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Michel Jangoux - One of the best experts on this subject based on the ideXlab platform.
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optimization of gonad growth by manipulation of temperature and photoperiod in cultivated sea urchins Paracentrotus lividus lamarck echinodermata
Aquaculture, 2000Co-Authors: Christine Spirlet, Philippe Grosjean, Michel JangouxAbstract:A starvation and then feeding method was developed to produce about 100% marketable sea urchins, Paracentrotus lividus, in 3 1/2 months. This method is needed because the reproduction cycle is desynchronized in the conditions imposed during the somatic growth stage in land-based closed systems. The major advantages of starving the animals are resetting the reproductive cycle to the spent stage (gonads almost devoid of sexual cells) and stressing the individuals so that they mobilize and restore the nutritive phagocytes, filling them with nutrients. Batches of sea urchins starved 2 months beforehand were fed ad libitum for 45 days with enriched food under eight combinations of four temperatures (12°C, 16°C, 20°C and 24°C) and two photoperiods (9 and 17 h daylight). In our system, the best combination was 24°C and 9 h daylight for growth as well as for gonad quality. The gonadal indices obtained (in dry weight) were over 9% at 16°C and over 12% at 24°C, which are better than what is found in the field for this population.
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spermiotoxicity and embryotoxicity of heavy metals in the echinoid Paracentrotus lividus
Environmental Toxicology and Chemistry, 1996Co-Authors: Michel Warnau, Michel Jangoux, Philippe Dubois, Ali Temara, M Iaccarino, Antonella De Biase, Giovanni PaganoAbstract:Spermio- and embryotoxicities of Cu, Ag, Cd, and Hg were investigated in Paracentrotus lividus, the dominant echinoid species of the Mediterranean. Spermiotoxicity was studied by assessing the effects of sperm exposure on fertilization rate (FR) as well as on the induction of transmissible damages to the offspring. Embryotoxicity was studied by assessing developmental defects in larvae exposed to the tested metals throughout their development. Sperm exposures resulted in significant decreases of FR, depending on both metal concentration and duration of the exposure. Lowest spermiotoxic concentrations recorded when sperm were exposed for 75 min to the metals were 10−7 M Hg(II), 10−6 M Ag(I), 10−5 M Cu(II), and 10−5 M Cd(II). Tested metals did not exert any transmissible damage to spermatozoa that could result in larval malformations in the offspring, even for concentrations that dramatically reduced FR. Single-element exposures of embryos for 72 h resulted in developmental defects whose occurrence and severity showed a steep dose dependence, indicating that once a threshold is reached, any further increase in toxicant concentration rapidly enhances the impairment of target function(s). Those observations suggest the involvement of a saturable protective mechanism. Lowest observed embryotoxic concentrations of the metals were 10−7 M Hg(II), 2.5 × 10−7 M Ag(I), 5 × 10−7 M Cu(II), and 10−5 M Cd(II) and are in the range of concentrations reported in heavily polluted marine environments. Thus, the possibility of impairment of echinoid development actually exists in metal-contaminated marine environments, possibly threatening echinoid populations in those environments.
Annamaria Volpi Ghirardini - One of the best experts on this subject based on the ideXlab platform.
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Toxicity of tributyltin and triphenyltin to early life-stages of Paracentrotus lividus (Echinodermata: Echinoidea).
Environmental Toxicology and Chemistry, 2002Co-Authors: Alessandra Arizzi Novelli, Emanuele Argese, Davide Tagliapietra, Cinzia Bettiol, Annamaria Volpi GhirardiniAbstract:Sperm cell and embryo toxicity tests using the Mediterranean sea urchin Paracentrotus lividus were performed to assess the toxicity of tributyltin chloride, bis(tributyltin)oxide, triphenyltin acetate, and triphenyltin hydroxide. Toxicity values (mean effective concentration [EC50]) ranged from 2.97 to 18.5 μg/L for sperm cells and from 1.11 to 2.62 μg/L for embryos. For sperm cells, the toxicity of the two tributyl compounds was significantly greater than that of two triphenyl compounds; for embryos, the triphenyl compounds appeared to be more toxic. Study of embryotoxic effects highlighted closely concentration-dependent damages, the most sensitive stages corresponding to the crucial phases of differentiation (gastrula and prisma). Both EC50 and no-observed-effect concentration values for the four organotin compounds are similar to those reported in the literature for early life stages of other marine organisms.
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sperm cell toxicity test using sea urchin Paracentrotus lividus lamarck echinodermata echinoidea sensitivity and discriminatory ability toward anionic and nonionic surfactants
Environmental Toxicology and Chemistry, 2001Co-Authors: Annamaria Volpi Ghirardini, Alessandra Arizzi Novelli, Barbara Likar, Giulio Pojana, Pier Francesco Ghetti, Antonio MarcominiAbstract:A reliable sperm cell toxicity test procedure has been developed for the Mediterranean sea urchin Paracentrotus lividus. The sensitivity and discriminatory ability of the test were investigated with regard to surfactants and their biotransformation products. Aromatic and aliphatic surfactants of anionic (linear alkylbenzene sulfonates [LAS]) and nonionic (alcohol polyethoxylates [AE] and nonylphenol polyethoxylates [NPE]) types and their aerobic biodegradation products, i.e., sulfophenylcarboxylates (SPC), polyethylene glycols (PEG), carboxylated polyethylene glycols (PEGC), carboxylated AE (AEC), and nonylphenol (NP), were examined in order to elucidate the influence of their molecular structure on toxicity. Experimental results reveal that the sperm cell test showed good discriminatory ability among all tested compounds, median effective concentration (EC50) values differing by about four orders of magnitude. The toxicity of anionic surfactants depends on the length of the alkyl chain and that of nonionic surfactants is due to their length and branching. Much lower toxicity was shown by aerobic biodegradation products in comparison with that of their parent compounds, with the exception of NP. The obtained EC50s were comparable with available literature data and constitute new toxicity data regarding surfactants for sea urchins.
Vincenzo Arizza - One of the best experts on this subject based on the ideXlab platform.
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stress and immune response to bacterial lps in the sea urchin Paracentrotus lividus lamarck 1816
Fish & Shellfish Immunology, 2019Co-Authors: Marco Chiaramonte, Luigi Inguglia, Mirella Vazzana, Alan Deidun, Vincenzo ArizzaAbstract:Abstract The immune system of the sea urchin species Paracentrotus lividus is highly complex and, as yet, poorly understood. P. lividus coelomocytes mediate immune response through phagocytosis and encapsulation of non-self particles, in addition to the production of antimicrobial molecules. Despite this understanding, details of exactly how these processes occur and the mechanisms which drive them are still in need of clarification. In this study, we show how the bacterial lipopolysaccharides (LPS) is able to induce a stress response which increases the levels of the heat shock proteins HSP70 and HSP90 only a few hours after treatment. This study also shows that LPS treatment increases the expression of the β-thymosin-derivated protein paracentrin, the precursor of antimicrobial peptides.
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antimicrobial and antistaphylococcal biofilm activity from the sea urchin Paracentrotus lividus
Journal of Applied Microbiology, 2010Co-Authors: Domenico Schillaci, Vincenzo Arizza, Nicolo Parrinello, V Di Stefano, Serena Fanara, Vera Muccilli, Vincenzo Cunsolo, Janus A J Haagensen, Soren MolinAbstract:Aims: Staphylococcal biofilm-associated infections are resistant to conventional antibiotics. Consequently, new agents are needed to treat them. With this aim, we focused on the effector cells (coelomocytes) of the sea urchin Paracentrotus lividus immune system. Methods and Results: We tested the activity of the 5-kDa peptide fraction of the cytosol from coelomocytes (5-CC) against a group of Gram-positive, Gram-negative bacteria and fungi. We determined minimal inhibitory concentrations (MICs) ranging from 253·7 to 15·8 mg ml−1. We observed an inhibitory activity and antibiofilm properties of 5-CC against staphylococcal biofilms of reference strains Staphylococcus epidermidis DSM 3269 and Staphylococcus aureus ATCC 29213. The antimicrobial efficacy of 5-CC against the biofilms of clinical strain Staph. epidermidis 1457 was also tested using live/dead staining in combination with confocal laser scanning microscopy. At a sub-MIC concentration (31·7 mg ml−1) of 5-CC the formation of young (6-h old) and mature (24-h old) staphylococcal biofilms was inhibited. Conclusions: The biological activity of 5-CC could be attributed to three peptides belonging to the sequence segment 9–41 of a beta-thymosin of P. lividus. Significance and Impact of the Study: The effector cells of P. lividus represent an interesting source of marine invertebrates-derived antimicrobial agents in the development of new strategies to treat staphylococcal biofilms.
Ricardo Beiras - One of the best experts on this subject based on the ideXlab platform.
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Ecotoxicological Evaluation of the UV Filters Ethylhexyl Dimethyl p -Aminobenzoic Acid and Octocrylene Using Marine Organisms Isochrysis galbana , Mytilus galloprovincialis and Paracentrotus lividus
Archives of environmental contamination and toxicology, 2017Co-Authors: A. Giraldo, Rosa Montes, Rosario Rodil, José Benito Quintana, Leticia Vidal-liñán, Ricardo BeirasAbstract:The growing concern regarding the negative effects of solar radiation on the skin has led to a drastic increase in the use of sunscreens containing in its composition up to 10% of aromatic chemicals, such as ethylhexyl dimethyl p-aminobenzoic acid (OD-PABA) and octocrylene (OC). The objective of this study was to evaluate the toxicity and to assess the environmental risk posed by these two ultraviolet filters, widely used in cosmetics and as plastic additives, in the marine environment. Several ecotoxicological bioassays were performed with three model organisms belonging to different trophic levels: the microalgae Isochrysis galbana, the mussel Mytilus galloprovincialis, and the sea urchin Paracentrotus lividus. The results show remarkable toxicity to marine species for both OD-PABA (EC10 values range 26,5–127 µg L−1) and OC (EC10 range 103–511 µg L−1). The cell division in the microalgae I. galbana was the most sensitive endpoint tested. To determine the environmental risk of these substances, the risk coefficient (RQ) was calculated. Due to the higher concentrations reported, OC showed remarkable risk (RQ = 0.27), whereas for OD-PABA the risk was low (RQ = 0.007).
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embryotoxicity of the antifouling biocide zinc pyrithione to sea urchin Paracentrotus lividus and mussel mytilus edulis
Marine Pollution Bulletin, 2005Co-Authors: Juan Bellas, Ake Granmo, Ricardo BeirasAbstract:The effects of the new antifouling compound zinc pyrithione (Zpt) on the embryonic development of sea urchin (Paracentrotus lividus) and mussel (Mytilus edulis) were investigated in laboratory toxicity tests. The median effective concentrations (EC50) were 7.7 nM for sea urchin embryos and 8 nM for mussel embryos. Toxic effects of Zpt on the larval growth of the sea urchin were detected at 0.5 nM. Predicted environmental concentrations of Zpt in pleasure craft harbours are higher than the predicted no effect concentrations for sea urchin and mussel embryos, indicating that Zpt may pose a threat to those species from exposure in the field.
Stéphane Coupé - One of the best experts on this subject based on the ideXlab platform.
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Assessment of individual and mixed toxicity of bromoform, tribromoacetic-acid and 2,4,6 tribromophenol, on the embryo-larval development of Paracentrotus lividus sea urchin
Environmental Science and Pollution Research, 2019Co-Authors: Karine Lebaron, Lilia Mechiri, Simone Richard, Annabelle Austruy, Jean-luc Boudenne, Stéphane CoupéAbstract:Water chlorination is the most widely used technique to avoid microbial contamination and biofouling. Adding chlorine to bromide-rich waters leads to the rapid oxidation of bromide ions and leads to the formation of brominated disinfection by-products (bromo-DBPs) that exert adverse effects on various biological models. Bromo-DBPs are regularly encountered within industrialized embayments, potentially impacting marine organisms. Of these, bromoform, tribromoacetic acid and tribromophenol are among the most prevalent. In the present study, we tested the potential toxicity and genotoxicity of these disinfection by-products, using sea urchin, Paracentrotus lividus, embryos. We highlighted that tribromophenol showed higher toxicity compared to bromoform and tribromoacetic acid. Furthermore, a synergistic effect was detected when tested in combination. Pluteus cells exposed for 1 h to mixtures of DBPs at several concentrations demonstrated significant DNA damage. Finally, when compared to a non-exposed population, sea urchins living in a bromo-DPB-polluted area produced more resistant progenies, as if they were locally adapted. This hypothesis remains to be tested in order to better understand the obvious impact of complex bromo-DBPs environments on marine wildlife.
