title: Cellular and transcriptional responses of Crassostrea gigas hemocytes exposed in vitro to brevetoxin (PbTx-2).
abstract: Hemocytes mediate a series of immune reactions essential for bivalve survival in the environment, however, the impact of harmful algal species and their associated phycotoxins upon bivalve immune system is under debate. To better understand the possible toxic effects of these toxins, Crassostrea gigas hemocytes were exposed to brevetoxin (PbTx-2). Hemocyte viability, monitored through the neutral red retention and MTT reduction assays, and apoptosis (Hoechst staining) remained unchanged during 12 h of exposure to PbTx-2 in concentrations up to 1000 µg/L. Despite cell viability and apoptosis remained stable, hemocytes incubated for 4 h with 1000 µg/L of PbTx-2 revealed higher expression levels of Hsp70 (p < 0.01) and CYP356A1 (p < 0.05) transcripts and a tendency to increase FABP expression, as evaluated by Real-Time quantitative PCR. The expression of other studied genes (BPI, IL-17, GSTO, EcSOD, Prx6, SOD and GPx) remained unchanged. The results suggest that the absence of cytotoxic effects of PbTx-2 in Crassostrea gigas hemocytes, even at high concentrations, allow early defense responses to be produced by activating protective mechanisms associated to detoxification (CYP356A1 and possibly FABP) and stress (Hsp70), but not to immune or to antioxidant (BPI, IL-17, EcSOD, Prx6, GPx and SOD) related genes.
authors.affiliation: Laboratory of Immunology Applied to Aquaculture, Department of Cell Biology, Embryology and Genetics, Biological Sciences Center, Federal University of Santa Catarina, 88040-900, Florianópolis, SC, Brazil.|Laboratory of Cell Defense, Department of Biochemistry, Biological Sciences Center, Federal University of Santa Catarina, 88040-900, Florianópolis, SC, Brazil.
authors.forename: Danielle F
authors.initials: DF
authors.lastname: Mello
authors.affiliation: Laboratory of Immunology Applied to Aquaculture, Department of Cell Biology, Embryology and Genetics, Biological Sciences Center, Federal University of Santa Catarina, 88040-900, Florianópolis, SC, Brazil.
authors.forename: Eliza S
authors.initials: ES
authors.lastname: De Oliveira
authors.affiliation: Laboratory of Immunology Applied to Aquaculture, Department of Cell Biology, Embryology and Genetics, Biological Sciences Center, Federal University of Santa Catarina, 88040-900, Florianópolis, SC, Brazil.
authors.forename: Renato C
authors.initials: RC
authors.lastname: Vieira
authors.affiliation: Laboratory of Immunology Applied to Aquaculture, Department of Cell Biology, Embryology and Genetics, Biological Sciences Center, Federal University of Santa Catarina, 88040-900, Florianópolis, SC, Brazil.
authors.forename: Erik
authors.initials: E
authors.lastname: Simoes
authors.affiliation: Laboratory of Cell Defense, Department of Biochemistry, Biological Sciences Center, Federal University of Santa Catarina, 88040-900, Florianópolis, SC, Brazil.
authors.forename: Rafael
authors.initials: R
authors.lastname: Trevisan
authors.affiliation: Laboratory of Cell Defense, Department of Biochemistry, Biological Sciences Center, Federal University of Santa Catarina, 88040-900, Florianópolis, SC, Brazil.
authors.forename: Alcir Luiz
authors.initials: AL
authors.lastname: Dafre
authors.affiliation: Laboratory of Immunology Applied to Aquaculture, Department of Cell Biology, Embryology and Genetics, Biological Sciences Center, Federal University of Santa Catarina, 88040-900, Florianópolis, SC, Brazil.
authors.forename: Margherita Anna
authors.initials: MA
authors.lastname: Barracco
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D017209:Apoptosis / Q000187:drug effects; D002469:Cell Separation; D002470:Cell Survival / Q000187:drug effects; D004396:Coloring Agents; D049896:Crassostrea / Q000502:physiology*; D018076:DNA, Complementary / Q000096:biosynthesis; D006434:Hemocytes / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D006458:Hemolymph / Q000166:cytology; D008658:Inactivation, Metabolic; D008387:Marine Toxins / Q000494:pharmacology*; D009499:Neutral Red; D035964:Oxocins / Q000494:pharmacology*; D012313:RNA / Q000096:biosynthesis; D060888:Real-Time Polymerase Chain Reaction; D013312:Stress, Physiological / Q000235:genetics; D013778:Tetrazolium Salts; D013844:Thiazoles; D014158:Transcription, Genetic / Q000187:drug effects*
chemical_list: D000975:Antioxidants; D004396:Coloring Agents; D018076:DNA, Complementary; D008387:Marine Toxins; D035964:Oxocins; C051732:Ptychodiscus brevis T2 toxin; D013778:Tetrazolium Salts; D013844:Thiazoles; D009499:Neutral Red; D012313:RNA; C022616:thiazolyl blue