĂšs lâaccident de Fukushima, notamment dans le contexte de la quantification du risque pour la santĂ© des individus et populations exposĂ©es aux faibles doses. Augmenter la connaissance des effets des faibles doses sur les espĂšces humaines et non-humaines permettrait de gagner en prĂ©cision pour la prĂ©diction des effets et la prise de dĂ©cision.Lâindustrie nuclĂ©aire rejette dans lâenvironnement diffĂ©rents types de radionuclĂ©ides, principalement des Ă©metteurs gamma (137Cs, 60Co, 54Mn), mais aussi du tritium, le plus important en termes de production (200g correspondant Ă 7,2.106 Bq/an dans le monde). Le tritium est un isotope radioactif de lâhydrogĂšne qui Ă©met des rayonnements beta. Sa demi-vie est de 12,3 ans. Les rejets de tritium sont supposĂ©s augmenter dans le futur avec le dĂ©veloppement de rĂ©acteurs basĂ©s sur la fusion nuclĂ©aire (ITER). Les Ă©cosystĂšmes aquatiques, habitĂ©s pas de nombreuses espĂšces animales et vĂ©gĂ©tales, reprĂ©sentent gĂ©nĂ©ralement le rĂ©cepteur final dâun grand nombre de polluants, incluant des radionuclĂ©ides dont le tritium. Lâexposition Ă des niveaux Ă©levĂ©s de radionculĂ©ides est connue pour induire de nombreuses altĂ©rations sur diffĂ©rentes fonctions de lâorganisme, de la molĂ©cule (intĂ©gritĂ© de lâADN) Ă la population (effets sur la survie et la reproduction). Cependant, les effets de faibles niveaux dâexposition, plus pertinents dâun point de vue environnemental, sont peu connus.Cette prĂ©sentation rĂ©sume les diffĂ©rents travaux menĂ©s depuis plusieurs annĂ©es Ă lâIRSN sur le tritium, sur diffĂ©rents modĂšles biologiques : le poisson zĂšbre, Danio rerio, espĂšce modĂšle facile Ă maintenir en laboratoire, afin de comprendre les mĂ©canismes dâaction du tritium dans le cadre dâexpositions contrĂŽlĂ©es ; et le tĂȘte de boule, Pimephales promelas, espĂšce autochtone du continent Nord-AmĂ©ricain, afin dâĂ©tudier les effets du tritium seul ou un mĂ©lange dans un contexte rĂ©el de contamination aux effluents dâun centre de recherche. LâĂ©valuation des effets du tritium a Ă©tĂ© rĂ©alisĂ©e par lâanalyse dâune batterie de biomarqueurs Ă diffĂ©rentes Ă©chelles biologiques, de la molĂ©cule Ă lâindividu. Lâanalyse de lâensemble des rĂ©sultats permettra de mieux comprendre les effets du tritium, seul ou en mĂ©lange, sur la physiologie du poisson
Insights into the modes of action of tritium on the early-life stages of zebrafish, Danio rerio, using transcriptomic and proteomic analyses
International audienceIn the environment, populations are exposed to different kinds of ionizing radiation. Little is known about their modes of action on non-human species, and whether or not they are similar for alpha, beta and gamma radiations, considered as the reference. In this context, tritium effects (beta emitter) under the form of tritiated water (HTO) were investigated in zebrafish, a common model in toxicology and ecotoxicology with a fully sequenced genome. Experiments were conducted on early life stages, considered to be highly sensitive to pollutants, byexposing eggs to 0.4 mGy/h of HTO until 10 days post fertilization. Tritium internalization was quantified, and effects were investigated using a combined approach of transcriptomic and proteomic analyses. Results highlighted similarities in the biological pathways affected by HTO by both techniques, such as defence response, muscle integrity and contraction, and potential visual alterations. These results correlated well with previous data obtained on earlier developmental stages (1 and 4 dpf). Interestingly, HTO effects were partly overlapping those obtained after gamma irradiation, underlying potential common modes of action. This study, therefore, brought a body of evidence on the effects of HTO observed at the molecular level on zebrafish larvae. Furtherstudies could investigate if the effects persist in adult organisms