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Thomas K Doyle - One of the best experts on this subject based on the ideXlab platform.
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Fisheries bycatch data provide insights into the distribution of the mauve stinger (Pelagia Noctiluca) around Ireland
ICES Journal of Marine Science, 2010Co-Authors: Thomas Bastian, John Davenport, Graeme C Hays, D. Stokes, Jane E. Kelleher, Thomas K DoyleAbstract:Noctiluca, over an area .160 000 km 2 around Ireland and the UK in 2009. The species accounted for 93% of the overall catch of gelatinous organisms, with an average catch biomass of 0.26+ 2.3 kg ha 21 . The study area was divided into four subregions (North, West, Southwest, and South), and the distribution and abundance of P. Noctiluca displayed both inter- and intraregional variations. Individual bell diameters ranged from 1 to 13.5 cm (median 4.5 cm, s.d. 1.2 cm), and the size distribution also varied spatially. It is the first time that such detailed information has been made available for P. Noctiluca in a part of the Northeast Atlantic where its impact on the salmon aquaculture industry can be considerable. Finally, the possibility of using annual datasets from this type of fisheries survey to develop time-series that, in the future, will allow investigation of relationships between long-term variations of P. Noctiluca populations and climatic factors in the area is addressed.
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widespread occurrence of the jellyfish pelagia Noctiluca in irish coastal and shelf waters
Journal of Plankton Research, 2008Co-Authors: Thomas K Doyle, Henk De Haas, Don Cotton, Boris Dorschel, Valerie Cummins, Jonathan D R Houghton, John Davenport, Graeme C HaysAbstract:An oceanic cruise (October 2007) revealed the widespread occurrence of Pelagia Noctiluca in the NE Atlantic just prior to a major fish kill induced by P. Noctiluca in Irish coastal waters.
Iain M. Suthers - One of the best experts on this subject based on the ideXlab platform.
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The influence of upwelling, coastal currents and water temperature on the distribution of the red tide dinoflagellate, Noctiluca scintillans , along the east coast of Australia
Hydrobiologia, 2007Co-Authors: Jocelyn Dela-cruz, Jason H. Middleton, Iain M. SuthersAbstract:Quasi-synoptic surveys along the east coast of Australia between 28 and 34°S show that the heterotrophic dinoflagellate, Noctiluca scintillans, occurs along this entire stretch of the coast. Areas of relatively high abundance of Noctiluca were observed downstream of regions predisposed to current-induced upwellings as a consequence of alongshore topographic variations. High-resolution temporal and spatial sampling of upwelling events showed that Noctiluca was abundant (up to 28 cells l−1) within mature upwelled waters. A high proportion (>80%) of fed Noctiluca cells (cells with prey in their vacuoles) was observed in the mature upwelled waters indicating that the observed increase in abundance of Noctiluca was associated with increased feeding activity. The absolute abundance of Noctiluca in upwelled waters was, however, found to vary from one upwelling location to another and between seasons. In particular, highest abundances of Noctiluca were recorded south of 31.5°S, where the East Australian Current (EAC) characteristically separates from the coast. The high abundances partly arise from southward advection and retention of the Noctiluca cells, and partly from upwelling inshore of the separated EAC driven by cross-shelf boundary layer fluxes. The temperature of the EAC was also found to influence absolute abundances. Surface water temperatures during our summer cruise were anomalously high due to a strong La Nina phase, and up to 4°C warmer than during our spring cruise. We found that the warmer surface water temperatures were associated with relatively lower average abundances of Noctiluca in the near shore zone.
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Population growth and transport of the red tide dinoflagellate, Noctiluca scintillans, in the coastal waters off Sydney Australia, using cell diameter as a tracer
Limnology and Oceanography, 2003Co-Authors: Jocelyn Dela-cruz, Jason H. Middleton, Iain M. SuthersAbstract:Spatial abundance patterns of the heterotrophic dinoflagellate, Noctiluca scintillans, were investigated along the southeast coast of Australia to address the hypothesis that population growth of Noctiluca is driven by anthropogenic eutrophication. Abundance patterns were related to the immediate physical flow field and not the conditions conducive to growth. Noctiluca cells were advected southward with the East Australian Current, which was the dominant transport vector for the cells in this region. Areas of population growth of Noctiluca were identified by variations in cell-size distributions. Small cells ( ,525 mm) were considered to be capable of population growth, in contrast to red tide cells, which are known to be large (.600 mm), senescent, and the end result of a long series of biological and physical processes occurring in temporally and spatially distant water masses. Small cells were therefore considered to be located closer to the region in which growth was stimulated. The proportion of small cells in the samples was significantly correlated with relatively high concentrations of chlorophyll a. Consequently, this relationship was used to show that population growth of Noctiluca may be stimulated by an increase in chlorophyll a due to sewage discharge, although the prevailing hydrological conditions determine the likelihood of such impacts. High chlorophyll a concentrations within estuaries were also found to sustain a stable but low standing stock of Noctiluca, which may seed oceanic stocks. Thus, by examining cell size rather than abundance distributions, we identified and interpreted the variance in the spatial abundance patterns of Noctiluca within a dynamic hydrological environment.
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Temporal abundance patterns of the red tide dinoflagellate Noctiluca scintillans along the southeast coast of Australia
Marine Ecology Progress Series, 2002Co-Authors: Jocelyn Dela-cruz, Penelope Ajani, Randall Lee, T. R. Pritchard, Iain M. SuthersAbstract:Noctiluca scintillans was seasonally abundant during the austral spring and summer with typical values of 16 cells l -1 , but depleted in autumn and winter, with values of 80%) of Noctiluca cells contained food particles in their vacuoles during the diatom blooms, suggesting that the increase in abundance of Noctiluca was most likely stimulated by food availability. Pulses of small-sized Noctiluca cells dur- ing the diatoms blooms were indicative of this population growth. The δ 15 N isotopic similarity of the red tide cells collected from spatially and temporally distant water masses suggests that the prey of Noctiluca were derived from a single nutrient source, most likely uplifted slope water. This study shows that the predominant underlying mechanism regulating population growth of Noctiluca along the southeast coast of Australia is the uplifting of nutrient-rich slope water. The uplifting events stimulate phytoplankton blooms which in turn stimulate Noctiluca blooms.
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Population ecology of Noctiluca scintillans Macartney, a red-tide-forming dinoflagellate
Marine and Freshwater Research, 1999Co-Authors: Shauna A. Murray, Iain M. SuthersAbstract:The population ecology of the large heterotrophic dinoflagellate Noctiluca scintillans Macartney was examined in the coastal ocean and two estuaries in south-eastern Australia from July 1996 to June 1997. High concentrations (>100 cells L n1 ) occurred in spring and again in late summer, and low concentrations ( 10 4 cells L n1 ), and were characterized by large diameters (400n1200 mm), cell lysis and uniformly low nutritional status; at this time, Noctiluca cells from estuaries were generally fewer, smaller and in better condition. Overall, cell concentrations were higher in coastal waters than in the estuaries, and red tides of Noctiluca probably developed along the local coast (in spring) or were advected into the area from northern regions (in late summer). Extra keywords: heterotrophic dinoflagellate, blooms, seasonality, cell condition
Josep Maria Gili - One of the best experts on this subject based on the ideXlab platform.
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Pathways for Pelagia Noctiluca jellyfish intrusions onto the Catalan shelf and their interactions with early life fish stages
Journal of Marine Systems, 2018Co-Authors: Ana Sabatés, Jennifer E. Purcell, Josep Maria Gili, Jordi Salat, Uxue Tilves, Vanesa Raya, Maria J. Pascual, Veronica FuentesAbstract:Abstract This study investigates the possible pathways for Pelagia Noctiluca intrusions over the shelf to understand the interactions between jellyfish and fish larvae. To assess how the presence of P. Noctiluca may influence populations of Engraulis encrasicolus and Trachurus trachurus, we analyzed the effect of environmental conditions on the abundance and spatial distribution of P. Noctiluca, medusae and ephyrae, and early life stages of these two fish species along the Catalan coast. The highest concentrations of P. Noctiluca were found offshore, all along the Northern Current path. Their occurrence over the shelf was associated with intrusions of open sea waters that contoured anticyclonic eddies generated by the oscillatory behaviour of the current. Anchovy larvae were found widely over the shelf, but were especially abundant in the north and in waters influenced by the Ebro river. Spatial patterns of anchovy larvae were defined better by physical environmental factors than by the presence of P. Noctiluca, whose distribution clearly was determined by the circulation. The differences in environmental conditions controlling the populations of P. Noctiluca and E. encrasicolus larvae prevent their general coexistence over the shelf and prey-predator interactions remained limited to the areas affected by offshore intrusions. It is remarkable that the occurrence of T. trachurus larvae and juveniles was limited to locations over the shelf where jellyfish were observed and never offshore. This suggests that the association between fish and jellyfish occur once jellyfish have been advected from offshore towards the shelf, favouring the survival of larvae and juveniles of T. trachurus.
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Pelagia Noctiluca in the Mediterranean Sea
Jellyfish Blooms, 2013Co-Authors: Antonio Canepa, Ana Sabatés, Veronica Fuentes, Stefano Piraino, Ferdinando Boero, Josep Maria GiliAbstract:Over recent decades, man’s expanding influence on the oceans has begun to cause change in some regions, including in the Mediterranean Sea. New proliferations of jellyfish may be occurring in the Mediterranean Sea, possibly in response to the cumulative effects of some of these anthropogenic impacts. In the Mediterranean Sea, many of these “proliferation events” are due to Pelagia Noctiluca, an oceanic scyphozoan that has become very abundant along the coasts. Pelagia Noctiluca is usually considered to be the most important jellyfish species in the Mediterranean Sea due to its widespread distribution, abundance, and ecological role and also because of its negative interaction with humans. Climatic conditions that favor enhanced reproduction by P. Noctiluca and probably also determine optimal conditions for the formation of blooms are characterized by mild winters, low rainfall, high temperature, and high-atmospheric pressure. The Medusa Project in Catalonia aims to understand the spatiotemporal dynamics of the jellyfish populations in the NW Mediterranean Sea by undertaking daily sampling during summer (May to September) of 243 beaches, covering more than 500 km of coast. Data on beach strandings along the Spanish Catalan coast revealed that jellyfish occur in greatest concentrations along the northern Catalan coast and on beaches located close to marine canyons. The arrival of P. Noctiluca to the coast depends firstly on the offshore production of jellyfish. Oceanographic structures like fronts, which enhance and maintain high levels of biological production and provide ideal conditions for feeding, growth, and reproduction of the jellyfish are present in the NW Mediterranean. The weakening of the front results in large numbers of P. Noctiluca being driven into the coast by southeast winds. In the NW Mediterranean Sea P. Noctiluca exert top-down control over a variety of prey including fish eggs and possibly the invasive ctenophore Mnemiopsis leidyi. P. Noctiluca is also responsible for the majority of the stings incurred by bathers along the Catalan coast. Finally, we recommend that similar sampling programs should be done elsewhere to better understand changes in the distribution, abundance, and blooming patterns of dangerous jellyfish species.
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Planktonic cnidarian distribution and feeding of Pelagia Noctiluca in the NW Mediterranean Sea
Hydrobiologia, 2010Co-Authors: Ana Sabatés, Francesc Pagès, Dacha Atienza, Veronica Fuentes, Jennifer E. Purcell, Josep Maria GiliAbstract:Pelagic cnidarians are important consumers of zooplankton and ichthyoplankton in the world’s oceans, and thus harm fisheries as competitors and predators of fish. This study examined the inshore-offshore distribution of pelagic cnidarians and the trophic ecology of Pelagia Noctiluca ephyrae ( 12 mm) the number of prey increased with medusa size rather than the size of the larvae. The temporal and spatial co-occurrence of P. Noctiluca with early life stages of fish suggests that P. Noctiluca may be an important predator on summer ichthyoplankton.
Veronica Fuentes - One of the best experts on this subject based on the ideXlab platform.
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Pathways for Pelagia Noctiluca jellyfish intrusions onto the Catalan shelf and their interactions with early life fish stages
Journal of Marine Systems, 2018Co-Authors: Ana Sabatés, Jennifer E. Purcell, Josep Maria Gili, Jordi Salat, Uxue Tilves, Vanesa Raya, Maria J. Pascual, Veronica FuentesAbstract:Abstract This study investigates the possible pathways for Pelagia Noctiluca intrusions over the shelf to understand the interactions between jellyfish and fish larvae. To assess how the presence of P. Noctiluca may influence populations of Engraulis encrasicolus and Trachurus trachurus, we analyzed the effect of environmental conditions on the abundance and spatial distribution of P. Noctiluca, medusae and ephyrae, and early life stages of these two fish species along the Catalan coast. The highest concentrations of P. Noctiluca were found offshore, all along the Northern Current path. Their occurrence over the shelf was associated with intrusions of open sea waters that contoured anticyclonic eddies generated by the oscillatory behaviour of the current. Anchovy larvae were found widely over the shelf, but were especially abundant in the north and in waters influenced by the Ebro river. Spatial patterns of anchovy larvae were defined better by physical environmental factors than by the presence of P. Noctiluca, whose distribution clearly was determined by the circulation. The differences in environmental conditions controlling the populations of P. Noctiluca and E. encrasicolus larvae prevent their general coexistence over the shelf and prey-predator interactions remained limited to the areas affected by offshore intrusions. It is remarkable that the occurrence of T. trachurus larvae and juveniles was limited to locations over the shelf where jellyfish were observed and never offshore. This suggests that the association between fish and jellyfish occur once jellyfish have been advected from offshore towards the shelf, favouring the survival of larvae and juveniles of T. trachurus.
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Reproductive and bloom patterns of Pelagia Noctiluca in the Strait of Messina, Italy
Estuarine Coastal and Shelf Science, 2018Co-Authors: Giacomo Milisenda, Veronica Fuentes, Ferdinando Boero, A. Martinez-quintana, M. Bosch-belmar, G. Aglieri, Stefano PirainoAbstract:Abstract Investigations on sexual reproduction of jellyfish are essential to understanding mechanisms and patterns of outbreaks formation. Pelagia Noctiluca (Forskal, 1775) (Scyphozoa) is known as the predominant jellyfish species with direct development in Western and Central Mediterranean Sea. In this paper we used integrated morphometric, histological, and biochemical approaches to investigate the annual reproductive biology of P. Noctiluca from the Strait of Messina (South Thyrrenian Sea), a key proliferation area for this species due to favourable temperatures and high productivity. From November 2011 to September 2012, P. Noctiluca sexual reproduction occurred throughout the year, with two seasonal peaks (autumn, spring) of spawning and embryonic development. Gonads of female P. Noctiluca were characterized by a large amount of mature eggs of small size (diameter 200 μm) were detected during low availability of prey. Two morphometric indexes were applied: the Gonad-Somatic Index (GSI, gonadal/somatic tissue dry weight ratio) and Fecundity Index (FI, n° eggs mm −2 * gonadal dry weight). The FI showed longer spawning periods than the GSI, providing a better causal-mechanistic explanation for the year-round occurrence of P. Noctiluca in the Strait of Messina. Protein contents of the gonads changed seasonally, with the highest concentrations during the pre-spawning periods. We suggest that investigations on jellyfish sexual reproduction can provide biological information relevant for understanding mechanisms of jellyfish blooms as well as for the management of coastal zones affected by outbreaks of gelatinous species.
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Pelagia Noctiluca in the Mediterranean Sea
Jellyfish Blooms, 2013Co-Authors: Antonio Canepa, Ana Sabatés, Veronica Fuentes, Stefano Piraino, Ferdinando Boero, Josep Maria GiliAbstract:Over recent decades, man’s expanding influence on the oceans has begun to cause change in some regions, including in the Mediterranean Sea. New proliferations of jellyfish may be occurring in the Mediterranean Sea, possibly in response to the cumulative effects of some of these anthropogenic impacts. In the Mediterranean Sea, many of these “proliferation events” are due to Pelagia Noctiluca, an oceanic scyphozoan that has become very abundant along the coasts. Pelagia Noctiluca is usually considered to be the most important jellyfish species in the Mediterranean Sea due to its widespread distribution, abundance, and ecological role and also because of its negative interaction with humans. Climatic conditions that favor enhanced reproduction by P. Noctiluca and probably also determine optimal conditions for the formation of blooms are characterized by mild winters, low rainfall, high temperature, and high-atmospheric pressure. The Medusa Project in Catalonia aims to understand the spatiotemporal dynamics of the jellyfish populations in the NW Mediterranean Sea by undertaking daily sampling during summer (May to September) of 243 beaches, covering more than 500 km of coast. Data on beach strandings along the Spanish Catalan coast revealed that jellyfish occur in greatest concentrations along the northern Catalan coast and on beaches located close to marine canyons. The arrival of P. Noctiluca to the coast depends firstly on the offshore production of jellyfish. Oceanographic structures like fronts, which enhance and maintain high levels of biological production and provide ideal conditions for feeding, growth, and reproduction of the jellyfish are present in the NW Mediterranean. The weakening of the front results in large numbers of P. Noctiluca being driven into the coast by southeast winds. In the NW Mediterranean Sea P. Noctiluca exert top-down control over a variety of prey including fish eggs and possibly the invasive ctenophore Mnemiopsis leidyi. P. Noctiluca is also responsible for the majority of the stings incurred by bathers along the Catalan coast. Finally, we recommend that similar sampling programs should be done elsewhere to better understand changes in the distribution, abundance, and blooming patterns of dangerous jellyfish species.
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Planktonic cnidarian distribution and feeding of Pelagia Noctiluca in the NW Mediterranean Sea
Hydrobiologia, 2010Co-Authors: Ana Sabatés, Francesc Pagès, Dacha Atienza, Veronica Fuentes, Jennifer E. Purcell, Josep Maria GiliAbstract:Pelagic cnidarians are important consumers of zooplankton and ichthyoplankton in the world’s oceans, and thus harm fisheries as competitors and predators of fish. This study examined the inshore-offshore distribution of pelagic cnidarians and the trophic ecology of Pelagia Noctiluca ephyrae ( 12 mm) the number of prey increased with medusa size rather than the size of the larvae. The temporal and spatial co-occurrence of P. Noctiluca with early life stages of fish suggests that P. Noctiluca may be an important predator on summer ichthyoplankton.
Hassen Bacha - One of the best experts on this subject based on the ideXlab platform.
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Evaluation of anti-proliferative and anti-inflammatory activities of Pelagia Noctiluca venom in Lipopolysaccharide/Interferon-γ stimulated RAW264.7 macrophages
Biomedicine and Pharmacotherapy, 2016Co-Authors: Yosra Ayed, Rabiaa Manel Sghaier, Dhafer Laouini, Hassen BachaAbstract:Components of Pelagia Noctiluca (P. Noctiluca) venom were evaluated for their anticancer and nitric Oxide (NO) inhibition activities. Three fractions, out of four, obtained by gel filtration on Sephadex G75 of P. Noctiluca venom revealed an important selective anti-proliferative activity on several cell lines such as human bladder carcinoma (RT112), human glioblastoma (U87), and human myelogenous leukemia (K562) but not on mitogen-stimulated peripheral blood mononuclear cells. Interestingly, P. Noctiluca components showed an important dose-dependent anti-inflammatory activity, through inhibition of NO production via transcriptional regulation of Inducible NO Synthase (iNOS), in IFN-γ/LPS stimulated RAW 264.7 macrophages. These data strongly suggest that P. Noctiluca venom could be used as a natural inhibitor of cancer cell lines and a potent anti-inflammatory agent for the treatment of anti-inflammatory diseases.
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evaluation of anti proliferative and anti inflammatory activities of pelagia Noctiluca venom in lipopolysaccharide interferon γ stimulated raw264 7 macrophages
Biomedicine & Pharmacotherapy, 2016Co-Authors: Yosra Ayed, Rabiaa Manel Sghaier, Dhafer Laouini, Hassen BachaAbstract:Components of Pelagia Noctiluca (P. Noctiluca) venom were evaluated for their anticancer and nitric Oxide (NO) inhibition activities. Three fractions, out of four, obtained by gel filtration on Sephadex G75 of P. Noctiluca venom revealed an important selective anti-proliferative activity on several cell lines such as human bladder carcinoma (RT112), human glioblastoma (U87), and human myelogenous leukemia (K562) but not on mitogen-stimulated peripheral blood mononuclear cells. Interestingly, P. Noctiluca components showed an important dose-dependent anti-inflammatory activity, through inhibition of NO production via transcriptional regulation of Inducible NO Synthase (iNOS), in IFN-γ/LPS stimulated RAW 264.7 macrophages. These data strongly suggest that P. Noctiluca venom could be used as a natural inhibitor of cancer cell lines and a potent anti-inflammatory agent for the treatment of anti-inflammatory diseases.
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Impairment of the cell-to-matrix adhesion and cytotoxicity induced by the Mediterranean jellyfish Pelagia Noctiluca venom and its fractions in cultured glioblastoma cells
Lipids in Health and Disease, 2012Co-Authors: Yosra Ayed, Manel Bousabbeh, Hazem Ben Mabrouk, Maram Morjen, Naziha Marrakchi, Hassen BachaAbstract:Background: The biodiversity of the marine environment and the associated chemical diversity constitute a practically unlimited source of new active substances in the field of the development of bioactive products. In our study, we have investigated the efficiency of the venom from the Mediterranean jellyfish, Pelagia Noctiluca and its fractions for anti-proliferative and anti-cell adhesion to cell-extracellular matrix activities. Results: Our experiments have indicated that the separation of the Mediterranean jellyfish Pelagia Noctiluca crude venom extract by sephadex G-75 chromatography led to four fractions (F1, F2, F3, and F4). Among the four fractions F1 and F3 were cytotoxic against U87 cells with IC50 values of 125 and 179 mu g/ml respectively. The venom, F1, F2 and F 3 showed significant anti-proliferative activity in time-dependent manner. Our results also suggest that these fractions and the venom are able to inhibit cell adhesion to fibrinogen in dose-dependent manner. This inhibition is reliant on its ability to interact with integrins. Conclusions: To conclude, we have demonstrated for the first time that Pelagia Noctiluca venom and its fractions especially (F1 and F2) display potent anti-tumoral properties. Separation by sephadex G-75 chromatography give rise to more active fractions than the crude venom extract. The purification and the determination of chemical structures of compounds of these active fractions are under investigation. Overall, Pelagia Noctiluca venom may has the potential to serve as a template for future anticancer-drug development.
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Cell death in relation to DNA damage after exposure to the jellyfish Pelagia Noctiluca nematocysts.
Environmental toxicology, 2012Co-Authors: Yosra Ayed, Chayma Bouaziz, Dalel Brahmi, Chiraz Zaid, Salwa Abid, Hassen BachaAbstract:Studies on the toxicity of Mediterranean jellyfish have gained attention owing to their weak toxic properties. Our research has been mainly performed on the Scyphomedusae. Pelagia Noctiluca is a scyphozoan jellyfish which causes a danger to sea bathers and fishery damages in the Mediterranean Sea. To check whether the cytotoxicity of Pelagia Noctiluca nematocysts was associated to DNA lesions, we have looked for DNA fragmentation by means of the Comet and chromosome aberration assays. To specify cell death pathway, we have investigated caspase-3 activation. Our results have shown that nematocysts reduced cell viability and induced DNA fragmentation in a concentration-dependent manner with a maximum effect at 150 000 nematocysts mL(-1). The high percentage of chromosome aberrations also emphasized the genotoxic character of Pelagia Noctiluca nematocysts in Vero cells. This fragmentation was correlated to apoptosis induction which was confirmed by caspase-3 activation. In conclusion, the present report has suggested that Pelagia Noctiluca nematocysts were able to promote apoptosis in Vero cells and therefore may be useful in cancer therapy.
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induction of cytotoxicity of pelagia Noctiluca venom causes reactive oxygen species generation lipid peroxydation induction and dna damage in human colon cancer cells
Lipids in Health and Disease, 2011Co-Authors: Yosra Ayed, Chayma Bouaziz, Salwa Abid, Manel Boussabbeh, Wiem Zakhama, Hassen BachaAbstract:Background The long-lasting and abundant blooming of Pelagia Noctiluca in Tunisian coastal waters compromises both touristic and fishing activities and causes substantial economic losses. Determining their molecular mode of action is, important in order to limit or prevent the subsequent damages. Thus, the aim of the present study was to investigate the propensity of Pelagia Noctiluca venom to cause oxidative damage in HCT 116 cells and its associated genotoxic effects.