CYTOTOXICITY OF VENOM FROM HETEROTRICHOUS MICROBASIC EURYTELE NEMATOCYSTS OF PELAGIA NOCTILUCA (CNIDARIA: SCYPHOZOA) TO L929 MOUSE LUNG FIBROBLASTS. PRELIMINARY RESULTS.

During last decades many studies highlighted cnidarian relevance in worldwide trophic chains, as well as the considerable frequency and size of outbreaks over the years. A high inter-specific variability, survival ability and harsh conditions resistance built a clear path for these animals to the top of trophic chains, with a corresponding raising impact on sea-related anthropogenic activities. Indeed, cnidarians possess efficient stinging characteristics and represent a threat to bathers and fishermen. Pelagia noctiluca (Forsskål, 1775), the “Mauve Stinger”, is a common Mediterranean scyphozoan jellyfish. It occurs mainly from March to May, but also throughout the year in South Tyrrhenian waters around Northeastern Sicily. The venomousness of this jellyfish is due to three main different kinds of nematocysts, which are known to contain toxins which at present are not exhaustively known. In this study, a first evaluation of the cytotoxic activity of heterotrichous microbasic eurytele nematocysts from Pelagia noctiluca is presented and discussed. Nematocysts were isolated from tentacles of Pelagia noctiluca and the content was extracted by sonication (aqueous extract). Cytotoxicity assays employing MTT assay and Trypan Blue dye exclusion were carried out on L929 mouse lung fibroblasts. Aqueous extracts induced cytotoxicity to L929 cells with 36.9% cell survival after 24 hours treatment with aqueous extract of 150×103 P.noctiluca nematocysts/ml, and 68.9% cell survival after treatment with extract of 75×103 nematocysts/ml. Further analysis, including the evaluation of the oxidative stress and considering cellular targets such as apoptotic ways, antioxidant enzymes, ion channel inhibition, ROS production, and cellular signals correlated to protein expression could be further research developments and are thought to be required in order to understand the suitability of extracts from Pelagia noctiluca nematocysts as valuables biopharmaceutical substances. Acknowledgements: The authors wish to thank Dr. Guido Bonello (DISTAV, University of Genova) for his help in the experimental phase of this work.