1,721,188 research outputs found
Effects of nanomaterials in marine invertebrates
No full textThe development of nanotechnology will inevitably lead to the release of consistent amounts of nanomaterials (NMs) and nanoparticles (NPs) into marine ecosystems. Ecotoxicological studies have been carried out to identify potential biological targets of NPs, and suitable models for predicting their impact on the health of the marine environment. Recent studies in invertebrates mainly focused on NP accumulation and sub-lethal effects, rather than acute toxicity. Among marine invertebrates, bivalves represent by large the most studied group, with polychaetes and echinoderms also emerging as significant targets of NPs. However, major scientific gaps still need to be filled.
In this work, factors affecting the fate of NPs in the marine environment, and their consequent uptake/accumulation/toxicity in marine invertebrates will be summarized. The results show that in different model species, NP accumulation mainly occurs in digestive tract and gills. Data on sub-lethal effects and modes of action of different types of NPs (mainly metal oxides and metal based NPs) in marine invertebrates will be reviewed, in particular on immune function, oxidative stress and embryo development. Moreover, the possibility that such effects may be influenced by NP interactions with biomolecules in both external and internal environment will be introduced. In natural environmental media, NP interactions with polysaccharides, proteins and colloids may affect their agglomeration/aggregation and consequent bioavailability. Moreover, once within the organism, NPs are known to interact with plasma proteins, forming a protein corona that can affect particle uptake and toxicity in target cells in a physiological environment. These interactions, leading to the formation of eco-bio-coronas, may be crucial in determining particle behavior and effects also in marine biota. In order to classify NPs into groups and predict the implications of their release into the marine environment, information on their intrinsic properties is clearly insufficient, and a deeper understanding of NP eco/bio-interactions is required
The Invertebrate Immune System as a Model for Investigating the Environmental Impact of Nanoparticles
No full textInvertebrate Models for Investigating the Impact of Nanomaterials on Innate Immunity: The Example of the Marine Mussel Mytilus spp.
Full text linkEvaluating the interactions of nanomaterials (NMs) with the immune system is becoming an
essential part of assessing nanosafety, not only for human health, but also for organisms living in different
environments. The interactions between NMs and the components of the immune system in
wildlife have been recently intensively investigated. Invertebrates represent more than 90% of animal
species and are widespread in all environments, where they are subjected to a wide range of stressors.
Despite invertebrates lack an adaptive immunity, they have developed a potent and complex innate
immune system showing many commonalities to that of vertebrates. Conservation of the main mechanisms
of innate immunity may greatly help understanding the possible interactions of NMs with the immune system
across different taxa. However, the utilization of invertebrate models for immunosafety studies requires a thorough basic
knowledge on the physiological regulation of the immune response of the tested species, together with information on particle
behavior in the receiving environment, as well as routes of exposure in different cells and organisms. In this work,
available data on the effects of NMs on the immune system of invertebrates are summarized. In particular, the results obtained
in the marine bivalve, the mussel Mytilus, are summarized, demonstrating that mussel immune cells, the haemocytes,
represent a suitable model for investigating the impact of NMs on innate immunity. These results underline how the
utilization of invertebrate models represents a promising field for designing environmentally safer, "green" nanomaterials
Invertebrate Models for Investigating the Impact of Nanomaterials on Innate Immunity: The Example of the Marine Mussel Mytilus spp.
No full textEstrogenic compounds as exogenous modulators of physiological functions in molluscs: Signaling pathways and biological responses
No full textMolluscs have been widely utilized to evaluate the effects of estrogenic compounds, one of the most widespread classes of Endocrine Disrupting Chemicals-EDCs. However, knowledge on steroid signaling and metabolism in molluscs has considerably increased in the last decade: from these studies, a considerable debate emerged on the role of 'natural' steroids in physiology, in particular in reproduction, of this invertebrate group. In this work, available information on the effects and mechanisms of action of estrogens in molluscs will be reviewed, with particular emphasis on bivalves that, widespread in aquatic ecosystems, are most likely affected by exposure to estrogenic EDCs. Recent advances in steroid uptake and metabolism, and estrogen receptors-ERs in molluscs, as well as in estrogen signaling in vertebrates, will be considered. The results so far obtained with 17β-estradiol and different estrogenic compounds in the model bivalve Mytilus spp., demonstrate specific effects on immune function, development and metabolism. Transcriptomic data reveal non genomic estrogen signaling pathways in mussel tissues that are supported by new observations at the cellular level. In vitro and in vivo data show, through independent lines of evidence, that estrogens act through non-genomic signaling pathways in bivalves. In this light, regardless of whether molluscs synthesize estrogens de novo or not, and despite their ERs are not directly activated by ligand binding, estrogens can interact with multiple signaling components, leading to modulation of different physiological functions. Increasing knowledge in endocrine physiology of molluscs will provide a framework for a better evaluation and interpretation of data on the impact of estrogenic EDCs in this invertebrate group
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