Interactive effects of n-TiO2 and 2,3,7,8-TCDD on the marine bivalve Mytilus galloprovincialis

• Published in: Aquatic toxicology 2014-08, Vol.153, p.53-65
• Main Authors: Canesi, Laura, Frenzilli, Giada, Balbi, Teresa, Bernardeschi, Margherita, Ciacci, Caterina, Corsolini, Simonetta, Della Torre, Camilla, Fabbri, Rita, Faleri, Claudia, Focardi, Silvano, Guidi, Patrizia, Kočan, Anton, Marcomini, Antonio, Mariottini, Michela, Nigro, Marco, Pozo-Gallardo, Karla, Rocco, Lucia, Scarcelli, Vittoria, Smerilli, Arianna, Corsi, Ilaria
• Format: Article
• Language: English
• Subjects: Animal, plant and microbial ecology; Animals; Applied ecology; Biological and medical sciences; Biomarker; Biomarkers - analysis; Dioxin; DNA Damage - drug effects; Drug Interactions; Ecotoxicology, biological effects of pollution; Effects of pollution and side effects of pesticides on protozoa and invertebrates; Fundamental and applied biological sciences. Psychology; Gills - drug effects; Hemocytes - drug effects; Invertebrates; Lysosomes - drug effects; Mollusca; Mytilus - drug effects; Mytilus - genetics; Mytilus - metabolism; Mytilus galloprovincialis; Nanoparticles; Nanoparticles - toxicity; Phagocytosis - drug effects; Polychlorinated Dibenzodioxins - metabolism; Polychlorinated Dibenzodioxins - toxicity; Random Amplified Polymorphic DNA Technique; Titanium - toxicity; Titanium dioxide; Water Pollutants, Chemical - metabolism; Water Pollutants, Chemical - toxicity
• ISSN: 0166-445X; 1879-1514
• DOI: 10.1016/j.aquatox.2013.11.002

•In vitro and in vivo interactive effects of n-TiO2 and TCDD are reported in mussel.•Both synergistic and antagonistic effects were observed on a wide range of biomarkers.•Exposure to of n-TiO2increased TCDD accumulation, indicating a Trojan horse effect. Despite the growing concern over the potential biological impact of nanoparticles (NPs) in the aquatic environment, little is known about their interactions with other pollutants. The bivalve Mytilus sp, largely utilized as a sentinel for marine contamination, has been shown to represent a significant target for different types of NP, including n-TiO2, one of the most widespread in use. In this work, the possible interactive effects of n-TiO2 and 2,3,7,8-TCDD, chosen as models of NP and organic contaminant, respectively, were investigated in Mytilus galloprovincialis. In vitro experiments with n-TiO2 and TCDD, alone and in combination, were carried out in different conditions (concentrations and times of exposure), depending on the target (hemocytes, gill cells and biopsies) and the endpoint measured. Mussels were also exposed in vivo to n-TiO2 (100μgL−1) or to TCDD (0.25μgL−1), alone and in combination, for 96h. A wide range of biomarkers, from molecular to tissue level, were measured: lysosomal membrane stability and phagocytosis in hemocytes, ATP-binding cassette efflux transporters in gills (gene transcription and efflux activity), several biomarkers of genotoxicity in gill and digestive cells (DNA damage, random amplified polymorphic DNA-RAPD changes), lysosomal biomarkers and transcription of selected genes in the digestive gland. The results demonstrate that n-TiO2 and TCDD can exert synergistic or antagonistic effects, depending on experimental condition, cell/tissue and type of measured response. Some of these interactions may result from a significant increase in TCDD accumulation in whole mussel organisms in the presence of n-TiO2, indicating a Trojan horse effect. The results represent the most extensive data obtained so far on the sub-lethal effects of NPs and organic contaminants in aquatic organisms. Moreover, these data extend the knowledge on the molecular and cellular targets of NPs in bivalves.