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Fiori, L.

Publications and source records attributed to Fiori, L..

2 recordsLinked to original sources

One more avenue for whale-watching contributions to science: the study of cetacean-cephalopod interactions

Cephalopods are the primary source of food for several species of odontocetes. The unstable nature of this trophic resource is likely to affect the ecology of their cetacean predators, and this can be reflected on their conservation status but also on the tourist activities which target the observation of these animals. However, the study of the cetacean-cephalopod interaction is limited by the heavy logistics and expense of dedicated scientific campaigns. Fortunately, this gap can be filled by coupling modern molecular tools with indirect sampling methods. In this note we test if whale watching activities, which represent an intense observation effort worldwide, could be a source of material for studies of cetacean-cephalopod interactions. All contacted companies welcomed the invitation and received the sampling kit. Nine samples were collected, most of them in close association with sperm whales. All samples were determined as the seven-arm octopus Haliphron atlanticus (Octopoda, Alloposidae). We conclude that, although the Azores may have particularly favorable conditions for participatory science, similar programs can be replicated elsewhere

ecology↗

Neuron-derived extracellular vesicles extracted from plasma show altered size and miRNA cargo as a function of antidepressant drug response

Previous work has demonstrated that microRNAs (miRNAs) change as a function of antidepressant treatment (ADT) response. However, it is unclear how representative these peripherally detected miRNA changes are to those occurring in the brain. This study aimed to use peripherally extracted neuron-derived extracellular vesicles (NDEVs) to circumvent these limitations and investigate neuronal miRNA changes associated with antidepressant response. Samples were collected at two time points (baseline and after 8 weeks of follow-up) from depressed patients who responded (N=20) and did not respond (N=20) to escitalopram treatment, as well as controls (N=20). Total extracellular vesicles (EVs) were extracted from plasma, and then further enriched for NDEVs by immunoprecipitation with L1CAM. EV size was measured using tunable resistive pulse sensing, and NDEV miRNA cargo was extracted and sequenced. Subsequently, studies in cell lines and postmortem tissue were conducted. Characterization of NDEVs revealed they were smaller than other EVs isolated from plasma (p<0.0001), had brain-specific neuronal markers, and contained miRNAs enriched for brain functions (p<0.0001) Furthermore, NDEVs from depressed patients were smaller than controls (p<0.05), and NDEV size increased with ADT response (p<0.01). Finally, changes in NDEV cargo, specifically changes in miR-21-5p, miR-30d-5p and miR-486-5p together (p<0.01), were associated with ADT response. Targets of these three miRNAs were altered in brain tissue from depressed individuals (p<0.05). Together, this study indicates that changes in peripherally isolated NDEVs can act as both a clinically accessible and informative biomarker of ADT response specifically through size and cargo.

neuroscience↗