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- Biomarkers in nereis diversicolor (Polychaeta: Nereididae) as management tools for environmental assessment on the southwest Iberian coastPublication . Gomes, Tânia; Gonzalez-Rey, Maria; Rodriguez-Romero, Araceli; Trombini, Chiara; Riba, Immaculada; Blasco, Julian; Bebianno, Maria JoãoThe environmental quality of the southwest Iberian coast was assessed in different areas (Ria Formosa Lagoon, Guadiana Estuary and Cadiz Bay) focusing on metal contamination (Cd, Cu, Ni, Pb and Zn) in Nereis diversicolor whole tissues. In addition, associated toxicological effects were assessed using a multibiomarker approach combining several conventional biomarkers. The set of biomarkers selected included antioxidant enzymes (catalase, superoxide dismutase and glutathione peroxidase), metallothionein and lipid peroxidation. N. diversicolor from the Ria Formosa Lagoon, Guadiana River and Cadiz Bay responded differently to metal contamination with different biomarker responses showing a clear site trend, suggesting different sources and/or magnitudes of contamination. Cadmium was a source of oxidative stress in polychaetes, mainly in Cadiz Bay, with a significant influence on antioxidant enzymes and enhancement of lipid peroxidation. The highest MT concentrations were in the Ria Formosa Lagoon and in the Guadiana River, where there was a direct relationship with high nickel concentrations. Biomarker responses of N. diversicolor are useful tools for environmental quality assessment on the southwest Iberian coast, and more specific metal biomarkers should be included in future assessments.
- A multibiomarker approach in the clam Ruditapes decussatus to assess the impact of pollution in the Ria Formosa lagoon, South Coast of PortugalPublication . Cravo, Alexandra; Pereira, C.; Gomes, Tânia; Cardoso, Cátia; Serafim, M.A.; Almeida, Cheila; Rocha, T.; Lopes, Belisandra; Company, Rui; Medeiros, A.; Norberto, R.; Pereira, R.; Araújo, O.; Bebianno, Maria JoãoThe Ria Formosa lagoon is an ecosystem whose water quality reflects the anthropogenic influence upon the surrounding areas. In this lagoon, the clam Ruditapes decussatus has a great economical importance and has been widely used as a biomonitor. A multibiomarker approach (d-aminolevulinic acid dehy- dratase, metallothionein, lipid peroxidation, acetylcholinesterase, alkali-labile phosphates, DNA damage) was applied to assess the environmental quality of this ecosystem and the accumulation of contaminants and their potential adverse effects on clams. Clams were sampled in different shellfish beds in the period between July 2007 and December 2008 and abiotic parameters (temperature, salinity, pH and dissolved oxygen of seawater and organic matter in the sediment), condition index, metals (Cd, Cu, Zn, Ni, Pb), TBTs and PAHs concentrations were measured in clam tissues. Data was integrated using Principal Component Analyses and biomarker indices: IBR (Integrated Biomarker Response) and HSI (Health Status Index). This multibiomarker approach enabled discrimination of a time and space trend between sites with different degrees of anthropogenic contamination, identifying one of them (site 2) as the most stressful and summer months as the most critical period for clams due to an increase of environmental stress (anthropogenic pressure along with extreme environmental conditions, e.g. temperature, dissolved oxygen, organic matter in the sediments, etc). The selected biomarkers provided an integrated response to assess the environmental quality of the system, proving to be a useful approach when complex mixtures of contaminants occur.
- Effects of nanoparticles exposure in the mussel Mytilus GalloprovincialisPublication . Gomes, Tânia; Bebianno, Maria João da Anunciação FrancoNanotechnology is rapidly developing and attracting attention due to the exploitation of the novel materials at the nanoscale for application within biomedical, cosmetic, electronic, energy production and environmental sectors. Increased production and widespread use of these nanomaterials result in their release into the environment; nevertheless, the knowledge of their behaviour in aquatic systems is scarce. Accordingly, this thesis assessed the effects of two commercially available nanoparticles, copper oxide (CuO NPs) and silver nanoparticles (Ag NPs), using mussels Mytilus galloprovincialis as bioindicators. To understand the uptake, accumulation and effects of these NPs, mussels were exposed to a realistic environmental concentration of 10 !g.L-1 of CuO (31 ± 10 nm) and Ag NPs (<100 nm) for 15 days, comparative to their ionic counterparts. NPs were characterized and biomarkers of oxidative stress, metal exposure, genotoxicity and neurotoxicity evaluated in mussel tissues. To identify pathways of NP exposure and detect new biomarkers, a proteomic approach was undertaken. Oxidative stress is the major NP-induced toxicity, but with distinct modes of action. Gills are more susceptible to oxidative stress while the digestive gland is the preferential site for NPs accumulation. The oxidative (enzymatic activation/inhibition, metallothionein induction and lipid peroxidation), genotoxic (DNA strand breaks) and neurotoxic (acetylcholinesterase inhibition) changes suggest that NPs toxicity is associated with ROS that induced a cascade of pathways (via nucleus and mitochondria) that ultimately lead to apoptosis but by different mechanisms. New biomarkers candidates were identified: caspase 3/7-1, cathepsin-L and zinc-finger protein for CuO NPs and precollagen-P, major vault protein and ras partial for Ag NPs exposure. Overall, these results show that even though oxidative stress and apoptosis are similar outcomes for NP toxicity, particle composition, size, solubility, aggregation and chemistry are key elements for determining their mode of action. This study contributed to understand the CuO and Ag NPs behaviour, bioavailability and toxicity in aquatic systems and their uptake and effects in filter-feeding organisms.
- Proteomic changes in Corbicula fluminea exposed to wastewater from a psychiatric hospitalPublication . Bebianno, Maria João; Sroda, S.; Gomes, Tânia; Chan, P.; Bonnafe, E.; BUDZINSKI, Hélène; Geret, F.The increase use of pharmaceutical compounds in veterinary practice and human population results in the ubiquitous presence of these compounds in aquatic ecosystems. Because pharmaceuticals are highly bioactive, there is concern about their toxicological effects in aquatic organisms. Therefore, the aim of this study was to assess the effects of an effluent from a psychiatric hospital (containing a complex mixture of 25 pharmaceutical compounds from eleven therapeutic classes) on the freshwater clam Corbicula fluminea using a proteomic approach. The exposure of C. fluminea to this complex effluent containing anxiolytics, analgesics, lipid regulators, beta blockers, antidepressants, antiepileptics, antihistamines, antihypertensives, antiplatelets and antiarrhythmics induced protein changes after 1 day of exposure in clam gills and digestive gland more evident in the digestive gland. These changes included increase in the abundance of proteins associated with structural (actin and tubulin), cellular functions (calreticulin, proliferating cell nuclear antigen (PCNA), T complex protein 1 (TCP1)) and metabolism (aldehyde dehydrogenase (ALDH), alcohol dehydrogenase, 6 phosphogluconate dehydrogenase). Results from this study indicate that calreticulin, PCNA, ALDH and alcohol dehydrogenase in the digestive gland and T complex protein 1 (TCP1)) and 6 phosphogluconate dehydrogenase in the gills represent useful biomarkers for the ecotoxicological characterization of psychiatric hospital effluents in this species.
- Interspecific variability of endocrine disruption and oxidative stress in two bivalve species from the Ria Formosa Lagoon (south coast of Portugal)Publication . Pereira, Catarina; Gomes, Tânia; Cardoso, Catia; Almeida, Ana Catarina; Araújo, Olinda; Bebianno, Maria João; Cravo, AlexandraEstuaries are highly productive ecosystems that have been increasingly affected by anthropogenic activities. In this study, the presence of endocrine disrupting compounds (EDCs) and their relation to oxidative stress were assessed in two bivalve species (mussels Mytilus galloprovincialis and clams Ruditapes decussatus) from the Ria Formosa Lagoon (south Portugal). We applied the alkali-labile phosphate (ALP) assay to determine vitellogenin-like protein levels, and the lipid peroxidation (LPO) method to assess oxidative damage. Mussels and clams exhibited the same pattern of ALP concentrations, with no differences between genders and higher levels in winter. R. decussatus showed higher ALP values than M. galloprovincialis, possibly associated with a stronger responsiveness of clams to EDCs or due to the influence of the reproductive cycle. Mussels exhibited a more evident seasonal effect for LPO, indicating that these organisms are more influenced by seasonal fluctuations in the water column compared to the sediment-associated clams. Both species appear to be under the influence of EDC exposure (which could induce Vg-like protein synthesis) and oxidative stressors (leading to lipid peroxidation) in the Ria Formosa Lagoon, particularly in winter, reflecting the presence of different contaminants in Ria Formosa and environmental changes, as well as complex interactions between them.
- Subcellular partitioning kinetics, metallothionein response and oxidative damage in the marine mussel Mytilus galloprovincialis exposed to cadmium-based quantum dotsPublication . Rocha, Thiago Lopes; Gomes, Tânia; Durigon, Emerson Giuliani; Bebianno, Maria JoãoThe environmental health impact of metal-based nanomaterials is of emerging concern, but their metabolism and detoxification pathways in marine bioindicator species remain unclear. This study investigated the role of subcellular partitioning kinetics, metallothioneins (MTs) response and oxidative damage (lipid peroxidation LPO) in the marine mussel Mytilus galloprovincialis exposed to CdTe quantum dots (QDs) in comparison with its dissolved counterpart. Mussels were exposed to QDs and dissolved Cd for 21 days at 10 mu g Cd L-1 followed by a 50 days depuration. Higher Cd concentrations were detected in fractions containing mitochondria, nucleus and lysosomes, suggesting potential subcellular targets of QDs toxicity inmussel tissues. Tissue specific metabolism patterns were observed in mussels exposed to both Cd forms. Although MT levels were directly associated with Cd in both forms, QDs subcellular partitioning is linked to biologically active metal (BAM), but no increase in LPO occurred, while in the case of dissolved Cd levels are in the biologically detoxified metal (BDM) form, indicating nano-specific effects. Mussel gills showed lower detoxification capability of QDs, while the digestive gland is the major tissue for storage and detoxification of both Cd forms. Both mussel tissues were unable to completely eliminate the Cd accumulated in the QDs form (estimated half-life time > 50 days), highlighting the potential source of Cd and QDs toxicity for human and environmental health. Results indicate tissue specific metabolism patterns and nano-specific effects in marine mussel exposed to QDs. (C) 2016 Elsevier B.V. All rights reserved.
- Effects of copper oxide nanoparticles on tissue accumulation and antioxidant enzymes of galleria mellonella LPublication . Sezer Tuncsoy, Benay; Tuncsoy, Mustafa; Gomes, Tânia; Serrão Sousa, Vânia; Ribau Teixeira, Margarida; Bebianno, Maria João; Ozalp, PinarEffects of copper oxide nanoparticles (CuO NPs) were investigated in the midgut and fat body of Galleria mellonella. Fourth instar larvae were exposed to 10 µg Cu/L of CuO until becoming last instar larvae, and catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione-s-transferase (GST) and acetylcholinesterase (AChE) and metal accumulation were evaluated. Copper accumulation was observed in midgut and fat body tissues of G. mellonella larvae exposed to CuO NPs. CuO NPs increased CAT activities in midgut and fat body, while SOD activities were decreased. CuO NPs exhibited significant increases in GST activity in fat body, while no significant differences were observed in the midgut of G. mellonella larvae. AChE activity significantly decreased in the midgut of G. mellonella whereas there is no significant effect on fat body in CuO NPs exposed larvae. In overall, these findings demonstrate that tissue accumulation and oxidative stress that is countered by antioxidant enzymes occur when G. mellonella larvae exposed to environmental concentration of CuO nanoparticles.
- Effects of copper nanoparticles exposure in the mussel Mytilus galloprovincialisPublication . Gomes, Tânia; Pinheiro, J. P.; Cancio, I.; Pereira, Catarina Guerreiro; Cardoso, Cátia; Bebianno, Maria JoãoCuO NPs are widely used in various industrial and commercial applications. However, little is known about their potential toxicity or fate in the environment. In this study the effects of copper nanoparticles were investigated in the gills of mussels Mytilus galloprovincialis, comparative to Cu(2+). Mussels were exposed to 10 μg Cu·L(-1) of CuO NPs and Cu(2+) for 15 days, and biomarkers of oxidative stress, metal exposure and neurotoxicity evaluated. Results show that mussels accumulated copper in gills and responded differently to CuO NPs and Cu(2+), suggesting distinct modes of action. CuO NPs induced oxidative stress in mussels by overwhelming gills antioxidant defense system, while for Cu(2+) enzymatic activities remained unchanged or increased. CuO NPs and Cu(2+) originated lipid peroxidation in mussels despite different antioxidant efficiency. Moreover, an induction of MT was detected throughout the exposure in mussels exposed to nano and ionic Cu, more evident in CuO NPs exposure. Neurotoxic effects reflected as AChE inhibition were only detected at the end of the exposure period for both forms of copper. In overall, these findings show that filter-feeding organisms are significant targets for nanoparticle exposure and need to be included when evaluating the overall toxicological impact of nanoparticles in the aquatic environment.
- Accumulation and toxicity of copper oxide nanoparticles in the digestive gland of Mytilus galloprovincialisPublication . Gomes, Tânia; Pereira, Catarina Guerreiro; Cardoso, Cátia; Pinheiro, José Paulo; Cancio, I.; Bebianno, Maria JoãoGiven the wide use of CuO nanoparticles in various industrial and commercial applications they will inevitably end up in the aquatic environment. However, little information exists on their biological effects in bivalve species. Accordingly, mussels Mytilus galloprovincialis were exposed to 10 g Cu L−1 as CuO nanoparticles and Cu2+ for 15 days, and biomarkers of oxidative stress (superoxide dismutase, catalase and glutathione peroxidase), damage (lipid peroxidation) and metal exposure (metallothionein) were determined along with Cu accumulation in the digestive glands of mussels. Cu was linearly accumulated with time of exposure in mussels exposed to CuO nanoparticles, while in those exposed to Cu2+ elimination was significant by day 15. Both forms of Cu cause oxidative stress with distinct modes of action. Exposure to CuO nanoparticles induces lower SOD activity in digestive glands compared to those exposed to Cu2+, while CAT was only activated after 7 days of exposure to nano and ionic Cu, with contradictory effects after 15 days of exposure and GPX activities were similar. Lipid peroxidation levels increased in both Cu forms despite different antioxidant efficiency. Moreover, a linear induction of metallothionein was detected with time in mussels exposed to CuO nanoparticles, directly related to Cu accumulation, whereas in those exposed to Cu2+ metallothionein was only induced after 15 days of exposure. Since only a small fraction of soluble Cu fraction was released from CuO nanoparticles, the observed effects seem to be related to the nano form of Cu, with aggregation as a key factor. Overall, our results show that the digestive gland is susceptible to CuO nanoparticles related oxidative stress, and is also the main tissue for their accumulation.