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Auteur Abadie, E.; Chiantella, C.; Crottier, A.; Rhodes, L.; Masseret, E.; Berteaux, T.; Laabir, M.
Titre What are the main environmental factors driving the development of the neurotoxic dinoflagellate Vulcanodinium rugosum in a Mediterranean ecosystem (Ingril lagoon, France)? Type Article scientifique
Année 2018 Publication Revue Abrégée Harmful Algae
Volume 75 Numéro Pages 75-86
Mots-Clés Development dynamic; Environmental factors; Ingril lagoon; Neurotoxins; Vulcanodinium rugosum
Résumé Vulcanodinium rugosum, a dinoflagellate developing in Ingril Lagoon (Mediterranean, France) is responsible for shellfish intoxications due to the neurotoxin pinnatoxin G. A one year survey (March 2012–April 2013) was conducted in this oligotrophic shallow lagoon and key environmental parameters were recorded (temperature, salinity and nutrients). The spatio-temporal distribution of V. rugosum in water column and on macrophytes was also determined. Planktonic cells of V. rugosum were observed at all sampling stations, but in relatively low concentrations (maximum of 1000 cell/L). The highest abundances were observed from June to September 2012. There was a positive correlation between cell densities and both temperature and salinity. Non-motile cells were detected on macrophytes, with a maximum concentration of 6300 cells/g wet weight. Nitrite and ammonium were negatively related to V. rugosum abundance whereas total nitrogen, total phosphorus and phosphates showed a positive correlation. Altogether, in situ results suggest that V. rugosum is rather thermophilic and that organic nutrients should be considered when studying the nutrition requirements for this noxious expanding dinoflagellate.
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Éditeur de collection Titre de collection Titre de collection Abrégé
Volume de collection Numéro de collection Edition
ISSN 1568-9883 ISBN Médium
Région Expédition Conférence
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Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2331
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Auteur Arnich, N.; Abadie, E.; Delcourt, N.; Fessard, V.; Fremy, J.-M.; Hort, V.; Lagrange, E.; Maignien, T.; Molgó, J.; Peyrat, M.-B.; Vernoux, J.-P.; Mattei, C.
Titre Health risk assessment related to pinnatoxins in French shellfish Type Article scientifique
Année 2020 Publication Revue Abrégée Toxicon
Volume Numéro Pages
Mots-Clés Emerging marine biotoxins; Pinnatoxins; Risk assessment; Shellfish
Résumé Pinnatoxins (PnTXs) are a group of emerging marine biotoxins produced by the benthic dinoflagellate Vulcanodinium rugosum, currently not regulated in Europe or in any other country in the world. In France, PnTXs were detected for the first time in 2011, in mussels from the Ingril lagoon (South of France, Mediterranean coast). Since then, analyses carried out in mussels from this lagoon have shown high concentrations of PnTXs for several months each year. PnTXs have also been detected, to a lesser extent, in mussels from other Mediterranean lagoons and on the Atlantic and Corsican coasts. In the French data, the main analog is PnTX G (low levels of PnTX A are also present in some samples). No cases of PnTXs poisoning in humans have been reported so far in France or anywhere else in the world. In mice, PnTXs induce acute neurotoxic effects, within a few minutes after oral administration. Clinical signs of toxicity include decreased mobility, paralysis of the hind legs, tremors, jumps and breathing difficulties leading to death by respiratory arrest at high doses. The French agency for food safety (ANSES) recently conducted a review of the state of knowledge related to PnTXs and V. rugosum. Based on (i) the clinical signs of toxicity in mice, (ii) the mode of action of PnTXs as nicotinic acetylcholine receptor competitive antagonists and (iii) knowledge on drugs and natural toxins with PnTX-related pharmacology, potential human symptoms have been extrapolated and proposed. In this work, a provisional acute benchmark value for PnTX G of 0.13 μg/kg bw per day has been derived from an oral acute toxicity study in mice. Based on this value and a large shellfish meat portion size of 400g, a concentration lower than 23 μg PnTX G/kg shellfish meat is not expected to result in adverse effects in humans. ANSES recommends taking into account PnTXs in the French official monitoring program for shellfish production and identified data gaps to refine health risk assessment.
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Langue en Langue du Résumé Titre Original
Éditeur de collection Titre de collection Titre de collection Abrégé
Volume de collection Numéro de collection Edition
ISSN 0041-0101 ISBN Médium
Région Expédition Conférence
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Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2742
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Auteur Ben Gharbia, H.; Yahia, O.K.-D.; Cecchi, P.; Masseret, E.; Amzil, Z.; Herve, F.; Rovillon, G.; Nouri, H.; M’Rabet, C.; Couet, D.; Triki, H.Z.; Laabir, M.
Titre New insights on the species-specific allelopathic interactions between macrophytes and marine HAB dinoflagellates Type Article scientifique
Année 2017 Publication Revue Abrégée Plos One
Volume 12 Numéro 11 Pages e0187963
Mots-Clés Dinoflagellates; Lagoons; Leaves; marine ecosystems; Phenols; Photosynthesis; Phytoplankton; Toxins
Résumé Macrophytes are known to release allelochemicals that have the ability to inhibit the proliferation of their competitors. Here, we investigated the effects of the fresh leaves of two magnoliophytes (Zostera noltei and Cymodocea nodosa) and thalli of the macroalgae Ulva rigida on three HAB-forming benthic dinoflagellates (Ostreopsis cf. ovata, Prorocentrum lima, and Coolia monotis). The effects of C. nodosa and U. rigida were also tested against the neurotoxic planktonic dinoflagellate Alexandrium pacificum Litaker sp. nov (former Alexandrium catenella). Co-culture experiments were conducted under controlled laboratory conditions and potential allelopathic effects of the macrophytes on the growth, photosynthesis and toxin production of the targeted dinoflagellates were evaluated. Results showed that U. rigida had the strongest algicidal effect and that the planktonic A. pacificum was the most vulnerable species. Benthic dinoflagellates seemed more tolerant to potential allelochemicals produced by macrophytes. Depending on the dinoflagellate/macrophyte pairs and the weight of leaves/thalli tested, the studied physiological processes were moderately to heavily altered. Our results suggest that the allelopathic activity of the macrophytes could influence the development of HAB species.
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Langue Langue du Résumé Titre Original
Éditeur de collection Titre de collection Titre de collection Abrégé
Volume de collection Numéro de collection Edition
ISSN 1932-6203 ISBN Médium
Région Expédition Conférence
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Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2242
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Auteur Caruana, A.M.N.; Le Gac, M.; Herve, F.; Rovillon, G.-A.; Geffroy, S.; Malo, F.; Abadie, E.; Amzil, Z.
Titre Alexandrium pacificum and Alexandrium minutum: Harmful or environmentally friendly? Type Article scientifique
Année 2020 Publication Revue Abrégée Mar. Environ. Res.
Volume 160 Numéro Pages 105014
Mots-Clés Algal toxins; catenella; complex dinophyceae; diatom; dimethylsulfide dms; dimethylsulfoniopropionate dmsp; dimethylsulphoniopropionate; Dinoflagellate; dmsp; dsyB gene; Glycine betaine; growth; Paralytic shellfish toxins; phytoplankton; Phytoplankton; pst; salinity; Salinity; Saxitoxin; shellfish toxin production
Résumé Alexandrium minutum and Alexandrium pacificum are representatives of the dinoflagellate genus that regularly proliferate on the French coasts and other global coastlines. These harmful species may threaten shellfish harvest and human health due to their ability to synthesize neurotoxic alkaloids of the saxitoxin group. However, some dinoflagellates such as A. minutum, and as reported here A. pacificum as well, may also have a beneficial impact on the environment by producing dimethylsulfoniopropionate-DMSP, the precursor of dimethylsulfur-DMS and sulfate aerosols involved in climate balance. However, environmental conditions might influence Alexandrium physiology towards the production of harmful or environmentally friendly compounds. After assessing the influence of two salinity regimes (33 and 38) relative to each species origin (Atlantic French coast and Mediterranean Lagoon respectively), it appears that DMSP and toxin content was variable between the three experimented strains and that higher salinity disadvantages toxin production and tends to favor the production of the osmolytes DMSP and glycine betaine. Hence, this key metabolite production is strain and species-dependent and is influenced by environmental conditions of salinity which in turn, can diversely affect the environment. Widespread coastal blooms of A. minutum and A. pacificum, although being a risk for seafood contamination with toxins, are also a DMSP and DMS source that potentially contribute to the ecosystem structuration and climate. Regarding recent advances in DMSP biosynthesis pathway, 3 dsyB homologs were found in A. minutum but no homolog of the diatom sequence TpMMT.
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Editeur Lieu de Publication Éditeur
Langue English Langue du Résumé Titre Original
Éditeur de collection Titre de collection Titre de collection Abrégé
Volume de collection Numéro de collection Edition
ISSN 0141-1136 ISBN Médium
Région Expédition Conférence
Notes WOS:000571185300020 Approuvé pas de
Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2903
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Auteur Delcourt, N.; Lagrange, E.; Abadie, E.; Fessard, V.; Fremy, J.-M.; Vernoux, J.-P.; Peyrat, M.-B.; Maignien, T.; Arnich, N.; Molgo, J.; Mattei, C.
Titre Pinnatoxins' Deleterious Effects on Cholinergic Networks: From Experimental Models to Human Health Type Article scientifique
Année 2019 Publication Revue Abrégée Mar. Drugs
Volume 17 Numéro 7 Pages 425
Mots-Clés acute neurotoxicity; block; cyclic imines; dinoflagellate; human intoxication; myasthenia gravis; myasthenia-gravis; neuromuscular-transmission; nicotinic acetylcholine receptors; nicotinic acetylcholine-receptors; pinnatoxins; rat diaphragm; toxicity; toxins; Vulcanodinium rugosum; vulcanodinium-rugosum
Résumé Pinnatoxins (PnTXs) are emerging neurotoxins that were discovered about 30 years ago. They are solely produced by the marine dinoflagellate Vulcanodinium rugosum, and may be transferred into the food chain, as they have been found in various marine invertebrates, including bivalves. No human intoxication has been reported to date although acute toxicity was induced by PnTxs in rodents. LD50 values have been estimated for the different PnTXs through the oral route. At sublethal doses, all symptoms are reversible, and no neurological sequelae are visible. These symptoms are consistent with impairment of central and peripheral cholinergic network functions. In fact, PnTXs are high-affinity competitive antagonists of nicotinic acetylcholine receptors (nAChRs). Moreover, their lethal effects are consistent with the inhibition of muscle nAChRs, inducing respiratory distress and paralysis. Human intoxication by ingestion of PnTXs could result in various symptoms observed in episodes of poisoning with natural nAChR antagonists. This review updates the available data on PnTX toxicity with a focus on their mode of action on cholinergic networks and suggests the effects that could be extrapolated on human physiology.
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Editeur Lieu de Publication Éditeur
Langue English Langue du Résumé Titre Original
Éditeur de collection Titre de collection Titre de collection Abrégé
Volume de collection Numéro de collection Edition
ISSN 1660-3397 ISBN Médium
Région Expédition Conférence
Notes WOS:000478650600036 Approuvé pas de
Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2622
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