title: Ovatoxin-a, A Palytoxin Analogue Isolated from Ostreopsis cf. ovata Fukuyo: Cytotoxic Activity and ELISA Detection.
abstract: This study provides the first evaluation of the cytotoxic effects of the recently identified palytoxin (PLTX) analog, ovatoxin-a (OVTX-a), the major toxin produced by Ostreopsis cf. ovata in the Mediterranean Sea. Its increasing detection during Ostreopsis blooms and in seafood highlights the need to characterize its toxic effects and to set up appropriate detection methods. OVTX-a is about 100 fold less potent than PLTX in reducing HaCaT cells viability (EC50 = 1.1 × 10(-9) M vs 1.8 × 10(-11) M, MTT test) in agreement with a reduced binding affinity (Kd = 1.2 × 10(-9) vs 2.7 × 10(-11) M, saturation experiments on intact cells). Similarly, OVTX-a hemolytic effect is lower than that of the reference PLTX compound. Ost-D shows the lowest cytotoxicity toward HaCaT keratinocytes, suggesting the lack of a hydroxyl group at C44 as a critical feature for PLTXs cytotoxic effects. A sandwich ELISA developed for PLTX detects also OVTX-a in a sensitive (LOD = 4.2 and LOQ = 5.6 ng/mL) and accurate manner (Bias = 0.3%), also in O. cf. ovata extracts and contaminated mussels. Although in vitro OVTX-a appears less toxic than PLTX, its cytotoxicity at nanomolar concentrations after short exposure time rises some concern for human health. The sandwich ELISA can be a viable screening method for OVTXs detection in monitoring program.
authors.affiliation: Department of Life Science, University of Trieste , 34127 Trieste, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Pelin
authors.affiliation: Department of Pharmacy, University of Napoli Federico II , 80131 Napoli, Italy.
authors.forename: Martino
authors.initials: M
authors.lastname: Forino
authors.affiliation: Department of Life Science, University of Trieste , 34127 Trieste, Italy.
authors.forename: Valentina
authors.initials: V
authors.lastname: Brovedani
authors.affiliation: Department of Pharmacy, University of Napoli Federico II , 80131 Napoli, Italy.
authors.forename: Luciana
authors.initials: L
authors.lastname: Tartaglione
authors.affiliation: Department of Pharmacy, University of Napoli Federico II , 80131 Napoli, Italy.
authors.forename: Carmela
authors.initials: C
authors.lastname: Dell'Aversano
authors.affiliation: Interdepartmental Center for Research in Environmental Sciences, University of Bologna , 481230 Ravenna, Italy.
authors.forename: Rossella
authors.initials: R
authors.lastname: Pistocchi
authors.affiliation: U.S. Army Medical Research Institute of Infectious Diseases, Ft. Detrick, Maryland, 21701-5011 United States.
authors.forename: Mark
authors.initials: M
authors.lastname: Poli
authors.affiliation: Department of Life Science, University of Trieste , 34127 Trieste, Italy.
authors.forename: Silvio
authors.initials: S
authors.lastname: Sosa
authors.affiliation: Department of Life Science, University of Trieste , 34127 Trieste, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: Florio
authors.affiliation: Department of Pharmacy, University of Napoli Federico II , 80131 Napoli, Italy.
authors.forename: Patrizia
authors.initials: P
authors.lastname: Ciminiello
authors.affiliation: Department of Life Science, University of Trieste , 34127 Trieste, Italy.
authors.forename: Aurelia
authors.initials: A
authors.lastname: Tubaro
mesh_terms: D000178:Acrylamides; D000818:Animals; D049872:Bivalvia / Q000737:chemistry; D002460:Cell Line; D003064:Cnidarian Venoms; D004141:Dinoflagellida / Q000737:chemistry*; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D008387:Marine Toxins / Q000302:isolation & purification / Q000633:toxicity*; D008522:Mediterranean Sea; D017747:Seafood; D012758:Shellfish; D018675:Toxicity Tests; D000095702:Polyether Toxins
chemical_list: D000178:Acrylamides; D003064:Cnidarian Venoms; D008387:Marine Toxins; C573585:ovatoxin-a; C010272:palytoxin; D000095702:Polyether Toxins