Organic matter contents and degradation in a highly trawled area during fresh particle inputs (Gulf of Castellammare, southwestern Mediterranean)

Bottom trawling in the deep sea is one of the main drivers of sediment resuspension, eroding the seafloor and altering the content and composition of sedimentary organic matter (OM). The physical and biogeochemical impacts of bottom trawling were studied on the continental slope of the Gulf of Castellammare, Sicily (southwestern Mediterranean), through the analysis of two triplicate sediment cores collected at trawled and untrawled sites (∼550 m water depth) during the summer of 2016. Geochemical and sedimentological parameters (excess 210Pb, excess 234Th, 137Cs, dry bulk density, and grain size), elemental (organic carbon and nitrogen) and biochemical composition of sedimentary OM (proteins, carbohydrates, lipids), as well as its freshness (phytopigments) and degradation rates were determined in both coring locations. The untrawled site had a sedimentation rate of 0.15 cm yr−1 and presented a 6 cm thick surface mixed layer that contained siltier sediment with low excess 210Pb concentrations, possibly resulting from the resuspension, posterior advection, and eventual deposition of coarser and older sediment from adjacent trawling grounds. In contrast, the trawled site was eroded and presented compacted century-old sediment highly depleted in OM components, which were between 20 % and 60 % lower than those in the untrawled site. However, the upper 2 cm of the trawled site consisted of recently accumulated sediments enriched in excess 234Th, excess 210Pb, and phytopigments, while OM contents were similar to those from the untrawled core. This fresh sediment supported protein turnover rates of 0.025 d−1, which doubled those quantified in surface sediments of the untrawled site. The enhancement of remineralization rates in surface sediment of the trawled site was associated with the arrival of fresh particles on a chronically trawled deep-sea region that is generally deprived of OM. We conclude that the detrimental effects of bottom trawling can be temporarily and partially abated by the arrival of fresh and nutritionally rich OM, which stimulate the response of benthic communities. However, these ephemeral deposits are likely to be swiftly eroded due to the high trawling frequency over fishing grounds, highlighting the importance of establishing science-based management strategies to mitigate the impacts of bottom trawling

Mitochondrial Metabolism and EV Cargo of Endothelial Cells Is Affected in Presence of EVs Derived from MSCs on Which HIF Is Activated

Small extracellular vesicles (sEVs) derived from mesenchymal stem cells (MSCs) have attracted growing interest as a possible novel therapeutic agent for the management of different cardiovascular diseases (CVDs). Hypoxia significantly enhances the secretion of angiogenic mediators from MSCs as well as sEVs. The iron-chelating deferoxamine mesylate (DFO) is a stabilizer of hypoxia-inducible factor 1 and consequently used as a substitute for environmental hypoxia. The improved regenerative potential of DFO-treated MSCs has been attributed to the increased release of angiogenic factors, but whether this effect is also mediated by the secreted sEVs has not yet been investigated. In this study, we treated adipose-derived stem cells (ASCs) with a nontoxic dose of DFO to harvest sEVs (DFO-sEVs). Human umbilical vein endothelial cells (HUVECs) treated with DFO-sEVs underwent mRNA sequencing and miRNA profiling of sEV cargo (HUVEC-sEVs). The transcriptomes revealed the upregulation of mitochondrial genes linked to oxidative phosphorylation. Functional enrichment analysis on miRNAs of HUVEC-sEVs showed a connection with the signaling pathways of cell proliferation and angiogenesis. In conclusion, mesenchymal cells treated with DFO release sEVs that induce in the recipient endothelial cells molecular pathways and biological processes strongly linked to proliferation and angiogenesis

Detection of community-wide impacts of bottom trawl fishing on deep-sea assemblages using environmental DNA metabarcoding

Este artículo contiene 14 páginas, 7 figuras, 3 tablas.Although considerable research progress on the effects of anthropogenic disturbance in the deep sea has been made in recent years, our understanding of these impacts at community level remains limited. Here, we studied deep-sea assemblages of Sicily (Mediterranean Sea) subject to different intensities of benthic trawling using environmental DNA (eDNA) metabarcoding and taxonomic identification of meiofauna communities. Firstly, eDNA metabarcoding data did not detect trawling impacts using alpha diversity whereas meiofauna data detected a significant effect of trawling. Secondly, both eDNA and meiofauna data detected significantly different communities across distinct levels of trawling intensity when we examined beta diversity. Taxonomic assignment of the eDNA data revealed that Bryozoa was present only at untrawled sites, highlighting their vulnerability to trawling. Our results provide evidence for community-wide impacts of trawling, with different trawling intensities leading to distinct deep-sea communities. Finally, we highlight the need for further studies to unravel understudied deep-sea biodiversity.project funded by the European Community (Grant agreement n◦ 312762). L.E.H. was supported by the Natural Environmental Research Council (grant number NE/L002531/). C.L.I. was supported by the H2020 MSC Action HABISS (GA 890815). We are grateful to the staff at the Environmental Sequencing facility at the National Oceanography Centre Southampton and to members of the EU-FP7 ISLAND (Exploring SiciLian CAnyoN Dynamics) Cruise. Finally, this work acknowledges the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S) to ICM-CSIC.Peer reviewe

A multi-scale approach in the study of trawling-induced impact on the seafloor. Examples from the EU ISLAND Project

2018 Ocean Sciences Meeting, 11-16 February, in Portland, OregonIndustrial bottom trawl fishery is among the human activities with most impact on deep-sea ecosystems, due to its widespread geographical distribution and to its strong effects on renewable natural resources. One of the main goals of the EU Euforfleet-2 Project ISLAND (ExplorIng SiciLian CAnyoN Dynamics) was to explore the role of bottom trawling in altering the natural seafloor integrity at nested spatial and temporal scales. This holistic approach was adopted along the NW Sicilian margin (southern Mediterranean) across a depth range of 200-800 m. It spanned from the analysis of the seafloor complexity and related benthic habitats, the quantification of sedimentation rates and organic carbon content in surface sediments, up to monitoring the near-bottom water turbidity and the formation of nepheloid layers induced by on-going fishing activities. Remote sensing data and samples were collected based on the distribution of the trawling effort averaged from the VMS data (Vessel Monitoring System) analzyed over a period of 6 years (2009-2015). Selected areas with null, low and high fishing effort were explored and sampled through Multi Beam mapping, ROV dives, sediment cores, hydrographic profiling and instrumented mooring observations. Results showed a potential impact on the large scale seascape heterogeneity, smoothing the morphology of sediment-starved small scale gullies on regions undergoing the maximum effort. ROV videos showed differences in the habitat complexity between adjacent regions with different trawling effort, with impacted areas displaying a strongly reduced amount of benthic species along up to 80 cm deep trawl marks. Core analysis revealed that trawled open slope sectors present highly eroded sedimentary bottoms, significantly depleted of labile organic matter, whereas trawled submarine canyons revealed enhanced sedimentation rates due to resuspension processes generated by the trawlers. Increased water turbidity related to trawling activities was recorded both by hydrographic sections and by time series observations collected within a submarine canyon, downslope the fishing grounds. These compelling evidences suggest that sediment dynamics along the NW Sicilian margin are largely affected by bottom trawling activities, with an evident impact at different spatial and temporal scalesPeer Reviewe

Potential impact of bottom trawling activities on sedimentary organic matter in the Gulf of Castellammare (Sicily)

XXIII Congress of the Italian Association of Oceannography and Limnology, Functioning, alteration and restoration of aquatic ecosystems, 26-29 September 2017, Cagliari, Sardinia, Italy.-- XXIII Congresso della Associazione Italiana di Oceanologia e Limnologia - XXIII Congress of the Italian Association of Oceannography and Limnology, Funzionamento, alterazioni e recupero degli ecosistemi acquaticiPeer Reviewe

Impacts of bottom trawling on benthic trophic status and meiofauna in a deep-sea sedimentary environment (Gulf of Castellammare, southwestern Mediterranean Sea)

European Geosciences Union (EGU) General Assembly 2020, 4-8 May 2020The impacts of bottom trawling on the structure of benthic communities can be relatively nonselective, hitting biodiversity as a whole. This holds true also in the deep sea, where the impacts of trawling can be more severe and long-lasting than in shallow-waters, due to the reduced capacity for recovery and greater vulnerability of deep-sea organisms. For years, our knowledge of the impact of trawling on deep-water ecosystems has remained limited and has focused mainly on fish stocks and hard bottom systems. More recently, a number of studies have addressed the impacts of bottom trawling in the deep-sea sedimentary environments, and very few of them have focused on the impacts on meiofauna, though it is a key faunal component of deep-sea ecosystems. We investigated the impact of bottom trawling on the quantity, biochemical composition and nutritional value of sedimentary organic matter and meiofauna along the Sicilian Margin (Gulf of Castellammare, southwestern Mediterranean) at ca. 550 m depth, during the summer of 2016. Amount, biochemical composition and freshness of sedimentary OM, as well as the abundance and community composition of meiofauna were determined in sediment cores taken at both trawled and untrawled grounds. The continuous erosive processes in the trawled site have led, generally, to the depletion of OM contents (20-60% lower than those in the untrawled site), as well as to statistically significant differences from the untrawled site in its biochemical composition. Nevertheless, the upper 2 cm of the trawled site consisted of recently accumulated sediments, enriched in phytopigments, and bulk OM contents similar to those in the untrawled one, interpreted as a very recent input of fresh OM from the upper water column. The abundance of meiofauna in trawled grounds was significantly higher than that in untrawled ones, whereas no differences were observed between trawled and untrawled grounds deeper in the sediment. Differences in the meiofaunal community composition among sediment layers in each site were larger than those among sites. As previously reported, deep bottom trawling in the Gulf of Castellammare erodes large volumes of sediment, exposing old compacted sediment that is depleted in OM. This erosive action generally prevents the accumulation of fresh sediment. However, the episodic short-lived deposition of fresh organic detritus between hauls can lead to a temporary accumulation of fresh and bioavailable OM which, in turn, can induce a positive response in meiofauna abundance. These results pinpoint the need of considering the impacts of bottom trawling on the benthic communities of deep-sea sedimentary environments at temporal scales shorter than previously don

Surface sediment erosion and organic matter depletion induced by intense bottom trawling activities in the Gulf of Castellammare (Sicily)

2018 Ocean Sciences Meeting, 11-16 February, in Portland, OregonBottom trawling is a major driver of sedimentary dynamics in the deep sea, resuspending surface sediments and eroding the seafloor. Although the impacts of trawling on deep-sea sediment properties and the resulting impairment of the ecosystem functioning have been previously documented, its repercussions on the bioavailability of organic matter still need to be fully addressed. To provide insighits on this, biochemical composition of organic matter (proteins, lipids, carbohydrates, and phytopigments) along with sediment dry bulk density, grain size, and 210Pb concentrations were analyzed in triplicate sediment cores retrieved in trawled and untrawled sites from the Gulf of Castellammare, Sicily (Mediterranean Sea), during the EU Eurofleets-2 ISLAND (ExplorIng SiciLian CAnyoN Dynamics). The trawled site was severely eroded, as shown by the high dry bulk density and depleted excess 210Pb concentrations, whereas the excess 210Pb profile at the untrawled site revealed a 6 cm thick surface mixed layer derived from bioturbation overlaying softer sediments that had accumulated at an average rate of 0.15 cm yr-1. Overall, organic matter contents in the trawled site were 14-37% lower than those in the untrawled one. However, bioavailable organic matter (lipids, proteins, and phytopigments) concentrations in the uppermost layer were comparable in both trawled and untrawled sites, likely due to similar inputs of pelagic organic matter prior to the sampling period. Phytopigment concentrations decreased with depth along the cores at both sites, but at a ca. 20% higher rate in the trawled areas. This result suggests that persistent sediment resuspension and erosion due to trawling can modify food value of surficial sediments for the benthos more rapidly than biological consumption or sediment bioturbation. Then, we hypothesize that the biota in persistently trawled sediments may be more dependent upon the input from the overlaying water layers than that in untrawled sitesPeer Reviewe

Anthropogenic disturbance on the NW Sicilian Canyons (western Mediterranean): trawling-induced impact and marine litters

4th International Submarine Canyon Symposium (INCISE2018), 5-7 November 2018, Shenzhen, ChinaIndustrial bottom trawl fishery and marine litter are concerning environmental threats exerting a strong impact on deep-sea ecosystems, menacing the maintenance and preservation of renewable natural resources. One of the main goals of the EU Eurofleets-2 ISLAND (ExplorIng SiciLian CAnyoN Dynamics) expedition was to explore the role of bottom trawling in altering the natural sedimentary dynamics along the submarine canyons of the NW Sicilian Margin (western Mediterranean) and to quantify the marine litters within them. An holistic approach was adopted across a depth range of 150-800 m, spanning from the analysis of the seafloor complexity from Multi Beam (MB) bathymetry, the quantification of sedimentation rates and organic carbon content in surface sediments collected with a multi corer, the analysis of litters and benthic habitats from ROV videos. Remote sensing data and samples were collected based on the distribution of the trawling effort averaged from the Vessel Monitoring System (VMS) data analzyed over a period of 6 years (2009-2015). Submarine canyons with null, low and high fishing effort were explored and compared. Results showed a potential impact of trawling on the large-scale seascape heterogeneity, smoothing the morphology of small sediment-starved gullies on the regions undergoing the maximum effort. ROV videos showed differences in the habitat complexity between adjacent regions undergoing different trawling effort, with impacted areas having a strongly reduced biodiversity, with some exceptions for scavengers. Multi core analysis revealed that submarine canyons undergo enhanced sedimentation rates due to resuspension processes generated by the trawlers crossing their axes either the surrounding regions. Analysis of ROV videos show a strong qualitative difference in the amount of litters between trawled and untrawled canyons. Whereas trawled canyons show absence of litters on their grounds, untrawled canyons host a high amount of litters, which was widespread either organized in several small islands, 1 to 3 m wide. Canyons most probably function as a sink hole for marine debris transported with bottom currents up to the visited depth of 800 m. Plastic is the greatest contributor to seabed litter (40%), followed by large items such as tires, oil drums and metal sheets (20%) and fishing material (longlines and nets - 15%). These compelling evidences suggest that NW Sicilian canyons are largely subject to the effect of threatening human activities, with an evident impact at different spatial and temporal scalesPeer Reviewe

Organic matter contents and degradation in a highly trawled area during fresh particle inputs (Gulf of Castellammare, southwestern Mediterranean)

Unidad de excelencia María de Maeztu MdM-2015-0552Bottom trawling in the deep sea is one of the main drivers of sediment resuspension, eroding the seafloor and altering the content and composition of sedimentary organic matter (OM). The physical and biogeochemical impacts of bottom trawling were studied on the continental slope of the Gulf of Castellammare, Sicily (southwestern Mediterranean), through the analysis of two triplicate sediment cores collected at trawled and untrawled sites (ĝ'1/4550 m water depth) during the summer of 2016. Geochemical and sedimentological parameters (excess 210Pb, excess 234Th, 137Cs, dry bulk density, and grain size), elemental (organic carbon and nitrogen) and biochemical composition of sedimentary OM (proteins, carbohydrates, lipids), as well as its freshness (phytopigments) and degradation rates were determined in both coring locations. The untrawled site had a sedimentation rate of 0.15 cm yr-1 and presented a 6 cm thick surface mixed layer that contained siltier sediment with low excess 210Pb concentrations, possibly resulting from the resuspension, posterior advection, and eventual deposition of coarser and older sediment from adjacent trawling grounds. In contrast, the trawled site was eroded and presented compacted century-old sediment highly depleted in OM components, which were between 20 % and 60 % lower than those in the untrawled site. However, the upper 2 cm of the trawled site consisted of recently accumulated sediments enriched in excess 234Th, excess 210Pb, and phytopigments, while OM contents were similar to those from the untrawled core. This fresh sediment supported protein turnover rates of 0.025 d-1, which doubled those quantified in surface sediments of the untrawled site. The enhancement of remineralization rates in surface sediment of the trawled site was associated with the arrival of fresh particles on a chronically trawled deep-sea region that is generally deprived of OM. We conclude that the detrimental effects of bottom trawling can be temporarily and partially abated by the arrival of fresh and nutritionally rich OM, which stimulate the response of benthic communities. However, these ephemeral deposits are likely to be swiftly eroded due to the high trawling frequency over fishing grounds, highlighting the importance of establishing science-based management strategies to mitigate the impacts of bottom trawling

Target therapies plus somatostatin analogues in NETs: a network meta-analysis

Although combination therapy is not recommended in patients with gastro-entero-pancreatic (GEP) neuroendocrine tumors (NETs), this strategy is widely used in clinical practice. This network meta-analysis of randomized trials evaluates targeted therapies and somatostatin analogues in GEP advanced NETs, either alone or in combination, comparing the efficacy of different single or combined treatment strategies in terms of progression-free survival (PFS). Interventions were grouped as analogues, everolimus, everolimus plus SSAs, sunitinib and placebo. In a secondary analysis, we also assessed the efficacy of individual specific pharmacological treatments versus placebo or each other. From 83 studies identified, 8 randomized controlled trials were selected, with a total of 1849 patients with either functioning or non-functioning NETs. The analysis confirmed the superiority of all treatments over placebo (HR ranging from 0.34, 95% CI: 0.24-0.37 with the combination of everolimus plus SSAs to 0.42, 0.31-0.57 with the analogues; moderate quality of evidence). On ranking analysis, the combination of everolimus plus SSA (P score=0.86) and then everolimus alone (P score=0.65) ranked highest in increasing PFS. On comparative evaluation of different interventions, pasireotide (P score=0.96) and everolimus+octreotide (P score=0.82) ranked as the best pharmacological treatment options. Our findings support the use of combination therapy in the treatment of functioning and non-functioning GEP NETs. The role of pasireotide should be explored in selected subgroups of patients. Last, the combination of everolimus and octreotide appears promising and should be more widely considered in clinical practice